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

#ifndef __EXTENTIO__
#define __EXTENTIO__

#include <linux/rbtree.h>
#include "ulist.h"

/* bits for the extent state */
#define EXTENT_DIRTY		(1U << 0)
#define EXTENT_WRITEBACK	(1U << 1)
#define EXTENT_UPTODATE		(1U << 2)
#define EXTENT_LOCKED		(1U << 3)
#define EXTENT_NEW		(1U << 4)
#define EXTENT_DELALLOC		(1U << 5)
#define EXTENT_DEFRAG		(1U << 6)
#define EXTENT_BOUNDARY		(1U << 9)
#define EXTENT_NODATASUM	(1U << 10)
#define EXTENT_DO_ACCOUNTING	(1U << 11)
#define EXTENT_FIRST_DELALLOC	(1U << 12)
#define EXTENT_NEED_WAIT	(1U << 13)
#define EXTENT_DAMAGED		(1U << 14)
#define EXTENT_NORESERVE	(1U << 15)
#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_PARENT_LOCKED 4
#define EXTENT_BIO_FLAG_SHIFT 16

/* these are bit numbers for test/set bit */
#define EXTENT_BUFFER_UPTODATE 0
#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_READ_ERR 8        /* read IO error */
#define EXTENT_BUFFER_DUMMY 9
#define EXTENT_BUFFER_IN_TREE 10
#define EXTENT_BUFFER_WRITE_ERR 11    /* write IO error */

/* these are flags for extent_clear_unlock_delalloc */
#define PAGE_UNLOCK		(1 << 0)
#define PAGE_CLEAR_DIRTY	(1 << 1)
#define PAGE_SET_WRITEBACK	(1 << 2)
#define PAGE_END_WRITEBACK	(1 << 3)
#define PAGE_SET_PRIVATE2	(1 << 4)
#define PAGE_SET_ERROR		(1 << 5)

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

struct extent_state;
struct btrfs_root;
struct btrfs_io_bio;

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 btrfs_io_bio *io_bio, u64 phy_offset,
				    struct page *page, u64 start, u64 end,
				    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,
			     unsigned *bits);
	void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
			       unsigned *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 address_space *mapping;
	u64 dirty_bytes;
	int track_uptodate;
	spinlock_t lock;
	const struct extent_io_ops *ops;
};

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

	/* ADD NEW ELEMENTS AFTER THIS */
	wait_queue_head_t wq;
	atomic_t refs;
	unsigned 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 bflags;
	struct btrfs_fs_info *fs_info;
	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;
	short lock_nested;
	/* >= 0 if eb belongs to a log tree, -1 otherwise */
	short log_index;

	/* 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;
	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
#ifdef CONFIG_BTRFS_DEBUG
	struct list_head leak_list;
#endif
};

/*
 * Structure to record how many bytes and which ranges are set/cleared
 */
struct extent_changeset {
	/* How many bytes are set/cleared in this operation */
	u64 bytes_changed;

	/* Changed ranges */
	struct ulist *range_changed;
};

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,
		     unsigned 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 extent_read_full_page_nolock(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 bits, int contig);

void free_extent_state(struct extent_state *state);
int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
		   unsigned bits, int filled,
		   struct extent_state *cached_state);
int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
		      unsigned bits, gfp_t mask);
int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
		     unsigned 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,
		    unsigned bits, gfp_t mask);
int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
		   unsigned 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,
		       unsigned bits, unsigned 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, unsigned 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 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 btrfs_fs_info *fs_info,
					  u64 start);
struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
		u64 start);
struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
					 u64 start);
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 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);
int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *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 extent_buffer_under_io(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, u64 start, u64 end,
				 struct page *locked_page,
				 unsigned bits_to_clear,
				 unsigned long page_ops);
struct bio *
btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
		gfp_t gfp_flags);
struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);

struct btrfs_fs_info;

int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
		      struct page *page, unsigned int pg_offset,
		      int mirror_num);
int clean_io_failure(struct inode *inode, u64 start, struct page *page,
		     unsigned int pg_offset);
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);

