linux/fs/btrfs/block-rsv.h
David Sterba 428c8e0310 btrfs: simplify percent calculation helpers, rename div_factor
The div_factor* helpers calculate fraction or percentage fraction. The
name is a bit confusing, we use it only for percentage calculations and
there are two helpers.

There's a helper mult_frac that's for general fractions, that tries to
be accurate but we multiply and divide by small numbers so we can use
the div_u64 helper.

Rename the div_factor* helpers and use 1..100 percentage range, also drop
the case checking for percentage == 100, it's never hit.

The conversions:

* div_factor calculates tenths and the numbers need to be adjusted
* div_factor_fine is direct replacement

Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:48 +01:00

103 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;
struct btrfs_root;
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_percent);
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);
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);
}
/*
* Fast path to check if the reserve is full, may be carefully used outside of
* locks.
*/
static inline bool btrfs_block_rsv_full(const struct btrfs_block_rsv *rsv)
{
return data_race(rsv->full);
}
#endif /* BTRFS_BLOCK_RSV_H */