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Merge branch 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[thirdparty/linux.git] / fs / btrfs / inode.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/bio.h>
8 #include <linux/buffer_head.h>
9 #include <linux/file.h>
10 #include <linux/fs.h>
11 #include <linux/pagemap.h>
12 #include <linux/highmem.h>
13 #include <linux/time.h>
14 #include <linux/init.h>
15 #include <linux/string.h>
16 #include <linux/backing-dev.h>
17 #include <linux/writeback.h>
18 #include <linux/compat.h>
19 #include <linux/xattr.h>
20 #include <linux/posix_acl.h>
21 #include <linux/falloc.h>
22 #include <linux/slab.h>
23 #include <linux/ratelimit.h>
24 #include <linux/btrfs.h>
25 #include <linux/blkdev.h>
26 #include <linux/posix_acl_xattr.h>
27 #include <linux/uio.h>
28 #include <linux/magic.h>
29 #include <linux/iversion.h>
30 #include <asm/unaligned.h>
31 #include "ctree.h"
32 #include "disk-io.h"
33 #include "transaction.h"
34 #include "btrfs_inode.h"
35 #include "print-tree.h"
36 #include "ordered-data.h"
37 #include "xattr.h"
38 #include "tree-log.h"
39 #include "volumes.h"
40 #include "compression.h"
41 #include "locking.h"
42 #include "free-space-cache.h"
43 #include "inode-map.h"
44 #include "backref.h"
45 #include "props.h"
46 #include "qgroup.h"
47 #include "dedupe.h"
48
49 struct btrfs_iget_args {
50 struct btrfs_key *location;
51 struct btrfs_root *root;
52 };
53
54 struct btrfs_dio_data {
55 u64 reserve;
56 u64 unsubmitted_oe_range_start;
57 u64 unsubmitted_oe_range_end;
58 int overwrite;
59 };
60
61 static const struct inode_operations btrfs_dir_inode_operations;
62 static const struct inode_operations btrfs_symlink_inode_operations;
63 static const struct inode_operations btrfs_dir_ro_inode_operations;
64 static const struct inode_operations btrfs_special_inode_operations;
65 static const struct inode_operations btrfs_file_inode_operations;
66 static const struct address_space_operations btrfs_aops;
67 static const struct file_operations btrfs_dir_file_operations;
68 static const struct extent_io_ops btrfs_extent_io_ops;
69
70 static struct kmem_cache *btrfs_inode_cachep;
71 struct kmem_cache *btrfs_trans_handle_cachep;
72 struct kmem_cache *btrfs_path_cachep;
73 struct kmem_cache *btrfs_free_space_cachep;
74
75 #define S_SHIFT 12
76 static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
77 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
78 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
79 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
80 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
81 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
82 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
83 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
84 };
85
86 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
87 static int btrfs_truncate(struct inode *inode, bool skip_writeback);
88 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
89 static noinline int cow_file_range(struct inode *inode,
90 struct page *locked_page,
91 u64 start, u64 end, u64 delalloc_end,
92 int *page_started, unsigned long *nr_written,
93 int unlock, struct btrfs_dedupe_hash *hash);
94 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
95 u64 orig_start, u64 block_start,
96 u64 block_len, u64 orig_block_len,
97 u64 ram_bytes, int compress_type,
98 int type);
99
100 static void __endio_write_update_ordered(struct inode *inode,
101 const u64 offset, const u64 bytes,
102 const bool uptodate);
103
104 /*
105 * Cleanup all submitted ordered extents in specified range to handle errors
106 * from the fill_dellaloc() callback.
107 *
108 * NOTE: caller must ensure that when an error happens, it can not call
109 * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING
110 * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata
111 * to be released, which we want to happen only when finishing the ordered
112 * extent (btrfs_finish_ordered_io()). Also note that the caller of the
113 * fill_delalloc() callback already does proper cleanup for the first page of
114 * the range, that is, it invokes the callback writepage_end_io_hook() for the
115 * range of the first page.
116 */
117 static inline void btrfs_cleanup_ordered_extents(struct inode *inode,
118 const u64 offset,
119 const u64 bytes)
120 {
121 unsigned long index = offset >> PAGE_SHIFT;
122 unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT;
123 struct page *page;
124
125 while (index <= end_index) {
126 page = find_get_page(inode->i_mapping, index);
127 index++;
128 if (!page)
129 continue;
130 ClearPagePrivate2(page);
131 put_page(page);
132 }
133 return __endio_write_update_ordered(inode, offset + PAGE_SIZE,
134 bytes - PAGE_SIZE, false);
135 }
136
137 static int btrfs_dirty_inode(struct inode *inode);
138
139 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
140 void btrfs_test_inode_set_ops(struct inode *inode)
141 {
142 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
143 }
144 #endif
145
146 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
147 struct inode *inode, struct inode *dir,
148 const struct qstr *qstr)
149 {
150 int err;
151
152 err = btrfs_init_acl(trans, inode, dir);
153 if (!err)
154 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
155 return err;
156 }
157
158 /*
159 * this does all the hard work for inserting an inline extent into
160 * the btree. The caller should have done a btrfs_drop_extents so that
161 * no overlapping inline items exist in the btree
162 */
163 static int insert_inline_extent(struct btrfs_trans_handle *trans,
164 struct btrfs_path *path, int extent_inserted,
165 struct btrfs_root *root, struct inode *inode,
166 u64 start, size_t size, size_t compressed_size,
167 int compress_type,
168 struct page **compressed_pages)
169 {
170 struct extent_buffer *leaf;
171 struct page *page = NULL;
172 char *kaddr;
173 unsigned long ptr;
174 struct btrfs_file_extent_item *ei;
175 int ret;
176 size_t cur_size = size;
177 unsigned long offset;
178
179 if (compressed_size && compressed_pages)
180 cur_size = compressed_size;
181
182 inode_add_bytes(inode, size);
183
184 if (!extent_inserted) {
185 struct btrfs_key key;
186 size_t datasize;
187
188 key.objectid = btrfs_ino(BTRFS_I(inode));
189 key.offset = start;
190 key.type = BTRFS_EXTENT_DATA_KEY;
191
192 datasize = btrfs_file_extent_calc_inline_size(cur_size);
193 path->leave_spinning = 1;
194 ret = btrfs_insert_empty_item(trans, root, path, &key,
195 datasize);
196 if (ret)
197 goto fail;
198 }
199 leaf = path->nodes[0];
200 ei = btrfs_item_ptr(leaf, path->slots[0],
201 struct btrfs_file_extent_item);
202 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
203 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
204 btrfs_set_file_extent_encryption(leaf, ei, 0);
205 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
206 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
207 ptr = btrfs_file_extent_inline_start(ei);
208
209 if (compress_type != BTRFS_COMPRESS_NONE) {
210 struct page *cpage;
211 int i = 0;
212 while (compressed_size > 0) {
213 cpage = compressed_pages[i];
214 cur_size = min_t(unsigned long, compressed_size,
215 PAGE_SIZE);
216
217 kaddr = kmap_atomic(cpage);
218 write_extent_buffer(leaf, kaddr, ptr, cur_size);
219 kunmap_atomic(kaddr);
220
221 i++;
222 ptr += cur_size;
223 compressed_size -= cur_size;
224 }
225 btrfs_set_file_extent_compression(leaf, ei,
226 compress_type);
227 } else {
228 page = find_get_page(inode->i_mapping,
229 start >> PAGE_SHIFT);
230 btrfs_set_file_extent_compression(leaf, ei, 0);
231 kaddr = kmap_atomic(page);
232 offset = start & (PAGE_SIZE - 1);
233 write_extent_buffer(leaf, kaddr + offset, ptr, size);
234 kunmap_atomic(kaddr);
235 put_page(page);
236 }
237 btrfs_mark_buffer_dirty(leaf);
238 btrfs_release_path(path);
239
240 /*
241 * we're an inline extent, so nobody can
242 * extend the file past i_size without locking
243 * a page we already have locked.
244 *
245 * We must do any isize and inode updates
246 * before we unlock the pages. Otherwise we
247 * could end up racing with unlink.
248 */
249 BTRFS_I(inode)->disk_i_size = inode->i_size;
250 ret = btrfs_update_inode(trans, root, inode);
251
252 fail:
253 return ret;
254 }
255
256
257 /*
258 * conditionally insert an inline extent into the file. This
259 * does the checks required to make sure the data is small enough
260 * to fit as an inline extent.
261 */
262 static noinline int cow_file_range_inline(struct inode *inode, u64 start,
263 u64 end, size_t compressed_size,
264 int compress_type,
265 struct page **compressed_pages)
266 {
267 struct btrfs_root *root = BTRFS_I(inode)->root;
268 struct btrfs_fs_info *fs_info = root->fs_info;
269 struct btrfs_trans_handle *trans;
270 u64 isize = i_size_read(inode);
271 u64 actual_end = min(end + 1, isize);
272 u64 inline_len = actual_end - start;
273 u64 aligned_end = ALIGN(end, fs_info->sectorsize);
274 u64 data_len = inline_len;
275 int ret;
276 struct btrfs_path *path;
277 int extent_inserted = 0;
278 u32 extent_item_size;
279
280 if (compressed_size)
281 data_len = compressed_size;
282
283 if (start > 0 ||
284 actual_end > fs_info->sectorsize ||
285 data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) ||
286 (!compressed_size &&
287 (actual_end & (fs_info->sectorsize - 1)) == 0) ||
288 end + 1 < isize ||
289 data_len > fs_info->max_inline) {
290 return 1;
291 }
292
293 path = btrfs_alloc_path();
294 if (!path)
295 return -ENOMEM;
296
297 trans = btrfs_join_transaction(root);
298 if (IS_ERR(trans)) {
299 btrfs_free_path(path);
300 return PTR_ERR(trans);
301 }
302 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
303
304 if (compressed_size && compressed_pages)
305 extent_item_size = btrfs_file_extent_calc_inline_size(
306 compressed_size);
307 else
308 extent_item_size = btrfs_file_extent_calc_inline_size(
309 inline_len);
310
311 ret = __btrfs_drop_extents(trans, root, inode, path,
312 start, aligned_end, NULL,
313 1, 1, extent_item_size, &extent_inserted);
314 if (ret) {
315 btrfs_abort_transaction(trans, ret);
316 goto out;
317 }
318
319 if (isize > actual_end)
320 inline_len = min_t(u64, isize, actual_end);
321 ret = insert_inline_extent(trans, path, extent_inserted,
322 root, inode, start,
323 inline_len, compressed_size,
324 compress_type, compressed_pages);
325 if (ret && ret != -ENOSPC) {
326 btrfs_abort_transaction(trans, ret);
327 goto out;
328 } else if (ret == -ENOSPC) {
329 ret = 1;
330 goto out;
331 }
332
333 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
334 btrfs_drop_extent_cache(BTRFS_I(inode), start, aligned_end - 1, 0);
335 out:
336 /*
337 * Don't forget to free the reserved space, as for inlined extent
338 * it won't count as data extent, free them directly here.
339 * And at reserve time, it's always aligned to page size, so
340 * just free one page here.
341 */
342 btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE);
343 btrfs_free_path(path);
344 btrfs_end_transaction(trans);
345 return ret;
346 }
347
348 struct async_extent {
349 u64 start;
350 u64 ram_size;
351 u64 compressed_size;
352 struct page **pages;
353 unsigned long nr_pages;
354 int compress_type;
355 struct list_head list;
356 };
357
358 struct async_cow {
359 struct inode *inode;
360 struct btrfs_root *root;
361 struct page *locked_page;
362 u64 start;
363 u64 end;
364 unsigned int write_flags;
365 struct list_head extents;
366 struct btrfs_work work;
367 };
368
369 static noinline int add_async_extent(struct async_cow *cow,
370 u64 start, u64 ram_size,
371 u64 compressed_size,
372 struct page **pages,
373 unsigned long nr_pages,
374 int compress_type)
375 {
376 struct async_extent *async_extent;
377
378 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
379 BUG_ON(!async_extent); /* -ENOMEM */
380 async_extent->start = start;
381 async_extent->ram_size = ram_size;
382 async_extent->compressed_size = compressed_size;
383 async_extent->pages = pages;
384 async_extent->nr_pages = nr_pages;
385 async_extent->compress_type = compress_type;
386 list_add_tail(&async_extent->list, &cow->extents);
387 return 0;
388 }
389
390 static inline int inode_need_compress(struct inode *inode, u64 start, u64 end)
391 {
392 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
393
394 /* force compress */
395 if (btrfs_test_opt(fs_info, FORCE_COMPRESS))
396 return 1;
397 /* defrag ioctl */
398 if (BTRFS_I(inode)->defrag_compress)
399 return 1;
400 /* bad compression ratios */
401 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
402 return 0;
403 if (btrfs_test_opt(fs_info, COMPRESS) ||
404 BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS ||
405 BTRFS_I(inode)->prop_compress)
406 return btrfs_compress_heuristic(inode, start, end);
407 return 0;
408 }
409
410 static inline void inode_should_defrag(struct btrfs_inode *inode,
411 u64 start, u64 end, u64 num_bytes, u64 small_write)
412 {
413 /* If this is a small write inside eof, kick off a defrag */
414 if (num_bytes < small_write &&
415 (start > 0 || end + 1 < inode->disk_i_size))
416 btrfs_add_inode_defrag(NULL, inode);
417 }
418
419 /*
420 * we create compressed extents in two phases. The first
421 * phase compresses a range of pages that have already been
422 * locked (both pages and state bits are locked).
423 *
424 * This is done inside an ordered work queue, and the compression
425 * is spread across many cpus. The actual IO submission is step
426 * two, and the ordered work queue takes care of making sure that
427 * happens in the same order things were put onto the queue by
428 * writepages and friends.
429 *
430 * If this code finds it can't get good compression, it puts an
431 * entry onto the work queue to write the uncompressed bytes. This
432 * makes sure that both compressed inodes and uncompressed inodes
433 * are written in the same order that the flusher thread sent them
434 * down.
435 */
436 static noinline void compress_file_range(struct inode *inode,
437 struct page *locked_page,
438 u64 start, u64 end,
439 struct async_cow *async_cow,
440 int *num_added)
441 {
442 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
443 u64 blocksize = fs_info->sectorsize;
444 u64 actual_end;
445 u64 isize = i_size_read(inode);
446 int ret = 0;
447 struct page **pages = NULL;
448 unsigned long nr_pages;
449 unsigned long total_compressed = 0;
450 unsigned long total_in = 0;
451 int i;
452 int will_compress;
453 int compress_type = fs_info->compress_type;
454 int redirty = 0;
455
456 inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1,
457 SZ_16K);
458
459 actual_end = min_t(u64, isize, end + 1);
460 again:
461 will_compress = 0;
462 nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1;
463 BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0);
464 nr_pages = min_t(unsigned long, nr_pages,
465 BTRFS_MAX_COMPRESSED / PAGE_SIZE);
466
467 /*
468 * we don't want to send crud past the end of i_size through
469 * compression, that's just a waste of CPU time. So, if the
470 * end of the file is before the start of our current
471 * requested range of bytes, we bail out to the uncompressed
472 * cleanup code that can deal with all of this.
473 *
474 * It isn't really the fastest way to fix things, but this is a
475 * very uncommon corner.
476 */
477 if (actual_end <= start)
478 goto cleanup_and_bail_uncompressed;
479
480 total_compressed = actual_end - start;
481
482 /*
483 * skip compression for a small file range(<=blocksize) that
484 * isn't an inline extent, since it doesn't save disk space at all.
485 */
486 if (total_compressed <= blocksize &&
487 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
488 goto cleanup_and_bail_uncompressed;
489
490 total_compressed = min_t(unsigned long, total_compressed,
491 BTRFS_MAX_UNCOMPRESSED);
492 total_in = 0;
493 ret = 0;
494
495 /*
496 * we do compression for mount -o compress and when the
497 * inode has not been flagged as nocompress. This flag can
498 * change at any time if we discover bad compression ratios.
499 */
500 if (inode_need_compress(inode, start, end)) {
501 WARN_ON(pages);
502 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
503 if (!pages) {
504 /* just bail out to the uncompressed code */
505 goto cont;
506 }
507
508 if (BTRFS_I(inode)->defrag_compress)
509 compress_type = BTRFS_I(inode)->defrag_compress;
510 else if (BTRFS_I(inode)->prop_compress)
511 compress_type = BTRFS_I(inode)->prop_compress;
512
513 /*
514 * we need to call clear_page_dirty_for_io on each
515 * page in the range. Otherwise applications with the file
516 * mmap'd can wander in and change the page contents while
517 * we are compressing them.
518 *
519 * If the compression fails for any reason, we set the pages
520 * dirty again later on.
521 *
522 * Note that the remaining part is redirtied, the start pointer
523 * has moved, the end is the original one.
524 */
525 if (!redirty) {
526 extent_range_clear_dirty_for_io(inode, start, end);
527 redirty = 1;
528 }
529
530 /* Compression level is applied here and only here */
531 ret = btrfs_compress_pages(
532 compress_type | (fs_info->compress_level << 4),
533 inode->i_mapping, start,
534 pages,
535 &nr_pages,
536 &total_in,
537 &total_compressed);
538
539 if (!ret) {
540 unsigned long offset = total_compressed &
541 (PAGE_SIZE - 1);
542 struct page *page = pages[nr_pages - 1];
543 char *kaddr;
544
545 /* zero the tail end of the last page, we might be
546 * sending it down to disk
547 */
548 if (offset) {
549 kaddr = kmap_atomic(page);
550 memset(kaddr + offset, 0,
551 PAGE_SIZE - offset);
552 kunmap_atomic(kaddr);
553 }
554 will_compress = 1;
555 }
556 }
557 cont:
558 if (start == 0) {
559 /* lets try to make an inline extent */
560 if (ret || total_in < actual_end) {
561 /* we didn't compress the entire range, try
562 * to make an uncompressed inline extent.
563 */
564 ret = cow_file_range_inline(inode, start, end, 0,
565 BTRFS_COMPRESS_NONE, NULL);
566 } else {
567 /* try making a compressed inline extent */
568 ret = cow_file_range_inline(inode, start, end,
569 total_compressed,
570 compress_type, pages);
571 }
572 if (ret <= 0) {
573 unsigned long clear_flags = EXTENT_DELALLOC |
574 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
575 EXTENT_DO_ACCOUNTING;
576 unsigned long page_error_op;
577
578 page_error_op = ret < 0 ? PAGE_SET_ERROR : 0;
579
580 /*
581 * inline extent creation worked or returned error,
582 * we don't need to create any more async work items.
583 * Unlock and free up our temp pages.
584 *
585 * We use DO_ACCOUNTING here because we need the
586 * delalloc_release_metadata to be done _after_ we drop
587 * our outstanding extent for clearing delalloc for this
588 * range.
589 */
590 extent_clear_unlock_delalloc(inode, start, end, end,
591 NULL, clear_flags,
592 PAGE_UNLOCK |
593 PAGE_CLEAR_DIRTY |
594 PAGE_SET_WRITEBACK |
595 page_error_op |
596 PAGE_END_WRITEBACK);
597 goto free_pages_out;
598 }
599 }
600
601 if (will_compress) {
602 /*
603 * we aren't doing an inline extent round the compressed size
604 * up to a block size boundary so the allocator does sane
605 * things
606 */
607 total_compressed = ALIGN(total_compressed, blocksize);
608
609 /*
610 * one last check to make sure the compression is really a
611 * win, compare the page count read with the blocks on disk,
612 * compression must free at least one sector size
613 */
614 total_in = ALIGN(total_in, PAGE_SIZE);
615 if (total_compressed + blocksize <= total_in) {
616 *num_added += 1;
617
618 /*
619 * The async work queues will take care of doing actual
620 * allocation on disk for these compressed pages, and
621 * will submit them to the elevator.
622 */
623 add_async_extent(async_cow, start, total_in,
624 total_compressed, pages, nr_pages,
625 compress_type);
626
627 if (start + total_in < end) {
628 start += total_in;
629 pages = NULL;
630 cond_resched();
631 goto again;
632 }
633 return;
634 }
635 }
636 if (pages) {
637 /*
638 * the compression code ran but failed to make things smaller,
639 * free any pages it allocated and our page pointer array
640 */
641 for (i = 0; i < nr_pages; i++) {
642 WARN_ON(pages[i]->mapping);
643 put_page(pages[i]);
644 }
645 kfree(pages);
646 pages = NULL;
647 total_compressed = 0;
648 nr_pages = 0;
649
650 /* flag the file so we don't compress in the future */
651 if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) &&
652 !(BTRFS_I(inode)->prop_compress)) {
653 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
654 }
655 }
656 cleanup_and_bail_uncompressed:
657 /*
658 * No compression, but we still need to write the pages in the file
659 * we've been given so far. redirty the locked page if it corresponds
660 * to our extent and set things up for the async work queue to run
661 * cow_file_range to do the normal delalloc dance.
662 */
663 if (page_offset(locked_page) >= start &&
664 page_offset(locked_page) <= end)
665 __set_page_dirty_nobuffers(locked_page);
666 /* unlocked later on in the async handlers */
667
668 if (redirty)
669 extent_range_redirty_for_io(inode, start, end);
670 add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0,
671 BTRFS_COMPRESS_NONE);
672 *num_added += 1;
673
674 return;
675
676 free_pages_out:
677 for (i = 0; i < nr_pages; i++) {
678 WARN_ON(pages[i]->mapping);
679 put_page(pages[i]);
680 }
681 kfree(pages);
682 }
683
684 static void free_async_extent_pages(struct async_extent *async_extent)
685 {
686 int i;
687
688 if (!async_extent->pages)
689 return;
690
691 for (i = 0; i < async_extent->nr_pages; i++) {
692 WARN_ON(async_extent->pages[i]->mapping);
693 put_page(async_extent->pages[i]);
694 }
695 kfree(async_extent->pages);
696 async_extent->nr_pages = 0;
697 async_extent->pages = NULL;
698 }
699
700 /*
701 * phase two of compressed writeback. This is the ordered portion
702 * of the code, which only gets called in the order the work was
703 * queued. We walk all the async extents created by compress_file_range
704 * and send them down to the disk.
705 */
706 static noinline void submit_compressed_extents(struct inode *inode,
707 struct async_cow *async_cow)
708 {
709 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
710 struct async_extent *async_extent;
711 u64 alloc_hint = 0;
712 struct btrfs_key ins;
713 struct extent_map *em;
714 struct btrfs_root *root = BTRFS_I(inode)->root;
715 struct extent_io_tree *io_tree;
716 int ret = 0;
717
718 again:
719 while (!list_empty(&async_cow->extents)) {
720 async_extent = list_entry(async_cow->extents.next,
721 struct async_extent, list);
722 list_del(&async_extent->list);
723
724 io_tree = &BTRFS_I(inode)->io_tree;
725
726 retry:
727 /* did the compression code fall back to uncompressed IO? */
728 if (!async_extent->pages) {
729 int page_started = 0;
730 unsigned long nr_written = 0;
731
732 lock_extent(io_tree, async_extent->start,
733 async_extent->start +
734 async_extent->ram_size - 1);
735
736 /* allocate blocks */
737 ret = cow_file_range(inode, async_cow->locked_page,
738 async_extent->start,
739 async_extent->start +
740 async_extent->ram_size - 1,
741 async_extent->start +
742 async_extent->ram_size - 1,
743 &page_started, &nr_written, 0,
744 NULL);
745
746 /* JDM XXX */
747
748 /*
749 * if page_started, cow_file_range inserted an
750 * inline extent and took care of all the unlocking
751 * and IO for us. Otherwise, we need to submit
752 * all those pages down to the drive.
753 */
754 if (!page_started && !ret)
755 extent_write_locked_range(inode,
756 async_extent->start,
757 async_extent->start +
758 async_extent->ram_size - 1,
759 WB_SYNC_ALL);
760 else if (ret)
761 unlock_page(async_cow->locked_page);
762 kfree(async_extent);
763 cond_resched();
764 continue;
765 }
766
767 lock_extent(io_tree, async_extent->start,
768 async_extent->start + async_extent->ram_size - 1);
769
770 ret = btrfs_reserve_extent(root, async_extent->ram_size,
771 async_extent->compressed_size,
772 async_extent->compressed_size,
773 0, alloc_hint, &ins, 1, 1);
774 if (ret) {
775 free_async_extent_pages(async_extent);
776
777 if (ret == -ENOSPC) {
778 unlock_extent(io_tree, async_extent->start,
779 async_extent->start +
780 async_extent->ram_size - 1);
781
782 /*
783 * we need to redirty the pages if we decide to
784 * fallback to uncompressed IO, otherwise we
785 * will not submit these pages down to lower
786 * layers.
787 */
788 extent_range_redirty_for_io(inode,
789 async_extent->start,
790 async_extent->start +
791 async_extent->ram_size - 1);
792
793 goto retry;
794 }
795 goto out_free;
796 }
797 /*
798 * here we're doing allocation and writeback of the
799 * compressed pages
800 */
801 em = create_io_em(inode, async_extent->start,
802 async_extent->ram_size, /* len */
803 async_extent->start, /* orig_start */
804 ins.objectid, /* block_start */
805 ins.offset, /* block_len */
806 ins.offset, /* orig_block_len */
807 async_extent->ram_size, /* ram_bytes */
808 async_extent->compress_type,
809 BTRFS_ORDERED_COMPRESSED);
810 if (IS_ERR(em))
811 /* ret value is not necessary due to void function */
812 goto out_free_reserve;
813 free_extent_map(em);
814
815 ret = btrfs_add_ordered_extent_compress(inode,
816 async_extent->start,
817 ins.objectid,
818 async_extent->ram_size,
819 ins.offset,
820 BTRFS_ORDERED_COMPRESSED,
821 async_extent->compress_type);
822 if (ret) {
823 btrfs_drop_extent_cache(BTRFS_I(inode),
824 async_extent->start,
825 async_extent->start +
826 async_extent->ram_size - 1, 0);
827 goto out_free_reserve;
828 }
829 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
830
831 /*
832 * clear dirty, set writeback and unlock the pages.
833 */
834 extent_clear_unlock_delalloc(inode, async_extent->start,
835 async_extent->start +
836 async_extent->ram_size - 1,
837 async_extent->start +
838 async_extent->ram_size - 1,
839 NULL, EXTENT_LOCKED | EXTENT_DELALLOC,
840 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
841 PAGE_SET_WRITEBACK);
842 if (btrfs_submit_compressed_write(inode,
843 async_extent->start,
844 async_extent->ram_size,
845 ins.objectid,
846 ins.offset, async_extent->pages,
847 async_extent->nr_pages,
848 async_cow->write_flags)) {
849 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
850 struct page *p = async_extent->pages[0];
851 const u64 start = async_extent->start;
852 const u64 end = start + async_extent->ram_size - 1;
853
854 p->mapping = inode->i_mapping;
855 tree->ops->writepage_end_io_hook(p, start, end,
856 NULL, 0);
857 p->mapping = NULL;
858 extent_clear_unlock_delalloc(inode, start, end, end,
859 NULL, 0,
860 PAGE_END_WRITEBACK |
861 PAGE_SET_ERROR);
862 free_async_extent_pages(async_extent);
863 }
864 alloc_hint = ins.objectid + ins.offset;
865 kfree(async_extent);
866 cond_resched();
867 }
868 return;
869 out_free_reserve:
870 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
871 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
872 out_free:
873 extent_clear_unlock_delalloc(inode, async_extent->start,
874 async_extent->start +
875 async_extent->ram_size - 1,
876 async_extent->start +
877 async_extent->ram_size - 1,
878 NULL, EXTENT_LOCKED | EXTENT_DELALLOC |
879 EXTENT_DELALLOC_NEW |
880 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING,
881 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
882 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK |
883 PAGE_SET_ERROR);
884 free_async_extent_pages(async_extent);
885 kfree(async_extent);
886 goto again;
887 }
888
889 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
890 u64 num_bytes)
891 {
892 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
893 struct extent_map *em;
894 u64 alloc_hint = 0;
895
896 read_lock(&em_tree->lock);
897 em = search_extent_mapping(em_tree, start, num_bytes);
898 if (em) {
899 /*
900 * if block start isn't an actual block number then find the
901 * first block in this inode and use that as a hint. If that
902 * block is also bogus then just don't worry about it.
903 */
904 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
905 free_extent_map(em);
906 em = search_extent_mapping(em_tree, 0, 0);
907 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
908 alloc_hint = em->block_start;
909 if (em)
910 free_extent_map(em);
911 } else {
912 alloc_hint = em->block_start;
913 free_extent_map(em);
914 }
915 }
916 read_unlock(&em_tree->lock);
917
918 return alloc_hint;
919 }
920
921 /*
922 * when extent_io.c finds a delayed allocation range in the file,
923 * the call backs end up in this code. The basic idea is to
924 * allocate extents on disk for the range, and create ordered data structs
925 * in ram to track those extents.
926 *
927 * locked_page is the page that writepage had locked already. We use
928 * it to make sure we don't do extra locks or unlocks.
929 *
930 * *page_started is set to one if we unlock locked_page and do everything
931 * required to start IO on it. It may be clean and already done with
932 * IO when we return.
933 */
934 static noinline int cow_file_range(struct inode *inode,
935 struct page *locked_page,
936 u64 start, u64 end, u64 delalloc_end,
937 int *page_started, unsigned long *nr_written,
938 int unlock, struct btrfs_dedupe_hash *hash)
939 {
940 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
941 struct btrfs_root *root = BTRFS_I(inode)->root;
942 u64 alloc_hint = 0;
943 u64 num_bytes;
944 unsigned long ram_size;
945 u64 cur_alloc_size = 0;
946 u64 blocksize = fs_info->sectorsize;
947 struct btrfs_key ins;
948 struct extent_map *em;
949 unsigned clear_bits;
950 unsigned long page_ops;
951 bool extent_reserved = false;
952 int ret = 0;
953
954 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
955 WARN_ON_ONCE(1);
956 ret = -EINVAL;
957 goto out_unlock;
958 }
959
960 num_bytes = ALIGN(end - start + 1, blocksize);
961 num_bytes = max(blocksize, num_bytes);
962 ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy));
963
964 inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K);
965
966 if (start == 0) {
967 /* lets try to make an inline extent */
968 ret = cow_file_range_inline(inode, start, end, 0,
969 BTRFS_COMPRESS_NONE, NULL);
970 if (ret == 0) {
971 /*
972 * We use DO_ACCOUNTING here because we need the
973 * delalloc_release_metadata to be run _after_ we drop
974 * our outstanding extent for clearing delalloc for this
975 * range.
976 */
977 extent_clear_unlock_delalloc(inode, start, end,
978 delalloc_end, NULL,
979 EXTENT_LOCKED | EXTENT_DELALLOC |
980 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
981 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
982 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
983 PAGE_END_WRITEBACK);
984 *nr_written = *nr_written +
985 (end - start + PAGE_SIZE) / PAGE_SIZE;
986 *page_started = 1;
987 goto out;
988 } else if (ret < 0) {
989 goto out_unlock;
990 }
991 }
992
993 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
994 btrfs_drop_extent_cache(BTRFS_I(inode), start,
995 start + num_bytes - 1, 0);
996
997 while (num_bytes > 0) {
998 cur_alloc_size = num_bytes;
999 ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size,
1000 fs_info->sectorsize, 0, alloc_hint,
1001 &ins, 1, 1);
1002 if (ret < 0)
1003 goto out_unlock;
1004 cur_alloc_size = ins.offset;
1005 extent_reserved = true;
1006
1007 ram_size = ins.offset;
1008 em = create_io_em(inode, start, ins.offset, /* len */
1009 start, /* orig_start */
1010 ins.objectid, /* block_start */
1011 ins.offset, /* block_len */
1012 ins.offset, /* orig_block_len */
1013 ram_size, /* ram_bytes */
1014 BTRFS_COMPRESS_NONE, /* compress_type */
1015 BTRFS_ORDERED_REGULAR /* type */);
1016 if (IS_ERR(em)) {
1017 ret = PTR_ERR(em);
1018 goto out_reserve;
1019 }
1020 free_extent_map(em);
1021
1022 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
1023 ram_size, cur_alloc_size, 0);
1024 if (ret)
1025 goto out_drop_extent_cache;
1026
1027 if (root->root_key.objectid ==
1028 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1029 ret = btrfs_reloc_clone_csums(inode, start,
1030 cur_alloc_size);
1031 /*
1032 * Only drop cache here, and process as normal.
1033 *
1034 * We must not allow extent_clear_unlock_delalloc()
1035 * at out_unlock label to free meta of this ordered
1036 * extent, as its meta should be freed by
1037 * btrfs_finish_ordered_io().
1038 *
1039 * So we must continue until @start is increased to
1040 * skip current ordered extent.
1041 */
1042 if (ret)
1043 btrfs_drop_extent_cache(BTRFS_I(inode), start,
1044 start + ram_size - 1, 0);
1045 }
1046
1047 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
1048
1049 /* we're not doing compressed IO, don't unlock the first
1050 * page (which the caller expects to stay locked), don't
1051 * clear any dirty bits and don't set any writeback bits
1052 *
1053 * Do set the Private2 bit so we know this page was properly
1054 * setup for writepage
1055 */
1056 page_ops = unlock ? PAGE_UNLOCK : 0;
1057 page_ops |= PAGE_SET_PRIVATE2;
1058
1059 extent_clear_unlock_delalloc(inode, start,
1060 start + ram_size - 1,
1061 delalloc_end, locked_page,
1062 EXTENT_LOCKED | EXTENT_DELALLOC,
1063 page_ops);
1064 if (num_bytes < cur_alloc_size)
1065 num_bytes = 0;
1066 else
1067 num_bytes -= cur_alloc_size;
1068 alloc_hint = ins.objectid + ins.offset;
1069 start += cur_alloc_size;
1070 extent_reserved = false;
1071
1072 /*
1073 * btrfs_reloc_clone_csums() error, since start is increased
1074 * extent_clear_unlock_delalloc() at out_unlock label won't
1075 * free metadata of current ordered extent, we're OK to exit.
1076 */
1077 if (ret)
1078 goto out_unlock;
1079 }
1080 out:
1081 return ret;
1082
1083 out_drop_extent_cache:
1084 btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0);
1085 out_reserve:
1086 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
1087 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
1088 out_unlock:
1089 clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
1090 EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV;
1091 page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
1092 PAGE_END_WRITEBACK;
1093 /*
1094 * If we reserved an extent for our delalloc range (or a subrange) and
1095 * failed to create the respective ordered extent, then it means that
1096 * when we reserved the extent we decremented the extent's size from
1097 * the data space_info's bytes_may_use counter and incremented the
1098 * space_info's bytes_reserved counter by the same amount. We must make
1099 * sure extent_clear_unlock_delalloc() does not try to decrement again
1100 * the data space_info's bytes_may_use counter, therefore we do not pass
1101 * it the flag EXTENT_CLEAR_DATA_RESV.
1102 */
1103 if (extent_reserved) {
1104 extent_clear_unlock_delalloc(inode, start,
1105 start + cur_alloc_size,
1106 start + cur_alloc_size,
1107 locked_page,
1108 clear_bits,
1109 page_ops);
1110 start += cur_alloc_size;
1111 if (start >= end)
1112 goto out;
1113 }
1114 extent_clear_unlock_delalloc(inode, start, end, delalloc_end,
1115 locked_page,
1116 clear_bits | EXTENT_CLEAR_DATA_RESV,
1117 page_ops);
1118 goto out;
1119 }
1120
1121 /*
1122 * work queue call back to started compression on a file and pages
1123 */
1124 static noinline void async_cow_start(struct btrfs_work *work)
1125 {
1126 struct async_cow *async_cow;
1127 int num_added = 0;
1128 async_cow = container_of(work, struct async_cow, work);
1129
1130 compress_file_range(async_cow->inode, async_cow->locked_page,
1131 async_cow->start, async_cow->end, async_cow,
1132 &num_added);
1133 if (num_added == 0) {
1134 btrfs_add_delayed_iput(async_cow->inode);
1135 async_cow->inode = NULL;
1136 }
1137 }
1138
1139 /*
1140 * work queue call back to submit previously compressed pages
1141 */
1142 static noinline void async_cow_submit(struct btrfs_work *work)
1143 {
1144 struct btrfs_fs_info *fs_info;
1145 struct async_cow *async_cow;
1146 struct btrfs_root *root;
1147 unsigned long nr_pages;
1148
1149 async_cow = container_of(work, struct async_cow, work);
1150
1151 root = async_cow->root;
1152 fs_info = root->fs_info;
1153 nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >>
1154 PAGE_SHIFT;
1155
1156 /* atomic_sub_return implies a barrier */
1157 if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) <
1158 5 * SZ_1M)
1159 cond_wake_up_nomb(&fs_info->async_submit_wait);
1160
1161 if (async_cow->inode)
1162 submit_compressed_extents(async_cow->inode, async_cow);
1163 }
1164
1165 static noinline void async_cow_free(struct btrfs_work *work)
1166 {
1167 struct async_cow *async_cow;
1168 async_cow = container_of(work, struct async_cow, work);
1169 if (async_cow->inode)
1170 btrfs_add_delayed_iput(async_cow->inode);
1171 kfree(async_cow);
1172 }
1173
1174 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1175 u64 start, u64 end, int *page_started,
1176 unsigned long *nr_written,
1177 unsigned int write_flags)
1178 {
1179 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1180 struct async_cow *async_cow;
1181 struct btrfs_root *root = BTRFS_I(inode)->root;
1182 unsigned long nr_pages;
1183 u64 cur_end;
1184
1185 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1186 1, 0, NULL);
1187 while (start < end) {
1188 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
1189 BUG_ON(!async_cow); /* -ENOMEM */
1190 async_cow->inode = igrab(inode);
1191 async_cow->root = root;
1192 async_cow->locked_page = locked_page;
1193 async_cow->start = start;
1194 async_cow->write_flags = write_flags;
1195
1196 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS &&
1197 !btrfs_test_opt(fs_info, FORCE_COMPRESS))
1198 cur_end = end;
1199 else
1200 cur_end = min(end, start + SZ_512K - 1);
1201
1202 async_cow->end = cur_end;
1203 INIT_LIST_HEAD(&async_cow->extents);
1204
1205 btrfs_init_work(&async_cow->work,
1206 btrfs_delalloc_helper,
1207 async_cow_start, async_cow_submit,
1208 async_cow_free);
1209
1210 nr_pages = (cur_end - start + PAGE_SIZE) >>
1211 PAGE_SHIFT;
1212 atomic_add(nr_pages, &fs_info->async_delalloc_pages);
1213
1214 btrfs_queue_work(fs_info->delalloc_workers, &async_cow->work);
1215
1216 *nr_written += nr_pages;
1217 start = cur_end + 1;
1218 }
1219 *page_started = 1;
1220 return 0;
1221 }
1222
1223 static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info,
1224 u64 bytenr, u64 num_bytes)
1225 {
1226 int ret;
1227 struct btrfs_ordered_sum *sums;
1228 LIST_HEAD(list);
1229
1230 ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr,
1231 bytenr + num_bytes - 1, &list, 0);
1232 if (ret == 0 && list_empty(&list))
1233 return 0;
1234
1235 while (!list_empty(&list)) {
1236 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1237 list_del(&sums->list);
1238 kfree(sums);
1239 }
1240 if (ret < 0)
1241 return ret;
1242 return 1;
1243 }
1244
1245 /*
1246 * when nowcow writeback call back. This checks for snapshots or COW copies
1247 * of the extents that exist in the file, and COWs the file as required.
1248 *
1249 * If no cow copies or snapshots exist, we write directly to the existing
1250 * blocks on disk
1251 */
1252 static noinline int run_delalloc_nocow(struct inode *inode,
1253 struct page *locked_page,
1254 u64 start, u64 end, int *page_started, int force,
1255 unsigned long *nr_written)
1256 {
1257 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1258 struct btrfs_root *root = BTRFS_I(inode)->root;
1259 struct extent_buffer *leaf;
1260 struct btrfs_path *path;
1261 struct btrfs_file_extent_item *fi;
1262 struct btrfs_key found_key;
1263 struct extent_map *em;
1264 u64 cow_start;
1265 u64 cur_offset;
1266 u64 extent_end;
1267 u64 extent_offset;
1268 u64 disk_bytenr;
1269 u64 num_bytes;
1270 u64 disk_num_bytes;
1271 u64 ram_bytes;
1272 int extent_type;
1273 int ret;
1274 int type;
1275 int nocow;
1276 int check_prev = 1;
1277 bool nolock;
1278 u64 ino = btrfs_ino(BTRFS_I(inode));
1279
1280 path = btrfs_alloc_path();
1281 if (!path) {
1282 extent_clear_unlock_delalloc(inode, start, end, end,
1283 locked_page,
1284 EXTENT_LOCKED | EXTENT_DELALLOC |
1285 EXTENT_DO_ACCOUNTING |
1286 EXTENT_DEFRAG, PAGE_UNLOCK |
1287 PAGE_CLEAR_DIRTY |
1288 PAGE_SET_WRITEBACK |
1289 PAGE_END_WRITEBACK);
1290 return -ENOMEM;
1291 }
1292
1293 nolock = btrfs_is_free_space_inode(BTRFS_I(inode));
1294
1295 cow_start = (u64)-1;
1296 cur_offset = start;
1297 while (1) {
1298 ret = btrfs_lookup_file_extent(NULL, root, path, ino,
1299 cur_offset, 0);
1300 if (ret < 0)
1301 goto error;
1302 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1303 leaf = path->nodes[0];
1304 btrfs_item_key_to_cpu(leaf, &found_key,
1305 path->slots[0] - 1);
1306 if (found_key.objectid == ino &&
1307 found_key.type == BTRFS_EXTENT_DATA_KEY)
1308 path->slots[0]--;
1309 }
1310 check_prev = 0;
1311 next_slot:
1312 leaf = path->nodes[0];
1313 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1314 ret = btrfs_next_leaf(root, path);
1315 if (ret < 0) {
1316 if (cow_start != (u64)-1)
1317 cur_offset = cow_start;
1318 goto error;
1319 }
1320 if (ret > 0)
1321 break;
1322 leaf = path->nodes[0];
1323 }
1324
1325 nocow = 0;
1326 disk_bytenr = 0;
1327 num_bytes = 0;
1328 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1329
1330 if (found_key.objectid > ino)
1331 break;
1332 if (WARN_ON_ONCE(found_key.objectid < ino) ||
1333 found_key.type < BTRFS_EXTENT_DATA_KEY) {
1334 path->slots[0]++;
1335 goto next_slot;
1336 }
1337 if (found_key.type > BTRFS_EXTENT_DATA_KEY ||
1338 found_key.offset > end)
1339 break;
1340
1341 if (found_key.offset > cur_offset) {
1342 extent_end = found_key.offset;
1343 extent_type = 0;
1344 goto out_check;
1345 }
1346
1347 fi = btrfs_item_ptr(leaf, path->slots[0],
1348 struct btrfs_file_extent_item);
1349 extent_type = btrfs_file_extent_type(leaf, fi);
1350
1351 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1352 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1353 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1354 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1355 extent_offset = btrfs_file_extent_offset(leaf, fi);
1356 extent_end = found_key.offset +
1357 btrfs_file_extent_num_bytes(leaf, fi);
1358 disk_num_bytes =
1359 btrfs_file_extent_disk_num_bytes(leaf, fi);
1360 if (extent_end <= start) {
1361 path->slots[0]++;
1362 goto next_slot;
1363 }
1364 if (disk_bytenr == 0)
1365 goto out_check;
1366 if (btrfs_file_extent_compression(leaf, fi) ||
1367 btrfs_file_extent_encryption(leaf, fi) ||
1368 btrfs_file_extent_other_encoding(leaf, fi))
1369 goto out_check;
1370 /*
1371 * Do the same check as in btrfs_cross_ref_exist but
1372 * without the unnecessary search.
