firewire: Streamline userspace interface structs.

Make event struct layout common part include the closure and add a
union for all event types; provide a mechanism for setting the
bus reset event closure.

Shuffle struct fw_cdev_queue_iso fields around to be 64-bit safe.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/fw-device-cdev.c

@@ -79,6 +79,7 @@ struct client {
 	u32 request_serial;
 	struct list_head event_list;
 	wait_queue_head_t wait;
+	u64 bus_reset_closure;
 
 	struct fw_iso_context *iso_context;
 	struct fw_iso_buffer buffer;
@@ -199,12 +200,13 @@ fw_device_op_read(struct file *file,
 
 static void
 fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
-		     struct fw_device *device)
+		     struct client *client)
 {
-	struct fw_card *card = device->card;
+	struct fw_card *card = client->device->card;
 
+	event->closure	     = client->bus_reset_closure;
 	event->type          = FW_CDEV_EVENT_BUS_RESET;
-	event->node_id       = device->node_id;
+	event->node_id       = client->device->node_id;
 	event->local_node_id = card->local_node->node_id;
 	event->bm_node_id    = 0; /* FIXME: We don't track the BM. */
 	event->irm_node_id   = card->irm_node->node_id;
@@ -232,7 +234,6 @@ static void
 queue_bus_reset_event(struct client *client)
 {
 	struct bus_reset *bus_reset;
-	struct fw_device *device = client->device;
 
 	bus_reset = kzalloc(sizeof *bus_reset, GFP_ATOMIC);
 	if (bus_reset == NULL) {
@@ -240,7 +241,7 @@ queue_bus_reset_event(struct client *client)
 		return;
 	}
 
-	fill_bus_reset_event(&bus_reset->reset, device);
+	fill_bus_reset_event(&bus_reset->reset, client);
 
 	queue_event(client, &bus_reset->event,
 		    &bus_reset->reset, sizeof bus_reset->reset, NULL, 0);
@@ -283,10 +284,11 @@ static int ioctl_get_info(struct client *client, void __user *arg)
 	}
 	get_info.rom_length = client->device->config_rom_length * 4;
 
+	client->bus_reset_closure = get_info.bus_reset_closure;
 	if (get_info.bus_reset != 0) {
 		void __user *uptr = u64_to_uptr(get_info.bus_reset);
 
-		fill_bus_reset_event(&bus_reset, client->device);
+		fill_bus_reset_event(&bus_reset, client);
 		if (copy_to_user(uptr, &bus_reset, sizeof bus_reset))
 			return -EFAULT;
 	}

drivers/firewire/fw-device-cdev.h

@@ -74,7 +74,13 @@
  * event.  It's a 64-bit type so that it's a fixed size type big
  * enough to hold a pointer on all platforms. */
 
+struct fw_cdev_event_common {
+	__u64 closure;
+	__u32 type;
+};
+
 struct fw_cdev_event_bus_reset {
+	__u64 closure;
 	__u32 type;
 	__u32 node_id;
 	__u32 local_node_id;
@@ -85,31 +91,39 @@ struct fw_cdev_event_bus_reset {
 };
 
 struct fw_cdev_event_response {
+	__u64 closure;
 	__u32 type;
 	__u32 rcode;
-	__u64 closure;
 	__u32 length;
 	__u32 data[0];
 };
 
 struct fw_cdev_event_request {
+	__u64 closure;
 	__u32 type;
 	__u32 tcode;
 	__u64 offset;
-	__u64 closure;
 	__u32 serial;
 	__u32 length;
 	__u32 data[0];
 };
 
 struct fw_cdev_event_iso_interrupt {
+	__u64 closure;
 	__u32 type;
 	__u32 cycle;
-	__u64 closure;
 	__u32 header_length;	/* Length in bytes of following headers. */
 	__u32 header[0];
 };
 
+union fw_cdev_event {
+	struct fw_cdev_event_common common;
+	struct fw_cdev_event_bus_reset bus_reset;
+	struct fw_cdev_event_response response;
+	struct fw_cdev_event_request request;
+	struct fw_cdev_event_iso_interrupt iso_interrupt;
+};
+
 #define FW_CDEV_IOC_GET_INFO		_IO('#', 0x00)
 #define FW_CDEV_IOC_SEND_REQUEST	_IO('#', 0x01)
 #define FW_CDEV_IOC_ALLOCATE		_IO('#', 0x02)
@@ -145,8 +159,12 @@ struct fw_cdev_get_info {
 	__u64 rom;
 
 	/* If non-zero, a fw_cdev_event_bus_reset struct will be
-	 * copied here with the current state of the bus. */
+	 * copied here with the current state of the bus.  This does
+	 * not cause a bus reset to happen.  The value of closure in
+	 * this and sub-sequent bus reset events is set to
+	 * bus_reset_closure. */
 	__u64 bus_reset;
+	__u64 bus_reset_closure;
 
 	/* The index of the card this devices belongs to. */
 	__u32 card;
@@ -212,9 +230,9 @@ struct fw_cdev_iso_packet {
 };
 
 struct fw_cdev_queue_iso {
-	__u32 size;
 	__u64 packets;
 	__u64 data;
+	__u32 size;
 };
 
 struct fw_cdev_start_iso {