[mirror_qemu.git] / hw / virtio / vhost-user-gpio.c

/*
 * Vhost-user GPIO virtio device
 *
 * Copyright (c) 2022 Viresh Kumar <viresh.kumar@linaro.org>
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "qemu/osdep.h"
#include "qapi/error.h"
#include "hw/qdev-properties.h"
#include "hw/virtio/virtio-bus.h"
#include "hw/virtio/vhost-user-gpio.h"
#include "qemu/error-report.h"
#include "standard-headers/linux/virtio_ids.h"
#include "trace.h"

#define REALIZE_CONNECTION_RETRIES 3

/* Features required from VirtIO */
static const int feature_bits[] = {
    VIRTIO_F_VERSION_1,
    VIRTIO_F_NOTIFY_ON_EMPTY,
    VIRTIO_RING_F_INDIRECT_DESC,
    VIRTIO_RING_F_EVENT_IDX,
    VIRTIO_GPIO_F_IRQ,
    VIRTIO_F_RING_RESET,
    VHOST_INVALID_FEATURE_BIT
};

static void vu_gpio_get_config(VirtIODevice *vdev, uint8_t *config)
{
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);

    memcpy(config, &gpio->config, sizeof(gpio->config));
}

static int vu_gpio_config_notifier(struct vhost_dev *dev)
{
    VHostUserGPIO *gpio = VHOST_USER_GPIO(dev->vdev);

    memcpy(dev->vdev->config, &gpio->config, sizeof(gpio->config));
    virtio_notify_config(dev->vdev);

    return 0;
}

const VhostDevConfigOps gpio_ops = {
    .vhost_dev_config_notifier = vu_gpio_config_notifier,
};

static int vu_gpio_start(VirtIODevice *vdev)
{
    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
    struct vhost_dev *vhost_dev = &gpio->vhost_dev;
    int ret, i;

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

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

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

    /*
     * Before we start up we need to ensure we have the final feature
     * set needed for the vhost configuration. The backend may also
     * apply backend_features when the feature set is sent.
     */
    vhost_ack_features(&gpio->vhost_dev, feature_bits, vdev->guest_features);

    ret = vhost_dev_start(&gpio->vhost_dev, vdev, false);
    if (ret < 0) {
        error_report("Error starting vhost-user-gpio: %d", ret);
        goto err_guest_notifiers;
    }
    gpio->started_vu = true;

    /*
     * 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 < gpio->vhost_dev.nvqs; i++) {
        vhost_virtqueue_mask(&gpio->vhost_dev, vdev, i, false);
    }

    /*
     * As we must have VHOST_USER_F_PROTOCOL_FEATURES (because
     * VHOST_USER_GET_CONFIG requires it) we need to explicitly enable
     * the vrings.
     */
    g_assert(vhost_dev->vhost_ops &&
             vhost_dev->vhost_ops->vhost_set_vring_enable);
    ret = vhost_dev->vhost_ops->vhost_set_vring_enable(vhost_dev, true);
    if (ret == 0) {
        return 0;
    }

    error_report("Failed to start vrings for vhost-user-gpio: %d", ret);

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

    return ret;
}

static void vu_gpio_stop(VirtIODevice *vdev)
{
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
    struct vhost_dev *vhost_dev = &gpio->vhost_dev;
    int ret;

    if (!gpio->started_vu) {
        return;
    }
    gpio->started_vu = false;

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

    vhost_dev_stop(vhost_dev, vdev, false);

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

    vhost_dev_disable_notifiers(vhost_dev, vdev);
}

static void vu_gpio_set_status(VirtIODevice *vdev, uint8_t status)
{
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
    bool should_start = virtio_device_should_start(vdev, status);

    trace_virtio_gpio_set_status(status);

    if (!gpio->connected) {
        return;
    }

    if (vhost_dev_is_started(&gpio->vhost_dev) == should_start) {
        return;
    }

    if (should_start) {
        if (vu_gpio_start(vdev)) {
            qemu_chr_fe_disconnect(&gpio->chardev);
        }
    } else {
        vu_gpio_stop(vdev);
    }
}

static uint64_t vu_gpio_get_features(VirtIODevice *vdev, uint64_t features,
                                     Error **errp)
{
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);

