fs/btrfs/volumes.h

   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/bio.h>
  10 #include <linux/sort.h>
  11 #include <linux/btrfs.h>
  12 #include "async-thread.h"
  13
  14 #define BTRFS_MAX_DATA_CHUNK_SIZE       (10ULL * SZ_1G)
  15
  16 extern struct mutex uuid_mutex;
  17
  18 #define BTRFS_STRIPE_LEN        SZ_64K
  19
  20 struct btrfs_io_geometry {
  21         /* remaining bytes before crossing a stripe */
  22         u64 len;
  23         /* offset of logical address in chunk */
  24         u64 offset;
  25         /* length of single IO stripe */
  26         u64 stripe_len;
  27         /* number of stripe where address falls */
  28         u64 stripe_nr;
  29         /* offset of address in stripe */
  30         u64 stripe_offset;
  31         /* offset of raid56 stripe into the chunk */
  32         u64 raid56_stripe_offset;
  33 };
  34
  35 /*
  36  * Use sequence counter to get consistent device stat data on
  37  * 32-bit processors.
  38  */
  39 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  40 #include <linux/seqlock.h>
  41 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
  42 #define btrfs_device_data_ordered_init(device)  \
  43         seqcount_init(&device->data_seqcount)
  44 #else
  45 #define btrfs_device_data_ordered_init(device) do { } while (0)
  46 #endif
  47
  48 #define BTRFS_DEV_STATE_WRITEABLE       (0)
  49 #define BTRFS_DEV_STATE_IN_FS_METADATA  (1)
  50 #define BTRFS_DEV_STATE_MISSING         (2)
  51 #define BTRFS_DEV_STATE_REPLACE_TGT     (3)
  52 #define BTRFS_DEV_STATE_FLUSH_SENT      (4)
  53 #define BTRFS_DEV_STATE_NO_READA        (5)
  54
  55 struct btrfs_zoned_device_info;
  56
  57 struct btrfs_device {
  58         struct list_head dev_list; /* device_list_mutex */
  59         struct list_head dev_alloc_list; /* chunk mutex */
  60         struct list_head post_commit_list; /* chunk mutex */
  61         struct btrfs_fs_devices *fs_devices;
  62         struct btrfs_fs_info *fs_info;
  63
  64         struct rcu_string __rcu *name;
  65
  66         u64 generation;
  67
  68         struct block_device *bdev;
  69
  70         struct btrfs_zoned_device_info *zone_info;
  71
  72         /* the mode sent to blkdev_get */
  73         fmode_t mode;
  74
  75         unsigned long dev_state;
  76         blk_status_t last_flush_error;
  77
  78 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
  79         seqcount_t data_seqcount;
  80 #endif
  81
  82         /* the internal btrfs device id */
  83         u64 devid;
  84
  85         /* size of the device in memory */
  86         u64 total_bytes;
  87
  88         /* size of the device on disk */
  89         u64 disk_total_bytes;
  90
  91         /* bytes used */
  92         u64 bytes_used;
  93
  94         /* optimal io alignment for this device */
  95         u32 io_align;
  96
  97         /* optimal io width for this device */
  98         u32 io_width;
  99         /* type and info about this device */
 100         u64 type;
 101
 102         /* minimal io size for this device */
 103         u32 sector_size;
 104
 105         /* physical drive uuid (or lvm uuid) */
 106         u8 uuid[BTRFS_UUID_SIZE];
 107
 108         /*
 109          * size of the device on the current transaction
 110          *
 111          * This variant is update when committing the transaction,
 112          * and protected by chunk mutex
 113          */
 114         u64 commit_total_bytes;
 115
 116         /* bytes used on the current transaction */
 117         u64 commit_bytes_used;
 118
 119         /* for sending down flush barriers */
 120         struct bio *flush_bio;
 121         struct completion flush_wait;
 122
 123         /* per-device scrub information */
 124         struct scrub_ctx *scrub_ctx;
 125
 126         /* readahead state */
 127         atomic_t reada_in_flight;
 128         u64 reada_next;
 129         struct reada_zone *reada_curr_zone;
 130         struct radix_tree_root reada_zones;
 131         struct radix_tree_root reada_extents;
 132
 133         /* disk I/O failure stats. For detailed description refer to
 134          * enum btrfs_dev_stat_values in ioctl.h */
 135         int dev_stats_valid;
 136
 137         /* Counter to record the change of device stats */
 138         atomic_t dev_stats_ccnt;
 139         atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
 140
 141         struct extent_io_tree alloc_state;
 142
 143         struct completion kobj_unregister;
 144         /* For sysfs/FSID/devinfo/devid/ */
 145         struct kobject devid_kobj;
 146 };
 147
 148 /*
 149  * If we read those variants at the context of their own lock, we needn't
 150  * use the following helpers, reading them directly is safe.
