fs/btrfs/space-info.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef BTRFS_SPACE_INFO_H
   4 #define BTRFS_SPACE_INFO_H
   5
   6 #include "volumes.h"
   7
   8 /*
   9  * Different levels for to flush space when doing space reservations.
  10  *
  11  * The higher the level, the more methods we try to reclaim space.
  12  */
  13 enum btrfs_reserve_flush_enum {
  14         /* If we are in the transaction, we can't flush anything.*/
  15         BTRFS_RESERVE_NO_FLUSH,
  16
  17         /*
  18          * Flush space by:
  19          * - Running delayed inode items
  20          * - Allocating a new chunk
  21          */
  22         BTRFS_RESERVE_FLUSH_LIMIT,
  23
  24         /*
  25          * Flush space by:
  26          * - Running delayed inode items
  27          * - Running delayed refs
  28          * - Running delalloc and waiting for ordered extents
  29          * - Allocating a new chunk
  30          * - Committing transaction
  31          */
  32         BTRFS_RESERVE_FLUSH_EVICT,
  33
  34         /*
  35          * Flush space by above mentioned methods and by:
  36          * - Running delayed iputs
  37          * - Committing transaction
  38          *
  39          * Can be interrupted by a fatal signal.
  40          */
  41         BTRFS_RESERVE_FLUSH_DATA,
  42         BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
  43         BTRFS_RESERVE_FLUSH_ALL,
  44
  45         /*
  46          * Pretty much the same as FLUSH_ALL, but can also steal space from
  47          * global rsv.
  48          *
  49          * Can be interrupted by a fatal signal.
  50          */
  51         BTRFS_RESERVE_FLUSH_ALL_STEAL,
  52
  53         /*
  54          * This is for btrfs_use_block_rsv only.  We have exhausted our block
  55          * rsv and our global block rsv.  This can happen for things like
  56          * delalloc where we are overwriting a lot of extents with a single
  57          * extent and didn't reserve enough space.  Alternatively it can happen
  58          * with delalloc where we reserve 1 extents worth for a large extent but
  59          * fragmentation leads to multiple extents being created.  This will
  60          * give us the reservation in the case of
  61          *
  62          * if (num_bytes < (space_info->total_bytes -
  63          *                  btrfs_space_info_used(space_info, false))
  64          *
  65          * Which ignores bytes_may_use.  This is potentially dangerous, but our
  66          * reservation system is generally pessimistic so is able to absorb this
  67          * style of mistake.
  68          */
  69         BTRFS_RESERVE_FLUSH_EMERGENCY,
  70 };
  71
  72 enum btrfs_flush_state {
  73         FLUSH_DELAYED_ITEMS_NR  = 1,
  74         FLUSH_DELAYED_ITEMS     = 2,
  75         FLUSH_DELAYED_REFS_NR   = 3,
  76         FLUSH_DELAYED_REFS      = 4,
  77         FLUSH_DELALLOC          = 5,
  78         FLUSH_DELALLOC_WAIT     = 6,
  79         FLUSH_DELALLOC_FULL     = 7,
  80         ALLOC_CHUNK             = 8,
  81         ALLOC_CHUNK_FORCE       = 9,
  82         RUN_DELAYED_IPUTS       = 10,
  83         COMMIT_TRANS            = 11,
  84 };
  85
  86 struct btrfs_space_info {
  87         spinlock_t lock;
  88
  89         u64 total_bytes;        /* total bytes in the space,
  90                                    this doesn't take mirrors into account */
  91         u64 bytes_used;         /* total bytes used,
  92                                    this doesn't take mirrors into account */
  93         u64 bytes_pinned;       /* total bytes pinned, will be freed when the
  94                                    transaction finishes */
  95         u64 bytes_reserved;     /* total bytes the allocator has reserved for
  96                                    current allocations */
  97         u64 bytes_may_use;      /* number of bytes that may be used for
  98                                    delalloc/allocations */
  99         u64 bytes_readonly;     /* total bytes that are read only */
 100         u64 bytes_zone_unusable;        /* total bytes that are unusable until
 101                                            resetting the device zone */
 102
 103         u64 max_extent_size;    /* This will hold the maximum extent size of
 104                                    the space info if we had an ENOSPC in the
 105                                    allocator. */
 106         /* Chunk size in bytes */
 107         u64 chunk_size;
 108
 109         /*
 110          * Once a block group drops below this threshold (percents) we'll
 111          * schedule it for reclaim.