    return vhost_get_features(&gpio->vhost_dev, feature_bits, features);
}

static void vu_gpio_handle_output(VirtIODevice *vdev, VirtQueue *vq)
{
    /*
     * Not normally called; it's the daemon that handles the queue;
     * however virtio's cleanup path can call this.
     */
}

static void vu_gpio_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
{
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);

    vhost_virtqueue_mask(&gpio->vhost_dev, vdev, idx, mask);
}

static void do_vhost_user_cleanup(VirtIODevice *vdev, VHostUserGPIO *gpio)
{
    virtio_delete_queue(gpio->command_vq);
    virtio_delete_queue(gpio->interrupt_vq);
    g_free(gpio->vhost_dev.vqs);
    gpio->vhost_dev.vqs = NULL;
    virtio_cleanup(vdev);
    vhost_user_cleanup(&gpio->vhost_user);
}

static int vu_gpio_connect(DeviceState *dev, Error **errp)
{
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
    struct vhost_dev *vhost_dev = &gpio->vhost_dev;
    int ret;

    if (gpio->connected) {
        return 0;
    }
    gpio->connected = true;

    vhost_dev_set_config_notifier(vhost_dev, &gpio_ops);
    gpio->vhost_user.supports_config = true;

    ret = vhost_dev_init(vhost_dev, &gpio->vhost_user,
                         VHOST_BACKEND_TYPE_USER, 0, errp);
    if (ret < 0) {
        return ret;
    }

    /* restore vhost state */
    if (virtio_device_started(vdev, vdev->status)) {
        vu_gpio_start(vdev);
    }

    return 0;
}

static void vu_gpio_disconnect(DeviceState *dev)
{
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);

    if (!gpio->connected) {
        return;
    }
    gpio->connected = false;

    vu_gpio_stop(vdev);
    vhost_dev_cleanup(&gpio->vhost_dev);
}

static void vu_gpio_event(void *opaque, QEMUChrEvent event)
{
    DeviceState *dev = opaque;
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
    Error *local_err = NULL;

    switch (event) {
    case CHR_EVENT_OPENED:
        if (vu_gpio_connect(dev, &local_err) < 0) {
            qemu_chr_fe_disconnect(&gpio->chardev);
            return;
        }
        break;
    case CHR_EVENT_CLOSED:
        vu_gpio_disconnect(dev);
        break;
    case CHR_EVENT_BREAK:
    case CHR_EVENT_MUX_IN:
    case CHR_EVENT_MUX_OUT:
        /* Ignore */
        break;
    }
}

static int vu_gpio_realize_connect(VHostUserGPIO *gpio, Error **errp)
{
    VirtIODevice *vdev = &gpio->parent_obj;
    DeviceState *dev = &vdev->parent_obj;
    struct vhost_dev *vhost_dev = &gpio->vhost_dev;
    int ret;

    ret = qemu_chr_fe_wait_connected(&gpio->chardev, errp);
    if (ret < 0) {
        return ret;
    }

    /*
     * vu_gpio_connect() may have already connected (via the event
     * callback) in which case it will just report success.
     */
    ret = vu_gpio_connect(dev, errp);
    if (ret < 0) {
        qemu_chr_fe_disconnect(&gpio->chardev);
        return ret;
    }
    g_assert(gpio->connected);

    ret = vhost_dev_get_config(vhost_dev, (uint8_t *)&gpio->config,
                               sizeof(gpio->config), errp);

    if (ret < 0) {
        error_report("vhost-user-gpio: get config failed");

        qemu_chr_fe_disconnect(&gpio->chardev);
        vhost_dev_cleanup(vhost_dev);
        return ret;
    }

    return 0;
}

static void vu_gpio_device_realize(DeviceState *dev, Error **errp)
{
    ERRP_GUARD();

    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VHostUserGPIO *gpio = VHOST_USER_GPIO(dev);
    int retries, ret;

    if (!gpio->chardev.chr) {
        error_setg(errp, "vhost-user-gpio: chardev is mandatory");
        return;
    }

    if (!vhost_user_init(&gpio->vhost_user, &gpio->chardev, errp)) {
        return;
    }

    virtio_init(vdev, VIRTIO_ID_GPIO, sizeof(gpio->config));

    gpio->vhost_dev.nvqs = 2;
    gpio->command_vq = virtio_add_queue(vdev, 256, vu_gpio_handle_output);
    gpio->interrupt_vq = virtio_add_queue(vdev, 256, vu_gpio_handle_output);
    gpio->vhost_dev.vqs = g_new0(struct vhost_virtqueue, gpio->vhost_dev.nvqs);

