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 #include "messages.h" 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 #include "misc.h" 25 #include "fs.h" 26 #include "accessors.h" 27 28 /* 29 * Structure name Path 30 * -------------------------------------------------------------------------- 31 * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features 32 * btrfs_supported_feature_attrs /sys/fs/btrfs/features and 33 * /sys/fs/btrfs/<uuid>/features 34 * btrfs_attrs /sys/fs/btrfs/<uuid> 35 * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid> 36 * allocation_attrs /sys/fs/btrfs/<uuid>/allocation 37 * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid> 38 * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type> 39 * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile> 40 * discard_attrs /sys/fs/btrfs/<uuid>/discard 41 * 42 * When built with BTRFS_CONFIG_DEBUG: 43 * 44 * btrfs_debug_feature_attrs /sys/fs/btrfs/debug 45 * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug 46 */ 47 48 struct btrfs_feature_attr { 49 struct kobj_attribute kobj_attr; 50 enum btrfs_feature_set feature_set; 51 u64 feature_bit; 52 }; 53 54 /* For raid type sysfs entries */ 55 struct raid_kobject { 56 u64 flags; 57 struct kobject kobj; 58 }; 59 60 #define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \ 61 { \ 62 .attr = { .name = __stringify(_name), .mode = _mode }, \ 63 .show = _show, \ 64 .store = _store, \ 65 } 66 67 #define BTRFS_ATTR_W(_prefix, _name, _store) \ 68 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ 69 __INIT_KOBJ_ATTR(_name, 0200, NULL, _store) 70 71 #define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \ 72 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ 73 __INIT_KOBJ_ATTR(_name, 0644, _show, _store) 74 75 #define BTRFS_ATTR(_prefix, _name, _show) \ 76 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ 77 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL) 78 79 #define BTRFS_ATTR_PTR(_prefix, _name) \ 80 (&btrfs_attr_##_prefix##_##_name.attr) 81 82 #define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \ 83 static struct btrfs_feature_attr btrfs_attr_features_##_name = { \ 84 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \ 85 btrfs_feature_attr_show, \ 86 btrfs_feature_attr_store), \ 87 .feature_set = _feature_set, \ 88 .feature_bit = _feature_prefix ##_## _feature_bit, \ 89 } 90 #define BTRFS_FEAT_ATTR_PTR(_name) \ 91 (&btrfs_attr_features_##_name.kobj_attr.attr) 92 93 #define BTRFS_FEAT_ATTR_COMPAT(name, feature) \ 94 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature) 95 #define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \ 96 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature) 97 #define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \ 98 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature) 99 100 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj); 101 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj); 102 static struct kobject *get_btrfs_kobj(struct kobject *kobj); 103 104 static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a) 105 { 106 return container_of(a, struct btrfs_feature_attr, kobj_attr); 107 } 108 109 static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr) 110 { 111 return container_of(attr, struct kobj_attribute, attr); 112 } 113 114 static struct btrfs_feature_attr *attr_to_btrfs_feature_attr( 115 struct attribute *attr) 116 { 117 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr)); 118 } 119 120 static u64 get_features(struct btrfs_fs_info *fs_info, 121 enum btrfs_feature_set set) 122 { 123 struct btrfs_super_block *disk_super = fs_info->super_copy; 124 if (set == FEAT_COMPAT) 125 return btrfs_super_compat_flags(disk_super); 126 else if (set == FEAT_COMPAT_RO) 127 return btrfs_super_compat_ro_flags(disk_super); 128 else 129 return btrfs_super_incompat_flags(disk_super); 130 } 131 132 static void set_features(struct btrfs_fs_info *fs_info, 133 enum btrfs_feature_set set, u64 features) 134 { 135 struct btrfs_super_block *disk_super = fs_info->super_copy; 136 if (set == FEAT_COMPAT) 137 btrfs_set_super_compat_flags(disk_super, features); 138 else if (set == FEAT_COMPAT_RO) 139 btrfs_set_super_compat_ro_flags(disk_super, features); 140 else 141 btrfs_set_super_incompat_flags(disk_super, features); 142 } 143 144 static int can_modify_feature(struct btrfs_feature_attr *fa) 145 { 146 int val = 0; 147 u64 set, clear; 148 switch (fa->feature_set) { 149 case FEAT_COMPAT: 150 set = BTRFS_FEATURE_COMPAT_SAFE_SET; 151 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR; 152 break; 153 case FEAT_COMPAT_RO: 154 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET; 155 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR; 156 break; 157 case FEAT_INCOMPAT: 158 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET; 159 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR; 160 break; 161 default: 162 pr_warn("btrfs: sysfs: unknown feature set %d\n", 163 fa->feature_set); 164 return 0; 165 } 166 167 if (set & fa->feature_bit) 168 val |= 1; 169 if (clear & fa->feature_bit) 170 val |= 2; 171 172 return val; 173 } 174 175 static ssize_t btrfs_feature_attr_show(struct kobject *kobj, 176 struct kobj_attribute *a, char *buf) 177 { 178 int val = 0; 179 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 180 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a); 181 if (fs_info) { 182 u64 features = get_features(fs_info, fa->feature_set); 183 if (features & fa->feature_bit) 184 val = 1; 185 } else 186 val = can_modify_feature(fa); 187 188 return sysfs_emit(buf, "%d\n", val); 189 } 190 191 static ssize_t btrfs_feature_attr_store(struct kobject *kobj, 192 struct kobj_attribute *a, 193 const char *buf, size_t count) 194 { 195 struct btrfs_fs_info *fs_info; 196 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a); 197 u64 features, set, clear; 198 unsigned long val; 199 int ret; 200 201 fs_info = to_fs_info(kobj); 202 if (!fs_info) 203 return -EPERM; 204 205 if (sb_rdonly(fs_info->sb)) 206 return -EROFS; 207 208 ret = kstrtoul(skip_spaces(buf), 0, &val); 209 if (ret) 210 return ret; 211 212 if (fa->feature_set == FEAT_COMPAT) { 213 set = BTRFS_FEATURE_COMPAT_SAFE_SET; 214 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR; 215 } else if (fa->feature_set == FEAT_COMPAT_RO) { 216 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET; 217 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR; 218 } else { 219 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET; 220 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR; 221 } 222 223 features = get_features(fs_info, fa->feature_set); 224 225 /* Nothing to do */ 226 if ((val && (features & fa->feature_bit)) || 227 (!val && !(features & fa->feature_bit))) 228 return count; 229 230 if ((val && !(set & fa->feature_bit)) || 231 (!val && !(clear & fa->feature_bit))) { 232 btrfs_info(fs_info, 233 "%sabling feature %s on mounted fs is not supported.", 234 val ? "En" : "Dis", fa->kobj_attr.attr.name); 235 return -EPERM; 236 } 237 238 btrfs_info(fs_info, "%s %s feature flag", 239 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name); 240 241 spin_lock(&fs_info->super_lock); 242 features = get_features(fs_info, fa->feature_set); 243 if (val) 244 features |= fa->feature_bit; 245 else 246 features &= ~fa->feature_bit; 247 set_features(fs_info, fa->feature_set, features); 248 spin_unlock(&fs_info->super_lock); 249 250 /* 251 * We don't want to do full transaction commit from inside sysfs 252 */ 253 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags); 254 wake_up_process(fs_info->transaction_kthread); 255 256 return count; 257 } 258 259 static umode_t btrfs_feature_visible(struct kobject *kobj, 260 struct attribute *attr, int unused) 261 { 262 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 263 umode_t mode = attr->mode; 264 265 if (fs_info) { 266 struct btrfs_feature_attr *fa; 267 u64 features; 268 269 fa = attr_to_btrfs_feature_attr(attr); 270 features = get_features(fs_info, fa->feature_set); 271 272 if (can_modify_feature(fa)) 273 mode |= S_IWUSR; 274 else if (!