[PATCH 2/4] KVM: Add kvm_inject_realmode_interrupt() wrapper

Avi Kivity
2010-09-19T12:34:11Z

From: Mohammed Gamal <m.gamal005@gmail.com>

This adds a wrapper function kvm_inject_realmode_interrupt() around the
emulator function emulate_int_real() to allow real mode interrupt injection.

[avi: initialize operand and address sizes before emulating interrupts]
[avi: initialize rip for real mode interrupt injection]
[avi: clear interrupt pending flag after emulating interrupt injection]

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/x86/kvm/x86.c | 29 +++++++++++++++++++++++++++++
arch/x86/kvm/x86.h | 1 +
2 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a51635e..a3fc151 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4187,6 +4187,35 @@ static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
}

+int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq)
+{
+ struct decode_cache *c = &vcpu->arch.emulate_ctxt.decode;
+ int ret;
+
+ init_emulate_ctxt(vcpu);
+
+ vcpu->arch.emulate_ctxt.decode.op_bytes = 2;
+ vcpu->arch.emulate_ctxt.decode.ad_bytes = 2;
+ vcpu->arch.emulate_ctxt.decode.eip = vcpu->arch.emulate_ctxt.eip;
+ ret = emulate_int_real(&vcpu->arch.emulate_ctxt, &emulate_ops, irq);
+
+ if (ret != X86EMUL_CONTINUE)
+ return EMULATE_FAIL;
+
+ vcpu->arch.emulate_ctxt.eip = c->eip;
+ memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
+ kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
+ kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+
+ if (irq == NMI_VECTOR)
+ vcpu->arch.nmi_pending = false;
+ else
+ vcpu->arch.interrupt.pending = false;
+
+ return EMULATE_DONE;
+}
+EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);
+
static int handle_emulation_failure(struct kvm_vcpu *vcpu)
{
++vcpu->stat.insn_emulation_fail;
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index bf4dc2f..2cea414 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -72,6 +72,7 @@ static inline int is_paging(struct kvm_vcpu *vcpu)

void kvm_before_handle_nmi(struct kvm_vcpu *vcpu);
void kvm_after_handle_nmi(struct kvm_vcpu *vcpu);
+int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq);

void kvm_write_tsc(struct kvm_vcpu *vcpu, u64 data);

--
1.7.2.3