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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#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_EXPERIMENTAL
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_EXPERIMENTAL
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 "ignoremetacsums",
389 "ignoresuperflags",
390 "all",
391};
392
393static ssize_t supported_rescue_options_show(struct kobject *kobj,
394 struct kobj_attribute *a,
395 char *buf)
396{
397 ssize_t ret = 0;
398 int i;
399
400 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
401 ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]);
402 ret += sysfs_emit_at(buf, ret, "\n");
403 return ret;
404}
405BTRFS_ATTR(static_feature, supported_rescue_options,
406 supported_rescue_options_show);
407
408static ssize_t supported_sectorsizes_show(struct kobject *kobj,
409 struct kobj_attribute *a,
410 char *buf)
411{
412 ssize_t ret = 0;
413
414 /* An artificial limit to only support 4K and PAGE_SIZE */
415 if (PAGE_SIZE > SZ_4K)
416 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K);
417 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE);
418
419 return ret;
420}
421BTRFS_ATTR(static_feature, supported_sectorsizes,
422 supported_sectorsizes_show);
423
424static ssize_t acl_show(struct kobject *kobj, struct kobj_attribute *a, char *buf)
425{
426 return sysfs_emit(buf, "%d\n", IS_ENABLED(CONFIG_BTRFS_FS_POSIX_ACL));
427}
428BTRFS_ATTR(static_feature, acl, acl_show);
429
430static ssize_t temp_fsid_supported_show(struct kobject *kobj,
431 struct kobj_attribute *a, char *buf)
432{
433 return sysfs_emit(buf, "0\n");
434}
435BTRFS_ATTR(static_feature, temp_fsid, temp_fsid_supported_show);
436
437/*
438 * Features which only depend on kernel version.
439 *
440 * These are listed in /sys/fs/btrfs/features along with
441 * btrfs_supported_feature_attrs.
442 */
443static struct attribute *btrfs_supported_static_feature_attrs[] = {
444 BTRFS_ATTR_PTR(static_feature, acl),
445 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
446 BTRFS_ATTR_PTR(static_feature, supported_checksums),
447 BTRFS_ATTR_PTR(static_feature, send_stream_version),
448 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
449 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
450 BTRFS_ATTR_PTR(static_feature, temp_fsid),
451 NULL
452};
453
454static const struct attribute_group btrfs_static_feature_attr_group = {
455 .name = "features",
456 .attrs = btrfs_supported_static_feature_attrs,
457};
458
459/*
460 * Discard statistics and tunables
461 */
462#define discard_to_fs_info(_kobj) to_fs_info(get_btrfs_kobj(_kobj))
463
464static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
465 struct kobj_attribute *a,
466 char *buf)
467{
468 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
469
470 return sysfs_emit(buf, "%lld\n",
471 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
472}
473BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
474
475static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
476 struct kobj_attribute *a,
477 char *buf)
478{
479 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
480
481 return sysfs_emit(buf, "%d\n",
482 atomic_read(&fs_info->discard_ctl.discardable_extents));
483}
484BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
485
486static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
487 struct kobj_attribute *a,
488 char *buf)
489{
490 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
491
492 return sysfs_emit(buf, "%llu\n",
493 fs_info->discard_ctl.discard_bitmap_bytes);
494}
495BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
496
497static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
498 struct kobj_attribute *a,
499 char *buf)
500{
501 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
502
503 return sysfs_emit(buf, "%lld\n",
504 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
505}
506BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
507
508static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
509 struct kobj_attribute *a,
510 char *buf)
511{
512 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
513
514 return sysfs_emit(buf, "%llu\n",
515 fs_info->discard_ctl.discard_extent_bytes);
516}
517BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
518
519static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
520 struct kobj_attribute *a,
521 char *buf)
522{
523 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
524
525 return sysfs_emit(buf, "%u\n",
526 READ_ONCE(fs_info->discard_ctl.iops_limit));
527}
528
529static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
530 struct kobj_attribute *a,
531 const char *buf, size_t len)
532{
533 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
534 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
535 u32 iops_limit;
536 int ret;
537
538 ret = kstrtou32(buf, 10, &iops_limit);
539 if (ret)
540 return -EINVAL;
541
542 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
543 btrfs_discard_calc_delay(discard_ctl);
544 btrfs_discard_schedule_work(discard_ctl, true);
545 return len;
546}
547BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
548 btrfs_discard_iops_limit_store);
549
550static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
551 struct kobj_attribute *a,
552 char *buf)
553{
554 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
555
556 return sysfs_emit(buf, "%u\n",
557 READ_ONCE(fs_info->discard_ctl.kbps_limit));
558}
559
560static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
561 struct kobj_attribute *a,
562 const char *buf, size_t len)
563{
564 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
565 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
566 u32 kbps_limit;
567 int ret;
568
569 ret = kstrtou32(buf, 10, &kbps_limit);
570 if (ret)
571 return -EINVAL;
572
573 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
574 btrfs_discard_schedule_work(discard_ctl, true);
575 return len;
576}
577BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
578 btrfs_discard_kbps_limit_store);
579
580static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
581 struct kobj_attribute *a,
582 char *buf)
583{
584 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
585
586 return sysfs_emit(buf, "%llu\n",
587 READ_ONCE(fs_info->discard_ctl.max_discard_size));
588}
589
590static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
591 struct kobj_attribute *a,
592 const char *buf, size_t len)
593{
594 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
595 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
596 u64 max_discard_size;
597 int ret;
598
599 ret = kstrtou64(buf, 10, &max_discard_size);
600 if (ret)
601 return -EINVAL;
602
603 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
604
605 return len;
606}
607BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
608 btrfs_discard_max_discard_size_store);
609
610/*
611 * Per-filesystem stats for discard (when mounted with discard=async).
612 *
613 * Path: /sys/fs/btrfs/<uuid>/discard/
614 */
615static const struct attribute *discard_attrs[] = {
616 BTRFS_ATTR_PTR(discard, discardable_bytes),
617 BTRFS_ATTR_PTR(discard, discardable_extents),
618 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
619 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
620 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
621 BTRFS_ATTR_PTR(discard, iops_limit),
622 BTRFS_ATTR_PTR(discard, kbps_limit),
623 BTRFS_ATTR_PTR(discard, max_discard_size),
624 NULL,
625};
626
627#ifdef CONFIG_BTRFS_DEBUG
628
629/*
630 * Per-filesystem runtime debugging exported via sysfs.
631 *
632 * Path: /sys/fs/btrfs/UUID/debug/
633 */
634static const struct attribute *btrfs_debug_mount_attrs[] = {
635 NULL,
636};
637
638/*
639 * Runtime debugging exported via sysfs, applies to all mounted filesystems.
640 *
641 * Path: /sys/fs/btrfs/debug
642 */
643static struct attribute *btrfs_debug_feature_attrs[] = {
644 NULL
645};
646
647static const struct attribute_group btrfs_debug_feature_attr_group = {
648 .name = "debug",
649 .attrs = btrfs_debug_feature_attrs,
650};
651
652#endif
653
654static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
655{
656 u64 val;
657 if (lock)
658 spin_lock(lock);
659 val = *value_ptr;
660 if (lock)
661 spin_unlock(lock);
662 return sysfs_emit(buf, "%llu\n", val);
663}
664
665static ssize_t global_rsv_size_show(struct kobject *kobj,
666 struct kobj_attribute *ka, char *buf)
667{
668 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
669 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
670 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
671}
672BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
673
674static ssize_t global_rsv_reserved_show(struct kobject *kobj,
675 struct kobj_attribute *a, char *buf)
676{
677 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
678 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
679 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
680}
681BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
682
683#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
684#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
685
686static ssize_t raid_bytes_show(struct kobject *kobj,
687 struct kobj_attribute *attr, char *buf);
688BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
689BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
690
691static ssize_t raid_bytes_show(struct kobject *kobj,
692 struct kobj_attribute *attr, char *buf)
693
694{
695 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
696 struct btrfs_block_group *block_group;
697 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
698 u64 val = 0;
699
700 down_read(&sinfo->groups_sem);
701 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
702 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
703 val += block_group->length;
704 else
705 val += block_group->used;
706 }
707 up_read(&sinfo->groups_sem);
708 return sysfs_emit(buf, "%llu\n", val);
709}
710
711/*
712 * Allocation information about block group profiles.
713 *
714 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/
715 */
716static struct attribute *raid_attrs[] = {
717 BTRFS_ATTR_PTR(raid, total_bytes),
718 BTRFS_ATTR_PTR(raid, used_bytes),
719 NULL
720};
721ATTRIBUTE_GROUPS(raid);
722
723static void release_raid_kobj(struct kobject *kobj)
724{
725 kfree(to_raid_kobj(kobj));
726}
727
728static const struct kobj_type btrfs_raid_ktype = {
729 .sysfs_ops = &kobj_sysfs_ops,
730 .release = release_raid_kobj,
731 .default_groups = raid_groups,
732};
733
734#define SPACE_INFO_ATTR(field) \
735static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
736 struct kobj_attribute *a, \
737 char *buf) \
738{ \
739 struct btrfs_space_info *sinfo = to_space_info(kobj); \
740 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
741} \
742BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
743
744static ssize_t btrfs_chunk_size_show(struct kobject *kobj,
745 struct kobj_attribute *a, char *buf)
746{
747 struct btrfs_space_info *sinfo = to_space_info(kobj);
748
749 return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size));
750}
751
752/*
753 * Store new chunk size in space info. Can be called on a read-only filesystem.
754 *
755 * If the new chunk size value is larger than 10% of free space it is reduced
756 * to match that limit. Alignment must be to 256M and the system chunk size
757 * cannot be set.
758 */
759static ssize_t btrfs_chunk_size_store(struct kobject *kobj,
760 struct kobj_attribute *a,
761 const char *buf, size_t len)
762{
763 struct btrfs_space_info *space_info = to_space_info(kobj);
764 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
765 char *retptr;
766 u64 val;
767
768 if (!capable(CAP_SYS_ADMIN))
769 return -EPERM;
770
771 if (!fs_info->fs_devices)
772 return -EINVAL;
773
774 if (btrfs_is_zoned(fs_info))
775 return -EINVAL;
776
777 /* System block type must not be changed. */
778 if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
779 return -EPERM;
780
781 val = memparse(buf, &retptr);
782 /* There could be trailing '\n', also catch any typos after the value */
783 retptr = skip_spaces(retptr);
784 if (*retptr != 0 || val == 0)
785 return -EINVAL;
786
787 val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE);
788
789 /* Limit stripe size to 10% of available space. */
790 val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val);
791
792 /* Must be multiple of 256M. */
793 val &= ~((u64)SZ_256M - 1);
794
795 /* Must be at least 256M. */
796 if (val < SZ_256M)
797 return -EINVAL;
798
799 btrfs_update_space_info_chunk_size(space_info, val);
800
801 return len;
802}
803
804static ssize_t btrfs_size_classes_show(struct kobject *kobj,
805 struct kobj_attribute *a, char *buf)
806{
807 struct btrfs_space_info *sinfo = to_space_info(kobj);
808 struct btrfs_block_group *bg;
809 u32 none = 0;
810 u32 small = 0;
811 u32 medium = 0;
812 u32 large = 0;
813
814 for (int i = 0; i < BTRFS_NR_RAID_TYPES; ++i) {
815 down_read(&sinfo->groups_sem);
816 list_for_each_entry(bg, &sinfo->block_groups[i], list) {
817 if (!btrfs_block_group_should_use_size_class(bg))
818 continue;
819 switch (bg->size_class) {
820 case BTRFS_BG_SZ_NONE:
821 none++;
822 break;
823 case BTRFS_BG_SZ_SMALL:
824 small++;
825 break;
826 case BTRFS_BG_SZ_MEDIUM:
827 medium++;
828 break;
829 case BTRFS_BG_SZ_LARGE:
830 large++;
831 break;
832 }
833 }
834 up_read(&sinfo->groups_sem);
835 }
836 return sysfs_emit(buf, "none %u\n"
837 "small %u\n"
838 "medium %u\n"
839 "large %u\n",
840 none, small, medium, large);
841}
842
843#ifdef CONFIG_BTRFS_DEBUG
844/*
845 * Request chunk allocation with current chunk size.
