> From: Nicolin Chen <nicolinc@xxxxxxxxxx> > Sent: Wednesday, March 8, 2023 10:26 PM > > Support an access->ioas replacement in iommufd_access_set_ioas(), which > sets the access->ioas to NULL provisionally so that any further incoming > iommufd_access_pin_pages() callback can be blocked. > > Then, call access->ops->unmap() to clean up the entire iopt. To allow an > iommufd_access_unpin_pages() callback to happen via this unmap() call, > add an ioas_unpin pointer so the unpin routine won't be affected by the > "access->ioas = NULL" trick above. > > Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx> > Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>