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 <linux/list.h> 13#include <crypto/hash.h> 14#include "messages.h" 15#include "ctree.h" 16#include "discard.h" 17#include "disk-io.h" 18#include "send.h" 19#include "transaction.h" 20#include "sysfs.h" 21#include "volumes.h" 22#include "space-info.h" 23#include "block-group.h" 24#include "qgroup.h" 25#include "misc.h" 26#include "fs.h" 27#include "accessors.h" 28 29/* 30 * Structure name Path 31 * -------------------------------------------------------------------------- 32 * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features 33 * btrfs_supported_feature_attrs /sys/fs/btrfs/features and 34 * /sys/fs/btrfs/<uuid>/features 35 * btrfs_attrs /sys/fs/btrfs/<uuid> 36 * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid> 37 * allocation_attrs /sys/fs/btrfs/<uuid>/allocation 38 * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid> 39 * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type> 40 * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile> 41 * discard_attrs /sys/fs/btrfs/<uuid>/discard 42 * 43 * When built with BTRFS_CONFIG_DEBUG: 44 * 45 * btrfs_debug_feature_attrs /sys/fs/btrfs/debug 46 * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug 47 */ 48 49struct btrfs_feature_attr { 50 struct kobj_attribute kobj_attr; 51 enum btrfs_feature_set feature_set; 52 u64 feature_bit; 53}; 54 55/* For raid type sysfs entries */ 56struct raid_kobject { 57 u64 flags; 58 struct kobject kobj; 59}; 60 61#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \ 62{ \ 63 .attr = { .name = __stringify(_name), .mode = _mode }, \ 64 .show = _show, \ 65 .store = _store, \ 66} 67 68#define BTRFS_ATTR_W(_prefix, _name, _store) \ 69 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ 70 __INIT_KOBJ_ATTR(_name, 0200, NULL, _store) 71 72#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \ 73 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ 74 __INIT_KOBJ_ATTR(_name, 0644, _show, _store) 75 76#define BTRFS_ATTR(_prefix, _name, _show) \ 77 static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ 78 __INIT_KOBJ_ATTR(_name, 0444, _show, NULL) 79 80#define BTRFS_ATTR_PTR(_prefix, _name) \ 81 (&btrfs_attr_##_prefix##_##_name.attr) 82 83#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \ 84static struct btrfs_feature_attr btrfs_attr_features_##_name = { \ 85 .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \ 86 btrfs_feature_attr_show, \ 87 btrfs_feature_attr_store), \ 88 .feature_set = _feature_set, \ 89 .feature_bit = _feature_prefix ##_## _feature_bit, \ 90} 91#define BTRFS_FEAT_ATTR_PTR(_name) \ 92 (&btrfs_attr_features_##_name.kobj_attr.attr) 93 94#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \ 95 BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature) 96#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \ 97 BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature) 98#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \ 99 BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature) 100 101static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj); 102static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj); 103static struct kobject *get_btrfs_kobj(struct kobject *kobj); 104 105static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a) 106{ 107 return container_of(a, struct btrfs_feature_attr, kobj_attr); 108} 109 110static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr) 111{ 112 return container_of(attr, struct kobj_attribute, attr); 113} 114 115static struct btrfs_feature_attr *attr_to_btrfs_feature_attr( 116 struct attribute *attr) 117{ 118 return to_btrfs_feature_attr(attr_to_btrfs_attr(attr)); 119} 120 121static u64 get_features(struct btrfs_fs_info *fs_info, 122 enum btrfs_feature_set set) 123{ 124 struct btrfs_super_block *disk_super = fs_info->super_copy; 125 if (set == FEAT_COMPAT) 126 return btrfs_super_compat_flags(disk_super); 127 else if (set == FEAT_COMPAT_RO) 128 return btrfs_super_compat_ro_flags(disk_super); 129 else 130 return btrfs_super_incompat_flags(disk_super); 131} 132 133static void set_features(struct btrfs_fs_info *fs_info, 134 enum btrfs_feature_set set, u64 features) 135{ 136 struct btrfs_super_block *disk_super = fs_info->super_copy; 137 if (set == FEAT_COMPAT) 138 btrfs_set_super_compat_flags(disk_super, features); 139 else if (set == FEAT_COMPAT_RO) 140 btrfs_set_super_compat_ro_flags(disk_super, features); 141 else 142 btrfs_set_super_incompat_flags(disk_super, features); 143} 144 145static int can_modify_feature(struct btrfs_feature_attr *fa) 146{ 147 int val = 0; 148 u64 set, clear; 149 switch (fa->feature_set) { 150 case FEAT_COMPAT: 151 set = BTRFS_FEATURE_COMPAT_SAFE_SET; 152 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR; 153 break; 154 case FEAT_COMPAT_RO: 155 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET; 156 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR; 157 break; 158 case FEAT_INCOMPAT: 159 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET; 160 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR; 161 break; 162 default: 163 pr_warn("btrfs: sysfs: unknown feature set %d\n", 164 fa->feature_set); 165 return 0; 166 } 167 168 if (set & fa->feature_bit) 169 val |= 1; 170 if (clear & fa->feature_bit) 171 val |= 2; 172 173 return val; 174} 175 176static ssize_t btrfs_feature_attr_show(struct kobject *kobj, 177 struct kobj_attribute *a, char *buf) 178{ 179 int val = 0; 180 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 181 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a); 182 if (fs_info) { 183 u64 features = get_features(fs_info, fa->feature_set); 184 if (features & fa->feature_bit) 185 val = 1; 186 } else 187 val = can_modify_feature(fa); 188 189 return sysfs_emit(buf, "%d\n", val); 190} 191 192static ssize_t btrfs_feature_attr_store(struct kobject *kobj, 193 struct kobj_attribute *a, 194 const char *buf, size_t count) 195{ 196 struct btrfs_fs_info *fs_info; 197 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a); 198 u64 features, set, clear; 199 unsigned long val; 200 int ret; 201 202 fs_info = to_fs_info(kobj); 203 if (!fs_info) 204 return -EPERM; 205 206 if (sb_rdonly(fs_info->sb)) 207 return -EROFS; 208 209 ret = kstrtoul(skip_spaces(buf), 0, &val); 210 if (ret) 211 return ret; 212 213 if (fa->feature_set == FEAT_COMPAT) { 214 set = BTRFS_FEATURE_COMPAT_SAFE_SET; 215 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR; 216 } else if (fa->feature_set == FEAT_COMPAT_RO) { 217 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET; 218 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR; 219 } else { 220 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET; 221 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR; 222 } 223 224 features = get_features(fs_info, fa->feature_set); 225 226 /* Nothing to do */ 227 if ((val && (features & fa->feature_bit)) || 228 (!val && !(features & fa->feature_bit))) 229 return count; 230 231 if ((val && !(set & fa->feature_bit)) || 232 (!val && !(clear & fa->feature_bit))) { 233 btrfs_info(fs_info, 234 "%sabling feature %s on mounted fs is not supported.", 235 val ? "En" : "Dis", fa->kobj_attr.attr.name); 236 return -EPERM; 237 } 238 239 btrfs_info(fs_info, "%s %s feature flag", 240 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name); 241 242 spin_lock(&fs_info->super_lock); 243 features = get_features(fs_info, fa->feature_set); 244 if (val) 245 features |= fa->feature_bit; 246 else 247 features &= ~fa->feature_bit; 248 set_features(fs_info, fa->feature_set, features); 249 spin_unlock(&fs_info->super_lock); 250 251 /* 252 * We don't want to do full transaction commit from inside sysfs 253 */ 254 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags); 255 wake_up_process(fs_info->transaction_kthread); 256 257 return count; 258} 259 260static umode_t btrfs_feature_visible(struct kobject *kobj, 261 struct attribute *attr, int unused) 262{ 263 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 264 umode_t mode = attr->mode; 265 266 if (fs_info) { 267 struct btrfs_feature_attr *fa; 268 u64 features; 269 270 fa = attr_to_btrfs_feature_attr(attr); 271 features = get_features(fs_info, fa->feature_set); 272 273 if (can_modify_feature(fa)) 274 mode |= S_IWUSR; 275 else if (!(features & fa->feature_bit)) 276 mode = 0; 277 } 278 279 return mode; 280} 281 282BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL); 283BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS); 284BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO); 285BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD); 286BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF); 287BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56); 288BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA); 289BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES); 290BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID); 291BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE); 292BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE); 293BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34); 294BTRFS_FEAT_ATTR_INCOMPAT(simple_quota, SIMPLE_QUOTA); 295#ifdef CONFIG_BLK_DEV_ZONED 296BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED); 297#endif 298#ifdef CONFIG_BTRFS_DEBUG 299/* Remove once support for extent tree v2 is feature complete */ 300BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2); 301/* Remove once support for raid stripe tree is feature complete. */ 302BTRFS_FEAT_ATTR_INCOMPAT(raid_stripe_tree, RAID_STRIPE_TREE); 303#endif 304#ifdef CONFIG_FS_VERITY 305BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY); 306#endif 307 308/* 309 * Features which depend on feature bits and may differ between each fs. 310 * 311 * /sys/fs/btrfs/features - all available features implemented by this version 312 * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or 313 * can be changed on a mounted filesystem. 