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 extern struct mutex uuid_mutex;
  28
  29 #define BTRFS_STRIPE_LEN        SZ_64K
  30
  31 struct buffer_head;
  32 struct btrfs_pending_bios {
  33         struct bio *head;
  34         struct bio *tail;
  35 };
  36
  37 /*
  38  * Use sequence counter to get consistent device stat data on
  39  * 32-bit processors.
  40  */
  41 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  42 #include <linux/seqlock.h>
  43 #define __BTRFS_NEED_DEVICE_DATA_ORDERED
  44 #define btrfs_device_data_ordered_init(device)  \
  45         seqcount_init(&device->data_seqcount)
  46 #else
  47 #define btrfs_device_data_ordered_init(device) do { } while (0)
  48 #endif
  49
  50 struct btrfs_device {
  51         struct list_head dev_list;
  52         struct list_head dev_alloc_list;
  53         struct btrfs_fs_devices *fs_devices;
  54
  55         struct btrfs_root *dev_root;
  56
  57         struct rcu_string *name;
  58
  59         u64 generation;
  60
  61         spinlock_t io_lock ____cacheline_aligned;
  62         int running_pending;
  63         /* regular prio bios */
  64         struct btrfs_pending_bios pending_bios;
  65         /* WRITE_SYNC bios */
  66         struct btrfs_pending_bios pending_sync_bios;
  67
  68         struct block_device *bdev;
  69
  70         /* the mode sent to blkdev_get */
  71         fmode_t mode;
  72
  73         int writeable;
  74         int in_fs_metadata;
  75         int missing;
  76         int can_discard;
  77         int is_tgtdev_for_dev_replace;
  78
  79 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
  80         seqcount_t data_seqcount;
  81 #endif
  82
  83         /* the internal btrfs device id */
  84         u64 devid;
  85
  86         /* size of the device in memory */
  87         u64 total_bytes;
  88
  89         /* size of the device on disk */
  90         u64 disk_total_bytes;
  91
  92         /* bytes used */
  93         u64 bytes_used;
  94
  95         /* optimal io alignment for this device */
  96         u32 io_align;
  97
  98         /* optimal io width for this device */
  99         u32 io_width;
 100         /* type and info about this device */
 101         u64 type;
 102
 103         /* minimal io size for this device */
 104         u32 sector_size;
 105
 106         /* physical drive uuid (or lvm uuid) */
 107         u8 uuid[BTRFS_UUID_SIZE];
 108
 109         /*
 110          * size of the device on the current transaction
 111          *
 112          * This variant is update when committing the transaction,
 113          * and protected by device_list_mutex
 114          */
 115         u64 commit_total_bytes;
 116
 117         /* bytes used on the current transaction */
 118         u64 commit_bytes_used;
 119         /*
 120          * used to manage the device which is resized
 121          *
 122          * It is protected by chunk_lock.
 123          */
 124         struct list_head resized_list;
 125
 126         /* for sending down flush barriers */
 127         int nobarriers;
 128         struct bio *flush_bio;
 129         struct completion flush_wait;
 130
 131         /* per-device scrub information */
 132         struct scrub_ctx *scrub_device;
 133
 134         struct btrfs_work work;
 135         struct rcu_head rcu;
 136         struct work_struct rcu_work;
 137
 138         /* readahead state */
 139         spinlock_t reada_lock;
 140         atomic_t reada_in_flight;
 141         u64 reada_next;
 142         struct reada_zone *reada_curr_zone;
 143         struct radix_tree_root reada_zones;
 144         struct radix_tree_root reada_extents;
 145
 146         /* disk I/O failure stats. For detailed description refer to
 147          * enum btrfs_dev_stat_values in ioctl.h */
 148         int dev_stats_valid;
 149
 150         /* Counter to record the change of device stats */
 151         atomic_t dev_stats_ccnt;
 152         atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
 153 };
 154
 155 /*
 156  * If we read those variants at the context of their own lock, we needn't
 157  * use the following helpers, reading them directly is safe.
