diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 1ccb224f82496..ca66a196f5e97 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -168,6 +168,22 @@ static inline unsigned long virt_to_dma_pfn(void *p)
 	return page_to_dma_pfn(virt_to_page(p));
 }
 
+static inline bool untrusted_dev(struct device *dev)
+{
+	/*
+	 * Treat all external PCI devices as untrusted devices. These are the
+	 * devices behing marked behind external-facing bridges as marked by
+	 * the firmware. The untrusted devices are the ones that can potentially
+	 * execute DMA attacks and similar. They are typically connected through
+	 * external thunderbolt ports. When an IOMMU is enabled they should be
+	 * getting full mappings to ensure they cannot access arbitrary memory.
+	 */
+	if (dev_is_pci(dev) && dev_is_external(dev))
+		return true;
+
+	return false;
+}
+
 /* global iommu list, set NULL for ignored DMAR units */
 static struct intel_iommu **g_iommus;
 
@@ -383,8 +399,7 @@ struct device_domain_info *get_domain_info(struct device *dev)
 DEFINE_SPINLOCK(device_domain_lock);
 static LIST_HEAD(device_domain_list);
 
-#define device_needs_bounce(d) (!intel_no_bounce && dev_is_pci(d) &&	\
-				to_pci_dev(d)->untrusted)
+#define device_needs_bounce(d) (!intel_no_bounce && untrusted_dev(d))
 
 /*
  * Iterate over elements in device_domain_list and call the specified
@@ -2830,7 +2845,7 @@ static int device_def_domain_type(struct device *dev)
 		 * Prevent any device marked as untrusted from getting
 		 * placed into the statically identity mapping domain.
 		 */
-		if (pdev->untrusted)
+		if (untrusted_dev(dev))
 			return IOMMU_DOMAIN_DMA;
 
 		if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
@@ -3464,7 +3479,6 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size)
 	unsigned long iova_pfn;
 	struct intel_iommu *iommu;
 	struct page *freelist;
-	struct pci_dev *pdev = NULL;
 
 	domain = find_domain(dev);
 	BUG_ON(!domain);
@@ -3477,11 +3491,8 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size)
 	start_pfn = mm_to_dma_pfn(iova_pfn);
 	last_pfn = start_pfn + nrpages - 1;
 
-	if (dev_is_pci(dev))
-		pdev = to_pci_dev(dev);
-
 	freelist = domain_unmap(domain, start_pfn, last_pfn);
-	if (intel_iommu_strict || (pdev && pdev->untrusted) ||
+	if (intel_iommu_strict || untrusted_dev(dev) ||
 			!has_iova_flush_queue(&domain->iovad)) {
 		iommu_flush_iotlb_psi(iommu, domain, start_pfn,
 				      nrpages, !freelist, 0);
@@ -4743,7 +4754,7 @@ static inline bool has_untrusted_dev(void)
 	struct pci_dev *pdev = NULL;
 
 	for_each_pci_dev(pdev)
-		if (pdev->untrusted || pdev->external_facing)
+		if (pdev->external_facing || untrusted_dev(&pdev->dev))
 			return true;
 
 	return false;
@@ -6036,7 +6047,7 @@ intel_iommu_domain_set_attr(struct iommu_domain *domain,
  */
 static bool risky_device(struct pci_dev *pdev)
 {
-	if (pdev->untrusted) {
+	if (untrusted_dev(&pdev->dev)) {
 		pci_info(pdev,
 			 "Skipping IOMMU quirk for dev [%04X:%04X] on untrusted PCI link\n",
 			 pdev->vendor, pdev->device);
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index b761c1f72f672..ebd370f4d5b06 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -42,7 +42,7 @@ bool pci_ats_supported(struct pci_dev *dev)
 	if (!dev->ats_cap)
 		return false;
 
-	return (dev->untrusted == 0);
+	return (!dev_is_external(&dev->dev));
 }
 EXPORT_SYMBOL_GPL(pci_ats_supported);
 
