Re: [PATCH v2 0/4] open/accept directly into io_uring fixed file table

From: Stefan Metzmacher
Date: Mon Aug 16 2021 - 11:45:53 EST


Hi Pavel,

> The behaviour is controlled by setting sqe->file_index, where 0 implies
> the old behaviour. If non-zero value is specified, then it will behave
> as described and place the file into a fixed file slot
> sqe->file_index - 1. A file table should be already created, the slot
> should be valid and empty, otherwise the operation will fail.
>
> Note 1: we can't use IOSQE_FIXED_FILE to switch between modes, because
> accept takes a file, and it already uses the flag with a different
> meaning.

Would it be hard to support IOSQE_FIXED_FILE for the dirfd of openat*, renameat, unlinkat, statx?
(And mkdirat, linkat, symlinkat when they arrive)
renameat and linkat might be trickier as they take two dirfds, but it
would make the feature more complete and useful.

metze