314 */ 315static struct attribute *btrfs_supported_feature_attrs[] = { 316 BTRFS_FEAT_ATTR_PTR(default_subvol), 317 BTRFS_FEAT_ATTR_PTR(mixed_groups), 318 BTRFS_FEAT_ATTR_PTR(compress_lzo), 319 BTRFS_FEAT_ATTR_PTR(compress_zstd), 320 BTRFS_FEAT_ATTR_PTR(extended_iref), 321 BTRFS_FEAT_ATTR_PTR(raid56), 322 BTRFS_FEAT_ATTR_PTR(skinny_metadata), 323 BTRFS_FEAT_ATTR_PTR(no_holes), 324 BTRFS_FEAT_ATTR_PTR(metadata_uuid), 325 BTRFS_FEAT_ATTR_PTR(free_space_tree), 326 BTRFS_FEAT_ATTR_PTR(raid1c34), 327 BTRFS_FEAT_ATTR_PTR(block_group_tree), 328 BTRFS_FEAT_ATTR_PTR(simple_quota), 329#ifdef CONFIG_BLK_DEV_ZONED 330 BTRFS_FEAT_ATTR_PTR(zoned), 331#endif 332#ifdef CONFIG_BTRFS_DEBUG 333 BTRFS_FEAT_ATTR_PTR(extent_tree_v2), 334 BTRFS_FEAT_ATTR_PTR(raid_stripe_tree), 335#endif 336#ifdef CONFIG_FS_VERITY 337 BTRFS_FEAT_ATTR_PTR(verity), 338#endif 339 NULL 340}; 341 342static const struct attribute_group btrfs_feature_attr_group = { 343 .name = "features", 344 .is_visible = btrfs_feature_visible, 345 .attrs = btrfs_supported_feature_attrs, 346}; 347 348static ssize_t rmdir_subvol_show(struct kobject *kobj, 349 struct kobj_attribute *ka, char *buf) 350{ 351 return sysfs_emit(buf, "0\n"); 352} 353BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show); 354 355static ssize_t supported_checksums_show(struct kobject *kobj, 356 struct kobj_attribute *a, char *buf) 357{ 358 ssize_t ret = 0; 359 int i; 360 361 for (i = 0; i < btrfs_get_num_csums(); i++) { 362 /* 363 * This "trick" only works as long as 'enum btrfs_csum_type' has 364 * no holes in it 365 */ 366 ret += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "), 367 btrfs_super_csum_name(i)); 368 369 } 370 371 ret += sysfs_emit_at(buf, ret, "\n"); 372 return ret; 373} 374BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show); 375 376static ssize_t send_stream_version_show(struct kobject *kobj, 377 struct kobj_attribute *ka, char *buf) 378{ 379 return sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION); 380} 381BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show); 382 383static const char *rescue_opts[] = { 384 "usebackuproot", 385 "nologreplay", 386 "ignorebadroots", 387 "ignoredatacsums", 388 "all", 389}; 390 391static ssize_t supported_rescue_options_show(struct kobject *kobj, 392 struct kobj_attribute *a, 393 char *buf) 394{ 395 ssize_t ret = 0; 396 int i; 397 398 for (i = 0; i < ARRAY_SIZE(rescue_opts); i++) 399 ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]); 400 ret += sysfs_emit_at(buf, ret, "\n"); 401 return ret; 402} 403BTRFS_ATTR(static_feature, supported_rescue_options, 404 supported_rescue_options_show); 405 406static ssize_t supported_sectorsizes_show(struct kobject *kobj, 407 struct kobj_attribute *a, 408 char *buf) 409{ 410 ssize_t ret = 0; 411 412 /* An artificial limit to only support 4K and PAGE_SIZE */ 413 if (PAGE_SIZE > SZ_4K) 414 ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K); 415 ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE); 416 417 return ret; 418} 419BTRFS_ATTR(static_feature, supported_sectorsizes, 420 supported_sectorsizes_show); 421 422static ssize_t acl_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) 423{ 424 return sysfs_emit(buf, "%d\n", IS_ENABLED(CONFIG_BTRFS_FS_POSIX_ACL)); 425} 426BTRFS_ATTR(static_feature, acl, acl_show); 427 428static ssize_t temp_fsid_supported_show(struct kobject *kobj, 429 struct kobj_attribute *a, char *buf) 430{ 431 return sysfs_emit(buf, "0\n"); 432} 433BTRFS_ATTR(static_feature, temp_fsid, temp_fsid_supported_show); 434 435/* 436 * Features which only depend on kernel version. 437 * 438 * These are listed in /sys/fs/btrfs/features along with 439 * btrfs_supported_feature_attrs. 440 */ 441static struct attribute *btrfs_supported_static_feature_attrs[] = { 442 BTRFS_ATTR_PTR(static_feature, acl), 443 BTRFS_ATTR_PTR(static_feature, rmdir_subvol), 444 BTRFS_ATTR_PTR(static_feature, supported_checksums), 445 BTRFS_ATTR_PTR(static_feature, send_stream_version), 446 BTRFS_ATTR_PTR(static_feature, supported_rescue_options), 447 BTRFS_ATTR_PTR(static_feature, supported_sectorsizes), 448 BTRFS_ATTR_PTR(static_feature, temp_fsid), 449 NULL 450}; 451 452static const struct attribute_group btrfs_static_feature_attr_group = { 453 .name = "features", 454 .attrs = btrfs_supported_static_feature_attrs, 455}; 456 457/* 458 * Discard statistics and tunables 459 */ 460#define discard_to_fs_info(_kobj) to_fs_info(get_btrfs_kobj(_kobj)) 461 462static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj, 463 struct kobj_attribute *a, 464 char *buf) 465{ 466 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 467 468 return sysfs_emit(buf, "%lld\n", 469 atomic64_read(&fs_info->discard_ctl.discardable_bytes)); 470} 471BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show); 472 473static ssize_t btrfs_discardable_extents_show(struct kobject *kobj, 474 struct kobj_attribute *a, 475 char *buf) 476{ 477 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 478 479 return sysfs_emit(buf, "%d\n", 480 atomic_read(&fs_info->discard_ctl.discardable_extents)); 481} 482BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show); 483 484static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj, 485 struct kobj_attribute *a, 486 char *buf) 487{ 488 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 489 490 return sysfs_emit(buf, "%llu\n", 491 fs_info->discard_ctl.discard_bitmap_bytes); 492} 493BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show); 494 495static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj, 496 struct kobj_attribute *a, 497 char *buf) 498{ 499 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 500 501 return sysfs_emit(buf, "%lld\n", 502 atomic64_read(&fs_info->discard_ctl.discard_bytes_saved)); 503} 504BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show); 505 506static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj, 507 struct kobj_attribute *a, 508 char *buf) 509{ 510 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 511 512 return sysfs_emit(buf, "%llu\n", 513 fs_info->discard_ctl.discard_extent_bytes); 514} 515BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show); 516 517static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj, 518 struct kobj_attribute *a, 519 char *buf) 520{ 521 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 522 523 return sysfs_emit(buf, "%u\n", 524 READ_ONCE(fs_info->discard_ctl.iops_limit)); 525} 526 527static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj, 528 struct kobj_attribute *a, 529 const char *buf, size_t len) 530{ 531 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 532 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 533 u32 iops_limit; 534 int ret; 535 536 ret = kstrtou32(buf, 10, &iops_limit); 537 if (ret) 538 return -EINVAL; 539 540 WRITE_ONCE(discard_ctl->iops_limit, iops_limit); 541 btrfs_discard_calc_delay(discard_ctl); 542 btrfs_discard_schedule_work(discard_ctl, true); 543 return len; 544} 545BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show, 546 btrfs_discard_iops_limit_store); 547 548static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj, 549 struct kobj_attribute *a, 550 char *buf) 551{ 552 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 553 554 return sysfs_emit(buf, "%u\n", 555 READ_ONCE(fs_info->discard_ctl.kbps_limit)); 556} 557 558static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj, 559 struct kobj_attribute *a, 560 const char *buf, size_t len) 561{ 562 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 563 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 564 u32 kbps_limit; 565 int ret; 566 567 ret = kstrtou32(buf, 10, &kbps_limit); 568 if (ret) 569 return -EINVAL; 570 571 WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit); 572 btrfs_discard_schedule_work(discard_ctl, true); 573 return len; 574} 575BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show, 576 btrfs_discard_kbps_limit_store); 577 578static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj, 579 struct kobj_attribute *a, 580 char *buf) 581{ 582 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 583 584 return sysfs_emit(buf, "%llu\n", 585 READ_ONCE(fs_info->discard_ctl.max_discard_size)); 586} 587 588static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj, 589 struct kobj_attribute *a, 590 const char *buf, size_t len) 591{ 592 struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); 593 struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; 594 u64 max_discard_size; 595 int ret; 596 597 ret = kstrtou64(buf, 10, &max_discard_size); 598 if (ret) 599 return -EINVAL; 600 601 WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size); 602 603 return len; 604} 605BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show, 606 btrfs_discard_max_discard_size_store); 607 608/* 609 * Per-filesystem stats for discard (when mounted with discard=async). 