[net-next-2.6.git] / drivers / virtio / virtio.c

#include <linux/virtio.h>
#include <linux/spinlock.h>
#include <linux/virtio_config.h>

/* Unique numbering for virtio devices. */
static unsigned int dev_index;

static ssize_t device_show(struct device *_d,
			   struct device_attribute *attr, char *buf)
{
	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	return sprintf(buf, "%hu", dev->id.device);
}
static ssize_t vendor_show(struct device *_d,
			   struct device_attribute *attr, char *buf)
{
	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	return sprintf(buf, "%hu", dev->id.vendor);
}
static ssize_t status_show(struct device *_d,
			   struct device_attribute *attr, char *buf)
{
	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	return sprintf(buf, "0x%08x", dev->config->get_status(dev));
}
static ssize_t modalias_show(struct device *_d,
			     struct device_attribute *attr, char *buf)
{
	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);

	return sprintf(buf, "virtio:d%08Xv%08X\n",
		       dev->id.device, dev->id.vendor);
}
static ssize_t features_show(struct device *_d,
			     struct device_attribute *attr, char *buf)
{
	struct virtio_device *dev = container_of(_d, struct virtio_device, dev);
	unsigned int i;
	ssize_t len = 0;

	/* We actually represent this as a bitstring, as it could be
	 * arbitrary length in future. */
	for (i = 0; i < ARRAY_SIZE(dev->features)*BITS_PER_LONG; i++)
		len += sprintf(buf+len, "%c",
			       test_bit(i, dev->features) ? '1' : '0');
	len += sprintf(buf+len, "\n");
	return len;
}
static struct device_attribute virtio_dev_attrs[] = {
	__ATTR_RO(device),
	__ATTR_RO(vendor),
	__ATTR_RO(status),
	__ATTR_RO(modalias),
	__ATTR_RO(features),
	__ATTR_NULL
};

static inline int virtio_id_match(const struct virtio_device *dev,
				  const struct virtio_device_id *id)
{
	if (id->device != dev->id.device && id->device != VIRTIO_DEV_ANY_ID)
		return 0;

	return id->vendor == VIRTIO_DEV_ANY_ID || id->vendor == dev->id.vendor;
}

/* This looks through all the IDs a driver claims to support.  If any of them
 * match, we return 1 and the kernel will call virtio_dev_probe(). */
static int virtio_dev_match(struct device *_dv, struct device_driver *_dr)
{
	unsigned int i;
	struct virtio_device *dev = container_of(_dv,struct virtio_device,dev);
	const struct virtio_device_id *ids;

	ids = container_of(_dr, struct virtio_driver, driver)->id_table;
	for (i = 0; ids[i].device; i++)
		if (virtio_id_match(dev, &ids[i]))
			return 1;
	return 0;
}

static int virtio_uevent(struct device *_dv, struct kobj_uevent_env *env)
{
	struct virtio_device *dev = container_of(_dv,struct virtio_device,dev);

	return add_uevent_var(env, "MODALIAS=virtio:d%08Xv%08X",
			      dev->id.device, dev->id.vendor);
}

static void add_status(struct virtio_device *dev, unsigned status)
{
	dev->config->set_status(dev, dev->config->get_status(dev) | status);
}

void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
					 unsigned int fbit)
{
	unsigned int i;
	struct virtio_driver *drv = container_of(vdev->dev.driver,
						 struct virtio_driver, driver);

	for (i = 0; i < drv->feature_table_size; i++)
		if (drv->feature_table[i] == fbit)
			return;
	BUG();
}
EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature);

static int virtio_dev_probe(struct device *_d)
{
	int err, i;
	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	struct virtio_driver *drv = container_of(dev->dev.driver,
						 struct virtio_driver, driver);
	u32 device_features;

	/* We have a driver! */
	add_status(dev, VIRTIO_CONFIG_S_DRIVER);

	/* Figure out what features the device supports. */
	device_features = dev->config->get_features(dev);

	/* Features supported by both device and driver into dev->features. */
	memset(dev->features, 0, sizeof(dev->features));
	for (i = 0; i < drv->feature_table_size; i++) {
		unsigned int f = drv->feature_table[i];
		BUG_ON(f >= 32);
		if (device_features & (1 << f))
			set_bit(f, dev->features);
	}

