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 /*
26 * Structure name Path
27 * --------------------------------------------------------------------------
28 * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features
29 * btrfs_supported_feature_attrs /sys/fs/btrfs/features and
30 * /sys/fs/btrfs/<uuid>/features
31 * btrfs_attrs /sys/fs/btrfs/<uuid>
32 * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid>
33 * allocation_attrs /sys/fs/btrfs/<uuid>/allocation
34 * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>
35 * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>
36 * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>
37 *
38 * When built with BTRFS_CONFIG_DEBUG:
39 *
40 * btrfs_debug_feature_attrs /sys/fs/btrfs/debug
41 * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug
42 * discard_debug_attrs /sys/fs/btrfs/<uuid>/debug/discard
43 */
44
45 struct btrfs_feature_attr {
46 struct kobj_attribute kobj_attr;
47 enum btrfs_feature_set feature_set;
48 u64 feature_bit;
49 };
50
51 /* For raid type sysfs entries */
52 struct raid_kobject {
53 u64 flags;
54 struct kobject kobj;
55 };
56
57 #define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
58 { \
59 .attr = { .name = __stringify(_name), .mode = _mode }, \
60 .show = _show, \
61 .store = _store, \
62 }
63
64 #define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \
65 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
66 __INIT_KOBJ_ATTR(_name, 0644, _show, _store)
67
68 #define BTRFS_ATTR(_prefix, _name, _show) \
69 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \
70 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
71
72 #define BTRFS_ATTR_PTR(_prefix, _name) \
73 (&btrfs_attr_##_prefix##_##_name.attr)
74
75 #define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \
76 static struct btrfs_feature_attr btrfs_attr_features_##_name = { \
77 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
78 btrfs_feature_attr_show, \
79 btrfs_feature_attr_store), \
80 .feature_set = _feature_set, \
81 .feature_bit = _feature_prefix ##_## _feature_bit, \
82 }
83 #define BTRFS_FEAT_ATTR_PTR(_name) \
84 (&btrfs_attr_features_##_name.kobj_attr.attr)
85
86 #define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
87 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
88 #define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
89 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
90 #define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
91 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
92
93 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
94 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
95
to_btrfs_feature_attr(struct kobj_attribute * a)96 static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
97 {
98 return container_of(a, struct btrfs_feature_attr, kobj_attr);
99 }
100
attr_to_btrfs_attr(struct attribute * attr)101 static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
102 {
103 return container_of(attr, struct kobj_attribute, attr);
104 }
105
attr_to_btrfs_feature_attr(struct attribute * attr)106 static struct btrfs_feature_attr *attr_to_btrfs_feature_attr(
107 struct attribute *attr)
108 {
109 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
110 }
111
get_features(struct btrfs_fs_info * fs_info,enum btrfs_feature_set set)112 static u64 get_features(struct btrfs_fs_info *fs_info,
113 enum btrfs_feature_set set)
114 {
115 struct btrfs_super_block *disk_super = fs_info->super_copy;
116 if (set == FEAT_COMPAT)
117 return btrfs_super_compat_flags(disk_super);
118 else if (set == FEAT_COMPAT_RO)
119 return btrfs_super_compat_ro_flags(disk_super);
120 else
121 return btrfs_super_incompat_flags(disk_super);
122 }
123
set_features(struct btrfs_fs_info * fs_info,enum btrfs_feature_set set,u64 features)124 static void set_features(struct btrfs_fs_info *fs_info,
125 enum btrfs_feature_set set, u64 features)
126 {
127 struct btrfs_super_block *disk_super = fs_info->super_copy;
128 if (set == FEAT_COMPAT)
129 btrfs_set_super_compat_flags(disk_super, features);
130 else if (set == FEAT_COMPAT_RO)
131 btrfs_set_super_compat_ro_flags(disk_super, features);
132 else
133 btrfs_set_super_incompat_flags(disk_super, features);
134 }
135
can_modify_feature(struct btrfs_feature_attr * fa)136 static int can_modify_feature(struct btrfs_feature_attr *fa)
137 {
138 int val = 0;
139 u64 set, clear;
140 switch (fa->feature_set) {
141 case FEAT_COMPAT:
142 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
143 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
144 break;
145 case FEAT_COMPAT_RO:
146 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
147 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
148 break;
149 case FEAT_INCOMPAT:
150 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
151 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
152 break;
153 default:
154 pr_warn("btrfs: sysfs: unknown feature set %d\n",
155 fa->feature_set);
156 return 0;
157 }
158
159 if (set & fa->feature_bit)
160 val |= 1;
161 if (clear & fa->feature_bit)
162 val |= 2;
163
164 return val;
165 }
166
btrfs_feature_attr_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)167 static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
168 struct kobj_attribute *a, char *buf)
169 {
170 int val = 0;
171 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
172 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
173 if (fs_info) {
174 u64 features = get_features(fs_info, fa->feature_set);
175 if (features & fa->feature_bit)
176 val = 1;
177 } else
178 val = can_modify_feature(fa);
179
180 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
181 }
182
btrfs_feature_attr_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t count)183 static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
184 struct kobj_attribute *a,
185 const char *buf, size_t count)
186 {
187 struct btrfs_fs_info *fs_info;
188 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
189 u64 features, set, clear;
190 unsigned long val;
191 int ret;
192
193 fs_info = to_fs_info(kobj);
194 if (!fs_info)
195 return -EPERM;
196
197 if (sb_rdonly(fs_info->sb))
198 return -EROFS;
199
200 ret = kstrtoul(skip_spaces(buf), 0, &val);
201 if (ret)
202 return ret;
203
204 if (fa->feature_set == FEAT_COMPAT) {
205 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
206 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
207 } else if (fa->feature_set == FEAT_COMPAT_RO) {
208 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
209 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
210 } else {
211 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
212 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
213 }
214
215 features = get_features(fs_info, fa->feature_set);
216
217 /* Nothing to do */
218 if ((val && (features & fa->feature_bit)) ||
219 (!val && !(features & fa->feature_bit)))
220 return count;
221
222 if ((val && !(set & fa->feature_bit)) ||
223 (!val && !(clear & fa->feature_bit))) {
224 btrfs_info(fs_info,
225 "%sabling feature %s on mounted fs is not supported.",
226 val ? "En" : "Dis", fa->kobj_attr.attr.name);
227 return -EPERM;
228 }
229
230 btrfs_info(fs_info, "%s %s feature flag",
231 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
232
233 spin_lock(&fs_info->super_lock);
234 features = get_features(fs_info, fa->feature_set);
235 if (val)
236 features |= fa->feature_bit;
237 else
238 features &= ~fa->feature_bit;
239 set_features(fs_info, fa->feature_set, features);
240 spin_unlock(&fs_info->super_lock);
241
242 /*
243 * We don't want to do full transaction commit from inside sysfs
244 */
245 btrfs_set_pending(fs_info, COMMIT);
246 wake_up_process(fs_info->transaction_kthread);
247
248 return count;
249 }
250
btrfs_feature_visible(struct kobject * kobj,struct attribute * attr,int unused)251 static umode_t btrfs_feature_visible(struct kobject *kobj,
252 struct attribute *attr, int unused)
253 {
254 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
255 umode_t mode = attr->mode;
256
257 if (fs_info) {
258 struct btrfs_feature_attr *fa;
259 u64 features;
260
261 fa = attr_to_btrfs_feature_attr(attr);
262 features = get_features(fs_info, fa->feature_set);
263
264 if (can_modify_feature(fa))
265 mode |= S_IWUSR;
266 else if (!(features & fa->feature_bit))
267 mode = 0;
268 }
269
270 return mode;
271 }
272
273 BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
274 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
275 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
276 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
277 BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
278 BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
279 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
280 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
281 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
282 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
283 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
284 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
285 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
286 #ifdef CONFIG_BTRFS_DEBUG
287 /* Remove once support for zoned allocation is feature complete */
288 BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
289 /* Remove once support for extent tree v2 is feature complete */
290 BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2);
291 #endif
292 #ifdef CONFIG_FS_VERITY
293 BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
294 #endif
295
296 /*
297 * Features which depend on feature bits and may differ between each fs.
