summaryrefslogtreecommitdiff
path: root/backends/hostmem.c
blob: a2550fe7e3a5d8d976a3e437f03b34bcc9986d4a (plain)
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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 * QEMU Host Memory Backend
 *
 * Copyright (C) 2013-2014 Red Hat Inc
 *
 * Authors:
 *   Igor Mammedov <imammedo@redhat.com>
 *
 * 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 "sysemu/hostmem.h"
#include "sysemu/sysemu.h"
#include "qapi/visitor.h"
#include "qapi/qmp/qerror.h"
#include "qemu/config-file.h"
#include "qom/object_interfaces.h"

static void
host_memory_backend_get_size(Object *obj, Visitor *v, void *opaque,
                             const char *name, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);
    uint64_t value = backend->size;

    visit_type_size(v, &value, name, errp);
}

static void
host_memory_backend_set_size(Object *obj, Visitor *v, void *opaque,
                             const char *name, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);
    Error *local_err = NULL;
    uint64_t value;

    if (memory_region_size(&backend->mr)) {
        error_setg(&local_err, "cannot change property value");
        goto out;
    }

    visit_type_size(v, &value, name, &local_err);
    if (local_err) {
        goto out;
    }
    if (!value) {
        error_setg(&local_err, "Property '%s.%s' doesn't take value '%"
                   PRIu64 "'", object_get_typename(obj), name, value);
        goto out;
    }
    backend->size = value;
out:
    error_propagate(errp, local_err);
}

static bool host_memory_backend_get_merge(Object *obj, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);

    return backend->merge;
}

static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);

    if (!memory_region_size(&backend->mr)) {
        backend->merge = value;
        return;
    }

    if (value != backend->merge) {
        void *ptr = memory_region_get_ram_ptr(&backend->mr);
        uint64_t sz = memory_region_size(&backend->mr);

        qemu_madvise(ptr, sz,
                     value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE);
        backend->merge = value;
    }
}

static bool host_memory_backend_get_dump(Object *obj, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);

    return backend->dump;
}

static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);

    if (!memory_region_size(&backend->mr)) {
        backend->dump = value;
        return;
    }

    if (value != backend->dump) {
        void *ptr = memory_region_get_ram_ptr(&backend->mr);
        uint64_t sz = memory_region_size(&backend->mr);

        qemu_madvise(ptr, sz,
                     value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP);
        backend->dump = value;
    }
}

static void host_memory_backend_init(Object *obj)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);

    backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(),
                                       "mem-merge", true);
    backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(),
                                      "dump-guest-core", true);

    object_property_add_bool(obj, "merge",
                        host_memory_backend_get_merge,
                        host_memory_backend_set_merge, NULL);
    object_property_add_bool(obj, "dump",
                        host_memory_backend_get_dump,
                        host_memory_backend_set_dump, NULL);
    object_property_add(obj, "size", "int",
                        host_memory_backend_get_size,
                        host_memory_backend_set_size, NULL, NULL, NULL);
}

static void host_memory_backend_finalize(Object *obj)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(obj);

    if (memory_region_size(&backend->mr)) {
        memory_region_destroy(&backend->mr);
    }
}

MemoryRegion *
host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp)
{
    return memory_region_size(&backend->mr) ? &backend->mr : NULL;
}

static void
host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
{
    HostMemoryBackend *backend = MEMORY_BACKEND(uc);
    HostMemoryBackendClass *bc = MEMORY_BACKEND_GET_CLASS(uc);
    Error *local_err = NULL;
    void *ptr;
    uint64_t sz;

    if (bc->alloc) {
        bc->alloc(backend, &local_err);
        if (local_err) {
            error_propagate(errp, local_err);
            return;
        }

        ptr = memory_region_get_ram_ptr(&backend->mr);
        sz = memory_region_size(&backend->mr);

        if (backend->merge) {
            qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE);
        }
        if (!backend->dump) {
            qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP);
        }
    }
}

static void
host_memory_backend_class_init(ObjectClass *oc, void *data)
{
    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);

    ucc->complete = host_memory_backend_memory_complete;
}

static const TypeInfo host_memory_backend_info = {
    .name = TYPE_MEMORY_BACKEND,
    .parent = TYPE_OBJECT,
    .abstract = true,
    .class_size = sizeof(HostMemoryBackendClass),
    .class_init = host_memory_backend_class_init,
    .instance_size = sizeof(HostMemoryBackend),
    .instance_init = host_memory_backend_init,
    .instance_finalize = host_memory_backend_finalize,
    .interfaces = (InterfaceInfo[]) {
        { TYPE_USER_CREATABLE },
        { }
    }
};

static void register_types(void)
{
    type_register_static(&host_memory_backend_info);
}

type_init(register_types);