firewire: implement asynchronous stream transmission

Allow userspace and other firewire drivers (fw-ipv4 I'm looking at
you!) to send Asynchronous Transmit Streams as described in 7.8.3 of
release 1.1 of the 1394 Open Host Controller Interface Specification.

Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (tweaks)

1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/firewire/fw-cdev.c b/drivers/firewire/fw-cdev.c
index 214e534efee5..539dae5eb5b2 100644
--- a/drivers/firewire/fw-cdev.c
+++ b/drivers/firewire/fw-cdev.c
@@ -1242,6 +1242,38 @@ static int ioctl_send_broadcast_request(struct client *client, void *buffer)
         return init_request(client, request, LOCAL_BUS | 0x3f, SCODE_100);
 }
 
+struct stream_packet {
+        struct fw_packet packet;
+        u8 data[0];
+};
+
+static void send_stream_packet_done(struct fw_packet *packet,
+                                    struct fw_card *card, int status)
+{
+        kfree(container_of(packet, struct stream_packet, packet));
+}
+
+static int ioctl_send_stream_packet(struct client *client, void *buffer)
+{
+        struct fw_cdev_send_stream_packet *request = buffer;
+        struct stream_packet *p;
+
+        p = kmalloc(sizeof(*p) + request->size, GFP_KERNEL);
+        if (p == NULL)
+                return -ENOMEM;
+
+        if (request->data &&
+            copy_from_user(p->data, u64_to_uptr(request->data), request->size)) {
+                kfree(p);
+                return -EFAULT;
+        }
+        fw_send_stream_packet(client->device->card, &p->packet,
+                              request->generation, request->speed,
+                              request->channel, request->sy, request->tag,
+                              p->data, request->size, send_stream_packet_done);
+        return 0;
+}
+
 static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
         ioctl_get_info,
         ioctl_send_request,
@@ -1262,6 +1294,7 @@ static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
         ioctl_deallocate_iso_resource_once,
         ioctl_get_speed,
         ioctl_send_broadcast_request,
+        ioctl_send_stream_packet,
 };
 
 static int dispatch_ioctl(struct client *client,