[PATCH v5 07/23] iommu/vt-d: fix dev iotlb pfsid use

Jacob Pan
2018-05-11T20:53:59Z

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>
---
drivers/iommu/dmar.c | 6 +++---
drivers/iommu/intel-iommu.c | 16 +++++++++++++++-
include/linux/intel-iommu.h | 5 ++---
3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 460bed4..7852678 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 4623294..732a10f 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -1459,6 +1459,19 @@ 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 if (pdev && pdev->is_virtfn) {
+ if (ecap_dit(info->iommu->ecap))
+ dev_warn(&pdev->dev, "SRIOV VF device IOTLB enabled without flow control\n");
+ info->pfsid = PCI_DEVID(pdev->physfn->bus->number, pdev->physfn->devfn);
+ } else
+ info->pfsid = PCI_DEVID(info->bus, info->devfn);

#ifdef CONFIG_INTEL_IOMMU_SVM
/* The PCIe spec, in its wisdom, declares that the behaviour of
@@ -1524,7 +1537,8 @@ 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);
}
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index dfacd49..678a0f4 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -504,9 +504,8 @@ extern void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid,
u8 fm, u64 type);
extern void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
unsigned int size_order, u64 type);
-extern void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
- u64 addr, unsigned mask);
-
+extern void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid,
+ u16 qdep, u64 addr, unsigned mask);
extern int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu);

extern int dmar_ir_support(void);
--
2.7.4