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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
13#include "ctree.h"
14#include "disk-io.h"
15#include "transaction.h"
16#include "sysfs.h"
17#include "volumes.h"
18#include "space-info.h"
19#include "block-group.h"
20
21struct btrfs_feature_attr {
22 struct kobj_attribute kobj_attr;
23 enum btrfs_feature_set feature_set;
24 u64 feature_bit;
25};
26
27/* For raid type sysfs entries */
28struct raid_kobject {
29 u64 flags;
30 struct kobject kobj;
31};
32
33#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
34{ \
35 .attr = { .name = __stringify(_name), .mode = _mode }, \
36 .show = _show, \
37 .store = _store, \
38}
39
40#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
41 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
42 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
43
44#define BTRFS_ATTR(_prefix, _name, _show) \
45 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
46 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
47
48#define BTRFS_ATTR_PTR(_prefix, _name) \
49 (&btrfs_attr_##_prefix##_##_name.attr)
50
51#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
52static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
53 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
54 btrfs_feature_attr_show, \
55 btrfs_feature_attr_store), \
56 .feature_set = _feature_set, \
57 .feature_bit = _feature_prefix ##_## _feature_bit, \
58}
59#define BTRFS_FEAT_ATTR_PTR(_name) \
60 (&btrfs_attr_features_##_name.kobj_attr.attr)
61
62#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
63 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
64#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
65 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
66#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
67 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
68
69static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
70static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
71
72static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
73{
74 return container_of(a, struct btrfs_feature_attr, kobj_attr);
75}
76
77static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
78{
79 return container_of(attr, struct kobj_attribute, attr);
80}
81
82static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
83 struct attribute *attr)
84{
85 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
86}
87
88static u64 get_features(struct btrfs_fs_info *fs_info,
89 enum btrfs_feature_set set)
90{
91 struct btrfs_super_block *disk_super = fs_info->super_copy;
92 if (set == FEAT_COMPAT)
93 return btrfs_super_compat_flags(disk_super);
94 else if (set == FEAT_COMPAT_RO)
95 return btrfs_super_compat_ro_flags(disk_super);
96 else
97 return btrfs_super_incompat_flags(disk_super);
98}
99
100static void set_features(struct btrfs_fs_info *fs_info,
101 enum btrfs_feature_set set, u64 features)
102{
103 struct btrfs_super_block *disk_super = fs_info->super_copy;
104 if (set == FEAT_COMPAT)
105 btrfs_set_super_compat_flags(disk_super, features);
106 else if (set == FEAT_COMPAT_RO)
107 btrfs_set_super_compat_ro_flags(disk_super, features);
108 else
109 btrfs_set_super_incompat_flags(disk_super, features);
110}
111
112static int can_modify_feature(struct btrfs_feature_attr *fa)
113{
114 int val = 0;
115 u64 set, clear;
116 switch (fa->feature_set) {
117 case FEAT_COMPAT:
118 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
119 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
120 break;
121 case FEAT_COMPAT_RO:
122 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
123 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
124 break;
125 case FEAT_INCOMPAT:
126 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
127 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
128 break;
129 default:
130 pr_warn("btrfs: sysfs: unknown feature set %d\n",
131 fa->feature_set);
132 return 0;
133 }
134
135 if (set & fa->feature_bit)
136 val |= 1;
137 if (clear & fa->feature_bit)
138 val |= 2;
139
140 return val;
141}
142
143static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
144 struct kobj_attribute *a, char *buf)
145{
146 int val = 0;
147 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
148 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
149 if (fs_info) {
150 u64 features = get_features(fs_info, fa->feature_set);
151 if (features & fa->feature_bit)
152 val = 1;
153 } else
154 val = can_modify_feature(fa);
155
156 return snprintf(buf, PAGE_SIZE, "%d\n", val);
157}
158
159static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
160 struct kobj_attribute *a,
161 const char *buf, size_t count)
162{
163 struct btrfs_fs_info *fs_info;
164 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
165 u64 features, set, clear;
166 unsigned long val;
167 int ret;
168
169 fs_info = to_fs_info(kobj);
170 if (!fs_info)
171 return -EPERM;
172
173 if (sb_rdonly(fs_info->sb))
174 return -EROFS;
175
176 ret = kstrtoul(skip_spaces(buf), 0, &val);
177 if (ret)
178 return ret;
179
180 if (fa->feature_set == FEAT_COMPAT) {
181 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
182 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
183 } else if (fa->feature_set == FEAT_COMPAT_RO) {
184 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
185 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
186 } else {
187 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
188 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
189 }
190
191 features = get_features(fs_info, fa->feature_set);
192
193 /* Nothing to do */
194 if ((val && (features & fa->feature_bit)) ||
195 (!val && !(features & fa->feature_bit)))
196 return count;
197
198 if ((val && !(set & fa->feature_bit)) ||
199 (!val && !(clear & fa->feature_bit))) {
200 btrfs_info(fs_info,
201 "%sabling feature %s on mounted fs is not supported.",
202 val ? "En" : "Dis", fa->kobj_attr.attr.name);
203 return -EPERM;
204 }
205
206 btrfs_info(fs_info, "%s %s feature flag",
207 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
208
209 spin_lock(&fs_info->super_lock);
210 features = get_features(fs_info, fa->feature_set);
211 if (val)
212 features |= fa->feature_bit;
213 else
214 features &= ~fa->feature_bit;
215 set_features(fs_info, fa->feature_set, features);
216 spin_unlock(&fs_info->super_lock);
217
218 /*
219 * We don't want to do full transaction commit from inside sysfs
220 */
221 btrfs_set_pending(fs_info, COMMIT);
222 wake_up_process(fs_info->transaction_kthread);
223
224 return count;
225}
226
227static umode_t btrfs_feature_visible(struct kobject *kobj,
228 struct attribute *attr, int unused)
229{
230 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
231 umode_t mode = attr->mode;
232
233 if (fs_info) {
234 struct btrfs_feature_attr *fa;
235 u64 features;
236
237 fa = attr_to_btrfs_feature_attr(attr);
238 features = get_features(fs_info, fa->feature_set);
239
240 if (can_modify_feature(fa))
241 mode |= S_IWUSR;
242 else if (!(features & fa->feature_bit))
243 mode = 0;
244 }
245
246 return mode;
247}
248
249BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
250BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
251BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
252BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
253BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
254BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
255BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
256BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
257BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
258BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
259BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
260BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
261
262static struct attribute *btrfs_supported_feature_attrs[] = {
263 BTRFS_FEAT_ATTR_PTR(mixed_backref),
264 BTRFS_FEAT_ATTR_PTR(default_subvol),
265 BTRFS_FEAT_ATTR_PTR(mixed_groups),
266 BTRFS_FEAT_ATTR_PTR(compress_lzo),
267 BTRFS_FEAT_ATTR_PTR(compress_zstd),
268 BTRFS_FEAT_ATTR_PTR(big_metadata),
269 BTRFS_FEAT_ATTR_PTR(extended_iref),
270 BTRFS_FEAT_ATTR_PTR(raid56),
271 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
272 BTRFS_FEAT_ATTR_PTR(no_holes),
273 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
274 BTRFS_FEAT_ATTR_PTR(free_space_tree),
275 NULL
276};
277
278/*
279 * Features which depend on feature bits and may differ between each fs.
280 *
281 * /sys/fs/btrfs/features lists all available features of this kernel while
282 * /sys/fs/btrfs/UUID/features shows features of the fs which are enabled or
283 * can be changed online.
284 */
285static const struct attribute_group btrfs_feature_attr_group = {
286 .name = "features",
287 .is_visible = btrfs_feature_visible,
288 .attrs = btrfs_supported_feature_attrs,
289};
290
291static ssize_t rmdir_subvol_show(struct kobject *kobj,
292 struct kobj_attribute *ka, char *buf)
293{
294 return snprintf(buf, PAGE_SIZE, "0\n");
295}
296BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
297
298static struct attribute *btrfs_supported_static_feature_attrs[] = {
299 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
300 NULL
301};
302
303/*
304 * Features which only depend on kernel version.