610 * 611 * Path: /sys/fs/btrfs/<uuid>/discard/ 612 */ 613static const struct attribute *discard_attrs[] = { 614 BTRFS_ATTR_PTR(discard, discardable_bytes), 615 BTRFS_ATTR_PTR(discard, discardable_extents), 616 BTRFS_ATTR_PTR(discard, discard_bitmap_bytes), 617 BTRFS_ATTR_PTR(discard, discard_bytes_saved), 618 BTRFS_ATTR_PTR(discard, discard_extent_bytes), 619 BTRFS_ATTR_PTR(discard, iops_limit), 620 BTRFS_ATTR_PTR(discard, kbps_limit), 621 BTRFS_ATTR_PTR(discard, max_discard_size), 622 NULL, 623}; 624 625#ifdef CONFIG_BTRFS_DEBUG 626 627/* 628 * Per-filesystem runtime debugging exported via sysfs. 629 * 630 * Path: /sys/fs/btrfs/UUID/debug/ 631 */ 632static const struct attribute *btrfs_debug_mount_attrs[] = { 633 NULL, 634}; 635 636/* 637 * Runtime debugging exported via sysfs, applies to all mounted filesystems. 638 * 639 * Path: /sys/fs/btrfs/debug 640 */ 641static struct attribute *btrfs_debug_feature_attrs[] = { 642 NULL 643}; 644 645static const struct attribute_group btrfs_debug_feature_attr_group = { 646 .name = "debug", 647 .attrs = btrfs_debug_feature_attrs, 648}; 649 650#endif 651 652static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf) 653{ 654 u64 val; 655 if (lock) 656 spin_lock(lock); 657 val = *value_ptr; 658 if (lock) 659 spin_unlock(lock); 660 return sysfs_emit(buf, "%llu\n", val); 661} 662 663static ssize_t global_rsv_size_show(struct kobject *kobj, 664 struct kobj_attribute *ka, char *buf) 665{ 666 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); 667 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 668 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf); 669} 670BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show); 671 672static ssize_t global_rsv_reserved_show(struct kobject *kobj, 673 struct kobj_attribute *a, char *buf) 674{ 675 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); 676 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; 677 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf); 678} 679BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show); 680 681#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj) 682#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj) 683 684static ssize_t raid_bytes_show(struct kobject *kobj, 685 struct kobj_attribute *attr, char *buf); 686BTRFS_ATTR(raid, total_bytes, raid_bytes_show); 687BTRFS_ATTR(raid, used_bytes, raid_bytes_show); 688 689static ssize_t raid_bytes_show(struct kobject *kobj, 690 struct kobj_attribute *attr, char *buf) 691 692{ 693 struct btrfs_space_info *sinfo = to_space_info(kobj->parent); 694 struct btrfs_block_group *block_group; 695 int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags); 696 u64 val = 0; 697 698 down_read(&sinfo->groups_sem); 699 list_for_each_entry(block_group, &sinfo->block_groups[index], list) { 700 if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes)) 701 val += block_group->length; 702 else 703 val += block_group->used; 704 } 705 up_read(&sinfo->groups_sem); 706 return sysfs_emit(buf, "%llu\n", val); 707} 708 709/* 710 * Allocation information about block group profiles. 711 * 712 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/ 713 */ 714static struct attribute *raid_attrs[] = { 715 BTRFS_ATTR_PTR(raid, total_bytes), 716 BTRFS_ATTR_PTR(raid, used_bytes), 717 NULL 718}; 719ATTRIBUTE_GROUPS(raid); 720 721static void release_raid_kobj(struct kobject *kobj) 722{ 723 kfree(to_raid_kobj(kobj)); 724} 725 726static const struct kobj_type btrfs_raid_ktype = { 727 .sysfs_ops = &kobj_sysfs_ops, 728 .release = release_raid_kobj, 729 .default_groups = raid_groups, 730}; 731 732#define SPACE_INFO_ATTR(field) \ 733static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \ 734 struct kobj_attribute *a, \ 735 char *buf) \ 736{ \ 737 struct btrfs_space_info *sinfo = to_space_info(kobj); \ 738 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \ 739} \ 740BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field) 741 742static ssize_t btrfs_chunk_size_show(struct kobject *kobj, 743 struct kobj_attribute *a, char *buf) 744{ 745 struct btrfs_space_info *sinfo = to_space_info(kobj); 746 747 return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size)); 748} 749 750/* 751 * Store new chunk size in space info. Can be called on a read-only filesystem. 752 * 753 * If the new chunk size value is larger than 10% of free space it is reduced 754 * to match that limit. Alignment must be to 256M and the system chunk size 755 * cannot be set. 756 */ 757static ssize_t btrfs_chunk_size_store(struct kobject *kobj, 758 struct kobj_attribute *a, 759 const char *buf, size_t len) 760{ 761 struct btrfs_space_info *space_info = to_space_info(kobj); 762 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj)); 763 char *retptr; 764 u64 val; 765 766 if (!capable(CAP_SYS_ADMIN)) 767 return -EPERM; 768 769 if (!fs_info->fs_devices) 770 return -EINVAL; 771 772 if (btrfs_is_zoned(fs_info)) 773 return -EINVAL; 774 775 /* System block type must not be changed. */ 776 if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM) 777 return -EPERM; 778 779 val = memparse(buf, &retptr); 780 /* There could be trailing '\n', also catch any typos after the value */ 781 retptr = skip_spaces(retptr); 782 if (*retptr != 0 || val == 0) 783 return -EINVAL; 784 785 val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE); 786 787 /* Limit stripe size to 10% of available space. */ 788 val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val); 789 790 /* Must be multiple of 256M. */ 791 val &= ~((u64)SZ_256M - 1); 792 793 /* Must be at least 256M. */ 794 if (val < SZ_256M) 795 return -EINVAL; 796 797 btrfs_update_space_info_chunk_size(space_info, val); 798 799 return len; 800} 801 802static ssize_t btrfs_size_classes_show(struct kobject *kobj, 803 struct kobj_attribute *a, char *buf) 804{ 805 struct btrfs_space_info *sinfo = to_space_info(kobj); 806 struct btrfs_block_group *bg; 807 u32 none = 0; 808 u32 small = 0; 809 u32 medium = 0; 810 u32 large = 0; 811 812 for (int i = 0; i < BTRFS_NR_RAID_TYPES; ++i) { 813 down_read(&sinfo->groups_sem); 814 list_for_each_entry(bg, &sinfo->block_groups[i], list) { 815 if (!btrfs_block_group_should_use_size_class(bg)) 816 continue; 817 switch (bg->size_class) { 818 case BTRFS_BG_SZ_NONE: 819 none++; 820 break; 821 case BTRFS_BG_SZ_SMALL: 822 small++; 823 break; 824 case BTRFS_BG_SZ_MEDIUM: 825 medium++; 826 break; 827 case BTRFS_BG_SZ_LARGE: 828 large++; 829 break; 830 } 831 } 832 up_read(&sinfo->groups_sem); 833 } 834 return sysfs_emit(buf, "none %u\n" 835 "small %u\n" 836 "medium %u\n" 837 "large %u\n", 838 none, small, medium, large); 839} 840 841#ifdef CONFIG_BTRFS_DEBUG 842/* 843 * Request chunk allocation with current chunk size. 844 */ 845static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj, 846 struct kobj_attribute *a, 847 const char *buf, size_t len) 848{ 849 struct btrfs_space_info *space_info = to_space_info(kobj); 850 struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj)); 851 struct btrfs_trans_handle *trans; 852 bool val; 853 int ret; 854 855 if (!capable(CAP_SYS_ADMIN)) 856 return -EPERM; 857 858 if (sb_rdonly(fs_info->sb)) 859 return -EROFS; 860 861 ret = kstrtobool(buf, &val); 862 if (ret) 863 return ret; 864 865 if (!val) 866 return -EINVAL; 867 868 /* 869 * This is unsafe to be called from sysfs context and may cause 870 * unexpected problems. 871 */ 872 trans = btrfs_start_transaction(fs_info->tree_root, 0); 873 if (IS_ERR(trans)) 874 return PTR_ERR(trans); 875 ret = btrfs_force_chunk_alloc(trans, space_info->flags); 876 btrfs_end_transaction(trans); 877 878 if (ret == 1) 879 return len; 880 881 return -ENOSPC; 882} 883BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store); 884 885#endif 886 887SPACE_INFO_ATTR(flags); 888SPACE_INFO_ATTR(total_bytes); 889SPACE_INFO_ATTR(bytes_used); 890SPACE_INFO_ATTR(bytes_pinned); 891SPACE_INFO_ATTR(bytes_reserved); 892SPACE_INFO_ATTR(bytes_may_use); 893SPACE_INFO_ATTR(bytes_readonly); 894SPACE_INFO_ATTR(bytes_zone_unusable); 895SPACE_INFO_ATTR(disk_used); 896SPACE_INFO_ATTR(disk_total); 897BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store); 898BTRFS_ATTR(space_info, size_classes, btrfs_size_classes_show); 899 900static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj, 901 struct kobj_attribute *a, 902 char *buf) 903{ 904 struct btrfs_space_info *space_info = to_space_info(kobj); 905 906 return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->bg_reclaim_threshold)); 907} 908 909static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj, 910 struct kobj_attribute *a, 911 const char *buf, size_t len) 912{ 913 struct btrfs_space_info *space_info = to_space_info(kobj); 914 int thresh; 915 int ret; 916 917 ret = kstrtoint(buf, 10, &thresh); 918 if (ret) 919 return ret; 920 921 if (thresh < 0 || thresh > 100) 922 return -EINVAL; 923 924 WRITE_ONCE(space_info->bg_reclaim_threshold, thresh); 925 926 return len; 927} 928 929BTRFS_ATTR_RW(space_info, bg_reclaim_threshold, 930 btrfs_sinfo_bg_reclaim_threshold_show, 931 btrfs_sinfo_bg_reclaim_threshold_store); 932 933/* 934 * Allocation information about block group types. 