Re: [PATCH V2 net-next 6/7] tap: support receiving skb from msg_control

[Jason Wang]

On 2017å03æ30æ 23:03, Michael S. Tsirkin wrote:
> On Thu, Mar 30, 2017 at 03:22:29PM +0800, Jason Wang wrote:
> > This patch makes tap_recvmsg() can receive from skb from its caller
> > through msg_control. Vhost_net will be the first user.
> >
> > Signed-off-by: Jason Wang<jasowang@xxxxxxxxxx>
> > ---
> >   drivers/net/tap.c | 12 ++++++++----
> >   1 file changed, 8 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/net/tap.c b/drivers/net/tap.c
> > index abdaf86..07d9174 100644
> > --- a/drivers/net/tap.c
> > +++ b/drivers/net/tap.c
> > @@ -824,15 +824,17 @@ static ssize_t tap_put_user(struct tap_queue *q,
> >   
> >   static ssize_t tap_do_read(struct tap_queue *q,
> >   			   struct iov_iter *to,
> > -			   int noblock)
> > +			   int noblock, struct sk_buff *skb)
> >   {
> >   	DEFINE_WAIT(wait);
> > -	struct sk_buff *skb;
> >   	ssize_t ret = 0;
> >   
> >   	if (!iov_iter_count(to))
> >   		return 0;
> >   
> > +	if (skb)
> > +		goto done;
> > +
> >   	while (1) {
> >   		if (!noblock)
> >   			prepare_to_wait(sk_sleep(&q->sk), &wait,
> > @@ -856,6 +858,7 @@ static ssize_t tap_do_read(struct tap_queue *q,
> >   	if (!noblock)
> >   		finish_wait(sk_sleep(&q->sk), &wait);
> >   
> > +done:
> Please just use an if {} block here. goto on error is ok,
> but we are far from done here and goto done is misleading.

Ok.

Thanks.