diff options
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | arch/arm64/include/asm/mte-def.h | 1 | ||||
| -rw-r--r-- | arch/arm64/include/uapi/asm/kvm.h | 11 | ||||
| -rw-r--r-- | arch/arm64/kvm/arm.c | 7 | ||||
| -rw-r--r-- | arch/arm64/kvm/guest.c | 82 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 1 |
6 files changed, 105 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 74a7447a83a1..c93a7198c242 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -730,6 +730,9 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); +long kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, + struct kvm_arm_copy_mte_tags *copy_tags); + /* Guest/host FPSIMD coordination helpers */ int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/include/asm/mte-def.h b/arch/arm64/include/asm/mte-def.h index cf241b0f0a42..626d359b396e 100644 --- a/arch/arm64/include/asm/mte-def.h +++ b/arch/arm64/include/asm/mte-def.h @@ -7,6 +7,7 @@ #define MTE_GRANULE_SIZE UL(16) #define MTE_GRANULE_MASK (~(MTE_GRANULE_SIZE - 1)) +#define MTE_GRANULES_PER_PAGE (PAGE_SIZE / MTE_GRANULE_SIZE) #define MTE_TAG_SHIFT 56 #define MTE_TAG_SIZE 4 #define MTE_TAG_MASK GENMASK((MTE_TAG_SHIFT + (MTE_TAG_SIZE - 1)), MTE_TAG_SHIFT) diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 24223adae150..b3edde68bc3e 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -184,6 +184,17 @@ struct kvm_vcpu_events { __u32 reserved[12]; }; +struct kvm_arm_copy_mte_tags { + __u64 guest_ipa; + __u64 length; + void __user *addr; + __u64 flags; + __u64 reserved[2]; +}; + +#define KVM_ARM_TAGS_TO_GUEST 0 +#define KVM_ARM_TAGS_FROM_GUEST 1 + /* If you need to interpret the index values, here is the key: */ #define KVM_REG_ARM_COPROC_MASK 0x000000000FFF0000 #define KVM_REG_ARM_COPROC_SHIFT 16 diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 28ce26a68f09..511f3716fe33 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1359,6 +1359,13 @@ long kvm_arch_vm_ioctl(struct file *filp, return 0; } + case KVM_ARM_MTE_COPY_TAGS: { + struct kvm_arm_copy_mte_tags copy_tags; + + if (copy_from_user(©_tags, argp, sizeof(copy_tags))) + return -EFAULT; + return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); + } default: return -EINVAL; } diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 5cb4a1cd5603..4ddb20017b2f 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -995,3 +995,85 @@ int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, return ret; } + +long kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, + struct kvm_arm_copy_mte_tags *copy_tags) +{ + gpa_t guest_ipa = copy_tags->guest_ipa; + size_t length = copy_tags->length; + void __user *tags = copy_tags->addr; + gpa_t gfn; + bool write = !(copy_tags->flags & KVM_ARM_TAGS_FROM_GUEST); + int ret = 0; + + if (!kvm_has_mte(kvm)) + return -EINVAL; + + if (copy_tags->reserved[0] || copy_tags->reserved[1]) + return -EINVAL; + + if (copy_tags->flags & ~KVM_ARM_TAGS_FROM_GUEST) + return -EINVAL; + + if (length & ~PAGE_MASK || guest_ipa & ~PAGE_MASK) + return -EINVAL; + + gfn = gpa_to_gfn(guest_ipa); + + mutex_lock(&kvm->slots_lock); + + while (length > 0) { + kvm_pfn_t pfn = gfn_to_pfn_prot(kvm, gfn, write, NULL); + void *maddr; + unsigned long num_tags; + struct page *page; + + if (is_error_noslot_pfn(pfn)) { + ret = -EFAULT; + goto out; + } + + page = pfn_to_online_page(pfn); + if (!page) { + /* Reject ZONE_DEVICE memory */ + ret = -EFAULT; + goto out; + } + maddr = page_address(page); + + if (!write) { + if (test_bit(PG_mte_tagged, &page->flags)) + num_tags = mte_copy_tags_to_user(tags, maddr, + MTE_GRANULES_PER_PAGE); + else + /* No tags in memory, so write zeros */ + num_tags = MTE_GRANULES_PER_PAGE - + clear_user(tags, MTE_GRANULES_PER_PAGE); + kvm_release_pfn_clean(pfn); + } else { + num_tags = mte_copy_tags_from_user(maddr, tags, + MTE_GRANULES_PER_PAGE); + kvm_release_pfn_dirty(pfn); + } + + if (num_tags != MTE_GRANULES_PER_PAGE) { + ret = -EFAULT; + goto out; + } + + /* Set the flag after checking the write completed fully */ + if (write) + set_bit(PG_mte_tagged, &page->flags); + + gfn++; + tags += num_tags; + length -= PAGE_SIZE; + } + +out: + mutex_unlock(&kvm->slots_lock); + /* If some data has been copied report the number of bytes copied */ + if (length != copy_tags->length) + return copy_tags->length - length; + return ret; +} diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index d4da58ddcad7..da1edd2b4046 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1429,6 +1429,7 @@ struct kvm_s390_ucas_mapping { /* Available with KVM_CAP_PMU_EVENT_FILTER */ #define KVM_SET_PMU_EVENT_FILTER _IOW(KVMIO, 0xb2, struct kvm_pmu_event_filter) #define KVM_PPC_SVM_OFF _IO(KVMIO, 0xb3) +#define KVM_ARM_MTE_COPY_TAGS _IOR(KVMIO, 0xb4, struct kvm_arm_copy_mte_tags) /* ioctl for vm fd */ #define KVM_CREATE_DEVICE _IOWR(KVMIO, 0xe0, struct kvm_create_device) |