blob: 706640be0ec24a3073bec9689e8cedd218cce83e [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
* Copyright (C) 2014 Facebook. All rights reserved.
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/rbtree.h>
#include <linux/kobject.h>
#include <linux/list.h>
#include <uapi/linux/btrfs_tree.h>
struct extent_buffer;
struct extent_changeset;
struct btrfs_delayed_extent_op;
struct btrfs_fs_info;
struct btrfs_root;
struct btrfs_ioctl_quota_ctl_args;
struct btrfs_trans_handle;
struct btrfs_delayed_ref_root;
struct btrfs_inode;
* 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.
* Special performance optimization for balance.
* For balance, we need to swap subtree of subvolume and reloc trees.
* In theory, we need to trace all subtree blocks of both subvolume and reloc
* trees, since their owner has changed during such swap.
* However since balance has ensured that both subtrees are containing the
* same contents and have the same tree structures, such swap won't cause
* qgroup number change.
* But there is a race window between subtree swap and transaction commit,
* during that window, if we increase/decrease tree level or merge/split tree
* blocks, we still need to trace the original subtrees.
* So for balance, we use a delayed subtree tracing, whose workflow is:
* 1) Record the subtree root block get swapped.
* During subtree swap:
* O = Old tree blocks
* N = New tree blocks
* reloc tree subvolume tree X
* Root Root
* / \ / \
* / | | \ / | | \
* In this case, NA and OA are going to be swapped, record (NA, OA) into
* subvolume tree X.
* 2) After subtree swap.
* reloc tree subvolume tree X
* Root Root
* / \ / \
* / | | \ / | | \
* 3a) COW happens for OB
* If we are going to COW tree block OB, we check OB's bytenr against
* tree X's swapped_blocks structure.
* If it doesn't fit any, nothing will happen.
* 3b) COW happens for NA
* Check NA's bytenr against tree X's swapped_blocks, and get a hit.
* Then we do subtree scan on both subtrees OA and NA.
* Resulting 6 tree blocks to be scanned (OA, OC, OD, NA, NC, ND).
* Then no matter what we do to subvolume tree X, qgroup numbers will
* still be correct.
* Then NA's record gets removed from X's swapped_blocks.
* 4) Transaction commit
* Any record in X's swapped_blocks gets removed, since there is no
* modification to the swapped subtrees, no need to trigger heavy qgroup
* subtree rescan for them.
* These flags share the flags field of the btrfs_qgroup_status_item with the
* persisted flags defined in btrfs_tree.h.
* To minimize the chance of collision with new persisted status flags, these
* count backwards from the MSB.
* 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;
* For qgroup reserved data space freeing.
* @data_rsv_refroot and @data_rsv will be recorded after
* And will be used to free reserved qgroup space at
* transaction commit time.
u32 data_rsv; /* reserved data space needs to be freed */
u64 data_rsv_refroot; /* which root the reserved data belongs to */
struct ulist *old_roots;
struct btrfs_qgroup_swapped_block {
struct rb_node node;
int level;
bool trace_leaf;
/* bytenr/generation of the tree block in subvolume tree after swap */
u64 subvol_bytenr;
u64 subvol_generation;
/* bytenr/generation of the tree block in reloc tree after swap */
u64 reloc_bytenr;
u64 reloc_generation;
u64 last_snapshot;
struct btrfs_key first_key;
* Qgroup reservation types:
* space reserved for data
* 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.
* 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 {
* 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 transaction.
* TODO: Add new type for reservation which can survive transaction commit.
* Current metadata reservation behavior is not suitable for such case.
struct btrfs_qgroup_rsv {
* 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 */
* For qgroup iteration usage.
* The iteration list should always be empty until qgroup_iterator_add()
* is called. And should be reset to empty after the iteration is
* finished.
struct list_head iterator;
* For nested iterator usage.
* Here we support at most one level of nested iterator calls like:
* LIST_HEAD(all_qgroups);
* {
* LIST_HEAD(local_qgroups);
* qgroup_iterator_add(local_qgroups, qg);
* qgroup_iterator_nested_add(all_qgroups, qg);
* do_some_work(local_qgroups);
* qgroup_iterator_clean(local_qgroups);
* }
* do_some_work(all_qgroups);
* qgroup_iterator_nested_clean(all_qgroups);
struct list_head nested_iterator;
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;
* Sysfs kobjectid
struct kobject kobj;
struct btrfs_squota_delta {
/* The fstree root this delta counts against. */
u64 root;
/* The number of bytes in the extent being counted. */
u64 num_bytes;
/* The generation the extent was created in. */
u64 generation;
/* Whether we are using or freeing the extent. */
bool is_inc;
/* Whether the extent is data or metadata. */
bool is_data;
static inline u64 btrfs_qgroup_subvolid(u64 qgroupid)
return (qgroupid & ((1ULL << BTRFS_QGROUP_LEVEL_SHIFT) - 1));
* For qgroup event trace points only
enum {
enum btrfs_qgroup_mode {
enum btrfs_qgroup_mode btrfs_qgroup_mode(struct btrfs_fs_info *fs_info);
bool btrfs_qgroup_enabled(struct btrfs_fs_info *fs_info);
bool btrfs_qgroup_full_accounting(struct btrfs_fs_info *fs_info);
int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
struct btrfs_ioctl_quota_ctl_args *quota_ctl_args);
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);
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);
int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans,
struct btrfs_qgroup_extent_record *qrecord);
int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
u64 num_bytes);
int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
struct extent_buffer *eb);
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_check_inherit(struct btrfs_fs_info *fs_info,
struct btrfs_qgroup_inherit *inherit,
size_t size);
int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
u64 objectid, u64 inode_rootid,
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);
int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
u64 rfer, u64 excl);
/* New io_tree based accurate qgroup reserve API */
int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
struct extent_changeset **reserved, u64 start, u64 len);
int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released);
int btrfs_qgroup_free_data(struct btrfs_inode *inode,
struct extent_changeset *reserved, u64 start,
u64 len, u64 *freed);
int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
enum btrfs_qgroup_rsv_type type, bool enforce);
int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
enum btrfs_qgroup_rsv_type type, bool enforce,
bool noflush);
/* 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,
enforce, false);
static inline int btrfs_qgroup_reserve_meta_prealloc(struct btrfs_root *root,
int num_bytes, bool enforce,
bool noflush)
return __btrfs_qgroup_reserve_meta(root, num_bytes,
enforce, noflush);
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,
/* 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,
void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root);
void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes);
void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode);
/* btrfs_qgroup_swapped_blocks related functions */
void btrfs_qgroup_init_swapped_blocks(
struct btrfs_qgroup_swapped_blocks *swapped_blocks);
void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root);
int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
struct btrfs_root *subvol_root,
struct btrfs_block_group *bg,
struct extent_buffer *subvol_parent, int subvol_slot,
struct extent_buffer *reloc_parent, int reloc_slot,
u64 last_snapshot);
int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *eb);
void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans);
bool btrfs_check_quota_leak(struct btrfs_fs_info *fs_info);
void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes);
int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
struct btrfs_squota_delta *delta);