305 *
306 * These are listed in /sys/fs/btrfs/features along with
307 * btrfs_feature_attr_group
308 */
309static const struct attribute_group btrfs_static_feature_attr_group = {
310 .name = "features",
311 .attrs = btrfs_supported_static_feature_attrs,
312};
313
314#ifdef CONFIG_BTRFS_DEBUG
315
316/*
317 * Runtime debugging exported via sysfs
318 *
319 * /sys/fs/btrfs/debug - applies to module or all filesystems
320 * /sys/fs/btrfs/UUID - applies only to the given filesystem
321 */
322static struct attribute *btrfs_debug_feature_attrs[] = {
323 NULL
324};
325
326static const struct attribute_group btrfs_debug_feature_attr_group = {
327 .name = "debug",
328 .attrs = btrfs_debug_feature_attrs,
329};
330
331#endif
332
333static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
334{
335 u64 val;
336 if (lock)
337 spin_lock(lock);
338 val = *value_ptr;
339 if (lock)
340 spin_unlock(lock);
341 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
342}
343
344static ssize_t global_rsv_size_show(struct kobject *kobj,
345 struct kobj_attribute *ka, char *buf)
346{
347 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
348 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
349 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
350}
351BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
352
353static ssize_t global_rsv_reserved_show(struct kobject *kobj,
354 struct kobj_attribute *a, char *buf)
355{
356 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
357 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
358 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
359}
360BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
361
362#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
363#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
364
365static ssize_t raid_bytes_show(struct kobject *kobj,
366 struct kobj_attribute *attr, char *buf);
367BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
368BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
369
370static ssize_t raid_bytes_show(struct kobject *kobj,
371 struct kobj_attribute *attr, char *buf)
372
373{
374 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
375 struct btrfs_block_group_cache *block_group;
376 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
377 u64 val = 0;
378
379 down_read(&sinfo->groups_sem);
380 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
381 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
382 val += block_group->key.offset;
383 else
384 val += btrfs_block_group_used(&block_group->item);
385 }
386 up_read(&sinfo->groups_sem);
387 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
388}
389
390static struct attribute *raid_attrs[] = {
391 BTRFS_ATTR_PTR(raid, total_bytes),
392 BTRFS_ATTR_PTR(raid, used_bytes),
393 NULL
394};
395ATTRIBUTE_GROUPS(raid);
396
397static void release_raid_kobj(struct kobject *kobj)
398{
399 kfree(to_raid_kobj(kobj));
400}
401
402static struct kobj_type btrfs_raid_ktype = {
403 .sysfs_ops = &kobj_sysfs_ops,
404 .release = release_raid_kobj,
405 .default_groups = raid_groups,
406};
407
408#define SPACE_INFO_ATTR(field) \
409static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
410 struct kobj_attribute *a, \
411 char *buf) \
412{ \
413 struct btrfs_space_info *sinfo = to_space_info(kobj); \
414 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
415} \
416BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
417
418static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
419 struct kobj_attribute *a,
420 char *buf)
421{
422 struct btrfs_space_info *sinfo = to_space_info(kobj);
423 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
424 return snprintf(buf, PAGE_SIZE, "%lld\n", val);
425}
426
427SPACE_INFO_ATTR(flags);
428SPACE_INFO_ATTR(total_bytes);
429SPACE_INFO_ATTR(bytes_used);
430SPACE_INFO_ATTR(bytes_pinned);
431SPACE_INFO_ATTR(bytes_reserved);
432SPACE_INFO_ATTR(bytes_may_use);
433SPACE_INFO_ATTR(bytes_readonly);
434SPACE_INFO_ATTR(disk_used);
435SPACE_INFO_ATTR(disk_total);
436BTRFS_ATTR(space_info, total_bytes_pinned,
437 btrfs_space_info_show_total_bytes_pinned);
438
439static struct attribute *space_info_attrs[] = {
440 BTRFS_ATTR_PTR(space_info, flags),
441 BTRFS_ATTR_PTR(space_info, total_bytes),
442 BTRFS_ATTR_PTR(space_info, bytes_used),
443 BTRFS_ATTR_PTR(space_info, bytes_pinned),
444 BTRFS_ATTR_PTR(space_info, bytes_reserved),
445 BTRFS_ATTR_PTR(space_info, bytes_may_use),
446 BTRFS_ATTR_PTR(space_info, bytes_readonly),
447 BTRFS_ATTR_PTR(space_info, disk_used),
448 BTRFS_ATTR_PTR(space_info, disk_total),
449 BTRFS_ATTR_PTR(space_info, total_bytes_pinned),
450 NULL,
451};
452ATTRIBUTE_GROUPS(space_info);
453
454static void space_info_release(struct kobject *kobj)
455{
456 struct btrfs_space_info *sinfo = to_space_info(kobj);
457 percpu_counter_destroy(&sinfo->total_bytes_pinned);
458 kfree(sinfo);
459}
460
461static struct kobj_type space_info_ktype = {
462 .sysfs_ops = &kobj_sysfs_ops,
463 .release = space_info_release,
464 .default_groups = space_info_groups,
465};
466
467static const struct attribute *allocation_attrs[] = {
468 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
469 BTRFS_ATTR_PTR(allocation, global_rsv_size),
470 NULL,
471};
472
473static ssize_t btrfs_label_show(struct kobject *kobj,
474 struct kobj_attribute *a, char *buf)
475{
476 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
477 char *label = fs_info->super_copy->label;
478 ssize_t ret;
479
480 spin_lock(&fs_info->super_lock);
481 ret = snprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
482 spin_unlock(&fs_info->super_lock);
483
484 return ret;
485}
486
487static ssize_t btrfs_label_store(struct kobject *kobj,
488 struct kobj_attribute *a,
489 const char *buf, size_t len)
490{
491 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
492 size_t p_len;
493
494 if (!fs_info)
495 return -EPERM;
496
497 if (sb_rdonly(fs_info->sb))
498 return -EROFS;
499
500 /*
501 * p_len is the len until the first occurrence of either
502 * '\n' or '\0'
503 */
504 p_len = strcspn(buf, "\n");
505
506 if (p_len >= BTRFS_LABEL_SIZE)
507 return -EINVAL;
508
509 spin_lock(&fs_info->super_lock);
510 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
511 memcpy(fs_info->super_copy->label, buf, p_len);
512 spin_unlock(&fs_info->super_lock);
513
514 /*
515 * We don't want to do full transaction commit from inside sysfs
516 */
517 btrfs_set_pending(fs_info, COMMIT);
518 wake_up_process(fs_info->transaction_kthread);
519
520 return len;
521}
522BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
523
524static ssize_t btrfs_nodesize_show(struct kobject *kobj,
525 struct kobj_attribute *a, char *buf)
526{
527 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
528
529 return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
530}
531
532BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
533
534static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
535 struct kobj_attribute *a, char *buf)
536{
537 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
538
539 return snprintf(buf, PAGE_SIZE, "%u\n",
540 fs_info->super_copy->sectorsize);
541}
542
543BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
544
545static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
546 struct kobj_attribute *a, char *buf)
547{
548 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
549
550 return snprintf(buf, PAGE_SIZE, "%u\n",
551 fs_info->super_copy->sectorsize);
552}
553
554BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
555
556static ssize_t quota_override_show(struct kobject *kobj,
557 struct kobj_attribute *a, char *buf)
558{
559 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
560 int quota_override;
561
562 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
563 return snprintf(buf, PAGE_SIZE, "%d\n", quota_override);
564}
565
566static ssize_t quota_override_store(struct kobject *kobj,
567 struct kobj_attribute *a,
568 const char *buf, size_t len)
569{
570 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
571 unsigned long knob;
572 int err;
573
574 if (!fs_info)
575 return -EPERM;
576
577 if (!capable(CAP_SYS_RESOURCE))
578 return -EPERM;
579
580 err = kstrtoul(buf, 10, &knob);
581 if (err)
582 return err;
583 if (knob > 1)
584 return -EINVAL;
585
586 if (knob)
587 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
588 else
589 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
590
591 return len;
592}
593
594BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
595
596static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
597 struct kobj_attribute *a, char *buf)
598{
599 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
600
601 return snprintf(buf, PAGE_SIZE, "%pU\n",
602 fs_info->fs_devices->metadata_uuid);
603}
604
605BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
606
607static const struct attribute *btrfs_attrs[] = {
608 BTRFS_ATTR_PTR(, label),
609 BTRFS_ATTR_PTR(, nodesize),
610 BTRFS_ATTR_PTR(, sectorsize),
611 BTRFS_ATTR_PTR(, clone_alignment),
612 BTRFS_ATTR_PTR(, quota_override),
613 BTRFS_ATTR_PTR(, metadata_uuid),
614 NULL,
615};
616
617static void btrfs_release_fsid_kobj(struct kobject *kobj)
618{
619 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
620
621 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
622 complete(&fs_devs->kobj_unregister);
623}
624
625static struct kobj_type btrfs_ktype = {
626 .sysfs_ops = &kobj_sysfs_ops,
627 .release = btrfs_release_fsid_kobj,
628};
629
630static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
631{
632 if (kobj->ktype != &btrfs_ktype)
633 return NULL;
634 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
635}
636
637static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
638{
639 if (kobj->ktype != &btrfs_ktype)
640 return NULL;
641 return to_fs_devs(kobj)->fs_info;
642}
643
644#define NUM_FEATURE_BITS 64
645#define BTRFS_FEATURE_NAME_MAX 13
646static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
647static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
648
649static const u64 supported_feature_masks[FEAT_MAX] = {
650 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
651 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
652 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
653};
654
655static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
656{
657 int set;
658
659 for (set = 0; set < FEAT_MAX; set++) {
660 int i;
661 struct attribute *attrs[2];
662 struct attribute_group agroup = {
663 .name = "features",
664 .attrs = attrs,
665 };
666 u64 features = get_features(fs_info, set);
667 features &= ~supported_feature_masks[set];
668
669 if (!features)
670 continue;
671
672 attrs[1] = NULL;
673 for (i = 0; i < NUM_FEATURE_BITS; i++) {
674 struct btrfs_feature_attr *fa;
675
676 if (!(features & (1ULL << i)))
677 continue;
678
679 fa = &btrfs_feature_attrs[set][i];
680 attrs[0] = &fa->kobj_attr.attr;
681 if (add) {
682 int ret;
683 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
684 &agroup);
685 if (ret)
686 return ret;
687 } else
688 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
689 &agroup);
690 }
691
692 }
693 return 0;
694}
695
696static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
697{
698 if (fs_devs->device_dir_kobj) {
699 kobject_del(fs_devs->device_dir_kobj);
700 kobject_put(fs_devs->device_dir_kobj);
701 fs_devs->device_dir_kobj = NULL;
702 }
703
704 if (fs_devs->fsid_kobj.state_initialized) {
705 kobject_del(&fs_devs->fsid_kobj);
706 kobject_put(&fs_devs->fsid_kobj);
707 wait_for_completion(&fs_devs->kobj_unregister);
708 }
709}
710
711/* when fs_devs is NULL it will remove all fsid kobject */
712void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
713{
714 struct list_head *fs_uuids = btrfs_get_fs_uuids();
715
716 if (fs_devs) {
717 __btrfs_sysfs_remove_fsid(fs_devs);
718 return;
719 }
720
721 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
722 __btrfs_sysfs_remove_fsid(fs_devs);
723 }
724}
725
726void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
727{
728 btrfs_reset_fs_info_ptr(fs_info);
729
730 if (fs_info->space_info_kobj) {
731 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
732 kobject_del(fs_info->space_info_kobj);
733 kobject_put(fs_info->space_info_kobj);
734 }
735 addrm_unknown_feature_attrs(fs_info, false);
736 sysfs_remove_group(&fs_info->fs_devices->fsid_kobj, &btrfs_feature_attr_group);
737 sysfs_remove_files(&fs_info->fs_devices->fsid_kobj, btrfs_attrs);
738 btrfs_sysfs_rm_device_link(fs_info->fs_devices, NULL);
739}
740
741static const char * const btrfs_feature_set_names[FEAT_MAX] = {
742 [FEAT_COMPAT] = "compat",
743 [FEAT_COMPAT_RO] = "compat_ro",
744 [FEAT_INCOMPAT] = "incompat",
745};
746
747const char * const btrfs_feature_set_name(enum btrfs_feature_set set)
748{
749 return btrfs_feature_set_names[set];
750}
751
752char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
753{
754 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
755 int len = 0;
756 int i;
757 char *str;
758
759 str = kmalloc(bufsize, GFP_KERNEL);
760 if (!str)
761 return str;
762
763 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
764 const char *name;
765
766 if (!(flags & (1ULL << i)))
767 continue;
768
769 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
770 len += snprintf(str + len, bufsize - len, "%s%s",
771 len ? "," : "", name);
772 }
773
774 return str;
775}
776
777static void init_feature_attrs(void)
778{
779 struct btrfs_feature_attr *fa;
780 int set, i;
781
782 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
783 ARRAY_SIZE(btrfs_feature_attrs));
784 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
785 ARRAY_SIZE(btrfs_feature_attrs[0]));
786
787 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
788 memset(btrfs_unknown_feature_names, 0,
789 sizeof(btrfs_unknown_feature_names));
790
791 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
792 struct btrfs_feature_attr *sfa;
793 struct attribute *a = btrfs_supported_feature_attrs[i];
794 int bit;
795 sfa = attr_to_btrfs_feature_attr(a);
796 bit = ilog2(sfa->feature_bit);
797 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
798
799 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
800 }
801
802 for (set = 0; set < FEAT_MAX; set++) {
803 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
804 char *name = btrfs_unknown_feature_names[set][i];
805 fa = &btrfs_feature_attrs[set][i];
806
807 if (fa->kobj_attr.attr.name)
808 continue;
809
810 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
811 btrfs_feature_set_names[set], i);
812
813 fa->kobj_attr.attr.name = name;
814 fa->kobj_attr.attr.mode = S_IRUGO;
815 fa->feature_set = set;
816 fa->feature_bit = 1ULL << i;
817 }
818 }
819}
820
821/*
822 * Create a sysfs entry for a given block group type at path
823 * /sys/fs/btrfs/UUID/allocation/data/TYPE
824 */
825void btrfs_sysfs_add_block_group_type(struct btrfs_block_group_cache *cache)
826{
827 struct btrfs_fs_info *fs_info = cache->fs_info;
828 struct btrfs_space_info *space_info = cache->space_info;
829 struct raid_kobject *rkobj;
830 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
831 unsigned int nofs_flag;
832 int ret;
833
834 /*
835 * Setup a NOFS context because kobject_add(), deep in its call chain,
836 * does GFP_KERNEL allocations, and we are often called in a context
837 * where if reclaim is triggered we can deadlock (we are either holding
838 * a transaction handle or some lock required for a transaction
839 * commit).
