1/*
2 * Copyright (C) 2003-2008 Takahiro Hirofuchi
3 *
4 * This is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
17 * USA.
18 */
19
20#include <linux/init.h>
21#include <linux/file.h>
22#include <linux/kernel.h>
23#include <linux/kthread.h>
24#include <linux/module.h>
25#include <linux/platform_device.h>
26#include <linux/slab.h>
27
28#include "usbip_common.h"
29#include "vhci.h"
30
31#define DRIVER_AUTHOR "Takahiro Hirofuchi"
32#define DRIVER_DESC "USB/IP 'Virtual' Host Controller (VHCI) Driver"
33
34/*
35 * TODO
36 *	- update root hub emulation
37 *	- move the emulation code to userland ?
38 *		porting to other operating systems
39 *		minimize kernel code
40 *	- add suspend/resume code
41 *	- clean up everything
42 */
43
44/* See usb gadget dummy hcd */
45
46static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
47static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
48			    u16 wIndex, char *buff, u16 wLength);
49static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
50			    gfp_t mem_flags);
51static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
52static int vhci_start(struct usb_hcd *vhci_hcd);
53static void vhci_stop(struct usb_hcd *hcd);
54static int vhci_get_frame_number(struct usb_hcd *hcd);
55
56static const char driver_name[] = "vhci_hcd";
57static const char driver_desc[] = "USB/IP Virtual Host Controller";
58
59struct vhci_hcd *the_controller;
60
61static const char * const bit_desc[] = {
62	"CONNECTION",		/*0*/
63	"ENABLE",		/*1*/
64	"SUSPEND",		/*2*/
65	"OVER_CURRENT",		/*3*/
66	"RESET",		/*4*/
67	"R5",			/*5*/
68	"R6",			/*6*/
69	"R7",			/*7*/
70	"POWER",		/*8*/
71	"LOWSPEED",		/*9*/
72	"HIGHSPEED",		/*10*/
73	"PORT_TEST",		/*11*/
74	"INDICATOR",		/*12*/
75	"R13",			/*13*/
76	"R14",			/*14*/
77	"R15",			/*15*/
78	"C_CONNECTION",		/*16*/
79	"C_ENABLE",		/*17*/
80	"C_SUSPEND",		/*18*/
81	"C_OVER_CURRENT",	/*19*/
82	"C_RESET",		/*20*/
83	"R21",			/*21*/
84	"R22",			/*22*/
85	"R23",			/*23*/
86	"R24",			/*24*/
87	"R25",			/*25*/
88	"R26",			/*26*/
89	"R27",			/*27*/
90	"R28",			/*28*/
91	"R29",			/*29*/
92	"R30",			/*30*/
93	"R31",			/*31*/
94};
95
96static void dump_port_status_diff(u32 prev_status, u32 new_status)
97{
98	int i = 0;
99	u32 bit = 1;
100
101	pr_debug("status prev -> new: %08x -> %08x\n", prev_status, new_status);
102	while (bit) {
103		u32 prev = prev_status & bit;
104		u32 new = new_status & bit;
105		char change;
106
107		if (!prev && new)
108			change = '+';
109		else if (prev && !new)
110			change = '-';
111		else
112			change = ' ';
113
114		if (prev || new)
115			pr_debug(" %c%s\n", change, bit_desc[i]);
116		bit <<= 1;
117		i++;
118	}
119	pr_debug("\n");
120}
121
122void rh_port_connect(int rhport, enum usb_device_speed speed)
123{
124	usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
125
126	spin_lock(&the_controller->lock);
127
128	the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
129		| (1 << USB_PORT_FEAT_C_CONNECTION);
130
131	switch (speed) {
132	case USB_SPEED_HIGH:
133		the_controller->port_status[rhport] |= USB_PORT_STAT_HIGH_SPEED;
134		break;
135	case USB_SPEED_LOW:
136		the_controller->port_status[rhport] |= USB_PORT_STAT_LOW_SPEED;
137		break;
138	default:
139		break;
140	}
141
142	spin_unlock(&the_controller->lock);
143
144	usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
145}
146
147static void rh_port_disconnect(int rhport)
148{
149	usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
150
151	spin_lock(&the_controller->lock);
152
153	the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
154	the_controller->port_status[rhport] |=
155					(1 << USB_PORT_FEAT_C_CONNECTION);
156
157	spin_unlock(&the_controller->lock);
158	usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
159}
160
161#define PORT_C_MASK				\
162	((USB_PORT_STAT_C_CONNECTION		\
163	  | USB_PORT_STAT_C_ENABLE		\
164	  | USB_PORT_STAT_C_SUSPEND		\
165	  | USB_PORT_STAT_C_OVERCURRENT		\
166	  | USB_PORT_STAT_C_RESET) << 16)
167
168/*
169 * Returns 0 if the status hasn't changed, or the number of bytes in buf.
