Merge tag 'thunderbolt-for-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into char-misc-next

Mika writes:

thunderbolt: Changes for v4.21 merge window

* tag 'thunderbolt-for-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt:
  thunderbolt: Export IOMMU based DMA protection support to userspace
  iommu/vt-d: Do not enable ATS for untrusted devices
  iommu/vt-d: Force IOMMU on for platform opt in hint
  PCI / ACPI: Identify untrusted PCI devices

2 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index 843a41ba7e28..f8af1d770520 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -39,6 +39,7 @@ struct acpi_dmar_header;
 /* DMAR Flags */
 #define DMAR_INTR_REMAP         0x1
 #define DMAR_X2APIC_OPT_OUT     0x2
+#define DMAR_PLATFORM_OPT_IN    0x4
 
 struct intel_iommu;
 
@@ -170,6 +171,8 @@ static inline int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
 { return 0; }
 #endif /* CONFIG_IRQ_REMAP */
 
+extern bool dmar_platform_optin(void);
+
 #else /* CONFIG_DMAR_TABLE */
 
 static inline int dmar_device_add(void *handle)
@@ -182,6 +185,11 @@ static inline int dmar_device_remove(void *handle)
         return 0;
 }
 
+static inline bool dmar_platform_optin(void)
+{
+        return false;
+}
+
 #endif /* CONFIG_DMAR_TABLE */
 
 struct irte {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 11c71c4ecf75..c786a2f27bee 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -396,6 +396,14 @@ 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;
         unsigned int    __aer_firmware_first_valid:1;
         unsigned int    __aer_firmware_first:1;
         unsigned int    broken_intx_masking:1;  /* INTx masking can't be used */