Merge tag 'pull-testing-gdbstub-plugins-gitdm-061022-3' of https://github.com/stsquad...
[qemu.git] / hw / virtio / vhost-user-i2c.c
1 /*
2 * Vhost-user i2c virtio device
3 *
4 * Copyright (c) 2021 Viresh Kumar <viresh.kumar@linaro.org>
5 *
6 * SPDX-License-Identifier: GPL-2.0-or-later
7 */
8
9 #include "qemu/osdep.h"
10 #include "qapi/error.h"
11 #include "hw/qdev-properties.h"
12 #include "hw/virtio/virtio-bus.h"
13 #include "hw/virtio/vhost-user-i2c.h"
14 #include "qemu/error-report.h"
15 #include "standard-headers/linux/virtio_ids.h"
16
17 /* Remove this once the header is updated in Linux kernel */
18 #ifndef VIRTIO_ID_I2C_ADAPTER
19 #define VIRTIO_ID_I2C_ADAPTER 34
20 #endif
21
22 static void vu_i2c_start(VirtIODevice *vdev)
23 {
24 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
25 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
26 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
27 int ret, i;
28
29 if (!k->set_guest_notifiers) {
30 error_report("binding does not support guest notifiers");
31 return;
32 }
33
34 ret = vhost_dev_enable_notifiers(&i2c->vhost_dev, vdev);
35 if (ret < 0) {
36 error_report("Error enabling host notifiers: %d", -ret);
37 return;
38 }
39
40 ret = k->set_guest_notifiers(qbus->parent, i2c->vhost_dev.nvqs, true);
41 if (ret < 0) {
42 error_report("Error binding guest notifier: %d", -ret);
43 goto err_host_notifiers;
44 }
45
46 i2c->vhost_dev.acked_features = vdev->guest_features;
47
48 ret = vhost_dev_start(&i2c->vhost_dev, vdev);
49 if (ret < 0) {
50 error_report("Error starting vhost-user-i2c: %d", -ret);
51 goto err_guest_notifiers;
52 }
53
54 /*
55 * guest_notifier_mask/pending not used yet, so just unmask
56 * everything here. virtio-pci will do the right thing by
57 * enabling/disabling irqfd.
58 */
59 for (i = 0; i < i2c->vhost_dev.nvqs; i++) {
60 vhost_virtqueue_mask(&i2c->vhost_dev, vdev, i, false);
61 }
62
63 return;
64
65 err_guest_notifiers:
66 k->set_guest_notifiers(qbus->parent, i2c->vhost_dev.nvqs, false);
67 err_host_notifiers:
68 vhost_dev_disable_notifiers(&i2c->vhost_dev, vdev);
69 }
70
71 static void vu_i2c_stop(VirtIODevice *vdev)
72 {
73 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
74 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
75 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
76 int ret;
77
78 if (!k->set_guest_notifiers) {
79 return;
80 }
81
82 vhost_dev_stop(&i2c->vhost_dev, vdev);
83
84 ret = k->set_guest_notifiers(qbus->parent, i2c->vhost_dev.nvqs, false);
85 if (ret < 0) {
86 error_report("vhost guest notifier cleanup failed: %d", ret);
87 return;
88 }
89
90 vhost_dev_disable_notifiers(&i2c->vhost_dev, vdev);
91 }
92
93 static void vu_i2c_set_status(VirtIODevice *vdev, uint8_t status)
94 {
95 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
96 bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
97
98 if (!vdev->vm_running) {
99 should_start = false;
100 }
101
102 if (i2c->vhost_dev.started == should_start) {
103 return;
104 }
105
106 if (should_start) {
107 vu_i2c_start(vdev);
108 } else {
109 vu_i2c_stop(vdev);
110 }
111 }
112
113 static uint64_t vu_i2c_get_features(VirtIODevice *vdev,
114 uint64_t requested_features, Error **errp)
115 {
116 /* No feature bits used yet */
117 return requested_features;
118 }
119
120 static void vu_i2c_handle_output(VirtIODevice *vdev, VirtQueue *vq)
121 {
122 /*
123 * Not normally called; it's the daemon that handles the queue;
124 * however virtio's cleanup path can call this.
