[deliverable/linux.git] / fs / btrfs / extent_io.h

#ifndef __EXTENTIO__
#define __EXTENTIO__

#include <linux/rbtree.h>

/* bits for the extent state */
#define EXTENT_DIRTY 1
#define EXTENT_WRITEBACK (1 << 1)
#define EXTENT_UPTODATE (1 << 2)
#define EXTENT_LOCKED (1 << 3)
#define EXTENT_NEW (1 << 4)
#define EXTENT_DELALLOC (1 << 5)
#define EXTENT_DEFRAG (1 << 6)
#define EXTENT_DEFRAG_DONE (1 << 7)
#define EXTENT_BUFFER_FILLED (1 << 8)
#define EXTENT_BOUNDARY (1 << 9)
#define EXTENT_NODATASUM (1 << 10)
#define EXTENT_DO_ACCOUNTING (1 << 11)
#define EXTENT_FIRST_DELALLOC (1 << 12)
#define EXTENT_NEED_WAIT (1 << 13)
#define EXTENT_DAMAGED (1 << 14)
#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)

/*
 * flags for bio submission. The high bits indicate the compression
 * type for this bio
 */
#define EXTENT_BIO_COMPRESSED 1
#define EXTENT_BIO_TREE_LOG 2
#define EXTENT_BIO_FLAG_SHIFT 16

/* these are bit numbers for test/set bit */
#define EXTENT_BUFFER_UPTODATE 0
#define EXTENT_BUFFER_BLOCKING 1
#define EXTENT_BUFFER_DIRTY 2
#define EXTENT_BUFFER_CORRUPT 3
#define EXTENT_BUFFER_READAHEAD 4	/* this got triggered by readahead */
#define EXTENT_BUFFER_TREE_REF 5
#define EXTENT_BUFFER_STALE 6
#define EXTENT_BUFFER_WRITEBACK 7
#define EXTENT_BUFFER_IOERR 8
#define EXTENT_BUFFER_DUMMY 9

/* these are flags for extent_clear_unlock_delalloc */
#define EXTENT_CLEAR_UNLOCK_PAGE 0x1
#define EXTENT_CLEAR_UNLOCK	 0x2
#define EXTENT_CLEAR_DELALLOC	 0x4
#define EXTENT_CLEAR_DIRTY	 0x8
#define EXTENT_SET_WRITEBACK	 0x10
#define EXTENT_END_WRITEBACK	 0x20
#define EXTENT_SET_PRIVATE2	 0x40
#define EXTENT_CLEAR_ACCOUNTING  0x80

/*
 * page->private values.  Every page that is controlled by the extent
 * map has page->private set to one.
 */
#define EXTENT_PAGE_PRIVATE 1
#define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3

struct extent_state;
struct btrfs_root;

typedef	int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
				       struct bio *bio, int mirror_num,
				       unsigned long bio_flags, u64 bio_offset);
struct extent_io_ops {
	int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
			     u64 start, u64 end, int *page_started,
			     unsigned long *nr_written);
	int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
	int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
	extent_submit_bio_hook_t *submit_bio_hook;
	int (*merge_bio_hook)(int rw, struct page *page, unsigned long offset,
			      size_t size, struct bio *bio,
			      unsigned long bio_flags);
	int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
	int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
				    struct extent_state *state, int mirror);
	int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
				      struct extent_state *state, int uptodate);
	void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
			     int *bits);
	void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
			       int *bits);
	void (*merge_extent_hook)(struct inode *inode,
				  struct extent_state *new,
				  struct extent_state *other);
	void (*split_extent_hook)(struct inode *inode,
				  struct extent_state *orig, u64 split);
};

struct extent_io_tree {
	struct rb_root state;
	struct radix_tree_root buffer;
	struct address_space *mapping;
	u64 dirty_bytes;
	int track_uptodate;
	spinlock_t lock;
	spinlock_t buffer_lock;
	struct extent_io_ops *ops;
};

struct extent_state {
	u64 start;
	u64 end; /* inclusive */
	struct rb_node rb_node;

	/* ADD NEW ELEMENTS AFTER THIS */
	struct extent_io_tree *tree;
	wait_queue_head_t wq;
	atomic_t refs;
	unsigned long state;

	/* for use by the FS */
	u64 private;

