[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: Ferenc Havasi <havasi@inf.u-szeged.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

20 files changed, 1395 insertions, 199 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index 01a2952..37d86c5 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -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
diff --git a/fs/jffs2/Makefile b/fs/jffs2/Makefile
index e6230f1..77dc556 100644
--- a/fs/jffs2/Makefile
+++ b/fs/jffs2/Makefile
@@ -1,7 +1,7 @@
 #
 # 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
diff --git a/fs/jffs2/build.c b/fs/jffs2/build.c
index 1522eac..f4a47a3 100644
--- a/fs/jffs2/build.c
+++ b/fs/jffs2/build.c
@@ -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"));
@@ -357,11 +361,11 @@ int jffs2_do_mount_fs(struct jffs2_sb_info *c)
 		jffs2_free_raw_node_refs(c);
 #ifndef __ECOS
 		if (jffs2_blocks_use_vmalloc(c))
-                    vfree(c->blocks);
+			vfree(c->blocks);
 		else 
 #endif
-                    kfree(c->blocks);
-		
+			kfree(c->blocks);
+
 		return -EIO;
 	}
 
diff --git a/fs/jffs2/debug.h b/fs/jffs2/debug.h
index 03d9626..60e5dbb 100644
--- a/fs/jffs2/debug.h
+++ b/fs/jffs2/debug.h
@@ -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__)
diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c
index 0fd15aa..19bea0f 100644
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -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);
diff --git a/fs/jffs2/file.c b/fs/jffs2/file.c
index 8279bf0..231404a 100644
--- a/fs/jffs2/file.c
+++ b/fs/jffs2/file.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: file.c,v 1.102 2005/07/06 12:13:09 dwmw2 Exp $
+ * $Id: file.c,v 1.103 2005/09/07 08:34:54 havasi Exp $
  *
  */
 
@@ -134,7 +134,8 @@ static int jffs2_prepare_write (struct file *filp, struct page *pg,
 		D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
 			  (unsigned int)inode->i_size, pageofs));
 
-		ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL);
+		ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len,
+					ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 		if (ret)
 			return ret;
 
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index c99451a..c15c302 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: fs.c,v 1.64 2005/09/01 08:42:31 havasi Exp $
+ * $Id: fs.c,v 1.65 2005/09/07 08:34:54 havasi Exp $
  *
  */
 
@@ -74,7 +74,8 @@ static int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
 		return -ENOMEM;
 	}
 		
-	ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &phys_ofs, &alloclen, ALLOC_NORMAL);
+	ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &phys_ofs, &alloclen,
+				ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 	if (ret) {
 		jffs2_free_raw_inode(ri);
 		if (S_ISLNK(inode->i_mode & S_IFMT))
diff --git a/fs/jffs2/gc.c b/fs/jffs2/gc.c
index def9715..ee54cdc 100644
--- a/fs/jffs2/gc.c
+++ b/fs/jffs2/gc.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: gc.c,v 1.153 2005/08/17 13:46:22 dedekind Exp $
+ * $Id: gc.c,v 1.154 2005/09/07 08:34:54 havasi Exp $
  *
  */
 
@@ -513,8 +513,11 @@ static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
 	/* Ask for a small amount of space (or the totlen if smaller) because we
 	   don't want to force wastage of the end of a block if splitting would
 	   work. */
-	ret = jffs2_reserve_space_gc(c, min_t(uint32_t, sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN, 
-					      rawlen), &phys_ofs, &alloclen);
+	ret = jffs2_reserve_space_gc(c, min_t(uint32_t, sizeof(struct jffs2_raw_inode) +
+				JFFS2_MIN_DATA_LEN, rawlen), &phys_ofs, &alloclen, rawlen);
+				/* this is not the exact summary size of it,
+					it is only an upper estimation */
+
 	if (ret)
 		return ret;
 
@@ -622,7 +625,9 @@ static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
 			jffs2_dbg_acct_sanity_check(c,jeb);
 			jffs2_dbg_acct_paranoia_check(c, jeb);
 
-			ret = jffs2_reserve_space_gc(c, rawlen, &phys_ofs, &dummy);
+			ret = jffs2_reserve_space_gc(c, rawlen, &phys_ofs, &dummy, rawlen);
+						/* this is not the exact summary size of it,
+							it is only an upper estimation */
 
 			if (!ret) {
 				D1(printk(KERN_DEBUG "Allocated space at 0x%08x to retry failed write.\n", phys_ofs));
@@ -701,7 +706,8 @@ static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_
 
 	}
 	
-	ret = jffs2_reserve_space_gc(c, sizeof(ri) + mdatalen, &phys_ofs, &alloclen);
+	ret = jffs2_reserve_space_gc(c, sizeof(ri) + mdatalen, &phys_ofs, &alloclen,
+				JFFS2_SUMMARY_INODE_SIZE);
 	if (ret) {
 		printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_metadata failed: %d\n",
 		       sizeof(ri)+ mdatalen, ret);
@@ -781,7 +787,8 @@ static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_er
 	rd.node_crc = cpu_to_je32(crc32(0, &rd, sizeof(rd)-8));
 	rd.name_crc = cpu_to_je32(crc32(0, fd->name, rd.nsize));
 	
-	ret = jffs2_reserve_space_gc(c, sizeof(rd)+rd.nsize, &phys_ofs, &alloclen);
+	ret = jffs2_reserve_space_gc(c, sizeof(rd)+rd.nsize, &phys_ofs, &alloclen,
+				JFFS2_SUMMARY_DIRENT_SIZE(rd.nsize));
 	if (ret) {
 		printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_dirent failed: %d\n",
 		       sizeof(rd)+rd.nsize, ret);
@@ -994,7 +1001,8 @@ static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eras
 	ri.data_crc = cpu_to_je32(0);
 	ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
 
-	ret = jffs2_reserve_space_gc(c, sizeof(ri), &phys_ofs, &alloclen);
+	ret = jffs2_reserve_space_gc(c, sizeof(ri), &phys_ofs, &alloclen,
+				JFFS2_SUMMARY_INODE_SIZE);
 	if (ret) {
 		printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_hole failed: %d\n",
 		       sizeof(ri), ret);
@@ -1219,7 +1227,8 @@ static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_era
 		uint32_t cdatalen;
 		uint16_t comprtype = JFFS2_COMPR_NONE;
 
-		ret = jffs2_reserve_space_gc(c, sizeof(ri) + JFFS2_MIN_DATA_LEN, &phys_ofs, &alloclen);
+		ret = jffs2_reserve_space_gc(c, sizeof(ri) + JFFS2_MIN_DATA_LEN, &phys_ofs,
+					&alloclen, JFFS2_SUMMARY_INODE_SIZE);
 
 		if (ret) {
 			printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_dnode failed: %d\n",
@@ -1276,4 +1285,3 @@ static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_era
 	jffs2_gc_release_page(c, pg_ptr, &pg);
 	return ret;
 }
-
diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h
index 1533af8..1222372 100644
--- a/fs/jffs2/nodelist.h
+++ b/fs/jffs2/nodelist.h
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodelist.h,v 1.139 2005/08/31 13:51:00 havasi Exp $
+ * $Id: nodelist.h,v 1.140 2005/09/07 08:34:54 havasi Exp $
  *
  */
 
@@ -20,6 +20,7 @@
 #include <linux/jffs2.h>
 #include <linux/jffs2_fs_sb.h>
 #include <linux/jffs2_fs_i.h>
+#include "summary.h"
 
 #ifdef __ECOS
 #include "os-ecos.h"
@@ -326,8 +327,10 @@ int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode
 
 /* nodemgmt.c */
 int jffs2_thread_should_wake(struct jffs2_sb_info *c);
-int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs, uint32_t *len, int prio);
-int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs, uint32_t *len);
+int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
+			uint32_t *len, int prio, uint32_t sumsize);
+int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
+			uint32_t *len, uint32_t sumsize);
 int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *new);
 void jffs2_complete_reservation(struct jffs2_sb_info *c);
 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
@@ -386,6 +389,10 @@ char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
 /* scan.c */
 int jffs2_scan_medium(struct jffs2_sb_info *c);
 void jffs2_rotate_lists(struct jffs2_sb_info *c);
+int jffs2_fill_scan_buf(struct jffs2_sb_info *c, void *buf,
+				uint32_t ofs, uint32_t len);
+struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
+int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 
 /* build.c */
 int jffs2_do_mount_fs(struct jffs2_sb_info *c);
diff --git a/fs/jffs2/nodemgmt.c b/fs/jffs2/nodemgmt.c
index fe7e70a..208b2bd 100644
--- a/fs/jffs2/nodemgmt.c
+++ b/fs/jffs2/nodemgmt.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodemgmt.c,v 1.124 2005/07/20 15:32:28 dedekind Exp $
+ * $Id: nodemgmt.c,v 1.125 2005/09/07 08:34:54 havasi Exp $
  *
  */
 
@@ -17,6 +17,7 @@
 #include <linux/compiler.h>
 #include <linux/sched.h> /* For cond_resched() */
 #include "nodelist.h"
+#include "debug.h"
 
 /**
  *	jffs2_reserve_space - request physical space to write nodes to flash
@@ -38,9 +39,11 @@
  *	for the requested allocation.
  */
 
-static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize, uint32_t *ofs, uint32_t *len);
+static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize,
+					uint32_t *ofs, uint32_t *len, uint32_t sumsize);
 
-int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs, uint32_t *len, int prio)
+int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
+			uint32_t *len, int prio, uint32_t sumsize)
 {
 	int ret = -EAGAIN;
 	int blocksneeded = c->resv_blocks_write;
@@ -129,7 +132,7 @@ int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs
 			spin_lock(&c->erase_completion_lock);
 		}
 
-		ret = jffs2_do_reserve_space(c, minsize, ofs, len);
+		ret = jffs2_do_reserve_space(c, minsize, ofs, len, sumsize);
 		if (ret) {
 			D1(printk(KERN_DEBUG "jffs2_reserve_space: ret is %d\n", ret));
 		}
@@ -140,7 +143,8 @@ int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs
 	return ret;
 }
 
-int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs, uint32_t *len)
+int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
+			uint32_t *len, uint32_t sumsize)
 {
 	int ret = -EAGAIN;
 	minsize = PAD(minsize);
@@ -149,7 +153,7 @@ int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *
 
 	spin_lock(&c->erase_completion_lock);
 	while(ret == -EAGAIN) {
-		ret = jffs2_do_reserve_space(c, minsize, ofs, len);
+		ret = jffs2_do_reserve_space(c, minsize, ofs, len, sumsize);
 		if (ret) {
 		        D1(printk(KERN_DEBUG "jffs2_reserve_space_gc: looping, ret is %d\n", ret));
 		}
@@ -158,105 +162,183 @@ int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *
 	return ret;
 }
 
