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 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 } 100 101 static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr) 102 { 103 return container_of(attr, struct kobj_attribute, attr); 104 } 105 106 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 } 111 112 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 } 123 124 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 } 135 136 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 } 166 167 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 sysfs_emit(buf, "%d\n", val); 181 } 182 183 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 } 250 251 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 }; 332 333 static ssize_t rmdir_subvol_show(struct kobject *kobj, 334 struct kobj_attribute *ka, char *buf) 335 { 336 return sysfs_emit(buf, "0\n"); 337 } 338 BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show); 339 340 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 += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "), 352 btrfs_super_csum_name(i)); 353 354 } 355 356 ret += sysfs_emit_at(buf, ret, "\n"); 357 return ret; 358 } 359 BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show); 360 361 static ssize_t send_stream_version_show(struct kobject *kobj, 362 struct kobj_attribute *ka, char *buf) 363 { 364 return sysfs_emit(buf, "%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 }; 375 376 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 += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]); 385 ret += sysfs_emit_at(buf, ret, "\n"); 386 return ret; 387 } 388 BTRFS_ATTR(static_feature, supported_rescue_options, 389 supported_rescue_options_show); 390 391 static ssize_t supported_sectorsizes_show(struct kobject *kobj, 392 struct kobj_attribute *a, 393 char *buf) 394 { 395 ssize_t ret = 0; 396 397 /* 4K sector size is also supported with 64K page size */ 398 if (PAGE_SIZE == SZ_64K) 399 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K); 400 401 /* Only sectorsize == PAGE_SIZE is now supported */ 402 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE); 403 404 return ret; 405 } 406 BTRFS_ATTR(static_feature, supported_sectorsizes, 407 supported_sectorsizes_show); 408 409 /* 410 * Features which only depend on kernel version. 411 * 412 * These are listed in /sys/fs/btrfs/features along with 413 * btrfs_supported_feature_attrs. 414 */ 415 static struct attribute *btrfs_supported_static_feature_attrs[] = { 416 BTRFS_ATTR_PTR(static_feature, rmdir_subvol), 417 BTRFS_ATTR_PTR(static_feature, supported_checksums), 418 BTRFS_ATTR_PTR(static_feature, send_stream_version), 419 BTRFS_ATTR_PTR(static_feature, supported_rescue_options), 420 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes), 421 NULL 422 }; 423 424 static const struct attribute_group btrfs_static_feature_attr_group = { 425 .name = "features", 426 .attrs = btrfs_supported_static_feature_attrs, 427 }; 428 429 #ifdef CONFIG_BTRFS_DEBUG 430 431 /* 432 * Discard statistics and tunables 433 */ 434 #define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent) 435 436 static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj, 437 struct kobj_attribute *a, 438 char *buf) 439 { 440 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 441 442 return sysfs_emit(buf, "%lld\n", 443 atomic64_read(&fs_info->discard_ctl.discardable_bytes)); 444 } 445 BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show); 446 447 static ssize_t btrfs_discardable_extents_show(struct kobject *kobj, 448 struct kobj_attribute *a, 449 char *buf) 450 { 451 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 452 453 return sysfs_emit(buf, "%d\n", 454 atomic_read(&fs_info->discard_ctl.discardable_extents)); 455 } 456 BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show); 457 458 static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj, 459 struct kobj_attribute *a, 460 char *buf) 461 { 462 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 463 464 return sysfs_emit(buf, "%llu\n", 465 fs_info->discard_ctl.discard_bitmap_bytes); 466 } 467 BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show); 468 469 static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj, 470 struct kobj_attribute *a, 471 char *buf) 472 { 473 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 474 475 return sysfs_emit(buf, "%lld\n", 476 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved)); 477 } 478 BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show); 479 480 static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj, 481 struct kobj_attribute *a, 482 char *buf) 483 { 484 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 485 486 return sysfs_emit(buf, "%llu\n", 487 fs_info->discard_ctl.discard_extent_bytes); 488 } 489 BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show); 490 491 static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj, 492 struct kobj_attribute *a, 493 char *buf) 494 { 495 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 496 497 return sysfs_emit(buf, "%u\n", 498 READ_ONCE(fs_info->discard_ctl.iops_limit)); 499 } 500 501 static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj, 502 struct kobj_attribute *a, 503 const char *buf, size_t len) 504 { 505 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 506 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 507 u32 iops_limit; 508 int ret; 509 510 ret = kstrtou32(buf, 10, &iops_limit); 511 if (ret) 512 return -EINVAL; 513 514 WRITE_ONCE(discard_ctl->iops_limit, iops_limit); 515 btrfs_discard_calc_delay(discard_ctl); 516 btrfs_discard_schedule_work(discard_ctl, true); 517 return len; 518 } 519 BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show, 520 btrfs_discard_iops_limit_store); 521 522 static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj, 523 struct kobj_attribute *a, 524 char *buf) 525 { 526 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 527 528 return sysfs_emit(buf, "%u\n", 529 READ_ONCE(fs_info->discard_ctl.kbps_limit)); 530 } 