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v6.8
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
  4 */
  5
  6#include <linux/device.h>
  7#include <linux/file.h>
  8#include <linux/kthread.h>
  9#include <linux/module.h>
 10
 11#include "usbip_common.h"
 12#include "stub.h"
 13
 14/*
 15 * usbip_status shows the status of usbip-host as long as this driver is bound
 16 * to the target device.
 17 */
 18static ssize_t usbip_status_show(struct device *dev,
 19				 struct device_attribute *attr, char *buf)
 20{
 21	struct stub_device *sdev = dev_get_drvdata(dev);
 22	int status;
 23
 24	if (!sdev) {
 25		dev_err(dev, "sdev is null\n");
 26		return -ENODEV;
 27	}
 28
 29	spin_lock_irq(&sdev->ud.lock);
 30	status = sdev->ud.status;
 31	spin_unlock_irq(&sdev->ud.lock);
 32
 33	return sysfs_emit(buf, "%d\n", status);
 34}
 35static DEVICE_ATTR_RO(usbip_status);
 36
 37/*
 38 * usbip_sockfd gets a socket descriptor of an established TCP connection that
 39 * is used to transfer usbip requests by kernel threads. -1 is a magic number
 40 * by which usbip connection is finished.
 41 */
 42static ssize_t usbip_sockfd_store(struct device *dev, struct device_attribute *attr,
 43			    const char *buf, size_t count)
 44{
 45	struct stub_device *sdev = dev_get_drvdata(dev);
 46	int sockfd = 0;
 47	struct socket *socket;
 48	int rv;
 49	struct task_struct *tcp_rx = NULL;
 50	struct task_struct *tcp_tx = NULL;
 51
 52	if (!sdev) {
 53		dev_err(dev, "sdev is null\n");
 54		return -ENODEV;
 55	}
 56
 57	rv = sscanf(buf, "%d", &sockfd);
 58	if (rv != 1)
 59		return -EINVAL;
 60
 61	if (sockfd != -1) {
 62		int err;
 63
 64		dev_info(dev, "stub up\n");
 65
 66		mutex_lock(&sdev->ud.sysfs_lock);
 67		spin_lock_irq(&sdev->ud.lock);
 68
 69		if (sdev->ud.status != SDEV_ST_AVAILABLE) {
 70			dev_err(dev, "not ready\n");
 71			goto err;
 72		}
 73
 74		socket = sockfd_lookup(sockfd, &err);
 75		if (!socket) {
 76			dev_err(dev, "failed to lookup sock");
 77			goto err;
 78		}
 79
 80		if (socket->type != SOCK_STREAM) {
 81			dev_err(dev, "Expecting SOCK_STREAM - found %d",
 82				socket->type);
 83			goto sock_err;
 84		}
 85
 86		/* unlock and create threads and get tasks */
 87		spin_unlock_irq(&sdev->ud.lock);
 88		tcp_rx = kthread_create(stub_rx_loop, &sdev->ud, "stub_rx");
 89		if (IS_ERR(tcp_rx)) {
 90			sockfd_put(socket);
 91			goto unlock_mutex;
 92		}
 93		tcp_tx = kthread_create(stub_tx_loop, &sdev->ud, "stub_tx");
 94		if (IS_ERR(tcp_tx)) {
 95			kthread_stop(tcp_rx);
 96			sockfd_put(socket);
 97			goto unlock_mutex;
 98		}
 99
100		/* get task structs now */
101		get_task_struct(tcp_rx);
102		get_task_struct(tcp_tx);
 
