]> git.proxmox.com Git - mirror_ubuntu-hirsute-kernel.git/blob - fs/btrfs/sysfs.c
projects / mirror_ubuntu-hirsute-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
mtd: rawnand: marvell: add missing clk_disable_unprepare() on error in marvell_nfc_re...
[mirror_ubuntu-hirsute-kernel.git] / fs / btrfs / sysfs.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/sched.h>
7 #include <linux/sched/mm.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/bug.h>
12 #include <crypto/hash.h>
13
14 #include "ctree.h"
15 #include "discard.h"
16 #include "disk-io.h"
17 #include "send.h"
18 #include "transaction.h"
19 #include "sysfs.h"
20 #include "volumes.h"
21 #include "space-info.h"
22 #include "block-group.h"
23 #include "qgroup.h"
24
25 struct btrfs_feature_attr {
26 struct kobj_attribute kobj_attr;
27 enum btrfs_feature_set feature_set;
28 u64 feature_bit;
29 };
30
31 /* For raid type sysfs entries */
32 struct raid_kobject {
33 u64 flags;
34 struct kobject kobj;
35 };
36
37 #define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
38 { \
39 .attr = { .name = __stringify(_name), .mode = _mode }, \
40 .show = _show, \
41 .store = _store, \
42 }
43
44 #define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
45 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
46 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
47
48 #define BTRFS_ATTR(_prefix, _name, _show) \
49 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
50 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
51
52 #define BTRFS_ATTR_PTR(_prefix, _name) \
53 (&btrfs_attr_##_prefix##_##_name.attr)
54
55 #define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
56 static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
57 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
58 btrfs_feature_attr_show, \
59 btrfs_feature_attr_store), \
60 .feature_set = _feature_set, \
61 .feature_bit = _feature_prefix ##_## _feature_bit, \
62 }
63 #define BTRFS_FEAT_ATTR_PTR(_name) \
64 (&btrfs_attr_features_##_name.kobj_attr.attr)
65
66 #define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
67 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
68 #define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
69 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
70 #define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
71 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
72
73 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
74 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
75
76 static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
77 {
78 return container_of(a, struct btrfs_feature_attr, kobj_attr);
79 }
80
81 static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
82 {
83 return container_of(attr, struct kobj_attribute, attr);
84 }
85
86 static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
87 struct attribute *attr)
88 {
89 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
90 }
91
92 static u64 get_features(struct btrfs_fs_info *fs_info,
93 enum btrfs_feature_set set)
94 {
95 struct btrfs_super_block *disk_super = fs_info->super_copy;
96 if (set == FEAT_COMPAT)
97 return btrfs_super_compat_flags(disk_super);
98 else if (set == FEAT_COMPAT_RO)
99 return btrfs_super_compat_ro_flags(disk_super);
100 else
101 return btrfs_super_incompat_flags(disk_super);
102 }
103
104 static void set_features(struct btrfs_fs_info *fs_info,
105 enum btrfs_feature_set set, u64 features)
106 {
107 struct btrfs_super_block *disk_super = fs_info->super_copy;
108 if (set == FEAT_COMPAT)
109 btrfs_set_super_compat_flags(disk_super, features);
110 else if (set == FEAT_COMPAT_RO)
111 btrfs_set_super_compat_ro_flags(disk_super, features);
112 else
113 btrfs_set_super_incompat_flags(disk_super, features);
114 }
115
116 static int can_modify_feature(struct btrfs_feature_attr *fa)
117 {
118 int val = 0;
119 u64 set, clear;
120 switch (fa->feature_set) {
121 case FEAT_COMPAT:
122 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
123 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
124 break;
125 case FEAT_COMPAT_RO:
126 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
127 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
128 break;
129 case FEAT_INCOMPAT:
130 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
131 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
132 break;
133 default:
134 pr_warn("btrfs: sysfs: unknown feature set %d\n",
135 fa->feature_set);
136 return 0;
137 }
138
139 if (set & fa->feature_bit)
140 val |= 1;
141 if (clear & fa->feature_bit)
142 val |= 2;
143
144 return val;
145 }
146
147 static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
148 struct kobj_attribute *a, char *buf)
149 {
150 int val = 0;
151 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
152 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
153 if (fs_info) {
154 u64 features = get_features(fs_info, fa->feature_set);
155 if (features & fa->feature_bit)
156 val = 1;
157 } else
158 val = can_modify_feature(fa);
159
160 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
161 }
162
163 static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
164 struct kobj_attribute *a,
165 const char *buf, size_t count)
166 {
167 struct btrfs_fs_info *fs_info;
168 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
169 u64 features, set, clear;
170 unsigned long val;
171 int ret;
172
173 fs_info = to_fs_info(kobj);
174 if (!fs_info)
175 return -EPERM;
176
177 if (sb_rdonly(fs_info->sb))
178 return -EROFS;
179
180 ret = kstrtoul(skip_spaces(buf), 0, &val);
181 if (ret)
182 return ret;
183
184 if (fa->feature_set == FEAT_COMPAT) {
185 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
186 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
187 } else if (fa->feature_set == FEAT_COMPAT_RO) {
188 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
189 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
190 } else {
191 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
192 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
193 }
194
195 features = get_features(fs_info, fa->feature_set);
196
197 /* Nothing to do */
198 if ((val && (features & fa->feature_bit)) ||
199 (!val && !(features & fa->feature_bit)))
200 return count;
201
202 if ((val && !(set & fa->feature_bit)) ||
203 (!val && !(clear & fa->feature_bit))) {
204 btrfs_info(fs_info,
205 "%sabling feature %s on mounted fs is not supported.",
206 val ? "En" : "Dis", fa->kobj_attr.attr.name);
207 return -EPERM;
208 }
209
210 btrfs_info(fs_info, "%s %s feature flag",
211 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
212
213 spin_lock(&fs_info->super_lock);
214 features = get_features(fs_info, fa->feature_set);
215 if (val)
216 features |= fa->feature_bit;
217 else
218 features &= ~fa->feature_bit;
219 set_features(fs_info, fa->feature_set, features);
220 spin_unlock(&fs_info->super_lock);
221
222 /*
223 * We don't want to do full transaction commit from inside sysfs
224 */
225 btrfs_set_pending(fs_info, COMMIT);
226 wake_up_process(fs_info->transaction_kthread);
227
228 return count;
229 }
230
231 static umode_t btrfs_feature_visible(struct kobject *kobj,
232 struct attribute *attr, int unused)
233 {
234 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
235 umode_t mode = attr->mode;
236
237 if (fs_info) {
238 struct btrfs_feature_attr *fa;
239 u64 features;
240
241 fa = attr_to_btrfs_feature_attr(attr);
242 features = get_features(fs_info, fa->feature_set);
243
244 if (can_modify_feature(fa))
245 mode |= S_IWUSR;
246 else if (!(features & fa->feature_bit))
247 mode = 0;
248 }
249
250 return mode;
251 }
252
253 BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
254 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
255 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
256 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
257 BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
258 BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
259 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
260 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
261 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
262 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
263 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
264 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
265 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
266 /* Remove once support for zoned allocation is feature complete */
267 #ifdef CONFIG_BTRFS_DEBUG
268 BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
269 #endif
270
271 static struct attribute *btrfs_supported_feature_attrs[] = {
272 BTRFS_FEAT_ATTR_PTR(mixed_backref),
273 BTRFS_FEAT_ATTR_PTR(default_subvol),
274 BTRFS_FEAT_ATTR_PTR(mixed_groups),
275 BTRFS_FEAT_ATTR_PTR(compress_lzo),
276 BTRFS_FEAT_ATTR_PTR(compress_zstd),
277 BTRFS_FEAT_ATTR_PTR(big_metadata),
278 BTRFS_FEAT_ATTR_PTR(extended_iref),
279 BTRFS_FEAT_ATTR_PTR(raid56),
280 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
281 BTRFS_FEAT_ATTR_PTR(no_holes),
282 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
283 BTRFS_FEAT_ATTR_PTR(free_space_tree),
284 BTRFS_FEAT_ATTR_PTR(raid1c34),
285 #ifdef CONFIG_BTRFS_DEBUG
286 BTRFS_FEAT_ATTR_PTR(zoned),
287 #endif
288 NULL
289 };
290
291 /*
292 * Features which depend on feature bits and may differ between each fs.
