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         /* Bandwidth limit for scrub, in bytes */
 148         u64 scrub_speed_max;
 149 };
 150
 151 /*
 152  * If we read those variants at the context of their own lock, we needn't
 153  * use the following helpers, reading them directly is safe.
 154  */
 155 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 156 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 157 static inline u64                                                       \
 158 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 159 {                                                                       \
 160         u64 size;                                                       \
 161         unsigned int seq;                                               \
 162                                                                         \
 163         do {                                                            \
 164                 seq = read_seqcount_begin(&dev->data_seqcount);         \
 165                 size = dev->name;                                       \
 166         } while (read_seqcount_retry(&dev->data_seqcount, seq));        \
 167         return size;                                                    \
 168 }                                                                       \
 169                                                                         \
 170 static inline void                                                      \
 171 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 172 {                                                                       \
 173         preempt_disable();                                              \
 174         write_seqcount_begin(&dev->data_seqcount);                      \
 175         dev->name = size;                                               \
 176         write_seqcount_end(&dev->data_seqcount);                        \
 177         preempt_enable();                                               \
 178 }
 179 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
 180 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 181 static inline u64                                                       \
 182 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 183 {                                                                       \
 184         u64 size;                                                       \
 185                                                                         \
 186         preempt_disable();                                              \
 187         size = dev->name;                                               \
 188         preempt_enable();                                               \
 189         return size;                                                    \
 190 }                                                                       \
 191                                                                         \
 192 static inline void                                                      \
 193 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 194 {                                                                       \
 195         preempt_disable();                                              \
 196         dev->name = size;                                               \
 197         preempt_enable();                                               \
 198 }
 199 #else
 200 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 201 static inline u64                                                       \
 202 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 203 {                                                                       \
 204         return dev->name;                                               \
 205 }                                                                       \
 206                                                                         \
 207 static inline void                                                      \
 208 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 209 {                                                                       \
 210         dev->name = size;                                               \
 211 }
 212 #endif
 213
 214 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
 215 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
 216 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
 217
 218 enum btrfs_chunk_allocation_policy {
 219         BTRFS_CHUNK_ALLOC_REGULAR,
 220         BTRFS_CHUNK_ALLOC_ZONED,
 221 };
 222
 223 /*
 224  * Read policies for mirrored block group profiles, read picks the stripe based
 225  * on these policies.
 226  */
 227 enum btrfs_read_policy {
 228         /* Use process PID to choose the stripe */
 229         BTRFS_READ_POLICY_PID,
 230         BTRFS_NR_READ_POLICY,
 231 };
 232
 233 struct btrfs_fs_devices {
 234         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 235         u8 metadata_uuid[BTRFS_FSID_SIZE];
 236         bool fsid_change;
 237         struct list_head fs_list;
 238
 239         u64 num_devices;
 240         u64 open_devices;
 241         u64 rw_devices;
 242         u64 missing_devices;
 243         u64 total_rw_bytes;
 244         u64 total_devices;
 245
 246         /* Highest generation number of seen devices */
 247         u64 latest_generation;
 248
 249         struct block_device *latest_bdev;
 250
 251         /* all of the devices in the FS, protected by a mutex
 252          * so we can safely walk it to write out the supers without
 253          * worrying about add/remove by the multi-device code.
 254          * Scrubbing super can kick off supers writing by holding
 255          * this mutex lock.
 256          */
 257         struct mutex device_list_mutex;
 258
 259         /* List of all devices, protected by device_list_mutex */
 260         struct list_head devices;
 261
 262         /*
 263          * Devices which can satisfy space allocation. Protected by
 264          * chunk_mutex
 265          */
 266         struct list_head alloc_list;
 267
 268         struct list_head seed_list;
 269         bool seeding;
 270
 271         int opened;
 272
 273         /* set when we find or add a device that doesn't have the
 274          * nonrot flag set
 275          */
 276         bool rotating;
 277
 278         struct btrfs_fs_info *fs_info;
 279         /* sysfs kobjects */
 280         struct kobject fsid_kobj;
 281         struct kobject *devices_kobj;
 282         struct kobject *devinfo_kobj;
 283         struct completion kobj_unregister;
 284
 285         enum btrfs_chunk_allocation_policy chunk_alloc_policy;
 286
 287         /* Policy used to read the mirrored stripes */
 288         enum btrfs_read_policy read_policy;
 289 };
 290
 291 #define BTRFS_BIO_INLINE_CSUM_SIZE      64
 292
 293 #define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)        \
 294                         - sizeof(struct btrfs_chunk))           \
 295                         / sizeof(struct btrfs_stripe) + 1)
 296
 297 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE        \
 298                                 - 2 * sizeof(struct btrfs_disk_key)     \
 299                                 - 2 * sizeof(struct btrfs_chunk))       \
 300                                 / sizeof(struct btrfs_stripe) + 1)
 301
 302 /*
 303  * we need the mirror number and stripe index to be passed around
 304  * the call chain while we are processing end_io (especially errors).
