[PATCH v3 1/2] iommu/vt-d:Add support for detecting ACPI device in RMRR

[FelixCuioc]

Some ACPI devices need to issue dma requests to access
the reserved memory area.BIOS uses the device scope type
ACPI_NAMESPACE_DEVICE in RMRR to report these ACPI devices.
This patch add support for detecting ACPI devices in RMRR.

Signed-off-by: FelixCuioc <FelixCui-oc@xxxxxxxxxxx>
---
 drivers/iommu/intel/dmar.c  | 76 +++++++++++++++++++++----------------
 drivers/iommu/intel/iommu.c | 23 ++++++++++-
 include/linux/dmar.h        | 12 +++++-
 3 files changed, 76 insertions(+), 35 deletions(-)

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 54d790f75824..5ebe317280a6 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -215,7 +215,7 @@ static bool dmar_match_pci_path(struct dmar_pci_notify_info *info, int bus,
 }
 
 /* Return: > 0 if match found, 0 if no match found, < 0 if error happens */
-int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
+int dmar_pci_insert_dev_scope(struct dmar_pci_notify_info *info,
 			  void *start, void*end, u16 segment,
 			  struct dmar_dev_scope *devices,
 			  int devices_cnt)
@@ -304,7 +304,7 @@ static int dmar_pci_bus_add_dev(struct dmar_pci_notify_info *info)
 
 		drhd = container_of(dmaru->hdr,
 				    struct acpi_dmar_hardware_unit, header);
-		ret = dmar_insert_dev_scope(info, (void *)(drhd + 1),
+		ret = dmar_pci_insert_dev_scope(info, (void *)(drhd + 1),
 				((void *)drhd) + drhd->header.length,
 				dmaru->segment,
 				dmaru->devices, dmaru->devices_cnt);
@@ -697,47 +697,59 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev)
 	return dmaru;
 }
 
-static void __init dmar_acpi_insert_dev_scope(u8 device_number,
-					      struct acpi_device *adev)
+/* Return: > 0 if match found, 0 if no match found */
+bool dmar_acpi_insert_dev_scope(u8 device_number,
+				struct acpi_device *adev,
+				void *start, void *end,
+				struct dmar_dev_scope *devices,
+				int devices_cnt)
 {
-	struct dmar_drhd_unit *dmaru;
-	struct acpi_dmar_hardware_unit *drhd;
 	struct acpi_dmar_device_scope *scope;
 	struct device *tmp;
 	int i;
 	struct acpi_dmar_pci_path *path;
 
+	for (; start < end; start += scope->length) {
+		scope = start;
+		if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
+			continue;
+		if (scope->enumeration_id != device_number)
+			continue;
+		path = (void *)(scope + 1);
+		for_each_dev_scope(devices, devices_cnt, i, tmp)
+			if (tmp == NULL) {
+				devices[i].bus = scope->bus;
+				devices[i].devfn = PCI_DEVFN(path->device, path->function);
+				rcu_assign_pointer(devices[i].dev,
+						   get_device(&adev->dev));
+				return true;
+			}
+		WARN_ON(i >= devices_cnt);
+	}
+	return false;
+}
+
+static int dmar_acpi_bus_add_dev(u8 device_number, struct acpi_device *adev)
+{
+	struct dmar_drhd_unit *dmaru;
+	struct acpi_dmar_hardware_unit *drhd;
+	int ret;
+
 	for_each_drhd_unit(dmaru) {
 		drhd = container_of(dmaru->hdr,
 				    struct acpi_dmar_hardware_unit,
 				    header);
+		ret = dmar_acpi_insert_dev_scope(device_number, adev, (void *)(drhd+1),
+						((void *)drhd)+drhd->header.length,
+						dmaru->devices, dmaru->devices_cnt);
+		if (ret)
+			break;
+	}
+	if (ret > 0)
+		ret = dmar_rmrr_add_acpi_dev(device_number, adev);
 
-		for (scope = (void *)(drhd + 1);
-		     (unsigned long)scope < ((unsigned long)drhd) + drhd->header.length;
-		     scope = ((void *)scope) + scope->length) {
-			if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
-				continue;
-			if (scope->enumeration_id != device_number)
-				continue;
+	return ret;
 
