diff options
Diffstat (limited to 'fs/btrfs/qgroup.h')
| -rw-r--r-- | fs/btrfs/qgroup.h | 322 |
1 files changed, 322 insertions, 0 deletions
diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h new file mode 100644 index 000000000..4bbcc1e92 --- /dev/null +++ b/fs/btrfs/qgroup.h @@ -0,0 +1,322 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2014 Facebook. All rights reserved. + */ + +#ifndef BTRFS_QGROUP_H +#define BTRFS_QGROUP_H + +#include "ulist.h" +#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. + */ +struct btrfs_qgroup_extent_record { + struct rb_node node; + u64 bytenr; + u64 num_bytes; + struct ulist *old_roots; +}; + +/* + * Qgroup reservation types: + * + * DATA: + * space reserved for data + * + * META_PERTRANS: + * Space reserved for metadata (per-transaction) + * Due to the fact that qgroup data is only updated at transaction commit + * time, reserved space for metadata must be kept until transaction + * commits. + * Any metadata reserved that are used in btrfs_start_transaction() should + * be of this type. + * + * META_PREALLOC: + * There are cases where metadata space is reserved before starting + * transaction, and then btrfs_join_transaction() to get a trans handle. + * Any metadata reserved for such usage should be of this type. + * And after join_transaction() part (or all) of such reservation should + * be converted into META_PERTRANS. + */ +enum btrfs_qgroup_rsv_type { + BTRFS_QGROUP_RSV_DATA = 0, + BTRFS_QGROUP_RSV_META_PERTRANS, + BTRFS_QGROUP_RSV_META_PREALLOC, + BTRFS_QGROUP_RSV_LAST, +}; + +/* + * Represents how many bytes we have reserved for this qgroup. + * + * Each type should have different reservation behavior. + * E.g, data follows its io_tree flag modification, while + * *currently* meta is just reserve-and-clear during transcation. + * + * TODO: Add new type for reservation which can survive transaction commit. + * Currect metadata reservation behavior is not suitable for such case. + */ +struct btrfs_qgroup_rsv { + u64 values[BTRFS_QGROUP_RSV_LAST]; +}; + +/* + * one struct for each qgroup, organized in fs_info->qgroup_tree. + */ +struct btrfs_qgroup { + u64 qgroupid; + + /* + * state + */ + u64 rfer; /* referenced */ + u64 rfer_cmpr; /* referenced compressed */ + u64 excl; /* exclusive */ + u64 excl_cmpr; /* exclusive compressed */ + + /* + * limits + */ + u64 lim_flags; /* which limits are set */ + u64 max_rfer; + u64 max_excl; + u64 rsv_rfer; + u64 rsv_excl; + + /* + * reservation tracking + */ + struct btrfs_qgroup_rsv rsv; + + /* + * lists + */ + struct list_head groups; /* groups this group is member of */ + struct list_head members; /* groups that are members of this group */ + struct list_head dirty; /* dirty groups */ + struct rb_node node; /* tree of qgroups */ + + /* + * temp variables for accounting operations + * Refer to qgroup_shared_accounting() for details. + */ + u64 old_refcnt; + u64 new_refcnt; +}; + +/* + * For qgroup event trace points only + */ +#define QGROUP_RESERVE (1<<0) +#define QGROUP_RELEASE (1<<1) +#define QGROUP_FREE (1<<2) + +int btrfs_quota_enable(struct btrfs_fs_info *fs_info); +int btrfs_quota_disable(struct btrfs_fs_info *fs_info); +int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info); +void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info); +int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info, + bool interruptible); +int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, + u64 dst); +int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, + u64 dst); +int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid); +int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid); +int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid, + struct btrfs_qgroup_limit *limit); +int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info); +void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info); +struct btrfs_delayed_extent_op; + +/* + * Inform qgroup to trace one dirty extent, its info is recorded in @record. + * So qgroup can account it at transaction committing time. + * + * No lock version, caller must acquire delayed ref lock and allocated memory, + * then call btrfs_qgroup_trace_extent_post() after exiting lock context. + * + * Return 0 for success insert + * Return >0 for existing record, caller can free @record safely. + * Error is not possible + */ +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); + +/* + * Post handler after