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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BTRFS_BLOCK_GROUP_H
#define BTRFS_BLOCK_GROUP_H
#include "free-space-cache.h"
enum btrfs_disk_cache_state {
BTRFS_DC_WRITTEN,
BTRFS_DC_ERROR,
BTRFS_DC_CLEAR,
BTRFS_DC_SETUP,
};
/*
* This describes the state of the block_group for async discard. This is due
* to the two pass nature of it where extent discarding is prioritized over
* bitmap discarding. BTRFS_DISCARD_RESET_CURSOR is set when we are resetting
* between lists to prevent contention for discard state variables
* (eg. discard_cursor).
*/
enum btrfs_discard_state {
BTRFS_DISCARD_EXTENTS,
BTRFS_DISCARD_BITMAPS,
BTRFS_DISCARD_RESET_CURSOR,
};
/*
* Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to
* only allocate a chunk if we really need one.
*
* CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few
* chunks already allocated. This is used as part of the clustering code to
* help make sure we have a good pool of storage to cluster in, without filling
* the FS with empty chunks
*
* CHUNK_ALLOC_FORCE means it must try to allocate one
*/
enum btrfs_chunk_alloc_enum {
CHUNK_ALLOC_NO_FORCE,
CHUNK_ALLOC_LIMITED,
CHUNK_ALLOC_FORCE,
};
struct btrfs_caching_control {
struct list_head list;
struct mutex mutex;
wait_queue_head_t wait;
struct btrfs_work work;
struct btrfs_block_group *block_group;
u64 progress;
refcount_t count;
};
/* Once caching_thread() finds this much free space, it will wake up waiters. */
#define CACHING_CTL_WAKE_UP SZ_2M
struct btrfs_block_group {
struct btrfs_fs_info *fs_info;
struct inode *inode;
spinlock_t lock;
u64 start;
u64 length;
u64 pinned;
u64 reserved;
u64 used;
u64 delalloc_bytes;
u64 bytes_super;
u64 flags;
u64 cache_generation;
/*
* If the free space extent count exceeds this number, convert the block
* group to bitmaps.
*/
u32 bitmap_high_thresh;
/*
* If the free space extent count drops below this number, convert the
* block group back to extents.
*/
u32 bitmap_low_thresh;
/*
* It is just used for the delayed data space allocation because
* only the data space allocation and the relative metadata update
* can be done cross the transaction.
*/
struct rw_semaphore data_rwsem;
/* For raid56, this is a full stripe, without parity */
unsigned long full_stripe_len;
unsigned int ro;
unsigned int iref:1;
unsigned int has_caching_ctl:1;
unsigned int removed:1;
unsigned int to_copy:1;
unsigned int relocating_repair:1;
unsigned int chunk_item_inserted:1;
unsigned int zone_is_active:1;
int disk_cache_state;
/* Cache tracking stuff */
int cached;
struct btrfs_caching_control *caching_ctl;
u64 last_byte_to_unpin;
struct btrfs_space_info *space_info;
/* Free space cache stuff */
struct btrfs_free_space_ctl *free_space_ctl;
/* Block group cache stuff */
struct rb_node cache_node;
/* For block groups in the same raid type */
struct list_head list;
refcount_t refs;
/*
* List of struct btrfs_free_clusters for this block group.
* Today it will only have one thing on it, but that may change
*/
struct list_head cluster_list;
/* For delayed block group creation or deletion of empty block groups */
struct list_head bg_list;
/* For read-only block groups */
struct list_head ro_list;
/*
* When non-zero it means the block group's logical address and its
* device extents can not be reused for future block group allocations
* until the counter goes down to 0. This is to prevent them from being
* reused while some task is still using the block group after it was
* deleted - we want to make sure they can only be reused for new block
* groups after that task is done with the deleted block group.
*/
atomic_t frozen;
/* For discard operations */
struct list_head discard_list;
int discard_index;
u64 discard_eligible_time;
u64 discard_cursor;
enum btrfs_discard_state discard_state;
/* For dirty block groups */
struct list_head dirty_list;
struct list_head io_list;
struct btrfs_io_ctl io_ctl;
/*
* Incremented when doing extent allocations and holding a read lock
* on the space_info's groups_sem semaphore.
* Decremented when an ordered extent that represents an IO against this
* block group's range is created (after it's added to its inode's
* root's list of ordered extents) or immediately after the allocation
* if it's a metadata extent or fallocate extent (for these cases we
* don't create ordered extents).
*/
atomic_t reservations;
/*
* Incremented while holding the spinlock *lock* by a task checking if
* it can perform a nocow write (incremented if the value for the *ro*
* field is 0). Decremented by such tasks once they create an ordered
* extent or before that if some error happens before reaching that step.
* This is to prevent races between block group relocation and nocow
* writes through direct IO.
