iommu/vt-d: Fix dev iotlb pfsid use

PFSID should be used in the invalidation descriptor for flushing
device IOTLBs on SRIOV VFs.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: "Ashok Raj" <ashok.raj@intel.com>
Cc: "Lu Baolu" <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

2 files changed, 19 insertions, 4 deletions

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 75456b5aa825..d9c748b6f9e4 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1339,8 +1339,8 @@ void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
         qi_submit_sync(&desc, iommu);
 }
 
-void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
-                        u64 addr, unsigned mask)
+void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid,
+                        u16 qdep, u64 addr, unsigned mask)
 {
         struct qi_desc desc;
 
@@ -1355,7 +1355,7 @@ void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
                 qdep = 0;
 
         desc.low = QI_DEV_IOTLB_SID(sid) | QI_DEV_IOTLB_QDEP(qdep) |
-                   QI_DIOTLB_TYPE;
+                   QI_DIOTLB_TYPE | QI_DEV_IOTLB_PFSID(pfsid);
 
         qi_submit_sync(&desc, iommu);
 }
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 7f6194ef48f4..497ef94c5a8c 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -1475,6 +1475,20 @@ static void iommu_enable_dev_iotlb(struct device_domain_info *info)
                 return;
 
         pdev = to_pci_dev(info->dev);
+        /* For IOMMU that supports device IOTLB throttling (DIT), we assign
+         * PFSID to the invalidation desc of a VF such that IOMMU HW can gauge
+         * queue depth at PF level. If DIT is not set, PFSID will be treated as
+         * reserved, which should be set to 0.
+         */
+        if (!ecap_dit(info->iommu->ecap))
+                info->pfsid = 0;
+        else {
+                struct pci_dev *pf_pdev;
+
+                /* pdev will be returned if device is not a vf */
+                pf_pdev = pci_physfn(pdev);
+                info->pfsid = PCI_DEVID(pf_pdev->bus->number, pf_pdev->devfn);
+        }
 
 #ifdef CONFIG_INTEL_IOMMU_SVM
         /* The PCIe spec, in its wisdom, declares that the behaviour of
@@ -1540,7 +1554,8 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
 
                 sid = info->bus << 8 | info->devfn;
                 qdep = info->ats_qdep;
-                qi_flush_dev_iotlb(info->iommu, sid, qdep, addr, mask);
+                qi_flush_dev_iotlb(info->iommu, sid, info->pfsid,
+                                qdep, addr, mask);
         }
         spin_unlock_irqrestore(&device_domain_lock, flags);
 }