fs/btrfs/ctree.h - LeafOS-Devices/android_kernel_realme_mt6785 - Gitiles

 #ifndef __BTRFS__
 #define __BTRFS__

 #include "list.h"
 #include "kerncompat.h"

 #define BTRFS_MAGIC "_BtRfS_M"

 #define BTRFS_ROOT_TREE_OBJECTID 1
 #define BTRFS_EXTENT_TREE_OBJECTID 2
 #define BTRFS_FS_TREE_OBJECTID 3

 /*
  * the key defines the order in the tree, and so it also defines (optimal)
  * block layout.  objectid corresonds to the inode number.  The flags
  * tells us things about the object, and is a kind of stream selector.
  * so for a given inode, keys with flags of 1 might refer to the inode
  * data, flags of 2 may point to file data in the btree and flags == 3
  * may point to extents.
  *
  * offset is the starting byte offset for this key in the stream.
  *
  * btrfs_disk_key is in disk byte order.  struct btrfs_key is always
  * in cpu native order.  Otherwise they are identical and their sizes
  * should be the same (ie both packed)
  */
 struct btrfs_disk_key {
 	__le64 objectid;
 	__le64 offset;
 	__le32 flags;
 } __attribute__ ((__packed__));

 struct btrfs_key {
 	u64 objectid;
 	u64 offset;
 	u32 flags;
 } __attribute__ ((__packed__));

 /*
  * every tree block (leaf or node) starts with this header.
  */
 struct btrfs_header {
 	u8 fsid[16]; /* FS specific uuid */
 	__le64 blocknr; /* which block this node is supposed to live in */
 	__le64 parentid; /* objectid of the tree root */
 	__le32 csum;
 	__le32 ham;
 	__le16 nritems;
 	__le16 flags;
 	/* generation flags to be added */
 } __attribute__ ((__packed__));

 #define BTRFS_MAX_LEVEL 8
 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->blocksize - \
 			        sizeof(struct btrfs_header)) / \
 			       (sizeof(struct btrfs_disk_key) + sizeof(u64)))
 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->blocksize))

 struct btrfs_buffer;
 /*
  * the super block basically lists the main trees of the FS
  * it currently lacks any block count etc etc
  */
 struct btrfs_super_block {
 	u8 fsid[16];    /* FS specific uuid */
 	__le64 blocknr; /* this block number */
 	__le32 csum;
 	__le64 magic;
 	__le32 blocksize;
 	__le64 generation;
 	__le64 root;
 	__le64 total_blocks;
 	__le64 blocks_used;
 } __attribute__ ((__packed__));

 /*
  * A leaf is full of items. offset and size tell us where to find
  * the item in the leaf (relative to the start of the data area)
  */
 struct btrfs_item {
 	struct btrfs_disk_key key;
 	__le32 offset;
 	__le16 size;
 } __attribute__ ((__packed__));

 /*
  * leaves have an item area and a data area:
  * [item0, item1....itemN] [free space] [dataN...data1, data0]
  *
  * The data is separate from the items to get the keys closer together
  * during searches.
  */
 struct btrfs_leaf {
 	struct btrfs_header header;
 	struct btrfs_item items[];
 } __attribute__ ((__packed__));

 /*
  * all non-leaf blocks are nodes, they hold only keys and pointers to
  * other blocks
  */
 struct btrfs_key_ptr {
 	struct btrfs_disk_key key;
 	__le64 blockptr;
 } __attribute__ ((__packed__));

 struct btrfs_node {
 	struct btrfs_header header;
 	struct btrfs_key_ptr ptrs[];
 } __attribute__ ((__packed__));

 /*
  * 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 btrfs_buffer *nodes[BTRFS_MAX_LEVEL];
 	int slots[BTRFS_MAX_LEVEL];
 };

 /*
  * items in the extent btree are used to record the objectid of the
  * owner of the block and the number of references
  */
 struct btrfs_extent_item {
 	__le32 refs;
 	__le64 owner;
 } __attribute__ ((__packed__));

 struct btrfs_dir_item {
 	__le64 objectid;
 	__le16 flags;
 	u8 type;
 } __attribute__ ((__packed__));

 struct btrfs_root_item {
 	__le64 blocknr;
 	__le32 flags;
 	__le64 block_limit;
 	__le64 blocks_used;
 	__le32 refs;
 };

