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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#include "messages.h"
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#include "misc.h"
25#include "fs.h"
26#include "accessors.h"
27
28/*
29 * Structure name Path
30 * --------------------------------------------------------------------------
31 * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features
32 * btrfs_supported_feature_attrs /sys/fs/btrfs/features and
33 * /sys/fs/btrfs/<uuid>/features
34 * btrfs_attrs /sys/fs/btrfs/<uuid>
35 * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid>
36 * allocation_attrs /sys/fs/btrfs/<uuid>/allocation
37 * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>
38 * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>
39 * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>
40 * discard_attrs /sys/fs/btrfs/<uuid>/discard
41 *
42 * When built with BTRFS_CONFIG_DEBUG:
43 *
44 * btrfs_debug_feature_attrs /sys/fs/btrfs/debug
45 * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug
46 */
47
48struct btrfs_feature_attr {
49 struct kobj_attribute kobj_attr;
50 enum btrfs_feature_set feature_set;
51 u64 feature_bit;
52};
53
54/* For raid type sysfs entries */
55struct raid_kobject {
56 u64 flags;
57 struct kobject kobj;
58};
59
60#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
61{ \
62 .attr = { .name = __stringify(_name), .mode = _mode }, \
63 .show = _show, \
64 .store = _store, \
65}
66
67#define BTRFS_ATTR_W(_prefix, _name, _store) \
68 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
69 __INIT_KOBJ_ATTR(_name, 0200, NULL, _store)
70
71#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
72 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
73 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
74
75#define BTRFS_ATTR(_prefix, _name, _show) \
76 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
77 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
78
79#define BTRFS_ATTR_PTR(_prefix, _name) \
80 (&btrfs_attr_##_prefix##_##_name.attr)
81
82#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
83static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
84 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
85 btrfs_feature_attr_show, \
86 btrfs_feature_attr_store), \
87 .feature_set = _feature_set, \
88 .feature_bit = _feature_prefix ##_## _feature_bit, \
89}
90#define BTRFS_FEAT_ATTR_PTR(_name) \
91 (&btrfs_attr_features_##_name.kobj_attr.attr)
92
93#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
94 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
95#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
96 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
97#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
98 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
99
100static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
101static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
102static struct kobject *get_btrfs_kobj(struct kobject *kobj);
103
104static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
105{
106 return container_of(a, struct btrfs_feature_attr, kobj_attr);
107}
108
109static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
110{
111 return container_of(attr, struct kobj_attribute, attr);
112}
113
114static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
115 struct attribute *attr)
116{
117 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
118}
119
120static u64 get_features(struct btrfs_fs_info *fs_info,
121 enum btrfs_feature_set set)
122{
123 struct btrfs_super_block *disk_super = fs_info->super_copy;
124 if (set == FEAT_COMPAT)
125 return btrfs_super_compat_flags(disk_super);
126 else if (set == FEAT_COMPAT_RO)
127 return btrfs_super_compat_ro_flags(disk_super);
128 else
129 return btrfs_super_incompat_flags(disk_super);
130}
131
132static void set_features(struct btrfs_fs_info *fs_info,
133 enum btrfs_feature_set set, u64 features)
134{
135 struct btrfs_super_block *disk_super = fs_info->super_copy;
136 if (set == FEAT_COMPAT)
137 btrfs_set_super_compat_flags(disk_super, features);
138 else if (set == FEAT_COMPAT_RO)
139 btrfs_set_super_compat_ro_flags(disk_super, features);
140 else
141 btrfs_set_super_incompat_flags(disk_super, features);
142}
143
144static int can_modify_feature(struct btrfs_feature_attr *fa)
145{
146 int val = 0;
147 u64 set, clear;
148 switch (fa->feature_set) {
149 case FEAT_COMPAT:
150 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
151 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
152 break;
153 case FEAT_COMPAT_RO:
154 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
155 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
156 break;
157 case FEAT_INCOMPAT:
158 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
159 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
160 break;
161 default:
162 pr_warn("btrfs: sysfs: unknown feature set %d\n",
163 fa->feature_set);
164 return 0;
165 }
166
167 if (set & fa->feature_bit)
168 val |= 1;
169 if (clear & fa->feature_bit)
170 val |= 2;
171
172 return val;
173}
174
175static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
176 struct kobj_attribute *a, char *buf)
177{
178 int val = 0;
179 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
180 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
181 if (fs_info) {
182 u64 features = get_features(fs_info, fa->feature_set);
183 if (features & fa->feature_bit)
184 val = 1;
185 } else
186 val = can_modify_feature(fa);
187
188 return sysfs_emit(buf, "%d\n", val);
189}
190
191static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
192 struct kobj_attribute *a,
193 const char *buf, size_t count)
194{
195 struct btrfs_fs_info *fs_info;
196 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
197 u64 features, set, clear;
198 unsigned long val;
199 int ret;
200
201 fs_info = to_fs_info(kobj);
202 if (!fs_info)
203 return -EPERM;
204
205 if (sb_rdonly(fs_info->sb))
206 return -EROFS;
207
208 ret = kstrtoul(skip_spaces(buf), 0, &val);
209 if (ret)
210 return ret;
211
212 if (fa->feature_set == FEAT_COMPAT) {
213 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
214 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
215 } else if (fa->feature_set == FEAT_COMPAT_RO) {
216 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
217 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
218 } else {
219 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
220 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
221 }
222
223 features = get_features(fs_info, fa->feature_set);
224
225 /* Nothing to do */
226 if ((val && (features & fa->feature_bit)) ||
227 (!val && !(features & fa->feature_bit)))
228 return count;
229
230 if ((val && !(set & fa->feature_bit)) ||
231 (!val && !(clear & fa->feature_bit))) {
232 btrfs_info(fs_info,
233 "%sabling feature %s on mounted fs is not supported.",
234 val ? "En" : "Dis", fa->kobj_attr.attr.name);
235 return -EPERM;
236 }
237
238 btrfs_info(fs_info, "%s %s feature flag",
239 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
240
241 spin_lock(&fs_info->super_lock);
242 features = get_features(fs_info, fa->feature_set);
243 if (val)
244 features |= fa->feature_bit;
245 else
246 features &= ~fa->feature_bit;
247 set_features(fs_info, fa->feature_set, features);
248 spin_unlock(&fs_info->super_lock);
249
250 /*
251 * We don't want to do full transaction commit from inside sysfs
252 */
253 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
254 wake_up_process(fs_info->transaction_kthread);
255
256 return count;
257}
258
259static umode_t btrfs_feature_visible(struct kobject *kobj,
260 struct attribute *attr, int unused)
261{
262 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
263 umode_t mode = attr->mode;
264
265 if (fs_info) {
266 struct btrfs_feature_attr *fa;
267 u64 features;
268
269 fa = attr_to_btrfs_feature_attr(attr);
270 features = get_features(fs_info, fa->feature_set);
271
272 if (can_modify_feature(fa))
273 mode |= S_IWUSR;
274 else if (!(features & fa->feature_bit))
275 mode = 0;
276 }
277
278 return mode;
279}
280
281BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
282BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
283BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
284BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
285BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
286BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
287BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
288BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
289BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
290BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
291BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE);
292BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
293#ifdef CONFIG_BLK_DEV_ZONED
294BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
295#endif
296#ifdef CONFIG_BTRFS_DEBUG
297/* Remove once support for extent tree v2 is feature complete */
298BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2);
299#endif
300#ifdef CONFIG_FS_VERITY
301BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
302#endif
303
304/*
305 * Features which depend on feature bits and may differ between each fs.
306 *
307 * /sys/fs/btrfs/features - all available features implemented by this version
308 * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or
309 * can be changed on a mounted filesystem.