(features & fa->feature_bit)) 275 mode = 0; 276 } 277 278 return mode; 279 } 280 281 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL); 282 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS); 283 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO); 284 BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD); 285 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF); 286 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56); 287 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA); 288 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES); 289 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID); 290 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE); 291 BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE); 292 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34); 293 #ifdef CONFIG_BLK_DEV_ZONED 294 BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED); 295 #endif 296 #ifdef CONFIG_BTRFS_DEBUG 297 /* Remove once support for extent tree v2 is feature complete */ 298 BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2); 299 #endif 300 #ifdef CONFIG_FS_VERITY 301 BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY); 302 #endif 303 304 /* 305 * Features which depend on feature bits and may differ between each fs. 306 * 307 * /sys/fs/btrfs/features - all available features implemented by this version 308 * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or 309 * can be changed on a mounted filesystem. 310 */ 311 static struct attribute *btrfs_supported_feature_attrs[] = { 312 BTRFS_FEAT_ATTR_PTR(default_subvol), 313 BTRFS_FEAT_ATTR_PTR(mixed_groups), 314 BTRFS_FEAT_ATTR_PTR(compress_lzo), 315 BTRFS_FEAT_ATTR_PTR(compress_zstd), 316 BTRFS_FEAT_ATTR_PTR(extended_iref), 317 BTRFS_FEAT_ATTR_PTR(raid56), 318 BTRFS_FEAT_ATTR_PTR(skinny_metadata), 319 BTRFS_FEAT_ATTR_PTR(no_holes), 320 BTRFS_FEAT_ATTR_PTR(metadata_uuid), 321 BTRFS_FEAT_ATTR_PTR(free_space_tree), 322 BTRFS_FEAT_ATTR_PTR(raid1c34), 323 BTRFS_FEAT_ATTR_PTR(block_group_tree), 324 #ifdef CONFIG_BLK_DEV_ZONED 325 BTRFS_FEAT_ATTR_PTR(zoned), 326 #endif 327 #ifdef CONFIG_BTRFS_DEBUG 328 BTRFS_FEAT_ATTR_PTR(extent_tree_v2), 329 #endif 330 #ifdef CONFIG_FS_VERITY 331 BTRFS_FEAT_ATTR_PTR(verity), 332 #endif 333 NULL 334 }; 335 336 static const struct attribute_group btrfs_feature_attr_group = { 337 .name = "features", 338 .is_visible = btrfs_feature_visible, 339 .attrs = btrfs_supported_feature_attrs, 340 }; 341 342 static ssize_t rmdir_subvol_show(struct kobject *kobj, 343 struct kobj_attribute *ka, char *buf) 344 { 345 return sysfs_emit(buf, "0\n"); 346 } 347 BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show); 348 349 static ssize_t supported_checksums_show(struct kobject *kobj, 350 struct kobj_attribute *a, char *buf) 351 { 352 ssize_t ret = 0; 353 int i; 354 355 for (i = 0; i < btrfs_get_num_csums(); i++) { 356 /* 357 * This "trick" only works as long as 'enum btrfs_csum_type' has 358 * no holes in it 359 */ 360 ret += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "), 361 btrfs_super_csum_name(i)); 362 363 } 364 365 ret += sysfs_emit_at(buf, ret, "\n"); 366 return ret; 367 } 368 BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show); 369 370 static ssize_t send_stream_version_show(struct kobject *kobj, 371 struct kobj_attribute *ka, char *buf) 372 { 373 return sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION); 374 } 375 BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show); 376 377 static const char *rescue_opts[] = { 378 "usebackuproot", 379 "nologreplay", 380 "ignorebadroots", 381 "ignoredatacsums", 382 "all", 383 }; 384 385 static ssize_t supported_rescue_options_show(struct kobject *kobj, 386 struct kobj_attribute *a, 387 char *buf) 388 { 389 ssize_t ret = 0; 390 int i; 391 392 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++) 393 ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]); 394 ret += sysfs_emit_at(buf, ret, "\n"); 395 return ret; 396 } 397 BTRFS_ATTR(static_feature, supported_rescue_options, 398 supported_rescue_options_show); 399 400 static ssize_t supported_sectorsizes_show(struct kobject *kobj, 401 struct kobj_attribute *a, 402 char *buf) 403 { 404 ssize_t ret = 0; 405 406 /* An artificial limit to only support 4K and PAGE_SIZE */ 407 if (PAGE_SIZE > SZ_4K) 408 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K); 409 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE); 410 411 return ret; 412 } 413 BTRFS_ATTR(static_feature, supported_sectorsizes, 414 supported_sectorsizes_show); 415 416 /* 417 * Features which only depend on kernel version. 418 * 419 * These are listed in /sys/fs/btrfs/features along with 420 * btrfs_supported_feature_attrs. 421 */ 422 static struct attribute *btrfs_supported_static_feature_attrs[] = { 423 BTRFS_ATTR_PTR(static_feature, rmdir_subvol), 424 BTRFS_ATTR_PTR(static_feature, supported_checksums), 425 BTRFS_ATTR_PTR(static_feature, send_stream_version), 426 BTRFS_ATTR_PTR(static_feature, supported_rescue_options), 427 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes), 428 NULL 429 }; 430 431 static const struct attribute_group btrfs_static_feature_attr_group = { 432 .name = "features", 433 .attrs = btrfs_supported_static_feature_attrs, 434 }; 435 436 /* 437 * Discard statistics and tunables 438 */ 439 #define discard_to_fs_info(_kobj) to_fs_info(get_btrfs_kobj(_kobj)) 440 441 static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj, 442 struct kobj_attribute *a, 443 char *buf) 444 { 445 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 446 447 return sysfs_emit(buf, "%lld\n", 448 atomic64_read(&fs_info->discard_ctl.discardable_bytes)); 449 } 450 BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show); 451 452 static ssize_t btrfs_discardable_extents_show(struct kobject *kobj, 453 struct kobj_attribute *a, 454 char *buf) 455 { 456 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 457 458 return sysfs_emit(buf, "%d\n", 459 atomic_read(&fs_info->discard_ctl.discardable_extents)); 460 } 461 BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show); 462 463 static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj, 464 struct kobj_attribute *a, 465 char *buf) 466 { 467 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 468 469 return sysfs_emit(buf, "%llu\n", 470 fs_info->discard_ctl.discard_bitmap_bytes); 471 } 472 BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show); 473 474 static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj, 475 struct kobj_attribute *a, 476 char *buf) 477 { 478 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 479 480 return sysfs_emit(buf, "%lld\n", 481 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved)); 482 } 483 BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show); 484 485 static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj, 486 struct kobj_attribute *a, 487 char *buf) 488 { 489 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 490 491 return sysfs_emit(buf, "%llu\n", 492 fs_info->discard_ctl.discard_extent_bytes); 493 } 494 BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show); 495 496 static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj, 497 struct kobj_attribute *a, 498 char *buf) 499 { 500 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 501 502 return sysfs_emit(buf, "%u\n", 503 READ_ONCE(fs_info->discard_ctl.iops_limit)); 504 } 505 506 static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj, 507 struct kobj_attribute *a, 508 const char *buf, size_t len) 509 { 510 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 511 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 512 u32 iops_limit; 513 int ret; 514 515 ret = kstrtou32(buf, 10, &iops_limit); 516 if (ret) 517 return -EINVAL; 518 519 WRITE_ONCE(discard_ctl->iops_limit, iops_limit); 520 btrfs_discard_calc_delay(discard_ctl); 521 btrfs_discard_schedule_work(discard_ctl, true); 522 return len; 523 } 524 BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show, 525 btrfs_discard_iops_limit_store); 526 527 static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj, 528 struct kobj_attribute *a, 529 char *buf) 530 { 531 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 532 533 return sysfs_emit(buf, "%u\n", 534 READ_ONCE(fs_info->discard_ctl.kbps_limit)); 535 } 536 537 static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj, 538 struct kobj_attribute *a, 539 const char *buf, size_t len) 540 { 541 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 542 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 543 u32 kbps_limit; 544 int ret; 545 546 ret = kstrtou32(buf, 10, &kbps_limit); 547 if (ret) 548 return -EINVAL; 549 550 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit); 551 btrfs_discard_schedule_work(discard_ctl, true); 552 return len; 553 } 554 BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show, 555 btrfs_discard_kbps_limit_store); 556 557 static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj, 558 struct kobj_attribute *a, 559 char *buf) 560 { 561 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 562 563 return sysfs_emit(buf, "%llu\n", 564 READ_ONCE(fs_info->discard_ctl.max_discard_size)); 565 } 566 567 static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj, 568 struct kobj_attribute *a, 569 const char *buf, size_t len) 570 { 571 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 572 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 573 u64 max_discard_size; 574 int ret; 575 576 ret = kstrtou64(buf, 10, &max_discard_size); 577 if (ret) 578 return -EINVAL; 579 580 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size); 581 582 return len; 583 } 584 BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show, 585 btrfs_discard_max_discard_size_store); 586 587 /* 588 * Per-filesystem stats for discard (when mounted with discard=async). 