1373 */
1374 if (btrfs_file_extent_generation(leaf, fi) <=
1375 btrfs_root_last_snapshot(&root->root_item))
1376 goto out_check;
1377 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1378 goto out_check;
1379 if (btrfs_extent_readonly(fs_info, disk_bytenr))
1380 goto out_check;
1381 ret = btrfs_cross_ref_exist(root, ino,
1382 found_key.offset -
1383 extent_offset, disk_bytenr);
1384 if (ret) {
1385 /*
1386 * ret could be -EIO if the above fails to read
1387 * metadata.
1388 */
1389 if (ret < 0) {
1390 if (cow_start != (u64)-1)
1391 cur_offset = cow_start;
1392 goto error;
1393 }
1394
1395 WARN_ON_ONCE(nolock);
1396 goto out_check;
1397 }
1398 disk_bytenr += extent_offset;
1399 disk_bytenr += cur_offset - found_key.offset;
1400 num_bytes = min(end + 1, extent_end) - cur_offset;
1401 /*
1402 * if there are pending snapshots for this root,
1403 * we fall into common COW way.
1404 */
1405 if (!nolock && atomic_read(&root->snapshot_force_cow))
1406 goto out_check;
1407 /*
1408 * force cow if csum exists in the range.
1409 * this ensure that csum for a given extent are
1410 * either valid or do not exist.
1411 */
1412 ret = csum_exist_in_range(fs_info, disk_bytenr,
1413 num_bytes);
1414 if (ret) {
1415 /*
1416 * ret could be -EIO if the above fails to read
1417 * metadata.
1418 */
1419 if (ret < 0) {
1420 if (cow_start != (u64)-1)
1421 cur_offset = cow_start;
1422 goto error;
1423 }
1424 WARN_ON_ONCE(nolock);
1425 goto out_check;
1426 }
1427 if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr))
1428 goto out_check;
1429 nocow = 1;
1430 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1431 extent_end = found_key.offset +
1432 btrfs_file_extent_ram_bytes(leaf, fi);
1433 extent_end = ALIGN(extent_end,
1434 fs_info->sectorsize);
1435 } else {
1436 BUG_ON(1);
1437 }
1438 out_check:
1439 if (extent_end <= start) {
1440 path->slots[0]++;
1441 if (nocow)
1442 btrfs_dec_nocow_writers(fs_info, disk_bytenr);
1443 goto next_slot;
1444 }
1445 if (!nocow) {
1446 if (cow_start == (u64)-1)
1447 cow_start = cur_offset;
1448 cur_offset = extent_end;
1449 if (cur_offset > end)
1450 break;
1451 path->slots[0]++;
1452 goto next_slot;
1453 }
1454
1455 btrfs_release_path(path);
1456 if (cow_start != (u64)-1) {
1457 ret = cow_file_range(inode, locked_page,
1458 cow_start, found_key.offset - 1,
1459 end, page_started, nr_written, 1,
1460 NULL);
1461 if (ret) {
1462 if (nocow)
1463 btrfs_dec_nocow_writers(fs_info,
1464 disk_bytenr);
1465 goto error;
1466 }
1467 cow_start = (u64)-1;
1468 }
1469
1470 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1471 u64 orig_start = found_key.offset - extent_offset;
1472
1473 em = create_io_em(inode, cur_offset, num_bytes,
1474 orig_start,
1475 disk_bytenr, /* block_start */
1476 num_bytes, /* block_len */
1477 disk_num_bytes, /* orig_block_len */
1478 ram_bytes, BTRFS_COMPRESS_NONE,
1479 BTRFS_ORDERED_PREALLOC);
1480 if (IS_ERR(em)) {
1481 if (nocow)
1482 btrfs_dec_nocow_writers(fs_info,
1483 disk_bytenr);
1484 ret = PTR_ERR(em);
1485 goto error;
1486 }
1487 free_extent_map(em);
1488 }
1489
1490 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1491 type = BTRFS_ORDERED_PREALLOC;
1492 } else {
1493 type = BTRFS_ORDERED_NOCOW;
1494 }
1495
1496 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1497 num_bytes, num_bytes, type);
1498 if (nocow)
1499 btrfs_dec_nocow_writers(fs_info, disk_bytenr);
1500 BUG_ON(ret); /* -ENOMEM */
1501
1502 if (root->root_key.objectid ==
1503 BTRFS_DATA_RELOC_TREE_OBJECTID)
1504 /*
1505 * Error handled later, as we must prevent
1506 * extent_clear_unlock_delalloc() in error handler
1507 * from freeing metadata of created ordered extent.
1508 */
1509 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1510 num_bytes);
1511
1512 extent_clear_unlock_delalloc(inode, cur_offset,
1513 cur_offset + num_bytes - 1, end,
1514 locked_page, EXTENT_LOCKED |
1515 EXTENT_DELALLOC |
1516 EXTENT_CLEAR_DATA_RESV,
1517 PAGE_UNLOCK | PAGE_SET_PRIVATE2);
1518
1519 cur_offset = extent_end;
1520
1521 /*
1522 * btrfs_reloc_clone_csums() error, now we're OK to call error
1523 * handler, as metadata for created ordered extent will only
1524 * be freed by btrfs_finish_ordered_io().
1525 */
1526 if (ret)
1527 goto error;
1528 if (cur_offset > end)
1529 break;
1530 }
1531 btrfs_release_path(path);
1532
1533 if (cur_offset <= end && cow_start == (u64)-1) {
1534 cow_start = cur_offset;
1535 cur_offset = end;
1536 }
1537
1538 if (cow_start != (u64)-1) {
1539 ret = cow_file_range(inode, locked_page, cow_start, end, end,
1540 page_started, nr_written, 1, NULL);
1541 if (ret)
1542 goto error;
1543 }
1544
1545 error:
1546 if (ret && cur_offset < end)
1547 extent_clear_unlock_delalloc(inode, cur_offset, end, end,
1548 locked_page, EXTENT_LOCKED |
1549 EXTENT_DELALLOC | EXTENT_DEFRAG |
1550 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
1551 PAGE_CLEAR_DIRTY |
1552 PAGE_SET_WRITEBACK |
1553 PAGE_END_WRITEBACK);
1554 btrfs_free_path(path);
1555 return ret;
1556 }
1557
1558 static inline int need_force_cow(struct inode *inode, u64 start, u64 end)
1559 {
1560
1561 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
1562 !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC))
1563 return 0;
1564
1565 /*
1566 * @defrag_bytes is a hint value, no spinlock held here,
1567 * if is not zero, it means the file is defragging.
1568 * Force cow if given extent needs to be defragged.
1569 */
1570 if (BTRFS_I(inode)->defrag_bytes &&
1571 test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
1572 EXTENT_DEFRAG, 0, NULL))
1573 return 1;
1574
1575 return 0;
1576 }
1577
1578 /*
1579 * extent_io.c call back to do delayed allocation processing
1580 */
1581 static int run_delalloc_range(void *private_data, struct page *locked_page,
1582 u64 start, u64 end, int *page_started,
1583 unsigned long *nr_written,
1584 struct writeback_control *wbc)
1585 {
1586 struct inode *inode = private_data;
1587 int ret;
1588 int force_cow = need_force_cow(inode, start, end);
1589 unsigned int write_flags = wbc_to_write_flags(wbc);
1590
1591 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) {
1592 ret = run_delalloc_nocow(inode, locked_page, start, end,
1593 page_started, 1, nr_written);
1594 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) {
1595 ret = run_delalloc_nocow(inode, locked_page, start, end,
1596 page_started, 0, nr_written);
1597 } else if (!inode_need_compress(inode, start, end)) {
1598 ret = cow_file_range(inode, locked_page, start, end, end,
1599 page_started, nr_written, 1, NULL);
1600 } else {
1601 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1602 &BTRFS_I(inode)->runtime_flags);
1603 ret = cow_file_range_async(inode, locked_page, start, end,
1604 page_started, nr_written,
1605 write_flags);
1606 }
1607 if (ret)
1608 btrfs_cleanup_ordered_extents(inode, start, end - start + 1);
1609 return ret;
1610 }
1611
1612 static void btrfs_split_extent_hook(void *private_data,
1613 struct extent_state *orig, u64 split)
1614 {
1615 struct inode *inode = private_data;
1616 u64 size;
1617
1618 /* not delalloc, ignore it */
1619 if (!(orig->state & EXTENT_DELALLOC))
1620 return;
1621
1622 size = orig->end - orig->start + 1;
1623 if (size > BTRFS_MAX_EXTENT_SIZE) {
1624 u32 num_extents;
1625 u64 new_size;
1626
1627 /*
1628 * See the explanation in btrfs_merge_extent_hook, the same
1629 * applies here, just in reverse.
1630 */
1631 new_size = orig->end - split + 1;
1632 num_extents = count_max_extents(new_size);
1633 new_size = split - orig->start;
1634 num_extents += count_max_extents(new_size);
1635 if (count_max_extents(size) >= num_extents)
1636 return;
1637 }
1638
1639 spin_lock(&BTRFS_I(inode)->lock);
1640 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1641 spin_unlock(&BTRFS_I(inode)->lock);
1642 }
1643
1644 /*
1645 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1646 * extents so we can keep track of new extents that are just merged onto old
1647 * extents, such as when we are doing sequential writes, so we can properly
1648 * account for the metadata space we'll need.
1649 */
1650 static void btrfs_merge_extent_hook(void *private_data,
1651 struct extent_state *new,
1652 struct extent_state *other)
1653 {
1654 struct inode *inode = private_data;
1655 u64 new_size, old_size;
1656 u32 num_extents;
1657
1658 /* not delalloc, ignore it */
1659 if (!(other->state & EXTENT_DELALLOC))
1660 return;
1661
1662 if (new->start > other->start)
1663 new_size = new->end - other->start + 1;
1664 else
1665 new_size = other->end - new->start + 1;
1666
1667 /* we're not bigger than the max, unreserve the space and go */
1668 if (new_size <= BTRFS_MAX_EXTENT_SIZE) {
1669 spin_lock(&BTRFS_I(inode)->lock);
1670 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1);
1671 spin_unlock(&BTRFS_I(inode)->lock);
1672 return;
1673 }
1674
1675 /*
1676 * We have to add up either side to figure out how many extents were
1677 * accounted for before we merged into one big extent. If the number of
1678 * extents we accounted for is <= the amount we need for the new range
1679 * then we can return, otherwise drop. Think of it like this
1680 *
1681 * [ 4k][MAX_SIZE]
1682 *
1683 * So we've grown the extent by a MAX_SIZE extent, this would mean we
1684 * need 2 outstanding extents, on one side we have 1 and the other side
1685 * we have 1 so they are == and we can return. But in this case
1686 *
1687 * [MAX_SIZE+4k][MAX_SIZE+4k]
1688 *
1689 * Each range on their own accounts for 2 extents, but merged together
1690 * they are only 3 extents worth of accounting, so we need to drop in
1691 * this case.
1692 */
1693 old_size = other->end - other->start + 1;
1694 num_extents = count_max_extents(old_size);
1695 old_size = new->end - new->start + 1;
1696 num_extents += count_max_extents(old_size);
1697 if (count_max_extents(new_size) >= num_extents)
1698 return;
1699
1700 spin_lock(&BTRFS_I(inode)->lock);
1701 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1);
1702 spin_unlock(&BTRFS_I(inode)->lock);
1703 }
1704
1705 static void btrfs_add_delalloc_inodes(struct btrfs_root *root,
1706 struct inode *inode)
1707 {
1708 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1709
1710 spin_lock(&root->delalloc_lock);
1711 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1712 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1713 &root->delalloc_inodes);
1714 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1715 &BTRFS_I(inode)->runtime_flags);
1716 root->nr_delalloc_inodes++;
1717 if (root->nr_delalloc_inodes == 1) {
1718 spin_lock(&fs_info->delalloc_root_lock);
1719 BUG_ON(!list_empty(&root->delalloc_root));
1720 list_add_tail(&root->delalloc_root,
1721 &fs_info->delalloc_roots);
1722 spin_unlock(&fs_info->delalloc_root_lock);
1723 }
1724 }
1725 spin_unlock(&root->delalloc_lock);
1726 }
1727
1728
1729 void __btrfs_del_delalloc_inode(struct btrfs_root *root,
1730 struct btrfs_inode *inode)
1731 {
1732 struct btrfs_fs_info *fs_info = root->fs_info;
1733
1734 if (!list_empty(&inode->delalloc_inodes)) {
1735 list_del_init(&inode->delalloc_inodes);
1736 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1737 &inode->runtime_flags);
1738 root->nr_delalloc_inodes--;
1739 if (!root->nr_delalloc_inodes) {
1740 ASSERT(list_empty(&root->delalloc_inodes));
1741 spin_lock(&fs_info->delalloc_root_lock);
1742 BUG_ON(list_empty(&root->delalloc_root));
1743 list_del_init(&root->delalloc_root);
1744 spin_unlock(&fs_info->delalloc_root_lock);
1745 }
1746 }
1747 }
1748
1749 static void btrfs_del_delalloc_inode(struct btrfs_root *root,
1750 struct btrfs_inode *inode)
1751 {
1752 spin_lock(&root->delalloc_lock);
1753 __btrfs_del_delalloc_inode(root, inode);
1754 spin_unlock(&root->delalloc_lock);
1755 }
1756
1757 /*
1758 * extent_io.c set_bit_hook, used to track delayed allocation
1759 * bytes in this file, and to maintain the list of inodes that
1760 * have pending delalloc work to be done.
1761 */
1762 static void btrfs_set_bit_hook(void *private_data,
1763 struct extent_state *state, unsigned *bits)
1764 {
1765 struct inode *inode = private_data;
1766
1767 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1768
1769 if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC))
1770 WARN_ON(1);
1771 /*
1772 * set_bit and clear bit hooks normally require _irqsave/restore
1773 * but in this case, we are only testing for the DELALLOC
1774 * bit, which is only set or cleared with irqs on
1775 */
1776 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1777 struct btrfs_root *root = BTRFS_I(inode)->root;
1778 u64 len = state->end + 1 - state->start;
1779 u32 num_extents = count_max_extents(len);
1780 bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode));
1781
1782 spin_lock(&BTRFS_I(inode)->lock);
1783 btrfs_mod_outstanding_extents(BTRFS_I(inode), num_extents);
1784 spin_unlock(&BTRFS_I(inode)->lock);
1785
1786 /* For sanity tests */
1787 if (btrfs_is_testing(fs_info))
1788 return;
1789
1790 percpu_counter_add_batch(&fs_info->delalloc_bytes, len,
1791 fs_info->delalloc_batch);
1792 spin_lock(&BTRFS_I(inode)->lock);
1793 BTRFS_I(inode)->delalloc_bytes += len;
1794 if (*bits & EXTENT_DEFRAG)
1795 BTRFS_I(inode)->defrag_bytes += len;
1796 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1797 &BTRFS_I(inode)->runtime_flags))
1798 btrfs_add_delalloc_inodes(root, inode);
1799 spin_unlock(&BTRFS_I(inode)->lock);
1800 }
1801
1802 if (!(state->state & EXTENT_DELALLOC_NEW) &&
1803 (*bits & EXTENT_DELALLOC_NEW)) {
1804 spin_lock(&BTRFS_I(inode)->lock);
1805 BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 -
1806 state->start;
1807 spin_unlock(&BTRFS_I(inode)->lock);
1808 }
1809 }
1810
1811 /*
1812 * extent_io.c clear_bit_hook, see set_bit_hook for why
1813 */
1814 static void btrfs_clear_bit_hook(void *private_data,
1815 struct extent_state *state,
1816 unsigned *bits)
1817 {
1818 struct btrfs_inode *inode = BTRFS_I((struct inode *)private_data);
1819 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
1820 u64 len = state->end + 1 - state->start;
1821 u32 num_extents = count_max_extents(len);
1822
1823 if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) {
1824 spin_lock(&inode->lock);
1825 inode->defrag_bytes -= len;
1826 spin_unlock(&inode->lock);
1827 }
1828
1829 /*
1830 * set_bit and clear bit hooks normally require _irqsave/restore
1831 * but in this case, we are only testing for the DELALLOC
1832 * bit, which is only set or cleared with irqs on
1833 */
1834 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1835 struct btrfs_root *root = inode->root;
1836 bool do_list = !btrfs_is_free_space_inode(inode);
1837
1838 spin_lock(&inode->lock);
1839 btrfs_mod_outstanding_extents(inode, -num_extents);
1840 spin_unlock(&inode->lock);
1841
1842 /*
1843 * We don't reserve metadata space for space cache inodes so we
1844 * don't need to call dellalloc_release_metadata if there is an
1845 * error.
1846 */
1847 if (*bits & EXTENT_CLEAR_META_RESV &&
1848 root != fs_info->tree_root)
1849 btrfs_delalloc_release_metadata(inode, len, false);
1850
1851 /* For sanity tests. */
1852 if (btrfs_is_testing(fs_info))
1853 return;
1854
1855 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID &&
1856 do_list && !(state->state & EXTENT_NORESERVE) &&
1857 (*bits & EXTENT_CLEAR_DATA_RESV))
1858 btrfs_free_reserved_data_space_noquota(
1859 &inode->vfs_inode,
1860 state->start, len);
1861
1862 percpu_counter_add_batch(&fs_info->delalloc_bytes, -len,
1863 fs_info->delalloc_batch);
1864 spin_lock(&inode->lock);
1865 inode->delalloc_bytes -= len;
1866 if (do_list && inode->delalloc_bytes == 0 &&
1867 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1868 &inode->runtime_flags))
1869 btrfs_del_delalloc_inode(root, inode);
1870 spin_unlock(&inode->lock);
1871 }
1872
1873 if ((state->state & EXTENT_DELALLOC_NEW) &&
1874 (*bits & EXTENT_DELALLOC_NEW)) {
1875 spin_lock(&inode->lock);
1876 ASSERT(inode->new_delalloc_bytes >= len);
1877 inode->new_delalloc_bytes -= len;
1878 spin_unlock(&inode->lock);
1879 }
1880 }
1881
1882 /*
1883 * Merge bio hook, this must check the chunk tree to make sure we don't create
1884 * bios that span stripes or chunks
1885 *
1886 * return 1 if page cannot be merged to bio
1887 * return 0 if page can be merged to bio
1888 * return error otherwise
1889 */
1890 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1891 size_t size, struct bio *bio,
1892 unsigned long bio_flags)
1893 {
1894 struct inode *inode = page->mapping->host;
1895 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1896 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
1897 u64 length = 0;
1898 u64 map_length;
1899 int ret;
1900
1901 if (bio_flags & EXTENT_BIO_COMPRESSED)
1902 return 0;
1903
1904 length = bio->bi_iter.bi_size;
1905 map_length = length;
1906 ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
1907 NULL, 0);
1908 if (ret < 0)
1909 return ret;
1910 if (map_length < length + size)
1911 return 1;
1912 return 0;
1913 }
1914
1915 /*
1916 * in order to insert checksums into the metadata in large chunks,
1917 * we wait until bio submission time. All the pages in the bio are
1918 * checksummed and sums are attached onto the ordered extent record.
1919 *
1920 * At IO completion time the cums attached on the ordered extent record
1921 * are inserted into the btree
1922 */
1923 static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio,
1924 u64 bio_offset)
1925 {
1926 struct inode *inode = private_data;
1927 blk_status_t ret = 0;
1928
1929 ret = btrfs_csum_one_bio(inode, bio, 0, 0);
1930 BUG_ON(ret); /* -ENOMEM */
1931 return 0;
1932 }
1933
1934 /*
1935 * in order to insert checksums into the metadata in large chunks,
1936 * we wait until bio submission time. All the pages in the bio are
1937 * checksummed and sums are attached onto the ordered extent record.
1938 *
1939 * At IO completion time the cums attached on the ordered extent record
1940 * are inserted into the btree
1941 */
1942 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
1943 int mirror_num)
1944 {
1945 struct inode *inode = private_data;
1946 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1947 blk_status_t ret;
1948
1949 ret = btrfs_map_bio(fs_info, bio, mirror_num, 1);
1950 if (ret) {
1951 bio->bi_status = ret;
1952 bio_endio(bio);
1953 }
1954 return ret;
1955 }
1956
1957 /*
1958 * extent_io.c submission hook. This does the right thing for csum calculation
1959 * on write, or reading the csums from the tree before a read.
1960 *
1961 * Rules about async/sync submit,
1962 * a) read: sync submit
1963 *
1964 * b) write without checksum: sync submit
1965 *
1966 * c) write with checksum:
1967 * c-1) if bio is issued by fsync: sync submit
1968 * (sync_writers != 0)
1969 *
1970 * c-2) if root is reloc root: sync submit
1971 * (only in case of buffered IO)
1972 *
1973 * c-3) otherwise: async submit
1974 */
1975 static blk_status_t btrfs_submit_bio_hook(void *private_data, struct bio *bio,
1976 int mirror_num, unsigned long bio_flags,
1977 u64 bio_offset)
1978 {
1979 struct inode *inode = private_data;
1980 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1981 struct btrfs_root *root = BTRFS_I(inode)->root;
1982 enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA;
1983 blk_status_t ret = 0;
1984 int skip_sum;
1985 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
1986
1987 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1988
1989 if (btrfs_is_free_space_inode(BTRFS_I(inode)))
1990 metadata = BTRFS_WQ_ENDIO_FREE_SPACE;
1991
1992 if (bio_op(bio) != REQ_OP_WRITE) {
1993 ret = btrfs_bio_wq_end_io(fs_info, bio, metadata);
1994 if (ret)
1995 goto out;
1996
1997 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1998 ret = btrfs_submit_compressed_read(inode, bio,
1999 mirror_num,
2000 bio_flags);
2001 goto out;
2002 } else if (!skip_sum) {
2003 ret = btrfs_lookup_bio_sums(inode, bio, NULL);
2004 if (ret)
2005 goto out;
2006 }
2007 goto mapit;
2008 } else if (async && !skip_sum) {
2009 /* csum items have already been cloned */
2010 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2011 goto mapit;
2012 /* we're doing a write, do the async checksumming */
2013 ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags,
2014 bio_offset, inode,
2015 btrfs_submit_bio_start);
2016 goto out;
2017 } else if (!skip_sum) {
2018 ret = btrfs_csum_one_bio(inode, bio, 0, 0);
2019 if (ret)
2020 goto out;
2021 }
2022
2023 mapit:
2024 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
2025
2026 out:
2027 if (ret) {
2028 bio->bi_status = ret;
2029 bio_endio(bio);
2030 }
2031 return ret;
2032 }
2033
2034 /*
2035 * given a list of ordered sums record them in the inode. This happens
2036 * at IO completion time based on sums calculated at bio submission time.
2037 */
2038 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
2039 struct inode *inode, struct list_head *list)
2040 {
2041 struct btrfs_ordered_sum *sum;
2042 int ret;
2043
2044 list_for_each_entry(sum, list, list) {
2045 trans->adding_csums = true;
2046 ret = btrfs_csum_file_blocks(trans,
2047 BTRFS_I(inode)->root->fs_info->csum_root, sum);
2048 trans->adding_csums = false;
2049 if (ret)
2050 return ret;
2051 }
2052 return 0;
2053 }
2054
2055 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
2056 unsigned int extra_bits,
2057 struct extent_state **cached_state, int dedupe)
2058 {
2059 WARN_ON((end & (PAGE_SIZE - 1)) == 0);
2060 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
2061 extra_bits, cached_state);
2062 }
2063
2064 /* see btrfs_writepage_start_hook for details on why this is required */
2065 struct btrfs_writepage_fixup {
2066 struct page *page;
2067 struct btrfs_work work;
2068 };
2069
2070 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
2071 {
2072 struct btrfs_writepage_fixup *fixup;
2073 struct btrfs_ordered_extent *ordered;
2074 struct extent_state *cached_state = NULL;
2075 struct extent_changeset *data_reserved = NULL;
2076 struct page *page;
2077 struct inode *inode;
2078 u64 page_start;
2079 u64 page_end;
2080 int ret;
2081
2082 fixup = container_of(work, struct btrfs_writepage_fixup, work);
2083 page = fixup->page;
2084 again:
2085 lock_page(page);
2086 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
2087 ClearPageChecked(page);
2088 goto out_page;
2089 }
2090
2091 inode = page->mapping->host;
2092 page_start = page_offset(page);
2093 page_end = page_offset(page) + PAGE_SIZE - 1;
2094
2095 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
2096 &cached_state);
2097
2098 /* already ordered? We're done */
2099 if (PagePrivate2(page))
2100 goto out;
2101
2102 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
2103 PAGE_SIZE);
2104 if (ordered) {
2105 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
2106 page_end, &cached_state);
2107 unlock_page(page);
2108 btrfs_start_ordered_extent(inode, ordered, 1);
2109 btrfs_put_ordered_extent(ordered);
2110 goto again;
2111 }
2112
2113 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
2114 PAGE_SIZE);
2115 if (ret) {
2116 mapping_set_error(page->mapping, ret);
2117 end_extent_writepage(page, ret, page_start, page_end);
2118 ClearPageChecked(page);
2119 goto out;
2120 }
2121
2122 ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0,
2123 &cached_state, 0);
2124 if (ret) {
2125 mapping_set_error(page->mapping, ret);
2126 end_extent_writepage(page, ret, page_start, page_end);
2127 ClearPageChecked(page);
2128 goto out;
2129 }
2130
2131 ClearPageChecked(page);
2132 set_page_dirty(page);
2133 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, false);
2134 out:
2135 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
2136 &cached_state);
2137 out_page:
2138 unlock_page(page);
2139 put_page(page);
2140 kfree(fixup);
2141 extent_changeset_free(data_reserved);
2142 }
2143
2144 /*
2145 * There are a few paths in the higher layers of the kernel that directly
2146 * set the page dirty bit without asking the filesystem if it is a
2147 * good idea. This causes problems because we want to make sure COW
2148 * properly happens and the data=ordered rules are followed.
2149 *
2150 * In our case any range that doesn't have the ORDERED bit set
2151 * hasn't been properly setup for IO. We kick off an async process
2152 * to fix it up. The async helper will wait for ordered extents, set
2153 * the delalloc bit and make it safe to write the page.
2154 */
2155 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
2156 {
2157 struct inode *inode = page->mapping->host;
2158 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2159 struct btrfs_writepage_fixup *fixup;
2160
2161 /* this page is properly in the ordered list */
2162 if (TestClearPagePrivate2(page))
2163 return 0;
2164
2165 if (PageChecked(page))
2166 return -EAGAIN;
2167
2168 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
2169 if (!fixup)
2170 return -EAGAIN;
2171
2172 SetPageChecked(page);
2173 get_page(page);
2174 btrfs_init_work(&fixup->work, btrfs_fixup_helper,
2175 btrfs_writepage_fixup_worker, NULL, NULL);
2176 fixup->page = page;
2177 btrfs_queue_work(fs_info->fixup_workers, &fixup->work);
2178 return -EBUSY;
2179 }
2180
2181 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
2182 struct inode *inode, u64 file_pos,
2183 u64 disk_bytenr, u64 disk_num_bytes,
2184 u64 num_bytes, u64 ram_bytes,
2185 u8 compression, u8 encryption,
2186 u16 other_encoding, int extent_type)
2187 {
2188 struct btrfs_root *root = BTRFS_I(inode)->root;
2189 struct btrfs_file_extent_item *fi;
2190 struct btrfs_path *path;
2191 struct extent_buffer *leaf;
2192 struct btrfs_key ins;
2193 u64 qg_released;
2194 int extent_inserted = 0;
2195 int ret;
2196
2197 path = btrfs_alloc_path();
2198 if (!path)
2199 return -ENOMEM;
2200
2201 /*
2202 * we may be replacing one extent in the tree with another.
2203 * The new extent is pinned in the extent map, and we don't want
2204 * to drop it from the cache until it is completely in the btree.
2205 *
2206 * So, tell btrfs_drop_extents to leave this extent in the cache.
2207 * the caller is expected to unpin it and allow it to be merged
2208 * with the others.
2209 */
2210 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos,
2211 file_pos + num_bytes, NULL, 0,
2212 1, sizeof(*fi), &extent_inserted);
2213 if (ret)
2214 goto out;
2215
2216 if (!extent_inserted) {
2217 ins.objectid = btrfs_ino(BTRFS_I(inode));
2218 ins.offset = file_pos;
2219 ins.type = BTRFS_EXTENT_DATA_KEY;
2220
2221 path->leave_spinning = 1;
2222 ret = btrfs_insert_empty_item(trans, root, path, &ins,
2223 sizeof(*fi));
2224 if (ret)
2225 goto out;
2226 }
2227 leaf = path->nodes[0];
2228 fi = btrfs_item_ptr(leaf, path->slots[0],
2229 struct btrfs_file_extent_item);
2230 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
2231 btrfs_set_file_extent_type(leaf, fi, extent_type);
2232 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
2233 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
2234 btrfs_set_file_extent_offset(leaf, fi, 0);
2235 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
2236 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
2237 btrfs_set_file_extent_compression(leaf, fi, compression);
2238 btrfs_set_file_extent_encryption(leaf, fi, encryption);
2239 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
2240
2241 btrfs_mark_buffer_dirty(leaf);
2242 btrfs_release_path(path);
2243
2244 inode_add_bytes(inode, num_bytes);
2245
2246 ins.objectid = disk_bytenr;
2247 ins.offset = disk_num_bytes;
2248 ins.type = BTRFS_EXTENT_ITEM_KEY;
2249
2250 /*
2251 * Release the reserved range from inode dirty range map, as it is
2252 * already moved into delayed_ref_head
2253 */
2254 ret = btrfs_qgroup_release_data(inode, file_pos, ram_bytes);
2255 if (ret < 0)
2256 goto out;
2257 qg_released = ret;
2258 ret = btrfs_alloc_reserved_file_extent(trans, root,
2259 btrfs_ino(BTRFS_I(inode)),
2260 file_pos, qg_released, &ins);
2261 out:
2262 btrfs_free_path(path);
2263
2264 return ret;
2265 }
2266
2267 /* snapshot-aware defrag */
2268 struct sa_defrag_extent_backref {
2269 struct rb_node node;
2270 struct old_sa_defrag_extent *old;
2271 u64 root_id;
2272 u64 inum;
2273 u64 file_pos;
2274 u64 extent_offset;
2275 u64 num_bytes;
2276 u64 generation;
2277 };
2278
2279 struct old_sa_defrag_extent {
2280 struct list_head list;
2281 struct new_sa_defrag_extent *new;
2282
2283 u64 extent_offset;
2284 u64 bytenr;
2285 u64 offset;
2286 u64 len;
2287 int count;
2288 };
2289
2290 struct new_sa_defrag_extent {
2291 struct rb_root root;
2292 struct list_head head;
2293 struct btrfs_path *path;
2294 struct inode *inode;
2295 u64 file_pos;
2296 u64 len;
2297 u64 bytenr;
2298 u64 disk_len;
2299 u8 compress_type;
2300 };
2301
2302 static int backref_comp(struct sa_defrag_extent_backref *b1,
2303 struct sa_defrag_extent_backref *b2)
2304 {
2305 if (b1->root_id < b2->root_id)
2306 return -1;
2307 else if (b1->root_id > b2->root_id)
2308 return 1;
2309
2310 if (b1->inum < b2->inum)
2311 return -1;
2312 else if (b1->inum > b2->inum)
2313 return 1;
2314
2315 if (b1->file_pos < b2->file_pos)
2316 return -1;
2317 else if (b1->file_pos > b2->file_pos)
2318 return 1;
2319
2320 /*
2321 * [------------------------------] ===> (a range of space)
2322 * |<--->| |<---->| =============> (fs/file tree A)
2323 * |<---------------------------->| ===> (fs/file tree B)
2324 *
2325 * A range of space can refer to two file extents in one tree while
2326 * refer to only one file extent in another tree.
2327 *
2328 * So we may process a disk offset more than one time(two extents in A)
2329 * and locate at the same extent(one extent in B), then insert two same
2330 * backrefs(both refer to the extent in B).
2331 */
2332 return 0;
2333 }
2334
2335 static void backref_insert(struct rb_root *root,
2336 struct sa_defrag_extent_backref *backref)
2337 {
2338 struct rb_node **p = &root->rb_node;
2339 struct rb_node *parent = NULL;
2340 struct sa_defrag_extent_backref *entry;
2341 int ret;
2342
2343 while (*p) {
2344 parent = *p;
2345 entry = rb_entry(parent, struct sa_defrag_extent_backref, node);
2346
2347 ret = backref_comp(backref, entry);
2348 if (ret < 0)
2349 p = &(*p)->rb_left;
2350 else
2351 p = &(*p)->rb_right;
2352 }
2353
2354 rb_link_node(&backref->node, parent, p);
2355 rb_insert_color(&backref->node, root);
2356 }
2357
2358 /*
2359 * Note the backref might has changed, and in this case we just return 0.
2360 */
2361 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id,
2362 void *ctx)
2363 {
2364 struct btrfs_file_extent_item *extent;
2365 struct old_sa_defrag_extent *old = ctx;
2366 struct new_sa_defrag_extent *new = old->new;
2367 struct btrfs_path *path = new->path;
2368 struct btrfs_key key;
2369 struct btrfs_root *root;
2370 struct sa_defrag_extent_backref *backref;
2371 struct extent_buffer *leaf;
2372 struct inode *inode = new->inode;
2373 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2374 int slot;
2375 int ret;
2376 u64 extent_offset;
2377 u64 num_bytes;
2378
2379 if (BTRFS_I(inode)->root->root_key.objectid == root_id &&
2380 inum == btrfs_ino(BTRFS_I(inode)))
2381 return 0;
2382
2383 key.objectid = root_id;
2384 key.type = BTRFS_ROOT_ITEM_KEY;
2385 key.offset = (u64)-1;
2386
2387 root = btrfs_read_fs_root_no_name(fs_info, &key);
2388 if (IS_ERR(root)) {
2389 if (PTR_ERR(root) == -ENOENT)
2390 return 0;
2391 WARN_ON(1);
2392 btrfs_debug(fs_info, "inum=%llu, offset=%llu, root_id=%llu",
2393 inum, offset, root_id);
2394 return PTR_ERR(root);
2395 }
2396
2397 key.objectid = inum;
2398 key.type = BTRFS_EXTENT_DATA_KEY;
2399 if (offset > (u64)-1 << 32)
2400 key.offset = 0;
2401 else
2402 key.offset = offset;
2403
2404 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2405 if (WARN_ON(ret < 0))
2406 return ret;
2407 ret = 0;
2408
2409 while (1) {
2410 cond_resched();
2411
2412 leaf = path->nodes[0];
2413 slot = path->slots[0];
2414
2415 if (slot >= btrfs_header_nritems(leaf)) {
2416 ret = btrfs_next_leaf(root, path);
2417 if (ret < 0) {
2418 goto out;
2419 } else if (ret > 0) {
2420 ret = 0;
2421 goto out;
2422 }
2423 continue;
2424 }
2425
2426 path->slots[0]++;
2427
2428 btrfs_item_key_to_cpu(leaf, &key, slot);
2429
2430 if (key.objectid > inum)
2431 goto out;
2432
2433 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY)
2434 continue;
2435
2436 extent = btrfs_item_ptr(leaf, slot,
2437 struct btrfs_file_extent_item);
2438
2439 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr)
2440 continue;
2441
2442 /*
2443 * 'offset' refers to the exact key.offset,
2444 * NOT the 'offset' field in btrfs_extent_data_ref, ie.
2445 * (key.offset - extent_offset).
2446 */
2447 if (key.offset != offset)
2448 continue;
2449
2450 extent_offset = btrfs_file_extent_offset(leaf, extent);
2451 num_bytes = btrfs_file_extent_num_bytes(leaf, extent);
2452
2453 if (extent_offset >= old->extent_offset + old->offset +
2454 old->len || extent_offset + num_bytes <=
2455 old->extent_offset + old->offset)
2456 continue;
2457 break;
2458 }
2459
2460 backref = kmalloc(sizeof(*backref), GFP_NOFS);
2461 if (!backref) {
2462 ret = -ENOENT;
2463 goto out;
2464 }
2465
2466 backref->root_id = root_id;
2467 backref->inum = inum;
2468 backref->file_pos = offset;
2469 backref->num_bytes = num_bytes;
2470 backref->extent_offset = extent_offset;
2471 backref->generation = btrfs_file_extent_generation(leaf, extent);
2472 backref->old = old;
2473 backref_insert(&new->root, backref);
2474 old->count++;
2475 out:
2476 btrfs_release_path(path);
2477 WARN_ON(ret);
2478 return ret;
2479 }
2480
2481 static noinline bool record_extent_backrefs(struct btrfs_path *path,
2482 struct new_sa_defrag_extent *new)
2483 {
2484 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb);
2485 struct old_sa_defrag_extent *old, *tmp;
2486 int ret;
2487
2488 new->path = path;
2489
2490 list_for_each_entry_safe(old, tmp, &new->head, list) {
2491 ret = iterate_inodes_from_logical(old->bytenr +
2492 old->extent_offset, fs_info,
2493 path, record_one_backref,
2494 old, false);
2495 if (ret < 0 && ret != -ENOENT)
2496 return false;
2497
2498 /* no backref to be processed for this extent */
2499 if (!old->count) {
2500 list_del(&old->list);
2501 kfree(old);
2502 }
2503 }
2504
2505 if (list_empty(&new->head))
2506 return false;
2507
2508 return true;
2509 }
2510
2511 static int relink_is_mergable(struct extent_buffer *leaf,
2512 struct btrfs_file_extent_item *fi,
2513 struct new_sa_defrag_extent *new)
2514 {
2515 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr)
2516 return 0;
2517
2518 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2519 return 0;
2520
2521 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type)
2522 return 0;
2523
2524 if (btrfs_file_extent_encryption(leaf, fi) ||
2525 btrfs_file_extent_other_encoding(leaf, fi))
2526 return 0;
2527
2528 return 1;
2529 }
2530
2531 /*
2532 * Note the backref might has changed, and in this case we just return 0.
