1 /* Target based USB-Gadget
2  *
3  * UAS protocol handling, target callbacks, configfs handling,
4  * BBB (USB Mass Storage Class Bulk-Only (BBB) and Transport protocol handling.
5  *
6  * Author: Sebastian Andrzej Siewior <bigeasy at linutronix dot de>
7  * License: GPLv2 as published by FSF.
8  */
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/string.h>
13 #include <linux/configfs.h>
14 #include <linux/ctype.h>
15 #include <linux/usb/ch9.h>
16 #include <linux/usb/composite.h>
17 #include <linux/usb/gadget.h>
18 #include <linux/usb/storage.h>
19 #include <scsi/scsi.h>
20 #include <scsi/scsi_tcq.h>
21 #include <target/target_core_base.h>
22 #include <target/target_core_fabric.h>
23 #include <target/target_core_fabric_configfs.h>
24 #include <target/target_core_configfs.h>
25 #include <target/configfs_macros.h>
26 #include <asm/unaligned.h>
27 
28 #include "tcm_usb_gadget.h"
29 
30 USB_GADGET_COMPOSITE_OPTIONS();
31 
32 static const struct target_core_fabric_ops usbg_ops;
33 
34 static inline struct f_uas *to_f_uas(struct usb_function *f)
35 {
36 	return container_of(f, struct f_uas, function);
37 }
38 
39 static void usbg_cmd_release(struct kref *);
40 
41 static inline void usbg_cleanup_cmd(struct usbg_cmd *cmd)
42 {
43 	kref_put(&cmd->ref, usbg_cmd_release);
44 }
45 
46 /* Start bot.c code */
47 
48 static int bot_enqueue_cmd_cbw(struct f_uas *fu)
49 {
50 	int ret;
51 
52 	if (fu->flags & USBG_BOT_CMD_PEND)
53 		return 0;
54 
55 	ret = usb_ep_queue(fu->ep_out, fu->cmd.req, GFP_ATOMIC);
56 	if (!ret)
57 		fu->flags |= USBG_BOT_CMD_PEND;
58 	return ret;
59 }
60 
61 static void bot_status_complete(struct usb_ep *ep, struct usb_request *req)
62 {
63 	struct usbg_cmd *cmd = req->context;
64 	struct f_uas *fu = cmd->fu;
65 
66 	usbg_cleanup_cmd(cmd);
67 	if (req->status < 0) {
68 		pr_err("ERR %s(%d)\n", __func__, __LINE__);
69 		return;
70 	}
71 
72 	/* CSW completed, wait for next CBW */
73 	bot_enqueue_cmd_cbw(fu);
74 }
75 
76 static void bot_enqueue_sense_code(struct f_uas *fu, struct usbg_cmd *cmd)
77 {
78 	struct bulk_cs_wrap *csw = &fu->bot_status.csw;
79 	int ret;
80 	u8 *sense;
81 	unsigned int csw_stat;
82 
83 	csw_stat = cmd->csw_code;
84 
85 	/*
86 	 * We can't send SENSE as a response. So we take ASC & ASCQ from our
87 	 * sense buffer and queue it and hope the host sends a REQUEST_SENSE
88 	 * command where it learns why we failed.
89 	 */
90 	sense = cmd->sense_iu.sense;
91 
92 	csw->Tag = cmd->bot_tag;
93 	csw->Status = csw_stat;
94 	fu->bot_status.req->context = cmd;
95 	ret = usb_ep_queue(fu->ep_in, fu->bot_status.req, GFP_ATOMIC);
96 	if (ret)
97 		pr_err("%s(%d) ERR: %d\n", __func__, __LINE__, ret);
98 }
99 
100 static void bot_err_compl(struct usb_ep *ep, struct usb_request *req)
101 {
102 	struct usbg_cmd *cmd = req->context;
103 	struct f_uas *fu = cmd->fu;
104 
105 	if (req->status < 0)
106 		pr_err("ERR %s(%d)\n", __func__, __LINE__);
107 
108 	if (cmd->data_len) {
109 		if (cmd->data_len > ep->maxpacket) {
110 			req->length = ep->maxpacket;
111 			cmd->data_len -= ep->maxpacket;
112 		} else {
113 			req->length = cmd->data_len;
114 			cmd->data_len = 0;
115 		}
116 
117 		usb_ep_queue(ep, req, GFP_ATOMIC);
118 		return ;
119 	}
120 	bot_enqueue_sense_code(fu, cmd);
121 }
122 
123 static void bot_send_bad_status(struct usbg_cmd *cmd)
124 {
125 	struct f_uas *fu = cmd->fu;
126 	struct bulk_cs_wrap *csw = &fu->bot_status.csw;
127 	struct usb_request *req;
128 	struct usb_ep *ep;
129 
130 	csw->Residue = cpu_to_le32(cmd->data_len);
131 
132 	if (cmd->data_len) {
133 		if (cmd->is_read) {
134 			ep = fu->ep_in;
135 			req = fu->bot_req_in;
136 		} else {
137 			ep = fu->ep_out;
138 			req = fu->bot_req_out;
139 		}
140 
141 		if (cmd->data_len > fu->ep_in->maxpacket) {
142 			req->length = ep->maxpacket;
143 			cmd->data_len -= ep->maxpacket;
144 		} else {
145 			req->length = cmd->data_len;
146 			cmd->data_len = 0;
147 		}
148 		req->complete = bot_err_compl;
149 		req->context = cmd;
150 		req->buf = fu->cmd.buf;
151 		usb_ep_queue(ep, req, GFP_KERNEL);
152 	} else {
153 		bot_enqueue_sense_code(fu, cmd);
154 	}
155 }
156 
157 static int bot_send_status(struct usbg_cmd *cmd, bool moved_data)
158 {
159 	struct f_uas *fu = cmd->fu;
160 	struct bulk_cs_wrap *csw = &fu->bot_status.csw;
161 	int ret;
162 
163 	if (cmd->se_cmd.scsi_status == SAM_STAT_GOOD) {
164 		if (!moved_data && cmd->data_len) {
165 			/*
166 			 * the host wants to move data, we don't. Fill / empty
167 			 * the pipe and then send the csw with reside set.