170 * Ports are 0-indexed from the HCD point of view,
171 * and 1-indexed from the USB core pointer of view.
172 *
173 * @buf: a bitmap to show which port status has been changed.
174 *  bit  0: reserved
175 *  bit  1: the status of port 0 has been changed.
176 *  bit  2: the status of port 1 has been changed.
177 *  ...
178 */
179static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
180{
181	struct vhci_hcd	*vhci;
182	int		retval;
183	int		rhport;
184	int		changed = 0;
185
186	retval = DIV_ROUND_UP(VHCI_NPORTS + 1, 8);
187	memset(buf, 0, retval);
188
189	vhci = hcd_to_vhci(hcd);
190
191	spin_lock(&vhci->lock);
192	if (!HCD_HW_ACCESSIBLE(hcd)) {
193		usbip_dbg_vhci_rh("hw accessible flag not on?\n");
194		goto done;
195	}
196
197	/* check pseudo status register for each port */
198	for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
199		if ((vhci->port_status[rhport] & PORT_C_MASK)) {
200			/* The status of a port has been changed, */
201			usbip_dbg_vhci_rh("port %d status changed\n", rhport);
202
203			buf[(rhport + 1) / 8] |= 1 << (rhport + 1) % 8;
204			changed = 1;
205		}
206	}
207
208	if ((hcd->state == HC_STATE_SUSPENDED) && (changed == 1))
209		usb_hcd_resume_root_hub(hcd);
210
211done:
212	spin_unlock(&vhci->lock);
213	return changed ? retval : 0;
214}
215
216static inline void hub_descriptor(struct usb_hub_descriptor *desc)
217{
218	memset(desc, 0, sizeof(*desc));
219	desc->bDescriptorType = USB_DT_HUB;
220	desc->bDescLength = 9;
221	desc->wHubCharacteristics = __constant_cpu_to_le16(
222		HUB_CHAR_INDV_PORT_LPSM | HUB_CHAR_COMMON_OCPM);
223	desc->bNbrPorts = VHCI_NPORTS;
224	desc->u.hs.DeviceRemovable[0] = 0xff;
225	desc->u.hs.DeviceRemovable[1] = 0xff;
226}
227
228static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
229			    u16 wIndex, char *buf, u16 wLength)
230{
231	struct vhci_hcd	*dum;
232	int             retval = 0;
233	int		rhport;
234
235	u32 prev_port_status[VHCI_NPORTS];
236
237	if (!HCD_HW_ACCESSIBLE(hcd))
238		return -ETIMEDOUT;
239
240	/*
241	 * NOTE:
242	 * wIndex shows the port number and begins from 1.
243	 */
244	usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
245			  wIndex);
246	if (wIndex > VHCI_NPORTS)
247		pr_err("invalid port number %d\n", wIndex);
248	rhport = ((__u8)(wIndex & 0x00ff)) - 1;
249
250	dum = hcd_to_vhci(hcd);
251
252	spin_lock(&dum->lock);
253
254	/* store old status and compare now and old later */
255	if (usbip_dbg_flag_vhci_rh) {
256		memcpy(prev_port_status, dum->port_status,
257			sizeof(prev_port_status));
258	}
259
260	switch (typeReq) {
261	case ClearHubFeature:
262		usbip_dbg_vhci_rh(" ClearHubFeature\n");
263		break;
264	case ClearPortFeature:
265		switch (wValue) {
266		case USB_PORT_FEAT_SUSPEND:
267			if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
268				/* 20msec signaling */
269				dum->resuming = 1;
270				dum->re_timeout =
271					jiffies + msecs_to_jiffies(20);
272			}
273			break;
274		case USB_PORT_FEAT_POWER:
275			usbip_dbg_vhci_rh(
276				" ClearPortFeature: USB_PORT_FEAT_POWER\n");
277			dum->port_status[rhport] = 0;
278			dum->resuming = 0;
279			break;
280		case USB_PORT_FEAT_C_RESET:
281			usbip_dbg_vhci_rh(
282				" ClearPortFeature: USB_PORT_FEAT_C_RESET\n");
283			switch (dum->vdev[rhport].speed) {
284			case USB_SPEED_HIGH:
285				dum->port_status[rhport] |=
286					USB_PORT_STAT_HIGH_SPEED;
287				break;
288			case USB_SPEED_LOW:
289				dum->port_status[rhport] |=
290					USB_PORT_STAT_LOW_SPEED;
291				break;
292			default:
293				break;
294			}
295		default:
296			usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
297					  wValue);
298			dum->port_status[rhport] &= ~(1 << wValue);
299			break;
300		}
301		break;
302	case GetHubDescriptor:
303		usbip_dbg_vhci_rh(" GetHubDescriptor\n");
304		hub_descriptor((struct usb_hub_descriptor *) buf);
305		break;
306	case GetHubStatus:
307		usbip_dbg_vhci_rh(" GetHubStatus\n");
308		*(__le32 *) buf = cpu_to_le32(0);
309		break;
310	case GetPortStatus:
311		usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
312		if (wIndex > VHCI_NPORTS || wIndex < 1) {
313			pr_err("invalid port number %d\n", wIndex);
314			retval = -EPIPE;
315		}
316
317		/* we do not care about resume. */
318
319		/* whoever resets or resumes must GetPortStatus to
320		 * complete it!!
