tests: Add virtio device initialization

Add functions to read and write virtio header fields.
Add status bit setting in virtio-blk-device.

Signed-off-by: Marc Marí <marc.mari.barcelo@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

tests/libqos/virtio.c

@@ -0,0 +1,55 @@
+/*
+ * libqos virtio driver
+ *
+ * Copyright (c) 2014 Marc Marí
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <glib.h>
+#include "libqtest.h"
+#include "libqos/virtio.h"
+
+uint8_t qvirtio_config_readb(const QVirtioBus *bus, QVirtioDevice *d,
+                                                                void *addr)
+{
+    return bus->config_readb(d, addr);
+}
+
+uint16_t qvirtio_config_readw(const QVirtioBus *bus, QVirtioDevice *d,
+                                                                void *addr)
+{
+    return bus->config_readw(d, addr);
+}
+
+uint32_t qvirtio_config_readl(const QVirtioBus *bus, QVirtioDevice *d,
+                                                                void *addr)
+{
+    return bus->config_readl(d, addr);
+}
+
+uint64_t qvirtio_config_readq(const QVirtioBus *bus, QVirtioDevice *d,
+                                                                void *addr)
+{
+    return bus->config_readq(d, addr);
+}
+
+void qvirtio_reset(const QVirtioBus *bus, QVirtioDevice *d)
+{
+    bus->set_status(d, QVIRTIO_RESET);
+    g_assert_cmphex(bus->get_status(d), ==, QVIRTIO_RESET);
+}
+
+void qvirtio_set_acknowledge(const QVirtioBus *bus, QVirtioDevice *d)
+{
+    bus->set_status(d, bus->get_status(d) | QVIRTIO_ACKNOWLEDGE);
+    g_assert_cmphex(bus->get_status(d), ==, QVIRTIO_ACKNOWLEDGE);
+}
+
+void qvirtio_set_driver(const QVirtioBus *bus, QVirtioDevice *d)
+{
+    bus->set_status(d, bus->get_status(d) | QVIRTIO_DRIVER);
+    g_assert_cmphex(bus->get_status(d), ==,
+                                    QVIRTIO_DRIVER | QVIRTIO_ACKNOWLEDGE);
+}