840 */
841 nofs_flag = memalloc_nofs_save();
842
843 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
844 if (!rkobj) {
845 memalloc_nofs_restore(nofs_flag);
846 btrfs_warn(cache->fs_info,
847 "couldn't alloc memory for raid level kobject");
848 return;
849 }
850
851 rkobj->flags = cache->flags;
852 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
853 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
854 btrfs_bg_type_to_raid_name(rkobj->flags));
855 memalloc_nofs_restore(nofs_flag);
856 if (ret) {
857 kobject_put(&rkobj->kobj);
858 btrfs_warn(fs_info,
859 "failed to add kobject for block cache, ignoring");
860 return;
861 }
862
863 space_info->block_group_kobjs[index] = &rkobj->kobj;
864}
865
866/*
867 * Remove sysfs directories for all block group types of a given space info and
868 * the space info as well
869 */
870void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
871{
872 int i;
873
874 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
875 struct kobject *kobj;
876
877 kobj = space_info->block_group_kobjs[i];
878 space_info->block_group_kobjs[i] = NULL;
879 if (kobj) {
880 kobject_del(kobj);
881 kobject_put(kobj);
882 }
883 }
884 kobject_del(&space_info->kobj);
885 kobject_put(&space_info->kobj);
886}
887
888static const char *alloc_name(u64 flags)
889{
890 switch (flags) {
891 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
892 return "mixed";
893 case BTRFS_BLOCK_GROUP_METADATA:
894 return "metadata";
895 case BTRFS_BLOCK_GROUP_DATA:
896 return "data";
897 case BTRFS_BLOCK_GROUP_SYSTEM:
898 return "system";
899 default:
900 WARN_ON(1);
901 return "invalid-combination";
902 };
903}
904
905/*
906 * Create a sysfs entry for a space info type at path
907 * /sys/fs/btrfs/UUID/allocation/TYPE
908 */
909int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
910 struct btrfs_space_info *space_info)
911{
912 int ret;
913
914 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
915 fs_info->space_info_kobj, "%s",
916 alloc_name(space_info->flags));
917 if (ret) {
918 kobject_put(&space_info->kobj);
919 return ret;
920 }
921
922 return 0;
923}
924
925/* when one_device is NULL, it removes all device links */
926
927int btrfs_sysfs_rm_device_link(struct btrfs_fs_devices *fs_devices,
928 struct btrfs_device *one_device)
929{
930 struct hd_struct *disk;
931 struct kobject *disk_kobj;
932
933 if (!fs_devices->device_dir_kobj)
934 return -EINVAL;
935
936 if (one_device && one_device->bdev) {
937 disk = one_device->bdev->bd_part;
938 disk_kobj = &part_to_dev(disk)->kobj;
939
940 sysfs_remove_link(fs_devices->device_dir_kobj,
941 disk_kobj->name);
942 }
943
944 if (one_device)
945 return 0;
946
947 list_for_each_entry(one_device,
948 &fs_devices->devices, dev_list) {
949 if (!one_device->bdev)
950 continue;
951 disk = one_device->bdev->bd_part;
952 disk_kobj = &part_to_dev(disk)->kobj;
953
954 sysfs_remove_link(fs_devices->device_dir_kobj,
955 disk_kobj->name);
956 }
957
958 return 0;
959}
960
961int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs)
962{
963 if (!fs_devs->device_dir_kobj)
964 fs_devs->device_dir_kobj = kobject_create_and_add("devices",
965 &fs_devs->fsid_kobj);
966
967 if (!fs_devs->device_dir_kobj)
968 return -ENOMEM;
969
970 return 0;
971}
972
973int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices,
974 struct btrfs_device *one_device)
975{
976 int error = 0;
977 struct btrfs_device *dev;
978
979 list_for_each_entry(dev, &fs_devices->devices, dev_list) {
980 struct hd_struct *disk;
981 struct kobject *disk_kobj;
982
983 if (!dev->bdev)
984 continue;
985
986 if (one_device && one_device != dev)
987 continue;
988
989 disk = dev->bdev->bd_part;
990 disk_kobj = &part_to_dev(disk)->kobj;
991
992 error = sysfs_create_link(fs_devices->device_dir_kobj,
993 disk_kobj, disk_kobj->name);
994 if (error)
995 break;
996 }
997
998 return error;
999}
1000
1001void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1002{
1003 int ret;
1004
1005 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1006 if (ret)
1007 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1008 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1009 &disk_to_dev(bdev->bd_disk)->kobj);
1010}
1011
1012void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices,
1013 const u8 *fsid)
1014{
1015 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1016
1017 /*
1018 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1019 * directory
1020 */
1021 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fsid);
1022 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1023 btrfs_warn(fs_devices->fs_info,
1024 "sysfs: failed to create fsid for sprout");
1025}
1026
1027/* /sys/fs/btrfs/ entry */
1028static struct kset *btrfs_kset;
1029
1030/*
1031 * Can be called by the device discovery thread.
1032 * And parent can be specified for seed device
1033 */
1034int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs,
1035 struct kobject *parent)
1036{
1037 int error;
1038
1039 init_completion(&fs_devs->kobj_unregister);
1040 fs_devs->fsid_kobj.kset = btrfs_kset;
1041 error = kobject_init_and_add(&fs_devs->fsid_kobj,
1042 &btrfs_ktype, parent, "%pU", fs_devs->fsid);
1043 if (error) {
1044 kobject_put(&fs_devs->fsid_kobj);
1045 return error;
1046 }
1047
1048 return 0;
1049}
1050
1051int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1052{
1053 int error;
1054 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1055 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1056
1057 btrfs_set_fs_info_ptr(fs_info);
1058
1059 error = btrfs_sysfs_add_device_link(fs_devs, NULL);
1060 if (error)
1061 return error;
1062
1063 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1064 if (error) {
1065 btrfs_sysfs_rm_device_link(fs_devs, NULL);
1066 return error;
1067 }
1068
1069 error = sysfs_create_group(fsid_kobj,
1070 &btrfs_feature_attr_group);
1071 if (error)
1072 goto failure;
1073
1074#ifdef CONFIG_BTRFS_DEBUG
1075 error = sysfs_create_group(fsid_kobj,
1076 &btrfs_debug_feature_attr_group);
1077 if (error)
1078 goto failure;
1079#endif
1080
1081 error = addrm_unknown_feature_attrs(fs_info, true);
1082 if (error)
1083 goto failure;
1084
1085 fs_info->space_info_kobj = kobject_create_and_add("allocation",
1086 fsid_kobj);
1087 if (!fs_info->space_info_kobj) {
1088 error = -ENOMEM;
1089 goto failure;
1090 }
1091
1092 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
1093 if (error)
1094 goto failure;
1095
1096 return 0;
1097failure:
1098 btrfs_sysfs_remove_mounted(fs_info);
1099 return error;
1100}
1101
1102
1103/*
1104 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
1105 * values in superblock. Call after any changes to incompat/compat_ro flags
1106 */
1107void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
1108 u64 bit, enum btrfs_feature_set set)
1109{
1110 struct btrfs_fs_devices *fs_devs;
1111 struct kobject *fsid_kobj;
1112 u64 features;
1113 int ret;
1114
1115 if (!fs_info)
1116 return;
1117
1118 features = get_features(fs_info, set);
1119 ASSERT(bit & supported_feature_masks[set]);
1120
1121 fs_devs = fs_info->fs_devices;
1122 fsid_kobj = &fs_devs->fsid_kobj;
1123
1124 if (!fsid_kobj->state_initialized)
1125 return;
1126
1127 /*
1128 * FIXME: this is too heavy to update just one value, ideally we'd like
1129 * to use sysfs_update_group but some refactoring is needed first.
