9 files changed, 181 insertions, 21 deletions

diff --git a/Documentation/filesystems/squashfs.txt b/Documentation/filesystems/squashfs.txt
index 203f7202cc9e..66699afd66ca 100644
--- a/Documentation/filesystems/squashfs.txt
+++ b/Documentation/filesystems/squashfs.txt
@@ -2,7 +2,7 @@ SQUASHFS 4.0 FILESYSTEM
 =======================
 
 Squashfs is a compressed read-only filesystem for Linux.
-It uses zlib compression to compress files, inodes and directories.
+It uses zlib/lzo compression to compress files, inodes and directories.
 Inodes in the system are very small and all blocks are packed to minimise
 data overhead. Block sizes greater than 4K are supported up to a maximum
 of 1Mbytes (default block size 128K).
diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
index cc6ce8a84c21..e5f63da64d04 100644
--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -5,13 +5,13 @@ config SQUASHFS
         help
           Saying Y here includes support for SquashFS 4.0 (a Compressed
           Read-Only File System).  Squashfs is a highly compressed read-only
-          filesystem for Linux.  It uses zlib compression to compress both
+          filesystem for Linux.  It uses zlib/lzo compression to compress both
           files, inodes and directories.  Inodes in the system are very small
           and all blocks are packed to minimise data overhead. Block sizes
           greater than 4K are supported up to a maximum of 1 Mbytes (default
           block size 128K).  SquashFS 4.0 supports 64 bit filesystems and files
           (larger than 4GB), full uid/gid information, hard links and
-          timestamps.  
+          timestamps.
 
           Squashfs is intended for general read-only filesystem use, for
           archival use (i.e. in cases where a .tar.gz file may be used), and in
@@ -26,7 +26,7 @@ config SQUASHFS
 
           If unsure, say N.
 
-config SQUASHFS_XATTRS
+config SQUASHFS_XATTR
         bool "Squashfs XATTR support"
         depends on SQUASHFS
         default n
@@ -37,9 +37,24 @@ config SQUASHFS_XATTRS
 
           If unsure, say N.
 
-config SQUASHFS_EMBEDDED
+config SQUASHFS_LZO
+        bool "Include support for LZO compressed file systems"
+        depends on SQUASHFS
+        default n
+        select LZO_DECOMPRESS
+        help
+          Saying Y here includes support for reading Squashfs file systems
+          compressed with LZO compresssion.  LZO compression is mainly
+          aimed at embedded systems with slower CPUs where the overheads
+          of zlib are too high.
 
-        bool "Additional option for memory-constrained systems" 
+          LZO is not the standard compression used in Squashfs and so most
+          file systems will be readable without selecting this option.
+
+          If unsure, say N.
+
+config SQUASHFS_EMBEDDED
+        bool "Additional option for memory-constrained systems"
         depends on SQUASHFS
         default n
         help
diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile
index 2cee3e9fa452..7672bac8d328 100644
--- a/fs/squashfs/Makefile
+++ b/fs/squashfs/Makefile
@@ -5,5 +5,5 @@
 obj-$(CONFIG_SQUASHFS) += squashfs.o
 squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o
 squashfs-y += namei.o super.o symlink.o zlib_wrapper.o decompressor.o
-squashfs-$(CONFIG_SQUASHFS_XATTRS) += xattr.o xattr_id.o
-
+squashfs-$(CONFIG_SQUASHFS_XATTR) += xattr.o xattr_id.o
+squashfs-$(CONFIG_SQUASHFS_LZO) += lzo_wrapper.o
diff --git a/fs/squashfs/decompressor.c b/fs/squashfs/decompressor.c
index 157478da6ac9..24af9ce9722f 100644
--- a/fs/squashfs/decompressor.c
+++ b/fs/squashfs/decompressor.c
@@ -40,9 +40,11 @@ static const struct squashfs_decompressor squashfs_lzma_unsupported_comp_ops = {
         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
 };
+#endif
 
 static const struct squashfs_decompressor squashfs_unknown_comp_ops = {
         NULL, NULL, NULL, 0, "unknown", 0
@@ -51,7 +53,11 @@ static const struct squashfs_decompressor squashfs_unknown_comp_ops = {
 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_unknown_comp_ops
 };
 