168 			 */
169 			cmd->csw_code = US_BULK_STAT_OK;
170 			bot_send_bad_status(cmd);
171 			return 0;
172 		}
173 
174 		csw->Tag = cmd->bot_tag;
175 		csw->Residue = cpu_to_le32(0);
176 		csw->Status = US_BULK_STAT_OK;
177 		fu->bot_status.req->context = cmd;
178 
179 		ret = usb_ep_queue(fu->ep_in, fu->bot_status.req, GFP_KERNEL);
180 		if (ret)
181 			pr_err("%s(%d) ERR: %d\n", __func__, __LINE__, ret);
182 	} else {
183 		cmd->csw_code = US_BULK_STAT_FAIL;
184 		bot_send_bad_status(cmd);
185 	}
186 	return 0;
187 }
188 
189 /*
190  * Called after command (no data transfer) or after the write (to device)
191  * operation is completed
192  */
193 static int bot_send_status_response(struct usbg_cmd *cmd)
194 {
195 	bool moved_data = false;
196 
197 	if (!cmd->is_read)
198 		moved_data = true;
199 	return bot_send_status(cmd, moved_data);
200 }
201 
202 /* Read request completed, now we have to send the CSW */
203 static void bot_read_compl(struct usb_ep *ep, struct usb_request *req)
204 {
205 	struct usbg_cmd *cmd = req->context;
206 
207 	if (req->status < 0)
208 		pr_err("ERR %s(%d)\n", __func__, __LINE__);
209 
210 	bot_send_status(cmd, true);
211 }
212 
213 static int bot_send_read_response(struct usbg_cmd *cmd)
214 {
215 	struct f_uas *fu = cmd->fu;
216 	struct se_cmd *se_cmd = &cmd->se_cmd;
217 	struct usb_gadget *gadget = fuas_to_gadget(fu);
218 	int ret;
219 
220 	if (!cmd->data_len) {
221 		cmd->csw_code = US_BULK_STAT_PHASE;
222 		bot_send_bad_status(cmd);
223 		return 0;
224 	}
225 
226 	if (!gadget->sg_supported) {
227 		cmd->data_buf = kmalloc(se_cmd->data_length, GFP_ATOMIC);
228 		if (!cmd->data_buf)
229 			return -ENOMEM;
230 
231 		sg_copy_to_buffer(se_cmd->t_data_sg,
232 				se_cmd->t_data_nents,
233 				cmd->data_buf,
234 				se_cmd->data_length);
235 
236 		fu->bot_req_in->buf = cmd->data_buf;
237 	} else {
238 		fu->bot_req_in->buf = NULL;
239 		fu->bot_req_in->num_sgs = se_cmd->t_data_nents;
240 		fu->bot_req_in->sg = se_cmd->t_data_sg;
241 	}
242 
243 	fu->bot_req_in->complete = bot_read_compl;
244 	fu->bot_req_in->length = se_cmd->data_length;
245 	fu->bot_req_in->context = cmd;
246 	ret = usb_ep_queue(fu->ep_in, fu->bot_req_in, GFP_ATOMIC);
247 	if (ret)
248 		pr_err("%s(%d)\n", __func__, __LINE__);
249 	return 0;
250 }
251 
252 static void usbg_data_write_cmpl(struct usb_ep *, struct usb_request *);
253 static int usbg_prepare_w_request(struct usbg_cmd *, struct usb_request *);
254 
255 static int bot_send_write_request(struct usbg_cmd *cmd)
256 {
257 	struct f_uas *fu = cmd->fu;
258 	struct se_cmd *se_cmd = &cmd->se_cmd;
259 	struct usb_gadget *gadget = fuas_to_gadget(fu);
260 	int ret;
261 
262 	init_completion(&cmd->write_complete);
263 	cmd->fu = fu;
264 
265 	if (!cmd->data_len) {
266 		cmd->csw_code = US_BULK_STAT_PHASE;
267 		return -EINVAL;
268 	}
269 
270 	if (!gadget->sg_supported) {
271 		cmd->data_buf = kmalloc(se_cmd->data_length, GFP_KERNEL);
272 		if (!cmd->data_buf)
273 			return -ENOMEM;
274 
275 		fu->bot_req_out->buf = cmd->data_buf;
276 	} else {
277 		fu->bot_req_out->buf = NULL;
278 		fu->bot_req_out->num_sgs = se_cmd->t_data_nents;
279 		fu->bot_req_out->sg = se_cmd->t_data_sg;
280 	}
281 
282 	fu->bot_req_out->complete = usbg_data_write_cmpl;
283 	fu->bot_req_out->length = se_cmd->data_length;
284 	fu->bot_req_out->context = cmd;
285 
286 	ret = usbg_prepare_w_request(cmd, fu->bot_req_out);
287 	if (ret)
288 		goto cleanup;
289 	ret = usb_ep_queue(fu->ep_out, fu->bot_req_out, GFP_KERNEL);
290 	if (ret)
291 		pr_err("%s(%d)\n", __func__, __LINE__);
292 
293 	wait_for_completion(&cmd->write_complete);
294 	target_execute_cmd(se_cmd);
295 cleanup:
296 	return ret;
297 }
298 
299 static int bot_submit_command(struct f_uas *, void *, unsigned int);
300 
301 static void bot_cmd_complete(struct usb_ep *ep, struct usb_request *req)
302 {
303 	struct f_uas *fu = req->context;
304 	int ret;
305 
306 	fu->flags &= ~USBG_BOT_CMD_PEND;
307 
308 	if (req->status < 0)
309 		return;
310 
311 	ret = bot_submit_command(fu, req->buf, req->actual);
312 	if (ret)
313 		pr_err("%s(%d): %d\n", __func__, __LINE__, ret);
314 }
315 
316 static int bot_prepare_reqs(struct f_uas *fu)
317 {
318 	int ret;
319 
320 	fu->bot_req_in = usb_ep_alloc_request(fu->ep_in, GFP_KERNEL);
321 	if (!fu->bot_req_in)
322 		goto err;
323 
324 	fu->bot_req_out = usb_ep_alloc_request(fu->ep_out, GFP_KERNEL);
325 	if (!fu->bot_req_out)
326 		goto err_out;
327 
328 	fu->cmd.req = usb_ep_alloc_request(fu->ep_out, GFP_KERNEL);
329 	if (!fu->cmd.req)
330 		goto err_cmd;
331 
332 	fu->bot_status.req = usb_ep_alloc_request(fu->ep_in, GFP_KERNEL);
333 	if (!fu->bot_status.req)
334 		goto err_sts;
335 
336 	fu->bot_status.req->buf = &fu->bot_status.csw;
337 	fu->bot_status.req->length = US_BULK_CS_WRAP_LEN;
338 	fu->bot_status.req->complete = bot_status_complete;
339 	fu->bot_status.csw.Signature = cpu_to_le32(US_BULK_CS_SIGN);
340 
341 	fu->cmd.buf = kmalloc(fu->ep_out->maxpacket, GFP_KERNEL);
342 	if (!fu->cmd.buf)
343 		goto err_buf;
344 
345 	fu->cmd.req->complete = bot_cmd_complete;
346 	fu->cmd.req->buf = fu->cmd.buf;
347 	fu->cmd.req->length = fu->ep_out->maxpacket;
348 	fu->cmd.req->context = fu;
349 
350 	ret = bot_enqueue_cmd_cbw(fu);
351 	if (ret)
352 		goto err_queue;
353 	return 0;
354 err_queue:
355 	kfree(fu->cmd.buf);
356 	fu->cmd.buf = NULL;
357 err_buf:
