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Diffstat (limited to 'fs/btrfs/ctree.h')
| -rw-r--r-- | fs/btrfs/ctree.h | 730 |
1 files changed, 730 insertions, 0 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h new file mode 100644 index 0000000000..06333a74d6 --- /dev/null +++ b/fs/btrfs/ctree.h @@ -0,0 +1,730 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2007 Oracle. All rights reserved. + */ + +#ifndef BTRFS_CTREE_H +#define BTRFS_CTREE_H + +#include <linux/mm.h> +#include <linux/sched/signal.h> +#include <linux/highmem.h> +#include <linux/fs.h> +#include <linux/rwsem.h> +#include <linux/semaphore.h> +#include <linux/completion.h> +#include <linux/backing-dev.h> +#include <linux/wait.h> +#include <linux/slab.h> +#include <trace/events/btrfs.h> +#include <asm/unaligned.h> +#include <linux/pagemap.h> +#include <linux/btrfs.h> +#include <linux/btrfs_tree.h> +#include <linux/workqueue.h> +#include <linux/security.h> +#include <linux/sizes.h> +#include <linux/dynamic_debug.h> +#include <linux/refcount.h> +#include <linux/crc32c.h> +#include <linux/iomap.h> +#include <linux/fscrypt.h> +#include "extent-io-tree.h" +#include "extent_io.h" +#include "extent_map.h" +#include "async-thread.h" +#include "block-rsv.h" +#include "locking.h" +#include "misc.h" +#include "fs.h" + +struct btrfs_trans_handle; +struct btrfs_transaction; +struct btrfs_pending_snapshot; +struct btrfs_delayed_ref_root; +struct btrfs_space_info; +struct btrfs_block_group; +struct btrfs_ordered_sum; +struct btrfs_ref; +struct btrfs_bio; +struct btrfs_ioctl_encoded_io_args; +struct btrfs_device; +struct btrfs_fs_devices; +struct btrfs_balance_control; +struct btrfs_delayed_root; +struct reloc_control; + +/* Read ahead values for struct btrfs_path.reada */ +enum { + READA_NONE, + READA_BACK, + READA_FORWARD, + /* + * Similar to READA_FORWARD but unlike it: + * + * 1) It will trigger readahead even for leaves that are not close to + * each other on disk; + * 2) It also triggers readahead for nodes; + * 3) During a search, even when a node or leaf is already in memory, it + * will still trigger readahead for other nodes and leaves that follow + * it. + * + * This is meant to be used only when we know we are iterating over the + * entire tree or a very large part of it. + */ + READA_FORWARD_ALWAYS, +}; + +/* + * btrfs_paths remember the path taken from the root down to the leaf. + * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point + * to any other levels that are present. + * + * The slots array records the index of the item or block pointer + * used while walking the tree. + */ +struct btrfs_path { + struct extent_buffer *nodes[BTRFS_MAX_LEVEL]; + int slots[BTRFS_MAX_LEVEL]; + /* if there is real range locking, this locks field will change */ + u8 locks[BTRFS_MAX_LEVEL]; + u8 reada; + /* keep some upper locks as we walk down */ + u8 lowest_level; + + /* + * set by btrfs_split_item, tells search_slot to keep all locks + * and to force calls to keep space in the nodes + */ + unsigned int search_for_split:1; + unsigned int keep_locks:1; + unsigned int skip_locking:1; + unsigned int search_commit_root:1; + unsigned int need_commit_sem:1; + unsigned int skip_release_on_error:1; + /* + * Indicate that new item (btrfs_search_slot) is extending already + * existing item and ins_len contains only the data size and not item + * header (ie. sizeof(struct btrfs_item) is not included). + */ + unsigned int search_for_extension:1; + /* Stop search if any locks need to be taken (for read) */ + unsigned int nowait:1; +}; + +/* + * The state of btrfs root + */ +enum { + /* + * btrfs_record_root_in_trans is a multi-step process, and it can race + * with the balancing code. But the race is very small, and only the + * first time the root is added to each transaction. So IN_TRANS_SETUP + * is used to tell us when more checks are