 /*
  * in ram representation of the tree.  extent_root is used for all allocations
  * and for the extent tree extent_root root.  current_insert is used
  * only for the extent tree.
  */
 struct btrfs_root {
 	struct btrfs_buffer *node;
 	struct btrfs_buffer *commit_root;
 	struct btrfs_root *extent_root;
 	struct btrfs_root *tree_root;
 	struct btrfs_key current_insert;
 	struct btrfs_key last_insert;
 	int fp;
 	struct radix_tree_root cache_radix;
 	struct radix_tree_root pinned_radix;
 	struct list_head trans;
 	struct list_head cache;
 	int cache_size;
 	int ref_cows;
 	struct btrfs_root_item root_item;
 	struct btrfs_key root_key;
 	u32 blocksize;
 };


 /* the lower bits in the key flags defines the item type */
 #define BTRFS_KEY_TYPE_MAX	256
 #define BTRFS_KEY_TYPE_MASK	(BTRFS_KEY_TYPE_MAX - 1)
 #define BTRFS_INODE_ITEM_KEY	1
 #define BTRFS_DIR_ITEM_KEY	2
 #define BTRFS_ROOT_ITEM_KEY	3
 #define BTRFS_EXTENT_ITEM_KEY	4
 #define BTRFS_STRING_ITEM_KEY	5

 static inline u64 btrfs_dir_objectid(struct btrfs_dir_item *d)
 {
 	return le64_to_cpu(d->objectid);
 }

 static inline void btrfs_set_dir_objectid(struct btrfs_dir_item *d, u64 val)
 {
 	d->objectid = cpu_to_le64(val);
 }

 static inline u16 btrfs_dir_flags(struct btrfs_dir_item *d)
 {
 	return le16_to_cpu(d->flags);
 }

 static inline void btrfs_set_dir_flags(struct btrfs_dir_item *d, u16 val)
 {
 	d->flags = cpu_to_le16(val);
 }

 static inline u8 btrfs_dir_type(struct btrfs_dir_item *d)
 {
 	return d->type;
 }

 static inline void btrfs_set_dir_type(struct btrfs_dir_item *d, u8 val)
 {
 	d->type = val;
 }


 static inline u64 btrfs_extent_owner(struct btrfs_extent_item *ei)
 {
 	return le64_to_cpu(ei->owner);
 }

 static inline void btrfs_set_extent_owner(struct btrfs_extent_item *ei, u64 val)
 {
 	ei->owner = cpu_to_le64(val);
 }

 static inline u32 btrfs_extent_refs(struct btrfs_extent_item *ei)
 {
 	return le32_to_cpu(ei->refs);
 }

 static inline void btrfs_set_extent_refs(struct btrfs_extent_item *ei, u32 val)
 {
 	ei->refs = cpu_to_le32(val);
 }

 static inline u64 btrfs_node_blockptr(struct btrfs_node *n, int nr)
 {
 	return le64_to_cpu(n->ptrs[nr].blockptr);
 }

 static inline void btrfs_set_node_blockptr(struct btrfs_node *n, int nr,
 					   u64 val)
 {
 	n->ptrs[nr].blockptr = cpu_to_le64(val);
 }

 static inline u32 btrfs_item_offset(struct btrfs_item *item)
 {
 	return le32_to_cpu(item->offset);
 }

 static inline void btrfs_set_item_offset(struct btrfs_item *item, u32 val)
 {
 	item->offset = cpu_to_le32(val);
 }

 static inline u32 btrfs_item_end(struct btrfs_item *item)
 {
 	return le32_to_cpu(item->offset) + le16_to_cpu(item->size);
 }

 static inline u16 btrfs_item_size(struct btrfs_item *item)
 {
 	return le16_to_cpu(item->size);
 }