-/* Called with alloc sem _and_ erase_completion_lock */
-static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize, uint32_t *ofs, uint32_t *len)
+
+/* Classify nextblock (clean, dirty of verydirty) and force to select an other one */
+
+static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
 {
-	struct jffs2_eraseblock *jeb = c->nextblock;
+
+	/* Check, if we have a dirty block now, or if it was dirty already */
+	if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) {
+		c->dirty_size += jeb->wasted_size;
+		c->wasted_size -= jeb->wasted_size;
+		jeb->dirty_size += jeb->wasted_size;
+		jeb->wasted_size = 0;
+		if (VERYDIRTY(c, jeb->dirty_size)) {
+			D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to very_dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
+			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
+			list_add_tail(&jeb->list, &c->very_dirty_list);
+		} else {
+			D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
+			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
+			list_add_tail(&jeb->list, &c->dirty_list);
+		}
+	} else { 
+		D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
+		  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
+		list_add_tail(&jeb->list, &c->clean_list);
+	}
+	c->nextblock = NULL;
+
+}
+
+/* Select a new jeb for nextblock */
+
+static int jffs2_find_nextblock(struct jffs2_sb_info *c)
+{
+	struct list_head *next;
 	
- restart:
-	if (jeb && minsize > jeb->free_size) {
-		/* Skip the end of this block and file it as having some dirty space */
-		/* If there's a pending write to it, flush now */
-		if (jffs2_wbuf_dirty(c)) {
+	/* Take the next block off the 'free' list */
+
+	if (list_empty(&c->free_list)) {
+
+		if (!c->nr_erasing_blocks &&
+			!list_empty(&c->erasable_list)) {
+			struct jffs2_eraseblock *ejeb;
+
+			ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list);
+			list_del(&ejeb->list);
+			list_add_tail(&ejeb->list, &c->erase_pending_list);
+			c->nr_erasing_blocks++;
+			jffs2_erase_pending_trigger(c);
+			D1(printk(KERN_DEBUG "jffs2_find_nextblock: Triggering erase of erasable block at 0x%08x\n",
+				  ejeb->offset));
+		}
+
+		if (!c->nr_erasing_blocks &&
+			!list_empty(&c->erasable_pending_wbuf_list)) {
+			D1(printk(KERN_DEBUG "jffs2_find_nextblock: Flushing write buffer\n"));
+			/* c->nextblock is NULL, no update to c->nextblock allowed */
 			spin_unlock(&c->erase_completion_lock);
-			D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Flushing write buffer\n"));			    
 			jffs2_flush_wbuf_pad(c);
 			spin_lock(&c->erase_completion_lock);
-			jeb = c->nextblock;
-			goto restart;
+			/* Have another go. It'll be on the erasable_list now */
+			return -EAGAIN;
 		}
-		c->wasted_size += jeb->free_size;
-		c->free_size -= jeb->free_size;
-		jeb->wasted_size += jeb->free_size;
-		jeb->free_size = 0;
-		
-		/* Check, if we have a dirty block now, or if it was dirty already */
-		if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) {
-			c->dirty_size += jeb->wasted_size;
-			c->wasted_size -= jeb->wasted_size;
-			jeb->dirty_size += jeb->wasted_size;
-			jeb->wasted_size = 0;
-			if (VERYDIRTY(c, jeb->dirty_size)) {
-				D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to very_dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
-				  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
-				list_add_tail(&jeb->list, &c->very_dirty_list);
-			} else {
-				D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
-				  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
-				list_add_tail(&jeb->list, &c->dirty_list);
-			}
-		} else { 
-			D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
-			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
-			list_add_tail(&jeb->list, &c->clean_list);
+
+		if (!c->nr_erasing_blocks) {
+			/* Ouch. We're in GC, or we wouldn't have got here.
+			   And there's no space left. At all. */
+			printk(KERN_CRIT "Argh. No free space left for GC. nr_erasing_blocks is %d. nr_free_blocks is %d. (erasableempty: %s, erasingempty: %s, erasependingempty: %s)\n", 
+				   c->nr_erasing_blocks, c->nr_free_blocks, list_empty(&c->erasable_list)?"yes":"no", 
+				   list_empty(&c->erasing_list)?"yes":"no", list_empty(&c->erase_pending_list)?"yes":"no");
+			return -ENOSPC;
 		}
-		c->nextblock = jeb = NULL;
+
+		spin_unlock(&c->erase_completion_lock);
+		/* Don't wait for it; just erase one right now */
+		jffs2_erase_pending_blocks(c, 1);
+		spin_lock(&c->erase_completion_lock);
+
+		/* An erase may have failed, decreasing the
+		   amount of free space available. So we must
+		   restart from the beginning */
+		return -EAGAIN;
 	}
+
+	next = c->free_list.next;
+	list_del(next);
+	c->nextblock = list_entry(next, struct jffs2_eraseblock, list);
+	c->nr_free_blocks--;
 	
-	if (!jeb) {
-		struct list_head *next;
-		/* Take the next block off the 'free' list */
+	jffs2_sum_reset_collected(c->summary); /* reset collected summary */
 
-		if (list_empty(&c->free_list)) {
+	D1(printk(KERN_DEBUG "jffs2_find_nextblock(): new nextblock = 0x%08x\n", c->nextblock->offset));
 
-			if (!c->nr_erasing_blocks && 
-			    !list_empty(&c->erasable_list)) {
-				struct jffs2_eraseblock *ejeb;
+	return 0;
+}
 
-				ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list);
-				list_del(&ejeb->list);
-				list_add_tail(&ejeb->list, &c->erase_pending_list);
-				c->nr_erasing_blocks++;
-				jffs2_erase_pending_trigger(c);
-				D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Triggering erase of erasable block at 0x%08x\n",
-					  ejeb->offset));
+/* Called with alloc sem _and_ erase_completion_lock */
+static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs, uint32_t *len, uint32_t sumsize)
+{
+	struct jffs2_eraseblock *jeb = c->nextblock;
+	uint32_t reserved_size; 			/* for summary information at the end of the jeb */
+	int ret;
+
+ restart:
+	reserved_size = 0;
+
+	if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) {
+							/* NOSUM_SIZE means not to generate summary */
+
+		if (jeb) {
+			reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
+			JFFS2_DBG_SUMMARY("minsize=%d , jeb->free=%d ,"
+						"summary->size=%d , sumsize=%d\n",
+						minsize, jeb->free_size,
+						c->summary->sum_size, sumsize);
+		}
+
+		/* Is there enough space for writing out the current node, or we have to
+		   write out summary information now, close this jeb and select new nextblock? */
+		if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize +
+					JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) {
+
+			/* Has summary been disabled for this jeb? */
+			if (jffs2_sum_is_disabled(c->summary)) {
+				sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
+				goto restart;
 			}
 
-			if (!c->nr_erasing_blocks && 
-			    !list_empty(&c->erasable_pending_wbuf_list)) {
-				D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Flushing write buffer\n"));
-				/* c->nextblock is NULL, no update to c->nextblock allowed */			    
+			/* Writing out the collected summary information */
+			JFFS2_DBG_SUMMARY("generating summary for 0x%08x.\n", jeb->offset);
+			ret = jffs2_sum_write_sumnode(c);
+
+			if (ret)
+				return ret;
+
+			if (jffs2_sum_is_disabled(c->summary)) {
+				/* jffs2_write_sumnode() couldn't write out the summary information
+				   diabling summary for this jeb and free the collected information
+				 */
+				sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
+				goto restart;
+			}
+
+			jffs2_close_nextblock(c, jeb);
+			jeb = NULL;
+		}
+	} else {
+		if (jeb && minsize > jeb->free_size) {
+			/* Skip the end of this block and file it as having some dirty space */
+			/* If there's a pending write to it, flush now */
+
+			if (jffs2_wbuf_dirty(c)) {
 				spin_unlock(&c->erase_completion_lock);
+				D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Flushing write buffer\n"));
 				jffs2_flush_wbuf_pad(c);
 				spin_lock(&c->erase_completion_lock);
-				/* Have another go. It'll be on the erasable_list now */
-				return -EAGAIN;
-			}
-
-			if (!c->nr_erasing_blocks) {
-				/* Ouch. We're in GC, or we wouldn't have got here.
-				   And there's no space left. At all. */
-				printk(KERN_CRIT "Argh. No free space left for GC. nr_erasing_blocks is %d. nr_free_blocks is %d. (erasableempty: %s, erasingempty: %s, erasependingempty: %s)\n", 
-				       c->nr_erasing_blocks, c->nr_free_blocks, list_empty(&c->erasable_list)?"yes":"no", 
-				       list_empty(&c->erasing_list)?"yes":"no", list_empty(&c->erase_pending_list)?"yes":"no");
-				return -ENOSPC;
+				jeb = c->nextblock;
+				goto restart;
 			}
 
-			spin_unlock(&c->erase_completion_lock);
-			/* Don't wait for it; just erase one right now */
-			jffs2_erase_pending_blocks(c, 1);
-			spin_lock(&c->erase_completion_lock);
+			c->wasted_size += jeb->free_size;
+			c->free_size -= jeb->free_size;
+			jeb->wasted_size += jeb->free_size;
+			jeb->free_size = 0;
 
-			/* An erase may have failed, decreasing the
-			   amount of free space available. So we must
-			   restart from the beginning */
-			return -EAGAIN;
+			jffs2_close_nextblock(c, jeb);
+			jeb = NULL;
 		}
+	}
+
+	if (!jeb) {
+
+		ret = jffs2_find_nextblock(c);
+		if (ret)
+			return ret;
 
