1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #ifndef BTRFS_VOLUMES_H 7 #define BTRFS_VOLUMES_H 8 9 #include <linux/sort.h> 10 #include <linux/btrfs.h> 11 #include "async-thread.h" 12 #include "messages.h" 13 #include "tree-checker.h" 14 #include "rcu-string.h" 15 16 #define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G) 17 18 extern struct mutex uuid_mutex; 19 20 #define BTRFS_STRIPE_LEN SZ_64K 21 22 /* Used by sanity check for btrfs_raid_types. */ 23 #define const_ffs(n) (__builtin_ctzll(n) + 1) 24 25 /* 26 * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires 27 * RAID0 always to be the lowest profile bit. 28 * Although it's part of on-disk format and should never change, do extra 29 * compile-time sanity checks. 30 */ 31 static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) < 32 const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0)); 33 static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) > 34 ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK)); 35 36 /* ilog2() can handle both constants and variables */ 37 #define BTRFS_BG_FLAG_TO_INDEX(profile) \ 38 ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1)) 39 40 enum btrfs_raid_types { 41 /* SINGLE is the special one as it doesn't have on-disk bit. */ 42 BTRFS_RAID_SINGLE = 0, 43 44 BTRFS_RAID_RAID0 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0), 45 BTRFS_RAID_RAID1 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1), 46 BTRFS_RAID_DUP = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP), 47 BTRFS_RAID_RAID10 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10), 48 BTRFS_RAID_RAID5 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5), 49 BTRFS_RAID_RAID6 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6), 50 BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3), 51 BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4), 52 53 BTRFS_NR_RAID_TYPES 54 }; 55 56 /* 57 * Use sequence counter to get consistent device stat data on 58 * 32-bit processors. 59 */ 60 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 61 #include <linux/seqlock.h> 62 #define __BTRFS_NEED_DEVICE_DATA_ORDERED 63 #define btrfs_device_data_ordered_init(device) \ 64 seqcount_init(&device->data_seqcount) 65 #else 66 #define btrfs_device_data_ordered_init(device) do { } while (0) 67 #endif 68 69 #define BTRFS_DEV_STATE_WRITEABLE (0) 70 #define BTRFS_DEV_STATE_IN_FS_METADATA (1) 71 #define BTRFS_DEV_STATE_MISSING (2) 72 #define BTRFS_DEV_STATE_REPLACE_TGT (3) 73 #define BTRFS_DEV_STATE_FLUSH_SENT (4) 74 #define BTRFS_DEV_STATE_NO_READA (5) 75 76 struct btrfs_zoned_device_info; 77 78 struct btrfs_device { 79 struct list_head dev_list; /* device_list_mutex */ 80 struct list_head dev_alloc_list; /* chunk mutex */ 81 struct list_head post_commit_list; /* chunk mutex */ 82 struct btrfs_fs_devices *fs_devices; 83 struct btrfs_fs_info *fs_info; 84 85 struct rcu_string __rcu *name; 86 87 u64 generation; 88 89 struct block_device *bdev; 90 91 struct btrfs_zoned_device_info *zone_info; 92 93 /* the mode sent to blkdev_get */ 94 fmode_t mode; 95 96 /* 97 * Device's major-minor number. Must be set even if the device is not 98 * opened (bdev == NULL), unless the device is missing. 99 */ 100 dev_t devt; 101 unsigned long dev_state; 102 blk_status_t last_flush_error; 103 104 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED 105 seqcount_t data_seqcount; 106 #endif 107 108 /* the internal btrfs device id */ 109 u64 devid; 110 111 /* size of the device in memory */ 112 u64 total_bytes; 113 114 /* size of the device on disk */ 115 u64 disk_total_bytes; 116 117 /* bytes used */ 118 u64 bytes_used; 119 120 /* optimal io alignment for this device */ 121 u32 io_align; 122 123 /* optimal io width for this device */ 124 u32 io_width; 125 /* type and info about this device */ 126 u64 type; 127 128 /* minimal io size for this device */ 129 u32 sector_size; 130 131 /* physical drive uuid (or lvm uuid) */ 132 u8 uuid[BTRFS_UUID_SIZE]; 133 134 /* 135 * size of the device on the current transaction 136 * 137 * This variant is update when committing the transaction, 138 * and protected by chunk mutex 139 */ 140 u64 commit_total_bytes; 141 142 /* bytes used on the current transaction */ 143 u64 commit_bytes_used; 144 145 /* Bio used for flushing