310 */
311static struct attribute *btrfs_supported_feature_attrs[] = {
312 BTRFS_FEAT_ATTR_PTR(default_subvol),
313 BTRFS_FEAT_ATTR_PTR(mixed_groups),
314 BTRFS_FEAT_ATTR_PTR(compress_lzo),
315 BTRFS_FEAT_ATTR_PTR(compress_zstd),
316 BTRFS_FEAT_ATTR_PTR(extended_iref),
317 BTRFS_FEAT_ATTR_PTR(raid56),
318 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
319 BTRFS_FEAT_ATTR_PTR(no_holes),
320 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
321 BTRFS_FEAT_ATTR_PTR(free_space_tree),
322 BTRFS_FEAT_ATTR_PTR(raid1c34),
323 BTRFS_FEAT_ATTR_PTR(block_group_tree),
324#ifdef CONFIG_BLK_DEV_ZONED
325 BTRFS_FEAT_ATTR_PTR(zoned),
326#endif
327#ifdef CONFIG_BTRFS_DEBUG
328 BTRFS_FEAT_ATTR_PTR(extent_tree_v2),
329#endif
330#ifdef CONFIG_FS_VERITY
331 BTRFS_FEAT_ATTR_PTR(verity),
332#endif
333 NULL
334};
335
336static const struct attribute_group btrfs_feature_attr_group = {
337 .name = "features",
338 .is_visible = btrfs_feature_visible,
339 .attrs = btrfs_supported_feature_attrs,
340};
341
342static ssize_t rmdir_subvol_show(struct kobject *kobj,
343 struct kobj_attribute *ka, char *buf)
344{
345 return sysfs_emit(buf, "0\n");
346}
347BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
348
349static ssize_t supported_checksums_show(struct kobject *kobj,
350 struct kobj_attribute *a, char *buf)
351{
352 ssize_t ret = 0;
353 int i;
354
355 for (i = 0; i < btrfs_get_num_csums(); i++) {
356 /*
357 * This "trick" only works as long as 'enum btrfs_csum_type' has
358 * no holes in it
359 */
360 ret += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "),
361 btrfs_super_csum_name(i));
362
363 }
364
365 ret += sysfs_emit_at(buf, ret, "\n");
366 return ret;
367}
368BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
369
370static ssize_t send_stream_version_show(struct kobject *kobj,
371 struct kobj_attribute *ka, char *buf)
372{
373 return sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION);
374}
375BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
376
377static const char *rescue_opts[] = {
378 "usebackuproot",
379 "nologreplay",
380 "ignorebadroots",
381 "ignoredatacsums",
382 "all",
383};
384
385static ssize_t supported_rescue_options_show(struct kobject *kobj,
386 struct kobj_attribute *a,
387 char *buf)
388{
389 ssize_t ret = 0;
390 int i;
391
392 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
393 ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]);
394 ret += sysfs_emit_at(buf, ret, "\n");
395 return ret;
396}
397BTRFS_ATTR(static_feature, supported_rescue_options,
398 supported_rescue_options_show);
399
400static ssize_t supported_sectorsizes_show(struct kobject *kobj,
401 struct kobj_attribute *a,
402 char *buf)
403{
404 ssize_t ret = 0;
405
406 /* An artificial limit to only support 4K and PAGE_SIZE */
407 if (PAGE_SIZE > SZ_4K)
408 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K);
409 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE);
410
411 return ret;
412}
413BTRFS_ATTR(static_feature, supported_sectorsizes,
414 supported_sectorsizes_show);
415
416/*
417 * Features which only depend on kernel version.
418 *
419 * These are listed in /sys/fs/btrfs/features along with
420 * btrfs_supported_feature_attrs.
421 */
422static struct attribute *btrfs_supported_static_feature_attrs[] = {
423 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
424 BTRFS_ATTR_PTR(static_feature, supported_checksums),
425 BTRFS_ATTR_PTR(static_feature, send_stream_version),
426 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
427 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
428 NULL
429};
430
431static const struct attribute_group btrfs_static_feature_attr_group = {
432 .name = "features",
433 .attrs = btrfs_supported_static_feature_attrs,
434};
435
436/*
437 * Discard statistics and tunables
438 */
439#define discard_to_fs_info(_kobj) to_fs_info(get_btrfs_kobj(_kobj))
440
441static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
442 struct kobj_attribute *a,
443 char *buf)
444{
445 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
446
447 return sysfs_emit(buf, "%lld\n",
448 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
449}
450BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
451
452static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
453 struct kobj_attribute *a,
454 char *buf)
455{
456 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
457
458 return sysfs_emit(buf, "%d\n",
459 atomic_read(&fs_info->discard_ctl.discardable_extents));
460}
461BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
462
463static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
464 struct kobj_attribute *a,
465 char *buf)
466{
467 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
468
469 return sysfs_emit(buf, "%llu\n",
470 fs_info->discard_ctl.discard_bitmap_bytes);
471}
472BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
473
474static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
475 struct kobj_attribute *a,
476 char *buf)
477{
478 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
479
480 return sysfs_emit(buf, "%lld\n",
481 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
482}
483BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
484
485static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
486 struct kobj_attribute *a,
487 char *buf)
488{
489 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
490
491 return sysfs_emit(buf, "%llu\n",
492 fs_info->discard_ctl.discard_extent_bytes);
493}
494BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
495
496static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
497 struct kobj_attribute *a,
498 char *buf)
499{
500 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
501
502 return sysfs_emit(buf, "%u\n",
503 READ_ONCE(fs_info->discard_ctl.iops_limit));
504}
505
506static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
507 struct kobj_attribute *a,
508 const char *buf, size_t len)
509{
510 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
511 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
512 u32 iops_limit;
513 int ret;
514
515 ret = kstrtou32(buf, 10, &iops_limit);
516 if (ret)
517 return -EINVAL;
518
519 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
520 btrfs_discard_calc_delay(discard_ctl);
521 btrfs_discard_schedule_work(discard_ctl, true);
522 return len;
523}
524BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
525 btrfs_discard_iops_limit_store);
526
527static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
528 struct kobj_attribute *a,
529 char *buf)
530{
531 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
532
533 return sysfs_emit(buf, "%u\n",
534 READ_ONCE(fs_info->discard_ctl.kbps_limit));
535}
536
537static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
538 struct kobj_attribute *a,
539 const char *buf, size_t len)
540{
541 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
542 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
543 u32 kbps_limit;
544 int ret;
545
546 ret = kstrtou32(buf, 10, &kbps_limit);
547 if (ret)
548 return -EINVAL;
549
550 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
551 btrfs_discard_schedule_work(discard_ctl, true);
552 return len;
553}
554BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
555 btrfs_discard_kbps_limit_store);
556
557static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
558 struct kobj_attribute *a,
559 char *buf)
560{
561 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
562
563 return sysfs_emit(buf, "%llu\n",
564 READ_ONCE(fs_info->discard_ctl.max_discard_size));
565}
566
567static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
568 struct kobj_attribute *a,
569 const char *buf, size_t len)
570{
571 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
572 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
573 u64 max_discard_size;
574 int ret;
575
576 ret = kstrtou64(buf, 10, &max_discard_size);
577 if (ret)
578 return -EINVAL;
579
580 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
581
582 return len;
583}
584BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
585 btrfs_discard_max_discard_size_store);
586
587/*
588 * Per-filesystem stats for discard (when mounted with discard=async).
589 *
590 * Path: /sys/fs/btrfs/<uuid>/discard/
591 */
592static const struct attribute *discard_attrs[] = {
593 BTRFS_ATTR_PTR(discard, discardable_bytes),
594 BTRFS_ATTR_PTR(discard, discardable_extents),
595 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
596 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
597 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
598 BTRFS_ATTR_PTR(discard, iops_limit),
599 BTRFS_ATTR_PTR(discard, kbps_limit),
600 BTRFS_ATTR_PTR(discard, max_discard_size),
601 NULL,
602};
603
604#ifdef CONFIG_BTRFS_DEBUG
605
606/*
607 * Per-filesystem runtime debugging exported via sysfs.
608 *
609 * Path: /sys/fs/btrfs/UUID/debug/
610 */
611static const struct attribute *btrfs_debug_mount_attrs[] = {
612 NULL,
613};
614
615/*
616 * Runtime debugging exported via sysfs, applies to all mounted filesystems.