-		next = c->free_list.next;
-		list_del(next);
-		c->nextblock = jeb = list_entry(next, struct jffs2_eraseblock, list);
-		c->nr_free_blocks--;
+		jeb = c->nextblock;
 
 		if (jeb->free_size != c->sector_size - c->cleanmarker_size) {
 			printk(KERN_WARNING "Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n", jeb->offset, jeb->free_size);
@@ -266,7 +348,7 @@ static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize, ui
 	/* OK, jeb (==c->nextblock) is now pointing at a block which definitely has
 	   enough space */
 	*ofs = jeb->offset + (c->sector_size - jeb->free_size);
-	*len = jeb->free_size;
+	*len = jeb->free_size - reserved_size;
 
 	if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size &&
 	    !jeb->first_node->next_in_ino) {
diff --git a/fs/jffs2/os-linux.h b/fs/jffs2/os-linux.h
index c3c1619..e026888 100644
--- a/fs/jffs2/os-linux.h
+++ b/fs/jffs2/os-linux.h
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: os-linux.h,v 1.60 2005/08/06 04:51:30 nico Exp $
+ * $Id: os-linux.h,v 1.61 2005/09/07 08:34:54 havasi Exp $
  *
  */
 
@@ -67,12 +67,18 @@ static inline void jffs2_init_inode_info(struct jffs2_inode_info *f)
 
 #ifndef CONFIG_JFFS2_FS_WRITEBUFFER
 #define SECTOR_ADDR(x) ( ((unsigned long)(x) & ~(c->sector_size-1)) )
+
+#ifdef CONFIG_JFFS2_SUMMARY
+#define jffs2_can_mark_obsolete(c) (0)
+#else
 #define jffs2_can_mark_obsolete(c) (1)
+#endif
+
 #define jffs2_is_writebuffered(c) (0)
 #define jffs2_cleanmarker_oob(c) (0)
 #define jffs2_write_nand_cleanmarker(c,jeb) (-EIO)
 
-#define jffs2_flash_write(c, ofs, len, retlen, buf) ((c)->mtd->write((c)->mtd, ofs, len, retlen, buf))
+#define jffs2_flash_write(c, ofs, len, retlen, buf) jffs2_flash_direct_write(c, ofs, len, retlen, buf)
 #define jffs2_flash_read(c, ofs, len, retlen, buf) ((c)->mtd->read((c)->mtd, ofs, len, retlen, buf))
 #define jffs2_flush_wbuf_pad(c) ({ (void)(c), 0; })
 #define jffs2_flush_wbuf_gc(c, i) ({ (void)(c), (void) i, 0; })
@@ -97,9 +103,15 @@ static inline void jffs2_init_inode_info(struct jffs2_inode_info *f)
 
 #define jffs2_is_writebuffered(c) (c->wbuf != NULL)
 #define SECTOR_ADDR(x) ( ((unsigned long)(x) / (unsigned long)(c->sector_size)) * c->sector_size )
+
+#ifdef CONFIG_JFFS2_SUMMARY
+#define jffs2_can_mark_obsolete(c) (0)
+#else
 #define jffs2_can_mark_obsolete(c) \
   ((c->mtd->type == MTD_NORFLASH && !(c->mtd->flags & (MTD_ECC|MTD_PROGRAM_REGIONS))) || \
    c->mtd->type == MTD_RAM)
+#endif
+
 #define jffs2_cleanmarker_oob(c) (c->mtd->type == MTD_NANDFLASH)
 
 #define jffs2_flash_write_oob(c, ofs, len, retlen, buf) ((c)->mtd->write_oob((c)->mtd, ofs, len, retlen, buf))
@@ -192,7 +204,8 @@ void jffs2_flash_cleanup(struct jffs2_sb_info *c);
 /* writev.c */
 int jffs2_flash_direct_writev(struct jffs2_sb_info *c, const struct kvec *vecs, 
 		       unsigned long count, loff_t to, size_t *retlen);
-
+int jffs2_flash_direct_write(struct jffs2_sb_info *c, loff_t ofs, size_t len,
+			size_t *retlen, const u_char *buf);
 
 #endif /* __JFFS2_OS_LINUX_H__ */
 
diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
index fcd6314..4e60ba8 100644
--- a/fs/jffs2/scan.c
+++ b/fs/jffs2/scan.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: scan.c,v 1.121 2005/07/20 15:32:28 dedekind Exp $
+ * $Id: scan.c,v 1.122 2005/09/07 08:34:54 havasi Exp $
  *
  */
 #include <linux/kernel.h>
@@ -18,22 +18,11 @@
 #include <linux/crc32.h>
 #include <linux/compiler.h>
 #include "nodelist.h"
+#include "summary.h"
+#include "debug.h"
 
 #define DEFAULT_EMPTY_SCAN_SIZE 1024
 
-#define DIRTY_SPACE(x) do { typeof(x) _x = (x); \
-		c->free_size -= _x; c->dirty_size += _x; \
-		jeb->free_size -= _x ; jeb->dirty_size += _x; \
-		}while(0)
-#define USED_SPACE(x) do { typeof(x) _x = (x); \
-		c->free_size -= _x; c->used_size += _x; \
-		jeb->free_size -= _x ; jeb->used_size += _x; \
-		}while(0)
-#define UNCHECKED_SPACE(x) do { typeof(x) _x = (x); \
-		c->free_size -= _x; c->unchecked_size += _x; \
-		jeb->free_size -= _x ; jeb->unchecked_size += _x; \
-		}while(0)
-
 #define noisy_printk(noise, args...) do { \
 	if (*(noise)) { \
 		printk(KERN_NOTICE args); \
@@ -47,23 +36,16 @@
 static uint32_t pseudo_random;
 
 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
-				  unsigned char *buf, uint32_t buf_size);
+				  unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s);
 
 /* These helper functions _must_ increase ofs and also do the dirty/used space accounting. 
  * Returning an error will abort the mount - bad checksums etc. should just mark the space
  * as dirty.
  */
 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 
-				 struct jffs2_raw_inode *ri, uint32_t ofs);
+				 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s);
 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
-				 struct jffs2_raw_dirent *rd, uint32_t ofs);
-
-#define BLK_STATE_ALLFF		0
-#define BLK_STATE_CLEAN		1
-#define BLK_STATE_PARTDIRTY	2
-#define BLK_STATE_CLEANMARKER	3
-#define BLK_STATE_ALLDIRTY	4
-#define BLK_STATE_BADBLOCK	5
+				 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s);
 
 static inline int min_free(struct jffs2_sb_info *c)
 {
@@ -89,6 +71,7 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 	uint32_t empty_blocks = 0, bad_blocks = 0;
 	unsigned char *flashbuf = NULL;
 	uint32_t buf_size = 0;
+	struct jffs2_summary *s = NULL; /* summary info collected by the scan process */
 #ifndef __ECOS
 	size_t pointlen;
 
@@ -122,10 +105,23 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 			return -ENOMEM;
 	}
 
+	if (jffs2_sum_active()) {
+		s = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL);
+		if (!s) {
+			JFFS2_WARNING("Can't allocate memory for summary\n");
+			return -ENOMEM;
+		}
+		memset(s, 0, sizeof(struct jffs2_summary));
+	}
+
 	for (i=0; i<c->nr_blocks; i++) {
 		struct jffs2_eraseblock *jeb = &c->blocks[i];
 
-		ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), buf_size);
+		/* reset summary info for next eraseblock scan */
+		jffs2_sum_reset_collected(s);
+
+		ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset),
+						buf_size, s);
 
 		if (ret < 0)
 			goto out;
@@ -162,18 +158,18 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 			break;
 
 		case BLK_STATE_CLEAN:
-                        /* Full (or almost full) of clean data. Clean list */
-                        list_add(&jeb->list, &c->clean_list);
+			/* Full (or almost full) of clean data. Clean list */
+			list_add(&jeb->list, &c->clean_list);
 			break;
 
 		case BLK_STATE_PARTDIRTY:
-                        /* Some data, but not full. Dirty list. */
-                        /* We want to remember the block with most free space
-                           and stick it in the 'nextblock' position to start writing to it. */
-                        if (jeb->free_size > min_free(c) && 
-			    (!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
-                                /* Better candidate for the next writes to go to */
-                                if (c->nextblock) {
+			/* Some data, but not full. Dirty list. */
+			/* We want to remember the block with most free space
+			and stick it in the 'nextblock' position to start writing to it. */
+			if (jeb->free_size > min_free(c) &&
+					(!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
+				/* Better candidate for the next writes to go to */
+				if (c->nextblock) {
 					c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
 					c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
 					c->free_size -= c->nextblock->free_size;
@@ -184,9 +180,14 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 					} else {
 						list_add(&c->nextblock->list, &c->dirty_list);
 					}
+					/* deleting summary information of the old nextblock */
+					jffs2_sum_reset_collected(c->summary);
 				}
-                                c->nextblock = jeb;
-                        } else {
+				/* update collected summary infromation for the current nextblock */
+				jffs2_sum_move_collected(c, s);
+				D1(printk(KERN_DEBUG "jffs2_scan_medium(): new nextblock = 0x%08x\n", jeb->offset));
+				c->nextblock = jeb;
+			} else {
 				jeb->dirty_size += jeb->free_size + jeb->wasted_size;
 				c->dirty_size += jeb->free_size + jeb->wasted_size;
 				c->free_size -= jeb->free_size;
@@ -197,30 +198,33 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 				} else {
 					list_add(&jeb->list, &c->dirty_list);
 				}
-                        }
+			}
 			break;
 
 		case BLK_STATE_ALLDIRTY:
 			/* Nothing valid - not even a clean marker. Needs erasing. */
-                        /* For now we just put it on the erasing list. We'll start the erases later */
+			/* For now we just put it on the erasing list. We'll start the erases later */
 			D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset));
-                        list_add(&jeb->list, &c->erase_pending_list);
+			list_add(&jeb->list, &c->erase_pending_list);
 			c->nr_erasing_blocks++;
 			break;
-			
+
 		case BLK_STATE_BADBLOCK:
 			D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset));
-                        list_add(&jeb->list, &c->bad_list);
+			list_add(&jeb->list, &c->bad_list);
 			c->bad_size += c->sector_size;
 			c->free_size -= c->sector_size;
 			bad_blocks++;
 			break;
 		default:
 			printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n");
-			BUG();	
+			BUG();
 		}
 	}
-	
+
+	if (jffs2_sum_active() && s)
+		kfree(s);
+
 	/* Nextblock dirty is always seen as wasted, because we cannot recycle it now */
 	if (c->nextblock && (c->nextblock->dirty_size)) {
 		c->nextblock->wasted_size += c->nextblock->dirty_size;
@@ -265,7 +269,7 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 	return ret;
 }
 