 305  * Really, what we need is a btrfs_bio structure that has this info
 306  * and is properly sized with its stripe array, but we're not there
 307  * quite yet.  We have our own btrfs bioset, and all of the bios
 308  * we allocate are actually btrfs_io_bios.  We'll cram as much of
 309  * struct btrfs_bio as we can into this over time.
 310  */
 311 struct btrfs_io_bio {
 312         unsigned int mirror_num;
 313         struct btrfs_device *device;
 314         u64 logical;
 315         u8 *csum;
 316         u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
 317         struct bvec_iter iter;
 318         /*
 319          * This member must come last, bio_alloc_bioset will allocate enough
 320          * bytes for entire btrfs_io_bio but relies on bio being last.
 321          */
 322         struct bio bio;
 323 };
 324
 325 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
 326 {
 327         return container_of(bio, struct btrfs_io_bio, bio);
 328 }
 329
 330 static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
 331 {
 332         if (io_bio->csum != io_bio->csum_inline) {
 333                 kfree(io_bio->csum);
 334                 io_bio->csum = NULL;
 335         }
 336 }
 337
 338 struct btrfs_bio_stripe {
 339         struct btrfs_device *dev;
 340         u64 physical;
 341         u64 length; /* only used for discard mappings */
 342 };
 343
 344 struct btrfs_bio {
 345         refcount_t refs;
 346         atomic_t stripes_pending;
 347         struct btrfs_fs_info *fs_info;
 348         u64 map_type; /* get from map_lookup->type */
 349         bio_end_io_t *end_io;
 350         struct bio *orig_bio;
 351         void *private;
 352         atomic_t error;
 353         int max_errors;
 354         int num_stripes;
 355         int mirror_num;
 356         int num_tgtdevs;
 357         int *tgtdev_map;
 358         /*
 359          * logical block numbers for the start of each stripe
 360          * The last one or two are p/q.  These are sorted,
 361          * so raid_map[0] is the start of our full stripe
 362          */
 363         u64 *raid_map;
 364         struct btrfs_bio_stripe stripes[];
 365 };
 366
 367 struct btrfs_device_info {
 368         struct btrfs_device *dev;
 369         u64 dev_offset;
 370         u64 max_avail;
 371         u64 total_avail;
 372 };
 373
 374 struct btrfs_raid_attr {
 375         u8 sub_stripes;         /* sub_stripes info for map */
 376         u8 dev_stripes;         /* stripes per dev */
 377         u8 devs_max;            /* max devs to use */
 378         u8 devs_min;            /* min devs needed */
 379         u8 tolerated_failures;  /* max tolerated fail devs */
 380         u8 devs_increment;      /* ndevs has to be a multiple of this */
 381         u8 ncopies;             /* how many copies to data has */
 382         u8 nparity;             /* number of stripes worth of bytes to store
 383                                  * parity information */
 384         u8 mindev_error;        /* error code if min devs requisite is unmet */
 385         const char raid_name[8]; /* name of the raid */
 386         u64 bg_flag;            /* block group flag of the raid */
 387 };
 388
 389 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
 390
 391 struct map_lookup {
 392         u64 type;
 393         int io_align;
 394         int io_width;
 395         u64 stripe_len;
 396         int num_stripes;
 397         int sub_stripes;
 398         int verified_stripes; /* For mount time dev extent verification */
 399         struct btrfs_bio_stripe stripes[];
 400 };
 401
 402 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
 403                             (sizeof(struct btrfs_bio_stripe) * (n)))
 404
 405 struct btrfs_balance_args;
 406 struct btrfs_balance_progress;
 407 struct btrfs_balance_control {
 408         struct btrfs_balance_args data;
 409         struct btrfs_balance_args meta;
 410         struct btrfs_balance_args sys;
 411
 412         u64 flags;
 413
 414         struct btrfs_balance_progress stat;
 415 };
 416
 417 enum btrfs_map_op {
 418         BTRFS_MAP_READ,
 419         BTRFS_MAP_WRITE,
 420         BTRFS_MAP_DISCARD,
 421         BTRFS_MAP_GET_READ_MIRRORS,
 422 };
 423
 424 static inline enum btrfs_map_op btrfs_op(struct bio *bio)
 425 {
 426         switch (bio_op(bio)) {
 427         case REQ_OP_DISCARD:
 428                 return BTRFS_MAP_DISCARD;
 429         case REQ_OP_WRITE:
 430         case REQ_OP_ZONE_APPEND:
 431                 return BTRFS_MAP_WRITE;
 432         default:
 433                 WARN_ON_ONCE(1);
 434                 fallthrough;
 435         case REQ_OP_READ:
 436                 return BTRFS_MAP_READ;
 437         }
 438 }
 439
 440 void btrfs_get_bbio(struct btrfs_bio *bbio);
 441 void btrfs_put_bbio(struct btrfs_bio *bbio);
 442 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 443                     u64 logical, u64 *length,
 444                     struct btrfs_bio **bbio_ret, int mirror_num);
 445 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 446                      u64 logical, u64 *length,
 447                      struct btrfs_bio **bbio_ret);
 448 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *map,
 449                           enum btrfs_map_op op, u64 logical,
 450                           struct btrfs_io_geometry *io_geom);
 451 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
 452 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
 453 struct btrfs_block_group *btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 454                                             u64 type);
 455 void btrfs_mapping_tree_free(struct extent_map_tree *tree);
 456 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 457                            int mirror_num);
 458 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 459                        fmode_t flags, void *holder);
 460 struct btrfs_device *btrfs_scan_one_device(const char *path,
 461                                            fmode_t flags, void *holder);