	/* Transport features always preserved to pass to finalize_features. */
	for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++)
		if (device_features & (1 << i))
			set_bit(i, dev->features);

	dev->config->finalize_features(dev);

	err = drv->probe(dev);
	if (err)
		add_status(dev, VIRTIO_CONFIG_S_FAILED);
	else
		add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);

	return err;
}

static int virtio_dev_remove(struct device *_d)
{
	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	struct virtio_driver *drv = container_of(dev->dev.driver,
						 struct virtio_driver, driver);

	drv->remove(dev);

	/* Driver should have reset device. */
	BUG_ON(dev->config->get_status(dev));

	/* Acknowledge the device's existence again. */
	add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
	return 0;
}

static struct bus_type virtio_bus = {
	.name  = "virtio",
	.match = virtio_dev_match,
	.dev_attrs = virtio_dev_attrs,
	.uevent = virtio_uevent,
	.probe = virtio_dev_probe,
	.remove = virtio_dev_remove,
};

int register_virtio_driver(struct virtio_driver *driver)
{
	/* Catch this early. */
	BUG_ON(driver->feature_table_size && !driver->feature_table);
	driver->driver.bus = &virtio_bus;
	return driver_register(&driver->driver);
}
EXPORT_SYMBOL_GPL(register_virtio_driver);

void unregister_virtio_driver(struct virtio_driver *driver)
{
	driver_unregister(&driver->driver);
}
EXPORT_SYMBOL_GPL(unregister_virtio_driver);

int register_virtio_device(struct virtio_device *dev)
{
	int err;

	dev->dev.bus = &virtio_bus;

	/* Assign a unique device index and hence name. */
	dev->index = dev_index++;
	dev_set_name(&dev->dev, "virtio%u", dev->index);

	/* We always start by resetting the device, in case a previous
	 * driver messed it up.  This also tests that code path a little. */
	dev->config->reset(dev);

	/* Acknowledge that we've seen the device. */
	add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);

	INIT_LIST_HEAD(&dev->vqs);

	/* device_register() causes the bus infrastructure to look for a
	 * matching driver. */
	err = device_register(&dev->dev);
	if (err)
		add_status(dev, VIRTIO_CONFIG_S_FAILED);
	return err;
}
EXPORT_SYMBOL_GPL(register_virtio_device);

void unregister_virtio_device(struct virtio_device *dev)
{
	device_unregister(&dev->dev);
}
EXPORT_SYMBOL_GPL(unregister_virtio_device);

static int virtio_init(void)
{
	if (bus_register(&virtio_bus) != 0)
		panic("virtio bus registration failed");
	return 0;
}

static void __exit virtio_exit(void)
{
	bus_unregister(&virtio_bus);
}
core_initcall(virtio_init);
module_exit(virtio_exit);