589 * 590 * Path: /sys/fs/btrfs/<uuid>/discard/ 591 */ 592 static const struct attribute *discard_attrs[] = { 593 BTRFS_ATTR_PTR(discard, discardable_bytes), 594 BTRFS_ATTR_PTR(discard, discardable_extents), 595 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes), 596 BTRFS_ATTR_PTR(discard, discard_bytes_saved), 597 BTRFS_ATTR_PTR(discard, discard_extent_bytes), 598 BTRFS_ATTR_PTR(discard, iops_limit), 599 BTRFS_ATTR_PTR(discard, kbps_limit), 600 BTRFS_ATTR_PTR(discard, max_discard_size), 601 NULL, 602 }; 603 604 #ifdef CONFIG_BTRFS_DEBUG 605 606 /* 607 * Per-filesystem runtime debugging exported via sysfs. 608 * 609 * Path: /sys/fs/btrfs/UUID/debug/ 610 */ 611 static const struct attribute *btrfs_debug_mount_attrs[] = { 612 NULL, 613 }; 614 615 /* 616 * Runtime debugging exported via sysfs, applies to all mounted filesystems. 617 * 618 * Path: /sys/fs/btrfs/debug 619 */ 620 static struct attribute *btrfs_debug_feature_attrs[] = { 621 NULL 622 }; 623 624 static const struct attribute_group btrfs_debug_feature_attr_group = { 625 .name = "debug", 626 .attrs = btrfs_debug_feature_attrs, 627 }; 628 629 #endif 630 631 static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf) 632 { 633 u64 val; 634 if (lock) 635 spin_lock(lock); 636 val = *value_ptr; 637 if (lock) 638 spin_unlock(lock); 639 return sysfs_emit(buf, "%llu\n", val); 640 } 641 642 static ssize_t global_rsv_size_show(struct kobject *kobj, 643 struct kobj_attribute *ka, char *buf) 644 { 645 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); 646 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 647 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf); 648 } 649 BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show); 650 651 static ssize_t global_rsv_reserved_show(struct kobject *kobj, 652 struct kobj_attribute *a, char *buf) 653 { 654 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); 655 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 656 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf); 657 } 658 BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show); 659 660 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj) 661 #define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj) 662 663 static ssize_t raid_bytes_show(struct kobject *kobj, 664 struct kobj_attribute *attr, char *buf); 665 BTRFS_ATTR(raid, total_bytes, raid_bytes_show); 666 BTRFS_ATTR(raid, used_bytes, raid_bytes_show); 667 668 static ssize_t raid_bytes_show(struct kobject *kobj, 669 struct kobj_attribute *attr, char *buf) 670 671 { 672 struct btrfs_space_info *sinfo = to_space_info(kobj->parent); 673 struct btrfs_block_group *block_group; 674 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags); 675 u64 val = 0; 676 677 down_read(&sinfo->groups_sem); 678 list_for_each_entry(block_group, &sinfo->block_groups[index], list) { 679 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes)) 680 val += block_group->length; 681 else 682 val += block_group->used; 683 } 684 up_read(&sinfo->groups_sem); 685 return sysfs_emit(buf, "%llu\n", val); 686 } 687 688 /* 689 * Allocation information about block group profiles. 690 * 691 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/ 692 */ 693 static struct attribute *raid_attrs[] = { 694 BTRFS_ATTR_PTR(raid, total_bytes), 695 BTRFS_ATTR_PTR(raid, used_bytes), 696 NULL 697 }; 698 ATTRIBUTE_GROUPS(raid); 699 700 static void release_raid_kobj(struct kobject *kobj) 701 { 702 kfree(to_raid_kobj(kobj)); 703 } 704 705 static const struct kobj_type btrfs_raid_ktype = { 706 .sysfs_ops = &kobj_sysfs_ops, 707 .release = release_raid_kobj, 708 .default_groups = raid_groups, 709 }; 710 711 #define SPACE_INFO_ATTR(field) \ 712 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \ 713 struct kobj_attribute *a, \ 714 char *buf) \ 715 { \ 716 struct btrfs_space_info *sinfo = to_space_info(kobj); \ 717 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \ 718 } \ 719 BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field) 720 721 static ssize_t btrfs_chunk_size_show(struct kobject *kobj, 722 struct kobj_attribute *a, char *buf) 723 { 724 struct btrfs_space_info *sinfo = to_space_info(kobj); 725 726 return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size)); 727 } 728 729 /* 730 * Store new chunk size in space info. Can be called on a read-only filesystem. 731 * 732 * If the new chunk size value is larger than 10% of free space it is reduced 733 * to match that limit. Alignment must be to 256M and the system chunk size 734 * cannot be set. 735 */ 736 static ssize_t btrfs_chunk_size_store(struct kobject *kobj, 737 struct kobj_attribute *a, 738 const char *buf, size_t len) 739 { 740 struct btrfs_space_info *space_info = to_space_info(kobj); 741 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj)); 742 char *retptr; 743 u64 val; 744 745 if (!capable(CAP_SYS_ADMIN)) 746 return -EPERM; 747 748 if (!fs_info->fs_devices) 749 return -EINVAL; 750 751 if (btrfs_is_zoned(fs_info)) 752 return -EINVAL; 753 754 /* System block type must not be changed. */ 755 if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM) 756 return -EPERM; 757 758 val = memparse(buf, &retptr); 759 /* There could be trailing '\n', also catch any typos after the value */ 760 retptr = skip_spaces(retptr); 761 if (*retptr != 0 || val == 0) 762 return -EINVAL; 763 764 val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE); 765 766 /* Limit stripe size to 10% of available space. */ 767 val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val); 768 769 /* Must be multiple of 256M. */ 770 val &= ~((u64)SZ_256M - 1); 771 772 /* Must be at least 256M. */ 773 if (val < SZ_256M) 774 return -EINVAL; 775 776 btrfs_update_space_info_chunk_size(space_info, val); 777 778 return len; 779 } 780 781 #ifdef CONFIG_BTRFS_DEBUG 782 /* 783 * Request chunk allocation with current chunk size. 784 */ 785 static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj, 786 struct kobj_attribute *a, 787 const char *buf, size_t len) 788 { 789 struct btrfs_space_info *space_info = to_space_info(kobj); 790 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj)); 791 struct btrfs_trans_handle *trans; 792 bool val; 793 int ret; 794 795 if (!capable(CAP_SYS_ADMIN)) 796 return -EPERM; 797 798 if (sb_rdonly(fs_info->sb)) 799 return -EROFS; 800 801 ret = kstrtobool(buf, &val); 802 if (ret) 803 return ret; 804 805 if (!val) 806 return -EINVAL; 807 808 /* 809 * This is unsafe to be called from sysfs context and may cause 810 * unexpected problems. 811 */ 812 trans = btrfs_start_transaction(fs_info->tree_root, 0); 813 if (IS_ERR(trans)) 814 return PTR_ERR(trans); 815 ret = btrfs_force_chunk_alloc(trans, space_info->flags); 816 btrfs_end_transaction(trans); 817 818 if (ret == 1) 819 return len; 820 821 return -ENOSPC; 822 } 823 BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store); 824 825 #endif 826 827 SPACE_INFO_ATTR(flags); 828 SPACE_INFO_ATTR(total_bytes); 829 SPACE_INFO_ATTR(bytes_used); 830 SPACE_INFO_ATTR(bytes_pinned); 831 SPACE_INFO_ATTR(bytes_reserved); 832 SPACE_INFO_ATTR(bytes_may_use); 833 SPACE_INFO_ATTR(bytes_readonly); 834 SPACE_INFO_ATTR(bytes_zone_unusable); 835 SPACE_INFO_ATTR(disk_used); 836 SPACE_INFO_ATTR(disk_total); 837 BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store); 838 839 static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj, 840 struct kobj_attribute *a, 841 char *buf) 842 { 843 struct btrfs_space_info *space_info = to_space_info(kobj); 844 845 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->bg_reclaim_threshold)); 846 } 847 848 static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj, 849 struct kobj_attribute *a, 850 const char *buf, size_t len) 851 { 852 struct btrfs_space_info *space_info = to_space_info(kobj); 853 int thresh; 854 int ret; 855 856 ret = kstrtoint(buf, 10, &thresh); 857 if (ret) 858 return ret; 859 860 if (thresh < 0 || thresh > 100) 861 return -EINVAL; 862 863 WRITE_ONCE(space_info->bg_reclaim_threshold, thresh); 864 865 return len; 866 } 867 868 BTRFS_ATTR_RW(space_info, bg_reclaim_threshold, 869 btrfs_sinfo_bg_reclaim_threshold_show, 870 btrfs_sinfo_bg_reclaim_threshold_store); 871 872 /* 873 * Allocation information about block group types. 