358 	usb_ep_free_request(fu->ep_in, fu->bot_status.req);
359 err_sts:
360 	usb_ep_free_request(fu->ep_out, fu->cmd.req);
361 	fu->cmd.req = NULL;
362 err_cmd:
363 	usb_ep_free_request(fu->ep_out, fu->bot_req_out);
364 	fu->bot_req_out = NULL;
365 err_out:
366 	usb_ep_free_request(fu->ep_in, fu->bot_req_in);
367 	fu->bot_req_in = NULL;
368 err:
369 	pr_err("BOT: endpoint setup failed\n");
370 	return -ENOMEM;
371 }
372 
373 static void bot_cleanup_old_alt(struct f_uas *fu)
374 {
375 	if (!(fu->flags & USBG_ENABLED))
376 		return;
377 
378 	usb_ep_disable(fu->ep_in);
379 	usb_ep_disable(fu->ep_out);
380 
381 	if (!fu->bot_req_in)
382 		return;
383 
384 	usb_ep_free_request(fu->ep_in, fu->bot_req_in);
385 	usb_ep_free_request(fu->ep_out, fu->bot_req_out);
386 	usb_ep_free_request(fu->ep_out, fu->cmd.req);
387 	usb_ep_free_request(fu->ep_out, fu->bot_status.req);
388 
389 	kfree(fu->cmd.buf);
390 
391 	fu->bot_req_in = NULL;
392 	fu->bot_req_out = NULL;
393 	fu->cmd.req = NULL;
394 	fu->bot_status.req = NULL;
395 	fu->cmd.buf = NULL;
396 }
397 
398 static void bot_set_alt(struct f_uas *fu)
399 {
400 	struct usb_function *f = &fu->function;
401 	struct usb_gadget *gadget = f->config->cdev->gadget;
402 	int ret;
403 
404 	fu->flags = USBG_IS_BOT;
405 
406 	config_ep_by_speed(gadget, f, fu->ep_in);
407 	ret = usb_ep_enable(fu->ep_in);
408 	if (ret)
409 		goto err_b_in;
410 
411 	config_ep_by_speed(gadget, f, fu->ep_out);
412 	ret = usb_ep_enable(fu->ep_out);
413 	if (ret)
414 		goto err_b_out;
415 
416 	ret = bot_prepare_reqs(fu);
417 	if (ret)
418 		goto err_wq;
419 	fu->flags |= USBG_ENABLED;
420 	pr_info("Using the BOT protocol\n");
421 	return;
422 err_wq:
423 	usb_ep_disable(fu->ep_out);
424 err_b_out:
425 	usb_ep_disable(fu->ep_in);
426 err_b_in:
427 	fu->flags = USBG_IS_BOT;
428 }
429 
430 static int usbg_bot_setup(struct usb_function *f,
431 		const struct usb_ctrlrequest *ctrl)
432 {
433 	struct f_uas *fu = to_f_uas(f);
434 	struct usb_composite_dev *cdev = f->config->cdev;
435 	u16 w_value = le16_to_cpu(ctrl->wValue);
436 	u16 w_length = le16_to_cpu(ctrl->wLength);
437 	int luns;
438 	u8 *ret_lun;
439 
440 	switch (ctrl->bRequest) {
441 	case US_BULK_GET_MAX_LUN:
442 		if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_CLASS |
443 					USB_RECIP_INTERFACE))
444 			return -ENOTSUPP;
445 
446 		if (w_length < 1)
447 			return -EINVAL;
448 		if (w_value != 0)
449 			return -EINVAL;
450 		luns = atomic_read(&fu->tpg->tpg_port_count);
451 		if (!luns) {
452 			pr_err("No LUNs configured?\n");
453 			return -EINVAL;
454 		}
455 		/*
456 		 * If 4 LUNs are present we return 3 i.e. LUN 0..3 can be
457 		 * accessed. The upper limit is 0xf
458 		 */
459 		luns--;
460 		if (luns > 0xf) {
461 			pr_info_once("Limiting the number of luns to 16\n");
462 			luns = 0xf;
463 		}
464 		ret_lun = cdev->req->buf;
465 		*ret_lun = luns;
466 		cdev->req->length = 1;
467 		return usb_ep_queue(cdev->gadget->ep0, cdev->req, GFP_ATOMIC);
468 		break;
469 
470 	case US_BULK_RESET_REQUEST:
471 		/* XXX maybe we should remove previous requests for IN + OUT */
472 		bot_enqueue_cmd_cbw(fu);
473 		return 0;
474 		break;
475 	}
476 	return -ENOTSUPP;
477 }
478 
479 /* Start uas.c code */
480 
481 static void uasp_cleanup_one_stream(struct f_uas *fu, struct uas_stream *stream)
482 {
483 	/* We have either all three allocated or none */
484 	if (!stream->req_in)
485 		return;
486 
487 	usb_ep_free_request(fu->ep_in, stream->req_in);
488 	usb_ep_free_request(fu->ep_out, stream->req_out);
489 	usb_ep_free_request(fu->ep_status, stream->req_status);
490 
491 	stream->req_in = NULL;
492 	stream->req_out = NULL;
493 	stream->req_status = NULL;
494 }
495 
496 static void uasp_free_cmdreq(struct f_uas *fu)
497 {
498 	usb_ep_free_request(fu->ep_cmd, fu->cmd.req);
499 	kfree(fu->cmd.buf);
500 	fu->cmd.req = NULL;
501 	fu->cmd.buf = NULL;
502 }
503 
504 static void uasp_cleanup_old_alt(struct f_uas *fu)
505 {
506 	int i;
507 
508 	if (!(fu->flags & USBG_ENABLED))
509 		return;
510 
511 	usb_ep_disable(fu->ep_in);
512 	usb_ep_disable(fu->ep_out);
513 	usb_ep_disable(fu->ep_status);
514 	usb_ep_disable(fu->ep_cmd);
515 
516 	for (i = 0; i < UASP_SS_EP_COMP_NUM_STREAMS; i++)
517 		uasp_cleanup_one_stream(fu, &fu->stream[i]);
518 	uasp_free_cmdreq(fu);
519 }
520 
521 static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req);
522 
523 static int uasp_prepare_r_request(struct usbg_cmd *cmd)
524 {
525 	struct se_cmd *se_cmd = &cmd->se_cmd;
526 	struct f_uas *fu = cmd->fu;
527 	struct usb_gadget *gadget = fuas_to_gadget(fu);
528 	struct uas_stream *stream = cmd->stream;
529 
530 	if (!gadget->sg_supported) {
531 		cmd->data_buf = kmalloc(se_cmd->data_length, GFP_ATOMIC);
532 		if (!cmd->data_buf)
533 			return -ENOMEM;
534 
535 		sg_copy_to_buffer(se_cmd->t_data_sg,
536 				se_cmd->t_data_nents,
537 				cmd->data_buf,
538 				se_cmd->data_length);
539 
540 		stream->req_in->buf = cmd->data_buf;
541 	} else {
542 		stream->req_in->buf = NULL;
543 		stream->req_in->num_sgs = se_cmd->t_data_nents;
544 		stream->req_in->sg = se_cmd->t_data_sg;
545 	}
546 
547 	stream->req_in->complete = uasp_status_data_cmpl;
548 	stream->req_in->length = se_cmd->data_length;
549 	stream->req_in->context = cmd;
550 
551 	cmd->state = UASP_SEND_STATUS;
552 	return 0;
553 }
554 
555 static void uasp_prepare_status(struct usbg_cmd *cmd)
556 {
