From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: fwilhelm@google.com, seanjc@google.com, oupton@google.com,
stable@vger.kernel.org
Subject: [PATCH 5/8] KVM: x86: split the two parts of emulator_pio_in
Date: Wed, 13 Oct 2021 12:56:13 -0400 [thread overview]
Message-ID: <20211013165616.19846-6-pbonzini@redhat.com> (raw)
In-Reply-To: <20211013165616.19846-1-pbonzini@redhat.com>
emulator_pio_in handles both the case where the data is pending in
vcpu->arch.pio.count, and the case where I/O has to be done via either
an in-kernel device or a userspace exit. For SEV-ES we would like
to split these, to identify clearly the moment at which the
sev_pio_data is consumed. To this end, create two different
functions: __emulator_pio_in fills in vcpu->arch.pio.count, while
complete_emulator_pio_in clears it and releases vcpu->arch.pio.data.
While at it, remove the void* argument also from emulator_pio_in_out.
No functional change intended.
Cc: stable@vger.kernel.org
Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/x86.c | 42 +++++++++++++++++++++++-------------------
1 file changed, 23 insertions(+), 19 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8880dc36a2b4..07d9533b471d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6906,7 +6906,7 @@ static int kernel_pio(struct kvm_vcpu *vcpu, void *pd)
}
static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size,
- unsigned short port, void *val,
+ unsigned short port,
unsigned int count, bool in)
{
vcpu->arch.pio.port = port;
@@ -6927,26 +6927,31 @@ static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size,
return 0;
}
-static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
- unsigned short port, void *val, unsigned int count)
+static int __emulator_pio_in(struct kvm_vcpu *vcpu, int size,
+ unsigned short port, unsigned int count)
{
- int ret;
-
- if (vcpu->arch.pio.count)
- goto data_avail;
-
+ WARN_ON(vcpu->arch.pio.count);
memset(vcpu->arch.pio_data, 0, size * count);
+ return emulator_pio_in_out(vcpu, size, port, count, true);
+}
- ret = emulator_pio_in_out(vcpu, size, port, val, count, true);
- if (ret) {
-data_avail:
- memcpy(val, vcpu->arch.pio_data, size * count);
- trace_kvm_pio(KVM_PIO_IN, port, size, count, vcpu->arch.pio_data);
- vcpu->arch.pio.count = 0;
- return 1;
- }
+static void complete_emulator_pio_in(struct kvm_vcpu *vcpu, int size,
+ unsigned short port, void *val)
+{
+ memcpy(val, vcpu->arch.pio_data, size * vcpu->arch.pio.count);
+ trace_kvm_pio(KVM_PIO_IN, port, size, vcpu->arch.pio.count, vcpu->arch.pio_data);
+ vcpu->arch.pio.count = 0;
+}
- return 0;
+static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
+ unsigned short port, void *val, unsigned int count)
+{
+ if (!vcpu->arch.pio.count && !__emulator_pio_in(vcpu, size, port, count))
+ return 0;
+
+ WARN_ON(count != vcpu->arch.pio.count);
+ complete_emulator_pio_in(vcpu, size, port, val);
+ return 1;
}
static int emulator_pio_in_emulated(struct x86_emulate_ctxt *ctxt,
@@ -6965,12 +6970,11 @@ static int emulator_pio_out(struct kvm_vcpu *vcpu, int size,
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, (void *)val, count, false);
+ ret = emulator_pio_in_out(vcpu, size, port, count, false);
if (ret)
vcpu->arch.pio.count = 0;
return ret;
-
}
static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt,
--
2.27.0
next prev parent reply other threads:[~2021-10-13 16:57 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-13 16:56 [PATCH 0/8] KVM: SEV-ES: fixes for string I/O emulation Paolo Bonzini
2021-10-13 16:56 ` [PATCH 1/8] KVM: SEV-ES: fix length of string I/O Paolo Bonzini
2021-10-14 20:13 ` Tom Lendacky
2021-10-21 23:10 ` Maxim Levitsky
2021-10-25 1:31 ` Marc Orr
2021-10-25 8:59 ` Paolo Bonzini
2021-10-13 16:56 ` [PATCH 2/8] KVM: SEV-ES: rename guest_ins_data to sev_pio_data Paolo Bonzini
2021-10-21 23:12 ` Maxim Levitsky
2021-10-13 16:56 ` [PATCH 3/8] KVM: x86: leave vcpu->arch.pio.count alone in emulator_pio_in_out Paolo Bonzini
2021-10-21 23:12 ` Maxim Levitsky
2021-10-13 16:56 ` [PATCH 4/8] KVM: SEV-ES: clean up kvm_sev_es_ins/outs Paolo Bonzini
2021-10-21 23:14 ` Maxim Levitsky
2021-10-22 16:31 ` Paolo Bonzini
2021-10-13 16:56 ` Paolo Bonzini [this message]
2021-10-21 23:14 ` [PATCH 5/8] KVM: x86: split the two parts of emulator_pio_in Maxim Levitsky
2021-10-13 16:56 ` [PATCH 6/8] KVM: x86: remove unnecessary arguments from complete_emulator_pio_in Paolo Bonzini
2021-10-21 23:14 ` Maxim Levitsky
2021-10-13 16:56 ` [PATCH 7/8] KVM: SEV-ES: keep INS functions together Paolo Bonzini
2021-10-21 23:14 ` Maxim Levitsky
2021-10-13 16:56 ` [PATCH 8/8] KVM: SEV-ES: go over the sev_pio_data buffer in multiple passes if needed Paolo Bonzini
2021-10-21 23:15 ` Maxim Levitsky
2021-10-21 17:47 ` [PATCH 0/8] KVM: SEV-ES: fixes for string I/O emulation Paolo Bonzini
2021-10-21 20:04 ` Sean Christopherson
2021-10-21 23:49 ` Sean Christopherson
2021-10-22 13:33 ` Paolo Bonzini
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