From: Xin Xiaohui <xiaohui.xin@xxxxxxxxx> --- Michael, Thanks a lot for the explanation. I have drafted a patch for the qemu write after I looked into tun driver. Does it do in right way? Thanks Xiaohui drivers/vhost/mpassthru.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 45 insertions(+), 0 deletions(-) diff --git a/drivers/vhost/mpassthru.c b/drivers/vhost/mpassthru.c index e9449ac..1cde097 100644 --- a/drivers/vhost/mpassthru.c +++ b/drivers/vhost/mpassthru.c @@ -1065,6 +1065,49 @@ static unsigned int mp_chr_poll(struct file *file, poll_table * wait) return mask; } +static ssize_t mp_chr_aio_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long count, loff_t pos) +{ + struct file *file = iocb->ki_filp; + struct mp_struct *mp = mp_get(file->private_data); + struct sock *sk = mp->socket.sk; + struct sk_buff *skb; + int len, err; + ssize_t result; + + if (!mp) + return -EBADFD; + + /* currently, async is not supported */ + if (!is_sync_kiocb(iocb)) + return -EFAULT; + + len = iov_length(iov, count); + skb = sock_alloc_send_skb(sk, len + NET_IP_ALIGN, + file->f_flags & O_NONBLOCK, &err); + + if (!skb) + return -EFAULT; + + skb_reserve(skb, NET_IP_ALIGN); + skb_put(skb, len); + + if (skb_copy_datagram_from_iovec(skb, 0, iov, 0, len)) { + kfree_skb(skb); + return -EFAULT; + } + skb_set_network_header(skb, ETH_HLEN); + skb->protocol = *((__be16 *)(skb->data) + ETH_ALEN); + skb->dev = mp->dev; + + dev_queue_xmit(skb); + mp->dev->stats.tx_packets++; + mp->dev->stats.tx_bytes += len; + + mp_put(mp); + return result; +} + static int mp_chr_close(struct inode *inode, struct file *file) { struct mp_file *mfile = file->private_data; @@ -1084,6 +1127,8 @@ static int mp_chr_close(struct inode *inode, struct file *file) static const struct file_operations mp_fops = { .owner = THIS_MODULE, .llseek = no_llseek, + .write = do_sync_write, + .aio_write = mp_chr_aio_write, .poll = mp_chr_poll, .unlocked_ioctl = mp_chr_ioctl, .open = mp_chr_open, -- 1.5.4.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html