hv_netvsc: Refactor assignments of struct netvsc_device_info

[ Upstream commit 7c9f335a3ff20557a92584199f3d35c7e992bbe5 ]

These assignments occur in multiple places. The patch refactor them
to a function for simplicity. It also puts the struct to heap area
for future expension.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
[sl: fix up subject line]
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 1c37a82..bece935 100644 (file)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -856,6 +856,36 @@ static void netvsc_get_channels(struct net_device *net,
        }
 }
 
+/* Alloc struct netvsc_device_info, and initialize it from either existing
+ * struct netvsc_device, or from default values.
+ */
+static struct netvsc_device_info *netvsc_devinfo_get
+                       (struct netvsc_device *nvdev)
+{
+       struct netvsc_device_info *dev_info;
+
+       dev_info = kzalloc(sizeof(*dev_info), GFP_ATOMIC);
+
+       if (!dev_info)
+               return NULL;
+
+       if (nvdev) {
+               dev_info->num_chn = nvdev->num_chn;
+               dev_info->send_sections = nvdev->send_section_cnt;
+               dev_info->send_section_size = nvdev->send_section_size;
+               dev_info->recv_sections = nvdev->recv_section_cnt;
+               dev_info->recv_section_size = nvdev->recv_section_size;
+       } else {
+               dev_info->num_chn = VRSS_CHANNEL_DEFAULT;
+               dev_info->send_sections = NETVSC_DEFAULT_TX;
+               dev_info->send_section_size = NETVSC_SEND_SECTION_SIZE;
+               dev_info->recv_sections = NETVSC_DEFAULT_RX;
+               dev_info->recv_section_size = NETVSC_RECV_SECTION_SIZE;
+       }
+
+       return dev_info;
+}
+
 static int netvsc_detach(struct net_device *ndev,
                         struct netvsc_device *nvdev)
 {
@@ -941,7 +971,7 @@ static int netvsc_set_channels(struct net_device *net,
        struct net_device_context *net_device_ctx = netdev_priv(net);
        struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
        unsigned int orig, count = channels->combined_count;
-       struct netvsc_device_info device_info;
+       struct netvsc_device_info *device_info;
        int ret;
 
        /* We do not support separate count for rx, tx, or other */
@@ -960,24 +990,26 @@ static int netvsc_set_channels(struct net_device *net,
 
        orig = nvdev->num_chn;
 
-       memset(&device_info, 0, sizeof(device_info));
-       device_info.num_chn = count;
-       device_info.send_sections = nvdev->send_section_cnt;
-       device_info.send_section_size = nvdev->send_section_size;
-       device_info.recv_sections = nvdev->recv_section_cnt;
-       device_info.recv_section_size = nvdev->recv_section_size;
+       device_info = netvsc_devinfo_get(nvdev);
+
+       if (!device_info)
+               return -ENOMEM;
+
+       device_info->num_chn = count;
 
        ret = netvsc_detach(net, nvdev);
        if (ret)
-               return ret;
+               goto out;
 
-       ret = netvsc_attach(net, &device_info);
+       ret = netvsc_attach(net, device_info);
        if (ret) {
-               device_info.num_chn = orig;
-               if (netvsc_attach(net, &device_info))
+               device_info->num_chn = orig;
+               if (netvsc_attach(net, device_info))
                        netdev_err(net, "restoring channel setting failed\n");
        }
 
+out:
+       kfree(device_info);
        return ret;
 }
 
@@ -1044,48 +1076,45 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
        struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
        struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
        int orig_mtu = ndev->mtu;
-       struct netvsc_device_info device_info;
+       struct netvsc_device_info *device_info;
        int ret = 0;
 
        if (!nvdev || nvdev->destroy)
                return -ENODEV;
 
+       device_info = netvsc_devinfo_get(nvdev);
+
+       if (!device_info)
+               return -ENOMEM;
+
        /* Change MTU of underlying VF netdev first. */
        if (vf_netdev) {
                ret = dev_set_mtu(vf_netdev, mtu);
                if (ret)
-                       return ret;
+                       goto out;
        }
 
-       memset(&device_info, 0, sizeof(device_info));
-       device_info.num_chn = nvdev->num_chn;
-       device_info.send_sections = nvdev->send_section_cnt;
-       device_info.send_section_size = nvdev->send_section_size;
-       device_info.recv_sections = nvdev->recv_section_cnt;
-       device_info.recv_section_size = nvdev->recv_section_size;
-
        ret = netvsc_detach(ndev, nvdev);
        if (ret)
                goto rollback_vf;
 
        ndev->mtu = mtu;
 
