diff options
Diffstat (limited to 'fs/btrfs/qgroup.h')
| -rw-r--r-- | fs/btrfs/qgroup.h | 64 |
1 files changed, 58 insertions, 6 deletions
diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h index 1bc64c864b62..416ae8e1d23c 100644 --- a/fs/btrfs/qgroup.h +++ b/fs/btrfs/qgroup.h @@ -23,6 +23,34 @@ #include "delayed-ref.h" /* + * Btrfs qgroup overview + * + * Btrfs qgroup splits into 3 main part: + * 1) Reserve + * Reserve metadata/data space for incoming operations + * Affect how qgroup limit works + * + * 2) Trace + * Tell btrfs qgroup to trace dirty extents. + * + * Dirty extents including: + * - Newly allocated extents + * - Extents going to be deleted (in this trans) + * - Extents whose owner is going to be modified + * + * This is the main part affects whether qgroup numbers will stay + * consistent. + * Btrfs qgroup can trace clean extents and won't cause any problem, + * but it will consume extra CPU time, it should be avoided if possible. + * + * 3) Account + * Btrfs qgroup will updates its numbers, based on dirty extents traced + * in previous step. + * + * Normally at qgroup rescan and transaction commit time. + */ + +/* * Record a dirty extent, and info qgroup to update quota on it * TODO: Use kmem cache to alloc it. */ @@ -65,8 +93,8 @@ struct btrfs_delayed_extent_op; int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info); /* - * Insert one dirty extent record into @delayed_refs, informing qgroup to - * account that extent at commit trans time. + * Inform qgroup to trace one dirty extent, its info is recorded in @record. + * So qgroup can account it at commit trans time. * * No lock version, caller must acquire delayed ref lock and allocate memory. * @@ -74,14 +102,15 @@ int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans, * Return >0 for existing record, caller can free @record safely. * Error is not possible */ -int btrfs_qgroup_insert_dirty_extent_nolock( +int btrfs_qgroup_trace_extent_nolock( struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_root *delayed_refs, struct btrfs_qgroup_extent_record *record); /* - * Insert one dirty extent record into @delayed_refs, informing qgroup to - * account that extent at commit trans time. + * Inform qgroup to trace one dirty extent, specified by @bytenr and + * @num_bytes. + * So qgroup can account it at commit trans time. * * Better encapsulated version. * @@ -89,10 +118,33 @@ int btrfs_qgroup_insert_dirty_extent_nolock( * Return <0 for error, like memory allocation failure or invalid parameter * (NULL trans) */ -int btrfs_qgroup_insert_dirty_extent(struct btrfs_trans_handle *trans, +int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr, u64 num_bytes, gfp_t gfp_flag); +/* + * Inform qgroup to trace all leaf items of data + * + * Return 0 for success + * Return <0 for error(ENOMEM) + */ +int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct extent_buffer *eb); +/* + * Inform qgroup to trace a whole subtree, including all its child tree + * blocks and data. + * The root tree block is specified by @root_eb. + * + * Normally used by relocation(tree block swap) and subvolume deletion. + * + * Return 0 for success + * Return <0 for error(ENOMEM or tree search error) + */ +int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *root_eb, + u64 root_gen, int root_level); int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, |