+++ /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
-@@ -5,3 +5,4 @@
- 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_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 +1,151 @@
-+/*
-+ * 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 "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 / openwrt.git / blobdiff