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 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 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 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 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 } 107 108 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 } 175 176 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 }; 226 227 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 } 237 238 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, 0444, global_rsv_size_show); 246 247 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, 0444, global_rsv_reserved_show); 255 256 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj) 257 258 static ssize_t raid_bytes_show(struct kobject *kobj, 259 struct kobj_attribute *attr, char *buf); 260 BTRFS_RAID_ATTR(total_bytes, raid_bytes_show); 261 BTRFS_RAID_ATTR(used_bytes, raid_bytes_show); 262 263 static ssize_t raid_bytes_show(struct kobject *kobj, 264 struct kobj_attribute *attr, char *buf) 265 266 { 267 struct btrfs_space_info *sinfo = to_space_info(kobj->parent); 268 struct btrfs_block_group_cache *block_group; 269 int index = kobj - sinfo->block_group_kobjs; 270 u64 val = 0; 271 272 down_read(&sinfo->groups_sem); 273 list_for_each_entry(block_group, &sinfo->block_groups[index], list) { 274 if (&attr->attr == BTRFS_RAID_ATTR_PTR(total_bytes)) 275 val += block_group->key.offset; 276 else 277 val += btrfs_block_group_used(&block_group->item); 278 } 279 up_read(&sinfo->groups_sem); 280 return snprintf(buf, PAGE_SIZE, "%llu\n", val); 281 } 282 283 static struct attribute *raid_attributes[] = { 284 BTRFS_RAID_ATTR_PTR(total_bytes), 285 BTRFS_RAID_ATTR_PTR(used_bytes), 286 NULL 287 }; 288 289 static void release_raid_kobj(struct kobject *kobj) 290 { 291 kobject_put(kobj->parent); 292 } 293 294 struct kobj_type btrfs_raid_ktype = { 295 .sysfs_ops = &kobj_sysfs_ops, 296 .release = release_raid_kobj, 297 .default_attrs = raid_attributes, 298 }; 299 300 #define SPACE_INFO_ATTR(field) \ 301 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \ 302 struct kobj_attribute *a, \ 303 char *buf) \ 304 { \ 305 struct btrfs_space_info *sinfo = to_space_info(kobj); \ 306 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \ 307 } \ 308 BTRFS_ATTR(field, 0444, btrfs_space_info_show_##field) 309 310 static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj, 311 struct kobj_attribute *a, 312 char *buf) 313 { 314 struct btrfs_space_info *sinfo = to_space_info(kobj); 315 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned); 316 return snprintf(buf, PAGE_SIZE, "%lld\n", val); 317 } 318 319 SPACE_INFO_ATTR(flags); 320 SPACE_INFO_ATTR(total_bytes); 321 SPACE_INFO_ATTR(bytes_used); 322 SPACE_INFO_ATTR(bytes_pinned); 323 SPACE_INFO_ATTR(bytes_reserved); 324 SPACE_INFO_ATTR(bytes_may_use); 325 SPACE_INFO_ATTR(disk_used); 326 SPACE_INFO_ATTR(disk_total); 327 BTRFS_ATTR(total_bytes_pinned, 0444, btrfs_space_info_show_total_bytes_pinned); 328 329 static struct attribute *space_info_attrs[] = { 330 BTRFS_ATTR_PTR(flags), 331 BTRFS_ATTR_PTR(total_bytes), 332 BTRFS_ATTR_PTR(bytes_used), 333 BTRFS_ATTR_PTR(bytes_pinned), 334 BTRFS_ATTR_PTR(bytes_reserved), 335 BTRFS_ATTR_PTR(bytes_may_use), 336 BTRFS_ATTR_PTR(disk_used), 337 BTRFS_ATTR_PTR(disk_total), 338 BTRFS_ATTR_PTR(total_bytes_pinned), 339 NULL, 340 }; 341 342 static void space_info_release(struct kobject *kobj) 343 { 344 struct btrfs_space_info *sinfo = to_space_info(kobj); 345 percpu_counter_destroy(&sinfo->total_bytes_pinned); 346 kfree(sinfo); 347 } 348 349 struct kobj_type space_info_ktype = { 350 .sysfs_ops = &kobj_sysfs_ops, 351 .release = space_info_release, 352 .default_attrs = space_info_attrs, 353 }; 354 355 static const struct attribute *allocation_attrs[] = { 356 BTRFS_ATTR_PTR(global_rsv_reserved), 357 BTRFS_ATTR_PTR(global_rsv_size), 358 NULL, 359 }; 360 361 static ssize_t btrfs_label_show(struct kobject *kobj, 362 struct kobj_attribute *a, char *buf) 363 { 364 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 365 return snprintf(buf, PAGE_SIZE, "%s\n", fs_info->super_copy->label); 366 } 367 368 static ssize_t btrfs_label_store(struct kobject *kobj, 