intel-iommu: use physfn to search drhd for VF

When virtfn is used, we should use physfn to find correct drhd

-v2: add pci_physfn() Suggested by Roland Dreier <rdreier@cisco.com>
     do can remove ifdef in dmar.c
-v3: Chris pointed out we need that for dma_find_matched_atsr_unit too
     also change dmar_pci_device_match() static

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Roland Dreier <rdreier@cisco.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index d439917..edc5f00 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -309,6 +309,8 @@
 	struct acpi_dmar_atsr *atsr;
 	struct dmar_atsr_unit *atsru;
 
+	dev = pci_physfn(dev);
+
 	list_for_each_entry(atsru, &dmar_atsr_units, list) {
 		atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
 		if (atsr->segment == pci_domain_nr(dev->bus))
@@ -507,7 +509,7 @@
 	return ret;
 }
 
-int dmar_pci_device_match(struct pci_dev *devices[], int cnt,
+static int dmar_pci_device_match(struct pci_dev *devices[], int cnt,
 			  struct pci_dev *dev)
 {
 	int index;
@@ -530,6 +532,8 @@
 	struct dmar_drhd_unit *dmaru = NULL;
 	struct acpi_dmar_hardware_unit *drhd;
 
+	dev = pci_physfn(dev);
+
 	list_for_each_entry(dmaru, &dmar_drhd_units, list) {
 		drhd = container_of(dmaru->hdr,
 				    struct acpi_dmar_hardware_unit,