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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /fs/btrfs/delayed-ref.h | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/btrfs/delayed-ref.h')
-rw-r--r-- | fs/btrfs/delayed-ref.h | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h new file mode 100644 index 0000000000..fd9bf2b709 --- /dev/null +++ b/fs/btrfs/delayed-ref.h @@ -0,0 +1,428 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2008 Oracle. All rights reserved. + */ + +#ifndef BTRFS_DELAYED_REF_H +#define BTRFS_DELAYED_REF_H + +#include <linux/refcount.h> + +/* these are the possible values of struct btrfs_delayed_ref_node->action */ +#define BTRFS_ADD_DELAYED_REF 1 /* add one backref to the tree */ +#define BTRFS_DROP_DELAYED_REF 2 /* delete one backref from the tree */ +#define BTRFS_ADD_DELAYED_EXTENT 3 /* record a full extent allocation */ +#define BTRFS_UPDATE_DELAYED_HEAD 4 /* not changing ref count on head ref */ + +struct btrfs_delayed_ref_node { + struct rb_node ref_node; + /* + * If action is BTRFS_ADD_DELAYED_REF, also link this node to + * ref_head->ref_add_list, then we do not need to iterate the + * whole ref_head->ref_list to find BTRFS_ADD_DELAYED_REF nodes. + */ + struct list_head add_list; + + /* the starting bytenr of the extent */ + u64 bytenr; + + /* the size of the extent */ + u64 num_bytes; + + /* seq number to keep track of insertion order */ + u64 seq; + + /* ref count on this data structure */ + refcount_t refs; + + /* + * how many refs is this entry adding or deleting. For + * head refs, this may be a negative number because it is keeping + * track of the total mods done to the reference count. + * For individual refs, this will always be a positive number + * + * It may be more than one, since it is possible for a single + * parent to have more than one ref on an extent + */ + int ref_mod; + + unsigned int action:8; + unsigned int type:8; +}; + +struct btrfs_delayed_extent_op { + struct btrfs_disk_key key; + u8 level; + bool update_key; + bool update_flags; + u64 flags_to_set; +}; + +/* + * the head refs are used to hold a lock on a given extent, which allows us + * to make sure that only one process is running the delayed refs + * at a time for a single extent. They also store the sum of all the + * reference count modifications we've queued up. + */ +struct btrfs_delayed_ref_head { + u64 bytenr; + u64 num_bytes; + /* + * For insertion into struct btrfs_delayed_ref_root::href_root. + * Keep it in the same cache line as 'bytenr' for more efficient + * searches in the rbtree. + */ + struct rb_node href_node; + /* + * the mutex is held while running the refs, and it is also + * held when checking the sum of reference modifications. + */ + struct mutex mutex; + + refcount_t refs; + + /* Protects 'ref_tree' and 'ref_add_list'. */ + spinlock_t lock; + struct rb_root_cached ref_tree; + /* accumulate add BTRFS_ADD_DELAYED_REF nodes to this ref_add_list. */ + struct list_head ref_add_list; + + struct btrfs_delayed_extent_op *extent_op; + + /* + * This is used to track the final ref_mod from all the refs associated + * with this head ref, this is not adjusted as delayed refs are run, + * this is meant to track if we need to do the csum accounting or not. + */ + int total_ref_mod; + + /* + * This is the current outstanding mod references for this bytenr. This + * is used with lookup_extent_info to get an accurate reference count + * for a bytenr, so it is adjusted as delayed refs are run so that any + * on disk reference count + ref_mod is accurate. + */ + int ref_mod; + + /* + * when a new extent is allocated, it is just reserved in memory + * The actual extent isn't inserted into the extent allocation tree + * until the delayed ref is processed. must_insert_reserved is + * used to flag a delayed ref so the accounting can be updated + * when a full insert is done. + * + * It is possible the extent will be freed before it is ever + * inserted into the extent allocation tree. In this case + * we need to update the in ram accounting to properly reflect + * the free has happened. + */ + bool must_insert_reserved; + bool