1130 */
1131 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1132 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
1133}
1134
1135int __init btrfs_init_sysfs(void)
1136{
1137 int ret;
1138
1139 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
1140 if (!btrfs_kset)
1141 return -ENOMEM;
1142
1143 init_feature_attrs();
1144 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1145 if (ret)
1146 goto out2;
1147 ret = sysfs_merge_group(&btrfs_kset->kobj,
1148 &btrfs_static_feature_attr_group);
1149 if (ret)
1150 goto out_remove_group;
1151
1152#ifdef CONFIG_BTRFS_DEBUG
1153 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1154 if (ret)
1155 goto out2;
1156#endif
1157
1158 return 0;
1159
1160out_remove_group:
1161 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1162out2:
1163 kset_unregister(btrfs_kset);
1164
1165 return ret;
1166}
1167
1168void __cold btrfs_exit_sysfs(void)
1169{
1170 sysfs_unmerge_group(&btrfs_kset->kobj,
1171 &btrfs_static_feature_attr_group);
1172 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1173 kset_unregister(btrfs_kset);
1174}
1175
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 <crypto/hash.h>
13
14#include "ctree.h"
15#include "discard.h"
16#include "disk-io.h"
17#include "send.h"
18#include "transaction.h"
19#include "sysfs.h"
20#include "volumes.h"
21#include "space-info.h"
22#include "block-group.h"
23#include "qgroup.h"
24
25struct btrfs_feature_attr {
26 struct kobj_attribute kobj_attr;
27 enum btrfs_feature_set feature_set;
28 u64 feature_bit;
29};
30
31/* For raid type sysfs entries */
32struct raid_kobject {
33 u64 flags;
34 struct kobject kobj;
35};
36
37#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
38{ \
39 .attr = { .name = __stringify(_name), .mode = _mode }, \
40 .show = _show, \
41 .store = _store, \
42}
43
44#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
45 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
46 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
47
48#define BTRFS_ATTR(_prefix, _name, _show) \
49 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
50 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
51
52#define BTRFS_ATTR_PTR(_prefix, _name) \
53 (&btrfs_attr_##_prefix##_##_name.attr)
54
55#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
56static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
57 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
58 btrfs_feature_attr_show, \
59 btrfs_feature_attr_store), \
60 .feature_set = _feature_set, \
61 .feature_bit = _feature_prefix ##_## _feature_bit, \
62}
63#define BTRFS_FEAT_ATTR_PTR(_name) \
64 (&btrfs_attr_features_##_name.kobj_attr.attr)
65
66#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
67 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
68#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
69 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
70#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
71 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
72
73static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
74static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
75
76static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
77{
78 return container_of(a, struct btrfs_feature_attr, kobj_attr);
79}
80
81static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
82{
83 return container_of(attr, struct kobj_attribute, attr);
84}
85
86static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
87 struct attribute *attr)
88{
89 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
90}
91
92static u64 get_features(struct btrfs_fs_info *fs_info,
93 enum btrfs_feature_set set)
94{
95 struct btrfs_super_block *disk_super = fs_info->super_copy;
96 if (set == FEAT_COMPAT)
97 return btrfs_super_compat_flags(disk_super);
98 else if (set == FEAT_COMPAT_RO)
99 return btrfs_super_compat_ro_flags(disk_super);
100 else
101 return btrfs_super_incompat_flags(disk_super);
102}
103
104static void set_features(struct btrfs_fs_info *fs_info,
105 enum btrfs_feature_set set, u64 features)
106{
107 struct btrfs_super_block *disk_super = fs_info->super_copy;
108 if (set == FEAT_COMPAT)
109 btrfs_set_super_compat_flags(disk_super, features);
110 else if (set == FEAT_COMPAT_RO)
111 btrfs_set_super_compat_ro_flags(disk_super, features);
112 else
113 btrfs_set_super_incompat_flags(disk_super, features);
114}
115
116static int can_modify_feature(struct btrfs_feature_attr *fa)
117{
118 int val = 0;
119 u64 set, clear;
120 switch (fa->feature_set) {
121 case FEAT_COMPAT:
122 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
123 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
124 break;
125 case FEAT_COMPAT_RO:
126 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
127 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
128 break;
129 case FEAT_INCOMPAT:
130 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
131 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
132 break;
133 default:
134 pr_warn("btrfs: sysfs: unknown feature set %d\n",
135 fa->feature_set);
136 return 0;
137 }
138
139 if (set & fa->feature_bit)
140 val |= 1;
141 if (clear & fa->feature_bit)
142 val |= 2;
143
144 return val;
145}
146
147static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
148 struct kobj_attribute *a, char *buf)
149{
150 int val = 0;
151 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
152 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
153 if (fs_info) {
154 u64 features = get_features(fs_info, fa->feature_set);
155 if (features & fa->feature_bit)
156 val = 1;
157 } else
158 val = can_modify_feature(fa);
159
160 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
161}
162
163static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
164 struct kobj_attribute *a,
165 const char *buf, size_t count)
166{
167 struct btrfs_fs_info *fs_info;
168 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
169 u64 features, set, clear;
170 unsigned long val;
171 int ret;
172
173 fs_info = to_fs_info(kobj);
174 if (!fs_info)
175 return -EPERM;
176
177 if (sb_rdonly(fs_info->sb))
178 return -EROFS;
179
180 ret = kstrtoul(skip_spaces(buf), 0, &val);
181 if (ret)
182 return ret;
183
184 if (fa->feature_set == FEAT_COMPAT) {
185 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
186 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
187 } else if (fa->feature_set == FEAT_COMPAT_RO) {
188 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
189 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
190 } else {
191 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
192 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
193 }
194
195 features = get_features(fs_info, fa->feature_set);
196
197 /* Nothing to do */
198 if ((val && (features & fa->feature_bit)) ||
199 (!val && !(features & fa->feature_bit)))
200 return count;
201
202 if ((val && !(set & fa->feature_bit)) ||
203 (!val && !(clear & fa->feature_bit))) {
204 btrfs_info(fs_info,
205 "%sabling feature %s on mounted fs is not supported.",
206 val ? "En" : "Dis", fa->kobj_attr.attr.name);
207 return -EPERM;
208 }
209
210 btrfs_info(fs_info, "%s %s feature flag",
211 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
212
213 spin_lock(&fs_info->super_lock);
214 features = get_features(fs_info, fa->feature_set);
215 if (val)
216 features |= fa->feature_bit;
217 else
218 features &= ~fa->feature_bit;
219 set_features(fs_info, fa->feature_set, features);
220 spin_unlock(&fs_info->super_lock);
221
222 /*
223 * We don't want to do full transaction commit from inside sysfs
224 */
225 btrfs_set_pending(fs_info, COMMIT);
226 wake_up_process(fs_info->transaction_kthread);
227
228 return count;
229}
230
231static umode_t btrfs_feature_visible(struct kobject *kobj,
232 struct attribute *attr, int unused)
233{
234 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
235 umode_t mode = attr->mode;
236
237 if (fs_info) {
238 struct btrfs_feature_attr *fa;
239 u64 features;
240
241 fa = attr_to_btrfs_feature_attr(attr);
242 features = get_features(fs_info, fa->feature_set);
243
244 if (can_modify_feature(fa))
245 mode |= S_IWUSR;
246 else if (!(features & fa->feature_bit))
247 mode = 0;
248 }
249
250 return mode;
251}
252
253BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
254BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
255BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
256BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
257BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
258BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
259BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
260BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
261BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
262BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
263BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
264BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
265BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
266/* Remove once support for zoned allocation is feature complete */
267#ifdef CONFIG_BTRFS_DEBUG
268BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
269#endif
270
271static struct attribute *btrfs_supported_feature_attrs[] = {
272 BTRFS_FEAT_ATTR_PTR(mixed_backref),
273 BTRFS_FEAT_ATTR_PTR(default_subvol),
274 BTRFS_FEAT_ATTR_PTR(mixed_groups),
275 BTRFS_FEAT_ATTR_PTR(compress_lzo),
276 BTRFS_FEAT_ATTR_PTR(compress_zstd),
277 BTRFS_FEAT_ATTR_PTR(big_metadata),
278 BTRFS_FEAT_ATTR_PTR(extended_iref),
279 BTRFS_FEAT_ATTR_PTR(raid56),
280 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
281 BTRFS_FEAT_ATTR_PTR(no_holes),
282 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
283 BTRFS_FEAT_ATTR_PTR(free_space_tree),
284 BTRFS_FEAT_ATTR_PTR(raid1c34),
285#ifdef CONFIG_BTRFS_DEBUG
286 BTRFS_FEAT_ATTR_PTR(zoned),
287#endif
288 NULL
289};
290
291/*
292 * Features which depend on feature bits and may differ between each fs.
293 *
294 * /sys/fs/btrfs/features lists all available features of this kernel while
295 * /sys/fs/btrfs/UUID/features shows features of the fs which are enabled or
296 * can be changed online.
297 */
298static const struct attribute_group btrfs_feature_attr_group = {
299 .name = "features",
300 .is_visible = btrfs_feature_visible,
301 .attrs = btrfs_supported_feature_attrs,
302};
303
304static ssize_t rmdir_subvol_show(struct kobject *kobj,
305 struct kobj_attribute *ka, char *buf)
306{
307 return scnprintf(buf, PAGE_SIZE, "0\n");
308}
309BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
310
311static ssize_t supported_checksums_show(struct kobject *kobj,
312 struct kobj_attribute *a, char *buf)
313{
314 ssize_t ret = 0;
315 int i;
316
317 for (i = 0; i < btrfs_get_num_csums(); i++) {
318 /*
319 * This "trick" only works as long as 'enum btrfs_csum_type' has
320 * no holes in it
321 */
322 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
323 (i == 0 ? "" : " "), btrfs_super_csum_name(i));
324
325 }
326
327 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
328 return ret;
329}
330BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
331
332static ssize_t send_stream_version_show(struct kobject *kobj,
333 struct kobj_attribute *ka, char *buf)
334{
335 return snprintf(buf, PAGE_SIZE, "%d\n", BTRFS_SEND_STREAM_VERSION);
336}
337BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
338
339static const char *rescue_opts[] = {
340 "usebackuproot",
341 "nologreplay",
342 "ignorebadroots",
343 "ignoredatacsums",
344 "all",
345};
346
347static ssize_t supported_rescue_options_show(struct kobject *kobj,
348 struct kobj_attribute *a,
349 char *buf)
350{
351 ssize_t ret = 0;
352 int i;
353
354 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
355 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
356 (i ? " " : ""), rescue_opts[i]);
357 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
358 return ret;
359}
360BTRFS_ATTR(static_feature, supported_rescue_options,
361 supported_rescue_options_show);
362
363static ssize_t supported_sectorsizes_show(struct kobject *kobj,
364 struct kobj_attribute *a,
365 char *buf)
366{
367 ssize_t ret = 0;
368
369 /* Only sectorsize == PAGE_SIZE is now supported */
370 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%lu\n", PAGE_SIZE);
371
372 return ret;
373}
374BTRFS_ATTR(static_feature, supported_sectorsizes,
375 supported_sectorsizes_show);
376
377static struct attribute *btrfs_supported_static_feature_attrs[] = {
378 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
379 BTRFS_ATTR_PTR(static_feature, supported_checksums),
380 BTRFS_ATTR_PTR(static_feature, send_stream_version),
381 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
382 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
383 NULL
384};
385
386/*
387 * Features which only depend on kernel version.