required + */ + BTRFS_ROOT_IN_TRANS_SETUP, + + /* + * Set if tree blocks of this root can be shared by other roots. + * Only subvolume trees and their reloc trees have this bit set. + * Conflicts with TRACK_DIRTY bit. + * + * This affects two things: + * + * - How balance works + * For shareable roots, we need to use reloc tree and do path + * replacement for balance, and need various pre/post hooks for + * snapshot creation to handle them. + * + * While for non-shareable trees, we just simply do a tree search + * with COW. + * + * - How dirty roots are tracked + * For shareable roots, btrfs_record_root_in_trans() is needed to + * track them, while non-subvolume roots have TRACK_DIRTY bit, they + * don't need to set this manually. + */ + BTRFS_ROOT_SHAREABLE, + BTRFS_ROOT_TRACK_DIRTY, + BTRFS_ROOT_IN_RADIX, + BTRFS_ROOT_ORPHAN_ITEM_INSERTED, + BTRFS_ROOT_DEFRAG_RUNNING, + BTRFS_ROOT_FORCE_COW, + BTRFS_ROOT_MULTI_LOG_TASKS, + BTRFS_ROOT_DIRTY, + BTRFS_ROOT_DELETING, + + /* + * Reloc tree is orphan, only kept here for qgroup delayed subtree scan + * + * Set for the subvolume tree owning the reloc tree. + */ + BTRFS_ROOT_DEAD_RELOC_TREE, + /* Mark dead root stored on device whose cleanup needs to be resumed */ + BTRFS_ROOT_DEAD_TREE, + /* The root has a log tree. Used for subvolume roots and the tree root. */ + BTRFS_ROOT_HAS_LOG_TREE, + /* Qgroup flushing is in progress */ + BTRFS_ROOT_QGROUP_FLUSHING, + /* We started the orphan cleanup for this root. */ + BTRFS_ROOT_ORPHAN_CLEANUP, + /* This root has a drop operation that was started previously. */ + BTRFS_ROOT_UNFINISHED_DROP, + /* This reloc root needs to have its buffers lockdep class reset. */ + BTRFS_ROOT_RESET_LOCKDEP_CLASS, +}; + +/* + * Record swapped tree blocks of a subvolume tree for delayed subtree trace + * code. For detail check comment in fs/btrfs/qgroup.c. + */ +struct btrfs_qgroup_swapped_blocks { + spinlock_t lock; + /* RM_EMPTY_ROOT() of above blocks[] */ + bool swapped; + struct rb_root blocks[BTRFS_MAX_LEVEL]; +}; + +/* + * in ram representation of the tree. extent_root is used for all allocations + * and for the extent tree extent_root root. + */ +struct btrfs_root { + struct rb_node rb_node; + + struct extent_buffer *node; + + struct extent_buffer *commit_root; + struct btrfs_root *log_root; + struct btrfs_root *reloc_root; + + unsigned long state; + struct btrfs_root_item root_item; + struct btrfs_key root_key; + struct btrfs_fs_info *fs_info; + struct extent_io_tree dirty_log_pages; + + struct mutex objectid_mutex; + + spinlock_t accounting_lock; + struct btrfs_block_rsv *block_rsv; + + struct mutex log_mutex; + wait_queue_head_t log_writer_wait; + wait_queue_head_t log_commit_wait[2]; + struct list_head log_ctxs[2]; + /* Used only for log trees of subvolumes, not for the log root tree */ + atomic_t log_writers; + atomic_t log_commit[2]; + /* Used only for log trees of subvolumes, not for the log root tree */ + atomic_t log_batch; + int log_transid; + /* No matter the commit succeeds or not*/ + int log_transid_committed; + /* Just be updated when the commit succeeds. */ + int last_log_commit; + pid_t log_start_pid; + + u64 last_trans; + + u32 type; + + u64 free_objectid; + + struct btrfs_key defrag_progress; + struct btrfs_key defrag_max; + + /* The dirty list is only used by non-shareable roots */ + struct list_head dirty_list; + + struct list_head root_list; + + spinlock_t log_extents_lock[2]; + struct list_head logged_list[2]; + + spinlock_t inode_lock; + /* red-black tree that keeps track of in-memory inodes */ + struct rb_root inode_tree; + + /* + * radix tree that keeps track of delayed nodes of every inode, + * protected by inode_lock + */ + struct radix_tree_root delayed_nodes_tree; + /* + * right now this just gets used so that a root has its own devid + * for stat. It may be used for more later + */ + dev_t