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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#include <linux/sched.h>
7#include <linux/sched/mm.h>
8#include <linux/slab.h>
9#include <linux/spinlock.h>
10#include <linux/completion.h>
11#include <linux/bug.h>
12
13#include "ctree.h"
14#include "disk-io.h"
15#include "transaction.h"
16#include "sysfs.h"
17#include "volumes.h"
18#include "space-info.h"
19#include "block-group.h"
20
21struct btrfs_feature_attr {
22 struct kobj_attribute kobj_attr;
23 enum btrfs_feature_set feature_set;
24 u64 feature_bit;
25};
26
27/* For raid type sysfs entries */
28struct raid_kobject {
29 u64 flags;
30 struct kobject kobj;
31};
32
33#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
34{ \
35 .attr = { .name = __stringify(_name), .mode = _mode }, \
36 .show = _show, \
37 .store = _store, \
38}
39
40#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
41 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
42 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
43
44#define BTRFS_ATTR(_prefix, _name, _show) \
45 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
46 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
47
48#define BTRFS_ATTR_PTR(_prefix, _name) \
49 (&btrfs_attr_##_prefix##_##_name.attr)
50
51#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
52static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
53 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
54 btrfs_feature_attr_show, \
55 btrfs_feature_attr_store), \
56 .feature_set = _feature_set, \
57 .feature_bit = _feature_prefix ##_## _feature_bit, \
58}
59#define BTRFS_FEAT_ATTR_PTR(_name) \
60 (&btrfs_attr_features_##_name.kobj_attr.attr)
61
62#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
63 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
64#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
65 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
66#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
67 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
68
69static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
70static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
71
72static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
73{
74 return container_of(a, struct btrfs_feature_attr, kobj_attr);
75}
76
77static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
78{
79 return container_of(attr, struct kobj_attribute, attr);
80}
81
82static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
83 struct attribute *attr)
84{
85 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
86}
87
88static u64 get_features(struct btrfs_fs_info *fs_info,
89 enum btrfs_feature_set set)
90{
91 struct btrfs_super_block *disk_super = fs_info->super_copy;
92 if (set == FEAT_COMPAT)
93 return btrfs_super_compat_flags(disk_super);
94 else if (set == FEAT_COMPAT_RO)
95 return btrfs_super_compat_ro_flags(disk_super);
96 else
97 return btrfs_super_incompat_flags(disk_super);
98}
99
100static void set_features(struct btrfs_fs_info *fs_info,
101 enum btrfs_feature_set set, u64 features)
102{
103 struct btrfs_super_block *disk_super = fs_info->super_copy;
104 if (set == FEAT_COMPAT)
105 btrfs_set_super_compat_flags(disk_super, features);
106 else if (set == FEAT_COMPAT_RO)
107 btrfs_set_super_compat_ro_flags(disk_super, features);
108 else
109 btrfs_set_super_incompat_flags(disk_super, features);
110}
111
112static int can_modify_feature(struct btrfs_feature_attr *fa)
113{
114 int val = 0;
115 u64 set, clear;
116 switch (fa->feature_set) {
117 case FEAT_COMPAT:
118 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
119 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
120 break;
121 case FEAT_COMPAT_RO:
122 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
123 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
124 break;
125 case FEAT_INCOMPAT:
126 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
127 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
128 break;
129 default:
130 pr_warn("btrfs: sysfs: unknown feature set %d\n",
131 fa->feature_set);
132 return 0;
133 }
134
135 if (set & fa->feature_bit)
136 val |= 1;
137 if (clear & fa->feature_bit)
138 val |= 2;
139
140 return val;
141}
142
143static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
144 struct kobj_attribute *a, char *buf)
145{
146 int val = 0;
147 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
148 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
149 if (fs_info) {
150 u64 features = get_features(fs_info, fa->feature_set);
151 if (features & fa->feature_bit)
152 val = 1;
153 } else
154 val = can_modify_feature(fa);
155
156 return snprintf(buf, PAGE_SIZE, "%d\n", val);
157}
158
159static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
160 struct kobj_attribute *a,
161 const char *buf, size_t count)
162{
163 struct btrfs_fs_info *fs_info;
164 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
165 u64 features, set, clear;
166 unsigned long val;
167 int ret;
168
169 fs_info = to_fs_info(kobj);
170 if (!fs_info)
171 return -EPERM;
172
173 if (sb_rdonly(fs_info->sb))
174 return -EROFS;
175
176 ret = kstrtoul(skip_spaces(buf), 0, &val);
177 if (ret)
178 return ret;
179
180 if (fa->feature_set == FEAT_COMPAT) {
181 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
182 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
183 } else if (fa->feature_set == FEAT_COMPAT_RO) {
184 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
185 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
186 } else {
187 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
188 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
189 }
190
191 features = get_features(fs_info, fa->feature_set);
192
193 /* Nothing to do */
194 if ((val && (features & fa->feature_bit)) ||
195 (!val && !(features & fa->feature_bit)))
196 return count;
197
198 if ((val && !(set & fa->feature_bit)) ||
199 (!val && !(clear & fa->feature_bit))) {
200 btrfs_info(fs_info,
201 "%sabling feature %s on mounted fs is not supported.",
202 val ? "En" : "Dis", fa->kobj_attr.attr.name);
203 return -EPERM;
204 }
205
206 btrfs_info(fs_info, "%s %s feature flag",
207 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
208
209 spin_lock(&fs_info->super_lock);
210 features = get_features(fs_info, fa->feature_set);
211 if (val)
212 features |= fa->feature_bit;
213 else
214 features &= ~fa->feature_bit;
215 set_features(fs_info, fa->feature_set, features);
216 spin_unlock(&fs_info->super_lock);
217
218 /*
219 * We don't want to do full transaction commit from inside sysfs
220 */
221 btrfs_set_pending(fs_info, COMMIT);
222 wake_up_process(fs_info->transaction_kthread);
223
224 return count;
225}
226
227static umode_t btrfs_feature_visible(struct kobject *kobj,
228 struct attribute *attr, int unused)
229{
230 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
231 umode_t mode = attr->mode;
232
233 if (fs_info) {
234 struct btrfs_feature_attr *fa;
235 u64 features;
236
237 fa = attr_to_btrfs_feature_attr(attr);
238 features = get_features(fs_info, fa->feature_set);
239
240 if (can_modify_feature(fa))
241 mode |= S_IWUSR;
242 else if (!(features & fa->feature_bit))
243 mode = 0;
244 }
245
246 return mode;
247}
248
249BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
250BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
251BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
252BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
253BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
254BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
255BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
256BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
257BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
258BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
259BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
260BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
261
262static struct attribute *btrfs_supported_feature_attrs[] = {
263 BTRFS_FEAT_ATTR_PTR(mixed_backref),
264 BTRFS_FEAT_ATTR_PTR(default_subvol),
265 BTRFS_FEAT_ATTR_PTR(mixed_groups),
266 BTRFS_FEAT_ATTR_PTR(compress_lzo),
267 BTRFS_FEAT_ATTR_PTR(compress_zstd),
268 BTRFS_FEAT_ATTR_PTR(big_metadata),
269 BTRFS_FEAT_ATTR_PTR(extended_iref),
270 BTRFS_FEAT_ATTR_PTR(raid56),
271 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
272 BTRFS_FEAT_ATTR_PTR(no_holes),
273 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
274 BTRFS_FEAT_ATTR_PTR(free_space_tree),
275 NULL
276};
277
278/*
279 * Features which depend on feature bits and may differ between each fs.
280 *
281 * /sys/fs/btrfs/features lists all available features of this kernel while
282 * /sys/fs/btrfs/UUID/features shows features of the fs which are enabled or
283 * can be changed online.
284 */
285static const struct attribute_group btrfs_feature_attr_group = {
286 .name = "features",
287 .is_visible = btrfs_feature_visible,
288 .attrs = btrfs_supported_feature_attrs,
289};
290
291static ssize_t rmdir_subvol_show(struct kobject *kobj,
292 struct kobj_attribute *ka, char *buf)
293{
294 return snprintf(buf, PAGE_SIZE, "0\n");
295}
296BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
297
298static struct attribute *btrfs_supported_static_feature_attrs[] = {
299 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
300 NULL
301};
302
303/*
304 * Features which only depend on kernel version.
