1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/virtio.h>
10 /* Unique numbering for virtio devices. */
13 static ssize_t device_show(struct device *_d,  in device_show()
17 	return sprintf(buf, "0x%04x\n", dev->id.device);  in device_show()
19 static DEVICE_ATTR_RO(device);
21 static ssize_t vendor_show(struct device *_d,  in vendor_show()
25 	return sprintf(buf, "0x%04x\n", dev->id.vendor);  in vendor_show()
29 static ssize_t status_show(struct device *_d,  in status_show()
33 	return sprintf(buf, "0x%08x\n", dev->config->get_status(dev));  in status_show()
37 static ssize_t modalias_show(struct device *_d,  in modalias_show()
41 	return sprintf(buf, "virtio:d%08Xv%08X\n",  in modalias_show()
42 		       dev->id.device, dev->id.vendor);  in modalias_show()
46 static ssize_t features_show(struct device *_d,  in features_show()
55 	for (i = 0; i < sizeof(dev->features)*8; i++)  in features_show()
76 	if (id->device != dev->id.device && id->device != VIRTIO_DEV_ANY_ID)  in virtio_id_match()
79 	return id->vendor == VIRTIO_DEV_ANY_ID || id->vendor == dev->id.vendor;  in virtio_id_match()
84 static int virtio_dev_match(struct device *_dv, struct device_driver *_dr)  in virtio_dev_match()
90 	ids = drv_to_virtio(_dr)->id_table;  in virtio_dev_match()
91 	for (i = 0; ids[i].device; i++)  in virtio_dev_match()
97 static int virtio_uevent(struct device *_dv, struct kobj_uevent_env *env)  in virtio_uevent()
101 	return add_uevent_var(env, "MODALIAS=virtio:d%08Xv%08X",  in virtio_uevent()
102 			      dev->id.device, dev->id.vendor);  in virtio_uevent()
109 	struct virtio_driver *drv = drv_to_virtio(vdev->dev.driver);  in virtio_check_driver_offered_feature()
111 	for (i = 0; i < drv->feature_table_size; i++)  in virtio_check_driver_offered_feature()
112 		if (drv->feature_table[i] == fbit)  in virtio_check_driver_offered_feature()
115 	if (drv->feature_table_legacy) {  in virtio_check_driver_offered_feature()
116 		for (i = 0; i < drv->feature_table_size_legacy; i++)  in virtio_check_driver_offered_feature()
117 			if (drv->feature_table_legacy[i] == fbit)  in virtio_check_driver_offered_feature()
127 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in __virtio_config_changed()
129 	if (!dev->config_enabled)  in __virtio_config_changed()
130 		dev->config_change_pending = true;  in __virtio_config_changed()
131 	else if (drv && drv->config_changed)  in __virtio_config_changed()
132 		drv->config_changed(dev);  in __virtio_config_changed()
139 	spin_lock_irqsave(&dev->config_lock, flags);  in virtio_config_changed()
141 	spin_unlock_irqrestore(&dev->config_lock, flags);  in virtio_config_changed()
147 	spin_lock_irq(&dev->config_lock);  in virtio_config_disable()
148 	dev->config_enabled = false;  in virtio_config_disable()
149 	spin_unlock_irq(&dev->config_lock);  in virtio_config_disable()
154 	spin_lock_irq(&dev->config_lock);  in virtio_config_enable()
155 	dev->config_enabled = true;  in virtio_config_enable()
156 	if (dev->config_change_pending)  in virtio_config_enable()
158 	dev->config_change_pending = false;  in virtio_config_enable()
159 	spin_unlock_irq(&dev->config_lock);  in virtio_config_enable()
165 	dev->config->set_status(dev, dev->config->get_status(dev) | status);  in virtio_add_status()
171 	int ret = dev->config->finalize_features(dev);  in virtio_finalize_features()
181 			dev_warn(&dev->dev,  in virtio_finalize_features()
182 				 "device must provide VIRTIO_F_VERSION_1\n");  in virtio_finalize_features()
183 			return -ENODEV;  in virtio_finalize_features()
187 			dev_warn(&dev->dev,  in virtio_finalize_features()
188 				 "device must provide VIRTIO_F_ACCESS_PLATFORM\n");  in virtio_finalize_features()
189 			return -ENODEV;  in virtio_finalize_features()
197 	status = dev->config->get_status(dev);  in virtio_finalize_features()
199 		dev_err(&dev->dev, "virtio: device refuses features: %x\n",  in virtio_finalize_features()
201 		return -ENODEV;  in virtio_finalize_features()
207 static int virtio_dev_probe(struct device *_d)  in virtio_dev_probe()
211 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_dev_probe()
219 	/* Figure out what features the device supports. */  in virtio_dev_probe()
220 	device_features = dev->config->get_features(dev);  in virtio_dev_probe()
224 	for (i = 0; i < drv->feature_table_size; i++) {  in virtio_dev_probe()
225 		unsigned int f = drv->feature_table[i];  in virtio_dev_probe()
230 	/* Some drivers have a separate feature table for virtio v1.0 */  in virtio_dev_probe()
231 	if (drv->feature_table_legacy) {  in virtio_dev_probe()
233 		for (i = 0; i < drv->feature_table_size_legacy; i++) {  in virtio_dev_probe()
234 			unsigned int f = drv->feature_table_legacy[i];  in virtio_dev_probe()
