vfio: make vfio run on s390

add Kconfig switch to hide INTx
add Kconfig switch to let vfio announce PCI BARs are not mapable

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/Kconfig

@@ -16,7 +16,7 @@ config VFIO_SPAPR_EEH
 menuconfig VFIO
 	tristate "VFIO Non-Privileged userspace driver framework"
 	depends on IOMMU_API
-	select VFIO_IOMMU_TYPE1 if X86
+	select VFIO_IOMMU_TYPE1 if (X86 || S390)
 	select VFIO_IOMMU_SPAPR_TCE if (PPC_POWERNV || PPC_PSERIES)
 	select VFIO_SPAPR_EEH if (PPC_POWERNV || PPC_PSERIES)
 	select ANON_INODES

drivers/vfio/pci/Kconfig

@@ -16,3 +16,11 @@ config VFIO_PCI_VGA
 	  BIOS and generic video drivers.
 
 	  If you don't know what to do here, say N.
+
+config VFIO_PCI_MMAP
+	depends on VFIO_PCI
+	def_bool y if !S390
+
+config VFIO_PCI_INTX
+	depends on VFIO_PCI
+	def_bool y if !S390

drivers/vfio/pci/vfio_pci.c

@@ -215,7 +215,7 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
 	if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
 		u8 pin;
 		pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
-		if (pin)
+		if (IS_ENABLED(CONFIG_VFIO_PCI_INTX) && pin)
 			return 1;
 
 	} else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
@@ -406,7 +406,8 @@ static long vfio_pci_ioctl(void *device_data,
 
 			info.flags = VFIO_REGION_INFO_FLAG_READ |
 				     VFIO_REGION_INFO_FLAG_WRITE;
-			if (pci_resource_flags(pdev, info.index) &
+			if (IS_ENABLED(CONFIG_VFIO_PCI_MMAP) &&
+			    pci_resource_flags(pdev, info.index) &
 			    IORESOURCE_MEM && info.size >= PAGE_SIZE)
 				info.flags |= VFIO_REGION_INFO_FLAG_MMAP;
 			break;

drivers/vfio/pci/vfio_pci_config.c

@@ -609,6 +609,10 @@ static int __init init_pci_cap_basic_perm(struct perm_bits *perm)
 
 	/* Sometimes used by sw, just virtualize */
 	p_setb(perm, PCI_INTERRUPT_LINE, (u8)ALL_VIRT, (u8)ALL_WRITE);
+
+	/* Virtualize interrupt pin to allow hiding INTx */
+	p_setb(perm, PCI_INTERRUPT_PIN, (u8)ALL_VIRT, (u8)NO_WRITE);
+
 	return 0;
 }
 
@@ -1445,6 +1449,9 @@ int vfio_config_init(struct vfio_pci_device *vdev)
 		*(__le16 *)&vconfig[PCI_DEVICE_ID] = cpu_to_le16(pdev->device);
 	}
 
+	if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX))
+		vconfig[PCI_INTERRUPT_PIN] = 0;
+
 	ret = vfio_cap_init(vdev);
 	if (ret)
 		goto out;