diff options
Diffstat (limited to 'fs/btrfs/compression.h')
| -rw-r--r-- | fs/btrfs/compression.h | 248 |
1 files changed, 176 insertions, 72 deletions
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h index 0c803b4fbf93..e0228017e861 100644 --- a/fs/btrfs/compression.h +++ b/fs/btrfs/compression.h @@ -1,81 +1,185 @@ +/* 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> +#include <linux/mm.h> +#include <linux/list.h> +#include <linux/workqueue.h> +#include <linux/wait.h> +#include <linux/pagemap.h> +#include "bio.h" +#include "fs.h" +#include "btrfs_inode.h" + +struct address_space; +struct inode; +struct btrfs_inode; +struct btrfs_ordered_extent; + +/* + * 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. * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public - * License v2 as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 021110-1307, USA. + * 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. */ -#ifndef __BTRFS_COMPRESSION_ -#define __BTRFS_COMPRESSION_ - -void btrfs_init_compress(void); -void btrfs_exit_compress(void); - -int btrfs_compress_pages(int type, struct address_space *mapping, - u64 start, unsigned long len, - struct page **pages, - unsigned long nr_dest_pages, - unsigned long *out_pages, - unsigned long *total_in, - unsigned long *total_out, - unsigned long max_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(char *buf, unsigned long buf_start, - unsigned long total_out, u64 disk_start, - struct bio_vec *bvec, int vcnt, - unsigned long *pg_index, - unsigned long *pg_offset); - -int btrfs_submit_compressed_write(struct inode *inode, u64 start, - unsigned long len, u64 disk_start, - unsigned long compressed_len, - struct page **compressed_pages, - unsigned long nr_pages); -int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, - int mirror_num, unsigned long bio_flags); - -struct btrfs_compress_op { - struct list_head *(*alloc_workspace)(void); - - void (*free_workspace)(struct list_head *workspace); - - int (*compress_pages)(struct list_head *workspace, - struct address_space *mapping, - u64 start, unsigned long len, - struct page **pages, - unsigned long nr_dest_pages, - unsigned long *out_pages, - unsigned long *total_in, - unsigned long *total_out, - unsigned long max_out); - - int (*decompress_biovec)(struct list_head *workspace, - struct page **pages_in, - u64 disk_start, - struct bio_vec *bvec, - int vcnt, - size_t srclen); - - int (*decompress)(struct list_head *workspace, - unsigned char *data_in, - struct page *dest_page, - unsigned long start_byte, - size_t srclen, size_t destlen); +/* Maximum length of compressed data stored on disk */ +#define BTRFS_MAX_COMPRESSED (SZ_128K) +#define BTRFS_MAX_COMPRESSED_PAGES (BTRFS_MAX_COMPRESSED / PAGE_SIZE) +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 compressed folios in the array. */ + unsigned int nr_folios; + + /* The folios with the compressed data on them. */ + struct folio **compressed_folios; + + /* 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; + + /* For reads, this is the bio we are copying the data into. */ + struct btrfs_bio *orig_bbio; + + /* Must be last. */ + struct btrfs_bio bbio; }; -extern struct btrfs_compress_op btrfs_zlib_compress; -extern struct btrfs_compress_op btrfs_lzo_compress; +static inline struct btrfs_fs_info *cb_to_fs_info(const struct compressed_bio *cb) +{ + return cb->bbio.inode->root->fs_info; +} + +/* @range_end must be exclusive. */ +static inline u32 btrfs_calc_input_length(struct folio *folio, u64 range_end, u64 cur) +{ + /* @cur must be inside the folio. */ + ASSERT(folio_pos(folio) <= cur); + ASSERT(cur < folio_next_pos(folio)); + return umin(range_end, folio_next_pos(folio)) - cur; +} + +int btrfs_alloc_compress_wsm(struct btrfs_fs_info *fs_info); +void btrfs_free_compress_wsm(struct btrfs_fs_info *fs_info); + +int __init btrfs_init_compress(void); +void __cold btrfs_exit_compress(void); + +bool btrfs_compress_level_valid(unsigned int type, int level); +int btrfs_compress_folios(unsigned int type, int level, struct btrfs_inode *inode, + u64 start, struct folio **folios, unsigned long *out_folios, + unsigned long *total_in, unsigned long *total_out); +int btrfs_decompress(int type, const u8 *data_in, struct folio *dest_folio, + unsigned long dest_pgoff, size_t srclen, size_t destlen); +int btrfs_decompress_buf2page(const char *buf, u32 buf_len, + struct compressed_bio *cb, u32 decompressed); + +void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered, + struct folio **compressed_folios, + unsigned int nr_folios, blk_opf_t write_flags, + bool writeback); +void btrfs_submit_compressed_read(struct btrfs_bio *bbio); + +int btrfs_compress_str2level(unsigned int type, const char *str, int *level_ret); + +struct folio *btrfs_alloc_compr_folio(struct btrfs_fs_info *fs_info); +void btrfs_free_compr_folio(struct folio *folio); + +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(struct btrfs_fs_info *fs_info, int type, int level); +void btrfs_put_workspace(struct btrfs_fs_info *fs_info, int type, struct list_head *ws); + +struct btrfs_compress_levels { + /* Maximum level supported by the compression algorithm */ + int min_level; + int max_level; + 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_levels btrfs_heuristic_compress; +extern const struct btrfs_compress_levels btrfs_zlib_compress; +extern const struct btrfs_compress_levels btrfs_lzo_compress; +extern const struct btrfs_compress_levels 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 btrfs_inode *inode, u64 start, u64 end); + +int btrfs_compress_filemap_get_folio(struct address_space *mapping, u64 start, + struct folio **in_folio_ret); + +int zlib_compress_folios(struct list_head *ws, struct btrfs_inode *inode, + u64 start, struct folio **folios, unsigned long *out_folios, + 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, const u8 *data_in, + struct folio *dest_folio, unsigned long dest_pgoff, size_t srclen, + size_t destlen); +struct list_head *zlib_alloc_workspace(struct btrfs_fs_info *fs_info, unsigned int level); +void zlib_free_workspace(struct list_head *ws); +struct list_head *zlib_get_workspace(struct btrfs_fs_info *fs_info, unsigned int level); + +int lzo_compress_folios(struct list_head *ws, struct btrfs_inode *inode, + u64 start, struct folio **folios, unsigned long *out_folios, + 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, const u8 *data_in, + struct folio *dest_folio, unsigned long dest_pgoff, size_t srclen, + size_t destlen); +struct list_head *lzo_alloc_workspace(struct btrfs_fs_info *fs_info); +void lzo_free_workspace(struct list_head *ws); + +int zstd_compress_folios(struct list_head *ws, struct btrfs_inode *inode, + u64 start, struct folio **folios, unsigned long *out_folios, + 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, const u8 *data_in, + struct folio *dest_folio, unsigned long dest_pgoff, size_t srclen, + size_t destlen); +int zstd_alloc_workspace_manager(struct btrfs_fs_info *fs_info); +void zstd_free_workspace_manager(struct btrfs_fs_info *fs_info); +struct list_head *zstd_alloc_workspace(struct btrfs_fs_info *fs_info, int level); +void zstd_free_workspace(struct list_head *ws); +struct list_head *zstd_get_workspace(struct btrfs_fs_info *fs_info, int level); +void zstd_put_workspace(struct btrfs_fs_info *fs_info, struct list_head *ws); #endif |