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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/module.h>
25#include <linux/kobject.h>
26
27#include "ctree.h"
28#include "disk-io.h"
29#include "transaction.h"
30
31/* /sys/fs/btrfs/ entry */
32static struct kset *btrfs_kset;
33
34int btrfs_init_sysfs(void)
35{
36 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
37 if (!btrfs_kset)
38 return -ENOMEM;
39 return 0;
40}
41
42void btrfs_exit_sysfs(void)
43{
44 kset_unregister(btrfs_kset);
45}
46
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#include <linux/sched.h>
7#include <linux/sched/mm.h>
8#include <linux/slab.h>
9#include <linux/spinlock.h>
10#include <linux/completion.h>
11#include <linux/bug.h>
12#include <linux/list.h>
13#include <crypto/hash.h>
14#include "messages.h"
15#include "ctree.h"
16#include "discard.h"
17#include "disk-io.h"
18#include "send.h"
19#include "transaction.h"
20#include "sysfs.h"
21#include "volumes.h"
22#include "space-info.h"
23#include "block-group.h"
24#include "qgroup.h"
25#include "misc.h"
26#include "fs.h"
27#include "accessors.h"
28
29/*
30 * Structure name Path
31 * --------------------------------------------------------------------------
32 * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features
33 * btrfs_supported_feature_attrs /sys/fs/btrfs/features and
34 * /sys/fs/btrfs/<uuid>/features
35 * btrfs_attrs /sys/fs/btrfs/<uuid>
36 * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid>
37 * allocation_attrs /sys/fs/btrfs/<uuid>/allocation
38 * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>
39 * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>
40 * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>
41 * discard_attrs /sys/fs/btrfs/<uuid>/discard
42 *
43 * When built with BTRFS_CONFIG_DEBUG:
44 *
45 * btrfs_debug_feature_attrs /sys/fs/btrfs/debug
46 * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug
47 */
48
49struct btrfs_feature_attr {
50 struct kobj_attribute kobj_attr;
51 enum btrfs_feature_set feature_set;
52 u64 feature_bit;
53};
54
55/* For raid type sysfs entries */
56struct raid_kobject {
57 u64 flags;
58 struct kobject kobj;
59};
60
61#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
62{ \
63 .attr = { .name = __stringify(_name), .mode = _mode }, \
64 .show = _show, \
65 .store = _store, \
66}
67
68#define BTRFS_ATTR_W(_prefix, _name, _store) \
69 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
70 __INIT_KOBJ_ATTR(_name, 0200, NULL, _store)
71
72#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
73 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
74 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
75
76#define BTRFS_ATTR(_prefix, _name, _show) \
77 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
78 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
79
80#define BTRFS_ATTR_PTR(_prefix, _name) \
81 (&btrfs_attr_##_prefix##_##_name.attr)
82
83#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
84static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
85 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
86 btrfs_feature_attr_show, \
87 btrfs_feature_attr_store), \
88 .feature_set = _feature_set, \
89 .feature_bit = _feature_prefix ##_## _feature_bit, \
90}
91#define BTRFS_FEAT_ATTR_PTR(_name) \
92 (&btrfs_attr_features_##_name.kobj_attr.attr)
93
94#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
95 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
96#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
97 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
98#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
99 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
100
101static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
102static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
103static struct kobject *get_btrfs_kobj(struct kobject *kobj);
104
105static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
106{
107 return container_of(a, struct btrfs_feature_attr, kobj_attr);
108}
109
110static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
111{
112 return container_of(attr, struct kobj_attribute, attr);
113}
114
115static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
116 struct attribute *attr)
117{
118 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
119}
120
121static u64 get_features(struct btrfs_fs_info *fs_info,
122 enum btrfs_feature_set set)
123{
124 struct btrfs_super_block *disk_super = fs_info->super_copy;
125 if (set == FEAT_COMPAT)
126 return btrfs_super_compat_flags(disk_super);
127 else if (set == FEAT_COMPAT_RO)
128 return btrfs_super_compat_ro_flags(disk_super);
129 else
130 return btrfs_super_incompat_flags(disk_super);
131}
132
133static void set_features(struct btrfs_fs_info *fs_info,
134 enum btrfs_feature_set set, u64 features)
135{
136 struct btrfs_super_block *disk_super = fs_info->super_copy;
137 if (set == FEAT_COMPAT)
138 btrfs_set_super_compat_flags(disk_super, features);
139 else if (set == FEAT_COMPAT_RO)
140 btrfs_set_super_compat_ro_flags(disk_super, features);
141 else
142 btrfs_set_super_incompat_flags(disk_super, features);
143}
144
145static int can_modify_feature(struct btrfs_feature_attr *fa)
146{
147 int val = 0;
148 u64 set, clear;
149 switch (fa->feature_set) {
150 case FEAT_COMPAT:
151 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
152 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
153 break;
154 case FEAT_COMPAT_RO:
155 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
156 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
157 break;
158 case FEAT_INCOMPAT:
159 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
160 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
161 break;
162 default:
163 pr_warn("btrfs: sysfs: unknown feature set %d\n",
164 fa->feature_set);
165 return 0;
166 }
167
168 if (set & fa->feature_bit)
169 val |= 1;
170 if (clear & fa->feature_bit)
171 val |= 2;
172
173 return val;
174}
175
176static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
177 struct kobj_attribute *a, char *buf)
178{
179 int val = 0;
180 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
181 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
182 if (fs_info) {
183 u64 features = get_features(fs_info, fa->feature_set);
184 if (features & fa->feature_bit)
185 val = 1;
186 } else
187 val = can_modify_feature(fa);
188
189 return sysfs_emit(buf, "%d\n", val);
190}
191
192static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
193 struct kobj_attribute *a,
194 const char *buf, size_t count)
195{
196 struct btrfs_fs_info *fs_info;
197 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
198 u64 features, set, clear;
199 unsigned long val;
200 int ret;
201
202 fs_info = to_fs_info(kobj);
203 if (!fs_info)
204 return -EPERM;
205
206 if (sb_rdonly(fs_info->sb))
207 return -EROFS;
208
209 ret = kstrtoul(skip_spaces(buf), 0, &val);
210 if (ret)
211 return ret;
212
213 if (fa->feature_set == FEAT_COMPAT) {
214 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
215 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
216 } else if (fa->feature_set == FEAT_COMPAT_RO) {
217 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
218 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
219 } else {
220 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
221 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
222 }
223
224 features = get_features(fs_info, fa->feature_set);
225
226 /* Nothing to do */
227 if ((val && (features & fa->feature_bit)) ||
228 (!val && !(features & fa->feature_bit)))
229 return count;
230
231 if ((val && !(set & fa->feature_bit)) ||
232 (!val && !(clear & fa->feature_bit))) {
233 btrfs_info(fs_info,
234 "%sabling feature %s on mounted fs is not supported.",
235 val ? "En" : "Dis", fa->kobj_attr.attr.name);
236 return -EPERM;
237 }
238
239 btrfs_info(fs_info, "%s %s feature flag",
240 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
241
242 spin_lock(&fs_info->super_lock);
243 features = get_features(fs_info, fa->feature_set);
244 if (val)
245 features |= fa->feature_bit;
246 else
247 features &= ~fa->feature_bit;
248 set_features(fs_info, fa->feature_set, features);
249 spin_unlock(&fs_info->super_lock);
250
251 /*
252 * We don't want to do full transaction commit from inside sysfs
253 */
254 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
255 wake_up_process(fs_info->transaction_kthread);
256
257 return count;
258}
259
260static umode_t btrfs_feature_visible(struct kobject *kobj,
261 struct attribute *attr, int unused)
262{
263 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
264 umode_t mode = attr->mode;
265
266 if (fs_info) {
267 struct btrfs_feature_attr *fa;
268 u64 features;
269
270 fa = attr_to_btrfs_feature_attr(attr);
271 features = get_features(fs_info, fa->feature_set);
272
273 if (can_modify_feature(fa))
274 mode |= S_IWUSR;
275 else if (!(features & fa->feature_bit))
276 mode = 0;
277 }
278
279 return mode;
280}
281
282BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
283BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
284BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
285BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
286BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
287BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
288BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
289BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
290BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
291BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
292BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE);
293BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
294BTRFS_FEAT_ATTR_INCOMPAT(simple_quota, SIMPLE_QUOTA);
295#ifdef CONFIG_BLK_DEV_ZONED
296BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
297#endif
298#ifdef CONFIG_BTRFS_DEBUG
299/* Remove once support for extent tree v2 is feature complete */
300BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2);
301/* Remove once support for raid stripe tree is feature complete. */
302BTRFS_FEAT_ATTR_INCOMPAT(raid_stripe_tree, RAID_STRIPE_TREE);
303#endif
304#ifdef CONFIG_FS_VERITY
305BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
306#endif
307
308/*
309 * Features which depend on feature bits and may differ between each fs.
