PCI/IOV: Add pci_vf_drivers_autoprobe() interface

Add a pci_vf_drivers_autoprobe() interface. Setting autoprobe to false
on the PF prevents drivers from binding to VFs when they are enabled.
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Signed-off-by: Juan J. Alvarez <jjalvare@linux.vnet.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/pseries/pci.c

@@ -63,6 +63,7 @@ int pseries_pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
 {
 	/* Allocate PCI data */
 	add_dev_pci_data(pdev);
+	pci_vf_drivers_autoprobe(pdev, false);
 	return 0;
 }
 
@@ -70,6 +71,7 @@ int pseries_pcibios_sriov_disable(struct pci_dev *pdev)
 {
 	/* Release PCI data */
 	remove_dev_pci_data(pdev);
+	pci_vf_drivers_autoprobe(pdev, true);
 	return 0;
 }
 #endif

drivers/pci/iov.c

@@ -635,6 +635,17 @@ void pci_restore_iov_state(struct pci_dev *dev)
 		sriov_restore_state(dev);
 }
 
+/**
+ * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
+ * @dev: the PCI device
+ * @auto_probe: set VF drivers auto probe flag
+ */
+void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
+{
+	if (dev->is_physfn)
+		dev->sriov->drivers_autoprobe = auto_probe;
+}
+
 /**
  * pci_iov_bus_range - find bus range used by Virtual Function
  * @bus: the PCI bus

include/linux/pci.h

@@ -1961,6 +1961,7 @@ int pci_vfs_assigned(struct pci_dev *dev);
 int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs);
 int pci_sriov_get_totalvfs(struct pci_dev *dev);
 resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno);
+void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool probe);
 #else
 static inline int pci_iov_virtfn_bus(struct pci_dev *dev, int id)
 {
@@ -1988,6 +1989,7 @@ static inline int pci_sriov_get_totalvfs(struct pci_dev *dev)
 { return 0; }
 static inline resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
 { return 0; }
+static inline void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool probe) { }
 #endif
 
 #if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)