usbip_common.c

  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		/*
474		 * The number_of_packets field determines the length of
475		 * iso_frame_desc[], which is a flexible array allocated
476		 * at URB creation time. A response must never claim more
477		 * packets than originally submitted; doing so would cause
478		 * an out-of-bounds write in usbip_recv_iso() and
479		 * usbip_pad_iso(). Clamp to zero on violation so both
480		 * functions safely return early.
481		 */
482		if (rpdu->number_of_packets < 0 ||
483		    rpdu->number_of_packets > urb->number_of_packets)
484			rpdu->number_of_packets = 0;
485		urb->number_of_packets = rpdu->number_of_packets;
486		urb->error_count	= rpdu->error_count;
487	}
488}
489
490void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
491		    int pack)
492{
493	switch (cmd) {
494	case USBIP_CMD_SUBMIT:
495		usbip_pack_cmd_submit(pdu, urb, pack);
496		break;
497	case USBIP_RET_SUBMIT:
498		usbip_pack_ret_submit(pdu, urb, pack);
499		break;
500	default:
501		/* NOT REACHED */
502		pr_err("unknown command\n");
503		break;
504	}
505}
506EXPORT_SYMBOL_GPL(usbip_pack_pdu);
507
508static void correct_endian_basic(struct usbip_header_basic *base, int send)
509{
510	if (send) {
511		base->command	= cpu_to_be32(base->command);
512		base->seqnum	= cpu_to_be32(base->seqnum);
513		base->devid	= cpu_to_be32(base->devid);
514		base->direction	= cpu_to_be32(base->direction);
515		base->ep	= cpu_to_be32(base->ep);
516	} else {
517		base->command	= be32_to_cpu(base->command);
518		base->seqnum	= be32_to_cpu(base->seqnum);
519		base->devid	= be32_to_cpu(base->devid);
520		base->direction	= be32_to_cpu(base->direction);
521		base->ep	= be32_to_cpu(base->ep);
522	}
523}
524
525static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
526				      int send)
527{
528	if (send) {
529		pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
530
531		cpu_to_be32s(&pdu->transfer_buffer_length);
532		cpu_to_be32s(&pdu->start_frame);
533		cpu_to_be32s(&pdu->number_of_packets);
534		cpu_to_be32s(&pdu->interval);
535	} else {
536		pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
537
538		be32_to_cpus(&pdu->transfer_buffer_length);
539		be32_to_cpus(&pdu->start_frame);
540		be32_to_cpus(&pdu->number_of_packets);
541		be32_to_cpus(&pdu->interval);
542	}
543}
544
545static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
546				      int send)
547{
548	if (send) {
549		cpu_to_be32s(&pdu->status);
550		cpu_to_be32s(&pdu->actual_length);
551		cpu_to_be32s(&pdu->start_frame);
552		cpu_to_be32s(&pdu->number_of_packets);
553		cpu_to_be32s(&pdu->error_count);
554	} else {
555		be32_to_cpus(&pdu->status);
556		be32_to_cpus(&pdu->actual_length);
557		be32_to_cpus(&pdu->start_frame);
558		be32_to_cpus(&pdu->number_of_packets);
559		be32_to_cpus(&pdu->error_count);
560	}
561}
562
563static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
564				      int send)
565{
566	if (send)
567		pdu->seqnum = cpu_to_be32(pdu->seqnum);
568	else
569		pdu->seqnum = be32_to_cpu(pdu->seqnum);
570}
571
572static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
573				      int send)
574{
575	if (send)
576		cpu_to_be32s(&pdu->status);
577	else
578		be32_to_cpus(&pdu->status);
579}
580
581void usbip_header_correct_endian(struct usbip_header *pdu, int send)
582{
583	__u32 cmd = 0;
584
585	if (send)
586		cmd = pdu->base.command;
587
588	correct_endian_basic(&pdu->base, send);
589
590	if (!send)
591		cmd = pdu->base.command;
592
593	switch (cmd) {
594	case USBIP_CMD_SUBMIT:
595		correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
596		break;
597	case USBIP_RET_SUBMIT:
598		correct_endian_ret_submit(&pdu->u.ret_submit, send);
599		break;
600	case USBIP_CMD_UNLINK:
601		correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
602		break;
603	case USBIP_RET_UNLINK:
604		correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
605		break;
606	default:
607		/* NOT REACHED */
608		pr_err("unknown command\n");
609		break;
610	}
611}
612EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
613
614static void usbip_iso_packet_correct_endian(
615		struct usbip_iso_packet_descriptor *iso, int send)
616{
617	/* does not need all members. but copy all simply. */
618	if (send) {
619		iso->offset	= cpu_to_be32(iso->offset);
620		iso->length	= cpu_to_be32(iso->length);
621		iso->status	= cpu_to_be32(iso->status);
622		iso->actual_length = cpu_to_be32(iso->actual_length);
623	} else {
624		iso->offset	= be32_to_cpu(iso->offset);
625		iso->length	= be32_to_cpu(iso->length);
626		iso->status	= be32_to_cpu(iso->status);
627		iso->actual_length = be32_to_cpu(iso->actual_length);
628	}
629}
630
631static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
632			   struct usb_iso_packet_descriptor *uiso, int pack)
633{
634	if (pack) {
635		iso->offset		= uiso->offset;
636		iso->length		= uiso->length;
637		iso->status		= uiso->status;
638		iso->actual_length	= uiso->actual_length;
639	} else {
640		uiso->offset		= iso->offset;
641		uiso->length		= iso->length;
642		uiso->status		= iso->status;
643		uiso->actual_length	= iso->actual_length;
644	}
645}
646
647/* must free buffer */
648struct usbip_iso_packet_descriptor*
649usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
650{
651	struct usbip_iso_packet_descriptor *iso;
652	int np = urb->number_of_packets;