 static inline void btrfs_set_item_size(struct btrfs_item *item, u16 val)
 {
 	item->size = cpu_to_le16(val);
 }

 static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
 					 struct btrfs_disk_key *disk)
 {
 	cpu->offset = le64_to_cpu(disk->offset);
 	cpu->flags = le32_to_cpu(disk->flags);
 	cpu->objectid = le64_to_cpu(disk->objectid);
 }

 static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
 					 struct btrfs_key *cpu)
 {
 	disk->offset = cpu_to_le64(cpu->offset);
 	disk->flags = cpu_to_le32(cpu->flags);
 	disk->objectid = cpu_to_le64(cpu->objectid);
 }

 static inline u64 btrfs_disk_key_objectid(struct btrfs_disk_key *disk)
 {
 	return le64_to_cpu(disk->objectid);
 }

 static inline void btrfs_set_disk_key_objectid(struct btrfs_disk_key *disk,
 					       u64 val)
 {
 	disk->objectid = cpu_to_le64(val);
 }

 static inline u64 btrfs_disk_key_offset(struct btrfs_disk_key *disk)
 {
 	return le64_to_cpu(disk->offset);
 }

 static inline void btrfs_set_disk_key_offset(struct btrfs_disk_key *disk,
 					     u64 val)
 {
 	disk->offset = cpu_to_le64(val);
 }

 static inline u32 btrfs_disk_key_flags(struct btrfs_disk_key *disk)
 {
 	return le32_to_cpu(disk->flags);
 }

 static inline void btrfs_set_disk_key_flags(struct btrfs_disk_key *disk,
 					    u32 val)
 {
 	disk->flags = cpu_to_le32(val);
 }

 static inline u32 btrfs_key_type(struct btrfs_key *key)
 {
 	return key->flags & BTRFS_KEY_TYPE_MASK;
 }

 static inline u32 btrfs_disk_key_type(struct btrfs_disk_key *key)
 {
 	return le32_to_cpu(key->flags) & BTRFS_KEY_TYPE_MASK;
 }

 static inline void btrfs_set_key_type(struct btrfs_key *key, u32 type)
 {
 	BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
 	key->flags = (key->flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
 }

 static inline void btrfs_set_disk_key_type(struct btrfs_disk_key *key, u32 type)
 {
 	u32 flags = btrfs_disk_key_flags(key);
 	BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
 	flags = (flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
 	btrfs_set_disk_key_flags(key, flags);
 }


 static inline u64 btrfs_header_blocknr(struct btrfs_header *h)
 {
 	return le64_to_cpu(h->blocknr);
 }

 static inline void btrfs_set_header_blocknr(struct btrfs_header *h, u64 blocknr)
 {
 	h->blocknr = cpu_to_le64(blocknr);
 }

 static inline u64 btrfs_header_parentid(struct btrfs_header *h)
 {
 	return le64_to_cpu(h->parentid);
 }

 static inline void btrfs_set_header_parentid(struct btrfs_header *h,
 					     u64 parentid)
 {
 	h->parentid = cpu_to_le64(parentid);
 }

 static inline u16 btrfs_header_nritems(struct btrfs_header *h)
 {
 	return le16_to_cpu(h->nritems);
 }

 static inline void btrfs_set_header_nritems(struct btrfs_header *h, u16 val)
 {
 	h->nritems = cpu_to_le16(val);
 }

 static inline u16 btrfs_header_flags(struct btrfs_header *h)
 {
 	return le16_to_cpu(h->flags);
 }

 static inline void btrfs_set_header_flags(struct btrfs_header *h, u16 val)
 {
 	h->flags = cpu_to_le16(val);
 }

 static inline int btrfs_header_level(struct btrfs_header *h)
 {
 	return btrfs_header_flags(h) & (BTRFS_MAX_LEVEL - 1);
 }

 static inline void btrfs_set_header_level(struct btrfs_header *h, int level)
 {
 	u16 flags;
 	BUG_ON(level > BTRFS_MAX_LEVEL);
 	flags = btrfs_header_flags(h) & ~(BTRFS_MAX_LEVEL - 1);
 	btrfs_set_header_flags(h, flags | level);
 }