-static int jffs2_fill_scan_buf (struct jffs2_sb_info *c, unsigned char *buf,
+int jffs2_fill_scan_buf (struct jffs2_sb_info *c, void *buf,
 				uint32_t ofs, uint32_t len)
 {
 	int ret;
@@ -286,14 +290,36 @@ static int jffs2_fill_scan_buf (struct jffs2_sb_info *c, unsigned char *buf,
 	return 0;
 }
 
+int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
+{
+	if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size
+		&& (!jeb->first_node || !jeb->first_node->next_phys) )
+		return BLK_STATE_CLEANMARKER;
+
+	/* move blocks with max 4 byte dirty space to cleanlist */
+	else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
+		c->dirty_size -= jeb->dirty_size;
+		c->wasted_size += jeb->dirty_size;
+		jeb->wasted_size += jeb->dirty_size;
+		jeb->dirty_size = 0;
+		return BLK_STATE_CLEAN;
+	} else if (jeb->used_size || jeb->unchecked_size)
+		return BLK_STATE_PARTDIRTY;
+	else
+		return BLK_STATE_ALLDIRTY;
+}
+
 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
-				  unsigned char *buf, uint32_t buf_size) {
+				unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
 	struct jffs2_unknown_node *node;
 	struct jffs2_unknown_node crcnode;
+	struct jffs2_sum_marker *sm;
 	uint32_t ofs, prevofs;
 	uint32_t hdr_crc, buf_ofs, buf_len;
 	int err;
 	int noise = 0;
+
+
 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 	int cleanmarkerfound = 0;
 #endif
@@ -319,10 +345,46 @@ static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblo
 		}
 	}
 #endif
+
+	if (jffs2_sum_active()) {
+		sm = kmalloc(sizeof(struct jffs2_sum_marker), GFP_KERNEL);
+		if (!sm) {
+			return -ENOMEM;
+		}
+
+		err = jffs2_fill_scan_buf(c, (unsigned char *) sm, jeb->offset + c->sector_size -
+					sizeof(struct jffs2_sum_marker), sizeof(struct jffs2_sum_marker));
+		if (err) {
+			kfree(sm);
+			return err;
+		}
+
+		if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC ) {
+			err = jffs2_sum_scan_sumnode(c, jeb, je32_to_cpu(sm->offset), &pseudo_random);
+			if (err) {
+				kfree(sm);
+				return err;
+			}
+		}
+
+		kfree(sm);
+
+		ofs = jeb->offset;
+		prevofs = jeb->offset - 1;
+	}
+
 	buf_ofs = jeb->offset;
 
 	if (!buf_size) {
 		buf_len = c->sector_size;
+
+		if (jffs2_sum_active()) {
+			/* must reread because of summary test */
+			err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
+			if (err)
+				return err;
+		}
+
 	} else {
 		buf_len = EMPTY_SCAN_SIZE(c->sector_size);
 		err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
@@ -367,6 +429,8 @@ static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblo
 
 	noise = 10;
 
+	JFFS2_DBG_SUMMARY("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);
+
 scan_more:	
 	while(ofs < jeb->offset + c->sector_size) {
 
@@ -532,7 +596,7 @@ scan_more:
 				buf_ofs = ofs;
 				node = (void *)buf;
 			}
-			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs);
+			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
 			if (err) return err;
 			ofs += PAD(je32_to_cpu(node->totlen));
 			break;
@@ -548,7 +612,7 @@ scan_more:
 				buf_ofs = ofs;
 				node = (void *)buf;
 			}
-			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs);
+			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
 			if (err) return err;
 			ofs += PAD(je32_to_cpu(node->totlen));
 			break;
@@ -582,6 +646,8 @@ scan_more:
 			break;
 
 		case JFFS2_NODETYPE_PADDING:
+			if (jffs2_sum_active())
+				jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
 			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
 			ofs += PAD(je32_to_cpu(node->totlen));
 			break;
@@ -616,6 +682,13 @@ scan_more:
 		}
 	}
 
+	if (jffs2_sum_active()) {
+		if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
+			JFFS2_DBG_SUMMARY("There is not enough space for "
+				"summary information, disabling for this jeb!\n");
+			jffs2_sum_disable_collecting(s);
+		}
+	}
 
 	D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 
 		  jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size));
@@ -628,24 +701,10 @@ scan_more:
 		jeb->wasted_size = 0;
 	}
 
-	if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 
-		&& (!jeb->first_node || !jeb->first_node->next_phys) )
-		return BLK_STATE_CLEANMARKER;
-		
-	/* move blocks with max 4 byte dirty space to cleanlist */	
-	else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
-		c->dirty_size -= jeb->dirty_size;
-		c->wasted_size += jeb->dirty_size; 
-		jeb->wasted_size += jeb->dirty_size;
-		jeb->dirty_size = 0;
-		return BLK_STATE_CLEAN;
-	} else if (jeb->used_size || jeb->unchecked_size)
-		return BLK_STATE_PARTDIRTY;
-	else
-		return BLK_STATE_ALLDIRTY;
+	return jffs2_scan_classify_jeb(c, jeb);
 }
 
-static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
+struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
 {
 	struct jffs2_inode_cache *ic;
 
@@ -672,7 +731,7 @@ static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info
 }
 
 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 
-				 struct jffs2_raw_inode *ri, uint32_t ofs)
+				 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s)
 {
 	struct jffs2_raw_node_ref *raw;
 	struct jffs2_inode_cache *ic;
@@ -739,11 +798,16 @@ static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_erasebloc
 	pseudo_random += je32_to_cpu(ri->version);
 
 	UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen)));
+
+	if (jffs2_sum_active()) {
+		jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset);
+	}
+
 	return 0;
 }
 
 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 
-				  struct jffs2_raw_dirent *rd, uint32_t ofs)
+				  struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s)
 {
 	struct jffs2_raw_node_ref *raw;
 	struct jffs2_full_dirent *fd;
@@ -817,6 +881,10 @@ static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblo
 	USED_SPACE(PAD(je32_to_cpu(rd->totlen)));
 	jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
 
+	if (jffs2_sum_active()) {
+		jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset);
+	}
+
 	return 0;
 }
 