2533 */
2534 static noinline int relink_extent_backref(struct btrfs_path *path,
2535 struct sa_defrag_extent_backref *prev,
2536 struct sa_defrag_extent_backref *backref)
2537 {
2538 struct btrfs_file_extent_item *extent;
2539 struct btrfs_file_extent_item *item;
2540 struct btrfs_ordered_extent *ordered;
2541 struct btrfs_trans_handle *trans;
2542 struct btrfs_root *root;
2543 struct btrfs_key key;
2544 struct extent_buffer *leaf;
2545 struct old_sa_defrag_extent *old = backref->old;
2546 struct new_sa_defrag_extent *new = old->new;
2547 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb);
2548 struct inode *inode;
2549 struct extent_state *cached = NULL;
2550 int ret = 0;
2551 u64 start;
2552 u64 len;
2553 u64 lock_start;
2554 u64 lock_end;
2555 bool merge = false;
2556 int index;
2557
2558 if (prev && prev->root_id == backref->root_id &&
2559 prev->inum == backref->inum &&
2560 prev->file_pos + prev->num_bytes == backref->file_pos)
2561 merge = true;
2562
2563 /* step 1: get root */
2564 key.objectid = backref->root_id;
2565 key.type = BTRFS_ROOT_ITEM_KEY;
2566 key.offset = (u64)-1;
2567
2568 index = srcu_read_lock(&fs_info->subvol_srcu);
2569
2570 root = btrfs_read_fs_root_no_name(fs_info, &key);
2571 if (IS_ERR(root)) {
2572 srcu_read_unlock(&fs_info->subvol_srcu, index);
2573 if (PTR_ERR(root) == -ENOENT)
2574 return 0;
2575 return PTR_ERR(root);
2576 }
2577
2578 if (btrfs_root_readonly(root)) {
2579 srcu_read_unlock(&fs_info->subvol_srcu, index);
2580 return 0;
2581 }
2582
2583 /* step 2: get inode */
2584 key.objectid = backref->inum;
2585 key.type = BTRFS_INODE_ITEM_KEY;
2586 key.offset = 0;
2587
2588 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2589 if (IS_ERR(inode)) {
2590 srcu_read_unlock(&fs_info->subvol_srcu, index);
2591 return 0;
2592 }
2593
2594 srcu_read_unlock(&fs_info->subvol_srcu, index);
2595
2596 /* step 3: relink backref */
2597 lock_start = backref->file_pos;
2598 lock_end = backref->file_pos + backref->num_bytes - 1;
2599 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2600 &cached);
2601
2602 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2603 if (ordered) {
2604 btrfs_put_ordered_extent(ordered);
2605 goto out_unlock;
2606 }
2607
2608 trans = btrfs_join_transaction(root);
2609 if (IS_ERR(trans)) {
2610 ret = PTR_ERR(trans);
2611 goto out_unlock;
2612 }
2613
2614 key.objectid = backref->inum;
2615 key.type = BTRFS_EXTENT_DATA_KEY;
2616 key.offset = backref->file_pos;
2617
2618 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2619 if (ret < 0) {
2620 goto out_free_path;
2621 } else if (ret > 0) {
2622 ret = 0;
2623 goto out_free_path;
2624 }
2625
2626 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2627 struct btrfs_file_extent_item);
2628
2629 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2630 backref->generation)
2631 goto out_free_path;
2632
2633 btrfs_release_path(path);
2634
2635 start = backref->file_pos;
2636 if (backref->extent_offset < old->extent_offset + old->offset)
2637 start += old->extent_offset + old->offset -
2638 backref->extent_offset;
2639
2640 len = min(backref->extent_offset + backref->num_bytes,
2641 old->extent_offset + old->offset + old->len);
2642 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2643
2644 ret = btrfs_drop_extents(trans, root, inode, start,
2645 start + len, 1);
2646 if (ret)
2647 goto out_free_path;
2648 again:
2649 key.objectid = btrfs_ino(BTRFS_I(inode));
2650 key.type = BTRFS_EXTENT_DATA_KEY;
2651 key.offset = start;
2652
2653 path->leave_spinning = 1;
2654 if (merge) {
2655 struct btrfs_file_extent_item *fi;
2656 u64 extent_len;
2657 struct btrfs_key found_key;
2658
2659 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2660 if (ret < 0)
2661 goto out_free_path;
2662
2663 path->slots[0]--;
2664 leaf = path->nodes[0];
2665 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2666
2667 fi = btrfs_item_ptr(leaf, path->slots[0],
2668 struct btrfs_file_extent_item);
2669 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2670
2671 if (extent_len + found_key.offset == start &&
2672 relink_is_mergable(leaf, fi, new)) {
2673 btrfs_set_file_extent_num_bytes(leaf, fi,
2674 extent_len + len);
2675 btrfs_mark_buffer_dirty(leaf);
2676 inode_add_bytes(inode, len);
2677
2678 ret = 1;
2679 goto out_free_path;
2680 } else {
2681 merge = false;
2682 btrfs_release_path(path);
2683 goto again;
2684 }
2685 }
2686
2687 ret = btrfs_insert_empty_item(trans, root, path, &key,
2688 sizeof(*extent));
2689 if (ret) {
2690 btrfs_abort_transaction(trans, ret);
2691 goto out_free_path;
2692 }
2693
2694 leaf = path->nodes[0];
2695 item = btrfs_item_ptr(leaf, path->slots[0],
2696 struct btrfs_file_extent_item);
2697 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2698 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2699 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2700 btrfs_set_file_extent_num_bytes(leaf, item, len);
2701 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2702 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2703 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2704 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2705 btrfs_set_file_extent_encryption(leaf, item, 0);
2706 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2707
2708 btrfs_mark_buffer_dirty(leaf);
2709 inode_add_bytes(inode, len);
2710 btrfs_release_path(path);
2711
2712 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2713 new->disk_len, 0,
2714 backref->root_id, backref->inum,
2715 new->file_pos); /* start - extent_offset */
2716 if (ret) {
2717 btrfs_abort_transaction(trans, ret);
2718 goto out_free_path;
2719 }
2720
2721 ret = 1;
2722 out_free_path:
2723 btrfs_release_path(path);
2724 path->leave_spinning = 0;
2725 btrfs_end_transaction(trans);
2726 out_unlock:
2727 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2728 &cached);
2729 iput(inode);
2730 return ret;
2731 }
2732
2733 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new)
2734 {
2735 struct old_sa_defrag_extent *old, *tmp;
2736
2737 if (!new)
2738 return;
2739
2740 list_for_each_entry_safe(old, tmp, &new->head, list) {
2741 kfree(old);
2742 }
2743 kfree(new);
2744 }
2745
2746 static void relink_file_extents(struct new_sa_defrag_extent *new)
2747 {
2748 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb);
2749 struct btrfs_path *path;
2750 struct sa_defrag_extent_backref *backref;
2751 struct sa_defrag_extent_backref *prev = NULL;
2752 struct rb_node *node;
2753 int ret;
2754
2755 path = btrfs_alloc_path();
2756 if (!path)
2757 return;
2758
2759 if (!record_extent_backrefs(path, new)) {
2760 btrfs_free_path(path);
2761 goto out;
2762 }
2763 btrfs_release_path(path);
2764
2765 while (1) {
2766 node = rb_first(&new->root);
2767 if (!node)
2768 break;
2769 rb_erase(node, &new->root);
2770
2771 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2772
2773 ret = relink_extent_backref(path, prev, backref);
2774 WARN_ON(ret < 0);
2775
2776 kfree(prev);
2777
2778 if (ret == 1)
2779 prev = backref;
2780 else
2781 prev = NULL;
2782 cond_resched();
2783 }
2784 kfree(prev);
2785
2786 btrfs_free_path(path);
2787 out:
2788 free_sa_defrag_extent(new);
2789
2790 atomic_dec(&fs_info->defrag_running);
2791 wake_up(&fs_info->transaction_wait);
2792 }
2793
2794 static struct new_sa_defrag_extent *
2795 record_old_file_extents(struct inode *inode,
2796 struct btrfs_ordered_extent *ordered)
2797 {
2798 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2799 struct btrfs_root *root = BTRFS_I(inode)->root;
2800 struct btrfs_path *path;
2801 struct btrfs_key key;
2802 struct old_sa_defrag_extent *old;
2803 struct new_sa_defrag_extent *new;
2804 int ret;
2805
2806 new = kmalloc(sizeof(*new), GFP_NOFS);
2807 if (!new)
2808 return NULL;
2809
2810 new->inode = inode;
2811 new->file_pos = ordered->file_offset;
2812 new->len = ordered->len;
2813 new->bytenr = ordered->start;
2814 new->disk_len = ordered->disk_len;
2815 new->compress_type = ordered->compress_type;
2816 new->root = RB_ROOT;
2817 INIT_LIST_HEAD(&new->head);
2818
2819 path = btrfs_alloc_path();
2820 if (!path)
2821 goto out_kfree;
2822
2823 key.objectid = btrfs_ino(BTRFS_I(inode));
2824 key.type = BTRFS_EXTENT_DATA_KEY;
2825 key.offset = new->file_pos;
2826
2827 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2828 if (ret < 0)
2829 goto out_free_path;
2830 if (ret > 0 && path->slots[0] > 0)
2831 path->slots[0]--;
2832
2833 /* find out all the old extents for the file range */
2834 while (1) {
2835 struct btrfs_file_extent_item *extent;
2836 struct extent_buffer *l;
2837 int slot;
2838 u64 num_bytes;
2839 u64 offset;
2840 u64 end;
2841 u64 disk_bytenr;
2842 u64 extent_offset;
2843
2844 l = path->nodes[0];
2845 slot = path->slots[0];
2846
2847 if (slot >= btrfs_header_nritems(l)) {
2848 ret = btrfs_next_leaf(root, path);
2849 if (ret < 0)
2850 goto out_free_path;
2851 else if (ret > 0)
2852 break;
2853 continue;
2854 }
2855
2856 btrfs_item_key_to_cpu(l, &key, slot);
2857
2858 if (key.objectid != btrfs_ino(BTRFS_I(inode)))
2859 break;
2860 if (key.type != BTRFS_EXTENT_DATA_KEY)
2861 break;
2862 if (key.offset >= new->file_pos + new->len)
2863 break;
2864
2865 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2866
2867 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2868 if (key.offset + num_bytes < new->file_pos)
2869 goto next;
2870
2871 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2872 if (!disk_bytenr)
2873 goto next;
2874
2875 extent_offset = btrfs_file_extent_offset(l, extent);
2876
2877 old = kmalloc(sizeof(*old), GFP_NOFS);
2878 if (!old)
2879 goto out_free_path;
2880
2881 offset = max(new->file_pos, key.offset);
2882 end = min(new->file_pos + new->len, key.offset + num_bytes);
2883
2884 old->bytenr = disk_bytenr;
2885 old->extent_offset = extent_offset;
2886 old->offset = offset - key.offset;
2887 old->len = end - offset;
2888 old->new = new;
2889 old->count = 0;
2890 list_add_tail(&old->list, &new->head);
2891 next:
2892 path->slots[0]++;
2893 cond_resched();
2894 }
2895
2896 btrfs_free_path(path);
2897 atomic_inc(&fs_info->defrag_running);
2898
2899 return new;
2900
2901 out_free_path:
2902 btrfs_free_path(path);
2903 out_kfree:
2904 free_sa_defrag_extent(new);
2905 return NULL;
2906 }
2907
2908 static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info,
2909 u64 start, u64 len)
2910 {
2911 struct btrfs_block_group_cache *cache;
2912
2913 cache = btrfs_lookup_block_group(fs_info, start);
2914 ASSERT(cache);
2915
2916 spin_lock(&cache->lock);
2917 cache->delalloc_bytes -= len;
2918 spin_unlock(&cache->lock);
2919
2920 btrfs_put_block_group(cache);
2921 }
2922
2923 /* as ordered data IO finishes, this gets called so we can finish
2924 * an ordered extent if the range of bytes in the file it covers are
2925 * fully written.
2926 */
2927 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2928 {
2929 struct inode *inode = ordered_extent->inode;
2930 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2931 struct btrfs_root *root = BTRFS_I(inode)->root;
2932 struct btrfs_trans_handle *trans = NULL;
2933 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2934 struct extent_state *cached_state = NULL;
2935 struct new_sa_defrag_extent *new = NULL;
2936 int compress_type = 0;
2937 int ret = 0;
2938 u64 logical_len = ordered_extent->len;
2939 bool nolock;
2940 bool truncated = false;
2941 bool range_locked = false;
2942 bool clear_new_delalloc_bytes = false;
2943
2944 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2945 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) &&
2946 !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags))
2947 clear_new_delalloc_bytes = true;
2948
2949 nolock = btrfs_is_free_space_inode(BTRFS_I(inode));
2950
2951 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2952 ret = -EIO;
2953 goto out;
2954 }
2955
2956 btrfs_free_io_failure_record(BTRFS_I(inode),
2957 ordered_extent->file_offset,
2958 ordered_extent->file_offset +
2959 ordered_extent->len - 1);
2960
2961 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) {
2962 truncated = true;
2963 logical_len = ordered_extent->truncated_len;
2964 /* Truncated the entire extent, don't bother adding */
2965 if (!logical_len)
2966 goto out;
2967 }
2968
2969 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2970 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2971
2972 /*
2973 * For mwrite(mmap + memset to write) case, we still reserve
2974 * space for NOCOW range.
2975 * As NOCOW won't cause a new delayed ref, just free the space
2976 */
2977 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset,
2978 ordered_extent->len);
2979 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2980 if (nolock)
2981 trans = btrfs_join_transaction_nolock(root);
2982 else
2983 trans = btrfs_join_transaction(root);
2984 if (IS_ERR(trans)) {
2985 ret = PTR_ERR(trans);
2986 trans = NULL;
2987 goto out;
2988 }
2989 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
2990 ret = btrfs_update_inode_fallback(trans, root, inode);
2991 if (ret) /* -ENOMEM or corruption */
2992 btrfs_abort_transaction(trans, ret);
2993 goto out;
2994 }
2995
2996 range_locked = true;
2997 lock_extent_bits(io_tree, ordered_extent->file_offset,
2998 ordered_extent->file_offset + ordered_extent->len - 1,
2999 &cached_state);
3000
3001 ret = test_range_bit(io_tree, ordered_extent->file_offset,
3002 ordered_extent->file_offset + ordered_extent->len - 1,
3003 EXTENT_DEFRAG, 0, cached_state);
3004 if (ret) {
3005 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
3006 if (0 && last_snapshot >= BTRFS_I(inode)->generation)
3007 /* the inode is shared */
3008 new = record_old_file_extents(inode, ordered_extent);
3009
3010 clear_extent_bit(io_tree, ordered_extent->file_offset,
3011 ordered_extent->file_offset + ordered_extent->len - 1,
3012 EXTENT_DEFRAG, 0, 0, &cached_state);
3013 }
3014
3015 if (nolock)
3016 trans = btrfs_join_transaction_nolock(root);
3017 else
3018 trans = btrfs_join_transaction(root);
3019 if (IS_ERR(trans)) {
3020 ret = PTR_ERR(trans);
3021 trans = NULL;
3022 goto out;
3023 }
3024
3025 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
3026
3027 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
3028 compress_type = ordered_extent->compress_type;
3029 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
3030 BUG_ON(compress_type);
3031 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset,
3032 ordered_extent->len);
3033 ret = btrfs_mark_extent_written(trans, BTRFS_I(inode),
3034 ordered_extent->file_offset,
3035 ordered_extent->file_offset +
3036 logical_len);
3037 } else {
3038 BUG_ON(root == fs_info->tree_root);
3039 ret = insert_reserved_file_extent(trans, inode,
3040 ordered_extent->file_offset,
3041 ordered_extent->start,
3042 ordered_extent->disk_len,
3043 logical_len, logical_len,
3044 compress_type, 0, 0,
3045 BTRFS_FILE_EXTENT_REG);
3046 if (!ret)
3047 btrfs_release_delalloc_bytes(fs_info,
3048 ordered_extent->start,
3049 ordered_extent->disk_len);
3050 }
3051 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
3052 ordered_extent->file_offset, ordered_extent->len,
3053 trans->transid);
3054 if (ret < 0) {
3055 btrfs_abort_transaction(trans, ret);
3056 goto out;
3057 }
3058
3059 ret = add_pending_csums(trans, inode, &ordered_extent->list);
3060 if (ret) {
3061 btrfs_abort_transaction(trans, ret);
3062 goto out;
3063 }
3064
3065 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
3066 ret = btrfs_update_inode_fallback(trans, root, inode);
3067 if (ret) { /* -ENOMEM or corruption */
3068 btrfs_abort_transaction(trans, ret);
3069 goto out;
3070 }
3071 ret = 0;
3072 out:
3073 if (range_locked || clear_new_delalloc_bytes) {
3074 unsigned int clear_bits = 0;
3075
3076 if (range_locked)
3077 clear_bits |= EXTENT_LOCKED;
3078 if (clear_new_delalloc_bytes)
3079 clear_bits |= EXTENT_DELALLOC_NEW;
3080 clear_extent_bit(&BTRFS_I(inode)->io_tree,
3081 ordered_extent->file_offset,
3082 ordered_extent->file_offset +
3083 ordered_extent->len - 1,
3084 clear_bits,
3085 (clear_bits & EXTENT_LOCKED) ? 1 : 0,
3086 0, &cached_state);
3087 }
3088
3089 if (trans)
3090 btrfs_end_transaction(trans);
3091
3092 if (ret || truncated) {
3093 u64 start, end;
3094
3095 if (truncated)
3096 start = ordered_extent->file_offset + logical_len;
3097 else
3098 start = ordered_extent->file_offset;
3099 end = ordered_extent->file_offset + ordered_extent->len - 1;
3100 clear_extent_uptodate(io_tree, start, end, NULL);
3101
3102 /* Drop the cache for the part of the extent we didn't write. */
3103 btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0);
3104
3105 /*
3106 * If the ordered extent had an IOERR or something else went
3107 * wrong we need to return the space for this ordered extent
3108 * back to the allocator. We only free the extent in the
3109 * truncated case if we didn't write out the extent at all.
3110 */
3111 if ((ret || !logical_len) &&
3112 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
3113 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
3114 btrfs_free_reserved_extent(fs_info,
3115 ordered_extent->start,
3116 ordered_extent->disk_len, 1);
3117 }
3118
3119
3120 /*
3121 * This needs to be done to make sure anybody waiting knows we are done
3122 * updating everything for this ordered extent.
3123 */
3124 btrfs_remove_ordered_extent(inode, ordered_extent);
3125
3126 /* for snapshot-aware defrag */
3127 if (new) {
3128 if (ret) {
3129 free_sa_defrag_extent(new);
3130 atomic_dec(&fs_info->defrag_running);
3131 } else {
3132 relink_file_extents(new);
3133 }
3134 }
3135
3136 /* once for us */
3137 btrfs_put_ordered_extent(ordered_extent);
3138 /* once for the tree */
3139 btrfs_put_ordered_extent(ordered_extent);
3140
3141 /* Try to release some metadata so we don't get an OOM but don't wait */
3142 btrfs_btree_balance_dirty_nodelay(fs_info);
3143
3144 return ret;
3145 }
3146
3147 static void finish_ordered_fn(struct btrfs_work *work)
3148 {
3149 struct btrfs_ordered_extent *ordered_extent;
3150 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
3151 btrfs_finish_ordered_io(ordered_extent);
3152 }
3153
3154 static void btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
3155 struct extent_state *state, int uptodate)
3156 {
3157 struct inode *inode = page->mapping->host;
3158 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3159 struct btrfs_ordered_extent *ordered_extent = NULL;
3160 struct btrfs_workqueue *wq;
3161 btrfs_work_func_t func;
3162
3163 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
3164
3165 ClearPagePrivate2(page);
3166 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
3167 end - start + 1, uptodate))
3168 return;
3169
3170 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
3171 wq = fs_info->endio_freespace_worker;
3172 func = btrfs_freespace_write_helper;
3173 } else {
3174 wq = fs_info->endio_write_workers;
3175 func = btrfs_endio_write_helper;
3176 }
3177
3178 btrfs_init_work(&ordered_extent->work, func, finish_ordered_fn, NULL,
3179 NULL);
3180 btrfs_queue_work(wq, &ordered_extent->work);
3181 }
3182
3183 static int __readpage_endio_check(struct inode *inode,
3184 struct btrfs_io_bio *io_bio,
3185 int icsum, struct page *page,
3186 int pgoff, u64 start, size_t len)
3187 {
3188 char *kaddr;
3189 u32 csum_expected;
3190 u32 csum = ~(u32)0;
3191
3192 csum_expected = *(((u32 *)io_bio->csum) + icsum);
3193
3194 kaddr = kmap_atomic(page);
3195 csum = btrfs_csum_data(kaddr + pgoff, csum, len);
3196 btrfs_csum_final(csum, (u8 *)&csum);
3197 if (csum != csum_expected)
3198 goto zeroit;
3199
3200 kunmap_atomic(kaddr);
3201 return 0;
3202 zeroit:
3203 btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected,
3204 io_bio->mirror_num);
3205 memset(kaddr + pgoff, 1, len);
3206 flush_dcache_page(page);
3207 kunmap_atomic(kaddr);
3208 return -EIO;
3209 }
3210
3211 /*
3212 * when reads are done, we need to check csums to verify the data is correct
3213 * if there's a match, we allow the bio to finish. If not, the code in
3214 * extent_io.c will try to find good copies for us.
3215 */
3216 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
3217 u64 phy_offset, struct page *page,
3218 u64 start, u64 end, int mirror)
3219 {
3220 size_t offset = start - page_offset(page);
3221 struct inode *inode = page->mapping->host;
3222 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3223 struct btrfs_root *root = BTRFS_I(inode)->root;
3224
3225 if (PageChecked(page)) {
3226 ClearPageChecked(page);
3227 return 0;
3228 }
3229
3230 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
3231 return 0;
3232
3233 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
3234 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
3235 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM);
3236 return 0;
3237 }
3238
3239 phy_offset >>= inode->i_sb->s_blocksize_bits;
3240 return __readpage_endio_check(inode, io_bio, phy_offset, page, offset,
3241 start, (size_t)(end - start + 1));
3242 }
3243
3244 /*
3245 * btrfs_add_delayed_iput - perform a delayed iput on @inode
3246 *
3247 * @inode: The inode we want to perform iput on
3248 *
3249 * This function uses the generic vfs_inode::i_count to track whether we should
3250 * just decrement it (in case it's > 1) or if this is the last iput then link
3251 * the inode to the delayed iput machinery. Delayed iputs are processed at
3252 * transaction commit time/superblock commit/cleaner kthread.
3253 */
3254 void btrfs_add_delayed_iput(struct inode *inode)
3255 {
3256 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3257 struct btrfs_inode *binode = BTRFS_I(inode);
3258
3259 if (atomic_add_unless(&inode->i_count, -1, 1))
3260 return;
3261
3262 spin_lock(&fs_info->delayed_iput_lock);
3263 ASSERT(list_empty(&binode->delayed_iput));
3264 list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs);
3265 spin_unlock(&fs_info->delayed_iput_lock);
3266 }
3267
3268 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
3269 {
3270
3271 spin_lock(&fs_info->delayed_iput_lock);
3272 while (!list_empty(&fs_info->delayed_iputs)) {
3273 struct btrfs_inode *inode;
3274
3275 inode = list_first_entry(&fs_info->delayed_iputs,
3276 struct btrfs_inode, delayed_iput);
3277 list_del_init(&inode->delayed_iput);
3278 spin_unlock(&fs_info->delayed_iput_lock);
3279 iput(&inode->vfs_inode);
3280 spin_lock(&fs_info->delayed_iput_lock);
3281 }
3282 spin_unlock(&fs_info->delayed_iput_lock);
3283 }
3284
3285 /*
3286 * This creates an orphan entry for the given inode in case something goes wrong
3287 * in the middle of an unlink.
3288 */
3289 int btrfs_orphan_add(struct btrfs_trans_handle *trans,
3290 struct btrfs_inode *inode)
3291 {
3292 int ret;
3293
3294 ret = btrfs_insert_orphan_item(trans, inode->root, btrfs_ino(inode));
3295 if (ret && ret != -EEXIST) {
3296 btrfs_abort_transaction(trans, ret);
3297 return ret;
3298 }
3299
3300 return 0;
3301 }
3302
3303 /*
3304 * We have done the delete so we can go ahead and remove the orphan item for
3305 * this particular inode.
3306 */
3307 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
3308 struct btrfs_inode *inode)
3309 {
3310 return btrfs_del_orphan_item(trans, inode->root, btrfs_ino(inode));
3311 }
3312
3313 /*
3314 * this cleans up any orphans that may be left on the list from the last use
3315 * of this root.
3316 */
3317 int btrfs_orphan_cleanup(struct btrfs_root *root)
3318 {
3319 struct btrfs_fs_info *fs_info = root->fs_info;
3320 struct btrfs_path *path;
3321 struct extent_buffer *leaf;
3322 struct btrfs_key key, found_key;
3323 struct btrfs_trans_handle *trans;
3324 struct inode *inode;
3325 u64 last_objectid = 0;
3326 int ret = 0, nr_unlink = 0;
3327
3328 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3329 return 0;
3330
3331 path = btrfs_alloc_path();
3332 if (!path) {
3333 ret = -ENOMEM;
3334 goto out;
3335 }
3336 path->reada = READA_BACK;
3337
3338 key.objectid = BTRFS_ORPHAN_OBJECTID;
3339 key.type = BTRFS_ORPHAN_ITEM_KEY;
3340 key.offset = (u64)-1;
3341
3342 while (1) {
3343 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3344 if (ret < 0)
3345 goto out;
3346
3347 /*
3348 * if ret == 0 means we found what we were searching for, which
3349 * is weird, but possible, so only screw with path if we didn't
3350 * find the key and see if we have stuff that matches
3351 */
3352 if (ret > 0) {
3353 ret = 0;
3354 if (path->slots[0] == 0)
3355 break;
3356 path->slots[0]--;
3357 }
3358
3359 /* pull out the item */
3360 leaf = path->nodes[0];
3361 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3362
3363 /* make sure the item matches what we want */
3364 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3365 break;
3366 if (found_key.type != BTRFS_ORPHAN_ITEM_KEY)
3367 break;
3368
3369 /* release the path since we're done with it */
3370 btrfs_release_path(path);
3371
3372 /*
3373 * this is where we are basically btrfs_lookup, without the
3374 * crossing root thing. we store the inode number in the
3375 * offset of the orphan item.
3376 */
3377
3378 if (found_key.offset == last_objectid) {
3379 btrfs_err(fs_info,
3380 "Error removing orphan entry, stopping orphan cleanup");
3381 ret = -EINVAL;
3382 goto out;
3383 }
3384
3385 last_objectid = found_key.offset;
3386
3387 found_key.objectid = found_key.offset;
3388 found_key.type = BTRFS_INODE_ITEM_KEY;
3389 found_key.offset = 0;
3390 inode = btrfs_iget(fs_info->sb, &found_key, root, NULL);
3391 ret = PTR_ERR_OR_ZERO(inode);
3392 if (ret && ret != -ENOENT)
3393 goto out;
3394
3395 if (ret == -ENOENT && root == fs_info->tree_root) {
3396 struct btrfs_root *dead_root;
3397 struct btrfs_fs_info *fs_info = root->fs_info;
3398 int is_dead_root = 0;
3399
3400 /*
3401 * this is an orphan in the tree root. Currently these
3402 * could come from 2 sources:
3403 * a) a snapshot deletion in progress
3404 * b) a free space cache inode
3405 * We need to distinguish those two, as the snapshot
3406 * orphan must not get deleted.
3407 * find_dead_roots already ran before us, so if this
3408 * is a snapshot deletion, we should find the root
3409 * in the dead_roots list
3410 */
3411 spin_lock(&fs_info->trans_lock);
3412 list_for_each_entry(dead_root, &fs_info->dead_roots,
3413 root_list) {
3414 if (dead_root->root_key.objectid ==
3415 found_key.objectid) {
3416 is_dead_root = 1;
3417 break;
3418 }
3419 }
3420 spin_unlock(&fs_info->trans_lock);
3421 if (is_dead_root) {
3422 /* prevent this orphan from being found again */
3423 key.offset = found_key.objectid - 1;
3424 continue;
3425 }
3426
3427 }
3428
3429 /*
3430 * If we have an inode with links, there are a couple of
3431 * possibilities. Old kernels (before v3.12) used to create an
3432 * orphan item for truncate indicating that there were possibly
3433 * extent items past i_size that needed to be deleted. In v3.12,
3434 * truncate was changed to update i_size in sync with the extent
3435 * items, but the (useless) orphan item was still created. Since
3436 * v4.18, we don't create the orphan item for truncate at all.
3437 *
3438 * So, this item could mean that we need to do a truncate, but
3439 * only if this filesystem was last used on a pre-v3.12 kernel
3440 * and was not cleanly unmounted. The odds of that are quite
3441 * slim, and it's a pain to do the truncate now, so just delete
3442 * the orphan item.
3443 *
3444 * It's also possible that this orphan item was supposed to be
3445 * deleted but wasn't. The inode number may have been reused,
3446 * but either way, we can delete the orphan item.
3447 */
3448 if (ret == -ENOENT || inode->i_nlink) {
3449 if (!ret)
3450 iput(inode);
3451 trans = btrfs_start_transaction(root, 1);
3452 if (IS_ERR(trans)) {
3453 ret = PTR_ERR(trans);
3454 goto out;
3455 }
3456 btrfs_debug(fs_info, "auto deleting %Lu",
3457 found_key.objectid);
3458 ret = btrfs_del_orphan_item(trans, root,
3459 found_key.objectid);
3460 btrfs_end_transaction(trans);
3461 if (ret)
3462 goto out;
3463 continue;
3464 }
3465
3466 nr_unlink++;
3467
3468 /* this will do delete_inode and everything for us */
3469 iput(inode);
3470 }
3471 /* release the path since we're done with it */
3472 btrfs_release_path(path);
3473
3474 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3475
3476 if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) {
3477 trans = btrfs_join_transaction(root);
3478 if (!IS_ERR(trans))
3479 btrfs_end_transaction(trans);
3480 }
3481
3482 if (nr_unlink)
3483 btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink);
3484
3485 out:
3486 if (ret)
3487 btrfs_err(fs_info, "could not do orphan cleanup %d", ret);
3488 btrfs_free_path(path);
3489 return ret;
3490 }
3491
3492 /*
3493 * very simple check to peek ahead in the leaf looking for xattrs. If we
3494 * don't find any xattrs, we know there can't be any acls.
3495 *
3496 * slot is the slot the inode is in, objectid is the objectid of the inode
3497 */
3498 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3499 int slot, u64 objectid,
3500 int *first_xattr_slot)
3501 {
3502 u32 nritems = btrfs_header_nritems(leaf);
3503 struct btrfs_key found_key;
3504 static u64 xattr_access = 0;
3505 static u64 xattr_default = 0;
3506 int scanned = 0;
3507
3508 if (!xattr_access) {
3509 xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS,
3510 strlen(XATTR_NAME_POSIX_ACL_ACCESS));
3511 xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT,
3512 strlen(XATTR_NAME_POSIX_ACL_DEFAULT));
3513 }
3514
3515 slot++;
3516 *first_xattr_slot = -1;
3517 while (slot < nritems) {
3518 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3519
3520 /* we found a different objectid, there must not be acls */
3521 if (found_key.objectid != objectid)
3522 return 0;
3523
3524 /* we found an xattr, assume we've got an acl */
3525 if (found_key.type == BTRFS_XATTR_ITEM_KEY) {
3526 if (*first_xattr_slot == -1)
3527 *first_xattr_slot = slot;
3528 if (found_key.offset == xattr_access ||
3529 found_key.offset == xattr_default)
3530 return 1;
3531 }
3532
3533 /*
3534 * we found a key greater than an xattr key, there can't
3535 * be any acls later on
3536 */
3537 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3538 return 0;
3539
3540 slot++;
3541 scanned++;
3542
3543 /*
3544 * it goes inode, inode backrefs, xattrs, extents,
3545 * so if there are a ton of hard links to an inode there can
3546 * be a lot of backrefs. Don't waste time searching too hard,
3547 * this is just an optimization
3548 */
3549 if (scanned >= 8)
3550 break;
3551 }
3552 /* we hit the end of the leaf before we found an xattr or
3553 * something larger than an xattr. We have to assume the inode
3554 * has acls
3555 */
3556 if (*first_xattr_slot == -1)
3557 *first_xattr_slot = slot;
3558 return 1;
3559 }
3560
3561 /*
3562 * read an inode from the btree into the in-memory inode
3563 */
3564 static int btrfs_read_locked_inode(struct inode *inode)
3565 {
3566 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3567 struct btrfs_path *path;
3568 struct extent_buffer *leaf;
3569 struct btrfs_inode_item *inode_item;
3570 struct btrfs_root *root = BTRFS_I(inode)->root;
3571 struct btrfs_key location;
3572 unsigned long ptr;
3573 int maybe_acls;
3574 u32 rdev;
3575 int ret;
3576 bool filled = false;
3577 int first_xattr_slot;
3578
3579 ret = btrfs_fill_inode(inode, &rdev);
3580 if (!ret)
3581 filled = true;
3582
3583 path = btrfs_alloc_path();
3584 if (!path)
3585 return -ENOMEM;
3586
3587 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3588
3589 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3590 if (ret) {
3591 btrfs_free_path(path);
3592 return ret;
3593 }
3594
3595 leaf = path->nodes[0];
3596
3597 if (filled)
3598 goto cache_index;
3599
3600 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3601 struct btrfs_inode_item);
3602 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3603 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3604 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3605 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3606 btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item));
3607
3608 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime);
3609 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime);
3610
3611 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime);
3612 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime);
3613
3614 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime);
3615 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime);
3616
3617 BTRFS_I(inode)->i_otime.tv_sec =
3618 btrfs_timespec_sec(leaf, &inode_item->otime);
3619 BTRFS_I(inode)->i_otime.tv_nsec =
3620 btrfs_timespec_nsec(leaf, &inode_item->otime);
3621
3622 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3623 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3624 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3625
3626 inode_set_iversion_queried(inode,
3627 btrfs_inode_sequence(leaf, inode_item));
3628 inode->i_generation = BTRFS_I(inode)->generation;
3629 inode->i_rdev = 0;
3630 rdev = btrfs_inode_rdev(leaf, inode_item);
3631
3632 BTRFS_I(inode)->index_cnt = (u64)-1;
3633 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3634
3635 cache_index:
3636 /*
3637 * If we were modified in the current generation and evicted from memory
3638 * and then re-read we need to do a full sync since we don't have any
3639 * idea about which extents were modified before we were evicted from
3640 * cache.
3641 *
3642 * This is required for both inode re-read from disk and delayed inode
3643 * in delayed_nodes_tree.
3644 */
3645 if (BTRFS_I(inode)->last_trans == fs_info->generation)
3646 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3647 &BTRFS_I(inode)->runtime_flags);
3648
3649 /*
3650 * We don't persist the id of the transaction where an unlink operation
3651 * against the inode was last made. So here we assume the inode might
3652 * have been evicted, and therefore the exact value of last_unlink_trans
3653 * lost, and set it to last_trans to avoid metadata inconsistencies
3654 * between the inode and its parent if the inode is fsync'ed and the log
3655 * replayed. For example, in the scenario:
3656 *
3657 * touch mydir/foo
3658 * ln mydir/foo mydir/bar
3659 * sync
3660 * unlink mydir/bar
3661 * echo 2 > /proc/sys/vm/drop_caches # evicts inode
3662 * xfs_io -c fsync mydir/foo
3663 * <power failure>
3664 * mount fs, triggers fsync log replay
3665 *
3666 * We must make sure that when we fsync our inode foo we also log its
3667 * parent inode, otherwise after log replay the parent still has the
3668 * dentry with the "bar" name but our inode foo has a link count of 1
3669 * and doesn't have an inode ref with the name "bar" anymore.
3670 *
3671 * Setting last_unlink_trans to last_trans is a pessimistic approach,
3672 * but it guarantees correctness at the expense of occasional full
3673 * transaction commits on fsync if our inode is a directory, or if our
3674 * inode is not a directory, logging its parent unnecessarily.
3675 */
3676 BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans;
3677
3678 path->slots[0]++;
3679 if (inode->i_nlink != 1 ||
3680 path->slots[0] >= btrfs_header_nritems(leaf))
3681 goto cache_acl;
3682
3683 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]);
3684 if (location.objectid != btrfs_ino(BTRFS_I(inode)))
3685 goto cache_acl;
3686
3687 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
3688 if (location.type == BTRFS_INODE_REF_KEY) {
3689 struct btrfs_inode_ref *ref;
3690
3691 ref = (struct btrfs_inode_ref *)ptr;
3692 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref);
3693 } else if (location.type == BTRFS_INODE_EXTREF_KEY) {
3694 struct btrfs_inode_extref *extref;
3695
3696 extref = (struct btrfs_inode_extref *)ptr;
3697 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf,
3698 extref);
3699 }
3700 cache_acl:
3701 /*
3702 * try to precache a NULL acl entry for files that don't have
3703 * any xattrs or acls
3704 */
3705 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3706 btrfs_ino(BTRFS_I(inode)), &first_xattr_slot);
3707 if (first_xattr_slot != -1) {
3708 path->slots[0] = first_xattr_slot;
3709 ret = btrfs_load_inode_props(inode, path);
3710 if (ret)
3711 btrfs_err(fs_info,
3712 "error loading props for ino %llu (root %llu): %d",
3713 btrfs_ino(BTRFS_I(inode)),
3714 root->root_key.objectid, ret);
3715 }
3716 btrfs_free_path(path);
3717
3718 if (!maybe_acls)
3719 cache_no_acl(inode);
3720
3721 switch (inode->i_mode & S_IFMT) {
3722 case S_IFREG:
3723 inode->i_mapping->a_ops = &btrfs_aops;
3724 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3725 inode->i_fop = &btrfs_file_operations;
3726 inode->i_op = &btrfs_file_inode_operations;
3727 break;
3728 case S_IFDIR:
3729 inode->i_fop = &btrfs_dir_file_operations;
3730 inode->i_op = &btrfs_dir_inode_operations;
3731 break;
3732 case S_IFLNK:
3733 inode->i_op = &btrfs_symlink_inode_operations;
3734 inode_nohighmem(inode);
3735 inode->i_mapping->a_ops = &btrfs_aops;
3736 break;
3737 default:
3738 inode->i_op = &btrfs_special_inode_operations;
3739 init_special_inode(inode, inode->i_mode, rdev);
3740 break;
3741 }
3742
3743 btrfs_sync_inode_flags_to_i_flags(inode);
3744 return 0;
3745 }
3746
3747 /*
3748 * given a leaf and an inode, copy the inode fields into the leaf
3749 */
3750 static void fill_inode_item(struct btrfs_trans_handle *trans,
3751 struct extent_buffer *leaf,
3752 struct btrfs_inode_item *item,
3753 struct inode *inode)
3754 {
3755 struct btrfs_map_token token;
3756
3757 btrfs_init_map_token(&token);
3758
3759 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3760 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3761 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3762 &token);
3763 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3764 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
3765
3766 btrfs_set_token_timespec_sec(leaf, &item->atime,
3767 inode->i_atime.tv_sec, &token);
3768 btrfs_set_token_timespec_nsec(leaf, &item->atime,
3769 inode->i_atime.tv_nsec, &token);
3770
3771 btrfs_set_token_timespec_sec(leaf, &item->mtime,
3772 inode->i_mtime.tv_sec, &token);
3773 btrfs_set_token_timespec_nsec(leaf, &item->mtime,
3774 inode->i_mtime.tv_nsec, &token);
3775
3776 btrfs_set_token_timespec_sec(leaf, &item->ctime,
3777 inode->i_ctime.tv_sec, &token);
3778 btrfs_set_token_timespec_nsec(leaf, &item->ctime,
3779 inode->i_ctime.tv_nsec, &token);
3780
3781 btrfs_set_token_timespec_sec(leaf, &item->otime,
3782 BTRFS_I(inode)->i_otime.tv_sec, &token);
3783 btrfs_set_token_timespec_nsec(leaf, &item->otime,
3784 BTRFS_I(inode)->i_otime.tv_nsec, &token);
3785
3786 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3787 &token);
3788 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3789 &token);
3790 btrfs_set_token_inode_sequence(leaf, item, inode_peek_iversion(inode),
3791 &token);
3792 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3793 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3794 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3795 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
3796 }
3797
3798 /*
3799 * copy everything in the in-memory inode into the btree.
3800 */
3801 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3802 struct btrfs_root *root, struct inode *inode)
3803 {
3804 struct btrfs_inode_item *inode_item;
3805 struct btrfs_path *path;
3806 struct extent_buffer *leaf;
3807 int ret;
3808
3809 path = btrfs_alloc_path();
3810 if (!path)
3811 return -ENOMEM;
3812
3813 path->leave_spinning = 1;
3814 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3815 1);
3816 if (ret) {
3817 if (ret > 0)
3818 ret = -ENOENT;
3819 goto failed;
3820 }
3821
3822 leaf = path->nodes[0];
3823 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3824 struct btrfs_inode_item);
3825
3826 fill_inode_item(trans, leaf, inode_item, inode);
3827 btrfs_mark_buffer_dirty(leaf);
3828 btrfs_set_inode_last_trans(trans, inode);
3829 ret = 0;
3830 failed:
3831 btrfs_free_path(path);
3832 return ret;
3833 }
3834
3835 /*
3836 * copy everything in the in-memory inode into the btree.
3837 */
3838 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3839 struct btrfs_root *root, struct inode *inode)
3840 {
3841 struct btrfs_fs_info *fs_info = root->fs_info;
3842 int ret;
3843
3844 /*
3845 * If the inode is a free space inode, we can deadlock during commit
3846 * if we put it into the delayed code.
3847 *
3848 * The data relocation inode should also be directly updated
3849 * without delay
3850 */
3851 if (!btrfs_is_free_space_inode(BTRFS_I(inode))
3852 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
3853 && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) {
3854 btrfs_update_root_times(trans, root);
3855
3856 ret = btrfs_delayed_update_inode(trans, root, inode);
3857 if (!ret)
3858 btrfs_set_inode_last_trans(trans, inode);
3859 return ret;
3860 }
3861
3862 return btrfs_update_inode_item(trans, root, inode);
3863 }
3864
3865 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3866 struct btrfs_root *root,
3867 struct inode *inode)
3868 {
3869 int ret;
3870
3871 ret = btrfs_update_inode(trans, root, inode);
3872 if (ret == -ENOSPC)
3873 return btrfs_update_inode_item(trans, root, inode);
3874 return ret;
3875 }
3876
3877 /*
3878 * unlink helper that gets used here in inode.c and in the tree logging
3879 * recovery code. It remove a link in a directory with a given name, and
3880 * also drops the back refs in the inode to the directory
3881 */
3882 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3883 struct btrfs_root *root,
3884 struct btrfs_inode *dir,
3885 struct btrfs_inode *inode,
3886 const char *name, int name_len)
3887 {
3888 struct btrfs_fs_info *fs_info = root->fs_info;
3889 struct btrfs_path *path;
3890 int ret = 0;
3891 struct extent_buffer *leaf;
3892 struct btrfs_dir_item *di;
3893 struct btrfs_key key;
3894 u64 index;
3895 u64 ino = btrfs_ino(inode);
3896 u64 dir_ino = btrfs_ino(dir);
3897
3898 path = btrfs_alloc_path();
3899 if (!path) {
3900 ret = -ENOMEM;
3901 goto out;
3902 }
3903
3904 path->leave_spinning = 1;
3905 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3906 name, name_len, -1);
3907 if (IS_ERR_OR_NULL(di)) {
3908 ret = di ? PTR_ERR(di) : -ENOENT;
3909 goto err;
3910 }
3911 leaf = path->nodes[0];
3912 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3913 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3914 if (ret)
3915 goto err;
3916 btrfs_release_path(path);
3917
3918 /*
3919 * If we don't have dir index, we have to get it by looking up
3920 * the inode ref, since we get the inode ref, remove it directly,
3921 * it is unnecessary to do delayed deletion.
3922 *
3923 * But if we have dir index, needn't search inode ref to get it.
3924 * Since the inode ref is close to the inode item, it is better
3925 * that we delay to delete it, and just do this deletion when
3926 * we update the inode item.
3927 */
3928 if (inode->dir_index) {
3929 ret = btrfs_delayed_delete_inode_ref(inode);
3930 if (!ret) {
3931 index = inode->dir_index;
3932 goto skip_backref;
3933 }
3934 }
3935
3936 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3937 dir_ino, &index);
3938 if (ret) {
3939 btrfs_info(fs_info,
3940 "failed to delete reference to %.*s, inode %llu parent %llu",
3941 name_len, name, ino, dir_ino);
3942 btrfs_abort_transaction(trans, ret);
3943 goto err;
3944 }
3945 skip_backref:
3946 ret = btrfs_delete_delayed_dir_index(trans, dir, index);
3947 if (ret) {
3948 btrfs_abort_transaction(trans, ret);
3949 goto err;
3950 }
3951
3952 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, inode,
3953 dir_ino);
3954 if (ret != 0 && ret != -ENOENT) {
3955 btrfs_abort_transaction(trans, ret);
3956 goto err;
3957 }
3958
3959 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, dir,
3960 index);
3961 if (ret == -ENOENT)
3962 ret = 0;
3963 else if (ret)
3964 btrfs_abort_transaction(trans, ret);
3965 err:
3966 btrfs_free_path(path);
3967 if (ret)
3968 goto out;
3969
3970 btrfs_i_size_write(dir, dir->vfs_inode.i_size - name_len * 2);
3971 inode_inc_iversion(&inode->vfs_inode);
3972 inode_inc_iversion(&dir->vfs_inode);
3973 inode->vfs_inode.i_ctime = dir->vfs_inode.i_mtime =
3974 dir->vfs_inode.i_ctime = current_time(&inode->vfs_inode);
3975 ret = btrfs_update_inode(trans, root, &dir->vfs_inode);
3976 out:
3977 return ret;
3978 }
3979
3980 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3981 struct btrfs_root *root,
3982 struct btrfs_inode *dir, struct btrfs_inode *inode,
3983 const char *name, int name_len)
3984 {
3985 int ret;
3986 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3987 if (!ret) {
3988 drop_nlink(&inode->vfs_inode);
3989 ret = btrfs_update_inode(trans, root, &inode->vfs_inode);
3990 }
3991 return ret;
3992 }
3993
3994 /*
3995 * helper to start transaction for unlink and rmdir.
3996 *
3997 * unlink and rmdir are special in btrfs, they do not always free space, so
3998 * if we cannot make our reservations the normal way try and see if there is
3999 * plenty of slack room in the global reserve to migrate, otherwise we cannot
4000 * allow the unlink to occur.