103
104		/* lock and update sdev->ud state */
105		spin_lock_irq(&sdev->ud.lock);
106		sdev->ud.tcp_socket = socket;
107		sdev->ud.sockfd = sockfd;
108		sdev->ud.tcp_rx = tcp_rx;
109		sdev->ud.tcp_tx = tcp_tx;
110		sdev->ud.status = SDEV_ST_USED;
111		spin_unlock_irq(&sdev->ud.lock);
112
113		wake_up_process(sdev->ud.tcp_rx);
114		wake_up_process(sdev->ud.tcp_tx);
115
116		mutex_unlock(&sdev->ud.sysfs_lock);
117
118	} else {
119		dev_info(dev, "stub down\n");
120
121		mutex_lock(&sdev->ud.sysfs_lock);
122
123		spin_lock_irq(&sdev->ud.lock);
124		if (sdev->ud.status != SDEV_ST_USED)
125			goto err;
126
127		spin_unlock_irq(&sdev->ud.lock);
128
129		usbip_event_add(&sdev->ud, SDEV_EVENT_DOWN);
130		mutex_unlock(&sdev->ud.sysfs_lock);
131	}
132
133	return count;
134
135sock_err:
136	sockfd_put(socket);
137err:
138	spin_unlock_irq(&sdev->ud.lock);
139unlock_mutex:
140	mutex_unlock(&sdev->ud.sysfs_lock);
141	return -EINVAL;
142}
143static DEVICE_ATTR_WO(usbip_sockfd);
144
145static struct attribute *usbip_attrs[] = {
146	&dev_attr_usbip_status.attr,
147	&dev_attr_usbip_sockfd.attr,
148	&dev_attr_usbip_debug.attr,
149	NULL,
150};
151ATTRIBUTE_GROUPS(usbip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
152
153static void stub_shutdown_connection(struct usbip_device *ud)
154{
155	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
156
157	/*
158	 * When removing an exported device, kernel panic sometimes occurred
159	 * and then EIP was sk_wait_data of stub_rx thread. Is this because
160	 * sk_wait_data returned though stub_rx thread was already finished by
161	 * step 1?
162	 */
163	if (ud->tcp_socket) {
164		dev_dbg(&sdev->udev->dev, "shutdown sockfd %d\n", ud->sockfd);
165		kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
166	}
167
168	/* 1. stop threads */
169	if (ud->tcp_rx) {
170		kthread_stop_put(ud->tcp_rx);
171		ud->tcp_rx = NULL;
172	}
173	if (ud->tcp_tx) {
174		kthread_stop_put(ud->tcp_tx);
175		ud->tcp_tx = NULL;
176	}
177
178	/*
179	 * 2. close the socket
180	 *
181	 * tcp_socket is freed after threads are killed so that usbip_xmit does
182	 * not touch NULL socket.
183	 */
184	if (ud->tcp_socket) {
185		sockfd_put(ud->tcp_socket);
186		ud->tcp_socket = NULL;
187		ud->sockfd = -1;
188	}
189
190	/* 3. free used data */
191	stub_device_cleanup_urbs(sdev);
192
193	/* 4. free stub_unlink */
194	{
195		unsigned long flags;
196		struct stub_unlink *unlink, *tmp;
197
198		spin_lock_irqsave(&sdev->priv_lock, flags);
199		list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
200			list_del(&unlink->list);
201			kfree(unlink);
202		}
203		list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free,
204					 list) {
205			list_del(&unlink->list);
206			kfree(unlink);
207		}
208		spin_unlock_irqrestore(&sdev->priv_lock, flags);
209	}
210}
211
212static void stub_device_reset(struct usbip_device *ud)
213{
214	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
215	struct usb_device *udev = sdev->udev;
216	int ret;
217
218	dev_dbg(&udev->dev, "device reset");
219
220	ret = usb_lock_device_for_reset(udev, NULL);
221	if (ret < 0) {
222		dev_err(&udev->dev, "lock for reset\n");
223		spin_lock_irq(&ud->lock);
224		ud->status = SDEV_ST_ERROR;
225		spin_unlock_irq(&ud->lock);
226		return;
227	}
228
229	/* try to reset the device */
230	ret = usb_reset_device(udev);
231	usb_unlock_device(udev);
232
233	spin_lock_irq(&ud->lock);
234	if (ret) {
235		dev_err(&udev->dev, "device reset\n");
236		ud->status = SDEV_ST_ERROR;
