diff mbox series

[v10,097/108] KVM: TDX: Handle TDX PV MMIO hypercall

Message ID	24003e50e3424cbf28518dbfc7d5a9da72482316.1667110240.git.isaku.yamahata@intel.com
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini <pbonzini@redhat.com>, erdemaktas@google.com, Sean Christopherson <seanjc@google.com>, Sagi Shahar <sagis@google.com>, David Matlack <dmatlack@google.com>, Sean Christopherson <sean.j.christopherson@intel.com> Subject: [PATCH v10 097/108] KVM: TDX: Handle TDX PV MMIO hypercall Date: Sat, 29 Oct 2022 23:23:38 -0700 Message-Id: <24003e50e3424cbf28518dbfc7d5a9da72482316.1667110240.git.isaku.yamahata@intel.com> In-Reply-To: <cover.1667110240.git.isaku.yamahata@intel.com> References: <cover.1667110240.git.isaku.yamahata@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	KVM TDX basic feature support \| [v10,000/108] KVM TDX basic feature support [v10,001/108] KVM: VMX: Move out vmx_x86_ops to 'main.c' to wrap VMX and TDX [v10,002/108] KVM: x86: Refactor KVM VMX module init/exit functions [v10,003/108] KVM: TDX: Add placeholders for TDX VM/vcpu structure [v10,004/108] x86/virt/tdx: Add a helper function to return system wide info about TDX module [v10,005/108] KVM: TDX: Initialize the TDX module when loading the KVM intel kernel module [v10,006/108] KVM: x86: Introduce vm_type to differentiate default VMs from confidential VMs [v10,007/108] KVM: TDX: Make TDX VM type supported [v10,008/108,MARKER] The start of TDX KVM patch series: TDX architectural definitions [v10,009/108] KVM: TDX: Define TDX architectural definitions [v10,010/108] KVM: TDX: Add TDX "architectural" error codes [v10,011/108] KVM: TDX: Add C wrapper functions for SEAMCALLs to the TDX module [v10,012/108] KVM: TDX: Add helper functions to print TDX SEAMCALL error [v10,013/108,MARKER] The start of TDX KVM patch series: TD VM creation/destruction [v10,014/108] KVM: TDX: Stub in tdx.h with structs, accessors, and VMCS helpers [v10,015/108] x86/cpu: Add helper functions to allocate/free TDX private host key id [v10,016/108] KVM: TDX: create/destroy VM structure [v10,017/108] KVM: TDX: Refuse to unplug the last cpu on the package [v10,018/108] KVM: TDX: x86: Add ioctl to get TDX systemwide parameters [v10,019/108] KVM: TDX: Add place holder for TDX VM specific mem_enc_op ioctl [v10,020/108] KVM: Support KVM_CAP_MAX_VCPUS for KVM_ENABLE_CAP [v10,021/108] KVM: TDX: initialize VM with TDX specific parameters [v10,022/108] KVM: TDX: Make pmu_intel.c ignore guest TD case [v10,023/108,MARKER] The start of TDX KVM patch series: TD vcpu creation/destruction [v10,024/108] KVM: TDX: allocate/free TDX vcpu structure [v10,025/108] KVM: TDX: Do TDX specific vcpu initialization [v10,026/108] KVM: TDX: Use private memory for TDX [v10,027/108,MARKER] The start of TDX KVM patch series: KVM MMU GPA shared bits [v10,028/108] KVM: x86/mmu: introduce config for PRIVATE KVM MMU [v10,029/108] KVM: x86/mmu: Add address conversion functions for TDX shared bit of GPA [v10,030/108,MARKER] The start of TDX KVM patch series: KVM TDP refactoring for TDX [v10,031/108] KVM: x86/mmu: Replace hardcoded value 0 for the initial value for SPTE [v10,032/108] KVM: x86/mmu: Make sync_page not use hard-coded 0 as the initial SPTE value [v10,033/108] KVM: x86/mmu: Allow non-zero value for non-present SPTE and removed SPTE [v10,034/108] KVM: x86/mmu: Add Suppress VE bit to shadow_mmio_{value, mask} [v10,035/108] KVM: x86/mmu: Track shadow MMIO value on a per-VM basis [v10,036/108] KVM: TDX: Enable mmio spte caching always for TDX [v10,037/108] KVM: x86/mmu: Disallow fast page fault on private GPA [v10,038/108] KVM: x86/mmu: Allow per-VM override of the TDP max page level [v10,039/108] KVM: VMX: Introduce test mode related to EPT violation VE [v10,040/108,MARKER] The start of TDX KVM patch series: KVM TDP MMU hooks [v10,041/108] KVM: x86/tdp_mmu: refactor kvm_tdp_mmu_map() [v10,042/108] KVM: x86/tdp_mmu: Init role member of struct kvm_mmu_page at allocation [v10,043/108] KVM: x86/mmu: Require TDP MMU for TDX [v10,044/108] KVM: x86/mmu: Add a new is_private member for union kvm_mmu_page_role [v10,045/108] KVM: x86/mmu: Add a private pointer to struct kvm_mmu_page [v10,046/108] KVM: Add flags to struct kvm_gfn_range [v10,047/108] KVM: x86/tdp_mmu: Don't zap private pages for unsupported cases [v10,048/108] KVM: x86/tdp_mmu: Make handle_changed_spte() return value [v10,049/108] KVM: x86/tdp_mmu: Support TDX private mapping for TDP MMU [v10,050/108,MARKER] The start of TDX KVM patch series: TDX EPT violation [v10,051/108] KVM: x86/mmu: Disallow dirty logging for x86 TDX [v10,052/108] KVM: x86/tdp_mmu: Ignore unsupported mmu operation on private GFNs [v10,053/108] KVM: VMX: Split out guts of EPT violation to common/exposed function [v10,054/108] KVM: VMX: Move setting of EPT MMU masks to common VT-x code [v10,055/108] KVM: TDX: Add load_mmu_pgd method for TDX [v10,056/108] KVM: TDX: don't request KVM_REQ_APIC_PAGE_RELOAD [v10,057/108] KVM: x86/VMX: introduce vmx tlb_remote_flush and tlb_remote_flush_with_range [v10,058/108] KVM: TDX: TDP MMU TDX support [v10,059/108,MARKER] The start of TDX KVM patch series: KVM TDP MMU MapGPA [v10,060/108] KVM: Add functions to set GFN to private or shared [v10,061/108] KVM: x86/mmu: Introduce kvm_mmu_map_tdp_page() for use by TDX [v10,062/108] KVM: x86/tdp_mmu: implement MapGPA hypercall for TDX [v10,063/108,MARKER] The start of TDX KVM patch series: TD finalization [v10,064/108] KVM: TDX: Create initial guest memory [v10,065/108] KVM: TDX: Finalize VM initialization [v10,066/108,MARKER] The start of TDX KVM patch series: TD vcpu enter/exit [v10,067/108] KVM: TDX: Add helper assembly function to TDX vcpu [v10,068/108] KVM: TDX: Implement TDX vcpu enter/exit path [v10,069/108] KVM: TDX: vcpu_run: save/restore host state(host kernel gs) [v10,070/108] KVM: TDX: restore host xsave state when exit from the guest TD [v10,071/108] KVM: x86: Allow to update cached values in kvm_user_return_msrs w/o wrmsr [v10,072/108] KVM: TDX: restore user ret MSRs [v10,073/108,MARKER] The start of TDX KVM patch series: TD vcpu exits/interrupts/hypercalls [v10,074/108] KVM: TDX: complete interrupts after tdexit [v10,075/108] KVM: TDX: restore debug store when TD exit [v10,076/108] KVM: TDX: handle vcpu migration over logical processor [v10,077/108] KVM: x86: Add a switch_db_regs flag to handle TDX's auto-switched behavior [v10,078/108] KVM: TDX: Add support for find pending IRQ in a protected local APIC [v10,079/108] KVM: x86: Assume timer IRQ was injected if APIC state is proteced [v10,080/108] KVM: TDX: remove use of struct vcpu_vmx from posted_interrupt.c [v10,081/108] KVM: TDX: Implement interrupt injection [v10,082/108] KVM: TDX: Implements vcpu request_immediate_exit [v10,083/108] KVM: TDX: Implement methods to inject NMI [v10,084/108] KVM: VMX: Modify NMI and INTR handlers to take intr_info as function argument [v10,085/108] KVM: VMX: Move NMI/exception handler to common helper [v10,086/108] KVM: x86: Split core of hypercall emulation to helper function [v10,087/108] KVM: TDX: Add a place holder to handle TDX VM exit [v10,088/108] KVM: TDX: Retry seamcall when TDX_OPERAND_BUSY with operand SEPT [v10,089/108] KVM: TDX: handle EXIT_REASON_OTHER_SMI [v10,090/108] KVM: TDX: handle ept violation/misconfig exit [v10,091/108] KVM: TDX: handle EXCEPTION_NMI and EXTERNAL_INTERRUPT [v10,092/108] KVM: TDX: Add a place holder for handler of TDX hypercalls (TDG.VP.VMCALL) [v10,093/108] KVM: TDX: handle KVM hypercall with TDG.VP.VMCALL [v10,094/108] KVM: TDX: Handle TDX PV CPUID hypercall [v10,095/108] KVM: TDX: Handle TDX PV HLT hypercall [v10,096/108] KVM: TDX: Handle TDX PV port io hypercall [v10,097/108] KVM: TDX: Handle TDX PV MMIO hypercall [v10,098/108] KVM: TDX: Implement callbacks for MSR operations for TDX [v10,099/108] KVM: TDX: Handle TDX PV rdmsr/wrmsr hypercall [v10,100/108] KVM: TDX: Handle TDX PV report fatal error hypercall [v10,101/108] KVM: TDX: Handle TDX PV map_gpa hypercall [v10,102/108] KVM: TDX: Handle TDG.VP.VMCALL<GetTdVmCallInfo> hypercall [v10,103/108] KVM: TDX: Silently discard SMI request [v10,104/108] KVM: TDX: Silently ignore INIT/SIPI [v10,105/108] KVM: TDX: Add methods to ignore accesses to CPU state [v10,106/108] Documentation/virt/kvm: Document on Trust Domain Extensions(TDX) [v10,107/108] KVM: x86: design documentation on TDX support of x86 KVM TDP MMU [v10,108/108,MARKER] the end of (the first phase of) TDX KVM patch series