321		 */
322		if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
323			dum->port_status[rhport] |=
324				(1 << USB_PORT_FEAT_C_SUSPEND);
325			dum->port_status[rhport] &=
326				~(1 << USB_PORT_FEAT_SUSPEND);
327			dum->resuming = 0;
328			dum->re_timeout = 0;
329		}
330
331		if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
332		    0 && time_after(jiffies, dum->re_timeout)) {
333			dum->port_status[rhport] |=
334				(1 << USB_PORT_FEAT_C_RESET);
335			dum->port_status[rhport] &=
336				~(1 << USB_PORT_FEAT_RESET);
337			dum->re_timeout = 0;
338
339			if (dum->vdev[rhport].ud.status ==
340			    VDEV_ST_NOTASSIGNED) {
341				usbip_dbg_vhci_rh(
342					" enable rhport %d (status %u)\n",
343					rhport,
344					dum->vdev[rhport].ud.status);
345				dum->port_status[rhport] |=
346					USB_PORT_STAT_ENABLE;
347			}
348		}
349		((__le16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
350		((__le16 *) buf)[1] =
351			cpu_to_le16(dum->port_status[rhport] >> 16);
352
353		usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
354				  ((u16 *)buf)[1]);
355		break;
356	case SetHubFeature:
357		usbip_dbg_vhci_rh(" SetHubFeature\n");
358		retval = -EPIPE;
359		break;
360	case SetPortFeature:
361		switch (wValue) {
362		case USB_PORT_FEAT_SUSPEND:
363			usbip_dbg_vhci_rh(
364				" SetPortFeature: USB_PORT_FEAT_SUSPEND\n");
365			break;
366		case USB_PORT_FEAT_RESET:
367			usbip_dbg_vhci_rh(
368				" SetPortFeature: USB_PORT_FEAT_RESET\n");
369			/* if it's already running, disconnect first */
370			if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
371				dum->port_status[rhport] &=
372					~(USB_PORT_STAT_ENABLE |
373					  USB_PORT_STAT_LOW_SPEED |
374					  USB_PORT_STAT_HIGH_SPEED);
375				/* FIXME test that code path! */
376			}
377			/* 50msec reset signaling */
378			dum->re_timeout = jiffies + msecs_to_jiffies(50);
379
380			/* FALLTHROUGH */
381		default:
382			usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
383					  wValue);
384			dum->port_status[rhport] |= (1 << wValue);
385			break;
386		}
387		break;
388
389	default:
390		pr_err("default: no such request\n");
391
392		/* "protocol stall" on error */
393		retval = -EPIPE;
394	}
395
396	if (usbip_dbg_flag_vhci_rh) {
397		pr_debug("port %d\n", rhport);
398		/* Only dump valid port status */
399		if (rhport >= 0) {
400			dump_port_status_diff(prev_port_status[rhport],
401					      dum->port_status[rhport]);
402		}
403	}
404	usbip_dbg_vhci_rh(" bye\n");
405
406	spin_unlock(&dum->lock);
407
408	return retval;
409}
410
411static struct vhci_device *get_vdev(struct usb_device *udev)
412{
413	int i;
414
415	if (!udev)
416		return NULL;
417
418	for (i = 0; i < VHCI_NPORTS; i++)
419		if (the_controller->vdev[i].udev == udev)
420			return port_to_vdev(i);
421
422	return NULL;
423}
424
425static void vhci_tx_urb(struct urb *urb)
426{
427	struct vhci_device *vdev = get_vdev(urb->dev);
428	struct vhci_priv *priv;
429
430	if (!vdev) {
431		pr_err("could not get virtual device");
432		return;
433	}
434
435	priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
436	if (!priv) {
437		usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
438		return;
439	}
440
441	spin_lock(&vdev->priv_lock);
442
443	priv->seqnum = atomic_inc_return(&the_controller->seqnum);
444	if (priv->seqnum == 0xffff)
445		dev_info(&urb->dev->dev, "seqnum max\n");
446
447	priv->vdev = vdev;
448	priv->urb = urb;
449
450	urb->hcpriv = (void *) priv;
451
452	list_add_tail(&priv->list, &vdev->priv_tx);
453
454	wake_up(&vdev->waitq_tx);
