1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/*
* QEMU sPAPR random number generator "device" for H_RANDOM hypercall
*
* Copyright 2015 Thomas Huth, Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "cpu.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"
#include "sysemu/sysemu.h"
#include "sysemu/device_tree.h"
#include "sysemu/rng.h"
#include "hw/ppc/spapr.h"
#include "hw/qdev-properties.h"
#include "kvm_ppc.h"
#define SPAPR_RNG(obj) \
OBJECT_CHECK(SpaprRngState, (obj), TYPE_SPAPR_RNG)
struct SpaprRngState {
/*< private >*/
DeviceState ds;
RngBackend *backend;
bool use_kvm;
};
typedef struct SpaprRngState SpaprRngState;
struct HRandomData {
QemuSemaphore sem;
union {
uint64_t v64;
uint8_t v8[8];
} val;
int received;
};
typedef struct HRandomData HRandomData;
/* Callback function for the RngBackend */
static void random_recv(void *dest, const void *src, size_t size)
{
HRandomData *hrdp = dest;
if (src && size > 0) {
assert(size + hrdp->received <= sizeof(hrdp->val.v8));
memcpy(&hrdp->val.v8[hrdp->received], src, size);
hrdp->received += size;
}
qemu_sem_post(&hrdp->sem);
}
/* Handler for the H_RANDOM hypercall */
static target_ulong h_random(PowerPCCPU *cpu, SpaprMachineState *spapr,
target_ulong opcode, target_ulong *args)
{
SpaprRngState *rngstate;
HRandomData hrdata;
rngstate = SPAPR_RNG(object_resolve_path_type("", TYPE_SPAPR_RNG, NULL));
if (!rngstate || !rngstate->backend) {
return H_HARDWARE;
}
qemu_sem_init(&hrdata.sem, 0);
hrdata.val.v64 = 0;
hrdata.received = 0;
while (hrdata.received < 8) {
rng_backend_request_entropy(rngstate->backend, 8 - hrdata.received,
random_recv, &hrdata);
qemu_mutex_unlock_iothread();
qemu_sem_wait(&hrdata.sem);
qemu_mutex_lock_iothread();
}
qemu_sem_destroy(&hrdata.sem);
args[0] = hrdata.val.v64;
return H_SUCCESS;
}
static void spapr_rng_instance_init(Object *obj)
{
if (object_resolve_path_type("", TYPE_SPAPR_RNG, NULL) != NULL) {
error_report("spapr-rng can not be instantiated twice!");
return;
}
object_property_set_description(obj, "rng",
"ID of the random number generator backend",
NULL);
}
static void spapr_rng_realize(DeviceState *dev, Error **errp)
{
SpaprRngState *rngstate = SPAPR_RNG(dev);
if (rngstate->use_kvm) {
if (kvmppc_enable_hwrng() == 0) {
return;
}
/*
* If user specified both, use-kvm and a backend, we fall back to
* the backend now. If not, provide an appropriate error message.
*/
if (!rngstate->backend) {
error_setg(errp, "Could not initialize in-kernel H_RANDOM call!");
return;
}
}
if (rngstate->backend) {
spapr_register_hypercall(H_RANDOM, h_random);
} else {
error_setg(errp, "spapr-rng needs an RNG backend!");
}
}
static Property spapr_rng_properties[] = {
DEFINE_PROP_BOOL("use-kvm", SpaprRngState, use_kvm, false),
DEFINE_PROP_LINK("rng", SpaprRngState, backend, TYPE_RNG_BACKEND,
RngBackend *),
DEFINE_PROP_END_OF_LIST(),
};
static void spapr_rng_class_init(ObjectClass *oc, void *data)
{
DeviceClass *dc = DEVICE_CLASS(oc);
dc->realize = spapr_rng_realize;
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
dc->props = spapr_rng_properties;
dc->hotpluggable = false;
}
static const TypeInfo spapr_rng_info = {
.name = TYPE_SPAPR_RNG,
.parent = TYPE_DEVICE,
.instance_size = sizeof(SpaprRngState),
.instance_init = spapr_rng_instance_init,
.class_init = spapr_rng_class_init,
};
static void spapr_rng_register_type(void)
{
type_register_static(&spapr_rng_info);
}
type_init(spapr_rng_register_type)
|