617 *
618 * Path: /sys/fs/btrfs/debug
619 */
620static struct attribute *btrfs_debug_feature_attrs[] = {
621 NULL
622};
623
624static const struct attribute_group btrfs_debug_feature_attr_group = {
625 .name = "debug",
626 .attrs = btrfs_debug_feature_attrs,
627};
628
629#endif
630
631static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
632{
633 u64 val;
634 if (lock)
635 spin_lock(lock);
636 val = *value_ptr;
637 if (lock)
638 spin_unlock(lock);
639 return sysfs_emit(buf, "%llu\n", val);
640}
641
642static ssize_t global_rsv_size_show(struct kobject *kobj,
643 struct kobj_attribute *ka, char *buf)
644{
645 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
646 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
647 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
648}
649BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
650
651static ssize_t global_rsv_reserved_show(struct kobject *kobj,
652 struct kobj_attribute *a, char *buf)
653{
654 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
655 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
656 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
657}
658BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
659
660#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
661#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
662
663static ssize_t raid_bytes_show(struct kobject *kobj,
664 struct kobj_attribute *attr, char *buf);
665BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
666BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
667
668static ssize_t raid_bytes_show(struct kobject *kobj,
669 struct kobj_attribute *attr, char *buf)
670
671{
672 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
673 struct btrfs_block_group *block_group;
674 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
675 u64 val = 0;
676
677 down_read(&sinfo->groups_sem);
678 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
679 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
680 val += block_group->length;
681 else
682 val += block_group->used;
683 }
684 up_read(&sinfo->groups_sem);
685 return sysfs_emit(buf, "%llu\n", val);
686}
687
688/*
689 * Allocation information about block group profiles.
690 *
691 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/
692 */
693static struct attribute *raid_attrs[] = {
694 BTRFS_ATTR_PTR(raid, total_bytes),
695 BTRFS_ATTR_PTR(raid, used_bytes),
696 NULL
697};
698ATTRIBUTE_GROUPS(raid);
699
700static void release_raid_kobj(struct kobject *kobj)
701{
702 kfree(to_raid_kobj(kobj));
703}
704
705static struct kobj_type btrfs_raid_ktype = {
706 .sysfs_ops = &kobj_sysfs_ops,
707 .release = release_raid_kobj,
708 .default_groups = raid_groups,
709};
710
711#define SPACE_INFO_ATTR(field) \
712static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
713 struct kobj_attribute *a, \
714 char *buf) \
715{ \
716 struct btrfs_space_info *sinfo = to_space_info(kobj); \
717 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
718} \
719BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
720
721static ssize_t btrfs_chunk_size_show(struct kobject *kobj,
722 struct kobj_attribute *a, char *buf)
723{
724 struct btrfs_space_info *sinfo = to_space_info(kobj);
725
726 return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size));
727}
728
729/*
730 * Store new chunk size in space info. Can be called on a read-only filesystem.
731 *
732 * If the new chunk size value is larger than 10% of free space it is reduced
733 * to match that limit. Alignment must be to 256M and the system chunk size
734 * cannot be set.
735 */
736static ssize_t btrfs_chunk_size_store(struct kobject *kobj,
737 struct kobj_attribute *a,
738 const char *buf, size_t len)
739{
740 struct btrfs_space_info *space_info = to_space_info(kobj);
741 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
742 char *retptr;
743 u64 val;
744
745 if (!capable(CAP_SYS_ADMIN))
746 return -EPERM;
747
748 if (!fs_info->fs_devices)
749 return -EINVAL;
750
751 if (btrfs_is_zoned(fs_info))
752 return -EINVAL;
753
754 /* System block type must not be changed. */
755 if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
756 return -EPERM;
757
758 val = memparse(buf, &retptr);
759 /* There could be trailing '\n', also catch any typos after the value */
760 retptr = skip_spaces(retptr);
761 if (*retptr != 0 || val == 0)
762 return -EINVAL;
763
764 val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE);
765
766 /* Limit stripe size to 10% of available space. */
767 val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val);
768
769 /* Must be multiple of 256M. */
770 val &= ~((u64)SZ_256M - 1);
771
772 /* Must be at least 256M. */
773 if (val < SZ_256M)
774 return -EINVAL;
775
776 btrfs_update_space_info_chunk_size(space_info, val);
777
778 return len;
779}
780
781#ifdef CONFIG_BTRFS_DEBUG
782/*
783 * Request chunk allocation with current chunk size.
784 */
785static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj,
786 struct kobj_attribute *a,
787 const char *buf, size_t len)
788{
789 struct btrfs_space_info *space_info = to_space_info(kobj);
790 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
791 struct btrfs_trans_handle *trans;
792 bool val;
793 int ret;
794
795 if (!capable(CAP_SYS_ADMIN))
796 return -EPERM;
797
798 if (sb_rdonly(fs_info->sb))
799 return -EROFS;
800
801 ret = kstrtobool(buf, &val);
802 if (ret)
803 return ret;
804
805 if (!val)
806 return -EINVAL;
807
808 /*
809 * This is unsafe to be called from sysfs context and may cause
810 * unexpected problems.
811 */
812 trans = btrfs_start_transaction(fs_info->tree_root, 0);
813 if (IS_ERR(trans))
814 return PTR_ERR(trans);
815 ret = btrfs_force_chunk_alloc(trans, space_info->flags);
816 btrfs_end_transaction(trans);
817
818 if (ret == 1)
819 return len;
820
821 return -ENOSPC;
822}
823BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store);
824
825#endif
826
827SPACE_INFO_ATTR(flags);
828SPACE_INFO_ATTR(total_bytes);
829SPACE_INFO_ATTR(bytes_used);
830SPACE_INFO_ATTR(bytes_pinned);
831SPACE_INFO_ATTR(bytes_reserved);
832SPACE_INFO_ATTR(bytes_may_use);
833SPACE_INFO_ATTR(bytes_readonly);
834SPACE_INFO_ATTR(bytes_zone_unusable);
835SPACE_INFO_ATTR(disk_used);
836SPACE_INFO_ATTR(disk_total);
837BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store);
838
839static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj,
840 struct kobj_attribute *a,
841 char *buf)
842{
843 struct btrfs_space_info *space_info = to_space_info(kobj);
844
845 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->bg_reclaim_threshold));
846}
847
848static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj,
849 struct kobj_attribute *a,
850 const char *buf, size_t len)
851{
852 struct btrfs_space_info *space_info = to_space_info(kobj);
853 int thresh;
854 int ret;
855
856 ret = kstrtoint(buf, 10, &thresh);
857 if (ret)
858 return ret;
859
860 if (thresh < 0 || thresh > 100)
861 return -EINVAL;
862
863 WRITE_ONCE(space_info->bg_reclaim_threshold, thresh);
864
865 return len;
866}
867
868BTRFS_ATTR_RW(space_info, bg_reclaim_threshold,
869 btrfs_sinfo_bg_reclaim_threshold_show,
870 btrfs_sinfo_bg_reclaim_threshold_store);
871
872/*
873 * Allocation information about block group types.
874 *
875 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/
876 */
877static struct attribute *space_info_attrs[] = {
878 BTRFS_ATTR_PTR(space_info, flags),
879 BTRFS_ATTR_PTR(space_info, total_bytes),
880 BTRFS_ATTR_PTR(space_info, bytes_used),
881 BTRFS_ATTR_PTR(space_info, bytes_pinned),
882 BTRFS_ATTR_PTR(space_info, bytes_reserved),
883 BTRFS_ATTR_PTR(space_info, bytes_may_use),
884 BTRFS_ATTR_PTR(space_info, bytes_readonly),
885 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
886 BTRFS_ATTR_PTR(space_info, disk_used),
887 BTRFS_ATTR_PTR(space_info, disk_total),
888 BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold),
889 BTRFS_ATTR_PTR(space_info, chunk_size),
890#ifdef CONFIG_BTRFS_DEBUG
891 BTRFS_ATTR_PTR(space_info, force_chunk_alloc),
892#endif
893 NULL,
894};
895ATTRIBUTE_GROUPS(space_info);
896
897static void space_info_release(struct kobject *kobj)
898{
899 struct btrfs_space_info *sinfo = to_space_info(kobj);
900 kfree(sinfo);
901}
902
903static struct kobj_type space_info_ktype = {
904 .sysfs_ops = &kobj_sysfs_ops,
905 .release = space_info_release,
906 .default_groups = space_info_groups,
907};
908
909/*
910 * Allocation information about block groups.
