cifs: protect GlobalOplock_Q with its own spinlock

Right now, the GlobalOplock_Q is protected by the GlobalMid_Lock. That
lock is also used for completely unrelated purposes (mostly for managing
the global mid queue). Give the list its own dedicated spinlock
(cifs_oplock_lock) and rename the list to cifs_oplock_list to
eliminate the camel-case.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index b750aa5..3610e99 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -986,19 +986,19 @@
 		if (try_to_freeze())
 			continue;
 
-		spin_lock(&GlobalMid_Lock);
-		if (list_empty(&GlobalOplock_Q)) {
-			spin_unlock(&GlobalMid_Lock);
+		spin_lock(&cifs_oplock_lock);
+		if (list_empty(&cifs_oplock_list)) {
+			spin_unlock(&cifs_oplock_lock);
 			set_current_state(TASK_INTERRUPTIBLE);
 			schedule_timeout(39*HZ);
 		} else {
-			oplock_item = list_entry(GlobalOplock_Q.next,
+			oplock_item = list_entry(cifs_oplock_list.next,
 						struct oplock_q_entry, qhead);
 			cFYI(1, ("found oplock item to write out"));
 			pTcon = oplock_item->tcon;
 			inode = oplock_item->pinode;
 			netfid = oplock_item->netfid;
-			spin_unlock(&GlobalMid_Lock);
+			spin_unlock(&cifs_oplock_lock);
 			DeleteOplockQEntry(oplock_item);
 			/* can not grab inode sem here since it would
 				deadlock when oplock received on delete
@@ -1055,7 +1055,7 @@
 	int rc = 0;
 	cifs_proc_init();
 	INIT_LIST_HEAD(&cifs_tcp_ses_list);
-	INIT_LIST_HEAD(&GlobalOplock_Q);
+	INIT_LIST_HEAD(&cifs_oplock_list);
 #ifdef CONFIG_CIFS_EXPERIMENTAL
 	INIT_LIST_HEAD(&GlobalDnotifyReqList);
 	INIT_LIST_HEAD(&GlobalDnotifyRsp_Q);
@@ -1084,6 +1084,7 @@
 	rwlock_init(&GlobalSMBSeslock);
 	rwlock_init(&cifs_tcp_ses_lock);
 	spin_lock_init(&GlobalMid_Lock);
+	spin_lock_init(&cifs_oplock_lock);
 
 	if (cifs_max_pending < 2) {
 		cifs_max_pending = 2;