[Qemu-devel] [PATCH V3 29/44] virtio-rng: add virtio-rng device.

[fred.konrad@greensocs.com]

From: KONRAD Frederic <fred.konrad@greensocs.com>

Create virtio-rng which extends virtio-device, so it can be connected on
virtio-bus.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
---
 hw/virtio-pci.c |   8 +---
 hw/virtio-rng.c | 112 +++++++++++++++++++++++++++++++++++++++++++++++++++++---
 hw/virtio-rng.h |  16 ++++++++
 3 files changed, 123 insertions(+), 13 deletions(-)

diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 6a7b41e..b6e5f9c 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -1041,13 +1041,7 @@ static void virtio_rng_initfn(Object *obj)
 
 static Property virtio_rng_properties[] = {
     DEFINE_VIRTIO_COMMON_FEATURES(VirtIOPCIProxy, host_features),
-    /* Set a default rate limit of 2^47 bytes per minute or roughly 2TB/s.  If
-       you have an entropy source capable of generating more entropy than this
-       and you can pass it through via virtio-rng, then hats off to you.  Until
-       then, this is unlimited for all practical purposes.
-    */
-    DEFINE_PROP_UINT64("max-bytes", VirtIOPCIProxy, rng.max_bytes, INT64_MAX),
-    DEFINE_PROP_UINT32("period", VirtIOPCIProxy, rng.period_ms, 1 << 16),
+    DEFINE_VIRTIO_RNG_PROPERTIES(VirtIOPCIProxy, rng),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/virtio-rng.c b/hw/virtio-rng.c
index e672c40..7332517 100644
--- a/hw/virtio-rng.c
+++ b/hw/virtio-rng.c
@@ -129,17 +129,33 @@ static void check_rate_limit(void *opaque)
                    qemu_get_clock_ms(vm_clock) + s->conf.period_ms);
 }
 
+void virtio_rng_set_conf(DeviceState *dev, VirtIORNGConf *conf)
+{
+    VirtIORNG *vrng = VIRTIO_RNG(dev);
+    memcpy(&(vrng->conf), conf, sizeof(struct VirtIORNGConf));
+}
 
-VirtIODevice *virtio_rng_init(DeviceState *dev, VirtIORNGConf *conf)
+static VirtIODevice *virtio_rng_common_init(DeviceState *dev,
+                                            VirtIORNGConf *conf,
+                                            VirtIORNG **pvrng)
 {
-    VirtIORNG *vrng;
+    VirtIORNG *vrng = *pvrng;
     VirtIODevice *vdev;
     Error *local_err = NULL;
 
-    vdev = virtio_common_init("virtio-rng", VIRTIO_ID_RNG, 0,
-                              sizeof(VirtIORNG));
-
-    vrng = DO_UPCAST(VirtIORNG, vdev, vdev);
+    /*
+     * We have two cases here: the old virtio-rng-x device, and the
+     * refactored virtio-rng.
+     * This will disappear later in the serie.
+     */
+    if (vrng == NULL) {
+        vdev = virtio_common_init("virtio-rng", VIRTIO_ID_RNG, 0,
+                                  sizeof(VirtIORNG));
+        vrng = DO_UPCAST(VirtIORNG, vdev, vdev);
+    } else {
+        vdev = VIRTIO_DEVICE(vrng);
+        virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0);
+    }
 
     vrng->rng = conf->rng;
     if (vrng->rng == NULL) {
@@ -155,6 +171,7 @@ VirtIODevice *virtio_rng_init(DeviceState *dev, VirtIORNGConf *conf)
     }
 
     vrng->vq = virtio_add_queue(vdev, 8, handle_input);
+
     vrng->vdev.get_features = get_features;
 
     vrng->qdev = dev;
@@ -175,6 +192,15 @@ VirtIODevice *virtio_rng_init(DeviceState *dev, VirtIORNGConf *conf)
     return vdev;
 }
 