 static inline int btrfs_is_leaf(struct btrfs_node *n)
 {
 	return (btrfs_header_level(&n->header) == 0);
 }

 static inline u64 btrfs_root_blocknr(struct btrfs_root_item *item)
 {
 	return le64_to_cpu(item->blocknr);
 }

 static inline void btrfs_set_root_blocknr(struct btrfs_root_item *item, u64 val)
 {
 	item->blocknr = cpu_to_le64(val);
 }

 static inline u32 btrfs_root_refs(struct btrfs_root_item *item)
 {
 	return le32_to_cpu(item->refs);
 }

 static inline void btrfs_set_root_refs(struct btrfs_root_item *item, u32 val)
 {
 	item->refs = cpu_to_le32(val);
 }

 static inline u64 btrfs_super_blocknr(struct btrfs_super_block *s)
 {
 	return le64_to_cpu(s->blocknr);
 }

 static inline void btrfs_set_super_blocknr(struct btrfs_super_block *s, u64 val)
 {
 	s->blocknr = cpu_to_le64(val);
 }

 static inline u64 btrfs_super_root(struct btrfs_super_block *s)
 {
 	return le64_to_cpu(s->root);
 }

 static inline void btrfs_set_super_root(struct btrfs_super_block *s, u64 val)
 {
 	s->root = cpu_to_le64(val);
 }

 static inline u64 btrfs_super_total_blocks(struct btrfs_super_block *s)
 {
 	return le64_to_cpu(s->total_blocks);
 }

 static inline void btrfs_set_super_total_blocks(struct btrfs_super_block *s,
 						u64 val)
 {
 	s->total_blocks = cpu_to_le64(val);
 }

 static inline u64 btrfs_super_blocks_used(struct btrfs_super_block *s)
 {
 	return le64_to_cpu(s->blocks_used);
 }

 static inline void btrfs_set_super_blocks_used(struct btrfs_super_block *s,
 						u64 val)
 {
 	s->blocks_used = cpu_to_le64(val);
 }

 static inline u32 btrfs_super_blocksize(struct btrfs_super_block *s)
 {
 	return le32_to_cpu(s->blocksize);
 }

 static inline void btrfs_set_super_blocksize(struct btrfs_super_block *s,
 						u32 val)
 {
 	s->blocksize = cpu_to_le32(val);
 }

 static inline u8 *btrfs_leaf_data(struct btrfs_leaf *l)
 {
 	return (u8 *)l->items;
 }
 /* helper function to cast into the data area of the leaf. */
 #define btrfs_item_ptr(leaf, slot, type) \
 	((type *)(btrfs_leaf_data(leaf) + \
 	btrfs_item_offset((leaf)->items + (slot))))

 struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_root *root);
 int btrfs_inc_ref(struct btrfs_root *root, struct btrfs_buffer *buf);
 int btrfs_free_extent(struct btrfs_root *root, u64 blocknr, u64 num_blocks);
 int btrfs_search_slot(struct btrfs_root *root, struct btrfs_key *key,
 		struct btrfs_path *p, int ins_len, int cow);
 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
 void btrfs_init_path(struct btrfs_path *p);
 int btrfs_del_item(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *key,
 		void *data, u32 data_size);
 int btrfs_insert_empty_item(struct btrfs_root *root, struct btrfs_path *path,
 			    struct btrfs_key *cpu_key, u32 data_size);
 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf);
 int btrfs_drop_snapshot(struct btrfs_root *root, struct btrfs_buffer *snap);
 int btrfs_finish_extent_commit(struct btrfs_root *root);
 int btrfs_del_root(struct btrfs_root *root, struct btrfs_key *key);
 int btrfs_insert_root(struct btrfs_root *root, struct btrfs_key *key,
 		      struct btrfs_root_item *item);
 int btrfs_update_root(struct btrfs_root *root, struct btrfs_key *key,
 		      struct btrfs_root_item *item);
 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
 			struct btrfs_root_item *item, struct btrfs_key *key);
 #endif
	#ifndef __BTRFS__
	#define __BTRFS__

