iommufd/device: Only add reserved_iova in non-pasid path

As the pasid is passed through the attach/replace/detach helpers, it is
necessary to ensure only the non-pasid path adds reserved_iova.

Link: https://patch.msgid.link/r/20250321171940.7213-5-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Author: yiliu1765

drivers/iommu/iommufd/device.c

@@ -483,6 +483,7 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
 				struct iommufd_device *idev, ioasid_t pasid)
 {
 	struct iommufd_hwpt_paging *hwpt_paging = find_hwpt_paging(hwpt);
+	bool attach_resv = hwpt_paging && pasid == IOMMU_NO_PASID;
 	int rc;
 
 	mutex_lock(&idev->igroup->lock);
@@ -492,7 +493,7 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
 		goto err_unlock;
 	}
 
-	if (hwpt_paging) {
+	if (attach_resv) {
 		rc = iommufd_device_attach_reserved_iova(idev, hwpt_paging);
 		if (rc)
 			goto err_unlock;
@@ -516,7 +517,7 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
 	mutex_unlock(&idev->igroup->lock);
 	return 0;
 err_unresv:
-	if (hwpt_paging)
+	if (attach_resv)
 		iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, idev->dev);
 err_unlock:
 	mutex_unlock(&idev->igroup->lock);
@@ -535,7 +536,7 @@ iommufd_hw_pagetable_detach(struct iommufd_device *idev, ioasid_t pasid)
 		iommufd_hwpt_detach_device(hwpt, idev, pasid);
 		idev->igroup->hwpt = NULL;
 	}
-	if (hwpt_paging)
+	if (hwpt_paging && pasid == IOMMU_NO_PASID)
 		iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, idev->dev);
 	mutex_unlock(&idev->igroup->lock);
 
@@ -602,6 +603,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
 			  struct iommufd_hw_pagetable *hwpt)
 {
 	struct iommufd_hwpt_paging *hwpt_paging = find_hwpt_paging(hwpt);
+	bool attach_resv = hwpt_paging && pasid == IOMMU_NO_PASID;
 	struct iommufd_hwpt_paging *old_hwpt_paging;
 	struct iommufd_group *igroup = idev->igroup;
 	struct iommufd_hw_pagetable *old_hwpt;
@@ -626,7 +628,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
 	}
 
 	old_hwpt = igroup->hwpt;
-	if (hwpt_paging) {
+	if (attach_resv) {
 		rc = iommufd_group_do_replace_reserved_iova(igroup, hwpt_paging);
 		if (rc)
 			goto err_unlock;
@@ -637,7 +639,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
 		goto err_unresv;
 
 	old_hwpt_paging = find_hwpt_paging(old_hwpt);
-	if (old_hwpt_paging &&
+	if (old_hwpt_paging && pasid == IOMMU_NO_PASID &&
 	    (!hwpt_paging || hwpt_paging->ioas != old_hwpt_paging->ioas))
 		iommufd_group_remove_reserved_iova(igroup, old_hwpt_paging);
 
@@ -657,7 +659,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
 	/* Caller must destroy old_hwpt */
 	return old_hwpt;
 err_unresv:
-	if (hwpt_paging)
+	if (attach_resv)
 		iommufd_group_remove_reserved_iova(igroup, hwpt_paging);
 err_unlock:
 	mutex_unlock(&idev->igroup->lock);