is_data; + bool is_system; + bool processing; +}; + +struct btrfs_delayed_tree_ref { + struct btrfs_delayed_ref_node node; + u64 root; + u64 parent; + int level; +}; + +struct btrfs_delayed_data_ref { + struct btrfs_delayed_ref_node node; + u64 root; + u64 parent; + u64 objectid; + u64 offset; +}; + +enum btrfs_delayed_ref_flags { + /* Indicate that we are flushing delayed refs for the commit */ + BTRFS_DELAYED_REFS_FLUSHING, +}; + +struct btrfs_delayed_ref_root { + /* head ref rbtree */ + struct rb_root_cached href_root; + + /* dirty extent records */ + struct rb_root dirty_extent_root; + + /* this spin lock protects the rbtree and the entries inside */ + spinlock_t lock; + + /* how many delayed ref updates we've queued, used by the + * throttling code + */ + atomic_t num_entries; + + /* total number of head nodes in tree */ + unsigned long num_heads; + + /* total number of head nodes ready for processing */ + unsigned long num_heads_ready; + + u64 pending_csums; + + unsigned long flags; + + u64 run_delayed_start; + + /* + * To make qgroup to skip given root. + * This is for snapshot, as btrfs_qgroup_inherit() will manually + * modify counters for snapshot and its source, so we should skip + * the snapshot in new_root/old_roots or it will get calculated twice + */ + u64 qgroup_to_skip; +}; + +enum btrfs_ref_type { + BTRFS_REF_NOT_SET, + BTRFS_REF_DATA, + BTRFS_REF_METADATA, + BTRFS_REF_LAST, +}; + +struct btrfs_data_ref { + /* For EXTENT_DATA_REF */ + + /* Original root this data extent belongs to */ + u64 owning_root; + + /* Inode which refers to this data extent */ + u64 ino; + + /* + * file_offset - extent_offset + * + * file_offset is the key.offset of the EXTENT_DATA key. + * extent_offset is btrfs_file_extent_offset() of the EXTENT_DATA data. + */ + u64 offset; +}; + +struct btrfs_tree_ref { + /* + * Level of this tree block + * + * Shared for skinny (TREE_BLOCK_REF) and normal tree ref. + */ + int level; + + /* + * Root which owns this tree block. + * + * For TREE_BLOCK_REF (skinny metadata, either inline or keyed) + */ + u64 owning_root; + + /* For non-skinny metadata, no special member needed */ +}; + +struct btrfs_ref { + enum btrfs_ref_type type; + int action; + + /* + * Whether this extent should go through qgroup record. + * + * Normally false, but for certain cases like delayed subtree scan, + * setting this flag can hugely reduce qgroup overhead. + */ + bool skip_qgroup; + +#ifdef CONFIG_BTRFS_FS_REF_VERIFY + /* Through which root is this modification. */ + u64 real_root; +#endif + u64 bytenr; + u64 len; + + /* Bytenr of the parent tree block */ + u64 parent; + union { + struct btrfs_data_ref data_ref; + struct btrfs_tree_ref tree_ref; + }; +}; + +extern struct kmem_cache *btrfs_delayed_ref_head_cachep; +extern struct kmem_cache *btrfs_delayed_tree_ref_cachep; +extern struct kmem_cache *btrfs_delayed_data_ref_cachep; +extern struct kmem_cache *btrfs_delayed_extent_op_cachep; + +int __init btrfs_delayed_ref_init(void); +void __cold btrfs_delayed_ref_exit(void); + +static inline u64 btrfs_calc_delayed_ref_bytes(const struct btrfs_fs_info *fs_info, + int num_delayed_refs) +{ + u64 num_bytes; + + num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_delayed_refs); + + /* + * We have to check the mount option here because we could be enabling + * the free space tree for the first time and don't have the compat_ro + * option set yet. + * + * We need extra reservations if we have the free space tree because + * we'll have to modify that tree as well. + */ + if (btrfs_test_opt(fs_info, FREE_SPACE_TREE)) + num_bytes *= 2; + + return num_bytes; +} + +static inline void btrfs_init_generic_ref(struct btrfs_ref *generic_ref, + int action, u64 bytenr, u64 len, u64 parent) +{ + generic_ref->action = action; + generic_ref->bytenr = bytenr; + generic_ref->len = len; + generic_ref->parent = parent; +} + +static inline void btrfs_init_tree_ref(struct btrfs_ref *generic_ref, + int level, u64 root, u64 mod_root, bool skip_qgroup) +{ +#ifdef CONFIG_BTRFS_FS_REF_VERIFY + /* If @real_root not set, use @root as fallback */ + generic_ref->real_root = mod_root ?: root; +#endif + generic_ref->tree_ref.level = level; + generic_ref->tree_ref.owning_root = root; + generic_ref->type = BTRFS_REF_METADATA; + if (skip_qgroup || !