dlm: eliminate astparam type casting

Put lkb_astparam in a union with a dlm_user_args pointer to
eliminate a lot of type casting.

Signed-off-by: David Teigland <teigland@redhat.com>
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 94f8cbd..8f250ac 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -4533,7 +4533,7 @@
 	/* user can change the params on its lock when it converts it, or
 	   add an lvb that didn't exist before */
 
-	ua = (struct dlm_user_args *)lkb->lkb_astparam;
+	ua = lkb->lkb_ua;
 
 	if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
 		ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_KERNEL);
@@ -4584,7 +4584,7 @@
 	if (error)
 		goto out;
 
-	ua = (struct dlm_user_args *)lkb->lkb_astparam;
+	ua = lkb->lkb_ua;
 
 	if (lvb_in && ua->lksb.sb_lvbptr)
 		memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
@@ -4633,7 +4633,7 @@
 	if (error)
 		goto out;
 
-	ua = (struct dlm_user_args *)lkb->lkb_astparam;
+	ua = lkb->lkb_ua;
 	if (ua_tmp->castparam)
 		ua->castparam = ua_tmp->castparam;
 	ua->user_lksb = ua_tmp->user_lksb;
@@ -4671,7 +4671,7 @@
 	if (error)
 		goto out;
 
-	ua = (struct dlm_user_args *)lkb->lkb_astparam;
+	ua = lkb->lkb_ua;
 
 	error = set_unlock_args(flags, ua, &args);
 	if (error)
@@ -4710,7 +4710,6 @@
 
 static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
 {
-	struct dlm_user_args *ua = (struct dlm_user_args *)lkb->lkb_astparam;
 	struct dlm_args args;
 	int error;
 
@@ -4719,7 +4718,7 @@
 	list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
 	mutex_unlock(&ls->ls_orphans_mutex);
 
-	set_unlock_args(0, ua, &args);
+	set_unlock_args(0, lkb->lkb_ua, &args);
 
 	error = cancel_lock(ls, lkb, &args);
 	if (error == -DLM_ECANCEL)
@@ -4732,11 +4731,10 @@
 
 static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
 {
-	struct dlm_user_args *ua = (struct dlm_user_args *)lkb->lkb_astparam;
 	struct dlm_args args;
 	int error;
 
-	set_unlock_args(DLM_LKF_FORCEUNLOCK, ua, &args);
+	set_unlock_args(DLM_LKF_FORCEUNLOCK, lkb->lkb_ua, &args);
 
 	error = unlock_lock(ls, lkb, &args);
 	if (error == -DLM_EUNLOCK)