[PATCH v4 04/10] iommufd: Always pass iommu_attach_handle to iommu core

[Yi Liu <yi.l.liu@xxxxxxxxx>]

The iommu_attach_handle is optional in the RID attach/replace API and the
PASID attach APIs. But it is a mandatory argument for the PASID replace API.
Without it, the PASID replace path cannot get the old domain. Hence, the
PASID path (attach/replace) requires the attach handle. As iommufd is the
major user of the RID attach/replace with iommu_attach_handle, this also
makes the iommufd always pass the attach handle for the RID path as well.
This keeps the RID and PASID path much aligned.

Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
 drivers/iommu/iommufd/fault.c           | 21 +++++++--------------
 drivers/iommu/iommufd/iommufd_private.h | 19 ++++++++++++++++---
 2 files changed, 23 insertions(+), 17 deletions(-)

diff --git a/drivers/iommu/iommufd/fault.c b/drivers/iommu/iommufd/fault.c
index 50ce6c6e61be..9fa56b3c2b7d 100644
--- a/drivers/iommu/iommufd/fault.c
+++ b/drivers/iommu/iommufd/fault.c
@@ -121,7 +121,7 @@ int iommufd_fault_domain_replace_dev(struct iommufd_device *idev,
 {
 	bool iopf_off = !hwpt->fault && old->fault;
 	bool iopf_on = hwpt->fault && !old->fault;
-	struct iommufd_attach_handle *curr = NULL;
+	struct iommufd_attach_handle *curr;
 	int ret;
 
 	if (iopf_on) {
@@ -130,24 +130,17 @@ int iommufd_fault_domain_replace_dev(struct iommufd_device *idev,
 			return ret;
 	}
 
-	if (hwpt->fault) {
-		curr = iommufd_dev_replace_handle(idev, hwpt, old);
-		ret = IS_ERR(curr) ? PTR_ERR(curr) : 0;
-	} else {
-		ret = iommu_replace_group_handle(idev->igroup->group,
-						 hwpt->domain, NULL);
-	}
-
-	if (ret) {
+	curr = iommufd_dev_replace_handle(idev, hwpt, old);
+	if (IS_ERR(curr)) {
 		if (iopf_on)
 			iommufd_fault_iopf_disable(idev);
-		return ret;
+		return PTR_ERR(curr);
 	}
 
-	if (curr) {
+	if (old->fault)
 		iommufd_auto_response_faults(old, curr);
-		kfree(curr);
-	}
+
+	kfree(curr);
 
 	if (iopf_off)
 		iommufd_fault_iopf_disable(idev);
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 7039c86d9981..30696936a926 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -499,6 +499,8 @@ iommufd_dev_replace_handle(struct iommufd_device *idev,
 	int ret;
 
 	curr = iommufd_device_get_attach_handle(idev);
+	if (!curr)
+		return ERR_PTR(-EINVAL);
 
 	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
 	if (!handle)
@@ -541,28 +543,39 @@ static inline int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt,
 	if (hwpt->fault)
 		return iommufd_fault_domain_attach_dev(hwpt, idev);
 
-	return iommu_attach_group(hwpt->domain, idev->igroup->group);
+	return iommufd_dev_attach_handle(hwpt, idev);
 }
 
 static inline void iommufd_hwpt_detach_device(struct iommufd_hw_pagetable *hwpt,
 					      struct iommufd_device *idev)
 {
+	struct iommufd_attach_handle *handle;
+
 	if (hwpt->fault) {
 		iommufd_fault_domain_detach_dev(hwpt, idev);
 		return;
 	}
 
-	iommu_detach_group(hwpt->domain, idev->igroup->group);
+	handle = iommufd_device_get_attach_handle(idev);
+	iommu_detach_group_handle(hwpt->domain, idev->igroup->group);
+	kfree(handle);
 }
 
 static inline int iommufd_hwpt_replace_device(struct iommufd_device *idev,
 					      struct iommufd_hw_pagetable *hwpt,
 					      struct iommufd_hw_pagetable *old)
 {
+	struct iommufd_attach_handle *curr;
+
 	if (old->fault || hwpt->fault)
 		return iommufd_fault_domain_replace_dev(idev, hwpt, old);
 
-	return iommu_group_replace_domain(idev->igroup->group, hwpt->domain);
+	curr = iommufd_dev_replace_handle(idev, hwpt, old);
+	if (IS_ERR(curr))
+		return PTR_ERR(curr);
+
+	kfree(curr);
+	return 0;
 }
 
 #ifdef CONFIG_IOMMUFD_TEST
-- 
2.34.1