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From: =?ISO-8859-1?Q?=D8yvind?= Harboe <oyvind.harboe@zylin.com>
To: linux-mtd@lists.infradead.org
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Date: Wed, 31 Aug 2005 11:28:12 +0200
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Subject: PATCH: allow JFFS2 to write to really small disks
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The attached patch allows JFFS2 to write to really small JFFS2 disks.

This is e.g. useful when using JFFS2 for in-system one time programming
of embedded device parameters: serial number, MAC, etc.


Comments?

--=20
=D8yvind Harboe
http://www.zylin.com

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Index: build.c
===================================================================
RCS file: /home/cvs/mtd/fs/jffs2/build.c,v
retrieving revision 1.76
diff -u -r1.76 build.c
--- build.c    30 Jul 2005 15:29:27 -0000	1.76
+++ build.c    31 Aug 2005 09:01:34 -0000
@@ -279,6 +279,14 @@
 
	c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size);
 
+	/* If the flash disk is smaller than resv_blocks_write, then we 
+	   allow writing to the disk anyway. The flash disk is then most likely
+	      being used as write once - read many medimum, e.g. in-system configuration of 
+	         static parameters(e.g. MAC address of device in stored in "ROM"). */
+		 if (c->resv_blocks_write * c->sector_size > c->flash_size) {
+		   c->resv_blocks_write = 0; 
+		   }
+
	/* When do we let the GC thread run in the background */
 
	c->resv_blocks_gctrigger = c->resv_blocks_write + 1;

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