531 532 static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj, 533 struct kobj_attribute *a, 534 const char *buf, size_t len) 535 { 536 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 537 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 538 u32 kbps_limit; 539 int ret; 540 541 ret = kstrtou32(buf, 10, &kbps_limit); 542 if (ret) 543 return -EINVAL; 544 545 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit); 546 btrfs_discard_schedule_work(discard_ctl, true); 547 return len; 548 } 549 BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show, 550 btrfs_discard_kbps_limit_store); 551 552 static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj, 553 struct kobj_attribute *a, 554 char *buf) 555 { 556 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 557 558 return sysfs_emit(buf, "%llu\n", 559 READ_ONCE(fs_info->discard_ctl.max_discard_size)); 560 } 561 562 static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj, 563 struct kobj_attribute *a, 564 const char *buf, size_t len) 565 { 566 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 567 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 568 u64 max_discard_size; 569 int ret; 570 571 ret = kstrtou64(buf, 10, &max_discard_size); 572 if (ret) 573 return -EINVAL; 574 575 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size); 576 577 return len; 578 } 579 BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show, 580 btrfs_discard_max_discard_size_store); 581 582 /* 583 * Per-filesystem debugging of discard (when mounted with discard=async). 584 * 585 * Path: /sys/fs/btrfs/<uuid>/debug/discard/ 586 */ 587 static const struct attribute *discard_debug_attrs[] = { 588 BTRFS_ATTR_PTR(discard, discardable_bytes), 589 BTRFS_ATTR_PTR(discard, discardable_extents), 590 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes), 591 BTRFS_ATTR_PTR(discard, discard_bytes_saved), 592 BTRFS_ATTR_PTR(discard, discard_extent_bytes), 593 BTRFS_ATTR_PTR(discard, iops_limit), 594 BTRFS_ATTR_PTR(discard, kbps_limit), 595 BTRFS_ATTR_PTR(discard, max_discard_size), 596 NULL, 597 }; 598 599 /* 600 * Per-filesystem runtime debugging exported via sysfs. 601 * 602 * Path: /sys/fs/btrfs/UUID/debug/ 603 */ 604 static const struct attribute *btrfs_debug_mount_attrs[] = { 605 NULL, 606 }; 607 608 /* 609 * Runtime debugging exported via sysfs, applies to all mounted filesystems. 610 * 611 * Path: /sys/fs/btrfs/debug 612 */ 613 static struct attribute *btrfs_debug_feature_attrs[] = { 614 NULL 615 }; 616 617 static const struct attribute_group btrfs_debug_feature_attr_group = { 618 .name = "debug", 619 .attrs = btrfs_debug_feature_attrs, 620 }; 621 622 #endif 623 624 static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf) 625 { 626 u64 val; 627 if (lock) 628 spin_lock(lock); 629 val = *value_ptr; 630 if (lock) 631 spin_unlock(lock); 632 return sysfs_emit(buf, "%llu\n", val); 633 } 634 635 static ssize_t global_rsv_size_show(struct kobject *kobj, 636 struct kobj_attribute *ka, char *buf) 637 { 638 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); 639 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 640 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf); 641 } 642 BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show); 643 644 static ssize_t global_rsv_reserved_show(struct kobject *kobj, 645 struct kobj_attribute *a, char *buf) 646 { 647 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); 648 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 649 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf); 650 } 651 BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show); 652 653 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj) 654 #define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj) 655 656 static ssize_t raid_bytes_show(struct kobject *kobj, 657 struct kobj_attribute *attr, char *buf); 658 BTRFS_ATTR(raid, total_bytes, raid_bytes_show); 659 BTRFS_ATTR(raid, used_bytes, raid_bytes_show); 660 661 static ssize_t raid_bytes_show(struct kobject *kobj, 662 struct kobj_attribute *attr, char *buf) 663 664 { 665 struct btrfs_space_info *sinfo = to_space_info(kobj->parent); 666 struct btrfs_block_group *block_group; 667 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags); 668 u64 val = 0; 669 670 down_read(&sinfo->groups_sem); 671 list_for_each_entry(block_group, &sinfo->block_groups[index], list) { 672 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes)) 673 val += block_group->length; 674 else 675 val += block_group->used; 676 } 677 up_read(&sinfo->groups_sem); 678 return sysfs_emit(buf, "%llu\n", val); 679 } 680 681 /* 682 * Allocation information about block group profiles. 683 * 684 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/ 685 */ 686 static struct attribute *raid_attrs[] = { 687 BTRFS_ATTR_PTR(raid, total_bytes), 688 BTRFS_ATTR_PTR(raid, used_bytes), 689 NULL 690 }; 691 ATTRIBUTE_GROUPS(raid); 692 693 static void release_raid_kobj(struct kobject *kobj) 694 { 695 kfree(to_raid_kobj(kobj)); 696 } 697 698 static struct kobj_type btrfs_raid_ktype = { 699 .sysfs_ops = &kobj_sysfs_ops, 700 .release = release_raid_kobj, 701 .default_groups = raid_groups, 702 }; 703 704 #define SPACE_INFO_ATTR(field) \ 705 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \ 706 struct kobj_attribute *a, \ 707 char *buf) \ 708 { \ 709 struct btrfs_space_info *sinfo = to_space_info(kobj); \ 710 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \ 711 } \ 712 BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field) 713 714 SPACE_INFO_ATTR(flags); 715 SPACE_INFO_ATTR(total_bytes); 716 SPACE_INFO_ATTR(bytes_used); 717 SPACE_INFO_ATTR(bytes_pinned); 718 SPACE_INFO_ATTR(bytes_reserved); 719 SPACE_INFO_ATTR(bytes_may_use); 720 SPACE_INFO_ATTR(bytes_readonly); 721 SPACE_INFO_ATTR(bytes_zone_unusable); 722 SPACE_INFO_ATTR(disk_used); 723 SPACE_INFO_ATTR(disk_total); 724 725 /* 726 * Allocation information about block group types. 