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