Merge remote-tracking branches 'regulator/topic/anatop', 'regulator/topic/arizona...

[mirror_ubuntu-bionic-kernel.git] / drivers / net / virtio_net.c

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index ea9890d619670e1abfba75fe608c2925d824cb1c..f36584616e7d6825c7e69137b4a31a3d55779688 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -2230,14 +2230,8 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
 #define MIN_MTU ETH_MIN_MTU
 #define MAX_MTU ETH_MAX_MTU
 
-static int virtnet_probe(struct virtio_device *vdev)
+static int virtnet_validate(struct virtio_device *vdev)
 {
-       int i, err;
-       struct net_device *dev;
-       struct virtnet_info *vi;
-       u16 max_queue_pairs;
-       int mtu;
-
        if (!vdev->config->get) {
                dev_err(&vdev->dev, "%s failure: config access disabled\n",
                        __func__);
@@ -2247,6 +2241,25 @@ static int virtnet_probe(struct virtio_device *vdev)
        if (!virtnet_validate_features(vdev))
                return -EINVAL;
 
+       if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
+               int mtu = virtio_cread16(vdev,
+                                        offsetof(struct virtio_net_config,
+                                                 mtu));
+               if (mtu < MIN_MTU)
+                       __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
+       }
+
+       return 0;
+}
+
+static int virtnet_probe(struct virtio_device *vdev)
+{
+       int i, err;
+       struct net_device *dev;
+       struct virtnet_info *vi;
+       u16 max_queue_pairs;
+       int mtu;
+
        /* Find if host supports multiqueue virtio_net device */
        err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
                                   struct virtio_net_config,
@@ -2362,11 +2375,20 @@ static int virtnet_probe(struct virtio_device *vdev)
                                     offsetof(struct virtio_net_config,
                                              mtu));
                if (mtu < dev->min_mtu) {
-                       __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
-               } else {
-                       dev->mtu = mtu;
-                       dev->max_mtu = mtu;
+                       /* Should never trigger: MTU was previously validated
+                        * in virtnet_validate.
+                        */
+                       dev_err(&vdev->dev, "device MTU appears to have changed "
+                               "it is now %d < %d", mtu, dev->min_mtu);
+                       goto free_stats;
                }
+
+               dev->mtu = mtu;
+               dev->max_mtu = mtu;
+
+               /* TODO: size buffers correctly in this case. */
+               if (dev->mtu > ETH_DATA_LEN)
+                       vi->big_packets = true;
        }
 
        if (vi->any_header_sg)
@@ -2544,6 +2566,7 @@ static struct virtio_driver virtio_net_driver = {
        .driver.name =  KBUILD_MODNAME,
        .driver.owner = THIS_MODULE,
        .id_table =     id_table,
+       .validate =     virtnet_validate,
        .probe =        virtnet_probe,
        .remove =       virtnet_remove,
        .config_changed = virtnet_config_changed,