On 2/10/23 8:32 AM, Ming Lei wrote: > Hello, > > Add two OPs which buffer is retrieved via kernel splice for supporting > fuse/ublk zero copy. > > The 1st patch enhances direct pipe & splice for moving pages in kernel, > so that the two added OPs won't be misused, and avoid potential security > hole. > > The 2nd patch allows splice_direct_to_actor() caller to ignore signal > if the actor won't block and can be done in bound time. > > The 3rd patch add the two OPs. > > The 4th patch implements ublk's ->splice_read() for supporting > zero copy. > > ublksrv(userspace): > > https://github.com/ming1/ubdsrv/commits/io_uring_splice_buf > > So far, only loop/null target implements zero copy in above branch: > > ublk add -t loop -f $file -z > ublk add -t none -z > > Basic FS/IO function is verified, mount/kernel building & fio > works fine, and big chunk IO(BS: 64k/512k) performance gets improved > obviously. Do you have any performance numbers? Also curious on liburing regression tests, would be nice to see as it helps with review. Caveat - haven't looked into this in detail just yet. -- Jens Axboe
