iommu: Remove iommu_[un]register_device_fault_handler()

The individual iommu driver reports the iommu page faults by calling
iommu_report_device_fault(), where a pre-registered device fault handler
is called to route the fault to another fault handler installed on the
corresponding iommu domain.

The pre-registered device fault handler is static and won't be dynamic
as the fault handler is eventually per iommu domain. Replace calling
device fault handler with iommu_queue_iopf().

After this replacement, the registering and unregistering fault handler
interfaces are not needed anywhere. Remove the interfaces and the related
data structures to avoid dead code.

Convert cookie parameter of iommu_queue_iopf() into a device pointer that
is really passed.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Longfang Liu <liulongfang@huawei.com>
Link: https://lore.kernel.org/r/20240212012227.119381-7-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 7 insertions, 17 deletions

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 6fb5f6fceea1..df6ceefc09ee 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4427,23 +4427,15 @@ static int intel_iommu_enable_iopf(struct device *dev)
 	if (ret)
 		return ret;
 
-	ret = iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev);
-	if (ret)
-		goto iopf_remove_device;
-
 	ret = pci_enable_pri(pdev, PRQ_DEPTH);
-	if (ret)
-		goto iopf_unregister_handler;
+	if (ret) {
+		iopf_queue_remove_device(iommu->iopf_queue, dev);
+		return ret;
+	}
+
 	info->pri_enabled = 1;
 
 	return 0;
-
-iopf_unregister_handler:
-	iommu_unregister_device_fault_handler(dev);
-iopf_remove_device:
-	iopf_queue_remove_device(iommu->iopf_queue, dev);
-
-	return ret;
 }
 
 static int intel_iommu_disable_iopf(struct device *dev)
@@ -4466,11 +4458,9 @@ static int intel_iommu_disable_iopf(struct device *dev)
 	info->pri_enabled = 0;
 
 	/*
-	 * With PRI disabled and outstanding PRQs drained, unregistering
-	 * fault handler and removing device from iopf queue should never
-	 * fail.
+	 * With PRI disabled and outstanding PRQs drained, removing device
+	 * from iopf queue should never fail.
 	 */
-	WARN_ON(iommu_unregister_device_fault_handler(dev));
 	WARN_ON(iopf_queue_remove_device(iommu->iopf_queue, dev));
 
 	return 0;