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c1d7c514 | 1 | // SPDX-License-Identifier: GPL-2.0 |
6cbd5570 CM |
2 | /* |
3 | * Copyright (C) 2007 Oracle. All rights reserved. | |
6cbd5570 CM |
4 | */ |
5 | ||
886322e8 | 6 | #include <linux/err.h> |
8ea05e3a | 7 | #include <linux/uuid.h> |
3768f368 | 8 | #include "ctree.h" |
5eda7b5e | 9 | #include "transaction.h" |
3768f368 CM |
10 | #include "disk-io.h" |
11 | #include "print-tree.h" | |
28a32d2b JB |
12 | #include "qgroup.h" |
13 | #include "space-info.h" | |
3768f368 | 14 | |
8ea05e3a AB |
15 | /* |
16 | * Read a root item from the tree. In case we detect a root item smaller then | |
17 | * sizeof(root_item), we know it's an old version of the root structure and | |
18 | * initialize all new fields to zero. The same happens if we detect mismatching | |
19 | * generation numbers as then we know the root was once mounted with an older | |
20 | * kernel that was not aware of the root item structure change. | |
21 | */ | |
171170c1 ST |
22 | static void btrfs_read_root_item(struct extent_buffer *eb, int slot, |
23 | struct btrfs_root_item *item) | |
8ea05e3a | 24 | { |
f65e25e3 | 25 | u32 len; |
8ea05e3a AB |
26 | int need_reset = 0; |
27 | ||
3212fa14 | 28 | len = btrfs_item_size(eb, slot); |
8ea05e3a | 29 | read_extent_buffer(eb, item, btrfs_item_ptr_offset(eb, slot), |
f65e25e3 | 30 | min_t(u32, len, sizeof(*item))); |
8ea05e3a AB |
31 | if (len < sizeof(*item)) |
32 | need_reset = 1; | |
33 | if (!need_reset && btrfs_root_generation(item) | |
34 | != btrfs_root_generation_v2(item)) { | |
35 | if (btrfs_root_generation_v2(item) != 0) { | |
f14d104d | 36 | btrfs_warn(eb->fs_info, |
5d163e0e | 37 | "mismatching generation and generation_v2 found in root item. This root was probably mounted with an older kernel. Resetting all new fields."); |
8ea05e3a AB |
38 | } |
39 | need_reset = 1; | |
40 | } | |
41 | if (need_reset) { | |
a2c5062f KC |
42 | /* Clear all members from generation_v2 onwards. */ |
43 | memset_startat(item, 0, generation_v2); | |
807fc790 | 44 | generate_random_guid(item->uuid); |
8ea05e3a AB |
45 | } |
46 | } | |
47 | ||
d352ac68 | 48 | /* |
cb517eab MX |
49 | * btrfs_find_root - lookup the root by the key. |
50 | * root: the root of the root tree | |
51 | * search_key: the key to search | |
52 | * path: the path we search | |
53 | * root_item: the root item of the tree we look for | |
01327610 | 54 | * root_key: the root key of the tree we look for |
cb517eab | 55 | * |
01327610 | 56 | * If ->offset of 'search_key' is -1ULL, it means we are not sure the offset |
cb517eab MX |
57 | * of the search key, just lookup the root with the highest offset for a |
58 | * given objectid. | |
59 | * | |
60 | * If we find something return 0, otherwise > 0, < 0 on error. | |
d352ac68 | 61 | */ |
310712b2 | 62 | int btrfs_find_root(struct btrfs_root *root, const struct btrfs_key *search_key, |
cb517eab MX |
63 | struct btrfs_path *path, struct btrfs_root_item *root_item, |
64 | struct btrfs_key *root_key) | |
3768f368 | 65 | { |
5f39d397 CM |
66 | struct btrfs_key found_key; |
