[deliverable/linux.git] / fs / btrfs / disk-io.h

/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#ifndef __DISKIO__
#define __DISKIO__

#define BTRFS_SUPER_INFO_OFFSET SZ_64K
#define BTRFS_SUPER_INFO_SIZE 4096

#define BTRFS_SUPER_MIRROR_MAX	 3
#define BTRFS_SUPER_MIRROR_SHIFT 12

enum btrfs_wq_endio_type {
	BTRFS_WQ_ENDIO_DATA = 0,
	BTRFS_WQ_ENDIO_METADATA = 1,
	BTRFS_WQ_ENDIO_FREE_SPACE = 2,
	BTRFS_WQ_ENDIO_RAID56 = 3,
	BTRFS_WQ_ENDIO_DIO_REPAIR = 4,
};

static inline u64 btrfs_sb_offset(int mirror)
{
	u64 start = SZ_16K;
	if (mirror)
		return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
	return BTRFS_SUPER_INFO_OFFSET;
}

struct btrfs_device;
struct btrfs_fs_devices;

struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
				      u64 parent_transid);
void readahead_tree_block(struct btrfs_root *root, u64 bytenr);
int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr,
			 int mirror_num, struct extent_buffer **eb);
struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
						   u64 bytenr);
void clean_tree_block(struct btrfs_trans_handle *trans,
		      struct btrfs_fs_info *fs_info, struct extent_buffer *buf);
int open_ctree(struct super_block *sb,
	       struct btrfs_fs_devices *fs_devices,
	       char *options);
void close_ctree(struct btrfs_root *root);
int write_ctree_super(struct btrfs_trans_handle *trans,
		      struct btrfs_root *root, int max_mirrors);
struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
			struct buffer_head **bh_ret);
int btrfs_commit_super(struct btrfs_root *root);
struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
					    u64 bytenr);
struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
				      struct btrfs_key *location);
int btrfs_init_fs_root(struct btrfs_root *root);
int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
			 struct btrfs_root *root);
void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);

struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
				     struct btrfs_key *key,
				     bool check_ref);
static inline struct btrfs_root *
btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
			   struct btrfs_key *location)
{
	return btrfs_get_fs_root(fs_info, location, true);
}

int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
void btrfs_btree_balance_dirty(struct btrfs_root *root);
void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root);
void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
				 struct btrfs_root *root);
void btrfs_free_fs_root(struct btrfs_root *root);

#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
struct btrfs_root *btrfs_alloc_dummy_root(void);
#endif

/*
 * This function is used to grab the root, and avoid it is freed when we
 * access it. But it doesn't ensure that the tree is not dropped.
 *
 * If you want to ensure the whole tree is safe, you should use
 * 	fs_info->subvol_srcu
 */
static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root)
{
	if (atomic_inc_not_zero(&root->refs))
		return root;
	return NULL;
}

static inline void btrfs_put_fs_root(struct btrfs_root *root)
{
	if (atomic_dec_and_test(&root->refs))
		kfree(root);
}

void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
			  int atomic);
int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
u32 btrfs_csum_data(char *data, u32 seed, size_t len);
void btrfs_csum_final(u32 crc, char *result);
int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
			enum btrfs_wq_endio_type metadata);
int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
			int rw, struct bio *bio, int mirror_num,
			unsigned long bio_flags, u64 bio_offset,
			extent_submit_bio_hook_t *submit_bio_start,
			extent_submit_bio_hook_t *submit_bio_done);
unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info);
int btrfs_write_tree_block(struct extent_buffer *buf);
int btrfs_wait_tree_block_writeback(struct extent_buffer *buf);
int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
			     struct btrfs_fs_info *fs_info);
int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
		       struct btrfs_root *root);
void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
				  struct btrfs_root *root);
struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
				     struct btrfs_fs_info *fs_info,
				     u64 objectid);
int btree_lock_page_hook(struct page *page, void *data,
				void (*flush_fn)(void *));
int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
int btrfs_calc_num_tolerated_disk_barrier_failures(
	struct btrfs_fs_info *fs_info);
int __init btrfs_end_io_wq_init(void);
void btrfs_end_io_wq_exit(void);