4001 */
4002 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir)
4003 {
4004 struct btrfs_root *root = BTRFS_I(dir)->root;
4005
4006 /*
4007 * 1 for the possible orphan item
4008 * 1 for the dir item
4009 * 1 for the dir index
4010 * 1 for the inode ref
4011 * 1 for the inode
4012 */
4013 return btrfs_start_transaction_fallback_global_rsv(root, 5, 5);
4014 }
4015
4016 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
4017 {
4018 struct btrfs_root *root = BTRFS_I(dir)->root;
4019 struct btrfs_trans_handle *trans;
4020 struct inode *inode = d_inode(dentry);
4021 int ret;
4022
4023 trans = __unlink_start_trans(dir);
4024 if (IS_ERR(trans))
4025 return PTR_ERR(trans);
4026
4027 btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)),
4028 0);
4029
4030 ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir),
4031 BTRFS_I(d_inode(dentry)), dentry->d_name.name,
4032 dentry->d_name.len);
4033 if (ret)
4034 goto out;
4035
4036 if (inode->i_nlink == 0) {
4037 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
4038 if (ret)
4039 goto out;
4040 }
4041
4042 out:
4043 btrfs_end_transaction(trans);
4044 btrfs_btree_balance_dirty(root->fs_info);
4045 return ret;
4046 }
4047
4048 static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
4049 struct inode *dir, u64 objectid,
4050 const char *name, int name_len)
4051 {
4052 struct btrfs_root *root = BTRFS_I(dir)->root;
4053 struct btrfs_path *path;
4054 struct extent_buffer *leaf;
4055 struct btrfs_dir_item *di;
4056 struct btrfs_key key;
4057 u64 index;
4058 int ret;
4059 u64 dir_ino = btrfs_ino(BTRFS_I(dir));
4060
4061 path = btrfs_alloc_path();
4062 if (!path)
4063 return -ENOMEM;
4064
4065 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
4066 name, name_len, -1);
4067 if (IS_ERR_OR_NULL(di)) {
4068 ret = di ? PTR_ERR(di) : -ENOENT;
4069 goto out;
4070 }
4071
4072 leaf = path->nodes[0];
4073 btrfs_dir_item_key_to_cpu(leaf, di, &key);
4074 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
4075 ret = btrfs_delete_one_dir_name(trans, root, path, di);
4076 if (ret) {
4077 btrfs_abort_transaction(trans, ret);
4078 goto out;
4079 }
4080 btrfs_release_path(path);
4081
4082 ret = btrfs_del_root_ref(trans, objectid, root->root_key.objectid,
4083 dir_ino, &index, name, name_len);
4084 if (ret < 0) {
4085 if (ret != -ENOENT) {
4086 btrfs_abort_transaction(trans, ret);
4087 goto out;
4088 }
4089 di = btrfs_search_dir_index_item(root, path, dir_ino,
4090 name, name_len);
4091 if (IS_ERR_OR_NULL(di)) {
4092 if (!di)
4093 ret = -ENOENT;
4094 else
4095 ret = PTR_ERR(di);
4096 btrfs_abort_transaction(trans, ret);
4097 goto out;
4098 }
4099
4100 leaf = path->nodes[0];
4101 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
4102 index = key.offset;
4103 }
4104 btrfs_release_path(path);
4105
4106 ret = btrfs_delete_delayed_dir_index(trans, BTRFS_I(dir), index);
4107 if (ret) {
4108 btrfs_abort_transaction(trans, ret);
4109 goto out;
4110 }
4111
4112 btrfs_i_size_write(BTRFS_I(dir), dir->i_size - name_len * 2);
4113 inode_inc_iversion(dir);
4114 dir->i_mtime = dir->i_ctime = current_time(dir);
4115 ret = btrfs_update_inode_fallback(trans, root, dir);
4116 if (ret)
4117 btrfs_abort_transaction(trans, ret);
4118 out:
4119 btrfs_free_path(path);
4120 return ret;
4121 }
4122
4123 /*
4124 * Helper to check if the subvolume references other subvolumes or if it's
4125 * default.
4126 */
4127 static noinline int may_destroy_subvol(struct btrfs_root *root)
4128 {
4129 struct btrfs_fs_info *fs_info = root->fs_info;
4130 struct btrfs_path *path;
4131 struct btrfs_dir_item *di;
4132 struct btrfs_key key;
4133 u64 dir_id;
4134 int ret;
4135
4136 path = btrfs_alloc_path();
4137 if (!path)
4138 return -ENOMEM;
4139
4140 /* Make sure this root isn't set as the default subvol */
4141 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4142 di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
4143 dir_id, "default", 7, 0);
4144 if (di && !IS_ERR(di)) {
4145 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
4146 if (key.objectid == root->root_key.objectid) {
4147 ret = -EPERM;
4148 btrfs_err(fs_info,
4149 "deleting default subvolume %llu is not allowed",
4150 key.objectid);
4151 goto out;
4152 }
4153 btrfs_release_path(path);
4154 }
4155
4156 key.objectid = root->root_key.objectid;
4157 key.type = BTRFS_ROOT_REF_KEY;
4158 key.offset = (u64)-1;
4159
4160 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
4161 if (ret < 0)
4162 goto out;
4163 BUG_ON(ret == 0);
4164
4165 ret = 0;
4166 if (path->slots[0] > 0) {
4167 path->slots[0]--;
4168 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
4169 if (key.objectid == root->root_key.objectid &&
4170 key.type == BTRFS_ROOT_REF_KEY)
4171 ret = -ENOTEMPTY;
4172 }
4173 out:
4174 btrfs_free_path(path);
4175 return ret;
4176 }
4177
4178 /* Delete all dentries for inodes belonging to the root */
4179 static void btrfs_prune_dentries(struct btrfs_root *root)
4180 {
4181 struct btrfs_fs_info *fs_info = root->fs_info;
4182 struct rb_node *node;
4183 struct rb_node *prev;
4184 struct btrfs_inode *entry;
4185 struct inode *inode;
4186 u64 objectid = 0;
4187
4188 if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
4189 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4190
4191 spin_lock(&root->inode_lock);
4192 again:
4193 node = root->inode_tree.rb_node;
4194 prev = NULL;
4195 while (node) {
4196 prev = node;
4197 entry = rb_entry(node, struct btrfs_inode, rb_node);
4198
4199 if (objectid < btrfs_ino(entry))
4200 node = node->rb_left;
4201 else if (objectid > btrfs_ino(entry))
4202 node = node->rb_right;
4203 else
4204 break;
4205 }
4206 if (!node) {
4207 while (prev) {
4208 entry = rb_entry(prev, struct btrfs_inode, rb_node);
4209 if (objectid <= btrfs_ino(entry)) {
4210 node = prev;
4211 break;
4212 }
4213 prev = rb_next(prev);
4214 }
4215 }
4216 while (node) {
4217 entry = rb_entry(node, struct btrfs_inode, rb_node);
4218 objectid = btrfs_ino(entry) + 1;
4219 inode = igrab(&entry->vfs_inode);
4220 if (inode) {
4221 spin_unlock(&root->inode_lock);
4222 if (atomic_read(&inode->i_count) > 1)
4223 d_prune_aliases(inode);
4224 /*
4225 * btrfs_drop_inode will have it removed from the inode
4226 * cache when its usage count hits zero.
4227 */
4228 iput(inode);
4229 cond_resched();
4230 spin_lock(&root->inode_lock);
4231 goto again;
4232 }
4233
4234 if (cond_resched_lock(&root->inode_lock))
4235 goto again;
4236
4237 node = rb_next(node);
4238 }
4239 spin_unlock(&root->inode_lock);
4240 }
4241
4242 int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
4243 {
4244 struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
4245 struct btrfs_root *root = BTRFS_I(dir)->root;
4246 struct inode *inode = d_inode(dentry);
4247 struct btrfs_root *dest = BTRFS_I(inode)->root;
4248 struct btrfs_trans_handle *trans;
4249 struct btrfs_block_rsv block_rsv;
4250 u64 root_flags;
4251 int ret;
4252 int err;
4253
4254 /*
4255 * Don't allow to delete a subvolume with send in progress. This is
4256 * inside the inode lock so the error handling that has to drop the bit
4257 * again is not run concurrently.
4258 */
4259 spin_lock(&dest->root_item_lock);
4260 if (dest->send_in_progress) {
4261 spin_unlock(&dest->root_item_lock);
4262 btrfs_warn(fs_info,
4263 "attempt to delete subvolume %llu during send",
4264 dest->root_key.objectid);
4265 return -EPERM;
4266 }
4267 root_flags = btrfs_root_flags(&dest->root_item);
4268 btrfs_set_root_flags(&dest->root_item,
4269 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
4270 spin_unlock(&dest->root_item_lock);
4271
4272 down_write(&fs_info->subvol_sem);
4273
4274 err = may_destroy_subvol(dest);
4275 if (err)
4276 goto out_up_write;
4277
4278 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
4279 /*
4280 * One for dir inode,
4281 * two for dir entries,
4282 * two for root ref/backref.
4283 */
4284 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true);
4285 if (err)
4286 goto out_up_write;
4287
4288 trans = btrfs_start_transaction(root, 0);
4289 if (IS_ERR(trans)) {
4290 err = PTR_ERR(trans);
4291 goto out_release;
4292 }
4293 trans->block_rsv = &block_rsv;
4294 trans->bytes_reserved = block_rsv.size;
4295
4296 btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
4297
4298 ret = btrfs_unlink_subvol(trans, dir, dest->root_key.objectid,
4299 dentry->d_name.name, dentry->d_name.len);
4300 if (ret) {
4301 err = ret;
4302 btrfs_abort_transaction(trans, ret);
4303 goto out_end_trans;
4304 }
4305
4306 btrfs_record_root_in_trans(trans, dest);
4307
4308 memset(&dest->root_item.drop_progress, 0,
4309 sizeof(dest->root_item.drop_progress));
4310 dest->root_item.drop_level = 0;
4311 btrfs_set_root_refs(&dest->root_item, 0);
4312
4313 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
4314 ret = btrfs_insert_orphan_item(trans,
4315 fs_info->tree_root,
4316 dest->root_key.objectid);
4317 if (ret) {
4318 btrfs_abort_transaction(trans, ret);
4319 err = ret;
4320 goto out_end_trans;
4321 }
4322 }
4323
4324 ret = btrfs_uuid_tree_remove(trans, dest->root_item.uuid,
4325 BTRFS_UUID_KEY_SUBVOL,
4326 dest->root_key.objectid);
4327 if (ret && ret != -ENOENT) {
4328 btrfs_abort_transaction(trans, ret);
4329 err = ret;
4330 goto out_end_trans;
4331 }
4332 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
4333 ret = btrfs_uuid_tree_remove(trans,
4334 dest->root_item.received_uuid,
4335 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4336 dest->root_key.objectid);
4337 if (ret && ret != -ENOENT) {
4338 btrfs_abort_transaction(trans, ret);
4339 err = ret;
4340 goto out_end_trans;
4341 }
4342 }
4343
4344 out_end_trans:
4345 trans->block_rsv = NULL;
4346 trans->bytes_reserved = 0;
4347 ret = btrfs_end_transaction(trans);
4348 if (ret && !err)
4349 err = ret;
4350 inode->i_flags |= S_DEAD;
4351 out_release:
4352 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
4353 out_up_write:
4354 up_write(&fs_info->subvol_sem);
4355 if (err) {
4356 spin_lock(&dest->root_item_lock);
4357 root_flags = btrfs_root_flags(&dest->root_item);
4358 btrfs_set_root_flags(&dest->root_item,
4359 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
4360 spin_unlock(&dest->root_item_lock);
4361 } else {
4362 d_invalidate(dentry);
4363 btrfs_prune_dentries(dest);
4364 ASSERT(dest->send_in_progress == 0);
4365
4366 /* the last ref */
4367 if (dest->ino_cache_inode) {
4368 iput(dest->ino_cache_inode);
4369 dest->ino_cache_inode = NULL;
4370 }
4371 }
4372
4373 return err;
4374 }
4375
4376 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
4377 {
4378 struct inode *inode = d_inode(dentry);
4379 int err = 0;
4380 struct btrfs_root *root = BTRFS_I(dir)->root;
4381 struct btrfs_trans_handle *trans;
4382 u64 last_unlink_trans;
4383
4384 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
4385 return -ENOTEMPTY;
4386 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID)
4387 return btrfs_delete_subvolume(dir, dentry);
4388
4389 trans = __unlink_start_trans(dir);
4390 if (IS_ERR(trans))
4391 return PTR_ERR(trans);
4392
4393 if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
4394 err = btrfs_unlink_subvol(trans, dir,
4395 BTRFS_I(inode)->location.objectid,
4396 dentry->d_name.name,
4397 dentry->d_name.len);
4398 goto out;
4399 }
4400
4401 err = btrfs_orphan_add(trans, BTRFS_I(inode));
4402 if (err)
4403 goto out;
4404
4405 last_unlink_trans = BTRFS_I(inode)->last_unlink_trans;
4406
4407 /* now the directory is empty */
4408 err = btrfs_unlink_inode(trans, root, BTRFS_I(dir),
4409 BTRFS_I(d_inode(dentry)), dentry->d_name.name,
4410 dentry->d_name.len);
4411 if (!err) {
4412 btrfs_i_size_write(BTRFS_I(inode), 0);
4413 /*
4414 * Propagate the last_unlink_trans value of the deleted dir to
4415 * its parent directory. This is to prevent an unrecoverable
4416 * log tree in the case we do something like this:
4417 * 1) create dir foo
4418 * 2) create snapshot under dir foo
4419 * 3) delete the snapshot
4420 * 4) rmdir foo
4421 * 5) mkdir foo
4422 * 6) fsync foo or some file inside foo
4423 */
4424 if (last_unlink_trans >= trans->transid)
4425 BTRFS_I(dir)->last_unlink_trans = last_unlink_trans;
4426 }
4427 out:
4428 btrfs_end_transaction(trans);
4429 btrfs_btree_balance_dirty(root->fs_info);
4430
4431 return err;
4432 }
4433
4434 static int truncate_space_check(struct btrfs_trans_handle *trans,
4435 struct btrfs_root *root,
4436 u64 bytes_deleted)
4437 {
4438 struct btrfs_fs_info *fs_info = root->fs_info;
4439 int ret;
4440
4441 /*
4442 * This is only used to apply pressure to the enospc system, we don't
4443 * intend to use this reservation at all.
4444 */
4445 bytes_deleted = btrfs_csum_bytes_to_leaves(fs_info, bytes_deleted);
4446 bytes_deleted *= fs_info->nodesize;
4447 ret = btrfs_block_rsv_add(root, &fs_info->trans_block_rsv,
4448 bytes_deleted, BTRFS_RESERVE_NO_FLUSH);
4449 if (!ret) {
4450 trace_btrfs_space_reservation(fs_info, "transaction",
4451 trans->transid,
4452 bytes_deleted, 1);
4453 trans->bytes_reserved += bytes_deleted;
4454 }
4455 return ret;
4456
4457 }
4458
4459 /*
4460 * Return this if we need to call truncate_block for the last bit of the
4461 * truncate.
4462 */
4463 #define NEED_TRUNCATE_BLOCK 1
4464
4465 /*
4466 * this can truncate away extent items, csum items and directory items.
4467 * It starts at a high offset and removes keys until it can't find
4468 * any higher than new_size
4469 *
4470 * csum items that cross the new i_size are truncated to the new size
4471 * as well.
4472 *
4473 * min_type is the minimum key type to truncate down to. If set to 0, this
4474 * will kill all the items on this inode, including the INODE_ITEM_KEY.
4475 */
4476 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
4477 struct btrfs_root *root,
4478 struct inode *inode,
4479 u64 new_size, u32 min_type)
4480 {
4481 struct btrfs_fs_info *fs_info = root->fs_info;
4482 struct btrfs_path *path;
4483 struct extent_buffer *leaf;
4484 struct btrfs_file_extent_item *fi;
4485 struct btrfs_key key;
4486 struct btrfs_key found_key;
4487 u64 extent_start = 0;
4488 u64 extent_num_bytes = 0;
4489 u64 extent_offset = 0;
4490 u64 item_end = 0;
4491 u64 last_size = new_size;
4492 u32 found_type = (u8)-1;
4493 int found_extent;
4494 int del_item;
4495 int pending_del_nr = 0;
4496 int pending_del_slot = 0;
4497 int extent_type = -1;
4498 int ret;
4499 u64 ino = btrfs_ino(BTRFS_I(inode));
4500 u64 bytes_deleted = 0;
4501 bool be_nice = false;
4502 bool should_throttle = false;
4503 bool should_end = false;
4504
4505 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
4506
4507 /*
4508 * for non-free space inodes and ref cows, we want to back off from
4509 * time to time
4510 */
4511 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) &&
4512 test_bit(BTRFS_ROOT_REF_COWS, &root->state))
4513 be_nice = true;
4514
4515 path = btrfs_alloc_path();
4516 if (!path)
4517 return -ENOMEM;
4518 path->reada = READA_BACK;
4519
4520 /*
4521 * We want to drop from the next block forward in case this new size is
4522 * not block aligned since we will be keeping the last block of the
4523 * extent just the way it is.
4524 */
4525 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
4526 root == fs_info->tree_root)
4527 btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size,
4528 fs_info->sectorsize),
4529 (u64)-1, 0);
4530
4531 /*
4532 * This function is also used to drop the items in the log tree before
4533 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
4534 * it is used to drop the loged items. So we shouldn't kill the delayed
4535 * items.
4536 */
4537 if (min_type == 0 && root == BTRFS_I(inode)->root)
4538 btrfs_kill_delayed_inode_items(BTRFS_I(inode));
4539
4540 key.objectid = ino;
4541 key.offset = (u64)-1;
4542 key.type = (u8)-1;
4543
4544 search_again:
4545 /*
4546 * with a 16K leaf size and 128MB extents, you can actually queue
4547 * up a huge file in a single leaf. Most of the time that
4548 * bytes_deleted is > 0, it will be huge by the time we get here
4549 */
4550 if (be_nice && bytes_deleted > SZ_32M &&
4551 btrfs_should_end_transaction(trans)) {
4552 ret = -EAGAIN;
4553 goto out;
4554 }
4555
4556 path->leave_spinning = 1;
4557 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
4558 if (ret < 0)
4559 goto out;
4560
4561 if (ret > 0) {
4562 ret = 0;
4563 /* there are no items in the tree for us to truncate, we're
4564 * done
4565 */
4566 if (path->slots[0] == 0)
4567 goto out;
4568 path->slots[0]--;
4569 }
4570
4571 while (1) {
4572 fi = NULL;
4573 leaf = path->nodes[0];
4574 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4575 found_type = found_key.type;
4576
4577 if (found_key.objectid != ino)
4578 break;
4579
4580 if (found_type < min_type)
4581 break;
4582
4583 item_end = found_key.offset;
4584 if (found_type == BTRFS_EXTENT_DATA_KEY) {
4585 fi = btrfs_item_ptr(leaf, path->slots[0],
4586 struct btrfs_file_extent_item);
4587 extent_type = btrfs_file_extent_type(leaf, fi);
4588 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4589 item_end +=
4590 btrfs_file_extent_num_bytes(leaf, fi);
4591
4592 trace_btrfs_truncate_show_fi_regular(
4593 BTRFS_I(inode), leaf, fi,
4594 found_key.offset);
4595 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4596 item_end += btrfs_file_extent_ram_bytes(leaf,
4597 fi);
4598
4599 trace_btrfs_truncate_show_fi_inline(
4600 BTRFS_I(inode), leaf, fi, path->slots[0],
4601 found_key.offset);
4602 }
4603 item_end--;
4604 }
4605 if (found_type > min_type) {
4606 del_item = 1;
4607 } else {
4608 if (item_end < new_size)
4609 break;
4610 if (found_key.offset >= new_size)
4611 del_item = 1;
4612 else
4613 del_item = 0;
4614 }
4615 found_extent = 0;
4616 /* FIXME, shrink the extent if the ref count is only 1 */
4617 if (found_type != BTRFS_EXTENT_DATA_KEY)
4618 goto delete;
4619
4620 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4621 u64 num_dec;
4622 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
4623 if (!del_item) {
4624 u64 orig_num_bytes =
4625 btrfs_file_extent_num_bytes(leaf, fi);
4626 extent_num_bytes = ALIGN(new_size -
4627 found_key.offset,
4628 fs_info->sectorsize);
4629 btrfs_set_file_extent_num_bytes(leaf, fi,
4630 extent_num_bytes);
4631 num_dec = (orig_num_bytes -
4632 extent_num_bytes);
4633 if (test_bit(BTRFS_ROOT_REF_COWS,
4634 &root->state) &&
4635 extent_start != 0)
4636 inode_sub_bytes(inode, num_dec);
4637 btrfs_mark_buffer_dirty(leaf);
4638 } else {
4639 extent_num_bytes =
4640 btrfs_file_extent_disk_num_bytes(leaf,
4641 fi);
4642 extent_offset = found_key.offset -
4643 btrfs_file_extent_offset(leaf, fi);
4644
4645 /* FIXME blocksize != 4096 */
4646 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4647 if (extent_start != 0) {
4648 found_extent = 1;
4649 if (test_bit(BTRFS_ROOT_REF_COWS,
4650 &root->state))
4651 inode_sub_bytes(inode, num_dec);
4652 }
4653 }
4654 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4655 /*
4656 * we can't truncate inline items that have had
4657 * special encodings
4658 */
4659 if (!del_item &&
4660 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4661 btrfs_file_extent_other_encoding(leaf, fi) == 0 &&
4662 btrfs_file_extent_compression(leaf, fi) == 0) {
4663 u32 size = (u32)(new_size - found_key.offset);
4664
4665 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
4666 size = btrfs_file_extent_calc_inline_size(size);
4667 btrfs_truncate_item(root->fs_info, path, size, 1);
4668 } else if (!del_item) {
4669 /*
4670 * We have to bail so the last_size is set to
4671 * just before this extent.
4672 */
4673 ret = NEED_TRUNCATE_BLOCK;
4674 break;
4675 }
4676
4677 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state))
4678 inode_sub_bytes(inode, item_end + 1 - new_size);
4679 }
4680 delete:
4681 if (del_item)
4682 last_size = found_key.offset;
4683 else
4684 last_size = new_size;
4685 if (del_item) {
4686 if (!pending_del_nr) {
4687 /* no pending yet, add ourselves */
4688 pending_del_slot = path->slots[0];
4689 pending_del_nr = 1;
4690 } else if (pending_del_nr &&
4691 path->slots[0] + 1 == pending_del_slot) {
4692 /* hop on the pending chunk */
4693 pending_del_nr++;
4694 pending_del_slot = path->slots[0];
4695 } else {
4696 BUG();
4697 }
4698 } else {
4699 break;
4700 }
4701 should_throttle = false;
4702
4703 if (found_extent &&
4704 (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
4705 root == fs_info->tree_root)) {
4706 btrfs_set_path_blocking(path);
4707 bytes_deleted += extent_num_bytes;
4708 ret = btrfs_free_extent(trans, root, extent_start,
4709 extent_num_bytes, 0,
4710 btrfs_header_owner(leaf),
4711 ino, extent_offset);
4712 if (ret) {
4713 btrfs_abort_transaction(trans, ret);
4714 break;
4715 }
4716 if (btrfs_should_throttle_delayed_refs(trans))
4717 btrfs_async_run_delayed_refs(fs_info,
4718 trans->delayed_ref_updates * 2,
4719 trans->transid, 0);
4720 if (be_nice) {
4721 if (truncate_space_check(trans, root,
4722 extent_num_bytes)) {
4723 should_end = true;
4724 }
4725 if (btrfs_should_throttle_delayed_refs(trans))
4726 should_throttle = true;
4727 }
4728 }
4729
4730 if (found_type == BTRFS_INODE_ITEM_KEY)
4731 break;
4732
4733 if (path->slots[0] == 0 ||
4734 path->slots[0] != pending_del_slot ||
4735 should_throttle || should_end) {
4736 if (pending_del_nr) {
4737 ret = btrfs_del_items(trans, root, path,
4738 pending_del_slot,
4739 pending_del_nr);
4740 if (ret) {
4741 btrfs_abort_transaction(trans, ret);
4742 break;
4743 }
4744 pending_del_nr = 0;
4745 }
4746 btrfs_release_path(path);
4747 if (should_throttle) {
4748 unsigned long updates = trans->delayed_ref_updates;
4749 if (updates) {
4750 trans->delayed_ref_updates = 0;
4751 ret = btrfs_run_delayed_refs(trans,
4752 updates * 2);
4753 if (ret)
4754 break;
4755 }
4756 }
4757 /*
4758 * if we failed to refill our space rsv, bail out
4759 * and let the transaction restart
4760 */
4761 if (should_end) {
4762 ret = -EAGAIN;
4763 break;
4764 }
4765 goto search_again;
4766 } else {
4767 path->slots[0]--;
4768 }
4769 }
4770 out:
4771 if (ret >= 0 && pending_del_nr) {
4772 int err;
4773
4774 err = btrfs_del_items(trans, root, path, pending_del_slot,
4775 pending_del_nr);
4776 if (err) {
4777 btrfs_abort_transaction(trans, err);
4778 ret = err;
4779 }
4780 }
4781 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4782 ASSERT(last_size >= new_size);
4783 if (!ret && last_size > new_size)
4784 last_size = new_size;
4785 btrfs_ordered_update_i_size(inode, last_size, NULL);
4786 }
4787
4788 btrfs_free_path(path);
4789
4790 if (be_nice && bytes_deleted > SZ_32M && (ret >= 0 || ret == -EAGAIN)) {
4791 unsigned long updates = trans->delayed_ref_updates;
4792 int err;
4793
4794 if (updates) {
4795 trans->delayed_ref_updates = 0;
4796 err = btrfs_run_delayed_refs(trans, updates * 2);
4797 if (err)
4798 ret = err;
4799 }
4800 }
4801 return ret;
4802 }
4803
4804 /*
4805 * btrfs_truncate_block - read, zero a chunk and write a block
4806 * @inode - inode that we're zeroing
4807 * @from - the offset to start zeroing
4808 * @len - the length to zero, 0 to zero the entire range respective to the
4809 * offset
4810 * @front - zero up to the offset instead of from the offset on
4811 *
4812 * This will find the block for the "from" offset and cow the block and zero the
4813 * part we want to zero. This is used with truncate and hole punching.
4814 */
4815 int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
4816 int front)
4817 {
4818 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4819 struct address_space *mapping = inode->i_mapping;
4820 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4821 struct btrfs_ordered_extent *ordered;
4822 struct extent_state *cached_state = NULL;
4823 struct extent_changeset *data_reserved = NULL;
4824 char *kaddr;
4825 u32 blocksize = fs_info->sectorsize;
4826 pgoff_t index = from >> PAGE_SHIFT;
4827 unsigned offset = from & (blocksize - 1);
4828 struct page *page;
4829 gfp_t mask = btrfs_alloc_write_mask(mapping);
4830 int ret = 0;
4831 u64 block_start;
4832 u64 block_end;
4833
4834 if (IS_ALIGNED(offset, blocksize) &&
4835 (!len || IS_ALIGNED(len, blocksize)))
4836 goto out;
4837
4838 block_start = round_down(from, blocksize);
4839 block_end = block_start + blocksize - 1;
4840
4841 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
4842 block_start, blocksize);
4843 if (ret)
4844 goto out;
4845
4846 again:
4847 page = find_or_create_page(mapping, index, mask);
4848 if (!page) {
4849 btrfs_delalloc_release_space(inode, data_reserved,
4850 block_start, blocksize, true);
4851 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true);
4852 ret = -ENOMEM;
4853 goto out;
4854 }
4855
4856 if (!PageUptodate(page)) {
4857 ret = btrfs_readpage(NULL, page);
4858 lock_page(page);
4859 if (page->mapping != mapping) {
4860 unlock_page(page);
4861 put_page(page);
4862 goto again;
4863 }
4864 if (!PageUptodate(page)) {
4865 ret = -EIO;
4866 goto out_unlock;
4867 }
4868 }
4869 wait_on_page_writeback(page);
4870
4871 lock_extent_bits(io_tree, block_start, block_end, &cached_state);
4872 set_page_extent_mapped(page);
4873
4874 ordered = btrfs_lookup_ordered_extent(inode, block_start);
4875 if (ordered) {
4876 unlock_extent_cached(io_tree, block_start, block_end,
4877 &cached_state);
4878 unlock_page(page);
4879 put_page(page);
4880 btrfs_start_ordered_extent(inode, ordered, 1);
4881 btrfs_put_ordered_extent(ordered);
4882 goto again;
4883 }
4884
4885 clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end,
4886 EXTENT_DIRTY | EXTENT_DELALLOC |
4887 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4888 0, 0, &cached_state);
4889
4890 ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 0,
4891 &cached_state, 0);
4892 if (ret) {
4893 unlock_extent_cached(io_tree, block_start, block_end,
4894 &cached_state);
4895 goto out_unlock;
4896 }
4897
4898 if (offset != blocksize) {
4899 if (!len)
4900 len = blocksize - offset;
4901 kaddr = kmap(page);
4902 if (front)
4903 memset(kaddr + (block_start - page_offset(page)),
4904 0, offset);
4905 else
4906 memset(kaddr + (block_start - page_offset(page)) + offset,
4907 0, len);
4908 flush_dcache_page(page);
4909 kunmap(page);
4910 }
4911 ClearPageChecked(page);
4912 set_page_dirty(page);
4913 unlock_extent_cached(io_tree, block_start, block_end, &cached_state);
4914
4915 out_unlock:
4916 if (ret)
4917 btrfs_delalloc_release_space(inode, data_reserved, block_start,
4918 blocksize, true);
4919 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0));
4920 unlock_page(page);
4921 put_page(page);
4922 out:
4923 extent_changeset_free(data_reserved);
4924 return ret;
4925 }
4926
4927 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode,
4928 u64 offset, u64 len)
4929 {
4930 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4931 struct btrfs_trans_handle *trans;
4932 int ret;
4933
4934 /*
4935 * Still need to make sure the inode looks like it's been updated so
4936 * that any holes get logged if we fsync.
4937 */
4938 if (btrfs_fs_incompat(fs_info, NO_HOLES)) {
4939 BTRFS_I(inode)->last_trans = fs_info->generation;
4940 BTRFS_I(inode)->last_sub_trans = root->log_transid;
4941 BTRFS_I(inode)->last_log_commit = root->last_log_commit;
4942 return 0;
4943 }
4944
4945 /*
4946 * 1 - for the one we're dropping
4947 * 1 - for the one we're adding
4948 * 1 - for updating the inode.
4949 */
4950 trans = btrfs_start_transaction(root, 3);
4951 if (IS_ERR(trans))
4952 return PTR_ERR(trans);
4953
4954 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1);
4955 if (ret) {
4956 btrfs_abort_transaction(trans, ret);
4957 btrfs_end_transaction(trans);
4958 return ret;
4959 }
4960
4961 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)),
4962 offset, 0, 0, len, 0, len, 0, 0, 0);
4963 if (ret)
4964 btrfs_abort_transaction(trans, ret);
4965 else
4966 btrfs_update_inode(trans, root, inode);
4967 btrfs_end_transaction(trans);
4968 return ret;
4969 }
4970
4971 /*
4972 * This function puts in dummy file extents for the area we're creating a hole
4973 * for. So if we are truncating this file to a larger size we need to insert
4974 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4975 * the range between oldsize and size
4976 */
4977 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4978 {
4979 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4980 struct btrfs_root *root = BTRFS_I(inode)->root;
4981 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4982 struct extent_map *em = NULL;
4983 struct extent_state *cached_state = NULL;
4984 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4985 u64 hole_start = ALIGN(oldsize, fs_info->sectorsize);
4986 u64 block_end = ALIGN(size, fs_info->sectorsize);
4987 u64 last_byte;
4988 u64 cur_offset;
4989 u64 hole_size;
4990 int err = 0;
4991
4992 /*
4993 * If our size started in the middle of a block we need to zero out the
4994 * rest of the block before we expand the i_size, otherwise we could
4995 * expose stale data.
4996 */
4997 err = btrfs_truncate_block(inode, oldsize, 0, 0);
4998 if (err)
4999 return err;
5000
5001 if (size <= hole_start)
5002 return 0;
5003
5004 while (1) {
5005 struct btrfs_ordered_extent *ordered;
5006
5007 lock_extent_bits(io_tree, hole_start, block_end - 1,
5008 &cached_state);
5009 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start,
5010 block_end - hole_start);
5011 if (!ordered)
5012 break;
5013 unlock_extent_cached(io_tree, hole_start, block_end - 1,
5014 &cached_state);
5015 btrfs_start_ordered_extent(inode, ordered, 1);
5016 btrfs_put_ordered_extent(ordered);
5017 }
5018
5019 cur_offset = hole_start;
5020 while (1) {
5021 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset,
5022 block_end - cur_offset, 0);
5023 if (IS_ERR(em)) {
5024 err = PTR_ERR(em);
5025 em = NULL;
5026 break;
5027 }
5028 last_byte = min(extent_map_end(em), block_end);
5029 last_byte = ALIGN(last_byte, fs_info->sectorsize);
5030 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
5031 struct extent_map *hole_em;
5032 hole_size = last_byte - cur_offset;
5033
5034 err = maybe_insert_hole(root, inode, cur_offset,
5035 hole_size);
5036 if (err)
5037 break;
5038 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
5039 cur_offset + hole_size - 1, 0);
5040 hole_em = alloc_extent_map();
5041 if (!hole_em) {
5042 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5043 &BTRFS_I(inode)->runtime_flags);
5044 goto next;
5045 }
5046 hole_em->start = cur_offset;
5047 hole_em->len = hole_size;
5048 hole_em->orig_start = cur_offset;
5049
5050 hole_em->block_start = EXTENT_MAP_HOLE;
5051 hole_em->block_len = 0;
5052 hole_em->orig_block_len = 0;
5053 hole_em->ram_bytes = hole_size;
5054 hole_em->bdev = fs_info->fs_devices->latest_bdev;
5055 hole_em->compress_type = BTRFS_COMPRESS_NONE;
5056 hole_em->generation = fs_info->generation;
5057
5058 while (1) {
5059 write_lock(&em_tree->lock);
5060 err = add_extent_mapping(em_tree, hole_em, 1);
5061 write_unlock(&em_tree->lock);
5062 if (err != -EEXIST)
5063 break;
5064 btrfs_drop_extent_cache(BTRFS_I(inode),
5065 cur_offset,
5066 cur_offset +
5067 hole_size - 1, 0);
5068 }
5069 free_extent_map(hole_em);
5070 }
5071 next:
5072 free_extent_map(em);
5073 em = NULL;
5074 cur_offset = last_byte;
5075 if (cur_offset >= block_end)
5076 break;
5077 }
5078 free_extent_map(em);
5079 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state);
5080 return err;
5081 }
5082
5083 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
5084 {
5085 struct btrfs_root *root = BTRFS_I(inode)->root;
5086 struct btrfs_trans_handle *trans;
5087 loff_t oldsize = i_size_read(inode);
5088 loff_t newsize = attr->ia_size;
5089 int mask = attr->ia_valid;
5090 int ret;
5091
5092 /*
5093 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
5094 * special case where we need to update the times despite not having
5095 * these flags set. For all other operations the VFS set these flags
5096 * explicitly if it wants a timestamp update.
5097 */
5098 if (newsize != oldsize) {
5099 inode_inc_iversion(inode);
5100 if (!(mask & (ATTR_CTIME | ATTR_MTIME)))
5101 inode->i_ctime = inode->i_mtime =
5102 current_time(inode);
5103 }
5104
5105 if (newsize > oldsize) {
5106 /*
5107 * Don't do an expanding truncate while snapshotting is ongoing.
5108 * This is to ensure the snapshot captures a fully consistent
5109 * state of this file - if the snapshot captures this expanding
5110 * truncation, it must capture all writes that happened before
5111 * this truncation.
5112 */
5113 btrfs_wait_for_snapshot_creation(root);
5114 ret = btrfs_cont_expand(inode, oldsize, newsize);
5115 if (ret) {
5116 btrfs_end_write_no_snapshotting(root);
5117 return ret;
5118 }
5119
5120 trans = btrfs_start_transaction(root, 1);
5121 if (IS_ERR(trans)) {
5122 btrfs_end_write_no_snapshotting(root);
5123 return PTR_ERR(trans);
5124 }
5125
5126 i_size_write(inode, newsize);
5127 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
5128 pagecache_isize_extended(inode, oldsize, newsize);
5129 ret = btrfs_update_inode(trans, root, inode);
5130 btrfs_end_write_no_snapshotting(root);
5131 btrfs_end_transaction(trans);
5132 } else {
5133
5134 /*
5135 * We're truncating a file that used to have good data down to
5136 * zero. Make sure it gets into the ordered flush list so that
5137 * any new writes get down to disk quickly.
5138 */
5139 if (newsize == 0)
5140 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
5141 &BTRFS_I(inode)->runtime_flags);
5142
5143 truncate_setsize(inode, newsize);
5144
5145 /* Disable nonlocked read DIO to avoid the end less truncate */
5146 btrfs_inode_block_unlocked_dio(BTRFS_I(inode));
5147 inode_dio_wait(inode);
5148 btrfs_inode_resume_unlocked_dio(BTRFS_I(inode));
5149
5150 ret = btrfs_truncate(inode, newsize == oldsize);
5151 if (ret && inode->i_nlink) {
5152 int err;
5153
5154 /*
5155 * Truncate failed, so fix up the in-memory size. We
5156 * adjusted disk_i_size down as we removed extents, so
5157 * wait for disk_i_size to be stable and then update the
5158 * in-memory size to match.
5159 */
5160 err = btrfs_wait_ordered_range(inode, 0, (u64)-1);
5161 if (err)
5162 return err;
5163 i_size_write(inode, BTRFS_I(inode)->disk_i_size);
5164 }
5165 }
5166
5167 return ret;
5168 }
5169
5170 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
5171 {
5172 struct inode *inode = d_inode(dentry);
5173 struct btrfs_root *root = BTRFS_I(inode)->root;
5174 int err;
5175
5176 if (btrfs_root_readonly(root))
5177 return -EROFS;
5178
5179 err = setattr_prepare(dentry, attr);
5180 if (err)
5181 return err;
5182
5183 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
5184 err = btrfs_setsize(inode, attr);
5185 if (err)
5186 return err;
5187 }
5188
5189 if (attr->ia_valid) {
5190 setattr_copy(inode, attr);
5191 inode_inc_iversion(inode);
5192 err = btrfs_dirty_inode(inode);
5193
5194 if (!err && attr->ia_valid & ATTR_MODE)
5195 err = posix_acl_chmod(inode, inode->i_mode);
5196 }
5197
5198 return err;
5199 }
5200
5201 /*
5202 * While truncating the inode pages during eviction, we get the VFS calling
5203 * btrfs_invalidatepage() against each page of the inode. This is slow because
5204 * the calls to btrfs_invalidatepage() result in a huge amount of calls to
5205 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting
5206 * extent_state structures over and over, wasting lots of time.
5207 *
5208 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all
5209 * those expensive operations on a per page basis and do only the ordered io
5210 * finishing, while we release here the extent_map and extent_state structures,
5211 * without the excessive merging and splitting.
5212 */
5213 static void evict_inode_truncate_pages(struct inode *inode)
5214 {
5215 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
5216 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree;
5217 struct rb_node *node;
5218
5219 ASSERT(inode->i_state & I_FREEING);
5220 truncate_inode_pages_final(&inode->i_data);
5221
5222 write_lock(&map_tree->lock);
5223 while (!RB_EMPTY_ROOT(&map_tree->map.rb_root)) {
5224 struct extent_map *em;
5225
5226 node = rb_first_cached(&map_tree->map);
5227 em = rb_entry(node, struct extent_map, rb_node);
5228 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
5229 clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
5230 remove_extent_mapping(map_tree, em);
5231 free_extent_map(em);
5232 if (need_resched()) {
5233 write_unlock(&map_tree->lock);
5234 cond_resched();
5235 write_lock(&map_tree->lock);
5236 }
5237 }
5238 write_unlock(&map_tree->lock);
5239
5240 /*
5241 * Keep looping until we have no more ranges in the io tree.
5242 * We can have ongoing bios started by readpages (called from readahead)
5243 * that have their endio callback (extent_io.c:end_bio_extent_readpage)
5244 * still in progress (unlocked the pages in the bio but did not yet
5245 * unlocked the ranges in the io tree). Therefore this means some
5246 * ranges can still be locked and eviction started because before
5247 * submitting those bios, which are executed by a separate task (work
5248 * queue kthread), inode references (inode->i_count) were not taken
5249 * (which would be dropped in the end io callback of each bio).
5250 * Therefore here we effectively end up waiting for those bios and
5251 * anyone else holding locked ranges without having bumped the inode's
5252 * reference count - if we don't do it, when they access the inode's
5253 * io_tree to unlock a range it may be too late, leading to an
5254 * use-after-free issue.
5255 */
5256 spin_lock(&io_tree->lock);
5257 while (!RB_EMPTY_ROOT(&io_tree->state)) {
5258 struct extent_state *state;
5259 struct extent_state *cached_state = NULL;
5260 u64 start;
5261 u64 end;
5262
5263 node = rb_first(&io_tree->state);
5264 state = rb_entry(node, struct extent_state, rb_node);
5265 start = state->start;
5266 end = state->end;
5267 spin_unlock(&io_tree->lock);
5268
5269 lock_extent_bits(io_tree, start, end, &cached_state);
5270
5271 /*
5272 * If still has DELALLOC flag, the extent didn't reach disk,
5273 * and its reserved space won't be freed by delayed_ref.
5274 * So we need to free its reserved space here.
5275 * (Refer to comment in btrfs_invalidatepage, case 2)
5276 *
5277 * Note, end is the bytenr of last byte, so we need + 1 here.
5278 */
5279 if (state->state & EXTENT_DELALLOC)
5280 btrfs_qgroup_free_data(inode, NULL, start, end - start + 1);
5281
5282 clear_extent_bit(io_tree, start, end,
5283 EXTENT_LOCKED | EXTENT_DIRTY |
5284 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
5285 EXTENT_DEFRAG, 1, 1, &cached_state);
5286
5287 cond_resched();
5288 spin_lock(&io_tree->lock);
5289 }
5290 spin_unlock(&io_tree->lock);
5291 }
5292
5293 static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root,
5294 struct btrfs_block_rsv *rsv)
5295 {
5296 struct btrfs_fs_info *fs_info = root->fs_info;
5297 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5298 int failures = 0;
5299
5300 for (;;) {
5301 struct btrfs_trans_handle *trans;
5302 int ret;
5303
5304 ret = btrfs_block_rsv_refill(root, rsv, rsv->size,
5305 BTRFS_RESERVE_FLUSH_LIMIT);
5306
5307 if (ret && ++failures > 2) {
5308 btrfs_warn(fs_info,
5309 "could not allocate space for a delete; will truncate on mount");
5310 return ERR_PTR(-ENOSPC);
5311 }
5312
5313 trans = btrfs_join_transaction(root);
5314 if (IS_ERR(trans) || !ret)
5315 return trans;
5316
5317 /*
5318 * Try to steal from the global reserve if there is space for
5319 * it.