727 * 728 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/ 729 */ 730 static struct attribute *space_info_attrs[] = { 731 BTRFS_ATTR_PTR(space_info, flags), 732 BTRFS_ATTR_PTR(space_info, total_bytes), 733 BTRFS_ATTR_PTR(space_info, bytes_used), 734 BTRFS_ATTR_PTR(space_info, bytes_pinned), 735 BTRFS_ATTR_PTR(space_info, bytes_reserved), 736 BTRFS_ATTR_PTR(space_info, bytes_may_use), 737 BTRFS_ATTR_PTR(space_info, bytes_readonly), 738 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable), 739 BTRFS_ATTR_PTR(space_info, disk_used), 740 BTRFS_ATTR_PTR(space_info, disk_total), 741 NULL, 742 }; 743 ATTRIBUTE_GROUPS(space_info); 744 745 static void space_info_release(struct kobject *kobj) 746 { 747 struct btrfs_space_info *sinfo = to_space_info(kobj); 748 kfree(sinfo); 749 } 750 751 static struct kobj_type space_info_ktype = { 752 .sysfs_ops = &kobj_sysfs_ops, 753 .release = space_info_release, 754 .default_groups = space_info_groups, 755 }; 756 757 /* 758 * Allocation information about block groups. 759 * 760 * Path: /sys/fs/btrfs/<uuid>/allocation/ 761 */ 762 static const struct attribute *allocation_attrs[] = { 763 BTRFS_ATTR_PTR(allocation, global_rsv_reserved), 764 BTRFS_ATTR_PTR(allocation, global_rsv_size), 765 NULL, 766 }; 767 768 static ssize_t btrfs_label_show(struct kobject *kobj, 769 struct kobj_attribute *a, char *buf) 770 { 771 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 772 char *label = fs_info->super_copy->label; 773 ssize_t ret; 774 775 spin_lock(&fs_info->super_lock); 776 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label); 777 spin_unlock(&fs_info->super_lock); 778 779 return ret; 780 } 781 782 static ssize_t btrfs_label_store(struct kobject *kobj, 783 struct kobj_attribute *a, 784 const char *buf, size_t len) 785 { 786 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 787 size_t p_len; 788 789 if (!fs_info) 790 return -EPERM; 791 792 if (sb_rdonly(fs_info->sb)) 793 return -EROFS; 794 795 /* 796 * p_len is the len until the first occurrence of either 797 * '\n' or '\0' 798 */ 799 p_len = strcspn(buf, "\n"); 800 801 if (p_len >= BTRFS_LABEL_SIZE) 802 return -EINVAL; 803 804 spin_lock(&fs_info->super_lock); 805 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE); 806 memcpy(fs_info->super_copy->label, buf, p_len); 807 spin_unlock(&fs_info->super_lock); 808 809 /* 810 * We don't want to do full transaction commit from inside sysfs 811 */ 812 btrfs_set_pending(fs_info, COMMIT); 813 wake_up_process(fs_info->transaction_kthread); 814 815 return len; 816 } 817 BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store); 818 819 static ssize_t btrfs_nodesize_show(struct kobject *kobj, 820 struct kobj_attribute *a, char *buf) 821 { 822 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 823 824 return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize); 825 } 826 827 BTRFS_ATTR(, nodesize, btrfs_nodesize_show); 828 829 static ssize_t btrfs_sectorsize_show(struct kobject *kobj, 830 struct kobj_attribute *a, char *buf) 831 { 832 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 833 834 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); 835 } 836 837 BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show); 838 839 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj, 840 struct kobj_attribute *a, char *buf) 841 { 842 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 843 844 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); 845 } 846 847 BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show); 848 849 static ssize_t quota_override_show(struct kobject *kobj, 850 struct kobj_attribute *a, char *buf) 851 { 852 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 853 int quota_override; 854 855 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 856 return sysfs_emit(buf, "%d\n", quota_override); 857 } 858 859 static ssize_t quota_override_store(struct kobject *kobj, 860 struct kobj_attribute *a, 861 const char *buf, size_t len) 862 { 863 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 864 unsigned long knob; 865 int err; 866 867 if (!fs_info) 868 return -EPERM; 869 870 if (!capable(CAP_SYS_RESOURCE)) 871 return -EPERM; 872 873 err = kstrtoul(buf, 10, &knob); 874 if (err) 875 return err; 876 if (knob > 1) 877 return -EINVAL; 878 879 if (knob) 880 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 881 else 882 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 883 884 return len; 885 } 886 887 BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store); 888 889 static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj, 890 struct kobj_attribute *a, char *buf) 891 { 892 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 893 894 return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid); 895 } 896 897 BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show); 898 899 static ssize_t btrfs_checksum_show(struct kobject *kobj, 900 struct kobj_attribute *a, char *buf) 901 { 902 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 903 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy); 904 905 return sysfs_emit(buf, "%s (%s)\n", 906 btrfs_super_csum_name(csum_type), 907 crypto_shash_driver_name(fs_info->csum_shash)); 908 } 909 910 BTRFS_ATTR(, checksum, btrfs_checksum_show); 911 912 static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj, 913 struct kobj_attribute *a, char *buf) 914 { 915 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 916 const char *str; 917 918 switch (READ_ONCE(fs_info->exclusive_operation)) { 919 case BTRFS_EXCLOP_NONE: 920 str = "none\n"; 921 break; 922 case BTRFS_EXCLOP_BALANCE: 923 str = "balance\n"; 924 break; 925 case BTRFS_EXCLOP_BALANCE_PAUSED: 926 str = "balance paused\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 sysfs_emit(buf, "%s", str); 948 } 949 BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show); 950 951 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 sysfs_emit(buf, "%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 */ 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" }; 980 981 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 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 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 = sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold)); 1035 1036 return ret; 1037 } 1038 1039 static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj, 1040 struct kobj_attribute *a, 1041 const char *buf, size_t len) 1042 { 1043 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1044 int thresh; 1045 int ret; 1046 1047 ret = kstrtoint(buf, 10, &thresh); 1048 if (ret) 1049 return ret; 1050 1051 if (thresh != 0 && (thresh <= 50 || thresh > 100)) 1052 return -EINVAL; 1053 1054 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh); 1055 1056 return len; 1057 } 1058 BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show, 1059 btrfs_bg_reclaim_threshold_store); 1060 1061 /* 1062 * Per-filesystem information and stats. 