935 * 936 * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/ 937 */ 938static struct attribute *space_info_attrs[] = { 939 BTRFS_ATTR_PTR(space_info, flags), 940 BTRFS_ATTR_PTR(space_info, total_bytes), 941 BTRFS_ATTR_PTR(space_info, bytes_used), 942 BTRFS_ATTR_PTR(space_info, bytes_pinned), 943 BTRFS_ATTR_PTR(space_info, bytes_reserved), 944 BTRFS_ATTR_PTR(space_info, bytes_may_use), 945 BTRFS_ATTR_PTR(space_info, bytes_readonly), 946 BTRFS_ATTR_PTR(space_info, bytes_zone_unusable), 947 BTRFS_ATTR_PTR(space_info, disk_used), 948 BTRFS_ATTR_PTR(space_info, disk_total), 949 BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold), 950 BTRFS_ATTR_PTR(space_info, chunk_size), 951 BTRFS_ATTR_PTR(space_info, size_classes), 952#ifdef CONFIG_BTRFS_DEBUG 953 BTRFS_ATTR_PTR(space_info, force_chunk_alloc), 954#endif 955 NULL, 956}; 957ATTRIBUTE_GROUPS(space_info); 958 959static void space_info_release(struct kobject *kobj) 960{ 961 struct btrfs_space_info *sinfo = to_space_info(kobj); 962 kfree(sinfo); 963} 964 965static const struct kobj_type space_info_ktype = { 966 .sysfs_ops = &kobj_sysfs_ops, 967 .release = space_info_release, 968 .default_groups = space_info_groups, 969}; 970 971/* 972 * Allocation information about block groups. 973 * 974 * Path: /sys/fs/btrfs/<uuid>/allocation/ 975 */ 976static const struct attribute *allocation_attrs[] = { 977 BTRFS_ATTR_PTR(allocation, global_rsv_reserved), 978 BTRFS_ATTR_PTR(allocation, global_rsv_size), 979 NULL, 980}; 981 982static ssize_t btrfs_label_show(struct kobject *kobj, 983 struct kobj_attribute *a, char *buf) 984{ 985 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 986 char *label = fs_info->super_copy->label; 987 ssize_t ret; 988 989 spin_lock(&fs_info->super_lock); 990 ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label); 991 spin_unlock(&fs_info->super_lock); 992 993 return ret; 994} 995 996static ssize_t btrfs_label_store(struct kobject *kobj, 997 struct kobj_attribute *a, 998 const char *buf, size_t len) 999{ 1000 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1001 size_t p_len; 1002 1003 if (!fs_info) 1004 return -EPERM; 1005 1006 if (sb_rdonly(fs_info->sb)) 1007 return -EROFS; 1008 1009 /* 1010 * p_len is the len until the first occurrence of either 1011 * '\n' or '\0' 1012 */ 1013 p_len = strcspn(buf, "\n"); 1014 1015 if (p_len >= BTRFS_LABEL_SIZE) 1016 return -EINVAL; 1017 1018 spin_lock(&fs_info->super_lock); 1019 memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE); 1020 memcpy(fs_info->super_copy->label, buf, p_len); 1021 spin_unlock(&fs_info->super_lock); 1022 1023 /* 1024 * We don't want to do full transaction commit from inside sysfs 1025 */ 1026 set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags); 1027 wake_up_process(fs_info->transaction_kthread); 1028 1029 return len; 1030} 1031BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store); 1032 1033static ssize_t btrfs_nodesize_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->nodesize); 1039} 1040 1041BTRFS_ATTR(, nodesize, btrfs_nodesize_show); 1042 1043static ssize_t btrfs_sectorsize_show(struct kobject *kobj, 1044 struct kobj_attribute *a, char *buf) 1045{ 1046 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1047 1048 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); 1049} 1050 1051BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show); 1052 1053static ssize_t btrfs_commit_stats_show(struct kobject *kobj, 1054 struct kobj_attribute *a, char *buf) 1055{ 1056 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1057 1058 return sysfs_emit(buf, 1059 "commits %llu\n" 1060 "last_commit_ms %llu\n" 1061 "max_commit_ms %llu\n" 1062 "total_commit_ms %llu\n", 1063 fs_info->commit_stats.commit_count, 1064 div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC), 1065 div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC), 1066 div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC)); 1067} 1068 1069static ssize_t btrfs_commit_stats_store(struct kobject *kobj, 1070 struct kobj_attribute *a, 1071 const char *buf, size_t len) 1072{ 1073 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1074 unsigned long val; 1075 int ret; 1076 1077 if (!fs_info) 1078 return -EPERM; 1079 1080 if (!capable(CAP_SYS_RESOURCE)) 1081 return -EPERM; 1082 1083 ret = kstrtoul(buf, 10, &val); 1084 if (ret) 1085 return ret; 1086 if (val) 1087 return -EINVAL; 1088 1089 WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0); 1090 1091 return len; 1092} 1093BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store); 1094 1095static ssize_t btrfs_clone_alignment_show(struct kobject *kobj, 1096 struct kobj_attribute *a, char *buf) 1097{ 1098 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1099 1100 return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); 1101} 1102 1103BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show); 1104 1105static ssize_t quota_override_show(struct kobject *kobj, 1106 struct kobj_attribute *a, char *buf) 1107{ 1108 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1109 int quota_override; 1110 1111 quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 1112 return sysfs_emit(buf, "%d\n", quota_override); 1113} 1114 1115static ssize_t quota_override_store(struct kobject *kobj, 1116 struct kobj_attribute *a, 1117 const char *buf, size_t len) 1118{ 1119 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1120 unsigned long knob; 1121 int err; 1122 1123 if (!fs_info) 1124 return -EPERM; 1125 1126 if (!capable(CAP_SYS_RESOURCE)) 1127 return -EPERM; 1128 1129 err = kstrtoul(buf, 10, &knob); 1130 if (err) 1131 return err; 1132 if (knob > 1) 1133 return -EINVAL; 1134 1135 if (knob) 1136 set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 1137 else 1138 clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); 1139 1140 return len; 1141} 1142 1143BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store); 1144 1145static ssize_t btrfs_metadata_uuid_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, "%pU\n", fs_info->fs_devices->metadata_uuid); 1151} 1152 1153BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show); 1154 1155static ssize_t btrfs_checksum_show(struct kobject *kobj, 1156 struct kobj_attribute *a, char *buf) 1157{ 1158 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1159 u16 csum_type = btrfs_super_csum_type(fs_info->super_copy); 1160 1161 return sysfs_emit(buf, "%s (%s)\n", 1162 btrfs_super_csum_name(csum_type), 1163 crypto_shash_driver_name(fs_info->csum_shash)); 1164} 1165 1166BTRFS_ATTR(, checksum, btrfs_checksum_show); 1167 1168static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj, 1169 struct kobj_attribute *a, char *buf) 1170{ 1171 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1172 const char *str; 1173 1174 switch (READ_ONCE(fs_info->exclusive_operation)) { 1175 case BTRFS_EXCLOP_NONE: 1176 str = "none\n"; 1177 break; 1178 case BTRFS_EXCLOP_BALANCE: 1179 str = "balance\n"; 1180 break; 1181 case BTRFS_EXCLOP_BALANCE_PAUSED: 1182 str = "balance paused\n"; 1183 break; 1184 case BTRFS_EXCLOP_DEV_ADD: 1185 str = "device add\n"; 1186 break; 1187 case BTRFS_EXCLOP_DEV_REMOVE: 1188 str = "device remove\n"; 1189 break; 1190 case BTRFS_EXCLOP_DEV_REPLACE: 1191 str = "device replace\n"; 1192 break; 1193 case BTRFS_EXCLOP_RESIZE: 1194 str = "resize\n"; 1195 break; 1196 case BTRFS_EXCLOP_SWAP_ACTIVATE: 1197 str = "swap activate\n"; 1198 break; 1199 default: 1200 str = "UNKNOWN\n"; 1201 break; 1202 } 1203 return sysfs_emit(buf, "%s", str); 1204} 1205BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show); 1206 1207static ssize_t btrfs_generation_show(struct kobject *kobj, 1208 struct kobj_attribute *a, char *buf) 1209{ 1210 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1211 1212 return sysfs_emit(buf, "%llu\n", btrfs_get_fs_generation(fs_info)); 1213} 1214BTRFS_ATTR(, generation, btrfs_generation_show); 1215 1216static ssize_t btrfs_temp_fsid_show(struct kobject *kobj, 1217 struct kobj_attribute *a, char *buf) 1218{ 1219 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1220 1221 return sysfs_emit(buf, "%d\n", fs_info->fs_devices->temp_fsid); 1222} 1223BTRFS_ATTR(, temp_fsid, btrfs_temp_fsid_show); 1224 1225static const char * const btrfs_read_policy_name[] = { "pid" }; 1226 1227static ssize_t btrfs_read_policy_show(struct kobject *kobj, 1228 struct kobj_attribute *a, char *buf) 1229{ 1230 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); 1231 const enum