874 * 875 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/ 876 */ 877 static struct attribute *space_info_attrs[] = { 878 BTRFS_ATTR_PTR(space_info, flags), 879 BTRFS_ATTR_PTR(space_info, total_bytes), 880 BTRFS_ATTR_PTR(space_info, bytes_used), 881 BTRFS_ATTR_PTR(space_info, bytes_pinned), 882 BTRFS_ATTR_PTR(space_info, bytes_reserved), 883 BTRFS_ATTR_PTR(space_info, bytes_may_use), 884 BTRFS_ATTR_PTR(space_info, bytes_readonly), 885 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable), 886 BTRFS_ATTR_PTR(space_info, disk_used), 887 BTRFS_ATTR_PTR(space_info, disk_total), 888 BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold), 889 BTRFS_ATTR_PTR(space_info, chunk_size), 890 #ifdef CONFIG_BTRFS_DEBUG 891 BTRFS_ATTR_PTR(space_info, force_chunk_alloc), 892 #endif 893 NULL, 894 }; 895 ATTRIBUTE_GROUPS(space_info); 896 897 static void space_info_release(struct kobject *kobj) 898 { 899 struct btrfs_space_info *sinfo = to_space_info(kobj); 900 kfree(sinfo); 901 } 902 903 static const struct kobj_type space_info_ktype = { 904 .sysfs_ops = &kobj_sysfs_ops, 905 .release = space_info_release, 906 .default_groups = space_info_groups, 907 }; 908 909 /* 910 * Allocation information about block groups. 911 * 912 * Path: /sys/fs/btrfs/<uuid>/allocation/ 913 */ 914 static const struct attribute *allocation_attrs[] = { 915 BTRFS_ATTR_PTR(allocation, global_rsv_reserved), 916 BTRFS_ATTR_PTR(allocation, global_rsv_size), 917 NULL, 918 }; 919 920 static ssize_t btrfs_label_show(struct kobject *kobj, 921 struct kobj_attribute *a, char *buf) 922 { 923 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 924 char *label = fs_info->super_copy->label; 925 ssize_t ret; 926 927 spin_lock(&fs_info->super_lock); 928 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label); 929 spin_unlock(&fs_info->super_lock); 930 931 return ret; 932 } 933 934 static ssize_t btrfs_label_store(struct kobject *kobj, 935 struct kobj_attribute *a, 936 const char *buf, size_t len) 937 { 938 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 939 size_t p_len; 940 941 if (!fs_info) 942 return -EPERM; 943 944 if (sb_rdonly(fs_info->sb)) 945 return -EROFS; 946 947 /* 948 * p_len is the len until the first occurrence of either 949 * '\n' or '\0' 950 */ 951 p_len = strcspn(buf, "\n"); 952 953 if (p_len >= BTRFS_LABEL_SIZE) 954 return -EINVAL; 955 956 spin_lock(&fs_info->super_lock); 957 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE); 958 memcpy(fs_info->super_copy->label, buf, p_len); 959 spin_unlock(&fs_info->super_lock); 960 961 /* 962 * We don't want to do full transaction commit from inside sysfs 963 */ 964 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags); 965 wake_up_process(fs_info->transaction_kthread); 966 967 return len; 968 } 969 BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store); 970 971 static ssize_t btrfs_nodesize_show(struct kobject *kobj, 972 struct kobj_attribute *a, char *buf) 973 { 974 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 975 976 return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize); 977 } 978 979 BTRFS_ATTR(, nodesize, btrfs_nodesize_show); 980 981 static ssize_t btrfs_sectorsize_show(struct kobject *kobj, 982 struct kobj_attribute *a, char *buf) 983 { 984 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 985 986 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); 987 } 988 989 BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show); 990 991 static ssize_t btrfs_commit_stats_show(struct kobject *kobj, 992 struct kobj_attribute *a, char *buf) 993 { 994 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 995 996 return sysfs_emit(buf, 997 "commits %llu\n" 998 "last_commit_ms %llu\n" 999 "max_commit_ms %llu\n" 1000 "total_commit_ms %llu\n", 1001 fs_info->commit_stats.commit_count, 1002 div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC), 1003 div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC), 1004 div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC)); 1005 } 1006 1007 static ssize_t btrfs_commit_stats_store(struct kobject *kobj, 1008 struct kobj_attribute *a, 1009 const char *buf, size_t len) 1010 { 1011 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1012 unsigned long val; 1013 int ret; 1014 1015 if (!fs_info) 1016 return -EPERM; 1017 1018 if (!capable(CAP_SYS_RESOURCE)) 1019 return -EPERM; 1020 1021 ret = kstrtoul(buf, 10, &val); 1022 if (ret) 1023 return ret; 1024 if (val) 1025 return -EINVAL; 1026 1027 WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0); 1028 1029 return len; 1030 } 1031 BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store); 1032 1033 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj, 1034 struct kobj_attribute *a, char *buf) 1035 { 1036 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1037 1038 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); 1039 } 1040 1041 BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show); 1042 1043 static ssize_t quota_override_show(struct kobject *kobj, 1044 struct kobj_attribute *a, char *buf) 1045 { 1046 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1047 int quota_override; 1048 1049 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 1050 return sysfs_emit(buf, "%d\n", quota_override); 1051 } 1052 1053 static ssize_t quota_override_store(struct kobject *kobj, 1054 struct kobj_attribute *a, 1055 const char *buf, size_t len) 1056 { 1057 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1058 unsigned long knob; 1059 int err; 1060 1061 if (!fs_info) 1062 return -EPERM; 1063 1064 if (!capable(CAP_SYS_RESOURCE)) 1065 return -EPERM; 1066 1067 err = kstrtoul(buf, 10, &knob); 1068 if (err) 1069 return err; 1070 if (knob > 1) 1071 return -EINVAL; 1072 1073 if (knob) 1074 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 1075 else 1076 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 1077 1078 return len; 1079 } 1080 1081 BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store); 1082 1083 static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj, 1084 struct kobj_attribute *a, char *buf) 1085 { 1086 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1087 1088 return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid); 1089 } 1090 1091 BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show); 1092 1093 static ssize_t btrfs_checksum_show(struct kobject *kobj, 1094 struct kobj_attribute *a, char *buf) 1095 { 1096 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1097 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy); 1098 1099 return sysfs_emit(buf, "%s (%s)\n", 1100 btrfs_super_csum_name(csum_type), 1101 crypto_shash_driver_name(fs_info->csum_shash)); 1102 } 1103 1104 BTRFS_ATTR(, checksum, btrfs_checksum_show); 1105 1106 static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj, 1107 struct kobj_attribute *a, char *buf) 1108 { 1109 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1110 const char *str; 1111 1112 switch (READ_ONCE(fs_info->exclusive_operation)) { 1113 case BTRFS_EXCLOP_NONE: 1114 str = "none\n"; 1115 break; 1116 case BTRFS_EXCLOP_BALANCE: 1117 str = "balance\n"; 1118 break; 1119 case BTRFS_EXCLOP_BALANCE_PAUSED: 1120 str = "balance paused\n"; 1121 break; 1122 case BTRFS_EXCLOP_DEV_ADD: 1123 str = "device add\n"; 1124 break; 1125 case BTRFS_EXCLOP_DEV_REMOVE: 1126 str = "device remove\n"; 1127 break; 1128 case BTRFS_EXCLOP_DEV_REPLACE: 1129 str = "device replace\n"; 1130 break; 1131 case BTRFS_EXCLOP_RESIZE: 1132 str = "resize\n"; 1133 break; 1134 case BTRFS_EXCLOP_SWAP_ACTIVATE: 1135 str = "swap activate\n"; 1136 break; 1137 default: 1138 str = "UNKNOWN\n"; 1139 break; 1140 } 1141 return sysfs_emit(buf, "%s", str); 1142 } 1143 BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show); 1144 1145 static ssize_t btrfs_generation_show(struct kobject *kobj, 1146 struct kobj_attribute *a, char *buf) 1147 { 1148 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1149 1150 return sysfs_emit(buf, "%llu\n", fs_info->generation); 1151 } 1152 BTRFS_ATTR(, generation, btrfs_generation_show); 1153 1154 static