310 *
311 * /sys/fs/btrfs/features - all available features implemented by this version
312 * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or
313 * can be changed on a mounted filesystem.
314 */
315static struct attribute *btrfs_supported_feature_attrs[] = {
316 BTRFS_FEAT_ATTR_PTR(default_subvol),
317 BTRFS_FEAT_ATTR_PTR(mixed_groups),
318 BTRFS_FEAT_ATTR_PTR(compress_lzo),
319 BTRFS_FEAT_ATTR_PTR(compress_zstd),
320 BTRFS_FEAT_ATTR_PTR(extended_iref),
321 BTRFS_FEAT_ATTR_PTR(raid56),
322 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
323 BTRFS_FEAT_ATTR_PTR(no_holes),
324 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
325 BTRFS_FEAT_ATTR_PTR(free_space_tree),
326 BTRFS_FEAT_ATTR_PTR(raid1c34),
327 BTRFS_FEAT_ATTR_PTR(block_group_tree),
328 BTRFS_FEAT_ATTR_PTR(simple_quota),
329#ifdef CONFIG_BLK_DEV_ZONED
330 BTRFS_FEAT_ATTR_PTR(zoned),
331#endif
332#ifdef CONFIG_BTRFS_DEBUG
333 BTRFS_FEAT_ATTR_PTR(extent_tree_v2),
334 BTRFS_FEAT_ATTR_PTR(raid_stripe_tree),
335#endif
336#ifdef CONFIG_FS_VERITY
337 BTRFS_FEAT_ATTR_PTR(verity),
338#endif
339 NULL
340};
341
342static const struct attribute_group btrfs_feature_attr_group = {
343 .name = "features",
344 .is_visible = btrfs_feature_visible,
345 .attrs = btrfs_supported_feature_attrs,
346};
347
348static ssize_t rmdir_subvol_show(struct kobject *kobj,
349 struct kobj_attribute *ka, char *buf)
350{
351 return sysfs_emit(buf, "0\n");
352}
353BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
354
355static ssize_t supported_checksums_show(struct kobject *kobj,
356 struct kobj_attribute *a, char *buf)
357{
358 ssize_t ret = 0;
359 int i;
360
361 for (i = 0; i < btrfs_get_num_csums(); i++) {
362 /*
363 * This "trick" only works as long as 'enum btrfs_csum_type' has
364 * no holes in it
365 */
366 ret += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "),
367 btrfs_super_csum_name(i));
368
369 }
370
371 ret += sysfs_emit_at(buf, ret, "\n");
372 return ret;
373}
374BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
375
376static ssize_t send_stream_version_show(struct kobject *kobj,
377 struct kobj_attribute *ka, char *buf)
378{
379 return sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION);
380}
381BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
382
383static const char *rescue_opts[] = {
384 "usebackuproot",
385 "nologreplay",
386 "ignorebadroots",
387 "ignoredatacsums",
388 "all",
389};
390
391static ssize_t supported_rescue_options_show(struct kobject *kobj,
392 struct kobj_attribute *a,
393 char *buf)
394{
395 ssize_t ret = 0;
396 int i;
397
398 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
399 ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]);
400 ret += sysfs_emit_at(buf, ret, "\n");
401 return ret;
402}
403BTRFS_ATTR(static_feature, supported_rescue_options,
404 supported_rescue_options_show);
405
406static ssize_t supported_sectorsizes_show(struct kobject *kobj,
407 struct kobj_attribute *a,
408 char *buf)
409{
410 ssize_t ret = 0;
411
412 /* An artificial limit to only support 4K and PAGE_SIZE */
413 if (PAGE_SIZE > SZ_4K)
414 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K);
415 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE);
416
417 return ret;
418}
419BTRFS_ATTR(static_feature, supported_sectorsizes,
420 supported_sectorsizes_show);
421
422static ssize_t acl_show(struct kobject *kobj, struct kobj_attribute *a, char *buf)
423{
424 return sysfs_emit(buf, "%d\n", IS_ENABLED(CONFIG_BTRFS_FS_POSIX_ACL));
425}
426BTRFS_ATTR(static_feature, acl, acl_show);
427
428static ssize_t temp_fsid_supported_show(struct kobject *kobj,
429 struct kobj_attribute *a, char *buf)
430{
431 return sysfs_emit(buf, "0\n");
432}
433BTRFS_ATTR(static_feature, temp_fsid, temp_fsid_supported_show);
434
435/*
436 * Features which only depend on kernel version.
437 *
438 * These are listed in /sys/fs/btrfs/features along with
439 * btrfs_supported_feature_attrs.
440 */
441static struct attribute *btrfs_supported_static_feature_attrs[] = {
442 BTRFS_ATTR_PTR(static_feature, acl),
443 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
444 BTRFS_ATTR_PTR(static_feature, supported_checksums),
445 BTRFS_ATTR_PTR(static_feature, send_stream_version),
446 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
447 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
448 BTRFS_ATTR_PTR(static_feature, temp_fsid),
449 NULL
450};
451
452static const struct attribute_group btrfs_static_feature_attr_group = {
453 .name = "features",
454 .attrs = btrfs_supported_static_feature_attrs,
455};
456
457/*
458 * Discard statistics and tunables
459 */
460#define discard_to_fs_info(_kobj) to_fs_info(get_btrfs_kobj(_kobj))
461
462static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
463 struct kobj_attribute *a,
464 char *buf)
465{
466 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
467
468 return sysfs_emit(buf, "%lld\n",
469 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
470}
471BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
472
473static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
474 struct kobj_attribute *a,
475 char *buf)
476{
477 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
478
479 return sysfs_emit(buf, "%d\n",
480 atomic_read(&fs_info->discard_ctl.discardable_extents));
481}
482BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
483
484static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
485 struct kobj_attribute *a,
486 char *buf)
487{
488 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
489
490 return sysfs_emit(buf, "%llu\n",
491 fs_info->discard_ctl.discard_bitmap_bytes);
492}
493BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
494
495static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
496 struct kobj_attribute *a,
497 char *buf)
498{
499 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
500
501 return sysfs_emit(buf, "%lld\n",
502 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
503}
504BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
505
506static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
507 struct kobj_attribute *a,
508 char *buf)
509{
510 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
511
512 return sysfs_emit(buf, "%llu\n",
513 fs_info->discard_ctl.discard_extent_bytes);
514}
515BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
516
517static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
518 struct kobj_attribute *a,
519 char *buf)
520{
521 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
522
523 return sysfs_emit(buf, "%u\n",
524 READ_ONCE(fs_info->discard_ctl.iops_limit));
525}
526
527static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
528 struct kobj_attribute *a,
529 const char *buf, size_t len)
530{
531 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
532 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
533 u32 iops_limit;
534 int ret;
535
536 ret = kstrtou32(buf, 10, &iops_limit);
537 if (ret)
538 return -EINVAL;
539
540 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
541 btrfs_discard_calc_delay(discard_ctl);
542 btrfs_discard_schedule_work(discard_ctl, true);
543 return len;
544}
545BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
546 btrfs_discard_iops_limit_store);
547
548static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
549 struct kobj_attribute *a,
550 char *buf)
551{
552 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
553
554 return sysfs_emit(buf, "%u\n",
555 READ_ONCE(fs_info->discard_ctl.kbps_limit));
556}
557
558static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
559 struct kobj_attribute *a,
560 const char *buf, size_t len)
561{
562 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
563 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
564 u32 kbps_limit;
565 int ret;
566
567 ret = kstrtou32(buf, 10, &kbps_limit);
568 if (ret)
569 return -EINVAL;
570
571 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
572 btrfs_discard_schedule_work(discard_ctl, true);
573 return len;
574}
575BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
576 btrfs_discard_kbps_limit_store);
577
578static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
579 struct kobj_attribute *a,
580 char *buf)
581{
582 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
583
584 return sysfs_emit(buf, "%llu\n",
585 READ_ONCE(fs_info->discard_ctl.max_discard_size));
586}
587
588static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
589 struct kobj_attribute *a,
590 const char *buf, size_t len)
591{
592 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
593 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
594 u64 max_discard_size;
595 int ret;
596
597 ret = kstrtou64(buf, 10, &max_discard_size);
598 if (ret)
599 return -EINVAL;
600
601 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
602
603 return len;
604}
605BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
606 btrfs_discard_max_discard_size_store);
607
608/*
609 * Per-filesystem stats for discard (when mounted with discard=async).
610 *
611 * Path: /sys/fs/btrfs/<uuid>/discard/
612 */
613static const struct attribute *discard_attrs[] = {
614 BTRFS_ATTR_PTR(discard, discardable_bytes),
615 BTRFS_ATTR_PTR(discard, discardable_extents),
616 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
617 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
618 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
619 BTRFS_ATTR_PTR(discard, iops_limit),
620 BTRFS_ATTR_PTR(discard, kbps_limit),
621 BTRFS_ATTR_PTR(discard, max_discard_size),
622 NULL,
623};
624
625#ifdef CONFIG_BTRFS_DEBUG
626
627/*
628 * Per-filesystem runtime debugging exported via sysfs.
