xref: /openbmc/linux/drivers/usb/usbip/usbip_common.c (revision 83b975b5)
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
24 unsigned long usbip_debug_flag = 0xffffffff;
25 #else
26 unsigned long usbip_debug_flag;
27 #endif
28 EXPORT_SYMBOL_GPL(usbip_debug_flag);
29 module_param(usbip_debug_flag, ulong, S_IRUGO|S_IWUSR);
30 MODULE_PARM_DESC(usbip_debug_flag, "debug flags (defined in usbip_common.h)");
31 
32 /* FIXME */
33 struct device_attribute dev_attr_usbip_debug;
34 EXPORT_SYMBOL_GPL(dev_attr_usbip_debug);
35 
36 static 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 
42 static 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 }
50 DEVICE_ATTR_RW(usbip_debug);
51 
52 static 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 
58 static 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 
86 static 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 
136 static 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 
157 static 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 
220 void 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 }
257 EXPORT_SYMBOL_GPL(usbip_dump_urb);
258 
259 void 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 }
299 EXPORT_SYMBOL_GPL(usbip_dump_header);
300 
301 /* Receive data over TCP/IP. */
302 int 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, READ, &iov, 1, size);
313 
314 	usbip_dbg_xmit("enter\n");
315 
316 	do {
317 		sock->sk->sk_allocation = GFP_NOIO;
318 
319 		result = sock_recvmsg(sock, &msg, MSG_WAITALL);
320 		if (result <= 0)
321 			goto err;
322 
323 		total += result;
324 	} while (msg_data_left(&msg));
325 
326 	if (usbip_dbg_flag_xmit) {
327 		pr_debug("receiving....\n");
328 		usbip_dump_buffer(buf, size);
329 		pr_debug("received, osize %d ret %d size %zd total %d\n",
330 			 size, result, msg_data_left(&msg), total);
331 	}
332 
333 	return total;
334 
335 err:
336 	return result;
337 }
338 EXPORT_SYMBOL_GPL(usbip_recv);
339 
340 /* there may be more cases to tweak the flags. */
341 static unsigned int tweak_transfer_flags(unsigned int flags)
342 {
343 	flags &= ~URB_NO_TRANSFER_DMA_MAP;
344 	return flags;
345 }
346 
347 /*
348  * USBIP driver packs URB transfer flags in PDUs that are exchanged
349  * between Server (usbip_host) and Client (vhci_hcd). URB_* flags
350  * are internal to kernel and could change. Where as USBIP URB flags
351  * exchanged in PDUs are USBIP user API must not change.
352  *
353  * USBIP_URB* flags are exported as explicit API and client and server
354  * do mapping from kernel flags to USBIP_URB*. Details as follows:
355  *
356  * Client tx path (USBIP_CMD_SUBMIT):
357  * - Maps URB_* to USBIP_URB_* when it sends USBIP_CMD_SUBMIT packet.
358  *
359  * Server rx path (USBIP_CMD_SUBMIT):
360  * - Maps USBIP_URB_* to URB_* when it receives USBIP_CMD_SUBMIT packet.
361  *
362  * Flags aren't included in USBIP_CMD_UNLINK and USBIP_RET_SUBMIT packets
363  * and no special handling is needed for them in the following cases:
364  * - Server rx path (USBIP_CMD_UNLINK)
365  * - Client rx path & Server tx path (USBIP_RET_SUBMIT)
366  *
367  * Code paths:
368  * usbip_pack_pdu() is the common routine that handles packing pdu from
369  * urb and unpack pdu to an urb.
370  *
371  * usbip_pack_cmd_submit() and usbip_pack_ret_submit() handle
372  * USBIP_CMD_SUBMIT and USBIP_RET_SUBMIT respectively.
373  *
374  * usbip_map_urb_to_usbip() and usbip_map_usbip_to_urb() are used
375  * by usbip_pack_cmd_submit() and usbip_pack_ret_submit() to map
376  * flags.