455	spin_unlock(&vdev->priv_lock);
456}
457
458static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
459			    gfp_t mem_flags)
460{
461	struct device *dev = &urb->dev->dev;
462	int ret = 0;
463	struct vhci_device *vdev;
464
465	usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
466			  hcd, urb, mem_flags);
467
468	/* patch to usb_sg_init() is in 2.5.60 */
469	BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
470
471	spin_lock(&the_controller->lock);
472
473	if (urb->status != -EINPROGRESS) {
474		dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
475		spin_unlock(&the_controller->lock);
476		return urb->status;
477	}
478
479	vdev = port_to_vdev(urb->dev->portnum-1);
480
481	/* refuse enqueue for dead connection */
482	spin_lock(&vdev->ud.lock);
483	if (vdev->ud.status == VDEV_ST_NULL ||
484	    vdev->ud.status == VDEV_ST_ERROR) {
485		dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
486		spin_unlock(&vdev->ud.lock);
487		spin_unlock(&the_controller->lock);
488		return -ENODEV;
489	}
490	spin_unlock(&vdev->ud.lock);
491
492	ret = usb_hcd_link_urb_to_ep(hcd, urb);
493	if (ret)
494		goto no_need_unlink;
495
496	/*
497	 * The enumeration process is as follows;
498	 *
499	 *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
500	 *     to get max packet length of default pipe
501	 *
502	 *  2. Set_Address request to DevAddr(0) EndPoint(0)
503	 *
504	 */
505	if (usb_pipedevice(urb->pipe) == 0) {
506		__u8 type = usb_pipetype(urb->pipe);
507		struct usb_ctrlrequest *ctrlreq =
508			(struct usb_ctrlrequest *) urb->setup_packet;
509
510		if (type != PIPE_CONTROL || !ctrlreq) {
511			dev_err(dev, "invalid request to devnum 0\n");
512			ret = -EINVAL;
513			goto no_need_xmit;
514		}
515
516		switch (ctrlreq->bRequest) {
517		case USB_REQ_SET_ADDRESS:
518			/* set_address may come when a device is reset */
519			dev_info(dev, "SetAddress Request (%d) to port %d\n",
520				 ctrlreq->wValue, vdev->rhport);
521
522			usb_put_dev(vdev->udev);
523			vdev->udev = usb_get_dev(urb->dev);
524
525			spin_lock(&vdev->ud.lock);
526			vdev->ud.status = VDEV_ST_USED;
527			spin_unlock(&vdev->ud.lock);
528
529			if (urb->status == -EINPROGRESS) {
530				/* This request is successfully completed. */
531				/* If not -EINPROGRESS, possibly unlinked. */
532				urb->status = 0;
533			}
534
535			goto no_need_xmit;
536
537		case USB_REQ_GET_DESCRIPTOR:
538			if (ctrlreq->wValue == cpu_to_le16(USB_DT_DEVICE << 8))
539				usbip_dbg_vhci_hc(
540					"Not yet?:Get_Descriptor to device 0 (get max pipe size)\n");
541
542			usb_put_dev(vdev->udev);
543			vdev->udev = usb_get_dev(urb->dev);
544			goto out;
545
546		default:
547			/* NOT REACHED */
548			dev_err(dev,
549				"invalid request to devnum 0 bRequest %u, wValue %u\n",
550				ctrlreq->bRequest,
551				ctrlreq->wValue);
552			ret =  -EINVAL;
553			goto no_need_xmit;
554		}
555
556	}
557
558out:
559	vhci_tx_urb(urb);
560	spin_unlock(&the_controller->lock);
561
562	return 0;
563
564no_need_xmit:
565	usb_hcd_unlink_urb_from_ep(hcd, urb);
566no_need_unlink:
567	spin_unlock(&the_controller->lock);
568	usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
569	return ret;
570}
571
572/*
573 * vhci_rx gives back the urb after receiving the reply of the urb.  If an
574 * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
575 * back its urb. For the driver unlinking the urb, the content of the urb is
576 * not important, but the calling to its completion handler is important; the
577 * completion of unlinking is notified by the completion handler.
