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>

1 files changed, 7 insertions, 6 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index b750aa502ff7..3610e9958b4c 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -986,19 +986,19 @@ static int cifs_oplock_thread(void *dummyarg)
                 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 @@ init_cifs(void)
         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 @@ init_cifs(void)
         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;