diff options
author | Christian Borntraeger <borntraeger@de.ibm.com> | 2018-02-09 16:26:29 +0000 |
---|---|---|
committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2018-03-09 09:44:17 +0000 |
commit | c3b9e3e1ea1c1d1524b56b6734711db2a6fc2163 (patch) | |
tree | 42cc07d5944c40ba229de7270008ed4483e2cd1d /arch/s390/kvm | |
parent | f07afa0462b76a5b9c4f3a43d5ac24fdb86a90c2 (diff) |
KVM: s390: implement CPU model only facilities
Some facilities should only be provided to the guest, if they are
enabled by a CPU model. This allows us to avoid capabilities and
to simply fall back to the cpumodel for deciding about a facility
without enabling it for older QEMUs or QEMUs without a CPU
model.
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm')
-rw-r--r-- | arch/s390/kvm/kvm-s390.c | 53 | ||||
-rw-r--r-- | arch/s390/kvm/kvm-s390.h | 2 |
2 files changed, 34 insertions, 21 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 339ac0964590..56061cf82f01 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -152,13 +152,33 @@ static int nested; module_param(nested, int, S_IRUGO); MODULE_PARM_DESC(nested, "Nested virtualization support"); -/* upper facilities limit for kvm */ -unsigned long kvm_s390_fac_list_mask[16] = { FACILITIES_KVM }; -unsigned long kvm_s390_fac_list_mask_size(void) +/* + * For now we handle at most 16 double words as this is what the s390 base + * kernel handles and stores in the prefix page. If we ever need to go beyond + * this, this requires changes to code, but the external uapi can stay. + */ +#define SIZE_INTERNAL 16 + +/* + * Base feature mask that defines default mask for facilities. Consists of the + * defines in FACILITIES_KVM and the non-hypervisor managed bits. + */ +static unsigned long kvm_s390_fac_base[SIZE_INTERNAL] = { FACILITIES_KVM }; +/* + * Extended feature mask. Consists of the defines in FACILITIES_KVM_CPUMODEL + * and defines the facilities that can be enabled via a cpu model. + */ +static unsigned long kvm_s390_fac_ext[SIZE_INTERNAL] = { FACILITIES_KVM_CPUMODEL }; + +static unsigned long kvm_s390_fac_size(void) { - BUILD_BUG_ON(ARRAY_SIZE(kvm_s390_fac_list_mask) > S390_ARCH_FAC_MASK_SIZE_U64); - return ARRAY_SIZE(kvm_s390_fac_list_mask); + BUILD_BUG_ON(SIZE_INTERNAL > S390_ARCH_FAC_MASK_SIZE_U64); + BUILD_BUG_ON(SIZE_INTERNAL > S390_ARCH_FAC_LIST_SIZE_U64); + BUILD_BUG_ON(SIZE_INTERNAL * sizeof(unsigned long) > + sizeof(S390_lowcore.stfle_fac_list)); + + return SIZE_INTERNAL; } /* available cpu features supported by kvm */ @@ -1967,20 +1987,15 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) if (!kvm->arch.sie_page2) goto out_err; - /* Populate the facility mask initially. */ - memcpy(kvm->arch.model.fac_mask, S390_lowcore.stfle_fac_list, - sizeof(S390_lowcore.stfle_fac_list)); - for (i = 0; i < S390_ARCH_FAC_LIST_SIZE_U64; i++) { - if (i < kvm_s390_fac_list_mask_size()) - kvm->arch.model.fac_mask[i] &= kvm_s390_fac_list_mask[i]; - else - kvm->arch.model.fac_mask[i] = 0UL; - } - - /* Populate the facility list initially. */ kvm->arch.model.fac_list = kvm->arch.sie_page2->fac_list; - memcpy(kvm->arch.model.fac_list, kvm->arch.model.fac_mask, - S390_ARCH_FAC_LIST_SIZE_BYTE); + + for (i = 0; i < kvm_s390_fac_size(); i++) { + kvm->arch.model.fac_mask[i] = S390_lowcore.stfle_fac_list[i] & + (kvm_s390_fac_base[i] | + kvm_s390_fac_ext[i]); + kvm->arch.model.fac_list[i] = S390_lowcore.stfle_fac_list[i] & + kvm_s390_fac_base[i]; + } /* we are always in czam mode - even on pre z14 machines */ set_kvm_facility(kvm->arch.model.fac_mask, 138); @@ -4044,7 +4059,7 @@ static int __init kvm_s390_init(void) } for (i = 0; i < 16; i++) - kvm_s390_fac_list_mask[i] |= + kvm_s390_fac_base[i] |= S390_lowcore.stfle_fac_list[i] & nonhyp_mask(i); return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index f55ac0ef99ea..1b5621f4fe5b 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -294,8 +294,6 @@ void exit_sie(struct kvm_vcpu *vcpu); void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu); int kvm_s390_vcpu_setup_cmma(struct kvm_vcpu *vcpu); void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu); -unsigned long kvm_s390_fac_list_mask_size(void); -extern unsigned long kvm_s390_fac_list_mask[]; void kvm_s390_set_cpu_timer(struct kvm_vcpu *vcpu, __u64 cputm); __u64 kvm_s390_get_cpu_timer(struct kvm_vcpu *vcpu); |