#ifdef CONFIG_BTRFS_DEBUG
	struct list_head leak_list;
#endif
};

#define INLINE_EXTENT_BUFFER_PAGES 16
#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
struct extent_buffer {
	u64 start;
	unsigned long len;
	unsigned long map_start;
	unsigned long map_len;
	unsigned long bflags;
	struct extent_io_tree *tree;
	spinlock_t refs_lock;
	atomic_t refs;
	atomic_t io_pages;
	int read_mirror;
	struct rcu_head rcu_head;
	pid_t lock_owner;

	/* count of read lock holders on the extent buffer */
	atomic_t write_locks;
	atomic_t read_locks;
	atomic_t blocking_writers;
	atomic_t blocking_readers;
	atomic_t spinning_readers;
	atomic_t spinning_writers;
	int lock_nested;

	/* protects write locks */
	rwlock_t lock;

	/* readers use lock_wq while they wait for the write
	 * lock holders to unlock
	 */
	wait_queue_head_t write_lock_wq;

	/* writers use read_lock_wq while they wait for readers
	 * to unlock
	 */
	wait_queue_head_t read_lock_wq;
	wait_queue_head_t lock_wq;
	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
#ifdef CONFIG_BTRFS_DEBUG
	struct list_head leak_list;
#endif
};

static inline void extent_set_compress_type(unsigned long *bio_flags,
					    int compress_type)
{
	*bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
}

static inline int extent_compress_type(unsigned long bio_flags)
{
	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
}

struct extent_map_tree;

typedef struct extent_map *(get_extent_t)(struct inode *inode,
					  struct page *page,
					  size_t pg_offset,
					  u64 start, u64 len,
					  int create);

void extent_io_tree_init(struct extent_io_tree *tree,
			 struct address_space *mapping);
int try_release_extent_mapping(struct extent_map_tree *map,
			       struct extent_io_tree *tree, struct page *page,
			       gfp_t mask);
int try_release_extent_buffer(struct page *page);
int lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
		     int bits, struct extent_state **cached);
int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end);
int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
			 struct extent_state **cached, gfp_t mask);
int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
			  get_extent_t *get_extent, int mirror_num);
int __init extent_io_init(void);
void extent_io_exit(void);

u64 count_range_bits(struct extent_io_tree *tree,
		     u64 *start, u64 search_end,
		     u64 max_bytes, unsigned long bits, int contig);

void free_extent_state(struct extent_state *state);
int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
		   int bits, int filled, struct extent_state *cached_state);
int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
		      int bits, gfp_t mask);
int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
		     int bits, int wake, int delete, struct extent_state **cached,
		     gfp_t mask);
int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
		    int bits, gfp_t mask);
int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
		   int bits, u64 *failed_start,
		   struct extent_state **cached_state, gfp_t mask);
int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
			struct extent_state **cached_state, gfp_t mask);
int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
			  struct extent_state **cached_state, gfp_t mask);
int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
		   gfp_t mask);
int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
		     gfp_t mask);
int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
		       gfp_t mask);
int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
		       int bits, int clear_bits,
		       struct extent_state **cached_state, gfp_t mask);
int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
			struct extent_state **cached_state, gfp_t mask);
int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
		      struct extent_state **cached_state, gfp_t mask);
int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
			  u64 *start_ret, u64 *end_ret, int bits,
			  struct extent_state **cached_state);
int extent_invalidatepage(struct extent_io_tree *tree,
			  struct page *page, unsigned long offset);
int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
			  get_extent_t *get_extent,
			  struct writeback_control *wbc);
int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
			      u64 start, u64 end, get_extent_t *get_extent,
			      int mode);
int extent_writepages(struct extent_io_tree *tree,
		      struct address_space *mapping,
		      get_extent_t *get_extent,
		      struct writeback_control *wbc);
int btree_write_cache_pages(struct address_space *mapping,
			    struct writeback_control *wbc);
int extent_readpages(struct extent_io_tree *tree,
		     struct address_space *mapping,
		     struct list_head *pages, unsigned nr_pages,
		     get_extent_t get_extent);
int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
		__u64 start, __u64 len, get_extent_t *get_extent);
int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
void extent_cache_csums_dio(struct extent_io_tree *tree, u64 start, u32 csums[],
			    int count);
void extent_cache_csums(struct extent_io_tree *tree, struct bio *bio,
			int bvec_index, u32 csums[], int count);
int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
void set_page_extent_mapped(struct page *page);

struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
					  u64 start, unsigned long len);
struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len);
struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
					 u64 start, unsigned long len);
void free_extent_buffer(struct extent_buffer *eb);
void free_extent_buffer_stale(struct extent_buffer *eb);
#define WAIT_NONE	0
#define WAIT_COMPLETE	1
#define WAIT_PAGE_LOCK	2
int read_extent_buffer_pages(struct extent_io_tree *tree,
			     struct extent_buffer *eb, u64 start, int wait,
			     get_extent_t *get_extent, int mirror_num);
void wait_on_extent_buffer_writeback(struct extent_buffer *eb);

static inline unsigned long num_extent_pages(u64 start, u64 len)
{
	return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
		(start >> PAGE_CACHE_SHIFT);
}

static inline struct page *extent_buffer_page(struct extent_buffer *eb,
					      unsigned long i)
{
	return eb->pages[i];
}

static inline void extent_buffer_get(struct extent_buffer *eb)
{
	atomic_inc(&eb->refs);
}

int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
			  unsigned long start,
			  unsigned long len);
void read_extent_buffer(struct extent_buffer *eb, void *dst,
			unsigned long start,
			unsigned long len);
void write_extent_buffer(struct extent_buffer *eb, const void *src,
			 unsigned long start, unsigned long len);
void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
			unsigned long dst_offset, unsigned long src_offset,
			unsigned long len);
void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
			   unsigned long src_offset, unsigned long len);
void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
			   unsigned long src_offset, unsigned long len);
void memset_extent_buffer(struct extent_buffer *eb, char c,
			  unsigned long start, unsigned long len);
void clear_extent_buffer_dirty(struct extent_buffer *eb);
int set_extent_buffer_dirty(struct extent_buffer *eb);
int set_extent_buffer_uptodate(struct extent_buffer *eb);
int clear_extent_buffer_uptodate(struct extent_buffer *eb);
int extent_buffer_uptodate(struct extent_buffer *eb);
int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
		      unsigned long min_len, char **map,
		      unsigned long *map_start,
		      unsigned long *map_len);
int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
int extent_clear_unlock_delalloc(struct inode *inode,
				struct extent_io_tree *tree,
				u64 start, u64 end, struct page *locked_page,
				unsigned long op);
struct bio *
btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
		gfp_t gfp_flags);

struct btrfs_fs_info;

