188 строки
6.1 KiB
C
188 строки
6.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Copyright (C) 2008 Oracle. All rights reserved.
|
|
*/
|
|
|
|
#ifndef BTRFS_COMPRESSION_H
|
|
#define BTRFS_COMPRESSION_H
|
|
|
|
#include <linux/sizes.h>
|
|
|
|
struct btrfs_inode;
|
|
|
|
/*
|
|
* We want to make sure that amount of RAM required to uncompress an extent is
|
|
* reasonable, so we limit the total size in ram of a compressed extent to
|
|
* 128k. This is a crucial number because it also controls how easily we can
|
|
* spread reads across cpus for decompression.
|
|
*
|
|
* We also want to make sure the amount of IO required to do a random read is
|
|
* reasonably small, so we limit the size of a compressed extent to 128k.
|
|
*/
|
|
|
|
/* Maximum length of compressed data stored on disk */
|
|
#define BTRFS_MAX_COMPRESSED (SZ_128K)
|
|
static_assert((BTRFS_MAX_COMPRESSED % PAGE_SIZE) == 0);
|
|
|
|
/* Maximum size of data before compression */
|
|
#define BTRFS_MAX_UNCOMPRESSED (SZ_128K)
|
|
|
|
#define BTRFS_ZLIB_DEFAULT_LEVEL 3
|
|
|
|
struct compressed_bio {
|
|
/* Number of sectors with unfinished IO (unsubmitted or unfinished) */
|
|
refcount_t pending_sectors;
|
|
|
|
/* Number of compressed pages in the array */
|
|
unsigned int nr_pages;
|
|
|
|
/* the pages with the compressed data on them */
|
|
struct page **compressed_pages;
|
|
|
|
/* inode that owns this data */
|
|
struct inode *inode;
|
|
|
|
/* starting offset in the inode for our pages */
|
|
u64 start;
|
|
|
|
/* Number of bytes in the inode we're working on */
|
|
unsigned int len;
|
|
|
|
/* Number of bytes on disk */
|
|
unsigned int compressed_len;
|
|
|
|
/* The compression algorithm for this bio */
|
|
u8 compress_type;
|
|
|
|
/* Whether this is a write for writeback. */
|
|
bool writeback;
|
|
|
|
/* IO errors */
|
|
blk_status_t status;
|
|
int mirror_num;
|
|
|
|
/* for reads, this is the bio we are copying the data into */
|
|
struct bio *orig_bio;
|
|
|
|
/*
|
|
* the start of a variable length array of checksums only
|
|
* used by reads
|
|
*/
|
|
u8 sums[];
|
|
};
|
|
|
|
static inline unsigned int btrfs_compress_type(unsigned int type_level)
|
|
{
|
|
return (type_level & 0xF);
|
|
}
|
|
|
|
static inline unsigned int btrfs_compress_level(unsigned int type_level)
|
|
{
|
|
return ((type_level & 0xF0) >> 4);
|
|
}
|
|
|
|
void __init btrfs_init_compress(void);
|
|
void __cold btrfs_exit_compress(void);
|
|
|
|
int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping,
|
|
u64 start, struct page **pages,
|
|
unsigned long *out_pages,
|
|
unsigned long *total_in,
|
|
unsigned long *total_out);
|
|
int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
|
|
unsigned long start_byte, size_t srclen, size_t destlen);
|
|
int btrfs_decompress_buf2page(const char *buf, u32 buf_len,
|
|
struct compressed_bio *cb, u32 decompressed);
|
|
|
|
blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start,
|
|
unsigned int len, u64 disk_start,
|
|
unsigned int compressed_len,
|
|
struct page **compressed_pages,
|
|
unsigned int nr_pages,
|
|
unsigned int write_flags,
|
|
struct cgroup_subsys_state *blkcg_css,
|
|
bool writeback);
|
|
blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
|
|
int mirror_num, unsigned long bio_flags);
|
|
|
|
unsigned int btrfs_compress_str2level(unsigned int type, const char *str);
