cifs: reinstate sharing of tree connections

Use a similar approach to the SMB session sharing. Add a list of tcons
attached to each SMB session. Move the refcount to non-atomic. Protect
all of the above with the cifs_tcp_ses_lock. Add functions to
properly find and put references to the tcons.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index a1e96620b097..d9cf467309e8 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -514,10 +514,11 @@ static void cifs_umount_begin(struct super_block *sb)
         tcon = cifs_sb->tcon;
         if (tcon == NULL)
                 return;
-        down(&tcon->tconSem);
-        if (atomic_read(&tcon->useCount) == 1)
+
+        read_lock(&cifs_tcp_ses_lock);
+        if (tcon->tc_count == 1)
                 tcon->tidStatus = CifsExiting;
-        up(&tcon->tconSem);
+        read_unlock(&cifs_tcp_ses_lock);
 
         /* cancel_brl_requests(tcon); */ /* BB mark all brl mids as exiting */
         /* cancel_notify_requests(tcon); */
@@ -1060,7 +1061,6 @@ init_cifs(void)
         int rc = 0;
         cifs_proc_init();
         INIT_LIST_HEAD(&cifs_tcp_ses_list);
-        INIT_LIST_HEAD(&GlobalTreeConnectionList); /* BB to be removed by jl */
         INIT_LIST_HEAD(&GlobalOplock_Q);
 #ifdef CONFIG_CIFS_EXPERIMENTAL
         INIT_LIST_HEAD(&GlobalDnotifyReqList);