2 files changed, 25 insertions, 20 deletions

diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index c4bb261c..b1805b7 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -65,21 +65,13 @@ pcibios_align_resource(void *data, const struct resource *res,
 			resource_size_t size, resource_size_t align)
 {
 	struct pci_dev *dev = data;
-	resource_size_t start = round_down(res->end - size + 1, align);
+	resource_size_t start = res->start;
 
 	if (res->flags & IORESOURCE_IO) {
-
-		/*
-		 * If we're avoiding ISA aliases, the largest contiguous I/O
-		 * port space is 256 bytes.  Clearing bits 9 and 10 preserves
-		 * all 256-byte and smaller alignments, so the result will
-		 * still be correctly aligned.
-		 */
-		if (!skip_isa_ioresource_align(dev))
-			start &= ~0x300;
-	} else if (res->flags & IORESOURCE_MEM) {
-		if (start < BIOS_END)
-			start = res->end;	/* fail; no space */
+		if (skip_isa_ioresource_align(dev))
+			return start;
+		if (start & 0x300)
+			start = (start + 0x3ff) & ~0x3ff;
 	}
 	return start;
 }
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index d7b5109..25cd4a0 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -70,6 +70,9 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
 struct xen_pci_frontend_ops *xen_pci_frontend;
 EXPORT_SYMBOL_GPL(xen_pci_frontend);
 
+#define XEN_PIRQ_MSI_DATA  (MSI_DATA_TRIGGER_EDGE | \
+		MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0))
+
 static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
 		struct msi_msg *msg)
 {
@@ -83,12 +86,7 @@ static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
 		MSI_ADDR_REDIRECTION_CPU |
 		MSI_ADDR_DEST_ID(pirq);
 
-	msg->data =
-		MSI_DATA_TRIGGER_EDGE |
-		MSI_DATA_LEVEL_ASSERT |
-		/* delivery mode reserved */
-		(3 << 8) |
-		MSI_DATA_VECTOR(0);
+	msg->data = XEN_PIRQ_MSI_DATA;
 }
 
 static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
@@ -98,8 +96,23 @@ static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 	struct msi_msg msg;
 
 	list_for_each_entry(msidesc, &dev->msi_list, list) {
+		__read_msi_msg(msidesc, &msg);
+		pirq = MSI_ADDR_EXT_DEST_ID(msg.address_hi) |
+			((msg.address_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xff);
+		if (xen_irq_from_pirq(pirq) >= 0 && msg.data == XEN_PIRQ_MSI_DATA) {
+			xen_allocate_pirq_msi((type == PCI_CAP_ID_MSIX) ?
+					"msi-x" : "msi", &irq, &pirq, XEN_ALLOC_IRQ);
+			if (irq < 0)
+				goto error;
+			ret = set_irq_msi(irq, msidesc);
+			if (ret < 0)
+				goto error_while;
+			printk(KERN_DEBUG "xen: msi already setup: msi --> irq=%d"
+					" pirq=%d\n", irq, pirq);
+			return 0;
+		}
 		xen_allocate_pirq_msi((type == PCI_CAP_ID_MSIX) ?
-				"msi-x" : "msi", &irq, &pirq);
+				"msi-x" : "msi", &irq, &pirq, (XEN_ALLOC_IRQ | XEN_ALLOC_PIRQ));
 		if (irq < 0 || pirq < 0)
 			goto error;
 		printk(KERN_DEBUG "xen: msi --> irq=%d, pirq=%d\n", irq, pirq);