-       ret = netvsc_attach(ndev, &device_info);
-       if (ret)
-               goto rollback;
-
-       return 0;
+       ret = netvsc_attach(ndev, device_info);
+       if (!ret)
+               goto out;
 
-rollback:
        /* Attempt rollback to original MTU */
        ndev->mtu = orig_mtu;
 
-       if (netvsc_attach(ndev, &device_info))
+       if (netvsc_attach(ndev, device_info))
                netdev_err(ndev, "restoring mtu failed\n");
 rollback_vf:
        if (vf_netdev)
                dev_set_mtu(vf_netdev, orig_mtu);
 
+out:
+       kfree(device_info);
        return ret;
 }
 
@@ -1690,7 +1719,7 @@ static int netvsc_set_ringparam(struct net_device *ndev,
 {
        struct net_device_context *ndevctx = netdev_priv(ndev);
        struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
-       struct netvsc_device_info device_info;
+       struct netvsc_device_info *device_info;
        struct ethtool_ringparam orig;
        u32 new_tx, new_rx;
        int ret = 0;
@@ -1710,26 +1739,29 @@ static int netvsc_set_ringparam(struct net_device *ndev,
            new_rx == orig.rx_pending)
                return 0;        /* no change */
 
-       memset(&device_info, 0, sizeof(device_info));
-       device_info.num_chn = nvdev->num_chn;
-       device_info.send_sections = new_tx;
-       device_info.send_section_size = nvdev->send_section_size;
-       device_info.recv_sections = new_rx;
-       device_info.recv_section_size = nvdev->recv_section_size;
+       device_info = netvsc_devinfo_get(nvdev);
+
+       if (!device_info)
+               return -ENOMEM;
+
+       device_info->send_sections = new_tx;
+       device_info->recv_sections = new_rx;
 
        ret = netvsc_detach(ndev, nvdev);
        if (ret)
-               return ret;
+               goto out;
 
-       ret = netvsc_attach(ndev, &device_info);
+       ret = netvsc_attach(ndev, device_info);
        if (ret) {
-               device_info.send_sections = orig.tx_pending;
-               device_info.recv_sections = orig.rx_pending;
+               device_info->send_sections = orig.tx_pending;
+               device_info->recv_sections = orig.rx_pending;
 
-               if (netvsc_attach(ndev, &device_info))
+               if (netvsc_attach(ndev, device_info))
                        netdev_err(ndev, "restoring ringparam failed");
        }
 
+out:
+       kfree(device_info);
        return ret;
 }
 
@@ -2158,7 +2190,7 @@ static int netvsc_probe(struct hv_device *dev,
 {
        struct net_device *net = NULL;
        struct net_device_context *net_device_ctx;
-       struct netvsc_device_info device_info;
+       struct netvsc_device_info *device_info = NULL;
        struct netvsc_device *nvdev;
        int ret = -ENOMEM;
 
@@ -2205,21 +2237,21 @@ static int netvsc_probe(struct hv_device *dev,
        netif_set_real_num_rx_queues(net, 1);
 
        /* Notify the netvsc driver of the new device */
-       memset(&device_info, 0, sizeof(device_info));
-       device_info.num_chn = VRSS_CHANNEL_DEFAULT;
-       device_info.send_sections = NETVSC_DEFAULT_TX;
-       device_info.send_section_size = NETVSC_SEND_SECTION_SIZE;
-       device_info.recv_sections = NETVSC_DEFAULT_RX;
-       device_info.recv_section_size = NETVSC_RECV_SECTION_SIZE;
-
-       nvdev = rndis_filter_device_add(dev, &device_info);
+       device_info = netvsc_devinfo_get(NULL);
+
+       if (!device_info) {
+               ret = -ENOMEM;
+               goto devinfo_failed;
+       }
+
+       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);
                goto rndis_failed;
        }
 
-       memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
+       memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN);
 
        /* We must get rtnl lock before scheduling nvdev->subchan_work,
         * otherwise netvsc_subchan_work() can get rtnl lock first and wait
@@ -2257,12 +2289,16 @@ static int netvsc_probe(struct hv_device *dev,
 
        list_add(&net_device_ctx->list, &netvsc_dev_list);
        rtnl_unlock();
+
+       kfree(device_info);
        return 0;
 
 register_failed:
        rtnl_unlock();
        rndis_filter_device_remove(dev, nvdev);
 rndis_failed:
+       kfree(device_info);
+devinfo_failed:
        free_percpu(net_device_ctx->vf_stats);
 no_stats:
        hv_set_drvdata(dev, NULL);