5320 */
5321 if (!btrfs_check_space_for_delayed_refs(trans) &&
5322 !btrfs_block_rsv_migrate(global_rsv, rsv, rsv->size, false))
5323 return trans;
5324
5325 /* If not, commit and try again. */
5326 ret = btrfs_commit_transaction(trans);
5327 if (ret)
5328 return ERR_PTR(ret);
5329 }
5330 }
5331
5332 void btrfs_evict_inode(struct inode *inode)
5333 {
5334 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5335 struct btrfs_trans_handle *trans;
5336 struct btrfs_root *root = BTRFS_I(inode)->root;
5337 struct btrfs_block_rsv *rsv;
5338 int ret;
5339
5340 trace_btrfs_inode_evict(inode);
5341
5342 if (!root) {
5343 clear_inode(inode);
5344 return;
5345 }
5346
5347 evict_inode_truncate_pages(inode);
5348
5349 if (inode->i_nlink &&
5350 ((btrfs_root_refs(&root->root_item) != 0 &&
5351 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) ||
5352 btrfs_is_free_space_inode(BTRFS_I(inode))))
5353 goto no_delete;
5354
5355 if (is_bad_inode(inode))
5356 goto no_delete;
5357
5358 btrfs_free_io_failure_record(BTRFS_I(inode), 0, (u64)-1);
5359
5360 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
5361 goto no_delete;
5362
5363 if (inode->i_nlink > 0) {
5364 BUG_ON(btrfs_root_refs(&root->root_item) != 0 &&
5365 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID);
5366 goto no_delete;
5367 }
5368
5369 ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode));
5370 if (ret)
5371 goto no_delete;
5372
5373 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
5374 if (!rsv)
5375 goto no_delete;
5376 rsv->size = btrfs_calc_trunc_metadata_size(fs_info, 1);
5377 rsv->failfast = 1;
5378
5379 btrfs_i_size_write(BTRFS_I(inode), 0);
5380
5381 while (1) {
5382 trans = evict_refill_and_join(root, rsv);
5383 if (IS_ERR(trans))
5384 goto free_rsv;
5385
5386 trans->block_rsv = rsv;
5387
5388 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
5389 trans->block_rsv = &fs_info->trans_block_rsv;
5390 btrfs_end_transaction(trans);
5391 btrfs_btree_balance_dirty(fs_info);
5392 if (ret && ret != -ENOSPC && ret != -EAGAIN)
5393 goto free_rsv;
5394 else if (!ret)
5395 break;
5396 }
5397
5398 /*
5399 * Errors here aren't a big deal, it just means we leave orphan items in
5400 * the tree. They will be cleaned up on the next mount. If the inode
5401 * number gets reused, cleanup deletes the orphan item without doing
5402 * anything, and unlink reuses the existing orphan item.
5403 *
5404 * If it turns out that we are dropping too many of these, we might want
5405 * to add a mechanism for retrying these after a commit.
5406 */
5407 trans = evict_refill_and_join(root, rsv);
5408 if (!IS_ERR(trans)) {
5409 trans->block_rsv = rsv;
5410 btrfs_orphan_del(trans, BTRFS_I(inode));
5411 trans->block_rsv = &fs_info->trans_block_rsv;
5412 btrfs_end_transaction(trans);
5413 }
5414
5415 if (!(root == fs_info->tree_root ||
5416 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
5417 btrfs_return_ino(root, btrfs_ino(BTRFS_I(inode)));
5418
5419 free_rsv:
5420 btrfs_free_block_rsv(fs_info, rsv);
5421 no_delete:
5422 /*
5423 * If we didn't successfully delete, the orphan item will still be in
5424 * the tree and we'll retry on the next mount. Again, we might also want
5425 * to retry these periodically in the future.
5426 */
5427 btrfs_remove_delayed_node(BTRFS_I(inode));
5428 clear_inode(inode);
5429 }
5430
5431 /*
5432 * this returns the key found in the dir entry in the location pointer.
5433 * If no dir entries were found, returns -ENOENT.
5434 * If found a corrupted location in dir entry, returns -EUCLEAN.
5435 */
5436 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
5437 struct btrfs_key *location)
5438 {
5439 const char *name = dentry->d_name.name;
5440 int namelen = dentry->d_name.len;
5441 struct btrfs_dir_item *di;
5442 struct btrfs_path *path;
5443 struct btrfs_root *root = BTRFS_I(dir)->root;
5444 int ret = 0;
5445
5446 path = btrfs_alloc_path();
5447 if (!path)
5448 return -ENOMEM;
5449
5450 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)),
5451 name, namelen, 0);
5452 if (IS_ERR_OR_NULL(di)) {
5453 ret = di ? PTR_ERR(di) : -ENOENT;
5454 goto out;
5455 }
5456
5457 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
5458 if (location->type != BTRFS_INODE_ITEM_KEY &&
5459 location->type != BTRFS_ROOT_ITEM_KEY) {
5460 ret = -EUCLEAN;
5461 btrfs_warn(root->fs_info,
5462 "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))",
5463 __func__, name, btrfs_ino(BTRFS_I(dir)),
5464 location->objectid, location->type, location->offset);
5465 }
5466 out:
5467 btrfs_free_path(path);
5468 return ret;
5469 }
5470
5471 /*
5472 * when we hit a tree root in a directory, the btrfs part of the inode
5473 * needs to be changed to reflect the root directory of the tree root. This
5474 * is kind of like crossing a mount point.
5475 */
5476 static int fixup_tree_root_location(struct btrfs_fs_info *fs_info,
5477 struct inode *dir,
5478 struct dentry *dentry,
5479 struct btrfs_key *location,
5480 struct btrfs_root **sub_root)
5481 {
5482 struct btrfs_path *path;
5483 struct btrfs_root *new_root;
5484 struct btrfs_root_ref *ref;
5485 struct extent_buffer *leaf;
5486 struct btrfs_key key;
5487 int ret;
5488 int err = 0;
5489
5490 path = btrfs_alloc_path();
5491 if (!path) {
5492 err = -ENOMEM;
5493 goto out;
5494 }
5495
5496 err = -ENOENT;
5497 key.objectid = BTRFS_I(dir)->root->root_key.objectid;
5498 key.type = BTRFS_ROOT_REF_KEY;
5499 key.offset = location->objectid;
5500
5501 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
5502 if (ret) {
5503 if (ret < 0)
5504 err = ret;
5505 goto out;
5506 }
5507
5508 leaf = path->nodes[0];
5509 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
5510 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(BTRFS_I(dir)) ||
5511 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
5512 goto out;
5513
5514 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
5515 (unsigned long)(ref + 1),
5516 dentry->d_name.len);
5517 if (ret)
5518 goto out;
5519
5520 btrfs_release_path(path);
5521
5522 new_root = btrfs_read_fs_root_no_name(fs_info, location);
5523 if (IS_ERR(new_root)) {
5524 err = PTR_ERR(new_root);
5525 goto out;
5526 }
5527
5528 *sub_root = new_root;
5529 location->objectid = btrfs_root_dirid(&new_root->root_item);
5530 location->type = BTRFS_INODE_ITEM_KEY;
5531 location->offset = 0;
5532 err = 0;
5533 out:
5534 btrfs_free_path(path);
5535 return err;
5536 }
5537
5538 static void inode_tree_add(struct inode *inode)
5539 {
5540 struct btrfs_root *root = BTRFS_I(inode)->root;
5541 struct btrfs_inode *entry;
5542 struct rb_node **p;
5543 struct rb_node *parent;
5544 struct rb_node *new = &BTRFS_I(inode)->rb_node;
5545 u64 ino = btrfs_ino(BTRFS_I(inode));
5546
5547 if (inode_unhashed(inode))
5548 return;
5549 parent = NULL;
5550 spin_lock(&root->inode_lock);
5551 p = &root->inode_tree.rb_node;
5552 while (*p) {
5553 parent = *p;
5554 entry = rb_entry(parent, struct btrfs_inode, rb_node);
5555
5556 if (ino < btrfs_ino(entry))
5557 p = &parent->rb_left;
5558 else if (ino > btrfs_ino(entry))
5559 p = &parent->rb_right;
5560 else {
5561 WARN_ON(!(entry->vfs_inode.i_state &
5562 (I_WILL_FREE | I_FREEING)));
5563 rb_replace_node(parent, new, &root->inode_tree);
5564 RB_CLEAR_NODE(parent);
5565 spin_unlock(&root->inode_lock);
5566 return;
5567 }
5568 }
5569 rb_link_node(new, parent, p);
5570 rb_insert_color(new, &root->inode_tree);
5571 spin_unlock(&root->inode_lock);
5572 }
5573
5574 static void inode_tree_del(struct inode *inode)
5575 {
5576 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5577 struct btrfs_root *root = BTRFS_I(inode)->root;
5578 int empty = 0;
5579
5580 spin_lock(&root->inode_lock);
5581 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
5582 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
5583 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
5584 empty = RB_EMPTY_ROOT(&root->inode_tree);
5585 }
5586 spin_unlock(&root->inode_lock);
5587
5588 if (empty && btrfs_root_refs(&root->root_item) == 0) {
5589 synchronize_srcu(&fs_info->subvol_srcu);
5590 spin_lock(&root->inode_lock);
5591 empty = RB_EMPTY_ROOT(&root->inode_tree);
5592 spin_unlock(&root->inode_lock);
5593 if (empty)
5594 btrfs_add_dead_root(root);
5595 }
5596 }
5597
5598
5599 static int btrfs_init_locked_inode(struct inode *inode, void *p)
5600 {
5601 struct btrfs_iget_args *args = p;
5602 inode->i_ino = args->location->objectid;
5603 memcpy(&BTRFS_I(inode)->location, args->location,
5604 sizeof(*args->location));
5605 BTRFS_I(inode)->root = args->root;
5606 return 0;
5607 }
5608
5609 static int btrfs_find_actor(struct inode *inode, void *opaque)
5610 {
5611 struct btrfs_iget_args *args = opaque;
5612 return args->location->objectid == BTRFS_I(inode)->location.objectid &&
5613 args->root == BTRFS_I(inode)->root;
5614 }
5615
5616 static struct inode *btrfs_iget_locked(struct super_block *s,
5617 struct btrfs_key *location,
5618 struct btrfs_root *root)
5619 {
5620 struct inode *inode;
5621 struct btrfs_iget_args args;
5622 unsigned long hashval = btrfs_inode_hash(location->objectid, root);
5623
5624 args.location = location;
5625 args.root = root;
5626
5627 inode = iget5_locked(s, hashval, btrfs_find_actor,
5628 btrfs_init_locked_inode,
5629 (void *)&args);
5630 return inode;
5631 }
5632
5633 /* Get an inode object given its location and corresponding root.
5634 * Returns in *is_new if the inode was read from disk
5635 */
5636 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
5637 struct btrfs_root *root, int *new)
5638 {
5639 struct inode *inode;
5640
5641 inode = btrfs_iget_locked(s, location, root);
5642 if (!inode)
5643 return ERR_PTR(-ENOMEM);
5644
5645 if (inode->i_state & I_NEW) {
5646 int ret;
5647
5648 ret = btrfs_read_locked_inode(inode);
5649 if (!ret) {
5650 inode_tree_add(inode);
5651 unlock_new_inode(inode);
5652 if (new)
5653 *new = 1;
5654 } else {
5655 iget_failed(inode);
5656 /*
5657 * ret > 0 can come from btrfs_search_slot called by
5658 * btrfs_read_locked_inode, this means the inode item
5659 * was not found.
5660 */
5661 if (ret > 0)
5662 ret = -ENOENT;
5663 inode = ERR_PTR(ret);
5664 }
5665 }
5666
5667 return inode;
5668 }
5669
5670 static struct inode *new_simple_dir(struct super_block *s,
5671 struct btrfs_key *key,
5672 struct btrfs_root *root)
5673 {
5674 struct inode *inode = new_inode(s);
5675
5676 if (!inode)
5677 return ERR_PTR(-ENOMEM);
5678
5679 BTRFS_I(inode)->root = root;
5680 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
5681 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
5682
5683 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
5684 inode->i_op = &btrfs_dir_ro_inode_operations;
5685 inode->i_opflags &= ~IOP_XATTR;
5686 inode->i_fop = &simple_dir_operations;
5687 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5688 inode->i_mtime = current_time(inode);
5689 inode->i_atime = inode->i_mtime;
5690 inode->i_ctime = inode->i_mtime;
5691 BTRFS_I(inode)->i_otime = inode->i_mtime;
5692
5693 return inode;
5694 }
5695
5696 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
5697 {
5698 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
5699 struct inode *inode;
5700 struct btrfs_root *root = BTRFS_I(dir)->root;
5701 struct btrfs_root *sub_root = root;
5702 struct btrfs_key location;
5703 int index;
5704 int ret = 0;
5705
5706 if (dentry->d_name.len > BTRFS_NAME_LEN)
5707 return ERR_PTR(-ENAMETOOLONG);
5708
5709 ret = btrfs_inode_by_name(dir, dentry, &location);
5710 if (ret < 0)
5711 return ERR_PTR(ret);
5712
5713 if (location.type == BTRFS_INODE_ITEM_KEY) {
5714 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
5715 return inode;
5716 }
5717
5718 index = srcu_read_lock(&fs_info->subvol_srcu);
5719 ret = fixup_tree_root_location(fs_info, dir, dentry,
5720 &location, &sub_root);
5721 if (ret < 0) {
5722 if (ret != -ENOENT)
5723 inode = ERR_PTR(ret);
5724 else
5725 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5726 } else {
5727 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
5728 }
5729 srcu_read_unlock(&fs_info->subvol_srcu, index);
5730
5731 if (!IS_ERR(inode) && root != sub_root) {
5732 down_read(&fs_info->cleanup_work_sem);
5733 if (!sb_rdonly(inode->i_sb))
5734 ret = btrfs_orphan_cleanup(sub_root);
5735 up_read(&fs_info->cleanup_work_sem);
5736 if (ret) {
5737 iput(inode);
5738 inode = ERR_PTR(ret);
5739 }
5740 }
5741
5742 return inode;
5743 }
5744
5745 static int btrfs_dentry_delete(const struct dentry *dentry)
5746 {
5747 struct btrfs_root *root;
5748 struct inode *inode = d_inode(dentry);
5749
5750 if (!inode && !IS_ROOT(dentry))
5751 inode = d_inode(dentry->d_parent);
5752
5753 if (inode) {
5754 root = BTRFS_I(inode)->root;
5755 if (btrfs_root_refs(&root->root_item) == 0)
5756 return 1;
5757
5758 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5759 return 1;
5760 }
5761 return 0;
5762 }
5763
5764 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5765 unsigned int flags)
5766 {
5767 struct inode *inode = btrfs_lookup_dentry(dir, dentry);
5768
5769 if (inode == ERR_PTR(-ENOENT))
5770 inode = NULL;
5771 return d_splice_alias(inode, dentry);
5772 }
5773
5774 unsigned char btrfs_filetype_table[] = {
5775 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5776 };
5777
5778 /*
5779 * All this infrastructure exists because dir_emit can fault, and we are holding
5780 * the tree lock when doing readdir. For now just allocate a buffer and copy
5781 * our information into that, and then dir_emit from the buffer. This is
5782 * similar to what NFS does, only we don't keep the buffer around in pagecache
5783 * because I'm afraid I'll mess that up. Long term we need to make filldir do
5784 * copy_to_user_inatomic so we don't have to worry about page faulting under the
5785 * tree lock.
5786 */
5787 static int btrfs_opendir(struct inode *inode, struct file *file)
5788 {
5789 struct btrfs_file_private *private;
5790
5791 private = kzalloc(sizeof(struct btrfs_file_private), GFP_KERNEL);
5792 if (!private)
5793 return -ENOMEM;
5794 private->filldir_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
5795 if (!private->filldir_buf) {
5796 kfree(private);
5797 return -ENOMEM;
5798 }
5799 file->private_data = private;
5800 return 0;
5801 }
5802
5803 struct dir_entry {
5804 u64 ino;
5805 u64 offset;
5806 unsigned type;
5807 int name_len;
5808 };
5809
5810 static int btrfs_filldir(void *addr, int entries, struct dir_context *ctx)
5811 {
5812 while (entries--) {
5813 struct dir_entry *entry = addr;
5814 char *name = (char *)(entry + 1);
5815
5816 ctx->pos = get_unaligned(&entry->offset);
5817 if (!dir_emit(ctx, name, get_unaligned(&entry->name_len),
5818 get_unaligned(&entry->ino),
5819 get_unaligned(&entry->type)))
5820 return 1;
5821 addr += sizeof(struct dir_entry) +
5822 get_unaligned(&entry->name_len);
5823 ctx->pos++;
5824 }
5825 return 0;
5826 }
5827
5828 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
5829 {
5830 struct inode *inode = file_inode(file);
5831 struct btrfs_root *root = BTRFS_I(inode)->root;
5832 struct btrfs_file_private *private = file->private_data;
5833 struct btrfs_dir_item *di;
5834 struct btrfs_key key;
5835 struct btrfs_key found_key;
5836 struct btrfs_path *path;
5837 void *addr;
5838 struct list_head ins_list;
5839 struct list_head del_list;
5840 int ret;
5841 struct extent_buffer *leaf;
5842 int slot;
5843 char *name_ptr;
5844 int name_len;
5845 int entries = 0;
5846 int total_len = 0;
5847 bool put = false;
5848 struct btrfs_key location;
5849
5850 if (!dir_emit_dots(file, ctx))
5851 return 0;
5852
5853 path = btrfs_alloc_path();
5854 if (!path)
5855 return -ENOMEM;
5856
5857 addr = private->filldir_buf;
5858 path->reada = READA_FORWARD;
5859
5860 INIT_LIST_HEAD(&ins_list);
5861 INIT_LIST_HEAD(&del_list);
5862 put = btrfs_readdir_get_delayed_items(inode, &ins_list, &del_list);
5863
5864 again:
5865 key.type = BTRFS_DIR_INDEX_KEY;
5866 key.offset = ctx->pos;
5867 key.objectid = btrfs_ino(BTRFS_I(inode));
5868
5869 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5870 if (ret < 0)
5871 goto err;
5872
5873 while (1) {
5874 struct dir_entry *entry;
5875
5876 leaf = path->nodes[0];
5877 slot = path->slots[0];
5878 if (slot >= btrfs_header_nritems(leaf)) {
5879 ret = btrfs_next_leaf(root, path);
5880 if (ret < 0)
5881 goto err;
5882 else if (ret > 0)
5883 break;
5884 continue;
5885 }
5886
5887 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5888
5889 if (found_key.objectid != key.objectid)
5890 break;
5891 if (found_key.type != BTRFS_DIR_INDEX_KEY)
5892 break;
5893 if (found_key.offset < ctx->pos)
5894 goto next;
5895 if (btrfs_should_delete_dir_index(&del_list, found_key.offset))
5896 goto next;
5897 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5898 name_len = btrfs_dir_name_len(leaf, di);
5899 if ((total_len + sizeof(struct dir_entry) + name_len) >=
5900 PAGE_SIZE) {
5901 btrfs_release_path(path);
5902 ret = btrfs_filldir(private->filldir_buf, entries, ctx);
5903 if (ret)
5904 goto nopos;
5905 addr = private->filldir_buf;
5906 entries = 0;
5907 total_len = 0;
5908 goto again;
5909 }
5910
5911 entry = addr;
5912 put_unaligned(name_len, &entry->name_len);
5913 name_ptr = (char *)(entry + 1);
5914 read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1),
5915 name_len);
5916 put_unaligned(btrfs_filetype_table[btrfs_dir_type(leaf, di)],
5917 &entry->type);
5918 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5919 put_unaligned(location.objectid, &entry->ino);
5920 put_unaligned(found_key.offset, &entry->offset);
5921 entries++;
5922 addr += sizeof(struct dir_entry) + name_len;
5923 total_len += sizeof(struct dir_entry) + name_len;
5924 next:
5925 path->slots[0]++;
5926 }
5927 btrfs_release_path(path);
5928
5929 ret = btrfs_filldir(private->filldir_buf, entries, ctx);
5930 if (ret)
5931 goto nopos;
5932
5933 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
5934 if (ret)
5935 goto nopos;
5936
5937 /*
5938 * Stop new entries from being returned after we return the last
5939 * entry.
5940 *
5941 * New directory entries are assigned a strictly increasing
5942 * offset. This means that new entries created during readdir
5943 * are *guaranteed* to be seen in the future by that readdir.
5944 * This has broken buggy programs which operate on names as
5945 * they're returned by readdir. Until we re-use freed offsets
5946 * we have this hack to stop new entries from being returned
5947 * under the assumption that they'll never reach this huge
5948 * offset.
5949 *
5950 * This is being careful not to overflow 32bit loff_t unless the
5951 * last entry requires it because doing so has broken 32bit apps
5952 * in the past.
5953 */
5954 if (ctx->pos >= INT_MAX)
5955 ctx->pos = LLONG_MAX;
5956 else
5957 ctx->pos = INT_MAX;
5958 nopos:
5959 ret = 0;
5960 err:
5961 if (put)
5962 btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list);
5963 btrfs_free_path(path);
5964 return ret;
5965 }
5966
5967 /*
5968 * This is somewhat expensive, updating the tree every time the
5969 * inode changes. But, it is most likely to find the inode in cache.
5970 * FIXME, needs more benchmarking...there are no reasons other than performance
5971 * to keep or drop this code.
5972 */
5973 static int btrfs_dirty_inode(struct inode *inode)
5974 {
5975 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5976 struct btrfs_root *root = BTRFS_I(inode)->root;
5977 struct btrfs_trans_handle *trans;
5978 int ret;
5979
5980 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5981 return 0;
5982
5983 trans = btrfs_join_transaction(root);
5984 if (IS_ERR(trans))
5985 return PTR_ERR(trans);
5986
5987 ret = btrfs_update_inode(trans, root, inode);
5988 if (ret && ret == -ENOSPC) {
5989 /* whoops, lets try again with the full transaction */
5990 btrfs_end_transaction(trans);
5991 trans = btrfs_start_transaction(root, 1);
5992 if (IS_ERR(trans))
5993 return PTR_ERR(trans);
5994
5995 ret = btrfs_update_inode(trans, root, inode);
5996 }
5997 btrfs_end_transaction(trans);
5998 if (BTRFS_I(inode)->delayed_node)
5999 btrfs_balance_delayed_items(fs_info);
6000
6001 return ret;
6002 }
6003
6004 /*
6005 * This is a copy of file_update_time. We need this so we can return error on
6006 * ENOSPC for updating the inode in the case of file write and mmap writes.
6007 */
6008 static int btrfs_update_time(struct inode *inode, struct timespec64 *now,
6009 int flags)
6010 {
6011 struct btrfs_root *root = BTRFS_I(inode)->root;
6012 bool dirty = flags & ~S_VERSION;
6013
6014 if (btrfs_root_readonly(root))
6015 return -EROFS;
6016
6017 if (flags & S_VERSION)
6018 dirty |= inode_maybe_inc_iversion(inode, dirty);
6019 if (flags & S_CTIME)
6020 inode->i_ctime = *now;
6021 if (flags & S_MTIME)
6022 inode->i_mtime = *now;
6023 if (flags & S_ATIME)
6024 inode->i_atime = *now;
6025 return dirty ? btrfs_dirty_inode(inode) : 0;
6026 }
6027
6028 /*
6029 * find the highest existing sequence number in a directory
6030 * and then set the in-memory index_cnt variable to reflect
6031 * free sequence numbers
6032 */
6033 static int btrfs_set_inode_index_count(struct btrfs_inode *inode)
6034 {
6035 struct btrfs_root *root = inode->root;
6036 struct btrfs_key key, found_key;
6037 struct btrfs_path *path;
6038 struct extent_buffer *leaf;
6039 int ret;
6040
6041 key.objectid = btrfs_ino(inode);
6042 key.type = BTRFS_DIR_INDEX_KEY;
6043 key.offset = (u64)-1;
6044
6045 path = btrfs_alloc_path();
6046 if (!path)
6047 return -ENOMEM;
6048
6049 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6050 if (ret < 0)
6051 goto out;
6052 /* FIXME: we should be able to handle this */
6053 if (ret == 0)
6054 goto out;
6055 ret = 0;
6056
6057 /*
6058 * MAGIC NUMBER EXPLANATION:
6059 * since we search a directory based on f_pos we have to start at 2
6060 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
6061 * else has to start at 2
6062 */
6063 if (path->slots[0] == 0) {
6064 inode->index_cnt = 2;
6065 goto out;
6066 }
6067
6068 path->slots[0]--;
6069
6070 leaf = path->nodes[0];
6071 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6072
6073 if (found_key.objectid != btrfs_ino(inode) ||
6074 found_key.type != BTRFS_DIR_INDEX_KEY) {
6075 inode->index_cnt = 2;
6076 goto out;
6077 }
6078
6079 inode->index_cnt = found_key.offset + 1;
6080 out:
6081 btrfs_free_path(path);
6082 return ret;
6083 }
6084
6085 /*
6086 * helper to find a free sequence number in a given directory. This current
6087 * code is very simple, later versions will do smarter things in the btree
6088 */
6089 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index)
6090 {
6091 int ret = 0;
6092
6093 if (dir->index_cnt == (u64)-1) {
6094 ret = btrfs_inode_delayed_dir_index_count(dir);
6095 if (ret) {
6096 ret = btrfs_set_inode_index_count(dir);
6097 if (ret)
6098 return ret;
6099 }
6100 }
6101
6102 *index = dir->index_cnt;
6103 dir->index_cnt++;
6104
6105 return ret;
6106 }
6107
6108 static int btrfs_insert_inode_locked(struct inode *inode)
6109 {
6110 struct btrfs_iget_args args;
6111 args.location = &BTRFS_I(inode)->location;
6112 args.root = BTRFS_I(inode)->root;
6113
6114 return insert_inode_locked4(inode,
6115 btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root),
6116 btrfs_find_actor, &args);
6117 }
6118
6119 /*
6120 * Inherit flags from the parent inode.
6121 *
6122 * Currently only the compression flags and the cow flags are inherited.
6123 */
6124 static void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
6125 {
6126 unsigned int flags;
6127
6128 if (!dir)
6129 return;
6130
6131 flags = BTRFS_I(dir)->flags;
6132
6133 if (flags & BTRFS_INODE_NOCOMPRESS) {
6134 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
6135 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
6136 } else if (flags & BTRFS_INODE_COMPRESS) {
6137 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
6138 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
6139 }
6140
6141 if (flags & BTRFS_INODE_NODATACOW) {
6142 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
6143 if (S_ISREG(inode->i_mode))
6144 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
6145 }
6146
6147 btrfs_sync_inode_flags_to_i_flags(inode);
6148 }
6149
6150 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
6151 struct btrfs_root *root,
6152 struct inode *dir,
6153 const char *name, int name_len,
6154 u64 ref_objectid, u64 objectid,
6155 umode_t mode, u64 *index)
6156 {
6157 struct btrfs_fs_info *fs_info = root->fs_info;
6158 struct inode *inode;
6159 struct btrfs_inode_item *inode_item;
6160 struct btrfs_key *location;
6161 struct btrfs_path *path;
6162 struct btrfs_inode_ref *ref;
6163 struct btrfs_key key[2];
6164 u32 sizes[2];
6165 int nitems = name ? 2 : 1;
6166 unsigned long ptr;
6167 int ret;
6168
6169 path = btrfs_alloc_path();
6170 if (!path)
6171 return ERR_PTR(-ENOMEM);
6172
6173 inode = new_inode(fs_info->sb);
6174 if (!inode) {
6175 btrfs_free_path(path);
6176 return ERR_PTR(-ENOMEM);
6177 }
6178
6179 /*
6180 * O_TMPFILE, set link count to 0, so that after this point,
6181 * we fill in an inode item with the correct link count.
6182 */
6183 if (!name)
6184 set_nlink(inode, 0);
6185
6186 /*
6187 * we have to initialize this early, so we can reclaim the inode
6188 * number if we fail afterwards in this function.
6189 */
6190 inode->i_ino = objectid;
6191
6192 if (dir && name) {
6193 trace_btrfs_inode_request(dir);
6194
6195 ret = btrfs_set_inode_index(BTRFS_I(dir), index);
6196 if (ret) {
6197 btrfs_free_path(path);
6198 iput(inode);
6199 return ERR_PTR(ret);
6200 }
6201 } else if (dir) {
6202 *index = 0;
6203 }
6204 /*
6205 * index_cnt is ignored for everything but a dir,
6206 * btrfs_set_inode_index_count has an explanation for the magic
6207 * number
6208 */
6209 BTRFS_I(inode)->index_cnt = 2;
6210 BTRFS_I(inode)->dir_index = *index;
6211 BTRFS_I(inode)->root = root;
6212 BTRFS_I(inode)->generation = trans->transid;
6213 inode->i_generation = BTRFS_I(inode)->generation;
6214
6215 /*
6216 * We could have gotten an inode number from somebody who was fsynced
6217 * and then removed in this same transaction, so let's just set full
6218 * sync since it will be a full sync anyway and this will blow away the
6219 * old info in the log.
6220 */
6221 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
6222
6223 key[0].objectid = objectid;
6224 key[0].type = BTRFS_INODE_ITEM_KEY;
6225 key[0].offset = 0;
6226
6227 sizes[0] = sizeof(struct btrfs_inode_item);
6228
6229 if (name) {
6230 /*
6231 * Start new inodes with an inode_ref. This is slightly more
6232 * efficient for small numbers of hard links since they will
6233 * be packed into one item. Extended refs will kick in if we
6234 * add more hard links than can fit in the ref item.
6235 */
6236 key[1].objectid = objectid;
6237 key[1].type = BTRFS_INODE_REF_KEY;
6238 key[1].offset = ref_objectid;
6239
6240 sizes[1] = name_len + sizeof(*ref);
6241 }
6242
6243 location = &BTRFS_I(inode)->location;
6244 location->objectid = objectid;
6245 location->offset = 0;
6246 location->type = BTRFS_INODE_ITEM_KEY;
6247
6248 ret = btrfs_insert_inode_locked(inode);
6249 if (ret < 0) {
6250 iput(inode);
6251 goto fail;
6252 }
6253
6254 path->leave_spinning = 1;
6255 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems);
6256 if (ret != 0)
6257 goto fail_unlock;
6258
6259 inode_init_owner(inode, dir, mode);
6260 inode_set_bytes(inode, 0);
6261
6262 inode->i_mtime = current_time(inode);
6263 inode->i_atime = inode->i_mtime;
6264 inode->i_ctime = inode->i_mtime;
6265 BTRFS_I(inode)->i_otime = inode->i_mtime;
6266
6267 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
6268 struct btrfs_inode_item);
6269 memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item,
6270 sizeof(*inode_item));
6271 fill_inode_item(trans, path->nodes[0], inode_item, inode);
6272
6273 if (name) {
6274 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
6275 struct btrfs_inode_ref);
6276 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
6277 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
6278 ptr = (unsigned long)(ref + 1);
6279 write_extent_buffer(path->nodes[0], name, ptr, name_len);
6280 }
6281
6282 btrfs_mark_buffer_dirty(path->nodes[0]);
6283 btrfs_free_path(path);
6284
6285 btrfs_inherit_iflags(inode, dir);
6286
6287 if (S_ISREG(mode)) {
6288 if (btrfs_test_opt(fs_info, NODATASUM))
6289 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
6290 if (btrfs_test_opt(fs_info, NODATACOW))
6291 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
6292 BTRFS_INODE_NODATASUM;
6293 }
6294
6295 inode_tree_add(inode);
6296
6297 trace_btrfs_inode_new(inode);
6298 btrfs_set_inode_last_trans(trans, inode);
6299
6300 btrfs_update_root_times(trans, root);
6301
6302 ret = btrfs_inode_inherit_props(trans, inode, dir);
6303 if (ret)
6304 btrfs_err(fs_info,
6305 "error inheriting props for ino %llu (root %llu): %d",
6306 btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret);
6307
6308 return inode;
6309
6310 fail_unlock:
6311 discard_new_inode(inode);
6312 fail:
6313 if (dir && name)
6314 BTRFS_I(dir)->index_cnt--;
6315 btrfs_free_path(path);
6316 return ERR_PTR(ret);
6317 }
6318
6319 static inline u8 btrfs_inode_type(struct inode *inode)
6320 {
6321 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
6322 }
6323
6324 /*
6325 * utility function to add 'inode' into 'parent_inode' with
6326 * a give name and a given sequence number.
6327 * if 'add_backref' is true, also insert a backref from the
6328 * inode to the parent directory.
6329 */
6330 int btrfs_add_link(struct btrfs_trans_handle *trans,
6331 struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
6332 const char *name, int name_len, int add_backref, u64 index)
6333 {
6334 int ret = 0;
6335 struct btrfs_key key;
6336 struct btrfs_root *root = parent_inode->root;
6337 u64 ino = btrfs_ino(inode);
6338 u64 parent_ino = btrfs_ino(parent_inode);
6339
6340 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6341 memcpy(&key, &inode->root->root_key, sizeof(key));
6342 } else {
6343 key.objectid = ino;
6344 key.type = BTRFS_INODE_ITEM_KEY;
6345 key.offset = 0;
6346 }
6347
6348 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6349 ret = btrfs_add_root_ref(trans, key.objectid,
6350 root->root_key.objectid, parent_ino,
6351 index, name, name_len);
6352 } else if (add_backref) {
6353 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
6354 parent_ino, index);
6355 }
6356
6357 /* Nothing to clean up yet */
6358 if (ret)
6359 return ret;
6360
6361 ret = btrfs_insert_dir_item(trans, name, name_len, parent_inode, &key,
6362 btrfs_inode_type(&inode->vfs_inode), index);
6363 if (ret == -EEXIST || ret == -EOVERFLOW)
6364 goto fail_dir_item;
6365 else if (ret) {
6366 btrfs_abort_transaction(trans, ret);
6367 return ret;
6368 }
6369
6370 btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size +
6371 name_len * 2);
6372 inode_inc_iversion(&parent_inode->vfs_inode);
6373 parent_inode->vfs_inode.i_mtime = parent_inode->vfs_inode.i_ctime =
6374 current_time(&parent_inode->vfs_inode);
6375 ret = btrfs_update_inode(trans, root, &parent_inode->vfs_inode);
6376 if (ret)
6377 btrfs_abort_transaction(trans, ret);
6378 return ret;
6379
6380 fail_dir_item:
6381 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6382 u64 local_index;
6383 int err;
6384 err = btrfs_del_root_ref(trans, key.objectid,
6385 root->root_key.objectid, parent_ino,
6386 &local_index, name, name_len);
6387
6388 } else if (add_backref) {
6389 u64 local_index;
6390 int err;
6391
6392 err = btrfs_del_inode_ref(trans, root, name, name_len,
6393 ino, parent_ino, &local_index);
6394 }
6395 return ret;
6396 }
6397
6398 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
6399 struct btrfs_inode *dir, struct dentry *dentry,
6400 struct btrfs_inode *inode, int backref, u64 index)
6401 {
6402 int err = btrfs_add_link(trans, dir, inode,
6403 dentry->d_name.name, dentry->d_name.len,
6404 backref, index);
6405 if (err > 0)
6406 err = -EEXIST;
6407 return err;
6408 }
6409
6410 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
6411 umode_t mode, dev_t rdev)
6412 {
6413 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6414 struct btrfs_trans_handle *trans;
6415 struct btrfs_root *root = BTRFS_I(dir)->root;
6416 struct inode *inode = NULL;
6417 int err;
6418 u64 objectid;
6419 u64 index = 0;
6420
6421 /*
6422 * 2 for inode item and ref
6423 * 2 for dir items
6424 * 1 for xattr if selinux is on
6425 */
6426 trans = btrfs_start_transaction(root, 5);
6427 if (IS_ERR(trans))
6428 return PTR_ERR(trans);
6429
6430 err = btrfs_find_free_ino(root, &objectid);
6431 if (err)
6432 goto out_unlock;
6433
6434 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6435 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6436 mode, &index);
6437 if (IS_ERR(inode)) {
6438 err = PTR_ERR(inode);
6439 inode = NULL;
6440 goto out_unlock;
6441 }
6442
6443 /*
6444 * If the active LSM wants to access the inode during
6445 * d_instantiate it needs these. Smack checks to see
6446 * if the filesystem supports xattrs by looking at the
6447 * ops vector.
6448 */
6449 inode->i_op = &btrfs_special_inode_operations;
6450 init_special_inode(inode, inode->i_mode, rdev);
6451
6452 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6453 if (err)
6454 goto out_unlock;
6455
6456 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6457 0, index);
6458 if (err)
6459 goto out_unlock;
6460
6461 btrfs_update_inode(trans, root, inode);
6462 d_instantiate_new(dentry, inode);
6463
6464 out_unlock:
6465 btrfs_end_transaction(trans);
6466 btrfs_btree_balance_dirty(fs_info);
6467 if (err && inode) {
6468 inode_dec_link_count(inode);
6469 discard_new_inode(inode);
6470 }
6471 return err;
6472 }
6473
6474 static int btrfs_create(struct inode *dir, struct dentry *dentry,
6475 umode_t mode, bool excl)
6476 {
6477 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6478 struct btrfs_trans_handle *trans;
6479 struct btrfs_root *root = BTRFS_I(dir)->root;
6480 struct inode *inode = NULL;
6481 int err;
6482 u64 objectid;
6483 u64 index = 0;
6484
6485 /*
6486 * 2 for inode item and ref
6487 * 2 for dir items
6488 * 1 for xattr if selinux is on
6489 */
6490 trans = btrfs_start_transaction(root, 5);
6491 if (IS_ERR(trans))
6492 return PTR_ERR(trans);
6493
6494 err = btrfs_find_free_ino(root, &objectid);
6495 if (err)
6496 goto out_unlock;
6497
6498 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6499 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6500 mode, &index);
6501 if (IS_ERR(inode)) {
6502 err = PTR_ERR(inode);
6503 inode = NULL;
6504 goto out_unlock;
6505 }
6506 /*
6507 * If the active LSM wants to access the inode during
6508 * d_instantiate it needs these. Smack checks to see
6509 * if the filesystem supports xattrs by looking at the
6510 * ops vector.
6511 */
6512 inode->i_fop = &btrfs_file_operations;
6513 inode->i_op = &btrfs_file_inode_operations;
6514 inode->i_mapping->a_ops = &btrfs_aops;
6515
6516 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6517 if (err)
6518 goto out_unlock;
6519
6520 err = btrfs_update_inode(trans, root, inode);
6521 if (err)
6522 goto out_unlock;
6523
6524 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6525 0, index);
6526 if (err)
6527 goto out_unlock;
6528
6529 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
6530 d_instantiate_new(dentry, inode);
6531
6532 out_unlock:
6533 btrfs_end_transaction(trans);
6534 if (err && inode) {
6535 inode_dec_link_count(inode);
6536 discard_new_inode(inode);
6537 }
6538 btrfs_btree_balance_dirty(fs_info);
6539 return err;
6540 }
6541
6542 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
6543 struct dentry *dentry)
6544 {
6545 struct btrfs_trans_handle *trans = NULL;
6546 struct btrfs_root *root = BTRFS_I(dir)->root;
6547 struct inode *inode = d_inode(old_dentry);
6548 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
6549 u64 index;
6550 int err;
6551 int drop_inode = 0;
6552
6553 /* do not allow sys_link's with other subvols of the same device */
6554 if (root->root_key.objectid != BTRFS_I(inode)->root->root_key.objectid)
6555 return -EXDEV;
6556
6557 if (inode->i_nlink >= BTRFS_LINK_MAX)
6558 return -EMLINK;
6559
6560 err = btrfs_set_inode_index(BTRFS_I(dir), &index);
6561 if (err)
6562 goto fail;
6563
6564 /*
6565 * 2 items for inode and inode ref
6566 * 2 items for dir items
6567 * 1 item for parent inode
6568 * 1 item for orphan item deletion if O_TMPFILE
6569 */
6570 trans = btrfs_start_transaction(root, inode->i_nlink ? 5 : 6);
6571 if (IS_ERR(trans)) {
6572 err = PTR_ERR(trans);
6573 trans = NULL;
6574 goto fail;
6575 }
6576
6577 /* There are several dir indexes for this inode, clear the cache. */
6578 BTRFS_I(inode)->dir_index = 0ULL;
6579 inc_nlink(inode);
6580 inode_inc_iversion(inode);
6581 inode->i_ctime = current_time(inode);
6582 ihold(inode);
6583 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
6584
6585 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6586 1, index);
6587
6588 if (err) {
6589 drop_inode = 1;
6590 } else {
6591 struct dentry *parent = dentry->d_parent;
6592 int ret;
6593
6594 err = btrfs_update_inode(trans, root, inode);
6595 if (err)
6596 goto fail;
6597 if (inode->i_nlink == 1) {
6598 /*
6599 * If new hard link count is 1, it's a file created
6600 * with open(2) O_TMPFILE flag.
6601 */
6602 err = btrfs_orphan_del(trans, BTRFS_I(inode));
6603 if (err)
6604 goto fail;
6605 }
6606 d_instantiate(dentry, inode);
6607 ret = btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent,
6608 true, NULL);
6609 if (ret == BTRFS_NEED_TRANS_COMMIT) {
6610 err = btrfs_commit_transaction(trans);
6611 trans = NULL;
6612 }
6613 }
6614
6615 fail:
6616 if (trans)
6617 btrfs_end_transaction(trans);
6618 if (drop_inode) {
6619 inode_dec_link_count(inode);
6620 iput(inode);
6621 }
6622 btrfs_btree_balance_dirty(fs_info);
6623 return err;
6624 }
6625
6626 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
6627 {
6628 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6629 struct inode *inode = NULL;
6630 struct btrfs_trans_handle *trans;
6631 struct btrfs_root *root = BTRFS_I(dir)->root;
6632 int err = 0;
6633 int drop_on_err = 0;
6634 u64 objectid = 0;
6635 u64 index = 0;
6636
6637 /*
6638 * 2 items for inode and ref
6639 * 2 items for dir items
6640 * 1 for xattr if selinux is on
6641 */
6642 trans = btrfs_start_transaction(root, 5);
6643 if (IS_ERR(trans))
6644 return PTR_ERR(trans);
6645
6646 err = btrfs_find_free_ino(root, &objectid);
6647 if (err)
6648 goto out_fail;
6649
6650 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6651 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6652 S_IFDIR | mode, &index);
6653 if (IS_ERR(inode)) {
6654 err = PTR_ERR(inode);
6655 inode = NULL;
6656 goto out_fail;
6657 }
6658
6659 drop_on_err = 1;
6660 /* these must be set before we unlock the inode */
6661 inode->i_op = &btrfs_dir_inode_operations;
6662 inode->i_fop = &btrfs_dir_file_operations;
6663
6664 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6665 if (err)
6666 goto out_fail;
6667
6668 btrfs_i_size_write(BTRFS_I(inode), 0);
6669 err = btrfs_update_inode(trans, root, inode);
6670 if (err)
6671 goto out_fail;
6672
6673 err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode),
6674 dentry->d_name.name,
6675 dentry->d_name.len, 0, index);
6676 if (err)
6677 goto out_fail;
6678
6679 d_instantiate_new(dentry, inode);
6680 drop_on_err = 0;
6681
6682 out_fail:
6683 btrfs_end_transaction(trans);
6684 if (err && inode) {
6685 inode_dec_link_count(inode);
6686 discard_new_inode(inode);
6687 }
6688 btrfs_btree_balance_dirty(fs_info);
6689 return err;
6690 }
6691
6692 static noinline int uncompress_inline(struct btrfs_path *path,
6693 struct page *page,
6694 size_t pg_offset, u64 extent_offset,
6695 struct btrfs_file_extent_item *item)
6696 {
6697 int ret;
6698 struct extent_buffer *leaf = path->nodes[0];
6699 char *tmp;
6700 size_t max_size;
6701 unsigned long inline_size;
6702 unsigned long ptr;
6703 int compress_type;
6704
6705 WARN_ON(pg_offset != 0);
6706 compress_type = btrfs_file_extent_compression(leaf, item);
6707 max_size = btrfs_file_extent_ram_bytes(leaf, item);
6708 inline_size = btrfs_file_extent_inline_item_len(leaf,
6709 btrfs_item_nr(path->slots[0]));
6710 tmp = kmalloc(inline_size, GFP_NOFS);
6711 if (!tmp)
6712 return -ENOMEM;
6713 ptr = btrfs_file_extent_inline_start(item);
6714
6715 read_extent_buffer(leaf, tmp, ptr, inline_size);
6716
6717 max_size = min_t(unsigned long, PAGE_SIZE, max_size);
6718 ret = btrfs_decompress(compress_type, tmp, page,
6719 extent_offset, inline_size, max_size);
6720
6721 /*
6722 * decompression code contains a memset to fill in any space between the end
6723 * of the uncompressed data and the end of max_size in case the decompressed
6724 * data ends up shorter than ram_bytes. That doesn't cover the hole between
6725 * the end of an inline extent and the beginning of the next block, so we
6726 * cover that region here.
