KVM: enable PCI multiple-segments for pass-through device

Enable optional parameter (default 0) - PCI segment (or domain) besides
BDF, when assigning PCI device to guest.

Signed-off-by: Zhai Edwin <edwin.zhai@intel.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

arch/x86/kvm/x86.c

@@ -1569,6 +1569,7 @@ int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_HYPERV:
 	case KVM_CAP_HYPERV_VAPIC:
 	case KVM_CAP_HYPERV_SPIN:
+	case KVM_CAP_PCI_SEGMENT:
 		r = 1;
 		break;
 	case KVM_CAP_COALESCED_MMIO:

include/linux/kvm.h

@@ -500,6 +500,7 @@ struct kvm_ioeventfd {
 #define KVM_CAP_HYPERV 44
 #define KVM_CAP_HYPERV_VAPIC 45
 #define KVM_CAP_HYPERV_SPIN 46
+#define KVM_CAP_PCI_SEGMENT 47
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
@@ -694,8 +695,9 @@ struct kvm_assigned_pci_dev {
 	__u32 busnr;
 	__u32 devfn;
 	__u32 flags;
+	__u32 segnr;
 	union {
-		__u32 reserved[12];
+		__u32 reserved[11];
 	};
 };
 

include/linux/kvm_host.h

@@ -400,6 +400,7 @@ struct kvm_assigned_dev_kernel {
 	struct work_struct interrupt_work;
 	struct list_head list;
 	int assigned_dev_id;
+	int host_segnr;
 	int host_busnr;
 	int host_devfn;
 	unsigned int entries_nr;

virt/kvm/assigned-dev.c

@@ -526,7 +526,8 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 		r = -ENOMEM;
 		goto out;
 	}
-	dev = pci_get_bus_and_slot(assigned_dev->busnr,
+	dev = pci_get_domain_bus_and_slot(assigned_dev->segnr,
+				   assigned_dev->busnr,
 				   assigned_dev->devfn);
 	if (!dev) {
 		printk(KERN_INFO "%s: host device not found\n", __func__);
@@ -548,6 +549,7 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 	pci_reset_function(dev);
 
 	match->assigned_dev_id = assigned_dev->assigned_dev_id;
+	match->host_segnr = assigned_dev->segnr;
 	match->host_busnr = assigned_dev->busnr;
 	match->host_devfn = assigned_dev->devfn;
 	match->flags = assigned_dev->flags;

virt/kvm/iommu.c

@@ -106,7 +106,8 @@ int kvm_assign_device(struct kvm *kvm,
 
 	r = iommu_attach_device(domain, &pdev->dev);
 	if (r) {
-		printk(KERN_ERR "assign device %x:%x.%x failed",
+		printk(KERN_ERR "assign device %x:%x:%x.%x failed",
+			pci_domain_nr(pdev->bus),
 			pdev->bus->number,
 			PCI_SLOT(pdev->devfn),
 			PCI_FUNC(pdev->devfn));
@@ -127,7 +128,8 @@ int kvm_assign_device(struct kvm *kvm,
 			goto out_unmap;
 	}
 
-	printk(KERN_DEBUG "assign device: host bdf = %x:%x:%x\n",
+	printk(KERN_DEBUG "assign device %x:%x:%x.%x\n",
+		assigned_dev->host_segnr,
 		assigned_dev->host_busnr,
 		PCI_SLOT(assigned_dev->host_devfn),
 		PCI_FUNC(assigned_dev->host_devfn));
@@ -154,7 +156,8 @@ int kvm_deassign_device(struct kvm *kvm,
 
 	iommu_detach_device(domain, &pdev->dev);
 
-	printk(KERN_DEBUG "deassign device: host bdf = %x:%x:%x\n",
+	printk(KERN_DEBUG "deassign device %x:%x:%x.%x\n",
+		assigned_dev->host_segnr,
 		assigned_dev->host_busnr,
 		PCI_SLOT(assigned_dev->host_devfn),
 		PCI_FUNC(assigned_dev->host_devfn));