On 2/17/2020 6:54 PM, Stefan Metzmacher wrote:
> Am 17.02.20 um 16:40 schrieb Pavel Begunkov:
>> On 2/17/2020 6:18 PM, Stefan Metzmacher wrote:
>>> Hi Pavel,
>>>
>>>> +static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
>>>> +{
>>>> + struct io_splice* sp = &req->splice;
>>>> + unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
>>>> + int ret;
>>>> +
>>>> + if (req->flags & REQ_F_NEED_CLEANUP)
>>>> + return 0;
>>>> +
>>>> + sp->file_in = NULL;
>>>> + sp->off_in = READ_ONCE(sqe->off_in);
>>>> + sp->off_out = READ_ONCE(sqe->off);
>>>> + sp->len = READ_ONCE(sqe->len);
>>>> + sp->flags = READ_ONCE(sqe->splice_flags);
>>>> +
>>>> + if (unlikely(READ_ONCE(sqe->ioprio) || (sp->flags & ~valid_flags)))
>>>> + return -EINVAL;
>>>
>>> Why is ioprio not supported?
>>
>> Because there is no way to set it without changing much of splice code.
>> It may be added later
>>
>> BTW, it seems, only opcodes cares about ioprio are read*/write*.
>> recv*() and send*() don't reject it, but never use.
>
> I guess it's more like a hint, so should we just ignore it until
> it's passed down? Otherwise applications need to do some logic to
> find out if they can pass a value or not.
Then it probably needs to validate the value, but not just ignore it
> I'm not sure what's better, but I think it needs to be discussed...
meh, let's see what Jens think
--
Pavel Begunkov