1063 * 1064 * Path: /sys/fs/btrfs/<uuid>/ 1065 */ 1066 static const struct attribute *btrfs_attrs[] = { 1067 BTRFS_ATTR_PTR(, label), 1068 BTRFS_ATTR_PTR(, nodesize), 1069 BTRFS_ATTR_PTR(, sectorsize), 1070 BTRFS_ATTR_PTR(, clone_alignment), 1071 BTRFS_ATTR_PTR(, quota_override), 1072 BTRFS_ATTR_PTR(, metadata_uuid), 1073 BTRFS_ATTR_PTR(, checksum), 1074 BTRFS_ATTR_PTR(, exclusive_operation), 1075 BTRFS_ATTR_PTR(, generation), 1076 BTRFS_ATTR_PTR(, read_policy), 1077 BTRFS_ATTR_PTR(, bg_reclaim_threshold), 1078 NULL, 1079 }; 1080 1081 static void btrfs_release_fsid_kobj(struct kobject *kobj) 1082 { 1083 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj); 1084 1085 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject)); 1086 complete(&fs_devs->kobj_unregister); 1087 } 1088 1089 static struct kobj_type btrfs_ktype = { 1090 .sysfs_ops = &kobj_sysfs_ops, 1091 .release = btrfs_release_fsid_kobj, 1092 }; 1093 1094 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj) 1095 { 1096 if (kobj->ktype != &btrfs_ktype) 1097 return NULL; 1098 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj); 1099 } 1100 1101 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj) 1102 { 1103 if (kobj->ktype != &btrfs_ktype) 1104 return NULL; 1105 return to_fs_devs(kobj)->fs_info; 1106 } 1107 1108 #define NUM_FEATURE_BITS 64 1109 #define BTRFS_FEATURE_NAME_MAX 13 1110 static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX]; 1111 static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS]; 1112 1113 static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) == 1114 ARRAY_SIZE(btrfs_feature_attrs)); 1115 static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) == 1116 ARRAY_SIZE(btrfs_feature_attrs[0])); 1117 1118 static const u64 supported_feature_masks[FEAT_MAX] = { 1119 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP, 1120 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP, 1121 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP, 1122 }; 1123 1124 static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add) 1125 { 1126 int set; 1127 1128 for (set = 0; set < FEAT_MAX; set++) { 1129 int i; 1130 struct attribute *attrs[2]; 1131 struct attribute_group agroup = { 1132 .name = "features", 1133 .attrs = attrs, 1134 }; 1135 u64 features = get_features(fs_info, set); 1136 features &= ~supported_feature_masks[set]; 1137 1138 if (!features) 1139 continue; 1140 1141 attrs[1] = NULL; 1142 for (i = 0; i < NUM_FEATURE_BITS; i++) { 1143 struct btrfs_feature_attr *fa; 1144 1145 if (!(features & (1ULL << i))) 1146 continue; 1147 1148 fa = &btrfs_feature_attrs[set][i]; 1149 attrs[0] = &fa->kobj_attr.attr; 1150 if (add) { 1151 int ret; 1152 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj, 1153 &agroup); 1154 if (ret) 1155 return ret; 1156 } else 1157 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj, 1158 &agroup); 1159 } 1160 1161 } 1162 return 0; 1163 } 1164 1165 static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) 1166 { 1167 if (fs_devs->devinfo_kobj) { 1168 kobject_del(fs_devs->devinfo_kobj); 1169 kobject_put(fs_devs->devinfo_kobj); 1170 fs_devs->devinfo_kobj = NULL; 1171 } 1172 1173 if (fs_devs->devices_kobj) { 1174 kobject_del(fs_devs->devices_kobj); 1175 kobject_put(fs_devs->devices_kobj); 1176 fs_devs->devices_kobj = NULL; 1177 } 1178 1179 if (fs_devs->fsid_kobj.state_initialized) { 1180 kobject_del(&fs_devs->fsid_kobj); 1181 kobject_put(&fs_devs->fsid_kobj); 1182 wait_for_completion(&fs_devs->kobj_unregister); 1183 } 1184 } 1185 1186 /* when fs_devs is NULL it will remove all fsid kobject */ 1187 void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) 1188 { 1189 struct list_head *fs_uuids = btrfs_get_fs_uuids(); 1190 1191 if (fs_devs) { 1192 __btrfs_sysfs_remove_fsid(fs_devs); 1193 return; 1194 } 1195 1196 list_for_each_entry(fs_devs, fs_uuids, fs_list) { 1197 __btrfs_sysfs_remove_fsid(fs_devs); 1198 } 1199 } 1200 1201 static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices) 1202 { 1203 struct btrfs_device *device; 1204 struct btrfs_fs_devices *seed; 1205 1206 list_for_each_entry(device, &fs_devices->devices, dev_list) 1207 btrfs_sysfs_remove_device(device); 1208 1209 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { 1210 list_for_each_entry(device, &seed->devices, dev_list) 1211 btrfs_sysfs_remove_device(device); 1212 } 1213 } 1214 1215 void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info) 1216 { 1217 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; 1218 1219 sysfs_remove_link(fsid_kobj, "bdi"); 1220 1221 if (fs_info->space_info_kobj) { 1222 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); 1223 kobject_del(fs_info->space_info_kobj); 1224 kobject_put(fs_info->space_info_kobj); 1225 } 1226 #ifdef CONFIG_BTRFS_DEBUG 1227 if (fs_info->discard_debug_kobj) { 1228 sysfs_remove_files(fs_info->discard_debug_kobj, 1229 discard_debug_attrs); 1230 kobject_del(fs_info->discard_debug_kobj); 1231 kobject_put(fs_info->discard_debug_kobj); 1232 } 1233 if (fs_info->debug_kobj) { 1234 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); 1235 kobject_del(fs_info->debug_kobj); 1236 kobject_put(fs_info->debug_kobj); 1237 } 1238 #endif 1239 addrm_unknown_feature_attrs(fs_info, false); 1240 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group); 1241 sysfs_remove_files(fsid_kobj, btrfs_attrs); 1242 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices); 1243 } 1244 1245 static const char * const btrfs_feature_set_names[FEAT_MAX] = { 1246 [FEAT_COMPAT] = "compat", 1247 [FEAT_COMPAT_RO] = "compat_ro", 1248 [FEAT_INCOMPAT] = "incompat", 1249 }; 1250 1251 const char *btrfs_feature_set_name(enum btrfs_feature_set set) 1252 { 1253 return btrfs_feature_set_names[set]; 1254 } 1255 1256 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags) 1257 { 1258 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */ 1259 int len = 0; 1260 int i; 1261 char *str; 1262 1263 str = kmalloc(bufsize, GFP_KERNEL); 1264 if (!str) 1265 return str; 1266 1267 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 1268 const char *name; 1269 1270 if (!