btrfs_read_policy policy = READ_ONCE(fs_devices->read_policy); 1232 ssize_t ret = 0; 1233 int i; 1234 1235 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) { 1236 if (policy == i) 1237 ret += sysfs_emit_at(buf, ret, "%s[%s]", 1238 (ret == 0 ? "" : " "), 1239 btrfs_read_policy_name[i]); 1240 else 1241 ret += sysfs_emit_at(buf, ret, "%s%s", 1242 (ret == 0 ? "" : " "), 1243 btrfs_read_policy_name[i]); 1244 } 1245 1246 ret += sysfs_emit_at(buf, ret, "\n"); 1247 1248 return ret; 1249} 1250 1251static ssize_t btrfs_read_policy_store(struct kobject *kobj, 1252 struct kobj_attribute *a, 1253 const char *buf, size_t len) 1254{ 1255 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); 1256 int i; 1257 1258 for (i = 0; i < BTRFS_NR_READ_POLICY; i++) { 1259 if (sysfs_streq(buf, btrfs_read_policy_name[i])) { 1260 if (i != READ_ONCE(fs_devices->read_policy)) { 1261 WRITE_ONCE(fs_devices->read_policy, i); 1262 btrfs_info(fs_devices->fs_info, 1263 "read policy set to '%s'", 1264 btrfs_read_policy_name[i]); 1265 } 1266 return len; 1267 } 1268 } 1269 1270 return -EINVAL; 1271} 1272BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store); 1273 1274static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj, 1275 struct kobj_attribute *a, 1276 char *buf) 1277{ 1278 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1279 1280 return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold)); 1281} 1282 1283static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj, 1284 struct kobj_attribute *a, 1285 const char *buf, size_t len) 1286{ 1287 struct btrfs_fs_info *fs_info = to_fs_info(kobj); 1288 int thresh; 1289 int ret; 1290 1291 ret = kstrtoint(buf, 10, &thresh); 1292 if (ret) 1293 return ret; 1294 1295#ifdef CONFIG_BTRFS_DEBUG 1296 if (thresh != 0 && (thresh > 100)) 1297 return -EINVAL; 1298#else 1299 if (thresh != 0 && (thresh <= 50 || thresh > 100)) 1300 return -EINVAL; 1301#endif 1302 1303 WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh); 1304 1305 return len; 1306} 1307BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show, 1308 btrfs_bg_reclaim_threshold_store); 1309 1310#ifdef CONFIG_BTRFS_DEBUG 1311static ssize_t btrfs_offload_csum_show(struct kobject *kobj, 1312 struct kobj_attribute *a, char *buf) 1313{ 1314 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); 1315 1316 switch (READ_ONCE(fs_devices->offload_csum_mode)) { 1317 case BTRFS_OFFLOAD_CSUM_AUTO: 1318 return sysfs_emit(buf, "auto\n"); 1319 case BTRFS_OFFLOAD_CSUM_FORCE_ON: 1320 return sysfs_emit(buf, "1\n"); 1321 case BTRFS_OFFLOAD_CSUM_FORCE_OFF: 1322 return sysfs_emit(buf, "0\n"); 1323 default: 1324 WARN_ON(1); 1325 return -EINVAL; 1326 } 1327} 1328 1329static ssize_t btrfs_offload_csum_store(struct kobject *kobj, 1330 struct kobj_attribute *a, const char *buf, 1331 size_t len) 1332{ 1333 struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); 1334 int ret; 1335 bool val; 1336 1337 ret = kstrtobool(buf, &val); 1338 if (ret == 0) 1339 WRITE_ONCE(fs_devices->offload_csum_mode, 1340 val ? BTRFS_OFFLOAD_CSUM_FORCE_ON : BTRFS_OFFLOAD_CSUM_FORCE_OFF); 1341 else if (ret == -EINVAL && sysfs_streq(buf, "auto")) 1342 WRITE_ONCE(fs_devices->offload_csum_mode, BTRFS_OFFLOAD_CSUM_AUTO); 1343 else 1344 return -EINVAL; 1345 1346 return len; 1347} 1348BTRFS_ATTR_RW(, offload_csum, btrfs_offload_csum_show, btrfs_offload_csum_store); 1349#endif 1350 1351/* 1352 * Per-filesystem information and stats. 1353 * 1354 * Path: /sys/fs/btrfs/<uuid>/ 1355 */ 1356static const struct attribute *btrfs_attrs[] = { 1357 BTRFS_ATTR_PTR(, label), 1358 BTRFS_ATTR_PTR(, nodesize), 1359 BTRFS_ATTR_PTR(, sectorsize), 1360 BTRFS_ATTR_PTR(, clone_alignment), 1361 BTRFS_ATTR_PTR(, quota_override), 1362 BTRFS_ATTR_PTR(, metadata_uuid), 1363 BTRFS_ATTR_PTR(, checksum), 1364 BTRFS_ATTR_PTR(, exclusive_operation), 1365 BTRFS_ATTR_PTR(, generation), 1366 BTRFS_ATTR_PTR(, read_policy), 1367 BTRFS_ATTR_PTR(, bg_reclaim_threshold), 1368 BTRFS_ATTR_PTR(, commit_stats), 1369 BTRFS_ATTR_PTR(, temp_fsid), 1370#ifdef CONFIG_BTRFS_DEBUG 1371 BTRFS_ATTR_PTR(, offload_csum), 1372#endif 1373 NULL, 1374}; 1375 1376static void btrfs_release_fsid_kobj(struct kobject *kobj) 1377{ 1378 struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj); 1379 1380 memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject)); 1381 complete(&fs_devs->kobj_unregister); 1382} 1383 1384static const struct kobj_type btrfs_ktype = { 1385 .sysfs_ops = &kobj_sysfs_ops, 1386 .release = btrfs_release_fsid_kobj, 1387}; 1388 1389static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj) 1390{ 1391 if (kobj->ktype != &btrfs_ktype) 1392 return NULL; 1393 return container_of(kobj, struct btrfs_fs_devices, fsid_kobj); 1394} 1395 1396static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj) 1397{ 1398 if (kobj->ktype != &btrfs_ktype) 1399 return NULL; 1400 return to_fs_devs(kobj)->fs_info; 1401} 1402 1403static struct kobject *get_btrfs_kobj(struct kobject *kobj) 1404{ 1405 while (kobj) { 1406 if (kobj->ktype == &btrfs_ktype) 1407 return kobj; 1408 kobj = kobj->parent; 1409 } 1410 return NULL; 1411} 1412 1413#define NUM_FEATURE_BITS 64 1414#define BTRFS_FEATURE_NAME_MAX 13 1415static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX]; 1416static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS]; 1417 1418static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) == 1419 ARRAY_SIZE(btrfs_feature_attrs)); 1420static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) == 1421 ARRAY_SIZE(btrfs_feature_attrs[0])); 1422 1423static const u64 supported_feature_masks[FEAT_MAX] = { 1424 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP, 1425 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP, 1426 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP, 1427}; 1428 1429static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add) 1430{ 1431 int set; 1432 1433 for (set = 0; set < FEAT_MAX; set++) { 1434 int i; 1435 struct attribute *attrs[2]; 1436 struct attribute_group agroup = { 1437 .name = "features", 1438 .attrs = attrs, 1439 }; 1440 u64 features = get_features(fs_info, set); 1441 features &= ~supported_feature_masks[set]; 1442 1443 if (!features) 1444 continue; 1445 1446 attrs[1] = NULL; 1447 for (i = 0; i < NUM_FEATURE_BITS; i++) { 1448 struct btrfs_feature_attr *fa; 1449 1450 if (!(features & (1ULL << i))) 1451 continue; 1452 1453 fa = &btrfs_feature_attrs[set][i]; 1454 attrs[0] = &fa->kobj_attr.attr; 1455 if (add) { 1456 int ret; 1457 ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj, 1458 &agroup); 1459 if (ret) 1460 return ret; 1461 } else 1462 sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj, 1463 &agroup); 1464 } 1465 1466 } 1467 return 0; 1468} 1469 1470static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) 1471{ 1472 if (fs_devs->devinfo_kobj) { 1473 kobject_del(fs_devs->devinfo_kobj); 1474 kobject_put(fs_devs->devinfo_kobj); 1475 fs_devs->devinfo_kobj = NULL; 1476 } 1477 1478 if (fs_devs->devices_kobj) { 1479 kobject_del(fs_devs->devices_kobj); 1480 kobject_put(fs_devs->devices_kobj); 1481 fs_devs->devices_kobj = NULL; 1482 } 1483 1484 if (fs_devs->fsid_kobj.state_initialized) { 1485 kobject_del(&fs_devs->fsid_kobj); 1486 kobject_put(&fs_devs->fsid_kobj); 1487 wait_for_completion(&fs_devs->kobj_unregister); 1488 } 1489} 1490 1491/* when fs_devs is NULL it will remove all fsid kobject */ 1492void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) 1493{ 1494 struct list_head *fs_uuids = btrfs_get_fs_uuids(); 1495 1496 if (fs_devs) { 1497 __btrfs_sysfs_remove_fsid(fs_devs); 1498 return; 1499 } 1500 1501 list_for_each_entry(fs_devs, fs_uuids, fs_list) { 1502 __btrfs_sysfs_remove_fsid(fs_devs); 1503 } 1504} 1505 1506static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices) 1507{ 1508 struct btrfs_device *device; 1509 struct btrfs_fs_devices *seed; 1510 1511 list_for_each_entry(device, &fs_devices->devices, dev_list) 1512 btrfs_sysfs_remove_device(device); 1513 1514 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { 1515 list_for_each_entry(device, &seed->devices, dev_list) 1516 btrfs_sysfs_remove_device(device); 1517 } 1518} 1519 1520void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info) 1521{ 1522 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; 1523 1524 sysfs_remove_link(fsid_kobj, "bdi"); 1525 1526 if (fs_info->space_info_kobj) { 1527 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); 1528 kobject_del(fs_info->space_info_kobj); 1529 kobject_put(fs_info->space_info_kobj); 1530 } 1531 if (fs_info->discard_kobj) { 1532 sysfs_remove_files(fs_info->discard_kobj, discard_attrs); 1533 kobject_del(fs_info->discard_kobj); 1534 kobject_put(fs_info->discard_kobj); 1535 } 1536#ifdef CONFIG_BTRFS_DEBUG 1537 if (fs_info->debug_kobj) { 1538 sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); 1539 kobject_del(fs_info->debug_kobj); 1540 kobject_put(fs_info->debug_kobj); 1541 } 1542#endif 1543 addrm_unknown_feature_attrs(fs_info, false); 1544 sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group); 1545 sysfs_remove_files(fsid_kobj, btrfs_attrs); 1546 btrfs_sysfs_remove_fs_devices(fs_info->fs_devices); 1547} 1548 1549static const char * const btrfs_feature_set_names[FEAT_MAX] = { 1550 [FEAT_COMPAT] = "compat", 1551 [FEAT_COMPAT_RO] = "compat_ro", 1552 [FEAT_INCOMPAT] = "incompat", 1553}; 1554 1555const char *btrfs_feature_set_name(enum btrfs_feature_set set) 1556{ 1557 return btrfs_feature_set_names[set]; 1558} 1559 1560char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags) 1561{ 1562 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */ 1563 int len = 0; 1564 int i; 1565 char *str; 1566 1567 str = kmalloc(bufsize, GFP_KERNEL); 1568 if (!str) 1569 return str; 1570 1571 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 1572 const char *name; 1573 1574 if (!