 151  */
 152 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 153 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 154 static inline u64                                                       \
 155 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 156 {                                                                       \
 157         u64 size;                                                       \
 158         unsigned int seq;                                               \
 159                                                                         \
 160         do {                                                            \
 161                 seq = read_seqcount_begin(&dev->data_seqcount);         \
 162                 size = dev->name;                                       \
 163         } while (read_seqcount_retry(&dev->data_seqcount, seq));        \
 164         return size;                                                    \
 165 }                                                                       \
 166                                                                         \
 167 static inline void                                                      \
 168 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 169 {                                                                       \
 170         preempt_disable();                                              \
 171         write_seqcount_begin(&dev->data_seqcount);                      \
 172         dev->name = size;                                               \
 173         write_seqcount_end(&dev->data_seqcount);                        \
 174         preempt_enable();                                               \
 175 }
 176 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
 177 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 178 static inline u64                                                       \
 179 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 180 {                                                                       \
 181         u64 size;                                                       \
 182                                                                         \
 183         preempt_disable();                                              \
 184         size = dev->name;                                               \
 185         preempt_enable();                                               \
 186         return size;                                                    \
 187 }                                                                       \
 188                                                                         \
 189 static inline void                                                      \
 190 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 191 {                                                                       \
 192         preempt_disable();                                              \
 193         dev->name = size;                                               \
 194         preempt_enable();                                               \
 195 }
 196 #else
 197 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 198 static inline u64                                                       \
 199 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 200 {                                                                       \
 201         return dev->name;                                               \
 202 }                                                                       \
 203                                                                         \
 204 static inline void                                                      \
 205 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 206 {                                                                       \
 207         dev->name = size;                                               \
 208 }
 209 #endif
 210
 211 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
 212 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
 213 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
 214
 215 enum btrfs_chunk_allocation_policy {
 216         BTRFS_CHUNK_ALLOC_REGULAR,
 217 };
 218
 219 /*
 220  * Read policies for mirrored block group profiles, read picks the stripe based
 221  * on these policies.
 222  */
 223 enum btrfs_read_policy {
 224         /* Use process PID to choose the stripe */
 225         BTRFS_READ_POLICY_PID,
 226         BTRFS_NR_READ_POLICY,
 227 };
 228
 229 struct btrfs_fs_devices {
 230         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 231         u8 metadata_uuid[BTRFS_FSID_SIZE];
 232         bool fsid_change;
 233         struct list_head fs_list;
 234
 235         u64 num_devices;
 236         u64 open_devices;
 237         u64 rw_devices;
 238         u64 missing_devices;
 239         u64 total_rw_bytes;
 240         u64 total_devices;
 241
 242         /* Highest generation number of seen devices */
 243         u64 latest_generation;
 244
 245         struct block_device *latest_bdev;
 246
 247         /* all of the devices in the FS, protected by a mutex
 248          * so we can safely walk it to write out the supers without
 249          * worrying about add/remove by the multi-device code.
 250          * Scrubbing super can kick off supers writing by holding
 251          * this mutex lock.