377  */
378 
379 struct urb_to_usbip_flags {
380 	u32 urb_flag;
381 	u32 usbip_flag;
382 };
383 
384 #define NUM_USBIP_FLAGS	17
385 
386 static const struct urb_to_usbip_flags flag_map[NUM_USBIP_FLAGS] = {
387 	{URB_SHORT_NOT_OK, USBIP_URB_SHORT_NOT_OK},
388 	{URB_ISO_ASAP, USBIP_URB_ISO_ASAP},
389 	{URB_NO_TRANSFER_DMA_MAP, USBIP_URB_NO_TRANSFER_DMA_MAP},
390 	{URB_ZERO_PACKET, USBIP_URB_ZERO_PACKET},
391 	{URB_NO_INTERRUPT, USBIP_URB_NO_INTERRUPT},
392 	{URB_FREE_BUFFER, USBIP_URB_FREE_BUFFER},
393 	{URB_DIR_IN, USBIP_URB_DIR_IN},
394 	{URB_DIR_OUT, USBIP_URB_DIR_OUT},
395 	{URB_DIR_MASK, USBIP_URB_DIR_MASK},
396 	{URB_DMA_MAP_SINGLE, USBIP_URB_DMA_MAP_SINGLE},
397 	{URB_DMA_MAP_PAGE, USBIP_URB_DMA_MAP_PAGE},
398 	{URB_DMA_MAP_SG, USBIP_URB_DMA_MAP_SG},
399 	{URB_MAP_LOCAL, USBIP_URB_MAP_LOCAL},
400 	{URB_SETUP_MAP_SINGLE, USBIP_URB_SETUP_MAP_SINGLE},
401 	{URB_SETUP_MAP_LOCAL, USBIP_URB_SETUP_MAP_LOCAL},
402 	{URB_DMA_SG_COMBINED, USBIP_URB_DMA_SG_COMBINED},
403 	{URB_ALIGNED_TEMP_BUFFER, USBIP_URB_ALIGNED_TEMP_BUFFER},
404 };
405 
406 static unsigned int urb_to_usbip(unsigned int flags)
407 {
408 	unsigned int map_flags = 0;
409 	int loop;
410 
411 	for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) {
412 		if (flags & flag_map[loop].urb_flag)
413 			map_flags |= flag_map[loop].usbip_flag;
414 	}
415 
416 	return map_flags;
417 }
418 
419 static unsigned int usbip_to_urb(unsigned int flags)
420 {
421 	unsigned int map_flags = 0;
422 	int loop;
423 
424 	for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) {
425 		if (flags & flag_map[loop].usbip_flag)
426 			map_flags |= flag_map[loop].urb_flag;
427 	}
428 
429 	return map_flags;
430 }
431 
432 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
433 				  int pack)
434 {
435 	struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
436 
437 	/*
438 	 * Some members are not still implemented in usbip. I hope this issue
439 	 * will be discussed when usbip is ported to other operating systems.
