[PATCH v10 22/26] KVM: s390: vsie: allow guest FORMAT-1 CRYCB on host FORMAT-2

From: Tony Krowiak
Date: Wed Sep 12 2018 - 15:45:06 EST


From: Pierre Morel <pmorel@xxxxxxxxxxxxx>

When the guest schedules a SIE with a CRYCB FORMAT-1 CRYCB,
we are able to schedule it in the host with a FORMAT-2 CRYCB
if the host uses FORMAT-2.

Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
---
arch/s390/kvm/vsie.c | 33 ++++++++++++++++++++++++++++-----
1 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 90ae310..ca64663 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -135,6 +135,22 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
atomic_set(&scb_s->cpuflags, newflags);
return 0;
}
+/* Copy to APCB FORMAT1 from APCB FORMAT0 */
+static int setup_apcb10(struct kvm_vcpu *vcpu, struct kvm_s390_apcb1 *apcb_s,
+ unsigned long apcb_o, struct kvm_s390_apcb1 *apcb_h)
+{
+ struct kvm_s390_apcb0 tmp;
+
+ if (read_guest_real(vcpu, apcb_o, &tmp, sizeof(struct kvm_s390_apcb0)))
+ return -EFAULT;
+
+ apcb_s->apm[0] = apcb_h->apm[0] & tmp.apm[0];
+ apcb_s->aqm[0] = apcb_h->aqm[0] & tmp.aqm[0] & 0xffff000000000000UL;
+ apcb_s->adm[0] = apcb_h->adm[0] & tmp.adm[0] & 0xffff000000000000UL;
+
+ return 0;
+
+}

/**
* setup_apcb00 - Copy to APCB FORMAT0 from APCB FORMAT0
@@ -212,11 +228,18 @@ static int setup_apcb(struct kvm_vcpu *vcpu, struct kvm_s390_crypto_cb *crycb_s,
(unsigned long) &crycb->apcb1,
(unsigned long *)&crycb_h->apcb1);
case CRYCB_FORMAT1:
- if (fmt_h != CRYCB_FORMAT1)
- return -EINVAL;
- return setup_apcb00(vcpu, (unsigned long *) &crycb_s->apcb0,
- (unsigned long) &crycb->apcb0,
- (unsigned long *) &crycb_h->apcb0);
+ switch (fmt_h) {
+ case CRYCB_FORMAT2:
+ return setup_apcb10(vcpu, &crycb_s->apcb1,
+ (unsigned long) &crycb->apcb0,
+ &crycb_h->apcb1);
+ case CRYCB_FORMAT1:
+ return setup_apcb00(vcpu,
+ (unsigned long *) &crycb_s->apcb0,
+ (unsigned long) &crycb->apcb0,
+ (unsigned long *) &crycb_h->apcb0);
+ }
+ break;
case CRYCB_FORMAT0:
if ((crycb_o & PAGE_MASK) != ((crycb_o + 32) & PAGE_MASK))
return -EACCES;
--
1.7.1