From: Amos Kong <ak...@redhat.com> Currently we write MAC address to pci config space byte by byte, this means that we have an intermediate step where mac is wrong. This patch introduced a new control command to set MAC address, it's atomic.
VIRTIO_NET_F_CTRL_MAC_ADDR is a new feature bit for compatibility. Signed-off-by: Amos Kong <ak...@redhat.com> --- drivers/net/virtio_net.c | 21 ++++++++++++++++++++- include/uapi/linux/virtio_net.h | 8 +++++++- 2 files changed, 27 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 395ab4f..837c978 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -802,14 +802,32 @@ static int virtnet_set_mac_address(struct net_device *dev, void *p) struct virtnet_info *vi = netdev_priv(dev); struct virtio_device *vdev = vi->vdev; int ret; + struct scatterlist sg; + char save_addr[ETH_ALEN]; + unsigned char save_aatype; + + memcpy(save_addr, dev->dev_addr, ETH_ALEN); + save_aatype = dev->addr_assign_type; ret = eth_mac_addr(dev, p); if (ret) return ret; - if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) + if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { + sg_init_one(&sg, dev->dev_addr, dev->addr_len); + if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, + VIRTIO_NET_CTRL_MAC_ADDR_SET, + &sg, 1, 0)) { + dev_warn(&vdev->dev, + "Failed to set mac address by vq command.\n"); + memcpy(dev->dev_addr, save_addr, ETH_ALEN); + dev->addr_assign_type = save_aatype; + return -EINVAL; + } + } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { vdev->config->set(vdev, offsetof(struct virtio_net_config, mac), dev->dev_addr, dev->addr_len); + } return 0; } @@ -1627,6 +1645,7 @@ 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, }; static struct virtio_driver virtio_net_driver = { diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h index 848e358..a5a8c88 100644 --- a/include/uapi/linux/virtio_net.h +++ b/include/uapi/linux/virtio_net.h @@ -53,6 +53,7 @@ * network */ #define VIRTIO_NET_F_MQ 22 /* Device supports Receive Flow * Steering */ +#define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */ #define VIRTIO_NET_S_LINK_UP 1 /* Link is up */ #define VIRTIO_NET_S_ANNOUNCE 2 /* Announcement is needed */ @@ -127,7 +128,7 @@ typedef __u8 virtio_net_ctrl_ack; #define VIRTIO_NET_CTRL_RX_NOBCAST 5 /* - * Control the MAC filter table. + * Control the MAC * * The MAC filter table is managed by the hypervisor, the guest should * assume the size is infinite. Filtering should be considered @@ -140,6 +141,10 @@ typedef __u8 virtio_net_ctrl_ack; * first sg list contains unicast addresses, the second is for multicast. * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature * is available. + * + * The ADDR_SET command requests one out scatterlist, it contains a + * 6 bytes MAC address. This functionality is present if the + * VIRTIO_NET_F_CTRL_MAC_ADDR feature is available. */ struct virtio_net_ctrl_mac { __u32 entries; @@ -148,6 +153,7 @@ struct virtio_net_ctrl_mac { #define VIRTIO_NET_CTRL_MAC 1 #define VIRTIO_NET_CTRL_MAC_TABLE_SET 0 + #define VIRTIO_NET_CTRL_MAC_ADDR_SET 1 /* * Control VLAN filtering -- 1.7.11.7