369 struct kobj_attribute *a, 370 const char *buf, size_t len) 371 { 372 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 373 struct btrfs_trans_handle *trans; 374 struct btrfs_root *root = fs_info->fs_root; 375 int ret; 376 377 if (len >= BTRFS_LABEL_SIZE) { 378 pr_err("BTRFS: unable to set label with more than %d bytes\n", 379 BTRFS_LABEL_SIZE - 1); 380 return -EINVAL; 381 } 382 383 trans = btrfs_start_transaction(root, 0); 384 if (IS_ERR(trans)) 385 return PTR_ERR(trans); 386 387 spin_lock(&root->fs_info->super_lock); 388 strcpy(fs_info->super_copy->label, buf); 389 spin_unlock(&root->fs_info->super_lock); 390 ret = btrfs_commit_transaction(trans, root); 391 392 if (!ret) 393 return len; 394 395 return ret; 396 } 397 BTRFS_ATTR_RW(label, 0644, btrfs_label_show, btrfs_label_store); 398 399 static struct attribute *btrfs_attrs[] = { 400 BTRFS_ATTR_PTR(label), 401 NULL, 402 }; 403 404 static void btrfs_release_super_kobj(struct kobject *kobj) 405 { 406 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 407 complete(&fs_info->kobj_unregister); 408 } 409 410 static struct kobj_type btrfs_ktype = { 411 .sysfs_ops = &kobj_sysfs_ops, 412 .release = btrfs_release_super_kobj, 413 .default_attrs = btrfs_attrs, 414 }; 415 416 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj) 417 { 418 if (kobj->ktype != &btrfs_ktype) 419 return NULL; 420 return container_of(kobj, struct btrfs_fs_info, super_kobj); 421 } 422 423 #define NUM_FEATURE_BITS 64 424 static char btrfs_unknown_feature_names[3][NUM_FEATURE_BITS][13]; 425 static struct btrfs_feature_attr btrfs_feature_attrs[3][NUM_FEATURE_BITS]; 426 427 static u64 supported_feature_masks[3] = { 428 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP, 429 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP, 430 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP, 431 }; 432 433 static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add) 434 { 435 int set; 436 437 for (set = 0; set < FEAT_MAX; set++) { 438 int i; 439 struct attribute *attrs[2]; 440 struct attribute_group agroup = { 441 .name = "features", 442 .attrs = attrs, 443 }; 444 u64 features = get_features(fs_info, set); 445 features &= ~supported_feature_masks[set]; 446 447 if (!features) 448 continue; 449 450 attrs[1] = NULL; 451 for (i = 0; i < NUM_FEATURE_BITS; i++) { 452 struct btrfs_feature_attr *fa; 453 454 if (!(features & (1ULL << i))) 455 continue; 456 457 fa = &btrfs_feature_attrs[set][i]; 458 attrs[0] = &fa->kobj_attr.attr; 459 if (add) { 460 int ret; 461 ret = sysfs_merge_group(&fs_info->super_kobj, 462 &agroup); 463 if (ret) 464 return ret; 465 } else 466 sysfs_unmerge_group(&fs_info->super_kobj, 467 &agroup); 468 } 469 470 } 471 return 0; 472 } 473 474 static void __btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info) 475 { 476 kobject_del(&fs_info->super_kobj); 477 kobject_put(&fs_info->super_kobj); 478 wait_for_completion(&fs_info->kobj_unregister); 479 } 480 481 void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info) 482 { 483 if (fs_info->space_info_kobj) { 484 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); 485 kobject_del(fs_info->space_info_kobj); 486 kobject_put(fs_info->space_info_kobj); 487 } 488 kobject_del(fs_info->device_dir_kobj); 489 kobject_put(fs_info->device_dir_kobj); 490 addrm_unknown_feature_attrs(fs_info, false); 491 sysfs_remove_group(&fs_info->super_kobj, &btrfs_feature_attr_group); 492 __btrfs_sysfs_remove_one(fs_info); 493 } 494 495 const char * const btrfs_feature_set_names[3] = { 496 [FEAT_COMPAT] = "compat", 497 [FEAT_COMPAT_RO] = "compat_ro", 498 [FEAT_INCOMPAT] = "incompat", 499 }; 500 501 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags) 502 { 503 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */ 504 int len = 0; 505 int i; 506 char *str; 507 508 str = kmalloc(bufsize, GFP_KERNEL); 509 if (!str) 510 return str; 511 512 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 513 const char *name; 514 515 if (!