iommu: Drop iommu_group_replace_domain()

iommufd does not use it now, so drop it.

Link: https://patch.msgid.link/r/20250226011849.5102-3-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Author: yiliu1765

drivers/iommu/iommu-priv.h

@@ -24,9 +24,6 @@ static inline const struct iommu_ops *iommu_fwspec_ops(struct iommu_fwspec *fwsp
 	return iommu_ops_from_fwnode(fwspec ? fwspec->iommu_fwnode : NULL);
 }
 
-int iommu_group_replace_domain(struct iommu_group *group,
-			       struct iommu_domain *new_domain);
-
 int iommu_device_register_bus(struct iommu_device *iommu,
 			      const struct iommu_ops *ops,
 			      const struct bus_type *bus,

drivers/iommu/iommu.c

@@ -2187,32 +2187,6 @@ int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
 }
 EXPORT_SYMBOL_GPL(iommu_attach_group);
 
-/**
- * iommu_group_replace_domain - replace the domain that a group is attached to
- * @group: IOMMU group that will be attached to the new domain
- * @new_domain: new IOMMU domain to replace with
- *
- * This API allows the group to switch domains without being forced to go to
- * the blocking domain in-between.
- *
- * If the currently attached domain is a core domain (e.g. a default_domain),
- * it will act just like the iommu_attach_group().
- */
-int iommu_group_replace_domain(struct iommu_group *group,
-			       struct iommu_domain *new_domain)
-{
-	int ret;
-
-	if (!new_domain)
-		return -EINVAL;
-
-	mutex_lock(&group->mutex);
-	ret = __iommu_group_set_domain(group, new_domain);
-	mutex_unlock(&group->mutex);
-	return ret;
-}
-EXPORT_SYMBOL_NS_GPL(iommu_group_replace_domain, "IOMMUFD_INTERNAL");
-
 static int __iommu_device_set_domain(struct iommu_group *group,
 				     struct device *dev,
 				     struct iommu_domain *new_domain,
@@ -3558,9 +3532,12 @@ EXPORT_SYMBOL_NS_GPL(iommu_detach_group_handle, "IOMMUFD_INTERNAL");
  * @new_domain: new IOMMU domain to replace with
  * @handle: attach handle
  *
- * This is a variant of iommu_group_replace_domain(). It allows the caller to
- * provide an attach handle for the new domain and use it when the domain is
- * attached.
+ * This API allows the group to switch domains without being forced to go to
+ * the blocking domain in-between. It allows the caller to provide an attach
+ * handle for the new domain and use it when the domain is attached.
+ *
+ * If the currently attached domain is a core domain (e.g. a default_domain),
+ * it will act just like the iommu_attach_group_handle().
  */
 int iommu_replace_group_handle(struct iommu_group *group,
 			       struct iommu_domain *new_domain,