293 *
294 * /sys/fs/btrfs/features lists all available features of this kernel while
295 * /sys/fs/btrfs/UUID/features shows features of the fs which are enabled or
296 * can be changed online.
297 */
298 static const struct attribute_group btrfs_feature_attr_group = {
299 .name = "features",
300 .is_visible = btrfs_feature_visible,
301 .attrs = btrfs_supported_feature_attrs,
302 };
303
304 static ssize_t rmdir_subvol_show(struct kobject *kobj,
305 struct kobj_attribute *ka, char *buf)
306 {
307 return scnprintf(buf, PAGE_SIZE, "0\n");
308 }
309 BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
310
311 static ssize_t supported_checksums_show(struct kobject *kobj,
312 struct kobj_attribute *a, char *buf)
313 {
314 ssize_t ret = 0;
315 int i;
316
317 for (i = 0; i < btrfs_get_num_csums(); i++) {
318 /*
319 * This "trick" only works as long as 'enum btrfs_csum_type' has
320 * no holes in it
321 */
322 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
323 (i == 0 ? "" : " "), btrfs_super_csum_name(i));
324
325 }
326
327 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
328 return ret;
329 }
330 BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
331
332 static ssize_t send_stream_version_show(struct kobject *kobj,
333 struct kobj_attribute *ka, char *buf)
334 {
335 return snprintf(buf, PAGE_SIZE, "%d\n", BTRFS_SEND_STREAM_VERSION);
336 }
337 BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
338
339 static const char *rescue_opts[] = {
340 "usebackuproot",
341 "nologreplay",
342 "ignorebadroots",
343 "ignoredatacsums",
344 "all",
345 };
346
347 static ssize_t supported_rescue_options_show(struct kobject *kobj,
348 struct kobj_attribute *a,
349 char *buf)
350 {
351 ssize_t ret = 0;
352 int i;
353
354 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
355 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
356 (i ? " " : ""), rescue_opts[i]);
357 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
358 return ret;
359 }
360 BTRFS_ATTR(static_feature, supported_rescue_options,
361 supported_rescue_options_show);
362
363 static struct attribute *btrfs_supported_static_feature_attrs[] = {
364 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
365 BTRFS_ATTR_PTR(static_feature, supported_checksums),
366 BTRFS_ATTR_PTR(static_feature, send_stream_version),
367 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
368 NULL
369 };
370
371 /*
372 * Features which only depend on kernel version.
373 *
374 * These are listed in /sys/fs/btrfs/features along with
375 * btrfs_feature_attr_group
376 */
377 static const struct attribute_group btrfs_static_feature_attr_group = {
378 .name = "features",
379 .attrs = btrfs_supported_static_feature_attrs,
380 };
381
382 #ifdef CONFIG_BTRFS_DEBUG
383
384 /*
385 * Discard statistics and tunables
386 */
387 #define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent)
388
389 static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
390 struct kobj_attribute *a,
391 char *buf)
392 {
393 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
394
395 return scnprintf(buf, PAGE_SIZE, "%lld\n",
396 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
397 }
398 BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
399
400 static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
401 struct kobj_attribute *a,
402 char *buf)
403 {
404 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
405
406 return scnprintf(buf, PAGE_SIZE, "%d\n",
407 atomic_read(&fs_info->discard_ctl.discardable_extents));
408 }
409 BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
410
411 static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
412 struct kobj_attribute *a,
413 char *buf)
414 {
415 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
416
417 return scnprintf(buf, PAGE_SIZE, "%llu\n",
418 fs_info->discard_ctl.discard_bitmap_bytes);
419 }
420 BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
421
422 static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
423 struct kobj_attribute *a,
424 char *buf)
425 {
426 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
427
428 return scnprintf(buf, PAGE_SIZE, "%lld\n",
429 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
430 }
431 BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
432
433 static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
434 struct kobj_attribute *a,
435 char *buf)
436 {
437 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
438
439 return scnprintf(buf, PAGE_SIZE, "%llu\n",
440 fs_info->discard_ctl.discard_extent_bytes);
441 }
442 BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
443
444 static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
445 struct kobj_attribute *a,
446 char *buf)
447 {
448 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
449
450 return scnprintf(buf, PAGE_SIZE, "%u\n",
451 READ_ONCE(fs_info->discard_ctl.iops_limit));
452 }
453
454 static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
455 struct kobj_attribute *a,
456 const char *buf, size_t len)
457 {
458 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
459 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
460 u32 iops_limit;
461 int ret;
462
463 ret = kstrtou32(buf, 10, &iops_limit);
464 if (ret)
465 return -EINVAL;
466
467 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
468 btrfs_discard_calc_delay(discard_ctl);
469 btrfs_discard_schedule_work(discard_ctl, true);
470 return len;
471 }
472 BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
473 btrfs_discard_iops_limit_store);
474
475 static ssize_t btrfs_discard_kbps_limit_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 scnprintf(buf, PAGE_SIZE, "%u\n",
482 READ_ONCE(fs_info->discard_ctl.kbps_limit));
483 }
484
485 static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
486 struct kobj_attribute *a,
487 const char *buf, size_t len)
488 {
489 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
490 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
491 u32 kbps_limit;
492 int ret;
493
494 ret = kstrtou32(buf, 10, &kbps_limit);
495 if (ret)
496 return -EINVAL;
497
498 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
499 btrfs_discard_schedule_work(discard_ctl, true);
500 return len;
501 }
502 BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
503 btrfs_discard_kbps_limit_store);
504
505 static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
506 struct kobj_attribute *a,
507 char *buf)
508 {
509 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
510
511 return scnprintf(buf, PAGE_SIZE, "%llu\n",
512 READ_ONCE(fs_info->discard_ctl.max_discard_size));
513 }
514
515 static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
516 struct kobj_attribute *a,
517 const char *buf, size_t len)
518 {
519 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
520 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
521 u64 max_discard_size;
522 int ret;
523
524 ret = kstrtou64(buf, 10, &max_discard_size);
