From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:32791) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VgUk0-00031P-41 for qemu-devel@nongnu.org; Wed, 13 Nov 2013 02:20:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VgUjv-0008Ug-3y for qemu-devel@nongnu.org; Wed, 13 Nov 2013 02:19:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:15482) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VgUju-0008UU-S5 for qemu-devel@nongnu.org; Wed, 13 Nov 2013 02:19:51 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rAD7JmVG008248 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 13 Nov 2013 02:19:49 -0500 Message-ID: <52832808.4030604@redhat.com> Date: Wed, 13 Nov 2013 15:19:36 +0800 From: Jason Wang MIME-Version: 1.0 References: <1384141716-31034-1-git-send-email-akong@redhat.com> In-Reply-To: <1384141716-31034-1-git-send-email-akong@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] virtio-net: don't update mac_table in error state List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amos Kong , qemu-devel@nongnu.org Cc: vyasevic@redhat.com, stefanha@redhat.com, mst@redhat.com On 11/11/2013 11:48 AM, Amos Kong wrote: > mac_table was always cleaned up first in handling > VIRTIO_NET_CTRL_MAC_TABLE_SET command, and we din't recover > mac_table content in error state, it's not correct. > > This patch makes all the changes in temporal variables, > only update the real mac_table if everything is ok. > We won't change mac_table in error state, so rxfilter > notification isn't needed. > > This patch also fixed same problame in > http://lists.nongnu.org/archive/html/qemu-devel/2013-11/msg01188.html > (not merge) > > I will send patch for virtio spec to clarifying this change. > > Signed-off-by: Amos Kong Acked-by: Jason Wang In the future, maybe we can allocate the mac_table dynamically instead of embed it in VirtIONet. Then we can just does a pointer swap and gfree() and can save a memcpy() here. > --- > hw/net/virtio-net.c | 34 ++++++++++++++++++++-------------- > 1 file changed, 20 insertions(+), 14 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 22dbd05..880fa4a 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -610,11 +610,11 @@ static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd, > return VIRTIO_NET_ERR; > } > > - n->mac_table.in_use = 0; > - n->mac_table.first_multi = 0; > - n->mac_table.uni_overflow = 0; > - n->mac_table.multi_overflow = 0; > - memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN); > + int in_use = 0; > + int first_multi = 0; > + uint8_t uni_overflow = 0; > + uint8_t multi_overflow = 0; > + uint8_t *macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN); > > s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries, > sizeof(mac_data.entries)); > @@ -629,19 +629,19 @@ static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd, > } > > if (mac_data.entries <= MAC_TABLE_ENTRIES) { > - s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs, > + s = iov_to_buf(iov, iov_cnt, 0, macs, > mac_data.entries * ETH_ALEN); > if (s != mac_data.entries * ETH_ALEN) { > goto error; > } > - n->mac_table.in_use += mac_data.entries; > + in_use += mac_data.entries; > } else { > - n->mac_table.uni_overflow = 1; > + uni_overflow = 1; > } > > iov_discard_front(&iov, &iov_cnt, mac_data.entries * ETH_ALEN); > > - n->mac_table.first_multi = n->mac_table.in_use; > + first_multi = in_use; > > s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries, > sizeof(mac_data.entries)); > @@ -656,23 +656,29 @@ static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd, > goto error; > } > > - if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) { > - s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs, > + if (in_use + mac_data.entries <= MAC_TABLE_ENTRIES) { > + s = iov_to_buf(iov, iov_cnt, 0, &macs[in_use * ETH_ALEN], > mac_data.entries * ETH_ALEN); > if (s != mac_data.entries * ETH_ALEN) { > goto error; > } > - n->mac_table.in_use += mac_data.entries; > + in_use += mac_data.entries; > } else { > - n->mac_table.multi_overflow = 1; > + multi_overflow = 1; > } > > + n->mac_table.in_use = in_use; > + n->mac_table.first_multi = first_multi; > + n->mac_table.uni_overflow = uni_overflow; > + n->mac_table.multi_overflow = multi_overflow; > + memcpy(n->mac_table.macs, macs, MAC_TABLE_ENTRIES * ETH_ALEN); > + g_free(macs); > rxfilter_notify(nc); > > return VIRTIO_NET_OK; > > error: > - rxfilter_notify(nc); > + g_free(macs); > return VIRTIO_NET_ERR; > } >