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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/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19#include <linux/sched.h>
20#include <linux/slab.h>
21#include <linux/spinlock.h>
22#include <linux/completion.h>
23#include <linux/buffer_head.h>
24#include <linux/kobject.h>
25#include <linux/bug.h>
26#include <linux/genhd.h>
27#include <linux/debugfs.h>
28
29#include "ctree.h"
30#include "disk-io.h"
31#include "transaction.h"
32#include "sysfs.h"
33#include "volumes.h"
34
35static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
36static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
37
38static u64 get_features(struct btrfs_fs_info *fs_info,
39 enum btrfs_feature_set set)
40{
41 struct btrfs_super_block *disk_super = fs_info->super_copy;
42 if (set == FEAT_COMPAT)
43 return btrfs_super_compat_flags(disk_super);
44 else if (set == FEAT_COMPAT_RO)
45 return btrfs_super_compat_ro_flags(disk_super);
46 else
47 return btrfs_super_incompat_flags(disk_super);
48}
49
50static void set_features(struct btrfs_fs_info *fs_info,
51 enum btrfs_feature_set set, u64 features)
52{
53 struct btrfs_super_block *disk_super = fs_info->super_copy;
54 if (set == FEAT_COMPAT)
55 btrfs_set_super_compat_flags(disk_super, features);
56 else if (set == FEAT_COMPAT_RO)
57 btrfs_set_super_compat_ro_flags(disk_super, features);
58 else
59 btrfs_set_super_incompat_flags(disk_super, features);
60}
61
62static int can_modify_feature(struct btrfs_feature_attr *fa)
63{
64 int val = 0;
65 u64 set, clear;
66 switch (fa->feature_set) {
67 case FEAT_COMPAT:
68 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
69 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
70 break;
71 case FEAT_COMPAT_RO:
72 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
73 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
74 break;
75 case FEAT_INCOMPAT:
76 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
77 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
78 break;
79 default:
80 pr_warn("btrfs: sysfs: unknown feature set %d\n",
81 fa->feature_set);
82 return 0;
83 }
84
85 if (set & fa->feature_bit)
86 val |= 1;
87 if (clear & fa->feature_bit)
88 val |= 2;
89
90 return val;
91}
92
93static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
94 struct kobj_attribute *a, char *buf)
95{
96 int val = 0;
97 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
98 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
99 if (fs_info) {
100 u64 features = get_features(fs_info, fa->feature_set);
101 if (features & fa->feature_bit)
102 val = 1;
103 } else
104 val = can_modify_feature(fa);
105
106 return snprintf(buf, PAGE_SIZE, "%d\n", val);
107}
108
109static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
110 struct kobj_attribute *a,
111 const char *buf, size_t count)
112{
113 struct btrfs_fs_info *fs_info;
114 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
115 u64 features, set, clear;
116 unsigned long val;
117 int ret;
118
119 fs_info = to_fs_info(kobj);
120 if (!fs_info)
121 return -EPERM;
122
123 if (fs_info->sb->s_flags & MS_RDONLY)
124 return -EROFS;
125
126 ret = kstrtoul(skip_spaces(buf), 0, &val);
127 if (ret)
128 return ret;
129
130 if (fa->feature_set == FEAT_COMPAT) {
131 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
132 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
133 } else if (fa->feature_set == FEAT_COMPAT_RO) {
134 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
135 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
136 } else {
137 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
138 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
139 }
140
141 features = get_features(fs_info, fa->feature_set);
142
143 /* Nothing to do */
144 if ((val && (features & fa->feature_bit)) ||
145 (!val && !(features & fa->feature_bit)))
146 return count;
147
148 if ((val && !(set & fa->feature_bit)) ||
149 (!val && !(clear & fa->feature_bit))) {
150 btrfs_info(fs_info,
151 "%sabling feature %s on mounted fs is not supported.",
152 val ? "En" : "Dis", fa->kobj_attr.attr.name);
153 return -EPERM;