629 *
630 * Path: /sys/fs/btrfs/UUID/debug/
631 */
632static const struct attribute *btrfs_debug_mount_attrs[] = {
633 NULL,
634};
635
636/*
637 * Runtime debugging exported via sysfs, applies to all mounted filesystems.
638 *
639 * Path: /sys/fs/btrfs/debug
640 */
641static struct attribute *btrfs_debug_feature_attrs[] = {
642 NULL
643};
644
645static const struct attribute_group btrfs_debug_feature_attr_group = {
646 .name = "debug",
647 .attrs = btrfs_debug_feature_attrs,
648};
649
650#endif
651
652static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
653{
654 u64 val;
655 if (lock)
656 spin_lock(lock);
657 val = *value_ptr;
658 if (lock)
659 spin_unlock(lock);
660 return sysfs_emit(buf, "%llu\n", val);
661}
662
663static ssize_t global_rsv_size_show(struct kobject *kobj,
664 struct kobj_attribute *ka, char *buf)
665{
666 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
667 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
668 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
669}
670BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
671
672static ssize_t global_rsv_reserved_show(struct kobject *kobj,
673 struct kobj_attribute *a, char *buf)
674{
675 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
676 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
677 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
678}
679BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
680
681#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
682#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
683
684static ssize_t raid_bytes_show(struct kobject *kobj,
685 struct kobj_attribute *attr, char *buf);
686BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
687BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
688
689static ssize_t raid_bytes_show(struct kobject *kobj,
690 struct kobj_attribute *attr, char *buf)
691
692{
693 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
694 struct btrfs_block_group *block_group;
695 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
696 u64 val = 0;
697
698 down_read(&sinfo->groups_sem);
699 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
700 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
701 val += block_group->length;
702 else
703 val += block_group->used;
704 }
705 up_read(&sinfo->groups_sem);
706 return sysfs_emit(buf, "%llu\n", val);
707}
708
709/*
710 * Allocation information about block group profiles.
711 *
712 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/
713 */
714static struct attribute *raid_attrs[] = {
715 BTRFS_ATTR_PTR(raid, total_bytes),
716 BTRFS_ATTR_PTR(raid, used_bytes),
717 NULL
718};
719ATTRIBUTE_GROUPS(raid);
720
721static void release_raid_kobj(struct kobject *kobj)
722{
723 kfree(to_raid_kobj(kobj));
724}
725
726static const struct kobj_type btrfs_raid_ktype = {
727 .sysfs_ops = &kobj_sysfs_ops,
728 .release = release_raid_kobj,
729 .default_groups = raid_groups,
730};
731
732#define SPACE_INFO_ATTR(field) \
733static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
734 struct kobj_attribute *a, \
735 char *buf) \
736{ \
737 struct btrfs_space_info *sinfo = to_space_info(kobj); \
738 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
739} \
740BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
741
742static ssize_t btrfs_chunk_size_show(struct kobject *kobj,
743 struct kobj_attribute *a, char *buf)
744{
745 struct btrfs_space_info *sinfo = to_space_info(kobj);
746
747 return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size));
748}
749
750/*
751 * Store new chunk size in space info. Can be called on a read-only filesystem.
752 *
753 * If the new chunk size value is larger than 10% of free space it is reduced
754 * to match that limit. Alignment must be to 256M and the system chunk size
755 * cannot be set.
756 */
757static ssize_t btrfs_chunk_size_store(struct kobject *kobj,
758 struct kobj_attribute *a,
759 const char *buf, size_t len)
760{
761 struct btrfs_space_info *space_info = to_space_info(kobj);
762 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
763 char *retptr;
764 u64 val;
765
766 if (!capable(CAP_SYS_ADMIN))
767 return -EPERM;
768
769 if (!fs_info->fs_devices)
770 return -EINVAL;
771
772 if (btrfs_is_zoned(fs_info))
773 return -EINVAL;
774
775 /* System block type must not be changed. */
776 if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
777 return -EPERM;
778
779 val = memparse(buf, &retptr);
780 /* There could be trailing '\n', also catch any typos after the value */
781 retptr = skip_spaces(retptr);
782 if (*retptr != 0 || val == 0)
783 return -EINVAL;
784
785 val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE);
786
787 /* Limit stripe size to 10% of available space. */
788 val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val);
789
790 /* Must be multiple of 256M. */
791 val &= ~((u64)SZ_256M - 1);
792
793 /* Must be at least 256M. */
794 if (val < SZ_256M)
795 return -EINVAL;
796
797 btrfs_update_space_info_chunk_size(space_info, val);
798
799 return len;
800}
801
802static ssize_t btrfs_size_classes_show(struct kobject *kobj,
803 struct kobj_attribute *a, char *buf)
804{
805 struct btrfs_space_info *sinfo = to_space_info(kobj);
806 struct btrfs_block_group *bg;
807 u32 none = 0;
808 u32 small = 0;
809 u32 medium = 0;
810 u32 large = 0;
811
812 for (int i = 0; i < BTRFS_NR_RAID_TYPES; ++i) {
813 down_read(&sinfo->groups_sem);
814 list_for_each_entry(bg, &sinfo->block_groups[i], list) {
815 if (!btrfs_block_group_should_use_size_class(bg))
816 continue;
817 switch (bg->size_class) {
818 case BTRFS_BG_SZ_NONE:
819 none++;
820 break;
821 case BTRFS_BG_SZ_SMALL:
822 small++;
823 break;
824 case BTRFS_BG_SZ_MEDIUM:
825 medium++;
826 break;
827 case BTRFS_BG_SZ_LARGE:
828 large++;
829 break;
830 }
831 }
832 up_read(&sinfo->groups_sem);
833 }
834 return sysfs_emit(buf, "none %u\n"
835 "small %u\n"
836 "medium %u\n"
837 "large %u\n",
838 none, small, medium, large);
839}
840
841#ifdef CONFIG_BTRFS_DEBUG
842/*
843 * Request chunk allocation with current chunk size.
844 */
845static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj,
846 struct kobj_attribute *a,
847 const char *buf, size_t len)
848{
849 struct btrfs_space_info *space_info = to_space_info(kobj);
850 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
851 struct btrfs_trans_handle *trans;
852 bool val;
853 int ret;
854
855 if (!capable(CAP_SYS_ADMIN))
856 return -EPERM;
857
858 if (sb_rdonly(fs_info->sb))
859 return -EROFS;
860
861 ret = kstrtobool(buf, &val);
862 if (ret)
863 return ret;
864
865 if (!val)
866 return -EINVAL;
867
868 /*
869 * This is unsafe to be called from sysfs context and may cause
870 * unexpected problems.
871 */
872 trans = btrfs_start_transaction(fs_info->tree_root, 0);
873 if (IS_ERR(trans))
874 return PTR_ERR(trans);
875 ret = btrfs_force_chunk_alloc(trans, space_info->flags);
876 btrfs_end_transaction(trans);
877
878 if (ret == 1)
879 return len;
880
881 return -ENOSPC;
882}
883BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store);
884
885#endif
886
887SPACE_INFO_ATTR(flags);
888SPACE_INFO_ATTR(total_bytes);
889SPACE_INFO_ATTR(bytes_used);
890SPACE_INFO_ATTR(bytes_pinned);
891SPACE_INFO_ATTR(bytes_reserved);
892SPACE_INFO_ATTR(bytes_may_use);
893SPACE_INFO_ATTR(bytes_readonly);
894SPACE_INFO_ATTR(bytes_zone_unusable);
895SPACE_INFO_ATTR(disk_used);
896SPACE_INFO_ATTR(disk_total);
897BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store);
898BTRFS_ATTR(space_info, size_classes, btrfs_size_classes_show);
899
900static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj,
901 struct kobj_attribute *a,
902 char *buf)
903{
904 struct btrfs_space_info *space_info = to_space_info(kobj);
905
906 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->bg_reclaim_threshold));
907}
908
909static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj,
910 struct kobj_attribute *a,
911 const char *buf, size_t len)
912{
913 struct btrfs_space_info *space_info = to_space_info(kobj);
914 int thresh;
915 int ret;
916
917 ret = kstrtoint(buf, 10, &thresh);
918 if (ret)
919 return ret;
920
921 if (thresh < 0 || thresh > 100)
922 return -EINVAL;
923
924 WRITE_ONCE(space_info->bg_reclaim_threshold, thresh);
925
926 return len;
927}
928
929BTRFS_ATTR_RW(space_info, bg_reclaim_threshold,
930 btrfs_sinfo_bg_reclaim_threshold_show,
931 btrfs_sinfo_bg_reclaim_threshold_store);
932
933/*
934 * Allocation information about block group types.
