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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 folios in the array. */
45 unsigned int nr_folios;
46
47 /* The folios with the compressed data on them. */
48 struct folio **compressed_folios;
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
85/* @range_end must be exclusive. */
86static inline u32 btrfs_calc_input_length(u64 range_end, u64 cur)
87{
88 u64 page_end = round_down(cur, PAGE_SIZE) + PAGE_SIZE;
89
90 return min(range_end, page_end) - cur;
91}
92
93int __init btrfs_init_compress(void);
94void __cold btrfs_exit_compress(void);
95
96int btrfs_compress_folios(unsigned int type_level, struct address_space *mapping,
97 u64 start, struct folio **folios, unsigned long *out_folios,
98 unsigned long *total_in, unsigned long *total_out);
99int btrfs_decompress(int type, const u8 *data_in, struct folio *dest_folio,
100 unsigned long start_byte, size_t srclen, size_t destlen);
101int btrfs_decompress_buf2page(const char *buf, u32 buf_len,
102 struct compressed_bio *cb, u32 decompressed);
103
104void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered,
105 struct folio **compressed_folios,
106 unsigned int nr_folios, blk_opf_t write_flags,
107 bool writeback);
108void btrfs_submit_compressed_read(struct btrfs_bio *bbio);
109
110unsigned int btrfs_compress_str2level(unsigned int type, const char *str);
111
112struct folio *btrfs_alloc_compr_folio(void);
113void btrfs_free_compr_folio(struct folio *folio);
114
115enum btrfs_compression_type {
116 BTRFS_COMPRESS_NONE = 0,
117 BTRFS_COMPRESS_ZLIB = 1,
118 BTRFS_COMPRESS_LZO = 2,
119 BTRFS_COMPRESS_ZSTD = 3,
120 BTRFS_NR_COMPRESS_TYPES = 4,
121};
122
123struct workspace_manager {
124 struct list_head idle_ws;
125 spinlock_t ws_lock;
126 /* Number of free workspaces */
127 int free_ws;
128 /* Total number of allocated workspaces */
129 atomic_t total_ws;
130 /* Waiters for a free workspace */
131 wait_queue_head_t ws_wait;
132};
133
134struct list_head *btrfs_get_workspace(int type, unsigned int level);
135void btrfs_put_workspace(int type, struct list_head *ws);
136
137struct btrfs_compress_op {
138 struct workspace_manager *workspace_manager;
139 /* Maximum level supported by the compression algorithm */
140 unsigned int max_level;
141 unsigned int default_level;
142};
143
144/* The heuristic workspaces are managed via the 0th workspace manager */
145#define BTRFS_NR_WORKSPACE_MANAGERS BTRFS_NR_COMPRESS_TYPES
146
147extern const struct btrfs_compress_op btrfs_heuristic_compress;
148extern const struct btrfs_compress_op btrfs_zlib_compress;
149extern const struct btrfs_compress_op btrfs_lzo_compress;
150extern const struct btrfs_compress_op btrfs_zstd_compress;
151
152const char* btrfs_compress_type2str(enum btrfs_compression_type type);
153bool btrfs_compress_is_valid_type(const char *str, size_t len);
154
155int btrfs_compress_heuristic(struct btrfs_inode *inode, u64 start, u64 end);
156
157int btrfs_compress_filemap_get_folio(struct address_space *mapping, u64 start,
158 struct folio **in_folio_ret);
159
160int zlib_compress_folios(struct list_head *ws, struct address_space *mapping,
161 u64 start, struct folio **folios, unsigned long *out_folios,
162 unsigned long *total_in, unsigned long *total_out);
163int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
164int zlib_decompress(struct list_head *ws, const u8 *data_in,
165 struct folio *dest_folio, unsigned long dest_pgoff, size_t srclen,
166 size_t destlen);
167struct list_head *zlib_alloc_workspace(unsigned int level);
168void zlib_free_workspace(struct list_head *ws);
169struct list_head *zlib_get_workspace(unsigned int level);
170
171int lzo_compress_folios(struct list_head *ws, struct address_space *mapping,
172 u64 start, struct folio **folios, unsigned long *out_folios,
173 unsigned long *total_in, unsigned long *total_out);
174int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
175int lzo_decompress(struct list_head *ws, const u8 *data_in,
176 struct folio *dest_folio, unsigned long dest_pgoff, size_t srclen,
177 size_t destlen);
178struct list_head *lzo_alloc_workspace(void);
179void lzo_free_workspace(struct list_head *ws);
180
181int zstd_compress_folios(struct list_head *ws, struct address_space *mapping,
182 u64 start, struct folio **folios, unsigned long *out_folios,
183 unsigned long *total_in, unsigned long *total_out);
184int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
185int zstd_decompress(struct list_head *ws, const u8 *data_in,
186 struct folio *dest_folio, unsigned long dest_pgoff, size_t srclen,
187 size_t destlen);
188void zstd_init_workspace_manager(void);
189void zstd_cleanup_workspace_manager(void);
190struct list_head *zstd_alloc_workspace(unsigned int level);
191void zstd_free_workspace(struct list_head *ws);
192struct list_head *zstd_get_workspace(unsigned int level);
193void zstd_put_workspace(struct list_head *ws);
194
195#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
11/*
12 * We want to make sure that amount of RAM required to uncompress an extent is
13 * reasonable, so we limit the total size in ram of a compressed extent to
14 * 128k. This is a crucial number because it also controls how easily we can
15 * spread reads across cpus for decompression.
