KVM: s390: expose no-DAT to guest and migration support
The STFLE bit 147 indicates whether the ESSA no-DAT operation code is
valid, the bit is not normally provided to the host; the host is
instead provided with an SCLP bit that indicates whether guests can
support the feature.
This patch:
* enables the STFLE bit in the guest if the corresponding SCLP bit is
present in the host.
* adds support for migrating the no-DAT bit in the PGSTEs
* fixes the software interpretation of the ESSA instruction that is
used when migrating, both for the new operation code and for the old
"set stable", as per specifications.
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 8a1dac7..91dc4a8 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -988,6 +988,8 @@ static inline int do_essa(struct kvm_vcpu *vcpu, const int orc)
if (pgstev & _PGSTE_GPS_ZERO)
res |= 1;
}
+ if (pgstev & _PGSTE_GPS_NODAT)
+ res |= 0x20;
vcpu->run->s.regs.gprs[r1] = res;
/*
* It is possible that all the normal 511 slots were full, in which case
@@ -1027,7 +1029,9 @@ static int handle_essa(struct kvm_vcpu *vcpu)
return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
/* Check for invalid operation request code */
orc = (vcpu->arch.sie_block->ipb & 0xf0000000) >> 28;
- if (orc > ESSA_MAX)
+ /* ORCs 0-6 are always valid */
+ if (orc > (test_kvm_facility(vcpu->kvm, 147) ? ESSA_SET_STABLE_NODAT
+ : ESSA_SET_STABLE_IF_RESIDENT))
return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
if (likely(!vcpu->kvm->arch.migration_state)) {