1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
4 * Copyright (C) 2015-2016 Samsung Electronics
5 *               Krzysztof Opasiak <k.opasiak@samsung.com>
6 */
7
8#include <asm/byteorder.h>
9#include <linux/file.h>
10#include <linux/fs.h>
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/stat.h>
14#include <linux/module.h>
15#include <linux/moduleparam.h>
16#include <net/sock.h>
17
18#include "usbip_common.h"
19
20#define DRIVER_AUTHOR "Takahiro Hirofuchi <hirofuchi@users.sourceforge.net>"
21#define DRIVER_DESC "USB/IP Core"
22
23#ifdef CONFIG_USBIP_DEBUG
24unsigned long usbip_debug_flag = 0xffffffff;
25#else
26unsigned long usbip_debug_flag;
27#endif
28EXPORT_SYMBOL_GPL(usbip_debug_flag);
29module_param(usbip_debug_flag, ulong, S_IRUGO|S_IWUSR);
30MODULE_PARM_DESC(usbip_debug_flag, "debug flags (defined in usbip_common.h)");
31
32/* FIXME */
33struct device_attribute dev_attr_usbip_debug;
34EXPORT_SYMBOL_GPL(dev_attr_usbip_debug);
35
36static ssize_t usbip_debug_show(struct device *dev,
37				struct device_attribute *attr, char *buf)
38{
39	return sprintf(buf, "%lx\n", usbip_debug_flag);
40}
41
42static ssize_t usbip_debug_store(struct device *dev,
43				 struct device_attribute *attr, const char *buf,
44				 size_t count)
45{
46	if (sscanf(buf, "%lx", &usbip_debug_flag) != 1)
47		return -EINVAL;
48	return count;
49}
50DEVICE_ATTR_RW(usbip_debug);
51
52static void usbip_dump_buffer(char *buff, int bufflen)
53{
54	print_hex_dump(KERN_DEBUG, "usbip-core", DUMP_PREFIX_OFFSET, 16, 4,
55		       buff, bufflen, false);
56}
57
58static void usbip_dump_pipe(unsigned int p)
59{
60	unsigned char type = usb_pipetype(p);
61	unsigned char ep   = usb_pipeendpoint(p);
62	unsigned char dev  = usb_pipedevice(p);
63	unsigned char dir  = usb_pipein(p);
64
65	pr_debug("dev(%d) ep(%d) [%s] ", dev, ep, dir ? "IN" : "OUT");
66
67	switch (type) {
68	case PIPE_ISOCHRONOUS:
69		pr_debug("ISO\n");
70		break;
71	case PIPE_INTERRUPT:
72		pr_debug("INT\n");
73		break;
74	case PIPE_CONTROL:
75		pr_debug("CTRL\n");
76		break;
77	case PIPE_BULK:
78		pr_debug("BULK\n");
79		break;
80	default:
81		pr_debug("ERR\n");
82		break;
83	}
84}
85
86static void usbip_dump_usb_device(struct usb_device *udev)
87{
88	struct device *dev = &udev->dev;
89	int i;
90
91	dev_dbg(dev, "       devnum(%d) devpath(%s) usb speed(%s)",
92		udev->devnum, udev->devpath, usb_speed_string(udev->speed));
93
94	pr_debug("tt hub ttport %d\n", udev->ttport);
95
96	dev_dbg(dev, "                    ");
97	for (i = 0; i < 16; i++)
98		pr_debug(" %2u", i);
99	pr_debug("\n");
100
101	dev_dbg(dev, "       toggle0(IN) :");
102	for (i = 0; i < 16; i++)
103		pr_debug(" %2u", (udev->toggle[0] & (1 << i)) ? 1 : 0);
104	pr_debug("\n");
105
106	dev_dbg(dev, "       toggle1(OUT):");
107	for (i = 0; i < 16; i++)
108		pr_debug(" %2u", (udev->toggle[1] & (1 << i)) ? 1 : 0);
109	pr_debug("\n");
110
111	dev_dbg(dev, "       epmaxp_in   :");
112	for (i = 0; i < 16; i++) {
113		if (udev->ep_in[i])
114			pr_debug(" %2u",
115			    le16_to_cpu(udev->ep_in[i]->desc.wMaxPacketSize));
116	}
117	pr_debug("\n");
118
119	dev_dbg(dev, "       epmaxp_out  :");
120	for (i = 0; i < 16; i++) {
121		if (udev->ep_out[i])
122			pr_debug(" %2u",