305 *
306 * These are listed in /sys/fs/btrfs/features along with
307 * btrfs_feature_attr_group
308 */
309static const struct attribute_group btrfs_static_feature_attr_group = {
310 .name = "features",
311 .attrs = btrfs_supported_static_feature_attrs,
312};
313
314#ifdef CONFIG_BTRFS_DEBUG
315
316/*
317 * Runtime debugging exported via sysfs
318 *
319 * /sys/fs/btrfs/debug - applies to module or all filesystems
320 * /sys/fs/btrfs/UUID - applies only to the given filesystem
321 */
322static struct attribute *btrfs_debug_feature_attrs[] = {
323 NULL
324};
325
326static const struct attribute_group btrfs_debug_feature_attr_group = {
327 .name = "debug",
328 .attrs = btrfs_debug_feature_attrs,
329};
330
331#endif
332
333static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
334{
335 u64 val;
336 if (lock)
337 spin_lock(lock);
338 val = *value_ptr;
339 if (lock)
340 spin_unlock(lock);
341 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
342}
343
344static ssize_t global_rsv_size_show(struct kobject *kobj,
345 struct kobj_attribute *ka, char *buf)
346{
347 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
348 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
349 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
350}
351BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
352
353static ssize_t global_rsv_reserved_show(struct kobject *kobj,
354 struct kobj_attribute *a, char *buf)
355{
356 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
357 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
358 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
359}
360BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
361
362#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
363#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
364
365static ssize_t raid_bytes_show(struct kobject *kobj,
366 struct kobj_attribute *attr, char *buf);
367BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
368BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
369
370static ssize_t raid_bytes_show(struct kobject *kobj,
371 struct kobj_attribute *attr, char *buf)
372
373{
374 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
375 struct btrfs_block_group_cache *block_group;
376 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
377 u64 val = 0;
378
379 down_read(&sinfo->groups_sem);
380 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
381 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
382 val += block_group->key.offset;
383 else
384 val += btrfs_block_group_used(&block_group->item);
385 }
386 up_read(&sinfo->groups_sem);
387 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
388}
389
390static struct attribute *raid_attrs[] = {
391 BTRFS_ATTR_PTR(raid, total_bytes),
392 BTRFS_ATTR_PTR(raid, used_bytes),
393 NULL
394};
395ATTRIBUTE_GROUPS(raid);
396
397static void release_raid_kobj(struct kobject *kobj)
398{
399 kfree(to_raid_kobj(kobj));
400}
401
402static struct kobj_type btrfs_raid_ktype = {
403 .sysfs_ops = &kobj_sysfs_ops,
404 .release = release_raid_kobj,
405 .default_groups = raid_groups,
406};
407
408#define SPACE_INFO_ATTR(field) \
409static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
410 struct kobj_attribute *a, \
411 char *buf) \
412{ \
413 struct btrfs_space_info *sinfo = to_space_info(kobj); \
414 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
415} \
416BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
417
418static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
419 struct kobj_attribute *a,
420 char *buf)
421{
422 struct btrfs_space_info *sinfo = to_space_info(kobj);
423 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
424 return snprintf(buf, PAGE_SIZE, "%lld\n", val);
425}
426
427SPACE_INFO_ATTR(flags);
428SPACE_INFO_ATTR(total_bytes);
429SPACE_INFO_ATTR(bytes_used);
430SPACE_INFO_ATTR(bytes_pinned);
431SPACE_INFO_ATTR(bytes_reserved);
432SPACE_INFO_ATTR(bytes_may_use);
433SPACE_INFO_ATTR(bytes_readonly);
434SPACE_INFO_ATTR(disk_used);
435SPACE_INFO_ATTR(disk_total);
436BTRFS_ATTR(space_info, total_bytes_pinned,
437 btrfs_space_info_show_total_bytes_pinned);
438
439static struct attribute *space_info_attrs[] = {
440 BTRFS_ATTR_PTR(space_info, flags),
441 BTRFS_ATTR_PTR(space_info, total_bytes),
442 BTRFS_ATTR_PTR(space_info, bytes_used),
443 BTRFS_ATTR_PTR(space_info, bytes_pinned),
444 BTRFS_ATTR_PTR(space_info, bytes_reserved),
445 BTRFS_ATTR_PTR(space_info, bytes_may_use),
446 BTRFS_ATTR_PTR(space_info, bytes_readonly),
447 BTRFS_ATTR_PTR(space_info, disk_used),
448 BTRFS_ATTR_PTR(space_info, disk_total),
449 BTRFS_ATTR_PTR(space_info, total_bytes_pinned),
450 NULL,
451};
452ATTRIBUTE_GROUPS(space_info);
453
454static void space_info_release(struct kobject *kobj)
455{
456 struct btrfs_space_info *sinfo = to_space_info(kobj);
457 percpu_counter_destroy(&sinfo->total_bytes_pinned);
458 kfree(sinfo);
459}
460
461static struct kobj_type space_info_ktype = {
462 .sysfs_ops = &kobj_sysfs_ops,
463 .release = space_info_release,
464 .default_groups = space_info_groups,
465};
466
467static const struct attribute *allocation_attrs[] = {
468 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
469 BTRFS_ATTR_PTR(allocation, global_rsv_size),
470 NULL,
471};
472
473static ssize_t btrfs_label_show(struct kobject *kobj,
474 struct kobj_attribute *a, char *buf)
475{
476 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
477 char *label = fs_info->super_copy->label;
478 ssize_t ret;
479
480 spin_lock(&fs_info->super_lock);
481 ret = snprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
482 spin_unlock(&fs_info->super_lock);
483
484 return ret;
485}
486
487static ssize_t btrfs_label_store(struct kobject *kobj,
488 struct kobj_attribute *a,
489 const char *buf, size_t len)
490{
491 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
492 size_t p_len;
493
494 if (!fs_info)
495 return -EPERM;
496
497 if (sb_rdonly(fs_info->sb))
498 return -EROFS;
499
500 /*
501 * p_len is the len until the first occurrence of either
502 * '\n' or '\0'
503 */
504 p_len = strcspn(buf, "\n");
505
506 if (p_len >= BTRFS_LABEL_SIZE)
507 return -EINVAL;
508
509 spin_lock(&fs_info->super_lock);
510 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
511 memcpy(fs_info->super_copy->label, buf, p_len);
512 spin_unlock(&fs_info->super_lock);
513
514 /*
515 * We don't want to do full transaction commit from inside sysfs
516 */
517 btrfs_set_pending(fs_info, COMMIT);
518 wake_up_process(fs_info->transaction_kthread);
519
520 return len;
521}
522BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
523
524static ssize_t btrfs_nodesize_show(struct kobject *kobj,
525 struct kobj_attribute *a, char *buf)
526{
527 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
528
529 return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
530}
531
532BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
533
534static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
535 struct kobj_attribute *a, char *buf)
536{
537 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
538
539 return snprintf(buf, PAGE_SIZE, "%u\n",
540 fs_info->super_copy->sectorsize);
541}
542
543BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
544
545static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
546 struct kobj_attribute *a, char *buf)
547{
548 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
549
550 return snprintf(buf, PAGE_SIZE, "%u\n",
551 fs_info->super_copy->sectorsize);
552}
553
554BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
555
556static ssize_t quota_override_show(struct kobject *kobj,
557 struct kobj_attribute *a, char *buf)
558{
559 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
560 int quota_override;
561
562 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
563 return snprintf(buf, PAGE_SIZE, "%d\n", quota_override);
564}
565
566static ssize_t quota_override_store(struct kobject *kobj,
567 struct kobj_attribute *a,
568 const char *buf, size_t len)
569{
570 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
571 unsigned long knob;
572 int err;
573
574 if (!fs_info)
575 return -EPERM;
576
577 if (!capable(CAP_SYS_RESOURCE))
578 return -EPERM;
579
580 err = kstrtoul(buf, 10, &knob);
581 if (err)
582 return err;
583 if (knob > 1)
584 return -EINVAL;
585
586 if (knob)
587 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
588 else
589 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
590
591 return len;
592}
593
594BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
595
596static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
597 struct kobj_attribute *a, char *buf)
598{
599 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
600
601 return snprintf(buf, PAGE_SIZE, "%pU\n",
602 fs_info->fs_devices->metadata_uuid);
603}
604
605BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
606
607static const struct attribute *btrfs_attrs[] = {
608 BTRFS_ATTR_PTR(, label),
609 BTRFS_ATTR_PTR(, nodesize),
610 BTRFS_ATTR_PTR(, sectorsize),
611 BTRFS_ATTR_PTR(, clone_alignment),
612 BTRFS_ATTR_PTR(, quota_override),
613 BTRFS_ATTR_PTR(, metadata_uuid),
614 NULL,
615};
616
617static void btrfs_release_fsid_kobj(struct kobject *kobj)
618{
619 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
620
621 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
622 complete(&fs_devs->kobj_unregister);
623}
624
625static struct kobj_type btrfs_ktype = {
626 .sysfs_ops = &kobj_sysfs_ops,
627 .release = btrfs_release_fsid_kobj,
628};
629
630static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
631{
632 if (kobj->ktype != &btrfs_ktype)
633 return NULL;
634 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
635}
636
637static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
638{
639 if (kobj->ktype != &btrfs_ktype)
640 return NULL;
641 return to_fs_devs(kobj)->fs_info;
642}
643
644#define NUM_FEATURE_BITS 64
645#define BTRFS_FEATURE_NAME_MAX 13
646static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
647static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
648
649static const u64 supported_feature_masks[FEAT_MAX] = {
650 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
