On 6/18/18 10:16 AM, Al Viro wrote: > On Mon, Jun 18, 2018 at 09:37:01AM -0600, Jens Axboe wrote: > >>> The folks responsible are no longer active in kernel development *** >>> but as far as I know the async write(command), read(response) were >>> added to bsg over 10 years ago as proof-of-concept and never properly >>> worked in this async mode. The biggest design problem with it that I'm >> >> It was born with that mode, but I don't think anyone ever really used it. >> So it might feasible to simply yank it. That said, just doing a prune >> mode at ->release() time doesn't seem like such a hard task. > > "prune mode" being...? Basically what Jann posted, not doing any copy-back of data. Need to verify if the bio unmapping is handled correctly, as some of those will also copy when the end_io handling is invoked. -- Jens Axboe