diff --git a/fs/jffs2/summary.c b/fs/jffs2/summary.c
new file mode 100644
index 0000000..cb5dd8f
--- /dev/null
+++ b/fs/jffs2/summary.c
@@ -0,0 +1,729 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2004  Ferenc Havasi <havasi@inf.u-szeged.hu>,
+ *                     Zoltan Sogor <weth@inf.u-szeged.hu>,
+ *                     Patrik Kluba <pajko@halom.u-szeged.hu>,
+ *                     University of Szeged, Hungary
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ * $Id: summary.c,v 1.1 2005/09/07 08:34:54 havasi Exp $
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/mtd/mtd.h>
+#include <linux/pagemap.h>
+#include <linux/crc32.h>
+#include <linux/compiler.h>
+#include <linux/vmalloc.h>
+#include "nodelist.h"
+#include "debug.h"
+
+int jffs2_sum_init(struct jffs2_sb_info *c)
+{
+	c->summary = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL);
+
+	if (!c->summary) {
+		JFFS2_WARNING("Can't allocate memory for summary information!\n");
+		return -ENOMEM;
+	}
+
+	memset(c->summary, 0, sizeof(struct jffs2_summary));
+
+	c->summary->sum_buf = vmalloc(c->sector_size);
+
+	if (!c->summary->sum_buf) {
+		JFFS2_WARNING("Can't allocate buffer for writing out summary information!\n");
+		return -ENOMEM;
+	}
+
+	JFFS2_DBG_SUMMARY("returned succesfully\n");
+
+	return 0;
+}
+
+void jffs2_sum_exit(struct jffs2_sb_info *c)
+{
+	JFFS2_DBG_SUMMARY("called\n");
+
+	jffs2_sum_disable_collecting(c->summary);
+
+	vfree(c->summary->sum_buf);
+	c->summary->sum_buf = NULL;
+
+	kfree(c->summary);
+	c->summary = NULL;
+}
+
+static int jffs2_sum_add_mem(struct jffs2_summary *s, union jffs2_sum_mem *item)
+{
+	if (!s->sum_list_head)
+		s->sum_list_head = (union jffs2_sum_mem *) item;
+	if (s->sum_list_tail)
+		s->sum_list_tail->u.next = (union jffs2_sum_mem *) item;
+	s->sum_list_tail = (union jffs2_sum_mem *) item;
+
+	switch (je16_to_cpu(item->u.nodetype)) {
+		case JFFS2_NODETYPE_INODE:
+			s->sum_size += JFFS2_SUMMARY_INODE_SIZE;
+			s->sum_num++;
+			JFFS2_DBG_SUMMARY("inode (%u) added to summary\n",
+						je32_to_cpu(item->i.inode));
+			break;
+		case JFFS2_NODETYPE_DIRENT:
+			s->sum_size += JFFS2_SUMMARY_DIRENT_SIZE(item->d.nsize);
+			s->sum_num++;
+			JFFS2_DBG_SUMMARY("dirent (%u) added to summary\n",
+						je32_to_cpu(item->d.ino));
+			break;
+		default:
+			JFFS2_WARNING("UNKNOWN node type %u\n", 
+					    je16_to_cpu(item->u.nodetype));
+			return 1;
+	}
+	return 0;
+}
+
+
+/* The following 3 functions are called from scan.c to collect summary info for not closed jeb */
+
+int jffs2_sum_add_padding_mem(struct jffs2_summary *s, uint32_t size)
+{
+	JFFS2_DBG_SUMMARY("called with %u\n", size);
+	s->sum_padded += size;
+	return 0;
+}
+
+int jffs2_sum_add_inode_mem(struct jffs2_summary *s, struct jffs2_raw_inode *ri,
+				uint32_t ofs)
+{
+	struct jffs2_sum_inode_mem *temp = kmalloc(sizeof(struct jffs2_sum_inode_mem), GFP_KERNEL);
+
+	if (!temp)
+		return -ENOMEM;
+
+	temp->nodetype = ri->nodetype;
+	temp->inode = ri->ino;
+	temp->version = ri->version;
+	temp->offset = cpu_to_je32(ofs); /* relative offset from the begining of the jeb */
+	temp->totlen = ri->totlen;
+	temp->next = NULL;
+
+	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
+}
+
+int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *rd,
+				uint32_t ofs)
+{
+	struct jffs2_sum_dirent_mem *temp =
+		kmalloc(sizeof(struct jffs2_sum_dirent_mem) + rd->nsize, GFP_KERNEL);
+
+	if (!temp)
+		return -ENOMEM;
+
+	temp->nodetype = rd->nodetype;
+	temp->totlen = rd->totlen;
+	temp->offset = cpu_to_je32(ofs);	/* relative from the begining of the jeb */
+	temp->pino = rd->pino;
+	temp->version = rd->version;
+	temp->ino = rd->ino;
+	temp->nsize = rd->nsize;
+	temp->type = rd->type;
+	temp->next = NULL;
+
+	memcpy(temp->name, rd->name, rd->nsize);
+
+	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
+}
+
+/* Cleanup every collected summary information */
+
+static void jffs2_sum_clean_collected(struct jffs2_summary *s)
+{
+	union jffs2_sum_mem *temp;
+
+	if (!s->sum_list_head) {
+		JFFS2_DBG_SUMMARY("already empty\n");
+	}
+	while (s->sum_list_head) {
+		temp = s->sum_list_head;
+		s->sum_list_head = s->sum_list_head->u.next;
+		kfree(temp);
+	}
+	s->sum_list_tail = NULL;
+	s->sum_padded = 0;
+	s->sum_num = 0;
+}
+
+void jffs2_sum_reset_collected(struct jffs2_summary *s)
+{
+	JFFS2_DBG_SUMMARY("called\n");
+	jffs2_sum_clean_collected(s);
+	s->sum_size = 0;
+}
+
+void jffs2_sum_disable_collecting(struct jffs2_summary *s)
+{
+	JFFS2_DBG_SUMMARY("called\n");
+	jffs2_sum_clean_collected(s);
+	s->sum_size = JFFS2_SUMMARY_NOSUM_SIZE;
+}
+
+int jffs2_sum_is_disabled(struct jffs2_summary *s) 
+{
+	return (s->sum_size == JFFS2_SUMMARY_NOSUM_SIZE);
+}
+
+/* Move the collected summary information into sb (called from scan.c) */
+
+void jffs2_sum_move_collected(struct jffs2_sb_info *c, struct jffs2_summary *s)
+{
+	JFFS2_DBG_SUMMARY("oldsize=0x%x oldnum=%u => newsize=0x%x newnum=%u\n",
+				c->summary->sum_size, c->summary->sum_num,
+				s->sum_size, s->sum_num);
+
+	c->summary->sum_size = s->sum_size;
+	c->summary->sum_num = s->sum_num;
+	c->summary->sum_padded = s->sum_padded;
+	c->summary->sum_list_head = s->sum_list_head;
+	c->summary->sum_list_tail = s->sum_list_tail;
+
+	s->sum_list_head = s->sum_list_tail = NULL;
+}
+
+/* Called from wbuf.c to collect writed node info */
+
+int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
+				unsigned long count, uint32_t ofs)
+{
+	union jffs2_node_union *node;
+	struct jffs2_eraseblock *jeb;
+
+	node = invecs[0].iov_base;
+	jeb = &c->blocks[ofs / c->sector_size];
+	ofs -= jeb->offset;
+
+	switch (je16_to_cpu(node->u.nodetype)) {
+		case JFFS2_NODETYPE_INODE: {
+			struct jffs2_sum_inode_mem *temp =
+				kmalloc(sizeof(struct jffs2_sum_inode_mem), GFP_KERNEL);
+
+			if (!temp)
+				goto no_mem;
+
+			temp->nodetype = node->i.nodetype;
+			temp->inode = node->i.ino;
+			temp->version = node->i.version;
+			temp->offset = cpu_to_je32(ofs);
+			temp->totlen = node->i.totlen;
+			temp->next = NULL;
+
+			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
+		}
+
+		case JFFS2_NODETYPE_DIRENT: {
+			struct jffs2_sum_dirent_mem *temp =
+				kmalloc(sizeof(struct jffs2_sum_dirent_mem) + node->d.nsize, GFP_KERNEL);
+
+			if (!temp)
+				goto no_mem;
+
+			temp->nodetype = node->d.nodetype;
+			temp->totlen = node->d.totlen;
+			temp->offset = cpu_to_je32(ofs);
+			temp->pino = node->d.pino;
+			temp->version = node->d.version;
+			temp->ino = node->d.ino;
+			temp->nsize = node->d.nsize;
+			temp->type = node->d.type;
+			temp->next = NULL;
+
+			switch (count) {
+				case 1:
+					memcpy(temp->name,node->d.name,node->d.nsize);
+					break;
+
+				case 2:
+					memcpy(temp->name,invecs[1].iov_base,node->d.nsize);
+					break;
+
+				default:
+					BUG();	/* impossible count value */
+					break;
+			}
+
+			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
+		}
+
+		case JFFS2_NODETYPE_PADDING:
+			JFFS2_DBG_SUMMARY("node PADDING\n");
+			c->summary->sum_padded += je32_to_cpu(node->u.totlen);
+			break;
+
+		case JFFS2_NODETYPE_CLEANMARKER:
+			JFFS2_DBG_SUMMARY("node CLEANMARKER\n");
+			break;
+
+		case JFFS2_NODETYPE_SUMMARY:
+			JFFS2_DBG_SUMMARY("node SUMMARY\n");
+			break;
+
+		default:
+			/* If you implement a new node type you should also implement
+			   summary support for it or disable summary.
+			*/
+			BUG();
+			break;
+	}
+
+	return 0;
+
+no_mem:
+	JFFS2_WARNING("MEMORY ALLOCATION ERROR!");
+	return -ENOMEM;
+}
+
+
+/* Process the stored summary information - helper function for jffs2_sum_scan_sumnode() */
+
+static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				struct jffs2_summary_node *summary, uint32_t *pseudo_random)
+{
+	struct jffs2_raw_node_ref *raw;
+	struct jffs2_inode_cache *ic;
+	struct jffs2_full_dirent *fd;
+	void *sp;
+	int i, ino;
+
+	sp = summary->sum;
+
+	for (i=0; i<je32_to_cpu(summary->sum_num); i++) {
+		JFFS2_DBG_SUMMARY("processing summary index %d\n", i);
+
+		switch (je16_to_cpu(((struct jffs2_sum_unknown_flash *)sp)->nodetype)) {
+			case JFFS2_NODETYPE_INODE: {
+				struct jffs2_sum_inode_flash *spi;
+				spi = sp;
+
+				ino = je32_to_cpu(spi->inode);
+
+				JFFS2_DBG_SUMMARY("Inode at 0x%08x\n",
+							jeb->offset + je32_to_cpu(spi->offset));
+
+				raw = jffs2_alloc_raw_node_ref();
+				if (!raw) {
+					JFFS2_NOTICE("allocation of node reference failed\n");
+					kfree(summary);
+					return -ENOMEM;
+				}
+
+				ic = jffs2_scan_make_ino_cache(c, ino);
+				if (!ic) {
+					JFFS2_NOTICE("scan_make_ino_cache failed\n");
+					jffs2_free_raw_node_ref(raw);
+					kfree(summary);
+					return -ENOMEM;
+				}
+
+				raw->flash_offset = (jeb->offset + je32_to_cpu(spi->offset)) | REF_UNCHECKED;
+				raw->__totlen = PAD(je32_to_cpu(spi->totlen));
+				raw->next_phys = NULL;
+				raw->next_in_ino = ic->nodes;
+
+				ic->nodes = raw;
+				if (!jeb->first_node)
+					jeb->first_node = raw;
+				if (jeb->last_node)
+					jeb->last_node->next_phys = raw;
+				jeb->last_node = raw;
+				*pseudo_random += je32_to_cpu(spi->version);
+
+				UNCHECKED_SPACE(PAD(je32_to_cpu(spi->totlen)));
+
+				sp += JFFS2_SUMMARY_INODE_SIZE;
+
+				break;
+			}
+
+			case JFFS2_NODETYPE_DIRENT: {
+				struct jffs2_sum_dirent_flash *spd;
+				spd = sp;
+
+				JFFS2_DBG_SUMMARY("Dirent at 0x%08x\n",
+							jeb->offset + je32_to_cpu(spd->offset));
+
+				fd = jffs2_alloc_full_dirent(spd->nsize+1);
+				if (!fd) {
+					kfree(summary);
+					return -ENOMEM;
+				}
+
+				memcpy(&fd->name, spd->name, spd->nsize);
+				fd->name[spd->nsize] = 0;
+
+				raw = jffs2_alloc_raw_node_ref();
+				if (!raw) {
+					jffs2_free_full_dirent(fd);
+					JFFS2_NOTICE("allocation of node reference failed\n");
+					kfree(summary);
+					return -ENOMEM;
+				}
+
+				ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(spd->pino));
+				if (!ic) {
+					jffs2_free_full_dirent(fd);
+					jffs2_free_raw_node_ref(raw);
+					kfree(summary);
+					return -ENOMEM;
+				}
+
+				raw->__totlen = PAD(je32_to_cpu(spd->totlen));
+				raw->flash_offset = (jeb->offset + je32_to_cpu(spd->offset)) | REF_PRISTINE;
+				raw->next_phys = NULL;
+				raw->next_in_ino = ic->nodes;
+				ic->nodes = raw;
+				if (!jeb->first_node)
+					jeb->first_node = raw;
+				if (jeb->last_node)
+					jeb->last_node->next_phys = raw;
+				jeb->last_node = raw;
+
+				fd->raw = raw;
+				fd->next = NULL;
+				fd->version = je32_to_cpu(spd->version);
+				fd->ino = je32_to_cpu(spd->ino);
+				fd->nhash = full_name_hash(fd->name, spd->nsize);
+				fd->type = spd->type;
+				USED_SPACE(PAD(je32_to_cpu(spd->totlen)));
+				jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
+
+				*pseudo_random += je32_to_cpu(spd->version);
+
+				sp += JFFS2_SUMMARY_DIRENT_SIZE(spd->nsize);
+
+				break;
+			}
+
+			default : {
+				JFFS2_WARNING("Unsupported node type found in summary! Exiting...");
+				kfree(summary);
+				return -EIO;
+			}
+		}
+	}
+
+	kfree(summary);
+	return 0;
+}
+
+/* Process the summary node - called from jffs2_scan_eraseblock() */
+
+int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				uint32_t ofs, uint32_t *pseudo_random)
+{
+	struct jffs2_unknown_node crcnode;
+	struct jffs2_raw_node_ref *cache_ref;
+	struct jffs2_summary_node *summary;
+	int ret, sumsize;
+	uint32_t crc;
+
+	sumsize = c->sector_size - ofs;
+	ofs += jeb->offset;
+
+	JFFS2_DBG_SUMMARY("summary found for 0x%08x at 0x%08x (0x%x bytes)\n",
+				jeb->offset, ofs, sumsize);
+
+	summary = kmalloc(sumsize, GFP_KERNEL);
+
+	if (!summary) {
+		return -ENOMEM;
+	}
+
+	ret = jffs2_fill_scan_buf(c, (unsigned char *)summary, ofs, sumsize);
+
+	if (ret) {
+		kfree(summary);
+		return ret;
+	}
+
+	/* OK, now check for node validity and CRC */
+	crcnode.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	crcnode.nodetype = cpu_to_je16(JFFS2_NODETYPE_SUMMARY);
+	crcnode.totlen = summary->totlen;
+	crc = crc32(0, &crcnode, sizeof(crcnode)-4);
+
+	if (je32_to_cpu(summary->hdr_crc) != crc) {
+		JFFS2_DBG_SUMMARY("Summary node header is corrupt (bad CRC or "
+				"no summary at all)\n");
+		goto crc_err;
+	}
+
+	if (je32_to_cpu(summary->totlen) != sumsize) {
+		JFFS2_DBG_SUMMARY("Summary node is corrupt (wrong erasesize?)\n");
+		goto crc_err;
+	}
+
+	crc = crc32(0, summary, sizeof(struct jffs2_summary_node)-8);
+
+	if (je32_to_cpu(summary->node_crc) != crc) {
+		JFFS2_DBG_SUMMARY("Summary node is corrupt (bad CRC)\n");
+		goto crc_err;
+	}
+
+	crc = crc32(0, summary->sum, sumsize - sizeof(struct jffs2_summary_node));
+
+	if (je32_to_cpu(summary->sum_crc) != crc) {
+		JFFS2_DBG_SUMMARY("Summary node data is corrupt (bad CRC)\n");
+		goto crc_err;
+	}
+
+	if ( je32_to_cpu(summary->cln_mkr) ) {
+
+		JFFS2_DBG_SUMMARY("Summary : CLEANMARKER node \n");
+
+		if (je32_to_cpu(summary->cln_mkr) != c->cleanmarker_size) {
+			JFFS2_DBG_SUMMARY("CLEANMARKER node has totlen 0x%x != normal 0x%x\n",
+				je32_to_cpu(summary->cln_mkr), c->cleanmarker_size);
+			UNCHECKED_SPACE(PAD(je32_to_cpu(summary->cln_mkr)));
+		} else if (jeb->first_node) {