(flags & (1ULL << i))) 1575 continue; 1576 1577 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name; 1578 len += scnprintf(str + len, bufsize - len, "%s%s", 1579 len ? "," : "", name); 1580 } 1581 1582 return str; 1583} 1584 1585static void init_feature_attrs(void) 1586{ 1587 struct btrfs_feature_attr *fa; 1588 int set, i; 1589 1590 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs)); 1591 memset(btrfs_unknown_feature_names, 0, 1592 sizeof(btrfs_unknown_feature_names)); 1593 1594 for (i = 0; btrfs_supported_feature_attrs[i]; i++) { 1595 struct btrfs_feature_attr *sfa; 1596 struct attribute *a = btrfs_supported_feature_attrs[i]; 1597 int bit; 1598 sfa = attr_to_btrfs_feature_attr(a); 1599 bit = ilog2(sfa->feature_bit); 1600 fa = &btrfs_feature_attrs[sfa->feature_set][bit]; 1601 1602 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name; 1603 } 1604 1605 for (set = 0; set < FEAT_MAX; set++) { 1606 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { 1607 char *name = btrfs_unknown_feature_names[set][i]; 1608 fa = &btrfs_feature_attrs[set][i]; 1609 1610 if (fa->kobj_attr.attr.name) 1611 continue; 1612 1613 snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u", 1614 btrfs_feature_set_names[set], i); 1615 1616 fa->kobj_attr.attr.name = name; 1617 fa->kobj_attr.attr.mode = S_IRUGO; 1618 fa->feature_set = set; 1619 fa->feature_bit = 1ULL << i; 1620 } 1621 } 1622} 1623 1624/* 1625 * Create a sysfs entry for a given block group type at path 1626 * /sys/fs/btrfs/UUID/allocation/data/TYPE 1627 */ 1628void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache) 1629{ 1630 struct btrfs_fs_info *fs_info = cache->fs_info; 1631 struct btrfs_space_info *space_info = cache->space_info; 1632 struct raid_kobject *rkobj; 1633 const int index = btrfs_bg_flags_to_raid_index(cache->flags); 1634 unsigned int nofs_flag; 1635 int ret; 1636 1637 /* 1638 * Setup a NOFS context because kobject_add(), deep in its call chain, 1639 * does GFP_KERNEL allocations, and we are often called in a context 1640 * where if reclaim is triggered we can deadlock (we are either holding 1641 * a transaction handle or some lock required for a transaction 1642 * commit). 1643 */ 1644 nofs_flag = memalloc_nofs_save(); 1645 1646 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS); 1647 if (!rkobj) { 1648 memalloc_nofs_restore(nofs_flag); 1649 btrfs_warn(cache->fs_info, 1650 "couldn't alloc memory for raid level kobject"); 1651 return; 1652 } 1653 1654 rkobj->flags = cache->flags; 1655 kobject_init(&rkobj->kobj, &btrfs_raid_ktype); 1656 1657 /* 1658 * We call this either on mount, or if we've created a block group for a 1659 * new index type while running (i.e. when restriping). The running 1660 * case is tricky because we could race with other threads, so we need 1661 * to have this check to make sure we didn't already init the kobject. 1662 * 1663 * We don't have to protect on the free side because it only happens on 1664 * unmount. 1665 */ 1666 spin_lock(&space_info->lock); 1667 if (space_info->block_group_kobjs[index]) { 1668 spin_unlock(&space_info->lock); 1669 kobject_put(&rkobj->kobj); 1670 return; 1671 } else { 1672 space_info->block_group_kobjs[index] = &rkobj->kobj; 1673 } 1674 spin_unlock(&space_info->lock); 1675 1676 ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s", 1677 btrfs_bg_type_to_raid_name(rkobj->flags)); 1678 memalloc_nofs_restore(nofs_flag); 1679 if (ret) { 1680 spin_lock(&space_info->lock); 1681 space_info->block_group_kobjs[index] = NULL; 1682 spin_unlock(&space_info->lock); 1683 kobject_put(&rkobj->kobj); 1684 btrfs_warn(fs_info, 1685 "failed to add kobject for block cache, ignoring"); 1686 return; 1687 } 1688} 1689 1690/* 1691 * Remove sysfs directories for all block group types of a given space info and 1692 * the space info as well 1693 */ 1694void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info) 1695{ 1696 int i; 1697 1698 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { 1699 struct kobject *kobj; 1700 1701 kobj = space_info->block_group_kobjs[i]; 1702 space_info->block_group_kobjs[i] = NULL; 1703 if (kobj) { 1704 kobject_del(kobj); 1705 kobject_put(kobj); 1706 } 1707 } 1708 kobject_del(&space_info->kobj); 1709 kobject_put(&space_info->kobj); 1710} 1711 1712static const char *alloc_name(u64 flags) 1713{ 1714 switch (flags) { 1715 case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA: 1716 return "mixed"; 1717 case BTRFS_BLOCK_GROUP_METADATA: 1718 return "metadata"; 1719 case BTRFS_BLOCK_GROUP_DATA: 1720 return "data"; 1721 case BTRFS_BLOCK_GROUP_SYSTEM: 1722 return "system"; 1723 default: 1724 WARN_ON(1); 1725 return "invalid-combination"; 1726 } 1727} 1728 1729/* 1730 * Create a sysfs entry for a space info type at path 1731 * /sys/fs/btrfs/UUID/allocation/TYPE 1732 */ 1733int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info, 1734 struct btrfs_space_info *space_info) 1735{ 1736 int ret; 1737 1738 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype, 1739 fs_info->space_info_kobj, "%s", 1740 alloc_name(space_info->flags)); 1741 if (ret) { 1742 kobject_put(&space_info->kobj); 1743 return ret; 1744 } 1745 1746 return 0; 1747} 1748 1749void btrfs_sysfs_remove_device(struct btrfs_device *device) 1750{ 1751 struct kobject *devices_kobj; 1752 1753 /* 1754 * Seed fs_devices devices_kobj aren't used, fetch kobject from the 1755 * fs_info::fs_devices. 1756 */ 1757 devices_kobj = device->fs_info->fs_devices->devices_kobj; 1758 ASSERT(devices_kobj); 1759 1760 if (device->bdev) 1761 sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name); 1762 1763 if (device->devid_kobj.state_initialized) { 1764 kobject_del(&device->devid_kobj); 1765 kobject_put(&device->devid_kobj); 1766 wait_for_completion(&device->kobj_unregister); 1767 } 1768} 1769 1770static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj, 1771 struct kobj_attribute *a, 1772 char *buf) 1773{ 1774 int val; 1775 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1776 devid_kobj); 1777 1778 val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 1779 1780 return sysfs_emit(buf, "%d\n", val); 1781} 1782BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show); 1783 1784static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj, 1785 struct kobj_attribute *a, char *buf) 1786{ 1787 int val; 1788 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1789 devid_kobj); 1790 1791 val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); 1792 1793 return sysfs_emit(buf, "%d\n", val); 1794} 1795BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show); 1796 1797static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj, 1798 struct kobj_attribute *a, 1799 char *buf) 1800{ 1801 int val; 1802 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1803 devid_kobj); 1804 1805 val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 1806 1807 return sysfs_emit(buf, "%d\n", val); 1808} 1809BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show); 1810 1811static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj, 1812 struct kobj_attribute *a, 1813 char *buf) 1814{ 1815 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1816 devid_kobj); 1817 1818 return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max)); 1819} 1820 1821static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj, 1822 struct kobj_attribute *a, 1823 const char *buf, size_t len) 1824{ 1825 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1826 devid_kobj); 1827 char *endptr; 1828 unsigned long long limit; 1829 1830 limit = memparse(buf, &endptr); 1831 /* There could be trailing '\n', also catch any typos after the value. */ 1832 endptr = skip_spaces(endptr); 1833 if (*endptr != 0) 1834 return -EINVAL; 1835 WRITE_ONCE(device->scrub_speed_max, limit); 1836 return len; 1837} 1838BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show, 1839 btrfs_devinfo_scrub_speed_max_store); 1840 1841static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj, 1842 struct kobj_attribute *a, char *buf) 1843{ 1844 int val; 1845 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1846 devid_kobj); 1847 1848 val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 1849 1850 return sysfs_emit(buf, "%d\n", val); 1851} 1852BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show); 1853 1854static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj, 1855 struct kobj_attribute *a, char *buf) 1856{ 1857 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1858 devid_kobj); 1859 1860 return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid); 1861} 1862BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show); 1863 1864static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj, 1865 struct kobj_attribute *a, char *buf) 1866{ 1867 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1868 devid_kobj); 1869 1870 if (!device->dev_stats_valid) 1871 return sysfs_emit(buf, "invalid\n"); 1872 1873 /* 1874 * Print all at once so we get a snapshot of all values from the same 1875 * time. Keep them in sync and in order of definition of 1876 * btrfs_dev_stat_values. 