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