651 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
652 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
653};
654
655static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
656{
657 int set;
658
659 for (set = 0; set < FEAT_MAX; set++) {
660 int i;
661 struct attribute *attrs[2];
662 struct attribute_group agroup = {
663 .name = "features",
664 .attrs = attrs,
665 };
666 u64 features = get_features(fs_info, set);
667 features &= ~supported_feature_masks[set];
668
669 if (!features)
670 continue;
671
672 attrs[1] = NULL;
673 for (i = 0; i < NUM_FEATURE_BITS; i++) {
674 struct btrfs_feature_attr *fa;
675
676 if (!(features & (1ULL << i)))
677 continue;
678
679 fa = &btrfs_feature_attrs[set][i];
680 attrs[0] = &fa->kobj_attr.attr;
681 if (add) {
682 int ret;
683 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
684 &agroup);
685 if (ret)
686 return ret;
687 } else
688 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
689 &agroup);
690 }
691
692 }
693 return 0;
694}
695
696static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
697{
698 if (fs_devs->device_dir_kobj) {
699 kobject_del(fs_devs->device_dir_kobj);
700 kobject_put(fs_devs->device_dir_kobj);
701 fs_devs->device_dir_kobj = NULL;
702 }
703
704 if (fs_devs->fsid_kobj.state_initialized) {
705 kobject_del(&fs_devs->fsid_kobj);
706 kobject_put(&fs_devs->fsid_kobj);
707 wait_for_completion(&fs_devs->kobj_unregister);
708 }
709}
710
711/* when fs_devs is NULL it will remove all fsid kobject */
712void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
713{
714 struct list_head *fs_uuids = btrfs_get_fs_uuids();
715
716 if (fs_devs) {
717 __btrfs_sysfs_remove_fsid(fs_devs);
718 return;
719 }
720
721 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
722 __btrfs_sysfs_remove_fsid(fs_devs);
723 }
724}
725
726void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
727{
728 btrfs_reset_fs_info_ptr(fs_info);
729
730 if (fs_info->space_info_kobj) {
731 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
732 kobject_del(fs_info->space_info_kobj);
733 kobject_put(fs_info->space_info_kobj);
734 }
735 addrm_unknown_feature_attrs(fs_info, false);
736 sysfs_remove_group(&fs_info->fs_devices->fsid_kobj, &btrfs_feature_attr_group);
737 sysfs_remove_files(&fs_info->fs_devices->fsid_kobj, btrfs_attrs);
738 btrfs_sysfs_rm_device_link(fs_info->fs_devices, NULL);
739}
740
741static const char * const btrfs_feature_set_names[FEAT_MAX] = {
742 [FEAT_COMPAT] = "compat",
743 [FEAT_COMPAT_RO] = "compat_ro",
744 [FEAT_INCOMPAT] = "incompat",
745};
746
747const char * const btrfs_feature_set_name(enum btrfs_feature_set set)
748{
749 return btrfs_feature_set_names[set];
750}
751
752char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
753{
754 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
755 int len = 0;
756 int i;
757 char *str;
758
759 str = kmalloc(bufsize, GFP_KERNEL);
760 if (!str)
761 return str;
762
763 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
764 const char *name;
765
766 if (!(flags & (1ULL << i)))
767 continue;
768
769 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
770 len += snprintf(str + len, bufsize - len, "%s%s",
771 len ? "," : "", name);
772 }
773
774 return str;
775}
776
777static void init_feature_attrs(void)
778{
779 struct btrfs_feature_attr *fa;
780 int set, i;
781
782 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
783 ARRAY_SIZE(btrfs_feature_attrs));
784 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
785 ARRAY_SIZE(btrfs_feature_attrs[0]));
786
787 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
788 memset(btrfs_unknown_feature_names, 0,
789 sizeof(btrfs_unknown_feature_names));
790
791 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
792 struct btrfs_feature_attr *sfa;
793 struct attribute *a = btrfs_supported_feature_attrs[i];
794 int bit;
795 sfa = attr_to_btrfs_feature_attr(a);
796 bit = ilog2(sfa->feature_bit);
797 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
798
799 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
800 }
801
802 for (set = 0; set < FEAT_MAX; set++) {
803 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
804 char *name = btrfs_unknown_feature_names[set][i];
805 fa = &btrfs_feature_attrs[set][i];
806
807 if (fa->kobj_attr.attr.name)
808 continue;
809
810 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
811 btrfs_feature_set_names[set], i);
812
813 fa->kobj_attr.attr.name = name;
814 fa->kobj_attr.attr.mode = S_IRUGO;
815 fa->feature_set = set;
816 fa->feature_bit = 1ULL << i;
817 }
818 }
819}
820
821/*
822 * Create a sysfs entry for a given block group type at path
823 * /sys/fs/btrfs/UUID/allocation/data/TYPE
824 */
825void btrfs_sysfs_add_block_group_type(struct btrfs_block_group_cache *cache)
826{
827 struct btrfs_fs_info *fs_info = cache->fs_info;
828 struct btrfs_space_info *space_info = cache->space_info;
829 struct raid_kobject *rkobj;
830 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
831 unsigned int nofs_flag;
832 int ret;
833
834 /*
835 * Setup a NOFS context because kobject_add(), deep in its call chain,
836 * does GFP_KERNEL allocations, and we are often called in a context
837 * where if reclaim is triggered we can deadlock (we are either holding
838 * a transaction handle or some lock required for a transaction
839 * commit).
840 */
841 nofs_flag = memalloc_nofs_save();
842
843 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
844 if (!rkobj) {
845 memalloc_nofs_restore(nofs_flag);
846 btrfs_warn(cache->fs_info,
847 "couldn't alloc memory for raid level kobject");
848 return;
849 }
850
851 rkobj->flags = cache->flags;
852 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
853 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
854 btrfs_bg_type_to_raid_name(rkobj->flags));
855 memalloc_nofs_restore(nofs_flag);
856 if (ret) {
857 kobject_put(&rkobj->kobj);
858 btrfs_warn(fs_info,
859 "failed to add kobject for block cache, ignoring");
860 return;
861 }
862
863 space_info->block_group_kobjs[index] = &rkobj->kobj;
864}
865
866/*
867 * Remove sysfs directories for all block group types of a given space info and
868 * the space info as well
869 */
870void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
871{
872 int i;
873
874 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
875 struct kobject *kobj;
876
877 kobj = space_info->block_group_kobjs[i];
878 space_info->block_group_kobjs[i] = NULL;
879 if (kobj) {
880 kobject_del(kobj);
881 kobject_put(kobj);
882 }
883 }
884 kobject_del(&space_info->kobj);
885 kobject_put(&space_info->kobj);
886}
887
888static const char *alloc_name(u64 flags)
889{
890 switch (flags) {
891 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
892 return "mixed";
893 case BTRFS_BLOCK_GROUP_METADATA:
894 return "metadata";
895 case BTRFS_BLOCK_GROUP_DATA:
896 return "data";
897 case BTRFS_BLOCK_GROUP_SYSTEM:
898 return "system";
899 default:
900 WARN_ON(1);
901 return "invalid-combination";
902 };
903}
904
905/*
906 * Create a sysfs entry for a space info type at path
907 * /sys/fs/btrfs/UUID/allocation/TYPE
908 */
909int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
910 struct btrfs_space_info *space_info)
911{
912 int ret;
913
914 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
915 fs_info->space_info_kobj, "%s",
916 alloc_name(space_info->flags));
917 if (ret) {
918 kobject_put(&space_info->kobj);
919 return ret;
920 }
921
922 return 0;
923}
924
925/* when one_device is NULL, it removes all device links */
926
927int btrfs_sysfs_rm_device_link(struct btrfs_fs_devices *fs_devices,
928 struct btrfs_device *one_device)
929{
930 struct hd_struct *disk;
931 struct kobject *disk_kobj;
932
933 if (!fs_devices->device_dir_kobj)
934 return -EINVAL;
935
936 if (one_device && one_device->bdev) {
937 disk = one_device->bdev->bd_part;
938 disk_kobj = &part_to_dev(disk)->kobj;
939
940 sysfs_remove_link(fs_devices->device_dir_kobj,
941 disk_kobj->name);
942 }
943
944 if (one_device)
945 return 0;
946
947 list_for_each_entry(one_device,
948 &fs_devices->devices, dev_list) {
949 if (!one_device->bdev)
950 continue;
951 disk = one_device->bdev->bd_part;
952 disk_kobj = &part_to_dev(disk)->kobj;
953
954 sysfs_remove_link(fs_devices->device_dir_kobj,
955 disk_kobj->name);
956 }
957
958 return 0;
959}
960
961int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs)
962{
963 if (!fs_devs->device_dir_kobj)
964 fs_devs->device_dir_kobj = kobject_create_and_add("devices",
965 &fs_devs->fsid_kobj);
966
967 if (!fs_devs->device_dir_kobj)
968 return -ENOMEM;
969
970 return 0;
971}
972
973int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices,
974 struct btrfs_device *one_device)
975{
976 int error = 0;
977 struct btrfs_device *dev;
978
979 list_for_each_entry(dev, &fs_devices->devices, dev_list) {
980 struct hd_struct *disk;
981 struct kobject *disk_kobj;
982
983 if (!dev->bdev)
984 continue;
985
986 if (one_device && one_device != dev)
987 continue;
988
989 disk = dev->bdev->bd_part;
990 disk_kobj = &part_to_dev(disk)->kobj;
991
992 error = sysfs_create_link(fs_devices->device_dir_kobj,
993 disk_kobj, disk_kobj->name);
994 if (error)
995 break;
996 }
997
998 return error;
999}
1000
1001void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1002{
1003 int ret;
1004
1005 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1006 if (ret)
1007 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1008 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1009 &disk_to_dev(bdev->bd_disk)->kobj);
1010}
1011
1012void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices,
1013 const u8 *fsid)
1014{
1015 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1016
1017 /*
1018 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1019 * directory
1020 */
1021 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fsid);
1022 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1023 btrfs_warn(fs_devices->fs_info,
1024 "sysfs: failed to create fsid for sprout");
1025}
1026
1027/* /sys/fs/btrfs/ entry */
1028static struct kset *btrfs_kset;
1029
1030/*
1031 * Can be called by the device discovery thread.
