This change adds handling of HVA ranges to copy contents to private memory while doing sev launch update data.
mem_attr array is updated during LAUNCH_UPDATE_DATA to ensure that encrypted memory is marked as private.
Signed-off-by: Vishal Annapurve vannapurve@google.com --- arch/x86/kvm/svm/sev.c | 99 ++++++++++++++++++++++++++++++++++++---- include/linux/kvm_host.h | 2 + virt/kvm/kvm_main.c | 39 ++++++++++------ 3 files changed, 116 insertions(+), 24 deletions(-)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 309bcdb2f929..673dca318cd4 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -492,23 +492,22 @@ static unsigned long get_num_contig_pages(unsigned long idx, return pages; }
-static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) +int sev_launch_update_shared_gfn_handler(struct kvm *kvm, + struct kvm_gfn_range *range, struct kvm_sev_cmd *argp) { unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; - struct kvm_sev_launch_update_data params; struct sev_data_launch_update_data data; struct page **inpages; int ret;
- if (!sev_guest(kvm)) - return -ENOTTY; - - if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) - return -EFAULT; + vaddr = gfn_to_hva_memslot(range->slot, range->start); + if (kvm_is_error_hva(vaddr)) { + pr_err("vaddr is erroneous 0x%lx\n", vaddr); + return -EINVAL; + }
- vaddr = params.uaddr; - size = params.len; + size = (range->end - range->start) << PAGE_SHIFT; vaddr_end = vaddr + size;
/* Lock the user memory. */ @@ -560,6 +559,88 @@ static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) return ret; }
+int sev_launch_update_priv_gfn_handler(struct kvm *kvm, + struct kvm_gfn_range *range, struct kvm_sev_cmd *argp) +{ + struct sev_data_launch_update_data data; + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + gfn_t gfn; + kvm_pfn_t pfn; + struct kvm_memory_slot *memslot = range->slot; + int ret = 0; + + data.reserved = 0; + data.handle = sev->handle; + + for (gfn = range->start; gfn < range->end; gfn++) { + int order; + void *kvaddr; + + ret = kvm_private_mem_get_pfn(memslot, + gfn, &pfn, &order); + if (ret) + return ret; + + kvaddr = pfn_to_kaddr(pfn); + if (!virt_addr_valid(kvaddr)) { + pr_err("Invalid kvaddr 0x%lx\n", (uint64_t)kvaddr); + ret = -EINVAL; + goto e_ret; + } + + ret = kvm_read_guest_page(kvm, gfn, kvaddr, 0, PAGE_SIZE); + if (ret) { + pr_err("guest read failed 0x%lx\n", ret); + goto e_ret; + } + + if (!this_cpu_has(X86_FEATURE_SME_COHERENT)) + clflush_cache_range(kvaddr, PAGE_SIZE); + + data.len = PAGE_SIZE; + data.address = __sme_set(pfn << PAGE_SHIFT); + ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); + if (ret) + goto e_ret; + + kvm_private_mem_put_pfn(memslot, pfn); + } + kvm_vm_set_region_attr(kvm, range->start, range->end, + true /* priv_attr */); + + return ret; + +e_ret: + kvm_private_mem_put_pfn(memslot, pfn); + return ret; +} + +int sev_launch_update_gfn_handler(struct kvm *kvm, + struct kvm_gfn_range *range, void *data) +{ + struct kvm_sev_cmd *argp = (struct kvm_sev_cmd *)data; + + if (kvm_slot_can_be_private(range->slot)) + return sev_launch_update_priv_gfn_handler(kvm, range, argp); + + return sev_launch_update_shared_gfn_handler(kvm, range, argp); +} + +static int sev_launch_update_data(struct kvm *kvm, + struct kvm_sev_cmd *argp) +{ + struct kvm_sev_launch_update_data params; + + if (!sev_guest(kvm)) + return -ENOTTY; + + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) + return -EFAULT; + + return kvm_vm_do_hva_range_op(kvm, params.uaddr, params.uaddr + params.len, + sev_launch_update_gfn_handler, argp); +} + static int sev_es_sync_vmsa(struct vcpu_svm *svm) { struct sev_es_save_area *save = svm->sev_es.vmsa; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index c860e6d6408d..5d0054e957b4 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -980,6 +980,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, void kvm_exit(void);
void kvm_get_kvm(struct kvm *kvm); +int kvm_vm_set_region_attr(struct kvm *kvm, unsigned long gfn_start, + unsigned long gfn_end, bool priv_attr); bool kvm_get_kvm_safe(struct kvm *kvm); void kvm_put_kvm(struct kvm *kvm); bool file_is_kvm(struct file *file); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 16cb9ab59143..9463737c2172 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -981,7 +981,7 @@ static int kvm_vm_populate_private_mem(struct kvm *kvm, unsigned long gfn_start, }
mutex_lock(&kvm->slots_lock); - for (gfn = gfn_start; gfn <= gfn_end; gfn++) { + for (gfn = gfn_start; gfn < gfn_end; gfn++) { int order; void *kvaddr;
@@ -1012,12 +1012,29 @@ static int kvm_vm_populate_private_mem(struct kvm *kvm, unsigned long gfn_start, } #endif
+int kvm_vm_set_region_attr(struct kvm *kvm, unsigned long gfn_start, + unsigned long gfn_end, bool priv_attr) +{ + int r; + void *entry; + unsigned long index; + + entry = priv_attr ? xa_mk_value(KVM_MEM_ATTR_PRIVATE) : NULL; + + for (index = gfn_start; index < gfn_end; index++) { + r = xa_err(xa_store(&kvm->mem_attr_array, index, entry, + GFP_KERNEL_ACCOUNT)); + if (r) + break; + } + + return r; +} + static int kvm_vm_ioctl_set_encrypted_region(struct kvm *kvm, unsigned int ioctl, struct kvm_enc_region *region) { unsigned long start, end; - unsigned long index; - void *entry; int r;
if (region->size == 0 || region->addr + region->size < region->addr) @@ -1026,22 +1043,14 @@ static int kvm_vm_ioctl_set_encrypted_region(struct kvm *kvm, unsigned int ioctl return -EINVAL;
start = region->addr >> PAGE_SHIFT; - end = (region->addr + region->size - 1) >> PAGE_SHIFT; - - entry = ioctl == KVM_MEMORY_ENCRYPT_REG_REGION ? - xa_mk_value(KVM_MEM_ATTR_PRIVATE) : NULL; - - for (index = start; index <= end; index++) { - r = xa_err(xa_store(&kvm->mem_attr_array, index, entry, - GFP_KERNEL_ACCOUNT)); - if (r) - break; - } + end = (region->addr + region->size) >> PAGE_SHIFT; + r = kvm_vm_set_region_attr(kvm, start, end, + (ioctl == KVM_MEMORY_ENCRYPT_REG_REGION));
kvm_zap_gfn_range(kvm, start, end + 1);
#ifdef CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING - if (!kvm->vm_entry_attempted && (ioctl == KVM_MEMORY_ENCRYPT_REG_REGION)) + if (!r && !kvm->vm_entry_attempted && (ioctl == KVM_MEMORY_ENCRYPT_REG_REGION)) r = kvm_vm_populate_private_mem(kvm, start, end); #endif