1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/virtio.h>
11 /* Unique numbering for virtio devices. */
14 static ssize_t device_show(struct device *_d,  in device_show()
18 	return sysfs_emit(buf, "0x%04x\n", dev->id.device);  in device_show()
20 static DEVICE_ATTR_RO(device);
22 static ssize_t vendor_show(struct device *_d,  in vendor_show()
26 	return sysfs_emit(buf, "0x%04x\n", dev->id.vendor);  in vendor_show()
30 static ssize_t status_show(struct device *_d,  in status_show()
34 	return sysfs_emit(buf, "0x%08x\n", dev->config->get_status(dev));  in status_show()
38 static ssize_t modalias_show(struct device *_d,  in modalias_show()
42 	return sysfs_emit(buf, "virtio:d%08Xv%08X\n",  in modalias_show()
43 		       dev->id.device, dev->id.vendor);  in modalias_show()
47 static ssize_t features_show(struct device *_d,  in features_show()
56 	for (i = 0; i < sizeof(dev->features)*8; i++)  in features_show()
77 	if (id->device != dev->id.device && id->device != VIRTIO_DEV_ANY_ID)  in virtio_id_match()
80 	return id->vendor == VIRTIO_DEV_ANY_ID || id->vendor == dev->id.vendor;  in virtio_id_match()
85 static int virtio_dev_match(struct device *_dv, const struct device_driver *_dr)  in virtio_dev_match()
91 	ids = drv_to_virtio(_dr)->id_table;  in virtio_dev_match()
92 	for (i = 0; ids[i].device; i++)  in virtio_dev_match()
98 static int virtio_uevent(const struct device *_dv, struct kobj_uevent_env *env)  in virtio_uevent()
102 	return add_uevent_var(env, "MODALIAS=virtio:d%08Xv%08X",  in virtio_uevent()
103 			      dev->id.device, dev->id.vendor);  in virtio_uevent()
110 	struct virtio_driver *drv = drv_to_virtio(vdev->dev.driver);  in virtio_check_driver_offered_feature()
112 	for (i = 0; i < drv->feature_table_size; i++)  in virtio_check_driver_offered_feature()
113 		if (drv->feature_table[i] == fbit)  in virtio_check_driver_offered_feature()
116 	if (drv->feature_table_legacy) {  in virtio_check_driver_offered_feature()
117 		for (i = 0; i < drv->feature_table_size_legacy; i++)  in virtio_check_driver_offered_feature()
118 			if (drv->feature_table_legacy[i] == fbit)  in virtio_check_driver_offered_feature()
128 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in __virtio_config_changed()
130 	if (!dev->config_core_enabled || dev->config_driver_disabled)  in __virtio_config_changed()
131 		dev->config_change_pending = true;  in __virtio_config_changed()
132 	else if (drv && drv->config_changed) {  in __virtio_config_changed()
133 		drv->config_changed(dev);  in __virtio_config_changed()
134 		dev->config_change_pending = false;  in __virtio_config_changed()
142 	spin_lock_irqsave(&dev->config_lock, flags);  in virtio_config_changed()
144 	spin_unlock_irqrestore(&dev->config_lock, flags);  in virtio_config_changed()
149  * virtio_config_driver_disable - disable config change reporting by drivers
150  * @dev: the device to reset
157 	spin_lock_irq(&dev->config_lock);  in virtio_config_driver_disable()
158 	dev->config_driver_disabled = true;  in virtio_config_driver_disable()
159 	spin_unlock_irq(&dev->config_lock);  in virtio_config_driver_disable()
164  * virtio_config_driver_enable - enable config change reporting by drivers
165  * @dev: the device to reset
172 	spin_lock_irq(&dev->config_lock);  in virtio_config_driver_enable()
173 	dev->config_driver_disabled = false;  in virtio_config_driver_enable()
174 	if (dev->config_change_pending)  in virtio_config_driver_enable()
176 	spin_unlock_irq(&dev->config_lock);  in virtio_config_driver_enable()
182 	spin_lock_irq(&dev->config_lock);  in virtio_config_core_disable()