1032 * And parent can be specified for seed device
1033 */
1034int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs,
1035 struct kobject *parent)
1036{
1037 int error;
1038
1039 init_completion(&fs_devs->kobj_unregister);
1040 fs_devs->fsid_kobj.kset = btrfs_kset;
1041 error = kobject_init_and_add(&fs_devs->fsid_kobj,
1042 &btrfs_ktype, parent, "%pU", fs_devs->fsid);
1043 if (error) {
1044 kobject_put(&fs_devs->fsid_kobj);
1045 return error;
1046 }
1047
1048 return 0;
1049}
1050
1051int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1052{
1053 int error;
1054 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1055 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1056
1057 btrfs_set_fs_info_ptr(fs_info);
1058
1059 error = btrfs_sysfs_add_device_link(fs_devs, NULL);
1060 if (error)
1061 return error;
1062
1063 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1064 if (error) {
1065 btrfs_sysfs_rm_device_link(fs_devs, NULL);
1066 return error;
1067 }
1068
1069 error = sysfs_create_group(fsid_kobj,
1070 &btrfs_feature_attr_group);
1071 if (error)
1072 goto failure;
1073
1074#ifdef CONFIG_BTRFS_DEBUG
1075 error = sysfs_create_group(fsid_kobj,
1076 &btrfs_debug_feature_attr_group);
1077 if (error)
1078 goto failure;
1079#endif
1080
1081 error = addrm_unknown_feature_attrs(fs_info, true);
1082 if (error)
1083 goto failure;
1084
1085 fs_info->space_info_kobj = kobject_create_and_add("allocation",
1086 fsid_kobj);
1087 if (!fs_info->space_info_kobj) {
1088 error = -ENOMEM;
1089 goto failure;
1090 }
1091
1092 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
1093 if (error)
1094 goto failure;
1095
1096 return 0;
1097failure:
1098 btrfs_sysfs_remove_mounted(fs_info);
1099 return error;
1100}
1101
1102
1103/*
1104 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
1105 * values in superblock. Call after any changes to incompat/compat_ro flags
1106 */
1107void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
1108 u64 bit, enum btrfs_feature_set set)
1109{
1110 struct btrfs_fs_devices *fs_devs;
1111 struct kobject *fsid_kobj;
1112 u64 features;
1113 int ret;
1114
1115 if (!fs_info)
1116 return;
1117
1118 features = get_features(fs_info, set);
1119 ASSERT(bit & supported_feature_masks[set]);
1120
1121 fs_devs = fs_info->fs_devices;
1122 fsid_kobj = &fs_devs->fsid_kobj;
1123
1124 if (!fsid_kobj->state_initialized)
1125 return;
1126
1127 /*
1128 * FIXME: this is too heavy to update just one value, ideally we'd like
1129 * to use sysfs_update_group but some refactoring is needed first.
1130 */
1131 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1132 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
1133}
1134
1135int __init btrfs_init_sysfs(void)
1136{
1137 int ret;
1138
1139 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
1140 if (!btrfs_kset)
1141 return -ENOMEM;
1142
1143 init_feature_attrs();
1144 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1145 if (ret)
1146 goto out2;
1147 ret = sysfs_merge_group(&btrfs_kset->kobj,
1148 &btrfs_static_feature_attr_group);
1149 if (ret)
1150 goto out_remove_group;
1151
1152#ifdef CONFIG_BTRFS_DEBUG
1153 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1154 if (ret)
1155 goto out2;
1156#endif
1157
1158 return 0;
1159
1160out_remove_group:
1161 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1162out2:
1163 kset_unregister(btrfs_kset);
1164
1165 return ret;
1166}
1167
1168void __cold btrfs_exit_sysfs(void)
1169{
1170 sysfs_unmerge_group(&btrfs_kset->kobj,
1171 &btrfs_static_feature_attr_group);
1172 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1173 kset_unregister(btrfs_kset);
1174}
1175
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#include <linux/sched.h>
7#include <linux/sched/mm.h>
8#include <linux/slab.h>
9#include <linux/spinlock.h>
10#include <linux/completion.h>
11#include <linux/bug.h>
12#include <crypto/hash.h>
13
14#include "ctree.h"
15#include "discard.h"
16#include "disk-io.h"
17#include "transaction.h"
18#include "sysfs.h"
19#include "volumes.h"
20#include "space-info.h"
21#include "block-group.h"
22#include "qgroup.h"
23
24struct btrfs_feature_attr {
25 struct kobj_attribute kobj_attr;
26 enum btrfs_feature_set feature_set;
27 u64 feature_bit;
28};
29
30/* For raid type sysfs entries */
31struct raid_kobject {
32 u64 flags;
33 struct kobject kobj;
34};
35
36#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
37{ \
38 .attr = { .name = __stringify(_name), .mode = _mode }, \
39 .show = _show, \
40 .store = _store, \
41}
42
43#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
44 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
45 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
46
47#define BTRFS_ATTR(_prefix, _name, _show) \
48 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
49 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
50
51#define BTRFS_ATTR_PTR(_prefix, _name) \
52 (&btrfs_attr_##_prefix##_##_name.attr)
53
54#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
55static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
56 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
57 btrfs_feature_attr_show, \
58 btrfs_feature_attr_store), \
59 .feature_set = _feature_set, \
60 .feature_bit = _feature_prefix ##_## _feature_bit, \
61}
62#define BTRFS_FEAT_ATTR_PTR(_name) \
63 (&btrfs_attr_features_##_name.kobj_attr.attr)
64
65#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
66 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
67#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
68 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
69#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
70 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
71
72static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
73static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
74
75static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
76{
77 return container_of(a, struct btrfs_feature_attr, kobj_attr);
78}
79
80static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
81{
82 return container_of(attr, struct kobj_attribute, attr);
83}
84
85static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
86 struct attribute *attr)
87{
88 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
89}
90
91static u64 get_features(struct btrfs_fs_info *fs_info,
92 enum btrfs_feature_set set)
93{
94 struct btrfs_super_block *disk_super = fs_info->super_copy;
95 if (set == FEAT_COMPAT)
96 return btrfs_super_compat_flags(disk_super);
97 else if (set == FEAT_COMPAT_RO)
98 return btrfs_super_compat_ro_flags(disk_super);
99 else
100 return btrfs_super_incompat_flags(disk_super);
101}
102
103static void set_features(struct btrfs_fs_info *fs_info,
104 enum btrfs_feature_set set, u64 features)
105{
106 struct btrfs_super_block *disk_super = fs_info->super_copy;
107 if (set == FEAT_COMPAT)
108 btrfs_set_super_compat_flags(disk_super, features);
109 else if (set == FEAT_COMPAT_RO)
110 btrfs_set_super_compat_ro_flags(disk_super, features);
111 else
112 btrfs_set_super_incompat_flags(disk_super, features);
113}
114
115static int can_modify_feature(struct btrfs_feature_attr *fa)
116{
117 int val = 0;
118 u64 set, clear;
119 switch (fa->feature_set) {
120 case FEAT_COMPAT:
121 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
122 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
123 break;
124 case FEAT_COMPAT_RO:
125 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
126 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
127 break;
128 case FEAT_INCOMPAT:
129 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
130 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
131 break;
132 default:
133 pr_warn("btrfs: sysfs: unknown feature set %d\n",
134 fa->feature_set);
135 return 0;
136 }
137
138 if (set & fa->feature_bit)
139 val |= 1;
140 if (clear & fa->feature_bit)
141 val |= 2;
142
143 return val;
144}
145
146static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
147 struct kobj_attribute *a, char *buf)
148{
149 int val = 0;
150 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
151 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
152 if (fs_info) {
153 u64 features = get_features(fs_info, fa->feature_set);
154 if (features & fa->feature_bit)
155 val = 1;
156 } else
157 val = can_modify_feature(fa);
158
159 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
160}
161
162static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
163 struct kobj_attribute *a,
164 const char *buf, size_t count)
165{
166 struct btrfs_fs_info *fs_info;
167 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
168 u64 features, set, clear;
169 unsigned long val;
170 int ret;
171
172 fs_info = to_fs_info(kobj);
173 if (!fs_info)
174 return -EPERM;
175
176 if (sb_rdonly(fs_info->sb))
177 return -EROFS;
178
179 ret = kstrtoul(skip_spaces(buf), 0, &val);
180 if (ret)
181 return ret;
182
183 if (fa->feature_set == FEAT_COMPAT) {
184 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
185 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
186 } else if (fa->feature_set == FEAT_COMPAT_RO) {
187 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
188 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
189 } else {
190 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
191 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
192 }
193
194 features = get_features(fs_info, fa->feature_set);
195
196 /* Nothing to do */
197 if ((val && (features & fa->feature_bit)) ||
198 (!val && !(features & fa->feature_bit)))
199 return count;
200
201 if ((val && !(set & fa->feature_bit)) ||
202 (!val && !(clear & fa->feature_bit))) {
203 btrfs_info(fs_info,
204 "%sabling feature %s on mounted fs is not supported.",
205 val ? "En" : "Dis", fa->kobj_attr.attr.name);
206 return -EPERM;
207 }
208
209 btrfs_info(fs_info, "%s %s feature flag",
210 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
211
212 spin_lock(&fs_info->super_lock);
213 features = get_features(fs_info, fa->feature_set);
214 if (val)
215 features |= fa->feature_bit;
216 else
217 features &= ~fa->feature_bit;
218 set_features(fs_info, fa->feature_set, features);
219 spin_unlock(&fs_info->super_lock);
220
221 /*
222 * We don't want to do full transaction commit from inside sysfs
223 */
224 btrfs_set_pending(fs_info, COMMIT);
225 wake_up_process(fs_info->transaction_kthread);
226
227 return count;
228}
229
230static umode_t btrfs_feature_visible(struct kobject *kobj,
231 struct attribute *attr, int unused)
232{
233 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
234 umode_t mode = attr->mode;
235
236 if (fs_info) {
237 struct btrfs_feature_attr *fa;
238 u64 features;
239
240 fa = attr_to_btrfs_feature_attr(attr);
241 features = get_features(fs_info, fa->feature_set);
242
243 if (can_modify_feature(fa))
244 mode |= S_IWUSR;
245 else if (!(features & fa->feature_bit))
246 mode = 0;
247 }
248
249 return mode;
250}
251
252BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
253BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
254BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
255BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
256BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
257BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
258BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
259BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
260BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
261BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
262BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
263BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
264BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
265
266static struct attribute *btrfs_supported_feature_attrs[] = {
267 BTRFS_FEAT_ATTR_PTR(mixed_backref),
268 BTRFS_FEAT_ATTR_PTR(default_subvol),
269 BTRFS_FEAT_ATTR_PTR(mixed_groups),
270 BTRFS_FEAT_ATTR_PTR(compress_lzo),
271 BTRFS_FEAT_ATTR_PTR(compress_zstd),
272 BTRFS_FEAT_ATTR_PTR(big_metadata),
273 BTRFS_FEAT_ATTR_PTR(extended_iref),
274 BTRFS_FEAT_ATTR_PTR(raid56),
275 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
276 BTRFS_FEAT_ATTR_PTR(no_holes),
277 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
278 BTRFS_FEAT_ATTR_PTR(free_space_tree),
279 BTRFS_FEAT_ATTR_PTR(raid1c34),
280 NULL
281};
282
283/*
284 * Features which depend on feature bits and may differ between each fs.
