5e9c466d6e
Squashfs does not implement .readpages(), so the kernel just repeatedly calls .readpage(). The readpages function tries to pack as much pages as possible in the same page actor so that only 1 read request is issued. Now that the read requests are asynchronous, the kernel can truly prefetch pages using its readahead algorithm. Signed-off-by: Adrien Schildknecht <adriens@google.com> Change-Id: Ice70e029dc24526f61e4e5a1a902588be2212498
120 lines
4.3 KiB
C
120 lines
4.3 KiB
C
/*
|
|
* Squashfs - a compressed read only filesystem for Linux
|
|
*
|
|
* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
|
|
* Phillip Lougher <phillip@squashfs.org.uk>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2,
|
|
* or (at your option) any later version.
|
|
*
|
|
* 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*
|
|
* squashfs.h
|
|
*/
|
|
|
|
#define TRACE(s, args...) pr_debug("SQUASHFS: "s, ## args)
|
|
|
|
#define ERROR(s, args...) pr_err("SQUASHFS error: "s, ## args)
|
|
|
|
#define WARNING(s, args...) pr_warn("SQUASHFS: "s, ## args)
|
|
|
|
/* block.c */
|
|
extern int squashfs_init_read_wq(void);
|
|
extern void squashfs_destroy_read_wq(void);
|
|
extern int squashfs_read_data(struct super_block *, u64, int, u64 *,
|
|
struct squashfs_page_actor *);
|
|
extern int squashfs_read_data(struct super_block *, u64, int, u64 *,
|
|
struct squashfs_page_actor *);
|
|
extern int squashfs_read_data_async(struct super_block *, u64, int, u64 *,
|
|
struct squashfs_page_actor *);
|
|
|
|
/* cache.c */
|
|
extern struct squashfs_cache *squashfs_cache_init(char *, int, int);
|
|
extern void squashfs_cache_delete(struct squashfs_cache *);
|
|
extern struct squashfs_cache_entry *squashfs_cache_get(struct super_block *,
|
|
struct squashfs_cache *, u64, int);
|
|
extern void squashfs_cache_put(struct squashfs_cache_entry *);
|
|
extern int squashfs_copy_data(void *, struct squashfs_cache_entry *, int, int);
|
|
extern int squashfs_read_metadata(struct super_block *, void *, u64 *,
|
|
int *, int);
|
|
extern struct squashfs_cache_entry *squashfs_get_fragment(struct super_block *,
|
|
u64, int);
|
|
extern struct squashfs_cache_entry *squashfs_get_datablock(struct super_block *,
|
|
u64, int);
|
|
extern void *squashfs_read_table(struct super_block *, u64, int);
|
|
|
|
/* decompressor.c */
|
|
extern const struct squashfs_decompressor *squashfs_lookup_decompressor(int);
|
|
extern void *squashfs_decompressor_setup(struct super_block *, unsigned short);
|
|
|
|
/* decompressor_xxx.c */
|
|
extern void *squashfs_decompressor_create(struct squashfs_sb_info *, void *);
|
|
extern void squashfs_decompressor_destroy(struct squashfs_sb_info *);
|
|
extern int squashfs_decompress(struct squashfs_sb_info *, struct buffer_head **,
|
|
int, int, int, struct squashfs_page_actor *);
|
|
extern int squashfs_max_decompressors(void);
|
|
|
|
/* export.c */
|
|
extern __le64 *squashfs_read_inode_lookup_table(struct super_block *, u64, u64,
|
|
unsigned int);
|
|
|
|
/* fragment.c */
|
|
extern int squashfs_frag_lookup(struct super_block *, unsigned int, u64 *);
|
|
extern __le64 *squashfs_read_fragment_index_table(struct super_block *,
|
|
u64, u64, unsigned int);
|
|
|
|
/* file.c */
|
|
void squashfs_copy_cache(struct page *, struct squashfs_cache_entry *, int,
|
|
int);
|
|
|
|
/* file_direct.c */
|
|
extern int squashfs_readpages_block(struct page *, struct list_head *,
|
|
unsigned int *, struct address_space *, int, u64, int);
|
|
|
|
/* id.c */
|
|
extern int squashfs_get_id(struct super_block *, unsigned int, unsigned int *);
|
|
extern __le64 *squashfs_read_id_index_table(struct super_block *, u64, u64,
|
|
unsigned short);
|
|
|
|
/* inode.c */
|
|
extern struct inode *squashfs_iget(struct super_block *, long long,
|
|
unsigned int);
|
|
extern int squashfs_read_inode(struct inode *, long long);
|
|
|
|
/* xattr.c */
|
|
extern ssize_t squashfs_listxattr(struct dentry *, char *, size_t);
|
|
|
|
/*
|
|
* Inodes, files, decompressor and xattr operations
|
|
*/
|
|
|
|
/* dir.c */
|
|
extern const struct file_operations squashfs_dir_ops;
|
|
|
|
/* export.c */
|
|
extern const struct export_operations squashfs_export_ops;
|
|
|
|
/* file.c */
|
|
extern const struct address_space_operations squashfs_aops;
|
|
|
|
/* inode.c */
|
|
extern const struct inode_operations squashfs_inode_ops;
|
|
|
|
/* namei.c */
|
|
extern const struct inode_operations squashfs_dir_inode_ops;
|
|
|
|
/* symlink.c */
|
|
extern const struct address_space_operations squashfs_symlink_aops;
|
|
extern const struct inode_operations squashfs_symlink_inode_ops;
|
|
|
|
/* xattr.c */
|
|
extern const struct xattr_handler *squashfs_xattr_handlers[];
|