237	} else {
238		dev_info(&udev->dev, "device reset\n");
239		ud->status = SDEV_ST_AVAILABLE;
240	}
241	spin_unlock_irq(&ud->lock);
242}
243
244static void stub_device_unusable(struct usbip_device *ud)
245{
246	spin_lock_irq(&ud->lock);
247	ud->status = SDEV_ST_ERROR;
248	spin_unlock_irq(&ud->lock);
249}
250
251/**
252 * stub_device_alloc - allocate a new stub_device struct
253 * @udev: usb_device of a new device
254 *
255 * Allocates and initializes a new stub_device struct.
256 */
257static struct stub_device *stub_device_alloc(struct usb_device *udev)
258{
259	struct stub_device *sdev;
260	int busnum = udev->bus->busnum;
261	int devnum = udev->devnum;
262
263	dev_dbg(&udev->dev, "allocating stub device");
264
265	/* yes, it's a new device */
266	sdev = kzalloc(sizeof(struct stub_device), GFP_KERNEL);
267	if (!sdev)
268		return NULL;
269
270	sdev->udev = usb_get_dev(udev);
271
272	/*
273	 * devid is defined with devnum when this driver is first allocated.
274	 * devnum may change later if a device is reset. However, devid never
275	 * changes during a usbip connection.
276	 */
277	sdev->devid		= (busnum << 16) | devnum;
278	sdev->ud.side		= USBIP_STUB;
279	sdev->ud.status		= SDEV_ST_AVAILABLE;
280	spin_lock_init(&sdev->ud.lock);
281	mutex_init(&sdev->ud.sysfs_lock);
282	sdev->ud.tcp_socket	= NULL;
283	sdev->ud.sockfd		= -1;
284
285	INIT_LIST_HEAD(&sdev->priv_init);
286	INIT_LIST_HEAD(&sdev->priv_tx);
287	INIT_LIST_HEAD(&sdev->priv_free);
288	INIT_LIST_HEAD(&sdev->unlink_free);
289	INIT_LIST_HEAD(&sdev->unlink_tx);
290	spin_lock_init(&sdev->priv_lock);
291
292	init_waitqueue_head(&sdev->tx_waitq);
293
294	sdev->ud.eh_ops.shutdown = stub_shutdown_connection;
295	sdev->ud.eh_ops.reset    = stub_device_reset;
296	sdev->ud.eh_ops.unusable = stub_device_unusable;
297
298	usbip_start_eh(&sdev->ud);
299
300	dev_dbg(&udev->dev, "register new device\n");
301
302	return sdev;
303}
304
305static void stub_device_free(struct stub_device *sdev)
306{
307	kfree(sdev);
308}
309
310static int stub_probe(struct usb_device *udev)
311{
312	struct stub_device *sdev = NULL;
313	const char *udev_busid = dev_name(&udev->dev);
314	struct bus_id_priv *busid_priv;
315	int rc = 0;
316	char save_status;
317
318	dev_dbg(&udev->dev, "Enter probe\n");
319
320	/* Not sure if this is our device. Allocate here to avoid
321	 * calling alloc while holding busid_table lock.
322	 */
323	sdev = stub_device_alloc(udev);
324	if (!sdev)
325		return -ENOMEM;
326
327	/* check we should claim or not by busid_table */
328	busid_priv = get_busid_priv(udev_busid);
329	if (!busid_priv || (busid_priv->status == STUB_BUSID_REMOV) ||
330	    (busid_priv->status == STUB_BUSID_OTHER)) {
331		dev_info(&udev->dev,
332			"%s is not in match_busid table... skip!\n",
333			udev_busid);
334
335		/*
336		 * Return value should be ENODEV or ENOXIO to continue trying
337		 * other matched drivers by the driver core.
338		 * See driver_probe_device() in driver/base/dd.c
339		 */
340		rc = -ENODEV;
341		if (!busid_priv)
342			goto sdev_free;
343
344		goto call_put_busid_priv;
345	}
346
347	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB) {
348		dev_dbg(&udev->dev, "%s is a usb hub device... skip!\n",
349			 udev_busid);
350		rc = -ENODEV;
351		goto call_put_busid_priv;
352	}
353
354	if (!strcmp(udev->bus->bus_name, "vhci_hcd")) {
355		dev_dbg(&udev->dev,
356			"%s is attached on vhci_hcd... skip!\n",
357			udev_busid);
358
359		rc = -ENODEV;
360		goto call_put_busid_priv;
361	}
362
 