(flags & (1ULL << i))) 1271 continue; 1272 1273 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name; 1274 len += scnprintf(str + len, bufsize - len, "%s%s", 1275 len ? "," : "", name); 1276 } 1277 1278 return str; 1279 } 1280 1281 static void init_feature_attrs(void) 1282 { 1283 struct btrfs_feature_attr *fa; 1284 int set, i; 1285 1286 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs)); 1287 memset(btrfs_unknown_feature_names, 0, 1288 sizeof(btrfs_unknown_feature_names)); 1289 1290 for (i = 0; btrfs_supported_feature_attrs[i]; i++) { 1291 struct btrfs_feature_attr *sfa; 1292 struct attribute *a = btrfs_supported_feature_attrs[i]; 1293 int bit; 1294 sfa = attr_to_btrfs_feature_attr(a); 1295 bit = ilog2(sfa->feature_bit); 1296 fa = &btrfs_feature_attrs[sfa->feature_set][bit]; 1297 1298 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name; 1299 } 1300 1301 for (set = 0; set < FEAT_MAX; set++) { 1302 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 1303 char *name = btrfs_unknown_feature_names[set][i]; 1304 fa = &btrfs_feature_attrs[set][i]; 1305 1306 if (fa->kobj_attr.attr.name) 1307 continue; 1308 1309 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u", 1310 btrfs_feature_set_names[set], i); 1311 1312 fa->kobj_attr.attr.name = name; 1313 fa->kobj_attr.attr.mode = S_IRUGO; 1314 fa->feature_set = set; 1315 fa->feature_bit = 1ULL << i; 1316 } 1317 } 1318 } 1319 1320 /* 1321 * Create a sysfs entry for a given block group type at path 1322 * /sys/fs/btrfs/UUID/allocation/data/TYPE 1323 */ 1324 void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache) 1325 { 1326 struct btrfs_fs_info *fs_info = cache->fs_info; 1327 struct btrfs_space_info *space_info = cache->space_info; 1328 struct raid_kobject *rkobj; 1329 const int index = btrfs_bg_flags_to_raid_index(cache->flags); 1330 unsigned int nofs_flag; 1331 int ret; 1332 1333 /* 1334 * Setup a NOFS context because kobject_add(), deep in its call chain, 1335 * does GFP_KERNEL allocations, and we are often called in a context 1336 * where if reclaim is triggered we can deadlock (we are either holding 1337 * a transaction handle or some lock required for a transaction 1338 * commit). 1339 */ 1340 nofs_flag = memalloc_nofs_save(); 1341 1342 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS); 1343 if (!rkobj) { 1344 memalloc_nofs_restore(nofs_flag); 1345 btrfs_warn(cache->fs_info, 1346 "couldn't alloc memory for raid level kobject"); 1347 return; 1348 } 1349 1350 rkobj->flags = cache->flags; 1351 kobject_init(&rkobj->kobj, &btrfs_raid_ktype); 1352 1353 /* 1354 * We call this either on mount, or if we've created a block group for a 1355 * new index type while running (i.e. when restriping). The running 1356 * case is tricky because we could race with other threads, so we need 1357 * to have this check to make sure we didn't already init the kobject. 1358 * 1359 * We don't have to protect on the free side because it only happens on 1360 * unmount. 1361 */ 1362 spin_lock(&space_info->lock); 1363 if (space_info->block_group_kobjs[index]) { 1364 spin_unlock(&space_info->lock); 1365 kobject_put(&rkobj->kobj); 1366 return; 1367 } else { 1368 space_info->block_group_kobjs[index] = &rkobj->kobj; 1369 } 1370 spin_unlock(&space_info->lock); 1371 1372 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s", 1373 btrfs_bg_type_to_raid_name(rkobj->flags)); 1374 memalloc_nofs_restore(nofs_flag); 1375 if (ret) { 1376 spin_lock(&space_info->lock); 1377 space_info->block_group_kobjs[index] = NULL; 1378 spin_unlock(&space_info->lock); 1379 kobject_put(&rkobj->kobj); 1380 btrfs_warn(fs_info, 1381 "failed to add kobject for block cache, ignoring"); 1382 return; 1383 } 1384 } 1385 1386 /* 1387 * Remove sysfs directories for all block group types of a given space info and 1388 * the space info as well 1389 */ 1390 void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info) 1391 { 1392 int i; 1393 1394 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { 1395 struct kobject *kobj; 1396 1397 kobj = space_info->block_group_kobjs[i]; 1398 space_info->block_group_kobjs[i] = NULL; 1399 if (kobj) { 1400 kobject_del(kobj); 1401 kobject_put(kobj); 1402 } 1403 } 1404 kobject_del(&space_info->kobj); 1405 kobject_put(&space_info->kobj); 1406 } 1407 1408 static const char *alloc_name(u64 flags) 1409 { 1410 switch (flags) { 1411 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA: 1412 return "mixed"; 1413 case BTRFS_BLOCK_GROUP_METADATA: 1414 return "metadata"; 1415 case BTRFS_BLOCK_GROUP_DATA: 1416 return "data"; 1417 case BTRFS_BLOCK_GROUP_SYSTEM: 1418 return "system"; 1419 default: 1420 WARN_ON(1); 1421 return "invalid-combination"; 1422 } 1423 } 1424 1425 /* 1426 * Create a sysfs entry for a space info type at path 1427 * /sys/fs/btrfs/UUID/allocation/TYPE 1428 */ 1429 int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info, 1430 struct btrfs_space_info *space_info) 1431 { 1432 int ret; 1433 1434 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype, 1435 fs_info->space_info_kobj, "%s", 1436 alloc_name(space_info->flags)); 1437 if (ret) { 1438 kobject_put(&space_info->kobj); 1439 return ret; 1440 } 1441 1442 return 0; 1443 } 1444 1445 void btrfs_sysfs_remove_device(struct btrfs_device *device) 1446 { 1447 struct kobject *devices_kobj; 1448 1449 /* 1450 * Seed fs_devices devices_kobj aren't used, fetch kobject from the 1451 * fs_info::fs_devices. 