[PATCH v3 4/7] iommu/vt-d: Prepare for global static identity domain

[Lu Baolu <baolu.lu@linux.intel.com>]

With the static identity domain in place, the domain field of per-device
iommu driver data can be either a pointer to a DMA translation domain, or
NULL, indicating that the static identity domain is attached. Refactor
the code to prepare for this change.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/iommu/intel/iommu.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index c019fb3b3e78..f37c8c3cba3c 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1270,6 +1270,9 @@ void domain_update_iotlb(struct dmar_domain *domain)
 	bool has_iotlb_device = false;
 	unsigned long flags;
 
+	if (!domain)
+		return;
+
 	spin_lock_irqsave(&domain->lock, flags);
 	list_for_each_entry(info, &domain->devices, link) {
 		if (info->ats_enabled) {
@@ -3706,11 +3709,9 @@ int prepare_domain_attach_device(struct iommu_domain *domain,
 static int intel_iommu_attach_device(struct iommu_domain *domain,
 				     struct device *dev)
 {
-	struct device_domain_info *info = dev_iommu_priv_get(dev);
 	int ret;
 
-	if (info->domain)
-		device_block_translation(dev);
+	device_block_translation(dev);
 
 	ret = prepare_domain_attach_device(domain, dev);
 	if (ret)
@@ -4321,6 +4322,11 @@ static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 	struct intel_iommu *iommu = info->iommu;
 	unsigned long flags;
 
+	if (domain->type == IOMMU_DOMAIN_IDENTITY) {
+		intel_pasid_tear_down_entry(iommu, dev, pasid, false);
+		return;
+	}
+
 	spin_lock_irqsave(&dmar_domain->lock, flags);
 	list_for_each_entry(curr, &dmar_domain->dev_pasids, link_domain) {
 		if (curr->dev == dev && curr->pasid == pasid) {
-- 
2.34.1