154 }
155
156 btrfs_info(fs_info, "%s %s feature flag",
157 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
158
159 spin_lock(&fs_info->super_lock);
160 features = get_features(fs_info, fa->feature_set);
161 if (val)
162 features |= fa->feature_bit;
163 else
164 features &= ~fa->feature_bit;
165 set_features(fs_info, fa->feature_set, features);
166 spin_unlock(&fs_info->super_lock);
167
168 /*
169 * We don't want to do full transaction commit from inside sysfs
170 */
171 btrfs_set_pending(fs_info, COMMIT);
172 wake_up_process(fs_info->transaction_kthread);
173
174 return count;
175}
176
177static umode_t btrfs_feature_visible(struct kobject *kobj,
178 struct attribute *attr, int unused)
179{
180 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
181 umode_t mode = attr->mode;
182
183 if (fs_info) {
184 struct btrfs_feature_attr *fa;
185 u64 features;
186
187 fa = attr_to_btrfs_feature_attr(attr);
188 features = get_features(fs_info, fa->feature_set);
189
190 if (can_modify_feature(fa))
191 mode |= S_IWUSR;
192 else if (!(features & fa->feature_bit))
193 mode = 0;
194 }
195
196 return mode;
197}
198
199BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
200BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
201BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
202BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
203BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
204BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
205BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
206BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
207BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
208BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
209
210static struct attribute *btrfs_supported_feature_attrs[] = {
211 BTRFS_FEAT_ATTR_PTR(mixed_backref),
212 BTRFS_FEAT_ATTR_PTR(default_subvol),
213 BTRFS_FEAT_ATTR_PTR(mixed_groups),
214 BTRFS_FEAT_ATTR_PTR(compress_lzo),
215 BTRFS_FEAT_ATTR_PTR(big_metadata),
216 BTRFS_FEAT_ATTR_PTR(extended_iref),
217 BTRFS_FEAT_ATTR_PTR(raid56),
218 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
219 BTRFS_FEAT_ATTR_PTR(no_holes),
220 BTRFS_FEAT_ATTR_PTR(free_space_tree),
221 NULL
222};
223
224static const struct attribute_group btrfs_feature_attr_group = {
225 .name = "features",
226 .is_visible = btrfs_feature_visible,
227 .attrs = btrfs_supported_feature_attrs,
228};
229
230static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
231{
232 u64 val;
233 if (lock)
234 spin_lock(lock);
235 val = *value_ptr;
236 if (lock)
237 spin_unlock(lock);
238 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
239}
240
241static ssize_t global_rsv_size_show(struct kobject *kobj,
242 struct kobj_attribute *ka, char *buf)
243{
244 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
245 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
246 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
247}
248BTRFS_ATTR(global_rsv_size, global_rsv_size_show);
249
250static ssize_t global_rsv_reserved_show(struct kobject *kobj,
251 struct kobj_attribute *a, char *buf)
252{
253 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
254 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
255 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
256}
257BTRFS_ATTR(global_rsv_reserved, global_rsv_reserved_show);
258
259#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
260#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
261
262static ssize_t raid_bytes_show(struct kobject *kobj,
263 struct kobj_attribute *attr, char *buf);
264BTRFS_RAID_ATTR(total_bytes, raid_bytes_show);
265BTRFS_RAID_ATTR(used_bytes, raid_bytes_show);
266
267static ssize_t raid_bytes_show(struct kobject *kobj,
268 struct kobj_attribute *attr, char *buf)
269
270{
271 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
272 struct btrfs_block_group_cache *block_group;
273 int index = to_raid_kobj(kobj)->raid_type;
274 u64 val = 0;
275
276 down_read(&sinfo->groups_sem);
277 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
278 if (&attr->attr == BTRFS_RAID_ATTR_PTR(total_bytes))
279 val += block_group->key.offset;
280 else
