aio_mlock(2) system call

[Gleb Smirnoff]

On Mon, Jun 03, 2013 at 07:12:55PM +0300, Konstantin Belousov wrote:
K> On Mon, Jun 03, 2013 at 02:06:18PM +0400, Gleb Smirnoff wrote:
K> >   Hello!
K> > 
K> >   This patch brings a new system call - aio_mlock(2). The idea is
K> > quite clear from its name: it performs mlock(2), which can take
K> > a long time if pages aren't resident, under aio(4) control.
K> > 
K> >   The patch is quite simple, and non-desctructive. Here it is
K> > for your review.
K> > 
K> >   If no one objects, I'd like to add it to FreeBSD 10.
K> 
K> I suggest to rename the aio_process() to aio_process_rw().
K> Also, it might make sense to assert aio_lio_opcode value on the entry
K> to aio_process_*() functions.

Will do.

K> > +static void
K> > +aio_process_mlock(struct aiocblist *aiocbe)
K> > +{
K> > +	struct aiocb *cb = &aiocbe->uaiocb;
K> > +	int error;
K> > +
K> > +	error = vm_mlock(aiocbe->userproc, aiocbe->cred,
K> > +	    (void *)(uintptr_t)cb->aio_buf, cb->aio_nbytes);
K> This probably should be spelled __DEVOLATILE().
K> 
K> We traditionally do not reuse the gaps in the syscall table, but add
K> new syscalls at the end.

Hmm. I did that because I wanted to be all aio_* grouped together. Why not?

K> Did you tested the kqueue completion notifications with the aio_mlock() ?

Sure. This is my main use case here.

-- 
Totus tuus, Glebius.