hv_netvsc: pair VF based on serial number

Matching network device based on MAC address is problematic
since a non VF network device can be creted with a duplicate MAC
address causing confusion and problems.  The VMBus API does provide
a serial number that is a better matching method.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 31c3d77..fe01e14 100644 (file)
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1203,6 +1203,9 @@ static void netvsc_send_vf(struct net_device *ndev,
 
        net_device_ctx->vf_alloc = nvmsg->msg.v4_msg.vf_assoc.allocated;
        net_device_ctx->vf_serial = nvmsg->msg.v4_msg.vf_assoc.serial;
+       netdev_info(ndev, "VF slot %u %s\n",
+                   net_device_ctx->vf_serial,
+                   net_device_ctx->vf_alloc ? "added" : "removed");
 }
 
 static  void netvsc_receive_inband(struct net_device *ndev,

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 915fbd6..3af6d8d 100644 (file)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1894,20 +1894,6 @@ out_unlock:
        rtnl_unlock();
 }
 
-static struct net_device *get_netvsc_bymac(const u8 *mac)
-{
-       struct net_device_context *ndev_ctx;
-
-       list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
-               struct net_device *dev = hv_get_drvdata(ndev_ctx->device_ctx);
-
-               if (ether_addr_equal(mac, dev->perm_addr))
-                       return dev;
-       }
-
-       return NULL;
-}
-
 static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
 {
        struct net_device_context *net_device_ctx;
@@ -2036,26 +2022,48 @@ static void netvsc_vf_setup(struct work_struct *w)
        rtnl_unlock();
 }
 
+/* Find netvsc by VMBus serial number.
+ * The PCI hyperv controller records the serial number as the slot.
+ */
+static struct net_device *get_netvsc_byslot(const struct net_device *vf_netdev)
+{
+       struct device *parent = vf_netdev->dev.parent;
+       struct net_device_context *ndev_ctx;
+       struct pci_dev *pdev;
+
+       if (!parent || !dev_is_pci(parent))
+               return NULL; /* not a PCI device */
+
+       pdev = to_pci_dev(parent);
+       if (!pdev->slot) {
+               netdev_notice(vf_netdev, "no PCI slot information\n");
+               return NULL;
+       }
+
+       list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
+               if (!ndev_ctx->vf_alloc)
+                       continue;
+
+               if (ndev_ctx->vf_serial == pdev->slot->number)
+                       return hv_get_drvdata(ndev_ctx->device_ctx);
+       }
+
+       netdev_notice(vf_netdev,
+                     "no netdev found for slot %u\n", pdev->slot->number);
+       return NULL;
+}
+
 static int netvsc_register_vf(struct net_device *vf_netdev)
 {
-       struct net_device *ndev;
        struct net_device_context *net_device_ctx;
-       struct device *pdev = vf_netdev->dev.parent;
        struct netvsc_device *netvsc_dev;
+       struct net_device *ndev;
        int ret;
 
        if (vf_netdev->addr_len != ETH_ALEN)
                return NOTIFY_DONE;
 
-       if (!pdev || !dev_is_pci(pdev) || dev_is_pf(pdev))
-               return NOTIFY_DONE;
-
-       /*
-        * We will use the MAC address to locate the synthetic interface to
-        * associate with the VF interface. If we don't find a matching
-        * synthetic interface, move on.
-        */
-       ndev = get_netvsc_bymac(vf_netdev->perm_addr);
+       ndev = get_netvsc_byslot(vf_netdev);
        if (!ndev)
                return NOTIFY_DONE;