281 val += btrfs_block_group_used(&block_group->item);
282 }
283 up_read(&sinfo->groups_sem);
284 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
285}
286
287static struct attribute *raid_attributes[] = {
288 BTRFS_RAID_ATTR_PTR(total_bytes),
289 BTRFS_RAID_ATTR_PTR(used_bytes),
290 NULL
291};
292
293static void release_raid_kobj(struct kobject *kobj)
294{
295 kfree(to_raid_kobj(kobj));
296}
297
298struct kobj_type btrfs_raid_ktype = {
299 .sysfs_ops = &kobj_sysfs_ops,
300 .release = release_raid_kobj,
301 .default_attrs = raid_attributes,
302};
303
304#define SPACE_INFO_ATTR(field) \
305static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
306 struct kobj_attribute *a, \
307 char *buf) \
308{ \
309 struct btrfs_space_info *sinfo = to_space_info(kobj); \
310 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
311} \
312BTRFS_ATTR(field, btrfs_space_info_show_##field)
313
314static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
315 struct kobj_attribute *a,
316 char *buf)
317{
318 struct btrfs_space_info *sinfo = to_space_info(kobj);
319 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
320 return snprintf(buf, PAGE_SIZE, "%lld\n", val);
321}
322
323SPACE_INFO_ATTR(flags);
324SPACE_INFO_ATTR(total_bytes);
325SPACE_INFO_ATTR(bytes_used);
326SPACE_INFO_ATTR(bytes_pinned);
327SPACE_INFO_ATTR(bytes_reserved);
328SPACE_INFO_ATTR(bytes_may_use);
329SPACE_INFO_ATTR(bytes_readonly);
330SPACE_INFO_ATTR(disk_used);
331SPACE_INFO_ATTR(disk_total);
332BTRFS_ATTR(total_bytes_pinned, btrfs_space_info_show_total_bytes_pinned);
333
334static struct attribute *space_info_attrs[] = {
335 BTRFS_ATTR_PTR(flags),
336 BTRFS_ATTR_PTR(total_bytes),
337 BTRFS_ATTR_PTR(bytes_used),
338 BTRFS_ATTR_PTR(bytes_pinned),
339 BTRFS_ATTR_PTR(bytes_reserved),
340 BTRFS_ATTR_PTR(bytes_may_use),
341 BTRFS_ATTR_PTR(bytes_readonly),
342 BTRFS_ATTR_PTR(disk_used),
343 BTRFS_ATTR_PTR(disk_total),
344 BTRFS_ATTR_PTR(total_bytes_pinned),
345 NULL,
346};
347
348static void space_info_release(struct kobject *kobj)
349{
350 struct btrfs_space_info *sinfo = to_space_info(kobj);
351 percpu_counter_destroy(&sinfo->total_bytes_pinned);
352 kfree(sinfo);
353}
354
355struct kobj_type space_info_ktype = {
356 .sysfs_ops = &kobj_sysfs_ops,
357 .release = space_info_release,
358 .default_attrs = space_info_attrs,
359};
360
361static const struct attribute *allocation_attrs[] = {
362 BTRFS_ATTR_PTR(global_rsv_reserved),
363 BTRFS_ATTR_PTR(global_rsv_size),
364 NULL,
365};
366
367static ssize_t btrfs_label_show(struct kobject *kobj,
368 struct kobj_attribute *a, char *buf)
369{
370 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
371 char *label = fs_info->super_copy->label;
372 ssize_t ret;
373
374 spin_lock(&fs_info->super_lock);
375 ret = snprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
376 spin_unlock(&fs_info->super_lock);
377
378 return ret;
379}
380
381static ssize_t btrfs_label_store(struct kobject *kobj,
382 struct kobj_attribute *a,
383 const char *buf, size_t len)
384{
385 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
386 size_t p_len;
387
388 if (!fs_info)
389 return -EPERM;
390
391 if (fs_info->sb->s_flags & MS_RDONLY)
392 return -EROFS;
393
394 /*
395 * p_len is the len until the first occurrence of either
396 * '\n' or '\0'
397 */
398 p_len = strcspn(buf, "\n");
399
400 if (p_len >= BTRFS_LABEL_SIZE)
401 return -EINVAL;
402
403 spin_lock(&fs_info->super_lock);
404 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
405 memcpy(fs_info->super_copy->label, buf, p_len);
406 spin_unlock(&fs_info->super_lock);
407
408 /*
409 * We don't want to do full transaction commit from inside sysfs
410 */
411 btrfs_set_pending(fs_info, COMMIT);
412 wake_up_process(fs_info->transaction_kthread);
413
414 return len;
415}
416BTRFS_ATTR_RW(label, btrfs_label_show, btrfs_label_store);
417
418static ssize_t btrfs_nodesize_show(struct kobject *kobj,
419 struct kobj_attribute *a, char *buf)
420{
421 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
422
423 return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
424}
425
426BTRFS_ATTR(nodesize, btrfs_nodesize_show);
427