525 if (ret)
526 return -EINVAL;
527
528 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
529
530 return len;
531 }
532 BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
533 btrfs_discard_max_discard_size_store);
534
535 static const struct attribute *discard_debug_attrs[] = {
536 BTRFS_ATTR_PTR(discard, discardable_bytes),
537 BTRFS_ATTR_PTR(discard, discardable_extents),
538 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
539 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
540 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
541 BTRFS_ATTR_PTR(discard, iops_limit),
542 BTRFS_ATTR_PTR(discard, kbps_limit),
543 BTRFS_ATTR_PTR(discard, max_discard_size),
544 NULL,
545 };
546
547 /*
548 * Runtime debugging exported via sysfs
549 *
550 * /sys/fs/btrfs/debug - applies to module or all filesystems
551 * /sys/fs/btrfs/UUID - applies only to the given filesystem
552 */
553 static const struct attribute *btrfs_debug_mount_attrs[] = {
554 NULL,
555 };
556
557 static struct attribute *btrfs_debug_feature_attrs[] = {
558 NULL
559 };
560
561 static const struct attribute_group btrfs_debug_feature_attr_group = {
562 .name = "debug",
563 .attrs = btrfs_debug_feature_attrs,
564 };
565
566 #endif
567
568 static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
569 {
570 u64 val;
571 if (lock)
572 spin_lock(lock);
573 val = *value_ptr;
574 if (lock)
575 spin_unlock(lock);
576 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
577 }
578
579 static ssize_t global_rsv_size_show(struct kobject *kobj,
580 struct kobj_attribute *ka, char *buf)
581 {
582 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
583 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
584 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
585 }
586 BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
587
588 static ssize_t global_rsv_reserved_show(struct kobject *kobj,
589 struct kobj_attribute *a, char *buf)
590 {
591 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
592 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
593 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
594 }
595 BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
596
597 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
598 #define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
599
600 static ssize_t raid_bytes_show(struct kobject *kobj,
601 struct kobj_attribute *attr, char *buf);
602 BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
603 BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
604
605 static ssize_t raid_bytes_show(struct kobject *kobj,
606 struct kobj_attribute *attr, char *buf)
607
608 {
609 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
610 struct btrfs_block_group *block_group;
611 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
612 u64 val = 0;
613
614 down_read(&sinfo->groups_sem);
615 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
616 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
617 val += block_group->length;
618 else
619 val += block_group->used;
620 }
621 up_read(&sinfo->groups_sem);
622 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
623 }
624
625 static struct attribute *raid_attrs[] = {
626 BTRFS_ATTR_PTR(raid, total_bytes),
627 BTRFS_ATTR_PTR(raid, used_bytes),
628 NULL
629 };
630 ATTRIBUTE_GROUPS(raid);
631
632 static void release_raid_kobj(struct kobject *kobj)
633 {
634 kfree(to_raid_kobj(kobj));
635 }
636
637 static struct kobj_type btrfs_raid_ktype = {
638 .sysfs_ops = &kobj_sysfs_ops,
639 .release = release_raid_kobj,
640 .default_groups = raid_groups,
641 };
642
643 #define SPACE_INFO_ATTR(field) \
644 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
645 struct kobj_attribute *a, \
646 char *buf) \
647 { \
648 struct btrfs_space_info *sinfo = to_space_info(kobj); \
649 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
650 } \
651 BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
652
653 static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
654 struct kobj_attribute *a,
655 char *buf)
656 {
657 struct btrfs_space_info *sinfo = to_space_info(kobj);
658 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
659 return scnprintf(buf, PAGE_SIZE, "%lld\n", val);
660 }
661
662 SPACE_INFO_ATTR(flags);
663 SPACE_INFO_ATTR(total_bytes);
664 SPACE_INFO_ATTR(bytes_used);
665 SPACE_INFO_ATTR(bytes_pinned);
666 SPACE_INFO_ATTR(bytes_reserved);
667 SPACE_INFO_ATTR(bytes_may_use);
668 SPACE_INFO_ATTR(bytes_readonly);
669 SPACE_INFO_ATTR(disk_used);
670 SPACE_INFO_ATTR(disk_total);
671 BTRFS_ATTR(space_info, total_bytes_pinned,
672 btrfs_space_info_show_total_bytes_pinned);
673
674 static struct attribute *space_info_attrs[] = {
675 BTRFS_ATTR_PTR(space_info, flags),
676 BTRFS_ATTR_PTR(space_info, total_bytes),
677 BTRFS_ATTR_PTR(space_info, bytes_used),
678 BTRFS_ATTR_PTR(space_info, bytes_pinned),
679 BTRFS_ATTR_PTR(space_info, bytes_reserved),
680 BTRFS_ATTR_PTR(space_info, bytes_may_use),
681 BTRFS_ATTR_PTR(space_info, bytes_readonly),
682 BTRFS_ATTR_PTR(space_info, disk_used),
683 BTRFS_ATTR_PTR(space_info, disk_total),
684 BTRFS_ATTR_PTR(space_info, total_bytes_pinned),
685 NULL,
686 };
687 ATTRIBUTE_GROUPS(space_info);
688
689 static void space_info_release(struct kobject *kobj)
690 {
691 struct btrfs_space_info *sinfo = to_space_info(kobj);
692 percpu_counter_destroy(&sinfo->total_bytes_pinned);
693 kfree(sinfo);
694 }
695
696 static struct kobj_type space_info_ktype = {
697 .sysfs_ops = &kobj_sysfs_ops,
698 .release = space_info_release,
699 .default_groups = space_info_groups,
700 };
701
702 static const struct attribute *allocation_attrs[] = {
703 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
704 BTRFS_ATTR_PTR(allocation, global_rsv_size),
705 NULL,
706 };
707
708 static ssize_t btrfs_label_show(struct kobject *kobj,
709 struct kobj_attribute *a, char *buf)
710 {
711 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
712 char *label = fs_info->super_copy->label;
713 ssize_t ret;
714
715 spin_lock(&fs_info->super_lock);
716 ret = scnprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
717 spin_unlock(&fs_info->super_lock);
718
719 return ret;
720 }
721
722 static ssize_t btrfs_label_store(struct kobject *kobj,
723 struct kobj_attribute *a,
724 const char *buf, size_t len)
725 {
726 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
727 size_t p_len;
728
729 if (!fs_info)
730 return -EPERM;
731
732 if (sb_rdonly(fs_info->sb))
733 return -EROFS;
734
735 /*
736 * p_len is the len until the first occurrence of either
737 * '\n' or '\0'
738 */
739 p_len = strcspn(buf, "\n");
740
741 if (p_len >= BTRFS_LABEL_SIZE)
742 return -EINVAL;
743
744 spin_lock(&fs_info->super_lock);
745 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
746 memcpy(fs_info->super_copy->label, buf, p_len);
747 spin_unlock(&fs_info->super_lock);
748
749 /*
750 * We don't want to do full transaction commit from inside sysfs
751 */
752 btrfs_set_pending(fs_info, COMMIT);
