Message ID | 1436217097-31102-1-git-send-email-haiyangz@microsoft.com |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Haiyang Zhang <haiyangz@microsoft.com> Date: Mon, 6 Jul 2015 14:11:37 -0700 > When packet encapsulation is in use, the MTU needs to be reduced for > headroom reservation. > The existing code takes the updated MTU value only from the host side. > But vSwitch extensions, such as Open vSwitch, require the flexibility > to change the MTU to different values from within a guest during the > lifecycle of a vNIC, when the encapsulation protocol is changed. The > patch supports this kind of MTU changes. > > Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> > Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> Applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index dd45440..26cd14c 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -589,6 +589,7 @@ struct nvsp_message { #define NETVSC_MTU 65536 +#define NETVSC_MTU_MIN 68 #define NETVSC_RECEIVE_BUFFER_SIZE (1024*1024*16) /* 16MB */ #define NETVSC_RECEIVE_BUFFER_SIZE_LEGACY (1024*1024*15) /* 15MB */ diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 358475e..b855ba9 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -743,8 +743,7 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu) if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2) limit = NETVSC_MTU - ETH_HLEN; - /* Hyper-V hosts don't support MTU < ETH_DATA_LEN (1500) */ - if (mtu < ETH_DATA_LEN || mtu > limit) + if (mtu < NETVSC_MTU_MIN || mtu > limit) return -EINVAL; nvdev->start_remove = true; diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index 006c1b8..172824e 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -1053,7 +1053,7 @@ int rndis_filter_device_add(struct hv_device *dev, ret = rndis_filter_query_device(rndis_device, RNDIS_OID_GEN_MAXIMUM_FRAME_SIZE, &mtu, &size); - if (ret == 0 && size == sizeof(u32)) + if (ret == 0 && size == sizeof(u32) && mtu < net_device->ndev->mtu) net_device->ndev->mtu = mtu; /* Get the mac address */