67 | struct extent_buffer *l; | |
3768f368 CM |
68 | int ret; |
69 | int slot; | |
70 | ||
cb517eab | 71 | ret = btrfs_search_slot(NULL, root, search_key, path, 0, 0); |
3768f368 | 72 | if (ret < 0) |
cb517eab | 73 | return ret; |
5f39d397 | 74 | |
cb517eab MX |
75 | if (search_key->offset != -1ULL) { /* the search key is exact */ |
76 | if (ret > 0) | |
77 | goto out; | |
78 | } else { | |
79 | BUG_ON(ret == 0); /* Logical error */ | |
80 | if (path->slots[0] == 0) | |
81 | goto out; | |
82 | path->slots[0]--; | |
83 | ret = 0; | |
76dda93c | 84 | } |
cb517eab | 85 | |
5f39d397 | 86 | l = path->nodes[0]; |
cb517eab MX |
87 | slot = path->slots[0]; |
88 | ||
5f39d397 | 89 | btrfs_item_key_to_cpu(l, &found_key, slot); |
cb517eab | 90 | if (found_key.objectid != search_key->objectid || |
76dda93c | 91 | found_key.type != BTRFS_ROOT_ITEM_KEY) { |
3768f368 CM |
92 | ret = 1; |
93 | goto out; | |
94 | } | |
8ea05e3a | 95 | |
cb517eab MX |
96 | if (root_item) |
97 | btrfs_read_root_item(l, slot, root_item); | |
98 | if (root_key) | |
99 | memcpy(root_key, &found_key, sizeof(found_key)); | |
3768f368 | 100 | out: |
cb517eab | 101 | btrfs_release_path(path); |
3768f368 CM |
102 | return ret; |
103 | } | |
104 | ||
bf5f32ec MF |
105 | void btrfs_set_root_node(struct btrfs_root_item *item, |
106 | struct extent_buffer *node) | |
5d4f98a2 YZ |
107 | { |
108 | btrfs_set_root_bytenr(item, node->start); | |
109 | btrfs_set_root_level(item, btrfs_header_level(node)); | |
110 | btrfs_set_root_generation(item, btrfs_header_generation(node)); | |
5d4f98a2 YZ |
111 | } |
112 | ||
d352ac68 CM |
113 | /* |
114 | * copy the data in 'item' into the btree | |
115 | */ | |
e089f05c CM |
116 | int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root |
117 | *root, struct btrfs_key *key, struct btrfs_root_item | |
118 | *item) | |
3768f368 | 119 | { |
0b246afa | 120 | struct btrfs_fs_info *fs_info = root->fs_info; |
5caf2a00 | 121 | struct btrfs_path *path; |
5f39d397 | 122 | struct extent_buffer *l; |
3768f368 CM |
123 | int ret; |
124 | int slot; | |
5f39d397 | 125 | unsigned long ptr; |
0412e58c | 126 | u32 old_len; |
3768f368 | 127 | |
5caf2a00 | 128 | path = btrfs_alloc_path(); |
b45a9d8b JM |
129 | if (!path) |
130 | return -ENOMEM; | |
131 | ||
5caf2a00 | 132 | ret = btrfs_search_slot(trans, root, key, path, 0, 1); |
72bd2323 | 133 | if (ret < 0) |
005d6427 | 134 | goto out; |
d6667462 | 135 | |
7ac1e464 QW |
136 | if (ret > 0) { |
137 | btrfs_crit(fs_info, | |
138 | "unable to find root key (%llu %u %llu) in tree %llu", | |
139 | key->objectid, key->type, key->offset, | |
140 | root->root_key.objectid); | |
141 | ret = -EUCLEAN; | |
142 | btrfs_abort_transaction(trans, ret); | |
143 | goto out; | |
d6667462 CM |
144 | } |
145 | ||
5f39d397 | 146 | l = path->nodes[0]; |
5caf2a00 | 147 | slot = path->slots[0]; |
5f39d397 | 148 | ptr = btrfs_item_ptr_offset(l, slot); |
3212fa14 | 149 | old_len = btrfs_item_size(l, slot); |
8ea05e3a AB |
150 | |
151 | /* | |
152 | * If this is the first time we update the root item which originated | |
