The Intel IOMMU hardwares support blocking DMA transactions by clearing
the translation table entries. This implements a real blocking domain to
avoid using an empty UNMANAGED domain. The detach_dev callback of the
domain ops is not used in any path. Remove it to avoid dead code as well.
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Tested-by: Tony Zhu <tony.zhu@xxxxxxxxx>
---
drivers/iommu/intel/iommu.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 64d30895a4c8..ffd1ff69bf25 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4127,12 +4127,30 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width)
return 0;
}
+/*
+ * Intel IOMMU blocking domain support:
+ */
+static int blocking_domain_attach_dev(struct iommu_domain *domain,
+ struct device *dev)
+{
+ dmar_remove_one_dev_info(dev);
+ return 0;
+}
+
+static struct iommu_domain blocking_domain = {
+ .ops = &(const struct iommu_domain_ops) {
+ .attach_dev = blocking_domain_attach_dev
+ }
+};
+
static struct iommu_domain *intel_iommu_domain_alloc(unsigned type)
{
struct dmar_domain *dmar_domain;
struct iommu_domain *domain;
switch (type) {
+ case IOMMU_DOMAIN_BLOCKED:
+ return &blocking_domain;
case IOMMU_DOMAIN_DMA:
case IOMMU_DOMAIN_DMA_FQ:
case IOMMU_DOMAIN_UNMANAGED:
@@ -4239,12 +4257,6 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
return domain_add_dev_info(to_dmar_domain(domain), dev);
}
-static void intel_iommu_detach_device(struct iommu_domain *domain,
- struct device *dev)
-{
- dmar_remove_one_dev_info(dev);
-}
-
static int intel_iommu_map(struct iommu_domain *domain,
unsigned long iova, phys_addr_t hpa,
size_t size, int iommu_prot, gfp_t gfp)
@@ -4767,7 +4779,6 @@ const struct iommu_ops intel_iommu_ops = {
#endif
.default_domain_ops = &(const struct iommu_domain_ops) {
.attach_dev = intel_iommu_attach_device,
- .detach_dev = intel_iommu_detach_device,
.map_pages = intel_iommu_map_pages,
.unmap_pages = intel_iommu_unmap_pages,
.iotlb_sync_map = intel_iommu_iotlb_sync_map,
--
2.25.1