device barriers */ 146 struct bio flush_bio; 147 struct completion flush_wait; 148 149 /* per-device scrub information */ 150 struct scrub_ctx *scrub_ctx; 151 152 /* disk I/O failure stats. For detailed description refer to 153 * enum btrfs_dev_stat_values in ioctl.h */ 154 int dev_stats_valid; 155 156 /* Counter to record the change of device stats */ 157 atomic_t dev_stats_ccnt; 158 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX]; 159 160 struct extent_io_tree alloc_state; 161 162 struct completion kobj_unregister; 163 /* For sysfs/FSID/devinfo/devid/ */ 164 struct kobject devid_kobj; 165 166 /* Bandwidth limit for scrub, in bytes */ 167 u64 scrub_speed_max; 168 }; 169 170 /* 171 * Block group or device which contains an active swapfile. Used for preventing 172 * unsafe operations while a swapfile is active. 173 * 174 * These are sorted on (ptr, inode) (note that a block group or device can 175 * contain more than one swapfile). We compare the pointer values because we 176 * don't actually care what the object is, we just need a quick check whether 177 * the object exists in the rbtree. 178 */ 179 struct btrfs_swapfile_pin { 180 struct rb_node node; 181 void *ptr; 182 struct inode *inode; 183 /* 184 * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr 185 * points to a struct btrfs_device. 186 */ 187 bool is_block_group; 188 /* 189 * Only used when 'is_block_group' is true and it is the number of 190 * extents used by a swapfile for this block group ('ptr' field). 191 */ 192 int bg_extent_count; 193 }; 194 195 /* 196 * If we read those variants at the context of their own lock, we needn't 197 * use the following helpers, reading them directly is safe. 198 */ 199 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 200 #define BTRFS_DEVICE_GETSET_FUNCS(name) \ 201 static inline u64 \ 202 btrfs_device_get_##name(const struct btrfs_device *dev) \ 203 { \ 204 u64 size; \ 205 unsigned int seq; \ 206 \ 207 do { \ 208 seq = read_seqcount_begin(&dev->data_seqcount); \ 209 size = dev->name; \ 210 } while (read_seqcount_retry(&dev->data_seqcount, seq)); \ 211 return size; \ 212 } \ 213 \ 214 static inline void \ 215 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \ 216 { \ 217 preempt_disable(); \ 218 write_seqcount_begin(&dev->data_seqcount); \ 219 dev->name = size; \ 220 write_seqcount_end(&dev->data_seqcount); \ 221 preempt_enable(); \ 222 } 223 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION) 224 #define BTRFS_DEVICE_GETSET_FUNCS(name) \ 225 static inline u64 \ 226 btrfs_device_get_##name(const struct btrfs_device *dev) \ 227 { \ 228 u64 size; \ 229 \ 230 preempt_disable(); \ 231 size = dev->name; \ 232 preempt_enable(); \ 233 return size; \ 234 } \ 235 \ 236 static inline void \ 237 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \ 238 { \ 239 preempt_disable(); \ 240 dev->name = size; \ 241 preempt_enable(); \ 242 } 243 #else 244 #define BTRFS_DEVICE_GETSET_FUNCS(name) \ 245 static inline u64 \ 246 btrfs_device_get_##name(const struct btrfs_device *dev) \ 247 { \ 248 return dev->name; \ 249 } \ 250 \ 251 static inline void \ 252 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \ 253 { \ 254 dev->name = size; \ 255 } 256 #endif 257 258 BTRFS_DEVICE_GETSET_FUNCS(total_bytes); 259 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes); 260 BTRFS_DEVICE_GETSET_FUNCS(bytes_used); 261 262 enum btrfs_chunk_allocation_policy { 263 BTRFS_CHUNK_ALLOC_REGULAR, 264 BTRFS_CHUNK_ALLOC_ZONED, 265 }; 266 267 /* 268 * Read policies for mirrored block group profiles, read picks the stripe based 269 * on these policies. 270 */ 271 enum btrfs_read_policy { 272 /* Use process PID to choose the stripe */ 273 BTRFS_READ_POLICY_PID, 274 BTRFS_NR_READ_POLICY, 275 }; 276 277 struct btrfs_fs_devices { 278 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */ 279 u8 metadata_uuid[BTRFS_FSID_SIZE]; 280 bool fsid_change; 281 struct list_head fs_list; 282 283 /* 284 * Number of devices under this fsid including missing and 285 * replace-target device and excludes seed devices. 286 */ 287 u64 num_devices; 288 289 /* 290 * The number of devices that successfully opened, including 291 * replace-target, excludes seed devices. 