 158  */
 159 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 160 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 161 static inline u64                                                       \
 162 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 163 {                                                                       \
 164         u64 size;                                                       \
 165         unsigned int seq;                                               \
 166                                                                         \
 167         do {                                                            \
 168                 seq = read_seqcount_begin(&dev->data_seqcount);         \
 169                 size = dev->name;                                       \
 170         } while (read_seqcount_retry(&dev->data_seqcount, seq));        \
 171         return size;                                                    \
 172 }                                                                       \
 173                                                                         \
 174 static inline void                                                      \
 175 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 176 {                                                                       \
 177         preempt_disable();                                              \
 178         write_seqcount_begin(&dev->data_seqcount);                      \
 179         dev->name = size;                                               \
 180         write_seqcount_end(&dev->data_seqcount);                        \
 181         preempt_enable();                                               \
 182 }
 183 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
 184 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 185 static inline u64                                                       \
 186 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 187 {                                                                       \
 188         u64 size;                                                       \
 189                                                                         \
 190         preempt_disable();                                              \
 191         size = dev->name;                                               \
 192         preempt_enable();                                               \
 193         return size;                                                    \
 194 }                                                                       \
 195                                                                         \
 196 static inline void                                                      \
 197 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 198 {                                                                       \
 199         preempt_disable();                                              \
 200         dev->name = size;                                               \
 201         preempt_enable();                                               \
 202 }
 203 #else
 204 #define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
 205 static inline u64                                                       \
 206 btrfs_device_get_##name(const struct btrfs_device *dev)                 \
 207 {                                                                       \
 208         return dev->name;                                               \
 209 }                                                                       \
 210                                                                         \
 211 static inline void                                                      \
 212 btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
 213 {                                                                       \
 214         dev->name = size;                                               \
 215 }
 216 #endif
 217
 218 BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
 219 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
 220 BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
 221
 222 struct btrfs_fs_devices {
 223         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 224
 225         u64 num_devices;
 226         u64 open_devices;
 227         u64 rw_devices;
 228         u64 missing_devices;
 229         u64 total_rw_bytes;
 230         u64 total_devices;
 231         struct block_device *latest_bdev;
 232
 233         /* all of the devices in the FS, protected by a mutex
 234          * so we can safely walk it to write out the supers without
 235          * worrying about add/remove by the multi-device code.
 236          * Scrubbing super can kick off supers writing by holding
 237          * this mutex lock.
 238          */
 239         struct mutex device_list_mutex;
 240         struct list_head devices;
 241
 242         struct list_head resized_devices;
 243         /* devices not currently being allocated */
 244         struct list_head alloc_list;
 245         struct list_head list;
 246
 247         struct btrfs_fs_devices *seed;
 248         int seeding;
 249
 250         int opened;
 251
 252         /* set when we find or add a device that doesn't have the
 253          * nonrot flag set
 254          */
 255         int rotating;
 256
 257         struct btrfs_fs_info *fs_info;
 258         /* sysfs kobjects */
 259         struct kobject fsid_kobj;
 260         struct kobject *device_dir_kobj;
 261         struct completion kobj_unregister;
 262 };
 263
 264 #define BTRFS_BIO_INLINE_CSUM_SIZE      64
 265
 266 /*
 267  * we need the mirror number and stripe index to be passed around
 268  * the call chain while we are processing end_io (especially errors).
 269  * Really, what we need is a btrfs_bio structure that has this info
 270  * and is properly sized with its stripe array, but we're not there
 271  * quite yet.  We have our own btrfs bioset, and all of the bios
 272  * we allocate are actually btrfs_io_bios.  We'll cram as much of
 273  * struct btrfs_bio as we can into this over time.
