[PATCH 5.14 107/169] KVM: SEV-ES: clean up kvm_sev_es_ins/outs

Greg Kroah-Hartman
2021-10-25T19:54:25Z

From: Paolo Bonzini <pbonzini@redhat.com>

commit ea724ea420aac58b41bc822d1aed6940b136b78d upstream.

A few very small cleanups to the functions, smushed together because
the patch is already very small like this:

- inline emulator_pio_in_emulated and emulator_pio_out_emulated,
since we already have the vCPU

- remove the data argument and pull setting vcpu->arch.sev_pio_data into
the caller

- remove unnecessary clearing of vcpu->arch.pio.count when
emulation is done by the kernel (and therefore vcpu->arch.pio.count
is already clear on exit from emulator_pio_in and emulator_pio_out).

No functional change intended.

Cc: stable@vger.kernel.org
Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest")
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/x86.c | 31 +++++++++++++++----------------
1 file changed, 15 insertions(+), 16 deletions(-)

--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12330,34 +12330,32 @@ static int complete_sev_es_emulated_ins(
}

static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size,
- unsigned int port, void *data, unsigned int count)
+ unsigned int port, unsigned int count)
{
- int ret;
+ int ret = emulator_pio_out(vcpu, size, port,
+ vcpu->arch.sev_pio_data, count);

- ret = emulator_pio_out_emulated(vcpu->arch.emulate_ctxt, size, port,
- data, count);
- if (ret)
+ if (ret) {
+ /* Emulation done by the kernel. */
return ret;
+ }

vcpu->arch.pio.count = 0;
-
return 0;
}

static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size,
- unsigned int port, void *data, unsigned int count)
+ unsigned int port, unsigned int count)
{
- int ret;
+ int ret = emulator_pio_in(vcpu, size, port,
+ vcpu->arch.sev_pio_data, count);

- ret = emulator_pio_in_emulated(vcpu->arch.emulate_ctxt, size, port,
- data, count);
if (ret) {
- vcpu->arch.pio.count = 0;
- } else {
- vcpu->arch.sev_pio_data = data;
- vcpu->arch.complete_userspace_io = complete_sev_es_emulated_ins;
+ /* Emulation done by the kernel. */
+ return ret;
}

+ vcpu->arch.complete_userspace_io = complete_sev_es_emulated_ins;
return 0;
}

@@ -12365,8 +12363,9 @@ int kvm_sev_es_string_io(struct kvm_vcpu
unsigned int port, void *data, unsigned int count,
int in)
{
- return in ? kvm_sev_es_ins(vcpu, size, port, data, count)
- : kvm_sev_es_outs(vcpu, size, port, data, count);
+ vcpu->arch.sev_pio_data = data;
+ return in ? kvm_sev_es_ins(vcpu, size, port, count)
+ : kvm_sev_es_outs(vcpu, size, port, count);
}
EXPORT_SYMBOL_GPL(kvm_sev_es_string_io);