[linux-2.6-block.git] / drivers / usb / mon / mon_main.c

// SPDX-License-Identifier: GPL-2.0
/*
 * The USB Monitor, inspired by Dave Harding's USBMon.
 *
 * mon_main.c: Main file, module initiation and exit, registrations, etc.
 *
 * Copyright (C) 2005 Pete Zaitcev (zaitcev@redhat.com)
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/slab.h>
#include <linux/notifier.h>
#include <linux/mutex.h>

#include "usb_mon.h"


static void mon_stop(struct mon_bus *mbus);
static void mon_dissolve(struct mon_bus *mbus, struct usb_bus *ubus);
static void mon_bus_drop(struct kref *r);
static void mon_bus_init(struct usb_bus *ubus);

DEFINE_MUTEX(mon_lock);

struct mon_bus mon_bus0;		/* Pseudo bus meaning "all buses" */
static LIST_HEAD(mon_buses);		/* All buses we know: struct mon_bus */

/*
 * Link a reader into the bus.
 *
 * This must be called with mon_lock taken because of mbus->ref.
 */
void mon_reader_add(struct mon_bus *mbus, struct mon_reader *r)
{
	unsigned long flags;
	struct list_head *p;

	spin_lock_irqsave(&mbus->lock, flags);
	if (mbus->nreaders == 0) {
		if (mbus == &mon_bus0) {
			list_for_each (p, &mon_buses) {
				struct mon_bus *m1;
				m1 = list_entry(p, struct mon_bus, bus_link);
				m1->u_bus->monitored = 1;
			}
		} else {
			mbus->u_bus->monitored = 1;
		}
	}
	mbus->nreaders++;
	list_add_tail(&r->r_link, &mbus->r_list);
	spin_unlock_irqrestore(&mbus->lock, flags);

	kref_get(&mbus->ref);
}

/*
 * Unlink reader from the bus.
 *
 * This is called with mon_lock taken, so we can decrement mbus->ref.
 */
void mon_reader_del(struct mon_bus *mbus, struct mon_reader *r)
{
	unsigned long flags;

	spin_lock_irqsave(&mbus->lock, flags);
	list_del(&r->r_link);
	--mbus->nreaders;
	if (mbus->nreaders == 0)
		mon_stop(mbus);
	spin_unlock_irqrestore(&mbus->lock, flags);

	kref_put(&mbus->ref, mon_bus_drop);
}

/*
 */
static void mon_bus_submit(struct mon_bus *mbus, struct urb *urb)
{
	unsigned long flags;
	struct mon_reader *r;

	spin_lock_irqsave(&mbus->lock, flags);
	mbus->cnt_events++;
	list_for_each_entry(r, &mbus->r_list, r_link)
		r->rnf_submit(r->r_data, urb);
	spin_unlock_irqrestore(&mbus->lock, flags);
}

static void mon_submit(struct usb_bus *ubus, struct urb *urb)
{
	struct mon_bus *mbus;

	mbus = ubus->mon_bus;
	if (mbus != NULL)
		mon_bus_submit(mbus, urb);
	mon_bus_submit(&mon_bus0, urb);
}

/*
 */
static void mon_bus_submit_error(struct mon_bus *mbus, struct urb *urb, int error)
{
	unsigned long flags;
	struct mon_reader *r;

	spin_lock_irqsave(&mbus->lock, flags);
	mbus->cnt_events++;
	list_for_each_entry(r, &mbus->r_list, r_link)
		r->rnf_error(r->r_data, urb, error);
	spin_unlock_irqrestore(&mbus->lock, flags);
}

static void mon_submit_error(struct usb_bus *ubus, struct urb *urb, int error)
{
	struct mon_bus *mbus;

	mbus = ubus->mon_bus;
	if (mbus != NULL)
		mon_bus_submit_error(mbus, urb, error);
	mon_bus_submit_error(&mon_bus0, urb, error);
}

/*
 */
static void mon_bus_complete(struct mon_bus *mbus, struct urb *urb, int status)
{
	unsigned long flags;
	struct mon_reader *r;

	spin_lock_irqsave(&mbus->lock, flags);
	mbus->cnt_events++;
	list_for_each_entry(r, &mbus->r_list, r_link)
		r->rnf_complete(r->r_data, urb, status);
	spin_unlock_irqrestore(&mbus->lock, flags);
}

static void mon_complete(struct usb_bus *ubus, struct urb *urb, int status)
{
	struct mon_bus *mbus;

	mbus = ubus->mon_bus;
	if (mbus != NULL)
		mon_bus_complete(mbus, urb, status);
	mon_bus_complete(&mon_bus0, urb, status);
}

