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