xref: /openbmc/qemu/include/hw/virtio/virtio-rng.h (revision 0bc12c4f)
1 /*
2  * Virtio RNG Support
3  *
4  * Copyright Red Hat, Inc. 2012
5  * Copyright Amit Shah <amit.shah@redhat.com>
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2 or
8  * (at your option) any later version.  See the COPYING file in the
9  * top-level directory.
10  */
11 
12 #ifndef _QEMU_VIRTIO_RNG_H
13 #define _QEMU_VIRTIO_RNG_H
14 
15 #include "sysemu/rng.h"
16 #include "sysemu/rng-random.h"
17 #include "standard-headers/linux/virtio_rng.h"
18 
19 #define TYPE_VIRTIO_RNG "virtio-rng-device"
20 #define VIRTIO_RNG(obj) \
21         OBJECT_CHECK(VirtIORNG, (obj), TYPE_VIRTIO_RNG)
22 #define VIRTIO_RNG_GET_PARENT_CLASS(obj) \
23         OBJECT_GET_PARENT_CLASS(obj, TYPE_VIRTIO_RNG)
24 
25 struct VirtIORNGConf {
26     RngBackend *rng;
27     uint64_t max_bytes;
28     uint32_t period_ms;
29     RndRandom *default_backend;
30 };
31 
32 typedef struct VirtIORNG {
33     VirtIODevice parent_obj;
34 
35     /* Only one vq - guest puts buffer(s) on it when it needs entropy */
36     VirtQueue *vq;
37 
38     VirtIORNGConf conf;
39 
40     RngBackend *rng;
41 
42     /* We purposefully don't migrate this state.  The quota will reset on the
43      * destination as a result.  Rate limiting is host state, not guest state.
44      */
45     QEMUTimer *rate_limit_timer;
46     int64_t quota_remaining;
47 } VirtIORNG;
48 
49 #endif
50