/* int (*unlink_urb) (struct urb *urb, int status); */

/*
 * Stop monitoring.
 */
static void mon_stop(struct mon_bus *mbus)
{
	struct usb_bus *ubus;

	if (mbus == &mon_bus0) {
		list_for_each_entry(mbus, &mon_buses, bus_link) {
			/*
			 * We do not change nreaders here, so rely on mon_lock.
			 */
			if (mbus->nreaders == 0 && (ubus = mbus->u_bus) != NULL)
				ubus->monitored = 0;
		}
	} else {
		/*
		 * A stop can be called for a dissolved mon_bus in case of
		 * a reader staying across an rmmod foo_hcd, so test ->u_bus.
		 */
		if (mon_bus0.nreaders == 0 && (ubus = mbus->u_bus) != NULL) {
			ubus->monitored = 0;
			mb();
		}
	}
}

/*
 * Add a USB bus (usually by a modprobe foo-hcd)
 *
 * This does not return an error code because the core cannot care less
 * if monitoring is not established.
 */
static void mon_bus_add(struct usb_bus *ubus)
{
	mon_bus_init(ubus);
	mutex_lock(&mon_lock);
	if (mon_bus0.nreaders != 0)
		ubus->monitored = 1;
	mutex_unlock(&mon_lock);
}

/*
 * Remove a USB bus (either from rmmod foo-hcd or from a hot-remove event).
 */
static void mon_bus_remove(struct usb_bus *ubus)
{
	struct mon_bus *mbus = ubus->mon_bus;

	mutex_lock(&mon_lock);
	list_del(&mbus->bus_link);
	if (mbus->text_inited)
		mon_text_del(mbus);
	if (mbus->bin_inited)
		mon_bin_del(mbus);

	mon_dissolve(mbus, ubus);
	kref_put(&mbus->ref, mon_bus_drop);
	mutex_unlock(&mon_lock);
}

static int mon_notify(struct notifier_block *self, unsigned long action,
		      void *dev)
{
	switch (action) {
	case USB_BUS_ADD:
		mon_bus_add(dev);
		break;
	case USB_BUS_REMOVE:
		mon_bus_remove(dev);
	}
	return NOTIFY_OK;
}

static struct notifier_block mon_nb = {
	.notifier_call = 	mon_notify,
};

/*
 * Ops
 */
static const struct usb_mon_operations mon_ops_0 = {
	.urb_submit =	mon_submit,
	.urb_submit_error = mon_submit_error,
	.urb_complete =	mon_complete,
};

/*
 * Tear usb_bus and mon_bus apart.
 */
static void mon_dissolve(struct mon_bus *mbus, struct usb_bus *ubus)
{

	if (ubus->monitored) {
		ubus->monitored = 0;
		mb();
	}

	ubus->mon_bus = NULL;
	mbus->u_bus = NULL;
	mb();

	/* We want synchronize_irq() here, but that needs an argument. */
}

/*
 */
static void mon_bus_drop(struct kref *r)
{
	struct mon_bus *mbus = container_of(r, struct mon_bus, ref);
	kfree(mbus);
}

/*
 * Initialize a bus for us:
 *  - allocate mon_bus
 *  - refcount USB bus struct
 *  - link
 */
static void mon_bus_init(struct usb_bus *ubus)
{
	struct mon_bus *mbus;

	mbus = kzalloc(sizeof(struct mon_bus), GFP_KERNEL);
	if (mbus == NULL)
		goto err_alloc;
	kref_init(&mbus->ref);
	spin_lock_init(&mbus->lock);
	INIT_LIST_HEAD(&mbus->r_list);

	/*
	 * We don't need to take a reference to ubus, because we receive
	 * a notification if the bus is about to be removed.
	 */
	mbus->u_bus = ubus;
	ubus->mon_bus = mbus;

	mbus->text_inited = mon_text_add(mbus, ubus);
	mbus->bin_inited = mon_bin_add(mbus, ubus);

	mutex_lock(&mon_lock);
	list_add_tail(&mbus->bus_link, &mon_buses);
	mutex_unlock(&mon_lock);
	return;

err_alloc:
	return;
}

static void mon_bus0_init(void)
{
	struct mon_bus *mbus = &mon_bus0;

	kref_init(&mbus->ref);
	spin_lock_init(&mbus->lock);
	INIT_LIST_HEAD(&mbus->r_list);

	mbus->text_inited = mon_text_add(mbus, NULL);
	mbus->bin_inited = mon_bin_add(mbus, NULL);
}

