[PATCH] iommu/vt-d:Add support for probing ACPI device in RMRR

From: FelixCuioc
Date: Mon Aug 17 2020 - 22:46:37 EST


After acpi device in RMRR is detected,it is necessary
to establish a mapping for these devices.
In acpi_device_create_direct_mappings(),create a mapping
for the acpi device in RMRR.
Add a helper to achieve the acpi namespace device can
access the RMRR region.

Signed-off-by: FelixCuioc <FelixCui-oc@xxxxxxxxxxx>
---
drivers/iommu/intel/iommu.c | 27 +++++++++++++++++++++++++++
drivers/iommu/iommu.c | 6 ++++++
include/linux/iommu.h | 3 +++
3 files changed, 36 insertions(+)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index f774ef63d473..b31f02f41c96 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4797,6 +4797,20 @@ static int __init platform_optin_force_iommu(void)

return 1;
}
+static int acpi_device_create_direct_mappings(struct device *pn_dev, struct device *acpi_device)
+{
+ struct iommu_group *group;
+
+ acpi_device->bus->iommu_ops = &intel_iommu_ops;
+ group = iommu_group_get(pn_dev);
+ if (!group) {
+ pr_warn("ACPI name space devices create direct mappings wrong!\n");
+ return -1;
+ }
+ __acpi_device_create_direct_mappings(group, acpi_device);
+
+ return 0;
+}

static int __init probe_acpi_namespace_devices(void)
{
@@ -4812,6 +4826,7 @@ static int __init probe_acpi_namespace_devices(void)
struct acpi_device_physical_node *pn;
struct iommu_group *group;
struct acpi_device *adev;
+ struct device *pn_dev = NULL;

if (dev->bus != &acpi_bus_type)
continue;
@@ -4822,6 +4837,7 @@ static int __init probe_acpi_namespace_devices(void)
&adev->physical_node_list, node) {
group = iommu_group_get(pn->dev);
if (group) {
+ pn_dev = pn->dev;
iommu_group_put(group);
continue;
}
@@ -4830,7 +4846,18 @@ static int __init probe_acpi_namespace_devices(void)
ret = iommu_probe_device(pn->dev);
if (ret)
break;
+ pn_dev = pn->dev;
+ }
+ if (pn_dev == NULL) {
+ dev->bus->iommu_ops = &intel_iommu_ops;
+ ret = iommu_probe_device(dev);
+ if (ret) {
+ pr_err("acpi_device probe fail! ret:%d\n", ret);
+ return ret;
+ }
+ return 0;
}
+ ret = acpi_device_create_direct_mappings(pn_dev, dev);
mutex_unlock(&adev->physical_node_lock);

if (ret)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 609bd25bf154..4f714a2d5ef7 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -779,6 +779,12 @@ static bool iommu_is_attach_deferred(struct iommu_domain *domain,
return false;
}

+void __acpi_device_create_direct_mappings(struct iommu_group *group, struct device *acpi_device)
+{
+ iommu_create_device_direct_mappings(group, acpi_device);
+}
+EXPORT_SYMBOL_GPL(__acpi_device_create_direct_mappings);
+
/**
* iommu_group_add_device - add a device to an iommu group
* @group: the group into which to add the device (reference should be held)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index fee209efb756..9be134775886 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -514,6 +514,9 @@ extern void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr)
extern int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
unsigned long iova, int flags);

+extern void __acpi_device_create_direct_mappings(struct iommu_group *group,
+ struct device *acpi_device);
+
static inline void iommu_flush_tlb_all(struct iommu_domain *domain)
{
if (domain->ops->flush_iotlb_all)
--
2.17.1