fs/btrfs/volumes.h

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #ifndef __BTRFS_VOLUMES_
  20 #define __BTRFS_VOLUMES_
  21
  22 #include <linux/bio.h>
  23 #include <linux/sort.h>
  24 #include <linux/btrfs.h>
  25 #include "async-thread.h"
  26
  27 #define BTRFS_MAX_DATA_CHUNK_SIZE       (10ULL * SZ_1G)
  28
  29 extern struct mutex uuid_mutex;
  30
  31 #define BTRFS_STRIPE_LEN        (64 * 1024)
  32
  33 struct buffer_head;
  34 struct btrfs_pending_bios {
  35         struct bio *head;
  36         struct bio *tail;
  37 };
  38
  39 /*
  40  * Use sequence counter to get consistent device stat data on
  41  * 32-bit processors.
  42  */
  43 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  44 #include <linux/seqlock.h>
  45 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
  46 #define btrfs_device_data_ordered_init(device)  \
  47         seqcount_init(&device->data_seqcount)
  48 #else
  49 #define btrfs_device_data_ordered_init(device) do { } while (0)
  50 #endif
  51
  52 struct btrfs_device {
  53         struct list_head dev_list;
  54         struct list_head dev_alloc_list;
  55         struct btrfs_fs_devices *fs_devices;
  56
  57         struct btrfs_root *dev_root;
  58
  59         struct rcu_string *name;
  60
  61         u64 generation;
  62
  63         spinlock_t io_lock ____cacheline_aligned;
  64         int running_pending;
  65         /* When true means this device has pending chunk alloc in
  66          * current transaction. Protected by chunk_mutex.
  67          */
  68         bool has_pending_chunks;
  69
  70         /* regular prio bios */
  71         struct btrfs_pending_bios pending_bios;
  72         /* WRITE_SYNC bios */
  73         struct btrfs_pending_bios pending_sync_bios;
  74
  75         struct block_device *bdev;
  76
  77         /* the mode sent to blkdev_get */
  78         fmode_t mode;
  79
  80         int writeable;
  81         int in_fs_metadata;
  82         int missing;
  83         int can_discard;
  84         int is_tgtdev_for_dev_replace;
  85
  86 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
  87         seqcount_t data_seqcount;
  88 #endif
  89
  90         /* the internal btrfs device id */
  91         u64 devid;
  92
  93         /* size of the device in memory */
  94         u64 total_bytes;
  95
  96         /* size of the device on disk */
  97         u64 disk_total_bytes;
  98
  99         /* bytes used */
 100         u64 bytes_used;
 101
 102         /* optimal io alignment for this device */
 103         u32 io_align;
 104
 105         /* optimal io width for this device */
 106         u32 io_width;
 107         /* type and info about this device */
 108         u64 type;
 109
 110         /* minimal io size for this device */
 111         u32 sector_size;
 112
 113         /* physical drive uuid (or lvm uuid) */
 114         u8 uuid[BTRFS_UUID_SIZE];
 115
 116         /*
 117          * size of the device on the current transaction
 118          *
 119          * This variant is update when committing the transaction,
 120          * and protected by device_list_mutex
 121          */
 122         u64 commit_total_bytes;
 123
 124         /* bytes used on the current transaction */
 125         u64 commit_bytes_used;
 126         /*
 127          * used to manage the device which is resized
 128          *
 129          * It is protected by chunk_lock.
 130          */
 131         struct list_head resized_list;
 132
 133         /* for sending down flush barriers */
 134         int nobarriers;
 135         struct bio *flush_bio;
 136         struct completion flush_wait;
 137
 138         /* per-device scrub information */
 139         struct scrub_ctx *scrub_device;
 140
 141         struct btrfs_work work;
 142         struct rcu_head rcu;
 143         struct work_struct rcu_work;
 144
 145         /* readahead state */
 146         spinlock_t reada_lock;
 147         atomic_t reada_in_flight;
 148         u64 reada_next;
 149         struct reada_zone *reada_curr_zone;
 150         struct radix_tree_root reada_zones;
 151         struct radix_tree_root reada_extents;
 152
 153         /* disk I/O failure stats. For detailed description refer to
 154          * enum btrfs_dev_stat_values in ioctl.h */
 155         int dev_stats_valid;
 156
 157         /* Counter to record the change of device stats */
 158         atomic_t dev_stats_ccnt;
 159         atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
 160 };
 161
 162 /*
 163  * If we read those variants at the context of their own lock, we needn't
 164  * use the following helpers, reading them directly is safe.
