On 10/28/21 9:18 AM, Christoph Hellwig wrote: > On Thu, Oct 28, 2021 at 09:13:07AM -0600, Jens Axboe wrote: >> A couple of suggestions on this: >> >> 1) Don't think we need an IOSQE flag, those are mostly reserved for >> modifiers that apply to (mostly) all kinds of requests >> 2) I think this would be cleaner as a separate command, rather than >> need odd adjustments and iov assumptions. That also gets it out >> of the fast path. >> >> I'd add IORING_OP_READV_PI and IORING_OP_WRITEV_PI for this, I think >> you'd end up with a much cleaner implementation that way. > > Agreed. I also wonder if we could do saner paramter passing. > E.g. pass a separate pointer to the PI data if we find space for > that somewhere in the SQE. Yeah, the whole "put PI in the last iovec" makes the code really ugly dealing with it. Would be a lot cleaner to separate the two. IMHO this is largely a work-around that you'd apply to syscall interfaces that only take the iovec, but we don't need to work around it here if we can define a clean command upfront. And if we don't need vectored requests for the data part, then even better. That one might not be feasible, but figured I'd toss it out there. -- Jens Axboe