285 *
286 * /sys/fs/btrfs/features lists all available features of this kernel while
287 * /sys/fs/btrfs/UUID/features shows features of the fs which are enabled or
288 * can be changed online.
289 */
290static const struct attribute_group btrfs_feature_attr_group = {
291 .name = "features",
292 .is_visible = btrfs_feature_visible,
293 .attrs = btrfs_supported_feature_attrs,
294};
295
296static ssize_t rmdir_subvol_show(struct kobject *kobj,
297 struct kobj_attribute *ka, char *buf)
298{
299 return scnprintf(buf, PAGE_SIZE, "0\n");
300}
301BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
302
303static ssize_t supported_checksums_show(struct kobject *kobj,
304 struct kobj_attribute *a, char *buf)
305{
306 ssize_t ret = 0;
307 int i;
308
309 for (i = 0; i < btrfs_get_num_csums(); i++) {
310 /*
311 * This "trick" only works as long as 'enum btrfs_csum_type' has
312 * no holes in it
313 */
314 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
315 (i == 0 ? "" : " "), btrfs_super_csum_name(i));
316
317 }
318
319 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
320 return ret;
321}
322BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
323
324static struct attribute *btrfs_supported_static_feature_attrs[] = {
325 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
326 BTRFS_ATTR_PTR(static_feature, supported_checksums),
327 NULL
328};
329
330/*
331 * Features which only depend on kernel version.
332 *
333 * These are listed in /sys/fs/btrfs/features along with
334 * btrfs_feature_attr_group
335 */
336static const struct attribute_group btrfs_static_feature_attr_group = {
337 .name = "features",
338 .attrs = btrfs_supported_static_feature_attrs,
339};
340
341#ifdef CONFIG_BTRFS_DEBUG
342
343/*
344 * Discard statistics and tunables
345 */
346#define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent)
347
348static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
349 struct kobj_attribute *a,
350 char *buf)
351{
352 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
353
354 return scnprintf(buf, PAGE_SIZE, "%lld\n",
355 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
356}
357BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
358
359static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
360 struct kobj_attribute *a,
361 char *buf)
362{
363 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
364
365 return scnprintf(buf, PAGE_SIZE, "%d\n",
366 atomic_read(&fs_info->discard_ctl.discardable_extents));
367}
368BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
369
370static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
371 struct kobj_attribute *a,
372 char *buf)
373{
374 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
375
376 return scnprintf(buf, PAGE_SIZE, "%lld\n",
377 fs_info->discard_ctl.discard_bitmap_bytes);
378}
379BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
380
381static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
382 struct kobj_attribute *a,
383 char *buf)
384{
385 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
386
387 return scnprintf(buf, PAGE_SIZE, "%lld\n",
388 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
389}
390BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
391
392static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
393 struct kobj_attribute *a,
394 char *buf)
395{
396 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
397
398 return scnprintf(buf, PAGE_SIZE, "%lld\n",
399 fs_info->discard_ctl.discard_extent_bytes);
400}
401BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
402
403static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
404 struct kobj_attribute *a,
405 char *buf)
406{
407 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
408
409 return scnprintf(buf, PAGE_SIZE, "%u\n",
410 READ_ONCE(fs_info->discard_ctl.iops_limit));
411}
412
413static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
414 struct kobj_attribute *a,
415 const char *buf, size_t len)
416{
417 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
418 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
419 u32 iops_limit;
420 int ret;
421
422 ret = kstrtou32(buf, 10, &iops_limit);
423 if (ret)
424 return -EINVAL;
425
426 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
427
428 return len;
429}
430BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
431 btrfs_discard_iops_limit_store);
432
433static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
434 struct kobj_attribute *a,
435 char *buf)
436{
437 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
438
439 return scnprintf(buf, PAGE_SIZE, "%u\n",
440 READ_ONCE(fs_info->discard_ctl.kbps_limit));
441}
442
443static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
444 struct kobj_attribute *a,
445 const char *buf, size_t len)
446{
447 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
448 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
449 u32 kbps_limit;
450 int ret;
451
452 ret = kstrtou32(buf, 10, &kbps_limit);
453 if (ret)
454 return -EINVAL;
455
456 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
457
458 return len;
459}
460BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
461 btrfs_discard_kbps_limit_store);
462
463static ssize_t btrfs_discard_max_discard_size_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 scnprintf(buf, PAGE_SIZE, "%llu\n",
470 READ_ONCE(fs_info->discard_ctl.max_discard_size));
471}
472
473static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
474 struct kobj_attribute *a,
475 const char *buf, size_t len)
476{
477 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
478 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
479 u64 max_discard_size;
480 int ret;
481
482 ret = kstrtou64(buf, 10, &max_discard_size);
483 if (ret)
484 return -EINVAL;
485
486 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
487
488 return len;
489}
490BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
491 btrfs_discard_max_discard_size_store);
492
493static const struct attribute *discard_debug_attrs[] = {
494 BTRFS_ATTR_PTR(discard, discardable_bytes),
495 BTRFS_ATTR_PTR(discard, discardable_extents),
496 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
497 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
498 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
499 BTRFS_ATTR_PTR(discard, iops_limit),
500 BTRFS_ATTR_PTR(discard, kbps_limit),
501 BTRFS_ATTR_PTR(discard, max_discard_size),
502 NULL,
503};
504
505/*
506 * Runtime debugging exported via sysfs
507 *
508 * /sys/fs/btrfs/debug - applies to module or all filesystems
509 * /sys/fs/btrfs/UUID - applies only to the given filesystem
510 */
511static const struct attribute *btrfs_debug_mount_attrs[] = {
512 NULL,
513};
514
515static struct attribute *btrfs_debug_feature_attrs[] = {
516 NULL
517};
518
519static const struct attribute_group btrfs_debug_feature_attr_group = {
520 .name = "debug",
521 .attrs = btrfs_debug_feature_attrs,
522};
523
524#endif
525
526static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
527{
528 u64 val;
529 if (lock)
530 spin_lock(lock);
531 val = *value_ptr;
532 if (lock)
533 spin_unlock(lock);
534 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
535}
536
537static ssize_t global_rsv_size_show(struct kobject *kobj,
538 struct kobj_attribute *ka, char *buf)
539{
540 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
541 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
542 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
543}
544BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
545
546static ssize_t global_rsv_reserved_show(struct kobject *kobj,
547 struct kobj_attribute *a, char *buf)
548{
549 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
550 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
551 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
552}
553BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
554
555#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
556#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
557
558static ssize_t raid_bytes_show(struct kobject *kobj,
559 struct kobj_attribute *attr, char *buf);
560BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
561BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
562
563static ssize_t raid_bytes_show(struct kobject *kobj,
564 struct kobj_attribute *attr, char *buf)
565
566{
567 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
568 struct btrfs_block_group *block_group;
569 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
570 u64 val = 0;
571
572 down_read(&sinfo->groups_sem);
573 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
574 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
575 val += block_group->length;
576 else
577 val += block_group->used;
578 }
579 up_read(&sinfo->groups_sem);
580 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
581}
582
583static struct attribute *raid_attrs[] = {
584 BTRFS_ATTR_PTR(raid, total_bytes),
585 BTRFS_ATTR_PTR(raid, used_bytes),
586 NULL
587};
588ATTRIBUTE_GROUPS(raid);
589
590static void release_raid_kobj(struct kobject *kobj)
591{
592 kfree(to_raid_kobj(kobj));
593}
594
595static struct kobj_type btrfs_raid_ktype = {
596 .sysfs_ops = &kobj_sysfs_ops,
597 .release = release_raid_kobj,
598 .default_groups = raid_groups,
599};
600
601#define SPACE_INFO_ATTR(field) \
602static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
603 struct kobj_attribute *a, \
604 char *buf) \
605{ \
606 struct btrfs_space_info *sinfo = to_space_info(kobj); \
607 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
608} \
609BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
610
611static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
612 struct kobj_attribute *a,
613 char *buf)
614{
615 struct btrfs_space_info *sinfo = to_space_info(kobj);
616 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
617 return scnprintf(buf, PAGE_SIZE, "%lld\n", val);
618}
619
620SPACE_INFO_ATTR(flags);
621SPACE_INFO_ATTR(total_bytes);
622SPACE_INFO_ATTR(bytes_used);
623SPACE_INFO_ATTR(bytes_pinned);
624SPACE_INFO_ATTR(bytes_reserved);
625SPACE_INFO_ATTR(bytes_may_use);
626SPACE_INFO_ATTR(bytes_readonly);
627SPACE_INFO_ATTR(disk_used);
628SPACE_INFO_ATTR(disk_total);
629BTRFS_ATTR(space_info, total_bytes_pinned,
630 btrfs_space_info_show_total_bytes_pinned);
631
632static struct attribute *space_info_attrs[] = {
633 BTRFS_ATTR_PTR(space_info, flags),
634 BTRFS_ATTR_PTR(space_info, total_bytes),
635 BTRFS_ATTR_PTR(space_info, bytes_used),
636 BTRFS_ATTR_PTR(space_info, bytes_pinned),
637 BTRFS_ATTR_PTR(space_info, bytes_reserved),
638 BTRFS_ATTR_PTR(space_info, bytes_may_use),
639 BTRFS_ATTR_PTR(space_info, bytes_readonly),
640 BTRFS_ATTR_PTR(space_info, disk_used),
641 BTRFS_ATTR_PTR(space_info, disk_total),
642 BTRFS_ATTR_PTR(space_info, total_bytes_pinned),
643 NULL,
644};
645ATTRIBUTE_GROUPS(space_info);
646
647static void space_info_release(struct kobject *kobj)
648{
649 struct btrfs_space_info *sinfo = to_space_info(kobj);
650 percpu_counter_destroy(&sinfo->total_bytes_pinned);
651 kfree(sinfo);
652}
653
654static struct kobj_type space_info_ktype = {
655 .sysfs_ops = &kobj_sysfs_ops,
656 .release = space_info_release,
657 .default_groups = space_info_groups,
658};
659
660static const struct attribute *allocation_attrs[] = {
661 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
662 BTRFS_ATTR_PTR(allocation, global_rsv_size),
