[PATCH v4 3/6] iommu/vt-d: Implement domain ops for attach_dev_pasid

Jacob Pan
2022-05-18T18:18:15Z

On VT-d platforms with scalable mode enabled, devices issue DMA requests
with PASID need to attach PASIDs to given IOMMU domains. The attach
operation involves the following:
- Programming the PASID into the device's PASID table
- Tracking device domain and the PASID relationship
- Managing IOTLB and device TLB invalidations

This patch add attach_dev_pasid functions to the default domain ops which
is used by DMA and identity domain types. It could be extended to support
other domain types whenever necessary.

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 | 72 +++++++++++++++++++++++++++++++++++--
1 file changed, 70 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 1c2c92b657c7..75615c105fdf 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1556,12 +1556,18 @@ static void __iommu_flush_dev_iotlb(struct device_domain_info *info,
u64 addr, unsigned int mask)
{
u16 sid, qdep;
+ ioasid_t pasid;

if (!info || !info->ats_enabled)
return;

sid = info->bus << 8 | info->devfn;
qdep = info->ats_qdep;
+ pasid = iommu_get_pasid_from_domain(info->dev, &info->domain->domain);
+ if (pasid != INVALID_IOASID) {
+ qi_flush_dev_iotlb_pasid(info->iommu, sid, info->pfsid,
+ pasid, qdep, addr, mask);
+ }
qi_flush_dev_iotlb(info->iommu, sid, info->pfsid,
qdep, addr, mask);
}
@@ -1591,6 +1597,7 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
unsigned int mask = ilog2(aligned_pages);
uint64_t addr = (uint64_t)pfn << VTD_PAGE_SHIFT;
u16 did = domain->iommu_did[iommu->seq_id];
+ struct iommu_domain *iommu_domain = &domain->domain;

BUG_ON(pages == 0);

@@ -1599,6 +1606,9 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,

if (domain_use_first_level(domain)) {
qi_flush_piotlb(iommu, did, PASID_RID2PASID, addr, pages, ih);
+ /* flush additional kernel DMA PASIDs attached */
+ if (iommu_domain->dma_pasid)
+ qi_flush_piotlb(iommu, did, iommu_domain->dma_pasid, addr, pages, ih);
} else {
unsigned long bitmask = aligned_pages - 1;

@@ -4255,6 +4265,7 @@ static void __dmar_remove_one_dev_info(struct device_domain_info *info)
struct dmar_domain *domain;
struct intel_iommu *iommu;
unsigned long flags;
+ ioasid_t pasid;

assert_spin_locked(&device_domain_lock);

@@ -4265,10 +4276,15 @@ static void __dmar_remove_one_dev_info(struct device_domain_info *info)
domain = info->domain;

if (info->dev && !dev_is_real_dma_subdevice(info->dev)) {
- if (dev_is_pci(info->dev) && sm_supported(iommu))
+ if (dev_is_pci(info->dev) && sm_supported(iommu)) {
intel_pasid_tear_down_entry(iommu, info->dev,
PASID_RID2PASID, false);
-
+ pasid = iommu_get_pasid_from_domain(info->dev,
+ &info->domain->domain);
+ if (pasid != INVALID_IOASID)
+ intel_pasid_tear_down_entry(iommu, info->dev,
+ pasid, false);
+ }
iommu_disable_dev_iotlb(info);
domain_context_clear(info);
intel_pasid_free_table(info->dev);
@@ -4904,6 +4920,56 @@ static void intel_iommu_iotlb_sync_map(struct iommu_domain *domain,
}
}

+static int intel_iommu_attach_dev_pasid(struct iommu_domain *domain,
+ struct device *dev,
+ ioasid_t pasid)
+{
+ struct device_domain_info *info = dev_iommu_priv_get(dev);
+ struct dmar_domain *dmar_domain = to_dmar_domain(domain);
+ struct intel_iommu *iommu = info->iommu;
+ unsigned long flags;
+ int ret = 0;
+
+ if (!sm_supported(iommu) || !info)
+ return -ENODEV;
+
+ if (WARN_ON(pasid == PASID_RID2PASID))
+ return -EINVAL;
+
+ spin_lock_irqsave(&device_domain_lock, flags);
+ spin_lock(&iommu->lock);
+ if (hw_pass_through && domain_type_is_si(dmar_domain))
+ ret = intel_pasid_setup_pass_through(iommu, dmar_domain,
+ dev, pasid);
+ else if (domain_use_first_level(dmar_domain))
+ ret = domain_setup_first_level(iommu, dmar_domain,
+ dev, pasid);
+ else
+ ret = intel_pasid_setup_second_level(iommu, dmar_domain,
+ dev, pasid);
+
+ spin_unlock(&iommu->lock);
+ spin_unlock_irqrestore(&device_domain_lock, flags);
+
+ return ret;
+}
+
+static void intel_iommu_detach_dev_pasid(struct iommu_domain *domain,
+ struct device *dev,
+ ioasid_t pasid)
+{
+ struct device_domain_info *info = dev_iommu_priv_get(dev);
+ struct intel_iommu *iommu = info->iommu;
+ unsigned long flags;
+
+ if (pasid != iommu_get_pasid_from_domain(info->dev, &info->domain->domain))
+ return;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ intel_pasid_tear_down_entry(iommu, dev, pasid, false);
+ spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
const struct iommu_ops intel_iommu_ops = {
.capable = intel_iommu_capable,
.domain_alloc = intel_iommu_domain_alloc,
@@ -4932,6 +4998,8 @@ const struct iommu_ops intel_iommu_ops = {
.iova_to_phys = intel_iommu_iova_to_phys,
.free = intel_iommu_domain_free,
.enforce_cache_coherency = intel_iommu_enforce_cache_coherency,
+ .attach_dev_pasid = intel_iommu_attach_dev_pasid,
+ .detach_dev_pasid = intel_iommu_detach_dev_pasid,
}
};

--
2.25.1