428static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
429 struct kobj_attribute *a, char *buf)
430{
431 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
432
433 return snprintf(buf, PAGE_SIZE, "%u\n",
434 fs_info->super_copy->sectorsize);
435}
436
437BTRFS_ATTR(sectorsize, btrfs_sectorsize_show);
438
439static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
440 struct kobj_attribute *a, char *buf)
441{
442 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
443
444 return snprintf(buf, PAGE_SIZE, "%u\n",
445 fs_info->super_copy->sectorsize);
446}
447
448BTRFS_ATTR(clone_alignment, btrfs_clone_alignment_show);
449
450static const struct attribute *btrfs_attrs[] = {
451 BTRFS_ATTR_PTR(label),
452 BTRFS_ATTR_PTR(nodesize),
453 BTRFS_ATTR_PTR(sectorsize),
454 BTRFS_ATTR_PTR(clone_alignment),
455 NULL,
456};
457
458static void btrfs_release_fsid_kobj(struct kobject *kobj)
459{
460 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
461
462 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
463 complete(&fs_devs->kobj_unregister);
464}
465
466static struct kobj_type btrfs_ktype = {
467 .sysfs_ops = &kobj_sysfs_ops,
468 .release = btrfs_release_fsid_kobj,
469};
470
471static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
472{
473 if (kobj->ktype != &btrfs_ktype)
474 return NULL;
475 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
476}
477
478static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
479{
480 if (kobj->ktype != &btrfs_ktype)
481 return NULL;
482 return to_fs_devs(kobj)->fs_info;
483}
484
485#define NUM_FEATURE_BITS 64
486static char btrfs_unknown_feature_names[3][NUM_FEATURE_BITS][13];
487static struct btrfs_feature_attr btrfs_feature_attrs[3][NUM_FEATURE_BITS];
488
489static const u64 supported_feature_masks[3] = {
490 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
491 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
492 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
493};
494
495static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
496{
497 int set;
498
499 for (set = 0; set < FEAT_MAX; set++) {
500 int i;
501 struct attribute *attrs[2];
502 struct attribute_group agroup = {
503 .name = "features",
504 .attrs = attrs,
505 };
506 u64 features = get_features(fs_info, set);
507 features &= ~supported_feature_masks[set];
508
509 if (!features)
510 continue;
511
512 attrs[1] = NULL;
513 for (i = 0; i < NUM_FEATURE_BITS; i++) {
514 struct btrfs_feature_attr *fa;
515
516 if (!(features & (1ULL << i)))
517 continue;
518
519 fa = &btrfs_feature_attrs[set][i];
520 attrs[0] = &fa->kobj_attr.attr;
521 if (add) {
522 int ret;
523 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
524 &agroup);
525 if (ret)
526 return ret;
527 } else
528 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
529 &agroup);
530 }
531
532 }
533 return 0;
534}
535
536static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
537{
538 if (fs_devs->device_dir_kobj) {
539 kobject_del(fs_devs->device_dir_kobj);
540 kobject_put(fs_devs->device_dir_kobj);
541 fs_devs->device_dir_kobj = NULL;
542 }
543
544 if (fs_devs->fsid_kobj.state_initialized) {
545 kobject_del(&fs_devs->fsid_kobj);
546 kobject_put(&fs_devs->fsid_kobj);
547 wait_for_completion(&fs_devs->kobj_unregister);
548 }
549}
550
551/* when fs_devs is NULL it will remove all fsid kobject */
552void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
553{
554 struct list_head *fs_uuids = btrfs_get_fs_uuids();
555
556 if (fs_devs) {
557 __btrfs_sysfs_remove_fsid(fs_devs);
558 return;
559 }
560
561 list_for_each_entry(fs_devs, fs_uuids, list) {
562 __btrfs_sysfs_remove_fsid(fs_devs);
563 }
564}
565
566void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
567{
568 btrfs_reset_fs_info_ptr(fs_info);
569
570 if (fs_info->space_info_kobj) {
571 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
572 kobject_del(fs_info->space_info_kobj);
573 kobject_put(fs_info->space_info_kobj);
574 }
575 addrm_unknown_feature_attrs(fs_info, false);
576 sysfs_remove_group(&fs_info->fs_devices->fsid_kobj, &btrfs_feature_attr_group);
577 sysfs_remove_files(&fs_info->fs_devices->fsid_kobj, btrfs_attrs);