846 */
847static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj,
848 struct kobj_attribute *a,
849 const char *buf, size_t len)
850{
851 struct btrfs_space_info *space_info = to_space_info(kobj);
852 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
853 struct btrfs_trans_handle *trans;
854 bool val;
855 int ret;
856
857 if (!capable(CAP_SYS_ADMIN))
858 return -EPERM;
859
860 if (sb_rdonly(fs_info->sb))
861 return -EROFS;
862
863 ret = kstrtobool(buf, &val);
864 if (ret)
865 return ret;
866
867 if (!val)
868 return -EINVAL;
869
870 /*
871 * This is unsafe to be called from sysfs context and may cause
872 * unexpected problems.
873 */
874 trans = btrfs_start_transaction(fs_info->tree_root, 0);
875 if (IS_ERR(trans))
876 return PTR_ERR(trans);
877 ret = btrfs_force_chunk_alloc(trans, space_info->flags);
878 btrfs_end_transaction(trans);
879
880 if (ret == 1)
881 return len;
882
883 return -ENOSPC;
884}
885BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store);
886
887#endif
888
889SPACE_INFO_ATTR(flags);
890SPACE_INFO_ATTR(total_bytes);
891SPACE_INFO_ATTR(bytes_used);
892SPACE_INFO_ATTR(bytes_pinned);
893SPACE_INFO_ATTR(bytes_reserved);
894SPACE_INFO_ATTR(bytes_may_use);
895SPACE_INFO_ATTR(bytes_readonly);
896SPACE_INFO_ATTR(bytes_zone_unusable);
897SPACE_INFO_ATTR(disk_used);
898SPACE_INFO_ATTR(disk_total);
899SPACE_INFO_ATTR(reclaim_count);
900SPACE_INFO_ATTR(reclaim_bytes);
901SPACE_INFO_ATTR(reclaim_errors);
902BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store);
903BTRFS_ATTR(space_info, size_classes, btrfs_size_classes_show);
904
905static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj,
906 struct kobj_attribute *a,
907 char *buf)
908{
909 struct btrfs_space_info *space_info = to_space_info(kobj);
910 ssize_t ret;
911
912 spin_lock(&space_info->lock);
913 ret = sysfs_emit(buf, "%d\n", btrfs_calc_reclaim_threshold(space_info));
914 spin_unlock(&space_info->lock);
915 return ret;
916}
917
918static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj,
919 struct kobj_attribute *a,
920 const char *buf, size_t len)
921{
922 struct btrfs_space_info *space_info = to_space_info(kobj);
923 int thresh;
924 int ret;
925
926 if (READ_ONCE(space_info->dynamic_reclaim))
927 return -EINVAL;
928
929 ret = kstrtoint(buf, 10, &thresh);
930 if (ret)
931 return ret;
932
933 if (thresh < 0 || thresh > 100)
934 return -EINVAL;
935
936 WRITE_ONCE(space_info->bg_reclaim_threshold, thresh);
937
938 return len;
939}
940
941BTRFS_ATTR_RW(space_info, bg_reclaim_threshold,
942 btrfs_sinfo_bg_reclaim_threshold_show,
943 btrfs_sinfo_bg_reclaim_threshold_store);
944
945static ssize_t btrfs_sinfo_dynamic_reclaim_show(struct kobject *kobj,
946 struct kobj_attribute *a,
947 char *buf)
948{
949 struct btrfs_space_info *space_info = to_space_info(kobj);
950
951 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->dynamic_reclaim));
952}
953
954static ssize_t btrfs_sinfo_dynamic_reclaim_store(struct kobject *kobj,
955 struct kobj_attribute *a,
956 const char *buf, size_t len)
957{
958 struct btrfs_space_info *space_info = to_space_info(kobj);
959 int dynamic_reclaim;
960 int ret;
961
962 ret = kstrtoint(buf, 10, &dynamic_reclaim);
963 if (ret)
964 return ret;
965
966 if (dynamic_reclaim < 0)
967 return -EINVAL;
968
969 WRITE_ONCE(space_info->dynamic_reclaim, dynamic_reclaim != 0);
970
971 return len;
972}
973
974BTRFS_ATTR_RW(space_info, dynamic_reclaim,
975 btrfs_sinfo_dynamic_reclaim_show,
976 btrfs_sinfo_dynamic_reclaim_store);
977
978static ssize_t btrfs_sinfo_periodic_reclaim_show(struct kobject *kobj,
979 struct kobj_attribute *a,
980 char *buf)
981{
982 struct btrfs_space_info *space_info = to_space_info(kobj);
983
984 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->periodic_reclaim));
985}
986
987static ssize_t btrfs_sinfo_periodic_reclaim_store(struct kobject *kobj,
988 struct kobj_attribute *a,
989 const char *buf, size_t len)
990{
991 struct btrfs_space_info *space_info = to_space_info(kobj);
992 int periodic_reclaim;
993 int ret;
994
995 ret = kstrtoint(buf, 10, &periodic_reclaim);
996 if (ret)
997 return ret;
998
999 if (periodic_reclaim < 0)
1000 return -EINVAL;
1001
1002 WRITE_ONCE(space_info->periodic_reclaim, periodic_reclaim != 0);
1003
1004 return len;
1005}
1006
1007BTRFS_ATTR_RW(space_info, periodic_reclaim,
1008 btrfs_sinfo_periodic_reclaim_show,
1009 btrfs_sinfo_periodic_reclaim_store);
1010
1011/*
1012 * Allocation information about block group types.
1013 *
1014 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/
1015 */
1016static struct attribute *space_info_attrs[] = {
1017 BTRFS_ATTR_PTR(space_info, flags),
1018 BTRFS_ATTR_PTR(space_info, total_bytes),
1019 BTRFS_ATTR_PTR(space_info, bytes_used),
1020 BTRFS_ATTR_PTR(space_info, bytes_pinned),
1021 BTRFS_ATTR_PTR(space_info, bytes_reserved),
1022 BTRFS_ATTR_PTR(space_info, bytes_may_use),
1023 BTRFS_ATTR_PTR(space_info, bytes_readonly),
1024 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
1025 BTRFS_ATTR_PTR(space_info, disk_used),
1026 BTRFS_ATTR_PTR(space_info, disk_total),
1027 BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold),
1028 BTRFS_ATTR_PTR(space_info, dynamic_reclaim),
1029 BTRFS_ATTR_PTR(space_info, chunk_size),
1030 BTRFS_ATTR_PTR(space_info, size_classes),
1031 BTRFS_ATTR_PTR(space_info, reclaim_count),
1032 BTRFS_ATTR_PTR(space_info, reclaim_bytes),
1033 BTRFS_ATTR_PTR(space_info, reclaim_errors),
1034 BTRFS_ATTR_PTR(space_info, periodic_reclaim),
1035#ifdef CONFIG_BTRFS_DEBUG
1036 BTRFS_ATTR_PTR(space_info, force_chunk_alloc),
1037#endif
1038 NULL,
1039};
1040ATTRIBUTE_GROUPS(space_info);
1041
1042static void space_info_release(struct kobject *kobj)
1043{
1044 struct btrfs_space_info *sinfo = to_space_info(kobj);
1045 kfree(sinfo);
1046}
1047
1048static const struct kobj_type space_info_ktype = {
1049 .sysfs_ops = &kobj_sysfs_ops,
1050 .release = space_info_release,
1051 .default_groups = space_info_groups,
1052};
1053
1054/*
1055 * Allocation information about block groups.