153 | * from an older kernel, we need to enlarge the item size to make room | |
154 | * for the added fields. | |
155 | */ | |
156 | if (old_len < sizeof(*item)) { | |
157 | btrfs_release_path(path); | |
158 | ret = btrfs_search_slot(trans, root, key, path, | |
159 | -1, 1); | |
005d6427 | 160 | if (ret < 0) { |
66642832 | 161 | btrfs_abort_transaction(trans, ret); |
005d6427 DS |
162 | goto out; |
163 | } | |
164 | ||
8ea05e3a | 165 | ret = btrfs_del_item(trans, root, path); |
005d6427 | 166 | if (ret < 0) { |
66642832 | 167 | btrfs_abort_transaction(trans, ret); |
005d6427 DS |
168 | goto out; |
169 | } | |
8ea05e3a AB |
170 | btrfs_release_path(path); |
171 | ret = btrfs_insert_empty_item(trans, root, path, | |
172 | key, sizeof(*item)); | |
005d6427 | 173 | if (ret < 0) { |
66642832 | 174 | btrfs_abort_transaction(trans, ret); |
005d6427 DS |
175 | goto out; |
176 | } | |
8ea05e3a AB |
177 | l = path->nodes[0]; |
178 | slot = path->slots[0]; | |
179 | ptr = btrfs_item_ptr_offset(l, slot); | |
180 | } | |
181 | ||
182 | /* | |
183 | * Update generation_v2 so at the next mount we know the new root | |
184 | * fields are valid. | |
185 | */ | |
186 | btrfs_set_root_generation_v2(item, btrfs_root_generation(item)); | |
187 | ||
5f39d397 | 188 | write_extent_buffer(l, item, ptr, sizeof(*item)); |
5caf2a00 | 189 | btrfs_mark_buffer_dirty(path->nodes[0]); |
3768f368 | 190 | out: |
5caf2a00 | 191 | btrfs_free_path(path); |
3768f368 CM |
192 | return ret; |
193 | } | |
194 | ||
d16cb050 | 195 | int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
310712b2 | 196 | const struct btrfs_key *key, struct btrfs_root_item *item) |
3768f368 | 197 | { |
8ea05e3a AB |
198 | /* |
199 | * Make sure generation v1 and v2 match. See update_root for details. | |
200 | */ | |
201 | btrfs_set_root_generation_v2(item, btrfs_root_generation(item)); | |
d16cb050 | 202 | return btrfs_insert_item(trans, root, key, item, sizeof(*item)); |
3768f368 CM |
203 | } |
204 | ||
6bccf3ab | 205 | int btrfs_find_orphan_roots(struct btrfs_fs_info *fs_info) |
76dda93c | 206 | { |
6bccf3ab | 207 | struct btrfs_root *tree_root = fs_info->tree_root; |
76dda93c YZ |
208 | struct extent_buffer *leaf; |
209 | struct btrfs_path *path; | |
210 | struct btrfs_key key; | |
d68fc57b | 211 | struct btrfs_root *root; |
76dda93c YZ |
212 | int err = 0; |
213 | int ret; | |
214 | ||
215 | path = btrfs_alloc_path(); | |
216 | if (!path) | |
217 | return -ENOMEM; | |
218 | ||
219 | key.objectid = BTRFS_ORPHAN_OBJECTID; | |
220 | key.type = BTRFS_ORPHAN_ITEM_KEY; | |
221 | key.offset = 0; | |
222 | ||
223 | while (1) { | |
56e9357a DS |
224 | u64 root_objectid; |
225 | ||
76dda93c YZ |
226 | ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0); |
227 | if (ret < 0) { | |
228 | err = ret; | |
229 | break; | |
230 | } | |
231 | ||
232 | leaf = path->nodes[0]; | |
233 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { | |
234 | ret = btrfs_next_leaf(tree_root, path); | |
235 | if (ret < 0) | |
236 | err = ret; | |
237 | if (ret != 0) | |
238 | break; | |
239 | leaf = path->nodes[0]; | |
