From: Matthieu CASTET <matthieu.castet@parrot.com>
Date: Fri, 19 Oct 2012 15:29:33 +0000 (+0200)
Subject: mtdoops: don't erase flash at each boot
X-Git-Tag: next-20121113~72^2~1
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=686939ff908f658e8714dde87c3839f05de4ef32;p=karo-tx-linux.git

mtdoops: don't erase flash at each boot

If there is no oops stored (flash is erased), find_next_position will
exit with maxcount == 0xffffffff and erase the first page.

Only erase it if mark_is_used.

Signed-off-by: Matthieu Castet <matthieu.castet@parrot@com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---

diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index f5b3f91fa1cc..97bb8f6304d4 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -271,7 +271,7 @@ static void find_next_position(struct mtdoops_context *cxt)
 
 		if (count[0] == 0xffffffff && count[1] == 0xffffffff)
 			mark_page_unused(cxt, page);
-		if (count[0] == 0xffffffff)
+		if (count[0] == 0xffffffff || count[1] != MTDOOPS_KERNMSG_MAGIC)
 			continue;
 		if (maxcount == 0xffffffff) {
 			maxcount = count[0];
@@ -289,14 +289,13 @@ static void find_next_position(struct mtdoops_context *cxt)
 		}
 	}
 	if (maxcount == 0xffffffff) {
-		cxt->nextpage = 0;
-		cxt->nextcount = 1;
-		schedule_work(&cxt->work_erase);
-		return;
+		cxt->nextpage = cxt->oops_pages - 1;
+		cxt->nextcount = 0;
+	}
+	else {
+		cxt->nextpage = maxpos;
+		cxt->nextcount = maxcount;
 	}
-
-	cxt->nextpage = maxpos;
-	cxt->nextcount = maxcount;
 
 	mtdoops_inc_counter(cxt);
 }