 252          */
 253         struct mutex device_list_mutex;
 254
 255         /* List of all devices, protected by device_list_mutex */
 256         struct list_head devices;
 257
 258         /*
 259          * Devices which can satisfy space allocation. Protected by
 260          * chunk_mutex
 261          */
 262         struct list_head alloc_list;
 263
 264         struct list_head seed_list;
 265         bool seeding;
 266
 267         int opened;
 268
 269         /* set when we find or add a device that doesn't have the
 270          * nonrot flag set
 271          */
 272         bool rotating;
 273
 274         struct btrfs_fs_info *fs_info;
 275         /* sysfs kobjects */
 276         struct kobject fsid_kobj;
 277         struct kobject *devices_kobj;
 278         struct kobject *devinfo_kobj;
 279         struct completion kobj_unregister;
 280
 281         enum btrfs_chunk_allocation_policy chunk_alloc_policy;
 282
 283         /* Policy used to read the mirrored stripes */
 284         enum btrfs_read_policy read_policy;
 285 };
 286
 287 #define BTRFS_BIO_INLINE_CSUM_SIZE      64
 288
 289 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)        \
 290                         - sizeof(struct btrfs_chunk))           \
 291                         / sizeof(struct btrfs_stripe) + 1)
 292
 293 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE        \
 294                                 - 2 * sizeof(struct btrfs_disk_key)     \
 295                                 - 2 * sizeof(struct btrfs_chunk))       \
 296                                 / sizeof(struct btrfs_stripe) + 1)
 297
 298 /*
 299  * we need the mirror number and stripe index to be passed around
 300  * the call chain while we are processing end_io (especially errors).
 301  * Really, what we need is a btrfs_bio structure that has this info
 302  * and is properly sized with its stripe array, but we're not there
 303  * quite yet.  We have our own btrfs bioset, and all of the bios
 304  * we allocate are actually btrfs_io_bios.  We'll cram as much of
 305  * struct btrfs_bio as we can into this over time.
 306  */
 307 struct btrfs_io_bio {
 308         unsigned int mirror_num;
 309         struct btrfs_device *device;
 310         u64 logical;
 311         u8 *csum;
 312         u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
 313         struct bvec_iter iter;
 314         /*
 315          * This member must come last, bio_alloc_bioset will allocate enough
 316          * bytes for entire btrfs_io_bio but relies on bio being last.
 317          */
 318         struct bio bio;
 319 };
 320
 321 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
 322 {
 323         return container_of(bio, struct btrfs_io_bio, bio);
 324 }
 325
 326 static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
 327 {
 328         if (io_bio->csum != io_bio->csum_inline) {
 329                 kfree(io_bio->csum);
 330                 io_bio->csum = NULL;
 331         }
 332 }
 333
 334 struct btrfs_bio_stripe {
 335         struct btrfs_device *dev;
 336         u64 physical;
 337         u64 length; /* only used for discard mappings */
 338 };
 339
 340 struct btrfs_bio {
 341         refcount_t refs;
 342         atomic_t stripes_pending;
 343         struct btrfs_fs_info *fs_info;
 344         u64 map_type; /* get from map_lookup->type */
 345         bio_end_io_t *end_io;
 346         struct bio *orig_bio;
 347         void *private;
 348         atomic_t error;
 349         int max_errors;
 350         int num_stripes;
 351         int mirror_num;
 352         int num_tgtdevs;
 353         int *tgtdev_map;
 354         /*
 355          * logical block numbers for the start of each stripe
 356          * The last one or two are p/q.  These are sorted,
 357          * so raid_map[0] is the start of our full stripe
 358          */
 359         u64 *raid_map;
 360         struct btrfs_bio_stripe stripes[];
 361 };
 362
 363 struct btrfs_device_info {
 364         struct btrfs_device *dev;
 365         u64 dev_offset;
 366         u64 max_avail;
 367         u64 total_avail;
 368 };
 369
 370 struct btrfs_raid_attr {
 371         u8 sub_stripes;         /* sub_stripes info for map */
 372         u8 dev_stripes;         /* stripes per dev */
 373         u8 devs_max;            /* max devs to use */
 374         u8 devs_min;            /* min devs needed */
 375         u8 tolerated_failures;  /* max tolerated fail devs */
 376         u8 devs_increment;      /* ndevs has to be a multiple of this */
 377         u8 ncopies;             /* how many copies to data has */
 378         u8 nparity;             /* number of stripes worth of bytes to store
 379                                  * parity information */
 380         u8 mindev_error;        /* error code if min devs requisite is unmet */
 381         const char raid_name[8]; /* name of the raid */
 382         u64 bg_flag;            /* block group flag of the raid */
 383 };
 384
 385 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
 386
 387 struct map_lookup {
 388         u64 type;
 389         int io_align;
 390         int io_width;
 391         u64 stripe_len;
 392         int num_stripes;
 393         int sub_stripes;
 394         int verified_stripes; /* For mount time dev extent verification */
 395         struct btrfs_bio_stripe stripes[];
 396 };
 397
 398 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
 399                             (sizeof(struct btrfs_bio_stripe) * (n)))
 400
 401 struct btrfs_balance_args;
 402 struct btrfs_balance_progress;
 403 struct btrfs_balance_control {