const char * const btrfs_read_policy_name[] = { "pid" }; 1155 1156 static ssize_t btrfs_read_policy_show(struct kobject *kobj, 1157 struct kobj_attribute *a, char *buf) 1158 { 1159 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); 1160 ssize_t ret = 0; 1161 int i; 1162 1163 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) { 1164 if (fs_devices->read_policy == i) 1165 ret += sysfs_emit_at(buf, ret, "%s[%s]", 1166 (ret == 0 ? "" : " "), 1167 btrfs_read_policy_name[i]); 1168 else 1169 ret += sysfs_emit_at(buf, ret, "%s%s", 1170 (ret == 0 ? "" : " "), 1171 btrfs_read_policy_name[i]); 1172 } 1173 1174 ret += sysfs_emit_at(buf, ret, "\n"); 1175 1176 return ret; 1177 } 1178 1179 static ssize_t btrfs_read_policy_store(struct kobject *kobj, 1180 struct kobj_attribute *a, 1181 const char *buf, size_t len) 1182 { 1183 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); 1184 int i; 1185 1186 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) { 1187 if (sysfs_streq(buf, btrfs_read_policy_name[i])) { 1188 if (i != fs_devices->read_policy) { 1189 fs_devices->read_policy = i; 1190 btrfs_info(fs_devices->fs_info, 1191 "read policy set to '%s'", 1192 btrfs_read_policy_name[i]); 1193 } 1194 return len; 1195 } 1196 } 1197 1198 return -EINVAL; 1199 } 1200 BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store); 1201 1202 static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj, 1203 struct kobj_attribute *a, 1204 char *buf) 1205 { 1206 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1207 1208 return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold)); 1209 } 1210 1211 static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj, 1212 struct kobj_attribute *a, 1213 const char *buf, size_t len) 1214 { 1215 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1216 int thresh; 1217 int ret; 1218 1219 ret = kstrtoint(buf, 10, &thresh); 1220 if (ret) 1221 return ret; 1222 1223 if (thresh != 0 && (thresh <= 50 || thresh > 100)) 1224 return -EINVAL; 1225 1226 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh); 1227 1228 return len; 1229 } 1230 BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show, 1231 btrfs_bg_reclaim_threshold_store); 1232 1233 /* 1234 * Per-filesystem information and stats. 1235 * 1236 * Path: /sys/fs/btrfs/<uuid>/ 1237 */ 1238 static const struct attribute *btrfs_attrs[] = { 1239 BTRFS_ATTR_PTR(, label), 1240 BTRFS_ATTR_PTR(, nodesize), 1241 BTRFS_ATTR_PTR(, sectorsize), 1242 BTRFS_ATTR_PTR(, clone_alignment), 1243 BTRFS_ATTR_PTR(, quota_override), 1244 BTRFS_ATTR_PTR(, metadata_uuid), 1245 BTRFS_ATTR_PTR(, checksum), 1246 BTRFS_ATTR_PTR(, exclusive_operation), 1247 BTRFS_ATTR_PTR(, generation), 1248 BTRFS_ATTR_PTR(, read_policy), 1249 BTRFS_ATTR_PTR(, bg_reclaim_threshold), 1250 BTRFS_ATTR_PTR(, commit_stats), 1251 NULL, 1252 }; 1253 1254 static void btrfs_release_fsid_kobj(struct kobject *kobj) 1255 { 1256 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj); 1257 1258 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject)); 1259 complete(&fs_devs->kobj_unregister); 1260 } 1261 1262 static const struct kobj_type btrfs_ktype = { 1263 .sysfs_ops = &kobj_sysfs_ops, 1264 .release = btrfs_release_fsid_kobj, 1265 }; 1266 1267 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj) 1268 { 1269 if (kobj->ktype != &btrfs_ktype) 1270 return NULL; 1271 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj); 1272 } 1273 1274 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj) 1275 { 1276 if (kobj->ktype != &btrfs_ktype) 1277 return NULL; 1278 return to_fs_devs(kobj)->fs_info; 1279 } 1280 1281 static struct kobject *get_btrfs_kobj(struct kobject *kobj) 1282 { 1283 while (kobj) { 1284 if (kobj->ktype == &btrfs_ktype) 1285 return kobj; 1286 kobj = kobj->parent; 1287 } 1288 return NULL; 1289 } 1290 1291 #define NUM_FEATURE_BITS 64 1292 #define BTRFS_FEATURE_NAME_MAX 13 1293 static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX]; 1294 static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS]; 1295 1296 static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) == 1297 ARRAY_SIZE(btrfs_feature_attrs)); 1298 static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) == 1299 ARRAY_SIZE(btrfs_feature_attrs[0])); 1300 1301 static const u64 supported_feature_masks[FEAT_MAX] = { 1302 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP, 1303 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP, 1304 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP, 1305 }; 1306 1307 static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add) 1308 { 1309 int set; 1310 1311 for (set = 0; set < FEAT_MAX; set++) { 1312 int i; 1313 struct attribute *attrs[2]; 1314 struct attribute_group agroup = { 1315 .name = "features", 1316 .attrs = attrs, 1317 }; 1318 u64 features = get_features(fs_info, set); 1319 features &= ~supported_feature_masks[set]; 1320 1321 if (!features) 1322 continue; 1323 1324 attrs[1] = NULL; 1325 for (i = 0; i < NUM_FEATURE_BITS; i++) { 1326 struct btrfs_feature_attr *fa; 1327 1328 if (!(features & (1ULL << i))) 1329 continue; 1330 1331 fa = &btrfs_feature_attrs[set][i]; 1332 attrs[0] = &fa->kobj_attr.attr; 1333 if (add) { 1334 int ret; 1335 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj, 1336 &agroup); 1337 if (ret) 1338 return ret; 1339 } else 1340 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj, 1341 &agroup); 1342 } 1343 1344 } 1345 return 0; 1346 } 1347 1348 static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) 1349 { 1350 if (fs_devs->devinfo_kobj) { 1351 kobject_del(fs_devs->devinfo_kobj); 1352 kobject_put(fs_devs->devinfo_kobj); 1353 fs_devs->devinfo_kobj = NULL; 1354 } 1355 1356 if (fs_devs->devices_kobj) { 1357 kobject_del(fs_devs->devices_kobj); 1358 kobject_put(fs_devs->devices_kobj); 1359 fs_devs->devices_kobj = NULL; 1360 } 1361 1362 if (fs_devs->fsid_kobj.state_initialized) { 1363 kobject_del(&fs_devs->fsid_kobj); 1364 kobject_put(&fs_devs->fsid_kobj); 1365 wait_for_completion(&fs_devs->kobj_unregister); 1366 } 1367 } 1368 1369 /* when fs_devs is NULL it will remove all fsid kobject */ 1370 void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) 1371 { 1372 struct list_head *fs_uuids = btrfs_get_fs_uuids(); 1373 1374 if (fs_devs) { 1375 __btrfs_sysfs_remove_fsid(fs_devs); 1376 return; 1377 } 1378 1379 list_for_each_entry(fs_devs, fs_uuids, fs_list) { 1380 __btrfs_sysfs_remove_fsid(fs_devs); 1381 } 1382 } 1383 1384 static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices) 1385 { 1386 struct btrfs_device *device; 1387 struct btrfs_fs_devices *seed; 1388 1389 list_for_each_entry(device, &fs_devices->devices, dev_list) 1390 btrfs_sysfs_remove_device(device); 1391 1392 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { 1393 list_for_each_entry(device, &seed->devices, dev_list) 1394 btrfs_sysfs_remove_device(device); 1395 } 1396 } 1397 1398 void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info) 1399 { 1400 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; 1401 1402 sysfs_remove_link(fsid_kobj, "bdi"); 1403 1404 if (fs_info->space_info_kobj) { 1405 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); 1406 kobject_del(fs_info->space_info_kobj); 1407 kobject_put(fs_info->space_info_kobj); 1408 } 1409 if (fs_info->discard_kobj) { 1410 sysfs_remove_files(fs_info->discard_kobj, discard_attrs); 1411 kobject_del(fs_info->discard_kobj); 1412 kobject_put(fs_info->discard_kobj); 1413 } 1414 #ifdef CONFIG_BTRFS_DEBUG 1415 if (fs_info->debug_kobj) { 1416 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); 1417 kobject_del(fs_info->debug_kobj); 1418 kobject_put(fs_info->debug_kobj); 1419 } 1420 #endif 1421 addrm_unknown_feature_attrs(fs_info, false); 1422 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group); 1423 sysfs_remove_files(fsid_kobj, btrfs_attrs); 1424 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices); 1425 } 1426 1427 static const char * const btrfs_feature_set_names[FEAT_MAX] = { 1428 [FEAT_COMPAT] = "compat", 1429 [FEAT_COMPAT_RO] = "compat_ro", 1430 [FEAT_INCOMPAT] = "incompat", 1431 }; 1432 1433 const char *btrfs_feature_set_name(enum btrfs_feature_set set) 1434 { 1435 return btrfs_feature_set_names[set]; 1436 } 1437 1438 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags) 1439 { 1440 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */ 1441 int len = 0; 1442 int i; 1443 char *str; 1444 1445 str = kmalloc(bufsize, GFP_KERNEL); 1446 if (!str) 1447 return str; 1448 1449 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 1450 const char *name; 1451 1452 if (!