/*
 * Search a USB bus by number. Notice that USB bus numbers start from one,
 * which we may later use to identify "all" with zero.
 *
 * This function must be called with mon_lock held.
 *
 * This is obviously inefficient and may be revised in the future.
 */
struct mon_bus *mon_bus_lookup(unsigned int num)
{
	struct mon_bus *mbus;

	if (num == 0) {
		return &mon_bus0;
	}
	list_for_each_entry(mbus, &mon_buses, bus_link) {
		if (mbus->u_bus->busnum == num) {
			return mbus;
		}
	}
	return NULL;
}

static int __init mon_init(void)
{
	struct usb_bus *ubus;
	int rc, id;

	if ((rc = mon_text_init()) != 0)
		goto err_text;
	if ((rc = mon_bin_init()) != 0)
		goto err_bin;

	mon_bus0_init();

	if (usb_mon_register(&mon_ops_0) != 0) {
		printk(KERN_NOTICE TAG ": unable to register with the core\n");
		rc = -ENODEV;
		goto err_reg;
	}
	// MOD_INC_USE_COUNT(which_module?);

	mutex_lock(&usb_bus_idr_lock);
	idr_for_each_entry(&usb_bus_idr, ubus, id)
		mon_bus_init(ubus);
	usb_register_notify(&mon_nb);
	mutex_unlock(&usb_bus_idr_lock);
	return 0;

err_reg:
	mon_bin_exit();
err_bin:
	mon_text_exit();
err_text:
	return rc;
}

static void __exit mon_exit(void)
{
	struct mon_bus *mbus;
	struct list_head *p;

	usb_unregister_notify(&mon_nb);
	usb_mon_deregister();

	mutex_lock(&mon_lock);

	while (!list_empty(&mon_buses)) {
		p = mon_buses.next;
		mbus = list_entry(p, struct mon_bus, bus_link);
		list_del(p);

		if (mbus->text_inited)
			mon_text_del(mbus);
		if (mbus->bin_inited)
			mon_bin_del(mbus);

		/*
		 * This never happens, because the open/close paths in
		 * file level maintain module use counters and so rmmod fails
		 * before reaching here. However, better be safe...
		 */
		if (mbus->nreaders) {
			printk(KERN_ERR TAG
			    ": Outstanding opens (%d) on usb%d, leaking...\n",
			    mbus->nreaders, mbus->u_bus->busnum);
			kref_get(&mbus->ref); /* Force leak */
		}

		mon_dissolve(mbus, mbus->u_bus);
		kref_put(&mbus->ref, mon_bus_drop);
	}

	mbus = &mon_bus0;
	if (mbus->text_inited)
		mon_text_del(mbus);
	if (mbus->bin_inited)
		mon_bin_del(mbus);

	mutex_unlock(&mon_lock);

	mon_text_exit();
	mon_bin_exit();
}

module_init(mon_init);
module_exit(mon_exit);