	#include "list.h"
	#include "kerncompat.h"

	#define BTRFS_MAGIC "_BtRfS_M"

	#define BTRFS_ROOT_TREE_OBJECTID 1
	#define BTRFS_EXTENT_TREE_OBJECTID 2
	#define BTRFS_FS_TREE_OBJECTID 3

	/*
	* the key defines the order in the tree, and so it also defines (optimal)
	* block layout. objectid corresonds to the inode number. The flags
	* tells us things about the object, and is a kind of stream selector.
	* so for a given inode, keys with flags of 1 might refer to the inode
	* data, flags of 2 may point to file data in the btree and flags == 3
	* may point to extents.
	*
	* offset is the starting byte offset for this key in the stream.
	*
	* btrfs_disk_key is in disk byte order. struct btrfs_key is always
	* in cpu native order. Otherwise they are identical and their sizes
	* should be the same (ie both packed)
	*/
	struct btrfs_disk_key {
	__le64 objectid;
	__le64 offset;
	__le32 flags;
	} __attribute__ ((__packed__));

	struct btrfs_key {
	u64 objectid;
	u64 offset;
	u32 flags;
	} __attribute__ ((__packed__));

	/*
	* every tree block (leaf or node) starts with this header.
	*/
	struct btrfs_header {
	u8 fsid[16]; /* FS specific uuid */
	__le64 blocknr; /* which block this node is supposed to live in */
	__le64 parentid; /* objectid of the tree root */
	__le32 csum;
	__le32 ham;
	__le16 nritems;
	__le16 flags;
	/* generation flags to be added */
	} __attribute__ ((__packed__));

	#define BTRFS_MAX_LEVEL 8
	#define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->blocksize - \
	sizeof(struct btrfs_header)) / \
	(sizeof(struct btrfs_disk_key) + sizeof(u64)))
	#define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
	#define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->blocksize))

	struct btrfs_buffer;
	/*
	* the super block basically lists the main trees of the FS
	* it currently lacks any block count etc etc
	*/
	struct btrfs_super_block {
	u8 fsid[16]; /* FS specific uuid */
	__le64 blocknr; /* this block number */
	__le32 csum;
	__le64 magic;
	__le32 blocksize;
	__le64 generation;
	__le64 root;
	__le64 total_blocks;
	__le64 blocks_used;
	} __attribute__ ((__packed__));

	/*
	* A leaf is full of items. offset and size tell us where to find
	* the item in the leaf (relative to the start of the data area)
	*/
	struct btrfs_item {
	struct btrfs_disk_key key;
	__le32 offset;
	__le16 size;
	} __attribute__ ((__packed__));

	/*
	* leaves have an item area and a data area:
	* [item0, item1....itemN] [free space] [dataN...data1, data0]
	*
	* The data is separate from the items to get the keys closer together
	* during searches.
	*/
	struct btrfs_leaf {
	struct btrfs_header header;
	struct btrfs_item items[];
	} __attribute__ ((__packed__));

	/*
	* all non-leaf blocks are nodes, they hold only keys and pointers to
	* other blocks
	*/
	struct btrfs_key_ptr {
	struct btrfs_disk_key key;
	__le64 blockptr;
	} __attribute__ ((__packed__));

	struct btrfs_node {
	struct btrfs_header header;
	struct btrfs_key_ptr ptrs[];
	} __attribute__ ((__packed__));

	/*
	* 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 btrfs_buffer *nodes[BTRFS_MAX_LEVEL];
	int slots[BTRFS_MAX_LEVEL];
	};

	/*
	* items in the extent btree are used to record the objectid of the
	* owner of the block and the number of references
	*/
	struct btrfs_extent_item {
	__le32 refs;
	__le64 owner;
	} __attribute__ ((__packed__));

	struct btrfs_dir_item {
	__le64 objectid;
	__le16 flags;
	u8 type;
	} __attribute__ ((__packed__));

	struct btrfs_root_item {
	__le64 blocknr;
	__le32 flags;
	__le64 block_limit;
	__le64 blocks_used;
	__le32 refs;
	};

