| Message ID | 1457620092-24170-3-git-send-email-aconole@redhat.com |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On Thu, 2016-03-10 at 09:28 -0500, Aaron Conole wrote: > This patch checks the feature bit for the VIRTIO_NET_F_MTU feature. If it > exists, read the advised MTU and use it. > > No proper error handling is provided for the case where a user changes the > negotiated MTU. A future commit will add proper error handling. Instead, a > warning is emitted if the guest changes the device MTU after previously being > given advice. > > Signed-off-by: Aaron Conole <aconole@redhat.com> > --- > drivers/net/virtio_net.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 767ab11..7175563 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -146,6 +146,7 @@ struct virtnet_info { > virtio_net_ctrl_ack ctrl_status; > u8 ctrl_promisc; > u8 ctrl_allmulti; > + bool negotiated_mtu; > }; > > struct padded_vnet_hdr { > @@ -1390,8 +1391,12 @@ static const struct ethtool_ops virtnet_ethtool_ops = { > > static int virtnet_change_mtu(struct net_device *dev, int new_mtu) > { > + struct virtnet_info *vi = netdev_priv(dev); > if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) > return -EINVAL; > + if (vi->negotiated_mtu == true) { why don't: if ((vi->negotiated_mtu == true) && (dev->mtu != new_mtu)) ? > + pr_warn("changing mtu from negotiated mtu."); > + } > dev->mtu = new_mtu; > return 0; > } > @@ -1836,6 +1841,13 @@ static int virtnet_probe(struct virtio_device *vdev) > if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) > vi->has_cvq = true; > > + if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) { > + vi->negotiated_mtu = true; > + dev->mtu = virtio_cread16(vdev, > + offsetof(struct virtio_net_config, > + mtu)); > + } > + > if (vi->any_header_sg) > dev->needed_headroom = vi->hdr_len; > > @@ -2017,8 +2029,9 @@ static unsigned int features[] = { > VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, > VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, > VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, > - VIRTIO_NET_F_CTRL_MAC_ADDR, > + VIRTIO_NET_F_CTRL_MAC_ADDR, Here a trailing white space slipped-in. Otherwise LGTM. Paolo > VIRTIO_F_ANY_LAYOUT, > + VIRTIO_NET_F_MTU, > }; > > static struct virtio_driver virtio_net_driver = {
Hello. On 03/10/2016 05:28 PM, Aaron Conole wrote: > This patch checks the feature bit for the VIRTIO_NET_F_MTU feature. If it > exists, read the advised MTU and use it. > > No proper error handling is provided for the case where a user changes the > negotiated MTU. A future commit will add proper error handling. Instead, a > warning is emitted if the guest changes the device MTU after previously being > given advice. > > Signed-off-by: Aaron Conole <aconole@redhat.com> > --- > drivers/net/virtio_net.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 767ab11..7175563 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c [...] > @@ -1390,8 +1391,12 @@ static const struct ethtool_ops virtnet_ethtool_ops = { > > static int virtnet_change_mtu(struct net_device *dev, int new_mtu) > { > + struct virtnet_info *vi = netdev_priv(dev); > if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) > return -EINVAL; > + if (vi->negotiated_mtu == true) { > + pr_warn("changing mtu from negotiated mtu."); > + } {} not needed, see Documentation/CodingStyle. [...] MBR, Sergei
Paolo Abeni <pabeni@redhat.com> writes: > On Thu, 2016-03-10 at 09:28 -0500, Aaron Conole wrote: >> This patch checks the feature bit for the VIRTIO_NET_F_MTU feature. If it >> exists, read the advised MTU and use it. >> >> No proper error handling is provided for the case where a user changes the >> negotiated MTU. A future commit will add proper error handling. Instead, a >> warning is emitted if the guest changes the device MTU after previously being >> given advice. >> >> Signed-off-by: Aaron Conole <aconole@redhat.com> >> --- >> drivers/net/virtio_net.c | 15 ++++++++++++++- >> 1 file changed, 14 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> index 767ab11..7175563 100644 >> --- a/drivers/net/virtio_net.c >> +++ b/drivers/net/virtio_net.c >> @@ -146,6 +146,7 @@ struct virtnet_info { >> virtio_net_ctrl_ack ctrl_status; >> u8 ctrl_promisc; >> u8 ctrl_allmulti; >> + bool negotiated_mtu; >> }; >> >> struct padded_vnet_hdr { >> @@ -1390,8 +1391,12 @@ static const struct ethtool_ops virtnet_ethtool_ops = { >> >> static int virtnet_change_mtu(struct net_device *dev, int new_mtu) >> { >> + struct virtnet_info *vi = netdev_priv(dev); >> if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) >> return -EINVAL; >> + if (vi->negotiated_mtu == true) { > > why don't: > > if ((vi->negotiated_mtu == true) && (dev->mtu != new_mtu)) > > ? Okay, I'll put this test in. >> + pr_warn("changing mtu from negotiated mtu."); >> + } >> dev->mtu = new_mtu; >> return 0; >> } >> @@ -1836,6 +1841,13 @@ static int virtnet_probe(struct virtio_device *vdev) >> if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) >> vi->has_cvq = true; >> >> + if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) { >> + vi->negotiated_mtu = true; >> + dev->mtu = virtio_cread16(vdev, >> + offsetof(struct virtio_net_config, >> + mtu)); >> + } >> + >> if (vi->any_header_sg) >> dev->needed_headroom = vi->hdr_len; >> >> @@ -2017,8 +2029,9 @@ static unsigned int features[] = { >> VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, >> VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, >> VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, >> - VIRTIO_NET_F_CTRL_MAC_ADDR, >> + VIRTIO_NET_F_CTRL_MAC_ADDR, > > Here a trailing white space slipped-in. > > Otherwise LGTM. > > Paolo D'oh! Okay, v2 will have this fixed. >> VIRTIO_F_ANY_LAYOUT, >> + VIRTIO_NET_F_MTU, >> }; >> >> static struct virtio_driver virtio_net_driver = { Thanks so much for the review, Paolo! -Aaron
Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> writes: > Hello. Hi Sergei, > On 03/10/2016 05:28 PM, Aaron Conole wrote: > >> This patch checks the feature bit for the VIRTIO_NET_F_MTU feature. If it >> exists, read the advised MTU and use it. >> >> No proper error handling is provided for the case where a user changes the >> negotiated MTU. A future commit will add proper error handling. Instead, a >> warning is emitted if the guest changes the device MTU after previously being >> given advice. >> >> Signed-off-by: Aaron Conole <aconole@redhat.com> >> --- >> drivers/net/virtio_net.c | 15 ++++++++++++++- >> 1 file changed, 14 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> index 767ab11..7175563 100644 >> --- a/drivers/net/virtio_net.c >> +++ b/drivers/net/virtio_net.c > [...] >> @@ -1390,8 +1391,12 @@ static const struct ethtool_ops virtnet_ethtool_ops = { >> >> static int virtnet_change_mtu(struct net_device *dev, int new_mtu) >> { >> + struct virtnet_info *vi = netdev_priv(dev); >> if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) >> return -EINVAL; >> + if (vi->negotiated_mtu == true) { >> + pr_warn("changing mtu from negotiated mtu."); >> + } > > {} not needed, see Documentation/CodingStyle. Okay, I'll make sure to fix this with v2. > [...] > > MBR, Sergei Thanks so much for the review! -Aaron
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 767ab11..7175563 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -146,6 +146,7 @@ struct virtnet_info { virtio_net_ctrl_ack ctrl_status; u8 ctrl_promisc; u8 ctrl_allmulti; + bool negotiated_mtu; }; struct padded_vnet_hdr { @@ -1390,8 +1391,12 @@ static const struct ethtool_ops virtnet_ethtool_ops = { static int virtnet_change_mtu(struct net_device *dev, int new_mtu) { + struct virtnet_info *vi = netdev_priv(dev); if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) return -EINVAL; + if (vi->negotiated_mtu == true) { + pr_warn("changing mtu from negotiated mtu."); + } dev->mtu = new_mtu; return 0; } @@ -1836,6 +1841,13 @@ static int virtnet_probe(struct virtio_device *vdev) if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) vi->has_cvq = true; + if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) { + vi->negotiated_mtu = true; + dev->mtu = virtio_cread16(vdev, + offsetof(struct virtio_net_config, + mtu)); + } + if (vi->any_header_sg) dev->needed_headroom = vi->hdr_len; @@ -2017,8 +2029,9 @@ static unsigned int features[] = { VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, - VIRTIO_NET_F_CTRL_MAC_ADDR, + VIRTIO_NET_F_CTRL_MAC_ADDR, VIRTIO_F_ANY_LAYOUT, + VIRTIO_NET_F_MTU, }; static struct virtio_driver virtio_net_driver = {
This patch checks the feature bit for the VIRTIO_NET_F_MTU feature. If it exists, read the advised MTU and use it. No proper error handling is provided for the case where a user changes the negotiated MTU. A future commit will add proper error handling. Instead, a warning is emitted if the guest changes the device MTU after previously being given advice. Signed-off-by: Aaron Conole <aconole@redhat.com> --- drivers/net/virtio_net.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)