Re: linux-aio usable?

Christoph Hellwig
2010-03-09T14:12:49Z

On Tue, Mar 09, 2010 at 12:05:49PM +0200, Avi Kivity wrote:
>> http://thread.gmane.org/gmane.linux.kernel.aio.general/2891
>>
>> It's missing compat_ioctl for some of the aio opcodes, namely
>> it's PREADV and PWRITE - the only ones used by kvm and the only
>> ones missing in kernel.
>>
>> As far as i can see, current code converts the iocb array just
>> fine, but does not touch iovec array used with p{read,write}v.
>>
>
> Yikes, looks pretty bad.

No need for compat_ioctl handlers as there are no ioctls involved
in aio, we just need better compat versions of io_submit, which
by itself is a bit of an ioctl-like multiplexer.

Adding the vector compat might be a bit messy, but shouldn't be
too hard given that we already deal with this for native
(p)readv/(p)writev.