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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
22int btrfs_init_compress(void);
23void btrfs_exit_compress(void);
24
25int 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);
33int btrfs_decompress_biovec(int type, struct page **pages_in, u64 disk_start,
34 struct bio_vec *bvec, int vcnt, size_t srclen);
35int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
36 unsigned long start_byte, size_t srclen, size_t destlen);
37int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
38 unsigned long total_out, u64 disk_start,
39 struct bio_vec *bvec, int vcnt,
40 unsigned long *pg_index,
41 unsigned long *pg_offset);
42
43int btrfs_submit_compressed_write(struct inode *inode, u64 start,
44 unsigned long len, u64 disk_start,
45 unsigned long compressed_len,
46 struct page **compressed_pages,
47 unsigned long nr_pages);
48int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
49 int mirror_num, unsigned long bio_flags);
50
51struct 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
80extern struct btrfs_compress_op btrfs_zlib_compress;
81extern struct btrfs_compress_op btrfs_lzo_compress;
82
83#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2008 Oracle. All rights reserved.
4 */
5
6#ifndef BTRFS_COMPRESSION_H
7#define BTRFS_COMPRESSION_H
8
9#include <linux/sizes.h>
10#include <linux/mm.h>
11#include <linux/list.h>
12#include <linux/workqueue.h>
13#include <linux/wait.h>
14#include "bio.h"
15
16struct address_space;
17struct page;
18struct inode;
19struct btrfs_inode;
20struct btrfs_ordered_extent;
21struct btrfs_bio;
22
23/*
24 * We want to make sure that amount of RAM required to uncompress an extent is
25 * reasonable, so we limit the total size in ram of a compressed extent to
26 * 128k. This is a crucial number because it also controls how easily we can
27 * spread reads across cpus for decompression.
28 *
29 * We also want to make sure the amount of IO required to do a random read is
30 * reasonably small, so we limit the size of a compressed extent to 128k.
31 */
32
33/* Maximum length of compressed data stored on disk */
34#define BTRFS_MAX_COMPRESSED (SZ_128K)
35#define BTRFS_MAX_COMPRESSED_PAGES (BTRFS_MAX_COMPRESSED / PAGE_SIZE)
36static_assert((BTRFS_MAX_COMPRESSED % PAGE_SIZE) == 0);
37
38/* Maximum size of data before compression */
39#define BTRFS_MAX_UNCOMPRESSED (SZ_128K)
40
41#define BTRFS_ZLIB_DEFAULT_LEVEL 3
42
43struct compressed_bio {
44 /* Number of compressed pages in the array */
45 unsigned int nr_pages;
46
47 /* the pages with the compressed data on them */
48 struct page **compressed_pages;
49
50 /* starting offset in the inode for our pages */
51 u64 start;
52
53 /* Number of bytes in the inode we're working on */
54 unsigned int len;
55
56 /* Number of bytes on disk */
57 unsigned int compressed_len;
58
59 /* The compression algorithm for this bio */
60 u8 compress_type;
61
62 /* Whether this is a write for writeback. */
63 bool writeback;
64
65 union {
66 /* For reads, this is the bio we are copying the data into */
67 struct btrfs_bio *orig_bbio;
68 struct work_struct write_end_work;
69 };
70
71 /* Must be last. */
72 struct btrfs_bio bbio;
73};
74
75static inline unsigned int btrfs_compress_type(unsigned int type_level)
76{
77 return (type_level & 0xF);
78}
79
80static inline unsigned int btrfs_compress_level(unsigned int type_level)
81{
82 return ((type_level & 0xF0) >> 4);
83}
84
85int __init btrfs_init_compress(void);
86void __cold btrfs_exit_compress(void);
87
88int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping,
89 u64 start, struct page **pages,
90 unsigned long *out_pages,
91 unsigned long *total_in,
92 unsigned long *total_out);
93int btrfs_decompress(int type, const u8 *data_in, struct page *dest_page,
94 unsigned long start_byte, size_t srclen, size_t destlen);