298 *
299 * /sys/fs/btrfs/features - all available features implemeted by this version
300 * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or
301 * can be changed on a mounted filesystem.
302 */
303 static struct attribute *btrfs_supported_feature_attrs[] = {
304 BTRFS_FEAT_ATTR_PTR(mixed_backref),
305 BTRFS_FEAT_ATTR_PTR(default_subvol),
306 BTRFS_FEAT_ATTR_PTR(mixed_groups),
307 BTRFS_FEAT_ATTR_PTR(compress_lzo),
308 BTRFS_FEAT_ATTR_PTR(compress_zstd),
309 BTRFS_FEAT_ATTR_PTR(big_metadata),
310 BTRFS_FEAT_ATTR_PTR(extended_iref),
311 BTRFS_FEAT_ATTR_PTR(raid56),
312 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
313 BTRFS_FEAT_ATTR_PTR(no_holes),
314 BTRFS_FEAT_ATTR_PTR(metadata_uuid),
315 BTRFS_FEAT_ATTR_PTR(free_space_tree),
316 BTRFS_FEAT_ATTR_PTR(raid1c34),
317 #ifdef CONFIG_BTRFS_DEBUG
318 BTRFS_FEAT_ATTR_PTR(zoned),
319 BTRFS_FEAT_ATTR_PTR(extent_tree_v2),
320 #endif
321 #ifdef CONFIG_FS_VERITY
322 BTRFS_FEAT_ATTR_PTR(verity),
323 #endif
324 NULL
325 };
326
327 static const struct attribute_group btrfs_feature_attr_group = {
328 .name = "features",
329 .is_visible = btrfs_feature_visible,
330 .attrs = btrfs_supported_feature_attrs,
331 };
332
rmdir_subvol_show(struct kobject * kobj,struct kobj_attribute * ka,char * buf)333 static ssize_t rmdir_subvol_show(struct kobject *kobj,
334 struct kobj_attribute *ka, char *buf)
335 {
336 return scnprintf(buf, PAGE_SIZE, "0\n");
337 }
338 BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
339
supported_checksums_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)340 static ssize_t supported_checksums_show(struct kobject *kobj,
341 struct kobj_attribute *a, char *buf)
342 {
343 ssize_t ret = 0;
344 int i;
345
346 for (i = 0; i < btrfs_get_num_csums(); i++) {
347 /*
348 * This "trick" only works as long as 'enum btrfs_csum_type' has
349 * no holes in it
350 */
351 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
352 (i == 0 ? "" : " "), btrfs_super_csum_name(i));
353
354 }
355
356 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
357 return ret;
358 }
359 BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
360
send_stream_version_show(struct kobject * kobj,struct kobj_attribute * ka,char * buf)361 static ssize_t send_stream_version_show(struct kobject *kobj,
362 struct kobj_attribute *ka, char *buf)
363 {
364 return snprintf(buf, PAGE_SIZE, "%d\n", BTRFS_SEND_STREAM_VERSION);
365 }
366 BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
367
368 static const char *rescue_opts[] = {
369 "usebackuproot",
370 "nologreplay",
371 "ignorebadroots",
372 "ignoredatacsums",
373 "all",
374 };
375
supported_rescue_options_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)376 static ssize_t supported_rescue_options_show(struct kobject *kobj,
377 struct kobj_attribute *a,
378 char *buf)
379 {
380 ssize_t ret = 0;
381 int i;
382
383 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
384 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
385 (i ? " " : ""), rescue_opts[i]);
386 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
387 return ret;
388 }
389 BTRFS_ATTR(static_feature, supported_rescue_options,
390 supported_rescue_options_show);
391
supported_sectorsizes_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)392 static ssize_t supported_sectorsizes_show(struct kobject *kobj,
393 struct kobj_attribute *a,
394 char *buf)
395 {
396 ssize_t ret = 0;
397
398 /* 4K sector size is also supported with 64K page size */
399 if (PAGE_SIZE == SZ_64K)
400 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%u ", SZ_4K);
401
402 /* Only sectorsize == PAGE_SIZE is now supported */
403 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%lu\n", PAGE_SIZE);
404
405 return ret;
406 }
407 BTRFS_ATTR(static_feature, supported_sectorsizes,
408 supported_sectorsizes_show);
409
410 /*
411 * Features which only depend on kernel version.
412 *
413 * These are listed in /sys/fs/btrfs/features along with
414 * btrfs_supported_feature_attrs.
415 */
416 static struct attribute *btrfs_supported_static_feature_attrs[] = {
417 BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
418 BTRFS_ATTR_PTR(static_feature, supported_checksums),
419 BTRFS_ATTR_PTR(static_feature, send_stream_version),
420 BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
421 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
422 NULL
423 };
424
425 static const struct attribute_group btrfs_static_feature_attr_group = {
426 .name = "features",
427 .attrs = btrfs_supported_static_feature_attrs,
428 };
429
430 #ifdef CONFIG_BTRFS_DEBUG
431
432 /*
433 * Discard statistics and tunables
434 */
435 #define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent)
436
btrfs_discardable_bytes_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)437 static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
438 struct kobj_attribute *a,
439 char *buf)
440 {
441 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
442
443 return scnprintf(buf, PAGE_SIZE, "%lld\n",
444 atomic64_read(&fs_info->discard_ctl.discardable_bytes));
445 }
446 BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
447
btrfs_discardable_extents_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)448 static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
449 struct kobj_attribute *a,
450 char *buf)
451 {
452 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
453
454 return scnprintf(buf, PAGE_SIZE, "%d\n",
455 atomic_read(&fs_info->discard_ctl.discardable_extents));
456 }
457 BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
458
btrfs_discard_bitmap_bytes_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)459 static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
460 struct kobj_attribute *a,
461 char *buf)
462 {
463 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
464
465 return scnprintf(buf, PAGE_SIZE, "%llu\n",
466 fs_info->discard_ctl.discard_bitmap_bytes);
467 }
468 BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
469
btrfs_discard_bytes_saved_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)470 static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
471 struct kobj_attribute *a,
472 char *buf)
473 {
474 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
475
476 return scnprintf(buf, PAGE_SIZE, "%lld\n",
477 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
478 }
479 BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
480
btrfs_discard_extent_bytes_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)481 static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
482 struct kobj_attribute *a,
483 char *buf)
484 {
485 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
486
487 return scnprintf(buf, PAGE_SIZE, "%llu\n",
488 fs_info->discard_ctl.discard_extent_bytes);
489 }
490 BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
491
btrfs_discard_iops_limit_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)492 static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
493 struct kobj_attribute *a,
494 char *buf)
495 {
496 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
497
498 return scnprintf(buf, PAGE_SIZE, "%u\n",
499 READ_ONCE(fs_info->discard_ctl.iops_limit));
500 }
501
btrfs_discard_iops_limit_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)502 static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
503 struct kobj_attribute *a,
504 const char *buf, size_t len)
505 {
506 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
507 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
508 u32 iops_limit;
509 int ret;
510
511 ret = kstrtou32(buf, 10, &iops_limit);
512 if (ret)
513 return -EINVAL;
514
515 WRITE_ONCE(discard_ctl->iops_limit, iops_limit);
516 btrfs_discard_calc_delay(discard_ctl);
517 btrfs_discard_schedule_work(discard_ctl, true);
518 return len;
519 }
520 BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show,
521 btrfs_discard_iops_limit_store);
522
btrfs_discard_kbps_limit_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)523 static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
524 struct kobj_attribute *a,
525 char *buf)
526 {
527 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
528
529 return scnprintf(buf, PAGE_SIZE, "%u\n",
530 READ_ONCE(fs_info->discard_ctl.kbps_limit));
531 }
532
btrfs_discard_kbps_limit_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)533 static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
534 struct kobj_attribute *a,
535 const char *buf, size_t len)
536 {
537 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
538 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
539 u32 kbps_limit;
540 int ret;
541
542 ret = kstrtou32(buf, 10, &kbps_limit);
543 if (ret)
544 return -EINVAL;
545
546 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit);
547 btrfs_discard_schedule_work(discard_ctl, true);
548 return len;
549 }
550 BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show,
551 btrfs_discard_kbps_limit_store);
552
btrfs_discard_max_discard_size_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)553 static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
554 struct kobj_attribute *a,
555 char *buf)
556 {
557 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
558
559 return scnprintf(buf, PAGE_SIZE, "%llu\n",
560 READ_ONCE(fs_info->discard_ctl.max_discard_size));
561 }
562
btrfs_discard_max_discard_size_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)563 static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
564 struct kobj_attribute *a,
565 const char *buf, size_t len)
566 {
567 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
568 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl;
569 u64 max_discard_size;
570 int ret;
571
572 ret = kstrtou64(buf, 10, &max_discard_size);
573 if (ret)
574 return -EINVAL;
575
576 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size);
577
578 return len;
579 }
580 BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
581 btrfs_discard_max_discard_size_store);
582
583 /*
584 * Per-filesystem debugging of discard (when mounted with discard=async).
