diff options
| -rw-r--r-- | fs/squashfs/Makefile | 2 | ||||
| -rw-r--r-- | fs/squashfs/block.c | 3 | ||||
| -rw-r--r-- | fs/squashfs/decompressor.c | 58 | ||||
| -rw-r--r-- | fs/squashfs/decompressor.h | 55 | ||||
| -rw-r--r-- | fs/squashfs/squashfs.h | 14 | ||||
| -rw-r--r-- | fs/squashfs/squashfs_fs_sb.h | 41 | ||||
| -rw-r--r-- | fs/squashfs/super.c | 45 | ||||
| -rw-r--r-- | fs/squashfs/zlib_wrapper.c | 17 |
8 files changed, 184 insertions, 51 deletions
diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile index a397e6f..df8a19e 100644 --- a/fs/squashfs/Makefile +++ b/fs/squashfs/Makefile @@ -4,4 +4,4 @@ obj-$(CONFIG_SQUASHFS) += squashfs.o squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o -squashfs-y += namei.o super.o symlink.o zlib_wrapper.o +squashfs-y += namei.o super.o symlink.o zlib_wrapper.o decompressor.o diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c index 3f836e1..1cb0d81 100644 --- a/fs/squashfs/block.c +++ b/fs/squashfs/block.c @@ -36,6 +36,7 @@ #include "squashfs_fs_sb.h" #include "squashfs_fs_i.h" #include "squashfs.h" +#include "decompressor.h" /* * Read the metadata block length, this is stored in the first two @@ -151,7 +152,7 @@ int squashfs_read_data(struct super_block *sb, void **buffer, u64 index, } if (compressed) { - length = squashfs_zlib_uncompress(msblk, buffer, bh, b, offset, + length = squashfs_decompress(msblk, buffer, bh, b, offset, length, srclength, pages); if (length < 0) goto read_failure; diff --git a/fs/squashfs/decompressor.c b/fs/squashfs/decompressor.c new file mode 100644 index 0000000..0072ccd --- /dev/null +++ b/fs/squashfs/decompressor.c @@ -0,0 +1,58 @@ +/* + * Squashfs - a compressed read only filesystem for Linux + * + * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 + * Phillip Lougher <phillip@lougher.demon.co.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. + * + * decompressor.c + */ + +#include <linux/types.h> +#include <linux/mutex.h> +#include <linux/buffer_head.h> + +#include "squashfs_fs.h" +#include "squashfs_fs_sb.h" +#include "squashfs_fs_i.h" +#include "decompressor.h" +#include "squashfs.h" + +/* + * This file (and decompressor.h) implements a decompressor framework for + * Squashfs, allowing multiple decompressors to be easily supported + */ + +static const struct squashfs_decompressor squashfs_unknown_comp_ops = { + NULL, NULL, NULL, 0, "unknown", 0 +}; + +static const struct squashfs_decompressor *decompressor[] = { + &squashfs_zlib_comp_ops, + &squashfs_unknown_comp_ops +}; + + +const struct squashfs_decompressor *squashfs_lookup_decompressor(int id) +{ + int i; + + for (i = 0; decompressor[i]->id; i++) + if (id == decompressor[i]->id) + break; + + return decompressor[i]; +} diff --git a/fs/squashfs/decompressor.h b/fs/squashfs/decompressor.h new file mode 100644 index 0000000..7425f80 --- /dev/null +++ b/fs/squashfs/decompressor.h @@ -0,0 +1,55 @@ +#ifndef DECOMPRESSOR_H +#define DECOMPRESSOR_H +/* + * Squashfs - a compressed read only filesystem for Linux + * + * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 + * Phillip Lougher <phillip@lougher.demon.co.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. + * + * decompressor.h + */ + +struct squashfs_decompressor { + void *(*init)(struct squashfs_sb_info *); + void (*free)(void *); + int (*decompress)(struct squashfs_sb_info *, void **, + struct buffer_head **, int, int, int, int, int); + int id; + char *name; + int supported; +}; + +static inline void *squashfs_decompressor_init(struct squashfs_sb_info *msblk) +{ + return msblk->decompressor->init(msblk); +} + +static inline void squashfs_decompressor_free(struct squashfs_sb_info *msblk, + void *s) +{ + if (msblk->decompressor) + msblk->decompressor->free(s); +} + +static inline int squashfs_decompress(struct squashfs_sb_info *msblk, + void **buffer, struct