int repair_io_failure(struct btrfs_fs_info *fs_info, u64 start,
			u64 length, u64 logical, struct page *page,
			int mirror_num);
int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
			 int mirror_num);
#endif
Commit	Line	Data
	1	#ifndef __EXTENTIO__
	2	#define __EXTENTIO__
	3
	4	#include <linux/rbtree.h>
	5
	6	/* bits for the extent state */
	7	#define EXTENT_DIRTY 1
	8	#define EXTENT_WRITEBACK (1 << 1)
	9	#define EXTENT_UPTODATE (1 << 2)
	10	#define EXTENT_LOCKED (1 << 3)
	11	#define EXTENT_NEW (1 << 4)
	12	#define EXTENT_DELALLOC (1 << 5)
	13	#define EXTENT_DEFRAG (1 << 6)
	14	#define EXTENT_DEFRAG_DONE (1 << 7)
	15	#define EXTENT_BUFFER_FILLED (1 << 8)
	16	#define EXTENT_BOUNDARY (1 << 9)
	17	#define EXTENT_NODATASUM (1 << 10)
	18	#define EXTENT_DO_ACCOUNTING (1 << 11)
	19	#define EXTENT_FIRST_DELALLOC (1 << 12)
	20	#define EXTENT_NEED_WAIT (1 << 13)
	21	#define EXTENT_DAMAGED (1 << 14)
	22	#define EXTENT_IOBITS (EXTENT_LOCKED \| EXTENT_WRITEBACK)
	23	#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING \| EXTENT_FIRST_DELALLOC)
	24
	25	/*
	26	* flags for bio submission. The high bits indicate the compression
	27	* type for this bio
	28	*/
	29	#define EXTENT_BIO_COMPRESSED 1
	30	#define EXTENT_BIO_TREE_LOG 2
	31	#define EXTENT_BIO_FLAG_SHIFT 16
	32
	33	/* these are bit numbers for test/set bit */
	34	#define EXTENT_BUFFER_UPTODATE 0
	35	#define EXTENT_BUFFER_BLOCKING 1
	36	#define EXTENT_BUFFER_DIRTY 2
	37	#define EXTENT_BUFFER_CORRUPT 3
	38	#define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
	39	#define EXTENT_BUFFER_TREE_REF 5
	40	#define EXTENT_BUFFER_STALE 6
	41	#define EXTENT_BUFFER_WRITEBACK 7
	42	#define EXTENT_BUFFER_IOERR 8
	43	#define EXTENT_BUFFER_DUMMY 9
	44
	45	/* these are flags for extent_clear_unlock_delalloc */
	46	#define EXTENT_CLEAR_UNLOCK_PAGE 0x1
	47	#define EXTENT_CLEAR_UNLOCK 0x2
	48	#define EXTENT_CLEAR_DELALLOC 0x4
	49	#define EXTENT_CLEAR_DIRTY 0x8
	50	#define EXTENT_SET_WRITEBACK 0x10
	51	#define EXTENT_END_WRITEBACK 0x20
	52	#define EXTENT_SET_PRIVATE2 0x40
	53	#define EXTENT_CLEAR_ACCOUNTING 0x80
	54
	55	/*
	56	* page->private values. Every page that is controlled by the extent
	57	* map has page->private set to one.
	58	*/
	59	#define EXTENT_PAGE_PRIVATE 1
	60	#define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3
	61
	62	struct extent_state;
	63	struct btrfs_root;
	64
	65	typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
	66	struct bio *bio, int mirror_num,
	67	unsigned long bio_flags, u64 bio_offset);
	68	struct extent_io_ops {
	69	int (fill_delalloc)(struct inode inode, struct page *locked_page,
	70	u64 start, u64 end, int *page_started,
	71	unsigned long *nr_written);
	72	int (writepage_start_hook)(struct page page, u64 start, u64 end);
	73	int (writepage_io_hook)(struct page page, u64 start, u64 end);
	74	extent_submit_bio_hook_t *submit_bio_hook;
	75	int (merge_bio_hook)(int rw, struct page page, unsigned long offset,
	76	size_t size, struct bio *bio,
	77	unsigned long bio_flags);
	78	int (readpage_io_failed_hook)(struct page page, int failed_mirror);
	79	int (readpage_end_io_hook)(struct page page, u64 start, u64 end,
	80	struct extent_state *state, int mirror);
	81	int (writepage_end_io_hook)(struct page page, u64 start, u64 end,
	82	struct extent_state *state, int uptodate);
	83	void (set_bit_hook)(struct inode inode, struct extent_state *state,
	84	int *bits);
	85	void (clear_bit_hook)(struct inode inode, struct extent_state *state,
	86	int *bits);
	87	void (merge_extent_hook)(struct inode inode,
	88	struct extent_state *new,
	89	struct extent_state *other);
	90	void (split_extent_hook)(struct inode inode,
	91	struct extent_state *orig, u64 split);
	92	};
	93
	94	struct extent_io_tree {
	95	struct rb_root state;
	96	struct radix_tree_root buffer;
	97	struct address_space *mapping;
	98	u64 dirty_bytes;
	99	int track_uptodate;
	100	spinlock_t lock;
	101	spinlock_t buffer_lock;
	102	struct extent_io_ops *ops;
	103	};
	104
	105	struct extent_state {
	106	u64 start;
	107	u64 end; /* inclusive */
	108	struct rb_node rb_node;
	109
	110	/* ADD NEW ELEMENTS AFTER THIS */
	111	struct extent_io_tree *tree;
	112	wait_queue_head_t wq;
	113	atomic_t refs;
	114	unsigned long state;
	115
	116	/* for use by the FS */
	117	u64 private;
	118
	119	#ifdef CONFIG_BTRFS_DEBUG
	120	struct list_head leak_list;
	121	#endif
	122	};
	123
	124	#define INLINE_EXTENT_BUFFER_PAGES 16
	125	#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
	126	struct extent_buffer {
