mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-17 09:14:19 +08:00
4d3a800ebb
The parameter saying how many pages can be allocated at maximum can be merged with the output page counter, to save some stack space. The compression implementation will sink the parameter to a local variable so everything works as before. The nr_pages variables can also be simply merged in compress_file_range into one. Signed-off-by: David Sterba <dsterba@suse.com>
84 lines
2.6 KiB
C
84 lines
2.6 KiB
C
/*
|
|
* 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, struct page **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(const char *buf, unsigned long buf_start,
|
|
unsigned long total_out, u64 disk_start,
|
|
struct bio *bio);
|
|
|
|
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);
|
|
|
|
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,
|
|
struct page **pages,
|
|
unsigned long *out_pages,
|
|
unsigned long *total_in,
|
|
unsigned long *total_out,
|
|
unsigned long max_out);
|
|
|
|
int (*decompress_bio)(struct list_head *workspace,
|
|
struct page **pages_in,
|
|
u64 disk_start,
|
|
struct bio *orig_bio,
|
|
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
|