1056 *
1057 * Path: /sys/fs/btrfs/<uuid>/allocation/
1058 */
1059static const struct attribute *allocation_attrs[] = {
1060 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
1061 BTRFS_ATTR_PTR(allocation, global_rsv_size),
1062 NULL,
1063};
1064
1065static ssize_t btrfs_label_show(struct kobject *kobj,
1066 struct kobj_attribute *a, char *buf)
1067{
1068 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1069 char *label = fs_info->super_copy->label;
1070 ssize_t ret;
1071
1072 spin_lock(&fs_info->super_lock);
1073 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label);
1074 spin_unlock(&fs_info->super_lock);
1075
1076 return ret;
1077}
1078
1079static ssize_t btrfs_label_store(struct kobject *kobj,
1080 struct kobj_attribute *a,
1081 const char *buf, size_t len)
1082{
1083 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1084 size_t p_len;
1085
1086 if (!fs_info)
1087 return -EPERM;
1088
1089 if (sb_rdonly(fs_info->sb))
1090 return -EROFS;
1091
1092 /*
1093 * p_len is the len until the first occurrence of either
1094 * '\n' or '\0'
1095 */
1096 p_len = strcspn(buf, "\n");
1097
1098 if (p_len >= BTRFS_LABEL_SIZE)
1099 return -EINVAL;
1100
1101 spin_lock(&fs_info->super_lock);
1102 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
1103 memcpy(fs_info->super_copy->label, buf, p_len);
1104 spin_unlock(&fs_info->super_lock);
1105
1106 /*
1107 * We don't want to do full transaction commit from inside sysfs
1108 */
1109 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
1110 wake_up_process(fs_info->transaction_kthread);
1111
1112 return len;
1113}
1114BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
1115
1116static ssize_t btrfs_nodesize_show(struct kobject *kobj,
1117 struct kobj_attribute *a, char *buf)
1118{
1119 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1120
1121 return sysfs_emit(buf, "%u\n", fs_info->nodesize);
1122}
1123
1124BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
1125
1126static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
1127 struct kobj_attribute *a, char *buf)
1128{
1129 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1130
1131 return sysfs_emit(buf, "%u\n", fs_info->sectorsize);
1132}
1133
1134BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
1135
1136static ssize_t btrfs_commit_stats_show(struct kobject *kobj,
1137 struct kobj_attribute *a, char *buf)
1138{
1139 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1140
1141 return sysfs_emit(buf,
1142 "commits %llu\n"
1143 "last_commit_ms %llu\n"
1144 "max_commit_ms %llu\n"
1145 "total_commit_ms %llu\n",
1146 fs_info->commit_stats.commit_count,
1147 div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC),
1148 div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC),
1149 div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC));
1150}
1151
1152static ssize_t btrfs_commit_stats_store(struct kobject *kobj,
1153 struct kobj_attribute *a,
1154 const char *buf, size_t len)
1155{
1156 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1157 unsigned long val;
1158 int ret;
1159
1160 if (!fs_info)
1161 return -EPERM;
1162
1163 if (!capable(CAP_SYS_RESOURCE))
1164 return -EPERM;
1165
1166 ret = kstrtoul(buf, 10, &val);
1167 if (ret)
1168 return ret;
1169 if (val)
1170 return -EINVAL;
1171
1172 WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0);
1173
1174 return len;
1175}
1176BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store);
1177
1178static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
1179 struct kobj_attribute *a, char *buf)
1180{
1181 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1182
1183 return sysfs_emit(buf, "%u\n", fs_info->sectorsize);
1184}
1185
1186BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
1187
1188static ssize_t quota_override_show(struct kobject *kobj,
1189 struct kobj_attribute *a, char *buf)
1190{
1191 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1192 int quota_override;
1193
1194 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1195 return sysfs_emit(buf, "%d\n", quota_override);
1196}
1197
1198static ssize_t quota_override_store(struct kobject *kobj,
1199 struct kobj_attribute *a,
1200 const char *buf, size_t len)
1201{
1202 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1203 unsigned long knob;
1204 int err;
1205
1206 if (!fs_info)
1207 return -EPERM;
1208
1209 if (!capable(CAP_SYS_RESOURCE))
1210 return -EPERM;
1211
1212 err = kstrtoul(buf, 10, &knob);
1213 if (err)
1214 return err;
1215 if (knob > 1)
1216 return -EINVAL;
1217
1218 if (knob)
1219 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1220 else
1221 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
1222
1223 return len;
1224}
1225
1226BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
1227
1228static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
1229 struct kobj_attribute *a, char *buf)
1230{
1231 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1232
1233 return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid);
1234}
1235
1236BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
1237
1238static ssize_t btrfs_checksum_show(struct kobject *kobj,
1239 struct kobj_attribute *a, char *buf)
1240{
1241 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1242 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
1243
1244 return sysfs_emit(buf, "%s (%s)\n",
1245 btrfs_super_csum_name(csum_type),
1246 crypto_shash_driver_name(fs_info->csum_shash));
1247}
1248
1249BTRFS_ATTR(, checksum, btrfs_checksum_show);
1250
1251static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
1252 struct kobj_attribute *a, char *buf)
1253{
1254 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1255 const char *str;
1256
1257 switch (READ_ONCE(fs_info->exclusive_operation)) {
1258 case BTRFS_EXCLOP_NONE:
1259 str = "none\n";
1260 break;
1261 case BTRFS_EXCLOP_BALANCE:
1262 str = "balance\n";
1263 break;
1264 case BTRFS_EXCLOP_BALANCE_PAUSED:
1265 str = "balance paused\n";
1266 break;
1267 case BTRFS_EXCLOP_DEV_ADD:
1268 str = "device add\n";
1269 break;
1270 case BTRFS_EXCLOP_DEV_REMOVE:
1271 str = "device remove\n";
1272 break;
1273 case BTRFS_EXCLOP_DEV_REPLACE:
1274 str = "device replace\n";
1275 break;
1276 case BTRFS_EXCLOP_RESIZE:
1277 str = "resize\n";
1278 break;
1279 case BTRFS_EXCLOP_SWAP_ACTIVATE:
1280 str = "swap activate\n";
1281 break;
1282 default:
1283 str = "UNKNOWN\n";
1284 break;
1285 }
1286 return sysfs_emit(buf, "%s", str);
1287}
1288BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
1289
1290static ssize_t btrfs_generation_show(struct kobject *kobj,
1291 struct kobj_attribute *a, char *buf)
1292{
1293 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1294
1295 return sysfs_emit(buf, "%llu\n", btrfs_get_fs_generation(fs_info));
1296}
1297BTRFS_ATTR(, generation, btrfs_generation_show);
1298
1299static ssize_t btrfs_temp_fsid_show(struct kobject *kobj,
1300 struct kobj_attribute *a, char *buf)
1301{
1302 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1303
1304 return sysfs_emit(buf, "%d\n", fs_info->fs_devices->temp_fsid);
1305}
1306BTRFS_ATTR(, temp_fsid, btrfs_temp_fsid_show);
1307
1308static const char * const btrfs_read_policy_name[] = { "pid" };
1309
1310static ssize_t btrfs_read_policy_show(struct kobject *kobj,
1311 struct kobj_attribute *a, char *buf)
1312{
1313 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1314 const enum btrfs_read_policy policy = READ_ONCE(fs_devices->read_policy);
1315 ssize_t ret = 0;
1316 int i;
1317
1318 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1319 if (policy == i)
1320 ret += sysfs_emit_at(buf, ret, "%s[%s]",
1321 (ret == 0 ? "" : " "),
1322 btrfs_read_policy_name[i]);
1323 else
1324 ret += sysfs_emit_at(buf, ret, "%s%s",
1325 (ret == 0 ? "" : " "),
1326 btrfs_read_policy_name[i]);
1327 }
1328
1329 ret += sysfs_emit_at(buf, ret, "\n");
1330
1331 return ret;
1332}
1333
1334static ssize_t btrfs_read_policy_store(struct kobject *kobj,
1335 struct kobj_attribute *a,
1336 const char *buf, size_t len)
1337{
1338 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1339 int i;
1340
1341 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1342 if (sysfs_streq(buf, btrfs_read_policy_name[i])) {
1343 if (i != READ_ONCE(fs_devices->read_policy)) {
1344 WRITE_ONCE(fs_devices->read_policy, i);
1345 btrfs_info(fs_devices->fs_info,
1346 "read policy set to '%s'",
1347 btrfs_read_policy_name[i]);
1348 }
1349 return len;
1350 }
1351 }
1352
1353 return -EINVAL;
1354}
1355BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
1356
1357static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
1358 struct kobj_attribute *a,
1359 char *buf)
1360{
1361 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1362
1363 return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
1364}
1365
1366static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
1367 struct kobj_attribute *a,
1368 const char *buf, size_t len)
1369{
1370 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1371 int thresh;
1372 int ret;
1373
1374 ret = kstrtoint(buf, 10, &thresh);
1375 if (ret)
1376 return ret;
1377
1378#ifdef CONFIG_BTRFS_DEBUG
1379 if (thresh != 0 && (thresh > 100))
1380 return -EINVAL;
1381#else
1382 if (thresh != 0 && (thresh <= 50 || thresh > 100))
1383 return -EINVAL;
1384#endif
1385
1386 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
1387
1388 return len;
1389}
1390BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
1391 btrfs_bg_reclaim_threshold_store);
1392
1393#ifdef CONFIG_BTRFS_EXPERIMENTAL
1394static ssize_t btrfs_offload_csum_show(struct kobject *kobj,
1395 struct kobj_attribute *a, char *buf)
1396{
1397 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1398
1399 switch (READ_ONCE(fs_devices->offload_csum_mode)) {
1400 case BTRFS_OFFLOAD_CSUM_AUTO:
1401 return sysfs_emit(buf, "auto\n");
1402 case BTRFS_OFFLOAD_CSUM_FORCE_ON:
1403 return sysfs_emit(buf, "1\n");
1404 case BTRFS_OFFLOAD_CSUM_FORCE_OFF:
1405 return sysfs_emit(buf, "0\n");
1406 default:
1407 WARN_ON(1);
1408 return -EINVAL;
1409 }
1410}
1411
1412static ssize_t btrfs_offload_csum_store(struct kobject *kobj,
1413 struct kobj_attribute *a, const char *buf,
1414 size_t len)
1415{
1416 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1417 int ret;
1418 bool val;
1419
1420 ret = kstrtobool(buf, &val);
1421 if (ret == 0)
1422 WRITE_ONCE(fs_devices->offload_csum_mode,
1423 val ? BTRFS_OFFLOAD_CSUM_FORCE_ON : BTRFS_OFFLOAD_CSUM_FORCE_OFF);
1424 else if (ret == -EINVAL && sysfs_streq(buf, "auto"))
1425 WRITE_ONCE(fs_devices->offload_csum_mode, BTRFS_OFFLOAD_CSUM_AUTO);
1426 else
1427 return -EINVAL;
1428
1429 return len;
1430}
1431BTRFS_ATTR_RW(, offload_csum, btrfs_offload_csum_show, btrfs_offload_csum_store);
1432#endif
1433
1434/*
1435 * Per-filesystem information and stats.
