[PATCH 4.18 101/135] hv_netvsc: pair VF based on serial number

Greg Kroah-Hartman
2018-10-16T17:14:59Z

From: Stephen Hemminger <stephen@networkplumber.org>

[ Upstream commit 00d7ddba1143623b31bc2c15d18216e2da031b14 ]

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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/hyperv/netvsc.c | 3 ++
drivers/net/hyperv/netvsc_drv.c | 58 ++++++++++++++++++++++------------------
2 files changed, 36 insertions(+), 25 deletions(-)

--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1203,6 +1203,9 @@ static void netvsc_send_vf(struct net_de

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,
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1794,20 +1794,6 @@ 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;
@@ -1936,26 +1922,48 @@ static void netvsc_vf_setup(struct work_
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;