netfs: Make netfs_put_request() handle a NULL pointer

Make netfs_put_request() just return if given a NULL request pointer.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org

diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c
index 65a17dd4ab492c9ed07dabeac0e2ff7b68b52e14..3aa0bfbc04ec3b00e5e31b4a7fd540a41a44afe8 100644 (file)
--- a/fs/netfs/objects.c
+++ b/fs/netfs/objects.c
@@ -106,19 +106,22 @@ static void netfs_free_request(struct work_struct *work)
 void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
                       enum netfs_rreq_ref_trace what)
 {
-       unsigned int debug_id = rreq->debug_id;
+       unsigned int debug_id;
        bool dead;
        int r;
 
-       dead = __refcount_dec_and_test(&rreq->ref, &r);
-       trace_netfs_rreq_ref(debug_id, r - 1, what);
-       if (dead) {
-               if (was_async) {
-                       rreq->work.func = netfs_free_request;
-                       if (!queue_work(system_unbound_wq, &rreq->work))
-                               BUG();
-               } else {
-                       netfs_free_request(&rreq->work);
+       if (rreq) {
+               debug_id = rreq->debug_id;
+               dead = __refcount_dec_and_test(&rreq->ref, &r);
+               trace_netfs_rreq_ref(debug_id, r - 1, what);
+               if (dead) {
+                       if (was_async) {
+                               rreq->work.func = netfs_free_request;
+                               if (!queue_work(system_unbound_wq, &rreq->work))
+                                       BUG();
+                       } else {
+                               netfs_free_request(&rreq->work);
+                       }
                }
        }
 }