diff options
| -rw-r--r-- | include/linux/decompress/unlzo.h | 10 | ||||
| -rw-r--r-- | init/Kconfig | 18 | ||||
| -rw-r--r-- | lib/decompress_unlzo.c | 209 | ||||
| -rw-r--r-- | lib/lzo/lzo1x_decompress.c | 9 | ||||
| -rw-r--r-- | scripts/Makefile.lib | 5 |
5 files changed, 244 insertions, 7 deletions
diff --git a/include/linux/decompress/unlzo.h b/include/linux/decompress/unlzo.h new file mode 100644 index 0000000..9872297 --- /dev/null +++ b/include/linux/decompress/unlzo.h @@ -0,0 +1,10 @@ +#ifndef DECOMPRESS_UNLZO_H +#define DECOMPRESS_UNLZO_H + +int unlzo(unsigned char *inbuf, int len, + int(*fill)(void*, unsigned int), + int(*flush)(void*, unsigned int), + unsigned char *output, + int *pos, + void(*error)(char *x)); +#endif diff --git a/init/Kconfig b/init/Kconfig index a23da9f..d95ca7c 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -115,10 +115,13 @@ config HAVE_KERNEL_BZIP2 config HAVE_KERNEL_LZMA bool +config HAVE_KERNEL_LZO + bool + choice prompt "Kernel compression mode" default KERNEL_GZIP - depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA + depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_LZO help The linux kernel is a kind of self-extracting executable. Several compression algorithms are available, which differ @@ -141,9 +144,8 @@ config KERNEL_GZIP bool "Gzip" depends on HAVE_KERNEL_GZIP help - The old and tried gzip compression. Its compression ratio is - the poorest among the 3 choices; however its speed (both - compression and decompression) is the fastest. + The old and tried gzip compression. It provides a good balance + between compression ratio and decompression speed. config KERNEL_BZIP2 bool "Bzip2" @@ -164,6 +166,14 @@ config KERNEL_LZMA two. Compression is slowest. The kernel size is about 33% smaller with LZMA in comparison to gzip. +config KERNEL_LZO + bool "LZO" + depends on HAVE_KERNEL_LZO + help + Its compression ratio is the poorest among the 4. The kernel + size is about about 10% bigger than gzip; however its speed + (both compression and decompression) is the fastest. + endchoice config SWAP diff --git a/lib/decompress_unlzo.c b/lib/decompress_unlzo.c new file mode 100644 index 0000000..db521f4 --- /dev/null +++ b/lib/decompress_unlzo.c @@ -0,0 +1,209 @@ +/* + * LZO decompressor for the Linux kernel. Code borrowed from the lzo + * implementation by Markus Franz Xaver Johannes Oberhumer. + * + * Linux kernel adaptation: + * Copyright (C) 2009 + * Albin Tonnerre, Free Electrons <albin.tonnerre@free-electrons.com> + * + * Original code: + * Copyright (C) 1996-2005 Markus Franz Xaver Johannes Oberhumer + * All Rights Reserved. + * + * lzop and the LZO library are free software; you can redistribute them + * and/or modify them under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, 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; see the file COPYING. + * If not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Markus F.X.J. Oberhumer + * <markus@oberhumer.com> + * http://www.oberhumer.com/opensource/lzop/ + */ + +#ifdef STATIC +#include "lzo/lzo1x_decompress.c" +#else +#include <linux/slab.h> +#include <linux/decompress/unlzo.h> +#endif + +#include <linux/types.h> +#include <linux/lzo.h> +#include <linux/decompress/mm.h> + +#include <linux/compiler.h> +#include <asm/unaligned.h> + +static const unsigned char lzop_magic[] = { + 0x89, 0x4c, 0x5a, 0x4f, 0x00, 0x0d, 0x0a, 0x1a, 0x0a }; + +#define LZO_BLOCK_SIZE (256*1024l) +#define HEADER_HAS_FILTER 0x00000800L + +STATIC inline int INIT parse_header(u8 *input, u8 *skip) +{ + int l; + u8 *parse = input; + u8 level = 0; + u16 version; + + /* read magic: 9 first bits */ + for (l = 0; l < 9; l++) { + if (*parse++ != lzop_magic[l]) + return 0; + } + /* get version (2bytes), skip library version (2), + * 'need to be extracted' version (2) and + * method (1) */ + version = get_unaligned_be16(parse); + parse += 7; + if (version >= 0x0940) + level = *parse++; + if (get_unaligned_be32(parse) & HEADER_HAS_FILTER) + parse += 8; /* flags + filter info */ + else + parse += 4; /* flags */ + + /* skip mode and mtime_low */ + parse += 8; + if (version >= 0x0940) + parse += 4; /* skip mtime_high */ + + l = *parse++; + /* don't care about the file name, and skip checksum */ + parse += l + 4; + + *skip = parse - input; + return 1; +} + +STATIC inline int INIT unlzo(u8 *input, int in_len, + int (*fill) (void *, unsigned int), + int (*flush) (void *, unsigned int), + u8 *output, int *posp, + void (*error_fn) (char *x)) +{ + u8 skip = 0, r = 0; + u32 src_len, dst_len; + size_t tmp; + u8 *in_buf, *in_buf_save, *out_buf; + int obytes_processed = 0; + + set_error_fn(error_fn); + + if (output) { + out_buf = output; + } else if (!flush) { + error("NULL output pointer and no flush function provided"); + goto exit; + } else { + out_buf = malloc(LZO_BLOCK_SIZE); + if (!out_buf) { + error("Could not allocate output buffer"); + goto exit; + } + } + + if (input && fill) { + error("Both input pointer and fill function provided, don't know what to do"); + goto exit_1; + } else if (input) { + in_buf = input; + } else if (!fill || !posp) { + error("NULL input pointer and missing position pointer or fill function"); + goto exit_1; + } else { + in_buf = malloc(lzo1x_worst_compress(LZO_BLOCK_SIZE)); + if (!in_buf) { + error("Could not allocate input buffer"); + goto exit_1; + } + } + in_buf_save = in_buf; + + if (posp) + *posp = 0; + + if (fill) + fill(in_buf, lzo1x_worst_compress(LZO_BLOCK_SIZE)); + + if (!parse_header(input, &skip)) { + error("invalid header"); + goto exit_2; + } + in_buf += skip; + + if (posp) + *posp = skip; + + for (;;) { + /* read uncompressed block size */ + dst_len = get_unaligned_be32(in_buf); + in_buf += 4; + + /* exit if last block */ + if (dst_len == 0) { + if (posp) + *posp += 4; + break; + } + + if (dst_len > LZO_BLOCK_SIZE) { + error("dest len longer than block size"); + goto exit_2; + } + + /* read compressed block size, and skip block checksum info */ + src_len = get_unaligned_be32(in_buf); + in_buf += 8; + + if (src_len <= 0 || src_len > dst_len) { + error("file corrupted"); + goto exit_2; + } + + /* decompress */ + tmp = dst_len; + r = lzo1x_decompress_safe((u8 *) in_buf, src_len, + out_buf, &tmp); + + if (r != LZO_E_OK || dst_len != tmp) { + error("Compressed data violation"); + goto exit_2; + } + + obytes_processed += dst_len; + if (flush) + flush(out_buf, dst_len); + if (output) + out_buf += dst_len; + if (posp) + *posp += src_len + 12; + if (fill) { + in_buf = in_buf_save; + fill(in_buf, lzo1x_worst_compress(LZO_BLOCK_SIZE)); + } else + in_buf += src_len; + } + +exit_2: + if (!input) + free(in_buf); +exit_1: + if (!output) + free(out_buf); +exit: + return obytes_processed; +} + +#define decompress unlzo diff --git a/lib/lzo/lzo1x_decompress.c b/lib/lzo/lzo1x_decompress.c index 5dc6b29..f2fd098 100644 --- a/lib/lzo/lzo1x_decompress.c +++ b/lib/lzo/lzo1x_decompress.c @@ -11,11 +11,13 @@ * Richard Purdie <rpurdie@openedhand.com> */ +#ifndef STATIC #include <linux/module.h> #include <linux/kernel.h> -#include <linux/lzo.h> -#include <asm/byteorder.h> +#endif + #include <asm/unaligned.h> +#include <linux/lzo.h> #include "lzodefs.h" #define HAVE_IP(x, ip_end, ip) ((size_t)(ip_end - ip) < (x)) @@ -244,9 +246,10 @@ lookbehind_overrun: *out_len = op - out; return LZO_E_LOOKBEHIND_OVERRUN; } - +#ifndef STATIC EXPORT_SYMBOL_GPL(lzo1x_decompress_safe); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("LZO1X Decompressor"); +#endif diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index cd815ac..0fe48cd 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -235,3 +235,8 @@ quiet_cmd_lzma = LZMA $@ cmd_lzma = (cat $(filter-out FORCE,$^) | \ lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) + +quiet_cmd_lzo = LZO $@ +cmd_lzo = (cat $(filter-out FORCE,$^) | \ + lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ + (rm -f $@ ; false) |