buffer_head **bh, int b, int offset, int length, + int srclength, int pages) +{ + return msblk->decompressor->decompress(msblk, buffer, bh, b, offset, + length, srclength, pages); +} +#endif diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h index 9c2f76a..fe2587a 100644 --- a/fs/squashfs/squashfs.h +++ b/fs/squashfs/squashfs.h @@ -51,6 +51,9 @@ extern struct squashfs_cache_entry *squashfs_get_datablock(struct super_block *, u64, int); extern int squashfs_read_table(struct super_block *, void *, u64, int); +/* decompressor.c */ +extern const struct squashfs_decompressor *squashfs_lookup_decompressor(int); + /* export.c */ extern __le64 *squashfs_read_inode_lookup_table(struct super_block *, u64, unsigned int); @@ -70,14 +73,8 @@ extern struct inode *squashfs_iget(struct super_block *, long long, unsigned int); extern int squashfs_read_inode(struct inode *, long long); -/* zlib_wrapper.c */ -extern void *squashfs_zlib_init(void); -extern void squashfs_zlib_free(void *); -extern int squashfs_zlib_uncompress(struct squashfs_sb_info *, void **, - struct buffer_head **, int, int, int, int, int); - /* - * Inodes and files operations + * Inodes, files and decompressor operations */ /* dir.c */ @@ -94,3 +91,6 @@ extern const struct inode_operations squashfs_dir_inode_ops; /* symlink.c */ extern const struct address_space_operations squashfs_symlink_aops; + +/* zlib_wrapper.c */ +extern const struct squashfs_decompressor squashfs_zlib_comp_ops; diff --git a/fs/squashfs/squashfs_fs_sb.h b/fs/squashfs/squashfs_fs_sb.h index 23a67fa..7533350 100644 --- a/fs/squashfs/squashfs_fs_sb.h +++ b/fs/squashfs/squashfs_fs_sb.h @@ -52,25 +52,26 @@ struct squashfs_cache_entry { }; struct squashfs_sb_info { - int devblksize; - int devblksize_log2; - struct squashfs_cache *block_cache; - struct squashfs_cache *fragment_cache; - struct squashfs_cache *read_page; - int next_meta_index; - __le64 *id_table; - __le64 *fragment_index; - unsigned int *fragment_index_2; - struct mutex read_data_mutex; - struct mutex meta_index_mutex; - struct meta_index *meta_index; - void *stream; - __le64 *inode_lookup_table; - u64 inode_table; - u64 directory_table; - unsigned int block_size; - unsigned short block_log; - long long bytes_used; - unsigned int inodes; + const struct squashfs_decompressor *decompressor; + int devblksize; + int devblksize_log2; + struct squashfs_cache *block_cache; + struct squashfs_cache *fragment_cache; + struct squashfs_cache *read_page; + int next_meta_index; + __le64 *id_table; + __le64 *fragment_index; + unsigned int *fragment_index_2; + struct mutex read_data_mutex; + struct mutex meta_index_mutex; + struct meta_index *meta_index; + void *stream; + __le64 *inode_lookup_table; + u64 inode_table; + u64 directory_table; + unsigned int block_size; + unsigned short block_log; + long long bytes_used; + unsigned int inodes; }; #endif diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c index b9f8c6a..3550aec 100644 --- a/fs/squashfs/super.c +++ b/fs/squashfs/super.c @@ -41,27 +41,35 @@ #include "squashfs_fs_sb.h" #include "squashfs_fs_i.h" #include "squashfs.h" +#include "decompressor.h" static struct file_system_type squashfs_fs_type; static const struct super_operations squashfs_super_ops; -static int supported_squashfs_filesystem(short major, short minor, short comp) +static const struct squashfs_decompressor *supported_squashfs_filesystem(short + major, short minor, short id) { + const struct squashfs_decompressor *decompressor; + if (major < SQUASHFS_MAJOR) { ERROR("Major/Minor mismatch, older Squashfs %d.%d " "filesystems are unsupported\n", major, minor); - return -EINVAL; + return NULL; } else if (major > SQUASHFS_MAJOR || minor > SQUASHFS_MINOR) { ERROR("Major/Minor mismatch, trying to mount newer " "%d.