From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH 1/2] macvtap: remove useless codes in macvtap_aio_read() and macvtap_recvmsg() Date: Fri, 06 Dec 2013 21:38:43 -0500 Message-ID: <52A28A33.4080306@gmail.com> References: <1386363300-19040-1-git-send-email-zwu.kernel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Zhi Yong Wu , Jason Wang To: Zhi Yong Wu , davem@davemloft.net Return-path: In-Reply-To: <1386363300-19040-1-git-send-email-zwu.kernel@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 12/06/2013 03:54 PM, Zhi Yong Wu wrote: > From: Zhi Yong Wu > > By checking related codes, it is impossible that ret > len or total_len, > so we should remove some useless coeds in both above functions. Looks like commit 6680ec68eff47d36f67b4351bc9836fd6cba9532 Author: Jason Wang Date: Thu Jul 25 13:00:33 2013 +0800 tuntap: hardware vlan tx support Introduced a change in tun_put_user() where we can never return a length longer then len or total_len. This has an effect that is now impossible to signal truncated status. It seems like a potential loss of functionality and it might make sense to restore it. -vlad > > Signed-off-by: Zhi Yong Wu > --- > drivers/net/macvtap.c | 5 ----- > 1 files changed, 0 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c > index 4c6f84c..7f4ccdd 100644 > --- a/drivers/net/macvtap.c > +++ b/drivers/net/macvtap.c > @@ -871,7 +871,6 @@ static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv, > } > > ret = macvtap_do_read(q, iv, len, file->f_flags & O_NONBLOCK); > - ret = min_t(ssize_t, ret, len); /* XXX copied from tun.c. Why? */ > out: > return ret; > } > @@ -1104,10 +1103,6 @@ static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock, > return -EINVAL; > ret = macvtap_do_read(q, m->msg_iov, total_len, > flags & MSG_DONTWAIT); > - if (ret > total_len) { > - m->msg_flags |= MSG_TRUNC; > - ret = flags & MSG_TRUNC ? ret : total_len; > - } > return ret; > } > >