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         spinlock_t lock;
  98
  99         u64 total_bytes;        /* total bytes in the space,
 100                                    this doesn't take mirrors into account */
 101         u64 bytes_used;         /* total bytes used,
 102                                    this doesn't take mirrors into account */
 103         u64 bytes_pinned;       /* total bytes pinned, will be freed when the
 104                                    transaction finishes */
 105         u64 bytes_reserved;     /* total bytes the allocator has reserved for
 106                                    current allocations */
 107         u64 bytes_may_use;      /* number of bytes that may be used for
 108                                    delalloc/allocations */
 109         u64 bytes_readonly;     /* total bytes that are read only */
 110         u64 bytes_zone_unusable;        /* total bytes that are unusable until
 111                                            resetting the device zone */
 112
 113         u64 max_extent_size;    /* This will hold the maximum extent size of
 114                                    the space info if we had an ENOSPC in the
 115                                    allocator. */
 116         /* Chunk size in bytes */
 117         u64 chunk_size;
 118
 119         /*
 120          * Once a block group drops below this threshold (percents) we'll
 121          * schedule it for reclaim.
 122          */
 123         int bg_reclaim_threshold;
 124
 125         int clamp;              /* Used to scale our threshold for preemptive
 126                                    flushing. The value is >> clamp, so turns
 127                                    out to be a 2^clamp divisor. */
 128
 129         unsigned int full:1;    /* indicates that we cannot allocate any more
 130                                    chunks for this space */
 131         unsigned int chunk_alloc:1;     /* set if we are allocating a chunk */
 132
 133         unsigned int flush:1;           /* set if we are trying to make space */
 134
 135         unsigned int force_alloc;       /* set if we need to force a chunk
 136                                            alloc for this space */
 137
 138         u64 disk_used;          /* total bytes used on disk */
 139         u64 disk_total;         /* total bytes on disk, takes mirrors into
 140                                    account */
 141
 142         u64 flags;
 143
 144         struct list_head list;
 145         /* Protected by the spinlock 'lock'. */
 146         struct list_head ro_bgs;
 147         struct list_head priority_tickets;
 148         struct list_head tickets;
 149
 150         /*
 151          * Size of space that needs to be reclaimed in order to satisfy pending
 152          * tickets
 153          */
 154         u64 reclaim_size;
 155
 156         /*
 157          * tickets_id just indicates the next ticket will be handled, so note
 158          * it's not stored per ticket.
 159          */
 160         u64 tickets_id;
 161
 162         struct rw_semaphore groups_sem;
 163         /* for block groups in our same type */
 164         struct list_head block_groups[BTRFS_NR_RAID_TYPES];
 165
 166         struct kobject kobj;
 167         struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
 168 };
 169
 170 struct reserve_ticket {
 171         u64 bytes;
 172         int error;
 173         bool steal;
 174         struct list_head list;
 175         wait_queue_head_t wait;
 176 };
 177
 178 static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 179 {
 180         return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
 181                 (space_info->flags & BTRFS_BLOCK_GROUP_DATA));
 182 }
 183
 184 /*
 185  *
 186  * Declare a helper function to detect underflow of various space info members
 187  */
 188 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name)                     \
 189 static inline void                                                      \
 190 btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,           \
 191                                struct btrfs_space_info *sinfo,          \
 192                                s64 bytes)                               \
 193 {                                                                       \
 194         const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;             \
 195         lockdep_assert_held(&sinfo->lock);                              \
 196         trace_update_##name(fs_info, sinfo, sinfo->name, bytes);        \
 197         trace_btrfs_space_reservation(fs_info, trace_name,              \
 198                                       sinfo->flags, abs_bytes,          \
 199                                       bytes > 0);                       \
 200         if (bytes < 0 && sinfo->name < -bytes) {                        \
 201                 WARN_ON(1);                                             \
 202                 sinfo->name = 0;                                        \
 203                 return;                                                 \
 204         }                                                               \
 205         sinfo->name += bytes;                                           \
 206 }
 207
 208 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
 209 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
 210
 211 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
 212 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
 213                                 struct btrfs_block_group *block_group);
 214 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
 215                                         u64 chunk_size);
 216 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 217                                                u64 flags);
 218 u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
 219                           bool may_use_included);
 220 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
 221 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 222                            struct btrfs_space_info *info, u64 bytes,
 223                            int dump_block_groups);
 224 int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 225                                  struct btrfs_space_info *space_info,
 226                                  u64 orig_bytes,
 227                                  enum btrfs_reserve_flush_enum flush);
 228 void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
 229                                 struct btrfs_space_info *space_info);
 230 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 231                          struct btrfs_space_info *space_info, u64 bytes,
 232                          enum btrfs_reserve_flush_enum flush);
 233
 234 static inline void btrfs_space_info_free_bytes_may_use(
 235                                 struct btrfs_fs_info *fs_info,
 236                                 struct btrfs_space_info *space_info,
 237                                 u64 num_bytes)
 238 {
 239         spin_lock(&space_info->lock);
 240         btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
 241         btrfs_try_granting_tickets(fs_info, space_info);
 242         spin_unlock(&space_info->lock);
 243 }
 244 int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
 245                              enum btrfs_reserve_flush_enum flush);
 246 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
 247 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
 248 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
 249
 250 #endif /* BTRFS_SPACE_INFO_H */