/*
 * When IO fails, either with EIO or csum verification fails, we
 * try other mirrors that might have a good copy of the data.  This
 * io_failure_record is used to record state as we go through all the
 * mirrors.  If another mirror has good data, the page is set up to date
 * and things continue.  If a good mirror can't be found, the original
 * bio end_io callback is called to indicate things have failed.
 */
struct io_failure_record {
	struct page *page;
	u64 start;
	u64 len;
	u64 logical;
	unsigned long bio_flags;
	int this_mirror;
	int failed_mirror;
	int in_validation;
};

void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
				struct io_failure_record **failrec_ret);
int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
			   struct io_failure_record *failrec, int fail_mirror);
struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
				    struct io_failure_record *failrec,
				    struct page *page, int pg_offset, int icsum,
				    bio_end_io_t *endio_func, void *data);
int free_io_failure(struct inode *inode, struct io_failure_record *rec);
#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
noinline u64 find_lock_delalloc_range(struct inode *inode,
				      struct extent_io_tree *tree,
				      struct page *locked_page, u64 *start,
				      u64 *end, u64 max_bytes);
#endif
struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
					       u64 start);
#endif
Commit	Line	Data
d1310b2e CM	1	#ifndef __EXTENTIO__
	2	#define __EXTENTIO__
	3
	4	#include <linux/rbtree.h>
ac467772	5	#include "ulist.h"
d1310b2e CM	6
d1310b2e CM	7	/* bits for the extent state */
9ee49a04 DS	8	#define EXTENT_DIRTY (1U << 0)
	9	#define EXTENT_WRITEBACK (1U << 1)
	10	#define EXTENT_UPTODATE (1U << 2)
	11	#define EXTENT_LOCKED (1U << 3)
	12	#define EXTENT_NEW (1U << 4)
	13	#define EXTENT_DELALLOC (1U << 5)
	14	#define EXTENT_DEFRAG (1U << 6)
	15	#define EXTENT_BOUNDARY (1U << 9)
	16	#define EXTENT_NODATASUM (1U << 10)
	17	#define EXTENT_DO_ACCOUNTING (1U << 11)
	18	#define EXTENT_FIRST_DELALLOC (1U << 12)
	19	#define EXTENT_NEED_WAIT (1U << 13)
	20	#define EXTENT_DAMAGED (1U << 14)
	21	#define EXTENT_NORESERVE (1U << 15)
	22	#define EXTENT_IOBITS (EXTENT_LOCKED \| EXTENT_WRITEBACK)
	23	#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING \| EXTENT_FIRST_DELALLOC)
d1310b2e	24
261507a0 LZ	25	/*
	26	* flags for bio submission. The high bits indicate the compression
	27	* type for this bio
	28	*/
c8b97818	29	#define EXTENT_BIO_COMPRESSED 1
de0022b9	30	#define EXTENT_BIO_TREE_LOG 2
4b384318	31	#define EXTENT_BIO_PARENT_LOCKED 4
261507a0	32	#define EXTENT_BIO_FLAG_SHIFT 16
c8b97818	33
b4ce94de CM	34	/* these are bit numbers for test/set bit */
b4ce94de CM	35	#define EXTENT_BUFFER_UPTODATE 0
b9473439	36	#define EXTENT_BUFFER_DIRTY 2
a826d6dc	37	#define EXTENT_BUFFER_CORRUPT 3
ab0fff03	38	#define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
3083ee2e JB	39	#define EXTENT_BUFFER_TREE_REF 5
3083ee2e JB	40	#define EXTENT_BUFFER_STALE 6
0b32f4bb	41	#define EXTENT_BUFFER_WRITEBACK 7
656f30db	42	#define EXTENT_BUFFER_READ_ERR 8 /* read IO error */
815a51c7	43	#define EXTENT_BUFFER_DUMMY 9
34b41ace	44	#define EXTENT_BUFFER_IN_TREE 10
656f30db	45	#define EXTENT_BUFFER_WRITE_ERR 11 /* write IO error */
b4ce94de	46
a791e35e	47	/* these are flags for extent_clear_unlock_delalloc */
c2790a2e JB	48	#define PAGE_UNLOCK (1 << 0)
	49	#define PAGE_CLEAR_DIRTY (1 << 1)
	50	#define PAGE_SET_WRITEBACK (1 << 2)
	51	#define PAGE_END_WRITEBACK (1 << 3)
	52	#define PAGE_SET_PRIVATE2 (1 << 4)
704de49d	53	#define PAGE_SET_ERROR (1 << 5)
a791e35e	54
d1310b2e CM	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
d1310b2e	60
70dec807	61	struct extent_state;