663 NULL,
664};
665
666static ssize_t btrfs_label_show(struct kobject *kobj,
667 struct kobj_attribute *a, char *buf)
668{
669 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
670 char *label = fs_info->super_copy->label;
671 ssize_t ret;
672
673 spin_lock(&fs_info->super_lock);
674 ret = scnprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
675 spin_unlock(&fs_info->super_lock);
676
677 return ret;
678}
679
680static ssize_t btrfs_label_store(struct kobject *kobj,
681 struct kobj_attribute *a,
682 const char *buf, size_t len)
683{
684 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
685 size_t p_len;
686
687 if (!fs_info)
688 return -EPERM;
689
690 if (sb_rdonly(fs_info->sb))
691 return -EROFS;
692
693 /*
694 * p_len is the len until the first occurrence of either
695 * '\n' or '\0'
696 */
697 p_len = strcspn(buf, "\n");
698
699 if (p_len >= BTRFS_LABEL_SIZE)
700 return -EINVAL;
701
702 spin_lock(&fs_info->super_lock);
703 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
704 memcpy(fs_info->super_copy->label, buf, p_len);
705 spin_unlock(&fs_info->super_lock);
706
707 /*
708 * We don't want to do full transaction commit from inside sysfs
709 */
710 btrfs_set_pending(fs_info, COMMIT);
711 wake_up_process(fs_info->transaction_kthread);
712
713 return len;
714}
715BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
716
717static ssize_t btrfs_nodesize_show(struct kobject *kobj,
718 struct kobj_attribute *a, char *buf)
719{
720 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
721
722 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
723}
724
725BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
726
727static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
728 struct kobj_attribute *a, char *buf)
729{
730 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
731
732 return scnprintf(buf, PAGE_SIZE, "%u\n",
733 fs_info->super_copy->sectorsize);
734}
735
736BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
737
738static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
739 struct kobj_attribute *a, char *buf)
740{
741 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
742
743 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
744}
745
746BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
747
748static ssize_t quota_override_show(struct kobject *kobj,
749 struct kobj_attribute *a, char *buf)
750{
751 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
752 int quota_override;
753
754 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
755 return scnprintf(buf, PAGE_SIZE, "%d\n", quota_override);
756}
757
758static ssize_t quota_override_store(struct kobject *kobj,
759 struct kobj_attribute *a,
760 const char *buf, size_t len)
761{
762 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
763 unsigned long knob;
764 int err;
765
766 if (!fs_info)
767 return -EPERM;
768
769 if (!capable(CAP_SYS_RESOURCE))
770 return -EPERM;
771
772 err = kstrtoul(buf, 10, &knob);
773 if (err)
774 return err;
775 if (knob > 1)
776 return -EINVAL;
777
778 if (knob)
779 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
780 else
781 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
782
783 return len;
784}
785
786BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
787
788static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
789 struct kobj_attribute *a, char *buf)
790{
791 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
792
793 return scnprintf(buf, PAGE_SIZE, "%pU\n",
794 fs_info->fs_devices->metadata_uuid);
795}
796
797BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
798
799static ssize_t btrfs_checksum_show(struct kobject *kobj,
800 struct kobj_attribute *a, char *buf)
801{
802 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
803 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
804
805 return scnprintf(buf, PAGE_SIZE, "%s (%s)\n",
806 btrfs_super_csum_name(csum_type),
807 crypto_shash_driver_name(fs_info->csum_shash));
808}
809
810BTRFS_ATTR(, checksum, btrfs_checksum_show);
811
812static const struct attribute *btrfs_attrs[] = {
813 BTRFS_ATTR_PTR(, label),
814 BTRFS_ATTR_PTR(, nodesize),
815 BTRFS_ATTR_PTR(, sectorsize),
816 BTRFS_ATTR_PTR(, clone_alignment),
817 BTRFS_ATTR_PTR(, quota_override),
818 BTRFS_ATTR_PTR(, metadata_uuid),
819 BTRFS_ATTR_PTR(, checksum),
820 NULL,
821};
822
823static void btrfs_release_fsid_kobj(struct kobject *kobj)
824{
825 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
826
827 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
828 complete(&fs_devs->kobj_unregister);
829}
830
831static struct kobj_type btrfs_ktype = {
832 .sysfs_ops = &kobj_sysfs_ops,
833 .release = btrfs_release_fsid_kobj,
834};
835
836static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
837{
838 if (kobj->ktype != &btrfs_ktype)
839 return NULL;
840 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
841}
842
843static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
844{
845 if (kobj->ktype != &btrfs_ktype)
846 return NULL;
847 return to_fs_devs(kobj)->fs_info;
848}
849
850#define NUM_FEATURE_BITS 64
851#define BTRFS_FEATURE_NAME_MAX 13
852static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
853static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
854
855static const u64 supported_feature_masks[FEAT_MAX] = {
856 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
857 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
858 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
859};
860
861static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
862{
863 int set;
864
865 for (set = 0; set < FEAT_MAX; set++) {
866 int i;
867 struct attribute *attrs[2];
868 struct attribute_group agroup = {
869 .name = "features",
870 .attrs = attrs,
871 };
872 u64 features = get_features(fs_info, set);
873 features &= ~supported_feature_masks[set];
874
875 if (!features)
876 continue;
877
878 attrs[1] = NULL;
879 for (i = 0; i < NUM_FEATURE_BITS; i++) {
880 struct btrfs_feature_attr *fa;
881
882 if (!(features & (1ULL << i)))
883 continue;
884
885 fa = &btrfs_feature_attrs[set][i];
886 attrs[0] = &fa->kobj_attr.attr;
887 if (add) {
888 int ret;
889 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
890 &agroup);
891 if (ret)
892 return ret;
893 } else
894 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
895 &agroup);
896 }
897
898 }
899 return 0;
900}
901
902static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
903{
904 if (fs_devs->devinfo_kobj) {
905 kobject_del(fs_devs->devinfo_kobj);
906 kobject_put(fs_devs->devinfo_kobj);
907 fs_devs->devinfo_kobj = NULL;
908 }
909
910 if (fs_devs->devices_kobj) {
911 kobject_del(fs_devs->devices_kobj);
912 kobject_put(fs_devs->devices_kobj);
913 fs_devs->devices_kobj = NULL;
914 }
915
916 if (fs_devs->fsid_kobj.state_initialized) {
917 kobject_del(&fs_devs->fsid_kobj);
918 kobject_put(&fs_devs->fsid_kobj);
919 wait_for_completion(&fs_devs->kobj_unregister);
920 }
921}
922
923/* when fs_devs is NULL it will remove all fsid kobject */
924void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
925{
926 struct list_head *fs_uuids = btrfs_get_fs_uuids();
927
928 if (fs_devs) {
929 __btrfs_sysfs_remove_fsid(fs_devs);
930 return;
931 }
932
933 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
934 __btrfs_sysfs_remove_fsid(fs_devs);
935 }
936}
937
938void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
939{
940 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
941
942 btrfs_reset_fs_info_ptr(fs_info);
943
944 sysfs_remove_link(fsid_kobj, "bdi");
945
946 if (fs_info->space_info_kobj) {
947 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
948 kobject_del(fs_info->space_info_kobj);
949 kobject_put(fs_info->space_info_kobj);
950 }
951#ifdef CONFIG_BTRFS_DEBUG
952 if (fs_info->discard_debug_kobj) {
953 sysfs_remove_files(fs_info->discard_debug_kobj,
954 discard_debug_attrs);
955 kobject_del(fs_info->discard_debug_kobj);
956 kobject_put(fs_info->discard_debug_kobj);
957 }
958 if (fs_info->debug_kobj) {
959 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
960 kobject_del(fs_info->debug_kobj);
961 kobject_put(fs_info->debug_kobj);
962 }
963#endif
964 addrm_unknown_feature_attrs(fs_info, false);
965 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
966 sysfs_remove_files(fsid_kobj, btrfs_attrs);
967 btrfs_sysfs_remove_devices_dir(fs_info->fs_devices, NULL);
968}
969
970static const char * const btrfs_feature_set_names[FEAT_MAX] = {
971 [FEAT_COMPAT] = "compat",
972 [FEAT_COMPAT_RO] = "compat_ro",
973 [FEAT_INCOMPAT] = "incompat",
974};
975
976const char * const btrfs_feature_set_name(enum btrfs_feature_set set)
977{
978 return btrfs_feature_set_names[set];
979}
980
981char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
982{
983 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
984 int len = 0;
985 int i;
986 char *str;
987
988 str = kmalloc(bufsize, GFP_KERNEL);
989 if (!str)
990 return str;
991
992 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
993 const char *name;
994
995 if (!(flags & (1ULL << i)))
996 continue;
997
998 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
999 len += scnprintf(str + len, bufsize - len, "%s%s",
1000 len ? "," : "", name);
1001 }
1002
1003 return str;
1004}
1005
1006static void init_feature_attrs(void)
1007{
1008 struct btrfs_feature_attr *fa;
1009 int set, i;
1010
1011 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
1012 ARRAY_SIZE(btrfs_feature_attrs));
1013 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
1014 ARRAY_SIZE(btrfs_feature_attrs[0]));
1015
1016 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1017 memset(btrfs_unknown_feature_names, 0,
1018 sizeof(btrfs_unknown_feature_names));
1019
1020 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1021 struct btrfs_feature_attr *sfa;
1022 struct attribute *a = btrfs_supported_feature_attrs[i];
1023 int bit;
1024 sfa = attr_to_btrfs_feature_attr(a);
1025 bit = ilog2(sfa->feature_bit);
1026 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1027
1028 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1029 }
1030
1031 for (set = 0; set < FEAT_MAX; set++) {
1032 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1033 char *name = btrfs_unknown_feature_names[set][i];
1034 fa = &btrfs_feature_attrs[set][i];
1035
1036 if (fa->kobj_attr.attr.name)
1037 continue;
1038
1039 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1040 btrfs_feature_set_names[set], i);
1041
1042 fa->kobj_attr.attr.name = name;
1043 fa->kobj_attr.attr.mode = S_IRUGO;
1044 fa->feature_set = set;
1045 fa->feature_bit = 1ULL << i;
1046 }
1047 }
1048}
1049
1050/*
1051 * Create a sysfs entry for a given block group type at path
1052 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1053 */
1054void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1055{
1056 struct btrfs_fs_info *fs_info = cache->fs_info;
1057 struct btrfs_space_info *space_info = cache->space_info;
1058 struct raid_kobject *rkobj;
1059 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1060 unsigned int nofs_flag;
1061 int ret;
1062
1063 /*
1064 * Setup a NOFS context because kobject_add(), deep in its call chain,
1065 * does GFP_KERNEL allocations, and we are often called in a context
1066 * where if reclaim is triggered we can deadlock (we are either holding
1067 * a transaction handle or some lock required for a transaction
1068 * commit).
