Squashfs: Add LZO compression support (79cb8ced) · Commits · e / devices / android_kernel_fairphone_FP5

fs/squashfs/Kconfig

+5 −0

Original line number	Diff line number	Diff line
		@@ -37,6 +37,11 @@ config SQUASHFS_XATTR

		If unsure, say N.

		config SQUASHFS_LZO
		bool "Include support for LZO compressed file systems"
		depends on SQUASHFS
		select LZO_DECOMPRESS

		config SQUASHFS_EMBEDDED

		bool "Additional option for memory-constrained systems"

fs/squashfs/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -6,4 +6,4 @@ obj-$(CONFIG_SQUASHFS) += squashfs.o
		squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o
		squashfs-y += namei.o super.o symlink.o zlib_wrapper.o decompressor.o
		squashfs-$(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

+134 −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)
		{
		struct squashfs_lzo stream = kzalloc(sizeof(stream), GFP_KERNEL);
		if (stream == NULL)
		goto failed;
		stream->input = vmalloc(msblk->block_size);
		if (stream->input == NULL)
		goto failed;
		stream->output = vmalloc(msblk->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 = msblk->block_size;

		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
		};

fs/squashfs/squashfs.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -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_wrappers.c */
		extern const struct squashfs_decompressor squashfs_lzo_comp_ops;