    gpio->connected = false;

    qemu_chr_fe_set_handlers(&gpio->chardev, NULL, NULL, vu_gpio_event, NULL,
                             dev, NULL, true);

    retries = REALIZE_CONNECTION_RETRIES;
    g_assert(!*errp);
    do {
        if (*errp) {
            error_prepend(errp, "Reconnecting after error: ");
            error_report_err(*errp);
            *errp = NULL;
        }
        ret = vu_gpio_realize_connect(gpio, errp);
    } while (ret < 0 && retries--);

    if (ret < 0) {
        do_vhost_user_cleanup(vdev, gpio);
    }

    return;
}

static void vu_gpio_device_unrealize(DeviceState *dev)
{
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VHostUserGPIO *gpio = VHOST_USER_GPIO(dev);

    vu_gpio_set_status(vdev, 0);
    qemu_chr_fe_set_handlers(&gpio->chardev, NULL, NULL, NULL, NULL, NULL, NULL,
                             false);
    vhost_dev_cleanup(&gpio->vhost_dev);
    do_vhost_user_cleanup(vdev, gpio);
}

static const VMStateDescription vu_gpio_vmstate = {
    .name = "vhost-user-gpio",
    .unmigratable = 1,
};

static Property vu_gpio_properties[] = {
    DEFINE_PROP_CHR("chardev", VHostUserGPIO, chardev),
    DEFINE_PROP_END_OF_LIST(),
};

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

    device_class_set_props(dc, vu_gpio_properties);
    dc->vmsd = &vu_gpio_vmstate;
    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
    vdc->realize = vu_gpio_device_realize;
    vdc->unrealize = vu_gpio_device_unrealize;
    vdc->get_features = vu_gpio_get_features;
    vdc->get_config = vu_gpio_get_config;
    vdc->set_status = vu_gpio_set_status;
    vdc->guest_notifier_mask = vu_gpio_guest_notifier_mask;
}

static const TypeInfo vu_gpio_info = {
    .name = TYPE_VHOST_USER_GPIO,
    .parent = TYPE_VIRTIO_DEVICE,
    .instance_size = sizeof(VHostUserGPIO),
    .class_init = vu_gpio_class_init,
};

static void vu_gpio_register_types(void)
{
    type_register_static(&vu_gpio_info);
}

