On Fri, Aug 30, 2024 at 03:19:16PM +0000, Mostafa Saleh wrote:

quoted

@@ -2263,6 +2266,28 @@ static bool arm_smmu_capable(struct device *dev, enum iommu_cap cap)
 	}
 }
 
+static bool arm_smmu_enforce_cache_coherency(struct iommu_domain *domain)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_master_domain *master_domain;
+	unsigned long flags;
+	bool ret = false;

nit: we can avoid the goto, if we inverse the logic of ret (and set it
to false if device doesn't support CANWBS)

Yeah, that is tidier:

static bool arm_smmu_enforce_cache_coherency(struct iommu_domain *domain)
{
	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
	struct arm_smmu_master_domain *master_domain;
	unsigned long flags;
	bool ret = true;

	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
	list_for_each_entry(master_domain, &smmu_domain->devices,
			    devices_elm) {
		if (!arm_smmu_master_canwbs(master_domain->master)) {
			ret = false;
			break;
		}
	}
	smmu_domain->enforce_cache_coherency = ret;
	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
	return ret;
}

Thanks,
Jason