Skip to contentSkip to conversation

AFS: Correctly use 64-bit time for UUID

PATCH In review Tina Ruchandani 2 participants 2 messages Jan 29, 2015 – Feb 11, 2015 Afs filesystem

lore
Share & tools
lore

Tina Ruchandani

author
#0 lore raw

PATCH 1/1 AFS: Correctly use 64-bit time for UUID

UUID calculation uses 'struct timespec' whose seconds will overflow in year 2038 and beyond for 32-bit systems. This patch removes the dependency on 'struct timespec' by using ktime_get_real_ns(). While the patch does not fix a 'bug' as such, it is part of a larger effort to remove instances of 'struct timespec' and other data-structures suffering from y2038 problem from the kernel.

Suggested-by Arnd Bergmann <[email protected]>
Signed-off-by Tina Ruchandani <[email protected]>
---
 fs/afs/main.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
fs/afs/main.c +2 -4
index 35de0c0..7a9c2e6 100644
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/completion.h>
 #include <linux/sched.h>
+#include <linux/ktime.h>
 #include "internal.h"
 
 MODULE_DESCRIPTION("AFS Client File System");

@@ -37,7 +38,6 @@ struct workqueue_struct *afs_wq;
  */
 static int __init afs_get_client_UUID(void)
 {
-	struct timespec ts;
 	u64 uuidtime;
 	u16 clockseq;
 	int ret;

@@ -48,9 +48,7 @@ static int __init afs_get_client_UUID(void)
 	if (ret < 0)
 		return ret;
 
-	getnstimeofday(&ts);
-	uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10;
-	uuidtime += ts.tv_nsec / 100;
+	uuidtime = ktime_get_real_ns() / 100;
 	uuidtime += AFS_UUID_TO_UNIX_TIME;
 	afs_uuid.time_low = uuidtime;
 	afs_uuid.time_mid = uuidtime >> 32;
Signature · 1 line
2.2.0.rc0.207.ga3a616c
maintainer
#1 lore raw

fs/afs/main.c static int __init afs_get_client_UUID(void) · line 51

Quoted 1 line · Tina Ruchandani
fs/afs/main.c +1 -0
+	uuidtime = ktime_get_real_ns() / 100;

64-bit division must be done using asm/div64.h

David