Messages in this thread | | | Subject | Re: [PATCH v2 08/15] KVM: s390: interface to enable AP execution mode | From | Tony Krowiak <> | Date | Wed, 28 Feb 2018 15:39:55 -0500 |
| |
On 02/28/2018 04:44 AM, David Hildenbrand wrote: > On 27.02.2018 15:28, Tony Krowiak wrote: >> Introduces a new interface to enable AP interpretive >> execution (IE) mode for the KVM guest. When running >> with IE mode enabled, AP instructions executed on the >> KVM guest will be interpreted by the firmware and >> passed directly through to an AP device installed on >> the system. The CPU model feature for AP must >> be enabled for the KVM guest in order to enable >> interpretive execution mode. >> >> This interface will be used in a subsequent patch >> by the VFIO AP device driver. >> >> Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> >> --- >> arch/s390/include/asm/kvm-ap.h | 2 ++ >> arch/s390/include/asm/kvm_host.h | 1 + >> arch/s390/kvm/kvm-ap.c | 27 +++++++++++++++++++++++++++ >> arch/s390/kvm/kvm-s390.h | 1 + >> 4 files changed, 31 insertions(+), 0 deletions(-) >> >> diff --git a/arch/s390/include/asm/kvm-ap.h b/arch/s390/include/asm/kvm-ap.h >> index 46e7c5b..6bd6bfb 100644 >> --- a/arch/s390/include/asm/kvm-ap.h >> +++ b/arch/s390/include/asm/kvm-ap.h >> @@ -51,4 +51,6 @@ struct kvm_ap_matrix { >> >> void kvm_ap_deconfigure_matrix(struct kvm *kvm); >> >> +int kvm_ap_enable_ie_mode(struct kvm *kvm); >> + >> #endif /* _ASM_KVM_AP */ >> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h >> index a4c77d3..1eebdd6 100644 >> --- a/arch/s390/include/asm/kvm_host.h >> +++ b/arch/s390/include/asm/kvm_host.h >> @@ -186,6 +186,7 @@ struct kvm_s390_sie_block { >> #define ECA_AIV 0x00200000 >> #define ECA_VX 0x00020000 >> #define ECA_PROTEXCI 0x00002000 >> +#define ECA_APIE 0x00000008 >> #define ECA_SII 0x00000001 >> __u32 eca; /* 0x004c */ >> #define ICPT_INST 0x04 >> diff --git a/arch/s390/kvm/kvm-ap.c b/arch/s390/kvm/kvm-ap.c >> index bb29045..862e54b 100644 >> --- a/arch/s390/kvm/kvm-ap.c >> +++ b/arch/s390/kvm/kvm-ap.c >> @@ -307,3 +307,30 @@ void kvm_ap_deconfigure_matrix(struct kvm *kvm) >> kvm_ap_clear_crycb_masks(kvm); >> } >> EXPORT_SYMBOL(kvm_ap_deconfigure_matrix); >> + >> +/** >> + * kvm_ap_enable_ie_mode >> + * >> + * Enable interpretrive execution of AP instructions for the guest. When >> + * enabled, AP instructions executed on the guest will be interpreted and >> + * passed through to an AP installed on the host system. >> + * >> + * Returns 0 if interpretrive execution is enabled. Returns -EOPNOTSUPP >> + * if AP facilities are not installed for the guest. >> + * >> + * @kvm: the guest's kvm structure >> + */ >> +int kvm_ap_enable_ie_mode(struct kvm *kvm) >> +{ >> + int i; >> + struct kvm_vcpu *vcpu; >> + >> + if (!test_kvm_cpu_feat(kvm, KVM_S390_VM_CPU_FEAT_AP)) >> + return -EOPNOTSUPP; >> + >> + kvm_for_each_vcpu(i, vcpu, kvm) >> + vcpu->arch.sie_block->eca |= ECA_APIE; >> + >> + return 0; >> +} >> +EXPORT_SYMBOL(kvm_ap_enable_ie_mode); >> diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h >> index 1b5621f..3142541 100644 >> --- a/arch/s390/kvm/kvm-s390.h >> +++ b/arch/s390/kvm/kvm-s390.h >> @@ -18,6 +18,7 @@ >> #include <asm/facility.h> >> #include <asm/processor.h> >> #include <asm/sclp.h> >> +#include <asm/ap.h> >> >> /* Transactional Memory Execution related macros */ >> #define IS_TE_ENABLED(vcpu) ((vcpu->arch.sie_block->ecb & ECB_TE)) >> > And also, what about hot-plugged CPUs? I haven't considered that, do you have any suggestions? >
| |