935 *
936 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/
937 */
938static struct attribute *space_info_attrs[] = {
939 BTRFS_ATTR_PTR(space_info, flags),
940 BTRFS_ATTR_PTR(space_info, total_bytes),
941 BTRFS_ATTR_PTR(space_info, bytes_used),
942 BTRFS_ATTR_PTR(space_info, bytes_pinned),
943 BTRFS_ATTR_PTR(space_info, bytes_reserved),
944 BTRFS_ATTR_PTR(space_info, bytes_may_use),
945 BTRFS_ATTR_PTR(space_info, bytes_readonly),
946 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
947 BTRFS_ATTR_PTR(space_info, disk_used),
948 BTRFS_ATTR_PTR(space_info, disk_total),
949 BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold),
950 BTRFS_ATTR_PTR(space_info, chunk_size),
951 BTRFS_ATTR_PTR(space_info, size_classes),
952#ifdef CONFIG_BTRFS_DEBUG
953 BTRFS_ATTR_PTR(space_info, force_chunk_alloc),
954#endif
955 NULL,
956};
957ATTRIBUTE_GROUPS(space_info);
958
959static void space_info_release(struct kobject *kobj)
960{
961 struct btrfs_space_info *sinfo = to_space_info(kobj);
962 kfree(sinfo);
963}
964
965static const struct kobj_type space_info_ktype = {
966 .sysfs_ops = &kobj_sysfs_ops,
967 .release = space_info_release,
968 .default_groups = space_info_groups,
969};
970
971/*
972 * Allocation information about block groups.
973 *
974 * Path: /sys/fs/btrfs/<uuid>/allocation/
975 */
976static const struct attribute *allocation_attrs[] = {
977 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
978 BTRFS_ATTR_PTR(allocation, global_rsv_size),
979 NULL,
980};
981
982static ssize_t btrfs_label_show(struct kobject *kobj,
983 struct kobj_attribute *a, char *buf)
984{
985 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
986 char *label = fs_info->super_copy->label;
987 ssize_t ret;
988
989 spin_lock(&fs_info->super_lock);
990 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label);
991 spin_unlock(&fs_info->super_lock);
992
993 return ret;
994}
995
996static ssize_t btrfs_label_store(struct kobject *kobj,
997 struct kobj_attribute *a,
998 const char *buf, size_t len)
999{
1000 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1001 size_t p_len;
1002
1003 if (!fs_info)
1004 return -EPERM;
1005
1006 if (sb_rdonly(fs_info->sb))
1007 return -EROFS;
1008
1009 /*
1010 * p_len is the len until the first occurrence of either
1011 * '\n' or '\0'
1012 */
1013 p_len = strcspn(buf, "\n");
1014
1015 if (p_len >= BTRFS_LABEL_SIZE)
1016 return -EINVAL;
1017
1018 spin_lock(&fs_info->super_lock);
1019 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
1020 memcpy(fs_info->super_copy->label, buf, p_len);
1021 spin_unlock(&fs_info->super_lock);
1022
1023 /*
1024 * We don't want to do full transaction commit from inside sysfs
1025 */
1026 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
1027 wake_up_process(fs_info->transaction_kthread);
1028
1029 return len;
1030}
1031BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
1032
1033static ssize_t btrfs_nodesize_show(struct kobject *kobj,
1034 struct kobj_attribute *a, char *buf)
1035{
1036 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1037
1038 return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize);
1039}
1040
1041BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
1042
1043static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
1044 struct kobj_attribute *a, char *buf)
1045{
1046 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1047
1048 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
1049}
1050
1051BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
1052
1053static ssize_t btrfs_commit_stats_show(struct kobject *kobj,
1054 struct kobj_attribute *a, char *buf)
1055{
1056 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1057
1058 return sysfs_emit(buf,
1059 "commits %llu\n"
1060 "last_commit_ms %llu\n"
1061 "max_commit_ms %llu\n"
1062 "total_commit_ms %llu\n",
1063 fs_info->commit_stats.commit_count,
1064 div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC),
1065 div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC),
1066 div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC));
1067}
1068
1069static ssize_t btrfs_commit_stats_store(struct kobject *kobj,
1070 struct kobj_attribute *a,
1071 const char *buf, size_t len)
1072{
1073 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1074 unsigned long val;
1075 int ret;
1076
1077 if (!fs_info)
1078 return -EPERM;
1079
1080 if (!capable(CAP_SYS_RESOURCE))
1081 return -EPERM;
1082
1083 ret = kstrtoul(buf, 10, &val);
1084 if (ret)
1085 return ret;
1086 if (val)
1087 return -EINVAL;
1088
1089 WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0);
1090
1091 return len;
1092}
1093BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store);
1094
1095static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
1096 struct kobj_attribute *a, char *buf)
1097{
1098 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1099
1100 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
1101}
1102
1103BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
1104
1105static ssize_t quota_override_show(struct kobject *kobj,
1106 struct kobj_attribute *a, char *buf)
1107{
1108 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1109 int quota_override;
1110
1111 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1112 return sysfs_emit(buf, "%d\n", quota_override);
1113}
1114
1115static ssize_t quota_override_store(struct kobject *kobj,
1116 struct kobj_attribute *a,
1117 const char *buf, size_t len)
1118{
1119 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1120 unsigned long knob;
1121 int err;
1122
1123 if (!fs_info)
1124 return -EPERM;
1125
1126 if (!capable(CAP_SYS_RESOURCE))
1127 return -EPERM;
1128
1129 err = kstrtoul(buf, 10, &knob);
1130 if (err)
1131 return err;
1132 if (knob > 1)
1133 return -EINVAL;
1134
1135 if (knob)
1136 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1137 else
1138 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1139
1140 return len;
1141}
1142
1143BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
1144
1145static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
1146 struct kobj_attribute *a, char *buf)
1147{
1148 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1149
1150 return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid);
1151}
1152
1153BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
1154
1155static ssize_t btrfs_checksum_show(struct kobject *kobj,
1156 struct kobj_attribute *a, char *buf)
1157{
1158 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1159 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
1160
1161 return sysfs_emit(buf, "%s (%s)\n",
1162 btrfs_super_csum_name(csum_type),
1163 crypto_shash_driver_name(fs_info->csum_shash));
1164}
1165
1166BTRFS_ATTR(, checksum, btrfs_checksum_show);
1167
1168static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
1169 struct kobj_attribute *a, char *buf)
1170{
1171 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1172 const char *str;
1173
1174 switch (READ_ONCE(fs_info->exclusive_operation)) {
1175 case BTRFS_EXCLOP_NONE:
1176 str = "none\n";
1177 break;
1178 case BTRFS_EXCLOP_BALANCE:
1179 str = "balance\n";
1180 break;
1181 case BTRFS_EXCLOP_BALANCE_PAUSED:
1182 str = "balance paused\n";
1183 break;
1184 case BTRFS_EXCLOP_DEV_ADD:
1185 str = "device add\n";
1186 break;
1187 case BTRFS_EXCLOP_DEV_REMOVE:
1188 str = "device remove\n";
1189 break;
1190 case BTRFS_EXCLOP_DEV_REPLACE:
1191 str = "device replace\n";
1192 break;
1193 case BTRFS_EXCLOP_RESIZE:
1194 str = "resize\n";
1195 break;
1196 case BTRFS_EXCLOP_SWAP_ACTIVATE:
1197 str = "swap activate\n";
1198 break;
1199 default:
1200 str = "UNKNOWN\n";
1201 break;
1202 }
1203 return sysfs_emit(buf, "%s", str);
1204}
1205BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
1206
1207static ssize_t btrfs_generation_show(struct kobject *kobj,
1208 struct kobj_attribute *a, char *buf)
1209{
1210 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1211
1212 return sysfs_emit(buf, "%llu\n", btrfs_get_fs_generation(fs_info));
1213}
1214BTRFS_ATTR(, generation, btrfs_generation_show);
1215
1216static ssize_t btrfs_temp_fsid_show(struct kobject *kobj,
1217 struct kobj_attribute *a, char *buf)
1218{
1219 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1220
1221 return sysfs_emit(buf, "%d\n", fs_info->fs_devices->temp_fsid);
1222}
1223BTRFS_ATTR(, temp_fsid, btrfs_temp_fsid_show);
1224
1225static const char * const btrfs_read_policy_name[] = { "pid" };
1226
1227static ssize_t btrfs_read_policy_show(struct kobject *kobj,
1228 struct kobj_attribute *a, char *buf)
1229{
1230 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1231 const enum btrfs_read_policy policy = READ_ONCE(fs_devices->read_policy);
1232 ssize_t ret = 0;
1233 int i;
1234
1235 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1236 if (policy == i)
1237 ret += sysfs_emit_at(buf, ret, "%s[%s]",
1238 (ret == 0 ? "" : " "),
1239 btrfs_read_policy_name[i]);
1240 else
1241 ret += sysfs_emit_at(buf, ret, "%s%s",
1242 (ret == 0 ? "" : " "),
1243 btrfs_read_policy_name[i]);
1244 }
1245
1246 ret += sysfs_emit_at(buf, ret, "\n");