753 wake_up_process(fs_info->transaction_kthread);
754
755 return len;
756 }
757 BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
758
759 static ssize_t btrfs_nodesize_show(struct kobject *kobj,
760 struct kobj_attribute *a, char *buf)
761 {
762 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
763
764 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
765 }
766
767 BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
768
769 static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
770 struct kobj_attribute *a, char *buf)
771 {
772 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
773
774 return scnprintf(buf, PAGE_SIZE, "%u\n",
775 fs_info->super_copy->sectorsize);
776 }
777
778 BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
779
780 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
781 struct kobj_attribute *a, char *buf)
782 {
783 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
784
785 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
786 }
787
788 BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
789
790 static ssize_t quota_override_show(struct kobject *kobj,
791 struct kobj_attribute *a, char *buf)
792 {
793 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
794 int quota_override;
795
796 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
797 return scnprintf(buf, PAGE_SIZE, "%d\n", quota_override);
798 }
799
800 static ssize_t quota_override_store(struct kobject *kobj,
801 struct kobj_attribute *a,
802 const char *buf, size_t len)
803 {
804 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
805 unsigned long knob;
806 int err;
807
808 if (!fs_info)
809 return -EPERM;
810
811 if (!capable(CAP_SYS_RESOURCE))
812 return -EPERM;
813
814 err = kstrtoul(buf, 10, &knob);
815 if (err)
816 return err;
817 if (knob > 1)
818 return -EINVAL;
819
820 if (knob)
821 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
822 else
823 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
824
825 return len;
826 }
827
828 BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
829
830 static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
831 struct kobj_attribute *a, char *buf)
832 {
833 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
834
835 return scnprintf(buf, PAGE_SIZE, "%pU\n",
836 fs_info->fs_devices->metadata_uuid);
837 }
838
839 BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
840
841 static ssize_t btrfs_checksum_show(struct kobject *kobj,
842 struct kobj_attribute *a, char *buf)
843 {
844 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
845 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
846
847 return scnprintf(buf, PAGE_SIZE, "%s (%s)\n",
848 btrfs_super_csum_name(csum_type),
849 crypto_shash_driver_name(fs_info->csum_shash));
850 }
851
852 BTRFS_ATTR(, checksum, btrfs_checksum_show);
853
854 static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
855 struct kobj_attribute *a, char *buf)
856 {
857 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
858 const char *str;
859
860 switch (READ_ONCE(fs_info->exclusive_operation)) {
861 case BTRFS_EXCLOP_NONE:
862 str = "none\n";
863 break;
864 case BTRFS_EXCLOP_BALANCE:
865 str = "balance\n";
866 break;
867 case BTRFS_EXCLOP_DEV_ADD:
868 str = "device add\n";
869 break;
870 case BTRFS_EXCLOP_DEV_REMOVE:
871 str = "device remove\n";
872 break;
873 case BTRFS_EXCLOP_DEV_REPLACE:
874 str = "device replace\n";
875 break;
876 case BTRFS_EXCLOP_RESIZE:
877 str = "resize\n";
878 break;
879 case BTRFS_EXCLOP_SWAP_ACTIVATE:
880 str = "swap activate\n";
881 break;
882 default:
883 str = "UNKNOWN\n";
884 break;
885 }
886 return scnprintf(buf, PAGE_SIZE, "%s", str);
887 }
888 BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
889
890 static ssize_t btrfs_generation_show(struct kobject *kobj,
891 struct kobj_attribute *a, char *buf)
892 {
893 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
894
895 return scnprintf(buf, PAGE_SIZE, "%llu\n", fs_info->generation);
896 }
897 BTRFS_ATTR(, generation, btrfs_generation_show);
898
899 /*
900 * Look for an exact string @string in @buffer with possible leading or
901 * trailing whitespace
902 */
903 static bool strmatch(const char *buffer, const char *string)
904 {
905 const size_t len = strlen(string);
906
907 /* Skip leading whitespace */
908 buffer = skip_spaces(buffer);
909
910 /* Match entire string, check if the rest is whitespace or empty */
911 if (strncmp(string, buffer, len) == 0 &&
912 strlen(skip_spaces(buffer + len)) == 0)
913 return true;
914
915 return false;
916 }
917
918 static const char * const btrfs_read_policy_name[] = { "pid" };
919
920 static ssize_t btrfs_read_policy_show(struct kobject *kobj,
921 struct kobj_attribute *a, char *buf)
922 {
923 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
924 ssize_t ret = 0;
925 int i;
926
927 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
928 if (fs_devices->read_policy == i)
929 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s[%s]",
930 (ret == 0 ? "" : " "),
931 btrfs_read_policy_name[i]);
932 else
933 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
934 (ret == 0 ? "" : " "),
935 btrfs_read_policy_name[i]);
936 }
937
938 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
939
940 return ret;
941 }
942
943 static ssize_t btrfs_read_policy_store(struct kobject *kobj,
944 struct kobj_attribute *a,
945 const char *buf, size_t len)
946 {
947 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
948 int i;
949
950 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
951 if (strmatch(buf, btrfs_read_policy_name[i])) {
952 if (i != fs_devices->read_policy) {
953 fs_devices->read_policy = i;
954 btrfs_info(fs_devices->fs_info,
955 "read policy set to '%s'",
956 btrfs_read_policy_name[i]);
957 }
958 return len;
959 }
960 }
961
962 return -EINVAL;
963 }
964 BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
965
966 static const struct attribute *btrfs_attrs[] = {
967 BTRFS_ATTR_PTR(, label),
968 BTRFS_ATTR_PTR(, nodesize),
969 BTRFS_ATTR_PTR(, sectorsize),
970 BTRFS_ATTR_PTR(, clone_alignment),
971 BTRFS_ATTR_PTR(, quota_override),
972 BTRFS_ATTR_PTR(, metadata_uuid),
973 BTRFS_ATTR_PTR(, checksum),
974 BTRFS_ATTR_PTR(, exclusive_operation),
975 BTRFS_ATTR_PTR(, generation),
976 BTRFS_ATTR_PTR(, read_policy),
977 NULL,
978 };
979
980 static void btrfs_release_fsid_kobj(struct kobject *kobj)
981 {
982 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
983
984 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
985 complete(&fs_devs->kobj_unregister);
986 }
987
988 static struct kobj_type btrfs_ktype = {
989 .sysfs_ops = &kobj_sysfs_ops,
990 .release = btrfs_release_fsid_kobj,
991 };
992
993 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
994 {
995 if (kobj->ktype != &btrfs_ktype)
996 return NULL;
997 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
998 }
999
1000 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1001 {
1002 if (kobj->ktype != &btrfs_ktype)