585 *
586 * Path: /sys/fs/btrfs/<uuid>/debug/discard/
587 */
588 static const struct attribute *discard_debug_attrs[] = {
589 BTRFS_ATTR_PTR(discard, discardable_bytes),
590 BTRFS_ATTR_PTR(discard, discardable_extents),
591 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
592 BTRFS_ATTR_PTR(discard, discard_bytes_saved),
593 BTRFS_ATTR_PTR(discard, discard_extent_bytes),
594 BTRFS_ATTR_PTR(discard, iops_limit),
595 BTRFS_ATTR_PTR(discard, kbps_limit),
596 BTRFS_ATTR_PTR(discard, max_discard_size),
597 NULL,
598 };
599
600 /*
601 * Per-filesystem runtime debugging exported via sysfs.
602 *
603 * Path: /sys/fs/btrfs/UUID/debug/
604 */
605 static const struct attribute *btrfs_debug_mount_attrs[] = {
606 NULL,
607 };
608
609 /*
610 * Runtime debugging exported via sysfs, applies to all mounted filesystems.
611 *
612 * Path: /sys/fs/btrfs/debug
613 */
614 static struct attribute *btrfs_debug_feature_attrs[] = {
615 NULL
616 };
617
618 static const struct attribute_group btrfs_debug_feature_attr_group = {
619 .name = "debug",
620 .attrs = btrfs_debug_feature_attrs,
621 };
622
623 #endif
624
btrfs_show_u64(u64 * value_ptr,spinlock_t * lock,char * buf)625 static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
626 {
627 u64 val;
628 if (lock)
629 spin_lock(lock);
630 val = *value_ptr;
631 if (lock)
632 spin_unlock(lock);
633 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
634 }
635
global_rsv_size_show(struct kobject * kobj,struct kobj_attribute * ka,char * buf)636 static ssize_t global_rsv_size_show(struct kobject *kobj,
637 struct kobj_attribute *ka, char *buf)
638 {
639 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
640 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
641 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
642 }
643 BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show);
644
global_rsv_reserved_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)645 static ssize_t global_rsv_reserved_show(struct kobject *kobj,
646 struct kobj_attribute *a, char *buf)
647 {
648 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
649 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
650 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
651 }
652 BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show);
653
654 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
655 #define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
656
657 static ssize_t raid_bytes_show(struct kobject *kobj,
658 struct kobj_attribute *attr, char *buf);
659 BTRFS_ATTR(raid, total_bytes, raid_bytes_show);
660 BTRFS_ATTR(raid, used_bytes, raid_bytes_show);
661
raid_bytes_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)662 static ssize_t raid_bytes_show(struct kobject *kobj,
663 struct kobj_attribute *attr, char *buf)
664
665 {
666 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
667 struct btrfs_block_group *block_group;
668 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags);
669 u64 val = 0;
670
671 down_read(&sinfo->groups_sem);
672 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
673 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes))
674 val += block_group->length;
675 else
676 val += block_group->used;
677 }
678 up_read(&sinfo->groups_sem);
679 return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
680 }
681
682 /*
683 * Allocation information about block group profiles.
684 *
685 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/
686 */
687 static struct attribute *raid_attrs[] = {
688 BTRFS_ATTR_PTR(raid, total_bytes),
689 BTRFS_ATTR_PTR(raid, used_bytes),
690 NULL
691 };
692 ATTRIBUTE_GROUPS(raid);
693
release_raid_kobj(struct kobject * kobj)694 static void release_raid_kobj(struct kobject *kobj)
695 {
696 kfree(to_raid_kobj(kobj));
697 }
698
699 static struct kobj_type btrfs_raid_ktype = {
700 .sysfs_ops = &kobj_sysfs_ops,
701 .release = release_raid_kobj,
702 .default_groups = raid_groups,
703 };
704
705 #define SPACE_INFO_ATTR(field) \
706 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
707 struct kobj_attribute *a, \
708 char *buf) \
709 { \
710 struct btrfs_space_info *sinfo = to_space_info(kobj); \
711 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
712 } \
713 BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
714
715 SPACE_INFO_ATTR(flags);
716 SPACE_INFO_ATTR(total_bytes);
717 SPACE_INFO_ATTR(bytes_used);
718 SPACE_INFO_ATTR(bytes_pinned);
719 SPACE_INFO_ATTR(bytes_reserved);
720 SPACE_INFO_ATTR(bytes_may_use);
721 SPACE_INFO_ATTR(bytes_readonly);
722 SPACE_INFO_ATTR(bytes_zone_unusable);
723 SPACE_INFO_ATTR(disk_used);
724 SPACE_INFO_ATTR(disk_total);
725
726 /*
727 * Allocation information about block group types.
728 *
729 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/
730 */
731 static struct attribute *space_info_attrs[] = {
732 BTRFS_ATTR_PTR(space_info, flags),
733 BTRFS_ATTR_PTR(space_info, total_bytes),
734 BTRFS_ATTR_PTR(space_info, bytes_used),
735 BTRFS_ATTR_PTR(space_info, bytes_pinned),
736 BTRFS_ATTR_PTR(space_info, bytes_reserved),
737 BTRFS_ATTR_PTR(space_info, bytes_may_use),
738 BTRFS_ATTR_PTR(space_info, bytes_readonly),
739 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
740 BTRFS_ATTR_PTR(space_info, disk_used),
741 BTRFS_ATTR_PTR(space_info, disk_total),
742 NULL,
743 };
744 ATTRIBUTE_GROUPS(space_info);
745
space_info_release(struct kobject * kobj)746 static void space_info_release(struct kobject *kobj)
747 {
748 struct btrfs_space_info *sinfo = to_space_info(kobj);
749 kfree(sinfo);
750 }
751
752 static struct kobj_type space_info_ktype = {
753 .sysfs_ops = &kobj_sysfs_ops,
754 .release = space_info_release,
755 .default_groups = space_info_groups,
756 };
757
758 /*
759 * Allocation information about block groups.