%d filesystem\n", major, minor); ERROR("Please update your kernel\n"); - return -EINVAL; + return NULL; } - if (comp != ZLIB_COMPRESSION) - return -EINVAL; + decompressor = squashfs_lookup_decompressor(id); + if (!decompressor->supported) { + ERROR("Filesystem uses \"%s\" compression. This is not " + "supported\n", decompressor->name); + return NULL; + } - return 0; + return decompressor; } @@ -86,10 +94,6 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent) } msblk = sb->s_fs_info; - msblk->stream = squashfs_zlib_init(); - if (msblk->stream == NULL) - goto failure; - sblk = kzalloc(sizeof(*sblk), GFP_KERNEL); if (sblk == NULL) { ERROR("Failed to allocate squashfs_super_block\n"); @@ -116,25 +120,25 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent) goto failed_mount; } + err = -EINVAL; + /* Check it is a SQUASHFS superblock */ sb->s_magic = le32_to_cpu(sblk->s_magic); if (sb->s_magic != SQUASHFS_MAGIC) { if (!silent) ERROR("Can't find a SQUASHFS superblock on %s\n", bdevname(sb->s_bdev, b)); - err = -EINVAL; goto failed_mount; } - /* Check the MAJOR & MINOR versions and compression type */ - err = supported_squashfs_filesystem(le16_to_cpu(sblk->s_major), + /* Check the MAJOR & MINOR versions and lookup compression type */ + msblk->decompressor = supported_squashfs_filesystem( + le16_to_cpu(sblk->s_major), le16_to_cpu(sblk->s_minor), le16_to_cpu(sblk->compression)); - if (err < 0) + if (msblk->decompressor == NULL) goto failed_mount; - err = -EINVAL; - /* * Check if there's xattrs in the filesystem. These are not * supported in this version, so warn that they will be ignored. @@ -201,6 +205,10 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent) err = -ENOMEM; + msblk->stream = squashfs_decompressor_init(msblk); + if (msblk->stream == NULL) + goto failed_mount; + msblk->block_cache = squashfs_cache_init("metadata", SQUASHFS_CACHED_BLKS, SQUASHFS_METADATA_SIZE); if (msblk->block_cache == NULL) @@ -288,7 +296,7 @@ failed_mount: squashfs_cache_delete(msblk->block_cache); squashfs_cache_delete(msblk->fragment_cache); squashfs_cache_delete(msblk->read_page); - squashfs_zlib_free(msblk->stream); + squashfs_decompressor_free(msblk, msblk->stream); kfree(msblk->inode_lookup_table); kfree(msblk->fragment_index); kfree(msblk->id_table); @@ -298,7 +306,6 @@ failed_mount: return err; failure: - squashfs_zlib_free(msblk->stream); kfree(sb->s_fs_info); sb->s_fs_info = NULL; return -ENOMEM; @@ -342,7 +349,7 @@ static void squashfs_put_super(struct super_block *sb) squashfs_cache_delete(sbi->block_cache); squashfs_cache_delete(sbi->fragment_cache); squashfs_cache_delete(sbi->read_page); - squashfs_zlib_free(sbi->stream); + squashfs_decompressor_free(sbi, sbi->stream); kfree(sbi->id_table); kfree(sbi->fragment_index); kfree(sbi->meta_index); diff --git a/fs/squashfs/zlib_wrapper.c b/fs/squashfs/zlib_wrapper.c index c814594..4dd70e0 100644 --- a/fs/squashfs/zlib_wrapper.c +++ b/fs/squashfs/zlib_wrapper.c @@ -30,8 +30,9 @@ #include "squashfs_fs_sb.h" #include "squashfs_fs_i.h" #include "squashfs.h" +#include "decompressor.h" -void *squashfs_zlib_init() +static void *zlib_init(struct squashfs_sb_info *dummy) { z_stream *stream = kmalloc(sizeof(z_stream), GFP_KERNEL); if (stream == NULL) @@ -50,7 +51,7 @@ failed: } -void squashfs_zlib_free(void *strm) +static void zlib_free(void *strm) { z_stream *stream = strm; @@ -60,7 +61,7 @@ void squashfs_zlib_free(void *strm) } -int squashfs_zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer, +static int zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer, struct buffer_head **bh, int b, int offset, int length, int srclength, int pages) { @@ -137,3 +138,13 @@ release_mutex: return -EIO; } + +const struct squashfs_decompressor squashfs_zlib_comp_ops = { + .init = zlib_init, + .free = zlib_free, + .decompress = zlib_uncompress, + .id = ZLIB_COMPRESSION, + .name = "zlib", + .supported = 1 +}; + |