1247
1248 return ret;
1249}
1250
1251static ssize_t btrfs_read_policy_store(struct kobject *kobj,
1252 struct kobj_attribute *a,
1253 const char *buf, size_t len)
1254{
1255 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1256 int i;
1257
1258 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1259 if (sysfs_streq(buf, btrfs_read_policy_name[i])) {
1260 if (i != READ_ONCE(fs_devices->read_policy)) {
1261 WRITE_ONCE(fs_devices->read_policy, i);
1262 btrfs_info(fs_devices->fs_info,
1263 "read policy set to '%s'",
1264 btrfs_read_policy_name[i]);
1265 }
1266 return len;
1267 }
1268 }
1269
1270 return -EINVAL;
1271}
1272BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
1273
1274static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
1275 struct kobj_attribute *a,
1276 char *buf)
1277{
1278 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1279
1280 return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
1281}
1282
1283static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
1284 struct kobj_attribute *a,
1285 const char *buf, size_t len)
1286{
1287 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1288 int thresh;
1289 int ret;
1290
1291 ret = kstrtoint(buf, 10, &thresh);
1292 if (ret)
1293 return ret;
1294
1295#ifdef CONFIG_BTRFS_DEBUG
1296 if (thresh != 0 && (thresh > 100))
1297 return -EINVAL;
1298#else
1299 if (thresh != 0 && (thresh <= 50 || thresh > 100))
1300 return -EINVAL;
1301#endif
1302
1303 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
1304
1305 return len;
1306}
1307BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
1308 btrfs_bg_reclaim_threshold_store);
1309
1310#ifdef CONFIG_BTRFS_DEBUG
1311static ssize_t btrfs_offload_csum_show(struct kobject *kobj,
1312 struct kobj_attribute *a, char *buf)
1313{
1314 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1315
1316 switch (READ_ONCE(fs_devices->offload_csum_mode)) {
1317 case BTRFS_OFFLOAD_CSUM_AUTO:
1318 return sysfs_emit(buf, "auto\n");
1319 case BTRFS_OFFLOAD_CSUM_FORCE_ON:
1320 return sysfs_emit(buf, "1\n");
1321 case BTRFS_OFFLOAD_CSUM_FORCE_OFF:
1322 return sysfs_emit(buf, "0\n");
1323 default:
1324 WARN_ON(1);
1325 return -EINVAL;
1326 }
1327}
1328
1329static ssize_t btrfs_offload_csum_store(struct kobject *kobj,
1330 struct kobj_attribute *a, const char *buf,
1331 size_t len)
1332{
1333 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1334 int ret;
1335 bool val;
1336
1337 ret = kstrtobool(buf, &val);
1338 if (ret == 0)
1339 WRITE_ONCE(fs_devices->offload_csum_mode,
1340 val ? BTRFS_OFFLOAD_CSUM_FORCE_ON : BTRFS_OFFLOAD_CSUM_FORCE_OFF);
1341 else if (ret == -EINVAL && sysfs_streq(buf, "auto"))
1342 WRITE_ONCE(fs_devices->offload_csum_mode, BTRFS_OFFLOAD_CSUM_AUTO);
1343 else
1344 return -EINVAL;
1345
1346 return len;
1347}
1348BTRFS_ATTR_RW(, offload_csum, btrfs_offload_csum_show, btrfs_offload_csum_store);
1349#endif
1350
1351/*
1352 * Per-filesystem information and stats.
1353 *
1354 * Path: /sys/fs/btrfs/<uuid>/
1355 */
1356static const struct attribute *btrfs_attrs[] = {
1357 BTRFS_ATTR_PTR(, label),
1358 BTRFS_ATTR_PTR(, nodesize),
1359 BTRFS_ATTR_PTR(, sectorsize),
1360 BTRFS_ATTR_PTR(, clone_alignment),
1361 BTRFS_ATTR_PTR(, quota_override),
1362 BTRFS_ATTR_PTR(, metadata_uuid),
1363 BTRFS_ATTR_PTR(, checksum),
1364 BTRFS_ATTR_PTR(, exclusive_operation),
1365 BTRFS_ATTR_PTR(, generation),
1366 BTRFS_ATTR_PTR(, read_policy),
1367 BTRFS_ATTR_PTR(, bg_reclaim_threshold),
1368 BTRFS_ATTR_PTR(, commit_stats),
1369 BTRFS_ATTR_PTR(, temp_fsid),
1370#ifdef CONFIG_BTRFS_DEBUG
1371 BTRFS_ATTR_PTR(, offload_csum),
1372#endif
1373 NULL,
1374};
1375
1376static void btrfs_release_fsid_kobj(struct kobject *kobj)
1377{
1378 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
1379
1380 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
1381 complete(&fs_devs->kobj_unregister);
1382}
1383
1384static const struct kobj_type btrfs_ktype = {
1385 .sysfs_ops = &kobj_sysfs_ops,
1386 .release = btrfs_release_fsid_kobj,
1387};
1388
1389static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
1390{
1391 if (kobj->ktype != &btrfs_ktype)
1392 return NULL;
1393 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
1394}
1395
1396static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1397{
1398 if (kobj->ktype != &btrfs_ktype)
1399 return NULL;
1400 return to_fs_devs(kobj)->fs_info;
1401}
1402
1403static struct kobject *get_btrfs_kobj(struct kobject *kobj)
1404{
1405 while (kobj) {
1406 if (kobj->ktype == &btrfs_ktype)
1407 return kobj;
1408 kobj = kobj->parent;
1409 }
1410 return NULL;
1411}
1412
1413#define NUM_FEATURE_BITS 64
1414#define BTRFS_FEATURE_NAME_MAX 13
1415static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1416static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1417
1418static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) ==
1419 ARRAY_SIZE(btrfs_feature_attrs));
1420static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) ==
1421 ARRAY_SIZE(btrfs_feature_attrs[0]));
1422
1423static const u64 supported_feature_masks[FEAT_MAX] = {
1424 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1425 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1426 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1427};
1428
1429static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1430{
1431 int set;
1432
1433 for (set = 0; set < FEAT_MAX; set++) {
1434 int i;
1435 struct attribute *attrs[2];
1436 struct attribute_group agroup = {
1437 .name = "features",
1438 .attrs = attrs,
1439 };
1440 u64 features = get_features(fs_info, set);
1441 features &= ~supported_feature_masks[set];
1442
1443 if (!features)
1444 continue;
1445
1446 attrs[1] = NULL;
1447 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1448 struct btrfs_feature_attr *fa;
1449
1450 if (!(features & (1ULL << i)))
1451 continue;
1452
1453 fa = &btrfs_feature_attrs[set][i];
1454 attrs[0] = &fa->kobj_attr.attr;
1455 if (add) {
1456 int ret;
1457 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1458 &agroup);
1459 if (ret)
1460 return ret;
1461 } else
1462 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1463 &agroup);
1464 }
1465
1466 }
1467 return 0;
1468}
1469
1470static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1471{
1472 if (fs_devs->devinfo_kobj) {
1473 kobject_del(fs_devs->devinfo_kobj);
1474 kobject_put(fs_devs->devinfo_kobj);
1475 fs_devs->devinfo_kobj = NULL;
1476 }
1477
1478 if (fs_devs->devices_kobj) {
1479 kobject_del(fs_devs->devices_kobj);
1480 kobject_put(fs_devs->devices_kobj);
1481 fs_devs->devices_kobj = NULL;
1482 }
1483
1484 if (fs_devs->fsid_kobj.state_initialized) {
1485 kobject_del(&fs_devs->fsid_kobj);
1486 kobject_put(&fs_devs->fsid_kobj);
1487 wait_for_completion(&fs_devs->kobj_unregister);
1488 }
1489}
1490
1491/* when fs_devs is NULL it will remove all fsid kobject */
1492void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1493{
1494 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1495
1496 if (fs_devs) {
1497 __btrfs_sysfs_remove_fsid(fs_devs);
1498 return;
1499 }
1500
1501 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1502 __btrfs_sysfs_remove_fsid(fs_devs);
1503 }
1504}
1505
1506static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1507{
1508 struct btrfs_device *device;
1509 struct btrfs_fs_devices *seed;
1510
1511 list_for_each_entry(device, &fs_devices->devices, dev_list)
1512 btrfs_sysfs_remove_device(device);
1513
1514 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1515 list_for_each_entry(device, &seed->devices, dev_list)
1516 btrfs_sysfs_remove_device(device);
1517 }
1518}
1519
1520void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1521{
1522 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1523
1524 sysfs_remove_link(fsid_kobj, "bdi");
1525
1526 if (fs_info->space_info_kobj) {
1527 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1528 kobject_del(fs_info->space_info_kobj);
1529 kobject_put(fs_info->space_info_kobj);
1530 }
1531 if (fs_info->discard_kobj) {
1532 sysfs_remove_files(fs_info->discard_kobj, discard_attrs);
1533 kobject_del(fs_info->discard_kobj);
1534 kobject_put(fs_info->discard_kobj);
1535 }
1536#ifdef CONFIG_BTRFS_DEBUG
1537 if (fs_info->debug_kobj) {
1538 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1539 kobject_del(fs_info->debug_kobj);
1540 kobject_put(fs_info->debug_kobj);
1541 }
1542#endif
1543 addrm_unknown_feature_attrs(fs_info, false);
1544 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1545 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1546 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1547}
1548
1549static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1550 [FEAT_COMPAT] = "compat",
1551 [FEAT_COMPAT_RO] = "compat_ro",
1552 [FEAT_INCOMPAT] = "incompat",
1553};
1554
1555const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1556{
1557 return btrfs_feature_set_names[set];
1558}
1559
1560char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1561{
1562 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1563 int len = 0;
1564 int i;
1565 char *str;
1566