760 *
761 * Path: /sys/fs/btrfs/<uuid>/allocation/
762 */
763 static const struct attribute *allocation_attrs[] = {
764 BTRFS_ATTR_PTR(allocation, global_rsv_reserved),
765 BTRFS_ATTR_PTR(allocation, global_rsv_size),
766 NULL,
767 };
768
btrfs_label_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)769 static ssize_t btrfs_label_show(struct kobject *kobj,
770 struct kobj_attribute *a, char *buf)
771 {
772 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
773 char *label = fs_info->super_copy->label;
774 ssize_t ret;
775
776 spin_lock(&fs_info->super_lock);
777 ret = scnprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
778 spin_unlock(&fs_info->super_lock);
779
780 return ret;
781 }
782
btrfs_label_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)783 static ssize_t btrfs_label_store(struct kobject *kobj,
784 struct kobj_attribute *a,
785 const char *buf, size_t len)
786 {
787 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
788 size_t p_len;
789
790 if (!fs_info)
791 return -EPERM;
792
793 if (sb_rdonly(fs_info->sb))
794 return -EROFS;
795
796 /*
797 * p_len is the len until the first occurrence of either
798 * '\n' or '\0'
799 */
800 p_len = strcspn(buf, "\n");
801
802 if (p_len >= BTRFS_LABEL_SIZE)
803 return -EINVAL;
804
805 spin_lock(&fs_info->super_lock);
806 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
807 memcpy(fs_info->super_copy->label, buf, p_len);
808 spin_unlock(&fs_info->super_lock);
809
810 /*
811 * We don't want to do full transaction commit from inside sysfs
812 */
813 btrfs_set_pending(fs_info, COMMIT);
814 wake_up_process(fs_info->transaction_kthread);
815
816 return len;
817 }
818 BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store);
819
btrfs_nodesize_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)820 static ssize_t btrfs_nodesize_show(struct kobject *kobj,
821 struct kobj_attribute *a, char *buf)
822 {
823 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
824
825 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
826 }
827
828 BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
829
btrfs_sectorsize_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)830 static ssize_t btrfs_sectorsize_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, "%u\n",
836 fs_info->super_copy->sectorsize);
837 }
838
839 BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
840
btrfs_clone_alignment_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)841 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
842 struct kobj_attribute *a, char *buf)
843 {
844 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
845
846 return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
847 }
848
849 BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
850
quota_override_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)851 static ssize_t quota_override_show(struct kobject *kobj,
852 struct kobj_attribute *a, char *buf)
853 {
854 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
855 int quota_override;
856
857 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
858 return scnprintf(buf, PAGE_SIZE, "%d\n", quota_override);
859 }
860
quota_override_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)861 static ssize_t quota_override_store(struct kobject *kobj,
862 struct kobj_attribute *a,
863 const char *buf, size_t len)
864 {
865 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
866 unsigned long knob;
867 int err;
868
869 if (!fs_info)
870 return -EPERM;
871
872 if (!capable(CAP_SYS_RESOURCE))
873 return -EPERM;
874
875 err = kstrtoul(buf, 10, &knob);
876 if (err)
877 return err;
878 if (knob > 1)
879 return -EINVAL;
880
881 if (knob)
882 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
883 else
884 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
885
886 return len;
887 }
888
889 BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store);
890
btrfs_metadata_uuid_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)891 static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
892 struct kobj_attribute *a, char *buf)
893 {
894 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
895
896 return scnprintf(buf, PAGE_SIZE, "%pU\n",
897 fs_info->fs_devices->metadata_uuid);
898 }
899
900 BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
901
btrfs_checksum_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)902 static ssize_t btrfs_checksum_show(struct kobject *kobj,
903 struct kobj_attribute *a, char *buf)
904 {
905 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
906 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
907
908 return scnprintf(buf, PAGE_SIZE, "%s (%s)\n",
909 btrfs_super_csum_name(csum_type),
910 crypto_shash_driver_name(fs_info->csum_shash));
911 }
912
913 BTRFS_ATTR(, checksum, btrfs_checksum_show);
914
btrfs_exclusive_operation_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)915 static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
916 struct kobj_attribute *a, char *buf)
917 {
918 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
919 const char *str;
920
921 switch (READ_ONCE(fs_info->exclusive_operation)) {
922 case BTRFS_EXCLOP_NONE:
923 str = "none\n";
924 break;
925 case BTRFS_EXCLOP_BALANCE:
926 str = "balance\n";
927 break;
928 case BTRFS_EXCLOP_DEV_ADD:
929 str = "device add\n";
930 break;
931 case BTRFS_EXCLOP_DEV_REMOVE:
932 str = "device remove\n";
933 break;
934 case BTRFS_EXCLOP_DEV_REPLACE:
935 str = "device replace\n";
936 break;
937 case BTRFS_EXCLOP_RESIZE:
938 str = "resize\n";
939 break;
940 case BTRFS_EXCLOP_SWAP_ACTIVATE:
941 str = "swap activate\n";
942 break;
943 default:
944 str = "UNKNOWN\n";
945 break;
946 }
947 return scnprintf(buf, PAGE_SIZE, "%s", str);
948 }
949 BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
950
btrfs_generation_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)951 static ssize_t btrfs_generation_show(struct kobject *kobj,
952 struct kobj_attribute *a, char *buf)
953 {
954 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
955
956 return scnprintf(buf, PAGE_SIZE, "%llu\n", fs_info->generation);
957 }
958 BTRFS_ATTR(, generation, btrfs_generation_show);
959
960 /*
961 * Look for an exact string @string in @buffer with possible leading or
962 * trailing whitespace
963 */
strmatch(const char * buffer,const char * string)964 static bool strmatch(const char *buffer, const char *string)
965 {
966 const size_t len = strlen(string);
967
968 /* Skip leading whitespace */
969 buffer = skip_spaces(buffer);
970
971 /* Match entire string, check if the rest is whitespace or empty */
972 if (strncmp(string, buffer, len) == 0 &&
973 strlen(skip_spaces(buffer + len)) == 0)
974 return true;
975
976 return false;
977 }
978
979 static const char * const btrfs_read_policy_name[] = { "pid" };
980
btrfs_read_policy_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)981 static ssize_t btrfs_read_policy_show(struct kobject *kobj,
982 struct kobj_attribute *a, char *buf)
983 {
984 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
985 ssize_t ret = 0;
986 int i;
987
988 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
989 if (fs_devices->read_policy == i)
990 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s[%s]",
991 (ret == 0 ? "" : " "),
992 btrfs_read_policy_name[i]);
993 else
994 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
995 (ret == 0 ? "" : " "),
996 btrfs_read_policy_name[i]);
997 }
998
999 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
1000
1001 return ret;
1002 }
1003
btrfs_read_policy_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)1004 static ssize_t btrfs_read_policy_store(struct kobject *kobj,
1005 struct kobj_attribute *a,
1006 const char *buf, size_t len)
1007 {
1008 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
1009 int i;
1010
1011 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
1012 if (strmatch(buf, btrfs_read_policy_name[i])) {
1013 if (i != fs_devices->read_policy) {
1014 fs_devices->read_policy = i;
1015 btrfs_info(fs_devices->fs_info,
1016 "read policy set to '%s'",
1017 btrfs_read_policy_name[i]);
1018 }
1019 return len;
1020 }
1021 }
1022
1023 return -EINVAL;
1024 }
1025 BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
1026
btrfs_bg_reclaim_threshold_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1027 static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
1028 struct kobj_attribute *a,
1029 char *buf)
1030 {
1031 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1032 ssize_t ret;
1033
1034 ret = scnprintf(buf, PAGE_SIZE, "%d\n",
1035 READ_ONCE(fs_info->bg_reclaim_threshold));
1036
1037 return ret;
1038 }
1039
btrfs_bg_reclaim_threshold_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)1040 static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
1041 struct kobj_attribute *a,
1042 const char *buf, size_t len)
1043 {
1044 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
1045 int thresh;
1046 int ret;
1047
1048 ret = kstrtoint(buf, 10, &thresh);
1049 if (ret)
1050 return ret;
1051
1052 if (thresh != 0 && (thresh <= 50 || thresh > 100))
1053 return -EINVAL;
1054
1055 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
1056
1057 return len;
1058 }
1059 BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
1060 btrfs_bg_reclaim_threshold_store);
1061
1062 /*
1063 * Per-filesystem information and stats.
