RE: [PATCH v7 10/28] iommufd/access: Bypass access->ops->unmap for internal use

From: Nicolin Chen nicolinc@nvidia.com Sent: Friday, June 27, 2025 3:35 AM

+int iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova,

• 		unsigned long length)
  

{ struct iommufd_ioas *ioas = container_of(iopt, struct iommufd_ioas, iopt); struct iommufd_access *access; unsigned long index;

• int ret = 0;

  xa_lock(&ioas->iopt.access_list);

• /* Bypass any unmap if there is an internal access */

• xa_for_each(&ioas->iopt.access_list, index, access) {

• if (iommufd_access_is_internal(access)) {
  

• 	ret = -EBUSY;
  

• 	goto unlock;
  

• }
  

• }

hmm all those checks are per iopt. Could do one-off check in iopt_unmap_iova_range() and store the result in a local flag.

Then use that flag to decide whether to return -EBUSY if area->num_accesses is true in the loop.

Reviewed-by: Kevin Tian kevin.tian@intel.com