 
 
 
 
 
363
364	dev_info(&udev->dev,
365		"usbip-host: register new device (bus %u dev %u)\n",
366		udev->bus->busnum, udev->devnum);
367
368	busid_priv->shutdown_busid = 0;
369
370	/* set private data to usb_device */
371	dev_set_drvdata(&udev->dev, sdev);
372
373	busid_priv->sdev = sdev;
374	busid_priv->udev = udev;
375
376	save_status = busid_priv->status;
377	busid_priv->status = STUB_BUSID_ALLOC;
378
379	/* release the busid_lock */
380	put_busid_priv(busid_priv);
381
382	/*
383	 * Claim this hub port.
384	 * It doesn't matter what value we pass as owner
385	 * (struct dev_state) as long as it is unique.
386	 */
387	rc = usb_hub_claim_port(udev->parent, udev->portnum,
388			(struct usb_dev_state *) udev);
389	if (rc) {
390		dev_dbg(&udev->dev, "unable to claim port\n");
391		goto err_port;
392	}
393
394	return 0;
 
 
 
 
 
 
 
 
395
 
 
 
396err_port:
397	dev_set_drvdata(&udev->dev, NULL);
 
398
399	/* we already have busid_priv, just lock busid_lock */
400	spin_lock(&busid_priv->busid_lock);
401	busid_priv->sdev = NULL;
402	busid_priv->status = save_status;
403	spin_unlock(&busid_priv->busid_lock);
404	/* lock is released - go to free */
405	goto sdev_free;
406
407call_put_busid_priv:
408	/* release the busid_lock */
409	put_busid_priv(busid_priv);
410
411sdev_free:
412	usb_put_dev(udev);
413	stub_device_free(sdev);
414
415	return rc;
416}
417
418static void shutdown_busid(struct bus_id_priv *busid_priv)
419{
420	usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
 
 
421
422	/* wait for the stop of the event handler */
423	usbip_stop_eh(&busid_priv->sdev->ud);
 
424}
425
426/*
427 * called in usb_disconnect() or usb_deregister()
428 * but only if actconfig(active configuration) exists
429 */
430static void stub_disconnect(struct usb_device *udev)
431{
432	struct stub_device *sdev;
433	const char *udev_busid = dev_name(&udev->dev);
434	struct bus_id_priv *busid_priv;
435	int rc;
436
437	dev_dbg(&udev->dev, "Enter disconnect\n");
438
439	busid_priv = get_busid_priv(udev_busid);
440	if (!busid_priv) {
441		BUG();
442		return;
443	}
444
445	sdev = dev_get_drvdata(&udev->dev);
446
447	/* get stub_device */
448	if (!sdev) {
449		dev_err(&udev->dev, "could not get device");
450		/* release busid_lock */
451		put_busid_priv(busid_priv);
452		return;
453	}
454
455	dev_set_drvdata(&udev->dev, NULL);
456
457	/* release busid_lock before call to remove device files */
458	put_busid_priv(busid_priv);
459
460	/*
461	 * NOTE: rx/tx threads are invoked for each usb_device.
462	 */
 
