On Fri, Mar 21, 2025 at 05:14:59AM -0600, Jens Axboe wrote: > On 3/20/25 11:56 PM, Christoph Hellwig wrote: > >> I don't know the entire historical context, but I presume sendmsg > >> did that because there was no other mechanism at the time. > > > > At least aio had been around for about 15 years at the point, but > > networking folks tend to be pretty insular and reinvent things. > > Yep... > > >> It seems like Jens suggested that plumbing this through for splice > >> was a possibility, but sounds like you disagree. > > > > Yes, very strongly. > > And that is very much not what I suggested, fwiw. Your earlier message said: If the answer is "because splice", then it would seem saner to plumb up those bits only. Would be much simpler too... wherein I interpreted "plumb those bits" to mean plumbing the error queue notifications on TX completions. My sincere apologies that I misunderstood your prior message and/or misconstrued what you said -- it was not clear to me what you meant. It is clear to me now, though, that adding a flag to splice as previously proposed and extending sendfile based on the SO_ZEROCOPY sock flag being set are both unacceptable solutions. If you happen to have a suggestion of some piece of code that I should read (other than the iouring implementation) to inform how I might build an RFCv2, I would appreciate the pointer. Thanks for your time and energy, Joe
