[PATCH] mtd corruption fix

Read the return value before we release the nand device otherwise the
value can become corrupted by another user of chip->ops, ultimately
resulting in filesystem corruption.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: NJosh Boyer <jwboyer@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/mtd/nand/nand_base.c

@@ -1093,9 +1093,10 @@ static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
 
 	ret = nand_do_read_ops(mtd, from, &chip->ops);
 
+	*retlen = chip->ops.retlen;
+
 	nand_release_device(mtd);
 
-	*retlen = chip->ops.retlen;
 	return ret;
 }
 
@@ -1691,9 +1692,10 @@ static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
 
 	ret = nand_do_write_ops(mtd, to, &chip->ops);
 
+	*retlen = chip->ops.retlen;
+
 	nand_release_device(mtd);
 
-	*retlen = chip->ops.retlen;
 	return ret;
 }