On Wed, Apr 22, 2020 at 8:06 AM Michael Kerrisk (man-pages) <mtk.manpages@xxxxxxxxx> wrote: > > [CC += linux-api] > > On Wed, 22 Apr 2020 at 07:20, Josh Triplett <josh@xxxxxxxxxxxxxxxx> wrote: > > > > Inspired by the X protocol's handling of XIDs, allow userspace to select > > the file descriptor opened by openat2, so that it can use the resulting > > file descriptor in subsequent system calls without waiting for the > > response to openat2. > > > > In io_uring, this allows sequences like openat2/read/close without > > waiting for the openat2 to complete. Multiple such sequences can > > overlap, as long as each uses a distinct file descriptor. If this is primarily an io_uring feature, then why burden the normal openat2 API with this? Add this flag to the io_uring API, by all means. This would also allow Implementing a private fd table for io_uring. I.e. add a flag interpreted by file ops (IORING_PRIVATE_FD), including openat2 and freely use the private fd space without having to worry about interactions with other parts of the system. Thanks, Miklos