ea466794	62	struct btrfs_root;
facc8a22	63	struct btrfs_io_bio;
70dec807	64
44b8bd7e	65	typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
c8b97818	66	struct bio *bio, int mirror_num,
eaf25d93	67	unsigned long bio_flags, u64 bio_offset);
d1310b2e	68	struct extent_io_ops {
c8b97818	69	int (fill_delalloc)(struct inode inode, struct page *locked_page,
771ed689 CM	70	u64 start, u64 end, int *page_started,
771ed689 CM	71	unsigned long *nr_written);
247e743c	72	int (writepage_start_hook)(struct page page, u64 start, u64 end);
d1310b2e	73	int (writepage_io_hook)(struct page page, u64 start, u64 end);
44b8bd7e	74	extent_submit_bio_hook_t *submit_bio_hook;
64a16701	75	int (merge_bio_hook)(int rw, struct page page, unsigned long offset,
c8b97818 CM	76	size_t size, struct bio *bio,
c8b97818 CM	77	unsigned long bio_flags);
ea466794	78	int (readpage_io_failed_hook)(struct page page, int failed_mirror);
facc8a22 MX	79	int (readpage_end_io_hook)(struct btrfs_io_bio io_bio, u64 phy_offset,
	80	struct page *page, u64 start, u64 end,
	81	int mirror);
1259ab75	82	int (writepage_end_io_hook)(struct page page, u64 start, u64 end,
e6dcd2dc	83	struct extent_state *state, int uptodate);
1bf85046	84	void (set_bit_hook)(struct inode inode, struct extent_state *state,
9ee49a04	85	unsigned *bits);
1bf85046	86	void (clear_bit_hook)(struct inode inode, struct extent_state *state,
9ee49a04	87	unsigned *bits);
1bf85046 JM	88	void (merge_extent_hook)(struct inode inode,
	89	struct extent_state *new,
	90	struct extent_state *other);
	91	void (split_extent_hook)(struct inode inode,
	92	struct extent_state *orig, u64 split);
d1310b2e CM	93	};
	94
	95	struct extent_io_tree {
	96	struct rb_root state;
	97	struct address_space *mapping;
	98	u64 dirty_bytes;
0b32f4bb	99	int track_uptodate;
70dec807	100	spinlock_t lock;
e8c9f186	101	const struct extent_io_ops *ops;
d1310b2e CM	102	};
	103
	104	struct extent_state {
	105	u64 start;
	106	u64 end; /* inclusive */
d1310b2e	107	struct rb_node rb_node;
9ed74f2d JB	108
9ed74f2d JB	109	/* ADD NEW ELEMENTS AFTER THIS */
d1310b2e CM	110	wait_queue_head_t wq;
d1310b2e CM	111	atomic_t refs;
9ee49a04	112	unsigned state;
d1310b2e CM	113
	114	/* for use by the FS */
	115	u64 private;
	116
6d49ba1b	117	#ifdef CONFIG_BTRFS_DEBUG
2d2ae547	118	struct list_head leak_list;
6d49ba1b	119	#endif
d1310b2e CM	120	};
d1310b2e CM	121
727011e0 CM	122	#define INLINE_EXTENT_BUFFER_PAGES 16
727011e0 CM	123	#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
d1310b2e CM	124	struct extent_buffer {
	125	u64 start;
	126	unsigned long len;
b4ce94de	127	unsigned long bflags;
f28491e0	128	struct btrfs_fs_info *fs_info;
3083ee2e	129	spinlock_t refs_lock;
727011e0	130	atomic_t refs;
0b32f4bb	131	atomic_t io_pages;
5cf1ab56	132	int read_mirror;
19fe0a8b	133	struct rcu_head rcu_head;
5b25f70f	134	pid_t lock_owner;
b4ce94de	135
bd681513 CM	136	/* count of read lock holders on the extent buffer */
	137	atomic_t write_locks;
	138	atomic_t read_locks;
	139	atomic_t blocking_writers;
	140	atomic_t blocking_readers;
	141	atomic_t spinning_readers;
	142	atomic_t spinning_writers;
656f30db FM	143	short lock_nested;
	144	/* >= 0 if eb belongs to a log tree, -1 otherwise */
	145	short log_index;
bd681513 CM	146
	147	/* protects write locks */
	148	rwlock_t lock;
	149
	150	/* readers use lock_wq while they wait for the write
	151	* lock holders to unlock
	152	*/
	153	wait_queue_head_t write_lock_wq;
b4ce94de	154
bd681513 CM	155	/* writers use read_lock_wq while they wait for readers
bd681513 CM	156	* to unlock
b4ce94de	157	*/
bd681513	158	wait_queue_head_t read_lock_wq;
b8dae313	159	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