MODULE_DESCRIPTION("USB Monitor");
MODULE_LICENSE("GPL");
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* The USB Monitor, inspired by Dave Harding's USBMon.
	4	*
	5	* mon_main.c: Main file, module initiation and exit, registrations, etc.
	6	*
	7	* Copyright (C) 2005 Pete Zaitcev (zaitcev@redhat.com)
	8	*/
	9
	10	#include <linux/kernel.h>
	11	#include <linux/module.h>
	12	#include <linux/usb.h>
	13	#include <linux/usb/hcd.h>
	14	#include <linux/slab.h>
	15	#include <linux/notifier.h>
	16	#include <linux/mutex.h>
	17
	18	#include "usb_mon.h"
	19
	20
	21	static void mon_stop(struct mon_bus *mbus);
	22	static void mon_dissolve(struct mon_bus mbus, struct usb_bus ubus);
	23	static void mon_bus_drop(struct kref *r);
	24	static void mon_bus_init(struct usb_bus *ubus);
	25
	26	DEFINE_MUTEX(mon_lock);
	27
	28	struct mon_bus mon_bus0; /* Pseudo bus meaning "all buses" */
	29	static LIST_HEAD(mon_buses); /* All buses we know: struct mon_bus */
	30
	31	/*
	32	* Link a reader into the bus.
	33	*
	34	* This must be called with mon_lock taken because of mbus->ref.
	35	*/
	36	void mon_reader_add(struct mon_bus mbus, struct mon_reader r)
	37	{
	38	unsigned long flags;
	39	struct list_head *p;
	40
	41	spin_lock_irqsave(&mbus->lock, flags);
	42	if (mbus->nreaders == 0) {
	43	if (mbus == &mon_bus0) {
	44	list_for_each (p, &mon_buses) {
	45	struct mon_bus *m1;
	46	m1 = list_entry(p, struct mon_bus, bus_link);
	47	m1->u_bus->monitored = 1;
	48	}
	49	} else {
	50	mbus->u_bus->monitored = 1;
	51	}
	52	}
	53	mbus->nreaders++;
	54	list_add_tail(&r->r_link, &mbus->r_list);
	55	spin_unlock_irqrestore(&mbus->lock, flags);
	56
	57	kref_get(&mbus->ref);
	58	}
	59
	60	/*
	61	* Unlink reader from the bus.
	62	*
	63	* This is called with mon_lock taken, so we can decrement mbus->ref.
	64	*/
	65	void mon_reader_del(struct mon_bus mbus, struct mon_reader r)
	66	{
	67	unsigned long flags;
	68
	69	spin_lock_irqsave(&mbus->lock, flags);
	70	list_del(&r->r_link);
	71	--mbus->nreaders;
	72	if (mbus->nreaders == 0)
	73	mon_stop(mbus);
	74	spin_unlock_irqrestore(&mbus->lock, flags);
	75
	76	kref_put(&mbus->ref, mon_bus_drop);
	77	}
	78
	79	/*
	80	*/
	81	static void mon_bus_submit(struct mon_bus mbus, struct urb urb)
	82	{
	83	unsigned long flags;
	84	struct mon_reader *r;
	85
	86	spin_lock_irqsave(&mbus->lock, flags);
	87	mbus->cnt_events++;
	88	list_for_each_entry(r, &mbus->r_list, r_link)
	89	r->rnf_submit(r->r_data, urb);
	90	spin_unlock_irqrestore(&mbus->lock, flags);
	91	}
	92
	93	static void mon_submit(struct usb_bus ubus, struct urb urb)
	94	{
	95	struct mon_bus *mbus;
	96
	97	mbus = ubus->mon_bus;
	98	if (mbus != NULL)
	99	mon_bus_submit(mbus, urb);
	100	mon_bus_submit(&mon_bus0, urb);
	101	}
	102
	103	/*
	104	*/
	105	static void mon_bus_submit_error(struct mon_bus mbus, struct urb urb, int error)
	106	{
	107	unsigned long flags;
	108	struct mon_reader *r;
	109
	110	spin_lock_irqsave(&mbus->lock, flags);
	111	mbus->cnt_events++;
	112	list_for_each_entry(r, &mbus->r_list, r_link)
	113	r->rnf_error(r->r_data, urb, error);
	114	spin_unlock_irqrestore(&mbus->lock, flags);
	115	}
	116
	117	static void mon_submit_error(struct usb_bus ubus, struct urb urb, int error)
	118	{
	119	struct mon_bus *mbus;
	120
	121	mbus = ubus->mon_bus;
	122	if (mbus != NULL)
	123	mon_bus_submit_error(mbus, urb, error);
	124	mon_bus_submit_error(&mon_bus0, urb, error);
	125	}
	126
	127	/*
	128	*/
	129	static void mon_bus_complete(struct mon_bus mbus, struct urb urb, int status)
	130	{
	131	unsigned long flags;
	132	struct mon_reader *r;