125 */
126 }
127
128 static void vu_i2c_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
129 {
130 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
131
132 vhost_virtqueue_mask(&i2c->vhost_dev, vdev, idx, mask);
133 }
134
135 static bool vu_i2c_guest_notifier_pending(VirtIODevice *vdev, int idx)
136 {
137 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
138
139 return vhost_virtqueue_pending(&i2c->vhost_dev, idx);
140 }
141
142 static void do_vhost_user_cleanup(VirtIODevice *vdev, VHostUserI2C *i2c)
143 {
144 vhost_user_cleanup(&i2c->vhost_user);
145 virtio_delete_queue(i2c->vq);
146 virtio_cleanup(vdev);
147 g_free(i2c->vhost_dev.vqs);
148 i2c->vhost_dev.vqs = NULL;
149 }
150
151 static int vu_i2c_connect(DeviceState *dev)
152 {
153 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
154 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
155
156 if (i2c->connected) {
157 return 0;
158 }
159 i2c->connected = true;
160
161 /* restore vhost state */
162 if (virtio_device_started(vdev, vdev->status)) {
163 vu_i2c_start(vdev);
164 }
165
166 return 0;
167 }
168
169 static void vu_i2c_disconnect(DeviceState *dev)
170 {
171 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
172 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
173
174 if (!i2c->connected) {
175 return;
176 }
177 i2c->connected = false;
178
179 if (i2c->vhost_dev.started) {
180 vu_i2c_stop(vdev);
181 }
182 }
183
184 static void vu_i2c_event(void *opaque, QEMUChrEvent event)
185 {
186 DeviceState *dev = opaque;
187 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
188 VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
189
190 switch (event) {
191 case CHR_EVENT_OPENED:
192 if (vu_i2c_connect(dev) < 0) {
193 qemu_chr_fe_disconnect(&i2c->chardev);
194 return;
195 }
196 break;
197 case CHR_EVENT_CLOSED:
198 vu_i2c_disconnect(dev);
199 break;
200 case CHR_EVENT_BREAK:
201 case CHR_EVENT_MUX_IN:
202 case CHR_EVENT_MUX_OUT:
203 /* Ignore */
204 break;
205 }
206 }
207
208 static void vu_i2c_device_realize(DeviceState *dev, Error **errp)
209 {
210 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
211 VHostUserI2C *i2c = VHOST_USER_I2C(dev);
212 int ret;
213
214 if (!i2c->chardev.chr) {
215 error_setg(errp, "vhost-user-i2c: missing chardev");
216 return;
217 }
218
219 if (!vhost_user_init(&i2c->vhost_user, &i2c->chardev, errp)) {
220 return;
221 }
222
223 virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0);
224
225 i2c->vhost_dev.nvqs = 1;
226 i2c->vq = virtio_add_queue(vdev, 4, vu_i2c_handle_output);
227 i2c->vhost_dev.vqs = g_new0(struct vhost_virtqueue, i2c->vhost_dev.nvqs);
228
229 ret = vhost_dev_init(&i2c->vhost_dev, &i2c->vhost_user,
230 VHOST_BACKEND_TYPE_USER, 0, errp);
231 if (ret < 0) {
232 do_vhost_user_cleanup(vdev, i2c);
233 }
234
235 qemu_chr_fe_set_handlers(&i2c->chardev, NULL, NULL, vu_i2c_event, NULL,
236 dev, NULL, true);
237 }
238
239 static void vu_i2c_device_unrealize(DeviceState *dev)
240 {
241 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
242 VHostUserI2C *i2c = VHOST_USER_I2C(dev);
243
244 /* This will stop vhost backend if appropriate. */
245 vu_i2c_set_status(vdev, 0);
246 vhost_dev_cleanup(&i2c->vhost_dev);
247 do_vhost_user_cleanup(vdev, i2c);
248 }
249
250 static const VMStateDescription vu_i2c_vmstate = {
251 .name = "vhost-user-i2c",
252 .unmigratable = 1,
253 };
254
255 static Property vu_i2c_properties[] = {
256 DEFINE_PROP_CHR("chardev", VHostUserI2C, chardev),
257 DEFINE_PROP_END_OF_LIST(),
258 };
259
260 static void vu_i2c_class_init(ObjectClass *klass, void *data)
261 {
262 DeviceClass *dc = DEVICE_CLASS(klass);
263 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
264
265 device_class_set_props(dc, vu_i2c_properties);
266 dc->vmsd = &vu_i2c_vmstate;
267 set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
268 vdc->realize = vu_i2c_device_realize;
269 vdc->unrealize = vu_i2c_device_unrealize;
270 vdc->get_features = vu_i2c_get_features;
271 vdc->set_status = vu_i2c_set_status;
272 vdc->guest_notifier_mask = vu_i2c_guest_notifier_mask;
273 vdc->guest_notifier_pending = vu_i2c_guest_notifier_pending;
274 }
275
276 static const TypeInfo vu_i2c_info = {
277 .name = TYPE_VHOST_USER_I2C,
278 .parent = TYPE_VIRTIO_DEVICE,
279 .instance_size = sizeof(VHostUserI2C),
280 .class_init = vu_i2c_class_init,
281 };
282
283 static void vu_i2c_register_types(void)
284 {
285 type_register_static(&vu_i2c_info);
286 }
287
288 type_init(vu_i2c_register_types)