KVM: Introduce direct MSI message injection for in-kernel irqchips
Currently, MSI messages can only be injected to in-kernel irqchips by
defining a corresponding IRQ route for each message. This is not only
unhandy if the MSI messages are generated "on the fly" by user space,
IRQ routes are a limited resource that user space has to manage
carefully.
By providing a direct injection path, we can both avoid using up limited
resources and simplify the necessary steps for user land.
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 7a9dd4b..225b452 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -590,6 +590,7 @@
#define KVM_CAP_SYNC_REGS 74
#define KVM_CAP_PCI_2_3 75
#define KVM_CAP_KVMCLOCK_CTRL 76
+#define KVM_CAP_SIGNAL_MSI 77
#ifdef KVM_CAP_IRQ_ROUTING
@@ -715,6 +716,14 @@
__u64 addr;
};
+struct kvm_msi {
+ __u32 address_lo;
+ __u32 address_hi;
+ __u32 data;
+ __u32 flags;
+ __u8 pad[16];
+};
+
/*
* ioctls for VM fds
*/
@@ -789,6 +798,8 @@
/* Available with KVM_CAP_PCI_2_3 */
#define KVM_ASSIGN_SET_INTX_MASK _IOW(KVMIO, 0xa4, \
struct kvm_assigned_pci_dev)
+/* Available with KVM_CAP_SIGNAL_MSI */
+#define KVM_SIGNAL_MSI _IOW(KVMIO, 0xa5, struct kvm_msi)
/*
* ioctls for vcpu fds