183 	dev->config_core_enabled = false;  in virtio_config_core_disable()
184 	spin_unlock_irq(&dev->config_lock);  in virtio_config_core_disable()
189 	spin_lock_irq(&dev->config_lock);  in virtio_config_core_enable()
190 	dev->config_core_enabled = true;  in virtio_config_core_enable()
191 	if (dev->config_change_pending)  in virtio_config_core_enable()
193 	spin_unlock_irq(&dev->config_lock);  in virtio_config_core_enable()
199 	dev->config->set_status(dev, dev->config->get_status(dev) | status);  in virtio_add_status()
212 			dev_warn(&dev->dev,  in virtio_features_ok()
213 				 "device must provide VIRTIO_F_VERSION_1\n");  in virtio_features_ok()
214 			return -ENODEV;  in virtio_features_ok()
218 			dev_warn(&dev->dev,  in virtio_features_ok()
219 				 "device must provide VIRTIO_F_ACCESS_PLATFORM\n");  in virtio_features_ok()
220 			return -ENODEV;  in virtio_features_ok()
228 	status = dev->config->get_status(dev);  in virtio_features_ok()
230 		dev_err(&dev->dev, "virtio: device refuses features: %x\n",  in virtio_features_ok()
232 		return -ENODEV;  in virtio_features_ok()
238  * virtio_reset_device - quiesce device for removal
239  * @dev: the device to reset
241  * Prevents device from sending interrupts and accessing memory.
243  * Generally used for cleanup during driver / device removal.
260 	 * vq->broken as true.  in virtio_reset_device()
266 	dev->config->reset(dev);  in virtio_reset_device()
270 static int virtio_dev_probe(struct device *_d)  in virtio_dev_probe()
274 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_dev_probe()
282 	/* Figure out what features the device supports. */  in virtio_dev_probe()
283 	device_features = dev->config->get_features(dev);  in virtio_dev_probe()
287 	for (i = 0; i < drv->feature_table_size; i++) {  in virtio_dev_probe()
288 		unsigned int f = drv->feature_table[i];  in virtio_dev_probe()
293 	/* Some drivers have a separate feature table for virtio v1.0 */  in virtio_dev_probe()
294 	if (drv->feature_table_legacy) {  in virtio_dev_probe()
296 		for (i = 0; i < drv->feature_table_size_legacy; i++) {  in virtio_dev_probe()
297 			unsigned int f = drv->feature_table_legacy[i];  in virtio_dev_probe()
306 		dev->features = driver_features & device_features;  in virtio_dev_probe()
308 		dev->features = driver_features_legacy & device_features;  in virtio_dev_probe()
318 	err = dev->config->finalize_features(dev);  in virtio_dev_probe()
322 	if (drv->validate) {  in virtio_dev_probe()
323 		u64 features = dev->features;  in virtio_dev_probe()
325 		err = drv->validate(dev);  in virtio_dev_probe()
330 		if (features != dev->features) {  in virtio_dev_probe()
331 			err = dev->config->finalize_features(dev);  in virtio_dev_probe()
341 	err = drv->probe(dev);  in virtio_dev_probe()
345 	/* If probe didn't do it, mark device DRIVER_OK ourselves. */  in virtio_dev_probe()
346 	if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))  in virtio_dev_probe()
349 	if (drv->scan)  in virtio_dev_probe()
350 		drv->scan(dev);  in virtio_dev_probe()
362 static void virtio_dev_remove(struct device *_d)  in virtio_dev_remove()
365 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_dev_remove()
369 	drv->remove(dev);  in virtio_dev_remove()
371 	/* Driver should have reset device. */  in virtio_dev_remove()
372 	WARN_ON_ONCE(dev->config->get_status(dev));  in virtio_dev_remove()
374 	/* Acknowledge the device's existence again. */  in virtio_dev_remove()
377 	of_node_put(dev->dev.of_node);  in virtio_dev_remove()
381 	.name  = "virtio",
392 	BUG_ON(driver->feature_table_size && !driver->feature_table);  in __register_virtio_driver()