16 *
17 * We also want to make sure the amount of IO required to do a random read is
18 * reasonably small, so we limit the size of a compressed extent to 128k.
19 */
20
21/* Maximum length of compressed data stored on disk */
22#define BTRFS_MAX_COMPRESSED (SZ_128K)
23/* Maximum size of data before compression */
24#define BTRFS_MAX_UNCOMPRESSED (SZ_128K)
25
26#define BTRFS_ZLIB_DEFAULT_LEVEL 3
27
28struct compressed_bio {
29 /* number of bios pending for this compressed extent */
30 refcount_t pending_bios;
31
32 /* the pages with the compressed data on them */
33 struct page **compressed_pages;
34
35 /* inode that owns this data */
36 struct inode *inode;
37
38 /* starting offset in the inode for our pages */
39 u64 start;
40
41 /* number of bytes in the inode we're working on */
42 unsigned long len;
43
44 /* number of bytes on disk */
45 unsigned long compressed_len;
46
47 /* the compression algorithm for this bio */
48 int compress_type;
49
50 /* number of compressed pages in the array */
51 unsigned long nr_pages;
52
53 /* IO errors */
54 int errors;
55 int mirror_num;
56
57 /* for reads, this is the bio we are copying the data into */
58 struct bio *orig_bio;
59
60 /*
61 * the start of a variable length array of checksums only
62 * used by reads
63 */
64 u8 sums[];
65};
66
67static inline unsigned int btrfs_compress_type(unsigned int type_level)
68{
69 return (type_level & 0xF);
70}
71
72static inline unsigned int btrfs_compress_level(unsigned int type_level)
73{
74 return ((type_level & 0xF0) >> 4);
75}
76
77void __init btrfs_init_compress(void);
78void __cold btrfs_exit_compress(void);
79
80int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping,
81 u64 start, struct page **pages,
82 unsigned long *out_pages,
83 unsigned long *total_in,
84 unsigned long *total_out);
85int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
86 unsigned long start_byte, size_t srclen, size_t destlen);
87int btrfs_decompress_buf2page(const char *buf, unsigned long buf_start,
88 unsigned long total_out, u64 disk_start,
89 struct bio *bio);
90
91blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start,
92 unsigned long len, u64 disk_start,
93 unsigned long compressed_len,
94 struct page **compressed_pages,
95 unsigned long nr_pages,
96 unsigned int write_flags);
97blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
98 int mirror_num, unsigned long bio_flags);
99
100unsigned int btrfs_compress_str2level(unsigned int type, const char *str);
101
102enum btrfs_compression_type {
103 BTRFS_COMPRESS_NONE = 0,
104 BTRFS_COMPRESS_ZLIB = 1,
105 BTRFS_COMPRESS_LZO = 2,
106 BTRFS_COMPRESS_ZSTD = 3,
107 BTRFS_COMPRESS_TYPES = 3,
108};
109
110struct workspace_manager {
111 const struct btrfs_compress_op *ops;
112 struct list_head idle_ws;
113 spinlock_t ws_lock;
114 /* Number of free workspaces */
115 int free_ws;
116 /* Total number of allocated workspaces */
117 atomic_t total_ws;
118 /* Waiters for a free workspace */
119 wait_queue_head_t ws_wait;
120};
121
122void btrfs_init_workspace_manager(struct workspace_manager *wsm,
123 const struct btrfs_compress_op *ops);
124struct list_head *btrfs_get_workspace(struct workspace_manager *wsm,
125 unsigned int level);
126void btrfs_put_workspace(struct workspace_manager *wsm, struct list_head *ws);
127void btrfs_cleanup_workspace_manager(struct workspace_manager *wsm);
128
129struct btrfs_compress_op {
130 void (*init_workspace_manager)(void);
131
132 void (*cleanup_workspace_manager)(void);
133
134 struct list_head *(*get_workspace)(unsigned int level);
135
136 void (*put_workspace)(struct list_head *ws);
137
138 struct list_head *(*alloc_workspace)(unsigned int level);
139
140 void (*free_workspace)(struct list_head *workspace);
141
142 int (*compress_pages)(struct list_head *workspace,
143 struct address_space *mapping,
144 u64 start,
145 struct page **pages,
146 unsigned long *out_pages,
147 unsigned long *total_in,
148 unsigned long *total_out);
149
150 int (*decompress_bio)(struct list_head *workspace,
151 struct compressed_bio *cb);
152
153 int (*decompress)(struct list_head *workspace,
154 unsigned char *data_in,
155 struct page *dest_page,
156 unsigned long start_byte,
157 size_t srclen, size_t destlen);
158
159 /* Maximum level supported by the compression algorithm */
160 unsigned int max_level;
161 unsigned int default_level;
162};
163
164/* The heuristic workspaces are managed via the 0th workspace manager */
165#define BTRFS_NR_WORKSPACE_MANAGERS (BTRFS_COMPRESS_TYPES + 1)
166
167extern const struct btrfs_compress_op btrfs_heuristic_compress;
168extern const struct btrfs_compress_op btrfs_zlib_compress;
169extern const struct btrfs_compress_op btrfs_lzo_compress;
170extern const struct btrfs_compress_op btrfs_zstd_compress;
171
172const char* btrfs_compress_type2str(enum btrfs_compression_type type);
173bool btrfs_compress_is_valid_type(const char *str, size_t len);
174
175unsigned int btrfs_compress_set_level(int type, unsigned level);
176
177int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end);
178
179#endif