+			JFFS2_DBG_SUMMARY("CLEANMARKER node not first node in block "
+					"(0x%08x)\n", jeb->offset);
+			UNCHECKED_SPACE(PAD(je32_to_cpu(summary->cln_mkr)));
+		} else {
+			struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
+
+			if (!marker_ref) {
+				JFFS2_NOTICE("Failed to allocate node ref for clean marker\n");
+				kfree(summary);
+				return -ENOMEM;
+			}
+
+			marker_ref->next_in_ino = NULL;
+			marker_ref->next_phys = NULL;
+			marker_ref->flash_offset = jeb->offset | REF_NORMAL;
+			marker_ref->__totlen = je32_to_cpu(summary->cln_mkr);
+			jeb->first_node = jeb->last_node = marker_ref;
+
+			USED_SPACE( PAD(je32_to_cpu(summary->cln_mkr)) );
+		}
+	}
+
+	if (je32_to_cpu(summary->padded)) {
+		DIRTY_SPACE(je32_to_cpu(summary->padded));
+	}
+
+	ret = jffs2_sum_process_sum_data(c, jeb, summary, pseudo_random);
+	if (ret)
+		return ret;
+
+	/* for PARANOIA_CHECK */
+	cache_ref = jffs2_alloc_raw_node_ref();
+
+	if (!cache_ref) {
+		JFFS2_NOTICE("Failed to allocate node ref for cache\n");
+		return -ENOMEM;
+	}
+
+	cache_ref->next_in_ino = NULL;
+	cache_ref->next_phys = NULL;
+	cache_ref->flash_offset = ofs | REF_NORMAL;
+	cache_ref->__totlen = sumsize;
+
+	if (!jeb->first_node)
+		jeb->first_node = cache_ref;
+	if (jeb->last_node)
+		jeb->last_node->next_phys = cache_ref;
+	jeb->last_node = cache_ref;
+
+	USED_SPACE(sumsize);
+
+	jeb->wasted_size += jeb->free_size;
+	c->wasted_size += jeb->free_size;
+	c->free_size -= jeb->free_size;
+	jeb->free_size = 0;
+
+	return jffs2_scan_classify_jeb(c, jeb);
+
+crc_err:
+	JFFS2_WARNING("Summary node crc error, skipping summary information.\n");
+
+	return 0;
+}
+
+/* Write summary data to flash - helper function for jffs2_sum_write_sumnode() */
+
+static int jffs2_sum_write_data(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+					uint32_t infosize, uint32_t datasize, int padsize)
+{
+	struct jffs2_summary_node isum;
+	union jffs2_sum_mem *temp;
+	struct jffs2_sum_marker *sm;
+	struct kvec vecs[2];
+	void *wpage;
+	int ret;
+	size_t retlen;
+
+	memset(c->summary->sum_buf, 0xff, datasize);
+	memset(&isum, 0, sizeof(isum));
+
+	isum.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	isum.nodetype = cpu_to_je16(JFFS2_NODETYPE_SUMMARY);
+	isum.totlen = cpu_to_je32(infosize);
+	isum.hdr_crc = cpu_to_je32(crc32(0, &isum, sizeof(struct jffs2_unknown_node) - 4));
+	isum.padded = cpu_to_je32(c->summary->sum_padded);
+	isum.cln_mkr = cpu_to_je32(c->cleanmarker_size);
+	isum.sum_num = cpu_to_je32(c->summary->sum_num);
+	wpage = c->summary->sum_buf;
+
+	while (c->summary->sum_num) {
+
+		switch (je16_to_cpu(c->summary->sum_list_head->u.nodetype)) {
+			case JFFS2_NODETYPE_INODE: {
+				struct jffs2_sum_inode_flash *sino_ptr = wpage;
+
+				sino_ptr->nodetype = c->summary->sum_list_head->i.nodetype;
+				sino_ptr->inode = c->summary->sum_list_head->i.inode;
+				sino_ptr->version = c->summary->sum_list_head->i.version;
+				sino_ptr->offset = c->summary->sum_list_head->i.offset;
+				sino_ptr->totlen = c->summary->sum_list_head->i.totlen;
+
+				wpage += JFFS2_SUMMARY_INODE_SIZE;
+
+				break;
+			}
+
+			case JFFS2_NODETYPE_DIRENT: {
+				struct jffs2_sum_dirent_flash *sdrnt_ptr = wpage;
+
+				sdrnt_ptr->nodetype = c->summary->sum_list_head->d.nodetype;
+				sdrnt_ptr->totlen = c->summary->sum_list_head->d.totlen;
+				sdrnt_ptr->offset = c->summary->sum_list_head->d.offset;
+				sdrnt_ptr->pino = c->summary->sum_list_head->d.pino;
+				sdrnt_ptr->version = c->summary->sum_list_head->d.version;
+				sdrnt_ptr->ino = c->summary->sum_list_head->d.ino;
+				sdrnt_ptr->nsize = c->summary->sum_list_head->d.nsize;
+				sdrnt_ptr->type = c->summary->sum_list_head->d.type;
+
+				memcpy(sdrnt_ptr->name, c->summary->sum_list_head->d.name, 
+							c->summary->sum_list_head->d.nsize);
+
+				wpage += JFFS2_SUMMARY_DIRENT_SIZE(c->summary->sum_list_head->d.nsize);
+
+				break;
+			}
+
+			default : {
+				BUG();	/* unknown node in summary information */
+			}
+		}
+
+		temp = c->summary->sum_list_head;
+		c->summary->sum_list_head = c->summary->sum_list_head->u.next;
+		kfree(temp);
+
+		c->summary->sum_num--;
+	}
+
+	jffs2_sum_reset_collected(c->summary);
+
+	wpage += padsize;
+
+	sm = wpage;
+	sm->offset = cpu_to_je32(c->sector_size - jeb->free_size);
+	sm->magic = cpu_to_je32(JFFS2_SUM_MAGIC);
+
+	isum.sum_crc = cpu_to_je32(crc32(0, c->summary->sum_buf, datasize));
+	isum.node_crc = cpu_to_je32(crc32(0, &isum, sizeof(isum) - 8));
+
+	vecs[0].iov_base = &isum;
+	vecs[0].iov_len = sizeof(isum);
+	vecs[1].iov_base = c->summary->sum_buf;
+	vecs[1].iov_len = datasize;
+
+	JFFS2_DBG_SUMMARY("JFFS2: writing out data to flash to pos : 0x%08x\n",
+			jeb->offset + c->sector_size - jeb->free_size);
+
+	spin_unlock(&c->erase_completion_lock);
+	ret = jffs2_flash_writev(c, vecs, 2, jeb->offset + c->sector_size -
+				jeb->free_size, &retlen, 0);
+	spin_lock(&c->erase_completion_lock);
+
+
+	if (ret || (retlen != infosize)) {
+		JFFS2_WARNING("Write of %zd bytes at 0x%08x failed. returned %d, retlen %zd\n",
+			infosize, jeb->offset + c->sector_size - jeb->free_size, ret, retlen);
+
+		c->summary->sum_size = JFFS2_SUMMARY_NOSUM_SIZE;
+		WASTED_SPACE(infosize);
+
+		return 1;
+	}
+
+	return 0;
+}
+
+/* Write out summary information - called from jffs2_do_reserve_space */
+
+int jffs2_sum_write_sumnode(struct jffs2_sb_info *c)
+{
+	struct jffs2_raw_node_ref *summary_ref;
+	int datasize, infosize, padsize, ret;
+	struct jffs2_eraseblock *jeb;
+
+	JFFS2_DBG_SUMMARY("called\n");
+
+	jeb = c->nextblock;
+
+	if (!c->summary->sum_num || !c->summary->sum_list_head) {
+		JFFS2_WARNING("Empty summary info!!!\n");
+		BUG();
+	}
+
+	datasize = c->summary->sum_size + sizeof(struct jffs2_sum_marker);
+	infosize = sizeof(struct jffs2_summary_node) + datasize;
+	padsize = jeb->free_size - infosize;
+	infosize += padsize; 
+	datasize += padsize;
+
+	/* Is there enough space for summary? */
+	if (padsize < 0) {
+		/* don't try to write out summary for this jeb */
+		jffs2_sum_disable_collecting(c->summary);
+
+		JFFS2_WARNING("Not enough space for summary, padsize = %d\n", padsize);
+		return 0;
+	}
+
+	ret = jffs2_sum_write_data(c, jeb, infosize, datasize, padsize);
+	if (ret)
+		return 0; /* can't write out summary, block is marked as NOSUM_SIZE */
+
+	/* for ACCT_PARANOIA_CHECK */
+	spin_unlock(&c->erase_completion_lock);
+	summary_ref = jffs2_alloc_raw_node_ref();
+	spin_lock(&c->erase_completion_lock);
+
+	if (!summary_ref) {
+		JFFS2_NOTICE("Failed to allocate node ref for summary\n");
+		return -ENOMEM;
+	}
+
+	summary_ref->next_in_ino = NULL;
+	summary_ref->next_phys = NULL;
+	summary_ref->flash_offset = (jeb->offset + c->sector_size - jeb->free_size) | REF_NORMAL;
+	summary_ref->__totlen = infosize;
+
+	if (!jeb->first_node)
+		jeb->first_node = summary_ref;
+	if (jeb->last_node)
+		jeb->last_node->next_phys = summary_ref;
+	jeb->last_node = summary_ref;
+
+	USED_SPACE(infosize);
+
+	return 0;
+}
diff --git a/fs/jffs2/summary.h b/fs/jffs2/summary.h
new file mode 100644
index 0000000..e6b0a69
--- /dev/null
+++ b/fs/jffs2/summary.h
@@ -0,0 +1,183 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2004  Ferenc Havasi <havasi@inf.u-szeged.hu>,
+ *                     Zoltan Sogor <weth@inf.u-szeged.hu>,
+ *                     Patrik Kluba <pajko@halom.u-szeged.hu>,
+ *                     University of Szeged, Hungary
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ * $Id: summary.h,v 1.1 2005/09/07 08:34:54 havasi Exp $
+ *
+ */
+
+#ifndef JFFS2_SUMMARY_H
+#define JFFS2_SUMMARY_H
+
+#include <linux/uio.h>
+#include <linux/jffs2.h>
+
+#define DIRTY_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->dirty_size += _x; \
+		jeb->free_size -= _x ; jeb->dirty_size += _x; \
+		}while(0)
+#define USED_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->used_size += _x; \
+		jeb->free_size -= _x ; jeb->used_size += _x; \
+		}while(0)
+#define WASTED_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->wasted_size += _x; \
+		jeb->free_size -= _x ; jeb->wasted_size += _x; \
+		}while(0)
+#define UNCHECKED_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->unchecked_size += _x; \
+		jeb->free_size -= _x ; jeb->unchecked_size += _x; \
+		}while(0)
+
+#define BLK_STATE_ALLFF		0
+#define BLK_STATE_CLEAN		1
+#define BLK_STATE_PARTDIRTY	2
+#define BLK_STATE_CLEANMARKER	3
+#define BLK_STATE_ALLDIRTY	4
+#define BLK_STATE_BADBLOCK	5
+
+#define JFFS2_SUMMARY_NOSUM_SIZE 0xffffffff
+#define JFFS2_SUMMARY_INODE_SIZE (sizeof(struct jffs2_sum_inode_flash))
+#define JFFS2_SUMMARY_DIRENT_SIZE(x) (sizeof(struct jffs2_sum_dirent_flash) + (x))
+
+/* Summary structures used on flash */
+
+struct jffs2_sum_unknown_flash
+{
+	jint16_t nodetype;	/* node type */
+};
+
+struct jffs2_sum_inode_flash
+{
+	jint16_t nodetype;	/* node type */
+	jint32_t inode;		/* inode number */
+	jint32_t version;	/* inode version */
+	jint32_t offset;	/* offset on jeb */
+	jint32_t totlen; 	/* record length */
+} __attribute__((packed));
+
+struct jffs2_sum_dirent_flash
+{
+	jint16_t nodetype;	/* == JFFS_NODETYPE_DIRENT */
+	jint32_t totlen;	/* record length */
+	jint32_t offset;	/* offset on jeb */
+	jint32_t pino;		/* parent inode */
+	jint32_t version;	/* dirent version */
+	jint32_t ino; 		/* == zero for unlink */
+	uint8_t nsize;		/* dirent name size */
+	uint8_t type;		/* dirent type */
+	uint8_t name[0];	/* dirent name */
+} __attribute__((packed));
+
+union jffs2_sum_flash
+{
+	struct jffs2_sum_unknown_flash u;
+	struct jffs2_sum_inode_flash i;
+	struct jffs2_sum_dirent_flash d;
+};
+
+/* Summary structures used in the memory */
+
+struct jffs2_sum_unknown_mem
+{
+	union jffs2_sum_mem *next;
+	jint16_t nodetype;	/* node type */
+};
+
+struct jffs2_sum_inode_mem
+{
+	union jffs2_sum_mem *next;
+	jint16_t nodetype;	/* node type */
+	jint32_t inode;		/* inode number */
+	jint32_t version;	/* inode version */
+	jint32_t offset;	/* offset on jeb */
+	jint32_t totlen; 	/* record length */
+} __attribute__((packed));
+
+struct jffs2_sum_dirent_mem
+{
+	union jffs2_sum_mem *next;
+	jint16_t nodetype;	/* == JFFS_NODETYPE_DIRENT */
+	jint32_t totlen;	/* record length */
+	jint32_t offset;	/* ofset on jeb */
+	jint32_t pino;		/* parent inode */
+	jint32_t version;	/* dirent version */
+	jint32_t ino; 		/* == zero for unlink */
+	uint8_t nsize;		/* dirent name size */
+	uint8_t type;		/* dirent type */
+	uint8_t name[0];	/* dirent name */
+} __attribute__((packed));
+
+union jffs2_sum_mem
+{
+	struct jffs2_sum_unknown_mem u;
+	struct jffs2_sum_inode_mem i;
+	struct jffs2_sum_dirent_mem d;
+};
+
+/* Summary related information stored in superblock */
+
+struct jffs2_summary
+{
+	uint32_t sum_size;      /* collected summary information for nextblock */
+	uint32_t sum_num;
+	uint32_t sum_padded;
+	union jffs2_sum_mem *sum_list_head;
+	union jffs2_sum_mem *sum_list_tail;
+
+	jint32_t *sum_buf;	/* buffer for writing out summary */
+};
+
+/* Summary marker is stored at the end of every sumarized erase block */
+
+struct jffs2_sum_marker
+{
+	jint32_t offset;	/* offset of the summary node in the jeb */
+	jint32_t magic; 	/* == JFFS2_SUM_MAGIC */
+};
+
+#define JFFS2_SUMMARY_FRAME_SIZE (sizeof(struct jffs2_summary_node) + sizeof(struct jffs2_sum_marker))
+
+#ifdef CONFIG_JFFS2_SUMMARY	/* SUMMARY SUPPORT ENABLED */
+
+#define jffs2_sum_active() (1)
+int jffs2_sum_init(struct jffs2_sb_info *c);
+void jffs2_sum_exit(struct jffs2_sb_info *c);
+void jffs2_sum_disable_collecting(struct jffs2_summary *s);
+int jffs2_sum_is_disabled(struct jffs2_summary *s);
+void jffs2_sum_reset_collected(struct jffs2_summary *s);
+void jffs2_sum_move_collected(struct jffs2_sb_info *c, struct jffs2_summary *s);
+int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
+			unsigned long count,  uint32_t to);
+int jffs2_sum_write_sumnode(struct jffs2_sb_info *c);
+int jffs2_sum_add_padding_mem(struct jffs2_summary *s, uint32_t size);
+int jffs2_sum_add_inode_mem(struct jffs2_summary *s, struct jffs2_raw_inode *ri, uint32_t ofs);
+int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *rd, uint32_t ofs);
+int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+			uint32_t ofs, uint32_t *pseudo_random);
+
+#else				/* SUMMARY DISABLED */
+
+#define jffs2_sum_active() (0)
+#define jffs2_sum_init(a) (0)
+#define jffs2_sum_exit(a)
+#define jffs2_sum_disable_collecting(a)
+#define jffs2_sum_is_disabled(a) (0)
+#define jffs2_sum_reset_collected(a)
+#define jffs2_sum_add_kvec(a,b,c,d) (0)
+#define jffs2_sum_move_collected(a,b)
+#define jffs2_sum_write_sumnode(a) (0)
+#define jffs2_sum_add_padding_mem(a,b)
+#define jffs2_sum_add_inode_mem(a,b,c)
+#define jffs2_sum_add_dirent_mem(a,b,c)
+#define jffs2_sum_scan_sumnode(a,b,c,d) (0)
+
+#endif /* CONFIG_JFFS2_SUMMARY */
+
+#endif /* JFFS2_SUMMARY_H */
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index 58496a0..99028af 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: super.c,v 1.108 2005/08/31 13:51:00 havasi Exp $
+ * $Id: super.c,v 1.109 2005/09/07 08:34:55 havasi Exp $
  *
  */
 