MODULE_LICENSE("GPL");
Commit	Line	Data
ec3d41c4 RR	1	#include <linux/virtio.h>
	2	#include <linux/spinlock.h>
	3	#include <linux/virtio_config.h>
	4
b769f579 RR	5	/* Unique numbering for virtio devices. */
	6	static unsigned int dev_index;
	7
ec3d41c4 RR	8	static ssize_t device_show(struct device *_d,
	9	struct device_attribute attr, char buf)
	10	{
	11	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	12	return sprintf(buf, "%hu", dev->id.device);
	13	}
	14	static ssize_t vendor_show(struct device *_d,
	15	struct device_attribute attr, char buf)
	16	{
	17	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	18	return sprintf(buf, "%hu", dev->id.vendor);
	19	}
	20	static ssize_t status_show(struct device *_d,
	21	struct device_attribute attr, char buf)
	22	{
	23	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	24	return sprintf(buf, "0x%08x", dev->config->get_status(dev));
	25	}
b01d9f28 RR	26	static ssize_t modalias_show(struct device *_d,
	27	struct device_attribute attr, char buf)
	28	{
	29	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	30
	31	return sprintf(buf, "virtio:d%08Xv%08X\n",
	32	dev->id.device, dev->id.vendor);
	33	}
a9289282 RR	34	static ssize_t features_show(struct device *_d,
	35	struct device_attribute attr, char buf)
	36	{
	37	struct virtio_device *dev = container_of(_d, struct virtio_device, dev);
	38	unsigned int i;
	39	ssize_t len = 0;
	40
	41	/* We actually represent this as a bitstring, as it could be
	42	* arbitrary length in future. */
	43	for (i = 0; i < ARRAY_SIZE(dev->features)*BITS_PER_LONG; i++)
	44	len += sprintf(buf+len, "%c",
	45	test_bit(i, dev->features) ? '1' : '0');
	46	len += sprintf(buf+len, "\n");
	47	return len;
	48	}
ec3d41c4 RR	49	static struct device_attribute virtio_dev_attrs[] = {
	50	__ATTR_RO(device),
	51	__ATTR_RO(vendor),
	52	__ATTR_RO(status),
b01d9f28	53	__ATTR_RO(modalias),
a9289282	54	__ATTR_RO(features),
ec3d41c4 RR	55	__ATTR_NULL
	56	};
	57
	58	static inline int virtio_id_match(const struct virtio_device *dev,
	59	const struct virtio_device_id *id)
	60	{
e3353853	61	if (id->device != dev->id.device && id->device != VIRTIO_DEV_ANY_ID)
ec3d41c4 RR	62	return 0;
ec3d41c4 RR	63
c89e8016	64	return id->vendor == VIRTIO_DEV_ANY_ID \|\| id->vendor == dev->id.vendor;
ec3d41c4 RR	65	}
	66
	67	/* This looks through all the IDs a driver claims to support. If any of them
	68	* match, we return 1 and the kernel will call virtio_dev_probe(). */
	69	static int virtio_dev_match(struct device _dv, struct device_driver _dr)
	70	{
	71	unsigned int i;
	72	struct virtio_device *dev = container_of(_dv,struct virtio_device,dev);
	73	const struct virtio_device_id *ids;
	74
	75	ids = container_of(_dr, struct virtio_driver, driver)->id_table;
	76	for (i = 0; ids[i].device; i++)
	77	if (virtio_id_match(dev, &ids[i]))
	78	return 1;
	79	return 0;
	80	}
	81
b01d9f28 RR	82	static int virtio_uevent(struct device _dv, struct kobj_uevent_env env)
	83	{
	84	struct virtio_device *dev = container_of(_dv,struct virtio_device,dev);
	85
	86	return add_uevent_var(env, "MODALIAS=virtio:d%08Xv%08X",
	87	dev->id.device, dev->id.vendor);
	88	}
	89
ec3d41c4 RR	90	static void add_status(struct virtio_device *dev, unsigned status)
	91	{
	92	dev->config->set_status(dev, dev->config->get_status(dev) \| status);
	93	}
	94
c45a6816 RR	95	void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
	96	unsigned int fbit)
	97	{
	98	unsigned int i;
	99	struct virtio_driver *drv = container_of(vdev->dev.driver,
	100	struct virtio_driver, driver);
	101
	102	for (i = 0; i < drv->feature_table_size; i++)
	103	if (drv->feature_table[i] == fbit)
	104	return;
	105	BUG();
	106	}
	107	EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature);
	108
ec3d41c4 RR	109	static int virtio_dev_probe(struct device *_d)
ec3d41c4 RR	110	{
c45a6816	111	int err, i;
ec3d41c4 RR	112	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	113	struct virtio_driver *drv = container_of(dev->dev.driver,
	114	struct virtio_driver, driver);