123			    le16_to_cpu(udev->ep_out[i]->desc.wMaxPacketSize));
124	}
125	pr_debug("\n");
126
127	dev_dbg(dev, "parent %s, bus %s\n", dev_name(&udev->parent->dev),
128		udev->bus->bus_name);
129
130	dev_dbg(dev, "have_langid %d, string_langid %d\n",
131		udev->have_langid, udev->string_langid);
132
133	dev_dbg(dev, "maxchild %d\n", udev->maxchild);
134}
135
136static void usbip_dump_request_type(__u8 rt)
137{
138	switch (rt & USB_RECIP_MASK) {
139	case USB_RECIP_DEVICE:
140		pr_debug("DEVICE");
141		break;
142	case USB_RECIP_INTERFACE:
143		pr_debug("INTERF");
144		break;
145	case USB_RECIP_ENDPOINT:
146		pr_debug("ENDPOI");
147		break;
148	case USB_RECIP_OTHER:
149		pr_debug("OTHER ");
150		break;
151	default:
152		pr_debug("------");
153		break;
154	}
155}
156
157static void usbip_dump_usb_ctrlrequest(struct usb_ctrlrequest *cmd)
158{
159	if (!cmd) {
160		pr_debug("       : null pointer\n");
161		return;
162	}
163
164	pr_debug("       ");
165	pr_debug("bRequestType(%02X) bRequest(%02X) wValue(%04X) wIndex(%04X) wLength(%04X) ",
166		 cmd->bRequestType, cmd->bRequest,
167		 cmd->wValue, cmd->wIndex, cmd->wLength);
168	pr_debug("\n       ");
169
170	if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
171		pr_debug("STANDARD ");
172		switch (cmd->bRequest) {
173		case USB_REQ_GET_STATUS:
174			pr_debug("GET_STATUS\n");
175			break;
176		case USB_REQ_CLEAR_FEATURE:
177			pr_debug("CLEAR_FEAT\n");
178			break;
179		case USB_REQ_SET_FEATURE:
180			pr_debug("SET_FEAT\n");
181			break;
182		case USB_REQ_SET_ADDRESS:
183			pr_debug("SET_ADDRRS\n");
184			break;
185		case USB_REQ_GET_DESCRIPTOR:
186			pr_debug("GET_DESCRI\n");
187			break;
188		case USB_REQ_SET_DESCRIPTOR:
189			pr_debug("SET_DESCRI\n");
190			break;
191		case USB_REQ_GET_CONFIGURATION:
192			pr_debug("GET_CONFIG\n");
193			break;
194		case USB_REQ_SET_CONFIGURATION:
195			pr_debug("SET_CONFIG\n");
196			break;
197		case USB_REQ_GET_INTERFACE:
198			pr_debug("GET_INTERF\n");
199			break;
200		case USB_REQ_SET_INTERFACE:
201			pr_debug("SET_INTERF\n");
202			break;
203		case USB_REQ_SYNCH_FRAME:
204			pr_debug("SYNC_FRAME\n");
205			break;
206		default:
207			pr_debug("REQ(%02X)\n", cmd->bRequest);
208			break;
209		}
210		usbip_dump_request_type(cmd->bRequestType);
211	} else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
212		pr_debug("CLASS\n");
213	} else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
214		pr_debug("VENDOR\n");
215	} else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_RESERVED) {
216		pr_debug("RESERVED\n");
217	}
218}
219
220void usbip_dump_urb(struct urb *urb)
221{
222	struct device *dev;
223
224	if (!urb) {
225		pr_debug("urb: null pointer!!\n");
226		return;
227	}
228
229	if (!urb->dev) {
230		pr_debug("urb->dev: null pointer!!\n");
231		return;
232	}
233
234	dev = &urb->dev->dev;
235
236	usbip_dump_usb_device(urb->dev);
237
238	dev_dbg(dev, "   pipe                  :%08x ", urb->pipe);
239
240	usbip_dump_pipe(urb->pipe);
241
242	dev_dbg(dev, "   status                :%d\n", urb->status);
243	dev_dbg(dev, "   transfer_flags        :%08X\n", urb->transfer_flags);
244	dev_dbg(dev, "   transfer_buffer_length:%d\n",
245						urb->transfer_buffer_length);
246	dev_dbg(dev, "   actual_length         :%d\n", urb->actual_length);