 165  */
 166 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 167 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 168 static inline u64                                                       \
 169 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 170 {                                                                       \
 171         u64 size;                                                       \
 172         unsigned int seq;                                               \
 173                                                                         \
 174         do {                                                            \
 175                 seq = read_seqcount_begin(&dev->data_seqcount);         \
 176                 size = dev->name;                                       \
 177         } while (read_seqcount_retry(&dev->data_seqcount, seq));        \
 178         return size;                                                    \
 179 }                                                                       \
 180                                                                         \
 181 static inline void                                                      \
 182 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 183 {                                                                       \
 184         preempt_disable();                                              \
 185         write_seqcount_begin(&dev->data_seqcount);                      \
 186         dev->name = size;                                               \
 187         write_seqcount_end(&dev->data_seqcount);                        \
 188         preempt_enable();                                               \
 189 }
 190 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
 191 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 192 static inline u64                                                       \
 193 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 194 {                                                                       \
 195         u64 size;                                                       \
 196                                                                         \
 197         preempt_disable();                                              \
 198         size = dev->name;                                               \
 199         preempt_enable();                                               \
 200         return size;                                                    \
 201 }                                                                       \
 202                                                                         \
 203 static inline void                                                      \
 204 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 205 {                                                                       \
 206         preempt_disable();                                              \
 207         dev->name = size;                                               \
 208         preempt_enable();                                               \
 209 }
 210 #else
 211 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 212 static inline u64                                                       \
 213 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 214 {                                                                       \
 215         return dev->name;                                               \
 216 }                                                                       \
 217                                                                         \
 218 static inline void                                                      \
 219 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 220 {                                                                       \
 221         dev->name = size;                                               \
 222 }
 223 #endif
 224
 225 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
 226 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
 227 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
 228
 229 struct btrfs_fs_devices {
 230         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 231
 232         u64 num_devices;
 233         u64 open_devices;
 234         u64 rw_devices;
 235         u64 missing_devices;
 236         u64 total_rw_bytes;
 237         u64 total_devices;
 238         struct block_device *latest_bdev;
 239
 240         /* all of the devices in the FS, protected by a mutex
 241          * so we can safely walk it to write out the supers without
 242          * worrying about add/remove by the multi-device code.
 243          * Scrubbing super can kick off supers writing by holding
 244          * this mutex lock.
 245          */
 246         struct mutex device_list_mutex;
 247         struct list_head devices;
 248
 249         struct list_head resized_devices;
 250         /* devices not currently being allocated */
 251         struct list_head alloc_list;
 252         struct list_head list;
 253
 254         struct btrfs_fs_devices *seed;
 255         int seeding;
 256
 257         int opened;
 258
 259         /* set when we find or add a device that doesn't have the
 260          * nonrot flag set
 261          */
 262         int rotating;
 263
 264         struct btrfs_fs_info *fs_info;
 265         /* sysfs kobjects */
 266         struct kobject fsid_kobj;
 267         struct kobject *device_dir_kobj;
 268         struct completion kobj_unregister;
 269 };
 270
 271 #define BTRFS_BIO_INLINE_CSUM_SIZE      64
 272
 273 /*
 274  * we need the mirror number and stripe index to be passed around
 275  * the call chain while we are processing end_io (especially errors).
 276  * Really, what we need is a btrfs_bio structure that has this info
 277  * and is properly sized with its stripe array, but we're not there
 278  * quite yet.  We have our own btrfs bioset, and all of the bios
 279  * we allocate are actually btrfs_io_bios.  We'll cram as much of
 280  * struct btrfs_bio as we can into this over time.