1452 */ 1453 devices_kobj = device->fs_info->fs_devices->devices_kobj; 1454 ASSERT(devices_kobj); 1455 1456 if (device->bdev) 1457 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name); 1458 1459 if (device->devid_kobj.state_initialized) { 1460 kobject_del(&device->devid_kobj); 1461 kobject_put(&device->devid_kobj); 1462 wait_for_completion(&device->kobj_unregister); 1463 } 1464 } 1465 1466 static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj, 1467 struct kobj_attribute *a, 1468 char *buf) 1469 { 1470 int val; 1471 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1472 devid_kobj); 1473 1474 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 1475 1476 return sysfs_emit(buf, "%d\n", val); 1477 } 1478 BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show); 1479 1480 static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj, 1481 struct kobj_attribute *a, char *buf) 1482 { 1483 int val; 1484 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1485 devid_kobj); 1486 1487 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); 1488 1489 return sysfs_emit(buf, "%d\n", val); 1490 } 1491 BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show); 1492 1493 static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj, 1494 struct kobj_attribute *a, 1495 char *buf) 1496 { 1497 int val; 1498 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1499 devid_kobj); 1500 1501 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 1502 1503 return sysfs_emit(buf, "%d\n", val); 1504 } 1505 BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show); 1506 1507 static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj, 1508 struct kobj_attribute *a, 1509 char *buf) 1510 { 1511 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1512 devid_kobj); 1513 1514 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max)); 1515 } 1516 1517 static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj, 1518 struct kobj_attribute *a, 1519 const char *buf, size_t len) 1520 { 1521 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1522 devid_kobj); 1523 char *endptr; 1524 unsigned long long limit; 1525 1526 limit = memparse(buf, &endptr); 1527 WRITE_ONCE(device->scrub_speed_max, limit); 1528 return len; 1529 } 1530 BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show, 1531 btrfs_devinfo_scrub_speed_max_store); 1532 1533 static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj, 1534 struct kobj_attribute *a, char *buf) 1535 { 1536 int val; 1537 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1538 devid_kobj); 1539 1540 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 1541 1542 return sysfs_emit(buf, "%d\n", val); 1543 } 1544 BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show); 1545 1546 static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj, 1547 struct kobj_attribute *a, char *buf) 1548 { 1549 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1550 devid_kobj); 1551 1552 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid); 1553 } 1554 BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show); 1555 1556 static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj, 1557 struct kobj_attribute *a, char *buf) 1558 { 1559 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1560 devid_kobj); 1561 1562 if (!device->dev_stats_valid) 1563 return sysfs_emit(buf, "invalid\n"); 1564 1565 /* 1566 * Print all at once so we get a snapshot of all values from the same 1567 * time. Keep them in sync and in order of definition of 1568 * btrfs_dev_stat_values. 1569 */ 1570 return sysfs_emit(buf, 1571 "write_errs %d\n" 1572 "read_errs %d\n" 1573 "flush_errs %d\n" 1574 "corruption_errs %d\n" 1575 "generation_errs %d\n", 1576 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS), 1577 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS), 1578 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS), 1579 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS), 1580 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS)); 1581 } 1582 BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show); 1583 1584 /* 1585 * Information about one device. 1586 * 1587 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/ 1588 */ 1589 static struct attribute *devid_attrs[] = { 1590 BTRFS_ATTR_PTR(devid, error_stats), 1591 BTRFS_ATTR_PTR(devid, fsid), 1592 BTRFS_ATTR_PTR(devid, in_fs_metadata), 1593 BTRFS_ATTR_PTR(devid, missing), 1594 BTRFS_ATTR_PTR(devid, replace_target), 1595 BTRFS_ATTR_PTR(devid, scrub_speed_max), 1596 BTRFS_ATTR_PTR(devid, writeable), 1597 NULL 1598 }; 1599 ATTRIBUTE_GROUPS(devid); 1600 1601 static void btrfs_release_devid_kobj(struct kobject *kobj) 1602 { 1603 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1604 devid_kobj); 1605 1606 memset(&device->devid_kobj, 0, sizeof(struct kobject)); 1607 complete(&device->kobj_unregister); 1608 } 1609 1610 static struct kobj_type devid_ktype = { 1611 .sysfs_ops = &kobj_sysfs_ops, 1612 .default_groups = devid_groups, 1613 .release = btrfs_release_devid_kobj, 1614 }; 1615 1616 int btrfs_sysfs_add_device(struct btrfs_device *device) 1617 { 1618 int ret; 1619 unsigned int nofs_flag; 1620 struct kobject *devices_kobj; 1621 struct kobject *devinfo_kobj; 1622 1623 /* 1624 * Make sure we use the fs_info::fs_devices to fetch the kobjects even 1625 * for the seed fs_devices 1626 */ 1627 devices_kobj = device->fs_info->fs_devices->devices_kobj; 1628 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj; 1629 ASSERT(devices_kobj); 1630 ASSERT(devinfo_kobj); 1631 1632 nofs_flag = memalloc_nofs_save(); 1633 1634 if (device->bdev) { 1635 struct kobject *disk_kobj = bdev_kobj(device->bdev); 1636 1637 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name); 1638 if (ret) { 1639 btrfs_warn(device->fs_info, 1640 "creating sysfs device link for devid %llu failed: %d", 1641 device->devid, ret); 1642 goto out; 1643 } 1644 } 1645 1646 