struct timespec is not y2038 safe.  Use time64_t which is y2038 safe to
represent orphan scan times.  time64_t is sufficient here as only the
seconds delta times are relevant.
Also use appropriate time functions that return time in time64_t format.
Time functions now return monotonic time instead of real time as only
delta scan times are relevant and these values are not persistent across
reboots.
The format string for the debug print is still using long as this is
only the time elapsed since the last scan and long is sufficient to
represent this value.
Link: http://lkml.kernel.org/r/1475365138-20567-1-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 
         */
        seqno++;
        os->os_count++;
-       os->os_scantime = CURRENT_TIME;
+       os->os_scantime = ktime_get_seconds();
 unlock:
        ocfs2_orphan_scan_unlock(osb, seqno);
 out:
        struct ocfs2_orphan_scan *os;
 
        os = &osb->osb_orphan_scan;
-       os->os_scantime = CURRENT_TIME;
+       os->os_scantime = ktime_get_seconds();
        if (ocfs2_is_hard_readonly(osb) || ocfs2_mount_local(osb))
                atomic_set(&os->os_state, ORPHAN_SCAN_INACTIVE);
        else {
 
        struct ocfs2_super      *os_osb;
        struct ocfs2_lock_res   os_lockres;     /* lock to synchronize scans */
        struct delayed_work     os_orphan_scan_work;
-       struct timespec         os_scantime;  /* time this node ran the scan */
+       time64_t                os_scantime;  /* time this node ran the scan */
        u32                     os_count;      /* tracks node specific scans */
        u32                     os_seqno;       /* tracks cluster wide scans */
        atomic_t                os_state;              /* ACTIVE or INACTIVE */
 
                out += snprintf(buf + out, len - out, "Disabled\n");
        else
                out += snprintf(buf + out, len - out, "%lu seconds ago\n",
-                               (get_seconds() - os->os_scantime.tv_sec));
+                               (unsigned long)(ktime_get_seconds() - os->os_scantime));
 
        out += snprintf(buf + out, len - out, "%10s => %3s  %10s\n",
                        "Slots", "Num", "RecoGen");