557 	struct se_cmd *se_cmd = &cmd->se_cmd;
558 	struct sense_iu *iu = &cmd->sense_iu;
559 	struct uas_stream *stream = cmd->stream;
560 
561 	cmd->state = UASP_QUEUE_COMMAND;
562 	iu->iu_id = IU_ID_STATUS;
563 	iu->tag = cpu_to_be16(cmd->tag);
564 
565 	/*
566 	 * iu->status_qual = cpu_to_be16(STATUS QUALIFIER SAM-4. Where R U?);
567 	 */
568 	iu->len = cpu_to_be16(se_cmd->scsi_sense_length);
569 	iu->status = se_cmd->scsi_status;
570 	stream->req_status->context = cmd;
571 	stream->req_status->length = se_cmd->scsi_sense_length + 16;
572 	stream->req_status->buf = iu;
573 	stream->req_status->complete = uasp_status_data_cmpl;
574 }
575 
576 static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req)
577 {
578 	struct usbg_cmd *cmd = req->context;
579 	struct uas_stream *stream = cmd->stream;
580 	struct f_uas *fu = cmd->fu;
581 	int ret;
582 
583 	if (req->status < 0)
584 		goto cleanup;
585 
586 	switch (cmd->state) {
587 	case UASP_SEND_DATA:
588 		ret = uasp_prepare_r_request(cmd);
589 		if (ret)
590 			goto cleanup;
591 		ret = usb_ep_queue(fu->ep_in, stream->req_in, GFP_ATOMIC);
592 		if (ret)
593 			pr_err("%s(%d) => %d\n", __func__, __LINE__, ret);
594 		break;
595 
596 	case UASP_RECEIVE_DATA:
597 		ret = usbg_prepare_w_request(cmd, stream->req_out);
598 		if (ret)
599 			goto cleanup;
600 		ret = usb_ep_queue(fu->ep_out, stream->req_out, GFP_ATOMIC);
601 		if (ret)
602 			pr_err("%s(%d) => %d\n", __func__, __LINE__, ret);
603 		break;
604 
605 	case UASP_SEND_STATUS:
606 		uasp_prepare_status(cmd);
607 		ret = usb_ep_queue(fu->ep_status, stream->req_status,
608 				GFP_ATOMIC);
609 		if (ret)
610 			pr_err("%s(%d) => %d\n", __func__, __LINE__, ret);
611 		break;
612 
613 	case UASP_QUEUE_COMMAND:
614 		usbg_cleanup_cmd(cmd);
615 		usb_ep_queue(fu->ep_cmd, fu->cmd.req, GFP_ATOMIC);
616 		break;
617 
618 	default:
619 		BUG();
620 	}
621 	return;
622 
623 cleanup:
624 	usbg_cleanup_cmd(cmd);
625 }
626 
627 static int uasp_send_status_response(struct usbg_cmd *cmd)
628 {
629 	struct f_uas *fu = cmd->fu;
630 	struct uas_stream *stream = cmd->stream;
631 	struct sense_iu *iu = &cmd->sense_iu;
632 
633 	iu->tag = cpu_to_be16(cmd->tag);
634 	stream->req_status->complete = uasp_status_data_cmpl;
635 	stream->req_status->context = cmd;
636 	cmd->fu = fu;
637 	uasp_prepare_status(cmd);
638 	return usb_ep_queue(fu->ep_status, stream->req_status, GFP_ATOMIC);
639 }
640 
641 static int uasp_send_read_response(struct usbg_cmd *cmd)
642 {
643 	struct f_uas *fu = cmd->fu;
644 	struct uas_stream *stream = cmd->stream;
645 	struct sense_iu *iu = &cmd->sense_iu;
646 	int ret;
647 
648 	cmd->fu = fu;
649 
650 	iu->tag = cpu_to_be16(cmd->tag);
651 	if (fu->flags & USBG_USE_STREAMS) {
652 
653 		ret = uasp_prepare_r_request(cmd);
654 		if (ret)
655 			goto out;
656 		ret = usb_ep_queue(fu->ep_in, stream->req_in, GFP_ATOMIC);
657 		if (ret) {
658 			pr_err("%s(%d) => %d\n", __func__, __LINE__, ret);
659 			kfree(cmd->data_buf);
660 			cmd->data_buf = NULL;
661 		}
662 
663 	} else {
664 
665 		iu->iu_id = IU_ID_READ_READY;
666 		iu->tag = cpu_to_be16(cmd->tag);
667 
668 		stream->req_status->complete = uasp_status_data_cmpl;
669 		stream->req_status->context = cmd;
670 
671 		cmd->state = UASP_SEND_DATA;
672 		stream->req_status->buf = iu;
673 		stream->req_status->length = sizeof(struct iu);
674 
675 		ret = usb_ep_queue(fu->ep_status, stream->req_status,
676 				GFP_ATOMIC);
677 		if (ret)
678 			pr_err("%s(%d) => %d\n", __func__, __LINE__, ret);
679 	}
680 out:
681 	return ret;
682 }
683 
684 static int uasp_send_write_request(struct usbg_cmd *cmd)
685 {
686 	struct f_uas *fu = cmd->fu;
687 	struct se_cmd *se_cmd = &cmd->se_cmd;
688 	struct uas_stream *stream = cmd->stream;
689 	struct sense_iu *iu = &cmd->sense_iu;
690 	int ret;
691 
692 	init_completion(&cmd->write_complete);
693 	cmd->fu = fu;
694 
695 	iu->tag = cpu_to_be16(cmd->tag);
696 
697 	if (fu->flags & USBG_USE_STREAMS) {
698 
699 		ret = usbg_prepare_w_request(cmd, stream->req_out);
700 		if (ret)
701 			goto cleanup;
702 		ret = usb_ep_queue(fu->ep_out, stream->req_out, GFP_ATOMIC);
703 		if (ret)
704 			pr_err("%s(%d)\n", __func__, __LINE__);
705 
706 	} else {
707 
708 		iu->iu_id = IU_ID_WRITE_READY;
709 		iu->tag = cpu_to_be16(cmd->tag);
710 
711 		stream->req_status->complete = uasp_status_data_cmpl;
712 		stream->req_status->context = cmd;
713 
714 		cmd->state = UASP_RECEIVE_DATA;
715 		stream->req_status->buf = iu;
716 		stream->req_status->length = sizeof(struct iu);
717 
718 		ret = usb_ep_queue(fu->ep_status, stream->req_status,
719 				GFP_ATOMIC);
720 		if (ret)
721 			pr_err("%s(%d)\n", __func__, __LINE__);
722 	}
723 
724 	wait_for_completion(&cmd->write_complete);
725 	target_execute_cmd(se_cmd);
726 cleanup:
727 	return ret;
728 }
729 
730 static int usbg_submit_command(struct f_uas *, void *, unsigned int);
731 
732 static void uasp_cmd_complete(struct usb_ep *ep, struct usb_request *req)
733 {
734 	struct f_uas *fu = req->context;
735 	int ret;
736 
737 	if (req->status < 0)
738 		return;
739 
740 	ret = usbg_submit_command(fu, req->buf, req->actual);
741 	/*
742 	 * Once we tune for performance enqueue the command req here again so
743 	 * we can receive a second command while we processing this one. Pay
744 	 * attention to properly sync STAUS endpoint with DATA IN + OUT so you
745 	 * don't break HS.