292 */ 293 u64 open_devices; 294 295 /* The number of devices that are under the chunk allocation list. */ 296 u64 rw_devices; 297 298 /* Count of missing devices under this fsid excluding seed device. */ 299 u64 missing_devices; 300 u64 total_rw_bytes; 301 302 /* 303 * Count of devices from btrfs_super_block::num_devices for this fsid, 304 * which includes the seed device, excludes the transient replace-target 305 * device. 306 */ 307 u64 total_devices; 308 309 /* Highest generation number of seen devices */ 310 u64 latest_generation; 311 312 /* 313 * The mount device or a device with highest generation after removal 314 * or replace. 315 */ 316 struct btrfs_device *latest_dev; 317 318 /* all of the devices in the FS, protected by a mutex 319 * so we can safely walk it to write out the supers without 320 * worrying about add/remove by the multi-device code. 321 * Scrubbing super can kick off supers writing by holding 322 * this mutex lock. 323 */ 324 struct mutex device_list_mutex; 325 326 /* List of all devices, protected by device_list_mutex */ 327 struct list_head devices; 328 329 /* 330 * Devices which can satisfy space allocation. Protected by 331 * chunk_mutex 332 */ 333 struct list_head alloc_list; 334 335 struct list_head seed_list; 336 bool seeding; 337 338 int opened; 339 340 /* set when we find or add a device that doesn't have the 341 * nonrot flag set 342 */ 343 bool rotating; 344 /* Devices support TRIM/discard commands */ 345 bool discardable; 346 347 struct btrfs_fs_info *fs_info; 348 /* sysfs kobjects */ 349 struct kobject fsid_kobj; 350 struct kobject *devices_kobj; 351 struct kobject *devinfo_kobj; 352 struct completion kobj_unregister; 353 354 enum btrfs_chunk_allocation_policy chunk_alloc_policy; 355 356 /* Policy used to read the mirrored stripes */ 357 enum btrfs_read_policy read_policy; 358 }; 359 360 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \ 361 - sizeof(struct btrfs_chunk)) \ 362 / sizeof(struct btrfs_stripe) + 1) 363 364 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \ 365 - 2 * sizeof(struct btrfs_disk_key) \ 366 - 2 * sizeof(struct btrfs_chunk)) \ 367 / sizeof(struct btrfs_stripe) + 1) 368 369 struct btrfs_io_stripe { 370 struct btrfs_device *dev; 371 union { 372 /* Block mapping */ 373 u64 physical; 374 /* For the endio handler */ 375 struct btrfs_io_context *bioc; 376 }; 377 }; 378 379 struct btrfs_discard_stripe { 380 struct btrfs_device *dev; 381 u64 physical; 382 u64 length; 383 }; 384 385 /* 386 * Context for IO subsmission for device stripe. 387 * 388 * - Track the unfinished mirrors for mirror based profiles 389 * Mirror based profiles are SINGLE/DUP/RAID1/RAID10. 390 * 391 * - Contain the logical -> physical mapping info 392 * Used by submit_stripe_bio() for mapping logical bio 393 * into physical device address. 394 * 395 * - Contain device replace info 396 * Used by handle_ops_on_dev_replace() to copy logical bios 397 * into the new device. 398 * 399 * - Contain RAID56 full stripe logical bytenrs 400 */ 401 struct btrfs_io_context { 402 refcount_t refs; 403 struct btrfs_fs_info *fs_info; 404 u64 map_type; /* get from map_lookup->type */ 405 struct bio *orig_bio; 406 atomic_t error; 407 int max_errors; 408 int num_stripes; 409 int mirror_num; 410 int num_tgtdevs; 411 int *tgtdev_map; 412 /* 413 * logical block numbers for the start of each stripe 414 * The last one or two are p/q. These are sorted, 415 * so raid_map[0] is the start of our full stripe 416 */ 417 u64 *raid_map; 418 struct btrfs_io_stripe stripes[]; 419 }; 420 421 struct btrfs_device_info { 422 struct btrfs_device *dev; 423 u64 dev_offset; 424 u64 max_avail; 425 u64 total_avail; 426 }; 427 428 struct btrfs_raid_attr { 429 u8 sub_stripes; /* sub_stripes info for map */ 430 u8 dev_stripes; /* stripes per dev */ 431 u8 devs_max; /* max devs to use */ 432 u8 devs_min; /* min devs needed */ 433 u8 tolerated_failures; /* max tolerated fail devs */ 434 u8 devs_increment; /* ndevs has to be a multiple of this */ 435 u8 ncopies; /* how many copies to data has */ 436 u8 nparity; /* number of stripes worth of bytes to store 437 * parity information */ 438 u8 mindev_error; /* error code if min devs requisite is unmet */ 439 const char raid_name[8]; /* name of the raid */ 440 u64 bg_flag; /* block group flag of the raid */ 441 }; 442 443 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES]; 