388 *
389 * These are listed in /sys/fs/btrfs/features along with
390 * btrfs_feature_attr_group
391 */
392static const struct attribute_group btrfs_static_feature_attr_group = {
393 .name = "features",
394 .attrs = btrfs_supported_static_feature_attrs,
395};
396
397#ifdef CONFIG_BTRFS_DEBUG
398
399/*
400 * Discard statistics and tunables
401 */
402#define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent)
403
404static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
405 struct kobj_attribute *a,
406 char *buf)
407{
408 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
409
410 return scnprintf(buf, PAGE_SIZE, "%lld\n",
411 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
412}
413BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
414
415static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
416 struct kobj_attribute *a,
417 char *buf)
418{
419 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
420
421 return scnprintf(buf, PAGE_SIZE, "%d\n",
422 atomic_read(&fs_info->discard_ctl.discardable_extents));
423}
424BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
425
426static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
427 struct kobj_attribute *a,
428 char *buf)
429{
430 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
431
432 return scnprintf(buf, PAGE_SIZE, "%llu\n",
433 fs_info->discard_ctl.discard_bitmap_bytes);
434}
435BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
436
437static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
438 struct kobj_attribute *a,
439 char *buf)
440{
441 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
442
443 return scnprintf(buf, PAGE_SIZE, "%lld\n",
444 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
445}
446BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
447
448static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
449 struct kobj_attribute *a,
450 char *buf)
451{
452 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
453
454 return scnprintf(buf, PAGE_SIZE, "%llu\n",
455 fs_info->discard_ctl.discard_extent_bytes);
456}
457BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
458
459static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
460 struct kobj_attribute *a,
461 char *buf)
462{
463 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
464
465 return scnprintf(buf, PAGE_SIZE, "%u\n",
466 READ_ONCE(fs_info->discard_ctl.iops_limit));
467}
468
469static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
470 struct kobj_attribute *a,
471 const char *buf, size_t len)
472{
473 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
474 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
475 u32 iops_limit;
476 int ret;
477
478 ret = kstrtou32(buf, 10, &iops_limit);
479 if (ret)
480 return -EINVAL;
481
482 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
483 btrfs_discard_calc_delay(discard_ctl);
484 btrfs_discard_schedule_work(discard_ctl, true);
485 return len;
486}
487BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
488 btrfs_discard_iops_limit_store);
489
490static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
491 struct kobj_attribute *a,
492 char *buf)
493{
494 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
495
496 return scnprintf(buf, PAGE_SIZE, "%u\n",
497 READ_ONCE(fs_info->discard_ctl.kbps_limit));
498}
499
500static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
501 struct kobj_attribute *a,
502 const char *buf, size_t len)
503{
504 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
505 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
506 u32 kbps_limit;
507 int ret;
508
509 ret = kstrtou32(buf, 10, &kbps_limit);
510 if (ret)
511 return -EINVAL;
512
513 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
514 btrfs_discard_schedule_work(discard_ctl, true);
515 return len;
516}
517BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
518 btrfs_discard_kbps_limit_store);
519
520static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
521 struct kobj_attribute *a,
522 char *buf)
523{
524 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
525
526 return scnprintf(buf, PAGE_SIZE, "%llu\n",
527 READ_ONCE(fs_info->discard_ctl.max_discard_size));
528}
529
530static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
531 struct kobj_attribute *a,
532 const char *buf, size_t len)
533{
534 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
535 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
536 u64 max_discard_size;
537 int ret;
538
539 ret = kstrtou64(buf, 10, &max_discard_size);
540 if (ret)
541 return -EINVAL;
542
543 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
544
545 return len;
546}
547BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
548 btrfs_discard_max_discard_size_store);
549
550static const struct attribute *discard_debug_attrs[] = {
551 BTRFS_ATTR_PTR(discard, discardable_bytes),
552 BTRFS_ATTR_PTR(discard, discardable_extents),
553 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
554 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
555 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
556 BTRFS_ATTR_PTR(discard, iops_limit),
557 BTRFS_ATTR_PTR(discard, kbps_limit),
558 BTRFS_ATTR_PTR(discard, max_discard_size),
559 NULL,
560};
561
562/*
563 * Runtime debugging exported via sysfs
564 *
565 * /sys/fs/btrfs/debug - applies to module or all filesystems
566 * /sys/fs/btrfs/UUID - applies only to the given filesystem
567 */
568static const struct attribute *btrfs_debug_mount_attrs[] = {
569 NULL,
570};
571
572static struct attribute *btrfs_debug_feature_attrs[] = {
573 NULL
574};
575
576static const struct attribute_group btrfs_debug_feature_attr_group = {
577 .name = "debug",
578 .attrs = btrfs_debug_feature_attrs,
579};
580
581#endif
582
583static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
584{
585 u64 val;
586 if (lock)
587 spin_lock(lock);
588 val = *value_ptr;
589 if (lock)
590 spin_unlock(lock);
591 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
592}
593
594static ssize_t global_rsv_size_show(struct kobject *kobj,
595 struct kobj_attribute *ka, char *buf)
596{
597 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
598 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
599 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
600}
601BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
602
603static ssize_t global_rsv_reserved_show(struct kobject *kobj,
604 struct kobj_attribute *a, char *buf)
605{
606 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
607 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
608 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
609}
610BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
611
612#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
613#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
614
615static ssize_t raid_bytes_show(struct kobject *kobj,
616 struct kobj_attribute *attr, char *buf);
617BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
618BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
619
620static ssize_t raid_bytes_show(struct kobject *kobj,
621 struct kobj_attribute *attr, char *buf)
622
623{
624 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
625 struct btrfs_block_group *block_group;
626 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
627 u64 val = 0;
628
629 down_read(&sinfo->groups_sem);
630 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
631 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
632 val += block_group->length;
633 else
634 val += block_group->used;
635 }
636 up_read(&sinfo->groups_sem);
637 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
638}
639
640static struct attribute *raid_attrs[] = {
641 BTRFS_ATTR_PTR(raid, total_bytes),
642 BTRFS_ATTR_PTR(raid, used_bytes),
643 NULL
644};
645ATTRIBUTE_GROUPS(raid);
646
647static void release_raid_kobj(struct kobject *kobj)
648{
649 kfree(to_raid_kobj(kobj));
650}
651
652static struct kobj_type btrfs_raid_ktype = {
653 .sysfs_ops = &kobj_sysfs_ops,
654 .release = release_raid_kobj,
655 .default_groups = raid_groups,
656};
657
658#define SPACE_INFO_ATTR(field) \
659static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
660 struct kobj_attribute *a, \
661 char *buf) \
662{ \
663 struct btrfs_space_info *sinfo = to_space_info(kobj); \
664 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
665} \
666BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
667
668SPACE_INFO_ATTR(flags);
669SPACE_INFO_ATTR(total_bytes);
670SPACE_INFO_ATTR(bytes_used);
671SPACE_INFO_ATTR(bytes_pinned);
672SPACE_INFO_ATTR(bytes_reserved);
673SPACE_INFO_ATTR(bytes_may_use);
674SPACE_INFO_ATTR(bytes_readonly);
675SPACE_INFO_ATTR(bytes_zone_unusable);
676SPACE_INFO_ATTR(disk_used);
677SPACE_INFO_ATTR(disk_total);
678
679static struct attribute *space_info_attrs[] = {
680 BTRFS_ATTR_PTR(space_info, flags),
681 BTRFS_ATTR_PTR(space_info, total_bytes),
682 BTRFS_ATTR_PTR(space_info, bytes_used),
683 BTRFS_ATTR_PTR(space_info, bytes_pinned),
684 BTRFS_ATTR_PTR(space_info, bytes_reserved),
685 BTRFS_ATTR_PTR(space_info, bytes_may_use),
686 BTRFS_ATTR_PTR(space_info, bytes_readonly),
687 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
688 BTRFS_ATTR_PTR(space_info, disk_used),
689 BTRFS_ATTR_PTR(space_info, disk_total),
690 NULL,
691};
692ATTRIBUTE_GROUPS(space_info);
693
694static void space_info_release(struct kobject *kobj)
695{
696 struct btrfs_space_info *sinfo = to_space_info(kobj);
697 kfree(sinfo);
698}
699
700static struct kobj_type space_info_ktype = {
701 .sysfs_ops = &kobj_sysfs_ops,
702 .release = space_info_release,
703 .default_groups = space_info_groups,
704};
705
706static const struct attribute *allocation_attrs[] = {
707 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
708 BTRFS_ATTR_PTR(allocation, global_rsv_size),
709 NULL,
710};
711
712static ssize_t btrfs_label_show(struct kobject *kobj,
713 struct kobj_attribute *a, char *buf)
714{
715 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
716 char *label = fs_info->super_copy->label;
717 ssize_t ret;
718
719 spin_lock(&fs_info->super_lock);
720 ret = scnprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
721 spin_unlock(&fs_info->super_lock);
722
723 return ret;
724}
725
726static ssize_t btrfs_label_store(struct kobject *kobj,
727 struct kobj_attribute *a,
728 const char *buf, size_t len)
729{
730 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
731 size_t p_len;
732
733 if (!fs_info)
734 return -EPERM;
735
736 if (sb_rdonly(fs_info->sb))
737 return -EROFS;
738
739 /*
740 * p_len is the len until the first occurrence of either
741 * '\n' or '\0'
742 */
743 p_len = strcspn(buf, "\n");
744
745 if (p_len >= BTRFS_LABEL_SIZE)
746 return -EINVAL;
747
748 spin_lock(&fs_info->super_lock);
749 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
750 memcpy(fs_info->super_copy->label, buf, p_len);
751 spin_unlock(&fs_info->super_lock);
752
753 /*
754 * We don't want to do full transaction commit from inside sysfs
755 */
756 btrfs_set_pending(fs_info, COMMIT);
757 wake_up_process(fs_info->transaction_kthread);
758
759 return len;
760}
761BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
762
763static ssize_t btrfs_nodesize_show(struct kobject *kobj,
764 struct kobj_attribute *a, char *buf)
765{
766 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
767
768 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
769}
770
771BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
772
773static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
774 struct kobj_attribute *a, char *buf)
775{
776 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
777
778 return scnprintf(buf, PAGE_SIZE, "%u\n",
779 fs_info->super_copy->sectorsize);
780}
781
782BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
783
784static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
785 struct kobj_attribute *a, char *buf)
786{
787 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
788
789 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
790}
791
792BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
793
794static ssize_t quota_override_show(struct kobject *kobj,
795 struct kobj_attribute *a, char *buf)
796{
797 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
798 int quota_override;
799
800 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
801 return scnprintf(buf, PAGE_SIZE, "%d\n", quota_override);
802}
803
804static ssize_t quota_override_store(struct kobject *kobj,
805 struct kobj_attribute *a,
806 const char *buf, size_t len)
807{
808 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
809 unsigned long knob;
810 int err;
811
812 if (!fs_info)
813 return -EPERM;
814
815 if (!capable(CAP_SYS_RESOURCE))
816 return -EPERM;
817
818 err = kstrtoul(buf, 10, &knob);
819 if (err)
820 return err;
821 if (knob > 1)
822 return -EINVAL;
823
824 if (knob)