 281  */
 282 typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
 283 struct btrfs_io_bio {
 284         unsigned int mirror_num;
 285         unsigned int stripe_index;
 286         u64 logical;
 287         u8 *csum;
 288         u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
 289         u8 *csum_allocated;
 290         btrfs_io_bio_end_io_t *end_io;
 291         struct bio bio;
 292 };
 293
 294 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
 295 {
 296         return container_of(bio, struct btrfs_io_bio, bio);
 297 }
 298
 299 struct btrfs_bio_stripe {
 300         struct btrfs_device *dev;
 301         u64 physical;
 302         u64 length; /* only used for discard mappings */
 303 };
 304
 305 struct btrfs_bio;
 306 typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
 307
 308 struct btrfs_bio {
 309         atomic_t refs;
 310         atomic_t stripes_pending;
 311         struct btrfs_fs_info *fs_info;
 312         u64 map_type; /* get from map_lookup->type */
 313         bio_end_io_t *end_io;
 314         struct bio *orig_bio;
 315         void *private;
 316         atomic_t error;
 317         int max_errors;
 318         int num_stripes;
 319         int mirror_num;
 320         int num_tgtdevs;
 321         int *tgtdev_map;
 322         /*
 323          * logical block numbers for the start of each stripe
 324          * The last one or two are p/q.  These are sorted,
 325          * so raid_map[0] is the start of our full stripe
 326          */
 327         u64 *raid_map;
 328         struct btrfs_bio_stripe stripes[];
 329 };
 330
 331 struct btrfs_device_info {
 332         struct btrfs_device *dev;
 333         u64 dev_offset;
 334         u64 max_avail;
 335         u64 total_avail;
 336 };
 337
 338 struct btrfs_raid_attr {
 339         int sub_stripes;        /* sub_stripes info for map */
 340         int dev_stripes;        /* stripes per dev */
 341         int devs_max;           /* max devs to use */
 342         int devs_min;           /* min devs needed */
 343         int tolerated_failures; /* max tolerated fail devs */
 344         int devs_increment;     /* ndevs has to be a multiple of this */
 345         int ncopies;            /* how many copies to data has */
 346 };
 347
 348 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
 349
 350 extern const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES];
 351
 352 struct map_lookup {
 353         u64 type;
 354         int io_align;
 355         int io_width;
 356         int stripe_len;
 357         int sector_size;
 358         int num_stripes;
 359         int sub_stripes;
 360         struct btrfs_bio_stripe stripes[];
 361 };
 362
 363 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
 364                             (sizeof(struct btrfs_bio_stripe) * (n)))
 365
 366 /*
 367  * Restriper's general type filter
 368  */
 369 #define BTRFS_BALANCE_DATA              (1ULL << 0)
 370 #define BTRFS_BALANCE_SYSTEM            (1ULL << 1)
 371 #define BTRFS_BALANCE_METADATA          (1ULL << 2)
 372
 373 #define BTRFS_BALANCE_TYPE_MASK         (BTRFS_BALANCE_DATA |       \
 374                                          BTRFS_BALANCE_SYSTEM |     \
 375                                          BTRFS_BALANCE_METADATA)
 376
 377 #define BTRFS_BALANCE_FORCE             (1ULL << 3)
 378 #define BTRFS_BALANCE_RESUME            (1ULL << 4)
 379
 380 /*
 381  * Balance filters
 382  */
 383 #define BTRFS_BALANCE_ARGS_PROFILES     (1ULL << 0)
 384 #define BTRFS_BALANCE_ARGS_USAGE        (1ULL << 1)
 385 #define BTRFS_BALANCE_ARGS_DEVID        (1ULL << 2)
 386 #define BTRFS_BALANCE_ARGS_DRANGE       (1ULL << 3)
 387 #define BTRFS_BALANCE_ARGS_VRANGE       (1ULL << 4)
 388 #define BTRFS_BALANCE_ARGS_LIMIT        (1ULL << 5)
 389 #define BTRFS_BALANCE_ARGS_LIMIT_RANGE  (1ULL << 6)
 390 #define BTRFS_BALANCE_ARGS_STRIPES_RANGE (1ULL << 7)
 391 #define BTRFS_BALANCE_ARGS_USAGE_RANGE  (1ULL << 10)
 392
 393 #define BTRFS_BALANCE_ARGS_MASK                 \
 394         (BTRFS_BALANCE_ARGS_PROFILES |          \
 395          BTRFS_BALANCE_ARGS_USAGE |             \
 396          BTRFS_BALANCE_ARGS_DEVID |             \
 397          BTRFS_BALANCE_ARGS_DRANGE |            \
 398          BTRFS_BALANCE_ARGS_VRANGE |            \
 399          BTRFS_BALANCE_ARGS_LIMIT |             \
 400          BTRFS_BALANCE_ARGS_LIMIT_RANGE |       \
 401          BTRFS_BALANCE_ARGS_STRIPES_RANGE |     \
 402          BTRFS_BALANCE_ARGS_USAGE_RANGE)
 403
 404 /*
 405  * Profile changing flags.  When SOFT is set we won't relocate chunk if
 406  * it already has the target profile (even though it may be
 407  * half-filled).