463
464	/* release port */
465	rc = usb_hub_release_port(udev->parent, udev->portnum,
466				  (struct usb_dev_state *) udev);
467	/*
468	 * NOTE: If a HUB disconnect triggered disconnect of the down stream
469	 * device usb_hub_release_port will return -ENODEV so we can safely ignore
470	 * that error here.
471	 */
472	if (rc && (rc != -ENODEV)) {
473		dev_dbg(&udev->dev, "unable to release port (%i)\n", rc);
474		return;
475	}
476
477	/* If usb reset is called from event handler */
478	if (usbip_in_eh(current))
479		return;
480
481	/* we already have busid_priv, just lock busid_lock */
482	spin_lock(&busid_priv->busid_lock);
483	if (!busid_priv->shutdown_busid)
484		busid_priv->shutdown_busid = 1;
485	/* release busid_lock */
486	spin_unlock(&busid_priv->busid_lock);
487
488	/* shutdown the current connection */
489	shutdown_busid(busid_priv);
490
491	usb_put_dev(sdev->udev);
492
493	/* we already have busid_priv, just lock busid_lock */
494	spin_lock(&busid_priv->busid_lock);
495	/* free sdev */
496	busid_priv->sdev = NULL;
497	stub_device_free(sdev);
498
499	if (busid_priv->status == STUB_BUSID_ALLOC)
500		busid_priv->status = STUB_BUSID_ADDED;
501	/* release busid_lock */
502	spin_unlock(&busid_priv->busid_lock);
503	return;
504}
505
506#ifdef CONFIG_PM
507
508/* These functions need usb_port_suspend and usb_port_resume,
509 * which reside in drivers/usb/core/usb.h. Skip for now. */
510
511static int stub_suspend(struct usb_device *udev, pm_message_t message)
512{
513	dev_dbg(&udev->dev, "stub_suspend\n");
514
515	return 0;
516}
517
518static int stub_resume(struct usb_device *udev, pm_message_t message)
519{
520	dev_dbg(&udev->dev, "stub_resume\n");
521
522	return 0;
523}
524
525#endif	/* CONFIG_PM */
526
527struct usb_device_driver stub_driver = {
528	.name		= "usbip-host",
529	.probe		= stub_probe,
530	.disconnect	= stub_disconnect,
531#ifdef CONFIG_PM
532	.suspend	= stub_suspend,
533	.resume		= stub_resume,
534#endif
535	.supports_autosuspend	=	0,
536	.dev_groups	= usbip_groups,
537};
v4.17
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
  4 */
  5
  6#include <linux/device.h>
  7#include <linux/file.h>
  8#include <linux/kthread.h>
  9#include <linux/module.h>
 10
 11#include "usbip_common.h"
 12#include "stub.h"
 13
 14/*
 15 * usbip_status shows the status of usbip-host as long as this driver is bound
 16 * to the target device.
 17 */
 18static ssize_t usbip_status_show(struct device *dev,
 19				 struct device_attribute *attr, char *buf)
 20{
 21	struct stub_device *sdev = dev_get_drvdata(dev);
 22	int status;
 23
 24	if (!sdev) {
 25		dev_err(dev, "sdev is null\n");
 26		return -ENODEV;
 27	}
 28
 29	spin_lock_irq(&sdev->ud.lock);
 30	status = sdev->ud.status;
 31	spin_unlock_irq(&sdev->ud.lock);
 32
 33	return snprintf(buf, PAGE_SIZE, "%d\n", status);
 34}
 35static DEVICE_ATTR_RO(usbip_status);
 36
 37/*
 38 * usbip_sockfd gets a socket descriptor of an established TCP connection that
 39 * is used to transfer usbip requests by kernel threads. -1 is a magic number
 40 * by which usbip connection is finished.
 41 */
 42static ssize_t usbip_sockfd_store(struct device *dev, struct device_attribute *attr,
 43			    const char *buf, size_t count)
 44{
 45	struct stub_device *sdev = dev_get_drvdata(dev);
 46	int sockfd = 0;
 47	struct socket *socket;
 48	int rv;
 
 
 49
 50	if (!sdev) {
 51		dev_err(dev, "sdev is null\n");
 52		return -ENODEV;
 53	}
 54
 55	rv = sscanf(buf, "%d", &sockfd);
 56	if (rv != 1)
 57		return -EINVAL;
 58
 59	if (sockfd != -1) {
 60		int err;
 61
 62		dev_info(dev, "stub up\n");
 63
 
 64		spin_lock_irq(&sdev->ud.lock);
 65
 66		if (sdev->ud.status != SDEV_ST_AVAILABLE) {
 67			dev_err(dev, "not ready\n");
 68			goto err;
 69		}
 70
 71		socket = sockfd_lookup(sockfd, &err);
 72		if (!socket)
 
 73			goto err;
 
 74
 75		sdev->ud.tcp_socket = socket;
 76		sdev->ud.sockfd = sockfd;
 
 
 
 77
 
 78		spin_unlock_irq(&sdev->ud.lock);
 
 
 
 
 
 
 
 
 
 
 
 79
 80		sdev->ud.tcp_rx = kthread_get_run(stub_rx_loop, &sdev->ud,
 81						  "stub_rx");
 82		sdev->ud.tcp_tx = kthread_get_run(stub_tx_loop, &sdev->ud,
 83						  "stub_tx");
 84
 
 85		spin_lock_irq(&sdev->ud.lock);
 
 
 
 
 86		sdev->ud.status = SDEV_ST_USED;
 87		spin_unlock_irq(&sdev->ud.lock);
 88
 
 
 
 
 
 89	} else {
 90		dev_info(dev, "stub down\n");
 91
 
 
 92		spin_lock_irq(&sdev->ud.lock);
 93		if (sdev->ud.status != SDEV_ST_USED)
 94			goto err;
 95
 96		spin_unlock_irq(&sdev->ud.lock);
 97
 98		usbip_event_add(&sdev->ud, SDEV_EVENT_DOWN);
 
 99	}
100
101	return count;
102
 
 
103err:
104	spin_unlock_irq(&sdev->ud.lock);
 