95int btrfs_decompress_buf2page(const char *buf, u32 buf_len,
96 struct compressed_bio *cb, u32 decompressed);
97
98void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered,
99 struct page **compressed_pages,
100 unsigned int nr_pages,
101 blk_opf_t write_flags,
102 bool writeback);
103void btrfs_submit_compressed_read(struct btrfs_bio *bbio);
104
105unsigned int btrfs_compress_str2level(unsigned int type, const char *str);
106
107struct page *btrfs_alloc_compr_page(void);
108void btrfs_free_compr_page(struct page *page);
109
110enum btrfs_compression_type {
111 BTRFS_COMPRESS_NONE = 0,
112 BTRFS_COMPRESS_ZLIB = 1,
113 BTRFS_COMPRESS_LZO = 2,
114 BTRFS_COMPRESS_ZSTD = 3,
115 BTRFS_NR_COMPRESS_TYPES = 4,
116};
117
118struct workspace_manager {
119 struct list_head idle_ws;
120 spinlock_t ws_lock;
121 /* Number of free workspaces */
122 int free_ws;
123 /* Total number of allocated workspaces */
124 atomic_t total_ws;
125 /* Waiters for a free workspace */
126 wait_queue_head_t ws_wait;
127};
128
129struct list_head *btrfs_get_workspace(int type, unsigned int level);
130void btrfs_put_workspace(int type, struct list_head *ws);
131
132struct btrfs_compress_op {
133 struct workspace_manager *workspace_manager;
134 /* Maximum level supported by the compression algorithm */
135 unsigned int max_level;
136 unsigned int default_level;
137};
138
139/* The heuristic workspaces are managed via the 0th workspace manager */
140#define BTRFS_NR_WORKSPACE_MANAGERS BTRFS_NR_COMPRESS_TYPES
141
142extern const struct btrfs_compress_op btrfs_heuristic_compress;
143extern const struct btrfs_compress_op btrfs_zlib_compress;
144extern const struct btrfs_compress_op btrfs_lzo_compress;
145extern const struct btrfs_compress_op btrfs_zstd_compress;
146
147const char* btrfs_compress_type2str(enum btrfs_compression_type type);
148bool btrfs_compress_is_valid_type(const char *str, size_t len);
149
150int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end);
151
152int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
153 u64 start, struct page **pages, unsigned long *out_pages,
154 unsigned long *total_in, unsigned long *total_out);
155int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
156int zlib_decompress(struct list_head *ws, const u8 *data_in,
157 struct page *dest_page, unsigned long dest_pgoff, size_t srclen,
158 size_t destlen);
159struct list_head *zlib_alloc_workspace(unsigned int level);
160void zlib_free_workspace(struct list_head *ws);
161struct list_head *zlib_get_workspace(unsigned int level);
162
163int lzo_compress_pages(struct list_head *ws, struct address_space *mapping,
164 u64 start, struct page **pages, unsigned long *out_pages,
165 unsigned long *total_in, unsigned long *total_out);
166int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
167int lzo_decompress(struct list_head *ws, const u8 *data_in,
168 struct page *dest_page, unsigned long dest_pgoff, size_t srclen,
169 size_t destlen);
170struct list_head *lzo_alloc_workspace(unsigned int level);
171void lzo_free_workspace(struct list_head *ws);
172
173int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
174 u64 start, struct page **pages, unsigned long *out_pages,
175 unsigned long *total_in, unsigned long *total_out);
176int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
177int zstd_decompress(struct list_head *ws, const u8 *data_in,
178 struct page *dest_page, unsigned long dest_pgoff, size_t srclen,
179 size_t destlen);
180void zstd_init_workspace_manager(void);
181void zstd_cleanup_workspace_manager(void);
182struct list_head *zstd_alloc_workspace(unsigned int level);
183void zstd_free_workspace(struct list_head *ws);
184struct list_head *zstd_get_workspace(unsigned int level);
185void zstd_put_workspace(struct list_head *ws);
186
187#endif