openwrt/target/linux/generic-2.4/patches/227-jffs2_eofdetect.patch

--- a/fs/jffs2/build.c
+++ b/fs/jffs2/build.c
@@ -31,6 +31,10 @@
  * provisions above, a recipient may use your version of this file
  * under either the RHEPL or the GPL.
  *
+ * Modification for automatically cleaning the filesystem after
+ * a specially marked block
+ * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
+ *
  * $Id: build.c,v 1.16.2.3 2003/04/30 09:43:32 dwmw2 Exp $
  *
  */
@@ -38,6 +42,7 @@
 #include <linux/kernel.h>
 #include <linux/jffs2.h>
 #include <linux/slab.h>
+#include <linux/mtd/mtd.h>
 #include "nodelist.h"
 
 int jffs2_build_inode_pass1(struct jffs2_sb_info *, struct jffs2_inode_cache *);
@@ -89,6 +94,18 @@ int jffs2_build_filesystem(struct jffs2_
 	if (ret)
 		return ret;
 
+	if (c->flags & (1 << 7)) {
+		printk("%s(): unlocking the mtd device... ", __func__);
+		if (c->mtd->unlock)
+			c->mtd->unlock(c->mtd, 0, c->mtd->size);
+		printk("done.\n");
+		
+		printk("%s(): erasing all blocks after the end marker... ", __func__);
+		jffs2_erase_pending_blocks(c);
+		jffs2_mark_erased_blocks(c);
+		printk("done.\n");
+	}
+
 	D1(printk(KERN_DEBUG "Scanned flash completely\n"));
 	/* Now build the data map for each inode, marking obsoleted nodes
 	   as such, and also increase nlink of any children. */
--- a/fs/jffs2/scan.c
+++ b/fs/jffs2/scan.c
@@ -31,6 +31,10 @@
  * provisions above, a recipient may use your version of this file
  * under either the RHEPL or the GPL.
  *
+ * Modification for automatically cleaning the filesystem after
+ * a specially marked block
+ * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
+ *
  * $Id: scan.c,v 1.51.2.4 2003/11/02 13:51:18 dwmw2 Exp $
  *
  */
@@ -88,7 +92,12 @@ int jffs2_scan_medium(struct jffs2_sb_in
 	for (i=0; i<c->nr_blocks; i++) {
 		struct jffs2_eraseblock *jeb = &c->blocks[i];
 
-		ret = jffs2_scan_eraseblock(c, jeb);
+
+		if (c->flags & (1 << 7))
+			ret = 1;
+		else
+			ret = jffs2_scan_eraseblock(c, jeb);
+
 		if (ret < 0)
 			return ret;
 
@@ -181,6 +190,7 @@ static int jffs2_scan_eraseblock (struct
 
 	while(ofs < jeb->offset + c->sector_size) {
 		ssize_t retlen;
+		unsigned char *buf = (unsigned char *) &node;
 		ACCT_PARANOIA_CHECK(jeb);
 		
 		if (ofs & 3) {
@@ -202,8 +212,18 @@ static int jffs2_scan_eraseblock (struct
 			break;
 		}
 
-		err = c->mtd->read(c->mtd, ofs, sizeof(node), &retlen, (char *)&node);
+		err = c->mtd->read(c->mtd, ofs, sizeof(node), &retlen, buf);
+		if ((buf[0] == 0xde) &&
+			(buf[1] == 0xad) &&
+			(buf[2] == 0xc0) &&
+			(buf[3] == 0xde)) {
+				
+			/* end of filesystem. erase everything after this point */
+			c->flags |= (1 << 7);
+			printk("jffs2_scan_eraseblock(): End of filesystem marker found at 0x%x\n", jeb->offset);
 		
+			return 1;
+		}
 		if (err) {
 			D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", sizeof(node), ofs, err));
 			return err;