Commit e631ddba authored by Ferenc Havasi's avatar Ferenc Havasi Committed by Thomas Gleixner
Browse files

[JFFS2] Add erase block summary support (mount time improvement) 



The goal of summary is to speed up the mount time. Erase block summary (EBS)
stores summary information at the end of every (closed) erase block. It is
no longer necessary to scan all nodes separetly (and read all pages of them)
just read this "small" summary, where every information is stored which is
needed at mount time.

This summary information is stored in a JFFS2_FEATURE_RWCOMPAT_DELETE. During
the mount process if there is no summary info the orignal scan process will
be executed. EBS works with NAND and NOR flashes, too.

There is a user space tool called sumtool to generate this summary
information for a JFFS2 image.

Signed-off-by: default avatarFerenc Havasi <havasi@inf.u-szeged.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 15017876

fs/Kconfig

+13 −0
Original line number Diff line number Diff line
@@ -1050,6 +1050,19 @@ config JFFS2_FS_WRITEBUFFER 
	    - NOR flash with transparent ECC

	    - DataFlash



config JFFS2_SUMMARY

	bool "JFFS2 summary support (EXPERIMENTAL)"

	depends on JFFS2_FS && EXPERIMENTAL

	default n

	help

	  This feature makes it possible to use summary information

	  for faster filesystem mount.



	  The summary information can be inserted into a filesystem image

	  by the utility 'sumtool'.



	  If unsure, say 'N'.



config JFFS2_COMPRESSION_OPTIONS

	bool "Advanced compression options for JFFS2"

	depends on JFFS2_FS

fs/jffs2/Makefile

+2 −1
Original line number Diff line number Diff line 
#

# Makefile for the Linux Journalling Flash File System v2 (JFFS2)

#

# $Id: Makefile.common,v 1.10 2005/07/17 06:56:20 dedekind Exp $

# $Id: Makefile.common,v 1.11 2005/09/07 08:34:53 havasi Exp $

#



obj-$(CONFIG_JFFS2_FS) += jffs2.o
@@ -15,3 +15,4 @@ jffs2-$(CONFIG_JFFS2_FS_WRITEBUFFER) += wbuf.o 
jffs2-$(CONFIG_JFFS2_RUBIN)	+= compr_rubin.o

jffs2-$(CONFIG_JFFS2_RTIME)	+= compr_rtime.o

jffs2-$(CONFIG_JFFS2_ZLIB)	+= compr_zlib.o

jffs2-$(CONFIG_JFFS2_SUMMARY)   += summary.o

fs/jffs2/build.c

+8 −4
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
 *

 * For licensing information, see the file 'LICENCE' in this directory.

 *

 * $Id: build.c,v 1.77 2005/08/31 13:51:00 havasi Exp $

 * $Id: build.c,v 1.78 2005/09/07 08:34:54 havasi Exp $

 *

 */
@@ -350,6 +350,10 @@ int jffs2_do_mount_fs(struct jffs2_sb_info *c) 
	INIT_LIST_HEAD(&c->bad_list);

	INIT_LIST_HEAD(&c->bad_used_list);

	c->highest_ino = 1;

	c->summary = NULL;



	if (jffs2_sum_init(c))

		return -ENOMEM;



	if (jffs2_build_filesystem(c)) {

		D1(printk(KERN_DEBUG "build_fs failed\n"));

fs/jffs2/debug.h

+9 −1
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
 *

 * For licensing information, see the file 'LICENCE' in this directory.

 *

 * $Id: debug.h,v 1.14 2005/08/17 13:48:59 dedekind Exp $

 * $Id: debug.h,v 1.15 2005/09/07 08:34:54 havasi Exp $

 *

 */

#ifndef _JFFS2_DEBUG_H_
@@ -28,6 +28,7 @@ 
#define JFFS2_DBG_DENTLIST_MESSAGES

#define JFFS2_DBG_NODEREF_MESSAGES

#define JFFS2_DBG_INOCACHE_MESSAGES

#define JFFS2_DBG_SUMMARY_MESSAGES

#endif



#if CONFIG_JFFS2_FS_DEBUG == 2
@@ -137,6 +138,13 @@ 
#define JFFS2_DBG_INOCACHE(fmt, ...)

#endif



/* Summary debugging messages */

#ifdef JFFS2_DBG_SUMMARY_MESSAGES

#define JFFS2_DBG_SUMMARY(fmt, ...)	JFFS2_DEBUG(fmt, ##__VA_ARGS__)

#else

#define JFFS2_DBG_SUMMARY(fmt, ...)

#endif



/* Watch the object allocations */

#ifdef JFFS2_DBG_MEMALLOC_MESSAGES

#define JFFS2_DBG_MEMALLOC(fmt, ...)	JFFS2_DEBUG(fmt, ##__VA_ARGS__)

fs/jffs2/dir.c

+13 −7
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
 *

 * For licensing information, see the file 'LICENCE' in this directory.

 *

 * $Id: dir.c,v 1.88 2005/08/17 13:46:22 dedekind Exp $

 * $Id: dir.c,v 1.89 2005/09/07 08:34:54 havasi Exp $

 *

 */
@@ -310,7 +310,8 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char 
	 * Just the node will do for now, though 

	 */

	namelen = dentry->d_name.len;

	ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &phys_ofs, &alloclen, ALLOC_NORMAL);

	ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &phys_ofs, &alloclen,

				ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);



	if (ret) {

		jffs2_free_raw_inode(ri);
@@ -370,7 +371,8 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char 
	up(&f->sem);



	jffs2_complete_reservation(c);

	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen, ALLOC_NORMAL);

	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,

				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));

	if (ret) {

		/* Eep. */

		jffs2_clear_inode(inode);
@@ -455,7 +457,8 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, int mode) 
	 * Just the node will do for now, though 

	 */

	namelen = dentry->d_name.len;

	ret = jffs2_reserve_space(c, sizeof(*ri), &phys_ofs, &alloclen, ALLOC_NORMAL);

	ret = jffs2_reserve_space(c, sizeof(*ri), &phys_ofs, &alloclen, ALLOC_NORMAL,

				JFFS2_SUMMARY_INODE_SIZE);



	if (ret) {

		jffs2_free_raw_inode(ri);
@@ -498,7 +501,8 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, int mode) 
	up(&f->sem);



	jffs2_complete_reservation(c);

	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen, ALLOC_NORMAL);

	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,

				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));

	if (ret) {

		/* Eep. */

		jffs2_clear_inode(inode);
@@ -607,7 +611,8 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, int mode, de 
	 * Just the node will do for now, though 

	 */

	namelen = dentry->d_name.len;

	ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &phys_ofs, &alloclen, ALLOC_NORMAL);

	ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &phys_ofs, &alloclen,

				ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);



	if (ret) {

		jffs2_free_raw_inode(ri);
@@ -652,7 +657,8 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, int mode, de 
	up(&f->sem);



	jffs2_complete_reservation(c);

	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen, ALLOC_NORMAL);

	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,

				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));

	if (ret) {

		/* Eep. */

		jffs2_clear_inode(inode);

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