linux/fs/btrfs/ctree.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 */

#ifndef BTRFS_CTREE_H
#define BTRFS_CTREE_H

#include <linux/pagemap.h>
#include <linux/spinlock.h>
#include <linux/rbtree.h>
#include <linux/mutex.h>
#include <linux/wait.h>
#include <linux/list.h>
#include <linux/atomic.h>
#include <linux/xarray.h>
#include <linux/refcount.h>
#include <uapi/linux/btrfs_tree.h>
#include "locking.h"
#include "fs.h"
#include "accessors.h"
#include "extent-io-tree.h"

struct extent_buffer;
struct btrfs_block_rsv;
struct btrfs_trans_handle;
struct btrfs_block_group;

/* Read ahead values for struct btrfs_path.reada */
enum { … };

/*
 * 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 { … };

/*
 * The state of btrfs root
 */
enum { … };

/*
 * 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 { … };

/*
 * in ram representation of the tree.  extent_root is used for all allocations
 * and for the extent tree extent_root root.
 */
struct btrfs_root { … };

static inline bool btrfs_root_readonly(const struct btrfs_root *root)
{ … }

static inline bool btrfs_root_dead(const struct btrfs_root *root)
{ … }

static inline u64 btrfs_root_id(const struct btrfs_root *root)
{ … }

static inline int btrfs_get_root_log_transid(const struct btrfs_root *root)
{ … }

static inline void btrfs_set_root_log_transid(struct btrfs_root *root, int log_transid)
{ … }

static inline int btrfs_get_root_last_log_commit(const struct btrfs_root *root)
{ … }

static inline void btrfs_set_root_last_log_commit(struct btrfs_root *root, int commit_id)
{ … }

static inline u64 btrfs_get_root_last_trans(const struct btrfs_root *root)
{ … }

static inline void btrfs_set_root_last_trans(struct btrfs_root *root, u64 transid)
{ … }

/*
 * Structure that conveys information about an extent that is going to replace
 * all the extents in a file range.
 */
struct btrfs_replace_extent_info { … };

/* Arguments for btrfs_drop_extents() */
struct btrfs_drop_extents_args { … };

struct btrfs_file_private { … };

static inline u32 BTRFS_LEAF_DATA_SIZE(const struct btrfs_fs_info *info)
{ … }

static inline u32 BTRFS_MAX_ITEM_SIZE(const struct btrfs_fs_info *info)
{ … }

static inline u32 BTRFS_NODEPTRS_PER_BLOCK(const struct btrfs_fs_info *info)
{ … }

static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info)
{ … }

#define BTRFS_BYTES_TO_BLKS(fs_info, bytes) …

static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping)
{ … }

void 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);

#ifdef __LITTLE_ENDIAN

/*
 * Compare two keys, on little-endian the disk order is same as CPU order and
 * we can avoid the conversion.
 */
static inline int btrfs_comp_keys(const struct btrfs_disk_key *disk_key,
				  const struct btrfs_key *k2)
{ … }

#else

/* Compare two keys in a memcmp fashion. */
static inline int btrfs_comp_keys(const struct btrfs_disk_key *disk,
				  const struct btrfs_key *k2)
{
	struct btrfs_key k1;

	btrfs_disk_key_to_cpu(&k1, disk);

	return btrfs_comp_cpu_keys(&k1, k2);
}

#endif

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_force_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,
			  u64 search_start, u64 empty_size,
			  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);
bool 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);
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)
{ … }

/*
 * Describes a batch of items to insert in a btree. This is used by
 * btrfs_insert_empty_items().
 */
struct btrfs_item_batch { … };

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)
{ … }

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) …

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)
{ … }

static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p)
{ … }
int btrfs_leaf_free_space(const struct extent_buffer *leaf);

static inline int is_fstree(u64 rootid)
{ … }

static inline bool btrfs_is_data_reloc_root(const struct btrfs_root *root)
{ … }

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) …
#define SetPageOrdered(page) …
#define ClearPageOrdered(page) …
#define folio_test_ordered(folio) …
#define folio_set_ordered(folio) …
#define folio_clear_ordered(folio) …

#endif