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Merge tag 'xtensa-20230905' of https://github.com/jcmvbkbc/linux-xtensa
[thirdparty/linux.git] / fs / btrfs / sysfs.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/sched.h>
7 #include <linux/sched/mm.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/bug.h>
12 #include <linux/list.h>
13 #include <crypto/hash.h>
14 #include "messages.h"
15 #include "ctree.h"
16 #include "discard.h"
17 #include "disk-io.h"
18 #include "send.h"
19 #include "transaction.h"
20 #include "sysfs.h"
21 #include "volumes.h"
22 #include "space-info.h"
23 #include "block-group.h"
24 #include "qgroup.h"
25 #include "misc.h"
26 #include "fs.h"
27 #include "accessors.h"
28
29 /*
30 * Structure name Path
31 * --------------------------------------------------------------------------
32 * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features
33 * btrfs_supported_feature_attrs /sys/fs/btrfs/features and
34 * /sys/fs/btrfs/<uuid>/features
35 * btrfs_attrs /sys/fs/btrfs/<uuid>
36 * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid>
37 * allocation_attrs /sys/fs/btrfs/<uuid>/allocation
38 * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>
39 * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>
40 * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>
41 * discard_attrs /sys/fs/btrfs/<uuid>/discard
42 *
43 * When built with BTRFS_CONFIG_DEBUG:
44 *
45 * btrfs_debug_feature_attrs /sys/fs/btrfs/debug
46 * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug
47 */
48
49 struct btrfs_feature_attr {
50 struct kobj_attribute kobj_attr;
51 enum btrfs_feature_set feature_set;
52 u64 feature_bit;
53 };
54
55 /* For raid type sysfs entries */
56 struct raid_kobject {
57 u64 flags;
58 struct kobject kobj;
59 };
60
61 #define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
62 { \
63 .attr = { .name = __stringify(_name), .mode = _mode }, \
64 .show = _show, \
65 .store = _store, \
66 }
67
68 #define BTRFS_ATTR_W(_prefix, _name, _store) \
69 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
70 __INIT_KOBJ_ATTR(_name, 0200, NULL, _store)
71
72 #define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
73 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
74 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
75
76 #define BTRFS_ATTR(_prefix, _name, _show) \
77 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
78 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
79
80 #define BTRFS_ATTR_PTR(_prefix, _name) \
81 (&btrfs_attr_##_prefix##_##_name.attr)
82
83 #define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
84 static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
85 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
86 btrfs_feature_attr_show, \
87 btrfs_feature_attr_store), \
88 .feature_set = _feature_set, \
89 .feature_bit = _feature_prefix ##_## _feature_bit, \
90 }
91 #define BTRFS_FEAT_ATTR_PTR(_name) \
92 (&btrfs_attr_features_##_name.kobj_attr.attr)
93
94 #define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
95 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
96 #define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
97 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
98 #define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
99 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
100
101 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
102 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
103 static struct kobject *get_btrfs_kobj(struct kobject *kobj);
104
105 static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
106 {
107 return container_of(a, struct btrfs_feature_attr, kobj_attr);
108 }
109
110 static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
111 {
112 return container_of(attr, struct kobj_attribute, attr);
113 }
114
115 static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
116 struct attribute *attr)
117 {
118 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
119 }
120
121 static u64 get_features(struct btrfs_fs_info *fs_info,
122 enum btrfs_feature_set set)
123 {
124 struct btrfs_super_block *disk_super = fs_info->super_copy;
125 if (set == FEAT_COMPAT)
126 return btrfs_super_compat_flags(disk_super);
127 else if (set == FEAT_COMPAT_RO)
128 return btrfs_super_compat_ro_flags(disk_super);
129 else
130 return btrfs_super_incompat_flags(disk_super);
131 }
132
133 static void set_features(struct btrfs_fs_info *fs_info,
134 enum btrfs_feature_set set, u64 features)
135 {
136 struct btrfs_super_block *disk_super = fs_info->super_copy;
137 if (set == FEAT_COMPAT)
138 btrfs_set_super_compat_flags(disk_super, features);
139 else if (set == FEAT_COMPAT_RO)
140 btrfs_set_super_compat_ro_flags(disk_super, features);
141 else
142 btrfs_set_super_incompat_flags(disk_super, features);
143 }
144
145 static int can_modify_feature(struct btrfs_feature_attr *fa)
146 {
147 int val = 0;
148 u64 set, clear;
149 switch (fa->feature_set) {
150 case FEAT_COMPAT:
151 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
152 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
153 break;
154 case FEAT_COMPAT_RO:
155 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
156 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
157 break;
158 case FEAT_INCOMPAT:
159 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
160 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
161 break;
162 default:
163 pr_warn("btrfs: sysfs: unknown feature set %d\n",
164 fa->feature_set);
165 return 0;
166 }
167
168 if (set & fa->feature_bit)
169 val |= 1;
170 if (clear & fa->feature_bit)
171 val |= 2;
172
173 return val;
174 }
175
176 static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
177 struct kobj_attribute *a, char *buf)
178 {
179 int val = 0;
180 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
181 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
182 if (fs_info) {
183 u64 features = get_features(fs_info, fa->feature_set);
184 if (features & fa->feature_bit)
185 val = 1;
186 } else
187 val = can_modify_feature(fa);
188
189 return sysfs_emit(buf, "%d\n", val);
190 }
191
192 static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
193 struct kobj_attribute *a,
194 const char *buf, size_t count)
195 {
196 struct btrfs_fs_info *fs_info;
197 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
198 u64 features, set, clear;
199 unsigned long val;
200 int ret;
201
202 fs_info = to_fs_info(kobj);
203 if (!fs_info)
204 return -EPERM;
205
206 if (sb_rdonly(fs_info->sb))
207 return -EROFS;
208
209 ret = kstrtoul(skip_spaces(buf), 0, &val);
210 if (ret)
211 return ret;
212
213 if (fa->feature_set == FEAT_COMPAT) {
214 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
215 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
216 } else if (fa->feature_set == FEAT_COMPAT_RO) {
217 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
218 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
219 } else {
220 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
221 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
222 }
223
224 features = get_features(fs_info, fa->feature_set);
225
226 /* Nothing to do */
227 if ((val && (features & fa->feature_bit)) ||
228 (!val && !(features & fa->feature_bit)))
229 return count;
230
231 if ((val && !(set & fa->feature_bit)) ||
232 (!val && !(clear & fa->feature_bit))) {
233 btrfs_info(fs_info,
234 "%sabling feature %s on mounted fs is not supported.",
235 val ? "En" : "Dis", fa->kobj_attr.attr.name);
236 return -EPERM;
237 }
238
239 btrfs_info(fs_info, "%s %s feature flag",
240 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
241
242 spin_lock(&fs_info->super_lock);
243 features = get_features(fs_info, fa->feature_set);
244 if (val)
245 features |= fa->feature_bit;
246 else
247 features &= ~fa->feature_bit;
248 set_features(fs_info, fa->feature_set, features);
249 spin_unlock(&fs_info->super_lock);
250
251 /*
252 * We don't want to do full transaction commit from inside sysfs
253 */
254 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
255 wake_up_process(fs_info->transaction_kthread);
256
257 return count;
258 }
259
260 static umode_t btrfs_feature_visible(struct kobject *kobj,
261 struct attribute *attr, int unused)
262 {
263 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
264 umode_t mode = attr->mode;
265
266 if (fs_info) {
267 struct btrfs_feature_attr *fa;
268 u64 features;
269
270 fa = attr_to_btrfs_feature_attr(attr);
271 features = get_features(fs_info, fa->feature_set);
272
273 if (can_modify_feature(fa))
274 mode |= S_IWUSR;
275 else if (!(features & fa->feature_bit))
276 mode = 0;
277 }
278
279 return mode;
280 }
281
282 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
283 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
284 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
285 BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
286 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
287 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
288 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
289 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
290 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
291 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
292 BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE);
293 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
294 #ifdef CONFIG_BLK_DEV_ZONED
295 BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
296 #endif
297 #ifdef CONFIG_BTRFS_DEBUG
298 /* Remove once support for extent tree v2 is feature complete */
299 BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2);
300 #endif
301 #ifdef CONFIG_FS_VERITY
302 BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
303 #endif
304
305 /*
306 * Features which depend on feature bits and may differ between each fs.
307 *
308 * /sys/fs/btrfs/features - all available features implemented by this version
309 * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or
310 * can be changed on a mounted filesystem.