-			path = (void *)(scope + 1);
-			pr_info("ACPI device \"%s\" under DMAR at %llx as %02x:%02x.%d\n",
-				dev_name(&adev->dev), dmaru->reg_base_addr,
-				scope->bus, path->device, path->function);
-			for_each_dev_scope(dmaru->devices, dmaru->devices_cnt, i, tmp)
-				if (tmp == NULL) {
-					dmaru->devices[i].bus = scope->bus;
-					dmaru->devices[i].devfn = PCI_DEVFN(path->device,
-									    path->function);
-					rcu_assign_pointer(dmaru->devices[i].dev,
-							   get_device(&adev->dev));
-					return;
-				}
-			BUG_ON(i >= dmaru->devices_cnt);
-		}
-	}
-	pr_warn("No IOMMU scope found for ANDD enumeration ID %d (%s)\n",
-		device_number, dev_name(&adev->dev));
 }
 
 static int __init dmar_acpi_dev_scope_init(void)
@@ -766,7 +778,7 @@ static int __init dmar_acpi_dev_scope_init(void)
 				       andd->device_name);
 				continue;
 			}
-			dmar_acpi_insert_dev_scope(andd->device_number, adev);
+			dmar_acpi_bus_add_dev(andd->device_number, adev);
 		}
 	}
 	return 0;
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 2485441445cf..594b2f29c043 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4553,6 +4553,25 @@ int dmar_find_matched_atsr_unit(struct pci_dev *dev)
 	return ret;
 }
 
+int dmar_rmrr_add_acpi_dev(u8 device_number, struct acpi_device *adev)
+{
+	int ret;
+	struct dmar_rmrr_unit *rmrru;
+	struct acpi_dmar_reserved_memory *rmrr;
+
+	list_for_each_entry(rmrru, &dmar_rmrr_units, list) {
+		rmrr = container_of(rmrru->hdr,
+				struct acpi_dmar_reserved_memory,
+				header);
+		ret = dmar_acpi_insert_dev_scope(device_number, adev, (void *)(rmrr + 1),
+						((void *)rmrr) + rmrr->header.length,
+						rmrru->devices, rmrru->devices_cnt);
+		if (ret)
+			break;
+	}
+	return 0;
+}
+
 int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 {
 	int ret;
@@ -4568,7 +4587,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 		rmrr = container_of(rmrru->hdr,
 				    struct acpi_dmar_reserved_memory, header);
 		if (info->event == BUS_NOTIFY_ADD_DEVICE) {
-			ret = dmar_insert_dev_scope(info, (void *)(rmrr + 1),
+			ret = dmar_pci_insert_dev_scope(info, (void *)(rmrr + 1),
 				((void *)rmrr) + rmrr->header.length,
 				rmrr->segment, rmrru->devices,
 				rmrru->devices_cnt);
@@ -4586,7 +4605,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 
 		atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
 		if (info->event == BUS_NOTIFY_ADD_DEVICE) {
-			ret = dmar_insert_dev_scope(info, (void *)(atsr + 1),
+			ret = dmar_pci_insert_dev_scope(info, (void *)(atsr + 1),
 					(void *)atsr + atsr->header.length,
 					atsr->segment, atsru->devices,
 					atsru->devices_cnt);
diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index 65565820328a..d0981d35d3c9 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -113,10 +113,14 @@ extern int dmar_parse_dev_scope(void *start, void *end, int *cnt,
 				struct dmar_dev_scope **devices, u16 segment);
 extern void *dmar_alloc_dev_scope(void *start, void *end, int *cnt);
 extern void dmar_free_dev_scope(struct dmar_dev_scope **devices, int *cnt);
-extern int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
+extern int dmar_pci_insert_dev_scope(struct dmar_pci_notify_info *info,
 				 void *start, void*end, u16 segment,
 				 struct dmar_dev_scope *devices,
 				 int devices_cnt);
+extern bool dmar_acpi_insert_dev_scope(u8 device_number,
+				struct acpi_device *adev, void *start, void *end,
+				struct dmar_dev_scope *devices, int devices_cnt);
+
 extern int dmar_remove_dev_scope(struct dmar_pci_notify_info *info,
 				 u16 segment, struct dmar_dev_scope *devices,
 				 int count);
@@ -140,6 +144,7 @@ extern int dmar_parse_one_atsr(struct acpi_dmar_header *header, void *arg);
 extern int dmar_check_one_atsr(struct acpi_dmar_header *hdr, void *arg);
 extern int dmar_release_one_atsr(struct acpi_dmar_header *hdr, void *arg);
 extern int dmar_iommu_hotplug(struct dmar_drhd_unit *dmaru, bool insert);
+extern int dmar_rmrr_add_acpi_dev(u8 device_number, struct acpi_device *adev);
 extern int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info);
 #else /* !CONFIG_INTEL_IOMMU: */
 static inline int intel_iommu_init(void) { return -ENODEV; }
@@ -150,6 +155,11 @@ static inline void intel_iommu_shutdown(void) { }
 #define	dmar_check_one_atsr		dmar_res_noop
 #define	dmar_release_one_atsr		dmar_res_noop
 
+static inline int dmar_rmrr_add_acpi_dev(u8 device_number, struct acpi_device *adev)
+{
+	return 0;
+}
+
 static inline int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 {
 	return 0;
-- 
2.17.1