6d49ba1b ES	160	#ifdef CONFIG_BTRFS_DEBUG
	161	struct list_head leak_list;
	162	#endif
d1310b2e CM	163	};
d1310b2e CM	164
ac467772 QW	165	/*
	166	* Structure to record how many bytes and which ranges are set/cleared
	167	*/
	168	struct extent_changeset {
	169	/* How many bytes are set/cleared in this operation */
	170	u64 bytes_changed;
	171
	172	/* Changed ranges */
	173	struct ulist *range_changed;
	174	};
	175
261507a0 LZ	176	static inline void extent_set_compress_type(unsigned long *bio_flags,
	177	int compress_type)
	178	{
	179	*bio_flags \|= compress_type << EXTENT_BIO_FLAG_SHIFT;
	180	}
	181
	182	static inline int extent_compress_type(unsigned long bio_flags)
	183	{
	184	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
	185	}
	186
d1310b2e CM	187	struct extent_map_tree;
	188
	189	typedef struct extent_map (get_extent_t)(struct inode inode,
	190	struct page *page,
306e16ce	191	size_t pg_offset,
d1310b2e CM	192	u64 start, u64 len,
	193	int create);
	194
	195	void extent_io_tree_init(struct extent_io_tree *tree,
f993c883	196	struct address_space *mapping);
d1310b2e	197	int try_release_extent_mapping(struct extent_map_tree *map,
70dec807 CM	198	struct extent_io_tree tree, struct page page,
70dec807 CM	199	gfp_t mask);
f7a52a40	200	int try_release_extent_buffer(struct page *page);
d0082371	201	int lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
1edbb734	202	int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	203	unsigned bits, struct extent_state **cached);
d0082371	204	int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end);
2ac55d41 JB	205	int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
2ac55d41 JB	206	struct extent_state **cached, gfp_t mask);
d0082371	207	int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
d1310b2e	208	int extent_read_full_page(struct extent_io_tree tree, struct page page,
8ddc7d9c	209	get_extent_t *get_extent, int mirror_num);
4b384318 MF	210	int extent_read_full_page_nolock(struct extent_io_tree tree, struct page page,
4b384318 MF	211	get_extent_t *get_extent, int mirror_num);
d1310b2e CM	212	int __init extent_io_init(void);
	213	void extent_io_exit(void);
	214
	215	u64 count_range_bits(struct extent_io_tree *tree,
	216	u64 *start, u64 search_end,
9ee49a04	217	u64 max_bytes, unsigned bits, int contig);
d1310b2e	218
4845e44f	219	void free_extent_state(struct extent_state *state);
d1310b2e	220	int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	221	unsigned bits, int filled,
41074888	222	struct extent_state *cached_state);
d1310b2e	223	int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	224	unsigned bits, gfp_t mask);
e6dcd2dc	225	int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	226	unsigned bits, int wake, int delete,
41074888	227	struct extent_state **cached, gfp_t mask);
d1310b2e	228	int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	229	unsigned bits, gfp_t mask);
4845e44f	230	int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	231	unsigned bits, u64 *failed_start,
4845e44f	232	struct extent_state **cached_state, gfp_t mask);
d1310b2e	233	int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
507903b8	234	struct extent_state **cached_state, gfp_t mask);
5fd02043 JB	235	int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
5fd02043 JB	236	struct extent_state **cached_state, gfp_t mask);
d1310b2e CM	237	int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
	238	gfp_t mask);
	239	int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
	240	gfp_t mask);
	241	int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
	242	gfp_t mask);
462d6fac	243	int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
9ee49a04	244	unsigned bits, unsigned clear_bits,