247
248	if (urb->setup_packet && usb_pipetype(urb->pipe) == PIPE_CONTROL)
249		usbip_dump_usb_ctrlrequest(
250			(struct usb_ctrlrequest *)urb->setup_packet);
251
252	dev_dbg(dev, "   start_frame           :%d\n", urb->start_frame);
253	dev_dbg(dev, "   number_of_packets     :%d\n", urb->number_of_packets);
254	dev_dbg(dev, "   interval              :%d\n", urb->interval);
255	dev_dbg(dev, "   error_count           :%d\n", urb->error_count);
256}
257EXPORT_SYMBOL_GPL(usbip_dump_urb);
258
259void usbip_dump_header(struct usbip_header *pdu)
260{
261	pr_debug("BASE: cmd %u seq %u devid %u dir %u ep %u\n",
262		 pdu->base.command,
263		 pdu->base.seqnum,
264		 pdu->base.devid,
265		 pdu->base.direction,
266		 pdu->base.ep);
267
268	switch (pdu->base.command) {
269	case USBIP_CMD_SUBMIT:
270		pr_debug("USBIP_CMD_SUBMIT: x_flags %u x_len %u sf %u #p %d iv %d\n",
271			 pdu->u.cmd_submit.transfer_flags,
272			 pdu->u.cmd_submit.transfer_buffer_length,
273			 pdu->u.cmd_submit.start_frame,
274			 pdu->u.cmd_submit.number_of_packets,
275			 pdu->u.cmd_submit.interval);
276		break;
277	case USBIP_CMD_UNLINK:
278		pr_debug("USBIP_CMD_UNLINK: seq %u\n",
279			 pdu->u.cmd_unlink.seqnum);
280		break;
281	case USBIP_RET_SUBMIT:
282		pr_debug("USBIP_RET_SUBMIT: st %d al %u sf %d #p %d ec %d\n",
283			 pdu->u.ret_submit.status,
284			 pdu->u.ret_submit.actual_length,
285			 pdu->u.ret_submit.start_frame,
286			 pdu->u.ret_submit.number_of_packets,
287			 pdu->u.ret_submit.error_count);
288		break;
289	case USBIP_RET_UNLINK:
290		pr_debug("USBIP_RET_UNLINK: status %d\n",
291			 pdu->u.ret_unlink.status);
292		break;
293	default:
294		/* NOT REACHED */
295		pr_err("unknown command\n");
296		break;
297	}
298}
299EXPORT_SYMBOL_GPL(usbip_dump_header);
300
301/* Receive data over TCP/IP. */
302int usbip_recv(struct socket *sock, void *buf, int size)
303{
304	int result;
305	struct kvec iov = {.iov_base = buf, .iov_len = size};
306	struct msghdr msg = {.msg_flags = MSG_NOSIGNAL};
307	int total = 0;
308
309	if (!sock || !buf || !size)
310		return -EINVAL;
311
312	iov_iter_kvec(&msg.msg_iter, ITER_DEST, &iov, 1, size);
313
314	usbip_dbg_xmit("enter\n");
315
316	do {
317		sock->sk->sk_allocation = GFP_NOIO;
318		sock->sk->sk_use_task_frag = false;
319
320		result = sock_recvmsg(sock, &msg, MSG_WAITALL);
321		if (result <= 0)
322			goto err;
323
324		total += result;
325	} while (msg_data_left(&msg));
326
327	if (usbip_dbg_flag_xmit) {
328		pr_debug("receiving....\n");
329		usbip_dump_buffer(buf, size);
330		pr_debug("received, osize %d ret %d size %zd total %d\n",
331			 size, result, msg_data_left(&msg), total);
332	}
333
334	return total;
335
336err:
337	return result;
338}
339EXPORT_SYMBOL_GPL(usbip_recv);
340
341/* there may be more cases to tweak the flags. */
342static unsigned int tweak_transfer_flags(unsigned int flags)
343{
344	flags &= ~URB_NO_TRANSFER_DMA_MAP;
345	return flags;
346}
347
348/*
349 * USBIP driver packs URB transfer flags in PDUs that are exchanged
350 * between Server (usbip_host) and Client (vhci_hcd). URB_* flags
351 * are internal to kernel and could change. Where as USBIP URB flags
352 * exchanged in PDUs are USBIP user API must not change.