anon_dev; + + spinlock_t root_item_lock; + refcount_t refs; + + struct mutex delalloc_mutex; + spinlock_t delalloc_lock; + /* + * all of the inodes that have delalloc bytes. It is possible for + * this list to be empty even when there is still dirty data=ordered + * extents waiting to finish IO. + */ + struct list_head delalloc_inodes; + struct list_head delalloc_root; + u64 nr_delalloc_inodes; + + struct mutex ordered_extent_mutex; + /* + * this is used by the balancing code to wait for all the pending + * ordered extents + */ + spinlock_t ordered_extent_lock; + + /* + * all of the data=ordered extents pending writeback + * these can span multiple transactions and basically include + * every dirty data page that isn't from nodatacow + */ + struct list_head ordered_extents; + struct list_head ordered_root; + u64 nr_ordered_extents; + + /* + * Not empty if this subvolume root has gone through tree block swap + * (relocation) + * + * Will be used by reloc_control::dirty_subvol_roots. + */ + struct list_head reloc_dirty_list; + + /* + * Number of currently running SEND ioctls to prevent + * manipulation with the read-only status via SUBVOL_SETFLAGS + */ + int send_in_progress; + /* + * Number of currently running deduplication operations that have a + * destination inode belonging to this root. Protected by the lock + * root_item_lock. + */ + int dedupe_in_progress; + /* For exclusion of snapshot creation and nocow writes */ + struct btrfs_drew_lock snapshot_lock; + + atomic_t snapshot_force_cow; + + /* For qgroup metadata reserved space */ + spinlock_t qgroup_meta_rsv_lock; + u64 qgroup_meta_rsv_pertrans; + u64 qgroup_meta_rsv_prealloc; + wait_queue_head_t qgroup_flush_wait; + + /* Number of active swapfiles */ + atomic_t nr_swapfiles; + + /* Record pairs of swapped blocks for qgroup */ + struct btrfs_qgroup_swapped_blocks swapped_blocks; + + /* Used only by log trees, when logging csum items */ + struct extent_io_tree log_csum_range; + +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS + u64 alloc_bytenr; +#endif + +#ifdef CONFIG_BTRFS_DEBUG + struct list_head leak_list; +#endif +}; + +static inline bool btrfs_root_readonly(const struct btrfs_root *root) +{ + /* Byte-swap the constant at compile time, root_item::flags is LE */ + return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_RDONLY)) != 0; +} + +static inline bool btrfs_root_dead(const struct btrfs_root *root) +{ + /* Byte-swap the constant at compile time, root_item::flags is LE */ + return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_DEAD)) != 0; +} + +static inline u64 btrfs_root_id(const struct btrfs_root *root) +{ + return root->root_key.objectid; +} + +/* + * Structure that conveys information about an extent that is going to replace + * all the extents in a file range. + */ +struct btrfs_replace_extent_info { + u64 disk_offset; + u64 disk_len; + u64 data_offset; + u64 data_len; + u64 file_offset; + /* Pointer to a file extent item of type regular or prealloc. */ + char *extent_buf; + /* + * Set to true when attempting to replace a file range with a new extent + * described by this structure, set to false when attempting to clone an + * existing extent into a file range. + */ + bool is_new_extent; + /* Indicate if we should update the inode's mtime and ctime. */ + bool update_times; + /* Meaningful only if is_new_extent is true. */ + int qgroup_reserved; + /* + * Meaningful only if is_new_extent is true. + * Used to track how many extent items we have already inserted in a + * subvolume tree that refer to the extent described by this structure, + * so that we know when to create a new delayed ref or update an existing + * one. + */ + int insertions; +}; + +/* Arguments for btrfs_drop_extents() */ +struct btrfs_drop_extents_args { + /* Input parameters */ + + /* + * If NULL, btrfs_drop_extents() will allocate and free its own