653	ssize_t size = np * sizeof(*iso);
654	int i;
655
656	iso = kzalloc(size, GFP_KERNEL);
657	if (!iso)
658		return NULL;
659
660	for (i = 0; i < np; i++) {
661		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
662		usbip_iso_packet_correct_endian(&iso[i], 1);
663	}
664
665	*bufflen = size;
666
667	return iso;
668}
669EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
670
671/* some members of urb must be substituted before. */
672int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
673{
674	void *buff;
675	struct usbip_iso_packet_descriptor *iso;
676	int np = urb->number_of_packets;
677	int size = np * sizeof(*iso);
678	int i;
679	int ret;
680	int total_length = 0;
681
682	if (!usb_pipeisoc(urb->pipe))
683		return 0;
684
685	/* my Bluetooth dongle gets ISO URBs which are np = 0 */
686	if (np == 0)
687		return 0;
688
689	buff = kzalloc(size, GFP_KERNEL);
690	if (!buff)
691		return -ENOMEM;
692
693	ret = usbip_recv(ud->tcp_socket, buff, size);
694	if (ret != size) {
695		dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
696			ret);
697		kfree(buff);
698
699		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
700			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
701		else
702			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
703
704		return -EPIPE;
705	}
706
707	iso = (struct usbip_iso_packet_descriptor *) buff;
708	for (i = 0; i < np; i++) {
709		usbip_iso_packet_correct_endian(&iso[i], 0);
710		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
711		total_length += urb->iso_frame_desc[i].actual_length;
712	}
713
714	kfree(buff);
715
716	if (total_length != urb->actual_length) {
717		dev_err(&urb->dev->dev,
718			"total length of iso packets %d not equal to actual length of buffer %d\n",
719			total_length, urb->actual_length);
720
721		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
722			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
723		else
724			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
725
726		return -EPIPE;
727	}
728
729	return ret;
730}
731EXPORT_SYMBOL_GPL(usbip_recv_iso);
732
733/*
734 * This functions restores the padding which was removed for optimizing
735 * the bandwidth during transfer over tcp/ip
736 *
737 * buffer and iso packets need to be stored and be in propeper endian in urb
738 * before calling this function
739 */
740void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
741{
742	int np = urb->number_of_packets;
743	int i;
744	int actualoffset = urb->actual_length;
745
746	if (!usb_pipeisoc(urb->pipe))
747		return;
748
749	/* if no packets or length of data is 0, then nothing to unpack */
750	if (np == 0 || urb->actual_length == 0)
751		return;
752
753	/*
754	 * if actual_length is transfer_buffer_length then no padding is
755	 * present.
756	 */
757	if (urb->actual_length == urb->transfer_buffer_length)
758		return;
759
760	/*
761	 * loop over all packets from last to first (to prevent overwriting
762	 * memory when padding) and move them into the proper place
763	 */
764	for (i = np-1; i > 0; i--) {
765		actualoffset -= urb->iso_frame_desc[i].actual_length;
766		memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
767			urb->transfer_buffer + actualoffset,
768			urb->iso_frame_desc[i].actual_length);
769	}
770}
771EXPORT_SYMBOL_GPL(usbip_pad_iso);
772
773/* some members of urb must be substituted before. */
774int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
775{
776	struct scatterlist *sg;
777	int ret = 0;
778	int recv;
779	int size;
780	int copy;
781	int i;
782
783	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
784		/* the direction of urb must be OUT. */
785		if (usb_pipein(urb->pipe))
786			return 0;
787
788		size = urb->transfer_buffer_length;
789	} else {
790		/* the direction of urb must be IN. */
791		if (usb_pipeout(urb->pipe))
792			return 0;
793
794		size = urb->actual_length;
795	}
796
797	/* no need to recv xbuff */
798	if (!(size > 0))
799		return 0;
800
801	if (size > urb->transfer_buffer_length)
802		/* should not happen, probably malicious packet */
803		goto error;
804
805	if (urb->num_sgs) {
806		copy = size;
807		for_each_sg(urb->sg, sg, urb->num_sgs, i) {
808			int recv_size;
809
810			if (copy < sg->length)
811				recv_size = copy;
812			else
813				recv_size = sg->length;
814
815			recv = usbip_recv(ud->tcp_socket, sg_virt(sg),
816						recv_size);
817
818			if (recv != recv_size)
819				goto error;
820
821			copy -= recv;
822			ret += recv;
823
824			if (!copy)
825				break;
826		}
827
828		if (ret != size)
829			goto error;
830	} else {
831		ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
832		if (ret != size)
833			goto error;
834	}
835
836	return ret;
837
838error:
839	dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
840	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
841		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
842	else
843		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
844
845	return -EPIPE;
846}
847EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
848
849static int __init usbip_core_init(void)
850{
851	return usbip_init_eh();
852}
853
854static void __exit usbip_core_exit(void)
855{
856	usbip_finish_eh();
857	return;
858}
859
860module_init(usbip_core_init);
861module_exit(usbip_core_exit);
862
863MODULE_AUTHOR(DRIVER_AUTHOR);
864MODULE_DESCRIPTION(DRIVER_DESC);
865MODULE_LICENSE("GPL");