(is_fstree(root) && + (!mod_root || is_fstree(mod_root)))) + generic_ref->skip_qgroup = true; + else + generic_ref->skip_qgroup = false; + +} + +static inline void btrfs_init_data_ref(struct btrfs_ref *generic_ref, + u64 ref_root, u64 ino, u64 offset, u64 mod_root, + bool skip_qgroup) +{ +#ifdef CONFIG_BTRFS_FS_REF_VERIFY + /* If @real_root not set, use @root as fallback */ + generic_ref->real_root = mod_root ?: ref_root; +#endif + generic_ref->data_ref.owning_root = ref_root; + generic_ref->data_ref.ino = ino; + generic_ref->data_ref.offset = offset; + generic_ref->type = BTRFS_REF_DATA; + if (skip_qgroup || !(is_fstree(ref_root) && + (!mod_root || is_fstree(mod_root)))) + generic_ref->skip_qgroup = true; + else + generic_ref->skip_qgroup = false; +} + +static inline struct btrfs_delayed_extent_op * +btrfs_alloc_delayed_extent_op(void) +{ + return kmem_cache_alloc(btrfs_delayed_extent_op_cachep, GFP_NOFS); +} + +static inline void +btrfs_free_delayed_extent_op(struct btrfs_delayed_extent_op *op) +{ + if (op) + kmem_cache_free(btrfs_delayed_extent_op_cachep, op); +} + +static inline void btrfs_put_delayed_ref(struct btrfs_delayed_ref_node *ref) +{ + WARN_ON(refcount_read(&ref->refs) == 0); + if (refcount_dec_and_test(&ref->refs)) { + WARN_ON(!RB_EMPTY_NODE(&ref->ref_node)); + switch (ref->type) { + case BTRFS_TREE_BLOCK_REF_KEY: + case BTRFS_SHARED_BLOCK_REF_KEY: + kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref); + break; + case BTRFS_EXTENT_DATA_REF_KEY: + case BTRFS_SHARED_DATA_REF_KEY: + kmem_cache_free(btrfs_delayed_data_ref_cachep, ref); + break; + default: + BUG(); + } + } +} + +static inline u64 btrfs_ref_head_to_space_flags( + struct btrfs_delayed_ref_head *head_ref) +{ + if (head_ref->is_data) + return BTRFS_BLOCK_GROUP_DATA; + else if (head_ref->is_system) + return BTRFS_BLOCK_GROUP_SYSTEM; + return BTRFS_BLOCK_GROUP_METADATA; +} + +static inline void btrfs_put_delayed_ref_head(struct btrfs_delayed_ref_head *head) +{ + if (refcount_dec_and_test(&head->refs)) + kmem_cache_free(btrfs_delayed_ref_head_cachep, head); +} + +int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans, + struct btrfs_ref *generic_ref, + struct btrfs_delayed_extent_op *extent_op); +int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans, + struct btrfs_ref *generic_ref, + u64 reserved); +int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans, + u64 bytenr, u64 num_bytes, + struct btrfs_delayed_extent_op *extent_op); +void btrfs_merge_delayed_refs(struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head); + +struct btrfs_delayed_ref_head * +btrfs_find_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs, + u64 bytenr); +int btrfs_delayed_ref_lock(struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head); +static inline void btrfs_delayed_ref_unlock(struct btrfs_delayed_ref_head *head) +{ + mutex_unlock(&head->mutex); +} +void btrfs_delete_ref_head(struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head); + +struct btrfs_delayed_ref_head *btrfs_select_ref_head( + struct btrfs_delayed_ref_root *delayed_refs); + +int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq); + +void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr); +void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans); +int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info, + enum btrfs_reserve_flush_enum flush); +void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info, + u64 num_bytes); +bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info); + +/* + * helper functions to cast a node into its container + */ +static inline struct btrfs_delayed_tree_ref * +btrfs_delayed_node_to_tree_ref(struct btrfs_delayed_ref_node *node) +{ + return container_of(node, struct btrfs_delayed_tree_ref, node); +} + +static inline struct btrfs_delayed_data_ref * +btrfs_delayed_node_to_data_ref(struct btrfs_delayed_ref_node *node) +{ + return container_of(node, struct btrfs_delayed_data_ref, node); +} + +#endif |