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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Copyright (C) 2007 Oracle.  All rights reserved.4 */5 6#ifndef BTRFS_CTREE_H7#define BTRFS_CTREE_H8 9#include "linux/cleanup.h"10#include <linux/pagemap.h>11#include <linux/spinlock.h>12#include <linux/rbtree.h>13#include <linux/mutex.h>14#include <linux/wait.h>15#include <linux/list.h>16#include <linux/atomic.h>17#include <linux/xarray.h>18#include <linux/refcount.h>19#include <uapi/linux/btrfs_tree.h>20#include "locking.h"21#include "fs.h"22#include "accessors.h"23#include "extent-io-tree.h"24 25struct extent_buffer;26struct btrfs_block_rsv;27struct btrfs_trans_handle;28struct btrfs_block_group;29 30/* Read ahead values for struct btrfs_path.reada */31enum {32	READA_NONE,33	READA_BACK,34	READA_FORWARD,35	/*36	 * Similar to READA_FORWARD but unlike it:37	 *38	 * 1) It will trigger readahead even for leaves that are not close to39	 *    each other on disk;40	 * 2) It also triggers readahead for nodes;41	 * 3) During a search, even when a node or leaf is already in memory, it42	 *    will still trigger readahead for other nodes and leaves that follow43	 *    it.44	 *45	 * This is meant to be used only when we know we are iterating over the46	 * entire tree or a very large part of it.47	 */48	READA_FORWARD_ALWAYS,49};50 51/*52 * btrfs_paths remember the path taken from the root down to the leaf.53 * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point54 * to any other levels that are present.55 *56 * The slots array records the index of the item or block pointer57 * used while walking the tree.58 */59struct btrfs_path {60	struct extent_buffer *nodes[BTRFS_MAX_LEVEL];61	int slots[BTRFS_MAX_LEVEL];62	/* if there is real range locking, this locks field will change */63	u8 locks[BTRFS_MAX_LEVEL];64	u8 reada;65	/* keep some upper locks as we walk down */66	u8 lowest_level;67 68	/*69	 * set by btrfs_split_item, tells search_slot to keep all locks70	 * and to force calls to keep space in the nodes71	 */72	unsigned int search_for_split:1;73	unsigned int keep_locks:1;74	unsigned int skip_locking:1;75	unsigned int search_commit_root:1;76	unsigned int need_commit_sem:1;77	unsigned int skip_release_on_error:1;78	/*79	 * Indicate that new item (btrfs_search_slot) is extending already80	 * existing item and ins_len contains only the data size and not item81	 * header (ie. sizeof(struct btrfs_item) is not included).82	 */83	unsigned int search_for_extension:1;84	/* Stop search if any locks need to be taken (for read) */85	unsigned int nowait:1;86};87 88#define BTRFS_PATH_AUTO_FREE(path_name)					\89	struct btrfs_path *path_name __free(btrfs_free_path) = NULL90 91/*92 * The state of btrfs root93 */94enum {95	/*96	 * btrfs_record_root_in_trans is a multi-step process, and it can race97	 * with the balancing code.   But the race is very small, and only the98	 * first time the root is added to each transaction.  So IN_TRANS_SETUP99	 * is used to tell us when more checks are required100	 */101	BTRFS_ROOT_IN_TRANS_SETUP,102 103	/*104	 * Set if tree blocks of this root can be shared by other roots.105	 * Only subvolume trees and their reloc trees have this bit set.106	 * Conflicts with TRACK_DIRTY bit.107	 *108	 * This affects two things:109	 *110	 * - How balance works111	 *   For shareable roots, we need to use reloc tree and do path112	 *   replacement for balance, and need various pre/post hooks for113	 *   snapshot creation to handle them.114	 *115	 *   While for non-shareable trees, we just simply do a tree search116	 *   with COW.117	 *118	 * - How dirty roots are tracked119	 *   For shareable roots, btrfs_record_root_in_trans() is needed to120	 *   track them, while non-subvolume roots have TRACK_DIRTY bit, they121	 *   don't need to set this manually.122	 */123	BTRFS_ROOT_SHAREABLE,124	BTRFS_ROOT_TRACK_DIRTY,125	BTRFS_ROOT_IN_RADIX,126	BTRFS_ROOT_ORPHAN_ITEM_INSERTED,127	BTRFS_ROOT_DEFRAG_RUNNING,128	BTRFS_ROOT_FORCE_COW,129	BTRFS_ROOT_MULTI_LOG_TASKS,130	BTRFS_ROOT_DIRTY,131	BTRFS_ROOT_DELETING,132 133	/*134	 * Reloc tree is orphan, only kept here for qgroup delayed subtree scan135	 *136	 * Set for the subvolume tree owning the reloc tree.137	 */138	BTRFS_ROOT_DEAD_RELOC_TREE,139	/* Mark dead root