gfs2: make gfs2_holder.gh_owner_pid be a struct pid *

The gl_owner_pid field is used to get the holder task by its pid and check
whether the current is a holder, so make it in a proper manner, i.e.  via the
struct pid * manipulations.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index b16f604..2f9c6d1 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -36,11 +36,13 @@
 {
 	struct gfs2_holder *gh;
 	int locked = 0;
+	struct pid *pid;
 
 	/* Look in glock's list of holders for one with current task as owner */
 	spin_lock(&gl->gl_spin);
+	pid = task_pid(current);
 	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
-		if (gh->gh_owner_pid == current->pid) {
+		if (gh->gh_owner_pid == pid) {
 			locked = 1;
 			break;
 		}