type_init(vu_gpio_register_types)
Commit	Line	Data
27ba7b02 VK	1	/*
	2	* Vhost-user GPIO virtio device
	3	*
	4	* Copyright (c) 2022 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-gpio.h"
	14	#include "qemu/error-report.h"
	15	#include "standard-headers/linux/virtio_ids.h"
	16	#include "trace.h"
	17
	18	#define REALIZE_CONNECTION_RETRIES 3
	19
	20	/* Features required from VirtIO */
	21	static const int feature_bits[] = {
	22	VIRTIO_F_VERSION_1,
	23	VIRTIO_F_NOTIFY_ON_EMPTY,
	24	VIRTIO_RING_F_INDIRECT_DESC,
	25	VIRTIO_RING_F_EVENT_IDX,
	26	VIRTIO_GPIO_F_IRQ,
562a7d23	27	VIRTIO_F_RING_RESET,
27ba7b02 VK	28	VHOST_INVALID_FEATURE_BIT
	29	};
	30
	31	static void vu_gpio_get_config(VirtIODevice vdev, uint8_t config)
	32	{
	33	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
	34
	35	memcpy(config, &gpio->config, sizeof(gpio->config));
	36	}
	37
	38	static int vu_gpio_config_notifier(struct vhost_dev *dev)
	39	{
	40	VHostUserGPIO *gpio = VHOST_USER_GPIO(dev->vdev);
	41
	42	memcpy(dev->vdev->config, &gpio->config, sizeof(gpio->config));
	43	virtio_notify_config(dev->vdev);
	44
	45	return 0;
	46	}
	47
	48	const VhostDevConfigOps gpio_ops = {
	49	.vhost_dev_config_notifier = vu_gpio_config_notifier,
	50	};
	51
	52	static int vu_gpio_start(VirtIODevice *vdev)
	53	{
	54	BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
	55	VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
	56	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
	57	struct vhost_dev *vhost_dev = &gpio->vhost_dev;
	58	int ret, i;
	59
	60	if (!k->set_guest_notifiers) {
	61	error_report("binding does not support guest notifiers");
	62	return -ENOSYS;
	63	}
	64
	65	ret = vhost_dev_enable_notifiers(vhost_dev, vdev);
	66	if (ret < 0) {
	67	error_report("Error enabling host notifiers: %d", ret);
	68	return ret;
	69	}
	70
	71	ret = k->set_guest_notifiers(qbus->parent, vhost_dev->nvqs, true);
	72	if (ret < 0) {
	73	error_report("Error binding guest notifier: %d", ret);
	74	goto err_host_notifiers;
	75	}
	76
	77	/*
	78	* Before we start up we need to ensure we have the final feature
	79	* set needed for the vhost configuration. The backend may also
	80	* apply backend_features when the feature set is sent.
	81	*/
	82	vhost_ack_features(&gpio->vhost_dev, feature_bits, vdev->guest_features);
	83
4daa5054	84	ret = vhost_dev_start(&gpio->vhost_dev, vdev, false);
27ba7b02 VK	85	if (ret < 0) {
	86	error_report("Error starting vhost-user-gpio: %d", ret);
	87	goto err_guest_notifiers;
	88	}
060f4a94	89	gpio->started_vu = true;
27ba7b02 VK	90
	91	/*
	92	* guest_notifier_mask/pending not used yet, so just unmask
	93	* everything here. virtio-pci will do the right thing by
	94	* enabling/disabling irqfd.
	95	*/
	96	for (i = 0; i < gpio->vhost_dev.nvqs; i++) {
	97	vhost_virtqueue_mask(&gpio->vhost_dev, vdev, i, false);
	98	}
	99
	100	/*
	101	* As we must have VHOST_USER_F_PROTOCOL_FEATURES (because
	102	* VHOST_USER_GET_CONFIG requires it) we need to explicitly enable
	103	* the vrings.
	104	*/
	105	g_assert(vhost_dev->vhost_ops &&
	106	vhost_dev->vhost_ops->vhost_set_vring_enable);
	107	ret = vhost_dev->vhost_ops->vhost_set_vring_enable(vhost_dev, true);
	108	if (ret == 0) {
	109	return 0;
	110	}
	111
	112	error_report("Failed to start vrings for vhost-user-gpio: %d", ret);
	113
	114	err_guest_notifiers:
	115	k->set_guest_notifiers(qbus->parent, gpio->vhost_dev.nvqs, false);
	116	err_host_notifiers:
	117	vhost_dev_disable_notifiers(&gpio->vhost_dev, vdev);
	118
	119	return ret;
	120	}
	121
	122	static void vu_gpio_stop(VirtIODevice *vdev)
	123	{
	124	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
	125	BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
	126	VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
	127	struct vhost_dev *vhost_dev = &gpio->vhost_dev;
	128	int ret;