1003 return NULL;
1004 return to_fs_devs(kobj)->fs_info;
1005 }
1006
1007 #define NUM_FEATURE_BITS 64
1008 #define BTRFS_FEATURE_NAME_MAX 13
1009 static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1010 static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1011
1012 static const u64 supported_feature_masks[FEAT_MAX] = {
1013 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1014 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1015 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1016 };
1017
1018 static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1019 {
1020 int set;
1021
1022 for (set = 0; set < FEAT_MAX; set++) {
1023 int i;
1024 struct attribute *attrs[2];
1025 struct attribute_group agroup = {
1026 .name = "features",
1027 .attrs = attrs,
1028 };
1029 u64 features = get_features(fs_info, set);
1030 features &= ~supported_feature_masks[set];
1031
1032 if (!features)
1033 continue;
1034
1035 attrs[1] = NULL;
1036 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1037 struct btrfs_feature_attr *fa;
1038
1039 if (!(features & (1ULL << i)))
1040 continue;
1041
1042 fa = &btrfs_feature_attrs[set][i];
1043 attrs[0] = &fa->kobj_attr.attr;
1044 if (add) {
1045 int ret;
1046 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1047 &agroup);
1048 if (ret)
1049 return ret;
1050 } else
1051 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1052 &agroup);
1053 }
1054
1055 }
1056 return 0;
1057 }
1058
1059 static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1060 {
1061 if (fs_devs->devinfo_kobj) {
1062 kobject_del(fs_devs->devinfo_kobj);
1063 kobject_put(fs_devs->devinfo_kobj);
1064 fs_devs->devinfo_kobj = NULL;
1065 }
1066
1067 if (fs_devs->devices_kobj) {
1068 kobject_del(fs_devs->devices_kobj);
1069 kobject_put(fs_devs->devices_kobj);
1070 fs_devs->devices_kobj = NULL;
1071 }
1072
1073 if (fs_devs->fsid_kobj.state_initialized) {
1074 kobject_del(&fs_devs->fsid_kobj);
1075 kobject_put(&fs_devs->fsid_kobj);
1076 wait_for_completion(&fs_devs->kobj_unregister);
1077 }
1078 }
1079
1080 /* when fs_devs is NULL it will remove all fsid kobject */
1081 void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1082 {
1083 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1084
1085 if (fs_devs) {
1086 __btrfs_sysfs_remove_fsid(fs_devs);
1087 return;
1088 }
1089
1090 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1091 __btrfs_sysfs_remove_fsid(fs_devs);
1092 }
1093 }
1094
1095 static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1096 {
1097 struct btrfs_device *device;
1098 struct btrfs_fs_devices *seed;
1099
1100 list_for_each_entry(device, &fs_devices->devices, dev_list)
1101 btrfs_sysfs_remove_device(device);
1102
1103 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1104 list_for_each_entry(device, &seed->devices, dev_list)
1105 btrfs_sysfs_remove_device(device);
1106 }
1107 }
1108
1109 void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1110 {
1111 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1112
1113 sysfs_remove_link(fsid_kobj, "bdi");
1114
1115 if (fs_info->space_info_kobj) {
1116 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1117 kobject_del(fs_info->space_info_kobj);
1118 kobject_put(fs_info->space_info_kobj);
1119 }
1120 #ifdef CONFIG_BTRFS_DEBUG
1121 if (fs_info->discard_debug_kobj) {
1122 sysfs_remove_files(fs_info->discard_debug_kobj,
1123 discard_debug_attrs);
1124 kobject_del(fs_info->discard_debug_kobj);
1125 kobject_put(fs_info->discard_debug_kobj);
1126 }
1127 if (fs_info->debug_kobj) {
1128 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1129 kobject_del(fs_info->debug_kobj);
1130 kobject_put(fs_info->debug_kobj);
1131 }
1132 #endif
1133 addrm_unknown_feature_attrs(fs_info, false);
1134 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1135 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1136 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1137 }
1138
1139 static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1140 [FEAT_COMPAT] = "compat",
1141 [FEAT_COMPAT_RO] = "compat_ro",
1142 [FEAT_INCOMPAT] = "incompat",
1143 };
1144
1145 const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1146 {
1147 return btrfs_feature_set_names[set];
1148 }
1149
1150 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1151 {
1152 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1153 int len = 0;
1154 int i;
1155 char *str;
1156
1157 str = kmalloc(bufsize, GFP_KERNEL);
1158 if (!str)
1159 return str;
1160
1161 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1162 const char *name;
1163
1164 if (!(flags & (1ULL << i)))
1165 continue;
1166
1167 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1168 len += scnprintf(str + len, bufsize - len, "%s%s",
1169 len ? "," : "", name);
1170 }
1171
1172 return str;
1173 }
1174
1175 static void init_feature_attrs(void)
1176 {
1177 struct btrfs_feature_attr *fa;
1178 int set, i;
1179
1180 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
1181 ARRAY_SIZE(btrfs_feature_attrs));
1182 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
1183 ARRAY_SIZE(btrfs_feature_attrs[0]));
1184
1185 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1186 memset(btrfs_unknown_feature_names, 0,
1187 sizeof(btrfs_unknown_feature_names));
1188
1189 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1190 struct btrfs_feature_attr *sfa;
1191 struct attribute *a = btrfs_supported_feature_attrs[i];
1192 int bit;
1193 sfa = attr_to_btrfs_feature_attr(a);
1194 bit = ilog2(sfa->feature_bit);
1195 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1196
1197 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1198 }
1199
1200 for (set = 0; set < FEAT_MAX; set++) {
1201 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1202 char *name = btrfs_unknown_feature_names[set][i];
1203 fa = &btrfs_feature_attrs[set][i];
1204
1205 if (fa->kobj_attr.attr.name)
1206 continue;
1207
1208 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1209 btrfs_feature_set_names[set], i);
1210
1211 fa->kobj_attr.attr.name = name;
1212 fa->kobj_attr.attr.mode = S_IRUGO;
1213 fa->feature_set = set;
1214 fa->feature_bit = 1ULL << i;
1215 }
1216 }
1217 }
1218
1219 /*
1220 * Create a sysfs entry for a given block group type at path
1221 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1222 */
1223 void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1224 {
1225 struct btrfs_fs_info *fs_info = cache->fs_info;
1226 struct btrfs_space_info *space_info = cache->space_info;
1227 struct raid_kobject *rkobj;
1228 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1229 unsigned int nofs_flag;
1230 int ret;
1231
1232 /*
1233 * Setup a NOFS context because kobject_add(), deep in its call chain,
1234 * does GFP_KERNEL allocations, and we are often called in a context
1235 * where if reclaim is triggered we can deadlock (we are either holding
1236 * a transaction handle or some lock required for a transaction
1237 * commit).