578 *
579 *
580 * CLIENT SIDE
581 *
582 * - When vhci_hcd receives RET_SUBMIT,
583 *
584 *	- case 1a). the urb of the pdu is not unlinking.
585 *		- normal case
586 *		=> just give back the urb
587 *
588 *	- case 1b). the urb of the pdu is unlinking.
589 *		- usbip.ko will return a reply of the unlinking request.
590 *		=> give back the urb now and go to case 2b).
591 *
592 * - When vhci_hcd receives RET_UNLINK,
593 *
594 *	- case 2a). a submit request is still pending in vhci_hcd.
595 *		- urb was really pending in usbip.ko and urb_unlink_urb() was
596 *		  completed there.
597 *		=> free a pending submit request
598 *		=> notify unlink completeness by giving back the urb
599 *
600 *	- case 2b). a submit request is *not* pending in vhci_hcd.
601 *		- urb was already given back to the core driver.
602 *		=> do not give back the urb
603 *
604 *
605 * SERVER SIDE
606 *
607 * - When usbip receives CMD_UNLINK,
608 *
609 *	- case 3a). the urb of the unlink request is now in submission.
610 *		=> do usb_unlink_urb().
611 *		=> after the unlink is completed, send RET_UNLINK.
612 *
613 *	- case 3b). the urb of the unlink request is not in submission.
614 *		- may be already completed or never be received
615 *		=> send RET_UNLINK
616 *
617 */
618static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
619{
620	struct vhci_priv *priv;
621	struct vhci_device *vdev;
622
623	pr_info("dequeue a urb %p\n", urb);
624
625	spin_lock(&the_controller->lock);
626
627	priv = urb->hcpriv;
628	if (!priv) {
629		/* URB was never linked! or will be soon given back by
630		 * vhci_rx. */
631		spin_unlock(&the_controller->lock);
632		return 0;
633	}
634
635	{
636		int ret = 0;
637
638		ret = usb_hcd_check_unlink_urb(hcd, urb, status);
639		if (ret) {
640			spin_unlock(&the_controller->lock);
641			return ret;
642		}
643	}
644
645	 /* send unlink request here? */
646	vdev = priv->vdev;
647
648	if (!vdev->ud.tcp_socket) {
649		/* tcp connection is closed */
650		spin_lock(&vdev->priv_lock);
651
652		pr_info("device %p seems to be disconnected\n", vdev);
653		list_del(&priv->list);
654		kfree(priv);
655		urb->hcpriv = NULL;
656
657		spin_unlock(&vdev->priv_lock);
658
659		/*
660		 * If tcp connection is alive, we have sent CMD_UNLINK.
661		 * vhci_rx will receive RET_UNLINK and give back the URB.
662		 * Otherwise, we give back it here.
663		 */
664		pr_info("gives back urb %p\n", urb);
665
666		usb_hcd_unlink_urb_from_ep(hcd, urb);
667
668		spin_unlock(&the_controller->lock);
669		usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
670				     urb->status);
671		spin_lock(&the_controller->lock);
672
673	} else {
674		/* tcp connection is alive */
675		struct vhci_unlink *unlink;
676
677		spin_lock(&vdev->priv_lock);
678
679		/* setup CMD_UNLINK pdu */
680		unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
681		if (!unlink) {
682			spin_unlock(&vdev->priv_lock);
683			spin_unlock(&the_controller->lock);
684			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
685			return -ENOMEM;
686		}
687
688		unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
689		if (unlink->seqnum == 0xffff)
690			pr_info("seqnum max\n");
691
692		unlink->unlink_seqnum = priv->seqnum;
693
694		pr_info("device %p seems to be still connected\n", vdev);
695
696		/* send cmd_unlink and try to cancel the pending URB in the
697		 * peer */
698		list_add_tail(&unlink->list, &vdev->unlink_tx);
699		wake_up(&vdev->waitq_tx);
700
701		spin_unlock(&vdev->priv_lock);
702	}
703
704	spin_unlock(&the_controller->lock);
705
706	usbip_dbg_vhci_hc("leave\n");
707	return 0;
708}
709
710static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
711{
712	struct vhci_unlink *unlink, *tmp;
713
714	spin_lock(&the_controller->lock);
715	spin_lock(&vdev->priv_lock);
716
717	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
718		pr_info("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
719		list_del(&unlink->list);
720		kfree(unlink);
721	}
722
723	while (!list_empty(&vdev->unlink_rx)) {
724		struct urb *urb;
725
726		unlink = list_first_entry(&vdev->unlink_rx, struct vhci_unlink,
727			list);
728
729		/* give back URB of unanswered unlink request */
730		pr_info("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
731
732		urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
733		if (!urb) {
734			pr_info("the urb (seqnum %lu) was already given back\n",
735				unlink->unlink_seqnum);
736			list_del(&unlink->list);
737			kfree(unlink);
738			continue;
739		}
740
741		urb->status = -ENODEV;
742
743		usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
744
745		list_del(&unlink->list);
746
747		spin_unlock(&vdev->priv_lock);
748		spin_unlock(&the_controller->lock);
749
750		usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
751				     urb->status);
752
753		spin_lock(&the_controller->lock);
754		spin_lock(&vdev->priv_lock);
755
756		kfree(unlink);
757	}
758
759	spin_unlock(&vdev->priv_lock);
760	spin_unlock(&the_controller->lock);
761}
762
763/*
764 * The important thing is that only one context begins cleanup.
