[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, 19 insertions, 10 deletions

diff --git a/fs/jffs2/write.c b/fs/jffs2/write.c
index 0a194759bbb..ea411518d80 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;