stored on device whose cleanup needs to be resumed */140	BTRFS_ROOT_DEAD_TREE,141	/* The root has a log tree. Used for subvolume roots and the tree root. */142	BTRFS_ROOT_HAS_LOG_TREE,143	/* Qgroup flushing is in progress */144	BTRFS_ROOT_QGROUP_FLUSHING,145	/* We started the orphan cleanup for this root. */146	BTRFS_ROOT_ORPHAN_CLEANUP,147	/* This root has a drop operation that was started previously. */148	BTRFS_ROOT_UNFINISHED_DROP,149	/* This reloc root needs to have its buffers lockdep class reset. */150	BTRFS_ROOT_RESET_LOCKDEP_CLASS,151};152 153/*154 * Record swapped tree blocks of a subvolume tree for delayed subtree trace155 * code. For detail check comment in fs/btrfs/qgroup.c.156 */157struct btrfs_qgroup_swapped_blocks {158	spinlock_t lock;159	/* RM_EMPTY_ROOT() of above blocks[] */160	bool swapped;161	struct rb_root blocks[BTRFS_MAX_LEVEL];162};163 164/*165 * in ram representation of the tree.  extent_root is used for all allocations166 * and for the extent tree extent_root root.167 */168struct btrfs_root {169	struct rb_node rb_node;170 171	struct extent_buffer *node;172 173	struct extent_buffer *commit_root;174	struct btrfs_root *log_root;175	struct btrfs_root *reloc_root;176 177	unsigned long state;178	struct btrfs_root_item root_item;179	struct btrfs_key root_key;180	struct btrfs_fs_info *fs_info;181	struct extent_io_tree dirty_log_pages;182 183	struct mutex objectid_mutex;184 185	spinlock_t accounting_lock;186	struct btrfs_block_rsv *block_rsv;187 188	struct mutex log_mutex;189	wait_queue_head_t log_writer_wait;190	wait_queue_head_t log_commit_wait[2];191	struct list_head log_ctxs[2];192	/* Used only for log trees of subvolumes, not for the log root tree */193	atomic_t log_writers;194	atomic_t log_commit[2];195	/* Used only for log trees of subvolumes, not for the log root tree */196	atomic_t log_batch;197	/*198	 * Protected by the 'log_mutex' lock but can be read without holding199	 * that lock to avoid unnecessary lock contention, in which case it200	 * should be read using btrfs_get_root_log_transid() except if it's a201	 * log tree in which case it can be directly accessed. Updates to this202	 * field should always use btrfs_set_root_log_transid(), except for log203	 * trees where the field can be updated directly.204	 */205	int log_transid;206	/* No matter the commit succeeds or not*/207	int log_transid_committed;208	/*209	 * Just be updated when the commit succeeds. Use210	 * btrfs_get_root_last_log_commit() and btrfs_set_root_last_log_commit()211	 * to access this field.212	 */213	int last_log_commit;214	pid_t log_start_pid;215 216	u64 last_trans;217 218	u64 free_objectid;219 220	struct btrfs_key defrag_progress;221	struct btrfs_key defrag_max;222 223	/* The dirty list is only used by non-shareable roots */224	struct list_head dirty_list;225 226	struct list_head root_list;227 228	/*229	 * Xarray that keeps track of in-memory inodes, protected by the lock230	 * @inode_lock.231	 */232	struct xarray inodes;233 234	/*235	 * Xarray that keeps track of delayed nodes of every inode, protected236	 * by @inode_lock.237	 */238	struct xarray delayed_nodes;239	/*240	 * right now this just gets used so that a root has its own devid241	 * for stat.  It may be used for more later242	 */243	dev_t anon_dev;244 245	spinlock_t root_item_lock;246	refcount_t refs;247 248	struct mutex delalloc_mutex;249	spinlock_t delalloc_lock;250	/*251	 * all of the inodes that have delalloc bytes.  It is possible for252	 * this list to be empty even when there is still dirty data=ordered253	 * extents waiting to finish IO.254	 */255	struct list_head delalloc_inodes;256	struct list_head delalloc_root;257	u64 nr_delalloc_inodes;258 259	struct mutex ordered_extent_mutex;260	/*261	 * this is used by the balancing code to wait for all the pending262	 * ordered extents263	 */264	spinlock_t ordered_extent_lock;265 266	/*267	 * all of the data=ordered extents pending writeback268	 * these can span multiple transactions and basically include269	 * every dirty data page that isn't from nodatacow270	 */271	struct list_head ordered_extents;272	struct list_head ordered_root;273	u64 nr_ordered_extents;274 275	/*276	 * Not empty if this subvolume root has gone through tree block swap277	 * (relocation)278	 *279	 * Will