1 files changed, 62 insertions, 0 deletions
diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h
new file mode 100644
index 0000000000..9380cb5413
--- /dev/null
+++ b/include/hw/virtio/dataplane/vring.h
@@ -0,0 +1,62 @@
+/* Copyright 2012 Red Hat, Inc. and/or its affiliates
+ * Copyright IBM, Corp. 2012
+ *
+ * Based on Linux 2.6.39 vhost code:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Copyright (C) 2006 Rusty Russell IBM Corporation
+ *
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ *         Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * Inspiration, some code, and most witty comments come from
+ * Documentation/virtual/lguest/lguest.c, by Rusty Russell
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+
+#ifndef VRING_H
+#define VRING_H
+
+#include <linux/virtio_ring.h>
+#include "qemu-common.h"
+#include "hostmem.h"
+#include "hw/virtio/virtio.h"
+
+typedef struct {
+    HostMem hostmem;                /* guest memory mapper */
+    struct vring vr;                /* virtqueue vring mapped to host memory */
+    uint16_t last_avail_idx;        /* last processed avail ring index */
+    uint16_t last_used_idx;         /* last processed used ring index */
+    uint16_t signalled_used;        /* EVENT_IDX state */
+    bool signalled_used_valid;
+    bool broken;                    /* was there a fatal error? */
+} Vring;
+
+static inline unsigned int vring_get_num(Vring *vring)
+{
+    return vring->vr.num;
+}
+
+/* Are there more descriptors available? */
+static inline bool vring_more_avail(Vring *vring)
+{
+    return vring->vr.avail->idx != vring->last_avail_idx;
+}
+
+/* Fail future vring_pop() and vring_push() calls until reset */
+static inline void vring_set_broken(Vring *vring)
+{
+    vring->broken = true;
+}
+
+bool vring_setup(Vring *vring, VirtIODevice *vdev, int n);
+void vring_teardown(Vring *vring);
+void vring_disable_notification(VirtIODevice *vdev, Vring *vring);
+bool vring_enable_notification(VirtIODevice *vdev, Vring *vring);
+bool vring_should_notify(VirtIODevice *vdev, Vring *vring);
+int vring_pop(VirtIODevice *vdev, Vring *vring,
+              struct iovec iov[], struct iovec *iov_end,
+              unsigned int *out_num, unsigned int *in_num);
+void vring_push(Vring *vring, unsigned int head, int len);
+
+#endif /* VRING_H */