311 */
312 static struct attribute *btrfs_supported_feature_attrs[] = {
313 BTRFS_FEAT_ATTR_PTR(default_subvol),
314 BTRFS_FEAT_ATTR_PTR(mixed_groups),
315 BTRFS_FEAT_ATTR_PTR(compress_lzo),
316 BTRFS_FEAT_ATTR_PTR(compress_zstd),
317 BTRFS_FEAT_ATTR_PTR(extended_iref),
318 BTRFS_FEAT_ATTR_PTR(raid56),
319 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
320 BTRFS_FEAT_ATTR_PTR(no_holes),
321 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
322 BTRFS_FEAT_ATTR_PTR(free_space_tree),
323 BTRFS_FEAT_ATTR_PTR(raid1c34),
324 BTRFS_FEAT_ATTR_PTR(block_group_tree),
325 #ifdef CONFIG_BLK_DEV_ZONED
326 BTRFS_FEAT_ATTR_PTR(zoned),
327 #endif
328 #ifdef CONFIG_BTRFS_DEBUG
329 BTRFS_FEAT_ATTR_PTR(extent_tree_v2),
330 #endif
331 #ifdef CONFIG_FS_VERITY
332 BTRFS_FEAT_ATTR_PTR(verity),
333 #endif
334 NULL
335 };
336
337 static const struct attribute_group btrfs_feature_attr_group = {
338 .name = "features",
339 .is_visible = btrfs_feature_visible,
340 .attrs = btrfs_supported_feature_attrs,
341 };
342
343 static ssize_t rmdir_subvol_show(struct kobject *kobj,
344 struct kobj_attribute *ka, char *buf)
345 {
346 return sysfs_emit(buf, "0\n");
347 }
348 BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
349
350 static ssize_t supported_checksums_show(struct kobject *kobj,
351 struct kobj_attribute *a, char *buf)
352 {
353 ssize_t ret = 0;
354 int i;
355
356 for (i = 0; i < btrfs_get_num_csums(); i++) {
357 /*
358 * This "trick" only works as long as 'enum btrfs_csum_type' has
359 * no holes in it
360 */
361 ret += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "),
362 btrfs_super_csum_name(i));
363
364 }
365
366 ret += sysfs_emit_at(buf, ret, "\n");
367 return ret;
368 }
369 BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
370
371 static ssize_t send_stream_version_show(struct kobject *kobj,
372 struct kobj_attribute *ka, char *buf)
373 {
374 return sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION);
375 }
376 BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
377
378 static const char *rescue_opts[] = {
379 "usebackuproot",
380 "nologreplay",
381 "ignorebadroots",
382 "ignoredatacsums",
383 "all",
384 };
385
386 static ssize_t supported_rescue_options_show(struct kobject *kobj,
387 struct kobj_attribute *a,
388 char *buf)
389 {
390 ssize_t ret = 0;
391 int i;
392
393 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
394 ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]);
395 ret += sysfs_emit_at(buf, ret, "\n");
396 return ret;
397 }
398 BTRFS_ATTR(static_feature, supported_rescue_options,
399 supported_rescue_options_show);
400
401 static ssize_t supported_sectorsizes_show(struct kobject *kobj,
402 struct kobj_attribute *a,
403 char *buf)
404 {
405 ssize_t ret = 0;
406
407 /* An artificial limit to only support 4K and PAGE_SIZE */
408 if (PAGE_SIZE > SZ_4K)
409 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K);
410 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE);
411
412 return ret;
413 }
414 BTRFS_ATTR(static_feature, supported_sectorsizes,
415 supported_sectorsizes_show);
416
417 static ssize_t acl_show(struct kobject *kobj, struct kobj_attribute *a, char *buf)
418 {
419 return sysfs_emit(buf, "%d\n", !!IS_ENABLED(CONFIG_BTRFS_FS_POSIX_ACL));
420 }
421 BTRFS_ATTR(static_feature, acl, acl_show);
422
423 /*
424 * Features which only depend on kernel version.
425 *
426 * These are listed in /sys/fs/btrfs/features along with
427 * btrfs_supported_feature_attrs.
428 */
429 static struct attribute *btrfs_supported_static_feature_attrs[] = {
430 BTRFS_ATTR_PTR(static_feature, acl),
431 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
432 BTRFS_ATTR_PTR(static_feature, supported_checksums),
433 BTRFS_ATTR_PTR(static_feature, send_stream_version),
434 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
435 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
436 NULL
437 };
438
439 static const struct attribute_group btrfs_static_feature_attr_group = {
440 .name = "features",
441 .attrs = btrfs_supported_static_feature_attrs,
442 };
443
444 /*
445 * Discard statistics and tunables
446 */
447 #define discard_to_fs_info(_kobj) to_fs_info(get_btrfs_kobj(_kobj))
448
449 static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
450 struct kobj_attribute *a,
451 char *buf)
452 {
453 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
454
455 return sysfs_emit(buf, "%lld\n",
456 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
457 }
458 BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
459
460 static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
461 struct kobj_attribute *a,
462 char *buf)
463 {
464 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
465
466 return sysfs_emit(buf, "%d\n",
467 atomic_read(&fs_info->discard_ctl.discardable_extents));
468 }
469 BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
470
471 static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
472 struct kobj_attribute *a,
473 char *buf)
474 {
475 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
476
477 return sysfs_emit(buf, "%llu\n",
478 fs_info->discard_ctl.discard_bitmap_bytes);
479 }
480 BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
481
482 static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
483 struct kobj_attribute *a,
484 char *buf)
485 {
486 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
487
488 return sysfs_emit(buf, "%lld\n",
489 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
490 }
491 BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
492
493 static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
494 struct kobj_attribute *a,
495 char *buf)
496 {
497 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
498
499 return sysfs_emit(buf, "%llu\n",
500 fs_info->discard_ctl.discard_extent_bytes);
501 }
502 BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
503
504 static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
505 struct kobj_attribute *a,
506 char *buf)
507 {
508 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
509
510 return sysfs_emit(buf, "%u\n",
511 READ_ONCE(fs_info->discard_ctl.iops_limit));
512 }
513
514 static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
515 struct kobj_attribute *a,
516 const char *buf, size_t len)
517 {
518 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
519 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
520 u32 iops_limit;
521 int ret;
522
523 ret = kstrtou32(buf, 10, &iops_limit);
524 if (ret)
525 return -EINVAL;
526
527 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
528 btrfs_discard_calc_delay(discard_ctl);
529 btrfs_discard_schedule_work(discard_ctl, true);
530 return len;
531 }
532 BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
533 btrfs_discard_iops_limit_store);
534
535 static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
536 struct kobj_attribute *a,
537 char *buf)
538 {
539 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
540
541 return sysfs_emit(buf, "%u\n",
542 READ_ONCE(fs_info->discard_ctl.kbps_limit));
543 }
544
545 static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
546 struct kobj_attribute *a,
547 const char *buf, size_t len)
548 {
549 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
550 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
551 u32 kbps_limit;
552 int ret;
553
554 ret = kstrtou32(buf, 10, &kbps_limit);
555 if (ret)
556 return -EINVAL;
557
558 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
559 btrfs_discard_schedule_work(discard_ctl, true);
560 return len;
561 }
562 BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
563 btrfs_discard_kbps_limit_store);
564
565 static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
566 struct kobj_attribute *a,
567 char *buf)
568 {
569 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
570
571 return sysfs_emit(buf, "%llu\n",
572 READ_ONCE(fs_info->discard_ctl.max_discard_size));
573 }
574
575 static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
576 struct kobj_attribute *a,
577 const char *buf, size_t len)
578 {
579 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
580 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
581 u64 max_discard_size;
582 int ret;
583
584 ret = kstrtou64(buf, 10, &max_discard_size);
585 if (ret)
586 return -EINVAL;
587
588 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
589
590 return len;
591 }
592 BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
593 btrfs_discard_max_discard_size_store);
594
595 /*
596 * Per-filesystem stats for discard (when mounted with discard=async).
597 *
598 * Path: /sys/fs/btrfs/<uuid>/discard/
599 */
600 static const struct attribute *discard_attrs[] = {
601 BTRFS_ATTR_PTR(discard, discardable_bytes),
602 BTRFS_ATTR_PTR(discard, discardable_extents),
603 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
604 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
605 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
606 BTRFS_ATTR_PTR(discard, iops_limit),
607 BTRFS_ATTR_PTR(discard, kbps_limit),
608 BTRFS_ATTR_PTR(discard, max_discard_size),
609 NULL,
610 };
611
612 #ifdef CONFIG_BTRFS_DEBUG
613
614 /*
615 * Per-filesystem runtime debugging exported via sysfs.