 
105	return -EINVAL;
106}
107static DEVICE_ATTR_WO(usbip_sockfd);
108
109static int stub_add_files(struct device *dev)
110{
111	int err = 0;
112
113	err = device_create_file(dev, &dev_attr_usbip_status);
114	if (err)
115		goto err_status;
116
117	err = device_create_file(dev, &dev_attr_usbip_sockfd);
118	if (err)
119		goto err_sockfd;
120
121	err = device_create_file(dev, &dev_attr_usbip_debug);
122	if (err)
123		goto err_debug;
124
125	return 0;
126
127err_debug:
128	device_remove_file(dev, &dev_attr_usbip_sockfd);
129err_sockfd:
130	device_remove_file(dev, &dev_attr_usbip_status);
131err_status:
132	return err;
133}
134
135static void stub_remove_files(struct device *dev)
136{
137	device_remove_file(dev, &dev_attr_usbip_status);
138	device_remove_file(dev, &dev_attr_usbip_sockfd);
139	device_remove_file(dev, &dev_attr_usbip_debug);
140}
141
142static void stub_shutdown_connection(struct usbip_device *ud)
143{
144	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
145
146	/*
147	 * When removing an exported device, kernel panic sometimes occurred
148	 * and then EIP was sk_wait_data of stub_rx thread. Is this because
149	 * sk_wait_data returned though stub_rx thread was already finished by
150	 * step 1?
151	 */
152	if (ud->tcp_socket) {
153		dev_dbg(&sdev->udev->dev, "shutdown sockfd %d\n", ud->sockfd);
154		kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
155	}
156
157	/* 1. stop threads */
158	if (ud->tcp_rx) {
159		kthread_stop_put(ud->tcp_rx);
160		ud->tcp_rx = NULL;
161	}
162	if (ud->tcp_tx) {
163		kthread_stop_put(ud->tcp_tx);
164		ud->tcp_tx = NULL;
165	}
166
167	/*
168	 * 2. close the socket
169	 *
170	 * tcp_socket is freed after threads are killed so that usbip_xmit does
171	 * not touch NULL socket.
172	 */
173	if (ud->tcp_socket) {
174		sockfd_put(ud->tcp_socket);
175		ud->tcp_socket = NULL;
176		ud->sockfd = -1;
177	}
178
179	/* 3. free used data */
180	stub_device_cleanup_urbs(sdev);
181
182	/* 4. free stub_unlink */
183	{
184		unsigned long flags;
185		struct stub_unlink *unlink, *tmp;
186
187		spin_lock_irqsave(&sdev->priv_lock, flags);
188		list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
189			list_del(&unlink->list);
190			kfree(unlink);
191		}
192		list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free,
193					 list) {
194			list_del(&unlink->list);
195			kfree(unlink);
196		}
197		spin_unlock_irqrestore(&sdev->priv_lock, flags);
198	}
199}
200
201static void stub_device_reset(struct usbip_device *ud)
202{
203	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
204	struct usb_device *udev = sdev->udev;
205	int ret;
206
207	dev_dbg(&udev->dev, "device reset");
208
209	ret = usb_lock_device_for_reset(udev, NULL);
210	if (ret < 0) {
211		dev_err(&udev->dev, "lock for reset\n");
212		spin_lock_irq(&ud->lock);
213		ud->status = SDEV_ST_ERROR;
214		spin_unlock_irq(&ud->lock);
215		return;
216	}
217
218	/* try to reset the device */
219	ret = usb_reset_device(udev);
220	usb_unlock_device(udev);
221
222	spin_lock_irq(&ud->lock);
223	if (ret) {
224		dev_err(&udev->dev, "device reset\n");
225		ud->status = SDEV_ST_ERROR;
226	} else {
227		dev_info(&udev->dev, "device reset\n");
228		ud->status = SDEV_ST_AVAILABLE;
229	}
230	spin_unlock_irq(&ud->lock);
231}
232
233static void stub_device_unusable(struct usbip_device *ud)
234{
235	spin_lock_irq(&ud->lock);
236	ud->status = SDEV_ST_ERROR;
237	spin_unlock_irq(&ud->lock);
238}
239
240/**
241 * stub_device_alloc - allocate a new stub_device struct
242 * @udev: usb_device of a new device
243 *
244 * Allocates and initializes a new stub_device struct.
245 */
246static struct stub_device *stub_device_alloc(struct usb_device *udev)
247{
248	struct stub_device *sdev;
249	int busnum = udev->bus->busnum;
250	int devnum = udev->devnum;
251
252	dev_dbg(&udev->dev, "allocating stub device");
253
254	/* yes, it's a new device */
255	sdev = kzalloc(sizeof(struct stub_device), GFP_KERNEL);
256	if (!sdev)
257		return NULL;
258
259	sdev->udev = usb_get_dev(udev);
260
261	/*
262	 * devid is defined with devnum when this driver is first allocated.
263	 * devnum may change later if a device is reset. However, devid never
264	 * changes during a usbip connection.
265	 */
266	sdev->devid		= (busnum << 16) | devnum;
267	sdev->ud.side		= USBIP_STUB;
268	sdev->ud.status		= SDEV_ST_AVAILABLE;
269	spin_lock_init(&sdev->ud.lock);
 
