KVM: Allow PIT emulation without speaker port
The in-kernel speaker emulation is only a dummy and also unneeded from
the performance point of view. Rather, it takes user space support to
generate sound output on the host, e.g. console beeps.
To allow this, introduce KVM_CREATE_PIT2 which controls in-kernel
speaker port emulation via a flag passed along the new IOCTL. It also
leaves room for future extensions of the PIT configuration interface.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 21f68e0..0990bc9 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -563,7 +563,7 @@
}
}
-struct kvm_pit *kvm_create_pit(struct kvm *kvm)
+struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
{
struct kvm_pit *pit;
struct kvm_kpit_state *pit_state;
@@ -589,11 +589,13 @@
pit->dev.private = pit;
kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev);
- pit->speaker_dev.read = speaker_ioport_read;
- pit->speaker_dev.write = speaker_ioport_write;
- pit->speaker_dev.in_range = speaker_in_range;
- pit->speaker_dev.private = pit;
- kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev);
+ if (flags & KVM_PIT_SPEAKER_DUMMY) {
+ pit->speaker_dev.read = speaker_ioport_read;
+ pit->speaker_dev.write = speaker_ioport_write;
+ pit->speaker_dev.in_range = speaker_in_range;
+ pit->speaker_dev.private = pit;
+ kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev);
+ }
kvm->arch.vpit = pit;
pit->kvm = kvm;