	133
	134	spin_lock_irqsave(&mbus->lock, flags);
	135	mbus->cnt_events++;
	136	list_for_each_entry(r, &mbus->r_list, r_link)
	137	r->rnf_complete(r->r_data, urb, status);
	138	spin_unlock_irqrestore(&mbus->lock, flags);
	139	}
	140
	141	static void mon_complete(struct usb_bus ubus, struct urb urb, int status)
	142	{
	143	struct mon_bus *mbus;
	144
	145	mbus = ubus->mon_bus;
	146	if (mbus != NULL)
	147	mon_bus_complete(mbus, urb, status);
	148	mon_bus_complete(&mon_bus0, urb, status);
	149	}
	150
	151	/* int (unlink_urb) (struct urb urb, int status); */
	152
	153	/*
	154	* Stop monitoring.
	155	*/
	156	static void mon_stop(struct mon_bus *mbus)
	157	{
	158	struct usb_bus *ubus;
	159
	160	if (mbus == &mon_bus0) {
	161	list_for_each_entry(mbus, &mon_buses, bus_link) {
	162	/*
	163	* We do not change nreaders here, so rely on mon_lock.
	164	*/
	165	if (mbus->nreaders == 0 && (ubus = mbus->u_bus) != NULL)
	166	ubus->monitored = 0;
	167	}
	168	} else {
	169	/*
	170	* A stop can be called for a dissolved mon_bus in case of
	171	* a reader staying across an rmmod foo_hcd, so test ->u_bus.
	172	*/
	173	if (mon_bus0.nreaders == 0 && (ubus = mbus->u_bus) != NULL) {
	174	ubus->monitored = 0;
	175	mb();
	176	}
	177	}
	178	}
	179
	180	/*
	181	* Add a USB bus (usually by a modprobe foo-hcd)
	182	*
	183	* This does not return an error code because the core cannot care less
	184	* if monitoring is not established.
	185	*/
	186	static void mon_bus_add(struct usb_bus *ubus)
	187	{
	188	mon_bus_init(ubus);
	189	mutex_lock(&mon_lock);
	190	if (mon_bus0.nreaders != 0)
	191	ubus->monitored = 1;
	192	mutex_unlock(&mon_lock);
	193	}
	194
	195	/*
	196	* Remove a USB bus (either from rmmod foo-hcd or from a hot-remove event).
	197	*/
	198	static void mon_bus_remove(struct usb_bus *ubus)
	199	{
	200	struct mon_bus *mbus = ubus->mon_bus;
	201
	202	mutex_lock(&mon_lock);
	203	list_del(&mbus->bus_link);
	204	if (mbus->text_inited)
	205	mon_text_del(mbus);
	206	if (mbus->bin_inited)
	207	mon_bin_del(mbus);
	208
	209	mon_dissolve(mbus, ubus);
	210	kref_put(&mbus->ref, mon_bus_drop);
	211	mutex_unlock(&mon_lock);
	212	}
	213
	214	static int mon_notify(struct notifier_block *self, unsigned long action,
	215	void *dev)
	216	{
	217	switch (action) {
	218	case USB_BUS_ADD:
	219	mon_bus_add(dev);
	220	break;
	221	case USB_BUS_REMOVE:
	222	mon_bus_remove(dev);
	223	}
	224	return NOTIFY_OK;
	225	}
	226
	227	static struct notifier_block mon_nb = {
	228	.notifier_call = mon_notify,
	229	};
	230
	231	/*
	232	* Ops
	233	*/
	234	static const struct usb_mon_operations mon_ops_0 = {
	235	.urb_submit = mon_submit,
	236	.urb_submit_error = mon_submit_error,
	237	.urb_complete = mon_complete,
	238	};
	239
	240	/*
	241	* Tear usb_bus and mon_bus apart.
	242	*/
	243	static void mon_dissolve(struct mon_bus mbus, struct usb_bus ubus)
	244	{
	245
	246	if (ubus->monitored) {
	247	ubus->monitored = 0;
	248	mb();
	249	}
	250
	251	ubus->mon_bus = NULL;
	252	mbus->u_bus = NULL;
	253	mb();
	254
	255	/* We want synchronize_irq() here, but that needs an argument. */
	256	}
	257
	258	/*
	259	*/
	260	static void mon_bus_drop(struct kref *r)
	261	{
	262	struct mon_bus *mbus = container_of(r, struct mon_bus, ref);
	263	kfree(mbus);
	264	}
	265
	266	/*
	267	* Initialize a bus for us:
	268	* - allocate mon_bus
	269	* - refcount USB bus struct
	270	* - link
	271	*/
	272	static void mon_bus_init(struct usb_bus *ubus)
	273	{
	274	struct mon_bus *mbus;
	275
	276	mbus = kzalloc(sizeof(struct mon_bus), GFP_KERNEL);
	277	if (mbus == NULL)
	278	goto err_alloc;