	127	u64 start;
	128	unsigned long len;
	129	unsigned long map_start;
	130	unsigned long map_len;
	131	unsigned long bflags;
	132	struct extent_io_tree *tree;
	133	spinlock_t refs_lock;
	134	atomic_t refs;
	135	atomic_t io_pages;
	136	int read_mirror;
	137	struct rcu_head rcu_head;
	138	pid_t lock_owner;
	139
	140	/* count of read lock holders on the extent buffer */
	141	atomic_t write_locks;
	142	atomic_t read_locks;
	143	atomic_t blocking_writers;
	144	atomic_t blocking_readers;
	145	atomic_t spinning_readers;
	146	atomic_t spinning_writers;
	147	int lock_nested;
	148
	149	/* protects write locks */
	150	rwlock_t lock;
	151
	152	/* readers use lock_wq while they wait for the write
	153	* lock holders to unlock
	154	*/
	155	wait_queue_head_t write_lock_wq;
	156
	157	/* writers use read_lock_wq while they wait for readers
	158	* to unlock
	159	*/
	160	wait_queue_head_t read_lock_wq;
	161	wait_queue_head_t lock_wq;
	162	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
	163	#ifdef CONFIG_BTRFS_DEBUG
	164	struct list_head leak_list;
	165	#endif
	166	};
	167
	168	static inline void extent_set_compress_type(unsigned long *bio_flags,
	169	int compress_type)
	170	{
	171	*bio_flags \|= compress_type << EXTENT_BIO_FLAG_SHIFT;
	172	}
	173
	174	static inline int extent_compress_type(unsigned long bio_flags)
	175	{
	176	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
	177	}
	178
	179	struct extent_map_tree;
	180
	181	typedef struct extent_map (get_extent_t)(struct inode inode,
	182	struct page *page,
	183	size_t pg_offset,
	184	u64 start, u64 len,
	185	int create);
	186
	187	void extent_io_tree_init(struct extent_io_tree *tree,
	188	struct address_space *mapping);
	189	int try_release_extent_mapping(struct extent_map_tree *map,
	190	struct extent_io_tree tree, struct page page,
	191	gfp_t mask);
	192	int try_release_extent_buffer(struct page *page);
	193	int lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
	194	int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
	195	int bits, struct extent_state **cached);
	196	int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end);
	197	int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
	198	struct extent_state **cached, gfp_t mask);
	199	int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
	200	int extent_read_full_page(struct extent_io_tree tree, struct page page,
	201	get_extent_t *get_extent, int mirror_num);
	202	int __init extent_io_init(void);
	203	void extent_io_exit(void);
	204
	205	u64 count_range_bits(struct extent_io_tree *tree,
	206	u64 *start, u64 search_end,
	207	u64 max_bytes, unsigned long bits, int contig);
	208
	209	void free_extent_state(struct extent_state *state);
	210	int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
	211	int bits, int filled, struct extent_state *cached_state);
	212	int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
	213	int bits, gfp_t mask);
	214	int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
	215	int bits, int wake, int delete, struct extent_state **cached,
	216	gfp_t mask);
	217	int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
	218	int bits, gfp_t mask);
	219	int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
	220	int bits, u64 *failed_start,
	221	struct extent_state **cached_state, gfp_t mask);
	222	int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
	223	struct extent_state **cached_state, gfp_t mask);
	224	int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
	225	struct extent_state **cached_state, gfp_t mask);
	226	int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
	227	gfp_t mask);
	228	int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
	229	gfp_t mask);
	230	int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
	231	gfp_t mask);
	232	int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
	233	int bits, int clear_bits,
	234	struct extent_state **cached_state, gfp_t mask);
	235	int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
	236	struct extent_state **cached_state, gfp_t mask);
	237	int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
	238	struct extent_state **cached_state, gfp_t mask);
	239	int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
	240	u64 start_ret, u64 end_ret, int bits,
	241	struct extent_state **cached_state);
	242	int extent_invalidatepage(struct extent_io_tree *tree,
	243	struct page *page, unsigned long offset);
	244	int extent_write_full_page(struct extent_io_tree tree, struct page page,
	245	get_extent_t *get_extent,
