From 79cb8ced7eef53856b5a877db0544acf52e00c80 Mon Sep 17 00:00:00 2001 From: Chan Jeong Date: Thu, 5 Aug 2010 02:29:59 +0100 Subject: [PATCH] Squashfs: Add LZO compression support Signed-off-by: Chan Jeong Signed-off-by: Phillip Lougher --- fs/squashfs/Kconfig | 5 ++ fs/squashfs/Makefile | 2 +- fs/squashfs/decompressor.c | 6 ++ fs/squashfs/lzo_wrapper.c | 134 +++++++++++++++++++++++++++++++++++++ fs/squashfs/squashfs.h | 3 + 5 files changed, 149 insertions(+), 1 deletion(-) create mode 100644 fs/squashfs/lzo_wrapper.c diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig index 3e9ee95ef37d..3da01108c44e 100644 --- a/fs/squashfs/Kconfig +++ b/fs/squashfs/Kconfig @@ -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" diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile index 6fa6b9deecd3..7672bac8d328 100644 --- a/fs/squashfs/Makefile +++ b/fs/squashfs/Makefile @@ -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 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..e1f86ded0ee5 --- /dev/null +++ b/fs/squashfs/lzo_wrapper.c @@ -0,0 +1,134 @@ +/* + * Squashfs - a compressed read only filesystem for Linux + * + * Copyright (c) 2010 LG Electronics + * Chan Jeong + * + * 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 +#include +#include +#include +#include + +#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 +}; diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h index 733a17c42945..3a95ea68b00f 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_wrappers.c */ +extern const struct squashfs_decompressor squashfs_lzo_comp_ops;