linux-stable/fs/btrfs/block-rsv.h
David Sterba 8bfc9b2cf4 btrfs: use enum for btrfs_block_rsv::type
The number of block group reserve types BTRFS_BLOCK_RSV_* is small and
fits to u8 and there's enough left in case we want to add more.
For type safety use the enum but make it 8 bits in the structure to save
space.

The structure size is now 48 on release build, making a slight
improvement in structures where it's embedded, like btrfs_fs_info or
btrfs_inode.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:40 +02:00

95 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BTRFS_BLOCK_RSV_H
#define BTRFS_BLOCK_RSV_H
struct btrfs_trans_handle;
enum btrfs_reserve_flush_enum;
/*
* Types of block reserves
*/
enum btrfs_rsv_type {
BTRFS_BLOCK_RSV_GLOBAL,
BTRFS_BLOCK_RSV_DELALLOC,
BTRFS_BLOCK_RSV_TRANS,
BTRFS_BLOCK_RSV_CHUNK,
BTRFS_BLOCK_RSV_DELOPS,
BTRFS_BLOCK_RSV_DELREFS,
BTRFS_BLOCK_RSV_EMPTY,
BTRFS_BLOCK_RSV_TEMP,
};
struct btrfs_block_rsv {
u64 size;
u64 reserved;
struct btrfs_space_info *space_info;
spinlock_t lock;
bool full;
bool failfast;
/* Block reserve type, one of BTRFS_BLOCK_RSV_* */
enum btrfs_rsv_type type:8;
/*
* Qgroup equivalent for @size @reserved
*
* Unlike normal @size/@reserved for inode rsv, qgroup doesn't care
* about things like csum size nor how many tree blocks it will need to
* reserve.
*
* Qgroup cares more about net change of the extent usage.
*
* So for one newly inserted file extent, in worst case it will cause
* leaf split and level increase, nodesize for each file extent is
* already too much.
*
* In short, qgroup_size/reserved is the upper limit of possible needed
* qgroup metadata reservation.
*/
u64 qgroup_rsv_size;
u64 qgroup_rsv_reserved;
};
void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, enum btrfs_rsv_type type);
void btrfs_init_root_block_rsv(struct btrfs_root *root);
struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
enum btrfs_rsv_type type);
void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *rsv,
enum btrfs_rsv_type type);
void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *rsv);
int btrfs_block_rsv_add(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *block_rsv, u64 num_bytes,
enum btrfs_reserve_flush_enum flush);
int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor);
int btrfs_block_rsv_refill(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *block_rsv, u64 min_reserved,
enum btrfs_reserve_flush_enum flush);
int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
struct btrfs_block_rsv *dst_rsv, u64 num_bytes,
bool update_size);
int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, u64 num_bytes);
int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *dest, u64 num_bytes,
int min_factor);
void btrfs_block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
u64 num_bytes, bool update_size);
u64 btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *block_rsv,
u64 num_bytes, u64 *qgroup_to_release);
void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info);
void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info);
void btrfs_release_global_block_rsv(struct btrfs_fs_info *fs_info);
struct btrfs_block_rsv *btrfs_use_block_rsv(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u32 blocksize);
static inline void btrfs_unuse_block_rsv(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *block_rsv,
u32 blocksize)
{
btrfs_block_rsv_add_bytes(block_rsv, blocksize, false);
btrfs_block_rsv_release(fs_info, block_rsv, 0, NULL);
}
#endif /* BTRFS_BLOCK_RSV_H */