353 *
354 * USBIP_URB* flags are exported as explicit API and client and server
355 * do mapping from kernel flags to USBIP_URB*. Details as follows:
356 *
357 * Client tx path (USBIP_CMD_SUBMIT):
358 * - Maps URB_* to USBIP_URB_* when it sends USBIP_CMD_SUBMIT packet.
359 *
360 * Server rx path (USBIP_CMD_SUBMIT):
361 * - Maps USBIP_URB_* to URB_* when it receives USBIP_CMD_SUBMIT packet.
362 *
363 * Flags aren't included in USBIP_CMD_UNLINK and USBIP_RET_SUBMIT packets
364 * and no special handling is needed for them in the following cases:
365 * - Server rx path (USBIP_CMD_UNLINK)
366 * - Client rx path & Server tx path (USBIP_RET_SUBMIT)
367 *
368 * Code paths:
369 * usbip_pack_pdu() is the common routine that handles packing pdu from
370 * urb and unpack pdu to an urb.
371 *
372 * usbip_pack_cmd_submit() and usbip_pack_ret_submit() handle
373 * USBIP_CMD_SUBMIT and USBIP_RET_SUBMIT respectively.
374 *
375 * usbip_map_urb_to_usbip() and usbip_map_usbip_to_urb() are used
376 * by usbip_pack_cmd_submit() and usbip_pack_ret_submit() to map
377 * flags.
378 */
379
380struct urb_to_usbip_flags {
381	u32 urb_flag;
382	u32 usbip_flag;
383};
384
385#define NUM_USBIP_FLAGS	17
386
387static const struct urb_to_usbip_flags flag_map[NUM_USBIP_FLAGS] = {
388	{URB_SHORT_NOT_OK, USBIP_URB_SHORT_NOT_OK},
389	{URB_ISO_ASAP, USBIP_URB_ISO_ASAP},
390	{URB_NO_TRANSFER_DMA_MAP, USBIP_URB_NO_TRANSFER_DMA_MAP},
391	{URB_ZERO_PACKET, USBIP_URB_ZERO_PACKET},
392	{URB_NO_INTERRUPT, USBIP_URB_NO_INTERRUPT},
393	{URB_FREE_BUFFER, USBIP_URB_FREE_BUFFER},
394	{URB_DIR_IN, USBIP_URB_DIR_IN},
395	{URB_DIR_OUT, USBIP_URB_DIR_OUT},
396	{URB_DIR_MASK, USBIP_URB_DIR_MASK},
397	{URB_DMA_MAP_SINGLE, USBIP_URB_DMA_MAP_SINGLE},
398	{URB_DMA_MAP_PAGE, USBIP_URB_DMA_MAP_PAGE},
399	{URB_DMA_MAP_SG, USBIP_URB_DMA_MAP_SG},
400	{URB_MAP_LOCAL, USBIP_URB_MAP_LOCAL},
401	{URB_SETUP_MAP_SINGLE, USBIP_URB_SETUP_MAP_SINGLE},
402	{URB_SETUP_MAP_LOCAL, USBIP_URB_SETUP_MAP_LOCAL},
403	{URB_DMA_SG_COMBINED, USBIP_URB_DMA_SG_COMBINED},
404	{URB_ALIGNED_TEMP_BUFFER, USBIP_URB_ALIGNED_TEMP_BUFFER},
405};
406
407static unsigned int urb_to_usbip(unsigned int flags)
408{
409	unsigned int map_flags = 0;
410	int loop;
411
412	for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) {
413		if (flags & flag_map[loop].urb_flag)
414			map_flags |= flag_map[loop].usbip_flag;
415	}
416
417	return map_flags;
418}
419
420static unsigned int usbip_to_urb(unsigned int flags)
421{
422	unsigned int map_flags = 0;
423	int loop;
424
425	for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) {
426		if (flags & flag_map[loop].usbip_flag)
427			map_flags |= flag_map[loop].urb_flag;
428	}
429
430	return map_flags;
431}
432
433static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
434				  int pack)
435{
436	struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
437
438	/*
439	 * Some members are not still implemented in usbip. I hope this issue
440	 * will be discussed when usbip is ported to other operating systems.
