[PATCH 03/17] iommu/vt-d: Move iopf code from SVA to IOPF enabling path

Lu Baolu
2023-04-11T06:49:26Z

Generally enabling IOMMU_DEV_FEAT_SVA requires IOMMU_DEV_FEAT_IOPF, but
some devices manage I/O Page Faults themselves instead of relying on the
IOMMU. Move IOPF related code from SVA to IOPF enabling path.

For the device drivers that relies on the IOMMU for IOPF through PCI/PRI,
IOMMU_DEV_FEAT_IOPF must be enabled before and disabled after
IOMMU_DEV_FEAT_SVA.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20230324120234.313643-4-baolu.lu@linux.intel.com
---
drivers/iommu/intel/iommu.c | 32 ++++++++++++++++++--------------
1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index caf664448ee9..a6f07c74da2d 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4638,7 +4638,6 @@ static int intel_iommu_enable_sva(struct device *dev)
{
struct device_domain_info *info = dev_iommu_priv_get(dev);
struct intel_iommu *iommu;
- int ret;

if (!info || dmar_disabled)
return -EINVAL;
@@ -4667,6 +4666,21 @@ static int intel_iommu_enable_sva(struct device *dev)
if (!info->pri_enabled)
return -EINVAL;

+ return 0;
+}
+
+static int intel_iommu_enable_iopf(struct device *dev)
+{
+ struct device_domain_info *info = dev_iommu_priv_get(dev);
+ struct intel_iommu *iommu;
+ int ret;
+
+ if (!info || !info->ats_enabled || !info->pri_enabled)
+ return -ENODEV;
+ iommu = info->iommu;
+ if (!iommu)
+ return -EINVAL;
+
ret = iopf_queue_add_device(iommu->iopf_queue, dev);
if (ret)
return ret;
@@ -4678,7 +4692,7 @@ static int intel_iommu_enable_sva(struct device *dev)
return ret;
}

-static int intel_iommu_disable_sva(struct device *dev)
+static int intel_iommu_disable_iopf(struct device *dev)
{
struct device_domain_info *info = dev_iommu_priv_get(dev);
struct intel_iommu *iommu = info->iommu;
@@ -4695,16 +4709,6 @@ static int intel_iommu_disable_sva(struct device *dev)
return ret;
}

-static int intel_iommu_enable_iopf(struct device *dev)
-{
- struct device_domain_info *info = dev_iommu_priv_get(dev);
-
- if (info && info->pri_supported)
- return 0;
-
- return -ENODEV;
-}
-
static int
intel_iommu_dev_enable_feat(struct device *dev, enum iommu_dev_features feat)
{
@@ -4725,10 +4729,10 @@ intel_iommu_dev_disable_feat(struct device *dev, enum iommu_dev_features feat)
{
switch (feat) {
case IOMMU_DEV_FEAT_IOPF:
- return 0;
+ return intel_iommu_disable_iopf(dev);

case IOMMU_DEV_FEAT_SVA:
- return intel_iommu_disable_sva(dev);
+ return 0;

default:
return -ENODEV;
--
2.34.1