From: NeilBrown <neilb@suse.de>
Date: Tue, 3 May 2011 05:47:09 +0000 (+1000)
Subject: FORMAT CHANGE use crc32 instead of toy checksum for cluster head
X-Git-Url: http://git.neil.brown.name/?a=commitdiff_plain;h=1564bb35d79bd981605b5b629d8308ebce690007;p=LaFS.git

FORMAT CHANGE use crc32 instead of toy checksum for cluster head

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/cluster.c b/cluster.c
index 7ab4043..6233fb8 100644
--- a/cluster.c
+++ b/cluster.c
@@ -42,6 +42,7 @@
  */
 
 #include	"lafs.h"
+#include	<linux/crc32.h>
 #include	<linux/random.h>
 #include	<linux/slab.h>
 
@@ -1073,17 +1074,12 @@ lafs_cluster_update_abort(struct update_handle *uh)
 int lafs_calc_cluster_csum(struct cluster_head *head)
 {
 	unsigned int oldcsum = head->checksum;
-	unsigned long long newcsum = 0;
 	unsigned long csum;
-	int i;
-	unsigned int *superc = (unsigned int *) head;
-	head->checksum = 0;
 
-	for (i = 0; i < le16_to_cpu(head->Hlength)/4; i++)
-		newcsum += le32_to_cpu(superc[i]);
-	csum = (newcsum & 0xffffffff) + (newcsum>>32);
+	head->checksum = 0;
+	csum = crc32_le(0, (unsigned char *)head, le16_to_cpu(head->Hlength));
 	head->checksum = oldcsum;
-	return cpu_to_le32(csum);
+	return csum;
 }
 
 /*------------------------------------------------------------------------