1069 */
1070 nofs_flag = memalloc_nofs_save();
1071
1072 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1073 if (!rkobj) {
1074 memalloc_nofs_restore(nofs_flag);
1075 btrfs_warn(cache->fs_info,
1076 "couldn't alloc memory for raid level kobject");
1077 return;
1078 }
1079
1080 rkobj->flags = cache->flags;
1081 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1082 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1083 btrfs_bg_type_to_raid_name(rkobj->flags));
1084 memalloc_nofs_restore(nofs_flag);
1085 if (ret) {
1086 kobject_put(&rkobj->kobj);
1087 btrfs_warn(fs_info,
1088 "failed to add kobject for block cache, ignoring");
1089 return;
1090 }
1091
1092 space_info->block_group_kobjs[index] = &rkobj->kobj;
1093}
1094
1095/*
1096 * Remove sysfs directories for all block group types of a given space info and
1097 * the space info as well
1098 */
1099void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1100{
1101 int i;
1102
1103 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1104 struct kobject *kobj;
1105
1106 kobj = space_info->block_group_kobjs[i];
1107 space_info->block_group_kobjs[i] = NULL;
1108 if (kobj) {
1109 kobject_del(kobj);
1110 kobject_put(kobj);
1111 }
1112 }
1113 kobject_del(&space_info->kobj);
1114 kobject_put(&space_info->kobj);
1115}
1116
1117static const char *alloc_name(u64 flags)
1118{
1119 switch (flags) {
1120 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1121 return "mixed";
1122 case BTRFS_BLOCK_GROUP_METADATA:
1123 return "metadata";
1124 case BTRFS_BLOCK_GROUP_DATA:
1125 return "data";
1126 case BTRFS_BLOCK_GROUP_SYSTEM:
1127 return "system";
1128 default:
1129 WARN_ON(1);
1130 return "invalid-combination";
1131 };
1132}
1133
1134/*
1135 * Create a sysfs entry for a space info type at path
1136 * /sys/fs/btrfs/UUID/allocation/TYPE
1137 */
1138int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1139 struct btrfs_space_info *space_info)
1140{
1141 int ret;
1142
1143 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1144 fs_info->space_info_kobj, "%s",
1145 alloc_name(space_info->flags));
1146 if (ret) {
1147 kobject_put(&space_info->kobj);
1148 return ret;
1149 }
1150
1151 return 0;
1152}
1153
1154/* when one_device is NULL, it removes all device links */
1155
1156int btrfs_sysfs_remove_devices_dir(struct btrfs_fs_devices *fs_devices,
1157 struct btrfs_device *one_device)
1158{
1159 struct hd_struct *disk;
1160 struct kobject *disk_kobj;
1161
1162 if (!fs_devices->devices_kobj)
1163 return -EINVAL;
1164
1165 if (one_device) {
1166 if (one_device->bdev) {
1167 disk = one_device->bdev->bd_part;
1168 disk_kobj = &part_to_dev(disk)->kobj;
1169 sysfs_remove_link(fs_devices->devices_kobj,
1170 disk_kobj->name);
1171 }
1172
1173 if (one_device->devid_kobj.state_initialized) {
1174 kobject_del(&one_device->devid_kobj);
1175 kobject_put(&one_device->devid_kobj);
1176
1177 wait_for_completion(&one_device->kobj_unregister);
1178 }
1179
1180 return 0;
1181 }
1182
1183 list_for_each_entry(one_device, &fs_devices->devices, dev_list) {
1184
1185 if (one_device->bdev) {
1186 disk = one_device->bdev->bd_part;
1187 disk_kobj = &part_to_dev(disk)->kobj;
1188 sysfs_remove_link(fs_devices->devices_kobj,
1189 disk_kobj->name);
1190 }
1191 if (one_device->devid_kobj.state_initialized) {
1192 kobject_del(&one_device->devid_kobj);
1193 kobject_put(&one_device->devid_kobj);
1194
1195 wait_for_completion(&one_device->kobj_unregister);
1196 }
1197 }
1198
1199 return 0;
1200}
1201
1202static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1203 struct kobj_attribute *a,
1204 char *buf)
1205{
1206 int val;
1207 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1208 devid_kobj);
1209
1210 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1211
1212 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1213}
1214BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1215
1216static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1217 struct kobj_attribute *a, char *buf)
1218{
1219 int val;
1220 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1221 devid_kobj);
1222
1223 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1224
1225 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1226}
1227BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1228
1229static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1230 struct kobj_attribute *a,
1231 char *buf)
1232{
1233 int val;
1234 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1235 devid_kobj);
1236
1237 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1238
1239 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1240}
1241BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1242
1243static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1244 struct kobj_attribute *a, char *buf)
1245{
1246 int val;
1247 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1248 devid_kobj);
1249
1250 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1251
1252 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1253}
1254BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1255
1256static struct attribute *devid_attrs[] = {
1257 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1258 BTRFS_ATTR_PTR(devid, missing),
1259 BTRFS_ATTR_PTR(devid, replace_target),
1260 BTRFS_ATTR_PTR(devid, writeable),
1261 NULL
1262};
1263ATTRIBUTE_GROUPS(devid);
1264
1265static void btrfs_release_devid_kobj(struct kobject *kobj)
1266{
1267 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1268 devid_kobj);
1269
1270 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1271 complete(&device->kobj_unregister);
1272}
1273
1274static struct kobj_type devid_ktype = {
1275 .sysfs_ops = &kobj_sysfs_ops,
1276 .default_groups = devid_groups,
1277 .release = btrfs_release_devid_kobj,
1278};
1279
1280int btrfs_sysfs_add_devices_dir(struct btrfs_fs_devices *fs_devices,
1281 struct btrfs_device *one_device)
1282{
1283 int error = 0;
1284 struct btrfs_device *dev;
1285 unsigned int nofs_flag;
1286
1287 nofs_flag = memalloc_nofs_save();
1288 list_for_each_entry(dev, &fs_devices->devices, dev_list) {
1289
1290 if (one_device && one_device != dev)
1291 continue;
1292
1293 if (dev->bdev) {
1294 struct hd_struct *disk;
1295 struct kobject *disk_kobj;
1296
1297 disk = dev->bdev->bd_part;
1298 disk_kobj = &part_to_dev(disk)->kobj;
1299
1300 error = sysfs_create_link(fs_devices->devices_kobj,
1301 disk_kobj, disk_kobj->name);
1302 if (error)
1303 break;
1304 }
1305
1306 init_completion(&dev->kobj_unregister);
1307 error = kobject_init_and_add(&dev->devid_kobj, &devid_ktype,
1308 fs_devices->devinfo_kobj, "%llu",
1309 dev->devid);
1310 if (error) {
1311 kobject_put(&dev->devid_kobj);
1312 break;
1313 }
1314 }
1315 memalloc_nofs_restore(nofs_flag);
1316
1317 return error;
1318}
1319
1320void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1321{
1322 int ret;
1323
1324 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1325 if (ret)
1326 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1327 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1328 &disk_to_dev(bdev->bd_disk)->kobj);
1329}
1330
1331void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices,
1332 const u8 *fsid)
1333{
1334 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1335
1336 /*
1337 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1338 * directory
1339 */
1340 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fsid);
1341 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1342 btrfs_warn(fs_devices->fs_info,
1343 "sysfs: failed to create fsid for sprout");
1344}
1345
1346void btrfs_sysfs_update_devid(struct btrfs_device *device)
1347{
1348 char tmp[24];
1349
1350 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
1351
1352 if (kobject_rename(&device->devid_kobj, tmp))
1353 btrfs_warn(device->fs_devices->fs_info,
1354 "sysfs: failed to update devid for %llu",
1355 device->devid);
1356}
1357
1358/* /sys/fs/btrfs/ entry */
1359static struct kset *btrfs_kset;
1360
1361/*
1362 * Creates:
1363 * /sys/fs/btrfs/UUID
1364 *
1365 * Can be called by the device discovery thread.