	/*
	* in ram representation of the tree. extent_root is used for all allocations
	* and for the extent tree extent_root root. current_insert is used
	* only for the extent tree.
	*/
	struct btrfs_root {
	struct btrfs_buffer *node;
	struct btrfs_buffer *commit_root;
	struct btrfs_root *extent_root;
	struct btrfs_root *tree_root;
	struct btrfs_key current_insert;
	struct btrfs_key last_insert;
	int fp;
	struct radix_tree_root cache_radix;
	struct radix_tree_root pinned_radix;
	struct list_head trans;
	struct list_head cache;
	int cache_size;
	int ref_cows;
	struct btrfs_root_item root_item;
	struct btrfs_key root_key;
	u32 blocksize;
	};


	/* the lower bits in the key flags defines the item type */
	#define BTRFS_KEY_TYPE_MAX 256
	#define BTRFS_KEY_TYPE_MASK (BTRFS_KEY_TYPE_MAX - 1)
	#define BTRFS_INODE_ITEM_KEY 1
	#define BTRFS_DIR_ITEM_KEY 2
	#define BTRFS_ROOT_ITEM_KEY 3
	#define BTRFS_EXTENT_ITEM_KEY 4
	#define BTRFS_STRING_ITEM_KEY 5

	static inline u64 btrfs_dir_objectid(struct btrfs_dir_item *d)
	{
	return le64_to_cpu(d->objectid);
	}

	static inline void btrfs_set_dir_objectid(struct btrfs_dir_item *d, u64 val)
	{
	d->objectid = cpu_to_le64(val);
	}

	static inline u16 btrfs_dir_flags(struct btrfs_dir_item *d)
	{
	return le16_to_cpu(d->flags);
	}

	static inline void btrfs_set_dir_flags(struct btrfs_dir_item *d, u16 val)
	{
	d->flags = cpu_to_le16(val);
	}

	static inline u8 btrfs_dir_type(struct btrfs_dir_item *d)
	{
	return d->type;
	}

	static inline void btrfs_set_dir_type(struct btrfs_dir_item *d, u8 val)
	{
	d->type = val;
	}


	static inline u64 btrfs_extent_owner(struct btrfs_extent_item *ei)
	{
	return le64_to_cpu(ei->owner);
	}

	static inline void btrfs_set_extent_owner(struct btrfs_extent_item *ei, u64 val)
	{
	ei->owner = cpu_to_le64(val);
	}

	static inline u32 btrfs_extent_refs(struct btrfs_extent_item *ei)
	{
	return le32_to_cpu(ei->refs);
	}

	static inline void btrfs_set_extent_refs(struct btrfs_extent_item *ei, u32 val)
	{
	ei->refs = cpu_to_le32(val);
	}

	static inline u64 btrfs_node_blockptr(struct btrfs_node *n, int nr)
	{
	return le64_to_cpu(n->ptrs[nr].blockptr);
	}

	static inline void btrfs_set_node_blockptr(struct btrfs_node *n, int nr,
	u64 val)
	{
	n->ptrs[nr].blockptr = cpu_to_le64(val);
	}

	static inline u32 btrfs_item_offset(struct btrfs_item *item)
	{
	return le32_to_cpu(item->offset);
	}

	static inline void btrfs_set_item_offset(struct btrfs_item *item, u32 val)
	{
	item->offset = cpu_to_le32(val);
	}

	static inline u32 btrfs_item_end(struct btrfs_item *item)
	{
	return le32_to_cpu(item->offset) + le16_to_cpu(item->size);
	}

	static inline u16 btrfs_item_size(struct btrfs_item *item)
	{
	return le16_to_cpu(item->size);
	}

	static inline void btrfs_set_item_size(struct btrfs_item *item, u16 val)
	{
	item->size = cpu_to_le16(val);
	}

	static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
	struct btrfs_disk_key *disk)
	{
	cpu->offset = le64_to_cpu(disk->offset);
	cpu->flags = le32_to_cpu(disk->flags);
	cpu->objectid = le64_to_cpu(disk->objectid);
	}

