diff options
| -rw-r--r-- | arch/x86/include/uapi/asm/kvm.h | 9 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/tdx.c | 144 |
2 files changed, 153 insertions, 0 deletions
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h index cd55484e3f0c..ee1b517351a3 100644 --- a/arch/x86/include/uapi/asm/kvm.h +++ b/arch/x86/include/uapi/asm/kvm.h @@ -932,6 +932,7 @@ enum kvm_tdx_cmd_id { KVM_TDX_CAPABILITIES = 0, KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU, + KVM_TDX_INIT_MEM_REGION, KVM_TDX_GET_CPUID, KVM_TDX_CMD_NR_MAX, @@ -987,4 +988,12 @@ struct kvm_tdx_init_vm { struct kvm_cpuid2 cpuid; }; +#define KVM_TDX_MEASURE_MEMORY_REGION _BITULL(0) + +struct kvm_tdx_init_mem_region { + __u64 source_addr; + __u64 gpa; + __u64 nr_pages; +}; + #endif /* _ASM_X86_KVM_H */ diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 3e8c99d731d6..6132eac61ed5 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#include <linux/cleanup.h> #include <linux/cpu.h> #include <asm/cpufeature.h> #include <linux/misc_cgroup.h> @@ -10,6 +11,7 @@ #include "tdx.h" #include "vmx.h" #include "mmu/spte.h" +#include "common.h" #pragma GCC poison to_vmx @@ -1606,6 +1608,145 @@ static int tdx_vcpu_init(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *cmd) return 0; } +struct tdx_gmem_post_populate_arg { + struct kvm_vcpu *vcpu; + __u32 flags; +}; + +static int tdx_gmem_post_populate(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, + void __user *src, int order, void *_arg) +{ + u64 error_code = PFERR_GUEST_FINAL_MASK | PFERR_PRIVATE_ACCESS; + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + struct tdx_gmem_post_populate_arg *arg = _arg; + struct kvm_vcpu *vcpu = arg->vcpu; + gpa_t gpa = gfn_to_gpa(gfn); + u8 level = PG_LEVEL_4K; + struct page *src_page; + int ret, i; + u64 err, entry, level_state; + + /* + * Get the source page if it has been faulted in. Return failure if the + * source page has been swapped out or unmapped in primary memory. + */ + ret = get_user_pages_fast((unsigned long)src, 1, 0, &src_page); + if (ret < 0) + return ret; + if (ret != 1) + return -ENOMEM; + + ret = kvm_tdp_map_page(vcpu, gpa, error_code, &level); + if (ret < 0) + goto out; + + /* + * The private mem cannot be zapped after kvm_tdp_map_page() + * because all paths are covered by slots_lock and the + * filemap invalidate lock. Check that they are indeed enough. + */ + if (IS_ENABLED(CONFIG_KVM_PROVE_MMU)) { + scoped_guard(read_lock, &kvm->mmu_lock) { + if (KVM_BUG_ON(!kvm_tdp_mmu_gpa_is_mapped(vcpu, gpa), kvm)) { + ret = -EIO; + goto out; + } + } + } + + ret = 0; + err = tdh_mem_page_add(&kvm_tdx->td, gpa, pfn_to_page(pfn), + src_page, &entry, &level_state); + if (err) { + ret = unlikely(tdx_operand_busy(err)) ? -EBUSY : -EIO; + goto out; + } + + if (arg->flags & KVM_TDX_MEASURE_MEMORY_REGION) { + for (i = 0; i < PAGE_SIZE; i += TDX_EXTENDMR_CHUNKSIZE) { + err = tdh_mr_extend(&kvm_tdx->td, gpa + i, &entry, + &level_state); + if (err) { + ret = -EIO; + break; + } + } + } + +out: + put_page(src_page); + return ret; +} + +static int tdx_vcpu_init_mem_region(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *cmd) +{ + struct vcpu_tdx *tdx = to_tdx(vcpu); + struct kvm *kvm = vcpu->kvm; + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + struct kvm_tdx_init_mem_region region; + struct tdx_gmem_post_populate_arg arg; + long gmem_ret; + int ret; + + if (tdx->state != VCPU_TD_STATE_INITIALIZED) + return -EINVAL; + + guard(mutex)(&kvm->slots_lock); + + /* Once TD is finalized, the initial guest memory is fixed. */ + if (kvm_tdx->state == TD_STATE_RUNNABLE) + return -EINVAL; + + if (cmd->flags & ~KVM_TDX_MEASURE_MEMORY_REGION) + return -EINVAL; + + if (copy_from_user(®ion, u64_to_user_ptr(cmd->data), sizeof(region))) + return -EFAULT; + + if (!PAGE_ALIGNED(region.source_addr) || !PAGE_ALIGNED(region.gpa) || + !region.nr_pages || + region.gpa + (region.nr_pages << PAGE_SHIFT) <= region.gpa || + !vt_is_tdx_private_gpa(kvm, region.gpa) || + !vt_is_tdx_private_gpa(kvm, region.gpa + (region.nr_pages << PAGE_SHIFT) - 1)) + return -EINVAL; + + kvm_mmu_reload(vcpu); + ret = 0; + while (region.nr_pages) { + if (signal_pending(current)) { + ret = -EINTR; + break; + } + + arg = (struct tdx_gmem_post_populate_arg) { + .vcpu = vcpu, + .flags = cmd->flags, + }; + gmem_ret = kvm_gmem_populate(kvm, gpa_to_gfn(region.gpa), + u64_to_user_ptr(region.source_addr), + 1, tdx_gmem_post_populate, &arg); + if (gmem_ret < 0) { + ret = gmem_ret; + break; + } + + if (gmem_ret != 1) { + ret = -EIO; + break; + } + + region.source_addr += PAGE_SIZE; + region.gpa += PAGE_SIZE; + region.nr_pages--; + + cond_resched(); + } + + if (copy_to_user(u64_to_user_ptr(cmd->data), ®ion, sizeof(region))) + ret = -EFAULT; + return ret; +} + int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm); @@ -1625,6 +1766,9 @@ int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) case KVM_TDX_INIT_VCPU: ret = tdx_vcpu_init(vcpu, &cmd); break; + case KVM_TDX_INIT_MEM_REGION: + ret = tdx_vcpu_init_mem_region(vcpu, &cmd); + break; case KVM_TDX_GET_CPUID: ret = tdx_vcpu_get_cpuid(vcpu, &cmd); break; |