From 1bab1c02aff73eb5c3001e97f48e64ab6a80988a Mon Sep 17 00:00:00 2001 From: Claudio Imbrenda Date: Mon, 29 Aug 2016 15:56:55 +0200 Subject: [PATCH] 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 Reviewed-by: Christian Borntraeger Acked-by: Cornelia Huck Signed-off-by: Christian Borntraeger --- 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 ca21b28a7b17..22b0f49e87c1 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 e65b7637cc45..84c069afc02f 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 8a1dac793d6b..91dc4a87ad61 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 8d018c76ee85..459716de5318 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;