c45a6816	115	u32 device_features;
ec3d41c4	116
c45a6816	117	/* We have a driver! */
ec3d41c4	118	add_status(dev, VIRTIO_CONFIG_S_DRIVER);
c45a6816 RR	119
	120	/* Figure out what features the device supports. */
	121	device_features = dev->config->get_features(dev);
	122
	123	/* Features supported by both device and driver into dev->features. */
	124	memset(dev->features, 0, sizeof(dev->features));
	125	for (i = 0; i < drv->feature_table_size; i++) {
	126	unsigned int f = drv->feature_table[i];
	127	BUG_ON(f >= 32);
	128	if (device_features & (1 << f))
	129	set_bit(f, dev->features);
	130	}
	131
c624896e	132	/* Transport features always preserved to pass to finalize_features. */
dd7c7bc4 RR	133	for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++)
	134	if (device_features & (1 << i))
	135	set_bit(i, dev->features);
	136
ef688e15 RR	137	dev->config->finalize_features(dev);
ef688e15 RR	138
ec3d41c4 RR	139	err = drv->probe(dev);
	140	if (err)
	141	add_status(dev, VIRTIO_CONFIG_S_FAILED);
ef688e15	142	else
b92dea67	143	add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
ef688e15	144
ec3d41c4 RR	145	return err;
	146	}
	147
74b2553f RR	148	static int virtio_dev_remove(struct device *_d)
	149	{
	150	struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
	151	struct virtio_driver *drv = container_of(dev->dev.driver,
	152	struct virtio_driver, driver);
	153
74b2553f	154	drv->remove(dev);
6e5aa7ef RR	155
	156	/* Driver should have reset device. */
	157	BUG_ON(dev->config->get_status(dev));
	158
	159	/* Acknowledge the device's existence again. */
	160	add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
74b2553f RR	161	return 0;
	162	}
	163
e962fa66 MM	164	static struct bus_type virtio_bus = {
	165	.name = "virtio",
	166	.match = virtio_dev_match,
	167	.dev_attrs = virtio_dev_attrs,
	168	.uevent = virtio_uevent,
	169	.probe = virtio_dev_probe,
	170	.remove = virtio_dev_remove,
	171	};
	172
ec3d41c4 RR	173	int register_virtio_driver(struct virtio_driver *driver)
ec3d41c4 RR	174	{
c45a6816 RR	175	/* Catch this early. */
c45a6816 RR	176	BUG_ON(driver->feature_table_size && !driver->feature_table);
ec3d41c4	177	driver->driver.bus = &virtio_bus;
ec3d41c4 RR	178	return driver_register(&driver->driver);
	179	}
	180	EXPORT_SYMBOL_GPL(register_virtio_driver);
	181
	182	void unregister_virtio_driver(struct virtio_driver *driver)
	183	{
	184	driver_unregister(&driver->driver);
	185	}
	186	EXPORT_SYMBOL_GPL(unregister_virtio_driver);
	187
	188	int register_virtio_device(struct virtio_device *dev)
	189	{
	190	int err;
	191
	192	dev->dev.bus = &virtio_bus;
b769f579 RR	193
	194	/* Assign a unique device index and hence name. */
	195	dev->index = dev_index++;
99e0b6c8	196	dev_set_name(&dev->dev, "virtio%u", dev->index);
ec3d41c4	197
6e5aa7ef RR	198	/* We always start by resetting the device, in case a previous
	199	* driver messed it up. This also tests that code path a little. */
	200	dev->config->reset(dev);
	201
ec3d41c4 RR	202	/* Acknowledge that we've seen the device. */
	203	add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
	204
9499f5e7 RR	205	INIT_LIST_HEAD(&dev->vqs);
9499f5e7 RR	206
ec3d41c4 RR	207	/* device_register() causes the bus infrastructure to look for a
	208	* matching driver. */
	209	err = device_register(&dev->dev);
	210	if (err)
	211	add_status(dev, VIRTIO_CONFIG_S_FAILED);
	212	return err;
	213	}
	214	EXPORT_SYMBOL_GPL(register_virtio_device);
	215
	216	void unregister_virtio_device(struct virtio_device *dev)
	217	{
	218	device_unregister(&dev->dev);
	219	}
	220	EXPORT_SYMBOL_GPL(unregister_virtio_device);
	221
ec3d41c4 RR	222	static int virtio_init(void)
	223	{
	224	if (bus_register(&virtio_bus) != 0)
	225	panic("virtio bus registration failed");
	226	return 0;
	227	}
c6fd4701 RR	228
	229	static void __exit virtio_exit(void)
	230	{
	231	bus_unregister(&virtio_bus);
	232	}
ec3d41c4	233	core_initcall(virtio_init);
c6fd4701 RR	234	module_exit(virtio_exit);
	235
	236	MODULE_LICENSE("GPL");