fs/btrfs/block-rsv.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef BTRFS_BLOCK_RSV_H
   4 #define BTRFS_BLOCK_RSV_H
   5
   6 #include <linux/types.h>
   7 #include <linux/compiler.h>
   8 #include <linux/spinlock.h>
   9
  10 struct btrfs_trans_handle;
  11 struct btrfs_root;
  12 struct btrfs_space_info;
  13 struct btrfs_block_rsv;
  14 struct btrfs_fs_info;
  15 enum btrfs_reserve_flush_enum;
  16
  17 /*
  18  * Types of block reserves
  19  */
  20 enum btrfs_rsv_type {
  21         BTRFS_BLOCK_RSV_GLOBAL,
  22         BTRFS_BLOCK_RSV_DELALLOC,
  23         BTRFS_BLOCK_RSV_TRANS,
  24         BTRFS_BLOCK_RSV_CHUNK,
  25         BTRFS_BLOCK_RSV_DELOPS,
  26         BTRFS_BLOCK_RSV_DELREFS,
  27         BTRFS_BLOCK_RSV_EMPTY,
  28         BTRFS_BLOCK_RSV_TEMP,
  29 };
  30
  31 struct btrfs_block_rsv {
  32         u64 size;
  33         u64 reserved;
  34         struct btrfs_space_info *space_info;
  35         spinlock_t lock;
  36         bool full;
  37         bool failfast;
  38         /* Block reserve type, one of BTRFS_BLOCK_RSV_* */
  39         enum btrfs_rsv_type type:8;
  40
  41         /*
  42          * Qgroup equivalent for @size @reserved
  43          *
  44          * Unlike normal @size/@reserved for inode rsv, qgroup doesn't care
  45          * about things like csum size nor how many tree blocks it will need to
  46          * reserve.
  47          *
  48          * Qgroup cares more about net change of the extent usage.
  49          *
  50          * So for one newly inserted file extent, in worst case it will cause
  51          * leaf split and level increase, nodesize for each file extent is
  52          * already too much.
  53          *
  54          * In short, qgroup_size/reserved is the upper limit of possible needed
  55          * qgroup metadata reservation.
  56          */
  57         u64 qgroup_rsv_size;
  58         u64 qgroup_rsv_reserved;
  59 };
  60
  61 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, enum btrfs_rsv_type type);
  62 void btrfs_init_root_block_rsv(struct btrfs_root *root);
  63 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
  64                                               enum btrfs_rsv_type type);
  65 void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
  66                                    struct btrfs_block_rsv *rsv,
  67                                    enum btrfs_rsv_type type);
  68 void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
  69                           struct btrfs_block_rsv *rsv);
  70 int btrfs_block_rsv_add(struct btrfs_fs_info *fs_info,
  71                         struct btrfs_block_rsv *block_rsv, u64 num_bytes,
  72                         enum btrfs_reserve_flush_enum flush);
  73 int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_percent);
  74 int btrfs_block_rsv_refill(struct btrfs_fs_info *fs_info,
  75                            struct btrfs_block_rsv *block_rsv, u64 num_bytes,
  76                            enum btrfs_reserve_flush_enum flush);
  77 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
  78                             struct btrfs_block_rsv *dst_rsv, u64 num_bytes,
  79                             bool update_size);
  80 int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, u64 num_bytes);
  81 void btrfs_block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
  82                                u64 num_bytes, bool update_size);
  83 u64 btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
  84                               struct btrfs_block_rsv *block_rsv,
  85                               u64 num_bytes, u64 *qgroup_to_release);
  86 void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info);
  87 void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info);
  88 void btrfs_release_global_block_rsv(struct btrfs_fs_info *fs_info);
  89 struct btrfs_block_rsv *btrfs_use_block_rsv(struct btrfs_trans_handle *trans,
  90                                             struct btrfs_root *root,
  91                                             u32 blocksize);
  92 int btrfs_check_trunc_cache_free_space(const struct btrfs_fs_info *fs_info,
  93                                        struct btrfs_block_rsv *rsv);
  94 static inline void btrfs_unuse_block_rsv(struct btrfs_fs_info *fs_info,
  95                                          struct btrfs_block_rsv *block_rsv,
  96                                          u32 blocksize)
  97 {
  98         btrfs_block_rsv_add_bytes(block_rsv, blocksize, false);
  99         btrfs_block_rsv_release(fs_info, block_rsv, 0, NULL);
 100 }
 101
 102 /*
 103  * Fast path to check if the reserve is full, may be carefully used outside of
 104  * locks.
 105  */
 106 static inline bool btrfs_block_rsv_full(const struct btrfs_block_rsv *rsv)
 107 {
 108         return data_race(rsv->full);
 109 }
 110
 111 /*
 112  * Get the reserved mount of a block reserve in a context where getting a stale
 113  * value is acceptable, instead of accessing it directly and trigger data race
 114  * warning from KCSAN.
 115  */
 116 static inline u64 btrfs_block_rsv_reserved(struct btrfs_block_rsv *rsv)
 117 {
 118         u64 ret;
 119
 120         spin_lock(&rsv->lock);
 121         ret = rsv->reserved;
 122         spin_unlock(&rsv->lock);
 123
 124         return ret;
 125 }
 126
 127 /*
 128  * Get the size of a block reserve in a context where getting a stale value is
 129  * acceptable, instead of accessing it directly and trigger data race warning
 130  * from KCSAN.
 131  */
 132 static inline u64 btrfs_block_rsv_size(struct btrfs_block_rsv *rsv)
 133 {
 134         u64 ret;
 135
 136         spin_lock(&rsv->lock);
 137         ret = rsv->size;
 138         spin_unlock(&rsv->lock);
 139
 140         return ret;
 141 }
 142
 143 #endif /* BTRFS_BLOCK_RSV_H */