1238 */
1239 nofs_flag = memalloc_nofs_save();
1240
1241 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1242 if (!rkobj) {
1243 memalloc_nofs_restore(nofs_flag);
1244 btrfs_warn(cache->fs_info,
1245 "couldn't alloc memory for raid level kobject");
1246 return;
1247 }
1248
1249 rkobj->flags = cache->flags;
1250 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1251
1252 /*
1253 * We call this either on mount, or if we've created a block group for a
1254 * new index type while running (i.e. when restriping). The running
1255 * case is tricky because we could race with other threads, so we need
1256 * to have this check to make sure we didn't already init the kobject.
1257 *
1258 * We don't have to protect on the free side because it only happens on
1259 * unmount.
1260 */
1261 spin_lock(&space_info->lock);
1262 if (space_info->block_group_kobjs[index]) {
1263 spin_unlock(&space_info->lock);
1264 kobject_put(&rkobj->kobj);
1265 return;
1266 } else {
1267 space_info->block_group_kobjs[index] = &rkobj->kobj;
1268 }
1269 spin_unlock(&space_info->lock);
1270
1271 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1272 btrfs_bg_type_to_raid_name(rkobj->flags));
1273 memalloc_nofs_restore(nofs_flag);
1274 if (ret) {
1275 spin_lock(&space_info->lock);
1276 space_info->block_group_kobjs[index] = NULL;
1277 spin_unlock(&space_info->lock);
1278 kobject_put(&rkobj->kobj);
1279 btrfs_warn(fs_info,
1280 "failed to add kobject for block cache, ignoring");
1281 return;
1282 }
1283 }
1284
1285 /*
1286 * Remove sysfs directories for all block group types of a given space info and
1287 * the space info as well
1288 */
1289 void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1290 {
1291 int i;
1292
1293 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1294 struct kobject *kobj;
1295
1296 kobj = space_info->block_group_kobjs[i];
1297 space_info->block_group_kobjs[i] = NULL;
1298 if (kobj) {
1299 kobject_del(kobj);
1300 kobject_put(kobj);
1301 }
1302 }
1303 kobject_del(&space_info->kobj);
1304 kobject_put(&space_info->kobj);
1305 }
1306
1307 static const char *alloc_name(u64 flags)
1308 {
1309 switch (flags) {
1310 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1311 return "mixed";
1312 case BTRFS_BLOCK_GROUP_METADATA:
1313 return "metadata";
1314 case BTRFS_BLOCK_GROUP_DATA:
1315 return "data";
1316 case BTRFS_BLOCK_GROUP_SYSTEM:
1317 return "system";
1318 default:
1319 WARN_ON(1);
1320 return "invalid-combination";
1321 }
1322 }
1323
1324 /*
1325 * Create a sysfs entry for a space info type at path
1326 * /sys/fs/btrfs/UUID/allocation/TYPE
1327 */
1328 int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1329 struct btrfs_space_info *space_info)
1330 {
1331 int ret;
1332
1333 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1334 fs_info->space_info_kobj, "%s",
1335 alloc_name(space_info->flags));
1336 if (ret) {
1337 kobject_put(&space_info->kobj);
1338 return ret;
1339 }
1340
1341 return 0;
1342 }
1343
1344 void btrfs_sysfs_remove_device(struct btrfs_device *device)
1345 {
1346 struct kobject *devices_kobj;
1347
1348 /*
1349 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1350 * fs_info::fs_devices.