	246	struct writeback_control *wbc);
	247	int extent_write_locked_range(struct extent_io_tree tree, struct inode inode,
	248	u64 start, u64 end, get_extent_t *get_extent,
	249	int mode);
	250	int extent_writepages(struct extent_io_tree *tree,
	251	struct address_space *mapping,
	252	get_extent_t *get_extent,
	253	struct writeback_control *wbc);
	254	int btree_write_cache_pages(struct address_space *mapping,
	255	struct writeback_control *wbc);
	256	int extent_readpages(struct extent_io_tree *tree,
	257	struct address_space *mapping,
	258	struct list_head *pages, unsigned nr_pages,
	259	get_extent_t get_extent);
	260	int extent_fiemap(struct inode inode, struct fiemap_extent_info fieinfo,
	261	__u64 start, __u64 len, get_extent_t *get_extent);
	262	int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
	263	void extent_cache_csums_dio(struct extent_io_tree *tree, u64 start, u32 csums[],
	264	int count);
	265	void extent_cache_csums(struct extent_io_tree tree, struct bio bio,
	266	int bvec_index, u32 csums[], int count);
	267	int get_state_private(struct extent_io_tree tree, u64 start, u64 private);
	268	void set_page_extent_mapped(struct page *page);
	269
	270	struct extent_buffer alloc_extent_buffer(struct extent_io_tree tree,
	271	u64 start, unsigned long len);
	272	struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len);
	273	struct extent_buffer btrfs_clone_extent_buffer(struct extent_buffer src);
	274	struct extent_buffer find_extent_buffer(struct extent_io_tree tree,
	275	u64 start, unsigned long len);
	276	void free_extent_buffer(struct extent_buffer *eb);
	277	void free_extent_buffer_stale(struct extent_buffer *eb);
	278	#define WAIT_NONE 0
	279	#define WAIT_COMPLETE 1
	280	#define WAIT_PAGE_LOCK 2
	281	int read_extent_buffer_pages(struct extent_io_tree *tree,
	282	struct extent_buffer *eb, u64 start, int wait,
	283	get_extent_t *get_extent, int mirror_num);
	284	void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
	285
	286	static inline unsigned long num_extent_pages(u64 start, u64 len)
	287	{
	288	return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
	289	(start >> PAGE_CACHE_SHIFT);
	290	}
	291
	292	static inline struct page extent_buffer_page(struct extent_buffer eb,
	293	unsigned long i)
	294	{
	295	return eb->pages[i];
	296	}
	297
	298	static inline void extent_buffer_get(struct extent_buffer *eb)
	299	{
	300	atomic_inc(&eb->refs);
	301	}
	302
	303	int memcmp_extent_buffer(struct extent_buffer eb, const void ptrv,
	304	unsigned long start,
	305	unsigned long len);
	306	void read_extent_buffer(struct extent_buffer eb, void dst,
	307	unsigned long start,
	308	unsigned long len);
	309	void write_extent_buffer(struct extent_buffer eb, const void src,
	310	unsigned long start, unsigned long len);
	311	void copy_extent_buffer(struct extent_buffer dst, struct extent_buffer src,
	312	unsigned long dst_offset, unsigned long src_offset,
	313	unsigned long len);
	314	void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
	315	unsigned long src_offset, unsigned long len);
	316	void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
	317	unsigned long src_offset, unsigned long len);
	318	void memset_extent_buffer(struct extent_buffer *eb, char c,
	319	unsigned long start, unsigned long len);
	320	void clear_extent_buffer_dirty(struct extent_buffer *eb);
	321	int set_extent_buffer_dirty(struct extent_buffer *eb);
	322	int set_extent_buffer_uptodate(struct extent_buffer *eb);
	323	int clear_extent_buffer_uptodate(struct extent_buffer *eb);
	324	int extent_buffer_uptodate(struct extent_buffer *eb);
	325	int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
	326	unsigned long min_len, char **map,
	327	unsigned long *map_start,
	328	unsigned long *map_len);
	329	int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
	330	int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
	331	int extent_clear_unlock_delalloc(struct inode *inode,
	332	struct extent_io_tree *tree,
	333	u64 start, u64 end, struct page *locked_page,
	334	unsigned long op);
	335	struct bio *
	336	btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
	337	gfp_t gfp_flags);
	338
	339	struct btrfs_fs_info;
	340
	341	int repair_io_failure(struct btrfs_fs_info *fs_info, u64 start,
	342	u64 length, u64 logical, struct page *page,
	343	int mirror_num);
	344	int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
	345	int repair_eb_io_failure(struct btrfs_root root, struct extent_buffer eb,
	346	int mirror_num);
	347	#endif