578 btrfs_sysfs_rm_device_link(fs_info->fs_devices, NULL);
579}
580
581const char * const btrfs_feature_set_names[3] = {
582 [FEAT_COMPAT] = "compat",
583 [FEAT_COMPAT_RO] = "compat_ro",
584 [FEAT_INCOMPAT] = "incompat",
585};
586
587char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
588{
589 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
590 int len = 0;
591 int i;
592 char *str;
593
594 str = kmalloc(bufsize, GFP_KERNEL);
595 if (!str)
596 return str;
597
598 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
599 const char *name;
600
601 if (!(flags & (1ULL << i)))
602 continue;
603
604 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
605 len += snprintf(str + len, bufsize - len, "%s%s",
606 len ? "," : "", name);
607 }
608
609 return str;
610}
611
612static void init_feature_attrs(void)
613{
614 struct btrfs_feature_attr *fa;
615 int set, i;
616
617 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
618 ARRAY_SIZE(btrfs_feature_attrs));
619 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
620 ARRAY_SIZE(btrfs_feature_attrs[0]));
621
622 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
623 memset(btrfs_unknown_feature_names, 0,
624 sizeof(btrfs_unknown_feature_names));
625
626 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
627 struct btrfs_feature_attr *sfa;
628 struct attribute *a = btrfs_supported_feature_attrs[i];
629 int bit;
630 sfa = attr_to_btrfs_feature_attr(a);
631 bit = ilog2(sfa->feature_bit);
632 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
633
634 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
635 }
636
637 for (set = 0; set < FEAT_MAX; set++) {
638 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
639 char *name = btrfs_unknown_feature_names[set][i];
640 fa = &btrfs_feature_attrs[set][i];
641
642 if (fa->kobj_attr.attr.name)
643 continue;
644
645 snprintf(name, 13, "%s:%u",
646 btrfs_feature_set_names[set], i);
647
648 fa->kobj_attr.attr.name = name;
649 fa->kobj_attr.attr.mode = S_IRUGO;
650 fa->feature_set = set;
651 fa->feature_bit = 1ULL << i;
652 }
653 }
654}
655
656/* when one_device is NULL, it removes all device links */
657
658int btrfs_sysfs_rm_device_link(struct btrfs_fs_devices *fs_devices,
659 struct btrfs_device *one_device)
660{
661 struct hd_struct *disk;
662 struct kobject *disk_kobj;
663
664 if (!fs_devices->device_dir_kobj)
665 return -EINVAL;
666
667 if (one_device && one_device->bdev) {
668 disk = one_device->bdev->bd_part;
669 disk_kobj = &part_to_dev(disk)->kobj;
670
671 sysfs_remove_link(fs_devices->device_dir_kobj,
672 disk_kobj->name);
673 }
674
675 if (one_device)
676 return 0;
677
678 list_for_each_entry(one_device,
679 &fs_devices->devices, dev_list) {
680 if (!one_device->bdev)
681 continue;
682 disk = one_device->bdev->bd_part;
683 disk_kobj = &part_to_dev(disk)->kobj;
684
685 sysfs_remove_link(fs_devices->device_dir_kobj,
686 disk_kobj->name);
687 }
688
689 return 0;
690}
691
692int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs)
693{
694 if (!fs_devs->device_dir_kobj)
695 fs_devs->device_dir_kobj = kobject_create_and_add("devices",
696 &fs_devs->fsid_kobj);
697
698 if (!fs_devs->device_dir_kobj)
699 return -ENOMEM;
700
701 return 0;
702}
703
704int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices,
705 struct btrfs_device *one_device)
706{
707 int error = 0;
708 struct btrfs_device *dev;
709
710 list_for_each_entry(dev, &fs_devices->devices, dev_list) {
711 struct hd_struct *disk;
712 struct kobject *disk_kobj;
713
714 if (!dev->bdev)
715 continue;
716
717 if (one_device && one_device != dev)
718 continue;
719
720 disk = dev->bdev->bd_part;
721 disk_kobj = &part_to_dev(disk)->kobj;
722
723 error = sysfs_create_link(fs_devices->device_dir_kobj,
724 disk_kobj, disk_kobj->name);
725 if (error)
726 break;
727 }
728
729 return error;
730}
731
732/* /sys/fs/btrfs/ entry */
733static struct kset *btrfs_kset;
734
735/* /sys/kernel/debug/btrfs */
736static struct dentry *btrfs_debugfs_root_dentry;
737
738/* Debugging tunables and exported data */
739u64 btrfs_debugfs_test;
740
741/*
742 * Can be called by the device discovery thread.