616 *
617 * Path: /sys/fs/btrfs/UUID/debug/
618 */
619 static const struct attribute *btrfs_debug_mount_attrs[] = {
620 NULL,
621 };
622
623 /*
624 * Runtime debugging exported via sysfs, applies to all mounted filesystems.
625 *
626 * Path: /sys/fs/btrfs/debug
627 */
628 static struct attribute *btrfs_debug_feature_attrs[] = {
629 NULL
630 };
631
632 static const struct attribute_group btrfs_debug_feature_attr_group = {
633 .name = "debug",
634 .attrs = btrfs_debug_feature_attrs,
635 };
636
637 #endif
638
639 static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
640 {
641 u64 val;
642 if (lock)
643 spin_lock(lock);
644 val = *value_ptr;
645 if (lock)
646 spin_unlock(lock);
647 return sysfs_emit(buf, "%llu\n", val);
648 }
649
650 static ssize_t global_rsv_size_show(struct kobject *kobj,
651 struct kobj_attribute *ka, char *buf)
652 {
653 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
654 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
655 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
656 }
657 BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
658
659 static ssize_t global_rsv_reserved_show(struct kobject *kobj,
660 struct kobj_attribute *a, char *buf)
661 {
662 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
663 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
664 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
665 }
666 BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
667
668 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
669 #define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
670
671 static ssize_t raid_bytes_show(struct kobject *kobj,
672 struct kobj_attribute *attr, char *buf);
673 BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
674 BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
675
676 static ssize_t raid_bytes_show(struct kobject *kobj,
677 struct kobj_attribute *attr, char *buf)
678
679 {
680 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
681 struct btrfs_block_group *block_group;
682 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
683 u64 val = 0;
684
685 down_read(&sinfo->groups_sem);
686 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
687 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
688 val += block_group->length;
689 else
690 val += block_group->used;
691 }
692 up_read(&sinfo->groups_sem);
693 return sysfs_emit(buf, "%llu\n", val);
694 }
695
696 /*
697 * Allocation information about block group profiles.
698 *
699 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/
700 */
701 static struct attribute *raid_attrs[] = {
702 BTRFS_ATTR_PTR(raid, total_bytes),
703 BTRFS_ATTR_PTR(raid, used_bytes),
704 NULL
705 };
706 ATTRIBUTE_GROUPS(raid);
707
708 static void release_raid_kobj(struct kobject *kobj)
709 {
710 kfree(to_raid_kobj(kobj));
711 }
712
713 static const struct kobj_type btrfs_raid_ktype = {
714 .sysfs_ops = &kobj_sysfs_ops,
715 .release = release_raid_kobj,
716 .default_groups = raid_groups,
717 };
718
719 #define SPACE_INFO_ATTR(field) \
720 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
721 struct kobj_attribute *a, \
722 char *buf) \
723 { \
724 struct btrfs_space_info *sinfo = to_space_info(kobj); \
725 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
726 } \
727 BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
728
729 static ssize_t btrfs_chunk_size_show(struct kobject *kobj,
730 struct kobj_attribute *a, char *buf)
731 {
732 struct btrfs_space_info *sinfo = to_space_info(kobj);
733
734 return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size));
735 }
736
737 /*
738 * Store new chunk size in space info. Can be called on a read-only filesystem.
739 *
740 * If the new chunk size value is larger than 10% of free space it is reduced
741 * to match that limit. Alignment must be to 256M and the system chunk size
742 * cannot be set.
743 */
744 static ssize_t btrfs_chunk_size_store(struct kobject *kobj,
745 struct kobj_attribute *a,
746 const char *buf, size_t len)
747 {
748 struct btrfs_space_info *space_info = to_space_info(kobj);
749 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
750 char *retptr;
751 u64 val;
752
753 if (!capable(CAP_SYS_ADMIN))
754 return -EPERM;
755
756 if (!fs_info->fs_devices)
757 return -EINVAL;
758
759 if (btrfs_is_zoned(fs_info))
760 return -EINVAL;
761
762 /* System block type must not be changed. */
763 if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
764 return -EPERM;
765
766 val = memparse(buf, &retptr);
767 /* There could be trailing '\n', also catch any typos after the value */
768 retptr = skip_spaces(retptr);
769 if (*retptr != 0 || val == 0)
770 return -EINVAL;
771
772 val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE);
773
774 /* Limit stripe size to 10% of available space. */
775 val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val);
776
777 /* Must be multiple of 256M. */
778 val &= ~((u64)SZ_256M - 1);
779
780 /* Must be at least 256M. */
781 if (val < SZ_256M)
782 return -EINVAL;
783
784 btrfs_update_space_info_chunk_size(space_info, val);
785
786 return len;
787 }
788
789 static ssize_t btrfs_size_classes_show(struct kobject *kobj,
790 struct kobj_attribute *a, char *buf)
791 {
792 struct btrfs_space_info *sinfo = to_space_info(kobj);
793 struct btrfs_block_group *bg;
794 u32 none = 0;
795 u32 small = 0;
796 u32 medium = 0;
797 u32 large = 0;
798
799 for (int i = 0; i < BTRFS_NR_RAID_TYPES; ++i) {
800 down_read(&sinfo->groups_sem);
801 list_for_each_entry(bg, &sinfo->block_groups[i], list) {
802 if (!btrfs_block_group_should_use_size_class(bg))
803 continue;
804 switch (bg->size_class) {
805 case BTRFS_BG_SZ_NONE:
806 none++;
807 break;
808 case BTRFS_BG_SZ_SMALL:
809 small++;
810 break;
811 case BTRFS_BG_SZ_MEDIUM:
812 medium++;
813 break;
814 case BTRFS_BG_SZ_LARGE:
815 large++;
816 break;
817 }
818 }
819 up_read(&sinfo->groups_sem);
820 }
821 return sysfs_emit(buf, "none %u\n"
822 "small %u\n"
823 "medium %u\n"
824 "large %u\n",
825 none, small, medium, large);
826 }
827
828 #ifdef CONFIG_BTRFS_DEBUG
829 /*
830 * Request chunk allocation with current chunk size.
831 */
832 static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj,
833 struct kobj_attribute *a,
834 const char *buf, size_t len)
835 {
836 struct btrfs_space_info *space_info = to_space_info(kobj);
837 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
838 struct btrfs_trans_handle *trans;
839 bool val;
840 int ret;
841
842 if (!capable(CAP_SYS_ADMIN))
843 return -EPERM;
844
845 if (sb_rdonly(fs_info->sb))
846 return -EROFS;
847
848 ret = kstrtobool(buf, &val);
849 if (ret)
850 return ret;
851
852 if (!val)
853 return -EINVAL;
854
855 /*
856 * This is unsafe to be called from sysfs context and may cause
857 * unexpected problems.
858 */
859 trans = btrfs_start_transaction(fs_info->tree_root, 0);
860 if (IS_ERR(trans))
861 return PTR_ERR(trans);
862 ret = btrfs_force_chunk_alloc(trans, space_info->flags);
863 btrfs_end_transaction(trans);
864
865 if (ret == 1)
866 return len;
867
868 return -ENOSPC;
869 }
870 BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store);
871
872 #endif
873
874 SPACE_INFO_ATTR(flags);
875 SPACE_INFO_ATTR(total_bytes);
876 SPACE_INFO_ATTR(bytes_used);
877 SPACE_INFO_ATTR(bytes_pinned);
878 SPACE_INFO_ATTR(bytes_reserved);
879 SPACE_INFO_ATTR(bytes_may_use);
880 SPACE_INFO_ATTR(bytes_readonly);
881 SPACE_INFO_ATTR(bytes_zone_unusable);
882 SPACE_INFO_ATTR(disk_used);
883 SPACE_INFO_ATTR(disk_total);
884 BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store);
885 BTRFS_ATTR(space_info, size_classes, btrfs_size_classes_show);
886
887 static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj,
888 struct kobj_attribute *a,
889 char *buf)
890 {
891 struct btrfs_space_info *space_info = to_space_info(kobj);
892
893 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->bg_reclaim_threshold));
894 }
895
896 static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj,
897 struct kobj_attribute *a,
898 const char *buf, size_t len)
899 {
900 struct btrfs_space_info *space_info = to_space_info(kobj);
901 int thresh;
902 int ret;
903
904 ret = kstrtoint(buf, 10, &thresh);
905 if (ret)
906 return ret;
907
908 if (thresh < 0 || thresh > 100)
909 return -EINVAL;
910
911 WRITE_ONCE(space_info->bg_reclaim_threshold, thresh);
912
913 return len;
914 }
915
916 BTRFS_ATTR_RW(space_info, bg_reclaim_threshold,
917 btrfs_sinfo_bg_reclaim_threshold_show,
918 btrfs_sinfo_bg_reclaim_threshold_store);
919
920 /*
921 * Allocation information about block group types.
