Re: [PATCH v9 04/22] s390/zcrypt: Integrate ap_asm.h into include/asm/ap.h.

[Tony Krowiak]

On 08/14/2018 04:43 AM, Cornelia Huck wrote:
> On Mon, 13 Aug 2018 17:48:01 -0400
> Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote:
>
> > From: Harald Freudenberger <freude@xxxxxxxxxx>
> >
> > Move all the inline functions from the ap bus header
> > file ap_asm.h into the in-kernel api header file
> > arch/s390/include/asm/ap.h so that KVM can make use
> > of all the low level AP functions.
> >
> > Signed-off-by: Harald Freudenberger <freude@xxxxxxxxxx>
> > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
> > ---
> >   arch/s390/include/asm/ap.h     |  284 ++++++++++++++++++++++++++++++++++++----
> >   drivers/s390/crypto/ap_bus.c   |   23 +---
> >   drivers/s390/crypto/ap_bus.h   |    1 +
> >   drivers/s390/crypto/ap_card.c  |    1 -
> >   drivers/s390/crypto/ap_queue.c |    1 -
> >   5 files changed, 260 insertions(+), 50 deletions(-)
> >
> > diff --git a/arch/s390/include/asm/ap.h b/arch/s390/include/asm/ap.h
> > index c1bedb4..887494a 100644
> > --- a/arch/s390/include/asm/ap.h
> > +++ b/arch/s390/include/asm/ap.h
> > @@ -47,6 +47,50 @@ struct ap_queue_status {
> >   };
> >   
> >   /**
> > + * ap_intructions_available() - Test if AP instructions are available.
> > + *
> > + * Returns 1 if the AP instructions are installed, otherwise 0.
> > + */
> > +static inline int ap_instructions_available(void)
> > +{
> > +	register unsigned long reg0 asm ("0") = AP_MKQID(0, 0);
> > +	register unsigned long reg1 asm ("1") = 0;
> > +	register unsigned long reg2 asm ("2") = 0;
> > +
> > +	asm volatile(
> > +		"   .long 0xb2af0000\n"		/* PQAP(TAPQ) */
> > +		"0: la    %0,1\n"
> > +		"1:\n"
> > +		EX_TABLE(0b, 1b)
> > +		: "+d" (reg1), "+d" (reg2)
> > +		: "d" (reg0)
> > +		: "cc");
> > +	return reg1;
> > +}
> I think upstream this change (have this function return !0 when the
> instructions are installed) will be an addon patch to the one which has
> already made its way into master. Not really relevant for the remainder
> of this patch series, though.

I noticed that Harald's patches showed up in our master branch yesterday
without this change.

>