KVM: x86: Refactor I/O emulation helpers to provide vcpu-only variant

Add variants of the I/O helpers that take a vCPU instead of an emulation
context.  This will eventually allow KVM to limit use of the emulation
context to the full emulation path.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fa03f31..fbf68c3 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5904,11 +5904,9 @@ static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size,
        return 0;
 }
 
-static int emulator_pio_in_emulated(struct x86_emulate_ctxt *ctxt,
-                                   int size, unsigned short port, void *val,
-                                   unsigned int count)
+static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
+                          unsigned short port, void *val, unsigned int count)
 {
-       struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
        int ret;
 
        if (vcpu->arch.pio.count)
@@ -5928,17 +5926,30 @@ data_avail:
        return 0;
 }
 
-static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt,
-                                    int size, unsigned short port,
-                                    const void *val, unsigned int count)
+static int emulator_pio_in_emulated(struct x86_emulate_ctxt *ctxt,
+                                   int size, unsigned short port, void *val,
+                                   unsigned int count)
 {
-       struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
+       return emulator_pio_in(emul_to_vcpu(ctxt), size, port, val, count);
 
+}
+
+static int emulator_pio_out(struct kvm_vcpu *vcpu, int size,
+                           unsigned short port, const void *val,
+                           unsigned int count)
+{
        memcpy(vcpu->arch.pio_data, val, size * count);
        trace_kvm_pio(KVM_PIO_OUT, port, size, count, vcpu->arch.pio_data);
        return emulator_pio_in_out(vcpu, size, port, (void *)val, count, false);
 }
 
+static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt,
+                                    int size, unsigned short port,
+                                    const void *val, unsigned int count)
+{
+       return emulator_pio_out(emul_to_vcpu(ctxt), size, port, val, count);
+}
+
 static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg)
 {
        return kvm_x86_ops->get_segment_base(vcpu, seg);
@@ -6891,8 +6902,8 @@ static int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size,
                            unsigned short port)
 {
        unsigned long val = kvm_rax_read(vcpu);
-       int ret = emulator_pio_out_emulated(&vcpu->arch.emulate_ctxt,
-                                           size, port, &val, 1);
+       int ret = emulator_pio_out(vcpu, size, port, &val, 1);
+
        if (ret)
                return ret;
 
@@ -6928,11 +6939,10 @@ static int complete_fast_pio_in(struct kvm_vcpu *vcpu)
        val = (vcpu->arch.pio.size < 4) ? kvm_rax_read(vcpu) : 0;
 
        /*
-        * Since vcpu->arch.pio.count == 1 let emulator_pio_in_emulated perform
+        * Since vcpu->arch.pio.count == 1 let emulator_pio_in perform
         * the copy and tracing
         */
-       emulator_pio_in_emulated(&vcpu->arch.emulate_ctxt, vcpu->arch.pio.size,
-                                vcpu->arch.pio.port, &val, 1);
+       emulator_pio_in(vcpu, vcpu->arch.pio.size, vcpu->arch.pio.port, &val, 1);
        kvm_rax_write(vcpu, val);
 
        return kvm_skip_emulated_instruction(vcpu);
@@ -6947,8 +6957,7 @@ static int kvm_fast_pio_in(struct kvm_vcpu *vcpu, int size,
        /* For size less than 4 we merge, else we zero extend */
        val = (size < 4) ? kvm_rax_read(vcpu) : 0;
 
-       ret = emulator_pio_in_emulated(&vcpu->arch.emulate_ctxt, size, port,
-                                      &val, 1);
+       ret = emulator_pio_in(vcpu, size, port, &val, 1);
        if (ret) {
                kvm_rax_write(vcpu, val);
                return ret;