	static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
	struct btrfs_key *cpu)
	{
	disk->offset = cpu_to_le64(cpu->offset);
	disk->flags = cpu_to_le32(cpu->flags);
	disk->objectid = cpu_to_le64(cpu->objectid);
	}

	static inline u64 btrfs_disk_key_objectid(struct btrfs_disk_key *disk)
	{
	return le64_to_cpu(disk->objectid);
	}

	static inline void btrfs_set_disk_key_objectid(struct btrfs_disk_key *disk,
	u64 val)
	{
	disk->objectid = cpu_to_le64(val);
	}

	static inline u64 btrfs_disk_key_offset(struct btrfs_disk_key *disk)
	{
	return le64_to_cpu(disk->offset);
	}

	static inline void btrfs_set_disk_key_offset(struct btrfs_disk_key *disk,
	u64 val)
	{
	disk->offset = cpu_to_le64(val);
	}

	static inline u32 btrfs_disk_key_flags(struct btrfs_disk_key *disk)
	{
	return le32_to_cpu(disk->flags);
	}

	static inline void btrfs_set_disk_key_flags(struct btrfs_disk_key *disk,
	u32 val)
	{
	disk->flags = cpu_to_le32(val);
	}

	static inline u32 btrfs_key_type(struct btrfs_key *key)
	{
	return key->flags & BTRFS_KEY_TYPE_MASK;
	}

	static inline u32 btrfs_disk_key_type(struct btrfs_disk_key *key)
	{
	return le32_to_cpu(key->flags) & BTRFS_KEY_TYPE_MASK;
	}

	static inline void btrfs_set_key_type(struct btrfs_key *key, u32 type)
	{
	BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
	key->flags = (key->flags & ~((u64)BTRFS_KEY_TYPE_MASK)) \| type;
	}

	static inline void btrfs_set_disk_key_type(struct btrfs_disk_key *key, u32 type)
	{
	u32 flags = btrfs_disk_key_flags(key);
	BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
	flags = (flags & ~((u64)BTRFS_KEY_TYPE_MASK)) \| type;
	btrfs_set_disk_key_flags(key, flags);
	}



	static inline u64 btrfs_header_blocknr(struct btrfs_header *h)
	{
	return le64_to_cpu(h->blocknr);
	}

	static inline void btrfs_set_header_blocknr(struct btrfs_header *h, u64 blocknr)
	{
	h->blocknr = cpu_to_le64(blocknr);
	}

	static inline u64 btrfs_header_parentid(struct btrfs_header *h)
	{
	return le64_to_cpu(h->parentid);
	}

	static inline void btrfs_set_header_parentid(struct btrfs_header *h,
	u64 parentid)
	{
	h->parentid = cpu_to_le64(parentid);
	}

	static inline u16 btrfs_header_nritems(struct btrfs_header *h)
	{
	return le16_to_cpu(h->nritems);
	}

	static inline void btrfs_set_header_nritems(struct btrfs_header *h, u16 val)
	{
	h->nritems = cpu_to_le16(val);
	}

	static inline u16 btrfs_header_flags(struct btrfs_header *h)
	{
	return le16_to_cpu(h->flags);
	}

	static inline void btrfs_set_header_flags(struct btrfs_header *h, u16 val)
	{
	h->flags = cpu_to_le16(val);
	}

	static inline int btrfs_header_level(struct btrfs_header *h)
	{
	return btrfs_header_flags(h) & (BTRFS_MAX_LEVEL - 1);
	}

	static inline void btrfs_set_header_level(struct btrfs_header *h, int level)
	{
	u16 flags;
	BUG_ON(level > BTRFS_MAX_LEVEL);
	flags = btrfs_header_flags(h) & ~(BTRFS_MAX_LEVEL - 1);
	btrfs_set_header_flags(h, flags \| level);
	}

	static inline int btrfs_is_leaf(struct btrfs_node *n)
	{
	return (btrfs_header_level(&n->header) == 0);
	}

	static inline u64 btrfs_root_blocknr(struct btrfs_root_item *item)
	{
	return le64_to_cpu(item->blocknr);
	}