1064 *
1065 * Path: /sys/fs/btrfs/<uuid>/
1066 */
1067 static const struct attribute *btrfs_attrs[] = {
1068 BTRFS_ATTR_PTR(, label),
1069 BTRFS_ATTR_PTR(, nodesize),
1070 BTRFS_ATTR_PTR(, sectorsize),
1071 BTRFS_ATTR_PTR(, clone_alignment),
1072 BTRFS_ATTR_PTR(, quota_override),
1073 BTRFS_ATTR_PTR(, metadata_uuid),
1074 BTRFS_ATTR_PTR(, checksum),
1075 BTRFS_ATTR_PTR(, exclusive_operation),
1076 BTRFS_ATTR_PTR(, generation),
1077 BTRFS_ATTR_PTR(, read_policy),
1078 BTRFS_ATTR_PTR(, bg_reclaim_threshold),
1079 NULL,
1080 };
1081
btrfs_release_fsid_kobj(struct kobject * kobj)1082 static void btrfs_release_fsid_kobj(struct kobject *kobj)
1083 {
1084 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
1085
1086 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject));
1087 complete(&fs_devs->kobj_unregister);
1088 }
1089
1090 static struct kobj_type btrfs_ktype = {
1091 .sysfs_ops = &kobj_sysfs_ops,
1092 .release = btrfs_release_fsid_kobj,
1093 };
1094
to_fs_devs(struct kobject * kobj)1095 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
1096 {
1097 if (kobj->ktype != &btrfs_ktype)
1098 return NULL;
1099 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj);
1100 }
1101
to_fs_info(struct kobject * kobj)1102 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
1103 {
1104 if (kobj->ktype != &btrfs_ktype)
1105 return NULL;
1106 return to_fs_devs(kobj)->fs_info;
1107 }
1108
1109 #define NUM_FEATURE_BITS 64
1110 #define BTRFS_FEATURE_NAME_MAX 13
1111 static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
1112 static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
1113
1114 static const u64 supported_feature_masks[FEAT_MAX] = {
1115 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
1116 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
1117 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
1118 };
1119
addrm_unknown_feature_attrs(struct btrfs_fs_info * fs_info,bool add)1120 static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
1121 {
1122 int set;
1123
1124 for (set = 0; set < FEAT_MAX; set++) {
1125 int i;
1126 struct attribute *attrs[2];
1127 struct attribute_group agroup = {
1128 .name = "features",
1129 .attrs = attrs,
1130 };
1131 u64 features = get_features(fs_info, set);
1132 features &= ~supported_feature_masks[set];
1133
1134 if (!features)
1135 continue;
1136
1137 attrs[1] = NULL;
1138 for (i = 0; i < NUM_FEATURE_BITS; i++) {
1139 struct btrfs_feature_attr *fa;
1140
1141 if (!(features & (1ULL << i)))
1142 continue;
1143
1144 fa = &btrfs_feature_attrs[set][i];
1145 attrs[0] = &fa->kobj_attr.attr;
1146 if (add) {
1147 int ret;
1148 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj,
1149 &agroup);
1150 if (ret)
1151 return ret;
1152 } else
1153 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj,
1154 &agroup);
1155 }
1156
1157 }
1158 return 0;
1159 }
1160
__btrfs_sysfs_remove_fsid(struct btrfs_fs_devices * fs_devs)1161 static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1162 {
1163 if (fs_devs->devinfo_kobj) {
1164 kobject_del(fs_devs->devinfo_kobj);
1165 kobject_put(fs_devs->devinfo_kobj);
1166 fs_devs->devinfo_kobj = NULL;
1167 }
1168
1169 if (fs_devs->devices_kobj) {
1170 kobject_del(fs_devs->devices_kobj);
1171 kobject_put(fs_devs->devices_kobj);
1172 fs_devs->devices_kobj = NULL;
1173 }
1174
1175 if (fs_devs->fsid_kobj.state_initialized) {
1176 kobject_del(&fs_devs->fsid_kobj);
1177 kobject_put(&fs_devs->fsid_kobj);
1178 wait_for_completion(&fs_devs->kobj_unregister);
1179 }
1180 }
1181
1182 /* when fs_devs is NULL it will remove all fsid kobject */
btrfs_sysfs_remove_fsid(struct btrfs_fs_devices * fs_devs)1183 void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
1184 {
1185 struct list_head *fs_uuids = btrfs_get_fs_uuids();
1186
1187 if (fs_devs) {
1188 __btrfs_sysfs_remove_fsid(fs_devs);
1189 return;
1190 }
1191
1192 list_for_each_entry(fs_devs, fs_uuids, fs_list) {
1193 __btrfs_sysfs_remove_fsid(fs_devs);
1194 }
1195 }
1196
btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices * fs_devices)1197 static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices)
1198 {
1199 struct btrfs_device *device;
1200 struct btrfs_fs_devices *seed;
1201
1202 list_for_each_entry(device, &fs_devices->devices, dev_list)
1203 btrfs_sysfs_remove_device(device);
1204
1205 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1206 list_for_each_entry(device, &seed->devices, dev_list)
1207 btrfs_sysfs_remove_device(device);
1208 }
1209 }
1210
btrfs_sysfs_remove_mounted(struct btrfs_fs_info * fs_info)1211 void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
1212 {
1213 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1214
1215 sysfs_remove_link(fsid_kobj, "bdi");
1216
1217 if (fs_info->space_info_kobj) {
1218 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
1219 kobject_del(fs_info->space_info_kobj);
1220 kobject_put(fs_info->space_info_kobj);
1221 }
1222 #ifdef CONFIG_BTRFS_DEBUG
1223 if (fs_info->discard_debug_kobj) {
1224 sysfs_remove_files(fs_info->discard_debug_kobj,
1225 discard_debug_attrs);
1226 kobject_del(fs_info->discard_debug_kobj);
1227 kobject_put(fs_info->discard_debug_kobj);
1228 }
1229 if (fs_info->debug_kobj) {
1230 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1231 kobject_del(fs_info->debug_kobj);
1232 kobject_put(fs_info->debug_kobj);
1233 }
1234 #endif
1235 addrm_unknown_feature_attrs(fs_info, false);
1236 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
1237 sysfs_remove_files(fsid_kobj, btrfs_attrs);
1238 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices);
1239 }
1240
1241 static const char * const btrfs_feature_set_names[FEAT_MAX] = {
1242 [FEAT_COMPAT] = "compat",
1243 [FEAT_COMPAT_RO] = "compat_ro",
1244 [FEAT_INCOMPAT] = "incompat",
1245 };
1246
btrfs_feature_set_name(enum btrfs_feature_set set)1247 const char *btrfs_feature_set_name(enum btrfs_feature_set set)
1248 {
1249 return btrfs_feature_set_names[set];
1250 }
1251
btrfs_printable_features(enum btrfs_feature_set set,u64 flags)1252 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
1253 {
1254 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
1255 int len = 0;
1256 int i;
1257 char *str;
1258
1259 str = kmalloc(bufsize, GFP_KERNEL);
1260 if (!str)
1261 return str;
1262
1263 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1264 const char *name;
1265
1266 if (!(flags & (1ULL << i)))
1267 continue;
1268
1269 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
1270 len += scnprintf(str + len, bufsize - len, "%s%s",
1271 len ? "," : "", name);
1272 }
1273
1274 return str;
1275 }
1276
init_feature_attrs(void)1277 static void init_feature_attrs(void)
1278 {
1279 struct btrfs_feature_attr *fa;
1280 int set, i;
1281
1282 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
1283 ARRAY_SIZE(btrfs_feature_attrs));
1284 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
1285 ARRAY_SIZE(btrfs_feature_attrs[0]));
1286
1287 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
1288 memset(btrfs_unknown_feature_names, 0,
1289 sizeof(btrfs_unknown_feature_names));
1290
1291 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
1292 struct btrfs_feature_attr *sfa;
1293 struct attribute *a = btrfs_supported_feature_attrs[i];
1294 int bit;
1295 sfa = attr_to_btrfs_feature_attr(a);
1296 bit = ilog2(sfa->feature_bit);
1297 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
1298
1299 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
1300 }
1301
1302 for (set = 0; set < FEAT_MAX; set++) {
1303 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
1304 char *name = btrfs_unknown_feature_names[set][i];
1305 fa = &btrfs_feature_attrs[set][i];
1306
1307 if (fa->kobj_attr.attr.name)
1308 continue;
1309
1310 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u",
1311 btrfs_feature_set_names[set], i);
1312
1313 fa->kobj_attr.attr.name = name;
1314 fa->kobj_attr.attr.mode = S_IRUGO;
1315 fa->feature_set = set;
1316 fa->feature_bit = 1ULL << i;
1317 }
1318 }
1319 }
1320
1321 /*
1322 * Create a sysfs entry for a given block group type at path
1323 * /sys/fs/btrfs/UUID/allocation/data/TYPE
1324 */
btrfs_sysfs_add_block_group_type(struct btrfs_block_group * cache)1325 void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache)
1326 {
1327 struct btrfs_fs_info *fs_info = cache->fs_info;
1328 struct btrfs_space_info *space_info = cache->space_info;
1329 struct raid_kobject *rkobj;
1330 const int index = btrfs_bg_flags_to_raid_index(cache->flags);
1331 unsigned int nofs_flag;
1332 int ret;
1333
1334 /*
1335 * Setup a NOFS context because kobject_add(), deep in its call chain,
1336 * does GFP_KERNEL allocations, and we are often called in a context
1337 * where if reclaim is triggered we can deadlock (we are either holding
1338 * a transaction handle or some lock required for a transaction
1339 * commit).