6727 */
6728
6729 if (max_size + pg_offset < PAGE_SIZE) {
6730 char *map = kmap(page);
6731 memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset);
6732 kunmap(page);
6733 }
6734 kfree(tmp);
6735 return ret;
6736 }
6737
6738 /*
6739 * a bit scary, this does extent mapping from logical file offset to the disk.
6740 * the ugly parts come from merging extents from the disk with the in-ram
6741 * representation. This gets more complex because of the data=ordered code,
6742 * where the in-ram extents might be locked pending data=ordered completion.
6743 *
6744 * This also copies inline extents directly into the page.
6745 */
6746 struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
6747 struct page *page,
6748 size_t pg_offset, u64 start, u64 len,
6749 int create)
6750 {
6751 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6752 int ret;
6753 int err = 0;
6754 u64 extent_start = 0;
6755 u64 extent_end = 0;
6756 u64 objectid = btrfs_ino(inode);
6757 u32 found_type;
6758 struct btrfs_path *path = NULL;
6759 struct btrfs_root *root = inode->root;
6760 struct btrfs_file_extent_item *item;
6761 struct extent_buffer *leaf;
6762 struct btrfs_key found_key;
6763 struct extent_map *em = NULL;
6764 struct extent_map_tree *em_tree = &inode->extent_tree;
6765 struct extent_io_tree *io_tree = &inode->io_tree;
6766 const bool new_inline = !page || create;
6767
6768 read_lock(&em_tree->lock);
6769 em = lookup_extent_mapping(em_tree, start, len);
6770 if (em)
6771 em->bdev = fs_info->fs_devices->latest_bdev;
6772 read_unlock(&em_tree->lock);
6773
6774 if (em) {
6775 if (em->start > start || em->start + em->len <= start)
6776 free_extent_map(em);
6777 else if (em->block_start == EXTENT_MAP_INLINE && page)
6778 free_extent_map(em);
6779 else
6780 goto out;
6781 }
6782 em = alloc_extent_map();
6783 if (!em) {
6784 err = -ENOMEM;
6785 goto out;
6786 }
6787 em->bdev = fs_info->fs_devices->latest_bdev;
6788 em->start = EXTENT_MAP_HOLE;
6789 em->orig_start = EXTENT_MAP_HOLE;
6790 em->len = (u64)-1;
6791 em->block_len = (u64)-1;
6792
6793 path = btrfs_alloc_path();
6794 if (!path) {
6795 err = -ENOMEM;
6796 goto out;
6797 }
6798
6799 /* Chances are we'll be called again, so go ahead and do readahead */
6800 path->reada = READA_FORWARD;
6801
6802 /*
6803 * Unless we're going to uncompress the inline extent, no sleep would
6804 * happen.
6805 */
6806 path->leave_spinning = 1;
6807
6808 ret = btrfs_lookup_file_extent(NULL, root, path, objectid, start, 0);
6809 if (ret < 0) {
6810 err = ret;
6811 goto out;
6812 }
6813
6814 if (ret != 0) {
6815 if (path->slots[0] == 0)
6816 goto not_found;
6817 path->slots[0]--;
6818 }
6819
6820 leaf = path->nodes[0];
6821 item = btrfs_item_ptr(leaf, path->slots[0],
6822 struct btrfs_file_extent_item);
6823 /* are we inside the extent that was found? */
6824 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6825 found_type = found_key.type;
6826 if (found_key.objectid != objectid ||
6827 found_type != BTRFS_EXTENT_DATA_KEY) {
6828 /*
6829 * If we backup past the first extent we want to move forward
6830 * and see if there is an extent in front of us, otherwise we'll
6831 * say there is a hole for our whole search range which can
6832 * cause problems.
6833 */
6834 extent_end = start;
6835 goto next;
6836 }
6837
6838 found_type = btrfs_file_extent_type(leaf, item);
6839 extent_start = found_key.offset;
6840 if (found_type == BTRFS_FILE_EXTENT_REG ||
6841 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6842 extent_end = extent_start +
6843 btrfs_file_extent_num_bytes(leaf, item);
6844
6845 trace_btrfs_get_extent_show_fi_regular(inode, leaf, item,
6846 extent_start);
6847 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6848 size_t size;
6849
6850 size = btrfs_file_extent_ram_bytes(leaf, item);
6851 extent_end = ALIGN(extent_start + size,
6852 fs_info->sectorsize);
6853
6854 trace_btrfs_get_extent_show_fi_inline(inode, leaf, item,
6855 path->slots[0],
6856 extent_start);
6857 }
6858 next:
6859 if (start >= extent_end) {
6860 path->slots[0]++;
6861 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6862 ret = btrfs_next_leaf(root, path);
6863 if (ret < 0) {
6864 err = ret;
6865 goto out;
6866 }
6867 if (ret > 0)
6868 goto not_found;
6869 leaf = path->nodes[0];
6870 }
6871 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6872 if (found_key.objectid != objectid ||
6873 found_key.type != BTRFS_EXTENT_DATA_KEY)
6874 goto not_found;
6875 if (start + len <= found_key.offset)
6876 goto not_found;
6877 if (start > found_key.offset)
6878 goto next;
6879 em->start = start;
6880 em->orig_start = start;
6881 em->len = found_key.offset - start;
6882 goto not_found_em;
6883 }
6884
6885 btrfs_extent_item_to_extent_map(inode, path, item,
6886 new_inline, em);
6887
6888 if (found_type == BTRFS_FILE_EXTENT_REG ||
6889 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6890 goto insert;
6891 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6892 unsigned long ptr;
6893 char *map;
6894 size_t size;
6895 size_t extent_offset;
6896 size_t copy_size;
6897
6898 if (new_inline)
6899 goto out;
6900
6901 size = btrfs_file_extent_ram_bytes(leaf, item);
6902 extent_offset = page_offset(page) + pg_offset - extent_start;
6903 copy_size = min_t(u64, PAGE_SIZE - pg_offset,
6904 size - extent_offset);
6905 em->start = extent_start + extent_offset;
6906 em->len = ALIGN(copy_size, fs_info->sectorsize);
6907 em->orig_block_len = em->len;
6908 em->orig_start = em->start;
6909 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6910
6911 btrfs_set_path_blocking(path);
6912 if (!PageUptodate(page)) {
6913 if (btrfs_file_extent_compression(leaf, item) !=
6914 BTRFS_COMPRESS_NONE) {
6915 ret = uncompress_inline(path, page, pg_offset,
6916 extent_offset, item);
6917 if (ret) {
6918 err = ret;
6919 goto out;
6920 }
6921 } else {
6922 map = kmap(page);
6923 read_extent_buffer(leaf, map + pg_offset, ptr,
6924 copy_size);
6925 if (pg_offset + copy_size < PAGE_SIZE) {
6926 memset(map + pg_offset + copy_size, 0,
6927 PAGE_SIZE - pg_offset -
6928 copy_size);
6929 }
6930 kunmap(page);
6931 }
6932 flush_dcache_page(page);
6933 }
6934 set_extent_uptodate(io_tree, em->start,
6935 extent_map_end(em) - 1, NULL, GFP_NOFS);
6936 goto insert;
6937 }
6938 not_found:
6939 em->start = start;
6940 em->orig_start = start;
6941 em->len = len;
6942 not_found_em:
6943 em->block_start = EXTENT_MAP_HOLE;
6944 insert:
6945 btrfs_release_path(path);
6946 if (em->start > start || extent_map_end(em) <= start) {
6947 btrfs_err(fs_info,
6948 "bad extent! em: [%llu %llu] passed [%llu %llu]",
6949 em->start, em->len, start, len);
6950 err = -EIO;
6951 goto out;
6952 }
6953
6954 err = 0;
6955 write_lock(&em_tree->lock);
6956 err = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
6957 write_unlock(&em_tree->lock);
6958 out:
6959 btrfs_free_path(path);
6960
6961 trace_btrfs_get_extent(root, inode, em);
6962
6963 if (err) {
6964 free_extent_map(em);
6965 return ERR_PTR(err);
6966 }
6967 BUG_ON(!em); /* Error is always set */
6968 return em;
6969 }
6970
6971 struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode,
6972 struct page *page,
6973 size_t pg_offset, u64 start, u64 len,
6974 int create)
6975 {
6976 struct extent_map *em;
6977 struct extent_map *hole_em = NULL;
6978 u64 range_start = start;
6979 u64 end;
6980 u64 found;
6981 u64 found_end;
6982 int err = 0;
6983
6984 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
6985 if (IS_ERR(em))
6986 return em;
6987 /*
6988 * If our em maps to:
6989 * - a hole or
6990 * - a pre-alloc extent,
6991 * there might actually be delalloc bytes behind it.
6992 */
6993 if (em->block_start != EXTENT_MAP_HOLE &&
6994 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6995 return em;
6996 else
6997 hole_em = em;
6998
6999 /* check to see if we've wrapped (len == -1 or similar) */
7000 end = start + len;
7001 if (end < start)
7002 end = (u64)-1;
7003 else
7004 end -= 1;
7005
7006 em = NULL;
7007
7008 /* ok, we didn't find anything, lets look for delalloc */
7009 found = count_range_bits(&inode->io_tree, &range_start,
7010 end, len, EXTENT_DELALLOC, 1);
7011 found_end = range_start + found;
7012 if (found_end < range_start)
7013 found_end = (u64)-1;
7014
7015 /*
7016 * we didn't find anything useful, return
7017 * the original results from get_extent()
7018 */
7019 if (range_start > end || found_end <= start) {
7020 em = hole_em;
7021 hole_em = NULL;
7022 goto out;
7023 }
7024
7025 /* adjust the range_start to make sure it doesn't
7026 * go backwards from the start they passed in
7027 */
7028 range_start = max(start, range_start);
7029 found = found_end - range_start;
7030
7031 if (found > 0) {
7032 u64 hole_start = start;
7033 u64 hole_len = len;
7034
7035 em = alloc_extent_map();
7036 if (!em) {
7037 err = -ENOMEM;
7038 goto out;
7039 }
7040 /*
7041 * when btrfs_get_extent can't find anything it
7042 * returns one huge hole
7043 *
7044 * make sure what it found really fits our range, and
7045 * adjust to make sure it is based on the start from
7046 * the caller
7047 */
7048 if (hole_em) {
7049 u64 calc_end = extent_map_end(hole_em);
7050
7051 if (calc_end <= start || (hole_em->start > end)) {
7052 free_extent_map(hole_em);
7053 hole_em = NULL;
7054 } else {
7055 hole_start = max(hole_em->start, start);
7056 hole_len = calc_end - hole_start;
7057 }
7058 }
7059 em->bdev = NULL;
7060 if (hole_em && range_start > hole_start) {
7061 /* our hole starts before our delalloc, so we
7062 * have to return just the parts of the hole
7063 * that go until the delalloc starts
7064 */
7065 em->len = min(hole_len,
7066 range_start - hole_start);
7067 em->start = hole_start;
7068 em->orig_start = hole_start;
7069 /*
7070 * don't adjust block start at all,
7071 * it is fixed at EXTENT_MAP_HOLE
7072 */
7073 em->block_start = hole_em->block_start;
7074 em->block_len = hole_len;
7075 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
7076 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
7077 } else {
7078 em->start = range_start;
7079 em->len = found;
7080 em->orig_start = range_start;
7081 em->block_start = EXTENT_MAP_DELALLOC;
7082 em->block_len = found;
7083 }
7084 } else {
7085 return hole_em;
7086 }
7087 out:
7088
7089 free_extent_map(hole_em);
7090 if (err) {
7091 free_extent_map(em);
7092 return ERR_PTR(err);
7093 }
7094 return em;
7095 }
7096
7097 static struct extent_map *btrfs_create_dio_extent(struct inode *inode,
7098 const u64 start,
7099 const u64 len,
7100 const u64 orig_start,
7101 const u64 block_start,
7102 const u64 block_len,
7103 const u64 orig_block_len,
7104 const u64 ram_bytes,
7105 const int type)
7106 {
7107 struct extent_map *em = NULL;
7108 int ret;
7109
7110 if (type != BTRFS_ORDERED_NOCOW) {
7111 em = create_io_em(inode, start, len, orig_start,
7112 block_start, block_len, orig_block_len,
7113 ram_bytes,
7114 BTRFS_COMPRESS_NONE, /* compress_type */
7115 type);
7116 if (IS_ERR(em))
7117 goto out;
7118 }
7119 ret = btrfs_add_ordered_extent_dio(inode, start, block_start,
7120 len, block_len, type);
7121 if (ret) {
7122 if (em) {
7123 free_extent_map(em);
7124 btrfs_drop_extent_cache(BTRFS_I(inode), start,
7125 start + len - 1, 0);
7126 }
7127 em = ERR_PTR(ret);
7128 }
7129 out:
7130
7131 return em;
7132 }
7133
7134 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
7135 u64 start, u64 len)
7136 {
7137 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7138 struct btrfs_root *root = BTRFS_I(inode)->root;
7139 struct extent_map *em;
7140 struct btrfs_key ins;
7141 u64 alloc_hint;
7142 int ret;
7143
7144 alloc_hint = get_extent_allocation_hint(inode, start, len);
7145 ret = btrfs_reserve_extent(root, len, len, fs_info->sectorsize,
7146 0, alloc_hint, &ins, 1, 1);
7147 if (ret)
7148 return ERR_PTR(ret);
7149
7150 em = btrfs_create_dio_extent(inode, start, ins.offset, start,
7151 ins.objectid, ins.offset, ins.offset,
7152 ins.offset, BTRFS_ORDERED_REGULAR);
7153 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
7154 if (IS_ERR(em))
7155 btrfs_free_reserved_extent(fs_info, ins.objectid,
7156 ins.offset, 1);
7157
7158 return em;
7159 }
7160
7161 /*
7162 * returns 1 when the nocow is safe, < 1 on error, 0 if the
7163 * block must be cow'd
7164 */
7165 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
7166 u64 *orig_start, u64 *orig_block_len,
7167 u64 *ram_bytes)
7168 {
7169 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7170 struct btrfs_path *path;
7171 int ret;
7172 struct extent_buffer *leaf;
7173 struct btrfs_root *root = BTRFS_I(inode)->root;
7174 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7175 struct btrfs_file_extent_item *fi;
7176 struct btrfs_key key;
7177 u64 disk_bytenr;
7178 u64 backref_offset;
7179 u64 extent_end;
7180 u64 num_bytes;
7181 int slot;
7182 int found_type;
7183 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
7184
7185 path = btrfs_alloc_path();
7186 if (!path)
7187 return -ENOMEM;
7188
7189 ret = btrfs_lookup_file_extent(NULL, root, path,
7190 btrfs_ino(BTRFS_I(inode)), offset, 0);
7191 if (ret < 0)
7192 goto out;
7193
7194 slot = path->slots[0];
7195 if (ret == 1) {
7196 if (slot == 0) {
7197 /* can't find the item, must cow */
7198 ret = 0;
7199 goto out;
7200 }
7201 slot--;
7202 }
7203 ret = 0;
7204 leaf = path->nodes[0];
7205 btrfs_item_key_to_cpu(leaf, &key, slot);
7206 if (key.objectid != btrfs_ino(BTRFS_I(inode)) ||
7207 key.type != BTRFS_EXTENT_DATA_KEY) {
7208 /* not our file or wrong item type, must cow */
7209 goto out;
7210 }
7211
7212 if (key.offset > offset) {
7213 /* Wrong offset, must cow */
7214 goto out;
7215 }
7216
7217 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
7218 found_type = btrfs_file_extent_type(leaf, fi);
7219 if (found_type != BTRFS_FILE_EXTENT_REG &&
7220 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
7221 /* not a regular extent, must cow */
7222 goto out;
7223 }
7224
7225 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
7226 goto out;
7227
7228 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
7229 if (extent_end <= offset)
7230 goto out;
7231
7232 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7233 if (disk_bytenr == 0)
7234 goto out;
7235
7236 if (btrfs_file_extent_compression(leaf, fi) ||
7237 btrfs_file_extent_encryption(leaf, fi) ||
7238 btrfs_file_extent_other_encoding(leaf, fi))
7239 goto out;
7240
7241 /*
7242 * Do the same check as in btrfs_cross_ref_exist but without the
7243 * unnecessary search.
7244 */
7245 if (btrfs_file_extent_generation(leaf, fi) <=
7246 btrfs_root_last_snapshot(&root->root_item))
7247 goto out;
7248
7249 backref_offset = btrfs_file_extent_offset(leaf, fi);
7250
7251 if (orig_start) {
7252 *orig_start = key.offset - backref_offset;
7253 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
7254 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
7255 }
7256
7257 if (btrfs_extent_readonly(fs_info, disk_bytenr))
7258 goto out;
7259
7260 num_bytes = min(offset + *len, extent_end) - offset;
7261 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) {
7262 u64 range_end;
7263
7264 range_end = round_up(offset + num_bytes,
7265 root->fs_info->sectorsize) - 1;
7266 ret = test_range_bit(io_tree, offset, range_end,
7267 EXTENT_DELALLOC, 0, NULL);
7268 if (ret) {
7269 ret = -EAGAIN;
7270 goto out;
7271 }
7272 }
7273
7274 btrfs_release_path(path);
7275
7276 /*
7277 * look for other files referencing this extent, if we
7278 * find any we must cow
7279 */
7280
7281 ret = btrfs_cross_ref_exist(root, btrfs_ino(BTRFS_I(inode)),
7282 key.offset - backref_offset, disk_bytenr);
7283 if (ret) {
7284 ret = 0;
7285 goto out;
7286 }
7287
7288 /*
7289 * adjust disk_bytenr and num_bytes to cover just the bytes
7290 * in this extent we are about to write. If there
7291 * are any csums in that range we have to cow in order
7292 * to keep the csums correct
7293 */
7294 disk_bytenr += backref_offset;
7295 disk_bytenr += offset - key.offset;
7296 if (csum_exist_in_range(fs_info, disk_bytenr, num_bytes))
7297 goto out;
7298 /*
7299 * all of the above have passed, it is safe to overwrite this extent
7300 * without cow
7301 */
7302 *len = num_bytes;
7303 ret = 1;
7304 out:
7305 btrfs_free_path(path);
7306 return ret;
7307 }
7308
7309 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
7310 struct extent_state **cached_state, int writing)
7311 {
7312 struct btrfs_ordered_extent *ordered;
7313 int ret = 0;
7314
7315 while (1) {
7316 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7317 cached_state);
7318 /*
7319 * We're concerned with the entire range that we're going to be
7320 * doing DIO to, so we need to make sure there's no ordered
7321 * extents in this range.
7322 */
7323 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), lockstart,
7324 lockend - lockstart + 1);
7325
7326 /*
7327 * We need to make sure there are no buffered pages in this
7328 * range either, we could have raced between the invalidate in
7329 * generic_file_direct_write and locking the extent. The
7330 * invalidate needs to happen so that reads after a write do not
7331 * get stale data.
7332 */
7333 if (!ordered &&
7334 (!writing || !filemap_range_has_page(inode->i_mapping,
7335 lockstart, lockend)))
7336 break;
7337
7338 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7339 cached_state);
7340
7341 if (ordered) {
7342 /*
7343 * If we are doing a DIO read and the ordered extent we
7344 * found is for a buffered write, we can not wait for it
7345 * to complete and retry, because if we do so we can
7346 * deadlock with concurrent buffered writes on page
7347 * locks. This happens only if our DIO read covers more
7348 * than one extent map, if at this point has already
7349 * created an ordered extent for a previous extent map
7350 * and locked its range in the inode's io tree, and a
7351 * concurrent write against that previous extent map's
7352 * range and this range started (we unlock the ranges
7353 * in the io tree only when the bios complete and
7354 * buffered writes always lock pages before attempting
7355 * to lock range in the io tree).
7356 */
7357 if (writing ||
7358 test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags))
7359 btrfs_start_ordered_extent(inode, ordered, 1);
7360 else
7361 ret = -ENOTBLK;
7362 btrfs_put_ordered_extent(ordered);
7363 } else {
7364 /*
7365 * We could trigger writeback for this range (and wait
7366 * for it to complete) and then invalidate the pages for
7367 * this range (through invalidate_inode_pages2_range()),
7368 * but that can lead us to a deadlock with a concurrent
7369 * call to readpages() (a buffered read or a defrag call
7370 * triggered a readahead) on a page lock due to an
7371 * ordered dio extent we created before but did not have
7372 * yet a corresponding bio submitted (whence it can not
7373 * complete), which makes readpages() wait for that
7374 * ordered extent to complete while holding a lock on
7375 * that page.
7376 */
7377 ret = -ENOTBLK;
7378 }
7379
7380 if (ret)
7381 break;
7382
7383 cond_resched();
7384 }
7385
7386 return ret;
7387 }
7388
7389 /* The callers of this must take lock_extent() */
7390 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
7391 u64 orig_start, u64 block_start,
7392 u64 block_len, u64 orig_block_len,
7393 u64 ram_bytes, int compress_type,
7394 int type)
7395 {
7396 struct extent_map_tree *em_tree;
7397 struct extent_map *em;
7398 struct btrfs_root *root = BTRFS_I(inode)->root;
7399 int ret;
7400
7401 ASSERT(type == BTRFS_ORDERED_PREALLOC ||
7402 type == BTRFS_ORDERED_COMPRESSED ||
7403 type == BTRFS_ORDERED_NOCOW ||
7404 type == BTRFS_ORDERED_REGULAR);
7405
7406 em_tree = &BTRFS_I(inode)->extent_tree;
7407 em = alloc_extent_map();
7408 if (!em)
7409 return ERR_PTR(-ENOMEM);
7410
7411 em->start = start;
7412 em->orig_start = orig_start;
7413 em->len = len;
7414 em->block_len = block_len;
7415 em->block_start = block_start;
7416 em->bdev = root->fs_info->fs_devices->latest_bdev;
7417 em->orig_block_len = orig_block_len;
7418 em->ram_bytes = ram_bytes;
7419 em->generation = -1;
7420 set_bit(EXTENT_FLAG_PINNED, &em->flags);
7421 if (type == BTRFS_ORDERED_PREALLOC) {
7422 set_bit(EXTENT_FLAG_FILLING, &em->flags);
7423 } else if (type == BTRFS_ORDERED_COMPRESSED) {
7424 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
7425 em->compress_type = compress_type;
7426 }
7427
7428 do {
7429 btrfs_drop_extent_cache(BTRFS_I(inode), em->start,
7430 em->start + em->len - 1, 0);
7431 write_lock(&em_tree->lock);
7432 ret = add_extent_mapping(em_tree, em, 1);
7433 write_unlock(&em_tree->lock);
7434 /*
7435 * The caller has taken lock_extent(), who could race with us
7436 * to add em?
7437 */
7438 } while (ret == -EEXIST);
7439
7440 if (ret) {
7441 free_extent_map(em);
7442 return ERR_PTR(ret);
7443 }
7444
7445 /* em got 2 refs now, callers needs to do free_extent_map once. */
7446 return em;
7447 }
7448
7449
7450 static int btrfs_get_blocks_direct_read(struct extent_map *em,
7451 struct buffer_head *bh_result,
7452 struct inode *inode,
7453 u64 start, u64 len)
7454 {
7455 if (em->block_start == EXTENT_MAP_HOLE ||
7456 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7457 return -ENOENT;
7458
7459 len = min(len, em->len - (start - em->start));
7460
7461 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
7462 inode->i_blkbits;
7463 bh_result->b_size = len;
7464 bh_result->b_bdev = em->bdev;
7465 set_buffer_mapped(bh_result);
7466
7467 return 0;
7468 }
7469
7470 static int btrfs_get_blocks_direct_write(struct extent_map **map,
7471 struct buffer_head *bh_result,
7472 struct inode *inode,
7473 struct btrfs_dio_data *dio_data,
7474 u64 start, u64 len)
7475 {
7476 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7477 struct extent_map *em = *map;
7478 int ret = 0;
7479
7480 /*
7481 * We don't allocate a new extent in the following cases
7482 *
7483 * 1) The inode is marked as NODATACOW. In this case we'll just use the
7484 * existing extent.
7485 * 2) The extent is marked as PREALLOC. We're good to go here and can
7486 * just use the extent.
7487 *
7488 */
7489 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
7490 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
7491 em->block_start != EXTENT_MAP_HOLE)) {
7492 int type;
7493 u64 block_start, orig_start, orig_block_len, ram_bytes;
7494
7495 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7496 type = BTRFS_ORDERED_PREALLOC;
7497 else
7498 type = BTRFS_ORDERED_NOCOW;
7499 len = min(len, em->len - (start - em->start));
7500 block_start = em->block_start + (start - em->start);
7501
7502 if (can_nocow_extent(inode, start, &len, &orig_start,
7503 &orig_block_len, &ram_bytes) == 1 &&
7504 btrfs_inc_nocow_writers(fs_info, block_start)) {
7505 struct extent_map *em2;
7506
7507 em2 = btrfs_create_dio_extent(inode, start, len,
7508 orig_start, block_start,
7509 len, orig_block_len,
7510 ram_bytes, type);
7511 btrfs_dec_nocow_writers(fs_info, block_start);
7512 if (type == BTRFS_ORDERED_PREALLOC) {
7513 free_extent_map(em);
7514 *map = em = em2;
7515 }
7516
7517 if (em2 && IS_ERR(em2)) {
7518 ret = PTR_ERR(em2);
7519 goto out;
7520 }
7521 /*
7522 * For inode marked NODATACOW or extent marked PREALLOC,
7523 * use the existing or preallocated extent, so does not
7524 * need to adjust btrfs_space_info's bytes_may_use.
7525 */
7526 btrfs_free_reserved_data_space_noquota(inode, start,
7527 len);
7528 goto skip_cow;
7529 }
7530 }
7531
7532 /* this will cow the extent */
7533 len = bh_result->b_size;
7534 free_extent_map(em);
7535 *map = em = btrfs_new_extent_direct(inode, start, len);
7536 if (IS_ERR(em)) {
7537 ret = PTR_ERR(em);
7538 goto out;
7539 }
7540
7541 len = min(len, em->len - (start - em->start));
7542
7543 skip_cow:
7544 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
7545 inode->i_blkbits;
7546 bh_result->b_size = len;
7547 bh_result->b_bdev = em->bdev;
7548 set_buffer_mapped(bh_result);
7549
7550 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7551 set_buffer_new(bh_result);
7552
7553 /*
7554 * Need to update the i_size under the extent lock so buffered
7555 * readers will get the updated i_size when we unlock.
7556 */
7557 if (!dio_data->overwrite && start + len > i_size_read(inode))
7558 i_size_write(inode, start + len);
7559
7560 WARN_ON(dio_data->reserve < len);
7561 dio_data->reserve -= len;
7562 dio_data->unsubmitted_oe_range_end = start + len;
7563 current->journal_info = dio_data;
7564 out:
7565 return ret;
7566 }
7567
7568 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
7569 struct buffer_head *bh_result, int create)
7570 {
7571 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7572 struct extent_map *em;
7573 struct extent_state *cached_state = NULL;
7574 struct btrfs_dio_data *dio_data = NULL;
7575 u64 start = iblock << inode->i_blkbits;
7576 u64 lockstart, lockend;
7577 u64 len = bh_result->b_size;
7578 int unlock_bits = EXTENT_LOCKED;
7579 int ret = 0;
7580
7581 if (create)
7582 unlock_bits |= EXTENT_DIRTY;
7583 else
7584 len = min_t(u64, len, fs_info->sectorsize);
7585
7586 lockstart = start;
7587 lockend = start + len - 1;
7588
7589 if (current->journal_info) {
7590 /*
7591 * Need to pull our outstanding extents and set journal_info to NULL so
7592 * that anything that needs to check if there's a transaction doesn't get
7593 * confused.
7594 */
7595 dio_data = current->journal_info;
7596 current->journal_info = NULL;
7597 }
7598
7599 /*
7600 * If this errors out it's because we couldn't invalidate pagecache for
7601 * this range and we need to fallback to buffered.
7602 */
7603 if (lock_extent_direct(inode, lockstart, lockend, &cached_state,
7604 create)) {
7605 ret = -ENOTBLK;
7606 goto err;
7607 }
7608
7609 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
7610 if (IS_ERR(em)) {
7611 ret = PTR_ERR(em);
7612 goto unlock_err;
7613 }
7614
7615 /*
7616 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
7617 * io. INLINE is special, and we could probably kludge it in here, but
7618 * it's still buffered so for safety lets just fall back to the generic
7619 * buffered path.
7620 *
7621 * For COMPRESSED we _have_ to read the entire extent in so we can
7622 * decompress it, so there will be buffering required no matter what we
7623 * do, so go ahead and fallback to buffered.
7624 *
7625 * We return -ENOTBLK because that's what makes DIO go ahead and go back
7626 * to buffered IO. Don't blame me, this is the price we pay for using
7627 * the generic code.
7628 */
7629 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
7630 em->block_start == EXTENT_MAP_INLINE) {
7631 free_extent_map(em);
7632 ret = -ENOTBLK;
7633 goto unlock_err;
7634 }
7635
7636 if (create) {
7637 ret = btrfs_get_blocks_direct_write(&em, bh_result, inode,
7638 dio_data, start, len);
7639 if (ret < 0)
7640 goto unlock_err;
7641
7642 /* clear and unlock the entire range */
7643 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7644 unlock_bits, 1, 0, &cached_state);
7645 } else {
7646 ret = btrfs_get_blocks_direct_read(em, bh_result, inode,
7647 start, len);
7648 /* Can be negative only if we read from a hole */
7649 if (ret < 0) {
7650 ret = 0;
7651 free_extent_map(em);
7652 goto unlock_err;
7653 }
7654 /*
7655 * We need to unlock only the end area that we aren't using.
7656 * The rest is going to be unlocked by the endio routine.
7657 */
7658 lockstart = start + bh_result->b_size;
7659 if (lockstart < lockend) {
7660 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
7661 lockend, unlock_bits, 1, 0,
7662 &cached_state);
7663 } else {
7664 free_extent_state(cached_state);
7665 }
7666 }
7667
7668 free_extent_map(em);
7669
7670 return 0;
7671
7672 unlock_err:
7673 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7674 unlock_bits, 1, 0, &cached_state);
7675 err:
7676 if (dio_data)
7677 current->journal_info = dio_data;
7678 return ret;
7679 }
7680
7681 static inline blk_status_t submit_dio_repair_bio(struct inode *inode,
7682 struct bio *bio,
7683 int mirror_num)
7684 {
7685 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7686 blk_status_t ret;
7687
7688 BUG_ON(bio_op(bio) == REQ_OP_WRITE);
7689
7690 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DIO_REPAIR);
7691 if (ret)
7692 return ret;
7693
7694 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
7695
7696 return ret;
7697 }
7698
7699 static int btrfs_check_dio_repairable(struct inode *inode,
7700 struct bio *failed_bio,
7701 struct io_failure_record *failrec,
7702 int failed_mirror)
7703 {
7704 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7705 int num_copies;
7706
7707 num_copies = btrfs_num_copies(fs_info, failrec->logical, failrec->len);
7708 if (num_copies == 1) {
7709 /*
7710 * we only have a single copy of the data, so don't bother with
7711 * all the retry and error correction code that follows. no
7712 * matter what the error is, it is very likely to persist.
7713 */
7714 btrfs_debug(fs_info,
7715 "Check DIO Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d",
7716 num_copies, failrec->this_mirror, failed_mirror);
7717 return 0;
7718 }
7719
7720 failrec->failed_mirror = failed_mirror;
7721 failrec->this_mirror++;
7722 if (failrec->this_mirror == failed_mirror)
7723 failrec->this_mirror++;
7724
7725 if (failrec->this_mirror > num_copies) {
7726 btrfs_debug(fs_info,
7727 "Check DIO Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d",
7728 num_copies, failrec->this_mirror, failed_mirror);
7729 return 0;
7730 }
7731
7732 return 1;
7733 }
7734
7735 static blk_status_t dio_read_error(struct inode *inode, struct bio *failed_bio,
7736 struct page *page, unsigned int pgoff,
7737 u64 start, u64 end, int failed_mirror,
7738 bio_end_io_t *repair_endio, void *repair_arg)
7739 {
7740 struct io_failure_record *failrec;
7741 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7742 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
7743 struct bio *bio;
7744 int isector;
7745 unsigned int read_mode = 0;
7746 int segs;
7747 int ret;
7748 blk_status_t status;
7749 struct bio_vec bvec;
7750
7751 BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE);
7752
7753 ret = btrfs_get_io_failure_record(inode, start, end, &failrec);
7754 if (ret)
7755 return errno_to_blk_status(ret);
7756
7757 ret = btrfs_check_dio_repairable(inode, failed_bio, failrec,
7758 failed_mirror);
7759 if (!ret) {
7760 free_io_failure(failure_tree, io_tree, failrec);
7761 return BLK_STS_IOERR;
7762 }
7763
7764 segs = bio_segments(failed_bio);
7765 bio_get_first_bvec(failed_bio, &bvec);
7766 if (segs > 1 ||
7767 (bvec.bv_len > btrfs_inode_sectorsize(inode)))
7768 read_mode |= REQ_FAILFAST_DEV;
7769
7770 isector = start - btrfs_io_bio(failed_bio)->logical;
7771 isector >>= inode->i_sb->s_blocksize_bits;
7772 bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page,
7773 pgoff, isector, repair_endio, repair_arg);
7774 bio->bi_opf = REQ_OP_READ | read_mode;
7775
7776 btrfs_debug(BTRFS_I(inode)->root->fs_info,
7777 "repair DIO read error: submitting new dio read[%#x] to this_mirror=%d, in_validation=%d",
7778 read_mode, failrec->this_mirror, failrec->in_validation);
7779
7780 status = submit_dio_repair_bio(inode, bio, failrec->this_mirror);
7781 if (status) {
7782 free_io_failure(failure_tree, io_tree, failrec);
7783 bio_put(bio);
7784 }
7785
7786 return status;
7787 }
7788
7789 struct btrfs_retry_complete {
7790 struct completion done;
7791 struct inode *inode;
7792 u64 start;
7793 int uptodate;
7794 };
7795
7796 static void btrfs_retry_endio_nocsum(struct bio *bio)
7797 {
7798 struct btrfs_retry_complete *done = bio->bi_private;
7799 struct inode *inode = done->inode;
7800 struct bio_vec *bvec;
7801 struct extent_io_tree *io_tree, *failure_tree;
7802 int i;
7803
7804 if (bio->bi_status)
7805 goto end;
7806
7807 ASSERT(bio->bi_vcnt == 1);
7808 io_tree = &BTRFS_I(inode)->io_tree;
7809 failure_tree = &BTRFS_I(inode)->io_failure_tree;
7810 ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(inode));
7811
7812 done->uptodate = 1;
7813 ASSERT(!bio_flagged(bio, BIO_CLONED));
7814 bio_for_each_segment_all(bvec, bio, i)
7815 clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree,
7816 io_tree, done->start, bvec->bv_page,
7817 btrfs_ino(BTRFS_I(inode)), 0);
7818 end:
7819 complete(&done->done);
7820 bio_put(bio);
7821 }
7822
7823 static blk_status_t __btrfs_correct_data_nocsum(struct inode *inode,
7824 struct btrfs_io_bio *io_bio)
7825 {
7826 struct btrfs_fs_info *fs_info;
7827 struct bio_vec bvec;
7828 struct bvec_iter iter;
7829 struct btrfs_retry_complete done;
7830 u64 start;
7831 unsigned int pgoff;
7832 u32 sectorsize;
7833 int nr_sectors;
7834 blk_status_t ret;
7835 blk_status_t err = BLK_STS_OK;
7836
7837 fs_info = BTRFS_I(inode)->root->fs_info;
7838 sectorsize = fs_info->sectorsize;
7839
7840 start = io_bio->logical;
7841 done.inode = inode;
7842 io_bio->bio.bi_iter = io_bio->iter;
7843
7844 bio_for_each_segment(bvec, &io_bio->bio, iter) {
7845 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len);
7846 pgoff = bvec.bv_offset;
7847
7848 next_block_or_try_again:
7849 done.uptodate = 0;
7850 done.start = start;
7851 init_completion(&done.done);
7852
7853 ret = dio_read_error(inode, &io_bio->bio, bvec.bv_page,
7854 pgoff, start, start + sectorsize - 1,
7855 io_bio->mirror_num,
7856 btrfs_retry_endio_nocsum, &done);
7857 if (ret) {
7858 err = ret;
7859 goto next;
7860 }
7861
7862 wait_for_completion_io(&done.done);
7863
7864 if (!done.uptodate) {
7865 /* We might have another mirror, so try again */
7866 goto next_block_or_try_again;
7867 }
7868
7869 next:
7870 start += sectorsize;
7871
7872 nr_sectors--;
7873 if (nr_sectors) {
7874 pgoff += sectorsize;
7875 ASSERT(pgoff < PAGE_SIZE);
7876 goto next_block_or_try_again;
7877 }
7878 }
7879
7880 return err;
7881 }
7882
7883 static void btrfs_retry_endio(struct bio *bio)
7884 {
7885 struct btrfs_retry_complete *done = bio->bi_private;
7886 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
7887 struct extent_io_tree *io_tree, *failure_tree;
7888 struct inode *inode = done->inode;
7889 struct bio_vec *bvec;
7890 int uptodate;
7891 int ret;
7892 int i;
7893
7894 if (bio->bi_status)
7895 goto end;
7896
7897 uptodate = 1;
7898
7899 ASSERT(bio->bi_vcnt == 1);
7900 ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(done->inode));
7901
7902 io_tree = &BTRFS_I(inode)->io_tree;
7903 failure_tree = &BTRFS_I(inode)->io_failure_tree;
7904
7905 ASSERT(!bio_flagged(bio, BIO_CLONED));
7906 bio_for_each_segment_all(bvec, bio, i) {
7907 ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page,
7908 bvec->bv_offset, done->start,
7909 bvec->bv_len);
7910 if (!ret)
7911 clean_io_failure(BTRFS_I(inode)->root->fs_info,
7912 failure_tree, io_tree, done->start,
7913 bvec->bv_page,
7914 btrfs_ino(BTRFS_I(inode)),
7915 bvec->bv_offset);
7916 else
7917 uptodate = 0;
7918 }
7919
7920 done->uptodate = uptodate;
7921 end:
7922 complete(&done->done);
7923 bio_put(bio);
7924 }
7925
7926 static blk_status_t __btrfs_subio_endio_read(struct inode *inode,
7927 struct btrfs_io_bio *io_bio, blk_status_t err)
7928 {
7929 struct btrfs_fs_info *fs_info;
7930 struct bio_vec bvec;
7931 struct bvec_iter iter;
7932 struct btrfs_retry_complete done;
7933 u64 start;
7934 u64 offset = 0;
7935 u32 sectorsize;
7936 int nr_sectors;
7937 unsigned int pgoff;
7938 int csum_pos;
7939 bool uptodate = (err == 0);
7940 int ret;
7941 blk_status_t status;
7942
7943 fs_info = BTRFS_I(inode)->root->fs_info;
7944 sectorsize = fs_info->sectorsize;
7945
7946 err = BLK_STS_OK;
7947 start = io_bio->logical;
7948 done.inode = inode;
7949 io_bio->bio.bi_iter = io_bio->iter;
7950
7951 bio_for_each_segment(bvec, &io_bio->bio, iter) {
7952 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len);
7953
7954 pgoff = bvec.bv_offset;
7955 next_block:
7956 if (uptodate) {
7957 csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset);
7958 ret = __readpage_endio_check(inode, io_bio, csum_pos,
7959 bvec.bv_page, pgoff, start, sectorsize);
7960 if (likely(!ret))
7961 goto next;
7962 }
7963 try_again:
7964 done.uptodate = 0;
7965 done.start = start;
7966 init_completion(&done.done);
7967
7968 status = dio_read_error(inode, &io_bio->bio, bvec.bv_page,
7969 pgoff, start, start + sectorsize - 1,
7970 io_bio->mirror_num, btrfs_retry_endio,
7971 &done);
7972 if (status) {
7973 err = status;
7974 goto next;
7975 }
7976
7977 wait_for_completion_io(&done.done);
7978
7979 if (!done.uptodate) {
7980 /* We might have another mirror, so try again */
7981 goto try_again;
7982 }
7983 next:
7984 offset += sectorsize;
7985 start += sectorsize;
7986
7987 ASSERT(nr_sectors);
7988
7989 nr_sectors--;
7990 if (nr_sectors) {
7991 pgoff += sectorsize;
7992 ASSERT(pgoff < PAGE_SIZE);
7993 goto next_block;
7994 }
7995 }
7996
7997 return err;
7998 }
7999
8000 static blk_status_t btrfs_subio_endio_read(struct inode *inode,
8001 struct btrfs_io_bio *io_bio, blk_status_t err)
8002 {
8003 bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
8004
8005 if (skip_csum) {
8006 if (unlikely(err))
8007 return __btrfs_correct_data_nocsum(inode, io_bio);
8008 else
8009 return BLK_STS_OK;
8010 } else {
8011 return __btrfs_subio_endio_read(inode, io_bio, err);
8012 }
8013 }
8014
8015 static void btrfs_endio_direct_read(struct bio *bio)
8016 {
8017 struct btrfs_dio_private *dip = bio->bi_private;
8018 struct inode *inode = dip->inode;
8019 struct bio *dio_bio;
8020 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
8021 blk_status_t err = bio->bi_status;
8022
8023 if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED)
8024 err = btrfs_subio_endio_read(inode, io_bio, err);
8025
8026 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
8027 dip->logical_offset + dip->bytes - 1);
8028 dio_bio = dip->dio_bio;
8029
8030 kfree(dip);
8031
8032 dio_bio->bi_status = err;
8033 dio_end_io(dio_bio);
8034
8035 if (io_bio->end_io)
8036 io_bio->end_io(io_bio, blk_status_to_errno(err));
8037 bio_put(bio);
8038 }
8039
8040 static void __endio_write_update_ordered(struct inode *inode,
8041 const u64 offset, const u64 bytes,
8042 const bool uptodate)
8043 {
8044 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8045 struct btrfs_ordered_extent *ordered = NULL;
8046 struct btrfs_workqueue *wq;
8047 btrfs_work_func_t func;
8048 u64 ordered_offset = offset;
8049 u64 ordered_bytes = bytes;
8050 u64 last_offset;
8051
8052 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
8053 wq = fs_info->endio_freespace_worker;
8054 func = btrfs_freespace_write_helper;
8055 } else {
8056 wq = fs_info->endio_write_workers;
8057 func = btrfs_endio_write_helper;
8058 }
8059
8060 while (ordered_offset < offset + bytes) {
8061 last_offset = ordered_offset;
8062 if (btrfs_dec_test_first_ordered_pending(inode, &ordered,
8063 &ordered_offset,
8064 ordered_bytes,
8065 uptodate)) {
8066 btrfs_init_work(&ordered->work, func,
8067 finish_ordered_fn,
8068 NULL, NULL);
8069 btrfs_queue_work(wq, &ordered->work);
8070 }
8071 /*
8072 * If btrfs_dec_test_ordered_pending does not find any ordered
8073 * extent in the range, we can exit.