Commit Message

Isaku Yamahata Oct. 30, 2022, 6:23 a.m. UTC

  From: Sean Christopherson <sean.j.christopherson@intel.com>

Export kvm_io_bus_read and kvm_mmio tracepoint and wire up TDX PV MMIO
hypercall to the KVM backend functions.

kvm_io_bus_read/write() searches KVM device emulated in kernel of the given
MMIO address and emulates the MMIO.  As TDX PV MMIO also needs it, export
kvm_io_bus_read().  kvm_io_bus_write() is already exported.  TDX PV MMIO
emulates some of MMIO itself.  To add trace point consistently with x86
kvm, export kvm_mmio tracepoint.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/vmx/tdx.c | 114 +++++++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/x86.c     |   1 +
 virt/kvm/kvm_main.c    |   2 +
 3 files changed, 117 insertions(+)

diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 69a3e7007e83..50e9352464a9 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -921,6 +921,118 @@  static int tdx_emulate_io(struct kvm_vcpu *vcpu)
 	return ret;
 }
 
+static int tdx_complete_mmio(struct kvm_vcpu *vcpu)
+{
+	unsigned long val = 0;
+	gpa_t gpa;
+	int size;
+
+	KVM_BUG_ON(vcpu->mmio_needed != 1, vcpu->kvm);
+	vcpu->mmio_needed = 0;
+
+	if (!vcpu->mmio_is_write) {
+		gpa = vcpu->mmio_fragments[0].gpa;
+		size = vcpu->mmio_fragments[0].len;
+
+		memcpy(&val, vcpu->run->mmio.data, size);
+		tdvmcall_set_return_val(vcpu, val);
+		trace_kvm_mmio(KVM_TRACE_MMIO_READ, size, gpa, &val);
+	}
+	return 1;
+}
+
+static inline int tdx_mmio_write(struct kvm_vcpu *vcpu, gpa_t gpa, int size,
+				 unsigned long val)
+{
+	if (kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, gpa, size, &val) &&
+	    kvm_io_bus_write(vcpu, KVM_MMIO_BUS, gpa, size, &val))
+		return -EOPNOTSUPP;
+
+	trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, size, gpa, &val);
+	return 0;
+}
+
+static inline int tdx_mmio_read(struct kvm_vcpu *vcpu, gpa_t gpa, int size)
+{
+	unsigned long val;
+
+	if (kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev, gpa, size, &val) &&
+	    kvm_io_bus_read(vcpu, KVM_MMIO_BUS, gpa, size, &val))
+		return -EOPNOTSUPP;
+
+	tdvmcall_set_return_val(vcpu, val);
+	trace_kvm_mmio(KVM_TRACE_MMIO_READ, size, gpa, &val);
+	return 0;
+}
+
+static int tdx_emulate_mmio(struct kvm_vcpu *vcpu)
+{
+	struct kvm_memory_slot *slot;
+	int size, write, r;
+	unsigned long val;
+	gpa_t gpa;
+
+	KVM_BUG_ON(vcpu->mmio_needed, vcpu->kvm);
+
+	size = tdvmcall_a0_read(vcpu);
+	write = tdvmcall_a1_read(vcpu);
+	gpa = tdvmcall_a2_read(vcpu);
+	val = write ? tdvmcall_a3_read(vcpu) : 0;
+
+	if (size != 1 && size != 2 && size != 4 && size != 8)