441	 */
442	if (pack) {
443		/* map after tweaking the urb flags */
444		spdu->transfer_flags = urb_to_usbip(tweak_transfer_flags(urb->transfer_flags));
445		spdu->transfer_buffer_length	= urb->transfer_buffer_length;
446		spdu->start_frame		= urb->start_frame;
447		spdu->number_of_packets		= urb->number_of_packets;
448		spdu->interval			= urb->interval;
449	} else  {
450		urb->transfer_flags         = usbip_to_urb(spdu->transfer_flags);
451		urb->transfer_buffer_length = spdu->transfer_buffer_length;
452		urb->start_frame            = spdu->start_frame;
453		urb->number_of_packets      = spdu->number_of_packets;
454		urb->interval               = spdu->interval;
455	}
456}
457
458static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
459				  int pack)
460{
461	struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
462
463	if (pack) {
464		rpdu->status		= urb->status;
465		rpdu->actual_length	= urb->actual_length;
466		rpdu->start_frame	= urb->start_frame;
467		rpdu->number_of_packets = urb->number_of_packets;
468		rpdu->error_count	= urb->error_count;
469	} else {
470		urb->status		= rpdu->status;
471		urb->actual_length	= rpdu->actual_length;
472		urb->start_frame	= rpdu->start_frame;
473		urb->number_of_packets = rpdu->number_of_packets;
474		urb->error_count	= rpdu->error_count;
475	}
476}
477
478void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
479		    int pack)
480{
481	switch (cmd) {
482	case USBIP_CMD_SUBMIT:
483		usbip_pack_cmd_submit(pdu, urb, pack);
484		break;
485	case USBIP_RET_SUBMIT:
486		usbip_pack_ret_submit(pdu, urb, pack);
487		break;
488	default:
489		/* NOT REACHED */
490		pr_err("unknown command\n");
491		break;
492	}
493}
494EXPORT_SYMBOL_GPL(usbip_pack_pdu);
495
496static void correct_endian_basic(struct usbip_header_basic *base, int send)
497{
498	if (send) {
499		base->command	= cpu_to_be32(base->command);
500		base->seqnum	= cpu_to_be32(base->seqnum);
501		base->devid	= cpu_to_be32(base->devid);
502		base->direction	= cpu_to_be32(base->direction);
503		base->ep	= cpu_to_be32(base->ep);
504	} else {
505		base->command	= be32_to_cpu(base->command);
506		base->seqnum	= be32_to_cpu(base->seqnum);
507		base->devid	= be32_to_cpu(base->devid);
508		base->direction	= be32_to_cpu(base->direction);
509		base->ep	= be32_to_cpu(base->ep);
510	}
511}
512
513static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
514				      int send)
515{
516	if (send) {
517		pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
518
519		cpu_to_be32s(&pdu->transfer_buffer_length);
520		cpu_to_be32s(&pdu->start_frame);
521		cpu_to_be32s(&pdu->number_of_packets);
522		cpu_to_be32s(&pdu->interval);
523	} else {
524		pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
525
526		be32_to_cpus(&pdu->transfer_buffer_length);
527		be32_to_cpus(&pdu->start_frame);
528		be32_to_cpus(&pdu->number_of_packets);
529		be32_to_cpus(&pdu->interval);
530	}
531}
532
533static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
534				      int send)
535{
536	if (send) {
537		cpu_to_be32s(&pdu->status);
538		cpu_to_be32s(&pdu->actual_length);
539		cpu_to_be32s(&pdu->start_frame);
540		cpu_to_be32s(&pdu->number_of_packets);
541		cpu_to_be32s(&pdu->error_count);
542	} else {
543		be32_to_cpus(&pdu->status);
544		be32_to_cpus(&pdu->actual_length);
545		be32_to_cpus(&pdu->start_frame);
546		be32_to_cpus(&pdu->number_of_packets);
547		be32_to_cpus(&pdu->error_count);
548	}
549}
550
551static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
552				      int send)
553{
554	if (send)
555		pdu->seqnum = cpu_to_be32(pdu->seqnum);
556	else
557		pdu->seqnum = be32_to_cpu(pdu->seqnum);
558}
559
560static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
561				      int send)
562{
563	if (send)