(flags & (1ULL << i))) 1453 continue; 1454 1455 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name; 1456 len += scnprintf(str + len, bufsize - len, "%s%s", 1457 len ? "," : "", name); 1458 } 1459 1460 return str; 1461 } 1462 1463 static void init_feature_attrs(void) 1464 { 1465 struct btrfs_feature_attr *fa; 1466 int set, i; 1467 1468 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs)); 1469 memset(btrfs_unknown_feature_names, 0, 1470 sizeof(btrfs_unknown_feature_names)); 1471 1472 for (i = 0; btrfs_supported_feature_attrs[i]; i++) { 1473 struct btrfs_feature_attr *sfa; 1474 struct attribute *a = btrfs_supported_feature_attrs[i]; 1475 int bit; 1476 sfa = attr_to_btrfs_feature_attr(a); 1477 bit = ilog2(sfa->feature_bit); 1478 fa = &btrfs_feature_attrs[sfa->feature_set][bit]; 1479 1480 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name; 1481 } 1482 1483 for (set = 0; set < FEAT_MAX; set++) { 1484 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 1485 char *name = btrfs_unknown_feature_names[set][i]; 1486 fa = &btrfs_feature_attrs[set][i]; 1487 1488 if (fa->kobj_attr.attr.name) 1489 continue; 1490 1491 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u", 1492 btrfs_feature_set_names[set], i); 1493 1494 fa->kobj_attr.attr.name = name; 1495 fa->kobj_attr.attr.mode = S_IRUGO; 1496 fa->feature_set = set; 1497 fa->feature_bit = 1ULL << i; 1498 } 1499 } 1500 } 1501 1502 /* 1503 * Create a sysfs entry for a given block group type at path 1504 * /sys/fs/btrfs/UUID/allocation/data/TYPE 1505 */ 1506 void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache) 1507 { 1508 struct btrfs_fs_info *fs_info = cache->fs_info; 1509 struct btrfs_space_info *space_info = cache->space_info; 1510 struct raid_kobject *rkobj; 1511 const int index = btrfs_bg_flags_to_raid_index(cache->flags); 1512 unsigned int nofs_flag; 1513 int ret; 1514 1515 /* 1516 * Setup a NOFS context because kobject_add(), deep in its call chain, 1517 * does GFP_KERNEL allocations, and we are often called in a context 1518 * where if reclaim is triggered we can deadlock (we are either holding 1519 * a transaction handle or some lock required for a transaction 1520 * commit). 1521 */ 1522 nofs_flag = memalloc_nofs_save(); 1523 1524 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS); 1525 if (!rkobj) { 1526 memalloc_nofs_restore(nofs_flag); 1527 btrfs_warn(cache->fs_info, 1528 "couldn't alloc memory for raid level kobject"); 1529 return; 1530 } 1531 1532 rkobj->flags = cache->flags; 1533 kobject_init(&rkobj->kobj, &btrfs_raid_ktype); 1534 1535 /* 1536 * We call this either on mount, or if we've created a block group for a 1537 * new index type while running (i.e. when restriping). The running 1538 * case is tricky because we could race with other threads, so we need 1539 * to have this check to make sure we didn't already init the kobject. 1540 * 1541 * We don't have to protect on the free side because it only happens on 1542 * unmount. 1543 */ 1544 spin_lock(&space_info->lock); 1545 if (space_info->block_group_kobjs[index]) { 1546 spin_unlock(&space_info->lock); 1547 kobject_put(&rkobj->kobj); 1548 return; 1549 } else { 1550 space_info->block_group_kobjs[index] = &rkobj->kobj; 1551 } 1552 spin_unlock(&space_info->lock); 1553 1554 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s", 1555 btrfs_bg_type_to_raid_name(rkobj->flags)); 1556 memalloc_nofs_restore(nofs_flag); 1557 if (ret) { 1558 spin_lock(&space_info->lock); 1559 space_info->block_group_kobjs[index] = NULL; 1560 spin_unlock(&space_info->lock); 1561 kobject_put(&rkobj->kobj); 1562 btrfs_warn(fs_info, 1563 "failed to add kobject for block cache, ignoring"); 1564 return; 1565 } 1566 } 1567 1568 /* 1569 * Remove sysfs directories for all block group types of a given space info and 1570 * the space info as well 1571 */ 1572 void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info) 1573 { 1574 int i; 1575 1576 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { 1577 struct kobject *kobj; 1578 1579 kobj = space_info->block_group_kobjs[i]; 1580 space_info->block_group_kobjs[i] = NULL; 1581 if (kobj) { 1582 kobject_del(kobj); 1583 kobject_put(kobj); 1584 } 1585 } 1586 kobject_del(&space_info->kobj); 1587 kobject_put(&space_info->kobj); 1588 } 1589 1590 static const char *alloc_name(u64 flags) 1591 { 1592 switch (flags) { 1593 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA: 1594 return "mixed"; 1595 case BTRFS_BLOCK_GROUP_METADATA: 1596 return "metadata"; 1597 case BTRFS_BLOCK_GROUP_DATA: 1598 return "data"; 1599 case BTRFS_BLOCK_GROUP_SYSTEM: 1600 return "system"; 1601 default: 1602 WARN_ON(1); 1603 return "invalid-combination"; 1604 } 1605 } 1606 1607 /* 1608 * Create a sysfs entry for a space info type at path 1609 * /sys/fs/btrfs/UUID/allocation/TYPE 1610 */ 1611 int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info, 1612 struct btrfs_space_info *space_info) 1613 { 1614 int ret; 1615 1616 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype, 1617 fs_info->space_info_kobj, "%s", 1618 alloc_name(space_info->flags)); 1619 if (ret) { 1620 kobject_put(&space_info->kobj); 1621 return ret; 1622 } 1623 1624 return 0; 1625 } 1626 1627 void btrfs_sysfs_remove_device(struct btrfs_device *device) 1628 { 1629 struct kobject *devices_kobj; 1630 1631 /* 1632 * Seed fs_devices devices_kobj aren't used, fetch kobject from the 1633 * fs_info::fs_devices. 1634 */ 1635 devices_kobj = device->fs_info->fs_devices->devices_kobj; 1636 ASSERT(devices_kobj); 1637 1638 if (device->bdev) 1639 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name); 1640 1641 if (device->devid_kobj.state_initialized) { 1642 kobject_del(&device->devid_kobj); 1643 kobject_put(&device->devid_kobj); 1644 wait_for_completion(&device->kobj_unregister); 1645 } 1646 } 1647 1648 static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj, 1649 struct kobj_attribute *a, 1650 char *buf) 1651 { 1652 int val; 1653 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1654 devid_kobj); 1655 1656 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 1657 1658 return sysfs_emit(buf, "%d\n", val); 1659 } 1660 BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show); 1661 1662 static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj, 1663 struct kobj_attribute *a, char *buf) 1664 { 1665 int val; 1666 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1667 devid_kobj); 1668 1669 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); 1670 1671 return sysfs_emit(buf, "%d\n", val); 1672 } 1673 BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show); 1674 1675 static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj, 1676 struct kobj_attribute *a, 1677 char *buf) 1678 { 1679 int val; 1680 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1681 devid_kobj); 1682 1683 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 1684 1685 return sysfs_emit(buf, "%d\n", val); 1686 } 1687 BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show); 1688 1689 static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj, 1690 struct kobj_attribute *a, 1691 char *buf) 1692 { 1693 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1694 devid_kobj); 1695 1696 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max)); 1697 } 1698 1699 static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj, 1700 struct kobj_attribute *a, 1701 const char *buf, size_t len) 1702 { 1703 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1704 devid_kobj); 1705 char *endptr; 1706 unsigned long long limit; 1707 1708 limit = memparse(buf, &endptr); 1709 WRITE_ONCE(device->scrub_speed_max, limit); 1710 return len; 1711 } 1712 BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show, 1713 btrfs_devinfo_scrub_speed_max_store); 1714 1715 static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj, 1716 struct kobj_attribute *a, char *buf) 1717 { 1718 int val; 1719 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1720 devid_kobj); 1721 1722 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 1723 1724 return sysfs_emit(buf, "%d\n", val); 1725 } 1726 BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show); 1727 1728 static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj, 1729 struct kobj_attribute *a, char *buf) 1730 { 1731 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1732 devid_kobj); 1733 1734 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid); 1735 } 1736 BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show); 1737 1738 static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj, 1739 struct kobj_attribute *a, char *buf) 1740 { 1741 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1742 devid_kobj); 1743 1744 if (!device->dev_stats_valid) 1745 return sysfs_emit(buf, "invalid\n"); 1746 1747 /* 1748 * Print all at once so we get a snapshot of all values from the same 1749 * time. Keep them in sync and in order of definition of 1750 * btrfs_dev_stat_values. 