nfsd: make nfsd4_run_cb a bool return function

queue_work can return false and not queue anything, if the work is
already queued. If that happens in the case of a CB_RECALL, we'll have
taken an extra reference to the stid that will never be put. Ensure we
throw a warning in that case.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 4ce328209f61..f0e69edf5f0f 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1371,11 +1371,21 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
 	cb->cb_holds_slot = false;
 }
 
-void nfsd4_run_cb(struct nfsd4_callback *cb)
+/**
+ * nfsd4_run_cb - queue up a callback job to run
+ * @cb: callback to queue
+ *
+ * Kick off a callback to do its thing. Returns false if it was already
+ * on a queue, true otherwise.
+ */
+bool nfsd4_run_cb(struct nfsd4_callback *cb)
 {
 	struct nfs4_client *clp = cb->cb_clp;
+	bool queued;
 
 	nfsd41_cb_inflight_begin(clp);
-	if (!nfsd4_queue_cb(cb))
+	queued = nfsd4_queue_cb(cb);
+	if (!queued)
 		nfsd41_cb_inflight_end(clp);
+	return queued;
 }