825 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
826 else
827 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
828
829 return len;
830}
831
832BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
833
834static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
835 struct kobj_attribute *a, char *buf)
836{
837 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
838
839 return scnprintf(buf, PAGE_SIZE, "%pU\n",
840 fs_info->fs_devices->metadata_uuid);
841}
842
843BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
844
845static ssize_t btrfs_checksum_show(struct kobject *kobj,
846 struct kobj_attribute *a, char *buf)
847{
848 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
849 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
850
851 return scnprintf(buf, PAGE_SIZE, "%s (%s)\n",
852 btrfs_super_csum_name(csum_type),
853 crypto_shash_driver_name(fs_info->csum_shash));
854}
855
856BTRFS_ATTR(, checksum, btrfs_checksum_show);
857
858static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
859 struct kobj_attribute *a, char *buf)
860{
861 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
862 const char *str;
863
864 switch (READ_ONCE(fs_info->exclusive_operation)) {
865 case BTRFS_EXCLOP_NONE:
866 str = "none\n";
867 break;
868 case BTRFS_EXCLOP_BALANCE:
869 str = "balance\n";
870 break;
871 case BTRFS_EXCLOP_DEV_ADD:
872 str = "device add\n";
873 break;
874 case BTRFS_EXCLOP_DEV_REMOVE:
875 str = "device remove\n";
876 break;
877 case BTRFS_EXCLOP_DEV_REPLACE:
878 str = "device replace\n";
879 break;
880 case BTRFS_EXCLOP_RESIZE:
881 str = "resize\n";
882 break;
883 case BTRFS_EXCLOP_SWAP_ACTIVATE:
884 str = "swap activate\n";
885 break;
886 default:
887 str = "UNKNOWN\n";
888 break;
889 }
890 return scnprintf(buf, PAGE_SIZE, "%s", str);
891}
892BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
893
894static ssize_t btrfs_generation_show(struct kobject *kobj,
895 struct kobj_attribute *a, char *buf)
896{
897 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
898
899 return scnprintf(buf, PAGE_SIZE, "%llu\n", fs_info->generation);
900}
901BTRFS_ATTR(, generation, btrfs_generation_show);
902
903/*
904 * Look for an exact string @string in @buffer with possible leading or
905 * trailing whitespace
906 */
907static bool strmatch(const char *buffer, const char *string)
908{
909 const size_t len = strlen(string);
910
911 /* Skip leading whitespace */
912 buffer = skip_spaces(buffer);
913
914 /* Match entire string, check if the rest is whitespace or empty */
915 if (strncmp(string, buffer, len) == 0 &&
916 strlen(skip_spaces(buffer + len)) == 0)
917 return true;
918
919 return false;
920}
921
922static const char * const btrfs_read_policy_name[] = { "pid" };
923
924static ssize_t btrfs_read_policy_show(struct kobject *kobj,
925 struct kobj_attribute *a, char *buf)
926{
927 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
928 ssize_t ret = 0;
929 int i;
930
931 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
932 if (fs_devices->read_policy == i)
933 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s[%s]",
934 (ret == 0 ? "" : " "),
935 btrfs_read_policy_name[i]);
936 else
937 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
938 (ret == 0 ? "" : " "),
939 btrfs_read_policy_name[i]);
940 }
941
942 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
943
944 return ret;
945}
946
947static ssize_t btrfs_read_policy_store(struct kobject *kobj,
948 struct kobj_attribute *a,
949 const char *buf, size_t len)
950{
951 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
952 int i;
953
954 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
955 if (strmatch(buf, btrfs_read_policy_name[i])) {
956 if (i != fs_devices->read_policy) {
957 fs_devices->read_policy = i;
958 btrfs_info(fs_devices->fs_info,
959 "read policy set to '%s'",
960 btrfs_read_policy_name[i]);
961 }
962 return len;
963 }
964 }
965
966 return -EINVAL;
967}
968BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
969
970static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
971 struct kobj_attribute *a,
972 char *buf)
973{
974 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
975 ssize_t ret;
976
977 ret = scnprintf(buf, PAGE_SIZE, "%d\n", fs_info->bg_reclaim_threshold);
978
979 return ret;
980}
981
982static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
983 struct kobj_attribute *a,
984 const char *buf, size_t len)
985{
986 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
987 int thresh;
988 int ret;
989
990 ret = kstrtoint(buf, 10, &thresh);
991 if (ret)
992 return ret;
993
994 if (thresh <= 50 || thresh > 100)
995 return -EINVAL;
996
997 fs_info->bg_reclaim_threshold = thresh;
998
999 return len;
1000}
1001BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
1002 btrfs_bg_reclaim_threshold_store);
1003
1004static const struct attribute *btrfs_attrs[] = {
1005 BTRFS_ATTR_PTR(, label),
1006 BTRFS_ATTR_PTR(, nodesize),
1007 BTRFS_ATTR_PTR(, sectorsize),
1008 BTRFS_ATTR_PTR(, clone_alignment),
1009 BTRFS_ATTR_PTR(, quota_override),
1010 BTRFS_ATTR_PTR(, metadata_uuid),
1011 BTRFS_ATTR_PTR(, checksum),
1012 BTRFS_ATTR_PTR(, exclusive_operation),
1013 BTRFS_ATTR_PTR(, generation),
1014 BTRFS_ATTR_PTR(, read_policy),
1015 BTRFS_ATTR_PTR(, bg_reclaim_threshold),
1016 NULL,
1017};
1018
1019static void btrfs_release_fsid_kobj(struct kobject *kobj)
1020{
1021 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
1022
1023 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
1024 complete(&fs_devs->kobj_unregister);
1025}
1026
1027static struct kobj_type btrfs_ktype = {
1028 .sysfs_ops = &kobj_sysfs_ops,
1029 .release = btrfs_release_fsid_kobj,
1030};
1031
1032static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
1033{
1034 if (kobj->ktype != &btrfs_ktype)
1035 return NULL;
1036 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
1037}
1038
1039static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1040{
1041 if (kobj->ktype != &btrfs_ktype)
1042 return NULL;
1043 return to_fs_devs(kobj)->fs_info;
1044}
1045
1046#define NUM_FEATURE_BITS 64
1047#define BTRFS_FEATURE_NAME_MAX 13
1048static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1049static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1050
1051static const u64 supported_feature_masks[FEAT_MAX] = {
1052 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1053 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1054 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1055};
1056
1057static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1058{
1059 int set;
1060
1061 for (set = 0; set < FEAT_MAX; set++) {
1062 int i;
1063 struct attribute *attrs[2];
1064 struct attribute_group agroup = {
1065 .name = "features",
1066 .attrs = attrs,
1067 };
1068 u64 features = get_features(fs_info, set);
1069 features &= ~supported_feature_masks[set];
1070
1071 if (!features)
1072 continue;
1073
1074 attrs[1] = NULL;
1075 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1076 struct btrfs_feature_attr *fa;
1077
1078 if (!(features & (1ULL << i)))
1079 continue;
1080
1081 fa = &btrfs_feature_attrs[set][i];
1082 attrs[0] = &fa->kobj_attr.attr;
1083 if (add) {
1084 int ret;
1085 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1086 &agroup);
1087 if (ret)
1088 return ret;
1089 } else
1090 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1091 &agroup);
1092 }
1093
1094 }
1095 return 0;
1096}
1097
1098static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1099{
1100 if (fs_devs->devinfo_kobj) {
1101 kobject_del(fs_devs->devinfo_kobj);
1102 kobject_put(fs_devs->devinfo_kobj);
1103 fs_devs->devinfo_kobj = NULL;
1104 }
1105
1106 if (fs_devs->devices_kobj) {
1107 kobject_del(fs_devs->devices_kobj);
1108 kobject_put(fs_devs->devices_kobj);
1109 fs_devs->devices_kobj = NULL;
1110 }
1111
1112 if (fs_devs->fsid_kobj.state_initialized) {
1113 kobject_del(&fs_devs->fsid_kobj);
1114 kobject_put(&fs_devs->fsid_kobj);
1115 wait_for_completion(&fs_devs->kobj_unregister);
1116 }
1117}
1118
1119/* when fs_devs is NULL it will remove all fsid kobject */
1120void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1121{
1122 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1123
1124 if (fs_devs) {
1125 __btrfs_sysfs_remove_fsid(fs_devs);
1126 return;
1127 }
1128
1129 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1130 __btrfs_sysfs_remove_fsid(fs_devs);
1131 }
1132}
1133
1134static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1135{
1136 struct btrfs_device *device;
1137 struct btrfs_fs_devices *seed;
1138
1139 list_for_each_entry(device, &fs_devices->devices, dev_list)
1140 btrfs_sysfs_remove_device(device);
1141
1142 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1143 list_for_each_entry(device, &seed->devices, dev_list)
1144 btrfs_sysfs_remove_device(device);
1145 }
1146}
1147
1148void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1149{
1150 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1151
1152 sysfs_remove_link(fsid_kobj, "bdi");
1153
1154 if (fs_info->space_info_kobj) {
1155 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1156 kobject_del(fs_info->space_info_kobj);
1157 kobject_put(fs_info->space_info_kobj);
1158 }
1159#ifdef CONFIG_BTRFS_DEBUG
1160 if (fs_info->discard_debug_kobj) {
1161 sysfs_remove_files(fs_info->discard_debug_kobj,
1162 discard_debug_attrs);
1163 kobject_del(fs_info->discard_debug_kobj);
1164 kobject_put(fs_info->discard_debug_kobj);
1165 }
1166 if (fs_info->debug_kobj) {
1167 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1168 kobject_del(fs_info->debug_kobj);
1169 kobject_put(fs_info->debug_kobj);
1170 }
1171#endif
1172 addrm_unknown_feature_attrs(fs_info, false);
1173 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1174 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1175 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1176}
1177
1178static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1179 [FEAT_COMPAT] = "compat",
1180 [FEAT_COMPAT_RO] = "compat_ro",
1181 [FEAT_INCOMPAT] = "incompat",
1182};
1183
1184const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1185{
1186 return btrfs_feature_set_names[set];
1187}
1188
1189char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1190{
1191 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1192 int len = 0;
1193 int i;
1194 char *str;
1195
1196 str = kmalloc(bufsize, GFP_KERNEL);
1197 if (!str)
1198 return str;
1199
1200 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1201 const char *name;
1202
1203 if (!(flags & (1ULL << i)))
1204 continue;
1205
1206 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1207 len += scnprintf(str + len, bufsize - len, "%s%s",
1208 len ? "," : "", name);
1209 }
1210
1211 return str;
1212}
1213
1214static void init_feature_attrs(void)
1215{
1216 struct btrfs_feature_attr *fa;
1217 int set, i;
1218
1219 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
1220 ARRAY_SIZE(btrfs_feature_attrs));
1221 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
1222 ARRAY_SIZE(btrfs_feature_attrs[0]));
1223
1224 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1225 memset(btrfs_unknown_feature_names, 0,
1226 sizeof(btrfs_unknown_feature_names));
1227
1228 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1229 struct btrfs_feature_attr *sfa;
1230 struct attribute *a = btrfs_supported_feature_attrs[i];
1231 int bit;
1232 sfa = attr_to_btrfs_feature_attr(a);
1233 bit = ilog2(sfa->feature_bit);
1234 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1235
1236 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1237 }
1238
1239 for (set = 0; set < FEAT_MAX; set++) {
1240 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1241 char *name = btrfs_unknown_feature_names[set][i];
1242 fa = &btrfs_feature_attrs[set][i];
1243
1244 if (fa->kobj_attr.attr.name)
1245 continue;
1246
1247 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1248 btrfs_feature_set_names[set], i);
1249
1250 fa->kobj_attr.attr.name = name;
1251 fa->kobj_attr.attr.mode = S_IRUGO;
1252 fa->feature_set = set;
1253 fa->feature_bit = 1ULL << i;
1254 }
1255 }
1256}
1257
1258/*
1259 * Create a sysfs entry for a given block group type at path
1260 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1261 */
1262void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1263{
1264 struct btrfs_fs_info *fs_info = cache->fs_info;
1265 struct btrfs_space_info *space_info = cache->space_info;
1266 struct raid_kobject *rkobj;
1267 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1268 unsigned int nofs_flag;
1269 int ret;
1270
1271 /*
1272 * Setup a NOFS context because kobject_add(), deep in its call chain,
1273 * does GFP_KERNEL allocations, and we are often called in a context
1274 * where if reclaim is triggered we can deadlock (we are either holding
1275 * a transaction handle or some lock required for a transaction
1276 * commit).
