iommu/vt-d: Move capability check code to cap_audit files

Move IOMMU capability check and sanity check code to cap_audit files.
Also implement some helper functions for sanity checks.

Signed-off-by: Kyung Min Park <kyung.min.park@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210130184452.31711-1-kyung.min.park@intel.com
Link: https://lore.kernel.org/r/20210204014401.2846425-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel/cap_audit.c

@@ -183,3 +183,23 @@ int intel_cap_audit(enum cap_audit_type type, struct intel_iommu *iommu)
 
 	return -EFAULT;
 }
+
+bool intel_cap_smts_sanity(void)
+{
+	return ecap_smts(intel_iommu_ecap_sanity);
+}
+
+bool intel_cap_pasid_sanity(void)
+{
+	return ecap_pasid(intel_iommu_ecap_sanity);
+}
+
+bool intel_cap_nest_sanity(void)
+{
+	return ecap_nest(intel_iommu_ecap_sanity);
+}
+
+bool intel_cap_flts_sanity(void)
+{
+	return ecap_flts(intel_iommu_ecap_sanity);
+}

drivers/iommu/intel/cap_audit.h

@@ -107,4 +107,24 @@ enum cap_audit_type {
 	CAP_AUDIT_HOTPLUG_IRQR,
 };
 
+bool intel_cap_smts_sanity(void);
+bool intel_cap_pasid_sanity(void);
+bool intel_cap_nest_sanity(void);
+bool intel_cap_flts_sanity(void);
+
+static inline bool scalable_mode_support(void)
+{
+	return (intel_iommu_sm && intel_cap_smts_sanity());
+}
+
+static inline bool pasid_mode_support(void)
+{
+	return scalable_mode_support() && intel_cap_pasid_sanity();
+}
+
+static inline bool nested_mode_support(void)
+{
+	return scalable_mode_support() && intel_cap_nest_sanity();
+}
+
 int intel_cap_audit(enum cap_audit_type type, struct intel_iommu *iommu);

drivers/iommu/intel/iommu.c

@@ -1864,25 +1864,7 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
  */
 static bool first_level_by_default(void)
 {
-	struct dmar_drhd_unit *drhd;
+	return scalable_mode_support() && intel_cap_flts_sanity();
-	struct intel_iommu *iommu;
-	static int first_level_support = -1;
-
-	if (likely(first_level_support != -1))
-		return first_level_support;
-
-	first_level_support = 1;
-
-	rcu_read_lock();
-	for_each_active_iommu(iommu, drhd) {
-		if (!sm_supported(iommu) || !ecap_flts(iommu->ecap)) {
-			first_level_support = 0;
-			break;
-		}
-	}
-	rcu_read_unlock();
-
-	return first_level_support;
 }
 
 static struct dmar_domain *alloc_domain(int flags)
@@ -5058,60 +5040,6 @@ static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
 	return phys;
 }
 
-static inline bool scalable_mode_support(void)
-{
-	struct dmar_drhd_unit *drhd;
-	struct intel_iommu *iommu;
-	bool ret = true;
-
-	rcu_read_lock();
-	for_each_active_iommu(iommu, drhd) {
-		if (!sm_supported(iommu)) {
-			ret = false;
-			break;
-		}
-	}
-	rcu_read_unlock();
-
-	return ret;
-}
-
-static inline bool iommu_pasid_support(void)
-{
-	struct dmar_drhd_unit *drhd;
-	struct intel_iommu *iommu;
-	bool ret = true;
-
-	rcu_read_lock();
-	for_each_active_iommu(iommu, drhd) {
-		if (!pasid_supported(iommu)) {
-			ret = false;
-			break;
-		}
-	}
-	rcu_read_unlock();
-
-	return ret;
-}
-
-static inline bool nested_mode_support(void)
-{
-	struct dmar_drhd_unit *drhd;
-	struct intel_iommu *iommu;
-	bool ret = true;
-
-	rcu_read_lock();
-	for_each_active_iommu(iommu, drhd) {
-		if (!sm_supported(iommu) || !ecap_nest(iommu->ecap)) {
-			ret = false;
-			break;
-		}
-	}
-	rcu_read_unlock();
-
-	return ret;
-}
-
 static bool intel_iommu_capable(enum iommu_cap cap)
 {
 	if (cap == IOMMU_CAP_CACHE_COHERENCY)
@@ -5352,7 +5280,7 @@ intel_iommu_dev_has_feat(struct device *dev, enum iommu_dev_features feat)
 		int ret;
 
 		if (!dev_is_pci(dev) || dmar_disabled ||
-		    !scalable_mode_support() || !iommu_pasid_support())
+		    !scalable_mode_support() || !pasid_mode_support())
 			return false;
 
 		ret = pci_pasid_features(to_pci_dev(dev));