As domain->force_snooping only impacts the devices attached with the
domain, there's no need to check against all IOMMU units. At the same
time, for a brand new domain (hasn't been attached to any device), the
force_snooping field could be set, but the attach_dev callback will
return failure if it wants to attach to a device which IOMMU has no
snoop control capability.
Signed-off-by: Lu Baolu <baolu...@linux.intel.com>
---
drivers/iommu/intel/pasid.h | 2 ++
drivers/iommu/intel/iommu.c | 50 ++++++++++++++++++++++++++++++++++++-
drivers/iommu/intel/pasid.c | 18 +++++++++++++
3 files changed, 69 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/intel/pasid.h b/drivers/iommu/intel/pasid.h
index ab4408c824a5..583ea67fc783 100644
--- a/drivers/iommu/intel/pasid.h
+++ b/drivers/iommu/intel/pasid.h
@@ -123,4 +123,6 @@ void intel_pasid_tear_down_entry(struct intel_iommu *iommu,
bool fault_ignore);
int vcmd_alloc_pasid(struct intel_iommu *iommu, u32 *pasid);
void vcmd_free_pasid(struct intel_iommu *iommu, u32 pasid);
+void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu,
+ struct device *dev, u32 pasid);
#endif /* __INTEL_PASID_H */
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 98050943d863..3c1c228f9031 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4554,13 +4554,61 @@ static phys_addr_t intel_iommu_iova_to_phys(struct
iommu_domain *domain,
return phys;
}
+static bool domain_support_force_snooping(struct dmar_domain *domain)
+{
+ struct device_domain_info *info;
+ unsigned long flags;
+ bool support = true;
+
+ spin_lock_irqsave(&device_domain_lock, flags);
+ if (list_empty(&domain->devices))
+ goto out;
+
+ list_for_each_entry(info, &domain->devices, link) {
+ if (!ecap_sc_support(info->iommu->ecap)) {
+ support = false;
+ break;
+ }
+ }
+out:
+ spin_unlock_irqrestore(&device_domain_lock, flags);
+ return support;
+}
+
+static void domain_set_force_snooping(struct dmar_domain *domain)
+{
+ struct device_domain_info *info;
+ unsigned long flags;
+
+ /*
+ * Second level page table supports per-PTE snoop control. The
+ * iommu_map() interface will handle this by setting SNP bit.
+ */
+ if (!domain_use_first_level(domain))
+ return;
+
+ spin_lock_irqsave(&device_domain_lock, flags);
+ if (list_empty(&domain->devices))
+ goto out_unlock;
+
+ list_for_each_entry(info, &domain->devices, link)
+ intel_pasid_setup_page_snoop_control(info->iommu, info->dev,
+ PASID_RID2PASID);
+
+out_unlock:
+ spin_unlock_irqrestore(&device_domain_lock, flags);
+}
+
static bool intel_iommu_enforce_cache_coherency(struct iommu_domain *domain)
{
struct dmar_domain *dmar_domain = to_dmar_domain(domain);
- if (!domain_update_iommu_snooping(NULL))
+ if (!domain_support_force_snooping(dmar_domain))
return false;
+
+ domain_set_force_snooping(dmar_domain);
dmar_domain->force_snooping = true;
+
return true;
}
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index f8d215d85695..815c744e6a34 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -762,3 +762,21 @@ int intel_pasid_setup_pass_through(struct intel_iommu
*iommu,
return 0;
}
+
+/*
+ * Set the page snoop control for a pasid entry which has been set up.
+ */
+void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu,
+ struct device *dev, u32 pasid)
+{
+ struct pasid_entry *pte;
+ u16 did;
+
+ pte = intel_pasid_get_entry(dev, pasid);
+ if (WARN_ON(!pte || !pasid_pte_is_present(pte)))
+ return;
+
+ pasid_set_pgsnp(pte);
+ did = pasid_get_domain_id(pte);
+ pasid_flush_caches(iommu, pte, pasid, did);
+}
--
2.25.1
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