[PATCH v11 6/8] iommu/vt-d: Prepare for set_dev_pasid callback

Jacob Pan posted 8 patches 2 years, 1 month ago
There is a newer version of this series
[PATCH v11 6/8] iommu/vt-d: Prepare for set_dev_pasid callback
Posted by Jacob Pan 2 years, 1 month ago
From: Lu Baolu <baolu.lu@linux.intel.com>

The domain_flush_pasid_iotlb() helper function is used to flush the IOTLB
entries for a given PASID. Previously, this function assumed that
RID2PASID was only used for the first-level DMA translation. However, with
the introduction of the set_dev_pasid callback, this assumption is no
longer valid.

Add a check before using the RID2PASID for PASID invalidation. This check
ensures that the domain has been attached to a physical device before
using RID2PASID.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
 drivers/iommu/intel/iommu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index bdde38a5e43a..4a41aca6a2ba 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1475,7 +1475,8 @@ static void domain_flush_pasid_iotlb(struct intel_iommu *iommu,
 	unsigned long flags;
 
 	spin_lock_irqsave(&domain->lock, flags);
-	qi_flush_piotlb(iommu, did, IOMMU_NO_PASID, addr, npages, ih);
+	if (!list_empty(&domain->devices))
+		qi_flush_piotlb(iommu, did, IOMMU_NO_PASID, addr, npages, ih);
 	spin_unlock_irqrestore(&domain->lock, flags);
 }
 
-- 
2.25.1
RE: [PATCH v11 6/8] iommu/vt-d: Prepare for set_dev_pasid callback
Posted by Tian, Kevin 2 years, 1 month ago
> From: Jacob Pan <jacob.jun.pan@linux.intel.com>
> Sent: Tuesday, July 25, 2023 6:26 AM
> 
> From: Lu Baolu <baolu.lu@linux.intel.com>
> 
> The domain_flush_pasid_iotlb() helper function is used to flush the IOTLB
> entries for a given PASID. Previously, this function assumed that
> RID2PASID was only used for the first-level DMA translation. However, with
> the introduction of the set_dev_pasid callback, this assumption is no
> longer valid.
> 
> Add a check before using the RID2PASID for PASID invalidation. This check
> ensures that the domain has been attached to a physical device before
> using RID2PASID.
> 
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>

Reviewed-by: Kevin Tian <kevin.tian@intel.com>