240 | } | |
241 | ||
242 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
b3b4aa74 | 243 | btrfs_release_path(path); |
76dda93c YZ |
244 | |
245 | if (key.objectid != BTRFS_ORPHAN_OBJECTID || | |
246 | key.type != BTRFS_ORPHAN_ITEM_KEY) | |
247 | break; | |
248 | ||
56e9357a | 249 | root_objectid = key.offset; |
d68fc57b YZ |
250 | key.offset++; |
251 | ||
56e9357a | 252 | root = btrfs_get_fs_root(fs_info, root_objectid, false); |
886322e8 | 253 | err = PTR_ERR_OR_ZERO(root); |
68a7342c | 254 | if (err && err != -ENOENT) { |
cb517eab | 255 | break; |
68a7342c JB |
256 | } else if (err == -ENOENT) { |
257 | struct btrfs_trans_handle *trans; | |
258 | ||
259 | btrfs_release_path(path); | |
260 | ||
261 | trans = btrfs_join_transaction(tree_root); | |
262 | if (IS_ERR(trans)) { | |
263 | err = PTR_ERR(trans); | |
0b246afa | 264 | btrfs_handle_fs_error(fs_info, err, |
5d163e0e | 265 | "Failed to start trans to delete orphan item"); |
68a7342c JB |
266 | break; |
267 | } | |
268 | err = btrfs_del_orphan_item(trans, tree_root, | |
56e9357a | 269 | root_objectid); |
3a45bb20 | 270 | btrfs_end_transaction(trans); |
68a7342c | 271 | if (err) { |
0b246afa | 272 | btrfs_handle_fs_error(fs_info, err, |
5d163e0e | 273 | "Failed to delete root orphan item"); |
68a7342c JB |
274 | break; |
275 | } | |
276 | continue; | |
cb517eab MX |
277 | } |
278 | ||
e59d18b4 | 279 | WARN_ON(!test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)); |
78c52d9e | 280 | if (btrfs_root_refs(&root->root_item) == 0) { |
b4be6aef JB |
281 | struct btrfs_key drop_key; |
282 | ||
283 | btrfs_disk_key_to_cpu(&drop_key, &root->root_item.drop_progress); | |
284 | /* | |
285 | * If we have a non-zero drop_progress then we know we | |
286 | * made it partly through deleting this snapshot, and | |
287 | * thus we need to make sure we block any balance from | |
288 | * happening until this snapshot is completely dropped. | |
289 | */ | |
290 | if (drop_key.objectid != 0 || drop_key.type != 0 || | |
291 | drop_key.offset != 0) { | |
292 | set_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags); | |
293 | set_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state); | |
294 | } | |
295 | ||
78c52d9e | 296 | set_bit(BTRFS_ROOT_DEAD_TREE, &root->state); |
14927d95 | 297 | btrfs_add_dead_root(root); |
78c52d9e | 298 | } |
00246528 | 299 | btrfs_put_root(root); |
76dda93c YZ |
300 | } |
301 | ||
302 | btrfs_free_path(path); | |
303 | return err; | |
304 | } | |
305 | ||
1cd5447e JM |
306 | /* drop the root item for 'key' from the tree root */ |
307 | int btrfs_del_root(struct btrfs_trans_handle *trans, | |
ab9ce7d4 | 308 | const struct btrfs_key *key) |
3768f368 | 309 | { |
ab9ce7d4 | 310 | struct btrfs_root *root = trans->fs_info->tree_root; |
5caf2a00 | 311 | struct btrfs_path *path; |
3768f368 CM |
312 | int ret; |
313 | ||
5caf2a00 | 314 | path = btrfs_alloc_path(); |
db5b493a TI |
315 | if (!path) |
316 | return -ENOMEM; | |
5caf2a00 | 317 | ret = btrfs_search_slot(trans, root, key, path, -1, 1); |
3768f368 CM |
318 | if (ret < 0) |
