iommu: Add domain_has_cap iommu_ops
This iommu_op can tell if domain have a specific capability, like snooping
control for Intel IOMMU, which can be used by other components of kernel to
adjust the behaviour.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index be999ff..3778ab1 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -3158,6 +3158,17 @@
return phys;
}
+static int intel_iommu_domain_has_cap(struct iommu_domain *domain,
+ unsigned long cap)
+{
+ struct dmar_domain *dmar_domain = domain->priv;
+
+ if (cap == IOMMU_CAP_CACHE_COHERENCY)
+ return dmar_domain->iommu_snooping;
+
+ return 0;
+}
+
static struct iommu_ops intel_iommu_ops = {
.domain_init = intel_iommu_domain_init,
.domain_destroy = intel_iommu_domain_destroy,
@@ -3166,6 +3177,7 @@
.map = intel_iommu_map_range,
.unmap = intel_iommu_unmap_range,
.iova_to_phys = intel_iommu_iova_to_phys,
+ .domain_has_cap = intel_iommu_domain_has_cap,
};
static void __devinit quirk_iommu_rwbf(struct pci_dev *dev)