init_completion(&device->kobj_unregister); 1647 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype, 1648 devinfo_kobj, "%llu", device->devid); 1649 if (ret) { 1650 kobject_put(&device->devid_kobj); 1651 btrfs_warn(device->fs_info, 1652 "devinfo init for devid %llu failed: %d", 1653 device->devid, ret); 1654 } 1655 1656 out: 1657 memalloc_nofs_restore(nofs_flag); 1658 return ret; 1659 } 1660 1661 static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices) 1662 { 1663 int ret; 1664 struct btrfs_device *device; 1665 struct btrfs_fs_devices *seed; 1666 1667 list_for_each_entry(device, &fs_devices->devices, dev_list) { 1668 ret = btrfs_sysfs_add_device(device); 1669 if (ret) 1670 goto fail; 1671 } 1672 1673 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { 1674 list_for_each_entry(device, &seed->devices, dev_list) { 1675 ret = btrfs_sysfs_add_device(device); 1676 if (ret) 1677 goto fail; 1678 } 1679 } 1680 1681 return 0; 1682 1683 fail: 1684 btrfs_sysfs_remove_fs_devices(fs_devices); 1685 return ret; 1686 } 1687 1688 void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action) 1689 { 1690 int ret; 1691 1692 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 1693 if (ret) 1694 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n", 1695 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 1696 &disk_to_dev(bdev->bd_disk)->kobj); 1697 } 1698 1699 void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices) 1700 1701 { 1702 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE]; 1703 1704 /* 1705 * Sprouting changes fsid of the mounted filesystem, rename the fsid 1706 * directory 1707 */ 1708 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid); 1709 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf)) 1710 btrfs_warn(fs_devices->fs_info, 1711 "sysfs: failed to create fsid for sprout"); 1712 } 1713 1714 void btrfs_sysfs_update_devid(struct btrfs_device *device) 1715 { 1716 char tmp[24]; 1717 1718 snprintf(tmp, sizeof(tmp), "%llu", device->devid); 1719 1720 if (kobject_rename(&device->devid_kobj, tmp)) 1721 btrfs_warn(device->fs_devices->fs_info, 1722 "sysfs: failed to update devid for %llu", 1723 device->devid); 1724 } 1725 1726 /* /sys/fs/btrfs/ entry */ 1727 static struct kset *btrfs_kset; 1728 1729 /* 1730 * Creates: 1731 * /sys/fs/btrfs/UUID 1732 * 1733 * Can be called by the device discovery thread. 1734 */ 1735 int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs) 1736 { 1737 int error; 1738 1739 init_completion(&fs_devs->kobj_unregister); 1740 fs_devs->fsid_kobj.kset = btrfs_kset; 1741 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL, 1742 "%pU", fs_devs->fsid); 1743 if (error) { 1744 kobject_put(&fs_devs->fsid_kobj); 1745 return error; 1746 } 1747 1748 fs_devs->devices_kobj = kobject_create_and_add("devices", 1749 &fs_devs->fsid_kobj); 1750 if (!fs_devs->devices_kobj) { 1751 btrfs_err(fs_devs->fs_info, 1752 "failed to init sysfs device interface"); 1753 btrfs_sysfs_remove_fsid(fs_devs); 1754 return -ENOMEM; 1755 } 1756 1757 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo", 1758 &fs_devs->fsid_kobj); 1759 if (!fs_devs->devinfo_kobj) { 1760 btrfs_err(fs_devs->fs_info, 1761 "failed to init sysfs devinfo kobject"); 1762 btrfs_sysfs_remove_fsid(fs_devs); 1763 return -ENOMEM; 1764 } 1765 1766 return 0; 1767 } 1768 1769 int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info) 1770 { 1771 int error; 1772 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices; 1773 struct kobject *fsid_kobj = &fs_devs->fsid_kobj; 1774 1775 error = btrfs_sysfs_add_fs_devices(fs_devs); 1776 if (error) 1777 return error; 1778 1779 error = sysfs_create_files(fsid_kobj, btrfs_attrs); 1780 if (error) { 1781 btrfs_sysfs_remove_fs_devices(fs_devs); 1782 return error; 1783 } 1784 1785 error = sysfs_create_group(fsid_kobj, 1786 &btrfs_feature_attr_group); 1787 if (error) 1788 goto failure; 1789 1790 #ifdef CONFIG_BTRFS_DEBUG 1791 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj); 1792 if (!fs_info->debug_kobj) { 1793 error = -ENOMEM; 1794 goto failure; 1795 } 1796 1797 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); 1798 if (error) 1799 goto failure; 1800 1801 /* Discard directory */ 1802 fs_info->discard_debug_kobj = kobject_create_and_add("discard", 1803 fs_info->debug_kobj); 1804 if (!fs_info->discard_debug_kobj) { 1805 error = -ENOMEM; 1806 goto failure; 1807 } 1808 1809 error = sysfs_create_files(fs_info->discard_debug_kobj, 1810 discard_debug_attrs); 1811 if (error) 1812 goto failure; 1813 #endif 1814 1815 error = addrm_unknown_feature_attrs(fs_info, true); 1816 if (error) 1817 goto failure; 1818 1819 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi"); 1820 if (error) 1821 goto failure; 1822 1823 fs_info->space_info_kobj = kobject_create_and_add("allocation", 1824 fsid_kobj); 1825 if (!fs_info->space_info_kobj) { 1826 error = -ENOMEM; 1827 goto failure; 1828 } 1829 1830 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs); 1831 if (error) 1832 goto failure; 1833 1834 return 0; 1835 failure: 1836 btrfs_sysfs_remove_mounted(fs_info); 1837 return error; 1838 } 1839 1840 static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj) 1841 { 1842 return to_fs_info(kobj->parent->parent); 1843 } 1844 1845 #define QGROUP_ATTR(_member, _show_name) \ 1846 static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \ 1847 struct kobj_attribute *a, \ 1848 char *buf) \ 1849 { \ 1850 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ 1851 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ 1852 struct btrfs_qgroup, kobj); \ 1853 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \ 1854 } \ 1855 BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member) 1856 1857 #define QGROUP_RSV_ATTR(_name, _type) \ 1858 static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \ 1859 struct kobj_attribute *a, \ 1860 char *buf) \ 1861 { \ 1862 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ 1863 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ 1864 struct btrfs_qgroup, kobj); \ 1865 return btrfs_show_u64(&qgroup->rsv.values[_type], \ 1866 &fs_info->qgroup_lock, buf); \ 1867 } \ 1868 BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name) 1869 1870 QGROUP_ATTR(rfer, referenced); 1871 QGROUP_ATTR(excl, exclusive); 1872 QGROUP_ATTR(max_rfer, max_referenced); 1873 QGROUP_ATTR(max_excl, max_exclusive); 1874 QGROUP_ATTR(lim_flags, limit_flags); 1875 QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA); 1876 QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS); 1877 QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC); 1878 1879 /* 1880 * Qgroup information. 