1877 */ 1878 return sysfs_emit(buf, 1879 "write_errs %d\n" 1880 "read_errs %d\n" 1881 "flush_errs %d\n" 1882 "corruption_errs %d\n" 1883 "generation_errs %d\n", 1884 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS), 1885 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS), 1886 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS), 1887 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS), 1888 btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS)); 1889} 1890BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show); 1891 1892/* 1893 * Information about one device. 1894 * 1895 * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/ 1896 */ 1897static struct attribute *devid_attrs[] = { 1898 BTRFS_ATTR_PTR(devid, error_stats), 1899 BTRFS_ATTR_PTR(devid, fsid), 1900 BTRFS_ATTR_PTR(devid, in_fs_metadata), 1901 BTRFS_ATTR_PTR(devid, missing), 1902 BTRFS_ATTR_PTR(devid, replace_target), 1903 BTRFS_ATTR_PTR(devid, scrub_speed_max), 1904 BTRFS_ATTR_PTR(devid, writeable), 1905 NULL 1906}; 1907ATTRIBUTE_GROUPS(devid); 1908 1909static void btrfs_release_devid_kobj(struct kobject *kobj) 1910{ 1911 struct btrfs_device *device = container_of(kobj, struct btrfs_device, 1912 devid_kobj); 1913 1914 memset(&device->devid_kobj, 0, sizeof(struct kobject)); 1915 complete(&device->kobj_unregister); 1916} 1917 1918static const struct kobj_type devid_ktype = { 1919 .sysfs_ops = &kobj_sysfs_ops, 1920 .default_groups = devid_groups, 1921 .release = btrfs_release_devid_kobj, 1922}; 1923 1924int btrfs_sysfs_add_device(struct btrfs_device *device) 1925{ 1926 int ret; 1927 unsigned int nofs_flag; 1928 struct kobject *devices_kobj; 1929 struct kobject *devinfo_kobj; 1930 1931 /* 1932 * Make sure we use the fs_info::fs_devices to fetch the kobjects even 1933 * for the seed fs_devices 1934 */ 1935 devices_kobj = device->fs_info->fs_devices->devices_kobj; 1936 devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj; 1937 ASSERT(devices_kobj); 1938 ASSERT(devinfo_kobj); 1939 1940 nofs_flag = memalloc_nofs_save(); 1941 1942 if (device->bdev) { 1943 struct kobject *disk_kobj = bdev_kobj(device->bdev); 1944 1945 ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name); 1946 if (ret) { 1947 btrfs_warn(device->fs_info, 1948 "creating sysfs device link for devid %llu failed: %d", 1949 device->devid, ret); 1950 goto out; 1951 } 1952 } 1953 1954 init_completion(&device->kobj_unregister); 1955 ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype, 1956 devinfo_kobj, "%llu", device->devid); 1957 if (ret) { 1958 kobject_put(&device->devid_kobj); 1959 btrfs_warn(device->fs_info, 1960 "devinfo init for devid %llu failed: %d", 1961 device->devid, ret); 1962 } 1963 1964out: 1965 memalloc_nofs_restore(nofs_flag); 1966 return ret; 1967} 1968 1969static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices) 1970{ 1971 int ret; 1972 struct btrfs_device *device; 1973 struct btrfs_fs_devices *seed; 1974 1975 list_for_each_entry(device, &fs_devices->devices, dev_list) { 1976 ret = btrfs_sysfs_add_device(device); 1977 if (ret) 1978 goto fail; 1979 } 1980 1981 list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { 1982 list_for_each_entry(device, &seed->devices, dev_list) { 1983 ret = btrfs_sysfs_add_device(device); 1984 if (ret) 1985 goto fail; 1986 } 1987 } 1988 1989 return 0; 1990 1991fail: 1992 btrfs_sysfs_remove_fs_devices(fs_devices); 1993 return ret; 1994} 1995 1996void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action) 1997{ 1998 int ret; 1999 2000 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 2001 if (ret) 2002 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n", 2003 action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 2004 &disk_to_dev(bdev->bd_disk)->kobj); 2005} 2006 2007void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices) 2008 2009{ 2010 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE]; 2011 2012 /* 2013 * Sprouting changes fsid of the mounted filesystem, rename the fsid 2014 * directory 2015 */ 2016 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid); 2017 if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf)) 2018 btrfs_warn(fs_devices->fs_info, 2019 "sysfs: failed to create fsid for sprout"); 2020} 2021 2022void btrfs_sysfs_update_devid(struct btrfs_device *device) 2023{ 2024 char tmp[24]; 2025 2026 snprintf(tmp, sizeof(tmp), "%llu", device->devid); 2027 2028 if (kobject_rename(&device->devid_kobj, tmp)) 2029 btrfs_warn(device->fs_devices->fs_info, 2030 "sysfs: failed to update devid for %llu", 2031 device->devid); 2032} 2033 2034/* /sys/fs/btrfs/ entry */ 2035static struct kset *btrfs_kset; 2036 2037/* 2038 * Creates: 2039 * /sys/fs/btrfs/UUID 2040 * 2041 * Can be called by the device discovery thread. 2042 */ 2043int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs) 2044{ 2045 int error; 2046 2047 init_completion(&fs_devs->kobj_unregister); 2048 fs_devs->fsid_kobj.kset = btrfs_kset; 2049 error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL, 2050 "%pU", fs_devs->fsid); 2051 if (error) { 2052 kobject_put(&fs_devs->fsid_kobj); 2053 return error; 2054 } 2055 2056 fs_devs->devices_kobj = kobject_create_and_add("devices", 2057 &fs_devs->fsid_kobj); 2058 if (!fs_devs->devices_kobj) { 2059 btrfs_err(fs_devs->fs_info, 2060 "failed to init sysfs device interface"); 2061 btrfs_sysfs_remove_fsid(fs_devs); 2062 return -ENOMEM; 2063 } 2064 2065 fs_devs->devinfo_kobj = kobject_create_and_add("devinfo", 2066 &fs_devs->fsid_kobj); 2067 if (!fs_devs->devinfo_kobj) { 2068 btrfs_err(fs_devs->fs_info, 2069 "failed to init sysfs devinfo kobject"); 2070 btrfs_sysfs_remove_fsid(fs_devs); 2071 return -ENOMEM; 2072 } 2073 2074 return 0; 2075} 2076 2077int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info) 2078{ 2079 int error; 2080 struct btrfs_fs_devices *fs_devs = fs_info->fs_devices; 2081 struct kobject *fsid_kobj = &fs_devs->fsid_kobj; 2082 2083 error = btrfs_sysfs_add_fs_devices(fs_devs); 2084 if (error) 2085 return error; 2086 2087 error = sysfs_create_files(fsid_kobj, btrfs_attrs); 2088 if (error) { 2089 btrfs_sysfs_remove_fs_devices(fs_devs); 2090 return error; 2091 } 2092 2093 error = sysfs_create_group(fsid_kobj, 2094 &btrfs_feature_attr_group); 2095 if (error) 2096 goto failure; 2097 2098#ifdef CONFIG_BTRFS_DEBUG 2099 fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj); 2100 if (!fs_info->debug_kobj) { 2101 error = -ENOMEM; 2102 goto failure; 2103 } 2104 2105 error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); 2106 if (error) 2107 goto failure; 2108#endif 2109 2110 /* Discard directory */ 2111 fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj); 2112 if (!fs_info->discard_kobj) { 2113 error = -ENOMEM; 2114 goto failure; 2115 } 2116 2117 error = sysfs_create_files(fs_info->discard_kobj, discard_attrs); 2118 if (error) 2119 goto failure; 2120 2121 error = addrm_unknown_feature_attrs(fs_info, true); 2122 if (error) 2123 goto failure; 2124 2125 error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi"); 2126 if (error) 2127 goto failure; 2128 2129 fs_info->space_info_kobj = kobject_create_and_add("allocation", 2130 fsid_kobj); 2131 if (!fs_info->space_info_kobj) { 2132 error = -ENOMEM; 2133 goto failure; 2134 } 2135 2136 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs); 2137 if (error) 2138 goto failure; 2139 2140 return 0; 2141failure: 2142 btrfs_sysfs_remove_mounted(fs_info); 2143 return error; 2144} 2145 2146static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj, 2147 struct kobj_attribute *a, 2148 char *buf) 2149{ 2150 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2151 bool enabled; 2152 2153 spin_lock(&fs_info->qgroup_lock); 2154 enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON; 2155 spin_unlock(&fs_info->qgroup_lock); 2156 2157 return sysfs_emit(buf, "%d\n", enabled); 2158} 2159BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show); 2160 2161static ssize_t qgroup_mode_show(struct kobject *qgroups_kobj, 2162 struct kobj_attribute *a, 2163 char *buf) 2164{ 2165 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2166 ssize_t ret = 0; 2167 2168 spin_lock(&fs_info->qgroup_lock); 2169 ASSERT(btrfs_qgroup_enabled(fs_info)); 2170 switch (btrfs_qgroup_mode(fs_info)) { 2171 case BTRFS_QGROUP_MODE_FULL: 2172 ret = sysfs_emit(buf, "qgroup\n"); 2173 break; 2174 case BTRFS_QGROUP_MODE_SIMPLE: 2175 ret = sysfs_emit(buf, "squota\n"); 2176 break; 2177 default: 2178 