444 445 struct map_lookup { 446 u64 type; 447 int io_align; 448 int io_width; 449 u32 stripe_len; 450 int num_stripes; 451 int sub_stripes; 452 int verified_stripes; /* For mount time dev extent verification */ 453 struct btrfs_io_stripe stripes[]; 454 }; 455 456 #define map_lookup_size(n) (sizeof(struct map_lookup) + \ 457 (sizeof(struct btrfs_io_stripe) * (n))) 458 459 struct btrfs_balance_args; 460 struct btrfs_balance_progress; 461 struct btrfs_balance_control { 462 struct btrfs_balance_args data; 463 struct btrfs_balance_args meta; 464 struct btrfs_balance_args sys; 465 466 u64 flags; 467 468 struct btrfs_balance_progress stat; 469 }; 470 471 /* 472 * Search for a given device by the set parameters 473 */ 474 struct btrfs_dev_lookup_args { 475 u64 devid; 476 u8 *uuid; 477 u8 *fsid; 478 bool missing; 479 }; 480 481 /* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */ 482 #define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 } 483 484 #define BTRFS_DEV_LOOKUP_ARGS(name) \ 485 struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT 486 487 enum btrfs_map_op { 488 BTRFS_MAP_READ, 489 BTRFS_MAP_WRITE, 490 BTRFS_MAP_DISCARD, 491 BTRFS_MAP_GET_READ_MIRRORS, 492 }; 493 494 static inline enum btrfs_map_op btrfs_op(struct bio *bio) 495 { 496 switch (bio_op(bio)) { 497 case REQ_OP_DISCARD: 498 return BTRFS_MAP_DISCARD; 499 case REQ_OP_WRITE: 500 case REQ_OP_ZONE_APPEND: 501 return BTRFS_MAP_WRITE; 502 default: 503 WARN_ON_ONCE(1); 504 fallthrough; 505 case REQ_OP_READ: 506 return BTRFS_MAP_READ; 507 } 508 } 509 510 static inline unsigned long btrfs_chunk_item_size(int num_stripes) 511 { 512 ASSERT(num_stripes); 513 return sizeof(struct btrfs_chunk) + 514 sizeof(struct btrfs_stripe) * (num_stripes - 1); 515 } 516 517 void btrfs_get_bioc(struct btrfs_io_context *bioc); 518 void btrfs_put_bioc(struct btrfs_io_context *bioc); 519 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 520 u64 logical, u64 *length, 521 struct btrfs_io_context **bioc_ret, int mirror_num); 522 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 523 u64 logical, u64 *length, 524 struct btrfs_io_context **bioc_ret); 525 int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 526 u64 logical, u64 *length, 527 struct btrfs_io_context **bioc_ret, 528 struct btrfs_io_stripe *smap, int *mirror_num_ret, 529 int need_raid_map); 530 struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info, 531 u64 logical, u64 *length_ret, 532 u32 *num_stripes); 533 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info); 534 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info); 535 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans, 536 u64 type); 537 void btrfs_mapping_tree_free(struct extent_map_tree *tree); 538 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 539 fmode_t flags, void *holder); 540 struct btrfs_device *btrfs_scan_one_device(const char *path, 541 fmode_t flags, void *holder); 542 int btrfs_forget_devices(dev_t devt); 543 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices); 544 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices); 545 void btrfs_assign_next_active_device(struct btrfs_device *device, 546 struct btrfs_device *this_dev); 547 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, 548 u64 devid, 549 const char *devpath); 550 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info, 551 struct btrfs_dev_lookup_args *args, 552 const char *path); 553 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, 554 const u64 *devid, const u8 *uuid, 555 const char *path); 556 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args); 557 void btrfs_free_device(struct btrfs_device *device); 558 int btrfs_rm_device(struct btrfs_fs_info *fs_info, 559 struct btrfs_dev_lookup_args *args, 560 struct block_device **bdev, fmode_t *mode); 561 void __exit btrfs_cleanup_fs_uuids(void); 562 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len); 563 int btrfs_grow_device(struct btrfs_trans_handle *trans, 564 struct btrfs_device *device, u64 new_size); 565 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices, 566 const struct btrfs_dev_lookup_args *args); 567 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size); 568 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path); 569 int btrfs_balance(struct