 408  */
 409 #define BTRFS_BALANCE_ARGS_CONVERT      (1ULL << 8)
 410 #define BTRFS_BALANCE_ARGS_SOFT         (1ULL << 9)
 411
 412 struct btrfs_balance_args;
 413 struct btrfs_balance_progress;
 414 struct btrfs_balance_control {
 415         struct btrfs_fs_info *fs_info;
 416
 417         struct btrfs_balance_args data;
 418         struct btrfs_balance_args meta;
 419         struct btrfs_balance_args sys;
 420
 421         u64 flags;
 422
 423         struct btrfs_balance_progress stat;
 424 };
 425
 426 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
 427                                    u64 end, u64 *length);
 428 void btrfs_get_bbio(struct btrfs_bio *bbio);
 429 void btrfs_put_bbio(struct btrfs_bio *bbio);
 430 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 431                     u64 logical, u64 *length,
 432                     struct btrfs_bio **bbio_ret, int mirror_num);
 433 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
 434                      u64 logical, u64 *length,
 435                      struct btrfs_bio **bbio_ret, int mirror_num,
 436                      int need_raid_map);
 437 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 438                      u64 chunk_start, u64 physical, u64 devid,
 439                      u64 **logical, int *naddrs, int *stripe_len);
 440 int btrfs_read_sys_array(struct btrfs_root *root);
 441 int btrfs_read_chunk_tree(struct btrfs_root *root);
 442 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 443                       struct btrfs_root *extent_root, u64 type);
 444 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 445 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 446 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 447                   int mirror_num, int async_submit);
 448 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 449                        fmode_t flags, void *holder);
 450 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
 451                           struct btrfs_fs_devices **fs_devices_ret);
 452 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
 453 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
 454 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
 455                                          char *device_path,
 456                                          struct btrfs_device **device);
 457 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
 458                                         const u64 *devid,
 459                                         const u8 *uuid);
 460 int btrfs_rm_device(struct btrfs_root *root, char *device_path);
 461 void btrfs_cleanup_fs_uuids(void);
 462 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
 463 int btrfs_grow_device(struct btrfs_trans_handle *trans,
 464                       struct btrfs_device *device, u64 new_size);
 465 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
 466                                        u8 *uuid, u8 *fsid);
 467 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
 468 int btrfs_init_new_device(struct btrfs_root *root, char *path);
 469 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
 470                                   struct btrfs_device *srcdev,
 471                                   struct btrfs_device **device_out);
 472 int btrfs_balance(struct btrfs_balance_control *bctl,
 473                   struct btrfs_ioctl_balance_args *bargs);
 474 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
 475 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
 476 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
 477 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
 478 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
 479 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
 480 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
 481 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
 482                          struct btrfs_device *device, u64 num_bytes,
 483                          u64 search_start, u64 *start, u64 *max_avail);
 484 int find_free_dev_extent(struct btrfs_trans_handle *trans,
 485                          struct btrfs_device *device, u64 num_bytes,
 486                          u64 *start, u64 *max_avail);
 487 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
 488 int btrfs_get_dev_stats(struct btrfs_root *root,
 489                         struct btrfs_ioctl_get_dev_stats *stats);
 490 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
 491 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
 492 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
 493                         struct btrfs_fs_info *fs_info);
 494 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
 495                                         struct btrfs_device *srcdev);
 496 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
 497                                       struct btrfs_device *srcdev);
 498 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 499                                       struct btrfs_device *tgtdev);
 500 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
 501                                               struct btrfs_device *tgtdev);
 502 void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path);
 503 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
 504                            u64 logical, u64 len, int mirror_num);
 505 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
 506                                     struct btrfs_mapping_tree *map_tree,
 507                                     u64 logical);
 508 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
 509                                 struct btrfs_root *extent_root,
 510                                 u64 chunk_offset, u64 chunk_size);
 511 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
 512                        struct btrfs_root *root, u64 chunk_offset);
 513
 514 static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
 515 {
 516         return atomic_read(&dev->dev_stats_ccnt);
 517 }
 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         smp_mb__before_atomic();
 524         atomic_inc(&dev->dev_stats_ccnt);
 525 }
 526
 527 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
 528                                       int index)
 529 {
 530         return atomic_read(dev->dev_stat_values + index);
 531 }
 532
 533 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
 534                                                 int index)
 535 {
 536         int ret;
 537
 538         ret = atomic_xchg(dev->dev_stat_values + index, 0);
 539         smp_mb__before_atomic();
 540         atomic_inc(&dev->dev_stats_ccnt);
 541         return ret;
 542 }
 543
 544 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
 545                                       int index, unsigned long val)
 546 {
 547         atomic_set(dev->dev_stat_values + index, val);
 548         smp_mb__before_atomic();
 549         atomic_inc(&dev->dev_stats_ccnt);
 550 }
 551
 552 static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
 553                                         int index)
 554 {
 555         btrfs_dev_stat_set(dev, index, 0);
 556 }
 557
 558 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
 559 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
 560                                         struct btrfs_transaction *transaction);
 561
 562 static inline void lock_chunks(struct btrfs_root *root)
 563 {
 564         mutex_lock(&root->fs_info->chunk_mutex);
 565 }
 566
 567 static inline void unlock_chunks(struct btrfs_root *root)
 568 {
 569         mutex_unlock(&root->fs_info->chunk_mutex);
 570 }
 571
 572 struct list_head *btrfs_get_fs_uuids(void);
 573 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
 574 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
 575 void btrfs_close_one_device(struct btrfs_device *device);
 576
 577 #endif