270	sdev->ud.tcp_socket	= NULL;
271	sdev->ud.sockfd		= -1;
272
273	INIT_LIST_HEAD(&sdev->priv_init);
274	INIT_LIST_HEAD(&sdev->priv_tx);
275	INIT_LIST_HEAD(&sdev->priv_free);
276	INIT_LIST_HEAD(&sdev->unlink_free);
277	INIT_LIST_HEAD(&sdev->unlink_tx);
278	spin_lock_init(&sdev->priv_lock);
279
280	init_waitqueue_head(&sdev->tx_waitq);
281
282	sdev->ud.eh_ops.shutdown = stub_shutdown_connection;
283	sdev->ud.eh_ops.reset    = stub_device_reset;
284	sdev->ud.eh_ops.unusable = stub_device_unusable;
285
286	usbip_start_eh(&sdev->ud);
287
288	dev_dbg(&udev->dev, "register new device\n");
289
290	return sdev;
291}
292
293static void stub_device_free(struct stub_device *sdev)
294{
295	kfree(sdev);
296}
297
298static int stub_probe(struct usb_device *udev)
299{
300	struct stub_device *sdev = NULL;
301	const char *udev_busid = dev_name(&udev->dev);
302	struct bus_id_priv *busid_priv;
303	int rc = 0;
 
304
305	dev_dbg(&udev->dev, "Enter probe\n");
306
 
 
 
 
 
 
 
307	/* check we should claim or not by busid_table */
308	busid_priv = get_busid_priv(udev_busid);
309	if (!busid_priv || (busid_priv->status == STUB_BUSID_REMOV) ||
310	    (busid_priv->status == STUB_BUSID_OTHER)) {
311		dev_info(&udev->dev,
312			"%s is not in match_busid table... skip!\n",
313			udev_busid);
314
315		/*
316		 * Return value should be ENODEV or ENOXIO to continue trying
317		 * other matched drivers by the driver core.
318		 * See driver_probe_device() in driver/base/dd.c
319		 */
320		rc = -ENODEV;
 
 
 
321		goto call_put_busid_priv;
322	}
323
324	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB) {
325		dev_dbg(&udev->dev, "%s is a usb hub device... skip!\n",
326			 udev_busid);
327		rc = -ENODEV;
328		goto call_put_busid_priv;
329	}
330
331	if (!strcmp(udev->bus->bus_name, "vhci_hcd")) {
332		dev_dbg(&udev->dev,
333			"%s is attached on vhci_hcd... skip!\n",
334			udev_busid);
335
336		rc = -ENODEV;
337		goto call_put_busid_priv;
338	}
339
340	/* ok, this is my device */
341	sdev = stub_device_alloc(udev);
342	if (!sdev) {
343		rc = -ENOMEM;
344		goto call_put_busid_priv;
345	}
346
347	dev_info(&udev->dev,
348		"usbip-host: register new device (bus %u dev %u)\n",
349		udev->bus->busnum, udev->devnum);
350
351	busid_priv->shutdown_busid = 0;
352
353	/* set private data to usb_device */
354	dev_set_drvdata(&udev->dev, sdev);
 
355	busid_priv->sdev = sdev;
356	busid_priv->udev = udev;
357
 
 
 
 
 