qgroup_trace_extent_nolock(). + * + * NOTE: Current qgroup does the expensive backref walk at transaction + * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming + * new transaction. + * This is designed to allow btrfs_find_all_roots() to get correct new_roots + * result. + * + * However for old_roots there is no need to do backref walk at that time, + * since we search commit roots to walk backref and result will always be + * correct. + * + * Due to the nature of no lock version, we can't do backref there. + * So we must call btrfs_qgroup_trace_extent_post() after exiting + * spinlock context. + * + * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result + * using current root, then we can move all expensive backref walk out of + * transaction committing, but not now as qgroup accounting will be wrong again. + */ +int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info, + struct btrfs_qgroup_extent_record *qrecord); + +/* + * 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, with memory allocation and backref walk for + * commit roots. + * So this can sleep. + * + * Return 0 if the operation is done. + * Return <0 for error, like memory allocation failure or invalid parameter + * (NULL trans) + */ +int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, 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 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 extent_buffer *root_eb, + u64 root_gen, int root_level); +int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr, + u64 num_bytes, struct ulist *old_roots, + struct ulist *new_roots); +int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans); +int btrfs_run_qgroups(struct btrfs_trans_handle *trans); +int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, + u64 objectid, struct btrfs_qgroup_inherit *inherit); +void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info, + u64 ref_root, u64 num_bytes, + enum btrfs_qgroup_rsv_type type); +static inline void btrfs_qgroup_free_delayed_ref(struct btrfs_fs_info *fs_info, + u64 ref_root, u64 num_bytes) +{ + if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) + return; + trace_btrfs_qgroup_free_delayed_ref(fs_info, ref_root, num_bytes); + btrfs_qgroup_free_refroot(fs_info, ref_root, num_bytes, + BTRFS_QGROUP_RSV_DATA); +} + +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS +int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid, + u64 rfer, u64 excl); +#endif + +/* New io_tree based accurate qgroup reserve API */ +int btrfs_qgroup_reserve_data(struct inode *inode, + struct extent_changeset **reserved, u64 start, u64 len); +int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len); +int btrfs_qgroup_free_data(struct inode *inode, + struct extent_changeset *reserved, u64 start, u64 len); + +int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, + enum btrfs_qgroup_rsv_type type, bool enforce); +/* Reserve metadata space for pertrans and prealloc type */ +static inline int btrfs_qgroup_reserve_meta_pertrans(struct btrfs_root *root, + int num_bytes, bool enforce) +{ + return __btrfs_qgroup_reserve_meta(root, num_bytes, + BTRFS_QGROUP_RSV_META_PERTRANS, enforce); +} +static inline int btrfs_qgroup_reserve_meta_prealloc(struct btrfs_root *root, + int num_bytes, bool enforce) +{ + return __btrfs_qgroup_reserve_meta(root, num_bytes, + BTRFS_QGROUP_RSV_META_PREALLOC, enforce); +} + +void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes, + enum btrfs_qgroup_rsv_type type); + +/* Free per-transaction meta reservation for error handling */ +static inline void btrfs_qgroup_free_meta_pertrans(struct btrfs_root *root, + int num_bytes) +{ + __btrfs_qgroup_free_meta(root, num_bytes, + BTRFS_QGROUP_RSV_META_PERTRANS); +} + +/* Pre-allocated meta reservation can be freed at need */ +static inline void btrfs_qgroup_free_meta_prealloc(struct btrfs_root *root, + int num_bytes) +{ + __btrfs_qgroup_free_meta(root, num_bytes, + BTRFS_QGROUP_RSV_META_PREALLOC); +} + +/* + * Per-transaction meta reservation should be all freed at transaction commit + * time + */ +void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root); + +/* + * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS. + * + * This is called when preallocated meta reservation needs to be used. + * Normally after btrfs_join_transaction() call. + */ +void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes); + +void btrfs_qgroup_check_reserved_leak(struct inode *inode); + +#endif |