1881 * 1882 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/ 1883 */ 1884 static struct attribute *qgroup_attrs[] = { 1885 BTRFS_ATTR_PTR(qgroup, referenced), 1886 BTRFS_ATTR_PTR(qgroup, exclusive), 1887 BTRFS_ATTR_PTR(qgroup, max_referenced), 1888 BTRFS_ATTR_PTR(qgroup, max_exclusive), 1889 BTRFS_ATTR_PTR(qgroup, limit_flags), 1890 BTRFS_ATTR_PTR(qgroup, rsv_data), 1891 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans), 1892 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc), 1893 NULL 1894 }; 1895 ATTRIBUTE_GROUPS(qgroup); 1896 1897 static void qgroup_release(struct kobject *kobj) 1898 { 1899 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj); 1900 1901 memset(&qgroup->kobj, 0, sizeof(*kobj)); 1902 } 1903 1904 static struct kobj_type qgroup_ktype = { 1905 .sysfs_ops = &kobj_sysfs_ops, 1906 .release = qgroup_release, 1907 .default_groups = qgroup_groups, 1908 }; 1909 1910 int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info, 1911 struct btrfs_qgroup *qgroup) 1912 { 1913 struct kobject *qgroups_kobj = fs_info->qgroups_kobj; 1914 int ret; 1915 1916 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 1917 return 0; 1918 if (qgroup->kobj.state_initialized) 1919 return 0; 1920 if (!qgroups_kobj) 1921 return -EINVAL; 1922 1923 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj, 1924 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid), 1925 btrfs_qgroup_subvolid(qgroup->qgroupid)); 1926 if (ret < 0) 1927 kobject_put(&qgroup->kobj); 1928 1929 return ret; 1930 } 1931 1932 void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info) 1933 { 1934 struct btrfs_qgroup *qgroup; 1935 struct btrfs_qgroup *next; 1936 1937 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 1938 return; 1939 1940 rbtree_postorder_for_each_entry_safe(qgroup, next, 1941 &fs_info->qgroup_tree, node) 1942 btrfs_sysfs_del_one_qgroup(fs_info, qgroup); 1943 if (fs_info->qgroups_kobj) { 1944 kobject_del(fs_info->qgroups_kobj); 1945 kobject_put(fs_info->qgroups_kobj); 1946 fs_info->qgroups_kobj = NULL; 1947 } 1948 } 1949 1950 /* Called when qgroups get initialized, thus there is no need for locking */ 1951 int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info) 1952 { 1953 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; 1954 struct btrfs_qgroup *qgroup; 1955 struct btrfs_qgroup *next; 1956 int ret = 0; 1957 1958 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 1959 return 0; 1960 1961 ASSERT(fsid_kobj); 1962 if (fs_info->qgroups_kobj) 1963 return 0; 1964 1965 fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj); 1966 if (!fs_info->qgroups_kobj) { 1967 ret = -ENOMEM; 1968 goto out; 1969 } 1970 rbtree_postorder_for_each_entry_safe(qgroup, next, 1971 &fs_info->qgroup_tree, node) { 1972 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); 1973 if (ret < 0) 1974 goto out; 1975 } 1976 1977 out: 1978 if (ret < 0) 1979 btrfs_sysfs_del_qgroups(fs_info); 1980 return ret; 1981 } 1982 1983 void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info, 1984 struct btrfs_qgroup *qgroup) 1985 { 1986 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 1987 return; 1988 1989 if (qgroup->kobj.state_initialized) { 1990 kobject_del(&qgroup->kobj); 1991 kobject_put(&qgroup->kobj); 1992 } 1993 } 1994 1995 /* 1996 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current 1997 * values in superblock. Call after any changes to incompat/compat_ro flags 1998 */ 1999 void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info, 2000 u64 bit, enum btrfs_feature_set set) 2001 { 2002 struct btrfs_fs_devices *fs_devs; 2003 struct kobject *fsid_kobj; 2004 u64 __maybe_unused features; 2005 int __maybe_unused ret; 2006 2007 if (!fs_info) 2008 return; 2009 2010 /* 2011 * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not 2012 * safe when called from some contexts (eg. balance) 2013 */ 2014 features = get_features(fs_info, set); 2015 ASSERT(bit & supported_feature_masks[set]); 2016 2017 fs_devs = fs_info->fs_devices; 2018 fsid_kobj = &fs_devs->fsid_kobj; 2019 2020 if (!fsid_kobj->state_initialized) 2021 return; 2022 2023 /* 2024 * FIXME: this is too heavy to update just one value, ideally we'd like 2025 * to use sysfs_update_group but some refactoring is needed first. 2026 */ 2027 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group); 2028 ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group); 2029 } 2030 2031 int __init btrfs_init_sysfs(void) 2032 { 2033 int ret; 2034 2035 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); 2036 if (!btrfs_kset) 2037 return -ENOMEM; 2038 2039 init_feature_attrs(); 2040 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2041 if (ret) 2042 goto out2; 2043 ret = sysfs_merge_group(&btrfs_kset->kobj, 2044 &btrfs_static_feature_attr_group); 2045 if (ret) 2046 goto out_remove_group; 2047 2048 #ifdef CONFIG_BTRFS_DEBUG 2049 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); 2050 if (ret) 2051 goto out2; 2052 #endif 2053 2054 return 0; 2055 2056 out_remove_group: 2057 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2058 out2: 2059 kset_unregister(btrfs_kset); 2060 2061 return ret; 2062 } 2063 2064 void __cold btrfs_exit_sysfs(void) 2065 { 2066 sysfs_unmerge_group(&btrfs_kset->kobj, 2067 &btrfs_static_feature_attr_group); 2068 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2069 #ifdef CONFIG_BTRFS_DEBUG 2070 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); 2071 #endif 2072 kset_unregister(btrfs_kset); 2073 } 2074 2075