247 	if (drv->validate && !virtio_legacy_is_little_endian()  in virtio_dev_probe()
249 		dev->features = BIT_ULL(VIRTIO_F_VERSION_1);  in virtio_dev_probe()
250 		dev->config->finalize_features(dev);  in virtio_dev_probe()
254 		dev->features = driver_features & device_features;  in virtio_dev_probe()
256 		dev->features = driver_features_legacy & device_features;  in virtio_dev_probe()
263 	if (drv->validate) {  in virtio_dev_probe()
264 		err = drv->validate(dev);  in virtio_dev_probe()
273 	err = drv->probe(dev);  in virtio_dev_probe()
277 	/* If probe didn't do it, mark device DRIVER_OK ourselves. */  in virtio_dev_probe()
278 	if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))  in virtio_dev_probe()
281 	if (drv->scan)  in virtio_dev_probe()
282 		drv->scan(dev);  in virtio_dev_probe()
293 static void virtio_dev_remove(struct device *_d)  in virtio_dev_remove()
296 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_dev_remove()
300 	drv->remove(dev);  in virtio_dev_remove()
302 	/* Driver should have reset device. */  in virtio_dev_remove()
303 	WARN_ON_ONCE(dev->config->get_status(dev));  in virtio_dev_remove()
305 	/* Acknowledge the device's existence again. */  in virtio_dev_remove()
308 	of_node_put(dev->dev.of_node);  in virtio_dev_remove()
312 	.name  = "virtio",
323 	BUG_ON(driver->feature_table_size && !driver->feature_table);  in register_virtio_driver()
324 	driver->driver.bus = &virtio_bus;  in register_virtio_driver()
325 	return driver_register(&driver->driver);  in register_virtio_driver()
331 	driver_unregister(&driver->driver);  in unregister_virtio_driver()
337 	struct device_node *np, *pnode = dev_of_node(dev->dev.parent);  in virtio_device_of_init()
338 	char compat[] = "virtio,deviceXXXXXXXX";  in virtio_device_of_init()
350 		return -EINVAL;  in virtio_device_of_init()
354 		return -ENODEV;  in virtio_device_of_init()
356 	ret = snprintf(compat, sizeof(compat), "virtio,device%x", dev->id.device);  in virtio_device_of_init()
360 	 * On powerpc/pseries virtio devices are PCI devices so PCI  in virtio_device_of_init()
361 	 * vendor/device ids play the role of the "compatible" property.  in virtio_device_of_init()
369 	dev->dev.of_node = np;  in virtio_device_of_init()
378  * register_virtio_device - register virtio device
379  * @dev        : virtio device to be registered
381  * On error, the caller must call put_device on &@dev->dev (and not kfree),
384  * Returns: 0 on suceess, -error on failure
390 	dev->dev.bus = &virtio_bus;  in register_virtio_device()
391 	device_initialize(&dev->dev);  in register_virtio_device()
393 	/* Assign a unique device index and hence name. */  in register_virtio_device()
398 	dev->index = err;  in register_virtio_device()
399 	dev_set_name(&dev->dev, "virtio%u", dev->index);  in register_virtio_device()
405 	spin_lock_init(&dev->config_lock);  in register_virtio_device()
406 	dev->config_enabled = false;  in register_virtio_device()
407 	dev->config_change_pending = false;  in register_virtio_device()
409 	/* We always start by resetting the device, in case a previous  in register_virtio_device()
411 	dev->config->reset(dev);  in register_virtio_device()
413 	/* Acknowledge that we've seen the device. */  in register_virtio_device()
416 	INIT_LIST_HEAD(&dev->vqs);  in register_virtio_device()
417 	spin_lock_init(&dev->vqs_list_lock);  in register_virtio_device()
423 	err = device_add(&dev->dev);  in register_virtio_device()
430 	of_node_put(dev->dev.of_node);  in register_virtio_device()
432 	ida_simple_remove(&virtio_index_ida, dev->index);  in register_virtio_device()
439 bool is_virtio_device(struct device *dev)  in is_virtio_device()
441 	return dev->bus == &virtio_bus;  in is_virtio_device()
447 	int index = dev->index; /* save for after device release */  in unregister_virtio_device()
449 	device_unregister(&dev->dev);  in unregister_virtio_device()
457 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_device_freeze()
461 	dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;  in virtio_device_freeze()
463 	if (drv && drv->freeze)  in virtio_device_freeze()
464 		return drv->freeze(dev);  in virtio_device_freeze()
472 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_device_restore()
475 	/* We always start by resetting the device, in case a previous  in virtio_device_restore()
477 	dev->config->reset(dev);  in virtio_device_restore()
479 	/* Acknowledge that we've seen the device. */  in virtio_device_restore()
484 	if (dev->failed)  in virtio_device_restore()
497 	if (drv->restore) {  in virtio_device_restore()
498 		ret = drv->restore(dev);  in virtio_device_restore()
503 	/* Finally, tell the device we're all set */  in virtio_device_restore()
520 		panic("virtio bus registration failed");  in virtio_init()