[RFC PATCH] virtio-net: introduce a new macaddr control

akong
2013-01-10T14:51:57Z

From: Amos Kong <akong@redhat.com>

In virtio-net guest driver, 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 in one time.

VIRTIO_NET_F_CTRL_MAC_ADDR is a new feature bit for compatibility.

Signed-off-by: Amos Kong <akong@redhat.com>
---
hw/virtio-net.c | 9 +++++++++
hw/virtio-net.h | 9 ++++++++-
2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index dc7c6d6..fc11106 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -247,6 +247,7 @@ static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
VirtIONet *n = to_virtio_net(vdev);

features |= (1 << VIRTIO_NET_F_MAC);
+ features |= (1 << VIRTIO_NET_F_CTRL_MAC_ADDR);

if (!peer_has_vnet_hdr(n)) {
features &= ~(0x1 << VIRTIO_NET_F_CSUM);
@@ -282,6 +283,7 @@ static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
/* Linux kernel 2.6.25. It understood MAC (as everyone must),
* but also these: */
features |= (1 << VIRTIO_NET_F_MAC);
+ features |= (1 << VIRTIO_NET_F_CTRL_MAC_ADDR);
features |= (1 << VIRTIO_NET_F_CSUM);
features |= (1 << VIRTIO_NET_F_HOST_TSO4);
features |= (1 << VIRTIO_NET_F_HOST_TSO6);
@@ -349,6 +351,13 @@ static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
{
struct virtio_net_ctrl_mac mac_data;

+ if (cmd == VIRTIO_NET_CTRL_MAC_ADDR_SET && elem->out_num == 2) {
+ /* Set MAC address */
+ memcpy(n->mac, elem->out_sg[1].iov_base, elem->out_sg[1].iov_len);
+ qemu_format_nic_info_str(&n->nic->nc, n->mac);
+ return VIRTIO_NET_OK;
+ }
+
if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
elem->out_sg[1].iov_len < sizeof(mac_data) ||
elem->out_sg[2].iov_len < sizeof(mac_data))
diff --git a/hw/virtio-net.h b/hw/virtio-net.h
index d46fb98..9394cc0 100644
--- a/hw/virtio-net.h
+++ b/hw/virtio-net.h
@@ -44,6 +44,8 @@
#define VIRTIO_NET_F_CTRL_VLAN 19 /* Control channel VLAN filtering */
#define VIRTIO_NET_F_CTRL_RX_EXTRA 20 /* Extra RX mode control support */

+#define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */
+
#define VIRTIO_NET_S_LINK_UP 1 /* Link is up */

#define TX_TIMER_INTERVAL 150000 /* 150 us */
@@ -106,7 +108,7 @@ typedef uint8_t virtio_net_ctrl_ack;
#define VIRTIO_NET_CTRL_RX_MODE_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
@@ -119,6 +121,10 @@ typedef uint8_t 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 {
uint32_t entries;
@@ -126,6 +132,7 @@ 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