(flags & (1ULL << i))) 516 continue; 517 518 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name; 519 len += snprintf(str + len, bufsize - len, "%s%s", 520 len ? "," : "", name); 521 } 522 523 return str; 524 } 525 526 static void init_feature_attrs(void) 527 { 528 struct btrfs_feature_attr *fa; 529 int set, i; 530 531 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) != 532 ARRAY_SIZE(btrfs_feature_attrs)); 533 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) != 534 ARRAY_SIZE(btrfs_feature_attrs[0])); 535 536 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs)); 537 memset(btrfs_unknown_feature_names, 0, 538 sizeof(btrfs_unknown_feature_names)); 539 540 for (i = 0; btrfs_supported_feature_attrs[i]; i++) { 541 struct btrfs_feature_attr *sfa; 542 struct attribute *a = btrfs_supported_feature_attrs[i]; 543 int bit; 544 sfa = attr_to_btrfs_feature_attr(a); 545 bit = ilog2(sfa->feature_bit); 546 fa = &btrfs_feature_attrs[sfa->feature_set][bit]; 547 548 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name; 549 } 550 551 for (set = 0; set < FEAT_MAX; set++) { 552 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 553 char *name = btrfs_unknown_feature_names[set][i]; 554 fa = &btrfs_feature_attrs[set][i]; 555 556 if (fa->kobj_attr.attr.name) 557 continue; 558 559 snprintf(name, 13, "%s:%u", 560 btrfs_feature_set_names[set], i); 561 562 fa->kobj_attr.attr.name = name; 563 fa->kobj_attr.attr.mode = S_IRUGO; 564 fa->feature_set = set; 565 fa->feature_bit = 1ULL << i; 566 } 567 } 568 } 569 570 static int add_device_membership(struct btrfs_fs_info *fs_info) 571 { 572 int error = 0; 573 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 574 struct btrfs_device *dev; 575 576 fs_info->device_dir_kobj = kobject_create_and_add("devices", 577 &fs_info->super_kobj); 578 if (!fs_info->device_dir_kobj) 579 return -ENOMEM; 580 581 list_for_each_entry(dev, &fs_devices->devices, dev_list) { 582 struct hd_struct *disk; 583 struct kobject *disk_kobj; 584 585 if (!dev->bdev) 586 continue; 587 588 disk = dev->bdev->bd_part; 589 disk_kobj = &part_to_dev(disk)->kobj; 590 591 error = sysfs_create_link(fs_info->device_dir_kobj, 592 disk_kobj, disk_kobj->name); 593 if (error) 594 break; 595 } 596 597 return error; 598 } 599 600 /* /sys/fs/btrfs/ entry */ 601 static struct kset *btrfs_kset; 602 603 /* /sys/kernel/debug/btrfs */ 604 static struct dentry *btrfs_debugfs_root_dentry; 605 606 /* Debugging tunables and exported data */ 607 u64 btrfs_debugfs_test; 608 609 int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info) 610 { 611 int error; 612 613 init_completion(&fs_info->kobj_unregister); 614 fs_info->super_kobj.kset = btrfs_kset; 615 error = kobject_init_and_add(&fs_info->super_kobj, &btrfs_ktype, NULL, 616 "%pU", fs_info->fsid); 617 if (error) 618 return error; 619 620 error = sysfs_create_group(&fs_info->super_kobj, 621 &btrfs_feature_attr_group); 622 if (error) { 623 __btrfs_sysfs_remove_one(fs_info); 624 return error; 625 } 626 627 error = addrm_unknown_feature_attrs(fs_info, true); 628 if (error) 629 goto failure; 630 631 error = add_device_membership(fs_info); 632 if (error) 633 goto failure; 634 635 fs_info->space_info_kobj = kobject_create_and_add("allocation", 636 &fs_info->super_kobj); 637 if (!fs_info->space_info_kobj) { 638 error = -ENOMEM; 639 goto failure; 640 } 641 642 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs); 643 if (error) 644 goto failure; 645 646 return 0; 647 failure: 648 btrfs_sysfs_remove_one(fs_info); 649 return error; 650 } 651 652 static int btrfs_init_debugfs(void) 653 { 654 #ifdef CONFIG_DEBUG_FS 655 btrfs_debugfs_root_dentry = debugfs_create_dir("btrfs", NULL); 656 if (!btrfs_debugfs_root_dentry) 657 return -ENOMEM; 658 659 debugfs_create_u64("test", S_IRUGO | S_IWUGO, btrfs_debugfs_root_dentry, 660 &btrfs_debugfs_test); 661 #endif 662 return 0; 663 } 664 665 int btrfs_init_sysfs(void) 666 { 667 int ret; 668 669 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); 670 if (!btrfs_kset) 671 return -ENOMEM; 672 673 ret = btrfs_init_debugfs(); 674 if (ret) 675 return ret; 676 677 init_feature_attrs(); 678 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 679 680 return ret; 681 } 682 683 void btrfs_exit_sysfs(void) 684 { 685 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 686 kset_unregister(btrfs_kset); 687 debugfs_remove_recursive(btrfs_debugfs_root_dentry); 688 } 689 690