1351 */
1352 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1353 ASSERT(devices_kobj);
1354
1355 if (device->bdev)
1356 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1357
1358 if (device->devid_kobj.state_initialized) {
1359 kobject_del(&device->devid_kobj);
1360 kobject_put(&device->devid_kobj);
1361 wait_for_completion(&device->kobj_unregister);
1362 }
1363 }
1364
1365 static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1366 struct kobj_attribute *a,
1367 char *buf)
1368 {
1369 int val;
1370 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1371 devid_kobj);
1372
1373 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1374
1375 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1376 }
1377 BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1378
1379 static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1380 struct kobj_attribute *a, char *buf)
1381 {
1382 int val;
1383 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1384 devid_kobj);
1385
1386 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1387
1388 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1389 }
1390 BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1391
1392 static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1393 struct kobj_attribute *a,
1394 char *buf)
1395 {
1396 int val;
1397 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1398 devid_kobj);
1399
1400 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1401
1402 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1403 }
1404 BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1405
1406 static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1407 struct kobj_attribute *a, char *buf)
1408 {
1409 int val;
1410 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1411 devid_kobj);
1412
1413 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1414
1415 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1416 }
1417 BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1418
1419 static struct attribute *devid_attrs[] = {
1420 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1421 BTRFS_ATTR_PTR(devid, missing),
1422 BTRFS_ATTR_PTR(devid, replace_target),
1423 BTRFS_ATTR_PTR(devid, writeable),
1424 NULL
1425 };
1426 ATTRIBUTE_GROUPS(devid);
1427
1428 static void btrfs_release_devid_kobj(struct kobject *kobj)
1429 {
1430 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1431 devid_kobj);
1432
1433 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1434 complete(&device->kobj_unregister);
1435 }
1436
1437 static struct kobj_type devid_ktype = {
1438 .sysfs_ops = &kobj_sysfs_ops,
1439 .default_groups = devid_groups,
1440 .release = btrfs_release_devid_kobj,
1441 };
1442
1443 int btrfs_sysfs_add_device(struct btrfs_device *device)
1444 {
1445 int ret;
1446 unsigned int nofs_flag;
1447 struct kobject *devices_kobj;
1448 struct kobject *devinfo_kobj;
1449
1450 /*
1451 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
1452 * for the seed fs_devices
1453 */
1454 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1455 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
1456 ASSERT(devices_kobj);
1457 ASSERT(devinfo_kobj);
1458
1459 nofs_flag = memalloc_nofs_save();
1460
1461 if (device->bdev) {
1462 struct kobject *disk_kobj = bdev_kobj(device->bdev);
1463
1464 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
1465 if (ret) {
1466 btrfs_warn(device->fs_info,
1467 "creating sysfs device link for devid %llu failed: %d",
1468 device->devid, ret);
1469 goto out;
1470 }
1471 }
1472
1473 init_completion(&device->kobj_unregister);
1474 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
1475 devinfo_kobj, "%llu", device->devid);
1476 if (ret) {
1477 kobject_put(&device->devid_kobj);
1478 btrfs_warn(device->fs_info,
1479 "devinfo init for devid %llu failed: %d",
1480 device->devid, ret);
1481 }
1482
1483 out:
1484 memalloc_nofs_restore(nofs_flag);
1485 return ret;
1486 }
1487
1488 static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
1489 {
1490 int ret;
1491 struct btrfs_device *device;
1492 struct btrfs_fs_devices *seed;
1493
1494 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1495 ret = btrfs_sysfs_add_device(device);
1496 if (ret)
1497 goto fail;
1498 }
1499
1500 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1501 list_for_each_entry(device, &seed->devices, dev_list) {
1502 ret = btrfs_sysfs_add_device(device);
1503 if (ret)
1504 goto fail;
1505 }
1506 }
1507
1508 return 0;
1509
1510 fail:
1511 btrfs_sysfs_remove_fs_devices(fs_devices);
1512 return ret;
1513 }
1514
1515 void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1516 {
1517 int ret;
1518
1519 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1520 if (ret)
1521 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1522 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1523 &disk_to_dev(bdev->bd_disk)->kobj);
1524 }
1525
1526 void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
1527
1528 {
1529 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1530
1531 /*
1532 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1533 * directory
1534 */
1535 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
1536 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1537 btrfs_warn(fs_devices->fs_info,
1538 "sysfs: failed to create fsid for sprout");
1539 }
1540
1541 void btrfs_sysfs_update_devid(struct btrfs_device *device)
1542 {
1543 char tmp[24];
1544
1545 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
1546
1547 if (kobject_rename(&device->devid_kobj, tmp))
1548 btrfs_warn(device->fs_devices->fs_info,
1549 "sysfs: failed to update devid for %llu",
1550 device->devid);
1551 }
1552
1553 /* /sys/fs/btrfs/ entry */
1554 static struct kset *btrfs_kset;
1555
1556 /*
1557 * Creates:
1558 * /sys/fs/btrfs/UUID
1559 *
1560 * Can be called by the device discovery thread.
1561 */
1562 int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
1563 {
1564 int error;
1565
1566 init_completion(&fs_devs->kobj_unregister);
1567 fs_devs->fsid_kobj.kset = btrfs_kset;
1568 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
1569 "%pU", fs_devs->fsid);
1570 if (error) {
1571 kobject_put(&fs_devs->fsid_kobj);
1572 return error;
1573 }
1574
1575 fs_devs->devices_kobj = kobject_create_and_add("devices",
1576 &fs_devs->fsid_kobj);
1577 if (!fs_devs->devices_kobj) {
1578 btrfs_err(fs_devs->fs_info,
1579 "failed to init sysfs device interface");
1580 btrfs_sysfs_remove_fsid(fs_devs);
1581 return -ENOMEM;
1582 }
1583
1584 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
1585 &fs_devs->fsid_kobj);
1586 if (!fs_devs->devinfo_kobj) {
1587 btrfs_err(fs_devs->fs_info,
1588 "failed to init sysfs devinfo kobject");
1589 btrfs_sysfs_remove_fsid(fs_devs);
1590 return -ENOMEM;
1591 }
1592
1593 return 0;
1594 }
1595
1596 int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1597 {
1598 int error;
1599 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1600 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1601
1602 error = btrfs_sysfs_add_fs_devices(fs_devs);
1603 if (error)
1604 return error;
1605
1606 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1607 if (error) {
1608 btrfs_sysfs_remove_fs_devices(fs_devs);
1609 return error;
1610 }
1611
1612 error = sysfs_create_group(fsid_kobj,
1613 &btrfs_feature_attr_group);
1614 if (error)
1615 goto failure;
1616
1617 #ifdef CONFIG_BTRFS_DEBUG
1618 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
1619 if (!fs_info->debug_kobj) {
1620 error = -ENOMEM;
1621 goto failure;
1622 }
1623
1624 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1625 if (error)
1626 goto failure;
1627
1628 /* Discard directory */
1629 fs_info->discard_debug_kobj = kobject_create_and_add("discard",