+		goto error;
+	if (write != 0 && write != 1)
+		goto error;
+
+	/* Strip the shared bit, allow MMIO with and without it set. */
+	gpa = gpa & ~gfn_to_gpa(kvm_gfn_shared_mask(vcpu->kvm));
+
+	if (size > 8u || ((gpa + size - 1) ^ gpa) & PAGE_MASK)
+		goto error;
+
+	slot = kvm_vcpu_gfn_to_memslot(vcpu, gpa_to_gfn(gpa));
+	if (slot && !(slot->flags & KVM_MEMSLOT_INVALID))
+		goto error;
+
+	if (!kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, gpa, 0, NULL)) {
+		trace_kvm_fast_mmio(gpa);
+		return 1;
+	}
+
+	if (write)
+		r = tdx_mmio_write(vcpu, gpa, size, val);
+	else
+		r = tdx_mmio_read(vcpu, gpa, size);
+	if (!r) {
+		/* Kernel completed device emulation. */
+		tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+		return 1;
+	}
+
+	/* Request the device emulation to userspace device model. */
+	vcpu->mmio_needed = 1;
+	vcpu->mmio_is_write = write;
+	vcpu->arch.complete_userspace_io = tdx_complete_mmio;
+
+	vcpu->run->mmio.phys_addr = gpa;
+	vcpu->run->mmio.len = size;
+	vcpu->run->mmio.is_write = write;
+	vcpu->run->exit_reason = KVM_EXIT_MMIO;
+
+	if (write) {
+		memcpy(vcpu->run->mmio.data, &val, size);
+	} else {
+		vcpu->mmio_fragments[0].gpa = gpa;
+		vcpu->mmio_fragments[0].len = size;
+		trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, size, gpa, NULL);
+	}
+	return 0;
+
+error:
+	tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+	return 1;
+}
+
 static int handle_tdvmcall(struct kvm_vcpu *vcpu)
 {
 	if (tdvmcall_exit_type(vcpu))
@@ -933,6 +1045,8 @@  static int handle_tdvmcall(struct kvm_vcpu *vcpu)
 		return tdx_emulate_hlt(vcpu);
 	case EXIT_REASON_IO_INSTRUCTION:
 		return tdx_emulate_io(vcpu);
+	case EXIT_REASON_EPT_VIOLATION:
+		return tdx_emulate_mmio(vcpu);
 	default:
 		break;
 	}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fad5108dff1e..2eacc4929d5d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -13919,6 +13919,7 @@  bool kvm_arch_has_private_mem(struct kvm *kvm)
 
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_mmio);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f0e77b65939b..6953da8b74d3 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2815,6 +2815,7 @@  struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot);
 
 bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 {
@@ -5822,6 +5823,7 @@  int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
 	r = __kvm_io_bus_read(vcpu, bus, &range, val);
 	return r < 0 ? r : 0;
 }
+EXPORT_SYMBOL_GPL(kvm_io_bus_read);
 
 /* Caller must hold slots_lock. */
 int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,