Commit 30d583fd authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: x86: move all vcpu->arch.pio* setup in emulator_pio_in_out() 



For now, this is basically an excuse to add back the void* argument to
the function, while removing some knowledge of vcpu->arch.pio* from
its callers.  The WARN that vcpu->arch.pio.count is zero is also
extended to OUT operations.

The vcpu->arch.pio* fields still need to be filled even when the PIO is
handled in-kernel as __emulator_pio_in() is always followed by
complete_emulator_pio_in().  But after fixing that, it will be possible to
to only populate the vcpu->arch.pio* fields on userspace exits.

No functional change intended.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 35ab3b77

arch/x86/kvm/trace.h

+1 −1
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ TRACE_EVENT(kvm_xen_hypercall, 


TRACE_EVENT(kvm_pio,

	TP_PROTO(unsigned int rw, unsigned int port, unsigned int size,

		 unsigned int count, void *data),

		 unsigned int count, const void *data),

	TP_ARGS(rw, port, size, count, data),



	TP_STRUCT__entry(

arch/x86/kvm/x86.c

+13 −8
Original line number Diff line number Diff line
@@ -7576,17 +7576,25 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, 
}



static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size,

			       unsigned short port,

			       unsigned short port, void *data,

			       unsigned int count, bool in)

{

	void *data = vcpu->arch.pio_data;

	unsigned i;

	int r;



	WARN_ON_ONCE(vcpu->arch.pio.count);

	vcpu->arch.pio.port = port;

	vcpu->arch.pio.in = in;

	vcpu->arch.pio.count = count;

	vcpu->arch.pio.size = size;

	if (in) {

		/* The buffer is only used in complete_emulator_pio_in().  */

		WARN_ON(data);

		memset(vcpu->arch.pio_data, 0, size * count);

	} else {

		memcpy(vcpu->arch.pio_data, data, size * count);

	}

	data = vcpu->arch.pio_data;



	for (i = 0; i < count; i++) {

		if (in)
@@ -7623,9 +7631,7 @@ static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size, 
static int __emulator_pio_in(struct kvm_vcpu *vcpu, int size,

			     unsigned short port, unsigned int count)

{

	WARN_ON(vcpu->arch.pio.count);

	memset(vcpu->arch.pio_data, 0, size * count);

	return emulator_pio_in_out(vcpu, size, port, count, true);

	return emulator_pio_in_out(vcpu, size, port, NULL, count, true);

}



static void complete_emulator_pio_in(struct kvm_vcpu *vcpu, void *val)
@@ -7674,9 +7680,8 @@ static int emulator_pio_out(struct kvm_vcpu *vcpu, int size, 
{

	int ret;



	memcpy(vcpu->arch.pio_data, val, size * count);

	trace_kvm_pio(KVM_PIO_OUT, port, size, count, vcpu->arch.pio_data);

	ret = emulator_pio_in_out(vcpu, size, port, count, false);

	trace_kvm_pio(KVM_PIO_OUT, port, size, count, val);

	ret = emulator_pio_in_out(vcpu, size, port, (void *)val, count, false);

	if (ret)

                vcpu->arch.pio.count = 0;