564		cpu_to_be32s(&pdu->status);
565	else
566		be32_to_cpus(&pdu->status);
567}
568
569void usbip_header_correct_endian(struct usbip_header *pdu, int send)
570{
571	__u32 cmd = 0;
572
573	if (send)
574		cmd = pdu->base.command;
575
576	correct_endian_basic(&pdu->base, send);
577
578	if (!send)
579		cmd = pdu->base.command;
580
581	switch (cmd) {
582	case USBIP_CMD_SUBMIT:
583		correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
584		break;
585	case USBIP_RET_SUBMIT:
586		correct_endian_ret_submit(&pdu->u.ret_submit, send);
587		break;
588	case USBIP_CMD_UNLINK:
589		correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
590		break;
591	case USBIP_RET_UNLINK:
592		correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
593		break;
594	default:
595		/* NOT REACHED */
596		pr_err("unknown command\n");
597		break;
598	}
599}
600EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
601
602static void usbip_iso_packet_correct_endian(
603		struct usbip_iso_packet_descriptor *iso, int send)
604{
605	/* does not need all members. but copy all simply. */
606	if (send) {
607		iso->offset	= cpu_to_be32(iso->offset);
608		iso->length	= cpu_to_be32(iso->length);
609		iso->status	= cpu_to_be32(iso->status);
610		iso->actual_length = cpu_to_be32(iso->actual_length);
611	} else {
612		iso->offset	= be32_to_cpu(iso->offset);
613		iso->length	= be32_to_cpu(iso->length);
614		iso->status	= be32_to_cpu(iso->status);
615		iso->actual_length = be32_to_cpu(iso->actual_length);
616	}
617}
618
619static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
620			   struct usb_iso_packet_descriptor *uiso, int pack)
621{
622	if (pack) {
623		iso->offset		= uiso->offset;
624		iso->length		= uiso->length;
625		iso->status		= uiso->status;
626		iso->actual_length	= uiso->actual_length;
627	} else {
628		uiso->offset		= iso->offset;
629		uiso->length		= iso->length;
630		uiso->status		= iso->status;
631		uiso->actual_length	= iso->actual_length;
632	}
633}
634
635/* must free buffer */
636struct usbip_iso_packet_descriptor*
637usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
638{
639	struct usbip_iso_packet_descriptor *iso;
640	int np = urb->number_of_packets;
641	ssize_t size = np * sizeof(*iso);
642	int i;
643
644	iso = kzalloc(size, GFP_KERNEL);
645	if (!iso)
646		return NULL;
647
648	for (i = 0; i < np; i++) {
649		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
650		usbip_iso_packet_correct_endian(&iso[i], 1);
651	}
652
653	*bufflen = size;
654
655	return iso;
656}
657EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
658
659/* some members of urb must be substituted before. */
660int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
661{
662	void *buff;
663	struct usbip_iso_packet_descriptor *iso;
664	int np = urb->number_of_packets;
665	int size = np * sizeof(*iso);
666	int i;
667	int ret;
668	int total_length = 0;
669
670	if (!usb_pipeisoc(urb->pipe))
671		return 0;
672
673	/* my Bluetooth dongle gets ISO URBs which are np = 0 */
674	if (np == 0)
675		return 0;
676
677	buff = kzalloc(size, GFP_KERNEL);
678	if (!buff)
679		return -ENOMEM;
680
681	ret = usbip_recv(ud->tcp_socket, buff, size);
682	if (ret != size) {
683		dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
684			ret);
685		kfree(buff);
686
687		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
688			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
689		else
690			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
691
692		return -EPIPE;
693	}
694
695	iso = (struct usbip_iso_packet_descriptor *) buff;
696	for (i = 0; i < np; i++) {
697		usbip_iso_packet_correct_endian(&iso[i], 0);
698		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
699		total_length += urb->iso_frame_desc[i].actual_length;
700	}
701
702	kfree(buff);
703