1751 */ 1752 return sysfs_emit(buf, 1753 "write_errs %d\n" 1754 "read_errs %d\n" 1755 "flush_errs %d\n" 1756 "corruption_errs %d\n" 1757 "generation_errs %d\n", 1758 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS), 1759 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS), 1760 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS), 1761 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS), 1762 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS)); 1763 } 1764 BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show); 1765 1766 /* 1767 * Information about one device. 1768 * 1769 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/ 1770 */ 1771 static struct attribute *devid_attrs[] = { 1772 BTRFS_ATTR_PTR(devid, error_stats), 1773 BTRFS_ATTR_PTR(devid, fsid), 1774 BTRFS_ATTR_PTR(devid, in_fs_metadata), 1775 BTRFS_ATTR_PTR(devid, missing), 1776 BTRFS_ATTR_PTR(devid, replace_target), 1777 BTRFS_ATTR_PTR(devid, scrub_speed_max), 1778 BTRFS_ATTR_PTR(devid, writeable), 1779 NULL 1780 }; 1781 ATTRIBUTE_GROUPS(devid); 1782 1783 static void btrfs_release_devid_kobj(struct kobject *kobj) 1784 { 1785 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1786 devid_kobj); 1787 1788 memset(&device->devid_kobj, 0, sizeof(struct kobject)); 1789 complete(&device->kobj_unregister); 1790 } 1791 1792 static const struct kobj_type devid_ktype = { 1793 .sysfs_ops = &kobj_sysfs_ops, 1794 .default_groups = devid_groups, 1795 .release = btrfs_release_devid_kobj, 1796 }; 1797 1798 int btrfs_sysfs_add_device(struct btrfs_device *device) 1799 { 1800 int ret; 1801 unsigned int nofs_flag; 1802 struct kobject *devices_kobj; 1803 struct kobject *devinfo_kobj; 1804 1805 /* 1806 * Make sure we use the fs_info::fs_devices to fetch the kobjects even 1807 * for the seed fs_devices 1808 */ 1809 devices_kobj = device->fs_info->fs_devices->devices_kobj; 1810 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj; 1811 ASSERT(devices_kobj); 1812 ASSERT(devinfo_kobj); 1813 1814 nofs_flag = memalloc_nofs_save(); 1815 1816 if (device->bdev) { 1817 struct kobject *disk_kobj = bdev_kobj(device->bdev); 1818 1819 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name); 1820 if (ret) { 1821 btrfs_warn(device->fs_info, 1822 "creating sysfs device link for devid %llu failed: %d", 1823 device->devid, ret); 1824 goto out; 1825 } 1826 } 1827 1828 init_completion(&device->kobj_unregister); 1829 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype, 1830 devinfo_kobj, "%llu", device->devid); 1831 if (ret) { 1832 kobject_put(&device->devid_kobj); 1833 btrfs_warn(device->fs_info, 1834 "devinfo init for devid %llu failed: %d", 1835 device->devid, ret); 1836 } 1837 1838 out: 1839 memalloc_nofs_restore(nofs_flag); 1840 return ret; 1841 } 1842 1843 static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices) 1844 { 1845 int ret; 1846 struct btrfs_device *device; 1847 struct btrfs_fs_devices *seed; 1848 1849 list_for_each_entry(device, &fs_devices->devices, dev_list) { 1850 ret = btrfs_sysfs_add_device(device); 1851 if (ret) 1852 goto fail; 1853 } 1854 1855 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { 1856 list_for_each_entry(device, &seed->devices, dev_list) { 1857 ret = btrfs_sysfs_add_device(device); 1858 if (ret) 1859 goto fail; 1860 } 1861 } 1862 1863 return 0; 1864 1865 fail: 1866 btrfs_sysfs_remove_fs_devices(fs_devices); 1867 return ret; 1868 } 1869 1870 void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action) 1871 { 1872 int ret; 1873 1874 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 1875 if (ret) 1876 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n", 1877 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 1878 &disk_to_dev(bdev->bd_disk)->kobj); 1879 } 1880 1881 void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices) 1882 1883 { 1884 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE]; 1885 1886 /* 1887 * Sprouting changes fsid of the mounted filesystem, rename the fsid 1888 * directory 1889 */ 1890 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid); 1891 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf)) 1892 btrfs_warn(fs_devices->fs_info, 1893 "sysfs: failed to create fsid for sprout"); 1894 } 1895 1896 void btrfs_sysfs_update_devid(struct btrfs_device *device) 1897 { 1898 char tmp[24]; 1899 1900 snprintf(tmp, sizeof(tmp), "%llu", device->devid); 1901 1902 if (kobject_rename(&device->devid_kobj, tmp)) 1903 btrfs_warn(device->fs_devices->fs_info, 1904 "sysfs: failed to update devid for %llu", 1905 device->devid); 1906 } 1907 1908 /* /sys/fs/btrfs/ entry */ 1909 static struct kset *btrfs_kset; 1910 1911 /* 1912 * Creates: 1913 * /sys/fs/btrfs/UUID 1914 * 1915 * Can be called by the device discovery thread. 1916 */ 1917 int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs) 1918 { 1919 int error; 1920 1921 init_completion(&fs_devs->kobj_unregister); 1922 fs_devs->fsid_kobj.kset = btrfs_kset; 1923 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL, 1924 "%pU", fs_devs->fsid); 1925 if (error) { 1926 kobject_put(&fs_devs->fsid_kobj); 1927 return error; 1928 } 1929 1930 fs_devs->devices_kobj = kobject_create_and_add("devices", 1931 &fs_devs->fsid_kobj); 1932 if (!fs_devs->devices_kobj) { 1933 btrfs_err(fs_devs->fs_info, 1934 "failed to init sysfs device interface"); 1935 btrfs_sysfs_remove_fsid(fs_devs); 1936 return -ENOMEM; 1937 } 1938 1939 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo", 1940 &fs_devs->fsid_kobj); 1941 if (!fs_devs->devinfo_kobj) { 1942 btrfs_err(fs_devs->fs_info, 1943 "failed to init sysfs devinfo kobject"); 1944 btrfs_sysfs_remove_fsid(fs_devs); 1945 return -ENOMEM; 1946 } 1947 1948 return 0; 1949 } 1950 1951 int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info) 1952 { 1953 int error; 1954 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices; 1955 struct kobject *fsid_kobj = &fs_devs->fsid_kobj; 1956 1957 error = btrfs_sysfs_add_fs_devices(fs_devs); 1958 if (error) 1959 return error; 1960 1961 error = sysfs_create_files(fsid_kobj, btrfs_attrs); 1962 if (error) { 1963 btrfs_sysfs_remove_fs_devices(fs_devs); 1964 return error; 1965 } 1966 1967 error = sysfs_create_group(fsid_kobj, 1968 &btrfs_feature_attr_group); 1969 if (error) 1970 goto failure; 1971 1972 #ifdef CONFIG_BTRFS_DEBUG 1973 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj); 1974 if (!fs_info->debug_kobj) { 1975 error = -ENOMEM; 1976 goto failure; 1977 } 1978 1979 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); 1980 if (error) 1981 goto failure; 1982 #endif 1983 1984 /* Discard directory */ 1985 fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj); 1986 if (!fs_info->discard_kobj) { 1987 error = -ENOMEM; 1988 goto failure; 1989 } 1990 1991 error = sysfs_create_files(fs_info->discard_kobj, discard_attrs); 1992 if (error) 1993 goto failure; 1994 1995 error = addrm_unknown_feature_attrs(fs_info, true); 1996 if (error) 1997 goto failure; 1998 1999 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi"); 2000 if (error) 2001 goto failure; 2002 2003 fs_info->space_info_kobj = kobject_create_and_add("allocation", 2004 fsid_kobj); 2005 if (!fs_info->space_info_kobj) { 2006 error = -ENOMEM; 2007 goto failure; 2008 } 2009 2010 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs); 2011 if (error) 2012 goto failure; 2013 2014 return 0; 2015 failure: 2016 btrfs_sysfs_remove_mounted(fs_info); 2017 return error; 2018 } 2019 2020 static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj, 2021 struct kobj_attribute *a, 2022 char *buf) 2023 { 2024 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2025 bool enabled; 2026 2027 spin_lock(&fs_info->qgroup_lock); 2028 enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON; 2029 spin_unlock(&fs_info->qgroup_lock); 2030 2031 return sysfs_emit(buf, "%d\n", enabled); 2032 } 2033 BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show); 2034 2035 static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj, 2036 struct kobj_attribute *a, 2037 char *buf) 2038 { 2039 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2040 bool inconsistent; 2041 2042 spin_lock(&fs_info->qgroup_lock); 2043 inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT); 