kvm tools: Add kvm__trigger_irq()

Add a helper function to trigger an IRQ.

This function is usefull when an IRQ line has to be raised and lowered
such as when using MSI-X.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

include/kvm/kvm.h

@@ -63,6 +63,7 @@ void kvm__setup_bios(struct kvm *kvm);
 void kvm__start_timer(struct kvm *kvm);
 void kvm__stop_timer(struct kvm *kvm);
 void kvm__irq_line(struct kvm *kvm, int irq, int level);
+void kvm__irq_trigger(struct kvm *kvm, int irq);
 bool kvm__emulate_io(struct kvm *kvm, u16 port, void *data, int direction, int size, u32 count);
 bool kvm__emulate_mmio(struct kvm *kvm, u64 phys_addr, u8 *data, u32 len, u8 is_write);
 void kvm__register_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr);

kvm.c

@@ -676,6 +676,12 @@ void kvm__irq_line(struct kvm *kvm, int irq, int level)
 		die_perror("KVM_IRQ_LINE failed");
 }
 
+void kvm__irq_trigger(struct kvm *kvm, int irq)
+{
+	kvm__irq_line(kvm, irq, 1);
+	kvm__irq_line(kvm, irq, 0);
+}
+
 void kvm__dump_mem(struct kvm *kvm, unsigned long addr, unsigned long size)
 {
 	unsigned char *p;