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 <trace/events/btrfs.h>
   7 #include <linux/spinlock.h>
   8 #include <linux/list.h>
   9 #include <linux/kobject.h>
  10 #include <linux/lockdep.h>
  11 #include <linux/wait.h>
  12 #include <linux/rwsem.h>
  13 #include "volumes.h"
  14
  15 struct btrfs_fs_info;
  16 struct btrfs_block_group;
  17
  18 /*
  19  * Different levels for to flush space when doing space reservations.
  20  *
  21  * The higher the level, the more methods we try to reclaim space.
  22  */
  23 enum btrfs_reserve_flush_enum {
  24         /* If we are in the transaction, we can't flush anything.*/
  25         BTRFS_RESERVE_NO_FLUSH,
  26
  27         /*
  28          * Flush space by:
  29          * - Running delayed inode items
  30          * - Allocating a new chunk
  31          */
  32         BTRFS_RESERVE_FLUSH_LIMIT,
  33
  34         /*
  35          * Flush space by:
  36          * - Running delayed inode items
  37          * - Running delayed refs
  38          * - Running delalloc and waiting for ordered extents
  39          * - Allocating a new chunk
  40          * - Committing transaction
  41          */
  42         BTRFS_RESERVE_FLUSH_EVICT,
  43
  44         /*
  45          * Flush space by above mentioned methods and by:
  46          * - Running delayed iputs
  47          * - Committing transaction
  48          *
  49          * Can be interrupted by a fatal signal.
  50          */
  51         BTRFS_RESERVE_FLUSH_DATA,
  52         BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
  53         BTRFS_RESERVE_FLUSH_ALL,
  54
  55         /*
  56          * Pretty much the same as FLUSH_ALL, but can also steal space from
  57          * global rsv.
  58          *
  59          * Can be interrupted by a fatal signal.
  60          */
  61         BTRFS_RESERVE_FLUSH_ALL_STEAL,
  62
  63         /*
  64          * This is for btrfs_use_block_rsv only.  We have exhausted our block
  65          * rsv and our global block rsv.  This can happen for things like
  66          * delalloc where we are overwriting a lot of extents with a single
  67          * extent and didn't reserve enough space.  Alternatively it can happen
  68          * with delalloc where we reserve 1 extents worth for a large extent but
  69          * fragmentation leads to multiple extents being created.  This will
  70          * give us the reservation in the case of
  71          *
  72          * if (num_bytes < (space_info->total_bytes -
  73          *                  btrfs_space_info_used(space_info, false))
  74          *
  75          * Which ignores bytes_may_use.  This is potentially dangerous, but our
  76          * reservation system is generally pessimistic so is able to absorb this
  77          * style of mistake.
  78          */
  79         BTRFS_RESERVE_FLUSH_EMERGENCY,
  80 };
  81
  82 enum btrfs_flush_state {
  83         FLUSH_DELAYED_ITEMS_NR  = 1,
  84         FLUSH_DELAYED_ITEMS     = 2,
  85         FLUSH_DELAYED_REFS_NR   = 3,
  86         FLUSH_DELAYED_REFS      = 4,
  87         FLUSH_DELALLOC          = 5,
  88         FLUSH_DELALLOC_WAIT     = 6,
  89         FLUSH_DELALLOC_FULL     = 7,
  90         ALLOC_CHUNK             = 8,
  91         ALLOC_CHUNK_FORCE       = 9,
  92         RUN_DELAYED_IPUTS       = 10,
  93         COMMIT_TRANS            = 11,
  94 };
  95
  96 struct btrfs_space_info {
  97         struct btrfs_fs_info *fs_info;
  98         spinlock_t lock;
  99
 100         u64 total_bytes;        /* total bytes in the space,
 101                                    this doesn't take mirrors into account */
 102         u64 bytes_used;         /* total bytes used,
 103                                    this doesn't take mirrors into account */
 104         u64 bytes_pinned;       /* total bytes pinned, will be freed when the
 105                                    transaction finishes */
 106         u64 bytes_reserved;     /* total bytes the allocator has reserved for
 107                                    current allocations */
 108         u64 bytes_may_use;      /* number of bytes that may be used for
 109                                    delalloc/allocations */
 110         u64 bytes_readonly;     /* total bytes that are read only */
 111         u64 bytes_zone_unusable;        /* total bytes that are unusable until
 112                                            resetting the device zone */
 113
 114         u64 max_extent_size;    /* This will hold the maximum extent size of
 115                                    the space info if we had an ENOSPC in the
 116                                    allocator. */
 117         /* Chunk size in bytes */
 118         u64 chunk_size;
 119
 120         /*
 121          * Once a block group drops below this threshold (percents) we'll
 122          * schedule it for reclaim.
 123          */
 124         int bg_reclaim_threshold;
 125
 126         int clamp;              /* Used to scale our threshold for preemptive
 127                                    flushing. The value is >> clamp, so turns
 128                                    out to be a 2^clamp divisor. */
 129
 130         unsigned int full:1;    /* indicates that we cannot allocate any more
 131                                    chunks for this space */
 132         unsigned int chunk_alloc:1;     /* set if we are allocating a chunk */
 133
 134         unsigned int flush:1;           /* set if we are trying to make space */
 135
 136         unsigned int force_alloc;       /* set if we need to force a chunk
 137                                            alloc for this space */
 138
 139         u64 disk_used;          /* total bytes used on disk */
 140         u64 disk_total;         /* total bytes on disk, takes mirrors into
 141                                    account */
 142
 143         u64 flags;
 144
 145         struct list_head list;
 146         /* Protected by the spinlock 'lock'. */
 147         struct list_head ro_bgs;
 148         struct list_head priority_tickets;
 149         struct list_head tickets;
 150
 151         /*
 152          * Size of space that needs to be reclaimed in order to satisfy pending
 153          * tickets
 154          */
 155         u64 reclaim_size;
 156
 157         /*
 158          * tickets_id just indicates the next ticket will be handled, so note
 159          * it's not stored per ticket.
