diff options
| -rw-r--r-- | Documentation/virtual/kvm/devices/vm.txt | 27 | ||||
| -rw-r--r-- | arch/s390/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/s390/include/uapi/asm/kvm.h | 8 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 63 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.h | 6 |
5 files changed, 106 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/vm.txt b/Documentation/virtual/kvm/devices/vm.txt index a9ea8774a45f..0ed6808b9965 100644 --- a/Documentation/virtual/kvm/devices/vm.txt +++ b/Documentation/virtual/kvm/devices/vm.txt @@ -85,6 +85,33 @@ Returns: -EBUSY in case 1 or more vcpus are already activated (only in write -ENOMEM if not enough memory is available to process the ioctl 0 in case of success +2.3. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE_FEAT (r/o) + +Allows user space to retrieve available cpu features. A feature is available if +provided by the hardware and supported by kvm. In theory, cpu features could +even be completely emulated by kvm. + +struct kvm_s390_vm_cpu_feat { + __u64 feat[16]; # Bitmap (1 = feature available), MSB 0 bit numbering +}; + +Parameters: address of a buffer to load the feature list from. +Returns: -EFAULT if the given address is not accessible from kernel space. + 0 in case of success. + +2.4. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR_FEAT (r/w) + +Allows user space to retrieve or change enabled cpu features for all VCPUs of a +VM. Features that are not available cannot be enabled. + +See 2.3. for a description of the parameter struct. + +Parameters: address of a buffer to store/load the feature list from. +Returns: -EFAULT if the given address is not accessible from kernel space. + -EINVAL if a cpu feature that is not available is to be enabled. + -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/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index bcc20dc91ea8..b2a83a0ce42c 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -658,6 +658,8 @@ struct kvm_arch{ struct kvm_s390_cpu_model model; struct kvm_s390_crypto crypto; u64 epoch; + /* subset of available cpu features enabled by user space */ + DECLARE_BITMAP(cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS); }; #define KVM_HVA_ERR_BAD (-1UL) diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h index 3b8e99ef9d58..a8559f265e26 100644 --- a/arch/s390/include/uapi/asm/kvm.h +++ b/arch/s390/include/uapi/asm/kvm.h @@ -93,6 +93,14 @@ struct kvm_s390_vm_cpu_machine { __u64 fac_list[256]; }; +#define KVM_S390_VM_CPU_PROCESSOR_FEAT 2 +#define KVM_S390_VM_CPU_MACHINE_FEAT 3 + +#define KVM_S390_VM_CPU_FEAT_NR_BITS 1024 +struct kvm_s390_vm_cpu_feat { + __u64 feat[16]; +}; + /* 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 44297ff53b44..6960468f28ad 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -26,6 +26,7 @@ #include <linux/slab.h> #include <linux/timer.h> #include <linux/vmalloc.h> +#include <linux/bitmap.h> #include <asm/asm-offsets.h> #include <asm/lowcore.h> #include <asm/etr.h> @@ -132,6 +133,9 @@ unsigned long kvm_s390_fac_list_mask_size(void) return ARRAY_SIZE(kvm_s390_fac_list_mask); } +/* available cpu features supported by kvm */ +static DECLARE_BITMAP(kvm_s390_available_cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS); + static struct gmap_notifier gmap_notifier; debug_info_t *kvm_s390_dbf; @@ -677,6 +681,29 @@ out: return ret; } +static int kvm_s390_set_processor_feat(struct kvm *kvm, + struct kvm_device_attr *attr) +{ + struct kvm_s390_vm_cpu_feat data; + int ret = -EBUSY; + + if (copy_from_user(&data, (void __user *)attr->addr, sizeof(data))) + return -EFAULT; + if (!bitmap_subset((unsigned long *) data.feat, + kvm_s390_available_cpu_feat, + KVM_S390_VM_CPU_FEAT_NR_BITS)) + return -EINVAL; + + mutex_lock(&kvm->lock); + if (!atomic_read(&kvm->online_vcpus)) { + bitmap_copy(kvm->arch.cpu_feat, (unsigned long *) data.feat, + KVM_S390_VM_CPU_FEAT_NR_BITS); + ret = 0; + } + mutex_unlock(&kvm->lock); + return ret; +} + static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) { int ret = -ENXIO; @@ -685,6 +712,9 @@ static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) case KVM_S390_VM_CPU_PROCESSOR: ret = kvm_s390_set_processor(kvm, attr); break; + case KVM_S390_VM_CPU_PROCESSOR_FEAT: + ret = kvm_s390_set_processor_feat(kvm, attr); + break; } return ret; } @@ -733,6 +763,31 @@ out: return ret; } +static int kvm_s390_get_processor_feat(struct kvm *kvm, + struct kvm_device_attr *attr) +{ + struct kvm_s390_vm_cpu_feat data; + + bitmap_copy((unsigned long *) data.feat, kvm->arch.cpu_feat, + KVM_S390_VM_CPU_FEAT_NR_BITS); + if (copy_to_user((void __user *)attr->addr, &data, sizeof(data))) + return -EFAULT; + return 0; +} + +static int kvm_s390_get_machine_feat(struct kvm *kvm, + struct kvm_device_attr *attr) +{ + struct kvm_s390_vm_cpu_feat data; + + bitmap_copy((unsigned long *) data.feat, + kvm_s390_available_cpu_feat, + KVM_S390_VM_CPU_FEAT_NR_BITS); + if (copy_to_user((void __user *)attr->addr, &data, sizeof(data))) + return -EFAULT; + return 0; +} + static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) { int ret = -ENXIO; @@ -744,6 +799,12 @@ static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr) case KVM_S390_VM_CPU_MACHINE: ret = kvm_s390_get_machine(kvm, attr); break; + case KVM_S390_VM_CPU_PROCESSOR_FEAT: + ret = kvm_s390_get_processor_feat(kvm, attr); + break; + case KVM_S390_VM_CPU_MACHINE_FEAT: + ret = kvm_s390_get_machine_feat(kvm, attr); + break; } return ret; } @@ -827,6 +888,8 @@ static int kvm_s390_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr) switch (attr->attr) { case KVM_S390_VM_CPU_PROCESSOR: case KVM_S390_VM_CPU_MACHINE: + case KVM_S390_VM_CPU_PROCESSOR_FEAT: + case KVM_S390_VM_CPU_MACHINE_FEAT: ret = 0; break; default: diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index c5ec4d31e5e3..52aa47e112d8 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -175,6 +175,12 @@ static inline int set_kvm_facility(u64 *fac_list, unsigned long nr) return 0; } +static inline int test_kvm_cpu_feat(struct kvm *kvm, unsigned long nr) +{ + WARN_ON_ONCE(nr >= KVM_S390_VM_CPU_FEAT_NR_BITS); + return test_bit_inv(nr, kvm->arch.cpu_feat); +} + /* are cpu states controlled by user space */ static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm) { |