319 | goto out; | |
edbd8d4e | 320 | |
3768f368 | 321 | BUG_ON(ret != 0); |
c5739bba | 322 | |
5eda7b5e | 323 | ret = btrfs_del_item(trans, root, path); |
3768f368 | 324 | out: |
5caf2a00 | 325 | btrfs_free_path(path); |
3768f368 CM |
326 | return ret; |
327 | } | |
0660b5af | 328 | |
3ee1c553 LF |
329 | int btrfs_del_root_ref(struct btrfs_trans_handle *trans, u64 root_id, |
330 | u64 ref_id, u64 dirid, u64 *sequence, const char *name, | |
331 | int name_len) | |
4df27c4d | 332 | |
0660b5af | 333 | { |
3ee1c553 | 334 | struct btrfs_root *tree_root = trans->fs_info->tree_root; |
4df27c4d YZ |
335 | struct btrfs_path *path; |
336 | struct btrfs_root_ref *ref; | |
337 | struct extent_buffer *leaf; | |
0660b5af | 338 | struct btrfs_key key; |
4df27c4d YZ |
339 | unsigned long ptr; |
340 | int err = 0; | |
0660b5af | 341 | int ret; |
0660b5af CM |
342 | |
343 | path = btrfs_alloc_path(); | |
4df27c4d YZ |
344 | if (!path) |
345 | return -ENOMEM; | |
0660b5af CM |
346 | |
347 | key.objectid = root_id; | |
4df27c4d | 348 | key.type = BTRFS_ROOT_BACKREF_KEY; |
0660b5af | 349 | key.offset = ref_id; |
4df27c4d | 350 | again: |
0660b5af | 351 | ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); |
47bf225a FM |
352 | if (ret < 0) { |
353 | err = ret; | |
8289ed9f | 354 | goto out; |
47bf225a | 355 | } else if (ret == 0) { |
4df27c4d YZ |
356 | leaf = path->nodes[0]; |
357 | ref = btrfs_item_ptr(leaf, path->slots[0], | |
358 | struct btrfs_root_ref); | |
4df27c4d | 359 | ptr = (unsigned long)(ref + 1); |
423a716c JB |
360 | if ((btrfs_root_ref_dirid(leaf, ref) != dirid) || |
361 | (btrfs_root_ref_name_len(leaf, ref) != name_len) || | |
362 | memcmp_extent_buffer(leaf, name, ptr, name_len)) { | |
363 | err = -ENOENT; | |
364 | goto out; | |
365 | } | |
4df27c4d YZ |
366 | *sequence = btrfs_root_ref_sequence(leaf, ref); |
367 | ||
368 | ret = btrfs_del_item(trans, tree_root, path); | |
65a246c5 TI |
369 | if (ret) { |
370 | err = ret; | |
371 | goto out; | |
372 | } | |
4df27c4d YZ |
373 | } else |
374 | err = -ENOENT; | |
375 | ||
376 | if (key.type == BTRFS_ROOT_BACKREF_KEY) { | |
b3b4aa74 | 377 | btrfs_release_path(path); |
4df27c4d YZ |
378 | key.objectid = ref_id; |
379 | key.type = BTRFS_ROOT_REF_KEY; | |
380 | key.offset = root_id; | |
381 | goto again; | |
382 | } | |
0660b5af | 383 | |
65a246c5 | 384 | out: |
0660b5af | 385 | btrfs_free_path(path); |
4df27c4d | 386 | return err; |
0660b5af CM |
387 | } |
388 | ||
389 | /* | |
390 | * add a btrfs_root_ref item. type is either BTRFS_ROOT_REF_KEY | |
391 | * or BTRFS_ROOT_BACKREF_KEY. | |
392 | * | |
393 | * The dirid, sequence, name and name_len refer to the directory entry | |
394 | * that is referencing the root. | |
395 | * | |
396 | * For a forward ref, the root_id is the id of the tree referencing | |
397 | * the root and ref_id is the id of the subvol or snapshot. | |
398 | * | |
399 | * For a back ref the root_id is the id of the subvol or snapshot and | |
400 | * ref_id is the id of the tree referencing it. | |
79787eaa JM |
401 | * |
402 | * Will return 0, -ENOMEM, or anything from the CoW path | |
