Add a new flag in ioeventfd ioctl to support asyncio. After that, the IO
request will be processed in asyncio path by kernel and hypervisor.

Signed-off-by: Conghui <conghui.chen@...>
---
devicemodel/hw/pci/virtio/virtio.c | 6 +++++-
devicemodel/include/public/hsm_ioctl_defs.h | 1 +
2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/devicemodel/hw/pci/virtio/virtio.c b/devicemodel/hw/pci/virtio/virtio.c
index 546ec6f31..598bdbc5f 100644
--- a/devicemodel/hw/pci/virtio/virtio.c
+++ b/devicemodel/hw/pci/virtio/virtio.c
@@ -2000,7 +2000,11 @@ int virtio_register_ioeventfd(struct virtio_base *base, int idx, bool is_registe

if (!is_register)
ioeventfd.flags = ACRN_IOEVENTFD_FLAG_DEASSIGN;
-
+ else
+ /* Enable ASYNCIO by default. If ASYNCIO is not supported by kernel
+ * or hyperviosr, this flag will be ignored.
+ */
+ ioeventfd.flags = ACRN_IOEVENTFD_FLAG_ASYNCIO;
/* register ioeventfd for kick */
if (base->device_caps & (1UL << VIRTIO_F_VERSION_1)) {
/*
diff --git a/devicemodel/include/public/hsm_ioctl_defs.h b/devicemodel/include/public/hsm_ioctl_defs.h
index 56b3b7ed7..be99b5bf7 100644
--- a/devicemodel/include/public/hsm_ioctl_defs.h
+++ b/devicemodel/include/public/hsm_ioctl_defs.h
@@ -226,6 +226,7 @@ struct acrn_ioeventfd {
#define ACRN_IOEVENTFD_FLAG_PIO 0x01
#define ACRN_IOEVENTFD_FLAG_DATAMATCH 0x02
#define ACRN_IOEVENTFD_FLAG_DEASSIGN 0x04
+#define ACRN_IOEVENTFD_FLAG_ASYNCIO 0x08
/** file descriptor of the eventfd of this ioeventfd */
int32_t fd;
/** flag for ioeventfd ioctl */
--
2.25.1