diff -r d5efa03793a2 xen/arch/x86/msi.c
--- a/xen/arch/x86/msi.c	Thu Jul 10 16:15:37 2008 +0100
+++ b/xen/arch/x86/msi.c	Fri Jul 11 11:51:53 2008 +0200
@@ -173,8 +173,8 @@ static int unset_vector_msi(int vector)
 
 static void write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
-    if ( vtd_enabled )
-        msi_msg_write_remap_rte(entry, msg);
+    if ( iommu_enabled )
+        iommu_update_ire_from_msi(entry, msg);
 
     switch ( entry->msi_attrib.type )
     {
diff -r d5efa03793a2 xen/drivers/passthrough/amd/pci_amd_iommu.c
--- a/xen/drivers/passthrough/amd/pci_amd_iommu.c	Thu Jul 10 16:15:37 2008 +0100
+++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c	Fri Jul 11 11:51:53 2008 +0200
@@ -638,4 +638,6 @@ struct iommu_ops amd_iommu_ops = {
     .unmap_page = amd_iommu_unmap_page,
     .reassign_device = amd_iommu_return_device,
     .get_device_group_id = amd_iommu_group_id,
+    .update_ire_from_apic = amd_iommu_ioapic_update_ire,
+    .update_ire_from_msi = amd_iommu_msi_msg_update_ire,
 };
diff -r d5efa03793a2 xen/drivers/passthrough/iommu.c
--- a/xen/drivers/passthrough/iommu.c	Thu Jul 10 16:15:37 2008 +0100
+++ b/xen/drivers/passthrough/iommu.c	Fri Jul 11 11:51:53 2008 +0200
@@ -290,6 +290,43 @@ int iommu_get_device_group(struct domain
 
     return i;
 }
+
+void iommu_update_ire_from_apic(
+    unsigned int apic, unsigned int reg, unsigned int value)
+{
+    struct iommu_ops *ops = NULL;
+
+    switch ( boot_cpu_data.x86_vendor )
+    {
+    case X86_VENDOR_INTEL:
+        ops = &intel_iommu_ops;
+        break;
+    case X86_VENDOR_AMD:
+        ops = &amd_iommu_ops;
+        break;
+    default:
+        BUG();
+    }
+    ops->update_ire_from_apic(apic, reg, value);
+}
+void iommu_update_ire_from_msi(
+    struct msi_desc *msi_desc, struct msi_msg *msg)
+{
+    struct iommu_ops *ops = NULL;
+
+    switch ( boot_cpu_data.x86_vendor )
+    {
+    case X86_VENDOR_INTEL:
+        ops = &intel_iommu_ops;
+        break;
+    case X86_VENDOR_AMD:
+        ops = &amd_iommu_ops;
+        break;
+    default:
+        BUG();
+    }
+    ops->update_ire_from_msi(msi_desc, msg);
+}
 /*
  * Local variables:
  * mode: C
diff -r d5efa03793a2 xen/drivers/passthrough/vtd/iommu.c
--- a/xen/drivers/passthrough/vtd/iommu.c	Thu Jul 10 16:15:37 2008 +0100
+++ b/xen/drivers/passthrough/vtd/iommu.c	Fri Jul 11 11:51:53 2008 +0200
@@ -1866,6 +1866,8 @@ struct iommu_ops intel_iommu_ops = {
     .unmap_page = intel_iommu_unmap_page,
     .reassign_device = reassign_device_ownership,
     .get_device_group_id = intel_iommu_group_id,
+    .update_ire_from_apic = io_apic_write_remap_rte,
+    .update_ire_from_msi = msi_msg_write_remap_rte,
 };
 
 /*
diff -r d5efa03793a2 xen/include/asm-x86/io_apic.h
--- a/xen/include/asm-x86/io_apic.h	Thu Jul 10 16:15:37 2008 +0100
+++ b/xen/include/asm-x86/io_apic.h	Fri Jul 11 11:51:53 2008 +0200
@@ -133,8 +133,8 @@ static inline unsigned int io_apic_read(
 
 static inline void io_apic_write(unsigned int apic, unsigned int reg, unsigned int value)
 {
-	if (vtd_enabled)
-		return io_apic_write_remap_rte(apic, reg, value);
+	if (iommu_enabled)
+		return iommu_update_ire_from_apic(apic, reg, value);
 	*IO_APIC_BASE(apic) = reg;
 	*(IO_APIC_BASE(apic)+4) = value;
 }
diff -r d5efa03793a2 xen/include/xen/iommu.h
--- a/xen/include/xen/iommu.h	Thu Jul 10 16:15:37 2008 +0100
+++ b/xen/include/xen/iommu.h	Fri Jul 11 11:51:53 2008 +0200
@@ -103,6 +103,10 @@ struct iommu_ops {
     int (*reassign_device)(struct domain *s, struct domain *t,
 			   u8 bus, u8 devfn);
     int (*get_device_group_id)(u8 bus, u8 devfn);
+    void (*update_ire_from_apic)(unsigned int apic, unsigned int reg, unsigned int value);
+    void (*update_ire_from_msi)(struct msi_desc *msi_desc, struct msi_msg *msg);
 };
 
+void iommu_update_ire_from_apic(unsigned int apic, unsigned int reg, unsigned int value);
+void iommu_update_ire_from_msi(struct msi_desc *msi_desc, struct msi_msg *msg);
 #endif /* _IOMMU_H_ */