 160          */
 161         u64 tickets_id;
 162
 163         struct rw_semaphore groups_sem;
 164         /* for block groups in our same type */
 165         struct list_head block_groups[BTRFS_NR_RAID_TYPES];
 166
 167         struct kobject kobj;
 168         struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
 169
 170         /*
 171          * Monotonically increasing counter of block group reclaim attempts
 172          * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_count
 173          */
 174         u64 reclaim_count;
 175
 176         /*
 177          * Monotonically increasing counter of reclaimed bytes
 178          * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_bytes
 179          */
 180         u64 reclaim_bytes;
 181
 182         /*
 183          * Monotonically increasing counter of reclaim errors
 184          * Exposed in /sys/fs/<uuid>/allocation/<type>/reclaim_errors
 185          */
 186         u64 reclaim_errors;
 187
 188         /*
 189          * If true, use the dynamic relocation threshold, instead of the
 190          * fixed bg_reclaim_threshold.
 191          */
 192         bool dynamic_reclaim;
 193
 194         /*
 195          * Periodically check all block groups against the reclaim
 196          * threshold in the cleaner thread.
 197          */
 198         bool periodic_reclaim;
 199
 200         /*
 201          * Periodic reclaim should be a no-op if a space_info hasn't
 202          * freed any space since the last time we tried.
 203          */
 204         bool periodic_reclaim_ready;
 205
 206         /*
 207          * Net bytes freed or allocated since the last reclaim pass.
 208          */
 209         s64 reclaimable_bytes;
 210 };
 211
 212 struct reserve_ticket {
 213         u64 bytes;
 214         int error;
 215         bool steal;
 216         struct list_head list;
 217         wait_queue_head_t wait;
 218 };
 219
 220 static inline bool btrfs_mixed_space_info(const struct btrfs_space_info *space_info)
 221 {
 222         return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
 223                 (space_info->flags & BTRFS_BLOCK_GROUP_DATA));
 224 }
 225
 226 /*
 227  *
 228  * Declare a helper function to detect underflow of various space info members
 229  */
 230 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name)                     \
 231 static inline void                                                      \
 232 btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,           \
 233                                struct btrfs_space_info *sinfo,          \
 234                                s64 bytes)                               \
 235 {                                                                       \
 236         const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;             \
 237         lockdep_assert_held(&sinfo->lock);                              \
 238         trace_update_##name(fs_info, sinfo, sinfo->name, bytes);        \
 239         trace_btrfs_space_reservation(fs_info, trace_name,              \
 240                                       sinfo->flags, abs_bytes,          \
 241                                       bytes > 0);                       \
 242         if (bytes < 0 && sinfo->name < -bytes) {                        \
 243                 WARN_ON(1);                                             \
 244                 sinfo->name = 0;                                        \
 245                 return;                                                 \
 246         }                                                               \
 247         sinfo->name += bytes;                                           \
 248 }
 249
 250 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
 251 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
 252 DECLARE_SPACE_INFO_UPDATE(bytes_zone_unusable, "zone_unusable");
 253
 254 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
 255 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
 256                                 struct btrfs_block_group *block_group);
 257 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
 258                                         u64 chunk_size);
 259 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 260                                                u64 flags);
 261 u64 __pure btrfs_space_info_used(const struct btrfs_space_info *s_info,
 262                           bool may_use_included);
 263 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
 264 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 265                            struct btrfs_space_info *info, u64 bytes,
 266                            int dump_block_groups);
 267 int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 268                                  struct btrfs_space_info *space_info,
 269                                  u64 orig_bytes,
 270                                  enum btrfs_reserve_flush_enum flush);
 271 void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
 272                                 struct btrfs_space_info *space_info);
 273 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 274                          const struct btrfs_space_info *space_info, u64 bytes,
 275                          enum btrfs_reserve_flush_enum flush);
 276
 277 static inline void btrfs_space_info_free_bytes_may_use(
 278                                 struct btrfs_fs_info *fs_info,
 279                                 struct btrfs_space_info *space_info,
 280                                 u64 num_bytes)
 281 {
 282         spin_lock(&space_info->lock);
 283         btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
 284         btrfs_try_granting_tickets(fs_info, space_info);
 285         spin_unlock(&space_info->lock);
 286 }
 287 int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
 288                              enum btrfs_reserve_flush_enum flush);
 289 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
 290 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
 291 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
 292
 293 void btrfs_space_info_update_reclaimable(struct btrfs_space_info *space_info, s64 bytes);
 294 void btrfs_set_periodic_reclaim_ready(struct btrfs_space_info *space_info, bool ready);
 295 bool btrfs_should_periodic_reclaim(struct btrfs_space_info *space_info);
 296 int btrfs_calc_reclaim_threshold(const struct btrfs_space_info *space_info);
 297 void btrfs_reclaim_sweep(const struct btrfs_fs_info *fs_info);
 298
 299 #endif /* BTRFS_SPACE_INFO_H */