922 *
923 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/
924 */
925 static struct attribute *space_info_attrs[] = {
926 BTRFS_ATTR_PTR(space_info, flags),
927 BTRFS_ATTR_PTR(space_info, total_bytes),
928 BTRFS_ATTR_PTR(space_info, bytes_used),
929 BTRFS_ATTR_PTR(space_info, bytes_pinned),
930 BTRFS_ATTR_PTR(space_info, bytes_reserved),
931 BTRFS_ATTR_PTR(space_info, bytes_may_use),
932 BTRFS_ATTR_PTR(space_info, bytes_readonly),
933 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
934 BTRFS_ATTR_PTR(space_info, disk_used),
935 BTRFS_ATTR_PTR(space_info, disk_total),
936 BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold),
937 BTRFS_ATTR_PTR(space_info, chunk_size),
938 BTRFS_ATTR_PTR(space_info, size_classes),
939 #ifdef CONFIG_BTRFS_DEBUG
940 BTRFS_ATTR_PTR(space_info, force_chunk_alloc),
941 #endif
942 NULL,
943 };
944 ATTRIBUTE_GROUPS(space_info);
945
946 static void space_info_release(struct kobject *kobj)
947 {
948 struct btrfs_space_info *sinfo = to_space_info(kobj);
949 kfree(sinfo);
950 }
951
952 static const struct kobj_type space_info_ktype = {
953 .sysfs_ops = &kobj_sysfs_ops,
954 .release = space_info_release,
955 .default_groups = space_info_groups,
956 };
957
958 /*
959 * Allocation information about block groups.
960 *
961 * Path: /sys/fs/btrfs/<uuid>/allocation/
962 */
963 static const struct attribute *allocation_attrs[] = {
964 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
965 BTRFS_ATTR_PTR(allocation, global_rsv_size),
966 NULL,
967 };
968
969 static ssize_t btrfs_label_show(struct kobject *kobj,
970 struct kobj_attribute *a, char *buf)
971 {
972 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
973 char *label = fs_info->super_copy->label;
974 ssize_t ret;
975
976 spin_lock(&fs_info->super_lock);
977 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label);
978 spin_unlock(&fs_info->super_lock);
979
980 return ret;
981 }
982
983 static ssize_t btrfs_label_store(struct kobject *kobj,
984 struct kobj_attribute *a,
985 const char *buf, size_t len)
986 {
987 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
988 size_t p_len;
989
990 if (!fs_info)
991 return -EPERM;
992
993 if (sb_rdonly(fs_info->sb))
994 return -EROFS;
995
996 /*
997 * p_len is the len until the first occurrence of either
998 * '\n' or '\0'
999 */
1000 p_len = strcspn(buf, "\n");
1001
1002 if (p_len >= BTRFS_LABEL_SIZE)
1003 return -EINVAL;
1004
1005 spin_lock(&fs_info->super_lock);
1006 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
1007 memcpy(fs_info->super_copy->label, buf, p_len);
1008 spin_unlock(&fs_info->super_lock);
1009
1010 /*
1011 * We don't want to do full transaction commit from inside sysfs
1012 */
1013 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
1014 wake_up_process(fs_info->transaction_kthread);
1015
1016 return len;
1017 }
1018 BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
1019
1020 static ssize_t btrfs_nodesize_show(struct kobject *kobj,
1021 struct kobj_attribute *a, char *buf)
1022 {
1023 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1024
1025 return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize);
1026 }
1027
1028 BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
1029
1030 static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
1031 struct kobj_attribute *a, char *buf)
1032 {
1033 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1034
1035 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
1036 }
1037
1038 BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
1039
1040 static ssize_t btrfs_commit_stats_show(struct kobject *kobj,
1041 struct kobj_attribute *a, char *buf)
1042 {
1043 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1044
1045 return sysfs_emit(buf,
1046 "commits %llu\n"
1047 "last_commit_ms %llu\n"
1048 "max_commit_ms %llu\n"
1049 "total_commit_ms %llu\n",
1050 fs_info->commit_stats.commit_count,
1051 div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC),
1052 div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC),
1053 div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC));
1054 }
1055
1056 static ssize_t btrfs_commit_stats_store(struct kobject *kobj,
1057 struct kobj_attribute *a,
1058 const char *buf, size_t len)
1059 {
1060 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1061 unsigned long val;
1062 int ret;
1063
1064 if (!fs_info)
1065 return -EPERM;
1066
1067 if (!capable(CAP_SYS_RESOURCE))
1068 return -EPERM;
1069
1070 ret = kstrtoul(buf, 10, &val);
1071 if (ret)
1072 return ret;
1073 if (val)
1074 return -EINVAL;
1075
1076 WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0);
1077
1078 return len;
1079 }
1080 BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store);
1081
1082 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
1083 struct kobj_attribute *a, char *buf)
1084 {
1085 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1086
1087 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
1088 }
1089
1090 BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
1091
1092 static ssize_t quota_override_show(struct kobject *kobj,
1093 struct kobj_attribute *a, char *buf)
1094 {
1095 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1096 int quota_override;
1097
1098 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1099 return sysfs_emit(buf, "%d\n", quota_override);
1100 }
1101
1102 static ssize_t quota_override_store(struct kobject *kobj,
1103 struct kobj_attribute *a,
1104 const char *buf, size_t len)
1105 {
1106 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1107 unsigned long knob;
1108 int err;
1109
1110 if (!fs_info)
1111 return -EPERM;
1112
1113 if (!capable(CAP_SYS_RESOURCE))
1114 return -EPERM;
1115
1116 err = kstrtoul(buf, 10, &knob);
1117 if (err)
1118 return err;
1119 if (knob > 1)
1120 return -EINVAL;
1121
1122 if (knob)
1123 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1124 else
1125 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1126
1127 return len;
1128 }
1129
1130 BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
1131
1132 static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
1133 struct kobj_attribute *a, char *buf)
1134 {
1135 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1136
1137 return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid);
1138 }
1139
1140 BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
1141
1142 static ssize_t btrfs_checksum_show(struct kobject *kobj,
1143 struct kobj_attribute *a, char *buf)
1144 {
1145 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1146 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
1147
1148 return sysfs_emit(buf, "%s (%s)\n",
1149 btrfs_super_csum_name(csum_type),
1150 crypto_shash_driver_name(fs_info->csum_shash));
1151 }
1152
1153 BTRFS_ATTR(, checksum, btrfs_checksum_show);
1154
1155 static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
1156 struct kobj_attribute *a, char *buf)
1157 {
1158 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1159 const char *str;
1160
1161 switch (READ_ONCE(fs_info->exclusive_operation)) {
1162 case BTRFS_EXCLOP_NONE:
1163 str = "none\n";
1164 break;
1165 case BTRFS_EXCLOP_BALANCE:
1166 str = "balance\n";
1167 break;
1168 case BTRFS_EXCLOP_BALANCE_PAUSED:
1169 str = "balance paused\n";
1170 break;
1171 case BTRFS_EXCLOP_DEV_ADD:
1172 str = "device add\n";
1173 break;
1174 case BTRFS_EXCLOP_DEV_REMOVE:
1175 str = "device remove\n";
1176 break;
1177 case BTRFS_EXCLOP_DEV_REPLACE:
1178 str = "device replace\n";
1179 break;
1180 case BTRFS_EXCLOP_RESIZE:
1181 str = "resize\n";
1182 break;
1183 case BTRFS_EXCLOP_SWAP_ACTIVATE:
1184 str = "swap activate\n";
1185 break;
1186 default:
1187 str = "UNKNOWN\n";
1188 break;
1189 }
1190 return sysfs_emit(buf, "%s", str);
1191 }
1192 BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
1193
1194 static ssize_t btrfs_generation_show(struct kobject *kobj,
1195 struct kobj_attribute *a, char *buf)
1196 {
1197 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1198
1199 return sysfs_emit(buf, "%llu\n", fs_info->generation);
1200 }
1201 BTRFS_ATTR(, generation, btrfs_generation_show);
1202
1203 static const char * const btrfs_read_policy_name[] = { "pid" };
1204
1205 static ssize_t btrfs_read_policy_show(struct kobject *kobj,
1206 struct kobj_attribute *a, char *buf)
1207 {
1208 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1209 ssize_t ret = 0;
1210 int i;
1211
1212 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1213 if (fs_devices->read_policy == i)