8074 */
8075 if (ordered_offset == last_offset)
8076 return;
8077 /*
8078 * Our bio might span multiple ordered extents. In this case
8079 * we keep goin until we have accounted the whole dio.
8080 */
8081 if (ordered_offset < offset + bytes) {
8082 ordered_bytes = offset + bytes - ordered_offset;
8083 ordered = NULL;
8084 }
8085 }
8086 }
8087
8088 static void btrfs_endio_direct_write(struct bio *bio)
8089 {
8090 struct btrfs_dio_private *dip = bio->bi_private;
8091 struct bio *dio_bio = dip->dio_bio;
8092
8093 __endio_write_update_ordered(dip->inode, dip->logical_offset,
8094 dip->bytes, !bio->bi_status);
8095
8096 kfree(dip);
8097
8098 dio_bio->bi_status = bio->bi_status;
8099 dio_end_io(dio_bio);
8100 bio_put(bio);
8101 }
8102
8103 static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data,
8104 struct bio *bio, u64 offset)
8105 {
8106 struct inode *inode = private_data;
8107 blk_status_t ret;
8108 ret = btrfs_csum_one_bio(inode, bio, offset, 1);
8109 BUG_ON(ret); /* -ENOMEM */
8110 return 0;
8111 }
8112
8113 static void btrfs_end_dio_bio(struct bio *bio)
8114 {
8115 struct btrfs_dio_private *dip = bio->bi_private;
8116 blk_status_t err = bio->bi_status;
8117
8118 if (err)
8119 btrfs_warn(BTRFS_I(dip->inode)->root->fs_info,
8120 "direct IO failed ino %llu rw %d,%u sector %#Lx len %u err no %d",
8121 btrfs_ino(BTRFS_I(dip->inode)), bio_op(bio),
8122 bio->bi_opf,
8123 (unsigned long long)bio->bi_iter.bi_sector,
8124 bio->bi_iter.bi_size, err);
8125
8126 if (dip->subio_endio)
8127 err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err);
8128
8129 if (err) {
8130 /*
8131 * We want to perceive the errors flag being set before
8132 * decrementing the reference count. We don't need a barrier
8133 * since atomic operations with a return value are fully
8134 * ordered as per atomic_t.txt
8135 */
8136 dip->errors = 1;
8137 }
8138
8139 /* if there are more bios still pending for this dio, just exit */
8140 if (!atomic_dec_and_test(&dip->pending_bios))
8141 goto out;
8142
8143 if (dip->errors) {
8144 bio_io_error(dip->orig_bio);
8145 } else {
8146 dip->dio_bio->bi_status = BLK_STS_OK;
8147 bio_endio(dip->orig_bio);
8148 }
8149 out:
8150 bio_put(bio);
8151 }
8152
8153 static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode,
8154 struct btrfs_dio_private *dip,
8155 struct bio *bio,
8156 u64 file_offset)
8157 {
8158 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
8159 struct btrfs_io_bio *orig_io_bio = btrfs_io_bio(dip->orig_bio);
8160 blk_status_t ret;
8161
8162 /*
8163 * We load all the csum data we need when we submit
8164 * the first bio to reduce the csum tree search and
8165 * contention.
8166 */
8167 if (dip->logical_offset == file_offset) {
8168 ret = btrfs_lookup_bio_sums_dio(inode, dip->orig_bio,
8169 file_offset);
8170 if (ret)
8171 return ret;
8172 }
8173
8174 if (bio == dip->orig_bio)
8175 return 0;
8176
8177 file_offset -= dip->logical_offset;
8178 file_offset >>= inode->i_sb->s_blocksize_bits;
8179 io_bio->csum = (u8 *)(((u32 *)orig_io_bio->csum) + file_offset);
8180
8181 return 0;
8182 }
8183
8184 static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio,
8185 struct inode *inode, u64 file_offset, int async_submit)
8186 {
8187 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8188 struct btrfs_dio_private *dip = bio->bi_private;
8189 bool write = bio_op(bio) == REQ_OP_WRITE;
8190 blk_status_t ret;
8191
8192 /* Check btrfs_submit_bio_hook() for rules about async submit. */
8193 if (async_submit)
8194 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
8195
8196 if (!write) {
8197 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
8198 if (ret)
8199 goto err;
8200 }
8201
8202 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
8203 goto map;
8204
8205 if (write && async_submit) {
8206 ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0,
8207 file_offset, inode,
8208 btrfs_submit_bio_start_direct_io);
8209 goto err;
8210 } else if (write) {
8211 /*
8212 * If we aren't doing async submit, calculate the csum of the
8213 * bio now.
8214 */
8215 ret = btrfs_csum_one_bio(inode, bio, file_offset, 1);
8216 if (ret)
8217 goto err;
8218 } else {
8219 ret = btrfs_lookup_and_bind_dio_csum(inode, dip, bio,
8220 file_offset);
8221 if (ret)
8222 goto err;
8223 }
8224 map:
8225 ret = btrfs_map_bio(fs_info, bio, 0, 0);
8226 err:
8227 return ret;
8228 }
8229
8230 static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
8231 {
8232 struct inode *inode = dip->inode;
8233 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8234 struct bio *bio;
8235 struct bio *orig_bio = dip->orig_bio;
8236 u64 start_sector = orig_bio->bi_iter.bi_sector;
8237 u64 file_offset = dip->logical_offset;
8238 u64 map_length;
8239 int async_submit = 0;
8240 u64 submit_len;
8241 int clone_offset = 0;
8242 int clone_len;
8243 int ret;
8244 blk_status_t status;
8245
8246 map_length = orig_bio->bi_iter.bi_size;
8247 submit_len = map_length;
8248 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9,
8249 &map_length, NULL, 0);
8250 if (ret)
8251 return -EIO;
8252
8253 if (map_length >= submit_len) {
8254 bio = orig_bio;
8255 dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED;
8256 goto submit;
8257 }
8258
8259 /* async crcs make it difficult to collect full stripe writes. */
8260 if (btrfs_data_alloc_profile(fs_info) & BTRFS_BLOCK_GROUP_RAID56_MASK)
8261 async_submit = 0;
8262 else
8263 async_submit = 1;
8264
8265 /* bio split */
8266 ASSERT(map_length <= INT_MAX);
8267 atomic_inc(&dip->pending_bios);
8268 do {
8269 clone_len = min_t(int, submit_len, map_length);
8270
8271 /*
8272 * This will never fail as it's passing GPF_NOFS and
8273 * the allocation is backed by btrfs_bioset.
8274 */
8275 bio = btrfs_bio_clone_partial(orig_bio, clone_offset,
8276 clone_len);
8277 bio->bi_private = dip;
8278 bio->bi_end_io = btrfs_end_dio_bio;
8279 btrfs_io_bio(bio)->logical = file_offset;
8280
8281 ASSERT(submit_len >= clone_len);
8282 submit_len -= clone_len;
8283 if (submit_len == 0)
8284 break;
8285
8286 /*
8287 * Increase the count before we submit the bio so we know
8288 * the end IO handler won't happen before we increase the
8289 * count. Otherwise, the dip might get freed before we're
8290 * done setting it up.
8291 */
8292 atomic_inc(&dip->pending_bios);
8293
8294 status = btrfs_submit_dio_bio(bio, inode, file_offset,
8295 async_submit);
8296 if (status) {
8297 bio_put(bio);
8298 atomic_dec(&dip->pending_bios);
8299 goto out_err;
8300 }
8301
8302 clone_offset += clone_len;
8303 start_sector += clone_len >> 9;
8304 file_offset += clone_len;
8305
8306 map_length = submit_len;
8307 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio),
8308 start_sector << 9, &map_length, NULL, 0);
8309 if (ret)
8310 goto out_err;
8311 } while (submit_len > 0);
8312
8313 submit:
8314 status = btrfs_submit_dio_bio(bio, inode, file_offset, async_submit);
8315 if (!status)
8316 return 0;
8317
8318 bio_put(bio);
8319 out_err:
8320 dip->errors = 1;
8321 /*
8322 * Before atomic variable goto zero, we must make sure dip->errors is
8323 * perceived to be set. This ordering is ensured by the fact that an
8324 * atomic operations with a return value are fully ordered as per
8325 * atomic_t.txt
8326 */
8327 if (atomic_dec_and_test(&dip->pending_bios))
8328 bio_io_error(dip->orig_bio);
8329
8330 /* bio_end_io() will handle error, so we needn't return it */
8331 return 0;
8332 }
8333
8334 static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
8335 loff_t file_offset)
8336 {
8337 struct btrfs_dio_private *dip = NULL;
8338 struct bio *bio = NULL;
8339 struct btrfs_io_bio *io_bio;
8340 bool write = (bio_op(dio_bio) == REQ_OP_WRITE);
8341 int ret = 0;
8342
8343 bio = btrfs_bio_clone(dio_bio);
8344
8345 dip = kzalloc(sizeof(*dip), GFP_NOFS);
8346 if (!dip) {
8347 ret = -ENOMEM;
8348 goto free_ordered;
8349 }
8350
8351 dip->private = dio_bio->bi_private;
8352 dip->inode = inode;
8353 dip->logical_offset = file_offset;
8354 dip->bytes = dio_bio->bi_iter.bi_size;
8355 dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9;
8356 bio->bi_private = dip;
8357 dip->orig_bio = bio;
8358 dip->dio_bio = dio_bio;
8359 atomic_set(&dip->pending_bios, 0);
8360 io_bio = btrfs_io_bio(bio);
8361 io_bio->logical = file_offset;
8362
8363 if (write) {
8364 bio->bi_end_io = btrfs_endio_direct_write;
8365 } else {
8366 bio->bi_end_io = btrfs_endio_direct_read;
8367 dip->subio_endio = btrfs_subio_endio_read;
8368 }
8369
8370 /*
8371 * Reset the range for unsubmitted ordered extents (to a 0 length range)
8372 * even if we fail to submit a bio, because in such case we do the
8373 * corresponding error handling below and it must not be done a second
8374 * time by btrfs_direct_IO().
8375 */
8376 if (write) {
8377 struct btrfs_dio_data *dio_data = current->journal_info;
8378
8379 dio_data->unsubmitted_oe_range_end = dip->logical_offset +
8380 dip->bytes;
8381 dio_data->unsubmitted_oe_range_start =
8382 dio_data->unsubmitted_oe_range_end;
8383 }
8384
8385 ret = btrfs_submit_direct_hook(dip);
8386 if (!ret)
8387 return;
8388
8389 if (io_bio->end_io)
8390 io_bio->end_io(io_bio, ret);
8391
8392 free_ordered:
8393 /*
8394 * If we arrived here it means either we failed to submit the dip
8395 * or we either failed to clone the dio_bio or failed to allocate the
8396 * dip. If we cloned the dio_bio and allocated the dip, we can just
8397 * call bio_endio against our io_bio so that we get proper resource
8398 * cleanup if we fail to submit the dip, otherwise, we must do the
8399 * same as btrfs_endio_direct_[write|read] because we can't call these
8400 * callbacks - they require an allocated dip and a clone of dio_bio.
8401 */
8402 if (bio && dip) {
8403 bio_io_error(bio);
8404 /*
8405 * The end io callbacks free our dip, do the final put on bio
8406 * and all the cleanup and final put for dio_bio (through
8407 * dio_end_io()).
8408 */
8409 dip = NULL;
8410 bio = NULL;
8411 } else {
8412 if (write)
8413 __endio_write_update_ordered(inode,
8414 file_offset,
8415 dio_bio->bi_iter.bi_size,
8416 false);
8417 else
8418 unlock_extent(&BTRFS_I(inode)->io_tree, file_offset,
8419 file_offset + dio_bio->bi_iter.bi_size - 1);
8420
8421 dio_bio->bi_status = BLK_STS_IOERR;
8422 /*
8423 * Releases and cleans up our dio_bio, no need to bio_put()
8424 * nor bio_endio()/bio_io_error() against dio_bio.
8425 */
8426 dio_end_io(dio_bio);
8427 }
8428 if (bio)
8429 bio_put(bio);
8430 kfree(dip);
8431 }
8432
8433 static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,
8434 const struct iov_iter *iter, loff_t offset)
8435 {
8436 int seg;
8437 int i;
8438 unsigned int blocksize_mask = fs_info->sectorsize - 1;
8439 ssize_t retval = -EINVAL;
8440
8441 if (offset & blocksize_mask)
8442 goto out;
8443
8444 if (iov_iter_alignment(iter) & blocksize_mask)
8445 goto out;
8446
8447 /* If this is a write we don't need to check anymore */
8448 if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter))
8449 return 0;
8450 /*
8451 * Check to make sure we don't have duplicate iov_base's in this
8452 * iovec, if so return EINVAL, otherwise we'll get csum errors
8453 * when reading back.
8454 */
8455 for (seg = 0; seg < iter->nr_segs; seg++) {
8456 for (i = seg + 1; i < iter->nr_segs; i++) {
8457 if (iter->iov[seg].iov_base == iter->iov[i].iov_base)
8458 goto out;
8459 }
8460 }
8461 retval = 0;
8462 out:
8463 return retval;
8464 }
8465
8466 static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
8467 {
8468 struct file *file = iocb->ki_filp;
8469 struct inode *inode = file->f_mapping->host;
8470 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8471 struct btrfs_dio_data dio_data = { 0 };
8472 struct extent_changeset *data_reserved = NULL;
8473 loff_t offset = iocb->ki_pos;
8474 size_t count = 0;
8475 int flags = 0;
8476 bool wakeup = true;
8477 bool relock = false;
8478 ssize_t ret;
8479
8480 if (check_direct_IO(fs_info, iter, offset))
8481 return 0;
8482
8483 inode_dio_begin(inode);
8484
8485 /*
8486 * The generic stuff only does filemap_write_and_wait_range, which
8487 * isn't enough if we've written compressed pages to this area, so
8488 * we need to flush the dirty pages again to make absolutely sure
8489 * that any outstanding dirty pages are on disk.
8490 */
8491 count = iov_iter_count(iter);
8492 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
8493 &BTRFS_I(inode)->runtime_flags))
8494 filemap_fdatawrite_range(inode->i_mapping, offset,
8495 offset + count - 1);
8496
8497 if (iov_iter_rw(iter) == WRITE) {
8498 /*
8499 * If the write DIO is beyond the EOF, we need update
8500 * the isize, but it is protected by i_mutex. So we can
8501 * not unlock the i_mutex at this case.
8502 */
8503 if (offset + count <= inode->i_size) {
8504 dio_data.overwrite = 1;
8505 inode_unlock(inode);
8506 relock = true;
8507 } else if (iocb->ki_flags & IOCB_NOWAIT) {
8508 ret = -EAGAIN;
8509 goto out;
8510 }
8511 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
8512 offset, count);
8513 if (ret)
8514 goto out;
8515
8516 /*
8517 * We need to know how many extents we reserved so that we can
8518 * do the accounting properly if we go over the number we
8519 * originally calculated. Abuse current->journal_info for this.
8520 */
8521 dio_data.reserve = round_up(count,
8522 fs_info->sectorsize);
8523 dio_data.unsubmitted_oe_range_start = (u64)offset;
8524 dio_data.unsubmitted_oe_range_end = (u64)offset;
8525 current->journal_info = &dio_data;
8526 down_read(&BTRFS_I(inode)->dio_sem);
8527 } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
8528 &BTRFS_I(inode)->runtime_flags)) {
8529 inode_dio_end(inode);
8530 flags = DIO_LOCKING | DIO_SKIP_HOLES;
8531 wakeup = false;
8532 }
8533
8534 ret = __blockdev_direct_IO(iocb, inode,
8535 fs_info->fs_devices->latest_bdev,
8536 iter, btrfs_get_blocks_direct, NULL,
8537 btrfs_submit_direct, flags);
8538 if (iov_iter_rw(iter) == WRITE) {
8539 up_read(&BTRFS_I(inode)->dio_sem);
8540 current->journal_info = NULL;
8541 if (ret < 0 && ret != -EIOCBQUEUED) {
8542 if (dio_data.reserve)
8543 btrfs_delalloc_release_space(inode, data_reserved,
8544 offset, dio_data.reserve, true);
8545 /*
8546 * On error we might have left some ordered extents
8547 * without submitting corresponding bios for them, so
8548 * cleanup them up to avoid other tasks getting them
8549 * and waiting for them to complete forever.
8550 */
8551 if (dio_data.unsubmitted_oe_range_start <
8552 dio_data.unsubmitted_oe_range_end)
8553 __endio_write_update_ordered(inode,
8554 dio_data.unsubmitted_oe_range_start,
8555 dio_data.unsubmitted_oe_range_end -
8556 dio_data.unsubmitted_oe_range_start,
8557 false);
8558 } else if (ret >= 0 && (size_t)ret < count)
8559 btrfs_delalloc_release_space(inode, data_reserved,
8560 offset, count - (size_t)ret, true);
8561 btrfs_delalloc_release_extents(BTRFS_I(inode), count, false);
8562 }
8563 out:
8564 if (wakeup)
8565 inode_dio_end(inode);
8566 if (relock)
8567 inode_lock(inode);
8568
8569 extent_changeset_free(data_reserved);
8570 return ret;
8571 }
8572
8573 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
8574
8575 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
8576 __u64 start, __u64 len)
8577 {
8578 int ret;
8579
8580 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
8581 if (ret)
8582 return ret;
8583
8584 return extent_fiemap(inode, fieinfo, start, len);
8585 }
8586
8587 int btrfs_readpage(struct file *file, struct page *page)
8588 {
8589 struct extent_io_tree *tree;
8590 tree = &BTRFS_I(page->mapping->host)->io_tree;
8591 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
8592 }
8593
8594 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
8595 {
8596 struct inode *inode = page->mapping->host;
8597 int ret;
8598
8599 if (current->flags & PF_MEMALLOC) {
8600 redirty_page_for_writepage(wbc, page);
8601 unlock_page(page);
8602 return 0;
8603 }
8604
8605 /*
8606 * If we are under memory pressure we will call this directly from the
8607 * VM, we need to make sure we have the inode referenced for the ordered
8608 * extent. If not just return like we didn't do anything.
8609 */
8610 if (!igrab(inode)) {
8611 redirty_page_for_writepage(wbc, page);
8612 return AOP_WRITEPAGE_ACTIVATE;
8613 }
8614 ret = extent_write_full_page(page, wbc);
8615 btrfs_add_delayed_iput(inode);
8616 return ret;
8617 }
8618
8619 static int btrfs_writepages(struct address_space *mapping,
8620 struct writeback_control *wbc)
8621 {
8622 return extent_writepages(mapping, wbc);
8623 }
8624
8625 static int
8626 btrfs_readpages(struct file *file, struct address_space *mapping,
8627 struct list_head *pages, unsigned nr_pages)
8628 {
8629 return extent_readpages(mapping, pages, nr_pages);
8630 }
8631
8632 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
8633 {
8634 int ret = try_release_extent_mapping(page, gfp_flags);
8635 if (ret == 1) {
8636 ClearPagePrivate(page);
8637 set_page_private(page, 0);
8638 put_page(page);
8639 }
8640 return ret;
8641 }
8642
8643 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
8644 {
8645 if (PageWriteback(page) || PageDirty(page))
8646 return 0;
8647 return __btrfs_releasepage(page, gfp_flags);
8648 }
8649
8650 static void btrfs_invalidatepage(struct page *page, unsigned int offset,
8651 unsigned int length)
8652 {
8653 struct inode *inode = page->mapping->host;
8654 struct extent_io_tree *tree;
8655 struct btrfs_ordered_extent *ordered;
8656 struct extent_state *cached_state = NULL;
8657 u64 page_start = page_offset(page);
8658 u64 page_end = page_start + PAGE_SIZE - 1;
8659 u64 start;
8660 u64 end;
8661 int inode_evicting = inode->i_state & I_FREEING;
8662
8663 /*
8664 * we have the page locked, so new writeback can't start,
8665 * and the dirty bit won't be cleared while we are here.
8666 *
8667 * Wait for IO on this page so that we can safely clear
8668 * the PagePrivate2 bit and do ordered accounting
8669 */
8670 wait_on_page_writeback(page);
8671
8672 tree = &BTRFS_I(inode)->io_tree;
8673 if (offset) {
8674 btrfs_releasepage(page, GFP_NOFS);
8675 return;
8676 }
8677
8678 if (!inode_evicting)
8679 lock_extent_bits(tree, page_start, page_end, &cached_state);
8680 again:
8681 start = page_start;
8682 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
8683 page_end - start + 1);
8684 if (ordered) {
8685 end = min(page_end, ordered->file_offset + ordered->len - 1);
8686 /*
8687 * IO on this page will never be started, so we need
8688 * to account for any ordered extents now
8689 */
8690 if (!inode_evicting)
8691 clear_extent_bit(tree, start, end,
8692 EXTENT_DIRTY | EXTENT_DELALLOC |
8693 EXTENT_DELALLOC_NEW |
8694 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
8695 EXTENT_DEFRAG, 1, 0, &cached_state);
8696 /*
8697 * whoever cleared the private bit is responsible
8698 * for the finish_ordered_io
8699 */
8700 if (TestClearPagePrivate2(page)) {
8701 struct btrfs_ordered_inode_tree *tree;
8702 u64 new_len;
8703
8704 tree = &BTRFS_I(inode)->ordered_tree;
8705
8706 spin_lock_irq(&tree->lock);
8707 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
8708 new_len = start - ordered->file_offset;
8709 if (new_len < ordered->truncated_len)
8710 ordered->truncated_len = new_len;
8711 spin_unlock_irq(&tree->lock);
8712
8713 if (btrfs_dec_test_ordered_pending(inode, &ordered,
8714 start,
8715 end - start + 1, 1))
8716 btrfs_finish_ordered_io(ordered);
8717 }
8718 btrfs_put_ordered_extent(ordered);
8719 if (!inode_evicting) {
8720 cached_state = NULL;
8721 lock_extent_bits(tree, start, end,
8722 &cached_state);
8723 }
8724
8725 start = end + 1;
8726 if (start < page_end)
8727 goto again;
8728 }
8729
8730 /*
8731 * Qgroup reserved space handler
8732 * Page here will be either
8733 * 1) Already written to disk
8734 * In this case, its reserved space is released from data rsv map
8735 * and will be freed by delayed_ref handler finally.
8736 * So even we call qgroup_free_data(), it won't decrease reserved
8737 * space.
8738 * 2) Not written to disk
8739 * This means the reserved space should be freed here. However,
8740 * if a truncate invalidates the page (by clearing PageDirty)
8741 * and the page is accounted for while allocating extent
8742 * in btrfs_check_data_free_space() we let delayed_ref to
8743 * free the entire extent.
8744 */
8745 if (PageDirty(page))
8746 btrfs_qgroup_free_data(inode, NULL, page_start, PAGE_SIZE);
8747 if (!inode_evicting) {
8748 clear_extent_bit(tree, page_start, page_end,
8749 EXTENT_LOCKED | EXTENT_DIRTY |
8750 EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
8751 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
8752 &cached_state);
8753
8754 __btrfs_releasepage(page, GFP_NOFS);
8755 }
8756
8757 ClearPageChecked(page);
8758 if (PagePrivate(page)) {
8759 ClearPagePrivate(page);
8760 set_page_private(page, 0);
8761 put_page(page);
8762 }
8763 }
8764
8765 /*
8766 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
8767 * called from a page fault handler when a page is first dirtied. Hence we must
8768 * be careful to check for EOF conditions here. We set the page up correctly
8769 * for a written page which means we get ENOSPC checking when writing into
8770 * holes and correct delalloc and unwritten extent mapping on filesystems that
8771 * support these features.
8772 *
8773 * We are not allowed to take the i_mutex here so we have to play games to
8774 * protect against truncate races as the page could now be beyond EOF. Because
8775 * truncate_setsize() writes the inode size before removing pages, once we have
8776 * the page lock we can determine safely if the page is beyond EOF. If it is not
8777 * beyond EOF, then the page is guaranteed safe against truncation until we
8778 * unlock the page.
8779 */
8780 vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
8781 {
8782 struct page *page = vmf->page;
8783 struct inode *inode = file_inode(vmf->vma->vm_file);
8784 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8785 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
8786 struct btrfs_ordered_extent *ordered;
8787 struct extent_state *cached_state = NULL;
8788 struct extent_changeset *data_reserved = NULL;
8789 char *kaddr;
8790 unsigned long zero_start;
8791 loff_t size;
8792 vm_fault_t ret;
8793 int ret2;
8794 int reserved = 0;
8795 u64 reserved_space;
8796 u64 page_start;
8797 u64 page_end;
8798 u64 end;
8799
8800 reserved_space = PAGE_SIZE;
8801
8802 sb_start_pagefault(inode->i_sb);
8803 page_start = page_offset(page);
8804 page_end = page_start + PAGE_SIZE - 1;
8805 end = page_end;
8806
8807 /*
8808 * Reserving delalloc space after obtaining the page lock can lead to
8809 * deadlock. For example, if a dirty page is locked by this function
8810 * and the call to btrfs_delalloc_reserve_space() ends up triggering
8811 * dirty page write out, then the btrfs_writepage() function could
8812 * end up waiting indefinitely to get a lock on the page currently
8813 * being processed by btrfs_page_mkwrite() function.
8814 */
8815 ret2 = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
8816 reserved_space);
8817 if (!ret2) {
8818 ret2 = file_update_time(vmf->vma->vm_file);
8819 reserved = 1;
8820 }
8821 if (ret2) {
8822 ret = vmf_error(ret2);
8823 if (reserved)
8824 goto out;
8825 goto out_noreserve;
8826 }
8827
8828 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
8829 again:
8830 lock_page(page);
8831 size = i_size_read(inode);
8832
8833 if ((page->mapping != inode->i_mapping) ||
8834 (page_start >= size)) {
8835 /* page got truncated out from underneath us */
8836 goto out_unlock;
8837 }
8838 wait_on_page_writeback(page);
8839
8840 lock_extent_bits(io_tree, page_start, page_end, &cached_state);
8841 set_page_extent_mapped(page);
8842
8843 /*
8844 * we can't set the delalloc bits if there are pending ordered
8845 * extents. Drop our locks and wait for them to finish
8846 */
8847 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
8848 PAGE_SIZE);
8849 if (ordered) {
8850 unlock_extent_cached(io_tree, page_start, page_end,
8851 &cached_state);
8852 unlock_page(page);
8853 btrfs_start_ordered_extent(inode, ordered, 1);
8854 btrfs_put_ordered_extent(ordered);
8855 goto again;
8856 }
8857
8858 if (page->index == ((size - 1) >> PAGE_SHIFT)) {
8859 reserved_space = round_up(size - page_start,
8860 fs_info->sectorsize);
8861 if (reserved_space < PAGE_SIZE) {
8862 end = page_start + reserved_space - 1;
8863 btrfs_delalloc_release_space(inode, data_reserved,
8864 page_start, PAGE_SIZE - reserved_space,
8865 true);
8866 }
8867 }
8868
8869 /*
8870 * page_mkwrite gets called when the page is firstly dirtied after it's
8871 * faulted in, but write(2) could also dirty a page and set delalloc
8872 * bits, thus in this case for space account reason, we still need to
8873 * clear any delalloc bits within this page range since we have to
8874 * reserve data&meta space before lock_page() (see above comments).
8875 */
8876 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end,
8877 EXTENT_DIRTY | EXTENT_DELALLOC |
8878 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
8879 0, 0, &cached_state);
8880
8881 ret2 = btrfs_set_extent_delalloc(inode, page_start, end, 0,
8882 &cached_state, 0);
8883 if (ret2) {
8884 unlock_extent_cached(io_tree, page_start, page_end,
8885 &cached_state);
8886 ret = VM_FAULT_SIGBUS;
8887 goto out_unlock;
8888 }
8889 ret2 = 0;
8890
8891 /* page is wholly or partially inside EOF */
8892 if (page_start + PAGE_SIZE > size)
8893 zero_start = size & ~PAGE_MASK;
8894 else
8895 zero_start = PAGE_SIZE;
8896
8897 if (zero_start != PAGE_SIZE) {
8898 kaddr = kmap(page);
8899 memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start);
8900 flush_dcache_page(page);
8901 kunmap(page);
8902 }
8903 ClearPageChecked(page);
8904 set_page_dirty(page);
8905 SetPageUptodate(page);
8906
8907 BTRFS_I(inode)->last_trans = fs_info->generation;
8908 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
8909 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
8910
8911 unlock_extent_cached(io_tree, page_start, page_end, &cached_state);
8912
8913 if (!ret2) {
8914 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, true);
8915 sb_end_pagefault(inode->i_sb);
8916 extent_changeset_free(data_reserved);
8917 return VM_FAULT_LOCKED;
8918 }
8919
8920 out_unlock:
8921 unlock_page(page);
8922 out:
8923 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, (ret != 0));
8924 btrfs_delalloc_release_space(inode, data_reserved, page_start,
8925 reserved_space, (ret != 0));
8926 out_noreserve:
8927 sb_end_pagefault(inode->i_sb);
8928 extent_changeset_free(data_reserved);
8929 return ret;
8930 }
8931
8932 static int btrfs_truncate(struct inode *inode, bool skip_writeback)
8933 {
8934 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8935 struct btrfs_root *root = BTRFS_I(inode)->root;
8936 struct btrfs_block_rsv *rsv;
8937 int ret;
8938 struct btrfs_trans_handle *trans;
8939 u64 mask = fs_info->sectorsize - 1;
8940 u64 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1);
8941
8942 if (!skip_writeback) {
8943 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
8944 (u64)-1);
8945 if (ret)
8946 return ret;
8947 }
8948
8949 /*
8950 * Yes ladies and gentlemen, this is indeed ugly. We have a couple of
8951 * things going on here:
8952 *
8953 * 1) We need to reserve space to update our inode.
8954 *
8955 * 2) We need to have something to cache all the space that is going to
8956 * be free'd up by the truncate operation, but also have some slack
8957 * space reserved in case it uses space during the truncate (thank you
8958 * very much snapshotting).
8959 *
8960 * And we need these to be separate. The fact is we can use a lot of
8961 * space doing the truncate, and we have no earthly idea how much space
8962 * we will use, so we need the truncate reservation to be separate so it
8963 * doesn't end up using space reserved for updating the inode. We also
8964 * need to be able to stop the transaction and start a new one, which
8965 * means we need to be able to update the inode several times, and we
8966 * have no idea of knowing how many times that will be, so we can't just
8967 * reserve 1 item for the entirety of the operation, so that has to be
8968 * done separately as well.
8969 *
8970 * So that leaves us with
8971 *
8972 * 1) rsv - for the truncate reservation, which we will steal from the
8973 * transaction reservation.
8974 * 2) fs_info->trans_block_rsv - this will have 1 items worth left for
8975 * updating the inode.
8976 */
8977 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
8978 if (!rsv)
8979 return -ENOMEM;
8980 rsv->size = min_size;
8981 rsv->failfast = 1;
8982
8983 /*
8984 * 1 for the truncate slack space
8985 * 1 for updating the inode.
8986 */
8987 trans = btrfs_start_transaction(root, 2);
8988 if (IS_ERR(trans)) {
8989 ret = PTR_ERR(trans);
8990 goto out;
8991 }
8992
8993 /* Migrate the slack space for the truncate to our reserve */
8994 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv,
8995 min_size, false);
8996 BUG_ON(ret);
8997
8998 /*
8999 * So if we truncate and then write and fsync we normally would just
9000 * write the extents that changed, which is a problem if we need to
9001 * first truncate that entire inode. So set this flag so we write out
9002 * all of the extents in the inode to the sync log so we're completely
9003 * safe.
9004 */
9005 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
9006 trans->block_rsv = rsv;
9007
9008 while (1) {
9009 ret = btrfs_truncate_inode_items(trans, root, inode,
9010 inode->i_size,
9011 BTRFS_EXTENT_DATA_KEY);
9012 trans->block_rsv = &fs_info->trans_block_rsv;
9013 if (ret != -ENOSPC && ret != -EAGAIN)
9014 break;
9015
9016 ret = btrfs_update_inode(trans, root, inode);
9017 if (ret)
9018 break;
9019
9020 btrfs_end_transaction(trans);
9021 btrfs_btree_balance_dirty(fs_info);
9022
9023 trans = btrfs_start_transaction(root, 2);
9024 if (IS_ERR(trans)) {
9025 ret = PTR_ERR(trans);
9026 trans = NULL;
9027 break;
9028 }
9029
9030 btrfs_block_rsv_release(fs_info, rsv, -1);
9031 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv,
9032 rsv, min_size, false);
9033 BUG_ON(ret); /* shouldn't happen */
9034 trans->block_rsv = rsv;
9035 }
9036
9037 /*
9038 * We can't call btrfs_truncate_block inside a trans handle as we could
9039 * deadlock with freeze, if we got NEED_TRUNCATE_BLOCK then we know
9040 * we've truncated everything except the last little bit, and can do
9041 * btrfs_truncate_block and then update the disk_i_size.
9042 */
9043 if (ret == NEED_TRUNCATE_BLOCK) {
9044 btrfs_end_transaction(trans);
9045 btrfs_btree_balance_dirty(fs_info);
9046
9047 ret = btrfs_truncate_block(inode, inode->i_size, 0, 0);
9048 if (ret)
9049 goto out;
9050 trans = btrfs_start_transaction(root, 1);
9051 if (IS_ERR(trans)) {
9052 ret = PTR_ERR(trans);
9053 goto out;
9054 }
9055 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
9056 }
9057
9058 if (trans) {
9059 int ret2;
9060
9061 trans->block_rsv = &fs_info->trans_block_rsv;
9062 ret2 = btrfs_update_inode(trans, root, inode);
9063 if (ret2 && !ret)
9064 ret = ret2;
9065
9066 ret2 = btrfs_end_transaction(trans);
9067 if (ret2 && !ret)
9068 ret = ret2;
9069 btrfs_btree_balance_dirty(fs_info);
9070 }
9071 out:
9072 btrfs_free_block_rsv(fs_info, rsv);
9073
9074 return ret;
9075 }
9076
9077 /*
9078 * create a new subvolume directory/inode (helper for the ioctl).
9079 */
9080 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
9081 struct btrfs_root *new_root,
9082 struct btrfs_root *parent_root,
9083 u64 new_dirid)
9084 {
9085 struct inode *inode;
9086 int err;
9087 u64 index = 0;
9088
9089 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
9090 new_dirid, new_dirid,
9091 S_IFDIR | (~current_umask() & S_IRWXUGO),
9092 &index);
9093 if (IS_ERR(inode))
9094 return PTR_ERR(inode);
9095 inode->i_op = &btrfs_dir_inode_operations;
9096 inode->i_fop = &btrfs_dir_file_operations;
9097
9098 set_nlink(inode, 1);
9099 btrfs_i_size_write(BTRFS_I(inode), 0);
9100 unlock_new_inode(inode);
9101
9102 err = btrfs_subvol_inherit_props(trans, new_root, parent_root);
9103 if (err)
9104 btrfs_err(new_root->fs_info,
9105 "error inheriting subvolume %llu properties: %d",
9106 new_root->root_key.objectid, err);
9107
9108 err = btrfs_update_inode(trans, new_root, inode);
9109
9110 iput(inode);
9111 return err;
9112 }
9113
9114 struct inode *btrfs_alloc_inode(struct super_block *sb)
9115 {
9116 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
9117 struct btrfs_inode *ei;
9118 struct inode *inode;
9119
9120 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_KERNEL);
9121 if (!ei)
9122 return NULL;
9123
9124 ei->root = NULL;
9125 ei->generation = 0;
9126 ei->last_trans = 0;
9127 ei->last_sub_trans = 0;
9128 ei->logged_trans = 0;
9129 ei->delalloc_bytes = 0;
9130 ei->new_delalloc_bytes = 0;
9131 ei->defrag_bytes = 0;
9132 ei->disk_i_size = 0;
9133 ei->flags = 0;
9134 ei->csum_bytes = 0;
9135 ei->index_cnt = (u64)-1;
9136 ei->dir_index = 0;
9137 ei->last_unlink_trans = 0;
9138 ei->last_log_commit = 0;
9139
9140 spin_lock_init(&ei->lock);
9141 ei->outstanding_extents = 0;
9142 if (sb->s_magic != BTRFS_TEST_MAGIC)
9143 btrfs_init_metadata_block_rsv(fs_info, &ei->block_rsv,
9144 BTRFS_BLOCK_RSV_DELALLOC);
9145 ei->runtime_flags = 0;
9146 ei->prop_compress = BTRFS_COMPRESS_NONE;
9147 ei->defrag_compress = BTRFS_COMPRESS_NONE;
9148
9149 ei->delayed_node = NULL;
9150
9151 ei->i_otime.tv_sec = 0;
9152 ei->i_otime.tv_nsec = 0;
9153
9154 inode = &ei->vfs_inode;
9155 extent_map_tree_init(&ei->extent_tree);
9156 extent_io_tree_init(&ei->io_tree, inode);
9157 extent_io_tree_init(&ei->io_failure_tree, inode);
9158 ei->io_tree.track_uptodate = 1;
9159 ei->io_failure_tree.track_uptodate = 1;
9160 atomic_set(&ei->sync_writers, 0);
9161 mutex_init(&ei->log_mutex);
9162 mutex_init(&ei->delalloc_mutex);
9163 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
9164 INIT_LIST_HEAD(&ei->delalloc_inodes);
9165 INIT_LIST_HEAD(&ei->delayed_iput);
9166 RB_CLEAR_NODE(&ei->rb_node);
9167 init_rwsem(&ei->dio_sem);
9168
9169 return inode;
9170 }
9171
9172 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
9173 void btrfs_test_destroy_inode(struct inode *inode)
9174 {
9175 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
9176 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
9177 }
9178 #endif
9179
9180 static void btrfs_i_callback(struct rcu_head *head)
9181 {
9182 struct inode *inode = container_of(head, struct inode, i_rcu);
9183 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
9184 }
9185
9186 void btrfs_destroy_inode(struct inode *inode)
9187 {
9188 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
9189 struct btrfs_ordered_extent *ordered;
9190 struct btrfs_root *root = BTRFS_I(inode)->root;
9191
9192 WARN_ON(!hlist_empty(&inode->i_dentry));
9193 WARN_ON(inode->i_data.nrpages);
9194 WARN_ON(BTRFS_I(inode)->block_rsv.reserved);
9195 WARN_ON(BTRFS_I(inode)->block_rsv.size);
9196 WARN_ON(BTRFS_I(inode)->outstanding_extents);
9197 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
9198 WARN_ON(BTRFS_I(inode)->new_delalloc_bytes);
9199 WARN_ON(BTRFS_I(inode)->csum_bytes);
9200 WARN_ON(BTRFS_I(inode)->defrag_bytes);
9201
9202 /*
9203 * This can happen where we create an inode, but somebody else also
9204 * created the same inode and we need to destroy the one we already
9205 * created.
9206 */
9207 if (!root)
9208 goto free;
9209
9210 while (1) {
9211 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
9212 if (!ordered)
9213 break;
9214 else {
9215 btrfs_err(fs_info,
9216 "found ordered extent %llu %llu on inode cleanup",
9217 ordered->file_offset, ordered->len);
9218 btrfs_remove_ordered_extent(inode, ordered);
9219 btrfs_put_ordered_extent(ordered);
9220 btrfs_put_ordered_extent(ordered);
9221 }
9222 }
9223 btrfs_qgroup_check_reserved_leak(inode);
9224 inode_tree_del(inode);
9225 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
9226 free:
9227 call_rcu(&inode->i_rcu, btrfs_i_callback);
9228 }
9229
9230 int btrfs_drop_inode(struct inode *inode)
9231 {
9232 struct btrfs_root *root = BTRFS_I(inode)->root;
9233
9234 if (root == NULL)
9235 return 1;
9236
9237 /* the snap/subvol tree is on deleting */
9238 if (btrfs_root_refs(&root->root_item) == 0)
9239 return 1;
9240 else
9241 return generic_drop_inode(inode);
9242 }
9243
9244 static void init_once(void *foo)
9245 {
9246 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
9247
9248 inode_init_once(&ei->vfs_inode);
9249 }
9250
9251 void __cold btrfs_destroy_cachep(void)
9252 {
9253 /*
9254 * Make sure all delayed rcu free inodes are flushed before we
9255 * destroy cache.
9256 */
9257 rcu_barrier();
9258 kmem_cache_destroy(btrfs_inode_cachep);
9259 kmem_cache_destroy(btrfs_trans_handle_cachep);
9260 kmem_cache_destroy(btrfs_path_cachep);
9261 kmem_cache_destroy(btrfs_free_space_cachep);
9262 }
9263
9264 int __init btrfs_init_cachep(void)
9265 {
9266 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
9267 sizeof(struct btrfs_inode), 0,
9268 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT,
9269 init_once);
9270 if (!btrfs_inode_cachep)
9271 goto fail;
9272
9273 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
9274 sizeof(struct btrfs_trans_handle), 0,
9275 SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL);
9276 if (!btrfs_trans_handle_cachep)
9277 goto fail;
9278
9279 btrfs_path_cachep = kmem_cache_create("btrfs_path",
9280 sizeof(struct btrfs_path), 0,
9281 SLAB_MEM_SPREAD, NULL);
9282 if (!btrfs_path_cachep)
9283 goto fail;
9284
9285 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
9286 sizeof(struct btrfs_free_space), 0,
9287 SLAB_MEM_SPREAD, NULL);
9288 if (!btrfs_free_space_cachep)
9289 goto fail;
9290
9291 return 0;
9292 fail:
9293 btrfs_destroy_cachep();
9294 return -ENOMEM;
9295 }
9296
9297 static int btrfs_getattr(const struct path *path, struct kstat *stat,
9298 u32 request_mask, unsigned int flags)
9299 {
9300 u64 delalloc_bytes;
9301 struct inode *inode = d_inode(path->dentry);
9302 u32 blocksize = inode->i_sb->s_blocksize;
9303 u32 bi_flags = BTRFS_I(inode)->flags;
9304
9305 stat->result_mask |= STATX_BTIME;
9306 stat->btime.tv_sec = BTRFS_I(inode)->i_otime.tv_sec;
9307 stat->btime.tv_nsec = BTRFS_I(inode)->i_otime.tv_nsec;
9308 if (bi_flags & BTRFS_INODE_APPEND)
9309 stat->attributes |= STATX_ATTR_APPEND;
9310 if (bi_flags & BTRFS_INODE_COMPRESS)
9311 stat->attributes |= STATX_ATTR_COMPRESSED;
9312 if (bi_flags & BTRFS_INODE_IMMUTABLE)
9313 stat->attributes |= STATX_ATTR_IMMUTABLE;
9314 if (bi_flags & BTRFS_INODE_NODUMP)
9315 stat->attributes |= STATX_ATTR_NODUMP;
9316
9317 stat->attributes_mask |= (STATX_ATTR_APPEND |
9318 STATX_ATTR_COMPRESSED |
9319 STATX_ATTR_IMMUTABLE |
9320 STATX_ATTR_NODUMP);
9321
9322 generic_fillattr(inode, stat);
9323 stat->dev = BTRFS_I(inode)->root->anon_dev;
9324
9325 spin_lock(&BTRFS_I(inode)->lock);
9326 delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes;
9327 spin_unlock(&BTRFS_I(inode)->lock);
9328 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
9329 ALIGN(delalloc_bytes, blocksize)) >> 9;
9330 return 0;
9331 }
9332
9333 static int btrfs_rename_exchange(struct inode *old_dir,
9334 struct dentry *old_dentry,
9335 struct inode *new_dir,
9336 struct dentry *new_dentry)
9337 {
9338 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb);
9339 struct btrfs_trans_handle *trans;
9340 struct btrfs_root *root = BTRFS_I(old_dir)->root;
9341 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
9342 struct inode *new_inode = new_dentry->d_inode;
9343 struct inode *old_inode = old_dentry->d_inode;
9344 struct timespec64 ctime = current_time(old_inode);
9345 struct dentry *parent;
9346 u64 old_ino = btrfs_ino(BTRFS_I(old_inode));
9347 u64 new_ino = btrfs_ino(BTRFS_I(new_inode));
9348 u64 old_idx = 0;
9349 u64 new_idx = 0;
9350 u64 root_objectid;
9351 int ret;
9352 bool root_log_pinned = false;
9353 bool dest_log_pinned = false;
9354 struct btrfs_log_ctx ctx_root;
9355 struct btrfs_log_ctx ctx_dest;
9356 bool sync_log_root = false;
9357 bool sync_log_dest = false;
9358 bool commit_transaction = false;
9359
9360 /* we only allow rename subvolume link between subvolumes */
9361 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
9362 return -EXDEV;
9363
9364 btrfs_init_log_ctx(&ctx_root, old_inode);
9365 btrfs_init_log_ctx(&ctx_dest, new_inode);
9366
9367 /* close the race window with snapshot create/destroy ioctl */
9368 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9369 down_read(&fs_info->subvol_sem);
9370 if (new_ino == BTRFS_FIRST_FREE_OBJECTID)
9371 down_read(&fs_info->subvol_sem);
9372
9373 /*
9374 * We want to reserve the absolute worst case amount of items. So if
9375 * both inodes are subvols and we need to unlink them then that would
9376 * require 4 item modifications, but if they are both normal inodes it
9377 * would require 5 item modifications, so we'll assume their normal
9378 * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items
9379 * should cover the worst case number of items we'll modify.
