Add fallback to get PF Name for AuxNetDevice

In case we fail to get Uplink Representor, fallback
to get PF PCI address and use sysfs to get PF netdevice.

This is needed in case a device supports the creation of
Auxiliary devices but is not in switchdev.

Signed-off-by: adrianc <[email protected]>

pkg/devices/gen_net.go

@@ -59,10 +59,11 @@ func NewGenNetDevice(deviceID string, dt types.DeviceType, isRdma bool) (*GenNet
 		}
 		netNames, _ = utils.GetNetNames(deviceID)
 	case types.AuxNetDeviceType:
-		if pfName, err = utils.GetSriovnetProvider().GetUplinkRepresentorFromAux(deviceID); err != nil {
+		if pfName, err = utils.GetPfNameFromAuxDev(deviceID); err != nil {
 			// AuxNetDeviceType by design should have PF, return error if failed to get PF name
 			return nil, err
 		}
+
 		if pfAddr, err = utils.GetSriovnetProvider().GetPfPciFromAux(deviceID); err != nil {
 			return nil, err
 		}

pkg/utils/utils.go

@@ -104,6 +104,30 @@ func GetPfName(pciAddr string) (string, error) {
 	return "", fmt.Errorf("the PF name is not found for device %s", pciAddr)
 }
 
+// GetPfNameFromAuxDev returns netdevice name of the PF associated with the
+// provided auxiliary device name.
+func GetPfNameFromAuxDev(auxDevName string) (string, error) {
+	pfName, err := GetSriovnetProvider().GetUplinkRepresentorFromAux(auxDevName)
+	if err != nil {
+		// fallback, try to get PF netdev name from PF PCI Address
+		pfAddr, err := GetSriovnetProvider().GetPfPciFromAux(auxDevName)
+		if err != nil {
+			return "", err
+		}
+		netdevs, err := GetNetNames(pfAddr)
+		if err != nil {
+			return "", err
+		}
+
+		if len(netdevs) == 0 {
+			return "", fmt.Errorf("no netdevs for PF address %s", pfAddr)
+		}
+
+		return netdevs[0], nil
+	}
+	return pfName, err
+}
+
 // IsSriovPF check if a pci device SRIOV capable given its pci address
 func IsSriovPF(pciAddr string) bool {
 	totalVfFilePath := filepath.Join(sysBusPci, pciAddr, totalVfFile)

pkg/utils/utils_test.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"errors"
 	"fmt"
 	"net"
 
@@ -596,4 +597,58 @@ var _ = Describe("In the utils package", func() {
 		Entry("wrong deviceID string layout (negative id number)", "driver_name.type.-4", ""),
 		Entry("valid deviceID string", "driver_name.type.123", "type"),
 	)
+
+	Context("GetPfNameFromAuxDev", func() {
+		var (
+			mockSriovnet *mocks.SriovnetProvider
+		)
+		BeforeEach(func() {
+			mockSriovnet = mocks.NewSriovnetProvider(GinkgoT())
+			SetSriovnetProviderInst(mockSriovnet)
+		})
+
+		It("Returns uplink representor netdev name if found", func() {
+			mockSriovnet.On("GetUplinkRepresentorFromAux", mock.AnythingOfType("string")).Return("enp3s0f0np0", nil)
+
+			pfName, err := GetPfNameFromAuxDev("mlx5_core.sf.4")
+			Expect(err).ToNot(HaveOccurred())
+			Expect(pfName).To(Equal("enp3s0f0np0"))
+		})
+
+		It("Returns PF netdev name from sysfs if uplink representor not found", func() {
+			mockSriovnet.On("GetUplinkRepresentorFromAux", mock.AnythingOfType("string")).Return("", errors.New("uplink not found"))
+			mockSriovnet.On("GetPfPciFromAux", mock.AnythingOfType("string")).Return("0000:03:00.0", nil)
+
+			fakeFs := &FakeFilesystem{
+				Dirs:  []string{"/sys/bus/pci/devices/0000:03:00.0/net"},
+				Files: map[string][]byte{"/sys/bus/pci/devices/0000:03:00.0/net/enp3s0f0np0": nil},
+			}
+			defer fakeFs.Use()()
+
+			pfName, err := GetPfNameFromAuxDev("mlx5_core.sf.4")
+			Expect(err).ToNot(HaveOccurred())
+			Expect(pfName).To(Equal("enp3s0f0np0"))
+		})
+
+		It("Fails if no uplink representor or PF netdev found", func() {
+			mockSriovnet.On("GetUplinkRepresentorFromAux", mock.AnythingOfType("string")).Return("", errors.New("uplink not found"))
+			mockSriovnet.On("GetPfPciFromAux", mock.AnythingOfType("string")).Return("0000:03:00.0", nil)
+
+			fakeFs := &FakeFilesystem{
+				Dirs: []string{"/sys/bus/pci/devices/0000:03:00.0"},
+			}
+			defer fakeFs.Use()()
+
+			_, err := GetPfNameFromAuxDev("mlx5_core.sf.4")
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("Fails if PF PCI not found", func() {
+			mockSriovnet.On("GetUplinkRepresentorFromAux", mock.AnythingOfType("string")).Return("", errors.New("uplink not found"))
+			mockSriovnet.On("GetPfPciFromAux", mock.AnythingOfType("string")).Return("", errors.New("PF PCI address not found"))
+
+			_, err := GetPfNameFromAuxDev("mlx5_core.sf.4")
+			Expect(err).To(HaveOccurred())
+		})
+	})
 })