e6138876	245	struct extent_state **cached_state, gfp_t mask);
d1310b2e	246	int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
2ac55d41	247	struct extent_state **cached_state, gfp_t mask);
9e8a4a8b LB	248	int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
9e8a4a8b LB	249	struct extent_state **cached_state, gfp_t mask);
d1310b2e	250	int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
9ee49a04	251	u64 start_ret, u64 end_ret, unsigned bits,
e6138876	252	struct extent_state **cached_state);
d1310b2e CM	253	int extent_invalidatepage(struct extent_io_tree *tree,
	254	struct page *page, unsigned long offset);
	255	int extent_write_full_page(struct extent_io_tree tree, struct page page,
	256	get_extent_t *get_extent,
	257	struct writeback_control *wbc);
771ed689 CM	258	int extent_write_locked_range(struct extent_io_tree tree, struct inode inode,
	259	u64 start, u64 end, get_extent_t *get_extent,
	260	int mode);
d1310b2e CM	261	int extent_writepages(struct extent_io_tree *tree,
	262	struct address_space *mapping,
	263	get_extent_t *get_extent,
	264	struct writeback_control *wbc);
0b32f4bb JB	265	int btree_write_cache_pages(struct address_space *mapping,
0b32f4bb JB	266	struct writeback_control *wbc);
d1310b2e CM	267	int extent_readpages(struct extent_io_tree *tree,
	268	struct address_space *mapping,
	269	struct list_head *pages, unsigned nr_pages,
	270	get_extent_t get_extent);
1506fcc8 YS	271	int extent_fiemap(struct inode inode, struct fiemap_extent_info fieinfo,
1506fcc8 YS	272	__u64 start, __u64 len, get_extent_t *get_extent);
d1310b2e CM	273	int get_state_private(struct extent_io_tree tree, u64 start, u64 private);
	274	void set_page_extent_mapped(struct page *page);
	275
f28491e0	276	struct extent_buffer alloc_extent_buffer(struct btrfs_fs_info fs_info,
ce3e6984	277	u64 start);
3f556f78 DS	278	struct extent_buffer alloc_dummy_extent_buffer(struct btrfs_fs_info fs_info,
3f556f78 DS	279	u64 start);
815a51c7	280	struct extent_buffer btrfs_clone_extent_buffer(struct extent_buffer src);
f28491e0	281	struct extent_buffer find_extent_buffer(struct btrfs_fs_info fs_info,
452c75c3	282	u64 start);
d1310b2e	283	void free_extent_buffer(struct extent_buffer *eb);
3083ee2e	284	void free_extent_buffer_stale(struct extent_buffer *eb);
bb82ab88 AJ	285	#define WAIT_NONE 0
	286	#define WAIT_COMPLETE 1
	287	#define WAIT_PAGE_LOCK 2
d1310b2e	288	int read_extent_buffer_pages(struct extent_io_tree *tree,
a86c12c7	289	struct extent_buffer *eb, u64 start, int wait,
f188591e	290	get_extent_t *get_extent, int mirror_num);
fd8b2b61	291	void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
479ed9ab RD	292
	293	static inline unsigned long num_extent_pages(u64 start, u64 len)
	294	{
	295	return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
	296	(start >> PAGE_CACHE_SHIFT);
	297	}
	298
d1310b2e CM	299	static inline void extent_buffer_get(struct extent_buffer *eb)
	300	{
	301	atomic_inc(&eb->refs);
	302	}
	303
	304	int memcmp_extent_buffer(struct extent_buffer eb, const void ptrv,
	305	unsigned long start,
	306	unsigned long len);
	307	void read_extent_buffer(struct extent_buffer eb, void dst,
	308	unsigned long start,
	309	unsigned long len);
550ac1d8 GH	310	int read_extent_buffer_to_user(struct extent_buffer eb, void __user dst,
	311	unsigned long start,
	312	unsigned long len);
d1310b2e CM	313	void write_extent_buffer(struct extent_buffer eb, const void src,
	314	unsigned long start, unsigned long len);
	315	void copy_extent_buffer(struct extent_buffer dst, struct extent_buffer src,
	316	unsigned long dst_offset, unsigned long src_offset,
	317	unsigned long len);
	318	void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
