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