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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BTRFS_SPACE_INFO_H
#define BTRFS_SPACE_INFO_H
#include "volumes.h"
/*
* Different levels for to flush space when doing space reservations.
*
* The higher the level, the more methods we try to reclaim space.
*/
enum btrfs_reserve_flush_enum {
/* If we are in the transaction, we can't flush anything.*/
BTRFS_RESERVE_NO_FLUSH,
/*
* Flush space by:
* - Running delayed inode items
* - Allocating a new chunk
*/
BTRFS_RESERVE_FLUSH_LIMIT,
/*
* Flush space by:
* - Running delayed inode items
* - Running delayed refs
* - Running delalloc and waiting for ordered extents
* - Allocating a new chunk
* - Committing transaction
*/
BTRFS_RESERVE_FLUSH_EVICT,
/*
* Flush space by above mentioned methods and by:
* - Running delayed iputs
* - Committing transaction
*
* Can be interrupted by a fatal signal.
*/
BTRFS_RESERVE_FLUSH_DATA,
BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
BTRFS_RESERVE_FLUSH_ALL,
/*
* Pretty much the same as FLUSH_ALL, but can also steal space from
* global rsv.
*
* Can be interrupted by a fatal signal.
*/
BTRFS_RESERVE_FLUSH_ALL_STEAL,
/*
* This is for btrfs_use_block_rsv only. We have exhausted our block
* rsv and our global block rsv. This can happen for things like
* delalloc where we are overwriting a lot of extents with a single
* extent and didn't reserve enough space. Alternatively it can happen
* with delalloc where we reserve 1 extents worth for a large extent but
* fragmentation leads to multiple extents being created. This will
* give us the reservation in the case of
*
* if (num_bytes < (space_info->total_bytes -
* btrfs_space_info_used(space_info, false))
*
* Which ignores bytes_may_use. This is potentially dangerous, but our
* reservation system is generally pessimistic so is able to absorb this
* style of mistake.
*/
BTRFS_RESERVE_FLUSH_EMERGENCY,
};
enum btrfs_flush_state {
FLUSH_DELAYED_ITEMS_NR = 1,
FLUSH_DELAYED_ITEMS = 2,
FLUSH_DELAYED_REFS_NR = 3,
FLUSH_DELAYED_REFS = 4,
FLUSH_DELALLOC = 5,
FLUSH_DELALLOC_WAIT = 6,
FLUSH_DELALLOC_FULL = 7,
ALLOC_CHUNK = 8,
ALLOC_CHUNK_FORCE = 9,
RUN_DELAYED_IPUTS = 10,
COMMIT_TRANS = 11,
};
struct btrfs_space_info {
spinlock_t lock;
u64 total_bytes; /* total bytes in the space,
this doesn't take mirrors into account */
u64 bytes_used; /* total bytes used,
this doesn't take mirrors into account */
u64 bytes_pinned; /* total bytes pinned, will be freed when the
transaction finishes */
u64 bytes_reserved; /* total bytes the allocator has reserved for
current allocations */
u64 bytes_may_use; /* number of bytes that may be used for
delalloc/allocations */
u64 bytes_readonly; /* total bytes that are read only */
u64 bytes_zone_unusable; /* total bytes that are unusable until
resetting the device zone */
u64 max_extent_size; /* This will hold the maximum extent size of
the space info if we had an ENOSPC in the
allocator. */
/* Chunk size in bytes */
u64 chunk_size;
/*
* Once a block group drops below this threshold (percents) we'll
* schedule it for reclaim.
*/
int bg_reclaim_threshold;
int clamp; /* Used to scale our threshold for preemptive
flushing. The value is >> clamp, so turns
out to be a 2^clamp divisor. */
unsigned int full:1; /* indicates that we cannot allocate any more
chunks for this space */
unsigned int chunk_alloc:1; /* set if we are allocating a chunk */
unsigned int flush:1; /* set if we are trying to make space */
unsigned int force_alloc; /* set if we need to force a chunk
alloc for this space */
u64 disk_used; /* total bytes used on disk */
u64 disk_total; /* total bytes on disk, takes mirrors into
account */
u64 flags;
struct list_head list;
/* Protected by the spinlock 'lock'. */
struct list_head ro_bgs;
struct list_head priority_tickets;
struct list_head tickets;
/*
* Size of space that needs to be reclaimed in order to satisfy pending
* tickets
*/
u64 reclaim_size;
/*
* tickets_id just indicates the next ticket will be handled, so note
* it's not stored per ticket.
*/
u64 tickets_id;
struct rw_semaphore groups_sem;
/* for block groups in our same type */
struct list_head block_groups[BTRFS_NR_RAID_TYPES];
struct kobject kobj;
struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
};
struct reserve_ticket {
u64 bytes;
int error;
bool steal;
struct list_head list;
wait_queue_head_t wait;
};
static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
{
return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
}
/*
*
* Declare a helper function to detect underflow of various space info members
*/
#define DECLARE_SPACE_INFO_UPDATE(name, trace_name) \
static inline void \
btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info, \
struct btrfs_space_info *sinfo, \
s64 bytes) \
{ \
const u64 abs_bytes = (bytes < 0) ? -bytes : bytes; \
lockdep_assert_held(&sinfo->lock); \
trace_update_##name(fs_info, sinfo, sinfo->name, bytes); \
trace_btrfs_space_reservation(fs_info, trace_name, \
sinfo->flags, abs_bytes, \
bytes > 0); \
if (bytes < 0 && sinfo->name < -bytes) { \
WARN_ON(1); \
sinfo->name = 0; \
return; \
} \
sinfo->name += bytes; \
}
DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
struct btrfs_block_group *block_group);
void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
u64 chunk_size);
struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
u64 flags);
u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
bool may_use_included);
void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
struct btrfs_space_info *info, u64 bytes,
int dump_block_groups);
int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
struct btrfs_block_rsv *block_rsv,
u64 orig_bytes,
enum btrfs_reserve_flush_enum flush);
void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
struct btrfs_space_info *space_info);
int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
struct btrfs_space_info *space_info, u64 bytes,
enum btrfs_reserve_flush_enum flush);
static inline void btrfs_space_info_free_bytes_may_use(
struct btrfs_fs_info *fs_info,
struct btrfs_space_info *space_info,
u64 num_bytes)
{
spin_lock(&space_info->lock);
btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
btrfs_try_granting_tickets(fs_info, space_info);
spin_unlock(&space_info->lock);
}
int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
enum btrfs_reserve_flush_enum flush);
void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
#endif /* BTRFS_SPACE_INFO_H */
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