1630 fs_info->debug_kobj);
1631 if (!fs_info->discard_debug_kobj) {
1632 error = -ENOMEM;
1633 goto failure;
1634 }
1635
1636 error = sysfs_create_files(fs_info->discard_debug_kobj,
1637 discard_debug_attrs);
1638 if (error)
1639 goto failure;
1640 #endif
1641
1642 error = addrm_unknown_feature_attrs(fs_info, true);
1643 if (error)
1644 goto failure;
1645
1646 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
1647 if (error)
1648 goto failure;
1649
1650 fs_info->space_info_kobj = kobject_create_and_add("allocation",
1651 fsid_kobj);
1652 if (!fs_info->space_info_kobj) {
1653 error = -ENOMEM;
1654 goto failure;
1655 }
1656
1657 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
1658 if (error)
1659 goto failure;
1660
1661 return 0;
1662 failure:
1663 btrfs_sysfs_remove_mounted(fs_info);
1664 return error;
1665 }
1666
1667 static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
1668 {
1669 return to_fs_info(kobj->parent->parent);
1670 }
1671
1672 #define QGROUP_ATTR(_member, _show_name) \
1673 static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
1674 struct kobj_attribute *a, \
1675 char *buf) \
1676 { \
1677 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1678 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1679 struct btrfs_qgroup, kobj); \
1680 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
1681 } \
1682 BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
1683
1684 #define QGROUP_RSV_ATTR(_name, _type) \
1685 static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
1686 struct kobj_attribute *a, \
1687 char *buf) \
1688 { \
1689 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1690 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1691 struct btrfs_qgroup, kobj); \
1692 return btrfs_show_u64(&qgroup->rsv.values[_type], \
1693 &fs_info->qgroup_lock, buf); \
1694 } \
1695 BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
1696
1697 QGROUP_ATTR(rfer, referenced);
1698 QGROUP_ATTR(excl, exclusive);
1699 QGROUP_ATTR(max_rfer, max_referenced);
1700 QGROUP_ATTR(max_excl, max_exclusive);
1701 QGROUP_ATTR(lim_flags, limit_flags);
1702 QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
1703 QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
1704 QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
1705
1706 static struct attribute *qgroup_attrs[] = {
1707 BTRFS_ATTR_PTR(qgroup, referenced),
1708 BTRFS_ATTR_PTR(qgroup, exclusive),
1709 BTRFS_ATTR_PTR(qgroup, max_referenced),
1710 BTRFS_ATTR_PTR(qgroup, max_exclusive),
1711 BTRFS_ATTR_PTR(qgroup, limit_flags),
1712 BTRFS_ATTR_PTR(qgroup, rsv_data),
1713 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
1714 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
1715 NULL
1716 };
1717 ATTRIBUTE_GROUPS(qgroup);
1718
1719 static void qgroup_release(struct kobject *kobj)
1720 {
1721 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
1722
1723 memset(&qgroup->kobj, 0, sizeof(*kobj));
1724 }
1725
1726 static struct kobj_type qgroup_ktype = {
1727 .sysfs_ops = &kobj_sysfs_ops,
1728 .release = qgroup_release,
1729 .default_groups = qgroup_groups,
1730 };
1731
1732 int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
1733 struct btrfs_qgroup *qgroup)
1734 {
1735 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
1736 int ret;
1737
1738 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1739 return 0;
1740 if (qgroup->kobj.state_initialized)
1741 return 0;
1742 if (!qgroups_kobj)
1743 return -EINVAL;
1744
1745 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
1746 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
1747 btrfs_qgroup_subvolid(qgroup->qgroupid));
1748 if (ret < 0)
1749 kobject_put(&qgroup->kobj);
1750
1751 return ret;
1752 }
1753
1754 void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
1755 {
1756 struct btrfs_qgroup *qgroup;
1757 struct btrfs_qgroup *next;
1758
1759 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1760 return;
1761
1762 rbtree_postorder_for_each_entry_safe(qgroup, next,
1763 &fs_info->qgroup_tree, node)
1764 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1765 if (fs_info->qgroups_kobj) {
1766 kobject_del(fs_info->qgroups_kobj);
1767 kobject_put(fs_info->qgroups_kobj);
1768 fs_info->qgroups_kobj = NULL;
1769 }
1770 }
1771
1772 /* Called when qgroups get initialized, thus there is no need for locking */
1773 int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
1774 {
1775 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1776 struct btrfs_qgroup *qgroup;
1777 struct btrfs_qgroup *next;
1778 int ret = 0;
1779
1780 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1781 return 0;
1782
1783 ASSERT(fsid_kobj);
1784 if (fs_info->qgroups_kobj)
1785 return 0;
1786
1787 fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj);
1788 if (!fs_info->qgroups_kobj) {
1789 ret = -ENOMEM;
1790 goto out;
1791 }
1792 rbtree_postorder_for_each_entry_safe(qgroup, next,
1793 &fs_info->qgroup_tree, node) {
1794 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1795 if (ret < 0)
1796 goto out;
1797 }
1798
1799 out:
1800 if (ret < 0)
1801 btrfs_sysfs_del_qgroups(fs_info);
1802 return ret;
1803 }
1804
1805 void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
1806 struct btrfs_qgroup *qgroup)
1807 {
1808 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1809 return;
1810
1811 if (qgroup->kobj.state_initialized) {
1812 kobject_del(&qgroup->kobj);
1813 kobject_put(&qgroup->kobj);
1814 }
1815 }
1816
1817 /*
1818 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
1819 * values in superblock. Call after any changes to incompat/compat_ro flags
1820 */
1821 void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
1822 u64 bit, enum btrfs_feature_set set)
1823 {
1824 struct btrfs_fs_devices *fs_devs;
1825 struct kobject *fsid_kobj;
1826 u64 __maybe_unused features;
1827 int __maybe_unused ret;
1828
1829 if (!fs_info)
1830 return;
1831
1832 /*
1833 * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not
1834 * safe when called from some contexts (eg. balance)
1835 */
1836 features = get_features(fs_info, set);
1837 ASSERT(bit & supported_feature_masks[set]);
1838
1839 fs_devs = fs_info->fs_devices;
1840 fsid_kobj = &fs_devs->fsid_kobj;
1841
1842 if (!fsid_kobj->state_initialized)
1843 return;
1844
1845 /*
1846 * FIXME: this is too heavy to update just one value, ideally we'd like
1847 * to use sysfs_update_group but some refactoring is needed first.
1848 */
1849 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1850 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
1851 }
1852
1853 int __init btrfs_init_sysfs(void)
1854 {
1855 int ret;
1856
1857 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
1858 if (!btrfs_kset)
1859 return -ENOMEM;
1860
1861 init_feature_attrs();
1862 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1863 if (ret)
1864 goto out2;
1865 ret = sysfs_merge_group(&btrfs_kset->kobj,
1866 &btrfs_static_feature_attr_group);
1867 if (ret)
1868 goto out_remove_group;
1869
1870 #ifdef CONFIG_BTRFS_DEBUG
1871 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1872 if (ret)
1873 goto out2;
1874 #endif
1875
1876 return 0;
1877
1878 out_remove_group:
1879 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1880 out2:
1881 kset_unregister(btrfs_kset);
1882
1883 return ret;
1884 }
1885
1886 void __cold btrfs_exit_sysfs(void)
1887 {
1888 sysfs_unmerge_group(&btrfs_kset->kobj,
1889 &btrfs_static_feature_attr_group);
1890 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
1891 #ifdef CONFIG_BTRFS_DEBUG
1892 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
1893 #endif
1894 kset_unregister(btrfs_kset);
1895 }
1896
Ubuntu Hirsute Linux kernel mirror