704	if (total_length != urb->actual_length) {
705		dev_err(&urb->dev->dev,
706			"total length of iso packets %d not equal to actual length of buffer %d\n",
707			total_length, urb->actual_length);
708
709		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
710			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
711		else
712			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
713
714		return -EPIPE;
715	}
716
717	return ret;
718}
719EXPORT_SYMBOL_GPL(usbip_recv_iso);
720
721/*
722 * This functions restores the padding which was removed for optimizing
723 * the bandwidth during transfer over tcp/ip
724 *
725 * buffer and iso packets need to be stored and be in propeper endian in urb
726 * before calling this function
727 */
728void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
729{
730	int np = urb->number_of_packets;
731	int i;
732	int actualoffset = urb->actual_length;
733
734	if (!usb_pipeisoc(urb->pipe))
735		return;
736
737	/* if no packets or length of data is 0, then nothing to unpack */
738	if (np == 0 || urb->actual_length == 0)
739		return;
740
741	/*
742	 * if actual_length is transfer_buffer_length then no padding is
743	 * present.
744	 */
745	if (urb->actual_length == urb->transfer_buffer_length)
746		return;
747
748	/*
749	 * loop over all packets from last to first (to prevent overwriting
750	 * memory when padding) and move them into the proper place
751	 */
752	for (i = np-1; i > 0; i--) {
753		actualoffset -= urb->iso_frame_desc[i].actual_length;
754		memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
755			urb->transfer_buffer + actualoffset,
756			urb->iso_frame_desc[i].actual_length);
757	}
758}
759EXPORT_SYMBOL_GPL(usbip_pad_iso);
760
761/* some members of urb must be substituted before. */
762int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
763{
764	struct scatterlist *sg;
765	int ret = 0;
766	int recv;
767	int size;
768	int copy;
769	int i;
770
771	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
772		/* the direction of urb must be OUT. */
773		if (usb_pipein(urb->pipe))
774			return 0;
775
776		size = urb->transfer_buffer_length;
777	} else {
778		/* the direction of urb must be IN. */
779		if (usb_pipeout(urb->pipe))
780			return 0;
781
782		size = urb->actual_length;
783	}
784
785	/* no need to recv xbuff */
786	if (!(size > 0))
787		return 0;
788
789	if (size > urb->transfer_buffer_length)
790		/* should not happen, probably malicious packet */
791		goto error;
792
793	if (urb->num_sgs) {
794		copy = size;
795		for_each_sg(urb->sg, sg, urb->num_sgs, i) {
796			int recv_size;
797
798			if (copy < sg->length)
799				recv_size = copy;
800			else
801				recv_size = sg->length;
802
803			recv = usbip_recv(ud->tcp_socket, sg_virt(sg),
804						recv_size);
805
806			if (recv != recv_size)
807				goto error;
808
809			copy -= recv;
810			ret += recv;
811
812			if (!copy)
813				break;
814		}
815
816		if (ret != size)
817			goto error;
818	} else {
819		ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
820		if (ret != size)
821			goto error;
822	}
823
824	return ret;
825
826error:
827	dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
828	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
829		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
830	else
831		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
832
833	return -EPIPE;
834}
835EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
836
837static int __init usbip_core_init(void)
838{
839	return usbip_init_eh();
840}
841
842static void __exit usbip_core_exit(void)
843{
844	usbip_finish_eh();
845	return;
846}
847
848module_init(usbip_core_init);
849module_exit(usbip_core_exit);
850
851MODULE_AUTHOR(DRIVER_AUTHOR);
852MODULE_DESCRIPTION(DRIVER_DESC);
853MODULE_LICENSE("GPL");
854