1277 */
1278 nofs_flag = memalloc_nofs_save();
1279
1280 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1281 if (!rkobj) {
1282 memalloc_nofs_restore(nofs_flag);
1283 btrfs_warn(cache->fs_info,
1284 "couldn't alloc memory for raid level kobject");
1285 return;
1286 }
1287
1288 rkobj->flags = cache->flags;
1289 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1290
1291 /*
1292 * We call this either on mount, or if we've created a block group for a
1293 * new index type while running (i.e. when restriping). The running
1294 * case is tricky because we could race with other threads, so we need
1295 * to have this check to make sure we didn't already init the kobject.
1296 *
1297 * We don't have to protect on the free side because it only happens on
1298 * unmount.
1299 */
1300 spin_lock(&space_info->lock);
1301 if (space_info->block_group_kobjs[index]) {
1302 spin_unlock(&space_info->lock);
1303 kobject_put(&rkobj->kobj);
1304 return;
1305 } else {
1306 space_info->block_group_kobjs[index] = &rkobj->kobj;
1307 }
1308 spin_unlock(&space_info->lock);
1309
1310 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1311 btrfs_bg_type_to_raid_name(rkobj->flags));
1312 memalloc_nofs_restore(nofs_flag);
1313 if (ret) {
1314 spin_lock(&space_info->lock);
1315 space_info->block_group_kobjs[index] = NULL;
1316 spin_unlock(&space_info->lock);
1317 kobject_put(&rkobj->kobj);
1318 btrfs_warn(fs_info,
1319 "failed to add kobject for block cache, ignoring");
1320 return;
1321 }
1322}
1323
1324/*
1325 * Remove sysfs directories for all block group types of a given space info and
1326 * the space info as well
1327 */
1328void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1329{
1330 int i;
1331
1332 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1333 struct kobject *kobj;
1334
1335 kobj = space_info->block_group_kobjs[i];
1336 space_info->block_group_kobjs[i] = NULL;
1337 if (kobj) {
1338 kobject_del(kobj);
1339 kobject_put(kobj);
1340 }
1341 }
1342 kobject_del(&space_info->kobj);
1343 kobject_put(&space_info->kobj);
1344}
1345
1346static const char *alloc_name(u64 flags)
1347{
1348 switch (flags) {
1349 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1350 return "mixed";
1351 case BTRFS_BLOCK_GROUP_METADATA:
1352 return "metadata";
1353 case BTRFS_BLOCK_GROUP_DATA:
1354 return "data";
1355 case BTRFS_BLOCK_GROUP_SYSTEM:
1356 return "system";
1357 default:
1358 WARN_ON(1);
1359 return "invalid-combination";
1360 }
1361}
1362
1363/*
1364 * Create a sysfs entry for a space info type at path
1365 * /sys/fs/btrfs/UUID/allocation/TYPE
1366 */
1367int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1368 struct btrfs_space_info *space_info)
1369{
1370 int ret;
1371
1372 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1373 fs_info->space_info_kobj, "%s",
1374 alloc_name(space_info->flags));
1375 if (ret) {
1376 kobject_put(&space_info->kobj);
1377 return ret;
1378 }
1379
1380 return 0;
1381}
1382
1383void btrfs_sysfs_remove_device(struct btrfs_device *device)
1384{
1385 struct kobject *devices_kobj;
1386
1387 /*
1388 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1389 * fs_info::fs_devices.
1390 */
1391 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1392 ASSERT(devices_kobj);
1393
1394 if (device->bdev)
1395 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1396
1397 if (device->devid_kobj.state_initialized) {
1398 kobject_del(&device->devid_kobj);
1399 kobject_put(&device->devid_kobj);
1400 wait_for_completion(&device->kobj_unregister);
1401 }
1402}
1403
1404static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1405 struct kobj_attribute *a,
1406 char *buf)
1407{
1408 int val;
1409 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1410 devid_kobj);
1411
1412 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1413
1414 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1415}
1416BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1417
1418static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1419 struct kobj_attribute *a, char *buf)
1420{
1421 int val;
1422 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1423 devid_kobj);
1424
1425 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1426
1427 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1428}
1429BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1430
1431static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1432 struct kobj_attribute *a,
1433 char *buf)
1434{
1435 int val;
1436 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1437 devid_kobj);
1438
1439 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1440
1441 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1442}
1443BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1444
1445static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
1446 struct kobj_attribute *a,
1447 char *buf)
1448{
1449 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1450 devid_kobj);
1451
1452 return scnprintf(buf, PAGE_SIZE, "%llu\n",
1453 READ_ONCE(device->scrub_speed_max));
1454}
1455
1456static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
1457 struct kobj_attribute *a,
1458 const char *buf, size_t len)
1459{
1460 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1461 devid_kobj);
1462 char *endptr;
1463 unsigned long long limit;
1464
1465 limit = memparse(buf, &endptr);
1466 WRITE_ONCE(device->scrub_speed_max, limit);
1467 return len;
1468}
1469BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show,
1470 btrfs_devinfo_scrub_speed_max_store);
1471
1472static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1473 struct kobj_attribute *a, char *buf)
1474{
1475 int val;
1476 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1477 devid_kobj);
1478
1479 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1480
1481 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1482}
1483BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1484
1485static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
1486 struct kobj_attribute *a, char *buf)
1487{
1488 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1489 devid_kobj);
1490
1491 if (!device->dev_stats_valid)
1492 return scnprintf(buf, PAGE_SIZE, "invalid\n");
1493
1494 /*
1495 * Print all at once so we get a snapshot of all values from the same
1496 * time. Keep them in sync and in order of definition of
1497 * btrfs_dev_stat_values.
1498 */
1499 return scnprintf(buf, PAGE_SIZE,
1500 "write_errs %d\n"
1501 "read_errs %d\n"
1502 "flush_errs %d\n"
1503 "corruption_errs %d\n"
1504 "generation_errs %d\n",
1505 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS),
1506 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS),
1507 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS),
1508 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS),
1509 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS));
1510}
1511BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show);
1512
1513static struct attribute *devid_attrs[] = {
1514 BTRFS_ATTR_PTR(devid, error_stats),
1515 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1516 BTRFS_ATTR_PTR(devid, missing),
1517 BTRFS_ATTR_PTR(devid, replace_target),
1518 BTRFS_ATTR_PTR(devid, scrub_speed_max),
1519 BTRFS_ATTR_PTR(devid, writeable),
1520 NULL
1521};
1522ATTRIBUTE_GROUPS(devid);
1523
1524static void btrfs_release_devid_kobj(struct kobject *kobj)
1525{
1526 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1527 devid_kobj);
1528
1529 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1530 complete(&device->kobj_unregister);
1531}
1532
1533static struct kobj_type devid_ktype = {
1534 .sysfs_ops = &kobj_sysfs_ops,
1535 .default_groups = devid_groups,
1536 .release = btrfs_release_devid_kobj,
1537};
1538
1539int btrfs_sysfs_add_device(struct btrfs_device *device)
1540{
1541 int ret;
1542 unsigned int nofs_flag;
1543 struct kobject *devices_kobj;
1544 struct kobject *devinfo_kobj;
1545
1546 /*
1547 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
1548 * for the seed fs_devices
1549 */
1550 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1551 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
1552 ASSERT(devices_kobj);
1553 ASSERT(devinfo_kobj);
1554
1555 nofs_flag = memalloc_nofs_save();
1556
1557 if (device->bdev) {
1558 struct kobject *disk_kobj = bdev_kobj(device->bdev);
1559
1560 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
1561 if (ret) {
1562 btrfs_warn(device->fs_info,
1563 "creating sysfs device link for devid %llu failed: %d",
1564 device->devid, ret);
1565 goto out;
1566 }
1567 }
1568
1569 init_completion(&device->kobj_unregister);
1570 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
1571 devinfo_kobj, "%llu", device->devid);
1572 if (ret) {
1573 kobject_put(&device->devid_kobj);
1574 btrfs_warn(device->fs_info,
1575 "devinfo init for devid %llu failed: %d",
1576 device->devid, ret);
1577 }
1578
1579out:
1580 memalloc_nofs_restore(nofs_flag);
1581 return ret;
1582}
1583
1584static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
1585{
1586 int ret;
1587 struct btrfs_device *device;
1588 struct btrfs_fs_devices *seed;
1589
1590 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1591 ret = btrfs_sysfs_add_device(device);
1592 if (ret)
1593 goto fail;
1594 }
1595
1596 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1597 list_for_each_entry(device, &seed->devices, dev_list) {
1598 ret = btrfs_sysfs_add_device(device);
1599 if (ret)
1600 goto fail;
1601 }
1602 }
1603
1604 return 0;
1605
1606fail:
1607 btrfs_sysfs_remove_fs_devices(fs_devices);
1608 return ret;
1609}
1610
1611void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1612{
1613 int ret;
1614
1615 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1616 if (ret)
1617 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1618 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1619 &disk_to_dev(bdev->bd_disk)->kobj);
1620}
1621
1622void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
1623
1624{
1625 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1626
1627 /*
1628 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1629 * directory
1630 */
1631 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
1632 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1633 btrfs_warn(fs_devices->fs_info,
1634 "sysfs: failed to create fsid for sprout");
1635}
1636
1637void btrfs_sysfs_update_devid(struct btrfs_device *device)
1638{
1639 char tmp[24];
1640
1641 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
1642
1643 if (kobject_rename(&device->devid_kobj, tmp))
1644 btrfs_warn(device->fs_devices->fs_info,
1645 "sysfs: failed to update devid for %llu",
1646 device->devid);
1647}
1648
1649/* /sys/fs/btrfs/ entry */
1650static struct kset *btrfs_kset;
1651
1652/*
1653 * Creates:
1654 * /sys/fs/btrfs/UUID
1655 *
1656 * Can be called by the device discovery thread.
