diff options
Diffstat (limited to 'fs/squashfs/decompressor.c')
| -rw-r--r-- | fs/squashfs/decompressor.c | 89 |
1 files changed, 78 insertions, 11 deletions
diff --git a/fs/squashfs/decompressor.c b/fs/squashfs/decompressor.c index 24af9ce9722..ac22fe73b0a 100644 --- a/fs/squashfs/decompressor.c +++ b/fs/squashfs/decompressor.c @@ -2,7 +2,7 @@ * 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> + * 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 @@ -23,13 +23,14 @@ #include <linux/types.h> #include <linux/mutex.h> +#include <linux/slab.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" +#include "page_actor.h" /* * This file (and decompressor.h) implements a decompressor framework for @@ -37,27 +38,36 @@ */ static const struct squashfs_decompressor squashfs_lzma_unsupported_comp_ops = { - NULL, NULL, NULL, LZMA_COMPRESSION, "lzma", 0 + NULL, NULL, NULL, NULL, LZMA_COMPRESSION, "lzma", 0 }; #ifndef CONFIG_SQUASHFS_LZO -static const struct squashfs_decompressor squashfs_lzo_unsupported_comp_ops = { - NULL, NULL, NULL, LZO_COMPRESSION, "lzo", 0 +static const struct squashfs_decompressor squashfs_lzo_comp_ops = { + NULL, NULL, NULL, NULL, LZO_COMPRESSION, "lzo", 0 +}; +#endif + +#ifndef CONFIG_SQUASHFS_XZ +static const struct squashfs_decompressor squashfs_xz_comp_ops = { + NULL, NULL, NULL, NULL, XZ_COMPRESSION, "xz", 0 +}; +#endif + +#ifndef CONFIG_SQUASHFS_ZLIB +static const struct squashfs_decompressor squashfs_zlib_comp_ops = { + NULL, NULL, NULL, NULL, ZLIB_COMPRESSION, "zlib", 0 }; #endif static const struct squashfs_decompressor squashfs_unknown_comp_ops = { - NULL, NULL, NULL, 0, "unknown", 0 + NULL, NULL, NULL, NULL, 0, "unknown", 0 }; static const struct squashfs_decompressor *decompressor[] = { &squashfs_zlib_comp_ops, - &squashfs_lzma_unsupported_comp_ops, -#ifdef CONFIG_SQUASHFS_LZO &squashfs_lzo_comp_ops, -#else - &squashfs_lzo_unsupported_comp_ops, -#endif + &squashfs_xz_comp_ops, + &squashfs_lzma_unsupported_comp_ops, &squashfs_unknown_comp_ops }; @@ -72,3 +82,60 @@ const struct squashfs_decompressor *squashfs_lookup_decompressor(int id) return decompressor[i]; } + + +static void *get_comp_opts(struct super_block *sb, unsigned short flags) +{ + struct squashfs_sb_info *msblk = sb->s_fs_info; + void *buffer = NULL, *comp_opts; + struct squashfs_page_actor *actor = NULL; + int length = 0; + + /* + * Read decompressor specific options from file system if present + */ + if (SQUASHFS_COMP_OPTS(flags)) { + buffer = kmalloc(PAGE_CACHE_SIZE, GFP_KERNEL); + if (buffer == NULL) { + comp_opts = ERR_PTR(-ENOMEM); + goto out; + } + + actor = squashfs_page_actor_init(&buffer, 1, 0); + if (actor == NULL) { + comp_opts = ERR_PTR(-ENOMEM); + goto out; + } + + length = squashfs_read_data(sb, + sizeof(struct squashfs_super_block), 0, NULL, actor); + + if (length < 0) { + comp_opts = ERR_PTR(length); + goto out; + } + } + + comp_opts = squashfs_comp_opts(msblk, buffer, length); + +out: + kfree(actor); + kfree(buffer); + return comp_opts; +} + + +void *squashfs_decompressor_setup(struct super_block *sb, unsigned short flags) +{ + struct squashfs_sb_info *msblk = sb->s_fs_info; + void *stream, *comp_opts = get_comp_opts(sb, flags); + + if (IS_ERR(comp_opts)) + return comp_opts; + + stream = squashfs_decompressor_create(msblk, comp_opts); + if (IS_ERR(stream)) + kfree(comp_opts); + + return stream; +} |