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/include/linux/kvm.h b/include/linux/kvm.h
index 8f53f24..65df6f5 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -70,6 +70,14 @@
} chip;
};
+/* for KVM_CREATE_PIT2 */
+struct kvm_pit_config {
+ __u32 flags;
+ __u32 pad[15];
+};
+
+#define KVM_PIT_SPEAKER_DUMMY 1
+
#define KVM_EXIT_UNKNOWN 0
#define KVM_EXIT_EXCEPTION 1
#define KVM_EXIT_IO 2
@@ -419,6 +427,9 @@
#define KVM_CAP_MCE 31
#endif
#define KVM_CAP_IRQFD 32
+#ifdef __KVM_HAVE_PIT
+#define KVM_CAP_PIT2 33
+#endif
#ifdef KVM_CAP_IRQ_ROUTING
@@ -525,6 +536,7 @@
_IOW(KVMIO, 0x74, struct kvm_assigned_msix_entry)
#define KVM_DEASSIGN_DEV_IRQ _IOW(KVMIO, 0x75, struct kvm_assigned_irq)
#define KVM_IRQFD _IOW(KVMIO, 0x76, struct kvm_irqfd)
+#define KVM_CREATE_PIT2 _IOW(KVMIO, 0x77, struct kvm_pit_config)
/*
* ioctls for vcpu fds