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