	129
060f4a94	130	if (!gpio->started_vu) {
27ba7b02 VK	131	return;
27ba7b02 VK	132	}
060f4a94	133	gpio->started_vu = false;
27ba7b02	134
060f4a94	135	if (!k->set_guest_notifiers) {
27ba7b02 VK	136	return;
	137	}
	138
4daa5054	139	vhost_dev_stop(vhost_dev, vdev, false);
27ba7b02 VK	140
	141	ret = k->set_guest_notifiers(qbus->parent, vhost_dev->nvqs, false);
	142	if (ret < 0) {
	143	error_report("vhost guest notifier cleanup failed: %d", ret);
	144	return;
	145	}
	146
	147	vhost_dev_disable_notifiers(vhost_dev, vdev);
	148	}
	149
	150	static void vu_gpio_set_status(VirtIODevice *vdev, uint8_t status)
	151	{
	152	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
259d69c0	153	bool should_start = virtio_device_should_start(vdev, status);
27ba7b02 VK	154
	155	trace_virtio_gpio_set_status(status);
	156
	157	if (!gpio->connected) {
	158	return;
	159	}
	160
	161	if (vhost_dev_is_started(&gpio->vhost_dev) == should_start) {
	162	return;
	163	}
	164
	165	if (should_start) {
	166	if (vu_gpio_start(vdev)) {
	167	qemu_chr_fe_disconnect(&gpio->chardev);
	168	}
	169	} else {
	170	vu_gpio_stop(vdev);
	171	}
	172	}
	173
	174	static uint64_t vu_gpio_get_features(VirtIODevice *vdev, uint64_t features,
	175	Error **errp)
	176	{
	177	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
	178
	179	return vhost_get_features(&gpio->vhost_dev, feature_bits, features);
	180	}
	181
	182	static void vu_gpio_handle_output(VirtIODevice vdev, VirtQueue vq)
	183	{
	184	/*
	185	* Not normally called; it's the daemon that handles the queue;
	186	* however virtio's cleanup path can call this.
	187	*/
	188	}
	189
	190	static void vu_gpio_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
	191	{
	192	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
	193
	194	vhost_virtqueue_mask(&gpio->vhost_dev, vdev, idx, mask);
	195	}
	196
	197	static void do_vhost_user_cleanup(VirtIODevice vdev, VHostUserGPIO gpio)
	198	{
	199	virtio_delete_queue(gpio->command_vq);
	200	virtio_delete_queue(gpio->interrupt_vq);
	201	g_free(gpio->vhost_dev.vqs);
	202	gpio->vhost_dev.vqs = NULL;
	203	virtio_cleanup(vdev);
	204	vhost_user_cleanup(&gpio->vhost_user);
	205	}
	206
	207	static int vu_gpio_connect(DeviceState dev, Error *errp)
	208	{
	209	VirtIODevice *vdev = VIRTIO_DEVICE(dev);
	210	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
	211	struct vhost_dev *vhost_dev = &gpio->vhost_dev;
	212	int ret;
	213
	214	if (gpio->connected) {
	215	return 0;
	216	}
	217	gpio->connected = true;
218
219	vhost_dev_set_config_notifier(vhost_dev, &gpio_ops);
220	gpio->vhost_user.supports_config = true;
221
222	ret = vhost_dev_init(vhost_dev, &gpio->vhost_user,
223	VHOST_BACKEND_TYPE_USER, 0, errp);
224	if (ret < 0) {
225	return ret;
226	}
227
228	/* restore vhost state */
229	if (virtio_device_started(vdev, vdev->status)) {
230	vu_gpio_start(vdev);
231	}
232
233	return 0;
234	}
235
236	static void vu_gpio_disconnect(DeviceState *dev)
237	{
238	VirtIODevice *vdev = VIRTIO_DEVICE(dev);
239	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
240
241	if (!gpio->connected) {
242	return;
243	}
244	gpio->connected = false;
245
246	vu_gpio_stop(vdev);
247	vhost_dev_cleanup(&gpio->vhost_dev);
248	}
249
250	static void vu_gpio_event(void *opaque, QEMUChrEvent event)
251	{
252	DeviceState *dev = opaque;
253	VirtIODevice *vdev = VIRTIO_DEVICE(dev);
254	VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
255	Error *local_err = NULL;
256
257	switch (event) {
258	case CHR_EVENT_OPENED:
259	if (vu_gpio_connect(dev, &local_err) < 0) {
260	qemu_chr_fe_disconnect(&gpio->chardev);
261	return;
262	}
263	break;
264	case CHR_EVENT_CLOSED:
265	vu_gpio_disconnect(dev);
266	break;
267	case CHR_EVENT_BREAK:
268	case CHR_EVENT_MUX_IN:
269	case CHR_EVENT_MUX_OUT:
270	/* Ignore */
271	break;
272	}
273	}
274
