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

Cornelia Huck
2018-08-17T13:27:03Z

On Fri, 17 Aug 2018 09:18:51 -0400
Tony Krowiak <akrowiak@linux.ibm.com> wrote:

> On 08/14/2018 04:43 AM, Cornelia Huck wrote:
> > On Mon, 13 Aug 2018 17:48:01 -0400
> > Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote:
> >
> >> From: Harald Freudenberger <freude@de.ibm.com>
> >>
> >> 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@de.ibm.com>
> >> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> >> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
> >> ---
> >> 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.

Yep, but the s390/features branch has the patch changing the return
code. Maybe just wait for the next s390 pull request before you
rebase :)