btrfs_fs_info *fs_info, 570 struct btrfs_balance_control *bctl, 571 struct btrfs_ioctl_balance_args *bargs); 572 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf); 573 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info); 574 int btrfs_recover_balance(struct btrfs_fs_info *fs_info); 575 int btrfs_pause_balance(struct btrfs_fs_info *fs_info); 576 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset); 577 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info); 578 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info); 579 int btrfs_uuid_scan_kthread(void *data); 580 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset); 581 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, 582 u64 *start, u64 *max_avail); 583 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index); 584 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info, 585 struct btrfs_ioctl_get_dev_stats *stats); 586 int btrfs_init_devices_late(struct btrfs_fs_info *fs_info); 587 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info); 588 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans); 589 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev); 590 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev); 591 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev); 592 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info, 593 u64 logical, u64 len); 594 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info, 595 u64 logical); 596 u64 btrfs_calc_stripe_length(const struct extent_map *em); 597 int btrfs_nr_parity_stripes(u64 type); 598 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans, 599 struct btrfs_block_group *bg); 600 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset); 601 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info, 602 u64 logical, u64 length); 603 void btrfs_release_disk_super(struct btrfs_super_block *super); 604 605 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev, 606 int index) 607 { 608 atomic_inc(dev->dev_stat_values + index); 609 /* 610 * This memory barrier orders stores updating statistics before stores 611 * updating dev_stats_ccnt. 612 * 613 * It pairs with smp_rmb() in btrfs_run_dev_stats(). 614 */ 615 smp_mb__before_atomic(); 616 atomic_inc(&dev->dev_stats_ccnt); 617 } 618 619 static inline int btrfs_dev_stat_read(struct btrfs_device *dev, 620 int index) 621 { 622 return atomic_read(dev->dev_stat_values + index); 623 } 624 625 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev, 626 int index) 627 { 628 int ret; 629 630 ret = atomic_xchg(dev->dev_stat_values + index, 0); 631 /* 632 * atomic_xchg implies a full memory barriers as per atomic_t.txt: 633 * - RMW operations that have a return value are fully ordered; 634 * 635 * This implicit memory barriers is paired with the smp_rmb in 636 * btrfs_run_dev_stats 637 */ 638 atomic_inc(&dev->dev_stats_ccnt); 639 return ret; 640 } 641 642 static inline void btrfs_dev_stat_set(struct btrfs_device *dev, 643 int index, unsigned long val) 644 { 645 atomic_set(dev->dev_stat_values + index, val); 646 /* 647 * This memory barrier orders stores updating statistics before stores 648 * updating dev_stats_ccnt. 649 * 650 * It pairs with smp_rmb() in btrfs_run_dev_stats(). 651 */ 652 smp_mb__before_atomic(); 653 atomic_inc(&dev->dev_stats_ccnt); 654 } 655 656 static inline const char *btrfs_dev_name(const struct btrfs_device *device) 657 { 658 if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) 659 return "<missing disk>"; 660 else 661 return rcu_str_deref(device->name); 662 } 663 664 void btrfs_commit_device_sizes(struct btrfs_transaction *trans); 665 666 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void); 667 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info, 668 struct btrfs_device *failing_dev); 669 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, 670 struct block_device *bdev, 671 const char *device_path); 672 673 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags); 674 int btrfs_bg_type_to_factor(u64 flags); 675 const char *btrfs_bg_type_to_raid_name(u64 flags); 676 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info); 677 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical); 678 679 bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr); 680 681 #endif 682