9P: Add cancelled() to the transport functions.

And move transport-specific code out of net/9p/client.c
Signed-off-by: Simon Derr <simon.derr@bull.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

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 @@ struct p9_trans_module {
 	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);
 };

net/9p/client.c

@@ -663,16 +663,13 @@ static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
-
 	/*
 	 * if we haven't received a response for oldreq,
 	 * remove it from the list
 	 */
-	if (oldreq->status == REQ_STATUS_FLSH) {
-		spin_lock(&c->lock);
-		list_del(&oldreq->req_list);
-		spin_unlock(&c->lock);
-	}
+	if (oldreq->status == REQ_STATUS_FLSH)
+		if (c->trans_mod->cancelled)
+			c->trans_mod->cancelled(c, oldreq);
 
 	p9_free_req(c, req);
 	return 0;

net/9p/trans_fd.c

@@ -709,6 +709,20 @@ static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req)
 	return ret;
 }
 
+static int p9_fd_cancelled(struct p9_client *client, struct p9_req_t *req)
+{
+	p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req);
+
+	/* we haven't received a response for oldreq,
+	 * remove it from the list.
+	 */
+	spin_lock(&client->lock);
+	list_del(&req->req_list);
+	spin_unlock(&client->lock);
+
+	return 0;
+}
+
 /**
  * parse_opts - parse mount options into p9_fd_opts structure
  * @params: options string passed from mount
@@ -1050,6 +1064,7 @@ static struct p9_trans_module p9_tcp_trans = {
 	.close = p9_fd_close,
 	.request = p9_fd_request,
 	.cancel = p9_fd_cancel,
+	.cancelled = p9_fd_cancelled,
 	.owner = THIS_MODULE,
 };
 
@@ -1061,6 +1076,7 @@ static struct p9_trans_module p9_unix_trans = {
 	.close = p9_fd_close,
 	.request = p9_fd_request,
 	.cancel = p9_fd_cancel,
+	.cancelled = p9_fd_cancelled,
 	.owner = THIS_MODULE,
 };
 
@@ -1072,6 +1088,7 @@ static struct p9_trans_module p9_fd_trans = {
 	.close = p9_fd_close,
 	.request = p9_fd_request,
 	.cancel = p9_fd_cancel,
+	.cancelled = p9_fd_cancelled,
 	.owner = THIS_MODULE,
 };