aboutsummaryrefslogtreecommitdiff
path: root/hw/virtio/vhost-vsock-common.c
blob: 12ea87d7a7067463fe0e43b625a252f1cc4ff114 (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
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
/*
 * Parent class for vhost-vsock devices
 *
 * Copyright 2015-2020 Red Hat, Inc.
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or
 * (at your option) any later version.  See the COPYING file in the
 * top-level directory.
 */

#include "qemu/osdep.h"
#include "standard-headers/linux/virtio_vsock.h"
#include "qapi/error.h"
#include "hw/virtio/virtio-bus.h"
#include "qemu/error-report.h"
#include "hw/qdev-properties.h"
#include "hw/virtio/vhost.h"
#include "hw/virtio/vhost-vsock.h"
#include "qemu/iov.h"
#include "monitor/monitor.h"

const int feature_bits[] = {
    VIRTIO_VSOCK_F_SEQPACKET,
    VIRTIO_F_RING_RESET,
    VHOST_INVALID_FEATURE_BIT
};

uint64_t vhost_vsock_common_get_features(VirtIODevice *vdev, uint64_t features,
                                         Error **errp)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);

    if (vvc->seqpacket != ON_OFF_AUTO_OFF) {
        virtio_add_feature(&features, VIRTIO_VSOCK_F_SEQPACKET);
    }

    features = vhost_get_features(&vvc->vhost_dev, feature_bits, features);

    if (vvc->seqpacket == ON_OFF_AUTO_ON &&
        !virtio_has_feature(features, VIRTIO_VSOCK_F_SEQPACKET)) {
        error_setg(errp, "vhost-vsock backend doesn't support seqpacket");
    }

    return features;
}

int vhost_vsock_common_start(VirtIODevice *vdev)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
    int ret;
    int i;

    if (!k->set_guest_notifiers) {
        error_report("binding does not support guest notifiers");
        return -ENOSYS;
    }

    ret = vhost_dev_enable_notifiers(&vvc->vhost_dev, vdev);
    if (ret < 0) {
        error_report("Error enabling host notifiers: %d", -ret);
        return ret;
    }

    ret = k->set_guest_notifiers(qbus->parent, vvc->vhost_dev.nvqs, true);
    if (ret < 0) {
        error_report("Error binding guest notifier: %d", -ret);
        goto err_host_notifiers;
    }

    vvc->vhost_dev.acked_features = vdev->guest_features;
    ret = vhost_dev_start(&vvc->vhost_dev, vdev, true);
    if (ret < 0) {
        error_report("Error starting vhost: %d", -ret);
        goto err_guest_notifiers;
    }

    /*
     * guest_notifier_mask/pending not used yet, so just unmask
     * everything here.  virtio-pci will do the right thing by
     * enabling/disabling irqfd.
     */
    for (i = 0; i < vvc->vhost_dev.nvqs; i++) {
        vhost_virtqueue_mask(&vvc->vhost_dev, vdev, i, false);
    }

    return 0;

err_guest_notifiers:
    k->set_guest_notifiers(qbus->parent, vvc->vhost_dev.nvqs, false);
err_host_notifiers:
    vhost_dev_disable_notifiers(&vvc->vhost_dev, vdev);
    return ret;
}

void vhost_vsock_common_stop(VirtIODevice *vdev)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
    int ret;

    if (!k->set_guest_notifiers) {
        return;
    }

    vhost_dev_stop(&vvc->vhost_dev, vdev, true);

    ret = k->set_guest_notifiers(qbus->parent, vvc->vhost_dev.nvqs, false);
    if (ret < 0) {
        error_report("vhost guest notifier cleanup failed: %d", ret);
        return;
    }

    vhost_dev_disable_notifiers(&vvc->vhost_dev, vdev);
}


static void vhost_vsock_common_handle_output(VirtIODevice *vdev, VirtQueue *vq)
{
    /* Do nothing */
}

static void vhost_vsock_common_guest_notifier_mask(VirtIODevice *vdev, int idx,
                                            bool mask)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);

    /*
     * Add the check for configure interrupt, Use VIRTIO_CONFIG_IRQ_IDX -1
     * as the macro of configure interrupt's IDX, If this driver does not
     * support, the function will return
     */

    if (idx == VIRTIO_CONFIG_IRQ_IDX) {
        return;
    }
    vhost_virtqueue_mask(&vvc->vhost_dev, vdev, idx, mask);
}

static bool vhost_vsock_common_guest_notifier_pending(VirtIODevice *vdev,
                                               int idx)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);