#ifdef CONFIG_DEBUG_LOCK_ALLOC
void btrfs_init_lockdep(void);
void btrfs_set_buffer_lockdep_class(u64 objectid,
			            struct extent_buffer *eb, int level);
#else
static inline void btrfs_init_lockdep(void)
{ }
static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
					struct extent_buffer *eb, int level)
{
}
#endif
#endif
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2007 Oracle. All rights reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public
	6	* License v2 as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	11	* General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public
	14	* License along with this program; if not, write to the
	15	* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	16	* Boston, MA 021110-1307, USA.
	17	*/
	18
	19	#ifndef __DISKIO__
	20	#define __DISKIO__
	21
	22	#define BTRFS_SUPER_INFO_OFFSET SZ_64K
	23	#define BTRFS_SUPER_INFO_SIZE 4096
	24
	25	#define BTRFS_SUPER_MIRROR_MAX 3
	26	#define BTRFS_SUPER_MIRROR_SHIFT 12
	27
	28	enum btrfs_wq_endio_type {
	29	BTRFS_WQ_ENDIO_DATA = 0,
	30	BTRFS_WQ_ENDIO_METADATA = 1,
	31	BTRFS_WQ_ENDIO_FREE_SPACE = 2,
	32	BTRFS_WQ_ENDIO_RAID56 = 3,
	33	BTRFS_WQ_ENDIO_DIO_REPAIR = 4,
	34	};
	35
	36	static inline u64 btrfs_sb_offset(int mirror)
	37	{
	38	u64 start = SZ_16K;
	39	if (mirror)
	40	return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
	41	return BTRFS_SUPER_INFO_OFFSET;
	42	}
	43
	44	struct btrfs_device;
	45	struct btrfs_fs_devices;
	46
	47	struct extent_buffer read_tree_block(struct btrfs_root root, u64 bytenr,
	48	u64 parent_transid);
	49	void readahead_tree_block(struct btrfs_root *root, u64 bytenr);
	50	int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr,
	51	int mirror_num, struct extent_buffer **eb);
	52	struct extent_buffer btrfs_find_create_tree_block(struct btrfs_root root,
	53	u64 bytenr);
	54	void clean_tree_block(struct btrfs_trans_handle *trans,
	55	struct btrfs_fs_info fs_info, struct extent_buffer buf);
	56	int open_ctree(struct super_block *sb,
	57	struct btrfs_fs_devices *fs_devices,
	58	char *options);
	59	void close_ctree(struct btrfs_root *root);
	60	int write_ctree_super(struct btrfs_trans_handle *trans,
	61	struct btrfs_root *root, int max_mirrors);
	62	struct buffer_head btrfs_read_dev_super(struct block_device bdev);
	63	int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
	64	struct buffer_head **bh_ret);
	65	int btrfs_commit_super(struct btrfs_root *root);
	66	struct extent_buffer btrfs_find_tree_block(struct btrfs_fs_info fs_info,
	67	u64 bytenr);
	68	struct btrfs_root btrfs_read_fs_root(struct btrfs_root tree_root,
	69	struct btrfs_key *location);
	70	int btrfs_init_fs_root(struct btrfs_root *root);
	71	int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
	72	struct btrfs_root *root);
	73	void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
	74
	75	struct btrfs_root btrfs_get_fs_root(struct btrfs_fs_info fs_info,
	76	struct btrfs_key *key,
	77	bool check_ref);
	78	static inline struct btrfs_root *
	79	btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
	80	struct btrfs_key *location)
	81	{
	82	return btrfs_get_fs_root(fs_info, location, true);
	83	}
	84
	85	int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
	86	void btrfs_btree_balance_dirty(struct btrfs_root *root);
	87	void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root);
	88	void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
	89	struct btrfs_root *root);
	90	void btrfs_free_fs_root(struct btrfs_root *root);
	91
	92	#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
	93	struct btrfs_root *btrfs_alloc_dummy_root(void);
	94	#endif
	95
	96	/*
	97	* This function is used to grab the root, and avoid it is freed when we
	98	* access it. But it doesn't ensure that the tree is not dropped.
	99	*
	100	* If you want to ensure the whole tree is safe, you should use
	101	* fs_info->subvol_srcu
	102	*/
	103	static inline struct btrfs_root btrfs_grab_fs_root(struct btrfs_root root)
	104	{
	105	if (atomic_inc_not_zero(&root->refs))
	106	return root;
	107	return NULL;
	108	}
	109
	110	static inline void btrfs_put_fs_root(struct btrfs_root *root)
	111	{
	112	if (atomic_dec_and_test(&root->refs))
	113	kfree(root);
	114	}
	115
	116	void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
	117	int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
	118	int atomic);
	119	int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
	120	u32 btrfs_csum_data(char *data, u32 seed, size_t len);
	121	void btrfs_csum_final(u32 crc, char *result);
	122	int btrfs_bio_wq_end_io(struct btrfs_fs_info info, struct bio bio,
	123	enum btrfs_wq_endio_type metadata);
	124	int btrfs_wq_submit_bio(struct btrfs_fs_info fs_info, struct inode inode,
	125	int rw, struct bio *bio, int mirror_num,
	126	unsigned long bio_flags, u64 bio_offset,
	127	extent_submit_bio_hook_t *submit_bio_start,
	128	extent_submit_bio_hook_t *submit_bio_done);
	129	unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info);
	130	int btrfs_write_tree_block(struct extent_buffer *buf);
	131	int btrfs_wait_tree_block_writeback(struct extent_buffer *buf);
	132	int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
	133	struct btrfs_fs_info *fs_info);
	134	int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
	135	struct btrfs_root *root);
	136	void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
	137	struct btrfs_root *root);
	138	struct btrfs_root btrfs_create_tree(struct btrfs_trans_handle trans,
	139	struct btrfs_fs_info *fs_info,
	140	u64 objectid);
	141	int btree_lock_page_hook(struct page page, void data,
	142	void (flush_fn)(void ));
	143	int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
	144	int btrfs_calc_num_tolerated_disk_barrier_failures(
	145	struct btrfs_fs_info *fs_info);
	146	int __init btrfs_end_io_wq_init(void);
	147	void btrfs_end_io_wq_exit(void);
	148
	149	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	150	void btrfs_init_lockdep(void);
	151	void btrfs_set_buffer_lockdep_class(u64 objectid,
	152	struct extent_buffer *eb, int level);
	153	#else
	154	static inline void btrfs_init_lockdep(void)
	155	{ }
	156	static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
	157	struct extent_buffer *eb, int level)
	158	{
	159	}
	160	#endif
	161	#endif