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|
--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -2,7 +2,6 @@ config SQUASHFS
tristate "SquashFS 4.0 - Squashed file system support"
depends on BLOCK
select CRYPTO
- select CRYPTO_ZLIB
help
Saying Y here includes support for SquashFS 4.0 (a Compressed
Read-Only File System). Squashfs is a highly compressed read-only
@@ -37,6 +36,26 @@ config SQUASHFS_EMBEDDED
If unsure, say N.
+config SQUASHFS_SUPPORT_ZLIB
+ bool
+ prompt "Support ZLIB compression" if SQUASHFS_SUPPORT_LZMA
+ depends on SQUASHFS
+ select CRYPTO_ZLIB
+ default y
+ help
+ ZLIB is the default compression used in squashfs. If you are
+ using LZMA compression instead, you can remove support for ZLIB
+ entirely.
+
+config SQUASHFS_SUPPORT_LZMA
+ bool "Support LZMA compression"
+ depends on SQUASHFS
+ select CRYPTO_UNLZMA
+ help
+ By default SquashFS uses ZLIB compression, however (if your tools
+ support it, you can use LZMA instead, which saves space.
+
+
config SQUASHFS_FRAGMENT_CACHE_SIZE
int "Number of fragments cached" if SQUASHFS_EMBEDDED
depends on SQUASHFS
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -212,6 +212,7 @@ struct meta_index {
* definitions for structures on disk
*/
#define ZLIB_COMPRESSION 1
+#define LZMA_COMPRESSION 2
struct squashfs_super_block {
__le32 s_magic;
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -47,13 +47,65 @@
#include "squashfs.h"
-#define SQUASHFS_CRYPTO_ALG "zlib"
+static int squashfs_setup_zlib(struct squashfs_sb_info *msblk)
+{
+ int err = -EOPNOTSUPP;
+
+#ifdef CONFIG_SQUASHFS_SUPPORT_ZLIB
+ struct {
+ struct nlattr nla;
+ int val;
+ } params = {
+ .nla = {
+ .nla_len = nla_attr_size(sizeof(int)),
+ .nla_type = ZLIB_DECOMP_WINDOWBITS,
+ },
+ .val = DEF_WBITS,
+ };
+
+ msblk->tfm = crypto_alloc_pcomp("zlib", 0,
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(msblk->tfm)) {
+ ERROR("Failed to load zlib crypto module\n");
+ return PTR_ERR(msblk->tfm);
+ }
+
+ err = crypto_decompress_setup(msblk->tfm, ¶ms, sizeof(params));
+ if (err) {
+ ERROR("Failed to set up decompression parameters\n");
+ crypto_free_pcomp(msblk->tfm);
+ }
+#endif
+ return err;
+}
+
+static int squashfs_setup_lzma(struct squashfs_sb_info *msblk)
+{
+ int err = -EOPNOTSUPP;
+
+#ifdef CONFIG_SQUASHFS_SUPPORT_LZMA
+ msblk->tfm = crypto_alloc_pcomp("lzma", 0,
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(msblk->tfm)) {
+ ERROR("Failed to load lzma crypto module\n");
+ return PTR_ERR(msblk->tfm);
+ }
+
+ err = crypto_decompress_setup(msblk->tfm, NULL, 0);
+ if (err) {
+ ERROR("Failed to set up decompression parameters\n");
+ crypto_free_pcomp(msblk->tfm);
+ }
+#endif
+
+ return err;
+}
static struct file_system_type squashfs_fs_type;
static struct super_operations squashfs_super_ops;
-static int supported_squashfs_filesystem(short major, short minor, short comp)
+static int supported_squashfs_filesystem(short major, short minor)
{
if (major < SQUASHFS_MAJOR) {
ERROR("Major/Minor mismatch, older Squashfs %d.%d "
@@ -66,9 +118,6 @@ static int supported_squashfs_filesystem
return -EINVAL;
}
- if (comp != ZLIB_COMPRESSION)
- return -EINVAL;
-
return 0;
}
@@ -83,16 +132,6 @@ static int squashfs_fill_super(struct su
unsigned short flags;
unsigned int fragments;
u64 lookup_table_start;
- struct {
- struct nlattr nla;
- int val;
- } params = {
- .nla = {
- .nla_len = nla_attr_size(sizeof(int)),
- .nla_type = ZLIB_DECOMP_WINDOWBITS,
- },
- .val = DEF_WBITS,
- };
int err;
TRACE("Entered squashfs_fill_superblock\n");
@@ -104,21 +143,6 @@ static int squashfs_fill_super(struct su
}
msblk = sb->s_fs_info;
- msblk->tfm = crypto_alloc_pcomp(SQUASHFS_CRYPTO_ALG, 0,
- CRYPTO_ALG_ASYNC);
- if (IS_ERR(msblk->tfm)) {
- ERROR("Failed to load %s crypto module\n",
- SQUASHFS_CRYPTO_ALG);
- err = PTR_ERR(msblk->tfm);
- goto failed_pcomp;
- }
-
- err = crypto_decompress_setup(msblk->tfm, ¶ms, sizeof(params));
- if (err) {
- ERROR("Failed to set up decompression parameters\n");
- goto failure;
- }
-
sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
if (sblk == NULL) {
ERROR("Failed to allocate squashfs_super_block\n");
@@ -158,8 +182,21 @@ static int squashfs_fill_super(struct su
/* Check the MAJOR & MINOR versions and compression type */
err = supported_squashfs_filesystem(le16_to_cpu(sblk->s_major),
- le16_to_cpu(sblk->s_minor),
- le16_to_cpu(sblk->compression));
+ le16_to_cpu(sblk->s_minor));
+ if (err < 0)
+ goto failed_mount;
+
+ switch(le16_to_cpu(sblk->compression)) {
+ case ZLIB_COMPRESSION:
+ err = squashfs_setup_zlib(msblk);
+ break;
+ case LZMA_COMPRESSION:
+ err = squashfs_setup_lzma(msblk);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
if (err < 0)
goto failed_mount;
@@ -315,21 +352,16 @@ allocate_root:
return 0;
failed_mount:
+ if (msblk->tfm)
+ crypto_free_pcomp(msblk->tfm);
squashfs_cache_delete(msblk->block_cache);
squashfs_cache_delete(msblk->fragment_cache);
squashfs_cache_delete(msblk->read_page);
kfree(msblk->inode_lookup_table);
kfree(msblk->fragment_index);
kfree(msblk->id_table);
- crypto_free_pcomp(msblk->tfm);
- kfree(sb->s_fs_info);
- sb->s_fs_info = NULL;
kfree(sblk);
- return err;
-
failure:
- crypto_free_pcomp(msblk->tfm);
-failed_pcomp:
kfree(sb->s_fs_info);
sb->s_fs_info = NULL;
return err;
|