440 	 */
441 	if (pack) {
442 		/* map after tweaking the urb flags */
443 		spdu->transfer_flags = urb_to_usbip(tweak_transfer_flags(urb->transfer_flags));
444 		spdu->transfer_buffer_length	= urb->transfer_buffer_length;
445 		spdu->start_frame		= urb->start_frame;
446 		spdu->number_of_packets		= urb->number_of_packets;
447 		spdu->interval			= urb->interval;
448 	} else  {
449 		urb->transfer_flags         = usbip_to_urb(spdu->transfer_flags);
450 		urb->transfer_buffer_length = spdu->transfer_buffer_length;
451 		urb->start_frame            = spdu->start_frame;
452 		urb->number_of_packets      = spdu->number_of_packets;
453 		urb->interval               = spdu->interval;
454 	}
455 }
456 
457 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
458 				  int pack)
459 {
460 	struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
461 
462 	if (pack) {
463 		rpdu->status		= urb->status;
464 		rpdu->actual_length	= urb->actual_length;
465 		rpdu->start_frame	= urb->start_frame;
466 		rpdu->number_of_packets = urb->number_of_packets;
467 		rpdu->error_count	= urb->error_count;
468 	} else {
469 		urb->status		= rpdu->status;
470 		urb->actual_length	= rpdu->actual_length;
471 		urb->start_frame	= rpdu->start_frame;
472 		urb->number_of_packets = rpdu->number_of_packets;
473 		urb->error_count	= rpdu->error_count;
474 	}
475 }
476 
477 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
478 		    int pack)
479 {
480 	switch (cmd) {
481 	case USBIP_CMD_SUBMIT:
482 		usbip_pack_cmd_submit(pdu, urb, pack);
483 		break;
484 	case USBIP_RET_SUBMIT:
485 		usbip_pack_ret_submit(pdu, urb, pack);
486 		break;
487 	default:
488 		/* NOT REACHED */
489 		pr_err("unknown command\n");
490 		break;
491 	}
492 }
493 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
494 
495 static void correct_endian_basic(struct usbip_header_basic *base, int send)
496 {
497 	if (send) {
498 		base->command	= cpu_to_be32(base->command);
499 		base->seqnum	= cpu_to_be32(base->seqnum);
500 		base->devid	= cpu_to_be32(base->devid);
501 		base->direction	= cpu_to_be32(base->direction);
502 		base->ep	= cpu_to_be32(base->ep);
503 	} else {
504 		base->command	= be32_to_cpu(base->command);
505 		base->seqnum	= be32_to_cpu(base->seqnum);
506 		base->devid	= be32_to_cpu(base->devid);
507 		base->direction	= be32_to_cpu(base->direction);
508 		base->ep	= be32_to_cpu(base->ep);
509 	}
510 }
511 
512 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
513 				      int send)
514 {
515 	if (send) {
516 		pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
517 
518 		cpu_to_be32s(&pdu->transfer_buffer_length);
519 		cpu_to_be32s(&pdu->start_frame);
520 		cpu_to_be32s(&pdu->number_of_packets);
521 		cpu_to_be32s(&pdu->interval);
522 	} else {
523 		pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
524 
525 		be32_to_cpus(&pdu->transfer_buffer_length);
526 		be32_to_cpus(&pdu->start_frame);
527 		be32_to_cpus(&pdu->number_of_packets);
528 		be32_to_cpus(&pdu->interval);
529 	}
530 }
531 
532 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
533 				      int send)
534 {
535 	if (send) {
536 		cpu_to_be32s(&pdu->status);
537 		cpu_to_be32s(&pdu->actual_length);
538 		cpu_to_be32s(&pdu->start_frame);
539 		cpu_to_be32s(&pdu->number_of_packets);
540 		cpu_to_be32s(&pdu->error_count);
541 	} else {
542 		be32_to_cpus(&pdu->status);
543 		be32_to_cpus(&pdu->actual_length);
544 		be32_to_cpus(&pdu->start_frame);
545 		be32_to_cpus(&pdu->number_of_packets);
546 		be32_to_cpus(&pdu->error_count);
547 	}
548 }
549 
550 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
551 				      int send)
552 {
553 	if (send)
554 		pdu->seqnum = cpu_to_be32(pdu->seqnum);
555 	else
556 		pdu->seqnum = be32_to_cpu(pdu->seqnum);
557 }
558 
559 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
560 				      int send)
561 {
562 	if (send)
563 		cpu_to_be32s(&pdu->status);
564 	else
565 		be32_to_cpus(&pdu->status);
566 }
567 
568 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
569 {
570 	__u32 cmd = 0;
571 
572 	if (send)
573 		cmd = pdu->base.command;
574 
575 	correct_endian_basic(&pdu->base, send);
576 
577 	if (!send)
578 		cmd = pdu->base.command;
579 
580 	switch (cmd) {
581 	case USBIP_CMD_SUBMIT:
582 		correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
583 		break;
584 	case USBIP_RET_SUBMIT:
585 		correct_endian_ret_submit(&pdu->u.ret_submit, send);
586 		break;
587 	case USBIP_CMD_UNLINK:
588 		correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