	279	kref_init(&mbus->ref);
	280	spin_lock_init(&mbus->lock);
	281	INIT_LIST_HEAD(&mbus->r_list);
	282
	283	/*
	284	* We don't need to take a reference to ubus, because we receive
	285	* a notification if the bus is about to be removed.
	286	*/
	287	mbus->u_bus = ubus;
	288	ubus->mon_bus = mbus;
	289
	290	mbus->text_inited = mon_text_add(mbus, ubus);
	291	mbus->bin_inited = mon_bin_add(mbus, ubus);
	292
	293	mutex_lock(&mon_lock);
	294	list_add_tail(&mbus->bus_link, &mon_buses);
	295	mutex_unlock(&mon_lock);
	296	return;
	297
	298	err_alloc:
	299	return;
	300	}
	301
	302	static void mon_bus0_init(void)
	303	{
	304	struct mon_bus *mbus = &mon_bus0;
	305
	306	kref_init(&mbus->ref);
	307	spin_lock_init(&mbus->lock);
	308	INIT_LIST_HEAD(&mbus->r_list);
	309
	310	mbus->text_inited = mon_text_add(mbus, NULL);
	311	mbus->bin_inited = mon_bin_add(mbus, NULL);
	312	}
	313
	314	/*
	315	* Search a USB bus by number. Notice that USB bus numbers start from one,
	316	* which we may later use to identify "all" with zero.
	317	*
	318	* This function must be called with mon_lock held.
	319	*
	320	* This is obviously inefficient and may be revised in the future.
	321	*/
	322	struct mon_bus *mon_bus_lookup(unsigned int num)
	323	{
	324	struct mon_bus *mbus;
	325
	326	if (num == 0) {
	327	return &mon_bus0;
	328	}
	329	list_for_each_entry(mbus, &mon_buses, bus_link) {
	330	if (mbus->u_bus->busnum == num) {
	331	return mbus;
	332	}
	333	}
	334	return NULL;
	335	}
	336
	337	static int __init mon_init(void)
	338	{
	339	struct usb_bus *ubus;
	340	int rc, id;
	341
	342	if ((rc = mon_text_init()) != 0)
	343	goto err_text;
	344	if ((rc = mon_bin_init()) != 0)
	345	goto err_bin;
	346
	347	mon_bus0_init();
	348
	349	if (usb_mon_register(&mon_ops_0) != 0) {
	350	printk(KERN_NOTICE TAG ": unable to register with the core\n");
	351	rc = -ENODEV;
	352	goto err_reg;
	353	}
	354	// MOD_INC_USE_COUNT(which_module?);
	355
	356	mutex_lock(&usb_bus_idr_lock);
	357	idr_for_each_entry(&usb_bus_idr, ubus, id)
	358	mon_bus_init(ubus);
	359	usb_register_notify(&mon_nb);
	360	mutex_unlock(&usb_bus_idr_lock);
	361	return 0;
	362
	363	err_reg:
	364	mon_bin_exit();
	365	err_bin:
	366	mon_text_exit();
	367	err_text:
	368	return rc;
	369	}
	370
	371	static void __exit mon_exit(void)
	372	{
	373	struct mon_bus *mbus;
	374	struct list_head *p;
	375
	376	usb_unregister_notify(&mon_nb);
	377	usb_mon_deregister();
	378
	379	mutex_lock(&mon_lock);
	380
	381	while (!list_empty(&mon_buses)) {
	382	p = mon_buses.next;
	383	mbus = list_entry(p, struct mon_bus, bus_link);
	384	list_del(p);
	385
	386	if (mbus->text_inited)
	387	mon_text_del(mbus);
	388	if (mbus->bin_inited)
	389	mon_bin_del(mbus);
	390
	391	/*
	392	* This never happens, because the open/close paths in
	393	* file level maintain module use counters and so rmmod fails
	394	* before reaching here. However, better be safe...
	395	*/
	396	if (mbus->nreaders) {
	397	printk(KERN_ERR TAG
	398	": Outstanding opens (%d) on usb%d, leaking...\n",
	399	mbus->nreaders, mbus->u_bus->busnum);
	400	kref_get(&mbus->ref); /* Force leak */
	401	}
	402
	403	mon_dissolve(mbus, mbus->u_bus);
	404	kref_put(&mbus->ref, mon_bus_drop);
	405	}
	406
	407	mbus = &mon_bus0;
	408	if (mbus->text_inited)
	409	mon_text_del(mbus);
	410	if (mbus->bin_inited)
	411	mon_bin_del(mbus);
	412
	413	mutex_unlock(&mon_lock);
	414
	415	mon_text_exit();
	416	mon_bin_exit();
	417	}
	418
	419	module_init(mon_init);
	420	module_exit(mon_exit);
	421
	422	MODULE_DESCRIPTION("USB Monitor");
	423	MODULE_LICENSE("GPL");