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 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 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 89 extern const struct btrfs_compress_op btrfs_zlib_compress; 90 extern const struct btrfs_compress_op btrfs_lzo_compress; 91 92 #endif 93