1567 str = kmalloc(bufsize, GFP_KERNEL);
1568 if (!str)
1569 return str;
1570
1571 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1572 const char *name;
1573
1574 if (!(flags & (1ULL << i)))
1575 continue;
1576
1577 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1578 len += scnprintf(str + len, bufsize - len, "%s%s",
1579 len ? "," : "", name);
1580 }
1581
1582 return str;
1583}
1584
1585static void init_feature_attrs(void)
1586{
1587 struct btrfs_feature_attr *fa;
1588 int set, i;
1589
1590 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1591 memset(btrfs_unknown_feature_names, 0,
1592 sizeof(btrfs_unknown_feature_names));
1593
1594 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1595 struct btrfs_feature_attr *sfa;
1596 struct attribute *a = btrfs_supported_feature_attrs[i];
1597 int bit;
1598 sfa = attr_to_btrfs_feature_attr(a);
1599 bit = ilog2(sfa->feature_bit);
1600 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1601
1602 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1603 }
1604
1605 for (set = 0; set < FEAT_MAX; set++) {
1606 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1607 char *name = btrfs_unknown_feature_names[set][i];
1608 fa = &btrfs_feature_attrs[set][i];
1609
1610 if (fa->kobj_attr.attr.name)
1611 continue;
1612
1613 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1614 btrfs_feature_set_names[set], i);
1615
1616 fa->kobj_attr.attr.name = name;
1617 fa->kobj_attr.attr.mode = S_IRUGO;
1618 fa->feature_set = set;
1619 fa->feature_bit = 1ULL << i;
1620 }
1621 }
1622}
1623
1624/*
1625 * Create a sysfs entry for a given block group type at path
1626 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1627 */
1628void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1629{
1630 struct btrfs_fs_info *fs_info = cache->fs_info;
1631 struct btrfs_space_info *space_info = cache->space_info;
1632 struct raid_kobject *rkobj;
1633 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1634 unsigned int nofs_flag;
1635 int ret;
1636
1637 /*
1638 * Setup a NOFS context because kobject_add(), deep in its call chain,
1639 * does GFP_KERNEL allocations, and we are often called in a context
1640 * where if reclaim is triggered we can deadlock (we are either holding
1641 * a transaction handle or some lock required for a transaction
1642 * commit).
1643 */
1644 nofs_flag = memalloc_nofs_save();
1645
1646 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1647 if (!rkobj) {
1648 memalloc_nofs_restore(nofs_flag);
1649 btrfs_warn(cache->fs_info,
1650 "couldn't alloc memory for raid level kobject");
1651 return;
1652 }
1653
1654 rkobj->flags = cache->flags;
1655 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1656
1657 /*
1658 * We call this either on mount, or if we've created a block group for a
1659 * new index type while running (i.e. when restriping). The running
1660 * case is tricky because we could race with other threads, so we need
1661 * to have this check to make sure we didn't already init the kobject.
1662 *
1663 * We don't have to protect on the free side because it only happens on
1664 * unmount.
1665 */
1666 spin_lock(&space_info->lock);
1667 if (space_info->block_group_kobjs[index]) {
1668 spin_unlock(&space_info->lock);
1669 kobject_put(&rkobj->kobj);
1670 return;
1671 } else {
1672 space_info->block_group_kobjs[index] = &rkobj->kobj;
1673 }
1674 spin_unlock(&space_info->lock);
1675
1676 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1677 btrfs_bg_type_to_raid_name(rkobj->flags));
1678 memalloc_nofs_restore(nofs_flag);
1679 if (ret) {
1680 spin_lock(&space_info->lock);
1681 space_info->block_group_kobjs[index] = NULL;
1682 spin_unlock(&space_info->lock);
1683 kobject_put(&rkobj->kobj);
1684 btrfs_warn(fs_info,
1685 "failed to add kobject for block cache, ignoring");
1686 return;
1687 }
1688}
1689
1690/*
1691 * Remove sysfs directories for all block group types of a given space info and
1692 * the space info as well
1693 */
1694void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1695{
1696 int i;
1697
1698 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1699 struct kobject *kobj;
1700
1701 kobj = space_info->block_group_kobjs[i];
1702 space_info->block_group_kobjs[i] = NULL;
1703 if (kobj) {
1704 kobject_del(kobj);
1705 kobject_put(kobj);
1706 }
1707 }
1708 kobject_del(&space_info->kobj);
1709 kobject_put(&space_info->kobj);
1710}
1711
1712static const char *alloc_name(u64 flags)
1713{
1714 switch (flags) {
1715 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1716 return "mixed";
1717 case BTRFS_BLOCK_GROUP_METADATA:
1718 return "metadata";
1719 case BTRFS_BLOCK_GROUP_DATA:
1720 return "data";
1721 case BTRFS_BLOCK_GROUP_SYSTEM:
1722 return "system";
1723 default:
1724 WARN_ON(1);
1725 return "invalid-combination";
1726 }
1727}
1728
1729/*
1730 * Create a sysfs entry for a space info type at path
1731 * /sys/fs/btrfs/UUID/allocation/TYPE
1732 */
1733int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1734 struct btrfs_space_info *space_info)
1735{
1736 int ret;
1737
1738 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1739 fs_info->space_info_kobj, "%s",
1740 alloc_name(space_info->flags));
1741 if (ret) {
1742 kobject_put(&space_info->kobj);
1743 return ret;
1744 }
1745
1746 return 0;
1747}
1748
1749void btrfs_sysfs_remove_device(struct btrfs_device *device)
1750{
1751 struct kobject *devices_kobj;
1752
1753 /*
1754 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1755 * fs_info::fs_devices.
1756 */
1757 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1758 ASSERT(devices_kobj);
1759
1760 if (device->bdev)
1761 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1762
1763 if (device->devid_kobj.state_initialized) {
1764 kobject_del(&device->devid_kobj);
1765 kobject_put(&device->devid_kobj);
1766 wait_for_completion(&device->kobj_unregister);
1767 }
1768}
1769
1770static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1771 struct kobj_attribute *a,
1772 char *buf)
1773{
1774 int val;
1775 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1776 devid_kobj);
1777
1778 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1779
1780 return sysfs_emit(buf, "%d\n", val);
1781}
1782BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1783
1784static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1785 struct kobj_attribute *a, char *buf)
1786{
1787 int val;
1788 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1789 devid_kobj);
1790
1791 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1792
1793 return sysfs_emit(buf, "%d\n", val);
1794}
1795BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1796
1797static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1798 struct kobj_attribute *a,
1799 char *buf)
1800{
1801 int val;
1802 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1803 devid_kobj);
1804
1805 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1806
1807 return sysfs_emit(buf, "%d\n", val);
1808}
1809BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1810
1811static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
1812 struct kobj_attribute *a,
1813 char *buf)
1814{
1815 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1816 devid_kobj);
1817
1818 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max));
1819}
1820
1821static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
1822 struct kobj_attribute *a,
1823 const char *buf, size_t len)
1824{
1825 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1826 devid_kobj);
1827 char *endptr;
1828 unsigned long long limit;
1829
1830 limit = memparse(buf, &endptr);
1831 /* There could be trailing '\n', also catch any typos after the value. */
1832 endptr = skip_spaces(endptr);
1833 if (*endptr != 0)
1834 return -EINVAL;
1835 WRITE_ONCE(device->scrub_speed_max, limit);
1836 return len;
1837}
1838BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show,
1839 btrfs_devinfo_scrub_speed_max_store);
1840
1841static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1842 struct kobj_attribute *a, char *buf)
1843{
1844 int val;
1845 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1846 devid_kobj);
1847
1848 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1849
1850 return sysfs_emit(buf, "%d\n", val);
1851}
1852BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1853
1854static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj,
1855 struct kobj_attribute *a, char *buf)
1856{
1857 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1858 devid_kobj);
1859
1860 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid);
1861}
1862BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show);
1863
1864static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
1865 struct kobj_attribute *a, char *buf)
1866{
1867 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1868 devid_kobj);
1869
1870 if (!device->dev_stats_valid)
1871 return sysfs_emit(buf, "invalid\n");
1872
1873 /*
1874 * Print all at once so we get a snapshot of all values from the same
1875 * time. Keep them in sync and in order of definition of
1876 * btrfs_dev_stat_values.
