From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> Introduce a helper to directly (pun intended) fault-in a TDP page without having to go through the full page fault path. This allows TDX to get the resulting pfn and also allows the RET_PF_* enums to stay in mmu.c where they belong. Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> --- v14 -> v15: - Remove loop in kvm_mmu_map_tdp_page() and return error code based on RET_FP_xxx value to avoid potential infinite loop. The caller should loop on -EAGAIN instead now. --- arch/x86/kvm/mmu.h | 3 +++ arch/x86/kvm/mmu/mmu.c | 58 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 61 insertions(+) diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index 801e3d6b572d..1bca16217da3 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -174,6 +174,9 @@ static inline void kvm_mmu_refresh_passthrough_bits(struct kvm_vcpu *vcpu, __kvm_mmu_refresh_passthrough_bits(vcpu, mmu); } +int kvm_mmu_map_tdp_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, + int max_level); + /* * Check if a given access (described through the I/D, W/R and U/S bits of a * page fault error code pfec) causes a permission fault with the given PTE diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 4e9343e759f6..7ef66d8a785b 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4673,6 +4673,64 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) return direct_page_fault(vcpu, fault); } +int kvm_mmu_map_tdp_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, + int max_level) +{ + int r; + struct kvm_page_fault fault = (struct kvm_page_fault) { + .addr = gpa, + .error_code = error_code, + .exec = error_code & PFERR_FETCH_MASK, + .write = error_code & PFERR_WRITE_MASK, + .present = error_code & PFERR_PRESENT_MASK, + .rsvd = error_code & PFERR_RSVD_MASK, + .user = error_code & PFERR_USER_MASK, + .prefetch = false, + .is_tdp = true, + .is_private = error_code & PFERR_GUEST_ENC_MASK, + .nx_huge_page_workaround_enabled = is_nx_huge_page_enabled(vcpu->kvm), + }; + + WARN_ON_ONCE(!vcpu->arch.mmu->root_role.direct); + fault.gfn = gpa_to_gfn(fault.addr) & ~kvm_gfn_shared_mask(vcpu->kvm); + fault.slot = kvm_vcpu_gfn_to_memslot(vcpu, fault.gfn); + + r = mmu_topup_memory_caches(vcpu, false); + if (r) + return r; + + fault.max_level = max_level; + fault.req_level = PG_LEVEL_4K; + fault.goal_level = PG_LEVEL_4K; + +#ifdef CONFIG_X86_64 + if (tdp_mmu_enabled) + r = kvm_tdp_mmu_page_fault(vcpu, &fault); + else +#endif + r = direct_page_fault(vcpu, &fault); + + if (is_error_noslot_pfn(fault.pfn) || vcpu->kvm->vm_bugged) + return -EFAULT; + + switch (r) { + case RET_PF_RETRY: + return -EAGAIN; + + case RET_PF_FIXED: + case RET_PF_SPURIOUS: + return 0; + + case RET_PF_CONTINUE: + case RET_PF_EMULATE: + case RET_PF_INVALID: + case RET_PF_USER: + default: + return -EIO; + } +} +EXPORT_SYMBOL_GPL(kvm_mmu_map_tdp_page); + static void nonpaging_init_context(struct kvm_mmu *context) { context->page_fault = nonpaging_page_fault; -- 2.25.1