btrfs_warn(fs_info, "unexpected qgroup mode %d\n", 2179 btrfs_qgroup_mode(fs_info)); 2180 break; 2181 } 2182 spin_unlock(&fs_info->qgroup_lock); 2183 2184 return ret; 2185} 2186BTRFS_ATTR(qgroups, mode, qgroup_mode_show); 2187 2188static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj, 2189 struct kobj_attribute *a, 2190 char *buf) 2191{ 2192 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2193 bool inconsistent; 2194 2195 spin_lock(&fs_info->qgroup_lock); 2196 inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT); 2197 spin_unlock(&fs_info->qgroup_lock); 2198 2199 return sysfs_emit(buf, "%d\n", inconsistent); 2200} 2201BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show); 2202 2203static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj, 2204 struct kobj_attribute *a, 2205 char *buf) 2206{ 2207 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2208 u8 result; 2209 2210 spin_lock(&fs_info->qgroup_lock); 2211 result = fs_info->qgroup_drop_subtree_thres; 2212 spin_unlock(&fs_info->qgroup_lock); 2213 2214 return sysfs_emit(buf, "%d\n", result); 2215} 2216 2217static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj, 2218 struct kobj_attribute *a, 2219 const char *buf, size_t len) 2220{ 2221 struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent); 2222 u8 new_thres; 2223 int ret; 2224 2225 ret = kstrtou8(buf, 10, &new_thres); 2226 if (ret) 2227 return -EINVAL; 2228 2229 if (new_thres > BTRFS_MAX_LEVEL) 2230 return -EINVAL; 2231 2232 spin_lock(&fs_info->qgroup_lock); 2233 fs_info->qgroup_drop_subtree_thres = new_thres; 2234 spin_unlock(&fs_info->qgroup_lock); 2235 2236 return len; 2237} 2238BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show, 2239 qgroup_drop_subtree_thres_store); 2240 2241/* 2242 * Qgroups global info 2243 * 2244 * Path: /sys/fs/btrfs/<uuid>/qgroups/ 2245 */ 2246static struct attribute *qgroups_attrs[] = { 2247 BTRFS_ATTR_PTR(qgroups, enabled), 2248 BTRFS_ATTR_PTR(qgroups, inconsistent), 2249 BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold), 2250 BTRFS_ATTR_PTR(qgroups, mode), 2251 NULL 2252}; 2253ATTRIBUTE_GROUPS(qgroups); 2254 2255static void qgroups_release(struct kobject *kobj) 2256{ 2257 kfree(kobj); 2258} 2259 2260static const struct kobj_type qgroups_ktype = { 2261 .sysfs_ops = &kobj_sysfs_ops, 2262 .default_groups = qgroups_groups, 2263 .release = qgroups_release, 2264}; 2265 2266static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj) 2267{ 2268 return to_fs_info(kobj->parent->parent); 2269} 2270 2271#define QGROUP_ATTR(_member, _show_name) \ 2272static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \ 2273 struct kobj_attribute *a, \ 2274 char *buf) \ 2275{ \ 2276 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ 2277 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ 2278 struct btrfs_qgroup, kobj); \ 2279 return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \ 2280} \ 2281BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member) 2282 2283#define QGROUP_RSV_ATTR(_name, _type) \ 2284static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \ 2285 struct kobj_attribute *a, \ 2286 char *buf) \ 2287{ \ 2288 struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ 2289 struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ 2290 struct btrfs_qgroup, kobj); \ 2291 return btrfs_show_u64(&qgroup->rsv.values[_type], \ 2292 &fs_info->qgroup_lock, buf); \ 2293} \ 2294BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name) 2295 2296QGROUP_ATTR(rfer, referenced); 2297QGROUP_ATTR(excl, exclusive); 2298QGROUP_ATTR(max_rfer, max_referenced); 2299QGROUP_ATTR(max_excl, max_exclusive); 2300QGROUP_ATTR(lim_flags, limit_flags); 2301QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA); 2302QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS); 2303QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC); 2304 2305/* 2306 * Qgroup information. 2307 * 2308 * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/ 2309 */ 2310static struct attribute *qgroup_attrs[] = { 2311 BTRFS_ATTR_PTR(qgroup, referenced), 2312 BTRFS_ATTR_PTR(qgroup, exclusive), 2313 BTRFS_ATTR_PTR(qgroup, max_referenced), 2314 BTRFS_ATTR_PTR(qgroup, max_exclusive), 2315 BTRFS_ATTR_PTR(qgroup, limit_flags), 2316 BTRFS_ATTR_PTR(qgroup, rsv_data), 2317 BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans), 2318 BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc), 2319 NULL 2320}; 2321ATTRIBUTE_GROUPS(qgroup); 2322 2323static void qgroup_release(struct kobject *kobj) 2324{ 2325 struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj); 2326 2327 memset(&qgroup->kobj, 0, sizeof(*kobj)); 2328} 2329 2330static const struct kobj_type qgroup_ktype = { 2331 .sysfs_ops = &kobj_sysfs_ops, 2332 .release = qgroup_release, 2333 .default_groups = qgroup_groups, 2334}; 2335 2336int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info, 2337 struct btrfs_qgroup *qgroup) 2338{ 2339 struct kobject *qgroups_kobj = fs_info->qgroups_kobj; 2340 int ret; 2341 2342 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2343 return 0; 2344 if (qgroup->kobj.state_initialized) 2345 return 0; 2346 if (!qgroups_kobj) 2347 return -EINVAL; 2348 2349 ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj, 2350 "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid), 2351 btrfs_qgroup_subvolid(qgroup->qgroupid)); 2352 if (ret < 0) 2353 kobject_put(&qgroup->kobj); 2354 2355 return ret; 2356} 2357 2358void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info) 2359{ 2360 struct btrfs_qgroup *qgroup; 2361 struct btrfs_qgroup *next; 2362 2363 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2364 return; 2365 2366 rbtree_postorder_for_each_entry_safe(qgroup, next, 2367 &fs_info->qgroup_tree, node) 2368 btrfs_sysfs_del_one_qgroup(fs_info, qgroup); 2369 if (fs_info->qgroups_kobj) { 2370 kobject_del(fs_info->qgroups_kobj); 2371 kobject_put(fs_info->qgroups_kobj); 2372 fs_info->qgroups_kobj = NULL; 2373 } 2374} 2375 2376/* Called when qgroups get initialized, thus there is no need for locking */ 2377int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info) 2378{ 2379 struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; 2380 struct btrfs_qgroup *qgroup; 2381 struct btrfs_qgroup *next; 2382 int ret = 0; 2383 2384 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2385 return 0; 2386 2387 ASSERT(fsid_kobj); 2388 if (fs_info->qgroups_kobj) 2389 return 0; 2390 2391 fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL); 2392 if (!fs_info->qgroups_kobj) 2393 return -ENOMEM; 2394 2395 ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype, 2396 fsid_kobj, "qgroups"); 2397 if (ret < 0) 2398 goto out; 2399 2400 rbtree_postorder_for_each_entry_safe(qgroup, next, 2401 &fs_info->qgroup_tree, node) { 2402 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); 2403 if (ret < 0) 2404 goto out; 2405 } 2406 2407out: 2408 if (ret < 0) 2409 btrfs_sysfs_del_qgroups(fs_info); 2410 return ret; 2411} 2412 2413void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info, 2414 struct btrfs_qgroup *qgroup) 2415{ 2416 if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) 2417 return; 2418 2419 if (qgroup->kobj.state_initialized) { 2420 kobject_del(&qgroup->kobj); 2421 kobject_put(&qgroup->kobj); 2422 } 2423} 2424 2425/* 2426 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current 2427 * values in superblock. Call after any changes to incompat/compat_ro flags 2428 */ 2429void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info) 2430{ 2431 struct kobject *fsid_kobj; 2432 int ret; 2433 2434 if (!fs_info) 2435 return; 2436 2437 fsid_kobj = &fs_info->fs_devices->fsid_kobj; 2438 if (!fsid_kobj->state_initialized) 2439 return; 2440 2441 ret = sysfs_update_group(fsid_kobj, &btrfs_feature_attr_group); 2442 if (ret < 0) 2443 btrfs_warn(fs_info, 2444 "failed to update /sys/fs/btrfs/%pU/features: %d", 2445 fs_info->fs_devices->fsid, ret); 2446} 2447 2448int __init btrfs_init_sysfs(void) 2449{ 2450 int ret; 2451 2452 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); 2453 if (!btrfs_kset) 2454 return -ENOMEM; 2455 2456 init_feature_attrs(); 2457 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2458 if (ret) 2459 goto out2; 2460 ret = sysfs_merge_group(&btrfs_kset->kobj, 2461 &btrfs_static_feature_attr_group); 2462 if (ret) 2463 goto out_remove_group; 2464 2465#ifdef CONFIG_BTRFS_DEBUG 2466 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); 2467 if (ret) { 2468 sysfs_unmerge_group(&btrfs_kset->kobj, 2469 &btrfs_static_feature_attr_group); 2470 goto out_remove_group; 2471 } 2472#endif 2473 2474 return 0; 2475 2476out_remove_group: 2477 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2478out2: 2479 kset_unregister(btrfs_kset); 2480 2481 return ret; 2482} 2483 2484void __cold btrfs_exit_sysfs(void) 2485{ 2486 sysfs_unmerge_group(&btrfs_kset->kobj, 2487 &btrfs_static_feature_attr_group); 2488 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); 2489#ifdef CONFIG_BTRFS_DEBUG 2490 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); 2491#endif 2492 kset_unregister(btrfs_kset); 2493} 2494