path. + * If 'replace_extent' is true, this must not be NULL. Also the path + * is always released except if 'replace_extent' is true and + * btrfs_drop_extents() sets 'extent_inserted' to true, in which case + * the path is kept locked. + */ + struct btrfs_path *path; + /* Start offset of the range to drop extents from */ + u64 start; + /* End (exclusive, last byte + 1) of the range to drop extents from */ + u64 end; + /* If true drop all the extent maps in the range */ + bool drop_cache; + /* + * If true it means we want to insert a new extent after dropping all + * the extents in the range. If this is true, the 'extent_item_size' + * parameter must be set as well and the 'extent_inserted' field will + * be set to true by btrfs_drop_extents() if it could insert the new + * extent. + * Note: when this is set to true the path must not be NULL. + */ + bool replace_extent; + /* + * Used if 'replace_extent' is true. Size of the file extent item to + * insert after dropping all existing extents in the range + */ + u32 extent_item_size; + + /* Output parameters */ + + /* + * Set to the minimum between the input parameter 'end' and the end + * (exclusive, last byte + 1) of the last dropped extent. This is always + * set even if btrfs_drop_extents() returns an error. + */ + u64 drop_end; + /* + * The number of allocated bytes found in the range. This can be smaller + * than the range's length when there are holes in the range. + */ + u64 bytes_found; + /* + * Only set if 'replace_extent' is true. Set to true if we were able + * to insert a replacement extent after dropping all extents in the + * range, otherwise set to false by btrfs_drop_extents(). + * Also, if btrfs_drop_extents() has set this to true it means it + * returned with the path locked, otherwise if it has set this to + * false it has returned with the path released. + */ + bool extent_inserted; +}; + +struct btrfs_file_private { + void *filldir_buf; + u64 last_index; + struct extent_state *llseek_cached_state; +}; + +static inline u32 BTRFS_LEAF_DATA_SIZE(const struct btrfs_fs_info *info) +{ + return info->nodesize - sizeof(struct btrfs_header); +} + +static inline u32 BTRFS_MAX_ITEM_SIZE(const struct btrfs_fs_info *info) +{ + return BTRFS_LEAF_DATA_SIZE(info) - sizeof(struct btrfs_item); +} + +static inline u32 BTRFS_NODEPTRS_PER_BLOCK(const struct btrfs_fs_info *info) +{ + return BTRFS_LEAF_DATA_SIZE(info) / sizeof(struct btrfs_key_ptr); +} + +static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info) +{ + return BTRFS_MAX_ITEM_SIZE(info) - sizeof(struct btrfs_dir_item); +} + +#define BTRFS_BYTES_TO_BLKS(fs_info, bytes) \ + ((bytes) >> (fs_info)->sectorsize_bits) + +static inline u32 btrfs_crc32c(u32 crc, const void *address, unsigned length) +{ + return crc32c(crc, address, length); +} + +static inline void btrfs_crc32c_final(u32 crc, u8 *result) +{ + put_unaligned_le32(~crc, result); +} + +static inline u64 btrfs_name_hash(const char *name, int len) +{ + return crc32c((u32)~1, name, len); +} + +/* + * Figure the key offset of an extended inode ref + */ +static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name, + int len) +{ + return (u64) crc32c(parent_objectid, name, len); +} + +static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping) +{ + return mapping_gfp_constraint(mapping, ~__GFP_FS); +} + +int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info, + u64 start, u64 end); +int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr, + u64 num_bytes, u64 *actual_bytes); +int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range); + +/* ctree.c */ +int __init btrfs_ctree_init(void); +void __cold btrfs_ctree_exit(void); + +int btrfs_bin_search(struct extent_buffer *eb, int first_slot, + const struct btrfs_key *key, int *slot); + +int __pure btrfs_comp_cpu_keys(const struct btrfs_key *k1, const struct btrfs_key *k2); +int btrfs_previous_item(struct btrfs_root *root, + struct btrfs_path *path, u64 min_objectid, + int type); +int btrfs_previous_extent_item(struct btrfs_root *root, + struct btrfs_path *path, u64 min_objectid); +void btrfs_set_item_key_safe(struct btrfs_trans_handle *trans, + struct btrfs_path *path, + const struct btrfs_key *new_key); +struct extent_buffer *btrfs_root_node(struct btrfs_root *root); +int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path, + struct btrfs_key *key, int lowest_level, + u64 min_trans); +int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, + struct btrfs_path *path, + u64 min_trans); +struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent, + int slot); + +int btrfs_cow_block(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct extent_buffer *buf, + struct extent_buffer *parent, int parent_slot, + struct extent_buffer **cow_ret, + enum btrfs_lock_nesting nest); +int btrfs_copy_root(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *buf, + struct extent_buffer **cow_ret, u64 new_root_objectid); +int btrfs_block_can_be_shared(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *buf); +int btrfs_del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, + struct btrfs_path *path, int level, int slot); +void btrfs_extend_item(struct btrfs_trans_handle *trans, + struct btrfs_path *path, u32 data_size); +void btrfs_truncate_item(struct btrfs_trans_handle *trans, + struct btrfs_path *path, u32 new_size, int from_end); +int btrfs_split_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + const struct btrfs_key *new_key, + unsigned long split_offset); +int btrfs_duplicate_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + const struct btrfs_key *new_key); +int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *path, + u64 inum, u64 ioff, u8 key_type, struct btrfs_key *found_key); +int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root, + const struct btrfs_key *key, struct btrfs_path *p, + int ins_len, int cow); +int btrfs_search_old_slot(struct btrfs_root *root, const struct btrfs_key *key, + struct btrfs_path *p, u64 time_seq); +int btrfs_search_slot_for_read(struct btrfs_root *root, + const struct btrfs_key *key, + struct btrfs_path *p, int find_higher, + int return_any); +int btrfs_realloc_node(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct extent_buffer *parent, + int start_slot, u64 *last_ret, + struct btrfs_key *progress); +void btrfs_release_path(struct btrfs_path *p); +struct btrfs_path *btrfs_alloc_path(void); +void btrfs_free_path(struct btrfs_path *p); + +int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, + struct btrfs_path *path, int slot, int nr); +static inline int btrfs_del_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path) +{ + return btrfs_del_items(trans, root, path, path->slots[0], 1); +} + +/* + * Describes a batch of items to insert in a btree. This is used by + * btrfs_insert_empty_items(). + */ +struct btrfs_item_batch { + /* + * Pointer to an array containing the keys of the items to insert (in + * sorted order). + */ + const struct btrfs_key *keys; + /* Pointer to an array containing the data size for each item to insert. */ + const u32 *data_sizes; + /* + * The sum of data sizes for all items. The caller can compute this while + * setting up the data_sizes array, so it ends up being more efficient + * than having btrfs_insert_empty_items() or setup_item_for_insert() + * doing it, as it would avoid an extra loop over a potentially large + * array, and in the case of setup_item_for_insert(), we would be doing + * it while holding a write lock on a leaf and often on upper level nodes + * too, unnecessarily increasing the size of a critical section. + */ + u32 total_data_size; + /* Size of the keys and data_sizes arrays (number of items in the batch). */ + int nr; +}; + +void