1436 *
1437 * Path: /sys/fs/btrfs/<uuid>/
1438 */
1439static const struct attribute *btrfs_attrs[] = {
1440 BTRFS_ATTR_PTR(, label),
1441 BTRFS_ATTR_PTR(, nodesize),
1442 BTRFS_ATTR_PTR(, sectorsize),
1443 BTRFS_ATTR_PTR(, clone_alignment),
1444 BTRFS_ATTR_PTR(, quota_override),
1445 BTRFS_ATTR_PTR(, metadata_uuid),
1446 BTRFS_ATTR_PTR(, checksum),
1447 BTRFS_ATTR_PTR(, exclusive_operation),
1448 BTRFS_ATTR_PTR(, generation),
1449 BTRFS_ATTR_PTR(, read_policy),
1450 BTRFS_ATTR_PTR(, bg_reclaim_threshold),
1451 BTRFS_ATTR_PTR(, commit_stats),
1452 BTRFS_ATTR_PTR(, temp_fsid),
1453#ifdef CONFIG_BTRFS_EXPERIMENTAL
1454 BTRFS_ATTR_PTR(, offload_csum),
1455#endif
1456 NULL,
1457};
1458
1459static void btrfs_release_fsid_kobj(struct kobject *kobj)
1460{
1461 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
1462
1463 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
1464 complete(&fs_devs->kobj_unregister);
1465}
1466
1467static const struct kobj_type btrfs_ktype = {
1468 .sysfs_ops = &kobj_sysfs_ops,
1469 .release = btrfs_release_fsid_kobj,
1470};
1471
1472static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
1473{
1474 if (kobj->ktype != &btrfs_ktype)
1475 return NULL;
1476 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
1477}
1478
1479static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1480{
1481 if (kobj->ktype != &btrfs_ktype)
1482 return NULL;
1483 return to_fs_devs(kobj)->fs_info;
1484}
1485
1486static struct kobject *get_btrfs_kobj(struct kobject *kobj)
1487{
1488 while (kobj) {
1489 if (kobj->ktype == &btrfs_ktype)
1490 return kobj;
1491 kobj = kobj->parent;
1492 }
1493 return NULL;
1494}
1495
1496#define NUM_FEATURE_BITS 64
1497#define BTRFS_FEATURE_NAME_MAX 13
1498static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1499static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1500
1501static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) ==
1502 ARRAY_SIZE(btrfs_feature_attrs));
1503static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) ==
1504 ARRAY_SIZE(btrfs_feature_attrs[0]));
1505
1506static const u64 supported_feature_masks[FEAT_MAX] = {
1507 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1508 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1509 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1510};
1511
1512static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1513{
1514 int set;
1515
1516 for (set = 0; set < FEAT_MAX; set++) {
1517 int i;
1518 struct attribute *attrs[2];
1519 struct attribute_group agroup = {
1520 .name = "features",
1521 .attrs = attrs,
1522 };
1523 u64 features = get_features(fs_info, set);
1524 features &= ~supported_feature_masks[set];
1525
1526 if (!features)
1527 continue;
1528
1529 attrs[1] = NULL;
1530 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1531 struct btrfs_feature_attr *fa;
1532
1533 if (!(features & (1ULL << i)))
1534 continue;
1535
1536 fa = &btrfs_feature_attrs[set][i];
1537 attrs[0] = &fa->kobj_attr.attr;
1538 if (add) {
1539 int ret;
1540 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1541 &agroup);
1542 if (ret)
1543 return ret;
1544 } else
1545 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1546 &agroup);
1547 }
1548
1549 }
1550 return 0;
1551}
1552
1553static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1554{
1555 if (fs_devs->devinfo_kobj) {
1556 kobject_del(fs_devs->devinfo_kobj);
1557 kobject_put(fs_devs->devinfo_kobj);
1558 fs_devs->devinfo_kobj = NULL;
1559 }
1560
1561 if (fs_devs->devices_kobj) {
1562 kobject_del(fs_devs->devices_kobj);
1563 kobject_put(fs_devs->devices_kobj);
1564 fs_devs->devices_kobj = NULL;
1565 }
1566
1567 if (fs_devs->fsid_kobj.state_initialized) {
1568 kobject_del(&fs_devs->fsid_kobj);
1569 kobject_put(&fs_devs->fsid_kobj);
1570 wait_for_completion(&fs_devs->kobj_unregister);
1571 }
1572}
1573
1574/* when fs_devs is NULL it will remove all fsid kobject */
1575void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1576{
1577 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1578
1579 if (fs_devs) {
1580 __btrfs_sysfs_remove_fsid(fs_devs);
1581 return;
1582 }
1583
1584 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1585 __btrfs_sysfs_remove_fsid(fs_devs);
1586 }
1587}
1588
1589static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1590{
1591 struct btrfs_device *device;
1592 struct btrfs_fs_devices *seed;
1593
1594 list_for_each_entry(device, &fs_devices->devices, dev_list)
1595 btrfs_sysfs_remove_device(device);
1596
1597 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1598 list_for_each_entry(device, &seed->devices, dev_list)
1599 btrfs_sysfs_remove_device(device);
1600 }
1601}
1602
1603void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1604{
1605 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1606
1607 sysfs_remove_link(fsid_kobj, "bdi");
1608
1609 if (fs_info->space_info_kobj) {
1610 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1611 kobject_del(fs_info->space_info_kobj);
1612 kobject_put(fs_info->space_info_kobj);
1613 }
1614 if (fs_info->discard_kobj) {
1615 sysfs_remove_files(fs_info->discard_kobj, discard_attrs);
1616 kobject_del(fs_info->discard_kobj);
1617 kobject_put(fs_info->discard_kobj);
1618 }
1619#ifdef CONFIG_BTRFS_DEBUG
1620 if (fs_info->debug_kobj) {
1621 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1622 kobject_del(fs_info->debug_kobj);
1623 kobject_put(fs_info->debug_kobj);
1624 }
1625#endif
1626 addrm_unknown_feature_attrs(fs_info, false);
1627 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1628 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1629 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1630}
1631
1632static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1633 [FEAT_COMPAT] = "compat",
1634 [FEAT_COMPAT_RO] = "compat_ro",
1635 [FEAT_INCOMPAT] = "incompat",
1636};
1637
1638const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1639{
1640 return btrfs_feature_set_names[set];
1641}
1642
1643char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1644{
1645 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1646 int len = 0;
1647 int i;
1648 char *str;
1649
1650 str = kmalloc(bufsize, GFP_KERNEL);
1651 if (!str)
1652 return str;
1653
1654 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1655 const char *name;
1656
1657 if (!(flags & (1ULL << i)))
1658 continue;
1659
1660 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1661 len += scnprintf(str + len, bufsize - len, "%s%s",
1662 len ? "," : "", name);
1663 }
1664
1665 return str;
1666}
1667
1668static void init_feature_attrs(void)
1669{
1670 struct btrfs_feature_attr *fa;
1671 int set, i;
1672
1673 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1674 memset(btrfs_unknown_feature_names, 0,
1675 sizeof(btrfs_unknown_feature_names));
1676
1677 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1678 struct btrfs_feature_attr *sfa;
1679 struct attribute *a = btrfs_supported_feature_attrs[i];
1680 int bit;
1681 sfa = attr_to_btrfs_feature_attr(a);
1682 bit = ilog2(sfa->feature_bit);
1683 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1684
1685 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1686 }
1687
1688 for (set = 0; set < FEAT_MAX; set++) {
1689 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1690 char *name = btrfs_unknown_feature_names[set][i];
1691 fa = &btrfs_feature_attrs[set][i];
1692
1693 if (fa->kobj_attr.attr.name)
1694 continue;
1695
1696 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1697 btrfs_feature_set_names[set], i);
1698
1699 fa->kobj_attr.attr.name = name;
1700 fa->kobj_attr.attr.mode = S_IRUGO;
1701 fa->feature_set = set;
1702 fa->feature_bit = 1ULL << i;
1703 }
1704 }
1705}
1706
1707/*
1708 * Create a sysfs entry for a given block group type at path
1709 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1710 */
1711void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1712{
1713 struct btrfs_fs_info *fs_info = cache->fs_info;
1714 struct btrfs_space_info *space_info = cache->space_info;
1715 struct raid_kobject *rkobj;
1716 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1717 unsigned int nofs_flag;
1718 int ret;
1719
1720 /*
1721 * Setup a NOFS context because kobject_add(), deep in its call chain,
1722 * does GFP_KERNEL allocations, and we are often called in a context
1723 * where if reclaim is triggered we can deadlock (we are either holding
1724 * a transaction handle or some lock required for a transaction
1725 * commit).
1726 */
1727 nofs_flag = memalloc_nofs_save();
1728
1729 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1730 if (!rkobj) {
1731 memalloc_nofs_restore(nofs_flag);
1732 btrfs_warn(cache->fs_info,
1733 "couldn't alloc memory for raid level kobject");
1734 return;
1735 }
1736
1737 rkobj->flags = cache->flags;
1738 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1739
1740 /*
1741 * We call this either on mount, or if we've created a block group for a
1742 * new index type while running (i.e. when restriping). The running
1743 * case is tricky because we could race with other threads, so we need
1744 * to have this check to make sure we didn't already init the kobject.
1745 *
1746 * We don't have to protect on the free side because it only happens on
1747 * unmount.
1748 */
1749 spin_lock(&space_info->lock);
1750 if (space_info->block_group_kobjs[index]) {
1751 spin_unlock(&space_info->lock);
1752 kobject_put(&rkobj->kobj);
1753 return;
1754 } else {
1755 space_info->block_group_kobjs[index] = &rkobj->kobj;
1756 }
1757 spin_unlock(&space_info->lock);
1758
1759 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1760 btrfs_bg_type_to_raid_name(rkobj->flags));
1761 memalloc_nofs_restore(nofs_flag);
1762 if (ret) {
1763 spin_lock(&space_info->lock);
1764 space_info->block_group_kobjs[index] = NULL;
1765 spin_unlock(&space_info->lock);
1766 kobject_put(&rkobj->kobj);
1767 btrfs_warn(fs_info,
1768 "failed to add kobject for block cache, ignoring");
1769 return;
1770 }
1771}
1772
1773/*
1774 * Remove sysfs directories for all block group types of a given space info and
1775 * the space info as well
1776 */
1777void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1778{
1779 int i;
1780
1781 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1782 struct kobject *kobj;
1783
1784 kobj = space_info->block_group_kobjs[i];
1785 space_info->block_group_kobjs[i] = NULL;
1786 if (kobj) {
1787 kobject_del(kobj);
1788 kobject_put(kobj);
1789 }
1790 }
1791 kobject_del(&space_info->kobj);
1792 kobject_put(&space_info->kobj);
1793}
1794
1795static const char *alloc_name(u64 flags)
1796{
1797 switch (flags) {
1798 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1799 return "mixed";
1800 case BTRFS_BLOCK_GROUP_METADATA:
1801 return "metadata";
1802 case BTRFS_BLOCK_GROUP_DATA:
1803 return "data";
1804 case BTRFS_BLOCK_GROUP_SYSTEM:
1805 return "system";
1806 default:
1807 WARN_ON(1);
1808 return "invalid-combination";
1809 }
1810}
1811
1812/*
1813 * Create a sysfs entry for a space info type at path
1814 * /sys/fs/btrfs/UUID/allocation/TYPE
1815 */
1816int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1817 struct btrfs_space_info *space_info)
1818{
1819 int ret;
1820
1821 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1822 fs_info->space_info_kobj, "%s",
1823 alloc_name(space_info->flags));
1824 if (ret) {
1825 kobject_put(&space_info->kobj);
1826 return ret;
1827 }
1828
1829 return 0;
1830}
1831
1832void btrfs_sysfs_remove_device(struct btrfs_device *device)
1833{
1834 struct kobject *devices_kobj;
1835
1836 /*
1837 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1838 * fs_info::fs_devices.
1839 */
1840 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1841 ASSERT(devices_kobj);
1842
1843 if (device->bdev)
1844 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1845
1846 if (device->devid_kobj.state_initialized) {
1847 kobject_del(&device->devid_kobj);
1848 kobject_put(&device->devid_kobj);
1849 wait_for_completion(&device->kobj_unregister);
1850 }
1851}
1852
1853static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1854 struct kobj_attribute *a,
1855 char *buf)
1856{
1857 int val;
1858 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1859 devid_kobj);
1860
1861 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1862
1863 return sysfs_emit(buf, "%d\n", val);
1864}
1865BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1866
1867static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1868 struct kobj_attribute *a, char *buf)
1869{
1870 int val;
1871 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1872 devid_kobj);
1873
1874 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1875
1876 return sysfs_emit(buf, "%d\n", val);
1877}
1878BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1879
1880static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1881 struct kobj_attribute *a,
1882 char *buf)
1883{
1884 int val;
1885 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1886 devid_kobj);
1887
1888 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1889
1890 return sysfs_emit(buf, "%d\n", val);
1891}
1892BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1893
1894static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
1895 struct kobj_attribute *a,
1896 char *buf)
1897{
1898 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1899 devid_kobj);
1900
1901 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max));
1902}
1903
1904static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
1905 struct kobj_attribute *a,
1906 const char *buf, size_t len)
1907{
1908 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1909 devid_kobj);
1910 char *endptr;
1911 unsigned long long limit;
1912
1913 limit = memparse(buf, &endptr);
1914 /* There could be trailing '\n', also catch any typos after the value. */
1915 endptr = skip_spaces(endptr);
1916 if (*endptr != 0)
1917 return -EINVAL;
1918 WRITE_ONCE(device->scrub_speed_max, limit);
1919 return len;
1920}
1921BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show,
1922 btrfs_devinfo_scrub_speed_max_store);
1923
1924static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1925 struct kobj_attribute *a, char *buf)
1926{
1927 int val;
1928 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1929 devid_kobj);
1930
1931 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1932
1933 return sysfs_emit(buf, "%d\n", val);
1934}
1935BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1936
1937static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj,
1938 struct kobj_attribute *a, char *buf)
1939{
1940 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1941 devid_kobj);
1942
1943 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid);
1944}
1945BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show);
1946
1947static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
1948 struct kobj_attribute *a, char *buf)
1949{
1950 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1951 devid_kobj);
1952
1953 if (!device->dev_stats_valid)
1954 return sysfs_emit(buf, "invalid\n");
1955
1956 /*
1957 * Print all at once so we get a snapshot of all values from the same
1958 * time. Keep them in sync and in order of definition of
1959 * btrfs_dev_stat_values.