911 *
912 * Path: /sys/fs/btrfs/<uuid>/allocation/
913 */
914static const struct attribute *allocation_attrs[] = {
915 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
916 BTRFS_ATTR_PTR(allocation, global_rsv_size),
917 NULL,
918};
919
920static ssize_t btrfs_label_show(struct kobject *kobj,
921 struct kobj_attribute *a, char *buf)
922{
923 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
924 char *label = fs_info->super_copy->label;
925 ssize_t ret;
926
927 spin_lock(&fs_info->super_lock);
928 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label);
929 spin_unlock(&fs_info->super_lock);
930
931 return ret;
932}
933
934static ssize_t btrfs_label_store(struct kobject *kobj,
935 struct kobj_attribute *a,
936 const char *buf, size_t len)
937{
938 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
939 size_t p_len;
940
941 if (!fs_info)
942 return -EPERM;
943
944 if (sb_rdonly(fs_info->sb))
945 return -EROFS;
946
947 /*
948 * p_len is the len until the first occurrence of either
949 * '\n' or '\0'
950 */
951 p_len = strcspn(buf, "\n");
952
953 if (p_len >= BTRFS_LABEL_SIZE)
954 return -EINVAL;
955
956 spin_lock(&fs_info->super_lock);
957 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
958 memcpy(fs_info->super_copy->label, buf, p_len);
959 spin_unlock(&fs_info->super_lock);
960
961 /*
962 * We don't want to do full transaction commit from inside sysfs
963 */
964 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
965 wake_up_process(fs_info->transaction_kthread);
966
967 return len;
968}
969BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
970
971static ssize_t btrfs_nodesize_show(struct kobject *kobj,
972 struct kobj_attribute *a, char *buf)
973{
974 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
975
976 return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize);
977}
978
979BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
980
981static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
982 struct kobj_attribute *a, char *buf)
983{
984 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
985
986 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
987}
988
989BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
990
991static ssize_t btrfs_commit_stats_show(struct kobject *kobj,
992 struct kobj_attribute *a, char *buf)
993{
994 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
995
996 return sysfs_emit(buf,
997 "commits %llu\n"
998 "last_commit_ms %llu\n"
999 "max_commit_ms %llu\n"
1000 "total_commit_ms %llu\n",
1001 fs_info->commit_stats.commit_count,
1002 div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC),
1003 div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC),
1004 div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC));
1005}
1006
1007static ssize_t btrfs_commit_stats_store(struct kobject *kobj,
1008 struct kobj_attribute *a,
1009 const char *buf, size_t len)
1010{
1011 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1012 unsigned long val;
1013 int ret;
1014
1015 if (!fs_info)
1016 return -EPERM;
1017
1018 if (!capable(CAP_SYS_RESOURCE))
1019 return -EPERM;
1020
1021 ret = kstrtoul(buf, 10, &val);
1022 if (ret)
1023 return ret;
1024 if (val)
1025 return -EINVAL;
1026
1027 WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0);
1028
1029 return len;
1030}
1031BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store);
1032
1033static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
1034 struct kobj_attribute *a, char *buf)
1035{
1036 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1037
1038 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
1039}
1040
1041BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
1042
1043static ssize_t quota_override_show(struct kobject *kobj,
1044 struct kobj_attribute *a, char *buf)
1045{
1046 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1047 int quota_override;
1048
1049 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1050 return sysfs_emit(buf, "%d\n", quota_override);
1051}
1052
1053static ssize_t quota_override_store(struct kobject *kobj,
1054 struct kobj_attribute *a,
1055 const char *buf, size_t len)
1056{
1057 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1058 unsigned long knob;
1059 int err;
1060
1061 if (!fs_info)
1062 return -EPERM;
1063
1064 if (!capable(CAP_SYS_RESOURCE))
1065 return -EPERM;
1066
1067 err = kstrtoul(buf, 10, &knob);
1068 if (err)
1069 return err;
1070 if (knob > 1)
1071 return -EINVAL;
1072
1073 if (knob)
1074 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1075 else
1076 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1077
1078 return len;
1079}
1080
1081BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
1082
1083static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
1084 struct kobj_attribute *a, char *buf)
1085{
1086 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1087
1088 return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid);
1089}
1090
1091BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
1092
1093static ssize_t btrfs_checksum_show(struct kobject *kobj,
1094 struct kobj_attribute *a, char *buf)
1095{
1096 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1097 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
1098
1099 return sysfs_emit(buf, "%s (%s)\n",
1100 btrfs_super_csum_name(csum_type),
1101 crypto_shash_driver_name(fs_info->csum_shash));
1102}
1103
1104BTRFS_ATTR(, checksum, btrfs_checksum_show);
1105
1106static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
1107 struct kobj_attribute *a, char *buf)
1108{
1109 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1110 const char *str;
1111
1112 switch (READ_ONCE(fs_info->exclusive_operation)) {
1113 case BTRFS_EXCLOP_NONE:
1114 str = "none\n";
1115 break;
1116 case BTRFS_EXCLOP_BALANCE:
1117 str = "balance\n";
1118 break;
1119 case BTRFS_EXCLOP_BALANCE_PAUSED:
1120 str = "balance paused\n";
1121 break;
1122 case BTRFS_EXCLOP_DEV_ADD:
1123 str = "device add\n";
1124 break;
1125 case BTRFS_EXCLOP_DEV_REMOVE:
1126 str = "device remove\n";
1127 break;
1128 case BTRFS_EXCLOP_DEV_REPLACE:
1129 str = "device replace\n";
1130 break;
1131 case BTRFS_EXCLOP_RESIZE:
1132 str = "resize\n";
1133 break;
1134 case BTRFS_EXCLOP_SWAP_ACTIVATE:
1135 str = "swap activate\n";
1136 break;
1137 default:
1138 str = "UNKNOWN\n";
1139 break;
1140 }
1141 return sysfs_emit(buf, "%s", str);
1142}
1143BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
1144
1145static ssize_t btrfs_generation_show(struct kobject *kobj,
1146 struct kobj_attribute *a, char *buf)
1147{
1148 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1149
1150 return sysfs_emit(buf, "%llu\n", fs_info->generation);
1151}
1152BTRFS_ATTR(, generation, btrfs_generation_show);
1153
1154static const char * const btrfs_read_policy_name[] = { "pid" };
1155
1156static ssize_t btrfs_read_policy_show(struct kobject *kobj,
1157 struct kobj_attribute *a, char *buf)
1158{
1159 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1160 ssize_t ret = 0;
1161 int i;
1162
1163 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1164 if (fs_devices->read_policy == i)
1165 ret += sysfs_emit_at(buf, ret, "%s[%s]",
1166 (ret == 0 ? "" : " "),
1167 btrfs_read_policy_name[i]);
1168 else
1169 ret += sysfs_emit_at(buf, ret, "%s%s",
1170 (ret == 0 ? "" : " "),
1171 btrfs_read_policy_name[i]);
1172 }
1173
1174 ret += sysfs_emit_at(buf, ret, "\n");
1175
1176 return ret;
1177}
1178
1179static ssize_t btrfs_read_policy_store(struct kobject *kobj,
1180 struct kobj_attribute *a,
1181 const char *buf, size_t len)
1182{
1183 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1184 int i;
1185
1186 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1187 if (sysfs_streq(buf, btrfs_read_policy_name[i])) {
1188 if (i != fs_devices->read_policy) {
1189 fs_devices->read_policy = i;
1190 btrfs_info(fs_devices->fs_info,
1191 "read policy set to '%s'",
1192 btrfs_read_policy_name[i]);
1193 }
1194 return len;
1195 }
1196 }
1197
1198 return -EINVAL;
1199}
1200BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
1201
1202static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
1203 struct kobj_attribute *a,
1204 char *buf)
1205{
1206 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1207
1208 return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
1209}
1210
1211static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
1212 struct kobj_attribute *a,
1213 const char *buf, size_t len)
1214{
1215 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1216 int thresh;
1217 int ret;
1218
1219 ret = kstrtoint(buf, 10, &thresh);
1220 if (ret)
1221 return ret;
1222
1223 if (thresh != 0 && (thresh <= 50 || thresh > 100))
1224 return -EINVAL;
1225
1226 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
1227
1228 return len;
1229}
1230BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
1231 btrfs_bg_reclaim_threshold_store);
1232
1233/*
1234 * Per-filesystem information and stats.