*/
atomic_t nocow_writers;
/* Lock for free space tree operations. */
struct mutex free_space_lock;
/*
* Does the block group need to be added to the free space tree?
* Protected by free_space_lock.
*/
int needs_free_space;
/* Flag indicating this block group is placed on a sequential zone */
bool seq_zone;
/*
* Number of extents in this block group used for swap files.
* All accesses protected by the spinlock 'lock'.
*/
int swap_extents;
/* Record locked full stripes for RAID5/6 block group */
struct btrfs_full_stripe_locks_tree full_stripe_locks_root;
/*
* Allocation offset for the block group to implement sequential
* allocation. This is used only on a zoned filesystem.
*/
u64 alloc_offset;
u64 zone_unusable;
u64 zone_capacity;
u64 meta_write_pointer;
struct map_lookup *physical_map;
struct list_head active_bg_list;
};
static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group)
{
return (block_group->start + block_group->length);
}
static inline bool btrfs_is_block_group_data_only(
struct btrfs_block_group *block_group)
{
/*
* In mixed mode the fragmentation is expected to be high, lowering the
* efficiency, so only proper data block groups are considered.
*/
return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) &&
!(block_group->flags & BTRFS_BLOCK_GROUP_METADATA);
}
#ifdef CONFIG_BTRFS_DEBUG
static inline int btrfs_should_fragment_free_space(
struct btrfs_block_group *block_group)
{
struct btrfs_fs_info *fs_info = block_group->fs_info;
return (btrfs_test_opt(fs_info, FRAGMENT_METADATA) &&
block_group->flags & BTRFS_BLOCK_GROUP_METADATA) ||
(btrfs_test_opt(fs_info, FRAGMENT_DATA) &&
block_group->flags & BTRFS_BLOCK_GROUP_DATA);
}
#endif
struct btrfs_block_group *btrfs_lookup_first_block_group(
struct btrfs_fs_info *info, u64 bytenr);
struct btrfs_block_group *btrfs_lookup_block_group(
struct btrfs_fs_info *info, u64 bytenr);
struct btrfs_block_group *btrfs_next_block_group(
struct btrfs_block_group *cache);
void btrfs_get_block_group(struct btrfs_block_group *cache);
void btrfs_put_block_group(struct btrfs_block_group *cache);
void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
const u64 start);
void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg);
bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
void btrfs_wait_nocow_writers(struct btrfs_block_group *bg);
void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache,
u64 num_bytes);
int btrfs_wait_block_group_cache_done(struct btrfs_block_group *cache);
int btrfs_cache_block_group(struct btrfs_block_group *cache,
int load_cache_only);
void btrfs_put_caching_control(struct btrfs_caching_control *ctl);
struct btrfs_caching_control *btrfs_get_caching_control(
struct btrfs_block_group *cache);
u64 add_new_free_space(struct btrfs_block_group *block_group,
u64 start, u64 end);
struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
struct btrfs_fs_info *fs_info,
const u64 chunk_offset);
int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
u64 group_start, struct extent_map *em);
void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
void btrfs_mark_bg_unused(struct btrfs_block_group *bg);
void btrfs_reclaim_bgs_work(struct work_struct *work);
void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info);
void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg);
int btrfs_read_block_groups(struct btrfs_fs_info *info);
struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans,
u64 bytes_used, u64 type,
u64 chunk_offset, u64 size);
void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
int btrfs_inc_block_group_ro(struct btrfs_block_group *cache,
bool do_chunk_alloc);
void btrfs_dec_block_group_ro(struct btrfs_block_group *cache);
int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
int btrfs_update_block_group(struct btrfs_trans_handle *trans,
u64 bytenr, u64 num_bytes, int alloc);
int btrfs_add_reserved_bytes(struct btrfs_block_group *cache,
u64 ram_bytes, u64 num_bytes, int delalloc);
void btrfs_free_reserved_bytes(struct btrfs_block_group *cache,
u64 num_bytes, int delalloc);
int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
enum btrfs_chunk_alloc_enum force);
int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
int btrfs_free_block_groups(struct btrfs_fs_info *info);
void btrfs_wait_space_cache_v1_finished(struct btrfs_block_group *cache,
struct btrfs_caching_control *caching_ctl);
int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
struct block_device *bdev, u64 physical, u64 **logical,
int *naddrs, int *stripe_len);
static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
{
return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
}
static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
{
return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
}
static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
{
return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
}
static inline int btrfs_block_group_done(struct btrfs_block_group *cache)
{
smp_mb();
return cache->cached == BTRFS_CACHE_FINISHED ||
cache->cached == BTRFS_CACHE_ERROR;
}
void btrfs_freeze_block_group(struct btrfs_block_group *cache);
void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);
bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg);
void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount);
#endif /* BTRFS_BLOCK_GROUP_H */
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