/* Callback when data is received from userspace */
static int fcopy_on_msg(void *msg, int len)
{
int *val = (int *)msg;
if (len != sizeof(int))
return -EINVAL;
if (fcopy_transaction.state == HVUTIL_DEVICE_INIT)
return fcopy_handle_handshake(*val);
if (fcopy_transaction.state != HVUTIL_USERSPACE_REQ)
return -EINVAL;
/*
* Complete the transaction by forwarding the result
* to the host. But first, cancel the timeout.
*/
if (cancel_delayed_work_sync(&fcopy_timeout_work)) {
fcopy_transaction.state = HVUTIL_USERSPACE_RECV;
fcopy_respond_to_host(*val);
hv_poll_channel(fcopy_transaction.recv_channel,
fcopy_poll_wrapper);
}
return 0;
}
static ssize_t fcopy_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
int response = 0;
if (count != sizeof(int))
return -EINVAL;
if (copy_from_user(&response, buf, sizeof(int)))
return -EFAULT;
if (in_hand_shake) {
if (fcopy_handle_handshake(response))
return -EINVAL;
return sizeof(int);
}
/*
* Complete the transaction by forwarding the result
* to the host. But first, cancel the timeout.
*/
if (cancel_delayed_work_sync(&fcopy_work))
fcopy_respond_to_host(response);
return sizeof(int);
}