746 	 */
747 	if (!ret)
748 		return;
749 	usb_ep_queue(fu->ep_cmd, fu->cmd.req, GFP_ATOMIC);
750 }
751 
752 static int uasp_alloc_stream_res(struct f_uas *fu, struct uas_stream *stream)
753 {
754 	stream->req_in = usb_ep_alloc_request(fu->ep_in, GFP_KERNEL);
755 	if (!stream->req_in)
756 		goto out;
757 
758 	stream->req_out = usb_ep_alloc_request(fu->ep_out, GFP_KERNEL);
759 	if (!stream->req_out)
760 		goto err_out;
761 
762 	stream->req_status = usb_ep_alloc_request(fu->ep_status, GFP_KERNEL);
763 	if (!stream->req_status)
764 		goto err_sts;
765 
766 	return 0;
767 err_sts:
768 	usb_ep_free_request(fu->ep_status, stream->req_status);
769 	stream->req_status = NULL;
770 err_out:
771 	usb_ep_free_request(fu->ep_out, stream->req_out);
772 	stream->req_out = NULL;
773 out:
774 	return -ENOMEM;
775 }
776 
777 static int uasp_alloc_cmd(struct f_uas *fu)
778 {
779 	fu->cmd.req = usb_ep_alloc_request(fu->ep_cmd, GFP_KERNEL);
780 	if (!fu->cmd.req)
781 		goto err;
782 
783 	fu->cmd.buf = kmalloc(fu->ep_cmd->maxpacket, GFP_KERNEL);
784 	if (!fu->cmd.buf)
785 		goto err_buf;
786 
787 	fu->cmd.req->complete = uasp_cmd_complete;
788 	fu->cmd.req->buf = fu->cmd.buf;
789 	fu->cmd.req->length = fu->ep_cmd->maxpacket;
790 	fu->cmd.req->context = fu;
791 	return 0;
792 
793 err_buf:
794 	usb_ep_free_request(fu->ep_cmd, fu->cmd.req);
795 err:
796 	return -ENOMEM;
797 }
798 
799 static void uasp_setup_stream_res(struct f_uas *fu, int max_streams)
800 {
801 	int i;
802 
803 	for (i = 0; i < max_streams; i++) {
804 		struct uas_stream *s = &fu->stream[i];
805 
806 		s->req_in->stream_id = i + 1;
807 		s->req_out->stream_id = i + 1;
808 		s->req_status->stream_id = i + 1;
809 	}
810 }
811 
812 static int uasp_prepare_reqs(struct f_uas *fu)
813 {
814 	int ret;
815 	int i;
816 	int max_streams;
817 
818 	if (fu->flags & USBG_USE_STREAMS)
819 		max_streams = UASP_SS_EP_COMP_NUM_STREAMS;
820 	else
821 		max_streams = 1;
822 
823 	for (i = 0; i < max_streams; i++) {
824 		ret = uasp_alloc_stream_res(fu, &fu->stream[i]);
825 		if (ret)
826 			goto err_cleanup;
827 	}
828 
829 	ret = uasp_alloc_cmd(fu);
830 	if (ret)
831 		goto err_free_stream;
832 	uasp_setup_stream_res(fu, max_streams);
833 
834 	ret = usb_ep_queue(fu->ep_cmd, fu->cmd.req, GFP_ATOMIC);
835 	if (ret)
836 		goto err_free_stream;
837 
838 	return 0;
839 
840 err_free_stream:
841 	uasp_free_cmdreq(fu);
842 
843 err_cleanup:
844 	if (i) {
845 		do {
846 			uasp_cleanup_one_stream(fu, &fu->stream[i - 1]);
847 			i--;
848 		} while (i);
849 	}
850 	pr_err("UASP: endpoint setup failed\n");
851 	return ret;
852 }
853 
854 static void uasp_set_alt(struct f_uas *fu)
855 {
856 	struct usb_function *f = &fu->function;
857 	struct usb_gadget *gadget = f->config->cdev->gadget;
858 	int ret;
859 
860 	fu->flags = USBG_IS_UAS;
861 
862 	if (gadget->speed == USB_SPEED_SUPER)
863 		fu->flags |= USBG_USE_STREAMS;
864 
865 	config_ep_by_speed(gadget, f, fu->ep_in);
866 	ret = usb_ep_enable(fu->ep_in);
867 	if (ret)
868 		goto err_b_in;
869 
870 	config_ep_by_speed(gadget, f, fu->ep_out);
871 	ret = usb_ep_enable(fu->ep_out);
872 	if (ret)
873 		goto err_b_out;
874 
875 	config_ep_by_speed(gadget, f, fu->ep_cmd);
876 	ret = usb_ep_enable(fu->ep_cmd);
877 	if (ret)
878 		goto err_cmd;
879 	config_ep_by_speed(gadget, f, fu->ep_status);
880 	ret = usb_ep_enable(fu->ep_status);
881 	if (ret)
882 		goto err_status;
883 
884 	ret = uasp_prepare_reqs(fu);
885 	if (ret)
886 		goto err_wq;
887 	fu->flags |= USBG_ENABLED;
888 
889 	pr_info("Using the UAS protocol\n");
890 	return;
891 err_wq:
892 	usb_ep_disable(fu->ep_status);
893 err_status:
894 	usb_ep_disable(fu->ep_cmd);
895 err_cmd:
896 	usb_ep_disable(fu->ep_out);
897 err_b_out:
898 	usb_ep_disable(fu->ep_in);
899 err_b_in:
900 	fu->flags = 0;
901 }
902 
903 static int get_cmd_dir(const unsigned char *cdb)
904 {
905 	int ret;
906 
907 	switch (cdb[0]) {
908 	case READ_6:
909 	case READ_10:
910 	case READ_12:
911 	case READ_16:
912 	case INQUIRY:
913 	case MODE_SENSE:
914 	case MODE_SENSE_10:
915 	case SERVICE_ACTION_IN_16:
916 	case MAINTENANCE_IN:
917 	case PERSISTENT_RESERVE_IN:
918 	case SECURITY_PROTOCOL_IN:
919 	case ACCESS_CONTROL_IN:
920 	case REPORT_LUNS:
921 	case READ_BLOCK_LIMITS:
922 	case READ_POSITION:
923 	case READ_CAPACITY:
924 	case READ_TOC:
925 	case READ_FORMAT_CAPACITIES:
926 	case REQUEST_SENSE:
927 		ret = DMA_FROM_DEVICE;
928 		break;
929 
930 	case WRITE_6:
931 	case WRITE_10:
932 	case WRITE_12:
933 	case WRITE_16:
934 	case MODE_SELECT:
935 	case MODE_SELECT_10:
936 	case WRITE_VERIFY:
937 	case WRITE_VERIFY_12:
938 	case PERSISTENT_RESERVE_OUT:
939 	case MAINTENANCE_OUT:
940 	case SECURITY_PROTOCOL_OUT:
941 	case ACCESS_CONTROL_OUT:
942 		ret = DMA_TO_DEVICE;
943 		break;
944 	case ALLOW_MEDIUM_REMOVAL:
945 	case TEST_UNIT_READY:
946 	case SYNCHRONIZE_CACHE:
947 	case START_STOP:
948 	case ERASE:
949 	case REZERO_UNIT:
950 	case SEEK_10:
951 	case SPACE:
952 	case VERIFY:
953 	case WRITE_FILEMARKS:
954 		ret = DMA_NONE;
955 		break;
956 	default:
957 		pr_warn("target: Unknown data direction for SCSI Opcode "
958 				"0x%02x\n", cdb[0]);
959 		ret = -EINVAL;
960 	}
961 	return ret;
962 }
963 
964 static void usbg_data_write_cmpl(struct usb_ep *ep, struct usb_request *req)
965 {
966 	struct usbg_cmd *cmd = req->context;
967 	struct se_cmd *se_cmd = &cmd->se_cmd;
968 
969 	if (req->status < 0) {
970 		pr_err("%s() state %d transfer failed\n", __func__, cmd->state);
971 		goto cleanup;
972 	}
973 
974 	if (req->num_sgs == 0) {
975 		sg_copy_from_buffer(se_cmd->t_data_sg,