+/*
+ * This two functions will be removed later in the serie.
+ */
+VirtIODevice *virtio_rng_init(DeviceState *dev, VirtIORNGConf *conf)
+{
+    VirtIORNG *vdev = NULL;
+    return virtio_rng_common_init(dev, conf, &vdev);
+}
+
 void virtio_rng_exit(VirtIODevice *vdev)
 {
     VirtIORNG *vrng = DO_UPCAST(VirtIORNG, vdev, vdev);
@@ -184,3 +210,77 @@ void virtio_rng_exit(VirtIODevice *vdev)
     unregister_savevm(vrng->qdev, "virtio-rng", vrng);
     virtio_cleanup(vdev);
 }
+
+static int virtio_rng_device_init(VirtIODevice *vdev)
+{
+    DeviceState *qdev = DEVICE(vdev);
+    VirtIORNG *vrng = VIRTIO_RNG(vdev);
+
+    if (vrng->conf.rng == NULL) {
+        vrng->conf.default_backend = RNG_RANDOM(object_new(TYPE_RNG_RANDOM));
+
+        object_property_add_child(OBJECT(qdev),
+                                  "default-backend",
+                                  OBJECT(vrng->conf.default_backend),
+                                  NULL);
+
+        object_property_set_link(OBJECT(qdev),
+                                 OBJECT(vrng->conf.default_backend),
+                                 "rng", NULL);
+    }
+
+    if (virtio_rng_common_init(qdev, &(vrng->conf), &vrng) == NULL) {
+        return -1;
+    }
+    return 0;
+}
+
+static int virtio_rng_device_exit(DeviceState *qdev)
+{
+    VirtIORNG *vrng = VIRTIO_RNG(qdev);
+    VirtIODevice *vdev = VIRTIO_DEVICE(qdev);
+
+    qemu_del_timer(vrng->rate_limit_timer);
+    qemu_free_timer(vrng->rate_limit_timer);
+    unregister_savevm(qdev, "virtio-rng", vrng);
+    virtio_common_cleanup(vdev);
+    return 0;
+}
+
+static Property virtio_rng_properties[] = {
+    DEFINE_VIRTIO_RNG_PROPERTIES(VirtIORNG, conf),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtio_rng_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+    dc->exit = virtio_rng_device_exit;
+    dc->props = virtio_rng_properties;
+    vdc->init = virtio_rng_device_init;
+    vdc->get_features = get_features;
+}
+
+static void virtio_rng_initfn(Object *obj)
+{
+    VirtIORNG *vrng = VIRTIO_RNG(obj);
+
+    object_property_add_link(obj, "rng", TYPE_RNG_BACKEND,
+                             (Object **)&vrng->conf.rng, NULL);
+}
+
+static const TypeInfo virtio_rng_info = {
+    .name = TYPE_VIRTIO_RNG,
+    .parent = TYPE_VIRTIO_DEVICE,
+    .instance_size = sizeof(VirtIORNG),
+    .instance_init = virtio_rng_initfn,
+    .class_init = virtio_rng_class_init,
+};
+
+static void virtio_register_types(void)
+{
+    type_register_static(&virtio_rng_info);
+}
+
+type_init(virtio_register_types)
diff --git a/hw/virtio-rng.h b/hw/virtio-rng.h
index 3deb283..fd6d01f 100644
--- a/hw/virtio-rng.h
+++ b/hw/virtio-rng.h
@@ -15,6 +15,10 @@
 #include "qemu/rng.h"
 #include "qemu/rng-random.h"
 
+#define TYPE_VIRTIO_RNG "virtio-rng"
+#define VIRTIO_RNG(obj) \
+        OBJECT_CHECK(VirtIORNG, (obj), TYPE_VIRTIO_RNG)
+
 /* The Virtio ID for the virtio rng device */
 #define VIRTIO_ID_RNG    4
 
@@ -44,4 +48,16 @@ typedef struct VirtIORNG {
     int64_t quota_remaining;
 } VirtIORNG;
 
+/* Set a default rate limit of 2^47 bytes per minute or roughly 2TB/s.  If
+   you have an entropy source capable of generating more entropy than this
+   and you can pass it through via virtio-rng, then hats off to you.  Until
+   then, this is unlimited for all practical purposes.
+*/
+#define DEFINE_VIRTIO_RNG_PROPERTIES(_state, _conf_field)                    \
+        DEFINE_PROP_UINT64("max-bytes", _state, _conf_field.max_bytes,       \
+                           INT64_MAX),                                       \
+        DEFINE_PROP_UINT32("period", _state, _conf_field.period_ms, 1 << 16)
+
+void virtio_rng_set_conf(DeviceState *dev, VirtIORNGConf *conf);
+
 #endif
-- 
1.7.11.7