@@ -282,6 +282,9 @@ static void jffs2_put_super (struct super_block *sb)
 	down(&c->alloc_sem);
 	jffs2_flush_wbuf_pad(c);
 	up(&c->alloc_sem);
+
+	jffs2_sum_exit(c);
+
 	jffs2_free_ino_caches(c);
 	jffs2_free_raw_node_refs(c);
 	if (jffs2_blocks_use_vmalloc(c))
@@ -321,6 +324,9 @@ static int __init init_jffs2_fs(void)
 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 	       " (NAND)"
 #endif
+#ifdef CONFIG_JFFS2_SUMMARY
+	       " (SUMMARY) "
+#endif
 	       " (C) 2001-2003 Red Hat, Inc.\n");
 
 	jffs2_inode_cachep = kmem_cache_create("jffs2_i",
diff --git a/fs/jffs2/wbuf.c b/fs/jffs2/wbuf.c
index 8c06d3a..86860db 100644
--- a/fs/jffs2/wbuf.c
+++ b/fs/jffs2/wbuf.c
@@ -9,7 +9,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: wbuf.c,v 1.97 2005/08/06 04:51:30 nico Exp $
+ * $Id: wbuf.c,v 1.98 2005/09/07 08:34:55 havasi Exp $
  *
  */
 