 462 int btrfs_forget_devices(const char *path);
 463 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
 464 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
 465 void btrfs_assign_next_active_device(struct btrfs_device *device,
 466                                      struct btrfs_device *this_dev);
 467 struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
 468                                                   u64 devid,
 469                                                   const char *devpath);
 470 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
 471                                         const u64 *devid,
 472                                         const u8 *uuid);
 473 void btrfs_free_device(struct btrfs_device *device);
 474 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 475                     const char *device_path, u64 devid,
 476                     struct block_device **bdev, fmode_t *mode);
 477 void __exit btrfs_cleanup_fs_uuids(void);
 478 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
 479 int btrfs_grow_device(struct btrfs_trans_handle *trans,
 480                       struct btrfs_device *device, u64 new_size);
 481 struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
 482                                        u64 devid, u8 *uuid, u8 *fsid);
 483 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
 484 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
 485 int btrfs_balance(struct btrfs_fs_info *fs_info,
 486                   struct btrfs_balance_control *bctl,
 487                   struct btrfs_ioctl_balance_args *bargs);
 488 void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
 489 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
 490 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
 491 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
 492 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
 493 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
 494 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
 495 int btrfs_uuid_scan_kthread(void *data);
 496 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
 497 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
 498                          u64 *start, u64 *max_avail);
 499 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
 500 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
 501                         struct btrfs_ioctl_get_dev_stats *stats);
 502 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
 503 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
 504 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
 505 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
 506 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
 507 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
 508 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
 509                            u64 logical, u64 len);
 510 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
 511                                     u64 logical);
 512 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
 513                                      struct btrfs_block_group *bg);
 514 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
 515 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
 516                                        u64 logical, u64 length);
 517 void btrfs_release_disk_super(struct btrfs_super_block *super);
 518
 519 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
 520                                       int index)
 521 {
 522         atomic_inc(dev->dev_stat_values + index);
 523         /*
 524          * This memory barrier orders stores updating statistics before stores
 525          * updating dev_stats_ccnt.
 526          *
 527          * It pairs with smp_rmb() in btrfs_run_dev_stats().
 528          */
 529         smp_mb__before_atomic();
 530         atomic_inc(&dev->dev_stats_ccnt);
 531 }
 532
 533 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
 534                                       int index)
 535 {
 536         return atomic_read(dev->dev_stat_values + index);
 537 }
 538
 539 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
 540                                                 int index)
 541 {
 542         int ret;
 543
 544         ret = atomic_xchg(dev->dev_stat_values + index, 0);
 545         /*
 546          * atomic_xchg implies a full memory barriers as per atomic_t.txt:
 547          * - RMW operations that have a return value are fully ordered;
 548          *
 549          * This implicit memory barriers is paired with the smp_rmb in
 550          * btrfs_run_dev_stats
 551          */
 552         atomic_inc(&dev->dev_stats_ccnt);
 553         return ret;
 554 }
 555
 556 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
 557                                       int index, unsigned long val)
 558 {
 559         atomic_set(dev->dev_stat_values + index, val);
 560         /*
 561          * This memory barrier orders stores updating statistics before stores
 562          * updating dev_stats_ccnt.
 563          *
 564          * It pairs with smp_rmb() in btrfs_run_dev_stats().
 565          */
 566         smp_mb__before_atomic();
 567         atomic_inc(&dev->dev_stats_ccnt);
 568 }
 569
 570 void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
 571
 572 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
 573 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
 574                                         struct btrfs_device *failing_dev);
 575 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
 576                                struct block_device *bdev,
 577                                const char *device_path);
 578
 579 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
 580 int btrfs_bg_type_to_factor(u64 flags);
 581 const char *btrfs_bg_type_to_raid_name(u64 flags);
 582 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
 583 int btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
 584
 585 #endif