765 * This is why error handling and cleanup become simple.
766 * We do not want to consider race condition as possible.
767 */
768static void vhci_shutdown_connection(struct usbip_device *ud)
769{
770	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
771
772	/* need this? see stub_dev.c */
773	if (ud->tcp_socket) {
774		pr_debug("shutdown tcp_socket %p\n", ud->tcp_socket);
775		kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
776	}
777
778	/* kill threads related to this sdev */
779	if (vdev->ud.tcp_rx) {
780		kthread_stop_put(vdev->ud.tcp_rx);
781		vdev->ud.tcp_rx = NULL;
782	}
783	if (vdev->ud.tcp_tx) {
784		kthread_stop_put(vdev->ud.tcp_tx);
785		vdev->ud.tcp_tx = NULL;
786	}
787	pr_info("stop threads\n");
788
789	/* active connection is closed */
790	if (vdev->ud.tcp_socket) {
791		sockfd_put(vdev->ud.tcp_socket);
792		vdev->ud.tcp_socket = NULL;
793	}
794	pr_info("release socket\n");
795
796	vhci_device_unlink_cleanup(vdev);
797
798	/*
799	 * rh_port_disconnect() is a trigger of ...
800	 *   usb_disable_device():
801	 *	disable all the endpoints for a USB device.
802	 *   usb_disable_endpoint():
803	 *	disable endpoints. pending urbs are unlinked(dequeued).
804	 *
805	 * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
806	 * detached device should release used urbs in a cleanup function (i.e.
807	 * xxx_disconnect()). Therefore, vhci_hcd does not need to release
808	 * pushed urbs and their private data in this function.
809	 *
810	 * NOTE: vhci_dequeue() must be considered carefully. When shutting down
811	 * a connection, vhci_shutdown_connection() expects vhci_dequeue()
812	 * gives back pushed urbs and frees their private data by request of
813	 * the cleanup function of a USB driver. When unlinking a urb with an
814	 * active connection, vhci_dequeue() does not give back the urb which
815	 * is actually given back by vhci_rx after receiving its return pdu.