 404         struct btrfs_balance_args data;
 405         struct btrfs_balance_args meta;
 406         struct btrfs_balance_args sys;
 407
 408         u64 flags;
 409
 410         struct btrfs_balance_progress stat;
 411 };
 412
 413 enum btrfs_map_op {
 414         BTRFS_MAP_READ,
 415         BTRFS_MAP_WRITE,
 416         BTRFS_MAP_DISCARD,
 417         BTRFS_MAP_GET_READ_MIRRORS,
 418 };
 419
 420 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
 421 {
 422         switch (bio_op(bio)) {
 423         case REQ_OP_DISCARD:
 424                 return BTRFS_MAP_DISCARD;
 425         case REQ_OP_WRITE:
 426                 return BTRFS_MAP_WRITE;
 427         default:
 428                 WARN_ON_ONCE(1);
 429                 fallthrough;
 430         case REQ_OP_READ:
 431                 return BTRFS_MAP_READ;
 432         }
 433 }
 434
 435 void btrfs_get_bbio(struct btrfs_bio *bbio);
 436 void btrfs_put_bbio(struct btrfs_bio *bbio);
 437 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 438                     u64 logical, u64 *length,
 439                     struct btrfs_bio **bbio_ret, int mirror_num);
 440 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 441                      u64 logical, u64 *length,
 442                      struct btrfs_bio **bbio_ret);
 443 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 444                 u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
 445 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
 446 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
 447 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
 448 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
 449 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 450                            int mirror_num);
 451 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 452                        fmode_t flags, void *holder);
 453 struct btrfs_device *btrfs_scan_one_device(const char *path,
 454                                            fmode_t flags, void *holder);
 455 int btrfs_forget_devices(const char *path);
 456 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
 457 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
 458 void btrfs_assign_next_active_device(struct btrfs_device *device,
 459                                      struct btrfs_device *this_dev);
 460 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
 461                                                   u64 devid,
 462                                                   const char *devpath);
 463 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
 464                                         const u64 *devid,
 465                                         const u8 *uuid);
 466 void btrfs_free_device(struct btrfs_device *device);
 467 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 468                     const char *device_path, u64 devid);
 469 void __exit btrfs_cleanup_fs_uuids(void);
 470 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
 471 int btrfs_grow_device(struct btrfs_trans_handle *trans,
 472                       struct btrfs_device *device, u64 new_size);
 473 struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
 474                                        u64 devid, u8 *uuid, u8 *fsid);
 475 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
 476 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
 477 int btrfs_balance(struct btrfs_fs_info *fs_info,
 478                   struct btrfs_balance_control *bctl,
 479                   struct btrfs_ioctl_balance_args *bargs);
 480 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
 481 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
 482 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
 483 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
 484 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
 485 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
 486 int btrfs_uuid_scan_kthread(void *data);
 487 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
 488 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
 489                          u64 *start, u64 *max_avail);
 490 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
 491 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
 492                         struct btrfs_ioctl_get_dev_stats *stats);
 493 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
 494 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
 495 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
 496 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
 497 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
 498 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
 499 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
 500                            u64 logical, u64 len);
 501 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
 502                                     u64 logical);
 503 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
 504                              u64 chunk_offset, u64 chunk_size);
 505 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
 506 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
 507                                        u64 logical, u64 length);
 508 void btrfs_release_disk_super(struct btrfs_super_block *super);
 509
 510 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
 511                                       int index)
 512 {
 513         atomic_inc(dev->dev_stat_values + index);
 514         /*
 515          * This memory barrier orders stores updating statistics before stores
 516          * updating dev_stats_ccnt.
