Support host/guest notifiers in virtio-pci.
The last one only with kvm, that's okay
because vhost relies on kvm anyway.
Note on kvm usage: kvm ioeventfd API
is implemented on non-kvm systems as well,
this is the reason we don't need if (kvm_enabled())
around it.
Signed-off-by: Michael S. Tsirkin<address@hidden>
---
hw/virtio-pci.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 62 insertions(+), 0 deletions(-)
diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 006ff38..3f1214c 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -24,6 +24,7 @@
#include "net.h"
#include "block_int.h"
#include "loader.h"
+#include "kvm.h"
/* from Linux's linux/virtio_pci.h */
@@ -398,6 +399,65 @@ static unsigned virtio_pci_get_features(void *opaque)
return proxy->host_features;
}
+static void virtio_pci_guest_notifier_read(void *opaque)
+{
+ VirtQueue *vq = opaque;
+ EventNotifier *n = virtio_queue_guest_notifier(vq);
+ if (event_notifier_test_and_clear(n)) {
+ virtio_irq(vq);
+ }
+}
+
+static int virtio_pci_guest_notifier(void *opaque, int n, bool assign)
+{
+ VirtIOPCIProxy *proxy = opaque;
+ VirtQueue *vq = virtio_queue(proxy->vdev, n);
+ EventNotifier *notifier = virtio_queue_guest_notifier(vq);
+
+ if (assign) {
+ int r = event_notifier_init(notifier, 0);
+ if (r< 0)
+ return r;
+ qemu_set_fd_handler(event_notifier_get_fd(notifier),
+ virtio_pci_guest_notifier_read, NULL, vq);