[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>

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index 58496a03a1d2..99028af3f69e 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",