diff --git a/fs/squashfs/lzo_wrapper.c b/fs/squashfs/lzo_wrapper.c
new file mode 100644
index 000000000000..5d87789bf1c1
--- /dev/null
+++ b/fs/squashfs/lzo_wrapper.c
@@ -0,0 +1,136 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2010 LG Electronics
+ * Chan Jeong <chan.jeong@lge.com>
+ *
+ * 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.
+ *
+ * lzo_wrapper.c
+ */
+
+#include <linux/mutex.h>
+#include <linux/buffer_head.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/lzo.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+#include "decompressor.h"
+
+struct squashfs_lzo {
+        void    *input;
+        void    *output;
+};
+
+static void *lzo_init(struct squashfs_sb_info *msblk)
+{
+        int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE);
+
+        struct squashfs_lzo *stream = kzalloc(sizeof(*stream), GFP_KERNEL);
+        if (stream == NULL)
+                goto failed;
+        stream->input = vmalloc(block_size);
+        if (stream->input == NULL)
+                goto failed;
+        stream->output = vmalloc(block_size);
+        if (stream->output == NULL)
+                goto failed2;
+
+        return stream;
+
+failed2:
+        vfree(stream->input);
+failed:
+        ERROR("Failed to allocate lzo workspace\n");
+        kfree(stream);
+        return NULL;
+}
+
+
+static void lzo_free(void *strm)
+{
+        struct squashfs_lzo *stream = strm;
+
+        if (stream) {
+                vfree(stream->input);
+                vfree(stream->output);
+        }
+        kfree(stream);
+}
+
+
+static int lzo_uncompress(struct squashfs_sb_info *msblk, void **buffer,
+        struct buffer_head **bh, int b, int offset, int length, int srclength,
+        int pages)
+{
+        struct squashfs_lzo *stream = msblk->stream;
+        void *buff = stream->input;
+        int avail, i, bytes = length, res;
+        size_t out_len = srclength;
+
+        mutex_lock(&msblk->read_data_mutex);
+
+        for (i = 0; i < b; i++) {
+                wait_on_buffer(bh[i]);
+                if (!buffer_uptodate(bh[i]))
+                        goto block_release;
+
+                avail = min(bytes, msblk->devblksize - offset);
+                memcpy(buff, bh[i]->b_data + offset, avail);
+                buff += avail;
+                bytes -= avail;
+                offset = 0;
+                put_bh(bh[i]);
+        }
+
+        res = lzo1x_decompress_safe(stream->input, (size_t)length,
+                                        stream->output, &out_len);
+        if (res != LZO_E_OK)
+                goto failed;
+
+        res = bytes = (int)out_len;
+        for (i = 0, buff = stream->output; bytes && i < pages; i++) {
+                avail = min_t(int, bytes, PAGE_CACHE_SIZE);
+                memcpy(buffer[i], buff, avail);
+                buff += avail;
+                bytes -= avail;
+        }
+
+        mutex_unlock(&msblk->read_data_mutex);
+        return res;
+
+block_release:
+        for (; i < b; i++)
+                put_bh(bh[i]);
+
+failed:
+        mutex_unlock(&msblk->read_data_mutex);
+
+        ERROR("lzo decompression failed, data probably corrupt\n");
+        return -EIO;
+}
+
+const struct squashfs_decompressor squashfs_lzo_comp_ops = {
+        .init = lzo_init,
+        .free = lzo_free,
+        .decompress = lzo_uncompress,
+        .id = LZO_COMPRESSION,
+        .name = "lzo",
+        .supported = 1
+};
diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h
index 733a17c42945..5d45569d5f72 100644
--- a/fs/squashfs/squashfs.h
+++ b/fs/squashfs/squashfs.h
@@ -104,3 +104,6 @@ extern const struct xattr_handler *squashfs_xattr_handlers[];
 
 /* zlib_wrapper.c */
 extern const struct squashfs_decompressor squashfs_zlib_comp_ops;
+
+/* lzo_wrapper.c */
+extern const struct squashfs_decompressor squashfs_lzo_comp_ops;
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index 8eabb808b78d..c5137fc9ab11 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -274,7 +274,7 @@ struct squashfs_base_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
 };
 
 struct squashfs_ipc_inode {
@@ -283,7 +283,7 @@ struct squashfs_ipc_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  nlink;
 };
 
@@ -293,7 +293,7 @@ struct squashfs_lipc_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  nlink;
         __le32                  xattr;
 };
@@ -304,7 +304,7 @@ struct squashfs_dev_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  nlink;
         __le32                  rdev;
 };
@@ -315,7 +315,7 @@ struct squashfs_ldev_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  nlink;
         __le32                  rdev;
         __le32                  xattr;
@@ -327,7 +327,7 @@ struct squashfs_symlink_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  nlink;
         __le32                  symlink_size;
         char                    symlink[0];
@@ -339,7 +339,7 @@ struct squashfs_reg_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  start_block;
         __le32                  fragment;
         __le32                  offset;
@@ -353,7 +353,7 @@ struct squashfs_lreg_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le64                  start_block;
         __le64                  file_size;
         __le64                  sparse;
@@ -370,7 +370,7 @@ struct squashfs_dir_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  start_block;
         __le32                  nlink;
         __le16                  file_size;
@@ -384,7 +384,7 @@ struct squashfs_ldir_inode {
         __le16                  uid;
         __le16                  guid;
         __le32                  mtime;
-        __le32                  inode_number;
+        __le32                  inode_number;
         __le32                  nlink;
         __le32                  file_size;
         __le32                  start_block;
diff --git a/fs/squashfs/xattr.c b/fs/squashfs/xattr.c
index c7655e8b31cd..652b8541f9c6 100644
--- a/fs/squashfs/xattr.c
+++ b/fs/squashfs/xattr.c
@@ -18,7 +18,7 @@
  * along with this program; if not, write to the Free Software
  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  *
- * xattr_id.c
+ * xattr.c
  */
 
 #include <linux/init.h>
@@ -295,7 +295,7 @@ static const struct xattr_handler squashfs_xattr_security_handler = {
         .get    = squashfs_security_get
 };
 
-static inline const struct xattr_handler *squashfs_xattr_handler(int type)
+static const struct xattr_handler *squashfs_xattr_handler(int type)
 {
         if (type & ~(SQUASHFS_XATTR_PREFIX_MASK | SQUASHFS_XATTR_VALUE_OOL))
                 /* ignore unrecognised type */
diff --git a/fs/squashfs/xattr.h b/fs/squashfs/xattr.h
index 9da071ae181c..49fe0d719fbf 100644
--- a/fs/squashfs/xattr.h
+++ b/fs/squashfs/xattr.h
@@ -21,7 +21,7 @@
  * xattr.h
  */
 
-#ifdef CONFIG_SQUASHFS_XATTRS
+#ifdef CONFIG_SQUASHFS_XATTR
 extern __le64 *squashfs_read_xattr_id_table(struct super_block *, u64,
                 u64 *, int *);
 extern int squashfs_xattr_lookup(struct super_block *, unsigned int, int *,