2044 spin_unlock(&fs_info->qgroup_lock); 2045 2046 return sysfs_emit(buf, "%d\n", inconsistent); 2047 } 2048 BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show); 2049 2050 static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj, 2051 struct kobj_attribute *a, 2052 char *buf) 2053 { 2054 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2055 u8 result; 2056 2057 spin_lock(&fs_info->qgroup_lock); 2058 result = fs_info->qgroup_drop_subtree_thres; 2059 spin_unlock(&fs_info->qgroup_lock); 2060 2061 return sysfs_emit(buf, "%d\n", result); 2062 } 2063 2064 static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj, 2065 struct kobj_attribute *a, 2066 const char *buf, size_t len) 2067 { 2068 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2069 u8 new_thres; 2070 int ret; 2071 2072 ret = kstrtou8(buf, 10, &new_thres); 2073 if (ret) 2074 return -EINVAL; 2075 2076 if (new_thres > BTRFS_MAX_LEVEL) 2077 return -EINVAL; 2078 2079 spin_lock(&fs_info->qgroup_lock); 2080 fs_info->qgroup_drop_subtree_thres = new_thres; 2081 spin_unlock(&fs_info->qgroup_lock); 2082 2083 return len; 2084 } 2085 BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show, 2086 qgroup_drop_subtree_thres_store); 2087 2088 /* 2089 * Qgroups global info 2090 * 2091 * Path: /sys/fs/btrfs/<uuid>/qgroups/ 2092 */ 2093 static struct attribute *qgroups_attrs[] = { 2094 BTRFS_ATTR_PTR(qgroups, enabled), 2095 BTRFS_ATTR_PTR(qgroups, inconsistent), 2096 BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold), 2097 NULL 2098 }; 2099 ATTRIBUTE_GROUPS(qgroups); 2100 2101 static void qgroups_release(struct kobject *kobj) 2102 { 2103 kfree(kobj); 2104 } 2105 2106 static const struct kobj_type qgroups_ktype = { 2107 .sysfs_ops = &kobj_sysfs_ops, 2108 .default_groups = qgroups_groups, 2109 .release = qgroups_release, 2110 }; 2111 2112 static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj) 2113 { 2114 return to_fs_info(kobj->parent->parent); 2115 } 2116 2117 #define QGROUP_ATTR(_member, _show_name) \ 2118 static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \ 2119 struct kobj_attribute *a, \ 2120 char *buf) \ 2121 { \ 2122 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ 2123 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ 2124 struct btrfs_qgroup, kobj); \ 2125 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \ 2126 } \ 2127 BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member) 2128 2129 #define QGROUP_RSV_ATTR(_name, _type) \ 2130 static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \ 2131 struct kobj_attribute *a, \ 2132 char *buf) \ 2133 { \ 2134 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ 2135 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ 2136 struct btrfs_qgroup, kobj); \ 2137 return btrfs_show_u64(&qgroup->rsv.values[_type], \ 2138 &fs_info->qgroup_lock, buf); \ 2139 } \ 2140 BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name) 2141 2142 QGROUP_ATTR(rfer, referenced); 2143 QGROUP_ATTR(excl, exclusive); 2144 QGROUP_ATTR(max_rfer, max_referenced); 2145 QGROUP_ATTR(max_excl, max_exclusive); 2146 QGROUP_ATTR(lim_flags, limit_flags); 2147 QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA); 2148 QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS); 2149 QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC); 2150 2151 /* 2152 * Qgroup information. 2153 * 2154 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/ 2155 */ 2156 static struct attribute *qgroup_attrs[] = { 2157 BTRFS_ATTR_PTR(qgroup, referenced), 2158 BTRFS_ATTR_PTR(qgroup, exclusive), 2159 BTRFS_ATTR_PTR(qgroup, max_referenced), 2160 BTRFS_ATTR_PTR(qgroup, max_exclusive), 2161 BTRFS_ATTR_PTR(qgroup, limit_flags), 2162 BTRFS_ATTR_PTR(qgroup, rsv_data), 2163 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans), 2164 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc), 2165 NULL 2166 }; 2167 ATTRIBUTE_GROUPS(qgroup); 2168 2169 static void qgroup_release(struct kobject *kobj) 2170 { 2171 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj); 2172 2173 memset(&qgroup->kobj, 0, sizeof(*kobj)); 2174 } 2175 2176 static const struct kobj_type qgroup_ktype = { 2177 .sysfs_ops = &kobj_sysfs_ops, 2178 .release = qgroup_release, 2179 .default_groups = qgroup_groups, 2180 }; 2181 2182 int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info, 2183 struct btrfs_qgroup *qgroup) 2184 { 2185 struct kobject *qgroups_kobj = fs_info->qgroups_kobj; 2186 int ret; 2187 2188 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2189 return 0; 2190 if (qgroup->kobj.state_initialized) 2191 return 0; 2192 if (!qgroups_kobj) 2193 return -EINVAL; 2194 2195 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj, 2196 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid), 2197 btrfs_qgroup_subvolid(qgroup->qgroupid)); 2198 if (ret < 0) 2199 kobject_put(&qgroup->kobj); 2200 2201 return ret; 2202 } 2203 2204 void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info) 2205 { 2206 struct btrfs_qgroup *qgroup; 2207 struct btrfs_qgroup *next; 2208 2209 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2210 return; 2211 2212 rbtree_postorder_for_each_entry_safe(qgroup, next, 2213 &fs_info->qgroup_tree, node) 2214 btrfs_sysfs_del_one_qgroup(fs_info, qgroup); 2215 if (fs_info->qgroups_kobj) { 2216 kobject_del(fs_info->qgroups_kobj); 2217 kobject_put(fs_info->qgroups_kobj); 2218 fs_info->qgroups_kobj = NULL; 2219 } 2220 } 2221 2222 /* Called when qgroups get initialized, thus there is no need for locking */ 2223 int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info) 2224 { 2225 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; 2226 struct btrfs_qgroup *qgroup; 2227 struct btrfs_qgroup *next; 2228 int ret = 0; 2229 2230 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2231 return 0; 2232 2233 ASSERT(fsid_kobj); 2234 if (fs_info->qgroups_kobj) 2235 return 0; 2236 2237 fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL); 2238 if (!fs_info->qgroups_kobj) 2239 return -ENOMEM; 2240 2241 ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype, 2242 fsid_kobj, "qgroups"); 2243 if (ret < 0) 2244 goto out; 2245 2246 rbtree_postorder_for_each_entry_safe(qgroup, next, 2247 &fs_info->qgroup_tree, node) { 2248 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); 2249 if (ret < 0) 2250 goto out; 2251 } 2252 2253 out: 2254 if (ret < 0) 2255 btrfs_sysfs_del_qgroups(fs_info); 2256 return ret; 2257 } 2258 2259 void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info, 2260 struct btrfs_qgroup *qgroup) 2261 { 2262 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2263 return; 2264 2265 if (qgroup->kobj.state_initialized) { 2266 kobject_del(&qgroup->kobj); 2267 kobject_put(&qgroup->kobj); 2268 } 2269 } 2270 2271 /* 2272 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current 2273 * values in superblock. Call after any changes to incompat/compat_ro flags 2274 */ 2275 void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info) 2276 { 2277 struct kobject *fsid_kobj; 2278 int ret; 2279 2280 if (!fs_info) 2281 return; 2282 2283 fsid_kobj = &fs_info->fs_devices->fsid_kobj; 2284 if (!fsid_kobj->state_initialized) 2285 return; 2286 2287 ret = sysfs_update_group(fsid_kobj, &btrfs_feature_attr_group); 2288 if (ret < 0) 2289 btrfs_warn(fs_info, 2290 "failed to update /sys/fs/btrfs/%pU/features: %d", 2291 fs_info->fs_devices->fsid, ret); 2292 } 2293 2294 int __init btrfs_init_sysfs(void) 2295 { 2296 int ret; 2297 2298 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); 2299 if (!btrfs_kset) 2300 return -ENOMEM; 2301 2302 init_feature_attrs(); 2303 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2304 if (ret) 2305 goto out2; 2306 ret = sysfs_merge_group(&btrfs_kset->kobj, 2307 &btrfs_static_feature_attr_group); 2308 if (ret) 2309 goto out_remove_group; 2310 2311 #ifdef CONFIG_BTRFS_DEBUG 2312 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); 2313 if (ret) { 2314 sysfs_unmerge_group(&btrfs_kset->kobj, 2315 &btrfs_static_feature_attr_group); 2316 goto out_remove_group; 2317 } 2318 #endif 2319 2320 return 0; 2321 2322 out_remove_group: 2323 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2324 out2: 2325 kset_unregister(btrfs_kset); 2326 2327 return ret; 2328 } 2329 2330 void __cold btrfs_exit_sysfs(void) 2331 { 2332 sysfs_unmerge_group(&btrfs_kset->kobj, 2333 &btrfs_static_feature_attr_group); 2334 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2335 #ifdef CONFIG_BTRFS_DEBUG 2336 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); 2337 #endif 2338 kset_unregister(btrfs_kset); 2339 } 2340