	319	unsigned long src_offset, unsigned long len);
	320	void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
	321	unsigned long src_offset, unsigned long len);
	322	void memset_extent_buffer(struct extent_buffer *eb, char c,
	323	unsigned long start, unsigned long len);
1d4284bd	324	void clear_extent_buffer_dirty(struct extent_buffer *eb);
0b32f4bb JB	325	int set_extent_buffer_dirty(struct extent_buffer *eb);
	326	int set_extent_buffer_uptodate(struct extent_buffer *eb);
	327	int clear_extent_buffer_uptodate(struct extent_buffer *eb);
	328	int extent_buffer_uptodate(struct extent_buffer *eb);
a26e8c9f	329	int extent_buffer_under_io(struct extent_buffer *eb);
d1310b2e	330	int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
a6591715	331	unsigned long min_len, char **map,
d1310b2e	332	unsigned long *map_start,
a6591715	333	unsigned long *map_len);
4adaa611 CM	334	int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
4adaa611 CM	335	int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
c2790a2e JB	336	int extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
c2790a2e JB	337	struct page *locked_page,
9ee49a04	338	unsigned bits_to_clear,
c2790a2e	339	unsigned long page_ops);
88f794ed MX	340	struct bio *
	341	btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
	342	gfp_t gfp_flags);
9be3395b CM	343	struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
9be3395b CM	344	struct bio btrfs_bio_clone(struct bio bio, gfp_t gfp_mask);
4a54c8c1	345
3ec706c8	346	struct btrfs_fs_info;
4a54c8c1	347
1203b681 MX	348	int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
	349	struct page *page, unsigned int pg_offset,
	350	int mirror_num);
8b110e39 MX	351	int clean_io_failure(struct inode inode, u64 start, struct page page,
8b110e39 MX	352	unsigned int pg_offset);
87826df0	353	int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
ea466794 JB	354	int repair_eb_io_failure(struct btrfs_root root, struct extent_buffer eb,
ea466794 JB	355	int mirror_num);
2fe6303e MX	356
	357	/*
	358	* When IO fails, either with EIO or csum verification fails, we
	359	* try other mirrors that might have a good copy of the data. This
	360	* io_failure_record is used to record state as we go through all the
	361	* mirrors. If another mirror has good data, the page is set up to date
	362	* and things continue. If a good mirror can't be found, the original
	363	* bio end_io callback is called to indicate things have failed.
	364	*/
	365	struct io_failure_record {
	366	struct page *page;
	367	u64 start;
	368	u64 len;
	369	u64 logical;
	370	unsigned long bio_flags;
	371	int this_mirror;
	372	int failed_mirror;
	373	int in_validation;
	374	};
	375
f612496b	376	void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
2fe6303e MX	377	int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
	378	struct io_failure_record **failrec_ret);
	379	int btrfs_check_repairable(struct inode inode, struct bio failed_bio,
	380	struct io_failure_record *failrec, int fail_mirror);
	381	struct bio btrfs_create_repair_bio(struct inode inode, struct bio *failed_bio,
	382	struct io_failure_record *failrec,
	383	struct page *page, int pg_offset, int icsum,
8b110e39 MX	384	bio_end_io_t endio_func, void data);
8b110e39 MX	385	int free_io_failure(struct inode inode, struct io_failure_record rec);
294e30fe JB	386	#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
	387	noinline u64 find_lock_delalloc_range(struct inode *inode,
	388	struct extent_io_tree *tree,
	389	struct page locked_page, u64 start,
	390	u64 *end, u64 max_bytes);
0d4cf4e6	391	#endif
faa2dbf0	392	struct extent_buffer alloc_test_extent_buffer(struct btrfs_fs_info fs_info,
ce3e6984	393	u64 start);
294e30fe	394	#endif