@@ -265,7 +265,7 @@ static void jffs2_wbuf_recover(struct jffs2_sb_info *c)
 
 
 	/* ... and get an allocation of space from a shiny new block instead */
-	ret = jffs2_reserve_space_gc(c, end-start, &ofs, &len);
+	ret = jffs2_reserve_space_gc(c, end-start, &ofs, &len, JFFS2_SUMMARY_NOSUM_SIZE);
 	if (ret) {
 		printk(KERN_WARNING "Failed to allocate space for wbuf recovery. Data loss ensues.\n");
 		kfree(buf);
@@ -836,6 +836,12 @@ int jffs2_flash_writev(struct jffs2_sb_info *c, const struct kvec *invecs, unsig
 alldone:
 	*retlen = donelen;
 
+	if (jffs2_sum_active()) {
+		int res = jffs2_sum_add_kvec(c, invecs, count, (uint32_t) to);
+		if (res)
+			return res;
+	}
+
 	if (c->wbuf_len && ino)
 		jffs2_wbuf_dirties_inode(c, ino);
 
@@ -855,7 +861,7 @@ int jffs2_flash_write(struct jffs2_sb_info *c, loff_t ofs, size_t len, size_t *r
 	struct kvec vecs[1];
 
 	if (!jffs2_is_writebuffered(c))
-		return c->mtd->write(c->mtd, ofs, len, retlen, buf);
+		return jffs2_flash_direct_write(c, ofs, len, retlen, buf);
 
 	vecs[0].iov_base = (unsigned char *) buf;
 	vecs[0].iov_len = len;
diff --git a/fs/jffs2/write.c b/fs/jffs2/write.c
index 0a19475..ea41151 100644
--- a/fs/jffs2/write.c
+++ b/fs/jffs2/write.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: write.c,v 1.95 2005/08/17 13:46:23 dedekind Exp $
+ * $Id: write.c,v 1.96 2005/09/07 08:34:55 havasi Exp $
  *
  */
 
@@ -153,13 +153,15 @@ struct jffs2_full_dnode *jffs2_write_dnode(struct jffs2_sb_info *c, struct jffs2
 			jffs2_dbg_acct_paranoia_check(c, jeb);
 
 			if (alloc_mode == ALLOC_GC) {
-				ret = jffs2_reserve_space_gc(c, sizeof(*ri) + datalen, &flash_ofs, &dummy);
+				ret = jffs2_reserve_space_gc(c, sizeof(*ri) + datalen, &flash_ofs,
+							&dummy, JFFS2_SUMMARY_INODE_SIZE);
 			} else {
 				/* Locking pain */
 				up(&f->sem);
 				jffs2_complete_reservation(c);
 			
-				ret = jffs2_reserve_space(c, sizeof(*ri) + datalen, &flash_ofs, &dummy, alloc_mode);
+				ret = jffs2_reserve_space(c, sizeof(*ri) + datalen, &flash_ofs,
+							&dummy, alloc_mode, JFFS2_SUMMARY_INODE_SIZE);
 				down(&f->sem);
 			}
 
@@ -299,13 +301,15 @@ struct jffs2_full_dirent *jffs2_write_dirent(struct jffs2_sb_info *c, struct jff
 			jffs2_dbg_acct_paranoia_check(c, jeb);
 
 			if (alloc_mode == ALLOC_GC) {
-				ret = jffs2_reserve_space_gc(c, sizeof(*rd) + namelen, &flash_ofs, &dummy);
+				ret = jffs2_reserve_space_gc(c, sizeof(*rd) + namelen, &flash_ofs,
+							&dummy, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 			} else {
 				/* Locking pain */
 				up(&f->sem);
 				jffs2_complete_reservation(c);
 			
-				ret = jffs2_reserve_space(c, sizeof(*rd) + namelen, &flash_ofs, &dummy, alloc_mode);
+				ret = jffs2_reserve_space(c, sizeof(*rd) + namelen, &flash_ofs,
+							&dummy, alloc_mode, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 				down(&f->sem);
 			}
 
@@ -362,7 +366,8 @@ int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 	retry:
 		D2(printk(KERN_DEBUG "jffs2_commit_write() loop: 0x%x to write to 0x%x\n", writelen, offset));
 
-		ret = jffs2_reserve_space(c, sizeof(*ri) + JFFS2_MIN_DATA_LEN, &phys_ofs, &alloclen, ALLOC_NORMAL);
+		ret = jffs2_reserve_space(c, sizeof(*ri) + JFFS2_MIN_DATA_LEN, &phys_ofs,
+					&alloclen, ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 		if (ret) {
 			D1(printk(KERN_DEBUG "jffs2_reserve_space returned %d\n", ret));
 			break;
@@ -449,7 +454,8 @@ int jffs2_do_create(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, str
 	/* Try to reserve enough space for both node and dirent. 
 	 * Just the node will do for now, though 
 	 */
-	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);
 	D1(printk(KERN_DEBUG "jffs2_do_create(): reserved 0x%x bytes\n", alloclen));
 	if (ret) {
 		up(&f->sem);
@@ -478,7 +484,8 @@ int jffs2_do_create(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, str
 
 	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. */
@@ -549,7 +556,8 @@ int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f,
 		if (!rd)
 			return -ENOMEM;
 
-		ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen, ALLOC_DELETION);
+		ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,
+					ALLOC_DELETION, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 		if (ret) {
 			jffs2_free_raw_dirent(rd);
 			return ret;
@@ -658,7 +666,8 @@ int jffs2_do_link (struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, uint
 	if (!rd)
 		return -ENOMEM;
 
-	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) {
 		jffs2_free_raw_dirent(rd);
 		return ret;
diff --git a/fs/jffs2/writev.c b/fs/jffs2/writev.c
index f079f83..6d8c27c 100644
--- a/fs/jffs2/writev.c
+++ b/fs/jffs2/writev.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: writev.c,v 1.6 2004/11/16 20:36:12 dwmw2 Exp $
+ * $Id: writev.c,v 1.7 2005/09/07 08:34:55 havasi Exp $
  *
  */
 
@@ -44,7 +44,37 @@ int jffs2_flash_direct_writev(struct jffs2_sb_info *c, const struct kvec *vecs,
 {
 	if (c->mtd->writev)
 		return c->mtd->writev(c->mtd, vecs, count, to, retlen);
-	else
+	else {
+		if (jffs2_sum_active()) {
+			int res;
+
+			res = jffs2_sum_add_kvec(c, vecs, count, (uint32_t) to);
+			if (res) {
+				return res;
+			}
+		}
+
 		return mtd_fake_writev(c->mtd, vecs, count, to, retlen);
+	}
 }
 
+int jffs2_flash_direct_write(struct jffs2_sb_info *c, loff_t ofs, size_t len,
+			size_t *retlen, const u_char *buf)
+{
+	int ret;
+	ret = c->mtd->write(c->mtd, ofs, len, retlen, buf);
+
+	if (jffs2_sum_active()) {
+		struct kvec vecs[1];
+		int res;
+
+		vecs[0].iov_base = (unsigned char *) buf;
+		vecs[0].iov_len = len;
+
+		res = jffs2_sum_add_kvec(c, vecs, 1, (uint32_t) ofs);
+		if (res) {
+			return res;
+		}
+	}
+	return ret;
+}
diff --git a/include/linux/jffs2.h b/include/linux/jffs2.h
index a66d0a8..acb51a3 100644
--- a/include/linux/jffs2.h
+++ b/include/linux/jffs2.h
@@ -8,7 +8,7 @@
  * For licensing information, see the file 'LICENCE' in the 
  * jffs2 directory.
  *
- * $Id: jffs2.h,v 1.36 2005/07/26 13:19:36 havasi Exp $
+ * $Id: jffs2.h,v 1.37 2005/09/07 08:34:55 havasi Exp $
  *
  */
 
@@ -28,6 +28,9 @@
 #define JFFS2_EMPTY_BITMASK 0xffff
 #define JFFS2_DIRTY_BITMASK 0x0000
 
+/* Summary node MAGIC marker */
+#define JFFS2_SUM_MAGIC	0x02851885
+
 /* We only allow a single char for length, and 0xFF is empty flash so
    we don't want it confused with a real length. Hence max 254.
 */
@@ -60,6 +63,8 @@
 #define JFFS2_NODETYPE_CLEANMARKER (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
 #define JFFS2_NODETYPE_PADDING (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 4)
 
+#define JFFS2_NODETYPE_SUMMARY (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 6)
+
 // Maybe later...
 //#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
 //#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4)
@@ -146,10 +151,24 @@ struct jffs2_raw_inode
 	uint8_t data[0];
 } __attribute__((packed));
 
+struct jffs2_summary_node{
+	jint16_t magic;
+	jint16_t nodetype; 	/* = JFFS2_NODETYPE_INODE_SUM */
+	jint32_t totlen;
+	jint32_t hdr_crc;
+	jint32_t sum_num;	/* number of sum entries*/
+	jint32_t cln_mkr;	/* clean marker size, 0 = no cleanmarker */
+	jint32_t padded;	/* sum of the size of padding nodes */
+	jint32_t sum_crc;	/* summary information crc */
+	jint32_t node_crc; 	/* node crc */
+	jint32_t sum[0]; 	/* inode summary info */
+} __attribute__((packed));
+
 union jffs2_node_union {
 	struct jffs2_raw_inode i;
 	struct jffs2_raw_dirent d;
 	struct jffs2_unknown_node u;
+	struct jffs2_summary_node s;
 };
 
 #endif /* __LINUX_JFFS2_H__ */
diff --git a/include/linux/jffs2_fs_sb.h b/include/linux/jffs2_fs_sb.h
index 1e21546..5087612 100644
--- a/include/linux/jffs2_fs_sb.h
+++ b/include/linux/jffs2_fs_sb.h
@@ -1,4 +1,4 @@
-/* $Id: jffs2_fs_sb.h,v 1.52 2005/05/19 16:12:17 gleixner Exp $ */
+/* $Id: jffs2_fs_sb.h,v 1.53 2005/09/07 08:34:56 havasi Exp $ */
 
 #ifndef _JFFS2_FS_SB
 #define _JFFS2_FS_SB
@@ -112,6 +112,8 @@ struct jffs2_sb_info {
 	uint32_t fsdata_len;
 #endif
 
+	struct jffs2_summary *summary;		/* Summary information */
+
 	/* OS-private pointer for getting back to master superblock info */
 	void *os_priv;
 };