On 8/27/22 15:46, Al Viro wrote: > On Sat, Aug 27, 2022 at 01:36:04AM -0700, John Hubbard wrote: >> Provide two new wrapper routines that are intended for user space pages >> only: >> >> iov_iter_pin_pages() >> iov_iter_pin_pages_alloc() >> >> Internally, these routines call pin_user_pages_fast(), instead of >> get_user_pages_fast(). >> >> As always, callers must use unpin_user_pages() or a suitable FOLL_PIN >> variant, to release the pages, if they actually were acquired via >> pin_user_pages_fast(). >> >> This is a prerequisite to converting bio/block layers over to use >> pin_user_pages_fast(). > > You do realize that O_DIRECT on ITER_BVEC is possible, right? I do now. But I didn't until you wrote this! Any advice or ideas would be welcome here. thanks, -- John Hubbard NVIDIA