743 * And parent can be specified for seed device
744 */
745int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs,
746 struct kobject *parent)
747{
748 int error;
749
750 init_completion(&fs_devs->kobj_unregister);
751 fs_devs->fsid_kobj.kset = btrfs_kset;
752 error = kobject_init_and_add(&fs_devs->fsid_kobj,
753 &btrfs_ktype, parent, "%pU", fs_devs->fsid);
754 return error;
755}
756
757int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
758{
759 int error;
760 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
761 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
762
763 btrfs_set_fs_info_ptr(fs_info);
764
765 error = btrfs_sysfs_add_device_link(fs_devs, NULL);
766 if (error)
767 return error;
768
769 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
770 if (error) {
771 btrfs_sysfs_rm_device_link(fs_devs, NULL);
772 return error;
773 }
774
775 error = sysfs_create_group(fsid_kobj,
776 &btrfs_feature_attr_group);
777 if (error)
778 goto failure;
779
780 error = addrm_unknown_feature_attrs(fs_info, true);
781 if (error)
782 goto failure;
783
784 fs_info->space_info_kobj = kobject_create_and_add("allocation",
785 fsid_kobj);
786 if (!fs_info->space_info_kobj) {
787 error = -ENOMEM;
788 goto failure;
789 }
790
791 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
792 if (error)
793 goto failure;
794
795 return 0;
796failure:
797 btrfs_sysfs_remove_mounted(fs_info);
798 return error;
799}
800
801
802/*
803 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
804 * values in superblock. Call after any changes to incompat/compat_ro flags
805 */
806void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
807 u64 bit, enum btrfs_feature_set set)
808{
809 struct btrfs_fs_devices *fs_devs;
810 struct kobject *fsid_kobj;
811 u64 features;
812 int ret;
813
814 if (!fs_info)
815 return;
816
817 features = get_features(fs_info, set);
818 ASSERT(bit & supported_feature_masks[set]);
819
820 fs_devs = fs_info->fs_devices;
821 fsid_kobj = &fs_devs->fsid_kobj;
822
823 if (!fsid_kobj->state_initialized)
824 return;
825
826 /*
827 * FIXME: this is too heavy to update just one value, ideally we'd like
828 * to use sysfs_update_group but some refactoring is needed first.
829 */
830 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
831 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
832}
833
834static int btrfs_init_debugfs(void)
835{
836#ifdef CONFIG_DEBUG_FS
837 btrfs_debugfs_root_dentry = debugfs_create_dir("btrfs", NULL);
838 if (!btrfs_debugfs_root_dentry)
839 return -ENOMEM;
840
841 /*
842 * Example code, how to export data through debugfs.
843 *
844 * file: /sys/kernel/debug/btrfs/test
845 * contents of: btrfs_debugfs_test
846 */
847#ifdef CONFIG_BTRFS_DEBUG
848 debugfs_create_u64("test", S_IRUGO | S_IWUSR, btrfs_debugfs_root_dentry,
849 &btrfs_debugfs_test);
850#endif
851
852#endif
853 return 0;
854}
855
856int btrfs_init_sysfs(void)
857{
858 int ret;
859
860 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
861 if (!btrfs_kset)
862 return -ENOMEM;
863
864 ret = btrfs_init_debugfs();
865 if (ret)
866 goto out1;
867
868 init_feature_attrs();
869 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
870 if (ret)
871 goto out2;
872
873 return 0;
874out2:
875 debugfs_remove_recursive(btrfs_debugfs_root_dentry);
876out1:
877 kset_unregister(btrfs_kset);
878
879 return ret;
880}
881
882void btrfs_exit_sysfs(void)
883{
884 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
885 kset_unregister(btrfs_kset);
886 debugfs_remove_recursive(btrfs_debugfs_root_dentry);
887}
888