1235 *
1236 * Path: /sys/fs/btrfs/<uuid>/
1237 */
1238static const struct attribute *btrfs_attrs[] = {
1239 BTRFS_ATTR_PTR(, label),
1240 BTRFS_ATTR_PTR(, nodesize),
1241 BTRFS_ATTR_PTR(, sectorsize),
1242 BTRFS_ATTR_PTR(, clone_alignment),
1243 BTRFS_ATTR_PTR(, quota_override),
1244 BTRFS_ATTR_PTR(, metadata_uuid),
1245 BTRFS_ATTR_PTR(, checksum),
1246 BTRFS_ATTR_PTR(, exclusive_operation),
1247 BTRFS_ATTR_PTR(, generation),
1248 BTRFS_ATTR_PTR(, read_policy),
1249 BTRFS_ATTR_PTR(, bg_reclaim_threshold),
1250 BTRFS_ATTR_PTR(, commit_stats),
1251 NULL,
1252};
1253
1254static void btrfs_release_fsid_kobj(struct kobject *kobj)
1255{
1256 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
1257
1258 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
1259 complete(&fs_devs->kobj_unregister);
1260}
1261
1262static struct kobj_type btrfs_ktype = {
1263 .sysfs_ops = &kobj_sysfs_ops,
1264 .release = btrfs_release_fsid_kobj,
1265};
1266
1267static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
1268{
1269 if (kobj->ktype != &btrfs_ktype)
1270 return NULL;
1271 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
1272}
1273
1274static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1275{
1276 if (kobj->ktype != &btrfs_ktype)
1277 return NULL;
1278 return to_fs_devs(kobj)->fs_info;
1279}
1280
1281static struct kobject *get_btrfs_kobj(struct kobject *kobj)
1282{
1283 while (kobj) {
1284 if (kobj->ktype == &btrfs_ktype)
1285 return kobj;
1286 kobj = kobj->parent;
1287 }
1288 return NULL;
1289}
1290
1291#define NUM_FEATURE_BITS 64
1292#define BTRFS_FEATURE_NAME_MAX 13
1293static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1294static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1295
1296static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) ==
1297 ARRAY_SIZE(btrfs_feature_attrs));
1298static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) ==
1299 ARRAY_SIZE(btrfs_feature_attrs[0]));
1300
1301static const u64 supported_feature_masks[FEAT_MAX] = {
1302 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1303 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1304 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1305};
1306
1307static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1308{
1309 int set;
1310
1311 for (set = 0; set < FEAT_MAX; set++) {
1312 int i;
1313 struct attribute *attrs[2];
1314 struct attribute_group agroup = {
1315 .name = "features",
1316 .attrs = attrs,
1317 };
1318 u64 features = get_features(fs_info, set);
1319 features &= ~supported_feature_masks[set];
1320
1321 if (!features)
1322 continue;
1323
1324 attrs[1] = NULL;
1325 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1326 struct btrfs_feature_attr *fa;
1327
1328 if (!(features & (1ULL << i)))
1329 continue;
1330
1331 fa = &btrfs_feature_attrs[set][i];
1332 attrs[0] = &fa->kobj_attr.attr;
1333 if (add) {
1334 int ret;
1335 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1336 &agroup);
1337 if (ret)
1338 return ret;
1339 } else
1340 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1341 &agroup);
1342 }
1343
1344 }
1345 return 0;
1346}
1347
1348static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1349{
1350 if (fs_devs->devinfo_kobj) {
1351 kobject_del(fs_devs->devinfo_kobj);
1352 kobject_put(fs_devs->devinfo_kobj);
1353 fs_devs->devinfo_kobj = NULL;
1354 }
1355
1356 if (fs_devs->devices_kobj) {
1357 kobject_del(fs_devs->devices_kobj);
1358 kobject_put(fs_devs->devices_kobj);
1359 fs_devs->devices_kobj = NULL;
1360 }
1361
1362 if (fs_devs->fsid_kobj.state_initialized) {
1363 kobject_del(&fs_devs->fsid_kobj);
1364 kobject_put(&fs_devs->fsid_kobj);
1365 wait_for_completion(&fs_devs->kobj_unregister);
1366 }
1367}
1368
1369/* when fs_devs is NULL it will remove all fsid kobject */
1370void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1371{
1372 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1373
1374 if (fs_devs) {
1375 __btrfs_sysfs_remove_fsid(fs_devs);
1376 return;
1377 }
1378
1379 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1380 __btrfs_sysfs_remove_fsid(fs_devs);
1381 }
1382}
1383
1384static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1385{
1386 struct btrfs_device *device;
1387 struct btrfs_fs_devices *seed;
1388
1389 list_for_each_entry(device, &fs_devices->devices, dev_list)
1390 btrfs_sysfs_remove_device(device);
1391
1392 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1393 list_for_each_entry(device, &seed->devices, dev_list)
1394 btrfs_sysfs_remove_device(device);
1395 }
1396}
1397
1398void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1399{
1400 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1401
1402 sysfs_remove_link(fsid_kobj, "bdi");
1403
1404 if (fs_info->space_info_kobj) {
1405 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1406 kobject_del(fs_info->space_info_kobj);
1407 kobject_put(fs_info->space_info_kobj);
1408 }
1409 if (fs_info->discard_kobj) {
1410 sysfs_remove_files(fs_info->discard_kobj, discard_attrs);
1411 kobject_del(fs_info->discard_kobj);
1412 kobject_put(fs_info->discard_kobj);
1413 }
1414#ifdef CONFIG_BTRFS_DEBUG
1415 if (fs_info->debug_kobj) {
1416 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1417 kobject_del(fs_info->debug_kobj);
1418 kobject_put(fs_info->debug_kobj);
1419 }
1420#endif
1421 addrm_unknown_feature_attrs(fs_info, false);
1422 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1423 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1424 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1425}
1426
1427static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1428 [FEAT_COMPAT] = "compat",
1429 [FEAT_COMPAT_RO] = "compat_ro",
1430 [FEAT_INCOMPAT] = "incompat",
1431};
1432
1433const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1434{
1435 return btrfs_feature_set_names[set];
1436}
1437
1438char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1439{
1440 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1441 int len = 0;
1442 int i;
1443 char *str;
1444
1445 str = kmalloc(bufsize, GFP_KERNEL);
1446 if (!str)
1447 return str;
1448
1449 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1450 const char *name;
1451
1452 if (!(flags & (1ULL << i)))
1453 continue;
1454
1455 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1456 len += scnprintf(str + len, bufsize - len, "%s%s",
1457 len ? "," : "", name);
1458 }
1459
1460 return str;
1461}
1462
1463static void init_feature_attrs(void)
1464{
1465 struct btrfs_feature_attr *fa;
1466 int set, i;
1467
1468 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1469 memset(btrfs_unknown_feature_names, 0,
1470 sizeof(btrfs_unknown_feature_names));
1471
1472 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1473 struct btrfs_feature_attr *sfa;
1474 struct attribute *a = btrfs_supported_feature_attrs[i];
1475 int bit;
1476 sfa = attr_to_btrfs_feature_attr(a);
1477 bit = ilog2(sfa->feature_bit);
1478 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1479
1480 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1481 }
1482
1483 for (set = 0; set < FEAT_MAX; set++) {
1484 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1485 char *name = btrfs_unknown_feature_names[set][i];
1486 fa = &btrfs_feature_attrs[set][i];
1487
1488 if (fa->kobj_attr.attr.name)
1489 continue;
1490
1491 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1492 btrfs_feature_set_names[set], i);
1493
1494 fa->kobj_attr.attr.name = name;
1495 fa->kobj_attr.attr.mode = S_IRUGO;
1496 fa->feature_set = set;
1497 fa->feature_bit = 1ULL << i;
1498 }
1499 }
1500}
1501
1502/*
1503 * Create a sysfs entry for a given block group type at path
1504 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1505 */
1506void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1507{
1508 struct btrfs_fs_info *fs_info = cache->fs_info;
1509 struct btrfs_space_info *space_info = cache->space_info;
1510 struct raid_kobject *rkobj;
1511 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1512 unsigned int nofs_flag;
1513 int ret;
1514
1515 /*
1516 * Setup a NOFS context because kobject_add(), deep in its call chain,
1517 * does GFP_KERNEL allocations, and we are often called in a context
1518 * where if reclaim is triggered we can deadlock (we are either holding
1519 * a transaction handle or some lock required for a transaction
1520 * commit).