1214 ret += sysfs_emit_at(buf, ret, "%s[%s]",
1215 (ret == 0 ? "" : " "),
1216 btrfs_read_policy_name[i]);
1217 else
1218 ret += sysfs_emit_at(buf, ret, "%s%s",
1219 (ret == 0 ? "" : " "),
1220 btrfs_read_policy_name[i]);
1221 }
1222
1223 ret += sysfs_emit_at(buf, ret, "\n");
1224
1225 return ret;
1226 }
1227
1228 static ssize_t btrfs_read_policy_store(struct kobject *kobj,
1229 struct kobj_attribute *a,
1230 const char *buf, size_t len)
1231 {
1232 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1233 int i;
1234
1235 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1236 if (sysfs_streq(buf, btrfs_read_policy_name[i])) {
1237 if (i != fs_devices->read_policy) {
1238 fs_devices->read_policy = i;
1239 btrfs_info(fs_devices->fs_info,
1240 "read policy set to '%s'",
1241 btrfs_read_policy_name[i]);
1242 }
1243 return len;
1244 }
1245 }
1246
1247 return -EINVAL;
1248 }
1249 BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
1250
1251 static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
1252 struct kobj_attribute *a,
1253 char *buf)
1254 {
1255 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1256
1257 return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
1258 }
1259
1260 static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
1261 struct kobj_attribute *a,
1262 const char *buf, size_t len)
1263 {
1264 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1265 int thresh;
1266 int ret;
1267
1268 ret = kstrtoint(buf, 10, &thresh);
1269 if (ret)
1270 return ret;
1271
1272 #ifdef CONFIG_BTRFS_DEBUG
1273 if (thresh != 0 && (thresh > 100))
1274 return -EINVAL;
1275 #else
1276 if (thresh != 0 && (thresh <= 50 || thresh > 100))
1277 return -EINVAL;
1278 #endif
1279
1280 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
1281
1282 return len;
1283 }
1284 BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
1285 btrfs_bg_reclaim_threshold_store);
1286
1287 /*
1288 * Per-filesystem information and stats.
1289 *
1290 * Path: /sys/fs/btrfs/<uuid>/
1291 */
1292 static const struct attribute *btrfs_attrs[] = {
1293 BTRFS_ATTR_PTR(, label),
1294 BTRFS_ATTR_PTR(, nodesize),
1295 BTRFS_ATTR_PTR(, sectorsize),
1296 BTRFS_ATTR_PTR(, clone_alignment),
1297 BTRFS_ATTR_PTR(, quota_override),
1298 BTRFS_ATTR_PTR(, metadata_uuid),
1299 BTRFS_ATTR_PTR(, checksum),
1300 BTRFS_ATTR_PTR(, exclusive_operation),
1301 BTRFS_ATTR_PTR(, generation),
1302 BTRFS_ATTR_PTR(, read_policy),
1303 BTRFS_ATTR_PTR(, bg_reclaim_threshold),
1304 BTRFS_ATTR_PTR(, commit_stats),
1305 NULL,
1306 };
1307
1308 static void btrfs_release_fsid_kobj(struct kobject *kobj)
1309 {
1310 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
1311
1312 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
1313 complete(&fs_devs->kobj_unregister);
1314 }
1315
1316 static const struct kobj_type btrfs_ktype = {
1317 .sysfs_ops = &kobj_sysfs_ops,
1318 .release = btrfs_release_fsid_kobj,
1319 };
1320
1321 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
1322 {
1323 if (kobj->ktype != &btrfs_ktype)
1324 return NULL;
1325 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
1326 }
1327
1328 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1329 {
1330 if (kobj->ktype != &btrfs_ktype)
1331 return NULL;
1332 return to_fs_devs(kobj)->fs_info;
1333 }
1334
1335 static struct kobject *get_btrfs_kobj(struct kobject *kobj)
1336 {
1337 while (kobj) {
1338 if (kobj->ktype == &btrfs_ktype)
1339 return kobj;
1340 kobj = kobj->parent;
1341 }
1342 return NULL;
1343 }
1344
1345 #define NUM_FEATURE_BITS 64
1346 #define BTRFS_FEATURE_NAME_MAX 13
1347 static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1348 static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1349
1350 static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) ==
1351 ARRAY_SIZE(btrfs_feature_attrs));
1352 static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) ==
1353 ARRAY_SIZE(btrfs_feature_attrs[0]));
1354
1355 static const u64 supported_feature_masks[FEAT_MAX] = {
1356 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1357 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1358 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1359 };
1360
1361 static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1362 {
1363 int set;
1364
1365 for (set = 0; set < FEAT_MAX; set++) {
1366 int i;
1367 struct attribute *attrs[2];
1368 struct attribute_group agroup = {
1369 .name = "features",
1370 .attrs = attrs,
1371 };
1372 u64 features = get_features(fs_info, set);
1373 features &= ~supported_feature_masks[set];
1374
1375 if (!features)
1376 continue;
1377
1378 attrs[1] = NULL;
1379 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1380 struct btrfs_feature_attr *fa;
1381
1382 if (!(features & (1ULL << i)))
1383 continue;
1384
1385 fa = &btrfs_feature_attrs[set][i];
1386 attrs[0] = &fa->kobj_attr.attr;
1387 if (add) {
1388 int ret;
1389 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1390 &agroup);
1391 if (ret)
1392 return ret;
1393 } else
1394 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1395 &agroup);
1396 }
1397
1398 }
1399 return 0;
1400 }
1401
1402 static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1403 {
1404 if (fs_devs->devinfo_kobj) {
1405 kobject_del(fs_devs->devinfo_kobj);
1406 kobject_put(fs_devs->devinfo_kobj);
1407 fs_devs->devinfo_kobj = NULL;
1408 }
1409
1410 if (fs_devs->devices_kobj) {
1411 kobject_del(fs_devs->devices_kobj);
1412 kobject_put(fs_devs->devices_kobj);
1413 fs_devs->devices_kobj = NULL;
1414 }
1415
1416 if (fs_devs->fsid_kobj.state_initialized) {
1417 kobject_del(&fs_devs->fsid_kobj);
1418 kobject_put(&fs_devs->fsid_kobj);
1419 wait_for_completion(&fs_devs->kobj_unregister);
1420 }
1421 }
1422
1423 /* when fs_devs is NULL it will remove all fsid kobject */
1424 void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1425 {
1426 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1427
1428 if (fs_devs) {
1429 __btrfs_sysfs_remove_fsid(fs_devs);
1430 return;
1431 }
1432
1433 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1434 __btrfs_sysfs_remove_fsid(fs_devs);
1435 }
1436 }
1437
1438 static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1439 {
1440 struct btrfs_device *device;
1441 struct btrfs_fs_devices *seed;
1442
1443 list_for_each_entry(device, &fs_devices->devices, dev_list)
1444 btrfs_sysfs_remove_device(device);
1445
1446 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1447 list_for_each_entry(device, &seed->devices, dev_list)
1448 btrfs_sysfs_remove_device(device);
1449 }
1450 }
1451
1452 void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1453 {
1454 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1455
1456 sysfs_remove_link(fsid_kobj, "bdi");
1457
1458 if (fs_info->space_info_kobj) {
1459 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1460 kobject_del(fs_info->space_info_kobj);
1461 kobject_put(fs_info->space_info_kobj);
1462 }
1463 if (fs_info->discard_kobj) {
1464 sysfs_remove_files(fs_info->discard_kobj, discard_attrs);
1465 kobject_del(fs_info->discard_kobj);
1466 kobject_put(fs_info->discard_kobj);
1467 }
1468 #ifdef CONFIG_BTRFS_DEBUG
1469 if (fs_info->debug_kobj) {
1470 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1471 kobject_del(fs_info->debug_kobj);
1472 kobject_put(fs_info->debug_kobj);
1473 }
1474 #endif
1475 addrm_unknown_feature_attrs(fs_info, false);
1476 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1477 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1478 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1479 }
1480
1481 static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1482 [FEAT_COMPAT] = "compat",
1483 [FEAT_COMPAT_RO] = "compat_ro",
1484 [FEAT_INCOMPAT] = "incompat",
1485 };
1486
1487 const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1488 {
1489 return btrfs_feature_set_names[set];
1490 }
1491
1492 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1493 {
1494 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1495 int len = 0;
1496 int i;
1497 char *str;
1498
1499 str = kmalloc(bufsize, GFP_KERNEL);
1500 if (!str)
1501 return str;
1502
1503 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1504 const char *name;
1505
1506 if (!(flags & (1ULL << i)))
1507 continue;
1508
1509 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1510 len += scnprintf(str + len, bufsize - len, "%s%s",
1511 len ? "," : "", name);
1512 }
1513
1514 return str;
1515 }
1516
1517 static void init_feature_attrs(void)
1518 {
1519 struct btrfs_feature_attr *fa;
1520 int set, i;
