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authorPaolo Bonzini <pbonzini@redhat.com>2021-10-22 08:07:19 -0400
committerPaolo Bonzini <pbonzini@redhat.com>2022-06-24 12:53:50 -0400
commit30d583fd4e1ecafa8642f9f74e102876b4aeb733 (patch)
treeb510b3c479fd61387424940804f2b50f87877e9c /arch/x86/kvm
parentKVM: x86: drop PIO from unregistered devices (diff)
downloadlinux-dev-30d583fd4e1ecafa8642f9f74e102876b4aeb733.tar.xz
linux-dev-30d583fd4e1ecafa8642f9f74e102876b4aeb733.zip
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: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r--arch/x86/kvm/trace.h2
-rw-r--r--arch/x86/kvm/x86.c21
2 files changed, 14 insertions, 9 deletions
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index bc85622e28b2..2120d7c060a9 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -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(
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5a56d39bd81f..368d0d4d56ff 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7576,17 +7576,25 @@ emul_write:
}
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 @@ userspace_io:
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;