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9888c340 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
c8b97818 CM |
2 | /* |
3 | * Copyright (C) 2008 Oracle. All rights reserved. | |
c8b97818 CM |
4 | */ |
5 | ||
9888c340 DS |
6 | #ifndef BTRFS_COMPRESSION_H |
7 | #define BTRFS_COMPRESSION_H | |
c8b97818 | 8 | |
ff763866 DS |
9 | /* |
10 | * We want to make sure that amount of RAM required to uncompress an extent is | |
11 | * reasonable, so we limit the total size in ram of a compressed extent to | |
12 | * 128k. This is a crucial number because it also controls how easily we can | |
13 | * spread reads across cpus for decompression. | |
14 | * | |
15 | * We also want to make sure the amount of IO required to do a random read is | |
16 | * reasonably small, so we limit the size of a compressed extent to 128k. | |
17 | */ | |
18 | ||
19 | /* Maximum length of compressed data stored on disk */ | |
20 | #define BTRFS_MAX_COMPRESSED (SZ_128K) | |
21 | /* Maximum size of data before compression */ | |
22 | #define BTRFS_MAX_UNCOMPRESSED (SZ_128K) | |
23 | ||
eae8d825 QW |
24 | #define BTRFS_ZLIB_DEFAULT_LEVEL 3 |
25 | ||
e1ddce71 AJ |
26 | struct compressed_bio { |
27 | /* number of bios pending for this compressed extent */ | |
28 | refcount_t pending_bios; | |
29 | ||
30 | /* the pages with the compressed data on them */ | |
31 | struct page **compressed_pages; | |
32 | ||
33 | /* inode that owns this data */ | |
34 | struct inode *inode; | |
35 | ||
36 | /* starting offset in the inode for our pages */ | |
37 | u64 start; | |
38 | ||
39 | /* number of bytes in the inode we're working on */ | |
40 | unsigned long len; | |
41 | ||
42 | /* number of bytes on disk */ | |
43 | unsigned long compressed_len; | |
44 | ||
45 | /* the compression algorithm for this bio */ | |
46 | int compress_type; | |
47 | ||
48 | /* number of compressed pages in the array */ | |
49 | unsigned long nr_pages; | |
50 | ||
51 | /* IO errors */ | |
52 | int errors; | |
53 | int mirror_num; | |
54 | ||
55 | /* for reads, this is the bio we are copying the data into */ | |
56 | struct bio *orig_bio; | |
57 | ||
58 | /* | |
59 | * the start of a variable length array of checksums only | |
60 | * used by reads | |
61 | */ | |
62 | u32 sums; | |
63 | }; | |
64 | ||
f5c29bd9 | 65 | void __init btrfs_init_compress(void); |
e67c718b | 66 | void __cold btrfs_exit_compress(void); |
261507a0 | 67 | |
f51d2b59 | 68 | int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping, |
38c31464 | 69 | u64 start, struct page **pages, |
261507a0 LZ |
70 | unsigned long *out_pages, |
71 | unsigned long *total_in, | |
e5d74902 | 72 | unsigned long *total_out); |
261507a0 LZ |
73 | int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page, |
74 | unsigned long start_byte, size_t srclen, size_t destlen); | |
14a3357b | 75 | int btrfs_decompress_buf2page(const char *buf, unsigned long buf_start, |
3a39c18d | 76 | unsigned long total_out, u64 disk_start, |
974b1adc | 77 | struct bio *bio); |
261507a0 | 78 | |
4e4cbee9 | 79 | blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start, |
c8b97818 CM |
80 | unsigned long len, u64 disk_start, |
81 | unsigned long compressed_len, | |
82 | struct page **compressed_pages, | |
f82b7359 LB |
83 | unsigned long nr_pages, |
84 | unsigned int write_flags); | |
4e4cbee9 | 85 | blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, |
c8b97818 | 86 | int mirror_num, unsigned long bio_flags); |
ebb8765b | 87 | |
f51d2b59 DS |
88 | unsigned btrfs_compress_str2level(const char *str); |
89 | ||
ebb8765b AJ |
90 | enum btrfs_compression_type { |
91 | BTRFS_COMPRESS_NONE = 0, | |
92 | BTRFS_COMPRESS_ZLIB = 1, | |
93 | BTRFS_COMPRESS_LZO = 2, | |
5c1aab1d NT |
94 | BTRFS_COMPRESS_ZSTD = 3, |
95 | BTRFS_COMPRESS_TYPES = 3, | |
ebb8765b AJ |
96 | }; |
97 | ||
261507a0 LZ |
98 | struct btrfs_compress_op { |
99 | struct list_head *(*alloc_workspace)(void); | |
100 | ||
101 | void (*free_workspace)(struct list_head *workspace); | |
102 | ||
103 | int (*compress_pages)(struct list_head *workspace, | |
104 | struct address_space *mapping, | |
38c31464 | 105 | u64 start, |
261507a0 | 106 | struct page **pages, |
261507a0 LZ |
107 | unsigned long *out_pages, |
108 | unsigned long *total_in, | |
e5d74902 | 109 | unsigned long *total_out); |
261507a0 | 110 | |
974b1adc | 111 | int (*decompress_bio)(struct list_head *workspace, |
e1ddce71 | 112 | struct compressed_bio *cb); |
261507a0 LZ |
113 | |
114 | int (*decompress)(struct list_head *workspace, | |
115 | unsigned char *data_in, | |
116 | struct page *dest_page, | |
117 | unsigned long start_byte, | |
118 | size_t srclen, size_t destlen); | |
f51d2b59 DS |
119 | |
120 | void (*set_level)(struct list_head *ws, unsigned int type); | |
261507a0 LZ |
121 | }; |
122 | ||
e8c9f186 DS |
123 | extern const struct btrfs_compress_op btrfs_zlib_compress; |
124 | extern const struct btrfs_compress_op btrfs_lzo_compress; | |
5c1aab1d | 125 | extern const struct btrfs_compress_op btrfs_zstd_compress; |
261507a0 | 126 | |
e128f9c3 DS |
127 | const char* btrfs_compress_type2str(enum btrfs_compression_type type); |
128 | ||
c2fcdcdf TT |
129 | int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end); |
130 | ||
c8b97818 | 131 | #endif |