be used by reloc_control::dirty_subvol_roots.280	 */281	struct list_head reloc_dirty_list;282 283	/*284	 * Number of currently running SEND ioctls to prevent285	 * manipulation with the read-only status via SUBVOL_SETFLAGS286	 */287	int send_in_progress;288	/*289	 * Number of currently running deduplication operations that have a290	 * destination inode belonging to this root. Protected by the lock291	 * root_item_lock.292	 */293	int dedupe_in_progress;294	/* For exclusion of snapshot creation and nocow writes */295	struct btrfs_drew_lock snapshot_lock;296 297	atomic_t snapshot_force_cow;298 299	/* For qgroup metadata reserved space */300	spinlock_t qgroup_meta_rsv_lock;301	u64 qgroup_meta_rsv_pertrans;302	u64 qgroup_meta_rsv_prealloc;303	wait_queue_head_t qgroup_flush_wait;304 305	/* Number of active swapfiles */306	atomic_t nr_swapfiles;307 308	/* Record pairs of swapped blocks for qgroup */309	struct btrfs_qgroup_swapped_blocks swapped_blocks;310 311	/* Used only by log trees, when logging csum items */312	struct extent_io_tree log_csum_range;313 314	/* Used in simple quotas, track root during relocation. */315	u64 relocation_src_root;316 317#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS318	u64 alloc_bytenr;319#endif320 321#ifdef CONFIG_BTRFS_DEBUG322	struct list_head leak_list;323#endif324};325 326static inline bool btrfs_root_readonly(const struct btrfs_root *root)327{328	/* Byte-swap the constant at compile time, root_item::flags is LE */329	return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_RDONLY)) != 0;330}331 332static inline bool btrfs_root_dead(const struct btrfs_root *root)333{334	/* Byte-swap the constant at compile time, root_item::flags is LE */335	return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_DEAD)) != 0;336}337 338static inline u64 btrfs_root_id(const struct btrfs_root *root)339{340	return root->root_key.objectid;341}342 343static inline int btrfs_get_root_log_transid(const struct btrfs_root *root)344{345	return READ_ONCE(root->log_transid);346}347 348static inline void btrfs_set_root_log_transid(struct btrfs_root *root, int log_transid)349{350	WRITE_ONCE(root->log_transid, log_transid);351}352 353static inline int btrfs_get_root_last_log_commit(const struct btrfs_root *root)354{355	return READ_ONCE(root->last_log_commit);356}357 358static inline void btrfs_set_root_last_log_commit(struct btrfs_root *root, int commit_id)359{360	WRITE_ONCE(root->last_log_commit, commit_id);361}362 363static inline u64 btrfs_get_root_last_trans(const struct btrfs_root *root)364{365	return READ_ONCE(root->last_trans);366}367 368static inline void btrfs_set_root_last_trans(struct btrfs_root *root, u64 transid)369{370	WRITE_ONCE(root->last_trans, transid);371}372 373/*374 * Structure that conveys information about an extent that is going to replace375 * all the extents in a file range.376 */377struct btrfs_replace_extent_info {378	u64 disk_offset;379	u64 disk_len;380	u64 data_offset;381	u64 data_len;382	u64 file_offset;383	/* Pointer to a file extent item of type regular or prealloc. */384	char *extent_buf;385	/*386	 * Set to true when attempting to replace a file range with a new extent387	 * described by this structure, set to false when attempting to clone an388	 * existing extent into a file range.389	 */390	bool is_new_extent;391	/* Indicate if we should update the inode's mtime and ctime. */392	bool update_times;393	/* Meaningful only if is_new_extent is true. */394	int qgroup_reserved;395	/*396	 * Meaningful only if is_new_extent is true.397	 * Used to track how many extent items we have already inserted in a398	 * subvolume tree that refer to the extent described by this structure,399	 * so that we know when to create a new delayed ref or update an existing400	 * one.401	 */402	int insertions;403};404 405/* Arguments for btrfs_drop_extents() */406struct btrfs_drop_extents_args {407	/* Input parameters */408 409	/*410	 * If NULL, btrfs_drop_extents() will allocate and free its own path.411	 * If 'replace_extent' is true, this must not be NULL. Also the path412	 * is always released except if 'replace_extent' is true and413	 * btrfs_drop_extents() sets 'extent_inserted' to true, in which case414	 * the path is kept locked.415	 */416	struct btrfs_path *path;417	