1340 */
1341 nofs_flag = memalloc_nofs_save();
1342
1343 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
1344 if (!rkobj) {
1345 memalloc_nofs_restore(nofs_flag);
1346 btrfs_warn(cache->fs_info,
1347 "couldn't alloc memory for raid level kobject");
1348 return;
1349 }
1350
1351 rkobj->flags = cache->flags;
1352 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
1353
1354 /*
1355 * We call this either on mount, or if we've created a block group for a
1356 * new index type while running (i.e. when restriping). The running
1357 * case is tricky because we could race with other threads, so we need
1358 * to have this check to make sure we didn't already init the kobject.
1359 *
1360 * We don't have to protect on the free side because it only happens on
1361 * unmount.
1362 */
1363 spin_lock(&space_info->lock);
1364 if (space_info->block_group_kobjs[index]) {
1365 spin_unlock(&space_info->lock);
1366 kobject_put(&rkobj->kobj);
1367 return;
1368 } else {
1369 space_info->block_group_kobjs[index] = &rkobj->kobj;
1370 }
1371 spin_unlock(&space_info->lock);
1372
1373 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s",
1374 btrfs_bg_type_to_raid_name(rkobj->flags));
1375 memalloc_nofs_restore(nofs_flag);
1376 if (ret) {
1377 spin_lock(&space_info->lock);
1378 space_info->block_group_kobjs[index] = NULL;
1379 spin_unlock(&space_info->lock);
1380 kobject_put(&rkobj->kobj);
1381 btrfs_warn(fs_info,
1382 "failed to add kobject for block cache, ignoring");
1383 return;
1384 }
1385 }
1386
1387 /*
1388 * Remove sysfs directories for all block group types of a given space info and
1389 * the space info as well
1390 */
btrfs_sysfs_remove_space_info(struct btrfs_space_info * space_info)1391 void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
1392 {
1393 int i;
1394
1395 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1396 struct kobject *kobj;
1397
1398 kobj = space_info->block_group_kobjs[i];
1399 space_info->block_group_kobjs[i] = NULL;
1400 if (kobj) {
1401 kobject_del(kobj);
1402 kobject_put(kobj);
1403 }
1404 }
1405 kobject_del(&space_info->kobj);
1406 kobject_put(&space_info->kobj);
1407 }
1408
alloc_name(u64 flags)1409 static const char *alloc_name(u64 flags)
1410 {
1411 switch (flags) {
1412 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
1413 return "mixed";
1414 case BTRFS_BLOCK_GROUP_METADATA:
1415 return "metadata";
1416 case BTRFS_BLOCK_GROUP_DATA:
1417 return "data";
1418 case BTRFS_BLOCK_GROUP_SYSTEM:
1419 return "system";
1420 default:
1421 WARN_ON(1);
1422 return "invalid-combination";
1423 }
1424 }
1425
1426 /*
1427 * Create a sysfs entry for a space info type at path
1428 * /sys/fs/btrfs/UUID/allocation/TYPE
1429 */
btrfs_sysfs_add_space_info_type(struct btrfs_fs_info * fs_info,struct btrfs_space_info * space_info)1430 int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
1431 struct btrfs_space_info *space_info)
1432 {
1433 int ret;
1434
1435 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
1436 fs_info->space_info_kobj, "%s",
1437 alloc_name(space_info->flags));
1438 if (ret) {
1439 kobject_put(&space_info->kobj);
1440 return ret;
1441 }
1442
1443 return 0;
1444 }
1445
btrfs_sysfs_remove_device(struct btrfs_device * device)1446 void btrfs_sysfs_remove_device(struct btrfs_device *device)
1447 {
1448 struct kobject *devices_kobj;
1449
1450 /*
1451 * Seed fs_devices devices_kobj aren't used, fetch kobject from the
1452 * fs_info::fs_devices.
1453 */
1454 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1455 ASSERT(devices_kobj);
1456
1457 if (device->bdev)
1458 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
1459
1460 if (device->devid_kobj.state_initialized) {
1461 kobject_del(&device->devid_kobj);
1462 kobject_put(&device->devid_kobj);
1463 wait_for_completion(&device->kobj_unregister);
1464 }
1465 }
1466
btrfs_devinfo_in_fs_metadata_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1467 static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
1468 struct kobj_attribute *a,
1469 char *buf)
1470 {
1471 int val;
1472 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1473 devid_kobj);
1474
1475 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
1476
1477 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1478 }
1479 BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
1480
btrfs_devinfo_missing_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1481 static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
1482 struct kobj_attribute *a, char *buf)
1483 {
1484 int val;
1485 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1486 devid_kobj);
1487
1488 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1489
1490 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1491 }
1492 BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
1493
btrfs_devinfo_replace_target_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1494 static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
1495 struct kobj_attribute *a,
1496 char *buf)
1497 {
1498 int val;
1499 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1500 devid_kobj);
1501
1502 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1503
1504 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1505 }
1506 BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
1507
btrfs_devinfo_scrub_speed_max_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1508 static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
1509 struct kobj_attribute *a,
1510 char *buf)
1511 {
1512 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1513 devid_kobj);
1514
1515 return scnprintf(buf, PAGE_SIZE, "%llu\n",
1516 READ_ONCE(device->scrub_speed_max));
1517 }
1518
btrfs_devinfo_scrub_speed_max_store(struct kobject * kobj,struct kobj_attribute * a,const char * buf,size_t len)1519 static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
1520 struct kobj_attribute *a,
1521 const char *buf, size_t len)
1522 {
1523 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1524 devid_kobj);
1525 char *endptr;
1526 unsigned long long limit;
1527
1528 limit = memparse(buf, &endptr);
1529 /* There could be trailing '\n', also catch any typos after the value. */
1530 endptr = skip_spaces(endptr);
1531 if (*endptr != 0)
1532 return -EINVAL;
1533 WRITE_ONCE(device->scrub_speed_max, limit);
1534 return len;
1535 }
1536 BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show,
1537 btrfs_devinfo_scrub_speed_max_store);
1538
btrfs_devinfo_writeable_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1539 static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
1540 struct kobj_attribute *a, char *buf)
1541 {
1542 int val;
1543 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1544 devid_kobj);
1545
1546 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1547
1548 return scnprintf(buf, PAGE_SIZE, "%d\n", val);
1549 }
1550 BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
1551
btrfs_devinfo_error_stats_show(struct kobject * kobj,struct kobj_attribute * a,char * buf)1552 static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
1553 struct kobj_attribute *a, char *buf)
1554 {
1555 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1556 devid_kobj);
1557
1558 if (!device->dev_stats_valid)
1559 return scnprintf(buf, PAGE_SIZE, "invalid\n");
1560
1561 /*
1562 * Print all at once so we get a snapshot of all values from the same
1563 * time. Keep them in sync and in order of definition of
1564 * btrfs_dev_stat_values.