589 		break;
590 	case USBIP_RET_UNLINK:
591 		correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
592 		break;
593 	default:
594 		/* NOT REACHED */
595 		pr_err("unknown command\n");
596 		break;
597 	}
598 }
599 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
600 
601 static void usbip_iso_packet_correct_endian(
602 		struct usbip_iso_packet_descriptor *iso, int send)
603 {
604 	/* does not need all members. but copy all simply. */
605 	if (send) {
606 		iso->offset	= cpu_to_be32(iso->offset);
607 		iso->length	= cpu_to_be32(iso->length);
608 		iso->status	= cpu_to_be32(iso->status);
609 		iso->actual_length = cpu_to_be32(iso->actual_length);
610 	} else {
611 		iso->offset	= be32_to_cpu(iso->offset);
612 		iso->length	= be32_to_cpu(iso->length);
613 		iso->status	= be32_to_cpu(iso->status);
614 		iso->actual_length = be32_to_cpu(iso->actual_length);
615 	}
616 }
617 
618 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
619 			   struct usb_iso_packet_descriptor *uiso, int pack)
620 {
621 	if (pack) {
622 		iso->offset		= uiso->offset;
623 		iso->length		= uiso->length;
624 		iso->status		= uiso->status;
625 		iso->actual_length	= uiso->actual_length;
626 	} else {
627 		uiso->offset		= iso->offset;
628 		uiso->length		= iso->length;
629 		uiso->status		= iso->status;
630 		uiso->actual_length	= iso->actual_length;
631 	}
632 }
633 
634 /* must free buffer */
635 struct usbip_iso_packet_descriptor*
636 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
637 {
638 	struct usbip_iso_packet_descriptor *iso;
639 	int np = urb->number_of_packets;
640 	ssize_t size = np * sizeof(*iso);
641 	int i;
642 
643 	iso = kzalloc(size, GFP_KERNEL);
644 	if (!iso)
645 		return NULL;
646 
647 	for (i = 0; i < np; i++) {
648 		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
649 		usbip_iso_packet_correct_endian(&iso[i], 1);
650 	}
651 
652 	*bufflen = size;
653 
654 	return iso;
655 }
656 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
657 
658 /* some members of urb must be substituted before. */
659 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
660 {
661 	void *buff;
662 	struct usbip_iso_packet_descriptor *iso;
663 	int np = urb->number_of_packets;
664 	int size = np * sizeof(*iso);
665 	int i;
666 	int ret;
667 	int total_length = 0;
668 
669 	if (!usb_pipeisoc(urb->pipe))
670 		return 0;
671 
672 	/* my Bluetooth dongle gets ISO URBs which are np = 0 */
673 	if (np == 0)
674 		return 0;
675 
676 	buff = kzalloc(size, GFP_KERNEL);
677 	if (!buff)
678 		return -ENOMEM;
679 
680 	ret = usbip_recv(ud->tcp_socket, buff, size);
681 	if (ret != size) {
682 		dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
683 			ret);
684 		kfree(buff);
685 
686 		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
687 			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
688 		else
689 			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
690 
691 		return -EPIPE;
692 	}
693 
694 	iso = (struct usbip_iso_packet_descriptor *) buff;
695 	for (i = 0; i < np; i++) {
696 		usbip_iso_packet_correct_endian(&iso[i], 0);
697 		usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
698 		total_length += urb->iso_frame_desc[i].actual_length;
699 	}
700 
701 	kfree(buff);
702 
703 	if (total_length != urb->actual_length) {
704 		dev_err(&urb->dev->dev,
705 			"total length of iso packets %d not equal to actual length of buffer %d\n",
706 			total_length, urb->actual_length);
707 
708 		if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
709 			usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
710 		else
711 			usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
712 
713 		return -EPIPE;
714 	}
715 
716 	return ret;
717 }
718 EXPORT_SYMBOL_GPL(usbip_recv_iso);
719 
720 /*
721  * This functions restores the padding which was removed for optimizing
722  * the bandwidth during transfer over tcp/ip
723  *
724  * buffer and iso packets need to be stored and be in propeper endian in urb
725  * before calling this function
726  */
727 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
728 {
729 	int np = urb->number_of_packets;
730 	int i;
731 	int actualoffset = urb->actual_length;
732 
733 	if (!usb_pipeisoc(urb->pipe))
734 		return;
735 
736 	/* if no packets or length of data is 0, then nothing to unpack */
737 	if (np == 0 || urb->actual_length == 0)
738 		return;
739 
740 	/*
741 	 * if actual_length is transfer_buffer_length then no padding is
742 	 * present.
