fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp

get_seconds() is deprecated in favor of ktime_get_real_seconds(), which
returns a 64-bit timestamp.

In the SYSV file system, the superblock timestamp is only 32 bits wide,
and it is used to check whether a file system is clean, so the best
solution seems to be to force a wraparound and explicitly convert it to an
unsigned 32-bit value.

This is independent of the inode timestamps that are also 32-bit wide on
disk and that come from current_time().

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnd Bergmann <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: David Howells <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

fs/sysv/inode.c

@@ -35,7 +35,7 @@
 static int sysv_sync_fs(struct super_block *sb, int wait)
 {
 	struct sysv_sb_info *sbi = SYSV_SB(sb);
-	unsigned long time = get_seconds(), old_time;
+	u32 time = (u32)ktime_get_real_seconds(), old_time;
 
 	mutex_lock(&sbi->s_lock);
 
@@ -46,8 +46,8 @@ static int sysv_sync_fs(struct super_block *sb, int wait)
 	 */
 	old_time = fs32_to_cpu(sbi, *sbi->s_sb_time);
 	if (sbi->s_type == FSTYPE_SYSV4) {
-		if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time))
-			*sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time);
+		if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38u - old_time))
+			*sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38u - time);
 		*sbi->s_sb_time = cpu_to_fs32(sbi, time);
 		mark_buffer_dirty(sbi->s_bh2);
 	}