816	 *
817	 */
818	rh_port_disconnect(vdev->rhport);
819
820	pr_info("disconnect device\n");
821}
822
823
824static void vhci_device_reset(struct usbip_device *ud)
825{
826	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
827
828	spin_lock(&ud->lock);
829
830	vdev->speed  = 0;
831	vdev->devid  = 0;
832
833	usb_put_dev(vdev->udev);
834	vdev->udev = NULL;
835
836	if (ud->tcp_socket) {
837		sockfd_put(ud->tcp_socket);
838		ud->tcp_socket = NULL;
839	}
840	ud->status = VDEV_ST_NULL;
841
842	spin_unlock(&ud->lock);
843}
844
845static void vhci_device_unusable(struct usbip_device *ud)
846{
847	spin_lock(&ud->lock);
848	ud->status = VDEV_ST_ERROR;
849	spin_unlock(&ud->lock);
850}
851
852static void vhci_device_init(struct vhci_device *vdev)
853{
854	memset(vdev, 0, sizeof(*vdev));
855
856	vdev->ud.side   = USBIP_VHCI;
857	vdev->ud.status = VDEV_ST_NULL;
858	spin_lock_init(&vdev->ud.lock);
859
860	INIT_LIST_HEAD(&vdev->priv_rx);
861	INIT_LIST_HEAD(&vdev->priv_tx);
862	INIT_LIST_HEAD(&vdev->unlink_tx);
863	INIT_LIST_HEAD(&vdev->unlink_rx);
864	spin_lock_init(&vdev->priv_lock);
865
866	init_waitqueue_head(&vdev->waitq_tx);
867
868	vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
869	vdev->ud.eh_ops.reset = vhci_device_reset;
870	vdev->ud.eh_ops.unusable = vhci_device_unusable;
871
872	usbip_start_eh(&vdev->ud);
873}
874
875static int vhci_start(struct usb_hcd *hcd)
876{
877	struct vhci_hcd *vhci = hcd_to_vhci(hcd);
878	int rhport;
879	int err = 0;
880
881	usbip_dbg_vhci_hc("enter vhci_start\n");
882
883	/* initialize private data of usb_hcd */
884
885	for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
886		struct vhci_device *vdev = &vhci->vdev[rhport];
887
888		vhci_device_init(vdev);
889		vdev->rhport = rhport;
890	}
891
892	atomic_set(&vhci->seqnum, 0);
893	spin_lock_init(&vhci->lock);
894
895	hcd->power_budget = 0; /* no limit */
896	hcd->uses_new_polling = 1;
897
898	/* vhci_hcd is now ready to be controlled through sysfs */
899	err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
900	if (err) {
901		pr_err("create sysfs files\n");
902		return err;
903	}
904
905	return 0;
906}
907
908static void vhci_stop(struct usb_hcd *hcd)
909{
910	struct vhci_hcd *vhci = hcd_to_vhci(hcd);
911	int rhport = 0;
912
913	usbip_dbg_vhci_hc("stop VHCI controller\n");
914
915	/* 1. remove the userland interface of vhci_hcd */
916	sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
917
918	/* 2. shutdown all the ports of vhci_hcd */
919	for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
920		struct vhci_device *vdev = &vhci->vdev[rhport];
921
922		usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
923		usbip_stop_eh(&vdev->ud);
924	}
925}
926
927static int vhci_get_frame_number(struct usb_hcd *hcd)
928{
929	pr_err("Not yet implemented\n");
930	return 0;
931}
932
933#ifdef CONFIG_PM
934
935/* FIXME: suspend/resume */
936static int vhci_bus_suspend(struct usb_hcd *hcd)
937{
938	struct vhci_hcd *vhci = hcd_to_vhci(hcd);
939
940	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
941
942	spin_lock(&vhci->lock);
943	hcd->state = HC_STATE_SUSPENDED;
944	spin_unlock(&vhci->lock);
945
946	return 0;
947}
948
949static int vhci_bus_resume(struct usb_hcd *hcd)
950{
951	struct vhci_hcd *vhci = hcd_to_vhci(hcd);
952	int rc = 0;
953
954	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
955
956	spin_lock(&vhci->lock);
957	if (!HCD_HW_ACCESSIBLE(hcd))
958		rc = -ESHUTDOWN;
959	else
960		hcd->state = HC_STATE_RUNNING;
961	spin_unlock(&vhci->lock);
962
963	return rc;
964}
965
966#else
967
968#define vhci_bus_suspend      NULL
969#define vhci_bus_resume       NULL
970#endif
971
972static struct hc_driver vhci_hc_driver = {
973	.description	= driver_name,
974	.product_desc	= driver_desc,
975	.hcd_priv_size	= sizeof(struct vhci_hcd),
976
977	.flags		= HCD_USB2,
978
979	.start		= vhci_start,
980	.stop		= vhci_stop,
981
982	.urb_enqueue	= vhci_urb_enqueue,
983	.urb_dequeue	= vhci_urb_dequeue,
984
985	.get_frame_number = vhci_get_frame_number,
986
987	.hub_status_data = vhci_hub_status,
988	.hub_control    = vhci_hub_control,
989	.bus_suspend	= vhci_bus_suspend,
990	.bus_resume	= vhci_bus_resume,
991};
992
993static int vhci_hcd_probe(struct platform_device *pdev)
994{
995	struct usb_hcd		*hcd;
996	int			ret;
997
998	usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
999
1000	/*
1001	 * Allocate and initialize hcd.
1002	 * Our private data is also allocated automatically.
1003	 */
1004	hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1005	if (!hcd) {
1006		pr_err("create hcd failed\n");
1007		return -ENOMEM;
1008	}
1009	hcd->has_tt = 1;
1010
1011	/* this is private data for vhci_hcd */
1012	the_controller = hcd_to_vhci(hcd);
1013
1014	/*
1015	 * Finish generic HCD structure initialization and register.