393 	driver->driver.bus = &virtio_bus;  in __register_virtio_driver()
394 	driver->driver.owner = owner;  in __register_virtio_driver()
396 	return driver_register(&driver->driver);  in __register_virtio_driver()
402 	driver_unregister(&driver->driver);  in unregister_virtio_driver()
408 	struct device_node *np, *pnode = dev_of_node(dev->dev.parent);  in virtio_device_of_init()
409 	char compat[] = "virtio,deviceXXXXXXXX";  in virtio_device_of_init()
421 		return -EINVAL;  in virtio_device_of_init()
425 		return -ENODEV;  in virtio_device_of_init()
427 	ret = snprintf(compat, sizeof(compat), "virtio,device%x", dev->id.device);  in virtio_device_of_init()
431 	 * On powerpc/pseries virtio devices are PCI devices so PCI  in virtio_device_of_init()
432 	 * vendor/device ids play the role of the "compatible" property.  in virtio_device_of_init()
440 	dev->dev.of_node = np;  in virtio_device_of_init()
449  * register_virtio_device - register virtio device
450  * @dev        : virtio device to be registered
452  * On error, the caller must call put_device on &@dev->dev (and not kfree),
455  * Returns: 0 on suceess, -error on failure
461 	dev->dev.bus = &virtio_bus;  in register_virtio_device()
462 	device_initialize(&dev->dev);  in register_virtio_device()
464 	/* Assign a unique device index and hence name. */  in register_virtio_device()
469 	dev->index = err;  in register_virtio_device()
470 	err = dev_set_name(&dev->dev, "virtio%u", dev->index);  in register_virtio_device()
478 	spin_lock_init(&dev->config_lock);  in register_virtio_device()
479 	dev->config_core_enabled = false;  in register_virtio_device()
480 	dev->config_change_pending = false;  in register_virtio_device()
482 	INIT_LIST_HEAD(&dev->vqs);  in register_virtio_device()
483 	spin_lock_init(&dev->vqs_list_lock);  in register_virtio_device()
485 	/* We always start by resetting the device, in case a previous  in register_virtio_device()
489 	/* Acknowledge that we've seen the device. */  in register_virtio_device()
498 	err = device_add(&dev->dev);  in register_virtio_device()
505 	of_node_put(dev->dev.of_node);  in register_virtio_device()
507 	ida_free(&virtio_index_ida, dev->index);  in register_virtio_device()
514 bool is_virtio_device(struct device *dev)  in is_virtio_device()
516 	return dev->bus == &virtio_bus;  in is_virtio_device()
522 	int index = dev->index; /* save for after device release */  in unregister_virtio_device()
524 	device_unregister(&dev->dev);  in unregister_virtio_device()
533 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_device_freeze()
538 	dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;  in virtio_device_freeze()
540 	if (drv && drv->freeze) {  in virtio_device_freeze()
541 		ret = drv->freeze(dev);  in virtio_device_freeze()
554 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);  in virtio_device_restore()
557 	/* We always start by resetting the device, in case a previous  in virtio_device_restore()
561 	/* Acknowledge that we've seen the device. */  in virtio_device_restore()
566 	if (dev->failed)  in virtio_device_restore()
575 	ret = dev->config->finalize_features(dev);  in virtio_device_restore()
583 	if (drv->restore) {  in virtio_device_restore()
584 		ret = drv->restore(dev);  in virtio_device_restore()
589 	/* If restore didn't do it, mark device DRIVER_OK ourselves. */  in virtio_device_restore()
590 	if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))  in virtio_device_restore()
607 		panic("virtio bus registration failed");  in virtio_init()
621 MODULE_DESCRIPTION("Virtio core interface");