 112          */
 113         int bg_reclaim_threshold;
 114
 115         int clamp;              /* Used to scale our threshold for preemptive
 116                                    flushing. The value is >> clamp, so turns
 117                                    out to be a 2^clamp divisor. */
 118
 119         unsigned int full:1;    /* indicates that we cannot allocate any more
 120                                    chunks for this space */
 121         unsigned int chunk_alloc:1;     /* set if we are allocating a chunk */
 122
 123         unsigned int flush:1;           /* set if we are trying to make space */
 124
 125         unsigned int force_alloc;       /* set if we need to force a chunk
 126                                            alloc for this space */
 127
 128         u64 disk_used;          /* total bytes used on disk */
 129         u64 disk_total;         /* total bytes on disk, takes mirrors into
 130                                    account */
 131
 132         u64 flags;
 133
 134         struct list_head list;
 135         /* Protected by the spinlock 'lock'. */
 136         struct list_head ro_bgs;
 137         struct list_head priority_tickets;
 138         struct list_head tickets;
 139
 140         /*
 141          * Size of space that needs to be reclaimed in order to satisfy pending
 142          * tickets
 143          */
 144         u64 reclaim_size;
 145
 146         /*
 147          * tickets_id just indicates the next ticket will be handled, so note
 148          * it's not stored per ticket.
 149          */
 150         u64 tickets_id;
 151
 152         struct rw_semaphore groups_sem;
 153         /* for block groups in our same type */
 154         struct list_head block_groups[BTRFS_NR_RAID_TYPES];
 155
 156         struct kobject kobj;
 157         struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
 158 };
 159
 160 struct reserve_ticket {
 161         u64 bytes;
 162         int error;
 163         bool steal;
 164         struct list_head list;
 165         wait_queue_head_t wait;
 166 };
 167
 168 static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 169 {
 170         return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
 171                 (space_info->flags & BTRFS_BLOCK_GROUP_DATA));
 172 }
 173
 174 /*
 175  *
 176  * Declare a helper function to detect underflow of various space info members
 177  */
 178 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name)                     \
 179 static inline void                                                      \
 180 btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,           \
 181                                struct btrfs_space_info *sinfo,          \
 182                                s64 bytes)                               \
 183 {                                                                       \
 184         const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;             \
 185         lockdep_assert_held(&sinfo->lock);                              \
 186         trace_update_##name(fs_info, sinfo, sinfo->name, bytes);        \
 187         trace_btrfs_space_reservation(fs_info, trace_name,              \
 188                                       sinfo->flags, abs_bytes,          \
 189                                       bytes > 0);                       \
 190         if (bytes < 0 && sinfo->name < -bytes) {                        \
 191                 WARN_ON(1);                                             \
 192                 sinfo->name = 0;                                        \
 193                 return;                                                 \
 194         }                                                               \
 195         sinfo->name += bytes;                                           \
 196 }
 197
 198 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
 199 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
 200
 201 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
 202 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
 203                                 struct btrfs_block_group *block_group);
 204 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
 205                                         u64 chunk_size);
 206 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 207                                                u64 flags);
 208 u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
 209                           bool may_use_included);
 210 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
 211 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 212                            struct btrfs_space_info *info, u64 bytes,
 213                            int dump_block_groups);
 214 int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 215                                  struct btrfs_block_rsv *block_rsv,
 216                                  u64 orig_bytes,
 217                                  enum btrfs_reserve_flush_enum flush);
 218 void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
 219                                 struct btrfs_space_info *space_info);
 220 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 221                          struct btrfs_space_info *space_info, u64 bytes,
 222                          enum btrfs_reserve_flush_enum flush);
 223
 224 static inline void btrfs_space_info_free_bytes_may_use(
 225                                 struct btrfs_fs_info *fs_info,
 226                                 struct btrfs_space_info *space_info,
 227                                 u64 num_bytes)
 228 {
 229         spin_lock(&space_info->lock);
 230         btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
 231         btrfs_try_granting_tickets(fs_info, space_info);
 232         spin_unlock(&space_info->lock);
 233 }
 234 int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
 235                              enum btrfs_reserve_flush_enum flush);
 236 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
 237 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
 238 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
 239
 240 #endif /* BTRFS_SPACE_INFO_H */