 274  */
 275 typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
 276 struct btrfs_io_bio {
 277         unsigned int mirror_num;
 278         unsigned int stripe_index;
 279         u64 logical;
 280         u8 *csum;
 281         u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
 282         u8 *csum_allocated;
 283         btrfs_io_bio_end_io_t *end_io;
 284         struct bio bio;
 285 };
 286
 287 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
 288 {
 289         return container_of(bio, struct btrfs_io_bio, bio);
 290 }
 291
 292 struct btrfs_bio_stripe {
 293         struct btrfs_device *dev;
 294         u64 physical;
 295         u64 length; /* only used for discard mappings */
 296 };
 297
 298 struct btrfs_bio;
 299 typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
 300
 301 struct btrfs_bio {
 302         atomic_t refs;
 303         atomic_t stripes_pending;
 304         struct btrfs_fs_info *fs_info;
 305         u64 map_type; /* get from map_lookup->type */
 306         bio_end_io_t *end_io;
 307         struct bio *orig_bio;
 308         unsigned long flags;
 309         void *private;
 310         atomic_t error;
 311         int max_errors;
 312         int num_stripes;
 313         int mirror_num;
 314         int num_tgtdevs;
 315         int *tgtdev_map;
 316         /*
 317          * logical block numbers for the start of each stripe
 318          * The last one or two are p/q.  These are sorted,
 319          * so raid_map[0] is the start of our full stripe
 320          */
 321         u64 *raid_map;
 322         struct btrfs_bio_stripe stripes[];
 323 };
 324
 325 struct btrfs_device_info {
 326         struct btrfs_device *dev;
 327         u64 dev_offset;
 328         u64 max_avail;
 329         u64 total_avail;
 330 };
 331
 332 struct btrfs_raid_attr {
 333         int sub_stripes;        /* sub_stripes info for map */
 334         int dev_stripes;        /* stripes per dev */
 335         int devs_max;           /* max devs to use */
 336         int devs_min;           /* min devs needed */
 337         int tolerated_failures; /* max tolerated fail devs */
 338         int devs_increment;     /* ndevs has to be a multiple of this */
 339         int ncopies;            /* how many copies to data has */
 340 };
 341
 342 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
 343 extern const int btrfs_raid_mindev_error[BTRFS_NR_RAID_TYPES];
 344 extern const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES];
 345
 346 struct map_lookup {
 347         u64 type;
 348         int io_align;
 349         int io_width;
 350         u64 stripe_len;
 351         int sector_size;
 352         int num_stripes;
 353         int sub_stripes;
 354         struct btrfs_bio_stripe stripes[];
 355 };
 356
 357 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
 358                             (sizeof(struct btrfs_bio_stripe) * (n)))
 359
 360 struct btrfs_balance_args;
 361 struct btrfs_balance_progress;
 362 struct btrfs_balance_control {
 363         struct btrfs_fs_info *fs_info;
 364
 365         struct btrfs_balance_args data;
 366         struct btrfs_balance_args meta;
 367         struct btrfs_balance_args sys;
 368
 369         u64 flags;
 370
 371         struct btrfs_balance_progress stat;
 372 };
 373
 374 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
 375                                    u64 end, u64 *length);
 376 void btrfs_get_bbio(struct btrfs_bio *bbio);
 377 void btrfs_put_bbio(struct btrfs_bio *bbio);
 378 int btrfs_map_block(struct btrfs_fs_info *fs_info, int op,
 379                     u64 logical, u64 *length,
 380                     struct btrfs_bio **bbio_ret, int mirror_num);
 381 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int op,
 382                      u64 logical, u64 *length,
 383                      struct btrfs_bio **bbio_ret, int mirror_num,
 384                      int need_raid_map);
 385 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 386                      u64 chunk_start, u64 physical, u64 devid,
 387                      u64 **logical, int *naddrs, int *stripe_len);
 388 int btrfs_read_sys_array(struct btrfs_root *root);
 389 int btrfs_read_chunk_tree(struct btrfs_root *root);
 390 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 391                       struct btrfs_root *extent_root, u64 type);
 392 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 393 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 394 int btrfs_map_bio(struct btrfs_root *root, struct bio *bio,
 395                   int mirror_num, int async_submit);
 396 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 397                        fmode_t flags, void *holder);
 398 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
 399                           struct btrfs_fs_devices **fs_devices_ret);
 400 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
 401 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
 402 void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info,
 403                 struct btrfs_device *device, struct btrfs_device *this_dev);
 404 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
 405                                          char *device_path,
 406                                          struct btrfs_device **device);
 407 int btrfs_find_device_by_devspec(struct btrfs_root *root, u64 devid,
 408                                          char *devpath,
 409                                          struct btrfs_device **device);
 410 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
