diff options
Diffstat (limited to 'fs/btrfs/block-group.h')
| -rw-r--r-- | fs/btrfs/block-group.h | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h new file mode 100644 index 000000000000..054745007519 --- /dev/null +++ b/fs/btrfs/block-group.h @@ -0,0 +1,154 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef BTRFS_BLOCK_GROUP_H +#define BTRFS_BLOCK_GROUP_H + +enum btrfs_disk_cache_state { + BTRFS_DC_WRITTEN, + BTRFS_DC_ERROR, + BTRFS_DC_CLEAR, + BTRFS_DC_SETUP, +}; + +struct btrfs_caching_control { + struct list_head list; + struct mutex mutex; + wait_queue_head_t wait; + struct btrfs_work work; + struct btrfs_block_group_cache *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_cache { + struct btrfs_key key; + struct btrfs_block_group_item item; + struct btrfs_fs_info *fs_info; + struct inode *inode; + spinlock_t lock; + u64 pinned; + u64 reserved; + 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; + + 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; + + /* Usage count */ + atomic_t count; + + /* + * 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; + + atomic_t trimming; + + /* 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; + + /* Record locked full stripes for RAID5/6 block group */ + struct btrfs_full_stripe_locks_tree full_stripe_locks_root; +}; + +#ifdef CONFIG_BTRFS_DEBUG +static inline int btrfs_should_fragment_free_space( + struct btrfs_block_group_cache *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 + +#endif /* BTRFS_BLOCK_GROUP_H */ |