1521
1522 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1523 memset(btrfs_unknown_feature_names, 0,
1524 sizeof(btrfs_unknown_feature_names));
1525
1526 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1527 struct btrfs_feature_attr *sfa;
1528 struct attribute *a = btrfs_supported_feature_attrs[i];
1529 int bit;
1530 sfa = attr_to_btrfs_feature_attr(a);
1531 bit = ilog2(sfa->feature_bit);
1532 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1533
1534 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1535 }
1536
1537 for (set = 0; set < FEAT_MAX; set++) {
1538 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1539 char *name = btrfs_unknown_feature_names[set][i];
1540 fa = &btrfs_feature_attrs[set][i];
1541
1542 if (fa->kobj_attr.attr.name)
1543 continue;
1544
1545 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1546 btrfs_feature_set_names[set], i);
1547
1548 fa->kobj_attr.attr.name = name;
1549 fa->kobj_attr.attr.mode = S_IRUGO;
1550 fa->feature_set = set;
1551 fa->feature_bit = 1ULL << i;
1552 }
1553 }
1554 }
1555
1556 /*
1557 * Create a sysfs entry for a given block group type at path
1558 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1559 */
1560 void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1561 {
1562 struct btrfs_fs_info *fs_info = cache->fs_info;
1563 struct btrfs_space_info *space_info = cache->space_info;
1564 struct raid_kobject *rkobj;
1565 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1566 unsigned int nofs_flag;
1567 int ret;
1568
1569 /*
1570 * Setup a NOFS context because kobject_add(), deep in its call chain,
1571 * does GFP_KERNEL allocations, and we are often called in a context
1572 * where if reclaim is triggered we can deadlock (we are either holding
1573 * a transaction handle or some lock required for a transaction
1574 * commit).
1575 */
1576 nofs_flag = memalloc_nofs_save();
1577
1578 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1579 if (!rkobj) {
1580 memalloc_nofs_restore(nofs_flag);
1581 btrfs_warn(cache->fs_info,
1582 "couldn't alloc memory for raid level kobject");
1583 return;
1584 }
1585
1586 rkobj->flags = cache->flags;
1587 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1588
1589 /*
1590 * We call this either on mount, or if we've created a block group for a
1591 * new index type while running (i.e. when restriping). The running
1592 * case is tricky because we could race with other threads, so we need
1593 * to have this check to make sure we didn't already init the kobject.
1594 *
1595 * We don't have to protect on the free side because it only happens on
1596 * unmount.
1597 */
1598 spin_lock(&space_info->lock);
1599 if (space_info->block_group_kobjs[index]) {
1600 spin_unlock(&space_info->lock);
1601 kobject_put(&rkobj->kobj);
1602 return;
1603 } else {
1604 space_info->block_group_kobjs[index] = &rkobj->kobj;
1605 }
1606 spin_unlock(&space_info->lock);
1607
1608 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1609 btrfs_bg_type_to_raid_name(rkobj->flags));
1610 memalloc_nofs_restore(nofs_flag);
1611 if (ret) {
1612 spin_lock(&space_info->lock);
1613 space_info->block_group_kobjs[index] = NULL;
1614 spin_unlock(&space_info->lock);
1615 kobject_put(&rkobj->kobj);
1616 btrfs_warn(fs_info,
1617 "failed to add kobject for block cache, ignoring");
1618 return;
1619 }
1620 }
1621
1622 /*
1623 * Remove sysfs directories for all block group types of a given space info and
1624 * the space info as well
1625 */
1626 void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1627 {
1628 int i;
1629
1630 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1631 struct kobject *kobj;
1632
1633 kobj = space_info->block_group_kobjs[i];
1634 space_info->block_group_kobjs[i] = NULL;
1635 if (kobj) {
1636 kobject_del(kobj);
1637 kobject_put(kobj);
1638 }
1639 }
1640 kobject_del(&space_info->kobj);
1641 kobject_put(&space_info->kobj);
1642 }
1643
1644 static const char *alloc_name(u64 flags)
1645 {
1646 switch (flags) {
1647 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1648 return "mixed";
1649 case BTRFS_BLOCK_GROUP_METADATA:
1650 return "metadata";
1651 case BTRFS_BLOCK_GROUP_DATA:
1652 return "data";
1653 case BTRFS_BLOCK_GROUP_SYSTEM:
1654 return "system";
1655 default:
1656 WARN_ON(1);
1657 return "invalid-combination";
1658 }
1659 }
1660
1661 /*
1662 * Create a sysfs entry for a space info type at path
1663 * /sys/fs/btrfs/UUID/allocation/TYPE
1664 */
1665 int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1666 struct btrfs_space_info *space_info)
1667 {
1668 int ret;
1669
1670 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1671 fs_info->space_info_kobj, "%s",
1672 alloc_name(space_info->flags));
1673 if (ret) {
1674 kobject_put(&space_info->kobj);
1675 return ret;
1676 }
1677
1678 return 0;
1679 }
1680
1681 void btrfs_sysfs_remove_device(struct btrfs_device *device)
1682 {
1683 struct kobject *devices_kobj;
1684
1685 /*
1686 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1687 * fs_info::fs_devices.
1688 */
1689 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1690 ASSERT(devices_kobj);
1691
1692 if (device->bdev)
1693 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1694
1695 if (device->devid_kobj.state_initialized) {
1696 kobject_del(&device->devid_kobj);
1697 kobject_put(&device->devid_kobj);
1698 wait_for_completion(&device->kobj_unregister);
1699 }
1700 }
1701
1702 static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1703 struct kobj_attribute *a,
1704 char *buf)
1705 {
1706 int val;
1707 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1708 devid_kobj);
1709
1710 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1711
1712 return sysfs_emit(buf, "%d\n", val);
1713 }
1714 BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1715
1716 static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1717 struct kobj_attribute *a, char *buf)
1718 {
1719 int val;
1720 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1721 devid_kobj);
1722
1723 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1724
1725 return sysfs_emit(buf, "%d\n", val);
1726 }
1727 BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1728
1729 static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1730 struct kobj_attribute *a,
1731 char *buf)
1732 {
1733 int val;
1734 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1735 devid_kobj);
1736
1737 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1738
1739 return sysfs_emit(buf, "%d\n", val);
1740 }
1741 BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1742
1743 static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
1744 struct kobj_attribute *a,
1745 char *buf)
1746 {
1747 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1748 devid_kobj);
1749
1750 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max));
1751 }
1752
1753 static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
1754 struct kobj_attribute *a,
1755 const char *buf, size_t len)
1756 {
1757 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1758 devid_kobj);
1759 char *endptr;
1760 unsigned long long limit;
1761
1762 limit = memparse(buf, &endptr);
1763 WRITE_ONCE(device->scrub_speed_max, limit);
1764 return len;
1765 }
1766 BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show,
1767 btrfs_devinfo_scrub_speed_max_store);
1768
1769 static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1770 struct kobj_attribute *a, char *buf)
1771 {
1772 int val;
1773 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1774 devid_kobj);
1775
1776 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1777
1778 return sysfs_emit(buf, "%d\n", val);
1779 }
1780 BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1781
1782 static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj,
1783 struct kobj_attribute *a, char *buf)
1784 {
1785 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1786 devid_kobj);
1787
1788 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid);
1789 }
1790 BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show);
1791
1792 static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
1793 struct kobj_attribute *a, char *buf)
1794 {
1795 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1796 devid_kobj);
1797
1798 if (!device->dev_stats_valid)
1799 return sysfs_emit(buf, "invalid\n");
1800
1801 /*
1802 * Print all at once so we get a snapshot of all values from the same
1803 * time. Keep them in sync and in order of definition of
1804 * btrfs_dev_stat_values.
