From: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxxxxxxx>
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@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Acked-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
---
arch/s390/include/asm/page-states.h | 2 +-
arch/s390/kvm/kvm-s390.c | 8 ++++++--
arch/s390/kvm/priv.c | 6 +++++-
arch/s390/mm/pgtable.c | 6 +++++-
4 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/arch/s390/include/asm/page-states.h b/arch/s390/include/asm/page-states.h
index ca21b28..22b0f49 100644
--- a/arch/s390/include/asm/page-states.h
+++ b/arch/s390/include/asm/page-states.h
@@ -15,6 +15,6 @@
#define ESSA_SET_STABLE_IF_RESIDENT 6
#define ESSA_SET_STABLE_NODAT 7
-#define ESSA_MAX ESSA_SET_STABLE_IF_RESIDENT
+#define ESSA_MAX ESSA_SET_STABLE_NODAT
#endif
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index e65b763..84c069a 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1574,7 +1574,7 @@ static int kvm_s390_get_cmma_bits(struct kvm *kvm,
if (r < 0)
pgstev = 0;
/* save the value */
- res[i++] = (pgstev >> 24) & 0x3;
+ res[i++] = (pgstev >> 24) & 0x43;
/*
* if the next bit is too far away, stop.
* if we reached the previous "next", find the next one
@@ -1652,7 +1652,7 @@ static int kvm_s390_set_cmma_bits(struct kvm *kvm,
pgstev = bits[i];
pgstev = pgstev << 24;
- mask &= _PGSTE_GPS_USAGE_MASK;
+ mask &= _PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT;
set_pgste_bits(kvm->mm, hva, mask, pgstev);
}
srcu_read_unlock(&kvm->srcu, srcu_idx);
@@ -1929,6 +1929,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
set_kvm_facility(kvm->arch.model.fac_mask, 74);
set_kvm_facility(kvm->arch.model.fac_list, 74);
+ if (MACHINE_HAS_TLB_GUEST) {
+ set_kvm_facility(kvm->arch.model.fac_mask, 147);
+ set_kvm_facility(kvm->arch.model.fac_list, 147);
+ }
kvm->arch.model.cpuid = kvm_s390_get_initial_cpuid();
kvm->arch.model.ibc = sclp.ibc & 0x0fff;
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)) {
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 8d018c7..459716d 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -919,7 +919,7 @@ int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
case ESSA_GET_STATE:
break;
case ESSA_SET_STABLE:
- pgstev &= ~_PGSTE_GPS_USAGE_MASK;
+ pgstev &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT);
pgstev |= _PGSTE_GPS_USAGE_STABLE;
break;
case ESSA_SET_UNUSED:
@@ -965,6 +965,10 @@ int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
pgstev |= _PGSTE_GPS_USAGE_STABLE;
}
break;
+ case ESSA_SET_STABLE_NODAT:
+ pgstev &= ~_PGSTE_GPS_USAGE_MASK;
+ pgstev |= _PGSTE_GPS_USAGE_STABLE | _PGSTE_GPS_NODAT;
+ break;
default:
/* we should never get here! */
break;
--
2.7.4