743 	 */
744 	if (urb->actual_length == urb->transfer_buffer_length)
745 		return;
746 
747 	/*
748 	 * loop over all packets from last to first (to prevent overwriting
749 	 * memory when padding) and move them into the proper place
750 	 */
751 	for (i = np-1; i > 0; i--) {
752 		actualoffset -= urb->iso_frame_desc[i].actual_length;
753 		memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
754 			urb->transfer_buffer + actualoffset,
755 			urb->iso_frame_desc[i].actual_length);
756 	}
757 }
758 EXPORT_SYMBOL_GPL(usbip_pad_iso);
759 
760 /* some members of urb must be substituted before. */
761 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
762 {
763 	struct scatterlist *sg;
764 	int ret = 0;
765 	int recv;
766 	int size;
767 	int copy;
768 	int i;
769 
770 	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
771 		/* the direction of urb must be OUT. */
772 		if (usb_pipein(urb->pipe))
773 			return 0;
774 
775 		size = urb->transfer_buffer_length;
776 	} else {
777 		/* the direction of urb must be IN. */
778 		if (usb_pipeout(urb->pipe))
779 			return 0;
780 
781 		size = urb->actual_length;
782 	}
783 
784 	/* no need to recv xbuff */
785 	if (!(size > 0))
786 		return 0;
787 
788 	if (size > urb->transfer_buffer_length)
789 		/* should not happen, probably malicious packet */
790 		goto error;
791 
792 	if (urb->num_sgs) {
793 		copy = size;
794 		for_each_sg(urb->sg, sg, urb->num_sgs, i) {
795 			int recv_size;
796 
797 			if (copy < sg->length)
798 				recv_size = copy;
799 			else
800 				recv_size = sg->length;
801 
802 			recv = usbip_recv(ud->tcp_socket, sg_virt(sg),
803 						recv_size);
804 
805 			if (recv != recv_size)
806 				goto error;
807 
808 			copy -= recv;
809 			ret += recv;
810 
811 			if (!copy)
812 				break;
813 		}
814 
815 		if (ret != size)
816 			goto error;
817 	} else {
818 		ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
819 		if (ret != size)
820 			goto error;
821 	}
822 
823 	return ret;
824 
825 error:
826 	dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
827 	if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
828 		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
829 	else
830 		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
831 
832 	return -EPIPE;
833 }
834 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
835 
836 static int __init usbip_core_init(void)
837 {
838 	return usbip_init_eh();
839 }
840 
841 static void __exit usbip_core_exit(void)
842 {
843 	usbip_finish_eh();
844 	return;
845 }
846 
847 module_init(usbip_core_init);
848 module_exit(usbip_core_exit);
849 
850 MODULE_AUTHOR(DRIVER_AUTHOR);
851 MODULE_DESCRIPTION(DRIVER_DESC);
852 MODULE_LICENSE("GPL");
853