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 22 void btrfs_init_compress(void); 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); 33 int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page, 34 unsigned long start_byte, size_t srclen, size_t destlen); 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, 38 unsigned long *pg_index, 39 unsigned long *pg_offset); 40 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); 48 void btrfs_clear_biovec_end(struct bio_vec *bvec, int vcnt, 49 unsigned long pg_index, 50 unsigned long pg_offset); 51 struct btrfs_compress_op { 52 struct list_head *(*alloc_workspace)(void); 53 54 void (*free_workspace)(struct list_head *workspace); 55 56 int (*compress_pages)(struct list_head *workspace, 57 struct address_space *mapping, 58 u64 start, unsigned long len, 59 struct page **pages, 60 unsigned long nr_dest_pages, 61 unsigned long *out_pages, 62 unsigned long *total_in, 63 unsigned long *total_out, 64 unsigned long max_out); 65 66 int (*decompress_biovec)(struct list_head *workspace, 67 struct page **pages_in, 68 u64 disk_start, 69 struct bio_vec *bvec, 70 int vcnt, 71 size_t srclen); 72 73 int (*decompress)(struct list_head *workspace, 74 unsigned char *data_in, 75 struct page *dest_page, 76 unsigned long start_byte, 77 size_t srclen, size_t destlen); 78 }; 79 80 extern const struct btrfs_compress_op btrfs_zlib_compress; 81 extern const struct btrfs_compress_op btrfs_lzo_compress; 82 83 #endif 84