 517          *
 518          * It pairs with smp_rmb() in btrfs_run_dev_stats().
 519          */
 520         smp_mb__before_atomic();
 521         atomic_inc(&dev->dev_stats_ccnt);
 522 }
 523
 524 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
 525                                       int index)
 526 {
 527         return atomic_read(dev->dev_stat_values + index);
 528 }
 529
 530 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
 531                                                 int index)
 532 {
 533         int ret;
 534
 535         ret = atomic_xchg(dev->dev_stat_values + index, 0);
 536         /*
 537          * atomic_xchg implies a full memory barriers as per atomic_t.txt:
 538          * - RMW operations that have a return value are fully ordered;
 539          *
 540          * This implicit memory barriers is paired with the smp_rmb in
 541          * btrfs_run_dev_stats
 542          */
 543         atomic_inc(&dev->dev_stats_ccnt);
 544         return ret;
 545 }
 546
 547 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
 548                                       int index, unsigned long val)
 549 {
 550         atomic_set(dev->dev_stat_values + index, val);
 551         /*
 552          * This memory barrier orders stores updating statistics before stores
 553          * updating dev_stats_ccnt.
 554          *
 555          * It pairs with smp_rmb() in btrfs_run_dev_stats().
 556          */
 557         smp_mb__before_atomic();
 558         atomic_inc(&dev->dev_stats_ccnt);
 559 }
 560
 561 /*
 562  * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
 563  * can be used as index to access btrfs_raid_array[].
 564  */
 565 static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
 566 {
 567         if (flags & BTRFS_BLOCK_GROUP_RAID10)
 568                 return BTRFS_RAID_RAID10;
 569         else if (flags & BTRFS_BLOCK_GROUP_RAID1)
 570                 return BTRFS_RAID_RAID1;
 571         else if (flags & BTRFS_BLOCK_GROUP_RAID1C3)
 572                 return BTRFS_RAID_RAID1C3;
 573         else if (flags & BTRFS_BLOCK_GROUP_RAID1C4)
 574                 return BTRFS_RAID_RAID1C4;
 575         else if (flags & BTRFS_BLOCK_GROUP_DUP)
 576                 return BTRFS_RAID_DUP;
 577         else if (flags & BTRFS_BLOCK_GROUP_RAID0)
 578                 return BTRFS_RAID_RAID0;
 579         else if (flags & BTRFS_BLOCK_GROUP_RAID5)
 580                 return BTRFS_RAID_RAID5;
 581         else if (flags & BTRFS_BLOCK_GROUP_RAID6)
 582                 return BTRFS_RAID_RAID6;
 583
 584         return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
 585 }
 586
 587 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
 588
 589 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
 590 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
 591                                         struct btrfs_device *failing_dev);
 592 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
 593                                struct block_device *bdev,
 594                                const char *device_path);
 595
 596 int btrfs_bg_type_to_factor(u64 flags);
 597 const char *btrfs_bg_type_to_raid_name(u64 flags);
 598 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
 599
 600 #endif