1521 */
1522 nofs_flag = memalloc_nofs_save();
1523
1524 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1525 if (!rkobj) {
1526 memalloc_nofs_restore(nofs_flag);
1527 btrfs_warn(cache->fs_info,
1528 "couldn't alloc memory for raid level kobject");
1529 return;
1530 }
1531
1532 rkobj->flags = cache->flags;
1533 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1534
1535 /*
1536 * We call this either on mount, or if we've created a block group for a
1537 * new index type while running (i.e. when restriping). The running
1538 * case is tricky because we could race with other threads, so we need
1539 * to have this check to make sure we didn't already init the kobject.
1540 *
1541 * We don't have to protect on the free side because it only happens on
1542 * unmount.
1543 */
1544 spin_lock(&space_info->lock);
1545 if (space_info->block_group_kobjs[index]) {
1546 spin_unlock(&space_info->lock);
1547 kobject_put(&rkobj->kobj);
1548 return;
1549 } else {
1550 space_info->block_group_kobjs[index] = &rkobj->kobj;
1551 }
1552 spin_unlock(&space_info->lock);
1553
1554 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1555 btrfs_bg_type_to_raid_name(rkobj->flags));
1556 memalloc_nofs_restore(nofs_flag);
1557 if (ret) {
1558 spin_lock(&space_info->lock);
1559 space_info->block_group_kobjs[index] = NULL;
1560 spin_unlock(&space_info->lock);
1561 kobject_put(&rkobj->kobj);
1562 btrfs_warn(fs_info,
1563 "failed to add kobject for block cache, ignoring");
1564 return;
1565 }
1566}
1567
1568/*
1569 * Remove sysfs directories for all block group types of a given space info and
1570 * the space info as well
1571 */
1572void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1573{
1574 int i;
1575
1576 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1577 struct kobject *kobj;
1578
1579 kobj = space_info->block_group_kobjs[i];
1580 space_info->block_group_kobjs[i] = NULL;
1581 if (kobj) {
1582 kobject_del(kobj);
1583 kobject_put(kobj);
1584 }
1585 }
1586 kobject_del(&space_info->kobj);
1587 kobject_put(&space_info->kobj);
1588}
1589
1590static const char *alloc_name(u64 flags)
1591{
1592 switch (flags) {
1593 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1594 return "mixed";
1595 case BTRFS_BLOCK_GROUP_METADATA:
1596 return "metadata";
1597 case BTRFS_BLOCK_GROUP_DATA:
1598 return "data";
1599 case BTRFS_BLOCK_GROUP_SYSTEM:
1600 return "system";
1601 default:
1602 WARN_ON(1);
1603 return "invalid-combination";
1604 }
1605}
1606
1607/*
1608 * Create a sysfs entry for a space info type at path
1609 * /sys/fs/btrfs/UUID/allocation/TYPE
1610 */
1611int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1612 struct btrfs_space_info *space_info)
1613{
1614 int ret;
1615
1616 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1617 fs_info->space_info_kobj, "%s",
1618 alloc_name(space_info->flags));
1619 if (ret) {
1620 kobject_put(&space_info->kobj);
1621 return ret;
1622 }
1623
1624 return 0;
1625}
1626
1627void btrfs_sysfs_remove_device(struct btrfs_device *device)
1628{
1629 struct kobject *devices_kobj;
1630
1631 /*
1632 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1633 * fs_info::fs_devices.
1634 */
1635 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1636 ASSERT(devices_kobj);
1637
1638 if (device->bdev)
1639 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1640
1641 if (device->devid_kobj.state_initialized) {
1642 kobject_del(&device->devid_kobj);
1643 kobject_put(&device->devid_kobj);
1644 wait_for_completion(&device->kobj_unregister);
1645 }
1646}
1647
1648static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1649 struct kobj_attribute *a,
1650 char *buf)
1651{
1652 int val;
1653 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1654 devid_kobj);
1655
1656 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1657
1658 return sysfs_emit(buf, "%d\n", val);
1659}
1660BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1661
1662static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1663 struct kobj_attribute *a, char *buf)
1664{
1665 int val;
1666 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1667 devid_kobj);
1668
1669 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1670
1671 return sysfs_emit(buf, "%d\n", val);
1672}
1673BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1674
1675static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1676 struct kobj_attribute *a,
1677 char *buf)
1678{
1679 int val;
1680 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1681 devid_kobj);
1682
1683 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1684
1685 return sysfs_emit(buf, "%d\n", val);
1686}
1687BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1688
1689static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
1690 struct kobj_attribute *a,
1691 char *buf)
1692{
1693 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1694 devid_kobj);
1695
1696 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max));
1697}
1698
1699static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
1700 struct kobj_attribute *a,
1701 const char *buf, size_t len)
1702{
1703 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1704 devid_kobj);
1705 char *endptr;
1706 unsigned long long limit;
1707
1708 limit = memparse(buf, &endptr);
1709 WRITE_ONCE(device->scrub_speed_max, limit);
1710 return len;
1711}
1712BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show,
1713 btrfs_devinfo_scrub_speed_max_store);
1714
1715static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1716 struct kobj_attribute *a, char *buf)
1717{
1718 int val;
1719 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1720 devid_kobj);
1721
1722 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1723
1724 return sysfs_emit(buf, "%d\n", val);
1725}
1726BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1727
1728static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj,
1729 struct kobj_attribute *a, char *buf)
1730{
1731 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1732 devid_kobj);
1733
1734 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid);
1735}
1736BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show);
1737
1738static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
1739 struct kobj_attribute *a, char *buf)
1740{
1741 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1742 devid_kobj);
1743
1744 if (!device->dev_stats_valid)
1745 return sysfs_emit(buf, "invalid\n");
1746
1747 /*
1748 * Print all at once so we get a snapshot of all values from the same
1749 * time. Keep them in sync and in order of definition of
1750 * btrfs_dev_stat_values.
1751 */
1752 return sysfs_emit(buf,
1753 "write_errs %d\n"
1754 "read_errs %d\n"
1755 "flush_errs %d\n"
1756 "corruption_errs %d\n"
1757 "generation_errs %d\n",
1758 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS),
1759 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS),
1760 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS),
1761 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS),
1762 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS));
1763}
1764BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show);
1765
1766/*
1767 * Information about one device.