btrfs_setup_item_for_insert(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + const struct btrfs_key *key, + u32 data_size); +int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, + const struct btrfs_key *key, void *data, u32 data_size); +int btrfs_insert_empty_items(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + const struct btrfs_item_batch *batch); + +static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + const struct btrfs_key *key, + u32 data_size) +{ + struct btrfs_item_batch batch; + + batch.keys = key; + batch.data_sizes = &data_size; + batch.total_data_size = data_size; + batch.nr = 1; + + return btrfs_insert_empty_items(trans, root, path, &batch); +} + +int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path, + u64 time_seq); + +int btrfs_search_backwards(struct btrfs_root *root, struct btrfs_key *key, + struct btrfs_path *path); + +int btrfs_get_next_valid_item(struct btrfs_root *root, struct btrfs_key *key, + struct btrfs_path *path); + +/* + * Search in @root for a given @key, and store the slot found in @found_key. + * + * @root: The root node of the tree. + * @key: The key we are looking for. + * @found_key: Will hold the found item. + * @path: Holds the current slot/leaf. + * @iter_ret: Contains the value returned from btrfs_search_slot or + * btrfs_get_next_valid_item, whichever was executed last. + * + * The @iter_ret is an output variable that will contain the return value of + * btrfs_search_slot, if it encountered an error, or the value returned from + * btrfs_get_next_valid_item otherwise. That return value can be 0, if a valid + * slot was found, 1 if there were no more leaves, and <0 if there was an error. + * + * It's recommended to use a separate variable for iter_ret and then use it to + * set the function return value so there's no confusion of the 0/1/errno + * values stemming from btrfs_search_slot. + */ +#define btrfs_for_each_slot(root, key, found_key, path, iter_ret) \ + for (iter_ret = btrfs_search_slot(NULL, (root), (key), (path), 0, 0); \ + (iter_ret) >= 0 && \ + (iter_ret = btrfs_get_next_valid_item((root), (found_key), (path))) == 0; \ + (path)->slots[0]++ \ + ) + +int btrfs_next_old_item(struct btrfs_root *root, struct btrfs_path *path, u64 time_seq); + +/* + * Search the tree again to find a leaf with greater keys. + * + * Returns 0 if it found something or 1 if there are no greater leaves. + * Returns < 0 on error. + */ +static inline int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) +{ + return btrfs_next_old_leaf(root, path, 0); +} + +static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p) +{ + return btrfs_next_old_item(root, p, 0); +} +int btrfs_leaf_free_space(const struct extent_buffer *leaf); + +static inline int is_fstree(u64 rootid) +{ + if (rootid == BTRFS_FS_TREE_OBJECTID || + ((s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID && + !btrfs_qgroup_level(rootid))) + return 1; + return 0; +} + +static inline bool btrfs_is_data_reloc_root(const struct btrfs_root *root) +{ + return root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID; +} + +u16 btrfs_csum_type_size(u16 type); +int btrfs_super_csum_size(const struct btrfs_super_block *s); +const char *btrfs_super_csum_name(u16 csum_type); +const char *btrfs_super_csum_driver(u16 csum_type); +size_t __attribute_const__ btrfs_get_num_csums(void); + +/* + * We use page status Private2 to indicate there is an ordered extent with + * unfinished IO. + * + * Rename the Private2 accessors to Ordered, to improve readability. + */ +#define PageOrdered(page) PagePrivate2(page) +#define SetPageOrdered(page) SetPagePrivate2(page) +#define ClearPageOrdered(page) ClearPagePrivate2(page) +#define folio_test_ordered(folio) folio_test_private_2(folio) +#define folio_set_ordered(folio) folio_set_private_2(folio) +#define folio_clear_ordered(folio) folio_clear_private_2(folio) + +#endif |