9P: Add cancelled() to the transport functions.
RDMA needs to post a buffer for each incoming reply.
Hence it needs to keep count of these and needs to be
aware of whether a flushed request has received a reply
or not.
This patch adds the cancelled() callback to the transport modules.
It is called when RFLUSH has been received and that the corresponding
request will never receive a reply.
Signed-off-by: Simon Derr <simon.derr@bull.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/include/net/9p/transport.h b/include/net/9p/transport.h
index 9a36d92..d9fa68f 100644
--- a/include/net/9p/transport.h
+++ b/include/net/9p/transport.h
@@ -40,6 +40,8 @@
* @close: member function to discard a connection on this transport
* @request: member function to issue a request to the transport
* @cancel: member function to cancel a request (if it hasn't been sent)
+ * @cancelled: member function to notify that a cancelled request will not
+ * not receive a reply
*
* This is the basic API for a transport module which is registered by the
* transport module with the 9P core network module and used by the client
@@ -58,6 +60,7 @@
void (*close) (struct p9_client *);
int (*request) (struct p9_client *, struct p9_req_t *req);
int (*cancel) (struct p9_client *, struct p9_req_t *req);
+ int (*cancelled)(struct p9_client *, struct p9_req_t *req);
int (*zc_request)(struct p9_client *, struct p9_req_t *,
char *, char *, int , int, int, int);
};
diff --git a/net/9p/client.c b/net/9p/client.c
index d18a0b2..8b93cae 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -658,12 +658,18 @@
/*
* if we haven't received a response for oldreq,
- * remove it from the list.
+ * remove it from the list, and notify the transport
+ * layer that the reply will never arrive.
*/
spin_lock(&c->lock);
- if (oldreq->status == REQ_STATUS_FLSH)
+ if (oldreq->status == REQ_STATUS_FLSH) {
list_del(&oldreq->req_list);
- spin_unlock(&c->lock);
+ spin_unlock(&c->lock);
+ if (c->trans_mod->cancelled)
+ c->trans_mod->cancelled(c, req);
+ } else {
+ spin_unlock(&c->lock);
+ }
p9_free_req(c, req);
return 0;
diff --git a/net/9p/trans_rdma.c b/net/9p/trans_rdma.c
index 8f68df5..928f2bb 100644
--- a/net/9p/trans_rdma.c
+++ b/net/9p/trans_rdma.c
@@ -588,6 +588,17 @@
return 1;
}
+/* A request has been fully flushed without a reply.
+ * That means we have posted one buffer in excess.
+ */
+static int rdma_cancelled(struct p9_client *client, struct p9_req_t *req)
+{
+ struct p9_trans_rdma *rdma = client->trans;
+
+ atomic_inc(&rdma->excess_rc);
+ return 0;
+}
+
/**
* trans_create_rdma - Transport method for creating atransport instance
* @client: client instance