1768 *
1769 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/
1770 */
1771static struct attribute *devid_attrs[] = {
1772 BTRFS_ATTR_PTR(devid, error_stats),
1773 BTRFS_ATTR_PTR(devid, fsid),
1774 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1775 BTRFS_ATTR_PTR(devid, missing),
1776 BTRFS_ATTR_PTR(devid, replace_target),
1777 BTRFS_ATTR_PTR(devid, scrub_speed_max),
1778 BTRFS_ATTR_PTR(devid, writeable),
1779 NULL
1780};
1781ATTRIBUTE_GROUPS(devid);
1782
1783static void btrfs_release_devid_kobj(struct kobject *kobj)
1784{
1785 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1786 devid_kobj);
1787
1788 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1789 complete(&device->kobj_unregister);
1790}
1791
1792static struct kobj_type devid_ktype = {
1793 .sysfs_ops = &kobj_sysfs_ops,
1794 .default_groups = devid_groups,
1795 .release = btrfs_release_devid_kobj,
1796};
1797
1798int btrfs_sysfs_add_device(struct btrfs_device *device)
1799{
1800 int ret;
1801 unsigned int nofs_flag;
1802 struct kobject *devices_kobj;
1803 struct kobject *devinfo_kobj;
1804
1805 /*
1806 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
1807 * for the seed fs_devices
1808 */
1809 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1810 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
1811 ASSERT(devices_kobj);
1812 ASSERT(devinfo_kobj);
1813
1814 nofs_flag = memalloc_nofs_save();
1815
1816 if (device->bdev) {
1817 struct kobject *disk_kobj = bdev_kobj(device->bdev);
1818
1819 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
1820 if (ret) {
1821 btrfs_warn(device->fs_info,
1822 "creating sysfs device link for devid %llu failed: %d",
1823 device->devid, ret);
1824 goto out;
1825 }
1826 }
1827
1828 init_completion(&device->kobj_unregister);
1829 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
1830 devinfo_kobj, "%llu", device->devid);
1831 if (ret) {
1832 kobject_put(&device->devid_kobj);
1833 btrfs_warn(device->fs_info,
1834 "devinfo init for devid %llu failed: %d",
1835 device->devid, ret);
1836 }
1837
1838out:
1839 memalloc_nofs_restore(nofs_flag);
1840 return ret;
1841}
1842
1843static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
1844{
1845 int ret;
1846 struct btrfs_device *device;
1847 struct btrfs_fs_devices *seed;
1848
1849 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1850 ret = btrfs_sysfs_add_device(device);
1851 if (ret)
1852 goto fail;
1853 }
1854
1855 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1856 list_for_each_entry(device, &seed->devices, dev_list) {
1857 ret = btrfs_sysfs_add_device(device);
1858 if (ret)
1859 goto fail;
1860 }
1861 }
1862
1863 return 0;
1864
1865fail:
1866 btrfs_sysfs_remove_fs_devices(fs_devices);
1867 return ret;
1868}
1869
1870void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1871{
1872 int ret;
1873
1874 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1875 if (ret)
1876 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1877 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1878 &disk_to_dev(bdev->bd_disk)->kobj);
1879}
1880
1881void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
1882
1883{
1884 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1885
1886 /*
1887 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1888 * directory
1889 */
1890 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
1891 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1892 btrfs_warn(fs_devices->fs_info,
1893 "sysfs: failed to create fsid for sprout");
1894}
1895
1896void btrfs_sysfs_update_devid(struct btrfs_device *device)
1897{
1898 char tmp[24];
1899
1900 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
1901
1902 if (kobject_rename(&device->devid_kobj, tmp))
1903 btrfs_warn(device->fs_devices->fs_info,
1904 "sysfs: failed to update devid for %llu",
1905 device->devid);
1906}
1907
1908/* /sys/fs/btrfs/ entry */
1909static struct kset *btrfs_kset;
1910
1911/*
1912 * Creates:
1913 * /sys/fs/btrfs/UUID
1914 *
1915 * Can be called by the device discovery thread.
1916 */
1917int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
1918{
1919 int error;
1920
1921 init_completion(&fs_devs->kobj_unregister);
1922 fs_devs->fsid_kobj.kset = btrfs_kset;
1923 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
1924 "%pU", fs_devs->fsid);
1925 if (error) {
1926 kobject_put(&fs_devs->fsid_kobj);
1927 return error;
1928 }
1929
1930 fs_devs->devices_kobj = kobject_create_and_add("devices",
1931 &fs_devs->fsid_kobj);
1932 if (!fs_devs->devices_kobj) {
1933 btrfs_err(fs_devs->fs_info,
1934 "failed to init sysfs device interface");
1935 btrfs_sysfs_remove_fsid(fs_devs);
1936 return -ENOMEM;
1937 }
1938
1939 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
1940 &fs_devs->fsid_kobj);
1941 if (!fs_devs->devinfo_kobj) {
1942 btrfs_err(fs_devs->fs_info,
1943 "failed to init sysfs devinfo kobject");
1944 btrfs_sysfs_remove_fsid(fs_devs);
1945 return -ENOMEM;
1946 }
1947
1948 return 0;
1949}
1950
1951int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1952{
1953 int error;
1954 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1955 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1956
1957 error = btrfs_sysfs_add_fs_devices(fs_devs);
1958 if (error)
1959 return error;
1960
1961 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1962 if (error) {
1963 btrfs_sysfs_remove_fs_devices(fs_devs);
1964 return error;
1965 }
1966
1967 error = sysfs_create_group(fsid_kobj,
1968 &btrfs_feature_attr_group);
1969 if (error)
1970 goto failure;
1971
1972#ifdef CONFIG_BTRFS_DEBUG
1973 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
1974 if (!fs_info->debug_kobj) {
1975 error = -ENOMEM;
1976 goto failure;
1977 }
1978
1979 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1980 if (error)
1981 goto failure;
1982#endif
1983
1984 /* Discard directory */
1985 fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj);
1986 if (!fs_info->discard_kobj) {
1987 error = -ENOMEM;
1988 goto failure;
1989 }
1990
1991 error = sysfs_create_files(fs_info->discard_kobj, discard_attrs);
1992 if (error)
1993 goto failure;
1994
1995 error = addrm_unknown_feature_attrs(fs_info, true);
1996 if (error)
1997 goto failure;
1998
1999 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
2000 if (error)
2001 goto failure;
2002
2003 fs_info->space_info_kobj = kobject_create_and_add("allocation",
2004 fsid_kobj);
2005 if (!fs_info->space_info_kobj) {
2006 error = -ENOMEM;
2007 goto failure;
2008 }
2009
2010 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
2011 if (error)
2012 goto failure;
2013
2014 return 0;
2015failure:
2016 btrfs_sysfs_remove_mounted(fs_info);
2017 return error;
2018}
2019
2020static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj,
2021 struct kobj_attribute *a,
2022 char *buf)
2023{
2024 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2025 bool enabled;
2026
2027 spin_lock(&fs_info->qgroup_lock);
2028 enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON;
2029 spin_unlock(&fs_info->qgroup_lock);
2030
2031 return sysfs_emit(buf, "%d\n", enabled);
2032}
2033BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show);
2034
2035static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj,
2036 struct kobj_attribute *a,
2037 char *buf)
2038{
2039 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2040 bool inconsistent;
2041
2042 spin_lock(&fs_info->qgroup_lock);
2043 inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT);
2044 spin_unlock(&fs_info->qgroup_lock);
2045
2046 return sysfs_emit(buf, "%d\n", inconsistent);
2047}
2048BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show);
2049
2050static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj,
2051 struct kobj_attribute *a,
2052 char *buf)
2053{
2054 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2055 u8 result;
2056
2057 spin_lock(&fs_info->qgroup_lock);
2058 result = fs_info->qgroup_drop_subtree_thres;
2059 spin_unlock(&fs_info->qgroup_lock);
2060
2061 return sysfs_emit(buf, "%d\n", result);
2062}
2063
2064static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj,
2065 struct kobj_attribute *a,
2066 const char *buf, size_t len)
2067{
2068 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2069 u8 new_thres;
2070 int ret;
2071
2072 ret = kstrtou8(buf, 10, &new_thres);
2073 if (ret)
2074 return -EINVAL;
2075
2076 if (new_thres > BTRFS_MAX_LEVEL)
2077 return -EINVAL;
2078
2079 spin_lock(&fs_info->qgroup_lock);
2080 fs_info->qgroup_drop_subtree_thres = new_thres;
2081 spin_unlock(&fs_info->qgroup_lock);
2082
2083 return len;
2084}
2085BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show,
2086 qgroup_drop_subtree_thres_store);
2087
2088/*
2089 * Qgroups global info
2090 *
2091 * Path: /sys/fs/btrfs/<uuid>/qgroups/
2092 */
2093static struct attribute *qgroups_attrs[] = {
2094 BTRFS_ATTR_PTR(qgroups, enabled),
2095 BTRFS_ATTR_PTR(qgroups, inconsistent),
2096 BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold),
2097 NULL
2098};
2099ATTRIBUTE_GROUPS(qgroups);
2100
2101static void qgroups_release(struct kobject *kobj)
2102{
2103 kfree(kobj);
2104}
2105
2106static struct kobj_type qgroups_ktype = {
2107 .sysfs_ops = &kobj_sysfs_ops,
2108 .default_groups = qgroups_groups,
2109 .release = qgroups_release,
2110};
2111
2112static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
2113{
2114 return to_fs_info(kobj->parent->parent);
2115}
2116
2117#define QGROUP_ATTR(_member, _show_name) \
2118static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
2119 struct kobj_attribute *a, \
2120 char *buf) \
2121{ \
2122 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2123 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2124 struct btrfs_qgroup, kobj); \
2125 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
2126} \
2127BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
2128
2129#define QGROUP_RSV_ATTR(_name, _type) \
2130static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
2131 struct kobj_attribute *a, \
2132 char *buf) \
2133{ \
2134 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2135 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2136 struct btrfs_qgroup, kobj); \
2137 return btrfs_show_u64(&qgroup->rsv.values[_type], \
2138 &fs_info->qgroup_lock, buf); \
2139} \
2140BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
2141
2142QGROUP_ATTR(rfer, referenced);
2143QGROUP_ATTR(excl, exclusive);
2144QGROUP_ATTR(max_rfer, max_referenced);
2145QGROUP_ATTR(max_excl, max_exclusive);
2146QGROUP_ATTR(lim_flags, limit_flags);
2147QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
2148QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
2149QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
2150
2151/*
2152 * Qgroup information.