|
|
|
|
enum btrfs_compression_type {
|
|
BTRFS_COMPRESS_NONE = 0,
|
|
BTRFS_COMPRESS_ZLIB = 1,
|
|
BTRFS_COMPRESS_LZO = 2,
|
|
BTRFS_COMPRESS_ZSTD = 3,
|
|
BTRFS_NR_COMPRESS_TYPES = 4,
|
|
};
|
|
|
|
struct workspace_manager {
|
|
struct list_head idle_ws;
|
|
spinlock_t ws_lock;
|
|
/* Number of free workspaces */
|
|
int free_ws;
|
|
/* Total number of allocated workspaces */
|
|
atomic_t total_ws;
|
|
/* Waiters for a free workspace */
|
|
wait_queue_head_t ws_wait;
|
|
};
|
|
|
|
struct list_head *btrfs_get_workspace(int type, unsigned int level);
|
|
void btrfs_put_workspace(int type, struct list_head *ws);
|
|
|
|
struct btrfs_compress_op {
|
|
struct workspace_manager *workspace_manager;
|
|
/* Maximum level supported by the compression algorithm */
|
|
unsigned int max_level;
|
|
unsigned int default_level;
|
|
};
|
|
|
|
/* The heuristic workspaces are managed via the 0th workspace manager */
|
|
#define BTRFS_NR_WORKSPACE_MANAGERS BTRFS_NR_COMPRESS_TYPES
|
|
|
|
extern const struct btrfs_compress_op btrfs_heuristic_compress;
|
|
extern const struct btrfs_compress_op btrfs_zlib_compress;
|
|
extern const struct btrfs_compress_op btrfs_lzo_compress;
|
|
extern const struct btrfs_compress_op btrfs_zstd_compress;
|
|
|
|
const char* btrfs_compress_type2str(enum btrfs_compression_type type);
|
|
bool btrfs_compress_is_valid_type(const char *str, size_t len);
|
|
|
|
int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end);
|
|
|
|
int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
|
|
u64 start, struct page **pages, unsigned long *out_pages,
|
|
unsigned long *total_in, unsigned long *total_out);
|
|
int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
|
|
int zlib_decompress(struct list_head *ws, unsigned char *data_in,
|
|
struct page *dest_page, unsigned long start_byte, size_t srclen,
|
|
size_t destlen);
|
|
struct list_head *zlib_alloc_workspace(unsigned int level);
|
|
void zlib_free_workspace(struct list_head *ws);
|
|
struct list_head *zlib_get_workspace(unsigned int level);
|
|
|
|
int lzo_compress_pages(struct list_head *ws, struct address_space *mapping,
|
|
u64 start, struct page **pages, unsigned long *out_pages,
|
|
unsigned long *total_in, unsigned long *total_out);
|
|
int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
|
|
int lzo_decompress(struct list_head *ws, unsigned char *data_in,
|
|
struct page *dest_page, unsigned long start_byte, size_t srclen,
|
|
size_t destlen);
|
|
struct list_head *lzo_alloc_workspace(unsigned int level);
|
|
void lzo_free_workspace(struct list_head *ws);
|
|
|
|
int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
|
|
u64 start, struct page **pages, unsigned long *out_pages,
|
|
unsigned long *total_in, unsigned long *total_out);
|
|
int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
|
|
int zstd_decompress(struct list_head *ws, unsigned char *data_in,
|
|
struct page *dest_page, unsigned long start_byte, size_t srclen,
|
|
size_t destlen);
|
|
void zstd_init_workspace_manager(void);
|
|
void zstd_cleanup_workspace_manager(void);
|
|
struct list_head *zstd_alloc_workspace(unsigned int level);
|
|
void zstd_free_workspace(struct list_head *ws);
|
|
struct list_head *zstd_get_workspace(unsigned int level);
|
|
void zstd_put_workspace(struct list_head *ws);
|
|
|
|
#endif
|