1366 */
1367int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
1368{
1369 int error;
1370
1371 init_completion(&fs_devs->kobj_unregister);
1372 fs_devs->fsid_kobj.kset = btrfs_kset;
1373 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
1374 "%pU", fs_devs->fsid);
1375 if (error) {
1376 kobject_put(&fs_devs->fsid_kobj);
1377 return error;
1378 }
1379
1380 fs_devs->devices_kobj = kobject_create_and_add("devices",
1381 &fs_devs->fsid_kobj);
1382 if (!fs_devs->devices_kobj) {
1383 btrfs_err(fs_devs->fs_info,
1384 "failed to init sysfs device interface");
1385 btrfs_sysfs_remove_fsid(fs_devs);
1386 return -ENOMEM;
1387 }
1388
1389 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
1390 &fs_devs->fsid_kobj);
1391 if (!fs_devs->devinfo_kobj) {
1392 btrfs_err(fs_devs->fs_info,
1393 "failed to init sysfs devinfo kobject");
1394 btrfs_sysfs_remove_fsid(fs_devs);
1395 return -ENOMEM;
1396 }
1397
1398 return 0;
1399}
1400
1401int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1402{
1403 int error;
1404 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1405 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1406
1407 btrfs_set_fs_info_ptr(fs_info);
1408
1409 error = btrfs_sysfs_add_devices_dir(fs_devs, NULL);
1410 if (error)
1411 return error;
1412
1413 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1414 if (error) {
1415 btrfs_sysfs_remove_devices_dir(fs_devs, NULL);
1416 return error;
1417 }
1418
1419 error = sysfs_create_group(fsid_kobj,
1420 &btrfs_feature_attr_group);
1421 if (error)
1422 goto failure;
1423
1424#ifdef CONFIG_BTRFS_DEBUG
1425 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
1426 if (!fs_info->debug_kobj) {
1427 error = -ENOMEM;
1428 goto failure;
1429 }
1430
1431 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1432 if (error)
1433 goto failure;
1434
1435 /* Discard directory */
1436 fs_info->discard_debug_kobj = kobject_create_and_add("discard",
1437 fs_info->debug_kobj);
1438 if (!fs_info->discard_debug_kobj) {
1439 error = -ENOMEM;
1440 goto failure;
1441 }
1442
1443 error = sysfs_create_files(fs_info->discard_debug_kobj,
1444 discard_debug_attrs);
1445 if (error)
1446 goto failure;
1447#endif
1448
1449 error = addrm_unknown_feature_attrs(fs_info, true);
1450 if (error)
1451 goto failure;
1452
1453 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
1454 if (error)
1455 goto failure;
1456
1457 fs_info->space_info_kobj = kobject_create_and_add("allocation",
1458 fsid_kobj);
1459 if (!fs_info->space_info_kobj) {
1460 error = -ENOMEM;
1461 goto failure;
1462 }
1463
1464 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
1465 if (error)
1466 goto failure;
1467
1468 return 0;
1469failure:
1470 btrfs_sysfs_remove_mounted(fs_info);
1471 return error;
1472}
1473
1474static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
1475{
1476 return to_fs_info(kobj->parent->parent);
1477}
1478
1479#define QGROUP_ATTR(_member, _show_name) \
1480static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
1481 struct kobj_attribute *a, \
1482 char *buf) \
1483{ \
1484 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1485 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1486 struct btrfs_qgroup, kobj); \
1487 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
1488} \
1489BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
1490
1491#define QGROUP_RSV_ATTR(_name, _type) \
1492static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
1493 struct kobj_attribute *a, \
1494 char *buf) \
1495{ \
1496 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1497 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1498 struct btrfs_qgroup, kobj); \
1499 return btrfs_show_u64(&qgroup->rsv.values[_type], \
1500 &fs_info->qgroup_lock, buf); \
1501} \
1502BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
1503
1504QGROUP_ATTR(rfer, referenced);
1505QGROUP_ATTR(excl, exclusive);
1506QGROUP_ATTR(max_rfer, max_referenced);
1507QGROUP_ATTR(max_excl, max_exclusive);
1508QGROUP_ATTR(lim_flags, limit_flags);
1509QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
1510QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
1511QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
1512
1513static struct attribute *qgroup_attrs[] = {
1514 BTRFS_ATTR_PTR(qgroup, referenced),
1515 BTRFS_ATTR_PTR(qgroup, exclusive),
1516 BTRFS_ATTR_PTR(qgroup, max_referenced),
1517 BTRFS_ATTR_PTR(qgroup, max_exclusive),
1518 BTRFS_ATTR_PTR(qgroup, limit_flags),
1519 BTRFS_ATTR_PTR(qgroup, rsv_data),
1520 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
1521 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
1522 NULL
1523};
1524ATTRIBUTE_GROUPS(qgroup);
1525
1526static void qgroup_release(struct kobject *kobj)
1527{
1528 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
1529
1530 memset(&qgroup->kobj, 0, sizeof(*kobj));
1531}
1532
1533static struct kobj_type qgroup_ktype = {
1534 .sysfs_ops = &kobj_sysfs_ops,
1535 .release = qgroup_release,
1536 .default_groups = qgroup_groups,
1537};
1538
1539int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
1540 struct btrfs_qgroup *qgroup)
1541{
1542 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
1543 int ret;
1544
1545 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1546 return 0;
1547 if (qgroup->kobj.state_initialized)
1548 return 0;
1549 if (!qgroups_kobj)
1550 return -EINVAL;
1551
1552 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
1553 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
1554 btrfs_qgroup_subvolid(qgroup->qgroupid));
1555 if (ret < 0)
1556 kobject_put(&qgroup->kobj);
1557
1558 return ret;
1559}
1560
1561void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
1562{
1563 struct btrfs_qgroup *qgroup;
1564 struct btrfs_qgroup *next;
1565
1566 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1567 return;
1568
1569 rbtree_postorder_for_each_entry_safe(qgroup, next,
1570 &fs_info->qgroup_tree, node)
1571 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1572 if (fs_info->qgroups_kobj) {
1573 kobject_del(fs_info->qgroups_kobj);
1574 kobject_put(fs_info->qgroups_kobj);
1575 fs_info->qgroups_kobj = NULL;
1576 }
1577}
1578
1579/* Called when qgroups get initialized, thus there is no need for locking */
1580int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
1581{
1582 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1583 struct btrfs_qgroup *qgroup;
1584 struct btrfs_qgroup *next;
1585 int ret = 0;
1586
1587 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1588 return 0;
1589
1590 ASSERT(fsid_kobj);
1591 if (fs_info->qgroups_kobj)
1592 return 0;
1593
1594 fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj);
1595 if (!fs_info->qgroups_kobj) {
1596 ret = -ENOMEM;
1597 goto out;
1598 }
1599 rbtree_postorder_for_each_entry_safe(qgroup, next,
1600 &fs_info->qgroup_tree, node) {
1601 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1602 if (ret < 0)
1603 goto out;
1604 }
1605
1606out:
1607 if (ret < 0)
1608 btrfs_sysfs_del_qgroups(fs_info);
1609 return ret;
1610}
1611
1612void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
1613 struct btrfs_qgroup *qgroup)
1614{
1615 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1616 return;
1617
1618 if (qgroup->kobj.state_initialized) {
1619 kobject_del(&qgroup->kobj);
1620 kobject_put(&qgroup->kobj);
1621 }
1622}
1623
1624/*
1625 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
1626 * values in superblock. Call after any changes to incompat/compat_ro flags
1627 */
1628void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
1629 u64 bit, enum btrfs_feature_set set)
1630{
1631 struct btrfs_fs_devices *fs_devs;
1632 struct kobject *fsid_kobj;
1633 u64 features;
1634 int ret;
1635
1636 if (!fs_info)
1637 return;
1638
1639 features = get_features(fs_info, set);
1640 ASSERT(bit & supported_feature_masks[set]);
1641
1642 fs_devs = fs_info->fs_devices;
1643 fsid_kobj = &fs_devs->fsid_kobj;
1644
1645 if (!fsid_kobj->state_initialized)
1646 return;
1647
1648 /*
1649 * FIXME: this is too heavy to update just one value, ideally we'd like
1650 * to use sysfs_update_group but some refactoring is needed first.
1651 */
1652 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1653 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
1654}
1655
1656int __init btrfs_init_sysfs(void)
1657{
1658 int ret;
1659
1660 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
1661 if (!btrfs_kset)
1662 return -ENOMEM;
1663
1664 init_feature_attrs();
1665 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1666 if (ret)
1667 goto out2;
1668 ret = sysfs_merge_group(&btrfs_kset->kobj,
1669 &btrfs_static_feature_attr_group);
1670 if (ret)
1671 goto out_remove_group;
1672
1673#ifdef CONFIG_BTRFS_DEBUG
1674 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1675 if (ret)
1676 goto out2;
1677#endif
1678
1679 return 0;
1680
1681out_remove_group:
1682 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1683out2:
1684 kset_unregister(btrfs_kset);
1685
1686 return ret;
1687}
1688
1689void __cold btrfs_exit_sysfs(void)
1690{
1691 sysfs_unmerge_group(&btrfs_kset->kobj,
1692 &btrfs_static_feature_attr_group);
1693 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1694#ifdef CONFIG_BTRFS_DEBUG
1695 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1696#endif
1697 kset_unregister(btrfs_kset);
1698}
1699