976 				se_cmd->t_data_nents,
977 				cmd->data_buf,
978 				se_cmd->data_length);
979 	}
980 
981 	complete(&cmd->write_complete);
982 	return;
983 
984 cleanup:
985 	usbg_cleanup_cmd(cmd);
986 }
987 
988 static int usbg_prepare_w_request(struct usbg_cmd *cmd, struct usb_request *req)
989 {
990 	struct se_cmd *se_cmd = &cmd->se_cmd;
991 	struct f_uas *fu = cmd->fu;
992 	struct usb_gadget *gadget = fuas_to_gadget(fu);
993 
994 	if (!gadget->sg_supported) {
995 		cmd->data_buf = kmalloc(se_cmd->data_length, GFP_ATOMIC);
996 		if (!cmd->data_buf)
997 			return -ENOMEM;
998 
999 		req->buf = cmd->data_buf;
1000 	} else {
1001 		req->buf = NULL;
1002 		req->num_sgs = se_cmd->t_data_nents;
1003 		req->sg = se_cmd->t_data_sg;
1004 	}
1005 
1006 	req->complete = usbg_data_write_cmpl;
1007 	req->length = se_cmd->data_length;
1008 	req->context = cmd;
1009 	return 0;
1010 }
1011 
1012 static int usbg_send_status_response(struct se_cmd *se_cmd)
1013 {
1014 	struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd,
1015 			se_cmd);
1016 	struct f_uas *fu = cmd->fu;
1017 
1018 	if (fu->flags & USBG_IS_BOT)
1019 		return bot_send_status_response(cmd);
1020 	else
1021 		return uasp_send_status_response(cmd);
1022 }
1023 
1024 static int usbg_send_write_request(struct se_cmd *se_cmd)
1025 {
1026 	struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd,
1027 			se_cmd);
1028 	struct f_uas *fu = cmd->fu;
1029 
1030 	if (fu->flags & USBG_IS_BOT)
1031 		return bot_send_write_request(cmd);
1032 	else
1033 		return uasp_send_write_request(cmd);
1034 }
1035 
1036 static int usbg_send_read_response(struct se_cmd *se_cmd)
1037 {
1038 	struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd,
1039 			se_cmd);
1040 	struct f_uas *fu = cmd->fu;
1041 
1042 	if (fu->flags & USBG_IS_BOT)
1043 		return bot_send_read_response(cmd);
1044 	else
1045 		return uasp_send_read_response(cmd);
1046 }
1047 
1048 static void usbg_cmd_work(struct work_struct *work)
1049 {
1050 	struct usbg_cmd *cmd = container_of(work, struct usbg_cmd, work);
1051 	struct se_cmd *se_cmd;
1052 	struct tcm_usbg_nexus *tv_nexus;
1053 	struct usbg_tpg *tpg;
1054 	int dir;
1055 
1056 	se_cmd = &cmd->se_cmd;
1057 	tpg = cmd->fu->tpg;
1058 	tv_nexus = tpg->tpg_nexus;
1059 	dir = get_cmd_dir(cmd->cmd_buf);
1060 	if (dir < 0) {
1061 		transport_init_se_cmd(se_cmd,
1062 				tv_nexus->tvn_se_sess->se_tpg->se_tpg_tfo,
1063 				tv_nexus->tvn_se_sess, cmd->data_len, DMA_NONE,
1064 				cmd->prio_attr, cmd->sense_iu.sense);
1065 		goto out;
1066 	}
1067 
1068 	if (target_submit_cmd(se_cmd, tv_nexus->tvn_se_sess,
1069 			cmd->cmd_buf, cmd->sense_iu.sense, cmd->unpacked_lun,
1070 			0, cmd->prio_attr, dir, TARGET_SCF_UNKNOWN_SIZE) < 0)
1071 		goto out;
1072 
1073 	return;
1074 
1075 out:
1076 	transport_send_check_condition_and_sense(se_cmd,
1077 			TCM_UNSUPPORTED_SCSI_OPCODE, 1);
1078 	usbg_cleanup_cmd(cmd);
1079 }
1080 
1081 static int usbg_submit_command(struct f_uas *fu,
1082 		void *cmdbuf, unsigned int len)
1083 {
1084 	struct command_iu *cmd_iu = cmdbuf;
1085 	struct usbg_cmd *cmd;
1086 	struct usbg_tpg *tpg;
1087 	struct se_cmd *se_cmd;
1088 	struct tcm_usbg_nexus *tv_nexus;
1089 	u32 cmd_len;
1090 	int ret;
1091 
1092 	if (cmd_iu->iu_id != IU_ID_COMMAND) {
1093 		pr_err("Unsupported type %d\n", cmd_iu->iu_id);
1094 		return -EINVAL;
1095 	}
1096 
1097 	cmd = kzalloc(sizeof *cmd, GFP_ATOMIC);
1098 	if (!cmd)
1099 		return -ENOMEM;
1100 
1101 	cmd->fu = fu;
1102 
1103 	/* XXX until I figure out why I can't free in on complete */
1104 	kref_init(&cmd->ref);
1105 	kref_get(&cmd->ref);
1106 
1107 	tpg = fu->tpg;
1108 	cmd_len = (cmd_iu->len & ~0x3) + 16;
1109 	if (cmd_len > USBG_MAX_CMD)
1110 		goto err;
1111 
1112 	memcpy(cmd->cmd_buf, cmd_iu->cdb, cmd_len);
1113 
1114 	cmd->tag = be16_to_cpup(&cmd_iu->tag);
1115 	if (fu->flags & USBG_USE_STREAMS) {
1116 		if (cmd->tag > UASP_SS_EP_COMP_NUM_STREAMS)
1117 			goto err;
1118 		if (!cmd->tag)
1119 			cmd->stream = &fu->stream[0];
1120 		else
1121 			cmd->stream = &fu->stream[cmd->tag - 1];
1122 	} else {
1123 		cmd->stream = &fu->stream[0];
1124 	}
1125 
1126 	tv_nexus = tpg->tpg_nexus;
1127 	if (!tv_nexus) {
1128 		pr_err("Missing nexus, ignoring command\n");
1129 		goto err;
1130 	}
1131 
1132 	switch (cmd_iu->prio_attr & 0x7) {
1133 	case UAS_HEAD_TAG:
1134 		cmd->prio_attr = TCM_HEAD_TAG;
1135 		break;
1136 	case UAS_ORDERED_TAG:
1137 		cmd->prio_attr = TCM_ORDERED_TAG;
1138 		break;
1139 	case UAS_ACA:
1140 		cmd->prio_attr = TCM_ACA_TAG;
1141 		break;
1142 	default:
1143 		pr_debug_once("Unsupported prio_attr: %02x.\n",
1144 				cmd_iu->prio_attr);
1145 	case UAS_SIMPLE_TAG:
1146 		cmd->prio_attr = TCM_SIMPLE_TAG;
1147 		break;
1148 	}
1149 
1150 	se_cmd = &cmd->se_cmd;
1151 	cmd->unpacked_lun = scsilun_to_int(&cmd_iu->lun);
1152 
1153 	INIT_WORK(&cmd->work, usbg_cmd_work);
1154 	ret = queue_work(tpg->workqueue, &cmd->work);
1155 	if (ret < 0)
1156 		goto err;
1157 
1158 	return 0;
1159 err:
1160 	kfree(cmd);
1161 	return -EINVAL;
1162 }
1163 
1164 static void bot_cmd_work(struct work_struct *work)
1165 {
1166 	struct usbg_cmd *cmd = container_of(work, struct usbg_cmd, work);
1167 	struct se_cmd *se_cmd;
1168 	struct tcm_usbg_nexus *tv_nexus;
1169 	struct usbg_tpg *tpg;
1170 	int dir;
1171 
1172 	se_cmd = &cmd->se_cmd;
1173 	tpg = cmd->fu->tpg;
1174 	tv_nexus = tpg->tpg_nexus;
1175 	dir = get_cmd_dir(cmd->cmd_buf);
1176 	if (dir < 0) {
1177 		transport_init_se_cmd(se_cmd,
1178 				tv_nexus->tvn_se_sess->se_tpg->se_tpg_tfo,
1179 				tv_nexus->tvn_se_sess, cmd->data_len, DMA_NONE,