 411                                         const u64 *devid,
 412                                         const u8 *uuid);
 413 int btrfs_rm_device(struct btrfs_root *root, char *device_path, u64 devid);
 414 void btrfs_cleanup_fs_uuids(void);
 415 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
 416 int btrfs_grow_device(struct btrfs_trans_handle *trans,
 417                       struct btrfs_device *device, u64 new_size);
 418 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
 419                                        u8 *uuid, u8 *fsid);
 420 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
 421 int btrfs_init_new_device(struct btrfs_root *root, char *path);
 422 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
 423                                   struct btrfs_device *srcdev,
 424                                   struct btrfs_device **device_out);
 425 int btrfs_balance(struct btrfs_balance_control *bctl,
 426                   struct btrfs_ioctl_balance_args *bargs);
 427 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
 428 int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
 429 int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
 430 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
 431 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
 432 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
 433 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
 434 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
 435                          struct btrfs_device *device, u64 num_bytes,
 436                          u64 search_start, u64 *start, u64 *max_avail);
 437 int find_free_dev_extent(struct btrfs_trans_handle *trans,
 438                          struct btrfs_device *device, u64 num_bytes,
 439                          u64 *start, u64 *max_avail);
 440 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
 441 int btrfs_get_dev_stats(struct btrfs_root *root,
 442                         struct btrfs_ioctl_get_dev_stats *stats);
 443 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
 444 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
 445 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
 446                         struct btrfs_fs_info *fs_info);
 447 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
 448                                         struct btrfs_device *srcdev);
 449 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
 450                                       struct btrfs_device *srcdev);
 451 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 452                                       struct btrfs_device *tgtdev);
 453 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
 454                                               struct btrfs_device *tgtdev);
 455 void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path);
 456 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
 457                            u64 logical, u64 len, int mirror_num);
 458 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
 459                                     struct btrfs_mapping_tree *map_tree,
 460                                     u64 logical);
 461 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
 462                                 struct btrfs_root *extent_root,
 463                                 u64 chunk_offset, u64 chunk_size);
 464 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
 465                        struct btrfs_root *root, u64 chunk_offset);
 466
 467 static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
 468 {
 469         return atomic_read(&dev->dev_stats_ccnt);
 470 }
 471
 472 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
 473                                       int index)
 474 {
 475         atomic_inc(dev->dev_stat_values + index);
 476         smp_mb__before_atomic();
 477         atomic_inc(&dev->dev_stats_ccnt);
 478 }
 479
 480 static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
 481                                       int index)
 482 {
 483         return atomic_read(dev->dev_stat_values + index);
 484 }
 485
 486 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
 487                                                 int index)
 488 {
 489         int ret;
 490
 491         ret = atomic_xchg(dev->dev_stat_values + index, 0);
 492         smp_mb__before_atomic();
 493         atomic_inc(&dev->dev_stats_ccnt);
 494         return ret;
 495 }
 496
 497 static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
 498                                       int index, unsigned long val)
 499 {
 500         atomic_set(dev->dev_stat_values + index, val);
 501         smp_mb__before_atomic();
 502         atomic_inc(&dev->dev_stats_ccnt);
 503 }
 504
 505 static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
 506                                         int index)
 507 {
 508         btrfs_dev_stat_set(dev, index, 0);
 509 }
 510
 511 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
 512 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
 513                                         struct btrfs_transaction *transaction);
 514
 515 static inline void lock_chunks(struct btrfs_root *root)
 516 {
 517         mutex_lock(&root->fs_info->chunk_mutex);
 518 }
 519
 520 static inline void unlock_chunks(struct btrfs_root *root)
 521 {
 522         mutex_unlock(&root->fs_info->chunk_mutex);
 523 }
 524
 525 struct list_head *btrfs_get_fs_uuids(void);
 526 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
 527 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
 528
 529 #endif