1805 */
1806 return sysfs_emit(buf,
1807 "write_errs %d\n"
1808 "read_errs %d\n"
1809 "flush_errs %d\n"
1810 "corruption_errs %d\n"
1811 "generation_errs %d\n",
1812 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS),
1813 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS),
1814 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS),
1815 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS),
1816 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS));
1817 }
1818 BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show);
1819
1820 /*
1821 * Information about one device.
1822 *
1823 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/
1824 */
1825 static struct attribute *devid_attrs[] = {
1826 BTRFS_ATTR_PTR(devid, error_stats),
1827 BTRFS_ATTR_PTR(devid, fsid),
1828 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1829 BTRFS_ATTR_PTR(devid, missing),
1830 BTRFS_ATTR_PTR(devid, replace_target),
1831 BTRFS_ATTR_PTR(devid, scrub_speed_max),
1832 BTRFS_ATTR_PTR(devid, writeable),
1833 NULL
1834 };
1835 ATTRIBUTE_GROUPS(devid);
1836
1837 static void btrfs_release_devid_kobj(struct kobject *kobj)
1838 {
1839 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1840 devid_kobj);
1841
1842 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1843 complete(&device->kobj_unregister);
1844 }
1845
1846 static const struct kobj_type devid_ktype = {
1847 .sysfs_ops = &kobj_sysfs_ops,
1848 .default_groups = devid_groups,
1849 .release = btrfs_release_devid_kobj,
1850 };
1851
1852 int btrfs_sysfs_add_device(struct btrfs_device *device)
1853 {
1854 int ret;
1855 unsigned int nofs_flag;
1856 struct kobject *devices_kobj;
1857 struct kobject *devinfo_kobj;
1858
1859 /*
1860 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
1861 * for the seed fs_devices
1862 */
1863 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1864 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
1865 ASSERT(devices_kobj);
1866 ASSERT(devinfo_kobj);
1867
1868 nofs_flag = memalloc_nofs_save();
1869
1870 if (device->bdev) {
1871 struct kobject *disk_kobj = bdev_kobj(device->bdev);
1872
1873 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
1874 if (ret) {
1875 btrfs_warn(device->fs_info,
1876 "creating sysfs device link for devid %llu failed: %d",
1877 device->devid, ret);
1878 goto out;
1879 }
1880 }
1881
1882 init_completion(&device->kobj_unregister);
1883 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
1884 devinfo_kobj, "%llu", device->devid);
1885 if (ret) {
1886 kobject_put(&device->devid_kobj);
1887 btrfs_warn(device->fs_info,
1888 "devinfo init for devid %llu failed: %d",
1889 device->devid, ret);
1890 }
1891
1892 out:
1893 memalloc_nofs_restore(nofs_flag);
1894 return ret;
1895 }
1896
1897 static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
1898 {
1899 int ret;
1900 struct btrfs_device *device;
1901 struct btrfs_fs_devices *seed;
1902
1903 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1904 ret = btrfs_sysfs_add_device(device);
1905 if (ret)
1906 goto fail;
1907 }
1908
1909 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1910 list_for_each_entry(device, &seed->devices, dev_list) {
1911 ret = btrfs_sysfs_add_device(device);
1912 if (ret)
1913 goto fail;
1914 }
1915 }
1916
1917 return 0;
1918
1919 fail:
1920 btrfs_sysfs_remove_fs_devices(fs_devices);
1921 return ret;
1922 }
1923
1924 void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1925 {
1926 int ret;
1927
1928 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1929 if (ret)
1930 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1931 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1932 &disk_to_dev(bdev->bd_disk)->kobj);
1933 }
1934
1935 void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
1936
1937 {
1938 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1939
1940 /*
1941 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1942 * directory
1943 */
1944 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
1945 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1946 btrfs_warn(fs_devices->fs_info,
1947 "sysfs: failed to create fsid for sprout");
1948 }
1949
1950 void btrfs_sysfs_update_devid(struct btrfs_device *device)
1951 {
1952 char tmp[24];
1953
1954 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
1955
1956 if (kobject_rename(&device->devid_kobj, tmp))
1957 btrfs_warn(device->fs_devices->fs_info,
1958 "sysfs: failed to update devid for %llu",
1959 device->devid);
1960 }
1961
1962 /* /sys/fs/btrfs/ entry */
1963 static struct kset *btrfs_kset;
1964
1965 /*
1966 * Creates:
1967 * /sys/fs/btrfs/UUID
1968 *
1969 * Can be called by the device discovery thread.
1970 */
1971 int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
1972 {
1973 int error;
1974
1975 init_completion(&fs_devs->kobj_unregister);
1976 fs_devs->fsid_kobj.kset = btrfs_kset;
1977 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
1978 "%pU", fs_devs->fsid);
1979 if (error) {
1980 kobject_put(&fs_devs->fsid_kobj);
1981 return error;
1982 }
1983
1984 fs_devs->devices_kobj = kobject_create_and_add("devices",
1985 &fs_devs->fsid_kobj);
1986 if (!fs_devs->devices_kobj) {
1987 btrfs_err(fs_devs->fs_info,
1988 "failed to init sysfs device interface");
1989 btrfs_sysfs_remove_fsid(fs_devs);
1990 return -ENOMEM;
1991 }
1992
1993 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
1994 &fs_devs->fsid_kobj);
1995 if (!fs_devs->devinfo_kobj) {
1996 btrfs_err(fs_devs->fs_info,
1997 "failed to init sysfs devinfo kobject");
1998 btrfs_sysfs_remove_fsid(fs_devs);
1999 return -ENOMEM;
2000 }
2001
2002 return 0;
2003 }
2004
2005 int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
2006 {
2007 int error;
2008 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
2009 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
2010
2011 error = btrfs_sysfs_add_fs_devices(fs_devs);
2012 if (error)
2013 return error;
2014
2015 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
2016 if (error) {
2017 btrfs_sysfs_remove_fs_devices(fs_devs);
2018 return error;
2019 }
2020
2021 error = sysfs_create_group(fsid_kobj,
2022 &btrfs_feature_attr_group);
2023 if (error)
2024 goto failure;
2025
2026 #ifdef CONFIG_BTRFS_DEBUG
2027 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
2028 if (!fs_info->debug_kobj) {
2029 error = -ENOMEM;
2030 goto failure;
2031 }
2032
2033 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
2034 if (error)
2035 goto failure;
2036 #endif
2037
2038 /* Discard directory */
2039 fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj);
2040 if (!fs_info->discard_kobj) {
2041 error = -ENOMEM;
2042 goto failure;
2043 }
2044
2045 error = sysfs_create_files(fs_info->discard_kobj, discard_attrs);
2046 if (error)
2047 goto failure;
2048
2049 error = addrm_unknown_feature_attrs(fs_info, true);
2050 if (error)
2051 goto failure;
2052
2053 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
2054 if (error)
2055 goto failure;
2056
2057 fs_info->space_info_kobj = kobject_create_and_add("allocation",
2058 fsid_kobj);
2059 if (!fs_info->space_info_kobj) {
2060 error = -ENOMEM;
2061 goto failure;
2062 }
2063
2064 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
2065 if (error)
2066 goto failure;
2067
2068 return 0;
2069 failure:
2070 btrfs_sysfs_remove_mounted(fs_info);
2071 return error;
2072 }
2073
2074 static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj,
2075 struct kobj_attribute *a,
2076 char *buf)
2077 {
2078 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2079 bool enabled;
2080
2081 spin_lock(&fs_info->qgroup_lock);
2082 enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON;
2083 spin_unlock(&fs_info->qgroup_lock);
2084
2085 return sysfs_emit(buf, "%d\n", enabled);
2086 }
2087 BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show);
2088
2089 static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj,
2090 struct kobj_attribute *a,
2091 char *buf)
2092 {
2093 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2094 bool inconsistent;
2095
2096 spin_lock(&fs_info->qgroup_lock);
2097 inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT);
2098 spin_unlock(&fs_info->qgroup_lock);
2099
2100 return sysfs_emit(buf, "%d\n", inconsistent);
2101 }
2102 BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show);
2103
2104 static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj,
