Filter incoming requests per card

If multiple cards are installed, firewire-core will emit requests from
nodes on any of the cards to clients.  This is not expected by
libraw1394 clients since a raw1394handle_t is bound to a single card
alias port.

On kernel 2.6.36 and newer we can filter out requests from other cards.
Note that we still need to call the response ioctl in order to release
kernel resources associated with an inbound transaction.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

src/fw.c

@@ -220,14 +220,14 @@ handle_lost_device(fw_handle_t handle, int i)
 struct address_closure {
 	int (*callback)(raw1394handle_t handle, struct address_closure *ac,
 			int tcode, unsigned long long offset,
-			int source_node_id, unsigned kernel_handle,
+			int source_node_id, int card, unsigned kernel_handle,
 			size_t length, void *data);
 };
 
 static int
 handle_fcp_request(raw1394handle_t handle, struct address_closure *ac,
 		   int tcode, unsigned long long offset, int source_node_id,
-		   unsigned kernel_handle, size_t length, void *data)
+		   int card, unsigned kernel_handle, size_t length, void *data)
 {
 	struct fw_cdev_send_response response;
 	int is_response;
@@ -247,6 +247,9 @@ handle_fcp_request(raw1394handle_t handle, struct address_closure *ac,
 		  FW_CDEV_IOC_SEND_RESPONSE, &response) < 0)
 		return -1;
 
+	if (card != handle->mode.fw->card)
+		return 0;
+
 	if (response.rcode != RCODE_COMPLETE)
 		return 0;
 
@@ -315,6 +318,7 @@ handle_device_event(raw1394handle_t handle,
 				    u->request.offset,
 				    /* wild guess, but can't do better */
 				    fwhandle->devices[i].node_id,
+				    fwhandle->card,
 				    u->request.handle,
 				    u->request.length, u->request.data);
 
@@ -324,6 +328,7 @@ handle_device_event(raw1394handle_t handle,
 		return ac->callback(handle, ac, u->request2.tcode,
 				    u->request2.offset,
 				    u->request2.source_node_id,
+				    u->request2.card,
 				    u->request2.handle,
 				    u->request2.length, u->request2.data);
 #endif
@@ -673,6 +678,7 @@ int fw_set_port(fw_handle_t handle, int port)
 		if (reset.node_id == reset.local_node_id)
 			handle->local_device = &handle->devices[i];
 
+		handle->card = get_info.card;
 		handle->generation = reset.generation;
 		handle->abi_version = get_info.version;
 
@@ -730,7 +736,7 @@ struct allocation {
 static int
 handle_arm_request(raw1394handle_t handle, struct address_closure *ac,
 		   int tcode, unsigned long long offset, int source_node_id,
-		   unsigned kernel_handle, size_t length, void *data)
+		   int card, unsigned kernel_handle, size_t length, void *data)
 {
 	fw_handle_t fwhandle = handle->mode.fw;
 	struct allocation *allocation = (struct allocation *) ac;
@@ -809,6 +815,13 @@ handle_arm_request(raw1394handle_t handle, struct address_closure *ac,
 			return -1;
 	}
 
+	/*
+	 * libraw1394 clients do not expect requests from nodes on
+	 * a card other than the one set by raw1394_set_port().
+	 */
+	if (card != fwhandle->card)
+		return 0;
+
 	if (!(allocation->notification_options & type))
 		return 0;
 

src/fw.h

@@ -79,6 +79,7 @@ struct fw_handle {
 	struct port ports[MAX_PORTS];
 	int port_count;
 	int err;
+	int card;
 	int generation;
 	int abi_version;
 	void *userdata;