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diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
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+/* 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