1016	 * Call the driver's reset() and start() routines.
1017	 */
1018	ret = usb_add_hcd(hcd, 0, 0);
1019	if (ret != 0) {
1020		pr_err("usb_add_hcd failed %d\n", ret);
1021		usb_put_hcd(hcd);
1022		the_controller = NULL;
1023		return ret;
1024	}
1025
1026	usbip_dbg_vhci_hc("bye\n");
1027	return 0;
1028}
1029
1030static int vhci_hcd_remove(struct platform_device *pdev)
1031{
1032	struct usb_hcd	*hcd;
1033
1034	hcd = platform_get_drvdata(pdev);
1035	if (!hcd)
1036		return 0;
1037
1038	/*
1039	 * Disconnects the root hub,
1040	 * then reverses the effects of usb_add_hcd(),
1041	 * invoking the HCD's stop() methods.
1042	 */
1043	usb_remove_hcd(hcd);
1044	usb_put_hcd(hcd);
1045	the_controller = NULL;
1046
1047	return 0;
1048}
1049
1050#ifdef CONFIG_PM
1051
1052/* what should happen for USB/IP under suspend/resume? */
1053static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1054{
1055	struct usb_hcd *hcd;
1056	int rhport = 0;
1057	int connected = 0;
1058	int ret = 0;
1059
1060	hcd = platform_get_drvdata(pdev);
1061
1062	spin_lock(&the_controller->lock);
1063
1064	for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
1065		if (the_controller->port_status[rhport] &
1066		    USB_PORT_STAT_CONNECTION)
1067			connected += 1;
1068
1069	spin_unlock(&the_controller->lock);
1070
1071	if (connected > 0) {
1072		dev_info(&pdev->dev,
1073			 "We have %d active connection%s. Do not suspend.\n",
1074			 connected, (connected == 1 ? "" : "s"));
1075		ret =  -EBUSY;
1076	} else {
1077		dev_info(&pdev->dev, "suspend vhci_hcd");
1078		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1079	}
1080
1081	return ret;
1082}
1083
1084static int vhci_hcd_resume(struct platform_device *pdev)
1085{
1086	struct usb_hcd *hcd;
1087
1088	dev_dbg(&pdev->dev, "%s\n", __func__);
1089
1090	hcd = platform_get_drvdata(pdev);
1091	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1092	usb_hcd_poll_rh_status(hcd);
1093
1094	return 0;
1095}
1096
1097#else
1098
1099#define vhci_hcd_suspend	NULL
1100#define vhci_hcd_resume		NULL
1101
1102#endif
1103
1104static struct platform_driver vhci_driver = {
1105	.probe	= vhci_hcd_probe,
1106	.remove	= vhci_hcd_remove,
1107	.suspend = vhci_hcd_suspend,
1108	.resume	= vhci_hcd_resume,
1109	.driver	= {
1110		.name = driver_name,
1111	},
1112};
1113
1114/*
1115 * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
1116 * We need to add this virtual device as a platform device arbitrarily:
1117 *	1. platform_device_register()
1118 */
1119static void the_pdev_release(struct device *dev)
1120{
1121}
1122
1123static struct platform_device the_pdev = {
1124	/* should be the same name as driver_name */
1125	.name = driver_name,
1126	.id = -1,
1127	.dev = {
1128		.release = the_pdev_release,
1129	},
1130};
1131
1132static int __init vhci_hcd_init(void)
1133{
1134	int ret;
1135
1136	if (usb_disabled())
1137		return -ENODEV;
1138
1139	ret = platform_driver_register(&vhci_driver);
1140	if (ret)
1141		goto err_driver_register;
1142
1143	ret = platform_device_register(&the_pdev);
1144	if (ret)
1145		goto err_platform_device_register;
1146
1147	pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
1148	return ret;
1149
1150err_platform_device_register:
1151	platform_driver_unregister(&vhci_driver);
1152err_driver_register:
1153	return ret;
1154}
1155
1156static void __exit vhci_hcd_exit(void)
1157{
1158	platform_device_unregister(&the_pdev);
1159	platform_driver_unregister(&vhci_driver);
1160}
1161
1162module_init(vhci_hcd_init);
1163module_exit(vhci_hcd_exit);
1164
1165MODULE_AUTHOR(DRIVER_AUTHOR);
1166MODULE_DESCRIPTION(DRIVER_DESC);
1167MODULE_LICENSE("GPL");
1168MODULE_VERSION(USBIP_VERSION);
1169