diff options
| -rw-r--r-- | drivers/net/virtio_net.c | 68 | ||||
| -rw-r--r-- | include/linux/virtio_net.h | 18 |
2 files changed, 83 insertions, 3 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index fe576e75a538..67bb583b7fc9 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -37,10 +37,12 @@ module_param(gso, bool, 0444); #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) #define GOOD_COPY_LEN 128 +#define VIRTNET_SEND_COMMAND_SG_MAX 0 + struct virtnet_info { struct virtio_device *vdev; - struct virtqueue *rvq, *svq; + struct virtqueue *rvq, *svq, *cvq; struct net_device *dev; struct napi_struct napi; unsigned int status; @@ -589,6 +591,53 @@ static int virtnet_open(struct net_device *dev) return 0; } +/* + * Send command via the control virtqueue and check status. Commands + * supported by the hypervisor, as indicated by feature bits, should + * never fail unless improperly formated. + */ +static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, + struct scatterlist *data, int out, int in) +{ + struct scatterlist sg[VIRTNET_SEND_COMMAND_SG_MAX + 2]; + struct virtio_net_ctrl_hdr ctrl; + virtio_net_ctrl_ack status = ~0; + unsigned int tmp; + + if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { + BUG(); /* Caller should know better */ + return false; + } + + BUG_ON(out + in > VIRTNET_SEND_COMMAND_SG_MAX); + + out++; /* Add header */ + in++; /* Add return status */ + + ctrl.class = class; + ctrl.cmd = cmd; + + sg_init_table(sg, out + in); + + sg_set_buf(&sg[0], &ctrl, sizeof(ctrl)); + memcpy(&sg[1], data, sizeof(struct scatterlist) * (out + in - 2)); + sg_set_buf(&sg[out + in - 1], &status, sizeof(status)); + + if (vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) != 0) + BUG(); + + vi->cvq->vq_ops->kick(vi->cvq); + + /* + * Spin for a response, the kick causes an ioport write, trapping + * into the hypervisor, so the request should be handled immediately. + */ + while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp)) + cpu_relax(); + + return status == VIRTIO_NET_OK; +} + static int virtnet_close(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); @@ -752,6 +801,14 @@ static int virtnet_probe(struct virtio_device *vdev) goto free_recv; } + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { + vi->cvq = vdev->config->find_vq(vdev, 2, NULL); + if (IS_ERR(vi->cvq)) { + err = PTR_ERR(vi->svq); + goto free_send; + } + } + /* Initialize our empty receive and send queues. */ skb_queue_head_init(&vi->recv); skb_queue_head_init(&vi->send); @@ -764,7 +821,7 @@ static int virtnet_probe(struct virtio_device *vdev) err = register_netdev(dev); if (err) { pr_debug("virtio_net: registering device failed\n"); - goto free_send; + goto free_ctrl; } /* Last of all, set up some receive buffers. */ @@ -784,6 +841,9 @@ static int virtnet_probe(struct virtio_device *vdev) unregister: unregister_netdev(dev); +free_ctrl: + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) + vdev->config->del_vq(vi->cvq); free_send: vdev->config->del_vq(vi->svq); free_recv: @@ -815,6 +875,8 @@ static void virtnet_remove(struct virtio_device *vdev) vdev->config->del_vq(vi->svq); vdev->config->del_vq(vi->rvq); + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) + vdev->config->del_vq(vi->cvq); unregister_netdev(vi->dev); while (vi->pages) @@ -834,7 +896,7 @@ static unsigned int features[] = { VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */ - VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, + VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, VIRTIO_F_NOTIFY_ON_EMPTY, }; diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index d8e362d52fd8..245eda829aa8 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -23,6 +23,7 @@ #define VIRTIO_NET_F_HOST_UFO 14 /* Host can handle UFO in. */ #define VIRTIO_NET_F_MRG_RXBUF 15 /* Host can merge receive buffers. */ #define VIRTIO_NET_F_STATUS 16 /* virtio_net_config.status available */ +#define VIRTIO_NET_F_CTRL_VQ 17 /* Control channel available */ #define VIRTIO_NET_S_LINK_UP 1 /* Link is up */ @@ -59,4 +60,21 @@ struct virtio_net_hdr_mrg_rxbuf { __u16 num_buffers; /* Number of merged rx buffers */ }; +/* + * Control virtqueue data structures + * + * The control virtqueue expects a header in the first sg entry + * and an ack/status response in the last entry. Data for the + * command goes in between. + */ +struct virtio_net_ctrl_hdr { + __u8 class; + __u8 cmd; +} __attribute__((packed)); + +typedef __u8 virtio_net_ctrl_ack; + +#define VIRTIO_NET_OK 0 +#define VIRTIO_NET_ERR 1 + #endif /* _LINUX_VIRTIO_NET_H */ |