9380 */
9381 trans = btrfs_start_transaction(root, 12);
9382 if (IS_ERR(trans)) {
9383 ret = PTR_ERR(trans);
9384 goto out_notrans;
9385 }
9386
9387 /*
9388 * We need to find a free sequence number both in the source and
9389 * in the destination directory for the exchange.
9390 */
9391 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx);
9392 if (ret)
9393 goto out_fail;
9394 ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx);
9395 if (ret)
9396 goto out_fail;
9397
9398 BTRFS_I(old_inode)->dir_index = 0ULL;
9399 BTRFS_I(new_inode)->dir_index = 0ULL;
9400
9401 /* Reference for the source. */
9402 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
9403 /* force full log commit if subvolume involved. */
9404 btrfs_set_log_full_commit(fs_info, trans);
9405 } else {
9406 btrfs_pin_log_trans(root);
9407 root_log_pinned = true;
9408 ret = btrfs_insert_inode_ref(trans, dest,
9409 new_dentry->d_name.name,
9410 new_dentry->d_name.len,
9411 old_ino,
9412 btrfs_ino(BTRFS_I(new_dir)),
9413 old_idx);
9414 if (ret)
9415 goto out_fail;
9416 }
9417
9418 /* And now for the dest. */
9419 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
9420 /* force full log commit if subvolume involved. */
9421 btrfs_set_log_full_commit(fs_info, trans);
9422 } else {
9423 btrfs_pin_log_trans(dest);
9424 dest_log_pinned = true;
9425 ret = btrfs_insert_inode_ref(trans, root,
9426 old_dentry->d_name.name,
9427 old_dentry->d_name.len,
9428 new_ino,
9429 btrfs_ino(BTRFS_I(old_dir)),
9430 new_idx);
9431 if (ret)
9432 goto out_fail;
9433 }
9434
9435 /* Update inode version and ctime/mtime. */
9436 inode_inc_iversion(old_dir);
9437 inode_inc_iversion(new_dir);
9438 inode_inc_iversion(old_inode);
9439 inode_inc_iversion(new_inode);
9440 old_dir->i_ctime = old_dir->i_mtime = ctime;
9441 new_dir->i_ctime = new_dir->i_mtime = ctime;
9442 old_inode->i_ctime = ctime;
9443 new_inode->i_ctime = ctime;
9444
9445 if (old_dentry->d_parent != new_dentry->d_parent) {
9446 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir),
9447 BTRFS_I(old_inode), 1);
9448 btrfs_record_unlink_dir(trans, BTRFS_I(new_dir),
9449 BTRFS_I(new_inode), 1);
9450 }
9451
9452 /* src is a subvolume */
9453 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
9454 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
9455 ret = btrfs_unlink_subvol(trans, old_dir, root_objectid,
9456 old_dentry->d_name.name,
9457 old_dentry->d_name.len);
9458 } else { /* src is an inode */
9459 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir),
9460 BTRFS_I(old_dentry->d_inode),
9461 old_dentry->d_name.name,
9462 old_dentry->d_name.len);
9463 if (!ret)
9464 ret = btrfs_update_inode(trans, root, old_inode);
9465 }
9466 if (ret) {
9467 btrfs_abort_transaction(trans, ret);
9468 goto out_fail;
9469 }
9470
9471 /* dest is a subvolume */
9472 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
9473 root_objectid = BTRFS_I(new_inode)->root->root_key.objectid;
9474 ret = btrfs_unlink_subvol(trans, new_dir, root_objectid,
9475 new_dentry->d_name.name,
9476 new_dentry->d_name.len);
9477 } else { /* dest is an inode */
9478 ret = __btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir),
9479 BTRFS_I(new_dentry->d_inode),
9480 new_dentry->d_name.name,
9481 new_dentry->d_name.len);
9482 if (!ret)
9483 ret = btrfs_update_inode(trans, dest, new_inode);
9484 }
9485 if (ret) {
9486 btrfs_abort_transaction(trans, ret);
9487 goto out_fail;
9488 }
9489
9490 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
9491 new_dentry->d_name.name,
9492 new_dentry->d_name.len, 0, old_idx);
9493 if (ret) {
9494 btrfs_abort_transaction(trans, ret);
9495 goto out_fail;
9496 }
9497
9498 ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode),
9499 old_dentry->d_name.name,
9500 old_dentry->d_name.len, 0, new_idx);
9501 if (ret) {
9502 btrfs_abort_transaction(trans, ret);
9503 goto out_fail;
9504 }
9505
9506 if (old_inode->i_nlink == 1)
9507 BTRFS_I(old_inode)->dir_index = old_idx;
9508 if (new_inode->i_nlink == 1)
9509 BTRFS_I(new_inode)->dir_index = new_idx;
9510
9511 if (root_log_pinned) {
9512 parent = new_dentry->d_parent;
9513 ret = btrfs_log_new_name(trans, BTRFS_I(old_inode),
9514 BTRFS_I(old_dir), parent,
9515 false, &ctx_root);
9516 if (ret == BTRFS_NEED_LOG_SYNC)
9517 sync_log_root = true;
9518 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9519 commit_transaction = true;
9520 ret = 0;
9521 btrfs_end_log_trans(root);
9522 root_log_pinned = false;
9523 }
9524 if (dest_log_pinned) {
9525 if (!commit_transaction) {
9526 parent = old_dentry->d_parent;
9527 ret = btrfs_log_new_name(trans, BTRFS_I(new_inode),
9528 BTRFS_I(new_dir), parent,
9529 false, &ctx_dest);
9530 if (ret == BTRFS_NEED_LOG_SYNC)
9531 sync_log_dest = true;
9532 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9533 commit_transaction = true;
9534 ret = 0;
9535 }
9536 btrfs_end_log_trans(dest);
9537 dest_log_pinned = false;
9538 }
9539 out_fail:
9540 /*
9541 * If we have pinned a log and an error happened, we unpin tasks
9542 * trying to sync the log and force them to fallback to a transaction
9543 * commit if the log currently contains any of the inodes involved in
9544 * this rename operation (to ensure we do not persist a log with an
9545 * inconsistent state for any of these inodes or leading to any
9546 * inconsistencies when replayed). If the transaction was aborted, the
9547 * abortion reason is propagated to userspace when attempting to commit
9548 * the transaction. If the log does not contain any of these inodes, we
9549 * allow the tasks to sync it.
9550 */
9551 if (ret && (root_log_pinned || dest_log_pinned)) {
9552 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) ||
9553 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) ||
9554 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) ||
9555 (new_inode &&
9556 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation)))
9557 btrfs_set_log_full_commit(fs_info, trans);
9558
9559 if (root_log_pinned) {
9560 btrfs_end_log_trans(root);
9561 root_log_pinned = false;
9562 }
9563 if (dest_log_pinned) {
9564 btrfs_end_log_trans(dest);
9565 dest_log_pinned = false;
9566 }
9567 }
9568 if (!ret && sync_log_root && !commit_transaction) {
9569 ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root,
9570 &ctx_root);
9571 if (ret)
9572 commit_transaction = true;
9573 }
9574 if (!ret && sync_log_dest && !commit_transaction) {
9575 ret = btrfs_sync_log(trans, BTRFS_I(new_inode)->root,
9576 &ctx_dest);
9577 if (ret)
9578 commit_transaction = true;
9579 }
9580 if (commit_transaction) {
9581 ret = btrfs_commit_transaction(trans);
9582 } else {
9583 int ret2;
9584
9585 ret2 = btrfs_end_transaction(trans);
9586 ret = ret ? ret : ret2;
9587 }
9588 out_notrans:
9589 if (new_ino == BTRFS_FIRST_FREE_OBJECTID)
9590 up_read(&fs_info->subvol_sem);
9591 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9592 up_read(&fs_info->subvol_sem);
9593
9594 return ret;
9595 }
9596
9597 static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans,
9598 struct btrfs_root *root,
9599 struct inode *dir,
9600 struct dentry *dentry)
9601 {
9602 int ret;
9603 struct inode *inode;
9604 u64 objectid;
9605 u64 index;
9606
9607 ret = btrfs_find_free_ino(root, &objectid);
9608 if (ret)
9609 return ret;
9610
9611 inode = btrfs_new_inode(trans, root, dir,
9612 dentry->d_name.name,
9613 dentry->d_name.len,
9614 btrfs_ino(BTRFS_I(dir)),
9615 objectid,
9616 S_IFCHR | WHITEOUT_MODE,
9617 &index);
9618
9619 if (IS_ERR(inode)) {
9620 ret = PTR_ERR(inode);
9621 return ret;
9622 }
9623
9624 inode->i_op = &btrfs_special_inode_operations;
9625 init_special_inode(inode, inode->i_mode,
9626 WHITEOUT_DEV);
9627
9628 ret = btrfs_init_inode_security(trans, inode, dir,
9629 &dentry->d_name);
9630 if (ret)
9631 goto out;
9632
9633 ret = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
9634 BTRFS_I(inode), 0, index);
9635 if (ret)
9636 goto out;
9637
9638 ret = btrfs_update_inode(trans, root, inode);
9639 out:
9640 unlock_new_inode(inode);
9641 if (ret)
9642 inode_dec_link_count(inode);
9643 iput(inode);
9644
9645 return ret;
9646 }
9647
9648 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
9649 struct inode *new_dir, struct dentry *new_dentry,
9650 unsigned int flags)
9651 {
9652 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb);
9653 struct btrfs_trans_handle *trans;
9654 unsigned int trans_num_items;
9655 struct btrfs_root *root = BTRFS_I(old_dir)->root;
9656 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
9657 struct inode *new_inode = d_inode(new_dentry);
9658 struct inode *old_inode = d_inode(old_dentry);
9659 u64 index = 0;
9660 u64 root_objectid;
9661 int ret;
9662 u64 old_ino = btrfs_ino(BTRFS_I(old_inode));
9663 bool log_pinned = false;
9664 struct btrfs_log_ctx ctx;
9665 bool sync_log = false;
9666 bool commit_transaction = false;
9667
9668 if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
9669 return -EPERM;
9670
9671 /* we only allow rename subvolume link between subvolumes */
9672 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
9673 return -EXDEV;
9674
9675 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
9676 (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID))
9677 return -ENOTEMPTY;
9678
9679 if (S_ISDIR(old_inode->i_mode) && new_inode &&
9680 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
9681 return -ENOTEMPTY;
9682
9683
9684 /* check for collisions, even if the name isn't there */
9685 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino,
9686 new_dentry->d_name.name,
9687 new_dentry->d_name.len);
9688
9689 if (ret) {
9690 if (ret == -EEXIST) {
9691 /* we shouldn't get
9692 * eexist without a new_inode */
9693 if (WARN_ON(!new_inode)) {
9694 return ret;
9695 }
9696 } else {
9697 /* maybe -EOVERFLOW */
9698 return ret;
9699 }
9700 }
9701 ret = 0;
9702
9703 /*
9704 * we're using rename to replace one file with another. Start IO on it
9705 * now so we don't add too much work to the end of the transaction
9706 */
9707 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size)
9708 filemap_flush(old_inode->i_mapping);
9709
9710 /* close the racy window with snapshot create/destroy ioctl */
9711 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9712 down_read(&fs_info->subvol_sem);
9713 /*
9714 * We want to reserve the absolute worst case amount of items. So if
9715 * both inodes are subvols and we need to unlink them then that would
9716 * require 4 item modifications, but if they are both normal inodes it
9717 * would require 5 item modifications, so we'll assume they are normal
9718 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
9719 * should cover the worst case number of items we'll modify.
9720 * If our rename has the whiteout flag, we need more 5 units for the
9721 * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item
9722 * when selinux is enabled).
9723 */
9724 trans_num_items = 11;
9725 if (flags & RENAME_WHITEOUT)
9726 trans_num_items += 5;
9727 trans = btrfs_start_transaction(root, trans_num_items);
9728 if (IS_ERR(trans)) {
9729 ret = PTR_ERR(trans);
9730 goto out_notrans;
9731 }
9732
9733 if (dest != root)
9734 btrfs_record_root_in_trans(trans, dest);
9735
9736 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index);
9737 if (ret)
9738 goto out_fail;
9739
9740 BTRFS_I(old_inode)->dir_index = 0ULL;
9741 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
9742 /* force full log commit if subvolume involved. */
9743 btrfs_set_log_full_commit(fs_info, trans);
9744 } else {
9745 btrfs_pin_log_trans(root);
9746 log_pinned = true;
9747 ret = btrfs_insert_inode_ref(trans, dest,
9748 new_dentry->d_name.name,
9749 new_dentry->d_name.len,
9750 old_ino,
9751 btrfs_ino(BTRFS_I(new_dir)), index);
9752 if (ret)
9753 goto out_fail;
9754 }
9755
9756 inode_inc_iversion(old_dir);
9757 inode_inc_iversion(new_dir);
9758 inode_inc_iversion(old_inode);
9759 old_dir->i_ctime = old_dir->i_mtime =
9760 new_dir->i_ctime = new_dir->i_mtime =
9761 old_inode->i_ctime = current_time(old_dir);
9762
9763 if (old_dentry->d_parent != new_dentry->d_parent)
9764 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir),
9765 BTRFS_I(old_inode), 1);
9766
9767 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
9768 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
9769 ret = btrfs_unlink_subvol(trans, old_dir, root_objectid,
9770 old_dentry->d_name.name,
9771 old_dentry->d_name.len);
9772 } else {
9773 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir),
9774 BTRFS_I(d_inode(old_dentry)),
9775 old_dentry->d_name.name,
9776 old_dentry->d_name.len);
9777 if (!ret)
9778 ret = btrfs_update_inode(trans, root, old_inode);
9779 }
9780 if (ret) {
9781 btrfs_abort_transaction(trans, ret);
9782 goto out_fail;
9783 }
9784
9785 if (new_inode) {
9786 inode_inc_iversion(new_inode);
9787 new_inode->i_ctime = current_time(new_inode);
9788 if (unlikely(btrfs_ino(BTRFS_I(new_inode)) ==
9789 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
9790 root_objectid = BTRFS_I(new_inode)->location.objectid;
9791 ret = btrfs_unlink_subvol(trans, new_dir, root_objectid,
9792 new_dentry->d_name.name,
9793 new_dentry->d_name.len);
9794 BUG_ON(new_inode->i_nlink == 0);
9795 } else {
9796 ret = btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir),
9797 BTRFS_I(d_inode(new_dentry)),
9798 new_dentry->d_name.name,
9799 new_dentry->d_name.len);
9800 }
9801 if (!ret && new_inode->i_nlink == 0)
9802 ret = btrfs_orphan_add(trans,
9803 BTRFS_I(d_inode(new_dentry)));
9804 if (ret) {
9805 btrfs_abort_transaction(trans, ret);
9806 goto out_fail;
9807 }
9808 }
9809
9810 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
9811 new_dentry->d_name.name,
9812 new_dentry->d_name.len, 0, index);
9813 if (ret) {
9814 btrfs_abort_transaction(trans, ret);
9815 goto out_fail;
9816 }
9817
9818 if (old_inode->i_nlink == 1)
9819 BTRFS_I(old_inode)->dir_index = index;
9820
9821 if (log_pinned) {
9822 struct dentry *parent = new_dentry->d_parent;
9823
9824 btrfs_init_log_ctx(&ctx, old_inode);
9825 ret = btrfs_log_new_name(trans, BTRFS_I(old_inode),
9826 BTRFS_I(old_dir), parent,
9827 false, &ctx);
9828 if (ret == BTRFS_NEED_LOG_SYNC)
9829 sync_log = true;
9830 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9831 commit_transaction = true;
9832 ret = 0;
9833 btrfs_end_log_trans(root);
9834 log_pinned = false;
9835 }
9836
9837 if (flags & RENAME_WHITEOUT) {
9838 ret = btrfs_whiteout_for_rename(trans, root, old_dir,
9839 old_dentry);
9840
9841 if (ret) {
9842 btrfs_abort_transaction(trans, ret);
9843 goto out_fail;
9844 }
9845 }
9846 out_fail:
9847 /*
9848 * If we have pinned the log and an error happened, we unpin tasks
9849 * trying to sync the log and force them to fallback to a transaction
9850 * commit if the log currently contains any of the inodes involved in
9851 * this rename operation (to ensure we do not persist a log with an
9852 * inconsistent state for any of these inodes or leading to any
9853 * inconsistencies when replayed). If the transaction was aborted, the
9854 * abortion reason is propagated to userspace when attempting to commit
9855 * the transaction. If the log does not contain any of these inodes, we
9856 * allow the tasks to sync it.
9857 */
9858 if (ret && log_pinned) {
9859 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) ||
9860 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) ||
9861 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) ||
9862 (new_inode &&
9863 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation)))
9864 btrfs_set_log_full_commit(fs_info, trans);
9865
9866 btrfs_end_log_trans(root);
9867 log_pinned = false;
9868 }
9869 if (!ret && sync_log) {
9870 ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root, &ctx);
9871 if (ret)
9872 commit_transaction = true;
9873 }
9874 if (commit_transaction) {
9875 ret = btrfs_commit_transaction(trans);
9876 } else {
9877 int ret2;
9878
9879 ret2 = btrfs_end_transaction(trans);
9880 ret = ret ? ret : ret2;
9881 }
9882 out_notrans:
9883 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9884 up_read(&fs_info->subvol_sem);
9885
9886 return ret;
9887 }
9888
9889 static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
9890 struct inode *new_dir, struct dentry *new_dentry,
9891 unsigned int flags)
9892 {
9893 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
9894 return -EINVAL;
9895
9896 if (flags & RENAME_EXCHANGE)
9897 return btrfs_rename_exchange(old_dir, old_dentry, new_dir,
9898 new_dentry);
9899
9900 return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
9901 }
9902
9903 struct btrfs_delalloc_work {
9904 struct inode *inode;
9905 struct completion completion;
9906 struct list_head list;
9907 struct btrfs_work work;
9908 };
9909
9910 static void btrfs_run_delalloc_work(struct btrfs_work *work)
9911 {
9912 struct btrfs_delalloc_work *delalloc_work;
9913 struct inode *inode;
9914
9915 delalloc_work = container_of(work, struct btrfs_delalloc_work,
9916 work);
9917 inode = delalloc_work->inode;
9918 filemap_flush(inode->i_mapping);
9919 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
9920 &BTRFS_I(inode)->runtime_flags))
9921 filemap_flush(inode->i_mapping);
9922
9923 iput(inode);
9924 complete(&delalloc_work->completion);
9925 }
9926
9927 static struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode)
9928 {
9929 struct btrfs_delalloc_work *work;
9930
9931 work = kmalloc(sizeof(*work), GFP_NOFS);
9932 if (!work)
9933 return NULL;
9934
9935 init_completion(&work->completion);
9936 INIT_LIST_HEAD(&work->list);
9937 work->inode = inode;
9938 WARN_ON_ONCE(!inode);
9939 btrfs_init_work(&work->work, btrfs_flush_delalloc_helper,
9940 btrfs_run_delalloc_work, NULL, NULL);
9941
9942 return work;
9943 }
9944
9945 /*
9946 * some fairly slow code that needs optimization. This walks the list
9947 * of all the inodes with pending delalloc and forces them to disk.
9948 */
9949 static int start_delalloc_inodes(struct btrfs_root *root, int nr)
9950 {
9951 struct btrfs_inode *binode;
9952 struct inode *inode;
9953 struct btrfs_delalloc_work *work, *next;
9954 struct list_head works;
9955 struct list_head splice;
9956 int ret = 0;
9957
9958 INIT_LIST_HEAD(&works);
9959 INIT_LIST_HEAD(&splice);
9960
9961 mutex_lock(&root->delalloc_mutex);
9962 spin_lock(&root->delalloc_lock);
9963 list_splice_init(&root->delalloc_inodes, &splice);
9964 while (!list_empty(&splice)) {
9965 binode = list_entry(splice.next, struct btrfs_inode,
9966 delalloc_inodes);
9967
9968 list_move_tail(&binode->delalloc_inodes,
9969 &root->delalloc_inodes);
9970 inode = igrab(&binode->vfs_inode);
9971 if (!inode) {
9972 cond_resched_lock(&root->delalloc_lock);
9973 continue;
9974 }
9975 spin_unlock(&root->delalloc_lock);
9976
9977 work = btrfs_alloc_delalloc_work(inode);
9978 if (!work) {
9979 iput(inode);
9980 ret = -ENOMEM;
9981 goto out;
9982 }
9983 list_add_tail(&work->list, &works);
9984 btrfs_queue_work(root->fs_info->flush_workers,
9985 &work->work);
9986 ret++;
9987 if (nr != -1 && ret >= nr)
9988 goto out;
9989 cond_resched();
9990 spin_lock(&root->delalloc_lock);
9991 }
9992 spin_unlock(&root->delalloc_lock);
9993
9994 out:
9995 list_for_each_entry_safe(work, next, &works, list) {
9996 list_del_init(&work->list);
9997 wait_for_completion(&work->completion);
9998 kfree(work);
9999 }
10000
10001 if (!list_empty(&splice)) {
10002 spin_lock(&root->delalloc_lock);
10003 list_splice_tail(&splice, &root->delalloc_inodes);
10004 spin_unlock(&root->delalloc_lock);
10005 }
10006 mutex_unlock(&root->delalloc_mutex);
10007 return ret;
10008 }
10009
10010 int btrfs_start_delalloc_inodes(struct btrfs_root *root)
10011 {
10012 struct btrfs_fs_info *fs_info = root->fs_info;
10013 int ret;
10014
10015 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
10016 return -EROFS;
10017
10018 ret = start_delalloc_inodes(root, -1);
10019 if (ret > 0)
10020 ret = 0;
10021 return ret;
10022 }
10023
10024 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int nr)
10025 {
10026 struct btrfs_root *root;
10027 struct list_head splice;
10028 int ret;
10029
10030 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
10031 return -EROFS;
10032
10033 INIT_LIST_HEAD(&splice);
10034
10035 mutex_lock(&fs_info->delalloc_root_mutex);
10036 spin_lock(&fs_info->delalloc_root_lock);
10037 list_splice_init(&fs_info->delalloc_roots, &splice);
10038 while (!list_empty(&splice) && nr) {
10039 root = list_first_entry(&splice, struct btrfs_root,
10040 delalloc_root);
10041 root = btrfs_grab_fs_root(root);
10042 BUG_ON(!root);
10043 list_move_tail(&root->delalloc_root,
10044 &fs_info->delalloc_roots);
10045 spin_unlock(&fs_info->delalloc_root_lock);
10046
10047 ret = start_delalloc_inodes(root, nr);
10048 btrfs_put_fs_root(root);
10049 if (ret < 0)
10050 goto out;
10051
10052 if (nr != -1) {
10053 nr -= ret;
10054 WARN_ON(nr < 0);
10055 }
10056 spin_lock(&fs_info->delalloc_root_lock);
10057 }
10058 spin_unlock(&fs_info->delalloc_root_lock);
10059
10060 ret = 0;
10061 out:
10062 if (!list_empty(&splice)) {
10063 spin_lock(&fs_info->delalloc_root_lock);
10064 list_splice_tail(&splice, &fs_info->delalloc_roots);
10065 spin_unlock(&fs_info->delalloc_root_lock);
10066 }
10067 mutex_unlock(&fs_info->delalloc_root_mutex);
10068 return ret;
10069 }
10070
10071 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
10072 const char *symname)
10073 {
10074 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
10075 struct btrfs_trans_handle *trans;
10076 struct btrfs_root *root = BTRFS_I(dir)->root;
10077 struct btrfs_path *path;
10078 struct btrfs_key key;
10079 struct inode *inode = NULL;
10080 int err;
10081 u64 objectid;
10082 u64 index = 0;
10083 int name_len;
10084 int datasize;
10085 unsigned long ptr;
10086 struct btrfs_file_extent_item *ei;
10087 struct extent_buffer *leaf;
10088
10089 name_len = strlen(symname);
10090 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info))
10091 return -ENAMETOOLONG;
10092
10093 /*
10094 * 2 items for inode item and ref
10095 * 2 items for dir items
10096 * 1 item for updating parent inode item
10097 * 1 item for the inline extent item
10098 * 1 item for xattr if selinux is on
10099 */
10100 trans = btrfs_start_transaction(root, 7);
10101 if (IS_ERR(trans))
10102 return PTR_ERR(trans);
10103
10104 err = btrfs_find_free_ino(root, &objectid);
10105 if (err)
10106 goto out_unlock;
10107
10108 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
10109 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)),
10110 objectid, S_IFLNK|S_IRWXUGO, &index);
10111 if (IS_ERR(inode)) {
10112 err = PTR_ERR(inode);
10113 inode = NULL;
10114 goto out_unlock;
10115 }
10116
10117 /*
10118 * If the active LSM wants to access the inode during
10119 * d_instantiate it needs these. Smack checks to see
10120 * if the filesystem supports xattrs by looking at the
10121 * ops vector.
10122 */
10123 inode->i_fop = &btrfs_file_operations;
10124 inode->i_op = &btrfs_file_inode_operations;
10125 inode->i_mapping->a_ops = &btrfs_aops;
10126 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
10127
10128 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
10129 if (err)
10130 goto out_unlock;
10131
10132 path = btrfs_alloc_path();
10133 if (!path) {
10134 err = -ENOMEM;
10135 goto out_unlock;
10136 }
10137 key.objectid = btrfs_ino(BTRFS_I(inode));
10138 key.offset = 0;
10139 key.type = BTRFS_EXTENT_DATA_KEY;
10140 datasize = btrfs_file_extent_calc_inline_size(name_len);
10141 err = btrfs_insert_empty_item(trans, root, path, &key,
10142 datasize);
10143 if (err) {
10144 btrfs_free_path(path);
10145 goto out_unlock;
10146 }
10147 leaf = path->nodes[0];
10148 ei = btrfs_item_ptr(leaf, path->slots[0],
10149 struct btrfs_file_extent_item);
10150 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
10151 btrfs_set_file_extent_type(leaf, ei,
10152 BTRFS_FILE_EXTENT_INLINE);
10153 btrfs_set_file_extent_encryption(leaf, ei, 0);
10154 btrfs_set_file_extent_compression(leaf, ei, 0);
10155 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
10156 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
10157
10158 ptr = btrfs_file_extent_inline_start(ei);
10159 write_extent_buffer(leaf, symname, ptr, name_len);
10160 btrfs_mark_buffer_dirty(leaf);
10161 btrfs_free_path(path);
10162
10163 inode->i_op = &btrfs_symlink_inode_operations;
10164 inode_nohighmem(inode);
10165 inode->i_mapping->a_ops = &btrfs_aops;
10166 inode_set_bytes(inode, name_len);
10167 btrfs_i_size_write(BTRFS_I(inode), name_len);
10168 err = btrfs_update_inode(trans, root, inode);
10169 /*
10170 * Last step, add directory indexes for our symlink inode. This is the
10171 * last step to avoid extra cleanup of these indexes if an error happens
10172 * elsewhere above.
10173 */
10174 if (!err)
10175 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
10176 BTRFS_I(inode), 0, index);
10177 if (err)
10178 goto out_unlock;
10179
10180 d_instantiate_new(dentry, inode);
10181
10182 out_unlock:
10183 btrfs_end_transaction(trans);
10184 if (err && inode) {
10185 inode_dec_link_count(inode);
10186 discard_new_inode(inode);
10187 }
10188 btrfs_btree_balance_dirty(fs_info);
10189 return err;
10190 }
10191
10192 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
10193 u64 start, u64 num_bytes, u64 min_size,
10194 loff_t actual_len, u64 *alloc_hint,
10195 struct btrfs_trans_handle *trans)
10196 {
10197 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
10198 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
10199 struct extent_map *em;
10200 struct btrfs_root *root = BTRFS_I(inode)->root;
10201 struct btrfs_key ins;
10202 u64 cur_offset = start;
10203 u64 i_size;
10204 u64 cur_bytes;
10205 u64 last_alloc = (u64)-1;
10206 int ret = 0;
10207 bool own_trans = true;
10208 u64 end = start + num_bytes - 1;
10209
10210 if (trans)
10211 own_trans = false;
10212 while (num_bytes > 0) {
10213 if (own_trans) {
10214 trans = btrfs_start_transaction(root, 3);
10215 if (IS_ERR(trans)) {
10216 ret = PTR_ERR(trans);
10217 break;
10218 }
10219 }
10220
10221 cur_bytes = min_t(u64, num_bytes, SZ_256M);
10222 cur_bytes = max(cur_bytes, min_size);
10223 /*
10224 * If we are severely fragmented we could end up with really
10225 * small allocations, so if the allocator is returning small
10226 * chunks lets make its job easier by only searching for those
10227 * sized chunks.
10228 */
10229 cur_bytes = min(cur_bytes, last_alloc);
10230 ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes,
10231 min_size, 0, *alloc_hint, &ins, 1, 0);
10232 if (ret) {
10233 if (own_trans)
10234 btrfs_end_transaction(trans);
10235 break;
10236 }
10237 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
10238
10239 last_alloc = ins.offset;
10240 ret = insert_reserved_file_extent(trans, inode,
10241 cur_offset, ins.objectid,
10242 ins.offset, ins.offset,
10243 ins.offset, 0, 0, 0,
10244 BTRFS_FILE_EXTENT_PREALLOC);
10245 if (ret) {
10246 btrfs_free_reserved_extent(fs_info, ins.objectid,
10247 ins.offset, 0);
10248 btrfs_abort_transaction(trans, ret);
10249 if (own_trans)
10250 btrfs_end_transaction(trans);
10251 break;
10252 }
10253
10254 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
10255 cur_offset + ins.offset -1, 0);
10256
10257 em = alloc_extent_map();
10258 if (!em) {
10259 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
10260 &BTRFS_I(inode)->runtime_flags);
10261 goto next;
10262 }
10263
10264 em->start = cur_offset;
10265 em->orig_start = cur_offset;
10266 em->len = ins.offset;
10267 em->block_start = ins.objectid;
10268 em->block_len = ins.offset;
10269 em->orig_block_len = ins.offset;
10270 em->ram_bytes = ins.offset;
10271 em->bdev = fs_info->fs_devices->latest_bdev;
10272 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
10273 em->generation = trans->transid;
10274
10275 while (1) {
10276 write_lock(&em_tree->lock);
10277 ret = add_extent_mapping(em_tree, em, 1);
10278 write_unlock(&em_tree->lock);
10279 if (ret != -EEXIST)
10280 break;
10281 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
10282 cur_offset + ins.offset - 1,
10283 0);
10284 }
10285 free_extent_map(em);
10286 next:
10287 num_bytes -= ins.offset;
10288 cur_offset += ins.offset;
10289 *alloc_hint = ins.objectid + ins.offset;
10290
10291 inode_inc_iversion(inode);
10292 inode->i_ctime = current_time(inode);
10293 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
10294 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
10295 (actual_len > inode->i_size) &&
10296 (cur_offset > inode->i_size)) {
10297 if (cur_offset > actual_len)
10298 i_size = actual_len;
10299 else
10300 i_size = cur_offset;
10301 i_size_write(inode, i_size);
10302 btrfs_ordered_update_i_size(inode, i_size, NULL);
10303 }
10304
10305 ret = btrfs_update_inode(trans, root, inode);
10306
10307 if (ret) {
10308 btrfs_abort_transaction(trans, ret);
10309 if (own_trans)
10310 btrfs_end_transaction(trans);
10311 break;
10312 }
10313
10314 if (own_trans)
10315 btrfs_end_transaction(trans);
10316 }
10317 if (cur_offset < end)
10318 btrfs_free_reserved_data_space(inode, NULL, cur_offset,
10319 end - cur_offset + 1);
10320 return ret;
10321 }
10322
10323 int btrfs_prealloc_file_range(struct inode *inode, int mode,
10324 u64 start, u64 num_bytes, u64 min_size,
10325 loff_t actual_len, u64 *alloc_hint)
10326 {
10327 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
10328 min_size, actual_len, alloc_hint,
10329 NULL);
10330 }
10331
10332 int btrfs_prealloc_file_range_trans(struct inode *inode,
10333 struct btrfs_trans_handle *trans, int mode,
10334 u64 start, u64 num_bytes, u64 min_size,
10335 loff_t actual_len, u64 *alloc_hint)
10336 {
10337 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
10338 min_size, actual_len, alloc_hint, trans);
10339 }
10340
10341 static int btrfs_set_page_dirty(struct page *page)
10342 {
10343 return __set_page_dirty_nobuffers(page);
10344 }
10345
10346 static int btrfs_permission(struct inode *inode, int mask)
10347 {
10348 struct btrfs_root *root = BTRFS_I(inode)->root;
10349 umode_t mode = inode->i_mode;
10350
10351 if (mask & MAY_WRITE &&
10352 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
10353 if (btrfs_root_readonly(root))
10354 return -EROFS;
10355 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
10356 return -EACCES;
10357 }
10358 return generic_permission(inode, mask);
10359 }
10360
10361 static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
10362 {
10363 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
10364 struct btrfs_trans_handle *trans;
10365 struct btrfs_root *root = BTRFS_I(dir)->root;
10366 struct inode *inode = NULL;
10367 u64 objectid;
10368 u64 index;
10369 int ret = 0;
10370
10371 /*
10372 * 5 units required for adding orphan entry
10373 */
10374 trans = btrfs_start_transaction(root, 5);
10375 if (IS_ERR(trans))
10376 return PTR_ERR(trans);
10377
10378 ret = btrfs_find_free_ino(root, &objectid);
10379 if (ret)
10380 goto out;
10381
10382 inode = btrfs_new_inode(trans, root, dir, NULL, 0,
10383 btrfs_ino(BTRFS_I(dir)), objectid, mode, &index);
10384 if (IS_ERR(inode)) {
10385 ret = PTR_ERR(inode);
10386 inode = NULL;
10387 goto out;
10388 }
10389
10390 inode->i_fop = &btrfs_file_operations;
10391 inode->i_op = &btrfs_file_inode_operations;
10392
10393 inode->i_mapping->a_ops = &btrfs_aops;
10394 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
10395
10396 ret = btrfs_init_inode_security(trans, inode, dir, NULL);
10397 if (ret)
10398 goto out;
10399
10400 ret = btrfs_update_inode(trans, root, inode);
10401 if (ret)
10402 goto out;
10403 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
10404 if (ret)
10405 goto out;
10406
10407 /*
10408 * We set number of links to 0 in btrfs_new_inode(), and here we set
10409 * it to 1 because d_tmpfile() will issue a warning if the count is 0,
10410 * through:
10411 *
10412 * d_tmpfile() -> inode_dec_link_count() -> drop_nlink()
10413 */
10414 set_nlink(inode, 1);
10415 d_tmpfile(dentry, inode);
10416 unlock_new_inode(inode);
10417 mark_inode_dirty(inode);
10418 out:
10419 btrfs_end_transaction(trans);
10420 if (ret && inode)
10421 discard_new_inode(inode);
10422 btrfs_btree_balance_dirty(fs_info);
10423 return ret;
10424 }
10425
10426 __attribute__((const))
10427 static int btrfs_readpage_io_failed_hook(struct page *page, int failed_mirror)
10428 {
10429 return -EAGAIN;
10430 }
10431
10432 static void btrfs_check_extent_io_range(void *private_data, const char *caller,
10433 u64 start, u64 end)
10434 {
10435 struct inode *inode = private_data;
10436 u64 isize;
10437
10438 isize = i_size_read(inode);
10439 if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) {
10440 btrfs_debug_rl(BTRFS_I(inode)->root->fs_info,
10441 "%s: ino %llu isize %llu odd range [%llu,%llu]",
10442 caller, btrfs_ino(BTRFS_I(inode)), isize, start, end);
10443 }
10444 }
10445
10446 void btrfs_set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
10447 {
10448 struct inode *inode = tree->private_data;
10449 unsigned long index = start >> PAGE_SHIFT;
10450 unsigned long end_index = end >> PAGE_SHIFT;
10451 struct page *page;
10452
10453 while (index <= end_index) {
10454 page = find_get_page(inode->i_mapping, index);
10455 ASSERT(page); /* Pages should be in the extent_io_tree */
10456 set_page_writeback(page);
10457 put_page(page);
10458 index++;
10459 }
10460 }
10461
10462 static const struct inode_operations btrfs_dir_inode_operations = {
10463 .getattr = btrfs_getattr,
10464 .lookup = btrfs_lookup,
10465 .create = btrfs_create,
10466 .unlink = btrfs_unlink,
10467 .link = btrfs_link,
10468 .mkdir = btrfs_mkdir,
10469 .rmdir = btrfs_rmdir,
10470 .rename = btrfs_rename2,
10471 .symlink = btrfs_symlink,
10472 .setattr = btrfs_setattr,
10473 .mknod = btrfs_mknod,
10474 .listxattr = btrfs_listxattr,
10475 .permission = btrfs_permission,
10476 .get_acl = btrfs_get_acl,
10477 .set_acl = btrfs_set_acl,
10478 .update_time = btrfs_update_time,
10479 .tmpfile = btrfs_tmpfile,
10480 };
10481 static const struct inode_operations btrfs_dir_ro_inode_operations = {
10482 .lookup = btrfs_lookup,
10483 .permission = btrfs_permission,
10484 .update_time = btrfs_update_time,
10485 };
10486
10487 static const struct file_operations btrfs_dir_file_operations = {
10488 .llseek = generic_file_llseek,
10489 .read = generic_read_dir,
10490 .iterate_shared = btrfs_real_readdir,
10491 .open = btrfs_opendir,
10492 .unlocked_ioctl = btrfs_ioctl,
10493 #ifdef CONFIG_COMPAT
10494 .compat_ioctl = btrfs_compat_ioctl,
10495 #endif
10496 .release = btrfs_release_file,
10497 .fsync = btrfs_sync_file,
10498 };
10499
10500 static const struct extent_io_ops btrfs_extent_io_ops = {
10501 /* mandatory callbacks */
10502 .submit_bio_hook = btrfs_submit_bio_hook,
10503 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
10504 .readpage_io_failed_hook = btrfs_readpage_io_failed_hook,
10505
10506 /* optional callbacks */
10507 .fill_delalloc = run_delalloc_range,
10508 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
10509 .writepage_start_hook = btrfs_writepage_start_hook,
10510 .set_bit_hook = btrfs_set_bit_hook,
10511 .clear_bit_hook = btrfs_clear_bit_hook,
10512 .merge_extent_hook = btrfs_merge_extent_hook,
10513 .split_extent_hook = btrfs_split_extent_hook,
10514 .check_extent_io_range = btrfs_check_extent_io_range,
10515 };
10516
10517 /*
10518 * btrfs doesn't support the bmap operation because swapfiles
10519 * use bmap to make a mapping of extents in the file. They assume
10520 * these extents won't change over the life of the file and they
10521 * use the bmap result to do IO directly to the drive.
10522 *
10523 * the btrfs bmap call would return logical addresses that aren't
10524 * suitable for IO and they also will change frequently as COW
10525 * operations happen. So, swapfile + btrfs == corruption.
10526 *
10527 * For now we're avoiding this by dropping bmap.
10528 */
10529 static const struct address_space_operations btrfs_aops = {
10530 .readpage = btrfs_readpage,
10531 .writepage = btrfs_writepage,
10532 .writepages = btrfs_writepages,
10533 .readpages = btrfs_readpages,
10534 .direct_IO = btrfs_direct_IO,
10535 .invalidatepage = btrfs_invalidatepage,
10536 .releasepage = btrfs_releasepage,
10537 .set_page_dirty = btrfs_set_page_dirty,
10538 .error_remove_page = generic_error_remove_page,
10539 };
10540
10541 static const struct inode_operations btrfs_file_inode_operations = {
10542 .getattr = btrfs_getattr,
10543 .setattr = btrfs_setattr,
10544 .listxattr = btrfs_listxattr,
10545 .permission = btrfs_permission,
10546 .fiemap = btrfs_fiemap,
10547 .get_acl = btrfs_get_acl,
10548 .set_acl = btrfs_set_acl,
10549 .update_time = btrfs_update_time,
10550 };
10551 static const struct inode_operations btrfs_special_inode_operations = {
10552 .getattr = btrfs_getattr,
10553 .setattr = btrfs_setattr,
10554 .permission = btrfs_permission,
10555 .listxattr = btrfs_listxattr,
10556 .get_acl = btrfs_get_acl,
10557 .set_acl = btrfs_set_acl,
10558 .update_time = btrfs_update_time,
10559 };
10560 static const struct inode_operations btrfs_symlink_inode_operations = {
10561 .get_link = page_get_link,
10562 .getattr = btrfs_getattr,
10563 .setattr = btrfs_setattr,
10564 .permission = btrfs_permission,
10565 .listxattr = btrfs_listxattr,
10566 .update_time = btrfs_update_time,
10567 };
10568
10569 const struct dentry_operations btrfs_dentry_operations = {
10570 .d_delete = btrfs_dentry_delete,
10571 };
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