linux/fs/btrfs/free-space-cache.h
Boris Burkov 36b216c85e btrfs: remove free space items when disabling space cache v1
When the filesystem transitions from space cache v1 to v2 or to
nospace_cache, it removes the old cached data, but does not remove
the FREE_SPACE items nor the free space inodes they point to. This
doesn't cause any issues besides being a bit inefficient, since these
items no longer do anything useful.

To fix it, when we are mounting, and plan to disable the space cache,
destroy each block group's free space item and free space inode.
The code to remove the items is lifted from the existing use case of
removing the block group, with a light adaptation to handle whether or
not we have already looked up the free space inode.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09 19:16:09 +01:00

151 lines
5.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2009 Oracle. All rights reserved.
*/
#ifndef BTRFS_FREE_SPACE_CACHE_H
#define BTRFS_FREE_SPACE_CACHE_H
/*
* This is the trim state of an extent or bitmap.
*
* BTRFS_TRIM_STATE_TRIMMING is special and used to maintain the state of a
* bitmap as we may need several trims to fully trim a single bitmap entry.
* This is reset should any free space other than trimmed space be added to the
* bitmap.
*/
enum btrfs_trim_state {
BTRFS_TRIM_STATE_UNTRIMMED,
BTRFS_TRIM_STATE_TRIMMED,
BTRFS_TRIM_STATE_TRIMMING,
};
struct btrfs_free_space {
struct rb_node offset_index;
u64 offset;
u64 bytes;
u64 max_extent_size;
unsigned long *bitmap;
struct list_head list;
enum btrfs_trim_state trim_state;
s32 bitmap_extents;
};
static inline bool btrfs_free_space_trimmed(struct btrfs_free_space *info)
{
return (info->trim_state == BTRFS_TRIM_STATE_TRIMMED);
}
static inline bool btrfs_free_space_trimming_bitmap(
struct btrfs_free_space *info)
{
return (info->trim_state == BTRFS_TRIM_STATE_TRIMMING);
}
struct btrfs_free_space_ctl {
spinlock_t tree_lock;
struct rb_root free_space_offset;
u64 free_space;
int extents_thresh;
int free_extents;
int total_bitmaps;
int unit;
u64 start;
s32 discardable_extents[BTRFS_STAT_NR_ENTRIES];
s64 discardable_bytes[BTRFS_STAT_NR_ENTRIES];
const struct btrfs_free_space_op *op;
void *private;
struct mutex cache_writeout_mutex;
struct list_head trimming_ranges;
};
struct btrfs_free_space_op {
bool (*use_bitmap)(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info);
};
struct btrfs_io_ctl {
void *cur, *orig;
struct page *page;
struct page **pages;
struct btrfs_fs_info *fs_info;
struct inode *inode;
unsigned long size;
int index;
int num_pages;
int entries;
int bitmaps;
};
struct inode *lookup_free_space_inode(struct btrfs_block_group *block_group,
struct btrfs_path *path);
int create_free_space_inode(struct btrfs_trans_handle *trans,
struct btrfs_block_group *block_group,
struct btrfs_path *path);
int btrfs_remove_free_space_inode(struct btrfs_trans_handle *trans,
struct inode *inode,
struct btrfs_block_group *block_group);
int btrfs_check_trunc_cache_free_space(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *rsv);
int btrfs_truncate_free_space_cache(struct btrfs_trans_handle *trans,
struct btrfs_block_group *block_group,
struct inode *inode);
int load_free_space_cache(struct btrfs_block_group *block_group);
int btrfs_wait_cache_io(struct btrfs_trans_handle *trans,
struct btrfs_block_group *block_group,
struct btrfs_path *path);
int btrfs_write_out_cache(struct btrfs_trans_handle *trans,
struct btrfs_block_group *block_group,
struct btrfs_path *path);
void btrfs_init_free_space_ctl(struct btrfs_block_group *block_group,
struct btrfs_free_space_ctl *ctl);
int __btrfs_add_free_space(struct btrfs_fs_info *fs_info,
struct btrfs_free_space_ctl *ctl,
u64 bytenr, u64 size,
enum btrfs_trim_state trim_state);
int btrfs_add_free_space(struct btrfs_block_group *block_group,
u64 bytenr, u64 size);
int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group,
u64 bytenr, u64 size);
int btrfs_remove_free_space(struct btrfs_block_group *block_group,
u64 bytenr, u64 size);
void __btrfs_remove_free_space_cache(struct btrfs_free_space_ctl *ctl);
void btrfs_remove_free_space_cache(struct btrfs_block_group *block_group);
bool btrfs_is_free_space_trimmed(struct btrfs_block_group *block_group);
u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group,
u64 offset, u64 bytes, u64 empty_size,
u64 *max_extent_size);
void btrfs_dump_free_space(struct btrfs_block_group *block_group,
u64 bytes);
int btrfs_find_space_cluster(struct btrfs_block_group *block_group,
struct btrfs_free_cluster *cluster,
u64 offset, u64 bytes, u64 empty_size);
void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster);
u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group,
struct btrfs_free_cluster *cluster, u64 bytes,
u64 min_start, u64 *max_extent_size);
void btrfs_return_cluster_to_free_space(
struct btrfs_block_group *block_group,
struct btrfs_free_cluster *cluster);
int btrfs_trim_block_group(struct btrfs_block_group *block_group,
u64 *trimmed, u64 start, u64 end, u64 minlen);
int btrfs_trim_block_group_extents(struct btrfs_block_group *block_group,
u64 *trimmed, u64 start, u64 end, u64 minlen,
bool async);
int btrfs_trim_block_group_bitmaps(struct btrfs_block_group *block_group,
u64 *trimmed, u64 start, u64 end, u64 minlen,
u64 maxlen, bool async);
bool btrfs_free_space_cache_v1_active(struct btrfs_fs_info *fs_info);
int btrfs_set_free_space_cache_v1_active(struct btrfs_fs_info *fs_info, bool active);
/* Support functions for running our sanity tests */
#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
int test_add_free_space_entry(struct btrfs_block_group *cache,
u64 offset, u64 bytes, bool bitmap);
int test_check_exists(struct btrfs_block_group *cache, u64 offset, u64 bytes);
#endif
#endif