/*
 * WiMAX stack operation: relay a message from user space
 *
 * @wimax_dev: device descriptor
 * @pipe_name: named pipe the message is for
 * @msg_buf: pointer to the message bytes
 * @msg_len: length of the buffer
 * @genl_info: passed by the generic netlink layer
 *
 * The WiMAX stack will call this function when a message was received
 * from user space.
 *
 * For the i2400m, this is an L3L4 message, as specified in
 * include/linux/wimax/i2400m.h, and thus prefixed with a 'struct
 * i2400m_l3l4_hdr'. Driver (and device) expect the messages to be
 * coded in Little Endian.
 *
 * This function just verifies that the header declaration and the
 * payload are consistent and then deals with it, either forwarding it
 * to the device or procesing it locally.
 *
 * In the i2400m, messages are basically commands that will carry an
 * ack, so we use i2400m_msg_to_dev() and then deliver the ack back to
 * user space. The rx.c code might intercept the response and use it
 * to update the driver's state, but then it will pass it on so it can
 * be relayed back to user space.
 *
 * Note that asynchronous events from the device are processed and
 * sent to user space in rx.c.
 */
static
int i2400m_op_msg_from_user(struct wimax_dev *wimax_dev,
			    const char *pipe_name,
			    const void *msg_buf, size_t msg_len,
			    const struct genl_info *genl_info)
{
	int result;
	struct i2400m *i2400m = wimax_dev_to_i2400m(wimax_dev);
	struct device *dev = i2400m_dev(i2400m);
	struct sk_buff *ack_skb;

	d_fnstart(4, dev, "(wimax_dev %p [i2400m %p] msg_buf %p "
		  "msg_len %zu genl_info %p)\n", wimax_dev, i2400m,
		  msg_buf, msg_len, genl_info);
	ack_skb = i2400m_msg_to_dev(i2400m, msg_buf, msg_len);
	result = PTR_ERR(ack_skb);
	if (IS_ERR(ack_skb))
		goto error_msg_to_dev;
	result = wimax_msg_send(&i2400m->wimax_dev, ack_skb);
error_msg_to_dev:
	d_fnend(4, dev, "(wimax_dev %p [i2400m %p] msg_buf %p msg_len %zu "
		"genl_info %p) = %d\n", wimax_dev, i2400m, msg_buf, msg_len,
		genl_info, result);
	return result;
}
int wimax_msg(struct wimax_dev *wimax_dev, const char *pipe_name,
	      const void *buf, size_t size, gfp_t gfp_flags)
{
	int result = -ENOMEM;
	struct sk_buff *skb;

	skb = wimax_msg_alloc(wimax_dev, pipe_name, buf, size, gfp_flags);
	if (IS_ERR(skb))
		result = PTR_ERR(skb);
	else
		result = wimax_msg_send(wimax_dev, skb);
	return result;
}