[PATCH v10 20/26] KVM: s390: vsie: allow CRYCB FORMAT-0

Tony Krowiak
2018-09-12T19:43:10Z

From: Pierre Morel <pmorel@linux.ibm.com>

When the host and the guest both use a FORMAT-0 CRYCB,
we copy the guest's FORMAT-0 APCB to a shadow CRYCB
for use by vSIE.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
---
arch/s390/kvm/vsie.c | 20 +++++++++++++++++---
1 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 0a26814..67a5536 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -136,7 +136,15 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
return 0;
}

-/* Copy to APCB FORMAT0 from APCB FORMAT0 */
+/**
+ * setup_apcb00 - Copy to APCB FORMAT0 from APCB FORMAT0
+ * @vcpu: pointer to the virtual CPU
+ * @apcb_s: pointer to start of apcb in the shadow crycb
+ * @apcb_o: pointer to start of original apcb in the guest2
+ * @apcb_h: pointer to start of apcb in the guest1
+ *
+ * Returns 0 and -EFAULT on error reading guest apcb
+ */
static int setup_apcb00(struct kvm_vcpu *vcpu, unsigned long *apcb_s,
unsigned long apcb_o, unsigned long *apcb_h)
{
@@ -209,6 +217,14 @@ static int setup_apcb(struct kvm_vcpu *vcpu, struct kvm_s390_crypto_cb *crycb_s,
return setup_apcb00(vcpu, (unsigned long *) &crycb_s->apcb0,
(unsigned long) &crycb->apcb0,
(unsigned long *) &crycb_h->apcb0);
+ case CRYCB_FORMAT0:
+ if ((crycb_o & PAGE_MASK) != ((crycb_o + 32) & PAGE_MASK))
+ return -EACCES;
+ if (fmt_h != CRYCB_FORMAT0)
+ return -EINVAL;
+ return setup_apcb00(vcpu, (unsigned long *) &crycb_s->apcb0,
+ (unsigned long) &crycb->apcb0,
+ (unsigned long *) &crycb_h->apcb0);
}
return -EINVAL;
}
@@ -248,8 +264,6 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
int ret = 0;

scb_s->crycbd = 0;
- if (!(crycbd_o & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1))
- return 0;

apie_h = vcpu->arch.sie_block->eca & ECA_APIE;
if (!apie_h && !key_msk)
--
1.7.1