1960 */
1961 return sysfs_emit(buf,
1962 "write_errs %d\n"
1963 "read_errs %d\n"
1964 "flush_errs %d\n"
1965 "corruption_errs %d\n"
1966 "generation_errs %d\n",
1967 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS),
1968 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS),
1969 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS),
1970 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS),
1971 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS));
1972}
1973BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show);
1974
1975/*
1976 * Information about one device.
1977 *
1978 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/
1979 */
1980static struct attribute *devid_attrs[] = {
1981 BTRFS_ATTR_PTR(devid, error_stats),
1982 BTRFS_ATTR_PTR(devid, fsid),
1983 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1984 BTRFS_ATTR_PTR(devid, missing),
1985 BTRFS_ATTR_PTR(devid, replace_target),
1986 BTRFS_ATTR_PTR(devid, scrub_speed_max),
1987 BTRFS_ATTR_PTR(devid, writeable),
1988 NULL
1989};
1990ATTRIBUTE_GROUPS(devid);
1991
1992static void btrfs_release_devid_kobj(struct kobject *kobj)
1993{
1994 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1995 devid_kobj);
1996
1997 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1998 complete(&device->kobj_unregister);
1999}
2000
2001static const struct kobj_type devid_ktype = {
2002 .sysfs_ops = &kobj_sysfs_ops,
2003 .default_groups = devid_groups,
2004 .release = btrfs_release_devid_kobj,
2005};
2006
2007int btrfs_sysfs_add_device(struct btrfs_device *device)
2008{
2009 int ret;
2010 unsigned int nofs_flag;
2011 struct kobject *devices_kobj;
2012 struct kobject *devinfo_kobj;
2013
2014 /*
2015 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
2016 * for the seed fs_devices
2017 */
2018 devices_kobj = device->fs_info->fs_devices->devices_kobj;
2019 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
2020 ASSERT(devices_kobj);
2021 ASSERT(devinfo_kobj);
2022
2023 nofs_flag = memalloc_nofs_save();
2024
2025 if (device->bdev) {
2026 struct kobject *disk_kobj = bdev_kobj(device->bdev);
2027
2028 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
2029 if (ret) {
2030 btrfs_warn(device->fs_info,
2031 "creating sysfs device link for devid %llu failed: %d",
2032 device->devid, ret);
2033 goto out;
2034 }
2035 }
2036
2037 init_completion(&device->kobj_unregister);
2038 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
2039 devinfo_kobj, "%llu", device->devid);
2040 if (ret) {
2041 kobject_put(&device->devid_kobj);
2042 btrfs_warn(device->fs_info,
2043 "devinfo init for devid %llu failed: %d",
2044 device->devid, ret);
2045 }
2046
2047out:
2048 memalloc_nofs_restore(nofs_flag);
2049 return ret;
2050}
2051
2052static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
2053{
2054 int ret;
2055 struct btrfs_device *device;
2056 struct btrfs_fs_devices *seed;
2057
2058 list_for_each_entry(device, &fs_devices->devices, dev_list) {
2059 ret = btrfs_sysfs_add_device(device);
2060 if (ret)
2061 goto fail;
2062 }
2063
2064 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
2065 list_for_each_entry(device, &seed->devices, dev_list) {
2066 ret = btrfs_sysfs_add_device(device);
2067 if (ret)
2068 goto fail;
2069 }
2070 }
2071
2072 return 0;
2073
2074fail:
2075 btrfs_sysfs_remove_fs_devices(fs_devices);
2076 return ret;
2077}
2078
2079void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
2080{
2081 int ret;
2082
2083 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
2084 if (ret)
2085 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
2086 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
2087 &disk_to_dev(bdev->bd_disk)->kobj);
2088}
2089
2090void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
2091
2092{
2093 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2094
2095 /*
2096 * Sprouting changes fsid of the mounted filesystem, rename the fsid
2097 * directory
2098 */
2099 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
2100 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
2101 btrfs_warn(fs_devices->fs_info,
2102 "sysfs: failed to create fsid for sprout");
2103}
2104
2105void btrfs_sysfs_update_devid(struct btrfs_device *device)
2106{
2107 char tmp[24];
2108
2109 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
2110
2111 if (kobject_rename(&device->devid_kobj, tmp))
2112 btrfs_warn(device->fs_devices->fs_info,
2113 "sysfs: failed to update devid for %llu",
2114 device->devid);
2115}
2116
2117/* /sys/fs/btrfs/ entry */
2118static struct kset *btrfs_kset;
2119
2120/*
2121 * Creates:
2122 * /sys/fs/btrfs/UUID
2123 *
2124 * Can be called by the device discovery thread.
2125 */
2126int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
2127{
2128 int error;
2129
2130 init_completion(&fs_devs->kobj_unregister);
2131 fs_devs->fsid_kobj.kset = btrfs_kset;
2132 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
2133 "%pU", fs_devs->fsid);
2134 if (error) {
2135 kobject_put(&fs_devs->fsid_kobj);
2136 return error;
2137 }
2138
2139 fs_devs->devices_kobj = kobject_create_and_add("devices",
2140 &fs_devs->fsid_kobj);
2141 if (!fs_devs->devices_kobj) {
2142 btrfs_err(fs_devs->fs_info,
2143 "failed to init sysfs device interface");
2144 btrfs_sysfs_remove_fsid(fs_devs);
2145 return -ENOMEM;
2146 }
2147
2148 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
2149 &fs_devs->fsid_kobj);
2150 if (!fs_devs->devinfo_kobj) {
2151 btrfs_err(fs_devs->fs_info,
2152 "failed to init sysfs devinfo kobject");
2153 btrfs_sysfs_remove_fsid(fs_devs);
2154 return -ENOMEM;
2155 }
2156
2157 return 0;
2158}
2159
2160int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
2161{
2162 int error;
2163 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
2164 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
2165
2166 error = btrfs_sysfs_add_fs_devices(fs_devs);
2167 if (error)
2168 return error;
2169
2170 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
2171 if (error) {
2172 btrfs_sysfs_remove_fs_devices(fs_devs);
2173 return error;
2174 }
2175
2176 error = sysfs_create_group(fsid_kobj,
2177 &btrfs_feature_attr_group);
2178 if (error)
2179 goto failure;
2180
2181#ifdef CONFIG_BTRFS_DEBUG
2182 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
2183 if (!fs_info->debug_kobj) {
2184 error = -ENOMEM;
2185 goto failure;
2186 }
2187
2188 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
2189 if (error)
2190 goto failure;
2191#endif
2192
2193 /* Discard directory */
2194 fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj);
2195 if (!fs_info->discard_kobj) {
2196 error = -ENOMEM;
2197 goto failure;
2198 }
2199
2200 error = sysfs_create_files(fs_info->discard_kobj, discard_attrs);
2201 if (error)
2202 goto failure;
2203
2204 error = addrm_unknown_feature_attrs(fs_info, true);
2205 if (error)
2206 goto failure;
2207
2208 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
2209 if (error)
2210 goto failure;
2211
2212 fs_info->space_info_kobj = kobject_create_and_add("allocation",
2213 fsid_kobj);
2214 if (!fs_info->space_info_kobj) {
2215 error = -ENOMEM;
2216 goto failure;
2217 }
2218
2219 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
2220 if (error)
2221 goto failure;
2222
2223 return 0;
2224failure:
2225 btrfs_sysfs_remove_mounted(fs_info);
2226 return error;
2227}
2228
2229static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj,
2230 struct kobj_attribute *a,
2231 char *buf)
2232{
2233 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2234 bool enabled;
2235
2236 spin_lock(&fs_info->qgroup_lock);
2237 enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON;
2238 spin_unlock(&fs_info->qgroup_lock);
2239
2240 return sysfs_emit(buf, "%d\n", enabled);
2241}
2242BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show);
2243
2244static ssize_t qgroup_mode_show(struct kobject *qgroups_kobj,
2245 struct kobj_attribute *a,
2246 char *buf)
2247{
2248 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2249 ssize_t ret = 0;
2250
2251 spin_lock(&fs_info->qgroup_lock);
2252 ASSERT(btrfs_qgroup_enabled(fs_info));
2253 switch (btrfs_qgroup_mode(fs_info)) {
2254 case BTRFS_QGROUP_MODE_FULL:
2255 ret = sysfs_emit(buf, "qgroup\n");
2256 break;
2257 case BTRFS_QGROUP_MODE_SIMPLE:
2258 ret = sysfs_emit(buf, "squota\n");
2259 break;
2260 default:
2261 btrfs_warn(fs_info, "unexpected qgroup mode %d\n",
2262 btrfs_qgroup_mode(fs_info));
2263 break;
2264 }
2265 spin_unlock(&fs_info->qgroup_lock);
2266
2267 return ret;
2268}
2269BTRFS_ATTR(qgroups, mode, qgroup_mode_show);
2270
2271static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj,
2272 struct kobj_attribute *a,
2273 char *buf)
2274{
2275 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2276 bool inconsistent;
2277
2278 spin_lock(&fs_info->qgroup_lock);
2279 inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT);
2280 spin_unlock(&fs_info->qgroup_lock);
2281
2282 return sysfs_emit(buf, "%d\n", inconsistent);
2283}
2284BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show);
2285
2286static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj,
2287 struct kobj_attribute *a,
2288 char *buf)
2289{
2290 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2291 u8 result;
2292
2293 spin_lock(&fs_info->qgroup_lock);
2294 result = fs_info->qgroup_drop_subtree_thres;
2295 spin_unlock(&fs_info->qgroup_lock);
2296
2297 return sysfs_emit(buf, "%d\n", result);
2298}
2299
2300static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj,
2301 struct kobj_attribute *a,
2302 const char *buf, size_t len)
2303{
2304 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
2305 u8 new_thres;
2306 int ret;
2307
2308 ret = kstrtou8(buf, 10, &new_thres);
2309 if (ret)
2310 return -EINVAL;
2311
2312 if (new_thres > BTRFS_MAX_LEVEL)
2313 return -EINVAL;
2314
2315 spin_lock(&fs_info->qgroup_lock);
2316 fs_info->qgroup_drop_subtree_thres = new_thres;
2317 spin_unlock(&fs_info->qgroup_lock);
2318
2319 return len;
2320}
2321BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show,
2322 qgroup_drop_subtree_thres_store);
2323
2324/*
2325 * Qgroups global info
2326 *
2327 * Path: /sys/fs/btrfs/<uuid>/qgroups/
2328 */
2329static struct attribute *qgroups_attrs[] = {
2330 BTRFS_ATTR_PTR(qgroups, enabled),
2331 BTRFS_ATTR_PTR(qgroups, inconsistent),
2332 BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold),
2333 BTRFS_ATTR_PTR(qgroups, mode),
2334 NULL
2335};
2336ATTRIBUTE_GROUPS(qgroups);
2337
2338static void qgroups_release(struct kobject *kobj)
2339{
2340 kfree(kobj);
2341}
2342
2343static const struct kobj_type qgroups_ktype = {
2344 .sysfs_ops = &kobj_sysfs_ops,
2345 .default_groups = qgroups_groups,
2346 .release = qgroups_release,
2347};
2348
2349static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
2350{
2351 return to_fs_info(kobj->parent->parent);
2352}
2353
2354#define QGROUP_ATTR(_member, _show_name) \
2355static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
2356 struct kobj_attribute *a, \
2357 char *buf) \
2358{ \
2359 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2360 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2361 struct btrfs_qgroup, kobj); \
2362 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
2363} \
2364BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
2365
2366#define QGROUP_RSV_ATTR(_name, _type) \
2367static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
2368 struct kobj_attribute *a, \
2369 char *buf) \
2370{ \
2371 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
2372 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
2373 struct btrfs_qgroup, kobj); \
2374 return btrfs_show_u64(&qgroup->rsv.values[_type], \
2375 &fs_info->qgroup_lock, buf); \
2376} \
2377BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
2378
2379QGROUP_ATTR(rfer, referenced);
2380QGROUP_ATTR(excl, exclusive);
2381QGROUP_ATTR(max_rfer, max_referenced);
2382QGROUP_ATTR(max_excl, max_exclusive);
2383QGROUP_ATTR(lim_flags, limit_flags);
2384QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
2385QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
2386QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
2387
2388/*
2389 * Qgroup information.
