rpc: track number of users of the gss upcall pipe

Keep a count of the number of pipes open plus the number of messages on
a pipe.  This count isn't used yet.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index bc512fff8a41..51aa27d32b5a 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -75,6 +75,8 @@ struct gss_auth {
         struct dentry *dentry;
 };
 
+static atomic_t pipe_users = ATOMIC_INIT(0);
+
 static void gss_free_ctx(struct gss_cl_ctx *);
 static struct rpc_pipe_ops gss_upcall_ops;
 
@@ -237,6 +239,7 @@ gss_release_msg(struct gss_upcall_msg *gss_msg)
 {
         if (!atomic_dec_and_test(&gss_msg->count))
                 return;
+        atomic_dec(&pipe_users);
         BUG_ON(!list_empty(&gss_msg->list));
         if (gss_msg->ctx != NULL)
                 gss_put_ctx(gss_msg->ctx);
@@ -331,6 +334,7 @@ gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid)
         gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
         if (gss_msg == NULL)
                 return ERR_PTR(-ENOMEM);
+        atomic_inc(&pipe_users);
         INIT_LIST_HEAD(&gss_msg->list);
         rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
         init_waitqueue_head(&gss_msg->waitqueue);
@@ -555,6 +559,13 @@ out:
         return err;
 }
 
+static int
+gss_pipe_open(struct inode *inode)
+{
+        atomic_inc(&pipe_users);
+        return 0;
+}
+
 static void
 gss_pipe_release(struct inode *inode)
 {
@@ -574,6 +585,8 @@ gss_pipe_release(struct inode *inode)
                 spin_lock(&inode->i_lock);
         }
         spin_unlock(&inode->i_lock);
+
+        atomic_dec(&pipe_users);
 }
 
 static void
@@ -1349,6 +1362,7 @@ static struct rpc_pipe_ops gss_upcall_ops = {
         .upcall         = gss_pipe_upcall,
         .downcall       = gss_pipe_downcall,
         .destroy_msg    = gss_pipe_destroy_msg,
+        .open_pipe      = gss_pipe_open,
         .release_pipe   = gss_pipe_release,
 };