275	static int vu_gpio_realize_connect(VHostUserGPIO gpio, Error *errp)
276	{
277	VirtIODevice *vdev = &gpio->parent_obj;
278	DeviceState *dev = &vdev->parent_obj;
279	struct vhost_dev *vhost_dev = &gpio->vhost_dev;
280	int ret;
281
282	ret = qemu_chr_fe_wait_connected(&gpio->chardev, errp);
283	if (ret < 0) {
284	return ret;
285	}
286
287	/*
288	* vu_gpio_connect() may have already connected (via the event
289	* callback) in which case it will just report success.
290	*/
291	ret = vu_gpio_connect(dev, errp);
292	if (ret < 0) {
293	qemu_chr_fe_disconnect(&gpio->chardev);
294	return ret;
295	}
296	g_assert(gpio->connected);
297
298	ret = vhost_dev_get_config(vhost_dev, (uint8_t *)&gpio->config,
299	sizeof(gpio->config), errp);
300
301	if (ret < 0) {
302	error_report("vhost-user-gpio: get config failed");
303
304	qemu_chr_fe_disconnect(&gpio->chardev);
305	vhost_dev_cleanup(vhost_dev);
306	return ret;
307	}
308
309	return 0;
310	}
311
312	static void vu_gpio_device_realize(DeviceState dev, Error *errp)
313	{
314	ERRP_GUARD();
315
316	VirtIODevice *vdev = VIRTIO_DEVICE(dev);
317	VHostUserGPIO *gpio = VHOST_USER_GPIO(dev);
318	int retries, ret;
319
320	if (!gpio->chardev.chr) {
321	error_setg(errp, "vhost-user-gpio: chardev is mandatory");
322	return;
323	}
324
325	if (!vhost_user_init(&gpio->vhost_user, &gpio->chardev, errp)) {
326	return;
327	}
328
329	virtio_init(vdev, VIRTIO_ID_GPIO, sizeof(gpio->config));
330
331	gpio->vhost_dev.nvqs = 2;
332	gpio->command_vq = virtio_add_queue(vdev, 256, vu_gpio_handle_output);
333	gpio->interrupt_vq = virtio_add_queue(vdev, 256, vu_gpio_handle_output);
334	gpio->vhost_dev.vqs = g_new0(struct vhost_virtqueue, gpio->vhost_dev.nvqs);
335
336	gpio->connected = false;
337
338	qemu_chr_fe_set_handlers(&gpio->chardev, NULL, NULL, vu_gpio_event, NULL,
339	dev, NULL, true);
340
341	retries = REALIZE_CONNECTION_RETRIES;
342	g_assert(!*errp);
343	do {
344	if (*errp) {
345	error_prepend(errp, "Reconnecting after error: ");
346	error_report_err(*errp);
347	*errp = NULL;
348	}
349	ret = vu_gpio_realize_connect(gpio, errp);
350	} while (ret < 0 && retries--);
351
352	if (ret < 0) {
353	do_vhost_user_cleanup(vdev, gpio);
354	}
355
356	return;
357	}
358
359	static void vu_gpio_device_unrealize(DeviceState *dev)
360	{
361	VirtIODevice *vdev = VIRTIO_DEVICE(dev);
362	VHostUserGPIO *gpio = VHOST_USER_GPIO(dev);
363
364	vu_gpio_set_status(vdev, 0);
365	qemu_chr_fe_set_handlers(&gpio->chardev, NULL, NULL, NULL, NULL, NULL, NULL,
366	false);
367	vhost_dev_cleanup(&gpio->vhost_dev);
368	do_vhost_user_cleanup(vdev, gpio);
369	}
370
371	static const VMStateDescription vu_gpio_vmstate = {
372	.name = "vhost-user-gpio",
373	.unmigratable = 1,
374	};
375
376	static Property vu_gpio_properties[] = {
377	DEFINE_PROP_CHR("chardev", VHostUserGPIO, chardev),
378	DEFINE_PROP_END_OF_LIST(),
379	};
380
381	static void vu_gpio_class_init(ObjectClass klass, void data)
382	{
383	DeviceClass *dc = DEVICE_CLASS(klass);
384	VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
385
386	device_class_set_props(dc, vu_gpio_properties);
387	dc->vmsd = &vu_gpio_vmstate;
388	set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
389	vdc->realize = vu_gpio_device_realize;
390	vdc->unrealize = vu_gpio_device_unrealize;
391	vdc->get_features = vu_gpio_get_features;
392	vdc->get_config = vu_gpio_get_config;
393	vdc->set_status = vu_gpio_set_status;
394	vdc->guest_notifier_mask = vu_gpio_guest_notifier_mask;
395	}
396
397	static const TypeInfo vu_gpio_info = {
398	.name = TYPE_VHOST_USER_GPIO,
399	.parent = TYPE_VIRTIO_DEVICE,
400	.instance_size = sizeof(VHostUserGPIO),
401	.class_init = vu_gpio_class_init,
402	};
403
404	static void vu_gpio_register_types(void)
405	{
406	type_register_static(&vu_gpio_info);
407	}
408
409	type_init(vu_gpio_register_types)