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| author | Paolo Bonzini <pbonzini@redhat.com> | 2021-10-22 08:07:19 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-06-24 12:53:50 -0400 |
| commit | 30d583fd4e1ecafa8642f9f74e102876b4aeb733 (patch) | |
| tree | b510b3c479fd61387424940804f2b50f87877e9c | |
| parent | 35ab3b77a0ae76246dd2666d4f8190c824392fb4 (diff) | |
| download | lwn-30d583fd4e1ecafa8642f9f74e102876b4aeb733.tar.gz lwn-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>
| -rw-r--r-- | arch/x86/kvm/trace.h | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 21 |
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; |