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index da6510af12214..9608053a8a62c 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -1630,6 +1630,7 @@ struct bus_type pci_bus_type = {
 	.pm		= PCI_PM_OPS_PTR,
 	.num_vf		= pci_bus_num_vf,
 	.dma_configure	= pci_dma_configure,
+	.supports_site	= true,
 };
 EXPORT_SYMBOL(pci_bus_type);
 
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 79853b52658a2..35f25ac39167b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3330,7 +3330,7 @@ static void pci_std_enable_acs(struct pci_dev *dev)
 	/* Upstream Forwarding */
 	ctrl |= (cap & PCI_ACS_UF);
 
-	if (dev->external_facing || dev->untrusted)
+	if (dev->external_facing || dev_is_external(&dev->dev))
 		/* Translation Blocking */
 		ctrl |= (cap & PCI_ACS_TB);
 
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 8c40c00413e74..1609329cc5b4e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1543,17 +1543,23 @@ static void set_pcie_thunderbolt(struct pci_dev *dev)
 	}
 }
 
-static void set_pcie_untrusted(struct pci_dev *dev)
+static void set_pcie_dev_site(struct pci_dev *dev)
 {
 	struct pci_dev *parent;
 
 	/*
-	 * If the upstream bridge is untrusted we treat this device
-	 * untrusted as well.
+	 * All devices are considered internal by default, unless behind an
+	 * external-facing bridge, as marked by the firmware.
+	 */
+	dev_set_site(&dev->dev, SITE_INTERNAL);
+
+	/*
+	 * If the upstream bridge is external or external-facing, this device
+	 * is also external.
 	 */
 	parent = pci_upstream_bridge(dev);
-	if (parent && (parent->untrusted || parent->external_facing))
-		dev->untrusted = true;
+	if (parent && (parent->external_facing || dev_is_external(&parent->dev)))
+		dev_set_site(&dev->dev, SITE_EXTERNAL);
 }
 
 /**
@@ -1814,7 +1820,7 @@ int pci_setup_device(struct pci_dev *dev)
 	/* Need to have dev->cfg_size ready */
 	set_pcie_thunderbolt(dev);
 
-	set_pcie_untrusted(dev);
+	set_pcie_dev_site(dev);
 
 	/* "Unknown power state" */
 	dev->current_state = PCI_UNKNOWN;
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 6294adeac4049..65d0b8745c915 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4980,7 +4980,7 @@ static int pci_quirk_enable_intel_spt_pch_acs(struct pci_dev *dev)
 	ctrl |= (cap & PCI_ACS_CR);
 	ctrl |= (cap & PCI_ACS_UF);
 
-	if (dev->external_facing || dev->untrusted)
+	if (dev->external_facing || dev_is_external(&dev->dev))
 		/* Translation Blocking */
 		ctrl |= (cap & PCI_ACS_TB);
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index fe1bc603fda40..8bb5065e5aed2 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -424,20 +424,12 @@ struct pci_dev {
 	unsigned int	is_hotplug_bridge:1;
 	unsigned int	shpc_managed:1;		/* SHPC owned by shpchp */
 	unsigned int	is_thunderbolt:1;	/* Thunderbolt controller */
-	/*
-	 * Devices marked being untrusted are the ones that can potentially
-	 * execute DMA attacks and similar. They are typically connected
-	 * through external ports such as Thunderbolt but not limited to
-	 * that. When an IOMMU is enabled they should be getting full
-	 * mappings to make sure they cannot access arbitrary memory.
-	 */
-	unsigned int	untrusted:1;
 	/*
 	 * Devices are marked as external-facing using info from platform
 	 * (ACPI / devicetree). An external-facing device is still an internal
 	 * trusted device, but it faces external untrusted devices. Thus any
 	 * devices enumerated downstream an external-facing device is marked
-	 * as untrusted.
+	 * as external device.
 	 */
 	unsigned int	external_facing:1;
 	unsigned int	broken_intx_masking:1;	/* INTx masking can't be used */
