On Mon, Nov 6, 2023 at 2:51 PM Jens Axboe <axboe@xxxxxxxxx> wrote: > > On 11/6/23 7:32 AM, Jens Axboe wrote: > > On 11/5/23 3:30 PM, Dylan Yudaken wrote: > >> For addr: this field is not used, since buffer select is forced. But by forcing > >> it to be zero it leaves open future uses of the field. > >> > >> len is actually usable, you could imagine that you want to receive > >> multishot up to a certain length. > >> However right now this is not how it is implemented, and it seems > >> safer to force this to be zero. > >> > >> Fixes: fc68fcda0491 ("io_uring/rw: add support for IORING_OP_READ_MULTISHOT") > >> Signed-off-by: Dylan Yudaken <dyudaken@xxxxxxxxx> > >> --- > >> io_uring/rw.c | 7 +++++++ > >> 1 file changed, 7 insertions(+) > >> > >> diff --git a/io_uring/rw.c b/io_uring/rw.c > >> index 1c76de483ef6..ea86498d8769 100644 > >> --- a/io_uring/rw.c > >> +++ b/io_uring/rw.c > >> @@ -111,6 +111,13 @@ int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) > >> rw->len = READ_ONCE(sqe->len); > >> rw->flags = READ_ONCE(sqe->rw_flags); > >> > >> + if (req->opcode == IORING_OP_READ_MULTISHOT) { > >> + if (rw->addr) > >> + return -EINVAL; > >> + if (rw->len) > >> + return -EINVAL; > >> + } > > > > Should we just put these in io_read_mshot_prep() instead? Ala the below. > > In general I think it'd be nice to have a core prep_rw, and then each > > variant will have its own prep. Then we can get away from random opcode > > checking in there. > > > > I do agree with the change in general, just think we can tweak it a bit > > to make it a bit cleaner. > > Sent out two cleanups that take it in this direction in general, fwiw. Yes - I think this approach is better, will rebase on these