2153 *
2154 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/
2155 */
2156static struct attribute *qgroup_attrs[] = {
2157 BTRFS_ATTR_PTR(qgroup, referenced),
2158 BTRFS_ATTR_PTR(qgroup, exclusive),
2159 BTRFS_ATTR_PTR(qgroup, max_referenced),
2160 BTRFS_ATTR_PTR(qgroup, max_exclusive),
2161 BTRFS_ATTR_PTR(qgroup, limit_flags),
2162 BTRFS_ATTR_PTR(qgroup, rsv_data),
2163 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
2164 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
2165 NULL
2166};
2167ATTRIBUTE_GROUPS(qgroup);
2168
2169static void qgroup_release(struct kobject *kobj)
2170{
2171 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
2172
2173 memset(&qgroup->kobj, 0, sizeof(*kobj));
2174}
2175
2176static struct kobj_type qgroup_ktype = {
2177 .sysfs_ops = &kobj_sysfs_ops,
2178 .release = qgroup_release,
2179 .default_groups = qgroup_groups,
2180};
2181
2182int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
2183 struct btrfs_qgroup *qgroup)
2184{
2185 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
2186 int ret;
2187
2188 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2189 return 0;
2190 if (qgroup->kobj.state_initialized)
2191 return 0;
2192 if (!qgroups_kobj)
2193 return -EINVAL;
2194
2195 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
2196 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
2197 btrfs_qgroup_subvolid(qgroup->qgroupid));
2198 if (ret < 0)
2199 kobject_put(&qgroup->kobj);
2200
2201 return ret;
2202}
2203
2204void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
2205{
2206 struct btrfs_qgroup *qgroup;
2207 struct btrfs_qgroup *next;
2208
2209 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2210 return;
2211
2212 rbtree_postorder_for_each_entry_safe(qgroup, next,
2213 &fs_info->qgroup_tree, node)
2214 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
2215 if (fs_info->qgroups_kobj) {
2216 kobject_del(fs_info->qgroups_kobj);
2217 kobject_put(fs_info->qgroups_kobj);
2218 fs_info->qgroups_kobj = NULL;
2219 }
2220}
2221
2222/* Called when qgroups get initialized, thus there is no need for locking */
2223int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
2224{
2225 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2226 struct btrfs_qgroup *qgroup;
2227 struct btrfs_qgroup *next;
2228 int ret = 0;
2229
2230 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2231 return 0;
2232
2233 ASSERT(fsid_kobj);
2234 if (fs_info->qgroups_kobj)
2235 return 0;
2236
2237 fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
2238 if (!fs_info->qgroups_kobj)
2239 return -ENOMEM;
2240
2241 ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype,
2242 fsid_kobj, "qgroups");
2243 if (ret < 0)
2244 goto out;
2245
2246 rbtree_postorder_for_each_entry_safe(qgroup, next,
2247 &fs_info->qgroup_tree, node) {
2248 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
2249 if (ret < 0)
2250 goto out;
2251 }
2252
2253out:
2254 if (ret < 0)
2255 btrfs_sysfs_del_qgroups(fs_info);
2256 return ret;
2257}
2258
2259void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
2260 struct btrfs_qgroup *qgroup)
2261{
2262 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2263 return;
2264
2265 if (qgroup->kobj.state_initialized) {
2266 kobject_del(&qgroup->kobj);
2267 kobject_put(&qgroup->kobj);
2268 }
2269}
2270
2271/*
2272 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
2273 * values in superblock. Call after any changes to incompat/compat_ro flags
2274 */
2275void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
2276 u64 bit, enum btrfs_feature_set set)
2277{
2278 struct btrfs_fs_devices *fs_devs;
2279 struct kobject *fsid_kobj;
2280 u64 __maybe_unused features;
2281 int __maybe_unused ret;
2282
2283 if (!fs_info)
2284 return;
2285
2286 /*
2287 * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not
2288 * safe when called from some contexts (eg. balance)
2289 */
2290 features = get_features(fs_info, set);
2291 ASSERT(bit & supported_feature_masks[set]);
2292
2293 fs_devs = fs_info->fs_devices;
2294 fsid_kobj = &fs_devs->fsid_kobj;
2295
2296 if (!fsid_kobj->state_initialized)
2297 return;
2298
2299 /*
2300 * FIXME: this is too heavy to update just one value, ideally we'd like
2301 * to use sysfs_update_group but some refactoring is needed first.
2302 */
2303 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
2304 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
2305}
2306
2307int __init btrfs_init_sysfs(void)
2308{
2309 int ret;
2310
2311 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
2312 if (!btrfs_kset)
2313 return -ENOMEM;
2314
2315 init_feature_attrs();
2316 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2317 if (ret)
2318 goto out2;
2319 ret = sysfs_merge_group(&btrfs_kset->kobj,
2320 &btrfs_static_feature_attr_group);
2321 if (ret)
2322 goto out_remove_group;
2323
2324#ifdef CONFIG_BTRFS_DEBUG
2325 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2326 if (ret) {
2327 sysfs_unmerge_group(&btrfs_kset->kobj,
2328 &btrfs_static_feature_attr_group);
2329 goto out_remove_group;
2330 }
2331#endif
2332
2333 return 0;
2334
2335out_remove_group:
2336 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2337out2:
2338 kset_unregister(btrfs_kset);
2339
2340 return ret;
2341}
2342
2343void __cold btrfs_exit_sysfs(void)
2344{
2345 sysfs_unmerge_group(&btrfs_kset->kobj,
2346 &btrfs_static_feature_attr_group);
2347 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2348#ifdef CONFIG_BTRFS_DEBUG
2349 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2350#endif
2351 kset_unregister(btrfs_kset);
2352}