1565 */
1566 return scnprintf(buf, PAGE_SIZE,
1567 "write_errs %d\n"
1568 "read_errs %d\n"
1569 "flush_errs %d\n"
1570 "corruption_errs %d\n"
1571 "generation_errs %d\n",
1572 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS),
1573 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS),
1574 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS),
1575 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS),
1576 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS));
1577 }
1578 BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show);
1579
1580 /*
1581 * Information about one device.
1582 *
1583 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/
1584 */
1585 static struct attribute *devid_attrs[] = {
1586 BTRFS_ATTR_PTR(devid, error_stats),
1587 BTRFS_ATTR_PTR(devid, in_fs_metadata),
1588 BTRFS_ATTR_PTR(devid, missing),
1589 BTRFS_ATTR_PTR(devid, replace_target),
1590 BTRFS_ATTR_PTR(devid, scrub_speed_max),
1591 BTRFS_ATTR_PTR(devid, writeable),
1592 NULL
1593 };
1594 ATTRIBUTE_GROUPS(devid);
1595
btrfs_release_devid_kobj(struct kobject * kobj)1596 static void btrfs_release_devid_kobj(struct kobject *kobj)
1597 {
1598 struct btrfs_device *device = container_of(kobj, struct btrfs_device,
1599 devid_kobj);
1600
1601 memset(&device->devid_kobj, 0, sizeof(struct kobject));
1602 complete(&device->kobj_unregister);
1603 }
1604
1605 static struct kobj_type devid_ktype = {
1606 .sysfs_ops = &kobj_sysfs_ops,
1607 .default_groups = devid_groups,
1608 .release = btrfs_release_devid_kobj,
1609 };
1610
btrfs_sysfs_add_device(struct btrfs_device * device)1611 int btrfs_sysfs_add_device(struct btrfs_device *device)
1612 {
1613 int ret;
1614 unsigned int nofs_flag;
1615 struct kobject *devices_kobj;
1616 struct kobject *devinfo_kobj;
1617
1618 /*
1619 * Make sure we use the fs_info::fs_devices to fetch the kobjects even
1620 * for the seed fs_devices
1621 */
1622 devices_kobj = device->fs_info->fs_devices->devices_kobj;
1623 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
1624 ASSERT(devices_kobj);
1625 ASSERT(devinfo_kobj);
1626
1627 nofs_flag = memalloc_nofs_save();
1628
1629 if (device->bdev) {
1630 struct kobject *disk_kobj = bdev_kobj(device->bdev);
1631
1632 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
1633 if (ret) {
1634 btrfs_warn(device->fs_info,
1635 "creating sysfs device link for devid %llu failed: %d",
1636 device->devid, ret);
1637 goto out;
1638 }
1639 }
1640
1641 init_completion(&device->kobj_unregister);
1642 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
1643 devinfo_kobj, "%llu", device->devid);
1644 if (ret) {
1645 kobject_put(&device->devid_kobj);
1646 btrfs_warn(device->fs_info,
1647 "devinfo init for devid %llu failed: %d",
1648 device->devid, ret);
1649 }
1650
1651 out:
1652 memalloc_nofs_restore(nofs_flag);
1653 return ret;
1654 }
1655
btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices * fs_devices)1656 static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices)
1657 {
1658 int ret;
1659 struct btrfs_device *device;
1660 struct btrfs_fs_devices *seed;
1661
1662 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1663 ret = btrfs_sysfs_add_device(device);
1664 if (ret)
1665 goto fail;
1666 }
1667
1668 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) {
1669 list_for_each_entry(device, &seed->devices, dev_list) {
1670 ret = btrfs_sysfs_add_device(device);
1671 if (ret)
1672 goto fail;
1673 }
1674 }
1675
1676 return 0;
1677
1678 fail:
1679 btrfs_sysfs_remove_fs_devices(fs_devices);
1680 return ret;
1681 }
1682
btrfs_kobject_uevent(struct block_device * bdev,enum kobject_action action)1683 void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
1684 {
1685 int ret;
1686
1687 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
1688 if (ret)
1689 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
1690 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
1691 &disk_to_dev(bdev->bd_disk)->kobj);
1692 }
1693
btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices * fs_devices)1694 void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices)
1695
1696 {
1697 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
1698
1699 /*
1700 * Sprouting changes fsid of the mounted filesystem, rename the fsid
1701 * directory
1702 */
1703 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid);
1704 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf))
1705 btrfs_warn(fs_devices->fs_info,
1706 "sysfs: failed to create fsid for sprout");
1707 }
1708
btrfs_sysfs_update_devid(struct btrfs_device * device)1709 void btrfs_sysfs_update_devid(struct btrfs_device *device)
1710 {
1711 char tmp[24];
1712
1713 snprintf(tmp, sizeof(tmp), "%llu", device->devid);
1714
1715 if (kobject_rename(&device->devid_kobj, tmp))
1716 btrfs_warn(device->fs_devices->fs_info,
1717 "sysfs: failed to update devid for %llu",
1718 device->devid);
1719 }
1720
1721 /* /sys/fs/btrfs/ entry */
1722 static struct kset *btrfs_kset;
1723
1724 /*
1725 * Creates:
1726 * /sys/fs/btrfs/UUID
1727 *
1728 * Can be called by the device discovery thread.
1729 */
btrfs_sysfs_add_fsid(struct btrfs_fs_devices * fs_devs)1730 int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
1731 {
1732 int error;
1733
1734 init_completion(&fs_devs->kobj_unregister);
1735 fs_devs->fsid_kobj.kset = btrfs_kset;
1736 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
1737 "%pU", fs_devs->fsid);
1738 if (error) {
1739 kobject_put(&fs_devs->fsid_kobj);
1740 return error;
1741 }
1742
1743 fs_devs->devices_kobj = kobject_create_and_add("devices",
1744 &fs_devs->fsid_kobj);
1745 if (!fs_devs->devices_kobj) {
1746 btrfs_err(fs_devs->fs_info,
1747 "failed to init sysfs device interface");
1748 btrfs_sysfs_remove_fsid(fs_devs);
1749 return -ENOMEM;
1750 }
1751
1752 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo",
1753 &fs_devs->fsid_kobj);
1754 if (!fs_devs->devinfo_kobj) {
1755 btrfs_err(fs_devs->fs_info,
1756 "failed to init sysfs devinfo kobject");
1757 btrfs_sysfs_remove_fsid(fs_devs);
1758 return -ENOMEM;
1759 }
1760
1761 return 0;
1762 }
1763
btrfs_sysfs_add_mounted(struct btrfs_fs_info * fs_info)1764 int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
1765 {
1766 int error;
1767 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
1768 struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
1769
1770 error = btrfs_sysfs_add_fs_devices(fs_devs);
1771 if (error)
1772 return error;
1773
1774 error = sysfs_create_files(fsid_kobj, btrfs_attrs);
1775 if (error) {
1776 btrfs_sysfs_remove_fs_devices(fs_devs);
1777 return error;
1778 }
1779
1780 error = sysfs_create_group(fsid_kobj,
1781 &btrfs_feature_attr_group);
1782 if (error)
1783 goto failure;
1784
1785 #ifdef CONFIG_BTRFS_DEBUG
1786 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
1787 if (!fs_info->debug_kobj) {
1788 error = -ENOMEM;
1789 goto failure;
1790 }
1791
1792 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
1793 if (error)
1794 goto failure;
1795
1796 /* Discard directory */
1797 fs_info->discard_debug_kobj = kobject_create_and_add("discard",
1798 fs_info->debug_kobj);
1799 if (!fs_info->discard_debug_kobj) {
1800 error = -ENOMEM;
1801 goto failure;
1802 }
1803
1804 error = sysfs_create_files(fs_info->discard_debug_kobj,
1805 discard_debug_attrs);
1806 if (error)
1807 goto failure;
1808 #endif
1809
1810 error = addrm_unknown_feature_attrs(fs_info, true);
1811 if (error)
1812 goto failure;
1813
1814 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
1815 if (error)
1816 goto failure;
1817
1818 fs_info->space_info_kobj = kobject_create_and_add("allocation",
1819 fsid_kobj);
1820 if (!fs_info->space_info_kobj) {
1821 error = -ENOMEM;
1822 goto failure;
1823 }
1824
1825 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
1826 if (error)
1827 goto failure;
1828
1829 return 0;
1830 failure:
1831 btrfs_sysfs_remove_mounted(fs_info);
1832 return error;
1833 }
1834
qgroup_kobj_to_fs_info(struct kobject * kobj)1835 static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
1836 {
1837 return to_fs_info(kobj->parent->parent);
1838 }
1839
1840 #define QGROUP_ATTR(_member, _show_name) \
1841 static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
1842 struct kobj_attribute *a, \
1843 char *buf) \
1844 { \
1845 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1846 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1847 struct btrfs_qgroup, kobj); \
1848 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \
1849 } \
1850 BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member)
1851
1852 #define QGROUP_RSV_ATTR(_name, _type) \
1853 static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \
1854 struct kobj_attribute *a, \
1855 char *buf) \
1856 { \
1857 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \
1858 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
1859 struct btrfs_qgroup, kobj); \
1860 return btrfs_show_u64(&qgroup->rsv.values[_type], \
1861 &fs_info->qgroup_lock, buf); \
1862 } \
1863 BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
1864
1865 QGROUP_ATTR(rfer, referenced);
1866 QGROUP_ATTR(excl, exclusive);
1867 QGROUP_ATTR(max_rfer, max_referenced);
1868 QGROUP_ATTR(max_excl, max_exclusive);
1869 QGROUP_ATTR(lim_flags, limit_flags);
1870 QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
1871 QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
1872 QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
1873
1874 /*
1875 * Qgroup information.