    /*
     * Add the check for configure interrupt, Use VIRTIO_CONFIG_IRQ_IDX -1
     * as the macro of configure interrupt's IDX, If this driver does not
     * support, the function will return
     */

    if (idx == VIRTIO_CONFIG_IRQ_IDX) {
        return false;
    }
    return vhost_virtqueue_pending(&vvc->vhost_dev, idx);
}

static void vhost_vsock_common_send_transport_reset(VHostVSockCommon *vvc)
{
    VirtQueueElement *elem;
    VirtQueue *vq = vvc->event_vq;
    struct virtio_vsock_event event = {
        .id = cpu_to_le32(VIRTIO_VSOCK_EVENT_TRANSPORT_RESET),
    };

    elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
    if (!elem) {
        error_report("vhost-vsock missed transport reset event");
        return;
    }

    if (elem->out_num) {
        error_report("invalid vhost-vsock event virtqueue element with "
                     "out buffers");
        goto err;
    }

    if (iov_from_buf(elem->in_sg, elem->in_num, 0,
                     &event, sizeof(event)) != sizeof(event)) {
        error_report("vhost-vsock event virtqueue element is too short");
        goto err;
    }

    virtqueue_push(vq, elem, sizeof(event));
    virtio_notify(VIRTIO_DEVICE(vvc), vq);

    g_free(elem);
    return;

err:
    virtqueue_detach_element(vq, elem, 0);
    g_free(elem);
}

static void vhost_vsock_common_post_load_timer_cleanup(VHostVSockCommon *vvc)
{
    if (!vvc->post_load_timer) {
        return;
    }

    timer_free(vvc->post_load_timer);
    vvc->post_load_timer = NULL;
}

static void vhost_vsock_common_post_load_timer_cb(void *opaque)
{
    VHostVSockCommon *vvc = opaque;

    vhost_vsock_common_post_load_timer_cleanup(vvc);
    vhost_vsock_common_send_transport_reset(vvc);
}

int vhost_vsock_common_pre_save(void *opaque)
{
    VHostVSockCommon *vvc = opaque;

    /*
     * At this point, backend must be stopped, otherwise
     * it might keep writing to memory.
     */
    assert(!vhost_dev_is_started(&vvc->vhost_dev));

    return 0;
}

int vhost_vsock_common_post_load(void *opaque, int version_id)
{
    VHostVSockCommon *vvc = opaque;
    VirtIODevice *vdev = VIRTIO_DEVICE(vvc);

    if (virtio_queue_get_addr(vdev, 2)) {
        /*
         * Defer transport reset event to a vm clock timer so that virtqueue
         * changes happen after migration has completed.
         */
        assert(!vvc->post_load_timer);
        vvc->post_load_timer =
            timer_new_ns(QEMU_CLOCK_VIRTUAL,
                         vhost_vsock_common_post_load_timer_cb,
                         vvc);
        timer_mod(vvc->post_load_timer, 1);
    }
    return 0;
}

void vhost_vsock_common_realize(VirtIODevice *vdev)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);

    virtio_init(vdev, VIRTIO_ID_VSOCK, sizeof(struct virtio_vsock_config));

    /* Receive and transmit queues belong to vhost */
    vvc->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
                                      vhost_vsock_common_handle_output);
    vvc->trans_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
                                       vhost_vsock_common_handle_output);

    /* The event queue belongs to QEMU */
    vvc->event_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
                                       vhost_vsock_common_handle_output);

    vvc->vhost_dev.nvqs = ARRAY_SIZE(vvc->vhost_vqs);
    vvc->vhost_dev.vqs = vvc->vhost_vqs;

    vvc->post_load_timer = NULL;
}

void vhost_vsock_common_unrealize(VirtIODevice *vdev)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);

    vhost_vsock_common_post_load_timer_cleanup(vvc);

    virtio_delete_queue(vvc->recv_vq);
    virtio_delete_queue(vvc->trans_vq);
    virtio_delete_queue(vvc->event_vq);
    virtio_cleanup(vdev);
}

static struct vhost_dev *vhost_vsock_common_get_vhost(VirtIODevice *vdev)
{
    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
    return &vvc->vhost_dev;
}

static Property vhost_vsock_common_properties[] = {
    DEFINE_PROP_ON_OFF_AUTO("seqpacket", VHostVSockCommon, seqpacket,
                            ON_OFF_AUTO_AUTO),
    DEFINE_PROP_END_OF_LIST(),
};

static void vhost_vsock_common_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);
    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);

    device_class_set_props(dc, vhost_vsock_common_properties);
    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
    vdc->guest_notifier_mask = vhost_vsock_common_guest_notifier_mask;
    vdc->guest_notifier_pending = vhost_vsock_common_guest_notifier_pending;
    vdc->get_vhost = vhost_vsock_common_get_vhost;
}

static const TypeInfo vhost_vsock_common_info = {
    .name = TYPE_VHOST_VSOCK_COMMON,
    .parent = TYPE_VIRTIO_DEVICE,
    .instance_size = sizeof(VHostVSockCommon),
    .class_init = vhost_vsock_common_class_init,
    .abstract = true,
};

static void vhost_vsock_common_register_types(void)
{
    type_register_static(&vhost_vsock_common_info);
}

type_init(vhost_vsock_common_register_types)