1657 */
1658int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
1659{
1660 int error;
1661
1662 init_completion(&fs_devs->kobj_unregister);
1663 fs_devs->fsid_kobj.kset = btrfs_kset;
1664 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
1665 "%pU", fs_devs->fsid);
1666 if (error) {
1667 kobject_put(&fs_devs->fsid_kobj);
1668 return error;
1669 }
1670
1671 fs_devs->devices_kobj = kobject_create_and_add("devices",
1672 &fs_devs->fsid_kobj);
1673 if (!fs_devs->devices_kobj) {
1674 btrfs_err(fs_devs->fs_info,
1675 "failed to init sysfs device interface");
1676 btrfs_sysfs_remove_fsid(fs_devs);
1677 return -ENOMEM;
1678 }
1679
1680 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
1681 &fs_devs->fsid_kobj);
1682 if (!fs_devs->devinfo_kobj) {
1683 btrfs_err(fs_devs->fs_info,
1684 "failed to init sysfs devinfo kobject");
1685 btrfs_sysfs_remove_fsid(fs_devs);
1686 return -ENOMEM;
1687 }
1688
1689 return 0;
1690}
1691
1692int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1693{
1694 int error;
1695 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1696 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1697
1698 error = btrfs_sysfs_add_fs_devices(fs_devs);
1699 if (error)
1700 return error;
1701
1702 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1703 if (error) {
1704 btrfs_sysfs_remove_fs_devices(fs_devs);
1705 return error;
1706 }
1707
1708 error = sysfs_create_group(fsid_kobj,
1709 &btrfs_feature_attr_group);
1710 if (error)
1711 goto failure;
1712
1713#ifdef CONFIG_BTRFS_DEBUG
1714 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
1715 if (!fs_info->debug_kobj) {
1716 error = -ENOMEM;
1717 goto failure;
1718 }
1719
1720 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1721 if (error)
1722 goto failure;
1723
1724 /* Discard directory */
1725 fs_info->discard_debug_kobj = kobject_create_and_add("discard",
1726 fs_info->debug_kobj);
1727 if (!fs_info->discard_debug_kobj) {
1728 error = -ENOMEM;
1729 goto failure;
1730 }
1731
1732 error = sysfs_create_files(fs_info->discard_debug_kobj,
1733 discard_debug_attrs);
1734 if (error)
1735 goto failure;
1736#endif
1737
1738 error = addrm_unknown_feature_attrs(fs_info, true);
1739 if (error)
1740 goto failure;
1741
1742 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
1743 if (error)
1744 goto failure;
1745
1746 fs_info->space_info_kobj = kobject_create_and_add("allocation",
1747 fsid_kobj);
1748 if (!fs_info->space_info_kobj) {
1749 error = -ENOMEM;
1750 goto failure;
1751 }
1752
1753 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
1754 if (error)
1755 goto failure;
1756
1757 return 0;
1758failure:
1759 btrfs_sysfs_remove_mounted(fs_info);
1760 return error;
1761}
1762
1763static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
1764{
1765 return to_fs_info(kobj->parent->parent);
1766}
1767
1768#define QGROUP_ATTR(_member, _show_name) \
1769static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
1770 struct kobj_attribute *a, \
1771 char *buf) \
1772{ \
1773 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1774 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1775 struct btrfs_qgroup, kobj); \
1776 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
1777} \
1778BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
1779
1780#define QGROUP_RSV_ATTR(_name, _type) \
1781static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
1782 struct kobj_attribute *a, \
1783 char *buf) \
1784{ \
1785 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1786 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1787 struct btrfs_qgroup, kobj); \
1788 return btrfs_show_u64(&qgroup->rsv.values[_type], \
1789 &fs_info->qgroup_lock, buf); \
1790} \
1791BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
1792
1793QGROUP_ATTR(rfer, referenced);
1794QGROUP_ATTR(excl, exclusive);
1795QGROUP_ATTR(max_rfer, max_referenced);
1796QGROUP_ATTR(max_excl, max_exclusive);
1797QGROUP_ATTR(lim_flags, limit_flags);
1798QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
1799QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
1800QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
1801
1802static struct attribute *qgroup_attrs[] = {
1803 BTRFS_ATTR_PTR(qgroup, referenced),
1804 BTRFS_ATTR_PTR(qgroup, exclusive),
1805 BTRFS_ATTR_PTR(qgroup, max_referenced),
1806 BTRFS_ATTR_PTR(qgroup, max_exclusive),
1807 BTRFS_ATTR_PTR(qgroup, limit_flags),
1808 BTRFS_ATTR_PTR(qgroup, rsv_data),
1809 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
1810 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
1811 NULL
1812};
1813ATTRIBUTE_GROUPS(qgroup);
1814
1815static void qgroup_release(struct kobject *kobj)
1816{
1817 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
1818
1819 memset(&qgroup->kobj, 0, sizeof(*kobj));
1820}
1821
1822static struct kobj_type qgroup_ktype = {
1823 .sysfs_ops = &kobj_sysfs_ops,
1824 .release = qgroup_release,
1825 .default_groups = qgroup_groups,
1826};
1827
1828int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
1829 struct btrfs_qgroup *qgroup)
1830{
1831 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
1832 int ret;
1833
1834 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1835 return 0;
1836 if (qgroup->kobj.state_initialized)
1837 return 0;
1838 if (!qgroups_kobj)
1839 return -EINVAL;
1840
1841 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
1842 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
1843 btrfs_qgroup_subvolid(qgroup->qgroupid));
1844 if (ret < 0)
1845 kobject_put(&qgroup->kobj);
1846
1847 return ret;
1848}
1849
1850void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
1851{
1852 struct btrfs_qgroup *qgroup;
1853 struct btrfs_qgroup *next;
1854
1855 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1856 return;
1857
1858 rbtree_postorder_for_each_entry_safe(qgroup, next,
1859 &fs_info->qgroup_tree, node)
1860 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1861 if (fs_info->qgroups_kobj) {
1862 kobject_del(fs_info->qgroups_kobj);
1863 kobject_put(fs_info->qgroups_kobj);
1864 fs_info->qgroups_kobj = NULL;
1865 }
1866}
1867
1868/* Called when qgroups get initialized, thus there is no need for locking */
1869int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
1870{
1871 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1872 struct btrfs_qgroup *qgroup;
1873 struct btrfs_qgroup *next;
1874 int ret = 0;
1875
1876 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1877 return 0;
1878
1879 ASSERT(fsid_kobj);
1880 if (fs_info->qgroups_kobj)
1881 return 0;
1882
1883 fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj);
1884 if (!fs_info->qgroups_kobj) {
1885 ret = -ENOMEM;
1886 goto out;
1887 }
1888 rbtree_postorder_for_each_entry_safe(qgroup, next,
1889 &fs_info->qgroup_tree, node) {
1890 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1891 if (ret < 0)
1892 goto out;
1893 }
1894
1895out:
1896 if (ret < 0)
1897 btrfs_sysfs_del_qgroups(fs_info);
1898 return ret;
1899}
1900
1901void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
1902 struct btrfs_qgroup *qgroup)
1903{
1904 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1905 return;
1906
1907 if (qgroup->kobj.state_initialized) {
1908 kobject_del(&qgroup->kobj);
1909 kobject_put(&qgroup->kobj);
1910 }
1911}
1912
1913/*
1914 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
1915 * values in superblock. Call after any changes to incompat/compat_ro flags
1916 */
1917void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
1918 u64 bit, enum btrfs_feature_set set)
1919{
1920 struct btrfs_fs_devices *fs_devs;
1921 struct kobject *fsid_kobj;
1922 u64 __maybe_unused features;
1923 int __maybe_unused ret;
1924
1925 if (!fs_info)
1926 return;
1927
1928 /*
1929 * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not
1930 * safe when called from some contexts (eg. balance)
1931 */
1932 features = get_features(fs_info, set);
1933 ASSERT(bit & supported_feature_masks[set]);
1934
1935 fs_devs = fs_info->fs_devices;
1936 fsid_kobj = &fs_devs->fsid_kobj;
1937
1938 if (!fsid_kobj->state_initialized)
1939 return;
1940
1941 /*
1942 * FIXME: this is too heavy to update just one value, ideally we'd like
1943 * to use sysfs_update_group but some refactoring is needed first.
1944 */
1945 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1946 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
1947}
1948
1949int __init btrfs_init_sysfs(void)
1950{
1951 int ret;
1952
1953 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
1954 if (!btrfs_kset)
1955 return -ENOMEM;
1956
1957 init_feature_attrs();
1958 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1959 if (ret)
1960 goto out2;
1961 ret = sysfs_merge_group(&btrfs_kset->kobj,
1962 &btrfs_static_feature_attr_group);
1963 if (ret)
1964 goto out_remove_group;
1965
1966#ifdef CONFIG_BTRFS_DEBUG
1967 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1968 if (ret)
1969 goto out2;
1970#endif
1971
1972 return 0;
1973
1974out_remove_group:
1975 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1976out2:
1977 kset_unregister(btrfs_kset);
1978
1979 return ret;
1980}
1981
1982void __cold btrfs_exit_sysfs(void)
1983{
1984 sysfs_unmerge_group(&btrfs_kset->kobj,
1985 &btrfs_static_feature_attr_group);
1986 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1987#ifdef CONFIG_BTRFS_DEBUG
1988 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1989#endif
1990 kset_unregister(btrfs_kset);
1991}
1992