Commit 062e27ec authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus 

* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  Squashfs: fix checkpatch.pl warnings
  Squashfs: fix filename typo
  Squashfs: update Kconfig and documentation for LZO
  Squashfs: fix block size use in LZO decompressor
  Squashfs: Add LZO compression support
  squashfs: fix filename in header comment
  Squashfs: Make XATTR config name consistent with other file systems
  squashfs: fix compiler inline warning
parents bf25db36 66048c38

Documentation/filesystems/squashfs.txt

+1 −1
Original line number Diff line number Diff line
@@ -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).

fs/squashfs/Kconfig

+20 −5
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 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
@@ -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
@@ -37,8 +37,23 @@ 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.



	  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

fs/squashfs/Makefile

+2 −2
Original line number Diff line number Diff line
@@ -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

fs/squashfs/decompressor.c

+6 −0
Original line number Diff line number Diff line
@@ -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

};

fs/squashfs/lzo_wrapper.c

0 → 100644
+136 −0
Original line number Diff line number Diff line 
/*

 * 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

};

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