[mtd-utils patch 1/2] Add lzo support to mtd-utils
Richard Purdie
rpurdie at openedhand.com
Tue Jul 10 11:03:31 EDT 2007
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 <rpurdie at openedhand.com>
---
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 <rpurdie at openedhand.com>
+ *
+ * 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 <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <asm/types.h>
+#include <linux/jffs2.h>
+#include <lzo1x.h>
+#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
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