1877 */
1878 return sysfs_emit(buf,
1879 "write_errs %d\n"
1880 "read_errs %d\n"
1881 "flush_errs %d\n"
1882 "corruption_errs %d\n"
1883 "generation_errs %d\n",
1884 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS),
1885 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS),
1886 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS),
1887 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS),
1888 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS));
1889}
1890BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show);
1891
1892/*
1893 * Information about one device.
1894 *
1895 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/
1896 */
1897static struct attribute *devid_attrs[] = {
1898 BTRFS_ATTR_PTR(devid, error_stats),
1899 BTRFS_ATTR_PTR(devid, fsid),
1900 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1901 BTRFS_ATTR_PTR(devid, missing),
1902 BTRFS_ATTR_PTR(devid, replace_target),
1903 BTRFS_ATTR_PTR(devid, scrub_speed_max),
1904 BTRFS_ATTR_PTR(devid, writeable),
1905 NULL
1906};
1907ATTRIBUTE_GROUPS(devid);
1908
1909static void btrfs_release_devid_kobj(struct kobject *kobj)
1910{
1911 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1912 devid_kobj);
1913
1914 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1915 complete(&device->kobj_unregister);
1916}
1917
1918static const struct kobj_type devid_ktype = {
1919 .sysfs_ops = &kobj_sysfs_ops,
1920 .default_groups = devid_groups,
1921 .release = btrfs_release_devid_kobj,
1922};
1923
1924int btrfs_sysfs_add_device(struct btrfs_device *device)
1925{
1926 int ret;
1927 unsigned int nofs_flag;
1928 struct kobject *devices_kobj;
1929 struct kobject *devinfo_kobj;
1930
1931 /*
1932 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
1933 * for the seed fs_devices
1934 */
1935 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1936 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
1937 ASSERT(devices_kobj);
1938 ASSERT(devinfo_kobj);
1939
1940 nofs_flag = memalloc_nofs_save();
1941
1942 if (device->bdev) {
1943 struct kobject *disk_kobj = bdev_kobj(device->bdev);
1944
1945 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
1946 if (ret) {
1947 btrfs_warn(device->fs_info,
1948 "creating sysfs device link for devid %llu failed: %d",
1949 device->devid, ret);
1950 goto out;
1951 }
1952 }
1953
1954 init_completion(&device->kobj_unregister);
1955 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
1956 devinfo_kobj, "%llu", device->devid);
1957 if (ret) {
1958 kobject_put(&device->devid_kobj);
1959 btrfs_warn(device->fs_info,
1960 "devinfo init for devid %llu failed: %d",
1961 device->devid, ret);
1962 }
1963
1964out:
1965 memalloc_nofs_restore(nofs_flag);
1966 return ret;
1967}
1968
1969static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
1970{
1971 int ret;
1972 struct btrfs_device *device;
1973 struct btrfs_fs_devices *seed;
1974
1975 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1976 ret = btrfs_sysfs_add_device(device);
1977 if (ret)
1978 goto fail;
1979 }
1980
1981 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1982 list_for_each_entry(device, &seed->devices, dev_list) {
1983 ret = btrfs_sysfs_add_device(device);
1984 if (ret)
1985 goto fail;
1986 }
1987 }
1988
1989 return 0;
1990
1991fail:
1992 btrfs_sysfs_remove_fs_devices(fs_devices);
1993 return ret;
1994}
1995
1996void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1997{
1998 int ret;
1999
2000 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
2001 if (ret)
2002 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
2003 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
2004 &disk_to_dev(bdev->bd_disk)->kobj);
2005}
2006
2007void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
2008
2009{
2010 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2011
2012 /*
2013 * Sprouting changes fsid of the mounted filesystem, rename the fsid
2014 * directory
2015 */
2016 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
2017 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
2018 btrfs_warn(fs_devices->fs_info,
2019 "sysfs: failed to create fsid for sprout");
2020}
2021
2022void btrfs_sysfs_update_devid(struct btrfs_device *device)
2023{
2024 char tmp[24];
2025
2026 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
2027
2028 if (kobject_rename(&device->devid_kobj, tmp))
2029 btrfs_warn(device->fs_devices->fs_info,
2030 "sysfs: failed to update devid for %llu",
2031 device->devid);
2032}
2033
2034/* /sys/fs/btrfs/ entry */
2035static struct kset *btrfs_kset;
2036
2037/*
2038 * Creates:
2039 * /sys/fs/btrfs/UUID
2040 *
2041 * Can be called by the device discovery thread.
2042 */
2043int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
2044{
2045 int error;
2046
2047 init_completion(&fs_devs->kobj_unregister);
2048 fs_devs->fsid_kobj.kset = btrfs_kset;
2049 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
2050 "%pU", fs_devs->fsid);
2051 if (error) {
2052 kobject_put(&fs_devs->fsid_kobj);
2053 return error;
2054 }
2055
2056 fs_devs->devices_kobj = kobject_create_and_add("devices",
2057 &fs_devs->fsid_kobj);
2058 if (!fs_devs->devices_kobj) {
2059 btrfs_err(fs_devs->fs_info,
2060 "failed to init sysfs device interface");
2061 btrfs_sysfs_remove_fsid(fs_devs);
2062 return -ENOMEM;
2063 }
2064
2065 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
2066 &fs_devs->fsid_kobj);
2067 if (!fs_devs->devinfo_kobj) {
2068 btrfs_err(fs_devs->fs_info,
2069 "failed to init sysfs devinfo kobject");
2070 btrfs_sysfs_remove_fsid(fs_devs);
2071 return -ENOMEM;
2072 }
2073
2074 return 0;
2075}
2076
2077int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
2078{
2079 int error;
2080 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
2081 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
2082
2083 error = btrfs_sysfs_add_fs_devices(fs_devs);
2084 if (error)
2085 return error;
2086
2087 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
2088 if (error) {
2089 btrfs_sysfs_remove_fs_devices(fs_devs);
2090 return error;
2091 }
2092
2093 error = sysfs_create_group(fsid_kobj,
2094 &btrfs_feature_attr_group);
2095 if (error)
2096 goto failure;
2097
2098#ifdef CONFIG_BTRFS_DEBUG
2099 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
2100 if (!fs_info->debug_kobj) {
2101 error = -ENOMEM;
2102 goto failure;
2103 }
2104
2105 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
2106 if (error)
2107 goto failure;
2108#endif
2109
2110 /* Discard directory */
2111 fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj);
2112 if (!fs_info->discard_kobj) {
2113 error = -ENOMEM;
2114 goto failure;
2115 }
2116
2117 error = sysfs_create_files(fs_info->discard_kobj, discard_attrs);
2118 if (error)
2119 goto failure;
2120
2121 error = addrm_unknown_feature_attrs(fs_info, true);
2122 if (error)
2123 goto failure;
2124
2125 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
2126 if (error)
2127 goto failure;
2128
2129 fs_info->space_info_kobj = kobject_create_and_add("allocation",
2130 fsid_kobj);
2131 if (!fs_info->space_info_kobj) {
2132 error = -ENOMEM;
2133 goto failure;
2134 }
2135
2136 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
2137 if (error)
2138 goto failure;
2139
2140 return 0;
2141failure:
2142 btrfs_sysfs_remove_mounted(fs_info);
2143 return error;
2144}
2145
2146static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj,
2147 struct kobj_attribute *a,
2148 char *buf)
2149{
2150 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2151 bool enabled;
2152
2153 spin_lock(&fs_info->qgroup_lock);
2154 enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON;
2155 spin_unlock(&fs_info->qgroup_lock);
2156
2157 return sysfs_emit(buf, "%d\n", enabled);
2158}
2159BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show);
2160
2161static ssize_t qgroup_mode_show(struct kobject *qgroups_kobj,
2162 struct kobj_attribute *a,
2163 char *buf)
2164{
2165 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2166 ssize_t ret = 0;
2167
2168 spin_lock(&fs_info->qgroup_lock);
2169 ASSERT(btrfs_qgroup_enabled(fs_info));
2170 switch (btrfs_qgroup_mode(fs_info)) {
2171 case BTRFS_QGROUP_MODE_FULL:
2172 ret = sysfs_emit(buf, "qgroup\n");
2173 break;
2174 case BTRFS_QGROUP_MODE_SIMPLE:
2175 ret = sysfs_emit(buf, "squota\n");
2176 break;
2177 default:
2178 btrfs_warn(fs_info, "unexpected qgroup mode %d\n",
2179 btrfs_qgroup_mode(fs_info));
2180 break;
2181 }
2182 spin_unlock(&fs_info->qgroup_lock);
2183
2184 return ret;
2185}
2186BTRFS_ATTR(qgroups, mode, qgroup_mode_show);
2187
2188static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj,
2189 struct kobj_attribute *a,
2190 char *buf)
2191{