1876 *
1877 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/
1878 */
1879 static struct attribute *qgroup_attrs[] = {
1880 BTRFS_ATTR_PTR(qgroup, referenced),
1881 BTRFS_ATTR_PTR(qgroup, exclusive),
1882 BTRFS_ATTR_PTR(qgroup, max_referenced),
1883 BTRFS_ATTR_PTR(qgroup, max_exclusive),
1884 BTRFS_ATTR_PTR(qgroup, limit_flags),
1885 BTRFS_ATTR_PTR(qgroup, rsv_data),
1886 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
1887 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
1888 NULL
1889 };
1890 ATTRIBUTE_GROUPS(qgroup);
1891
qgroup_release(struct kobject * kobj)1892 static void qgroup_release(struct kobject *kobj)
1893 {
1894 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj);
1895
1896 memset(&qgroup->kobj, 0, sizeof(*kobj));
1897 }
1898
1899 static struct kobj_type qgroup_ktype = {
1900 .sysfs_ops = &kobj_sysfs_ops,
1901 .release = qgroup_release,
1902 .default_groups = qgroup_groups,
1903 };
1904
btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info * fs_info,struct btrfs_qgroup * qgroup)1905 int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
1906 struct btrfs_qgroup *qgroup)
1907 {
1908 struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
1909 int ret;
1910
1911 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1912 return 0;
1913 if (qgroup->kobj.state_initialized)
1914 return 0;
1915 if (!qgroups_kobj)
1916 return -EINVAL;
1917
1918 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
1919 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid),
1920 btrfs_qgroup_subvolid(qgroup->qgroupid));
1921 if (ret < 0)
1922 kobject_put(&qgroup->kobj);
1923
1924 return ret;
1925 }
1926
btrfs_sysfs_del_qgroups(struct btrfs_fs_info * fs_info)1927 void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
1928 {
1929 struct btrfs_qgroup *qgroup;
1930 struct btrfs_qgroup *next;
1931
1932 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1933 return;
1934
1935 rbtree_postorder_for_each_entry_safe(qgroup, next,
1936 &fs_info->qgroup_tree, node)
1937 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1938 if (fs_info->qgroups_kobj) {
1939 kobject_del(fs_info->qgroups_kobj);
1940 kobject_put(fs_info->qgroups_kobj);
1941 fs_info->qgroups_kobj = NULL;
1942 }
1943 }
1944
1945 /* Called when qgroups get initialized, thus there is no need for locking */
btrfs_sysfs_add_qgroups(struct btrfs_fs_info * fs_info)1946 int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
1947 {
1948 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
1949 struct btrfs_qgroup *qgroup;
1950 struct btrfs_qgroup *next;
1951 int ret = 0;
1952
1953 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1954 return 0;
1955
1956 ASSERT(fsid_kobj);
1957 if (fs_info->qgroups_kobj)
1958 return 0;
1959
1960 fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj);
1961 if (!fs_info->qgroups_kobj) {
1962 ret = -ENOMEM;
1963 goto out;
1964 }
1965 rbtree_postorder_for_each_entry_safe(qgroup, next,
1966 &fs_info->qgroup_tree, node) {
1967 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1968 if (ret < 0)
1969 goto out;
1970 }
1971
1972 out:
1973 if (ret < 0)
1974 btrfs_sysfs_del_qgroups(fs_info);
1975 return ret;
1976 }
1977
btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info * fs_info,struct btrfs_qgroup * qgroup)1978 void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
1979 struct btrfs_qgroup *qgroup)
1980 {
1981 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
1982 return;
1983
1984 if (qgroup->kobj.state_initialized) {
1985 kobject_del(&qgroup->kobj);
1986 kobject_put(&qgroup->kobj);
1987 }
1988 }
1989
1990 /*
1991 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
1992 * values in superblock. Call after any changes to incompat/compat_ro flags
1993 */
btrfs_sysfs_feature_update(struct btrfs_fs_info * fs_info,u64 bit,enum btrfs_feature_set set)1994 void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
1995 u64 bit, enum btrfs_feature_set set)
1996 {
1997 struct btrfs_fs_devices *fs_devs;
1998 struct kobject *fsid_kobj;
1999 u64 __maybe_unused features;
2000 int __maybe_unused ret;
2001
2002 if (!fs_info)
2003 return;
2004
2005 /*
2006 * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not
2007 * safe when called from some contexts (eg. balance)
2008 */
2009 features = get_features(fs_info, set);
2010 ASSERT(bit & supported_feature_masks[set]);
2011
2012 fs_devs = fs_info->fs_devices;
2013 fsid_kobj = &fs_devs->fsid_kobj;
2014
2015 if (!fsid_kobj->state_initialized)
2016 return;
2017
2018 /*
2019 * FIXME: this is too heavy to update just one value, ideally we'd like
2020 * to use sysfs_update_group but some refactoring is needed first.
2021 */
2022 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
2023 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
2024 }
2025
btrfs_init_sysfs(void)2026 int __init btrfs_init_sysfs(void)
2027 {
2028 int ret;
2029
2030 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
2031 if (!btrfs_kset)
2032 return -ENOMEM;
2033
2034 init_feature_attrs();
2035 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2036 if (ret)
2037 goto out2;
2038 ret = sysfs_merge_group(&btrfs_kset->kobj,
2039 &btrfs_static_feature_attr_group);
2040 if (ret)
2041 goto out_remove_group;
2042
2043 #ifdef CONFIG_BTRFS_DEBUG
2044 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2045 if (ret) {
2046 sysfs_unmerge_group(&btrfs_kset->kobj,
2047 &btrfs_static_feature_attr_group);
2048 goto out_remove_group;
2049 }
2050 #endif
2051
2052 return 0;
2053
2054 out_remove_group:
2055 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2056 out2:
2057 kset_unregister(btrfs_kset);
2058
2059 return ret;
2060 }
2061
btrfs_exit_sysfs(void)2062 void __cold btrfs_exit_sysfs(void)
2063 {
2064 sysfs_unmerge_group(&btrfs_kset->kobj,
2065 &btrfs_static_feature_attr_group);
2066 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
2067 #ifdef CONFIG_BTRFS_DEBUG
2068 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
2069 #endif
2070 kset_unregister(btrfs_kset);
2071 }
2072
2073