2105 struct kobj_attribute *a,
2106 char *buf)
2107 {
2108 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2109 u8 result;
2110
2111 spin_lock(&fs_info->qgroup_lock);
2112 result = fs_info->qgroup_drop_subtree_thres;
2113 spin_unlock(&fs_info->qgroup_lock);
2114
2115 return sysfs_emit(buf, "%d\n", result);
2116 }
2117
2118 static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj,
2119 struct kobj_attribute *a,
2120 const char *buf, size_t len)
2121 {
2122 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2123 u8 new_thres;
2124 int ret;
2125
2126 ret = kstrtou8(buf, 10, &new_thres);
2127 if (ret)
2128 return -EINVAL;
2129
2130 if (new_thres > BTRFS_MAX_LEVEL)
2131 return -EINVAL;
2132
2133 spin_lock(&fs_info->qgroup_lock);
2134 fs_info->qgroup_drop_subtree_thres = new_thres;
2135 spin_unlock(&fs_info->qgroup_lock);
2136
2137 return len;
2138 }
2139 BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show,
2140 qgroup_drop_subtree_thres_store);
2141
2142 /*
2143 * Qgroups global info
2144 *
2145 * Path: /sys/fs/btrfs/<uuid>/qgroups/
2146 */
2147 static struct attribute *qgroups_attrs[] = {
2148 BTRFS_ATTR_PTR(qgroups, enabled),
2149 BTRFS_ATTR_PTR(qgroups, inconsistent),
2150 BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold),
2151 NULL
2152 };
2153 ATTRIBUTE_GROUPS(qgroups);
2154
2155 static void qgroups_release(struct kobject *kobj)
2156 {
2157 kfree(kobj);
2158 }
2159
2160 static const struct kobj_type qgroups_ktype = {
2161 .sysfs_ops = &kobj_sysfs_ops,
2162 .default_groups = qgroups_groups,
2163 .release = qgroups_release,
2164 };
2165
2166 static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
2167 {
2168 return to_fs_info(kobj->parent->parent);
2169 }
2170
2171 #define QGROUP_ATTR(_member, _show_name) \
2172 static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
2173 struct kobj_attribute *a, \
2174 char *buf) \
2175 { \
2176 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2177 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2178 struct btrfs_qgroup, kobj); \
2179 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
2180 } \
2181 BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
2182
2183 #define QGROUP_RSV_ATTR(_name, _type) \
2184 static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
2185 struct kobj_attribute *a, \
2186 char *buf) \
2187 { \
2188 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2189 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2190 struct btrfs_qgroup, kobj); \
2191 return btrfs_show_u64(&qgroup->rsv.values[_type], \
2192 &fs_info->qgroup_lock, buf); \
2193 } \
2194 BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
2195
2196 QGROUP_ATTR(rfer, referenced);
2197 QGROUP_ATTR(excl, exclusive);
2198 QGROUP_ATTR(max_rfer, max_referenced);
2199 QGROUP_ATTR(max_excl, max_exclusive);
2200 QGROUP_ATTR(lim_flags, limit_flags);
2201 QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
2202 QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
2203 QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
2204
2205 /*
2206 * Qgroup information.
2207 *
2208 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/
2209 */
2210 static struct attribute *qgroup_attrs[] = {
2211 BTRFS_ATTR_PTR(qgroup, referenced),
2212 BTRFS_ATTR_PTR(qgroup, exclusive),
2213 BTRFS_ATTR_PTR(qgroup, max_referenced),
2214 BTRFS_ATTR_PTR(qgroup, max_exclusive),
2215 BTRFS_ATTR_PTR(qgroup, limit_flags),
2216 BTRFS_ATTR_PTR(qgroup, rsv_data),
2217 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
2218 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
2219 NULL
2220 };
2221 ATTRIBUTE_GROUPS(qgroup);
2222
2223 static void qgroup_release(struct kobject *kobj)
2224 {
2225 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
2226
2227 memset(&qgroup->kobj, 0, sizeof(*kobj));
2228 }
2229
2230 static const struct kobj_type qgroup_ktype = {
2231 .sysfs_ops = &kobj_sysfs_ops,
2232 .release = qgroup_release,
2233 .default_groups = qgroup_groups,
2234 };
2235
2236 int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
2237 struct btrfs_qgroup *qgroup)
2238 {
2239 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
2240 int ret;
2241
2242 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2243 return 0;
2244 if (qgroup->kobj.state_initialized)
2245 return 0;
2246 if (!qgroups_kobj)
2247 return -EINVAL;
2248
2249 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
2250 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
2251 btrfs_qgroup_subvolid(qgroup->qgroupid));
2252 if (ret < 0)
2253 kobject_put(&qgroup->kobj);
2254
2255 return ret;
2256 }
2257
2258 void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
2259 {
2260 struct btrfs_qgroup *qgroup;
2261 struct btrfs_qgroup *next;
2262
2263 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2264 return;
2265
2266 rbtree_postorder_for_each_entry_safe(qgroup, next,
2267 &fs_info->qgroup_tree, node)
2268 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
2269 if (fs_info->qgroups_kobj) {
2270 kobject_del(fs_info->qgroups_kobj);
2271 kobject_put(fs_info->qgroups_kobj);
2272 fs_info->qgroups_kobj = NULL;
2273 }
2274 }
2275
2276 /* Called when qgroups get initialized, thus there is no need for locking */
2277 int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
2278 {
2279 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2280 struct btrfs_qgroup *qgroup;
2281 struct btrfs_qgroup *next;
2282 int ret = 0;
2283
2284 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2285 return 0;
2286
2287 ASSERT(fsid_kobj);
2288 if (fs_info->qgroups_kobj)
2289 return 0;
2290
2291 fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
2292 if (!fs_info->qgroups_kobj)
2293 return -ENOMEM;
2294
2295 ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype,
2296 fsid_kobj, "qgroups");
2297 if (ret < 0)
2298 goto out;
2299
2300 rbtree_postorder_for_each_entry_safe(qgroup, next,
2301 &fs_info->qgroup_tree, node) {
2302 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
2303 if (ret < 0)
2304 goto out;
2305 }
2306
2307 out:
2308 if (ret < 0)
2309 btrfs_sysfs_del_qgroups(fs_info);
2310 return ret;
2311 }
2312
2313 void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
2314 struct btrfs_qgroup *qgroup)
2315 {
2316 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2317 return;
2318
2319 if (qgroup->kobj.state_initialized) {
2320 kobject_del(&qgroup->kobj);
2321 kobject_put(&qgroup->kobj);
2322 }
2323 }
2324
2325 /*
2326 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
2327 * values in superblock. Call after any changes to incompat/compat_ro flags
2328 */
2329 void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info)
2330 {
2331 struct kobject *fsid_kobj;
2332 int ret;
2333
2334 if (!fs_info)
2335 return;
2336
2337 fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2338 if (!fsid_kobj->state_initialized)
2339 return;
2340
2341 ret = sysfs_update_group(fsid_kobj, &btrfs_feature_attr_group);
2342 if (ret < 0)
2343 btrfs_warn(fs_info,
2344 "failed to update /sys/fs/btrfs/%pU/features: %d",
2345 fs_info->fs_devices->fsid, ret);
2346 }
2347
2348 int __init btrfs_init_sysfs(void)
2349 {
2350 int ret;
2351
2352 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
2353 if (!btrfs_kset)
2354 return -ENOMEM;
2355
2356 init_feature_attrs();
2357 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2358 if (ret)
2359 goto out2;
2360 ret = sysfs_merge_group(&btrfs_kset->kobj,
2361 &btrfs_static_feature_attr_group);
2362 if (ret)
2363 goto out_remove_group;
2364
2365 #ifdef CONFIG_BTRFS_DEBUG
2366 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2367 if (ret) {
2368 sysfs_unmerge_group(&btrfs_kset->kobj,
2369 &btrfs_static_feature_attr_group);
2370 goto out_remove_group;
2371 }
2372 #endif
2373
2374 return 0;
2375
2376 out_remove_group:
2377 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2378 out2:
2379 kset_unregister(btrfs_kset);
2380
2381 return ret;
2382 }
2383
2384 void __cold btrfs_exit_sysfs(void)
2385 {
2386 sysfs_unmerge_group(&btrfs_kset->kobj,
2387 &btrfs_static_feature_attr_group);
2388 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2389 #ifdef CONFIG_BTRFS_DEBUG
2390 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2391 #endif
2392 kset_unregister(btrfs_kset);
2393 }
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