netvsc: add rtnl annotations in rndis

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

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 63c98bbbc596dbe11cc74ba71c384da02c5d763b..a164981c15f7a261eccbb29e85edf8d1c6c07309 100644 (file)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -69,7 +69,7 @@ static void netvsc_set_multicast_list(struct net_device *net)
 static int netvsc_open(struct net_device *net)
 {
        struct net_device_context *ndev_ctx = netdev_priv(net);
-       struct netvsc_device *nvdev = ndev_ctx->nvdev;
+       struct netvsc_device *nvdev = rtnl_dereference(ndev_ctx->nvdev);
        struct rndis_device *rdev;
        int ret = 0;
 
@@ -505,8 +505,8 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 
        /* timestamp packet in software */
        skb_tx_timestamp(skb);
-       ret = netvsc_send(net_device_ctx->device_ctx, packet,
-                         rndis_msg, &pb, skb);
+
+       ret = netvsc_send(net_device_ctx, packet, rndis_msg, &pb, skb);
        if (likely(ret == 0))
                return NETDEV_TX_OK;
 
@@ -717,6 +717,7 @@ static int netvsc_set_queues(struct net_device *net, struct hv_device *dev,
                             u32 num_chn)
 {
        struct netvsc_device_info device_info;
+       struct netvsc_device *net_device;
        int ret;
 
        memset(&device_info, 0, sizeof(device_info));
@@ -724,17 +725,16 @@ static int netvsc_set_queues(struct net_device *net, struct hv_device *dev,
        device_info.ring_size = ring_size;
        device_info.max_num_vrss_chns = num_chn;
 
-       ret = rndis_filter_device_add(dev, &device_info);
-       if (ret)
-               return ret;
-
        ret = netif_set_real_num_tx_queues(net, num_chn);
        if (ret)
                return ret;
 
        ret = netif_set_real_num_rx_queues(net, num_chn);
+       if (ret)
+               return ret;
 
-       return ret;
+       net_device = rndis_filter_device_add(dev, &device_info);
+       return IS_ERR(net_device) ? PTR_ERR(net_device) : 0;
 }
 
 static int netvsc_set_channels(struct net_device *net,
@@ -744,7 +744,7 @@ static int netvsc_set_channels(struct net_device *net,
        struct hv_device *dev = net_device_ctx->device_ctx;
        struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
        unsigned int count = channels->combined_count;
-       bool was_running;
+       bool was_opened;
        int ret;
 
        /* We do not support separate count for rx, tx, or other */
@@ -764,12 +764,9 @@ static int netvsc_set_channels(struct net_device *net,
        if (count > nvdev->max_chn)
                return -EINVAL;
 
-       was_running = netif_running(net);
-       if (was_running) {
-               ret = netvsc_close(net);
-               if (ret)
-                       return ret;
-       }
+       was_opened = rndis_filter_opened(nvdev);
+       if (was_opened)
+               rndis_filter_close(nvdev);
 
        rndis_filter_device_remove(dev, nvdev);
 
@@ -779,10 +776,12 @@ static int netvsc_set_channels(struct net_device *net,
        else
                netvsc_set_queues(net, dev, nvdev->num_chn);
 
-       if (was_running)
-               ret = netvsc_open(net);
+       nvdev = rtnl_dereference(net_device_ctx->nvdev);
+       if (was_opened)
+               rndis_filter_open(nvdev);
 
        /* We may have missed link change notifications */
+       net_device_ctx->last_reconfig = 0;
        schedule_delayed_work(&net_device_ctx->dwork, 0);
 
        return ret;
@@ -848,19 +847,18 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
        struct net_device_context *ndevctx = netdev_priv(ndev);
        struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
        struct hv_device *hdev = ndevctx->device_ctx;
+       int orig_mtu = ndev->mtu;
        struct netvsc_device_info device_info;
-       bool was_running;
+       bool was_opened;
        int ret = 0;
 
        if (!nvdev || nvdev->destroy)
                return -ENODEV;
 
-       was_running = netif_running(ndev);
-       if (was_running) {
-               ret = netvsc_close(ndev);
-               if (ret)
-                       return ret;
-       }
+       netif_device_detach(ndev);
+       was_opened = rndis_filter_opened(nvdev);
+       if (was_opened)
+               rndis_filter_close(nvdev);
 
        memset(&device_info, 0, sizeof(device_info));
        device_info.ring_size = ring_size;
@@ -869,18 +867,21 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 
        rndis_filter_device_remove(hdev, nvdev);
 
-       /* 'nvdev' has been freed in rndis_filter_device_remove() ->
-        * netvsc_device_remove () -> free_netvsc_device().
-        * We mustn't access it before it's re-created in
-        * rndis_filter_device_add() -> netvsc_device_add().
-        */
-
        ndev->mtu = mtu;
 
-       rndis_filter_device_add(hdev, &device_info);
+       nvdev = rndis_filter_device_add(hdev, &device_info);
+       if (IS_ERR(nvdev)) {
+               ret = PTR_ERR(nvdev);
+
+               /* Attempt rollback to original MTU */
+               ndev->mtu = orig_mtu;
+               rndis_filter_device_add(hdev, &device_info);
+       }
+
+       if (was_opened)
+               rndis_filter_open(nvdev);
 
-       if (was_running)
-               ret = netvsc_open(ndev);
+       netif_device_attach(ndev);
 
        /* We may have missed link change notifications */
        schedule_delayed_work(&ndevctx->dwork, 0);
@@ -1363,7 +1364,7 @@ static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
                        continue;       /* not a netvsc device */
 
                net_device_ctx = netdev_priv(dev);
-               if (net_device_ctx->nvdev == NULL)
+               if (!rtnl_dereference(net_device_ctx->nvdev))
                        continue;       /* device is removed */
 
                if (rtnl_dereference(net_device_ctx->vf_netdev) == vf_netdev)
@@ -1528,8 +1529,10 @@ static int netvsc_probe(struct hv_device *dev,
        memset(&device_info, 0, sizeof(device_info));
        device_info.ring_size = ring_size;
        device_info.num_chn = VRSS_CHANNEL_DEFAULT;
-       ret = rndis_filter_device_add(dev, &device_info);
-       if (ret != 0) {
+
+       nvdev = rndis_filter_device_add(dev, &device_info);
+       if (IS_ERR(nvdev)) {
+               ret = PTR_ERR(nvdev);
                netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
                free_netdev(net);
                hv_set_drvdata(dev, NULL);
@@ -1543,10 +1546,11 @@ static int netvsc_probe(struct hv_device *dev,
                NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
        net->vlan_features = net->features;
 
-       /* RCU not necessary here, device not registered */
-       nvdev = net_device_ctx->nvdev;
        netif_set_real_num_tx_queues(net, nvdev->num_chn);
        netif_set_real_num_rx_queues(net, nvdev->num_chn);
+       rtnl_unlock();
+
+       netdev_lockdep_set_classes(net);
 
        /* MTU range: 68 - 1500 or 65521 */
        net->min_mtu = NETVSC_MTU_MIN;
@@ -1588,7 +1592,8 @@ static int netvsc_remove(struct hv_device *dev)
         * removed. Also blocks mtu and channel changes.
         */
        rtnl_lock();
-       rndis_filter_device_remove(dev, ndev_ctx->nvdev);
+       rndis_filter_device_remove(dev,
+                                  rtnl_dereference(ndev_ctx->nvdev));
        rtnl_unlock();
 
        unregister_netdev(net);