Subject: [mtd-utils patch 1/2] Add lzo support to mtd-utils Add LZO support to mtd-utils to generate LZO compressed jffs2 images Unlike the kernel version, the standard lzo userspace library is used along with lzo1x_999_compress rather than the lzo1x_1_compress version since better compression ratios can be obtained (at no significant cost to decompression time). Signed-off-by: Richard Purdie --- Makefile | 3 - compr.c | 6 ++ compr.h | 6 ++ compr_lzo.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/jffs2.h | 1 5 files changed, 135 insertions(+), 1 deletion(-) Index: git/Makefile =================================================================== --- git.orig/Makefile 2007-03-01 11:57:58.000000000 +0000 +++ git/Makefile 2007-03-01 11:58:01.000000000 +0000 @@ -58,8 +58,9 @@ $(BUILDDIR)/mkfs.jffs2: $(BUILDDIR)/crc3 $(BUILDDIR)/compr_rtime.o \ $(BUILDDIR)/mkfs.jffs2.o \ $(BUILDDIR)/compr_zlib.o \ + $(BUILDDIR)/compr_lzo.o \ $(BUILDDIR)/compr.o - $(CC) $(LDFLAGS) -o $@ $^ -lz + $(CC) $(LDFLAGS) -o $@ $^ -lz -llzo $(BUILDDIR)/flash_eraseall: $(BUILDDIR)/crc32.o $(BUILDDIR)/flash_eraseall.o $(CC) $(LDFLAGS) -o $@ $^ Index: git/compr.c =================================================================== --- git.orig/compr.c 2007-03-01 11:57:58.000000000 +0000 +++ git/compr.c 2007-03-01 11:58:01.000000000 +0000 @@ -474,6 +474,9 @@ int jffs2_compressors_init(void) #ifdef CONFIG_JFFS2_RTIME jffs2_rtime_init(); #endif +#ifdef CONFIG_JFFS2_LZO + jffs2_lzo_init(); +#endif return 0; } @@ -485,5 +488,8 @@ int jffs2_compressors_exit(void) #ifdef CONFIG_JFFS2_ZLIB jffs2_zlib_exit(); #endif +#ifdef CONFIG_JFFS2_LZO + jffs2_lzo_exit(); +#endif return 0; } Index: git/compr.h =================================================================== --- git.orig/compr.h 2007-03-01 11:57:58.000000000 +0000 +++ git/compr.h 2007-03-01 11:58:01.000000000 +0000 @@ -21,11 +21,13 @@ #define CONFIG_JFFS2_ZLIB #define CONFIG_JFFS2_RTIME +#define CONFIG_JFFS2_LZO #define JFFS2_RUBINMIPS_PRIORITY 10 #define JFFS2_DYNRUBIN_PRIORITY 20 #define JFFS2_RTIME_PRIORITY 50 #define JFFS2_ZLIB_PRIORITY 60 +#define JFFS2_LZO_PRIORITY 80 #define JFFS2_COMPR_MODE_NONE 0 #define JFFS2_COMPR_MODE_PRIORITY 1 @@ -111,5 +113,9 @@ void jffs2_zlib_exit(void); int jffs2_rtime_init(void); void jffs2_rtime_exit(void); #endif +#ifdef CONFIG_JFFS2_LZO +int jffs2_lzo_init(void); +void jffs2_lzo_exit(void); +#endif #endif /* __JFFS2_COMPR_H__ */ Index: git/compr_lzo.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ git/compr_lzo.c 2007-03-01 11:58:01.000000000 +0000 @@ -0,0 +1,120 @@ +/* + * JFFS2 LZO Compression Interface. + * + * Copyright (C) 2007 Nokia Corporation. All rights reserved. + * + * Author: Richard Purdie + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * 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, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + * + */ + +#include +#include +#include +#include +#include +#include +#include "compr.h" + +extern int page_size; + +static void *lzo_mem; +static void *lzo_compress_buf; + +/* + * Note about LZO compression. + * + * We want to use the _999_ compression routine which gives better compression + * rates at the expense of time. Decompression time is unaffected. We might as + * well use the standard lzo library routines for this but they will overflow + * the destination buffer since they don't check the destination size. + * + * We therefore compress to a temporary buffer and copy if it will fit. + * + */ +static int jffs2_lzo_cmpr(unsigned char *data_in, unsigned char *cpage_out, + uint32_t *sourcelen, uint32_t *dstlen, void *model) +{ + uint32_t compress_size; + int ret; + + ret = lzo1x_999_compress(data_in, *sourcelen, lzo_compress_buf, &compress_size, lzo_mem); + + if (ret != LZO_E_OK) + return -1; + + if (compress_size > *dstlen) + return -1; + + memcpy(cpage_out, lzo_compress_buf, compress_size); + *dstlen = compress_size; + + return 0; +} + +static int jffs2_lzo_decompress(unsigned char *data_in, unsigned char *cpage_out, + uint32_t srclen, uint32_t destlen, void *model) +{ + int ret; + uint32_t dl; + + ret = lzo1x_decompress_safe(data_in,srclen,cpage_out,&dl,NULL); + + if (ret != LZO_E_OK || dl != destlen) + return -1; + + return 0; +} + +static struct jffs2_compressor jffs2_lzo_comp = { + .priority = JFFS2_LZO_PRIORITY, + .name = "lzo", + .compr = JFFS2_COMPR_LZO, + .compress = &jffs2_lzo_cmpr, + .decompress = &jffs2_lzo_decompress, + .disabled = 0, +}; + +int jffs2_lzo_init(void) +{ + int ret; + + lzo_mem = malloc(LZO1X_999_MEM_COMPRESS); + if (!lzo_mem) + return -1; + + /* Worse case LZO compression size from their FAQ */ + lzo_compress_buf = malloc(page_size + (page_size / 64) + 16 + 3); + if (!lzo_compress_buf) { + free(lzo_mem); + return -1; + } + + ret = jffs2_register_compressor(&jffs2_lzo_comp); + if (ret < 0) { + free(lzo_compress_buf); + free(lzo_mem); + } + + return ret; +} + +void jffs2_lzo_exit(void) +{ + jffs2_unregister_compressor(&jffs2_lzo_comp); + free(lzo_compress_buf); + free(lzo_mem); +} Index: git/include/linux/jffs2.h =================================================================== --- git.orig/include/linux/jffs2.h 2007-03-01 11:57:58.000000000 +0000 +++ git/include/linux/jffs2.h 2007-03-01 11:58:01.000000000 +0000 @@ -46,6 +46,7 @@ #define JFFS2_COMPR_COPY 0x04 #define JFFS2_COMPR_DYNRUBIN 0x05 #define JFFS2_COMPR_ZLIB 0x06 +#define JFFS2_COMPR_LZO 0x07 /* Compatibility flags. */ #define JFFS2_COMPAT_MASK 0xc000 /* What do to if an unknown nodetype is found */ #define JFFS2_NODE_ACCURATE 0x2000