	static inline void btrfs_set_root_blocknr(struct btrfs_root_item *item, u64 val)
	{
	item->blocknr = cpu_to_le64(val);
	}

	static inline u32 btrfs_root_refs(struct btrfs_root_item *item)
	{
	return le32_to_cpu(item->refs);
	}

	static inline void btrfs_set_root_refs(struct btrfs_root_item *item, u32 val)
	{
	item->refs = cpu_to_le32(val);
	}

	static inline u64 btrfs_super_blocknr(struct btrfs_super_block *s)
	{
	return le64_to_cpu(s->blocknr);
	}

	static inline void btrfs_set_super_blocknr(struct btrfs_super_block *s, u64 val)
	{
	s->blocknr = cpu_to_le64(val);
	}

	static inline u64 btrfs_super_root(struct btrfs_super_block *s)
	{
	return le64_to_cpu(s->root);
	}

	static inline void btrfs_set_super_root(struct btrfs_super_block *s, u64 val)
	{
	s->root = cpu_to_le64(val);
	}

	static inline u64 btrfs_super_total_blocks(struct btrfs_super_block *s)
	{
	return le64_to_cpu(s->total_blocks);
	}

	static inline void btrfs_set_super_total_blocks(struct btrfs_super_block *s,
	u64 val)
	{
	s->total_blocks = cpu_to_le64(val);
	}

	static inline u64 btrfs_super_blocks_used(struct btrfs_super_block *s)
	{
	return le64_to_cpu(s->blocks_used);
	}

	static inline void btrfs_set_super_blocks_used(struct btrfs_super_block *s,
	u64 val)
	{
	s->blocks_used = cpu_to_le64(val);
	}

	static inline u32 btrfs_super_blocksize(struct btrfs_super_block *s)
	{
	return le32_to_cpu(s->blocksize);
	}

	static inline void btrfs_set_super_blocksize(struct btrfs_super_block *s,
	u32 val)
	{
	s->blocksize = cpu_to_le32(val);
	}

	static inline u8 btrfs_leaf_data(struct btrfs_leaf l)
	{
	return (u8 *)l->items;
	}
	/* helper function to cast into the data area of the leaf. */
	#define btrfs_item_ptr(leaf, slot, type) \
	((type *)(btrfs_leaf_data(leaf) + \
	btrfs_item_offset((leaf)->items + (slot))))

	struct btrfs_buffer btrfs_alloc_free_block(struct btrfs_root root);
	int btrfs_inc_ref(struct btrfs_root root, struct btrfs_buffer buf);
	int btrfs_free_extent(struct btrfs_root *root, u64 blocknr, u64 num_blocks);
	int btrfs_search_slot(struct btrfs_root root, struct btrfs_key key,
	struct btrfs_path *p, int ins_len, int cow);
	void btrfs_release_path(struct btrfs_root root, struct btrfs_path p);
	void btrfs_init_path(struct btrfs_path *p);
	int btrfs_del_item(struct btrfs_root root, struct btrfs_path path);
	int btrfs_insert_item(struct btrfs_root root, struct btrfs_key key,
	void *data, u32 data_size);
	int btrfs_insert_empty_item(struct btrfs_root root, struct btrfs_path path,
	struct btrfs_key *cpu_key, u32 data_size);
	int btrfs_next_leaf(struct btrfs_root root, struct btrfs_path path);
	int btrfs_leaf_free_space(struct btrfs_root root, struct btrfs_leaf leaf);
	int btrfs_drop_snapshot(struct btrfs_root root, struct btrfs_buffer snap);
	int btrfs_finish_extent_commit(struct btrfs_root *root);
	int btrfs_del_root(struct btrfs_root root, struct btrfs_key key);
	int btrfs_insert_root(struct btrfs_root root, struct btrfs_key key,
	struct btrfs_root_item *item);
	int btrfs_update_root(struct btrfs_root root, struct btrfs_key key,
	struct btrfs_root_item *item);
	int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
	struct btrfs_root_item item, struct btrfs_key key);
	#endif