2390 *
2391 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/
2392 */
2393static struct attribute *qgroup_attrs[] = {
2394 BTRFS_ATTR_PTR(qgroup, referenced),
2395 BTRFS_ATTR_PTR(qgroup, exclusive),
2396 BTRFS_ATTR_PTR(qgroup, max_referenced),
2397 BTRFS_ATTR_PTR(qgroup, max_exclusive),
2398 BTRFS_ATTR_PTR(qgroup, limit_flags),
2399 BTRFS_ATTR_PTR(qgroup, rsv_data),
2400 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
2401 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
2402 NULL
2403};
2404ATTRIBUTE_GROUPS(qgroup);
2405
2406static void qgroup_release(struct kobject *kobj)
2407{
2408 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
2409
2410 memset(&qgroup->kobj, 0, sizeof(*kobj));
2411}
2412
2413static const struct kobj_type qgroup_ktype = {
2414 .sysfs_ops = &kobj_sysfs_ops,
2415 .release = qgroup_release,
2416 .default_groups = qgroup_groups,
2417};
2418
2419int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
2420 struct btrfs_qgroup *qgroup)
2421{
2422 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
2423 int ret;
2424
2425 if (btrfs_is_testing(fs_info))
2426 return 0;
2427 if (qgroup->kobj.state_initialized)
2428 return 0;
2429 if (!qgroups_kobj)
2430 return -EINVAL;
2431
2432 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
2433 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
2434 btrfs_qgroup_subvolid(qgroup->qgroupid));
2435 if (ret < 0)
2436 kobject_put(&qgroup->kobj);
2437
2438 return ret;
2439}
2440
2441void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
2442{
2443 struct btrfs_qgroup *qgroup;
2444 struct btrfs_qgroup *next;
2445
2446 if (btrfs_is_testing(fs_info))
2447 return;
2448
2449 rbtree_postorder_for_each_entry_safe(qgroup, next,
2450 &fs_info->qgroup_tree, node)
2451 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
2452 if (fs_info->qgroups_kobj) {
2453 kobject_del(fs_info->qgroups_kobj);
2454 kobject_put(fs_info->qgroups_kobj);
2455 fs_info->qgroups_kobj = NULL;
2456 }
2457}
2458
2459/* Called when qgroups get initialized, thus there is no need for locking */
2460int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
2461{
2462 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2463 struct btrfs_qgroup *qgroup;
2464 struct btrfs_qgroup *next;
2465 int ret = 0;
2466
2467 if (btrfs_is_testing(fs_info))
2468 return 0;
2469
2470 ASSERT(fsid_kobj);
2471 if (fs_info->qgroups_kobj)
2472 return 0;
2473
2474 fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
2475 if (!fs_info->qgroups_kobj)
2476 return -ENOMEM;
2477
2478 ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype,
2479 fsid_kobj, "qgroups");
2480 if (ret < 0)
2481 goto out;
2482
2483 rbtree_postorder_for_each_entry_safe(qgroup, next,
2484 &fs_info->qgroup_tree, node) {
2485 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
2486 if (ret < 0)
2487 goto out;
2488 }
2489
2490out:
2491 if (ret < 0)
2492 btrfs_sysfs_del_qgroups(fs_info);
2493 return ret;
2494}
2495
2496void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
2497 struct btrfs_qgroup *qgroup)
2498{
2499 if (btrfs_is_testing(fs_info))
2500 return;
2501
2502 if (qgroup->kobj.state_initialized) {
2503 kobject_del(&qgroup->kobj);
2504 kobject_put(&qgroup->kobj);
2505 }
2506}
2507
2508/*
2509 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
2510 * values in superblock. Call after any changes to incompat/compat_ro flags
2511 */
2512void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info)
2513{
2514 struct kobject *fsid_kobj;
2515 int ret;
2516
2517 if (!fs_info)
2518 return;
2519
2520 fsid_kobj = &fs_info->fs_devices->fsid_kobj;
2521 if (!fsid_kobj->state_initialized)
2522 return;
2523
2524 ret = sysfs_update_group(fsid_kobj, &btrfs_feature_attr_group);
2525 if (ret < 0)
2526 btrfs_warn(fs_info,
2527 "failed to update /sys/fs/btrfs/%pU/features: %d",
2528 fs_info->fs_devices->fsid, ret);
2529}
2530
2531int __init btrfs_init_sysfs(void)
2532{
2533 int ret;
2534
2535 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
2536 if (!btrfs_kset)
2537 return -ENOMEM;
2538
2539 init_feature_attrs();
2540 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2541 if (ret)
2542 goto out2;
2543 ret = sysfs_merge_group(&btrfs_kset->kobj,
2544 &btrfs_static_feature_attr_group);
2545 if (ret)
2546 goto out_remove_group;
2547
2548#ifdef CONFIG_BTRFS_DEBUG
2549 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2550 if (ret) {
2551 sysfs_unmerge_group(&btrfs_kset->kobj,
2552 &btrfs_static_feature_attr_group);
2553 goto out_remove_group;
2554 }
2555#endif
2556
2557 return 0;
2558
2559out_remove_group:
2560 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2561out2:
2562 kset_unregister(btrfs_kset);
2563
2564 return ret;
2565}
2566
2567void __cold btrfs_exit_sysfs(void)
2568{
2569 sysfs_unmerge_group(&btrfs_kset->kobj,
2570 &btrfs_static_feature_attr_group);
2571 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2572#ifdef CONFIG_BTRFS_DEBUG
2573 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2574#endif
2575 kset_unregister(btrfs_kset);
2576}
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/slab.h>
8#include <linux/spinlock.h>
9#include <linux/completion.h>
10#include <linux/buffer_head.h>
11#include <linux/kobject.h>
12#include <linux/bug.h>
13#include <linux/genhd.h>
14#include <linux/debugfs.h>
15
16#include "ctree.h"
17#include "disk-io.h"
18#include "transaction.h"
19#include "sysfs.h"
20#include "volumes.h"
21
22static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
23static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
24
25static u64 get_features(struct btrfs_fs_info *fs_info,
26 enum btrfs_feature_set set)
27{
28 struct btrfs_super_block *disk_super = fs_info->super_copy;
29 if (set == FEAT_COMPAT)
30 return btrfs_super_compat_flags(disk_super);
31 else if (set == FEAT_COMPAT_RO)
32 return btrfs_super_compat_ro_flags(disk_super);
33 else
34 return btrfs_super_incompat_flags(disk_super);
35}
36
37static void set_features(struct btrfs_fs_info *fs_info,
38 enum btrfs_feature_set set, u64 features)
39{
40 struct btrfs_super_block *disk_super = fs_info->super_copy;
41 if (set == FEAT_COMPAT)
42 btrfs_set_super_compat_flags(disk_super, features);
43 else if (set == FEAT_COMPAT_RO)
44 btrfs_set_super_compat_ro_flags(disk_super, features);
45 else
46 btrfs_set_super_incompat_flags(disk_super, features);
47}
48
49static int can_modify_feature(struct btrfs_feature_attr *fa)
50{
51 int val = 0;
52 u64 set, clear;
53 switch (fa->feature_set) {
54 case FEAT_COMPAT:
55 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
56 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
57 break;
58 case FEAT_COMPAT_RO:
59 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
60 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
61 break;
62 case FEAT_INCOMPAT:
63 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
64 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
65 break;
66 default:
67 pr_warn("btrfs: sysfs: unknown feature set %d\n",
68 fa->feature_set);
69 return 0;
70 }
71
72 if (set & fa->feature_bit)
73 val |= 1;
74 if (clear & fa->feature_bit)
75 val |= 2;
76
77 return val;
78}
79
80static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
81 struct kobj_attribute *a, char *buf)
82{
83 int val = 0;
84 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
85 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
86 if (fs_info) {
87 u64 features = get_features(fs_info, fa->feature_set);
88 if (features & fa->feature_bit)
89 val = 1;
90 } else
91 val = can_modify_feature(fa);
92
93 return snprintf(buf, PAGE_SIZE, "%d\n", val);
94}
95
96static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
97 struct kobj_attribute *a,
98 const char *buf, size_t count)
99{
100 struct btrfs_fs_info *fs_info;
101 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
102 u64 features, set, clear;
103 unsigned long val;
104 int ret;
105
106 fs_info = to_fs_info(kobj);
107 if (!fs_info)
108 return -EPERM;
109
110 if (sb_rdonly(fs_info->sb))
111 return -EROFS;
112
113 ret = kstrtoul(skip_spaces(buf), 0, &val);
114 if (ret)
115 return ret;
116
117 if (fa->feature_set == FEAT_COMPAT) {
118 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
119 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
120 } else if (fa->feature_set == FEAT_COMPAT_RO) {
121 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
122 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
123 } else {
124 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
125 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
126 }
127
128 features = get_features(fs_info, fa->feature_set);
129
130 /* Nothing to do */
131 if ((val && (features & fa->feature_bit)) ||
132 (!val && !(features & fa->feature_bit)))
133 return count;
134
135 if ((val && !(set & fa->feature_bit)) ||
136 (!val && !(clear & fa->feature_bit))) {
137 btrfs_info(fs_info,
138 "%sabling feature %s on mounted fs is not supported.",
139 val ? "En" : "Dis", fa->kobj_attr.attr.name);
140 return -EPERM;
141 }
142
143 btrfs_info(fs_info, "%s %s feature flag",
144 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
145
146 spin_lock(&fs_info->super_lock);
147 features = get_features(fs_info, fa->feature_set);
148 if (val)
149 features |= fa->feature_bit;
150 else
151 features &= ~fa->feature_bit;
152 set_features(fs_info, fa->feature_set, features);
153 spin_unlock(&fs_info->super_lock);
154
155 /*
156 * We don't want to do full transaction commit from inside sysfs
157 */
158 btrfs_set_pending(fs_info, COMMIT);
159 wake_up_process(fs_info->transaction_kthread);
160
161 return count;
162}
163
164static umode_t btrfs_feature_visible(struct kobject *kobj,
165 struct attribute *attr, int unused)
166{
167 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
168 umode_t mode = attr->mode;
169
170 if (fs_info) {
171 struct btrfs_feature_attr *fa;
172 u64 features;
173
174 fa = attr_to_btrfs_feature_attr(attr);
175 features = get_features(fs_info, fa->feature_set);
176
177 if (can_modify_feature(fa))
178 mode |= S_IWUSR;
179 else if (!(features & fa->feature_bit))
180 mode = 0;
181 }
182