0660b5af | 403 | */ |
6025c19f LF |
404 | int btrfs_add_root_ref(struct btrfs_trans_handle *trans, u64 root_id, |
405 | u64 ref_id, u64 dirid, u64 sequence, const char *name, | |
406 | int name_len) | |
0660b5af | 407 | { |
6025c19f | 408 | struct btrfs_root *tree_root = trans->fs_info->tree_root; |
0660b5af CM |
409 | struct btrfs_key key; |
410 | int ret; | |
411 | struct btrfs_path *path; | |
412 | struct btrfs_root_ref *ref; | |
413 | struct extent_buffer *leaf; | |
414 | unsigned long ptr; | |
415 | ||
0660b5af | 416 | path = btrfs_alloc_path(); |
4df27c4d YZ |
417 | if (!path) |
418 | return -ENOMEM; | |
0660b5af CM |
419 | |
420 | key.objectid = root_id; | |
4df27c4d | 421 | key.type = BTRFS_ROOT_BACKREF_KEY; |
0660b5af | 422 | key.offset = ref_id; |
4df27c4d | 423 | again: |
0660b5af CM |
424 | ret = btrfs_insert_empty_item(trans, tree_root, path, &key, |
425 | sizeof(*ref) + name_len); | |
79787eaa | 426 | if (ret) { |
66642832 | 427 | btrfs_abort_transaction(trans, ret); |
79787eaa JM |
428 | btrfs_free_path(path); |
429 | return ret; | |
430 | } | |
0660b5af CM |
431 | |
432 | leaf = path->nodes[0]; | |
433 | ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); | |
434 | btrfs_set_root_ref_dirid(leaf, ref, dirid); | |
435 | btrfs_set_root_ref_sequence(leaf, ref, sequence); | |
436 | btrfs_set_root_ref_name_len(leaf, ref, name_len); | |
437 | ptr = (unsigned long)(ref + 1); | |
438 | write_extent_buffer(leaf, name, ptr, name_len); | |
439 | btrfs_mark_buffer_dirty(leaf); | |
440 | ||
4df27c4d | 441 | if (key.type == BTRFS_ROOT_BACKREF_KEY) { |
b3b4aa74 | 442 | btrfs_release_path(path); |
4df27c4d YZ |
443 | key.objectid = ref_id; |
444 | key.type = BTRFS_ROOT_REF_KEY; | |
445 | key.offset = root_id; | |
446 | goto again; | |
447 | } | |
448 | ||
0660b5af | 449 | btrfs_free_path(path); |
4df27c4d | 450 | return 0; |
0660b5af | 451 | } |
08fe4db1 LZ |
452 | |
453 | /* | |
454 | * Old btrfs forgets to init root_item->flags and root_item->byte_limit | |
455 | * for subvolumes. To work around this problem, we steal a bit from | |
456 | * root_item->inode_item->flags, and use it to indicate if those fields | |
457 | * have been properly initialized. | |
458 | */ | |
459 | void btrfs_check_and_init_root_item(struct btrfs_root_item *root_item) | |
460 | { | |
3cae210f | 461 | u64 inode_flags = btrfs_stack_inode_flags(&root_item->inode); |
08fe4db1 LZ |
462 | |
463 | if (!(inode_flags & BTRFS_INODE_ROOT_ITEM_INIT)) { | |
464 | inode_flags |= BTRFS_INODE_ROOT_ITEM_INIT; | |
3cae210f QW |
465 | btrfs_set_stack_inode_flags(&root_item->inode, inode_flags); |
466 | btrfs_set_root_flags(root_item, 0); | |
467 | btrfs_set_root_limit(root_item, 0); | |
08fe4db1 LZ |
468 | } |
469 | } | |
8ea05e3a AB |
470 | |
471 | void btrfs_update_root_times(struct btrfs_trans_handle *trans, | |
472 | struct btrfs_root *root) | |
473 | { | |
474 | struct btrfs_root_item *item = &root->root_item; | |
95582b00 | 475 | struct timespec64 ct; |
8ea05e3a | 476 | |
95582b00 | 477 | ktime_get_real_ts64(&ct); |