/* Start offset of the range to drop extents from */418	u64 start;419	/* End (exclusive, last byte + 1) of the range to drop extents from */420	u64 end;421	/* If true drop all the extent maps in the range */422	bool drop_cache;423	/*424	 * If true it means we want to insert a new extent after dropping all425	 * the extents in the range. If this is true, the 'extent_item_size'426	 * parameter must be set as well and the 'extent_inserted' field will427	 * be set to true by btrfs_drop_extents() if it could insert the new428	 * extent.429	 * Note: when this is set to true the path must not be NULL.430	 */431	bool replace_extent;432	/*433	 * Used if 'replace_extent' is true. Size of the file extent item to434	 * insert after dropping all existing extents in the range435	 */436	u32 extent_item_size;437 438	/* Output parameters */439 440	/*441	 * Set to the minimum between the input parameter 'end' and the end442	 * (exclusive, last byte + 1) of the last dropped extent. This is always443	 * set even if btrfs_drop_extents() returns an error.444	 */445	u64 drop_end;446	/*447	 * The number of allocated bytes found in the range. This can be smaller448	 * than the range's length when there are holes in the range.449	 */450	u64 bytes_found;451	/*452	 * Only set if 'replace_extent' is true. Set to true if we were able453	 * to insert a replacement extent after dropping all extents in the454	 * range, otherwise set to false by btrfs_drop_extents().455	 * Also, if btrfs_drop_extents() has set this to true it means it456	 * returned with the path locked, otherwise if it has set this to457	 * false it has returned with the path released.458	 */459	bool extent_inserted;460};461 462struct btrfs_file_private {463	void *filldir_buf;464	u64 last_index;465	struct extent_state *llseek_cached_state;466	/* Task that allocated this structure. */467	struct task_struct *owner_task;468};469 470static inline u32 BTRFS_LEAF_DATA_SIZE(const struct btrfs_fs_info *info)471{472	return info->nodesize - sizeof(struct btrfs_header);473}474 475static inline u32 BTRFS_MAX_ITEM_SIZE(const struct btrfs_fs_info *info)476{477	return BTRFS_LEAF_DATA_SIZE(info) - sizeof(struct btrfs_item);478}479 480static inline u32 BTRFS_NODEPTRS_PER_BLOCK(const struct btrfs_fs_info *info)481{482	return BTRFS_LEAF_DATA_SIZE(info) / sizeof(struct btrfs_key_ptr);483}484 485static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info)486{487	return BTRFS_MAX_ITEM_SIZE(info) - sizeof(struct btrfs_dir_item);488}489 490#define BTRFS_BYTES_TO_BLKS(fs_info, bytes) \491				((bytes) >> (fs_info)->sectorsize_bits)492 493static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping)494{495	return mapping_gfp_constraint(mapping, ~__GFP_FS);496}497 498void btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info, u64 start, u64 end);499int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,500			 u64 num_bytes, u64 *actual_bytes);501int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range);502 503/* ctree.c */504int __init btrfs_ctree_init(void);505void __cold btrfs_ctree_exit(void);506 507int btrfs_bin_search(struct extent_buffer *eb, int first_slot,508		     const struct btrfs_key *key, int *slot);509 510int __pure btrfs_comp_cpu_keys(const struct btrfs_key *k1, const struct btrfs_key *k2);511 512#ifdef __LITTLE_ENDIAN513 514/*515 * Compare two keys, on little-endian the disk order is same as CPU order and516 * we can avoid the conversion.517 */518static inline int btrfs_comp_keys(const struct btrfs_disk_key *disk_key,519				  const struct btrfs_key *k2)520{521	const struct btrfs_key *k1 = (const struct btrfs_key *)disk_key;522 523	return btrfs_comp_cpu_keys(k1, k2);524}525 526#else527 528/* Compare two keys in a memcmp fashion. */529static inline int btrfs_comp_keys(const struct btrfs_disk_key *disk,530				  const struct btrfs_key *k2)531{532	struct btrfs_key k1;533 534	btrfs_disk_key_to_cpu(&k1, disk);535 536	return btrfs_comp_cpu_keys(&k1, k2);537}538 539#endif540 541int btrfs_previous_item(struct btrfs_root *root,542			struct btrfs_path *path, u64 min_objectid,543			int type);544int btrfs_previous_extent_item(struct btrfs_root *root,545			struct btrfs_path *path, u64 min_objectid);546void btrfs_set_item_key_safe(struct btrfs_trans_handle *trans,547			     const struct btrfs_path *path,548			     const struct btrfs_key *new_key);549struct extent_buffer *btrfs_root_node(struct btrfs_root *root);550int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path,551			struct btrfs_key *key, int lowest_level,552			u64 min_trans);553int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,554			 struct btrfs_path *path,555			 u64 min_trans);556struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent,557					   int slot);558 559int btrfs_cow_block(struct btrfs_trans_handle *trans,560		    struct btrfs_root *root, struct extent_buffer *buf,561		    struct extent_buffer *parent, int parent_slot,562		    struct extent_buffer **cow_ret,563		    enum btrfs_lock_nesting nest);564int btrfs_force_cow_block(struct btrfs_trans_handle *trans,565			  struct btrfs_root *root,566			  struct extent_buffer *buf,567			  struct extent_buffer *parent, int parent_slot,568			  struct extent_buffer **cow_ret,569			  u64 search_start, u64 empty_size,570			  enum btrfs_lock_nesting nest);571int btrfs_copy_root(struct btrfs_trans_handle *trans,572		      struct btrfs_root *root,573		      struct extent_buffer *buf,574		      struct extent_buffer **cow_ret, u64 new_root_objectid);575bool btrfs_block_can_be_shared(struct btrfs_trans_handle *trans,576			       struct btrfs_root *root,577			       struct extent_buffer *buf);578int btrfs_del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,579		  struct btrfs_path *path, int level, int slot);580void btrfs_extend_item(struct btrfs_trans_handle *trans,581		       const struct btrfs_path *path, u32 data_size);582void btrfs_truncate_item(struct btrfs_trans_handle *trans,583			 const struct btrfs_path *path, u32 new_size, int from_end);584int btrfs_split_item(struct btrfs_trans_handle *trans,585		     struct btrfs_root *root,586		     struct btrfs_path *path,587		     const struct btrfs_key *new_key,588		     unsigned long split_offset);589int btrfs_duplicate_item(struct btrfs_trans_handle *trans,590			 struct btrfs_root *root,591			 struct btrfs_path *path,592			 const struct btrfs_key *new_key);593int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *path,594		u64 inum, u64 ioff, u8 key_type, struct btrfs_key *found_key);595int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root,596		      const struct btrfs_key *key, struct btrfs_path *p,597		      int ins_len, int cow);598int btrfs_search_old_slot(struct btrfs_root *root, const struct btrfs_key *key,599			  struct btrfs_path *p, u64 time_seq);600int btrfs_search_slot_for_read(struct btrfs_root *root,601			       const struct btrfs_key *key,602			       struct btrfs_path *p, int find_higher,603			       int return_any);604void btrfs_release_path(struct btrfs_path *p);605struct btrfs_path *btrfs_alloc_path(void);606void btrfs_free_path(struct btrfs_path *p);607DEFINE_FREE(btrfs_free_path, struct btrfs_path *, btrfs_free_path(_T))608 609int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,610		   struct btrfs_path *path, int slot, int nr);611static inline int btrfs_del_item(struct btrfs_trans_handle *trans,612				 struct btrfs_root *root,613				 struct btrfs_path *path)614{615	return btrfs_del_items(trans, root, path, path->slots[0], 1);616}617 618/*619 * Describes a batch of items to insert in a btree. This is used by620 * btrfs_insert_empty_items().621 */622struct btrfs_item_batch {623	/*624	 * Pointer to an array containing the keys of the items to insert (in625	 * sorted order).626	 */627	const struct btrfs_key *keys;628	/* Pointer to an array containing the data size for each item to insert. */629	const u32 *data_sizes;630	/*631	 * The sum of data sizes for all items. The caller can compute this while632	 * setting up the data_sizes array, so it ends up being more efficient633	 * than having btrfs_insert_empty_items() or setup_item_for_insert()634	 * doing it, as it would avoid an extra loop over a potentially large635	 * array, and in the case of setup_item_for_insert(), we would be doing636	 * it while holding a write lock on a leaf and often on upper level nodes637	 * too, unnecessarily increasing the size of a critical section.638	 */639	u32 total_data_size;640	/* Size of the keys and data_sizes arrays (number of items in the batch). */641	int