2192 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2193 bool inconsistent;
2194
2195 spin_lock(&fs_info->qgroup_lock);
2196 inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT);
2197 spin_unlock(&fs_info->qgroup_lock);
2198
2199 return sysfs_emit(buf, "%d\n", inconsistent);
2200}
2201BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show);
2202
2203static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj,
2204 struct kobj_attribute *a,
2205 char *buf)
2206{
2207 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2208 u8 result;
2209
2210 spin_lock(&fs_info->qgroup_lock);
2211 result = fs_info->qgroup_drop_subtree_thres;
2212 spin_unlock(&fs_info->qgroup_lock);
2213
2214 return sysfs_emit(buf, "%d\n", result);
2215}
2216
2217static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj,
2218 struct kobj_attribute *a,
2219 const char *buf, size_t len)
2220{
2221 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2222 u8 new_thres;
2223 int ret;
2224
2225 ret = kstrtou8(buf, 10, &new_thres);
2226 if (ret)
2227 return -EINVAL;
2228
2229 if (new_thres > BTRFS_MAX_LEVEL)
2230 return -EINVAL;
2231
2232 spin_lock(&fs_info->qgroup_lock);
2233 fs_info->qgroup_drop_subtree_thres = new_thres;
2234 spin_unlock(&fs_info->qgroup_lock);
2235
2236 return len;
2237}
2238BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show,
2239 qgroup_drop_subtree_thres_store);
2240
2241/*
2242 * Qgroups global info
2243 *
2244 * Path: /sys/fs/btrfs/<uuid>/qgroups/
2245 */
2246static struct attribute *qgroups_attrs[] = {
2247 BTRFS_ATTR_PTR(qgroups, enabled),
2248 BTRFS_ATTR_PTR(qgroups, inconsistent),
2249 BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold),
2250 BTRFS_ATTR_PTR(qgroups, mode),
2251 NULL
2252};
2253ATTRIBUTE_GROUPS(qgroups);
2254
2255static void qgroups_release(struct kobject *kobj)
2256{
2257 kfree(kobj);
2258}
2259
2260static const struct kobj_type qgroups_ktype = {
2261 .sysfs_ops = &kobj_sysfs_ops,
2262 .default_groups = qgroups_groups,
2263 .release = qgroups_release,
2264};
2265
2266static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
2267{
2268 return to_fs_info(kobj->parent->parent);
2269}
2270
2271#define QGROUP_ATTR(_member, _show_name) \
2272static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
2273 struct kobj_attribute *a, \
2274 char *buf) \
2275{ \
2276 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2277 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2278 struct btrfs_qgroup, kobj); \
2279 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
2280} \
2281BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
2282
2283#define QGROUP_RSV_ATTR(_name, _type) \
2284static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
2285 struct kobj_attribute *a, \
2286 char *buf) \
2287{ \
2288 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2289 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2290 struct btrfs_qgroup, kobj); \
2291 return btrfs_show_u64(&qgroup->rsv.values[_type], \
2292 &fs_info->qgroup_lock, buf); \
2293} \
2294BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
2295
2296QGROUP_ATTR(rfer, referenced);
2297QGROUP_ATTR(excl, exclusive);
2298QGROUP_ATTR(max_rfer, max_referenced);
2299QGROUP_ATTR(max_excl, max_exclusive);
2300QGROUP_ATTR(lim_flags, limit_flags);
2301QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
2302QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
2303QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
2304
2305/*
2306 * Qgroup information.
2307 *
2308 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/
2309 */
2310static struct attribute *qgroup_attrs[] = {
2311 BTRFS_ATTR_PTR(qgroup, referenced),
2312 BTRFS_ATTR_PTR(qgroup, exclusive),
2313 BTRFS_ATTR_PTR(qgroup, max_referenced),
2314 BTRFS_ATTR_PTR(qgroup, max_exclusive),
2315 BTRFS_ATTR_PTR(qgroup, limit_flags),
2316 BTRFS_ATTR_PTR(qgroup, rsv_data),
2317 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
2318 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
2319 NULL
2320};
2321ATTRIBUTE_GROUPS(qgroup);
2322
2323static void qgroup_release(struct kobject *kobj)
2324{
2325 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
2326
2327 memset(&qgroup->kobj, 0, sizeof(*kobj));
2328}
2329
2330static const struct kobj_type qgroup_ktype = {
2331 .sysfs_ops = &kobj_sysfs_ops,
2332 .release = qgroup_release,
2333 .default_groups = qgroup_groups,
2334};
2335
2336int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
2337 struct btrfs_qgroup *qgroup)
2338{
2339 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
2340 int ret;
2341
2342 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2343 return 0;
2344 if (qgroup->kobj.state_initialized)
2345 return 0;
2346 if (!qgroups_kobj)
2347 return -EINVAL;
2348
2349 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
2350 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
2351 btrfs_qgroup_subvolid(qgroup->qgroupid));
2352 if (ret < 0)
2353 kobject_put(&qgroup->kobj);
2354
2355 return ret;
2356}
2357
2358void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
2359{
2360 struct btrfs_qgroup *qgroup;
2361 struct btrfs_qgroup *next;
2362
2363 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2364 return;
2365
2366 rbtree_postorder_for_each_entry_safe(qgroup, next,
2367 &fs_info->qgroup_tree, node)
2368 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
2369 if (fs_info->qgroups_kobj) {
2370 kobject_del(fs_info->qgroups_kobj);
2371 kobject_put(fs_info->qgroups_kobj);
2372 fs_info->qgroups_kobj = NULL;
2373 }
2374}
2375
2376/* Called when qgroups get initialized, thus there is no need for locking */
2377int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
2378{
2379 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2380 struct btrfs_qgroup *qgroup;
2381 struct btrfs_qgroup *next;
2382 int ret = 0;
2383
2384 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2385 return 0;
2386
2387 ASSERT(fsid_kobj);
2388 if (fs_info->qgroups_kobj)
2389 return 0;
2390
2391 fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
2392 if (!fs_info->qgroups_kobj)
2393 return -ENOMEM;
2394
2395 ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype,
2396 fsid_kobj, "qgroups");
2397 if (ret < 0)
2398 goto out;
2399
2400 rbtree_postorder_for_each_entry_safe(qgroup, next,
2401 &fs_info->qgroup_tree, node) {
2402 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
2403 if (ret < 0)
2404 goto out;
2405 }
2406
2407out:
2408 if (ret < 0)
2409 btrfs_sysfs_del_qgroups(fs_info);
2410 return ret;
2411}
2412
2413void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
2414 struct btrfs_qgroup *qgroup)
2415{
2416 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
2417 return;
2418
2419 if (qgroup->kobj.state_initialized) {
2420 kobject_del(&qgroup->kobj);
2421 kobject_put(&qgroup->kobj);
2422 }
2423}
2424
2425/*
2426 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
2427 * values in superblock. Call after any changes to incompat/compat_ro flags
2428 */
2429void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info)
2430{
2431 struct kobject *fsid_kobj;
2432 int ret;
2433
2434 if (!fs_info)
2435 return;
2436
2437 fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2438 if (!fsid_kobj->state_initialized)
2439 return;
2440
2441 ret = sysfs_update_group(fsid_kobj, &btrfs_feature_attr_group);
2442 if (ret < 0)
2443 btrfs_warn(fs_info,
2444 "failed to update /sys/fs/btrfs/%pU/features: %d",
2445 fs_info->fs_devices->fsid, ret);
2446}
2447
2448int __init btrfs_init_sysfs(void)
2449{
2450 int ret;
2451
2452 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
2453 if (!btrfs_kset)
2454 return -ENOMEM;
2455
2456 init_feature_attrs();
2457 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2458 if (ret)
2459 goto out2;
2460 ret = sysfs_merge_group(&btrfs_kset->kobj,
2461 &btrfs_static_feature_attr_group);
2462 if (ret)
2463 goto out_remove_group;
2464
2465#ifdef CONFIG_BTRFS_DEBUG
2466 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2467 if (ret) {
2468 sysfs_unmerge_group(&btrfs_kset->kobj,
2469 &btrfs_static_feature_attr_group);
2470 goto out_remove_group;
2471 }
2472#endif
2473
2474 return 0;
2475
2476out_remove_group:
2477 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2478out2:
2479 kset_unregister(btrfs_kset);
2480
2481 return ret;
2482}
2483
2484void __cold btrfs_exit_sysfs(void)
2485{
2486 sysfs_unmerge_group(&btrfs_kset->kobj,
2487 &btrfs_static_feature_attr_group);
2488 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2489#ifdef CONFIG_BTRFS_DEBUG
2490 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2491#endif
2492 kset_unregister(btrfs_kset);
2493}