1180 				cmd->prio_attr, cmd->sense_iu.sense);
1181 		goto out;
1182 	}
1183 
1184 	if (target_submit_cmd(se_cmd, tv_nexus->tvn_se_sess,
1185 			cmd->cmd_buf, cmd->sense_iu.sense, cmd->unpacked_lun,
1186 			cmd->data_len, cmd->prio_attr, dir, 0) < 0)
1187 		goto out;
1188 
1189 	return;
1190 
1191 out:
1192 	transport_send_check_condition_and_sense(se_cmd,
1193 				TCM_UNSUPPORTED_SCSI_OPCODE, 1);
1194 	usbg_cleanup_cmd(cmd);
1195 }
1196 
1197 static int bot_submit_command(struct f_uas *fu,
1198 		void *cmdbuf, unsigned int len)
1199 {
1200 	struct bulk_cb_wrap *cbw = cmdbuf;
1201 	struct usbg_cmd *cmd;
1202 	struct usbg_tpg *tpg;
1203 	struct se_cmd *se_cmd;
1204 	struct tcm_usbg_nexus *tv_nexus;
1205 	u32 cmd_len;
1206 	int ret;
1207 
1208 	if (cbw->Signature != cpu_to_le32(US_BULK_CB_SIGN)) {
1209 		pr_err("Wrong signature on CBW\n");
1210 		return -EINVAL;
1211 	}
1212 	if (len != 31) {
1213 		pr_err("Wrong length for CBW\n");
1214 		return -EINVAL;
1215 	}
1216 
1217 	cmd_len = cbw->Length;
1218 	if (cmd_len < 1 || cmd_len > 16)
1219 		return -EINVAL;
1220 
1221 	cmd = kzalloc(sizeof *cmd, GFP_ATOMIC);
1222 	if (!cmd)
1223 		return -ENOMEM;
1224 
1225 	cmd->fu = fu;
1226 
1227 	/* XXX until I figure out why I can't free in on complete */
1228 	kref_init(&cmd->ref);
1229 	kref_get(&cmd->ref);
1230 
1231 	tpg = fu->tpg;
1232 
1233 	memcpy(cmd->cmd_buf, cbw->CDB, cmd_len);
1234 
1235 	cmd->bot_tag = cbw->Tag;
1236 
1237 	tv_nexus = tpg->tpg_nexus;
1238 	if (!tv_nexus) {
1239 		pr_err("Missing nexus, ignoring command\n");
1240 		goto err;
1241 	}
1242 
1243 	cmd->prio_attr = TCM_SIMPLE_TAG;
1244 	se_cmd = &cmd->se_cmd;
1245 	cmd->unpacked_lun = cbw->Lun;
1246 	cmd->is_read = cbw->Flags & US_BULK_FLAG_IN ? 1 : 0;
1247 	cmd->data_len = le32_to_cpu(cbw->DataTransferLength);
1248 
1249 	INIT_WORK(&cmd->work, bot_cmd_work);
1250 	ret = queue_work(tpg->workqueue, &cmd->work);
1251 	if (ret < 0)
1252 		goto err;
1253 
1254 	return 0;
1255 err:
1256 	kfree(cmd);
1257 	return -EINVAL;
1258 }
1259 
1260 /* Start fabric.c code */
1261 
1262 static int usbg_check_true(struct se_portal_group *se_tpg)
1263 {
1264 	return 1;
1265 }
1266 
1267 static int usbg_check_false(struct se_portal_group *se_tpg)
1268 {
1269 	return 0;
1270 }
1271 
1272 static char *usbg_get_fabric_name(void)
1273 {
1274 	return "usb_gadget";
1275 }
1276 
1277 static u8 usbg_get_fabric_proto_ident(struct se_portal_group *se_tpg)
1278 {
1279 	struct usbg_tpg *tpg = container_of(se_tpg,
1280 				struct usbg_tpg, se_tpg);
1281 	struct usbg_tport *tport = tpg->tport;
1282 	u8 proto_id;
1283 
1284 	switch (tport->tport_proto_id) {
1285 	case SCSI_PROTOCOL_SAS:
1286 	default:
1287 		proto_id = sas_get_fabric_proto_ident(se_tpg);
1288 		break;
1289 	}
1290 
1291 	return proto_id;
1292 }
1293 
1294 static char *usbg_get_fabric_wwn(struct se_portal_group *se_tpg)
1295 {
1296 	struct usbg_tpg *tpg = container_of(se_tpg,
1297 				struct usbg_tpg, se_tpg);
1298 	struct usbg_tport *tport = tpg->tport;
1299 
1300 	return &tport->tport_name[0];
1301 }
1302 
1303 static u16 usbg_get_tag(struct se_portal_group *se_tpg)
1304 {
1305 	struct usbg_tpg *tpg = container_of(se_tpg,
1306 				struct usbg_tpg, se_tpg);
1307 	return tpg->tport_tpgt;
1308 }
1309 
1310 static u32 usbg_get_default_depth(struct se_portal_group *se_tpg)
1311 {
1312 	return 1;
1313 }
1314 
1315 static u32 usbg_get_pr_transport_id(
1316 	struct se_portal_group *se_tpg,
1317 	struct se_node_acl *se_nacl,
1318 	struct t10_pr_registration *pr_reg,
1319 	int *format_code,
1320 	unsigned char *buf)
1321 {
1322 	struct usbg_tpg *tpg = container_of(se_tpg,
1323 				struct usbg_tpg, se_tpg);
1324 	struct usbg_tport *tport = tpg->tport;
1325 	int ret = 0;
1326 
1327 	switch (tport->tport_proto_id) {
1328 	case SCSI_PROTOCOL_SAS:
1329 	default:
1330 		ret = sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1331 					format_code, buf);
1332 		break;
1333 	}
1334 
1335 	return ret;
1336 }
1337 
1338 static u32 usbg_get_pr_transport_id_len(
1339 	struct se_portal_group *se_tpg,
1340 	struct se_node_acl *se_nacl,
1341 	struct t10_pr_registration *pr_reg,
1342 	int *format_code)
1343 {
1344 	struct usbg_tpg *tpg = container_of(se_tpg,
1345 				struct usbg_tpg, se_tpg);
1346 	struct usbg_tport *tport = tpg->tport;
1347 	int ret = 0;
1348 
1349 	switch (tport->tport_proto_id) {
1350 	case SCSI_PROTOCOL_SAS:
1351 	default:
1352 		ret = sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1353 					format_code);
1354 		break;
1355 	}
1356 
1357 	return ret;
1358 }
1359 
1360 static char *usbg_parse_pr_out_transport_id(
1361 	struct se_portal_group *se_tpg,
1362 	const char *buf,
1363 	u32 *out_tid_len,
1364 	char **port_nexus_ptr)
1365 {
1366 	struct usbg_tpg *tpg = container_of(se_tpg,
1367 				struct usbg_tpg, se_tpg);
1368 	struct usbg_tport *tport = tpg->tport;
1369 	char *tid = NULL;
1370 
1371 	switch (tport->tport_proto_id) {
1372 	case SCSI_PROTOCOL_SAS:
1373 	default:
1374 		tid = sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1375 					port_nexus_ptr);
1376 	}
1377 
1378 	return tid;
1379 }
1380 
1381 static struct se_node_acl *usbg_alloc_fabric_acl(struct se_portal_group *se_tpg)
1382 {
1383 	struct usbg_nacl *nacl;
1384 
1385 	nacl = kzalloc(sizeof(struct usbg_nacl), GFP_KERNEL);
1386 	if (!nacl)
1387 		return NULL;
1388 
1389 	return &nacl->se_node_acl;
1390 }
1391 
1392 static void usbg_release_fabric_acl(
1393 	struct se_portal_group *se_tpg,
1394 	struct se_node_acl *se_nacl)
1395 {
1396 	struct usbg_nacl *nacl = container_of(se_nacl,