183 return mode;
184}
185
186BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
187BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
188BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
189BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
190BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
191BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
192BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
193BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
194BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
195BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
196BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
197
198static struct attribute *btrfs_supported_feature_attrs[] = {
199 BTRFS_FEAT_ATTR_PTR(mixed_backref),
200 BTRFS_FEAT_ATTR_PTR(default_subvol),
201 BTRFS_FEAT_ATTR_PTR(mixed_groups),
202 BTRFS_FEAT_ATTR_PTR(compress_lzo),
203 BTRFS_FEAT_ATTR_PTR(compress_zstd),
204 BTRFS_FEAT_ATTR_PTR(big_metadata),
205 BTRFS_FEAT_ATTR_PTR(extended_iref),
206 BTRFS_FEAT_ATTR_PTR(raid56),
207 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
208 BTRFS_FEAT_ATTR_PTR(no_holes),
209 BTRFS_FEAT_ATTR_PTR(free_space_tree),
210 NULL
211};
212
213static const struct attribute_group btrfs_feature_attr_group = {
214 .name = "features",
215 .is_visible = btrfs_feature_visible,
216 .attrs = btrfs_supported_feature_attrs,
217};
218
219static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
220{
221 u64 val;
222 if (lock)
223 spin_lock(lock);
224 val = *value_ptr;
225 if (lock)
226 spin_unlock(lock);
227 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
228}
229
230static ssize_t global_rsv_size_show(struct kobject *kobj,
231 struct kobj_attribute *ka, char *buf)
232{
233 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
234 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
235 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
236}
237BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
238
239static ssize_t global_rsv_reserved_show(struct kobject *kobj,
240 struct kobj_attribute *a, char *buf)
241{
242 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
243 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
244 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
245}
246BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
247
248#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
249#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
250
251static ssize_t raid_bytes_show(struct kobject *kobj,
252 struct kobj_attribute *attr, char *buf);
253BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
254BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
255
256static ssize_t raid_bytes_show(struct kobject *kobj,
257 struct kobj_attribute *attr, char *buf)
258
259{
260 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
261 struct btrfs_block_group_cache *block_group;
262 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
263 u64 val = 0;
264
265 down_read(&sinfo->groups_sem);
266 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
267 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
268 val += block_group->key.offset;
269 else
270 val += btrfs_block_group_used(&block_group->item);
271 }
272 up_read(&sinfo->groups_sem);
273 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
274}
275
276static struct attribute *raid_attributes[] = {
277 BTRFS_ATTR_PTR(raid, total_bytes),
278 BTRFS_ATTR_PTR(raid, used_bytes),
279 NULL
280};
281
282static void release_raid_kobj(struct kobject *kobj)
283{
284 kfree(to_raid_kobj(kobj));
285}
286
287struct kobj_type btrfs_raid_ktype = {
288 .sysfs_ops = &kobj_sysfs_ops,
289 .release = release_raid_kobj,
290 .default_attrs = raid_attributes,
291};
292
293#define SPACE_INFO_ATTR(field) \
294static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
295 struct kobj_attribute *a, \
296 char *buf) \
297{ \
298 struct btrfs_space_info *sinfo = to_space_info(kobj); \
299 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
300} \
301BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
302
303static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
304 struct kobj_attribute *a,
305 char *buf)
306{
307 struct btrfs_space_info *sinfo = to_space_info(kobj);
308 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
309 return snprintf(buf, PAGE_SIZE, "%lld\n", val);
310}
311
312SPACE_INFO_ATTR(flags);
313SPACE_INFO_ATTR(total_bytes);
314SPACE_INFO_ATTR(bytes_used);
315SPACE_INFO_ATTR(bytes_pinned);
316SPACE_INFO_ATTR(bytes_reserved);
317SPACE_INFO_ATTR(bytes_may_use);
318SPACE_INFO_ATTR(bytes_readonly);
319SPACE_INFO_ATTR(disk_used);
320SPACE_INFO_ATTR(disk_total);
321BTRFS_ATTR(space_info, total_bytes_pinned,
322 btrfs_space_info_show_total_bytes_pinned);
323
324static struct attribute *space_info_attrs[] = {
325 BTRFS_ATTR_PTR(space_info, flags),
326 BTRFS_ATTR_PTR(space_info, total_bytes),
327 BTRFS_ATTR_PTR(space_info, bytes_used),
328 BTRFS_ATTR_PTR(space_info, bytes_pinned),
329 BTRFS_ATTR_PTR(space_info, bytes_reserved),
330 BTRFS_ATTR_PTR(space_info, bytes_may_use),
331 BTRFS_ATTR_PTR(space_info, bytes_readonly),
332 BTRFS_ATTR_PTR(space_info, disk_used),
333 BTRFS_ATTR_PTR(space_info, disk_total),
334 BTRFS_ATTR_PTR(space_info, total_bytes_pinned),
335 NULL,
336};
337
338static void space_info_release(struct kobject *kobj)
339{
340 struct btrfs_space_info *sinfo = to_space_info(kobj);
341 percpu_counter_destroy(&sinfo->total_bytes_pinned);
342 kfree(sinfo);
343}
344
345struct kobj_type space_info_ktype = {
346 .sysfs_ops = &kobj_sysfs_ops,
347 .release = space_info_release,
348 .default_attrs = space_info_attrs,
349};
350
351static const struct attribute *allocation_attrs[] = {
352 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
353 BTRFS_ATTR_PTR(allocation, global_rsv_size),
354 NULL,
355};
356
357static ssize_t btrfs_label_show(struct kobject *kobj,
358 struct kobj_attribute *a, char *buf)
359{
360 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
361 char *label = fs_info->super_copy->label;
362 ssize_t ret;
363
364 spin_lock(&fs_info->super_lock);
365 ret = snprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
366 spin_unlock(&fs_info->super_lock);
367
368 return ret;
369}
370
371static ssize_t btrfs_label_store(struct kobject *kobj,
372 struct kobj_attribute *a,
373 const char *buf, size_t len)
374{
375 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
376 size_t p_len;
377
378 if (!fs_info)
379 return -EPERM;
380
381 if (sb_rdonly(fs_info->sb))
382 return -EROFS;
383
384 /*
385 * p_len is the len until the first occurrence of either
386 * '\n' or '\0'
387 */
388 p_len = strcspn(buf, "\n");
389
390 if (p_len >= BTRFS_LABEL_SIZE)
391 return -EINVAL;
392
393 spin_lock(&fs_info->super_lock);
394 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
395 memcpy(fs_info->super_copy->label, buf, p_len);
396 spin_unlock(&fs_info->super_lock);
397
398 /*
399 * We don't want to do full transaction commit from inside sysfs
400 */
401 btrfs_set_pending(fs_info, COMMIT);
402 wake_up_process(fs_info->transaction_kthread);
403
404 return len;
405}
406BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
407
408static ssize_t btrfs_nodesize_show(struct kobject *kobj,
409 struct kobj_attribute *a, char *buf)
410{
411 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
412
413 return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
414}
415
416BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
417
418static ssize_t btrfs_sectorsize_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",
424 fs_info->super_copy->sectorsize);
425}
426
427BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
428
429static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
430 struct kobj_attribute *a, char *buf)
431{
432 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
433
434 return snprintf(buf, PAGE_SIZE, "%u\n",
435 fs_info->super_copy->sectorsize);
436}
437
438BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
439
440static ssize_t quota_override_show(struct kobject *kobj,
441 struct kobj_attribute *a, char *buf)
442{
443 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
444 int quota_override;
445
446 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
447 return snprintf(buf, PAGE_SIZE, "%d\n", quota_override);
448}
449
450static ssize_t quota_override_store(struct kobject *kobj,
451 struct kobj_attribute *a,
452 const char *buf, size_t len)
453{
454 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
455 unsigned long knob;
456 int err;
457
458 if (!fs_info)
459 return -EPERM;
460
461 if (!capable(CAP_SYS_RESOURCE))
462 return -EPERM;
463
464 err = kstrtoul(buf, 10, &knob);
465 if (err)
466 return err;
467 if (knob > 1)
468 return -EINVAL;
469
470 if (knob)
471 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
472 else
473 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
474
475 return len;
476}
477
478BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
479
480static const struct attribute *btrfs_attrs[] = {
481 BTRFS_ATTR_PTR(, label),
482 BTRFS_ATTR_PTR(, nodesize),
483 BTRFS_ATTR_PTR(, sectorsize),
484 BTRFS_ATTR_PTR(, clone_alignment),
485 BTRFS_ATTR_PTR(, quota_override),
486 NULL,
487};
488
489static void btrfs_release_fsid_kobj(struct kobject *kobj)
490{
491 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
492
493 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
494 complete(&fs_devs->kobj_unregister);
495}
496
497static struct kobj_type btrfs_ktype = {
498 .sysfs_ops = &kobj_sysfs_ops,
499 .release = btrfs_release_fsid_kobj,
500};
501
502static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
503{
504 if (kobj->ktype != &btrfs_ktype)
505 return NULL;
506 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
507}
508
509static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
510{
511 if (kobj->ktype != &btrfs_ktype)
512 return NULL;
513 return to_fs_devs(kobj)->fs_info;
514}
515
516#define NUM_FEATURE_BITS 64
517static char btrfs_unknown_feature_names[3][NUM_FEATURE_BITS][13];
518static struct btrfs_feature_attr btrfs_feature_attrs[3][NUM_FEATURE_BITS];
