--- /dev/null
+From f49e1efdd179d54e814ff2a8e8f469496583062c Mon Sep 17 00:00:00 2001
+From: Phillip Lougher <phillip@lougher.demon.co.uk>
+Date: Tue, 20 Oct 2009 10:54:36 +0100
+Subject: [PATCH] Squashfs: add LZMA compression
+
+Add support for LZMA compressed filesystems. This is an initial
+implementation.
+
+Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
+---
+ fs/squashfs/Kconfig | 5 ++
+ fs/squashfs/Makefile | 1 +
+ fs/squashfs/decompressor.c | 4 +
+ fs/squashfs/lzma_wrapper.c | 151 ++++++++++++++++++++++++++++++++++++++++++++
+ fs/squashfs/squashfs.h | 3 +
+ 5 files changed, 164 insertions(+), 0 deletions(-)
+ create mode 100644 fs/squashfs/lzma_wrapper.c
+
+--- a/fs/squashfs/Kconfig
++++ b/fs/squashfs/Kconfig
+@@ -26,6 +26,11 @@ config SQUASHFS
+
+ If unsure, say N.
+
++config SQUASHFS_LZMA
++ bool "Include support for LZMA compressed file systems"
++ depends on SQUASHFS
++ select DECOMPRESS_LZMA
++
+ config SQUASHFS_EMBEDDED
+
+ bool "Additional option for memory-constrained systems"
+--- 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_LZMA) += lzma_wrapper.o
+
+--- a/fs/squashfs/decompressor.c
++++ b/fs/squashfs/decompressor.c
+@@ -50,7 +50,11 @@ static const struct squashfs_decompresso
+
+ static const struct squashfs_decompressor *decompressor[] = {
+ &squashfs_zlib_comp_ops,
++#ifdef CONFIG_SQUASHFS_LZMA
++ &squashfs_lzma_comp_ops,
++#else
+ &squashfs_lzma_unsupported_comp_ops,
++#endif
+ &squashfs_lzo_unsupported_comp_ops,
+ &squashfs_unknown_comp_ops
+ };
+--- /dev/null
++++ b/fs/squashfs/lzma_wrapper.c
+@@ -0,0 +1,152 @@
++/*
++ * 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>
++ *
++ * 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.
++ *
++ * lzma_wrapper.c
++ */
++
++#include <asm/unaligned.h>
++#include <linux/buffer_head.h>
++#include <linux/mutex.h>
++#include <linux/vmalloc.h>
++#include <linux/decompress/unlzma.h>
++#include <linux/slab.h>
++
++#include "squashfs_fs.h"
++#include "squashfs_fs_sb.h"
++#include "squashfs_fs_i.h"
++#include "squashfs.h"
++#include "decompressor.h"
++
++struct squashfs_lzma {
++ void *input;
++ void *output;
++};
++
++/* decompress_unlzma.c is currently non re-entrant... */
++DEFINE_MUTEX(lzma_mutex);
++
++/* decompress_unlzma.c doesn't provide any context in its callbacks... */
++static int lzma_error;
++
++static void error(char *m)
++{
++ ERROR("unlzma error: %s\n", m);
++ lzma_error = 1;
++}
++
++
++static void *lzma_init(struct squashfs_sb_info *msblk)
++{
++ struct squashfs_lzma *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 lzma workspace\n");
++ kfree(stream);
++ return NULL;
++}
++
++
++static void lzma_free(void *strm)
++{
++ struct squashfs_lzma *stream = strm;
++
++ if (stream) {
++ vfree(stream->input);
++ vfree(stream->output);
++ }
++ kfree(stream);
++}
++
++
++static int lzma_uncompress(struct squashfs_sb_info *msblk, void **buffer,
++ struct buffer_head **bh, int b, int offset, int length, int srclength,
++ int pages)
++{
++ struct squashfs_lzma *stream = msblk->stream;
++ void *buff = stream->input;
++ int avail, i, bytes = length, res;
++
++ mutex_lock(&lzma_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]);
++ }
++
++ lzma_error = 0;
++ res = unlzma(stream->input, length, NULL, NULL, stream->output, NULL,
++ error);
++ if (res || lzma_error)
++ goto failed;
++
++ /* uncompressed size is stored in the LZMA header (5 byte offset) */
++ res = bytes = get_unaligned_le32(stream->input + 5);
++ 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;
++ }
++ if (bytes)
++ goto failed;
++
++ mutex_unlock(&lzma_mutex);
++ return res;
++
++block_release:
++ for (; i < b; i++)
++ put_bh(bh[i]);
++
++failed:
++ mutex_unlock(&lzma_mutex);
++
++ ERROR("lzma decompression failed, data probably corrupt\n");
++ return -EIO;
++}
++
++const struct squashfs_decompressor squashfs_lzma_comp_ops = {
++ .init = lzma_init,
++ .free = lzma_free,
++ .decompress = lzma_uncompress,
++ .id = LZMA_COMPRESSION,
++ .name = "lzma",
++ .supported = 1
++};
++
+--- a/fs/squashfs/squashfs.h
++++ b/fs/squashfs/squashfs.h
+@@ -94,3 +94,6 @@ extern const struct address_space_operat
+
+ /* zlib_wrapper.c */
+ extern const struct squashfs_decompressor squashfs_zlib_comp_ops;
++
++/* lzma wrapper.c */
++extern const struct squashfs_decompressor squashfs_lzma_comp_ops;
projects / openwrt / svn-archive / archive.git / blobdiff