diff --git a/Documentation/virtual/kvm/devices/vm.txt b/Documentation/virtual/kvm/devices/vm.txt index 0ed6808b9965..8a458f42ded2 100644 --- a/Documentation/virtual/kvm/devices/vm.txt +++ b/Documentation/virtual/kvm/devices/vm.txt @@ -112,6 +112,63 @@ Returns: -EFAULT if the given address is not accessible from kernel space. -EBUSY if at least one VCPU has already been defined. 0 in case of success. +2.5. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE_SUBFUNC (r/o) + +Allows user space to retrieve available cpu subfunctions without any filtering +done by a set IBC. These subfunctions are indicated to the guest VCPU via +query or "test bit" subfunctions and used e.g. by cpacf functions, plo and ptff. + +A subfunction block is only valid if KVM_S390_VM_CPU_MACHINE contains the +STFL(E) bit introducing the affected instruction. If the affected instruction +indicates subfunctions via a "query subfunction", the response block is +contained in the returned struct. If the affected instruction +indicates subfunctions via a "test bit" mechanism, the subfunction codes are +contained in the returned struct in MSB 0 bit numbering. + +struct kvm_s390_vm_cpu_subfunc { + u8 plo[32]; # always valid (ESA/390 feature) + u8 ptff[16]; # valid with TOD-clock steering + u8 kmac[16]; # valid with Message-Security-Assist + u8 kmc[16]; # valid with Message-Security-Assist + u8 km[16]; # valid with Message-Security-Assist + u8 kimd[16]; # valid with Message-Security-Assist + u8 klmd[16]; # valid with Message-Security-Assist + u8 pckmo[16]; # valid with Message-Security-Assist-Extension 3 + u8 kmctr[16]; # valid with Message-Security-Assist-Extension 4 + u8 kmf[16]; # valid with Message-Security-Assist-Extension 4 + u8 kmo[16]; # valid with Message-Security-Assist-Extension 4 + u8 pcc[16]; # valid with Message-Security-Assist-Extension 4 + u8 ppno[16]; # valid with Message-Security-Assist-Extension 5 + u8 reserved[1824]; # reserved for future instructions +}; + +Parameters: address of a buffer to load the subfunction blocks from. +Returns: -EFAULT if the given address is not accessible from kernel space. + 0 in case of success. + +2.6. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR_SUBFUNC (r/w) + +Allows user space to retrieve or change cpu subfunctions to be indicated for +all VCPUs of a VM. This attribute will only be available if kernel and +hardware support are in place. + +The kernel uses the configured subfunction blocks for indication to +the guest. A subfunction block will only be used if the associated STFL(E) bit +has not been disabled by user space (so the instruction to be queried is +actually available for the guest). + +As long as no data has been written, a read will fail. The IBC will be used +to determine available subfunctions in this case, this will guarantee backward +compatibility. + +See 2.5. for a description of the parameter struct. + +Parameters: address of a buffer to store/load the subfunction blocks from. +Returns: -EFAULT if the given address is not accessible from kernel space. + -EINVAL when reading, if there was no write yet. + -EBUSY if at least one VCPU has already been defined. + 0 in case of success. + 3. GROUP: KVM_S390_VM_TOD Architectures: s390 diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h index 789c4e27e294..f0818d70d73d 100644 --- a/arch/s390/include/uapi/asm/kvm.h +++ b/arch/s390/include/uapi/asm/kvm.h @@ -102,6 +102,26 @@ struct kvm_s390_vm_cpu_feat { __u64 feat[16]; }; +#define KVM_S390_VM_CPU_PROCESSOR_SUBFUNC 4 +#define KVM_S390_VM_CPU_MACHINE_SUBFUNC 5 +/* for "test bit" instructions MSB 0 bit ordering, for "query" raw blocks */ +struct kvm_s390_vm_cpu_subfunc { + __u8 plo[32]; /* always */ + __u8 ptff[16]; /* with TOD-clock steering */ + __u8 kmac[16]; /* with MSA */ + __u8 kmc[16]; /* with MSA */ + __u8 km[16]; /* with MSA */ + __u8 kimd[16]; /* with MSA */ + __u8 klmd[16]; /* with MSA */ + __u8 pckmo[16]; /* with MSA3 */ + __u8 kmctr[16]; /* with MSA4 */ + __u8 kmf[16]; /* with MSA4 */ + __u8 kmo[16]; /* with MSA4 */ + __u8 pcc[16]; /* with MSA4 */ + __u8 ppno[16]; /* with MSA5 */ + __u8 reserved[1824]; +}; + /* kvm attributes for crypto */ #define KVM_S390_VM_CRYPTO_ENABLE_AES_KW 0 #define KVM_S390_VM_CRYPTO_ENABLE_DEA_KW 1 diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 2b5c14da3227..f746a35e3950 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -36,6 +36,8 @@ #include #include #include +#include +#include #include "kvm-s390.h" #include "gaccess.h" @@ -135,6 +137,8 @@ unsigned long kvm_s390_fac_list_mask_size(void) /* available cpu features supported by kvm */ static DECLARE_BITMAP(kvm_s390_available_cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS); +/* available subfunctions indicated via query / "test bit" */ +static struct kvm_s390_vm_cpu_subfunc kvm_s390_available_subfunc; static struct gmap_notifier gmap_notifier; debug_info_t *kvm_s390_dbf; @@ -198,8 +202,52 @@ static void allow_cpu_feat(unsigned long nr) set_bit_inv(nr, kvm_s390_available_cpu_feat); } +static inline int plo_test_bit(unsigned char nr) +{ + register unsigned long r0 asm("0") = (unsigned long) nr | 0x100; + int cc = 3; /* subfunction not available */ + + asm volatile( + /* Parameter registers are ignored for "test bit" */ + " plo 0,0,0,0(0)\n" + " ipm %0\n" + " srl %0,28\n" + : "=d" (cc) + : "d" (r0) + : "cc"); + return cc == 0; +} + static void kvm_s390_cpu_feat_init(void) { + int i; + + for (i = 0; i < 256; ++i) { + if (plo_test_bit(i)) + kvm_s390_available_subfunc.plo[i >> 3] |= 0x80 >> (i & 7); + } + + if (test_facility(28)) /* TOD-clock steering */ + etr_ptff(kvm_s390_available_subfunc.ptff, ETR_PTFF_QAF); + + if (test_facility(17)) { /* MSA */ + __cpacf_query(CPACF_KMAC, kvm_s390_available_subfunc.kmac); + __cpacf_query(CPACF_KMC, kvm_s390_available_subfunc.kmc); + __cpacf_query(CPACF_KM, kvm_s390_available_subfunc.km); + __cpacf_query(CPACF_KIMD, kvm_s390_available_subfunc.kimd); + __cpacf_query(CPACF_KLMD, kvm_s390_available_subfunc.klmd); + } + if (test_facility(76)) /* MSA3 */ + __cpacf_query(CPACF_PCKMO, kvm_s390_available_subfunc.pckmo); + if (test_facility(77)) { /* MSA4 */ + __cpacf_query(CPACF_KMCTR, kvm_s390_available_subfunc.kmctr); + __cpacf_query(CPACF_KMF, kvm_s390_available_subfunc.kmf); + __cpacf_query(CPACF_KMO, kvm_s390_available_subfunc.kmo); + __cpacf_query(CPACF_PCC, kvm_s390_available_subfunc.pcc); + } + if (test_facility(57)) /* MSA5 */ + __cpacf_query(CPACF_PPNO, kvm_s390_available_subfunc.ppno); + if (MACHINE_HAS_ESOP) allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); } @@ -717,6 +765,16 @@ static int kvm_s390_set_processor_feat(struct kvm *kvm, return ret; } +static int kvm_s390_set_processor_subfunc(struct kvm *kvm, + struct kvm_device_attr *attr) +{ + /* + * Once supported by kernel + hw, we have to store the subfunctions + * in kvm->arch and remember that user space configured them. + */ + return -ENXIO; +} + static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) { int ret = -ENXIO; @@ -728,6 +786,9 @@ static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) case KVM_S390_VM_CPU_PROCESSOR_FEAT: ret = kvm_s390_set_processor_feat(kvm, attr); break; + case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC: + ret = kvm_s390_set_processor_subfunc(kvm, attr); + break; } return ret; } @@ -801,6 +862,25 @@ static int kvm_s390_get_machine_feat(struct kvm *kvm, return 0; } +static int kvm_s390_get_processor_subfunc(struct kvm *kvm, + struct kvm_device_attr *attr) +{ + /* + * Once we can actually configure subfunctions (kernel + hw support), + * we have to check if they were already set by user space, if so copy + * them from kvm->arch. + */ + return -ENXIO; +} + +static int kvm_s390_get_machine_subfunc(struct kvm *kvm, + struct kvm_device_attr *attr) +{ + if (copy_to_user((void __user *)attr->addr, &kvm_s390_available_subfunc, + sizeof(struct kvm_s390_vm_cpu_subfunc))) + return -EFAULT; + return 0; +} static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) { int ret = -ENXIO; @@ -818,6 +898,12 @@ static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) case KVM_S390_VM_CPU_MACHINE_FEAT: ret = kvm_s390_get_machine_feat(kvm, attr); break; + case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC: + ret = kvm_s390_get_processor_subfunc(kvm, attr); + break; + case KVM_S390_VM_CPU_MACHINE_SUBFUNC: + ret = kvm_s390_get_machine_subfunc(kvm, attr); + break; } return ret; } @@ -903,8 +989,11 @@ static int kvm_s390_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr) case KVM_S390_VM_CPU_MACHINE: case KVM_S390_VM_CPU_PROCESSOR_FEAT: case KVM_S390_VM_CPU_MACHINE_FEAT: + case KVM_S390_VM_CPU_MACHINE_SUBFUNC: ret = 0; break; + /* configuring subfunctions is not supported yet */ + case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC: default: ret = -ENXIO; break;