nr;642};643 644void btrfs_setup_item_for_insert(struct btrfs_trans_handle *trans,645				 struct btrfs_root *root,646				 struct btrfs_path *path,647				 const struct btrfs_key *key,648				 u32 data_size);649int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,650		      const struct btrfs_key *key, void *data, u32 data_size);651int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,652			     struct btrfs_root *root,653			     struct btrfs_path *path,654			     const struct btrfs_item_batch *batch);655 656static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,657					  struct btrfs_root *root,658					  struct btrfs_path *path,659					  const struct btrfs_key *key,660					  u32 data_size)661{662	struct btrfs_item_batch batch;663 664	batch.keys = key;665	batch.data_sizes = &data_size;666	batch.total_data_size = data_size;667	batch.nr = 1;668 669	return btrfs_insert_empty_items(trans, root, path, &batch);670}671 672int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path,673			u64 time_seq);674 675int btrfs_search_backwards(struct btrfs_root *root, struct btrfs_key *key,676			   struct btrfs_path *path);677 678int btrfs_get_next_valid_item(struct btrfs_root *root, struct btrfs_key *key,679			      struct btrfs_path *path);680 681/*682 * Search in @root for a given @key, and store the slot found in @found_key.683 *684 * @root:	The root node of the tree.685 * @key:	The key we are looking for.686 * @found_key:	Will hold the found item.687 * @path:	Holds the current slot/leaf.688 * @iter_ret:	Contains the value returned from btrfs_search_slot or689 * 		btrfs_get_next_valid_item, whichever was executed last.690 *691 * The @iter_ret is an output variable that will contain the return value of692 * btrfs_search_slot, if it encountered an error, or the value returned from693 * btrfs_get_next_valid_item otherwise. That return value can be 0, if a valid694 * slot was found, 1 if there were no more leaves, and <0 if there was an error.695 *696 * It's recommended to use a separate variable for iter_ret and then use it to697 * set the function return value so there's no confusion of the 0/1/errno698 * values stemming from btrfs_search_slot.699 */700#define btrfs_for_each_slot(root, key, found_key, path, iter_ret)		\701	for (iter_ret = btrfs_search_slot(NULL, (root), (key), (path), 0, 0);	\702		(iter_ret) >= 0 &&						\703		(iter_ret = btrfs_get_next_valid_item((root), (found_key), (path))) == 0; \704		(path)->slots[0]++						\705	)706 707int btrfs_next_old_item(struct btrfs_root *root, struct btrfs_path *path, u64 time_seq);708 709/*710 * Search the tree again to find a leaf with greater keys.711 *712 * Returns 0 if it found something or 1 if there are no greater leaves.713 * Returns < 0 on error.714 */715static inline int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)716{717	return btrfs_next_old_leaf(root, path, 0);718}719 720static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p)721{722	return btrfs_next_old_item(root, p, 0);723}724int btrfs_leaf_free_space(const struct extent_buffer *leaf);725 726static inline int is_fstree(u64 rootid)727{728	if (rootid == BTRFS_FS_TREE_OBJECTID ||729	    ((s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID &&730	      !btrfs_qgroup_level(rootid)))731		return 1;732	return 0;733}734 735static inline bool btrfs_is_data_reloc_root(const struct btrfs_root *root)736{737	return root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID;738}739 740u16 btrfs_csum_type_size(u16 type);741int btrfs_super_csum_size(const struct btrfs_super_block *s);742const char *btrfs_super_csum_name(u16 csum_type);743const char *btrfs_super_csum_driver(u16 csum_type);744size_t __attribute_const__ btrfs_get_num_csums(void);745 746/*747 * We use page status Private2 to indicate there is an ordered extent with748 * unfinished IO.749 *750 * Rename the Private2 accessors to Ordered, to improve readability.751 */752#define PageOrdered(page)		PagePrivate2(page)753#define SetPageOrdered(page)		SetPagePrivate2(page)754#define ClearPageOrdered(page)		ClearPagePrivate2(page)755#define folio_test_ordered(folio)	folio_test_private_2(folio)756#define folio_set_ordered(folio)	folio_set_private_2(folio)757#define folio_clear_ordered(folio)	folio_clear_private_2(folio)758 759#endif760