[linux-2.6-block.git] / fs / btrfs / compression.h

/*
 * Copyright (C) 2008 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 __BTRFS_COMPRESSION_
#define __BTRFS_COMPRESSION_

void btrfs_init_compress(void);
void btrfs_exit_compress(void);

int btrfs_compress_pages(int type, struct address_space *mapping,
			 u64 start, unsigned long len,
			 struct page **pages,
			 unsigned long nr_dest_pages,
			 unsigned long *out_pages,
			 unsigned long *total_in,
			 unsigned long *total_out,
			 unsigned long max_out);
int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
		     unsigned long start_byte, size_t srclen, size_t destlen);
int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
			      unsigned long total_out, u64 disk_start,
			      struct bio_vec *bvec, int vcnt,
			      unsigned long *pg_index,
			      unsigned long *pg_offset);

int btrfs_submit_compressed_write(struct inode *inode, u64 start,
				  unsigned long len, u64 disk_start,
				  unsigned long compressed_len,
				  struct page **compressed_pages,
				  unsigned long nr_pages);
int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
				 int mirror_num, unsigned long bio_flags);
void btrfs_clear_biovec_end(struct bio_vec *bvec, int vcnt,
				   unsigned long pg_index,
				   unsigned long pg_offset);

enum btrfs_compression_type {
	BTRFS_COMPRESS_NONE  = 0,
	BTRFS_COMPRESS_ZLIB  = 1,
	BTRFS_COMPRESS_LZO   = 2,
	BTRFS_COMPRESS_TYPES = 2,
	BTRFS_COMPRESS_LAST  = 3,
};

struct btrfs_compress_op {
	struct list_head *(*alloc_workspace)(void);

	void (*free_workspace)(struct list_head *workspace);

	int (*compress_pages)(struct list_head *workspace,
			      struct address_space *mapping,
			      u64 start, unsigned long len,
			      struct page **pages,
			      unsigned long nr_dest_pages,
			      unsigned long *out_pages,
			      unsigned long *total_in,
			      unsigned long *total_out,
			      unsigned long max_out);

	int (*decompress_biovec)(struct list_head *workspace,
				 struct page **pages_in,
				 u64 disk_start,
				 struct bio_vec *bvec,
				 int vcnt,
				 size_t srclen);

	int (*decompress)(struct list_head *workspace,
			  unsigned char *data_in,
			  struct page *dest_page,
			  unsigned long start_byte,
			  size_t srclen, size_t destlen);
};

extern const struct btrfs_compress_op btrfs_zlib_compress;
extern const struct btrfs_compress_op btrfs_lzo_compress;

#endif
Commit	Line	Data
c8b97818 CM	1	/*
	2	* Copyright (C) 2008 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 __BTRFS_COMPRESSION_
	20	#define __BTRFS_COMPRESSION_
	21
143bede5	22	void btrfs_init_compress(void);
261507a0 LZ	23	void btrfs_exit_compress(void);
	24
	25	int btrfs_compress_pages(int type, struct address_space *mapping,
	26	u64 start, unsigned long len,
	27	struct page **pages,
	28	unsigned long nr_dest_pages,
	29	unsigned long *out_pages,
	30	unsigned long *total_in,
	31	unsigned long *total_out,
	32	unsigned long max_out);
261507a0 LZ	33	int btrfs_decompress(int type, unsigned char data_in, struct page dest_page,
261507a0 LZ	34	unsigned long start_byte, size_t srclen, size_t destlen);
3a39c18d LZ	35	int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
	36	unsigned long total_out, u64 disk_start,
	37	struct bio_vec *bvec, int vcnt,
306e16ce	38	unsigned long *pg_index,
3a39c18d	39	unsigned long *pg_offset);
261507a0	40
c8b97818 CM	41	int btrfs_submit_compressed_write(struct inode *inode, u64 start,
	42	unsigned long len, u64 disk_start,
	43	unsigned long compressed_len,
	44	struct page **compressed_pages,
	45	unsigned long nr_pages);
	46	int btrfs_submit_compressed_read(struct inode inode, struct bio bio,
	47	int mirror_num, unsigned long bio_flags);
2f19cad9 CM	48	void btrfs_clear_biovec_end(struct bio_vec *bvec, int vcnt,
	49	unsigned long pg_index,
	50	unsigned long pg_offset);
ebb8765b AJ	51
	52	enum btrfs_compression_type {
	53	BTRFS_COMPRESS_NONE = 0,
	54	BTRFS_COMPRESS_ZLIB = 1,
	55	BTRFS_COMPRESS_LZO = 2,
	56	BTRFS_COMPRESS_TYPES = 2,
	57	BTRFS_COMPRESS_LAST = 3,
	58	};
	59
261507a0 LZ	60	struct btrfs_compress_op {
	61	struct list_head (alloc_workspace)(void);
	62
	63	void (free_workspace)(struct list_head workspace);
	64
	65	int (compress_pages)(struct list_head workspace,
	66	struct address_space *mapping,
	67	u64 start, unsigned long len,
	68	struct page **pages,
	69	unsigned long nr_dest_pages,
	70	unsigned long *out_pages,
	71	unsigned long *total_in,
	72	unsigned long *total_out,
	73	unsigned long max_out);
	74
	75	int (decompress_biovec)(struct list_head workspace,
	76	struct page **pages_in,
	77	u64 disk_start,
	78	struct bio_vec *bvec,
	79	int vcnt,
	80	size_t srclen);
	81
	82	int (decompress)(struct list_head workspace,
	83	unsigned char *data_in,
	84	struct page *dest_page,
	85	unsigned long start_byte,
	86	size_t srclen, size_t destlen);
	87	};
	88
e8c9f186 DS	89	extern const struct btrfs_compress_op btrfs_zlib_compress;
e8c9f186 DS	90	extern const struct btrfs_compress_op btrfs_lzo_compress;
261507a0	91
c8b97818	92	#endif