5f3ab90a | 478 | spin_lock(&root->root_item_lock); |
3cae210f QW |
479 | btrfs_set_root_ctransid(item, trans->transid); |
480 | btrfs_set_stack_timespec_sec(&item->ctime, ct.tv_sec); | |
481 | btrfs_set_stack_timespec_nsec(&item->ctime, ct.tv_nsec); | |
5f3ab90a | 482 | spin_unlock(&root->root_item_lock); |
8ea05e3a | 483 | } |
28a32d2b JB |
484 | |
485 | /* | |
486 | * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation | |
487 | * root: the root of the parent directory | |
488 | * rsv: block reservation | |
489 | * items: the number of items that we need do reservation | |
490 | * use_global_rsv: allow fallback to the global block reservation | |
491 | * | |
492 | * This function is used to reserve the space for snapshot/subvolume | |
493 | * creation and deletion. Those operations are different with the | |
494 | * common file/directory operations, they change two fs/file trees | |
495 | * and root tree, the number of items that the qgroup reserves is | |
496 | * different with the free space reservation. So we can not use | |
497 | * the space reservation mechanism in start_transaction(). | |
498 | */ | |
499 | int btrfs_subvolume_reserve_metadata(struct btrfs_root *root, | |
500 | struct btrfs_block_rsv *rsv, int items, | |
501 | bool use_global_rsv) | |
502 | { | |
503 | u64 qgroup_num_bytes = 0; | |
504 | u64 num_bytes; | |
505 | int ret; | |
506 | struct btrfs_fs_info *fs_info = root->fs_info; | |
507 | struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; | |
508 | ||
509 | if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) { | |
510 | /* One for parent inode, two for dir entries */ | |
511 | qgroup_num_bytes = 3 * fs_info->nodesize; | |
512 | ret = btrfs_qgroup_reserve_meta_prealloc(root, | |
d4135134 FM |
513 | qgroup_num_bytes, true, |
514 | false); | |
28a32d2b JB |
515 | if (ret) |
516 | return ret; | |
517 | } | |
518 | ||
2bd36e7b | 519 | num_bytes = btrfs_calc_insert_metadata_size(fs_info, items); |
28a32d2b JB |
520 | rsv->space_info = btrfs_find_space_info(fs_info, |
521 | BTRFS_BLOCK_GROUP_METADATA); | |
9270501c | 522 | ret = btrfs_block_rsv_add(fs_info, rsv, num_bytes, |
28a32d2b JB |
523 | BTRFS_RESERVE_FLUSH_ALL); |
524 | ||
525 | if (ret == -ENOSPC && use_global_rsv) | |
526 | ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, true); | |
527 | ||
528 | if (ret && qgroup_num_bytes) | |
529 | btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes); | |
530 | ||
e85fde51 QW |
531 | if (!ret) { |
532 | spin_lock(&rsv->lock); | |
533 | rsv->qgroup_rsv_reserved += qgroup_num_bytes; | |
534 | spin_unlock(&rsv->lock); | |
535 | } | |
28a32d2b JB |
536 | return ret; |
537 | } | |
538 | ||
e85fde51 | 539 | void btrfs_subvolume_release_metadata(struct btrfs_root *root, |
28a32d2b JB |
540 | struct btrfs_block_rsv *rsv) |
541 | { | |
e85fde51 QW |
542 | struct btrfs_fs_info *fs_info = root->fs_info; |
543 | u64 qgroup_to_release; | |
544 | ||
545 | btrfs_block_rsv_release(fs_info, rsv, (u64)-1, &qgroup_to_release); | |
546 | btrfs_qgroup_convert_reserved_meta(root, qgroup_to_release); | |
28a32d2b | 547 | } |