 
358	/*
359	 * Claim this hub port.
360	 * It doesn't matter what value we pass as owner
361	 * (struct dev_state) as long as it is unique.
362	 */
363	rc = usb_hub_claim_port(udev->parent, udev->portnum,
364			(struct usb_dev_state *) udev);
365	if (rc) {
366		dev_dbg(&udev->dev, "unable to claim port\n");
367		goto err_port;
368	}
369
370	rc = stub_add_files(&udev->dev);
371	if (rc) {
372		dev_err(&udev->dev, "stub_add_files for %s\n", udev_busid);
373		goto err_files;
374	}
375	busid_priv->status = STUB_BUSID_ALLOC;
376
377	rc = 0;
378	goto call_put_busid_priv;
379
380err_files:
381	usb_hub_release_port(udev->parent, udev->portnum,
382			     (struct usb_dev_state *) udev);
383err_port:
384	dev_set_drvdata(&udev->dev, NULL);
385	usb_put_dev(udev);
386
 
 
387	busid_priv->sdev = NULL;
388	stub_device_free(sdev);
 
 
 
389
390call_put_busid_priv:
 
391	put_busid_priv(busid_priv);
 
 
 
 
 
392	return rc;
393}
394
395static void shutdown_busid(struct bus_id_priv *busid_priv)
396{
397	if (busid_priv->sdev && !busid_priv->shutdown_busid) {
398		busid_priv->shutdown_busid = 1;
399		usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
400
401		/* wait for the stop of the event handler */
402		usbip_stop_eh(&busid_priv->sdev->ud);
403	}
404}
405
406/*
407 * called in usb_disconnect() or usb_deregister()
408 * but only if actconfig(active configuration) exists
409 */
410static void stub_disconnect(struct usb_device *udev)
411{
412	struct stub_device *sdev;
413	const char *udev_busid = dev_name(&udev->dev);
414	struct bus_id_priv *busid_priv;
415	int rc;
416
417	dev_dbg(&udev->dev, "Enter disconnect\n");
418
419	busid_priv = get_busid_priv(udev_busid);
420	if (!busid_priv) {
421		BUG();
422		return;
423	}
424
425	sdev = dev_get_drvdata(&udev->dev);
426
427	/* get stub_device */
428	if (!sdev) {
429		dev_err(&udev->dev, "could not get device");
430		goto call_put_busid_priv;
 
 
431	}
432
433	dev_set_drvdata(&udev->dev, NULL);
434
 
 
 
435	/*
436	 * NOTE: rx/tx threads are invoked for each usb_device.
437	 */
438	stub_remove_files(&udev->dev);
439
440	/* release port */
441	rc = usb_hub_release_port(udev->parent, udev->portnum,
442				  (struct usb_dev_state *) udev);
443	if (rc) {
444		dev_dbg(&udev->dev, "unable to release port\n");
445		goto call_put_busid_priv;
 
 
 
 
 
446	}
447
448	/* If usb reset is called from event handler */
449	if (usbip_in_eh(current))
450		goto call_put_busid_priv;
 
 
 
 
 
 
 
451
452	/* shutdown the current connection */
453	shutdown_busid(busid_priv);
454
455	usb_put_dev(sdev->udev);
456
 
 
457	/* free sdev */
458	busid_priv->sdev = NULL;
459	stub_device_free(sdev);
460
461	if (busid_priv->status == STUB_BUSID_ALLOC)
462		busid_priv->status = STUB_BUSID_ADDED;
463
464call_put_busid_priv:
465	put_busid_priv(busid_priv);
466}
467
468#ifdef CONFIG_PM
469
470/* These functions need usb_port_suspend and usb_port_resume,
471 * which reside in drivers/usb/core/usb.h. Skip for now. */
472
473static int stub_suspend(struct usb_device *udev, pm_message_t message)
474{
475	dev_dbg(&udev->dev, "stub_suspend\n");
476
477	return 0;
478}
479
480static int stub_resume(struct usb_device *udev, pm_message_t message)
481{
482	dev_dbg(&udev->dev, "stub_resume\n");
483
484	return 0;
485}
486
487#endif	/* CONFIG_PM */
488
489struct usb_device_driver stub_driver = {
490	.name		= "usbip-host",
491	.probe		= stub_probe,
492	.disconnect	= stub_disconnect,
493#ifdef CONFIG_PM
494	.suspend	= stub_suspend,
495	.resume		= stub_resume,
496#endif
497	.supports_autosuspend	=	0,
 
498};