519
520static const u64 supported_feature_masks[3] = {
521 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
522 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
523 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
524};
525
526static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
527{
528 int set;
529
530 for (set = 0; set < FEAT_MAX; set++) {
531 int i;
532 struct attribute *attrs[2];
533 struct attribute_group agroup = {
534 .name = "features",
535 .attrs = attrs,
536 };
537 u64 features = get_features(fs_info, set);
538 features &= ~supported_feature_masks[set];
539
540 if (!features)
541 continue;
542
543 attrs[1] = NULL;
544 for (i = 0; i < NUM_FEATURE_BITS; i++) {
545 struct btrfs_feature_attr *fa;
546
547 if (!(features & (1ULL << i)))
548 continue;
549
550 fa = &btrfs_feature_attrs[set][i];
551 attrs[0] = &fa->kobj_attr.attr;
552 if (add) {
553 int ret;
554 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
555 &agroup);
556 if (ret)
557 return ret;
558 } else
559 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
560 &agroup);
561 }
562
563 }
564 return 0;
565}
566
567static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
568{
569 if (fs_devs->device_dir_kobj) {
570 kobject_del(fs_devs->device_dir_kobj);
571 kobject_put(fs_devs->device_dir_kobj);
572 fs_devs->device_dir_kobj = NULL;
573 }
574
575 if (fs_devs->fsid_kobj.state_initialized) {
576 kobject_del(&fs_devs->fsid_kobj);
577 kobject_put(&fs_devs->fsid_kobj);
578 wait_for_completion(&fs_devs->kobj_unregister);
579 }
580}
581
582/* when fs_devs is NULL it will remove all fsid kobject */
583void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
584{
585 struct list_head *fs_uuids = btrfs_get_fs_uuids();
586
587 if (fs_devs) {
588 __btrfs_sysfs_remove_fsid(fs_devs);
589 return;
590 }
591
592 list_for_each_entry(fs_devs, fs_uuids, list) {
593 __btrfs_sysfs_remove_fsid(fs_devs);
594 }
595}
596
597void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
598{
599 btrfs_reset_fs_info_ptr(fs_info);
600
601 if (fs_info->space_info_kobj) {
602 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
603 kobject_del(fs_info->space_info_kobj);
604 kobject_put(fs_info->space_info_kobj);
605 }
606 addrm_unknown_feature_attrs(fs_info, false);
607 sysfs_remove_group(&fs_info->fs_devices->fsid_kobj, &btrfs_feature_attr_group);
608 sysfs_remove_files(&fs_info->fs_devices->fsid_kobj, btrfs_attrs);
609 btrfs_sysfs_rm_device_link(fs_info->fs_devices, NULL);
610}
611
612const char * const btrfs_feature_set_names[3] = {
613 [FEAT_COMPAT] = "compat",
614 [FEAT_COMPAT_RO] = "compat_ro",
615 [FEAT_INCOMPAT] = "incompat",
616};
617
618char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
619{
620 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
621 int len = 0;
622 int i;
623 char *str;
624
625 str = kmalloc(bufsize, GFP_KERNEL);
626 if (!str)
627 return str;
628
629 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
630 const char *name;
631
632 if (!(flags & (1ULL << i)))
633 continue;
634
635 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
636 len += snprintf(str + len, bufsize - len, "%s%s",
637 len ? "," : "", name);
638 }
639
640 return str;
641}
642
643static void init_feature_attrs(void)
644{
645 struct btrfs_feature_attr *fa;
646 int set, i;
647
648 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
649 ARRAY_SIZE(btrfs_feature_attrs));
650 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
651 ARRAY_SIZE(btrfs_feature_attrs[0]));
652
653 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
654 memset(btrfs_unknown_feature_names, 0,
655 sizeof(btrfs_unknown_feature_names));
656
657 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
658 struct btrfs_feature_attr *sfa;
659 struct attribute *a = btrfs_supported_feature_attrs[i];
660 int bit;
661 sfa = attr_to_btrfs_feature_attr(a);
662 bit = ilog2(sfa->feature_bit);
663 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
664
665 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
666 }
667
668 for (set = 0; set < FEAT_MAX; set++) {
669 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
670 char *name = btrfs_unknown_feature_names[set][i];
671 fa = &btrfs_feature_attrs[set][i];
672
673 if (fa->kobj_attr.attr.name)
674 continue;
675
676 snprintf(name, 13, "%s:%u",
677 btrfs_feature_set_names[set], i);
678
679 fa->kobj_attr.attr.name = name;
680 fa->kobj_attr.attr.mode = S_IRUGO;
681 fa->feature_set = set;
682 fa->feature_bit = 1ULL << i;
683 }
684 }
685}
686
687/* when one_device is NULL, it removes all device links */
688
689int btrfs_sysfs_rm_device_link(struct btrfs_fs_devices *fs_devices,
690 struct btrfs_device *one_device)
691{
692 struct hd_struct *disk;
693 struct kobject *disk_kobj;
694
695 if (!fs_devices->device_dir_kobj)
696 return -EINVAL;
697
698 if (one_device && one_device->bdev) {
699 disk = one_device->bdev->bd_part;
700 disk_kobj = &part_to_dev(disk)->kobj;
701
702 sysfs_remove_link(fs_devices->device_dir_kobj,
703 disk_kobj->name);
704 }
705
706 if (one_device)
707 return 0;
708
709 list_for_each_entry(one_device,
710 &fs_devices->devices, dev_list) {
711 if (!one_device->bdev)
712 continue;
713 disk = one_device->bdev->bd_part;
714 disk_kobj = &part_to_dev(disk)->kobj;
715
716 sysfs_remove_link(fs_devices->device_dir_kobj,
717 disk_kobj->name);
718 }
719
720 return 0;
721}
722
723int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs)
724{
725 if (!fs_devs->device_dir_kobj)
726 fs_devs->device_dir_kobj = kobject_create_and_add("devices",
727 &fs_devs->fsid_kobj);
728
729 if (!fs_devs->device_dir_kobj)
730 return -ENOMEM;
731
732 return 0;
733}
734
735int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices,
736 struct btrfs_device *one_device)
737{
738 int error = 0;
739 struct btrfs_device *dev;
740
741 list_for_each_entry(dev, &fs_devices->devices, dev_list) {
742 struct hd_struct *disk;
743 struct kobject *disk_kobj;
744
745 if (!dev->bdev)
746 continue;
747
748 if (one_device && one_device != dev)
749 continue;
750
751 disk = dev->bdev->bd_part;
752 disk_kobj = &part_to_dev(disk)->kobj;
753
754 error = sysfs_create_link(fs_devices->device_dir_kobj,
755 disk_kobj, disk_kobj->name);
756 if (error)
757 break;
758 }
759
760 return error;
761}
762
763/* /sys/fs/btrfs/ entry */
764static struct kset *btrfs_kset;
765
766/* /sys/kernel/debug/btrfs */
767static struct dentry *btrfs_debugfs_root_dentry;
768
769/* Debugging tunables and exported data */
770u64 btrfs_debugfs_test;
771
772/*
773 * Can be called by the device discovery thread.
774 * And parent can be specified for seed device
775 */
776int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs,
777 struct kobject *parent)
778{
779 int error;
780
781 init_completion(&fs_devs->kobj_unregister);
782 fs_devs->fsid_kobj.kset = btrfs_kset;
783 error = kobject_init_and_add(&fs_devs->fsid_kobj,
784 &btrfs_ktype, parent, "%pU", fs_devs->fsid);
785 return error;
786}
787
788int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
789{
790 int error;
791 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
792 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
793
794 btrfs_set_fs_info_ptr(fs_info);
795
796 error = btrfs_sysfs_add_device_link(fs_devs, NULL);
797 if (error)
798 return error;
799
800 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
801 if (error) {
802 btrfs_sysfs_rm_device_link(fs_devs, NULL);
803 return error;
804 }
805
806 error = sysfs_create_group(fsid_kobj,
807 &btrfs_feature_attr_group);
808 if (error)
809 goto failure;
810
811 error = addrm_unknown_feature_attrs(fs_info, true);
812 if (error)
813 goto failure;
814
815 fs_info->space_info_kobj = kobject_create_and_add("allocation",
816 fsid_kobj);
817 if (!fs_info->space_info_kobj) {
818 error = -ENOMEM;
819 goto failure;
820 }
821
822 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
823 if (error)
824 goto failure;
825
826 return 0;
827failure:
828 btrfs_sysfs_remove_mounted(fs_info);
829 return error;
830}
831
832
833/*
834 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
835 * values in superblock. Call after any changes to incompat/compat_ro flags
836 */
837void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
838 u64 bit, enum btrfs_feature_set set)
839{
840 struct btrfs_fs_devices *fs_devs;
841 struct kobject *fsid_kobj;
842 u64 features;
843 int ret;
844
845 if (!fs_info)
846 return;
847
848 features = get_features(fs_info, set);
849 ASSERT(bit & supported_feature_masks[set]);
850
851 fs_devs = fs_info->fs_devices;
852 fsid_kobj = &fs_devs->fsid_kobj;
853
854 if (!fsid_kobj->state_initialized)
855 return;
856
857 /*
858 * FIXME: this is too heavy to update just one value, ideally we'd like
859 * to use sysfs_update_group but some refactoring is needed first.
860 */
861 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
862 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
863}
864
865static int btrfs_init_debugfs(void)
866{
867#ifdef CONFIG_DEBUG_FS
868 btrfs_debugfs_root_dentry = debugfs_create_dir("btrfs", NULL);
869 if (!btrfs_debugfs_root_dentry)
870 return -ENOMEM;
871
872 /*
873 * Example code, how to export data through debugfs.
874 *
875 * file: /sys/kernel/debug/btrfs/test
876 * contents of: btrfs_debugfs_test
877 */
878#ifdef CONFIG_BTRFS_DEBUG
879 debugfs_create_u64("test", S_IRUGO | S_IWUSR, btrfs_debugfs_root_dentry,
880 &btrfs_debugfs_test);
881#endif
882
883#endif
884 return 0;
885}
886
887int __init btrfs_init_sysfs(void)
888{
889 int ret;
890
891 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
892 if (!btrfs_kset)
893 return -ENOMEM;
894
895 ret = btrfs_init_debugfs();
896 if (ret)
897 goto out1;
898
899 init_feature_attrs();
900 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
901 if (ret)
902 goto out2;
903
904 return 0;
905out2:
906 debugfs_remove_recursive(btrfs_debugfs_root_dentry);
907out1:
908 kset_unregister(btrfs_kset);
909
910 return ret;
911}
912
913void __cold btrfs_exit_sysfs(void)
914{
915 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
916 kset_unregister(btrfs_kset);
917 debugfs_remove_recursive(btrfs_debugfs_root_dentry);
918}
919