1397 			struct usbg_nacl, se_node_acl);
1398 	kfree(nacl);
1399 }
1400 
1401 static u32 usbg_tpg_get_inst_index(struct se_portal_group *se_tpg)
1402 {
1403 	return 1;
1404 }
1405 
1406 static void usbg_cmd_release(struct kref *ref)
1407 {
1408 	struct usbg_cmd *cmd = container_of(ref, struct usbg_cmd,
1409 			ref);
1410 
1411 	transport_generic_free_cmd(&cmd->se_cmd, 0);
1412 }
1413 
1414 static void usbg_release_cmd(struct se_cmd *se_cmd)
1415 {
1416 	struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd,
1417 			se_cmd);
1418 	kfree(cmd->data_buf);
1419 	kfree(cmd);
1420 	return;
1421 }
1422 
1423 static int usbg_shutdown_session(struct se_session *se_sess)
1424 {
1425 	return 0;
1426 }
1427 
1428 static void usbg_close_session(struct se_session *se_sess)
1429 {
1430 	return;
1431 }
1432 
1433 static u32 usbg_sess_get_index(struct se_session *se_sess)
1434 {
1435 	return 0;
1436 }
1437 
1438 /*
1439  * XXX Error recovery: return != 0 if we expect writes. Dunno when that could be
1440  */
1441 static int usbg_write_pending_status(struct se_cmd *se_cmd)
1442 {
1443 	return 0;
1444 }
1445 
1446 static void usbg_set_default_node_attrs(struct se_node_acl *nacl)
1447 {
1448 	return;
1449 }
1450 
1451 static u32 usbg_get_task_tag(struct se_cmd *se_cmd)
1452 {
1453 	struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd,
1454 			se_cmd);
1455 	struct f_uas *fu = cmd->fu;
1456 
1457 	if (fu->flags & USBG_IS_BOT)
1458 		return le32_to_cpu(cmd->bot_tag);
1459 	else
1460 		return cmd->tag;
1461 }
1462 
1463 static int usbg_get_cmd_state(struct se_cmd *se_cmd)
1464 {
1465 	return 0;
1466 }
1467 
1468 static void usbg_queue_tm_rsp(struct se_cmd *se_cmd)
1469 {
1470 }
1471 
1472 static void usbg_aborted_task(struct se_cmd *se_cmd)
1473 {
1474 	return;
1475 }
1476 
1477 static const char *usbg_check_wwn(const char *name)
1478 {
1479 	const char *n;
1480 	unsigned int len;
1481 
1482 	n = strstr(name, "naa.");
1483 	if (!n)
1484 		return NULL;
1485 	n += 4;
1486 	len = strlen(n);
1487 	if (len == 0 || len > USBG_NAMELEN - 1)
1488 		return NULL;
1489 	return n;
1490 }
1491 
1492 static struct se_node_acl *usbg_make_nodeacl(
1493 	struct se_portal_group *se_tpg,
1494 	struct config_group *group,
1495 	const char *name)
1496 {
1497 	struct se_node_acl *se_nacl, *se_nacl_new;
1498 	struct usbg_nacl *nacl;
1499 	u64 wwpn = 0;
1500 	u32 nexus_depth;
1501 	const char *wnn_name;
1502 
1503 	wnn_name = usbg_check_wwn(name);
1504 	if (!wnn_name)
1505 		return ERR_PTR(-EINVAL);
1506 	se_nacl_new = usbg_alloc_fabric_acl(se_tpg);
1507 	if (!(se_nacl_new))
1508 		return ERR_PTR(-ENOMEM);
1509 
1510 	nexus_depth = 1;
1511 	/*
1512 	 * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1513 	 * when converting a NodeACL from demo mode -> explict
1514 	 */
1515 	se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1516 				name, nexus_depth);
1517 	if (IS_ERR(se_nacl)) {
1518 		usbg_release_fabric_acl(se_tpg, se_nacl_new);
1519 		return se_nacl;
1520 	}
1521 	/*
1522 	 * Locate our struct usbg_nacl and set the FC Nport WWPN
1523 	 */
1524 	nacl = container_of(se_nacl, struct usbg_nacl, se_node_acl);
1525 	nacl->iport_wwpn = wwpn;
1526 	snprintf(nacl->iport_name, sizeof(nacl->iport_name), "%s", name);
1527 	return se_nacl;
1528 }
1529 
1530 static void usbg_drop_nodeacl(struct se_node_acl *se_acl)
1531 {
1532 	struct usbg_nacl *nacl = container_of(se_acl,
1533 				struct usbg_nacl, se_node_acl);
1534 	core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1535 	kfree(nacl);
1536 }
1537 
1538 struct usbg_tpg *the_only_tpg_I_currently_have;
1539 
1540 static struct se_portal_group *usbg_make_tpg(
1541 	struct se_wwn *wwn,
1542 	struct config_group *group,
1543 	const char *name)
1544 {
1545 	struct usbg_tport *tport = container_of(wwn, struct usbg_tport,
1546 			tport_wwn);
1547 	struct usbg_tpg *tpg;
1548 	unsigned long tpgt;
1549 	int ret;
1550 
1551 	if (strstr(name, "tpgt_") != name)
1552 		return ERR_PTR(-EINVAL);
1553 	if (kstrtoul(name + 5, 0, &tpgt) || tpgt > UINT_MAX)
1554 		return ERR_PTR(-EINVAL);
1555 	if (the_only_tpg_I_currently_have) {
1556 		pr_err("Until the gadget framework can't handle multiple\n");
1557 		pr_err("gadgets, you can't do this here.\n");
1558 		return ERR_PTR(-EBUSY);
1559 	}
1560 
1561 	tpg = kzalloc(sizeof(struct usbg_tpg), GFP_KERNEL);
1562 	if (!tpg)
1563 		return ERR_PTR(-ENOMEM);
1564 	mutex_init(&tpg->tpg_mutex);
1565 	atomic_set(&tpg->tpg_port_count, 0);
1566 	tpg->workqueue = alloc_workqueue("tcm_usb_gadget", 0, 1);
1567 	if (!tpg->workqueue) {
1568 		kfree(tpg);
1569 		return NULL;
1570 	}
1571 
1572 	tpg->tport = tport;
1573 	tpg->tport_tpgt = tpgt;
1574 
1575 	ret = core_tpg_register(&usbg_ops, wwn, &tpg->se_tpg, tpg,
1576 				TRANSPORT_TPG_TYPE_NORMAL);
1577 	if (ret < 0) {
1578 		destroy_workqueue(tpg->workqueue);
1579 		kfree(tpg);
1580 		return NULL;
1581 	}
1582 	the_only_tpg_I_currently_have = tpg;
1583 	return &tpg->se_tpg;
1584 }
1585 
1586 static void usbg_drop_tpg(struct se_portal_group *se_tpg)
1587 {
1588 	struct usbg_tpg *tpg = container_of(se_tpg,
1589 				struct usbg_tpg, se_tpg);
1590 
1591 	core_tpg_deregister(se_tpg);
1592 	destroy_workqueue(tpg->workqueue);
1593 	kfree(tpg);
1594 	the_only_tpg_I_currently_have = NULL;
1595 }
1596 
1597 static struct se_wwn *usbg_make_tport(
1598 	struct target_fabric_configfs *tf,
1599 	struct config_group *group,
1600 	const char *name)
1601 {
1602 	struct usbg_tport *tport;
1603 	const char *wnn_name;
1604 	u64 wwpn = 0;
1605 
1606 	wnn_name = usbg_check_wwn(name);
1607 	if (!wnn_name)
1608 		return ERR_PTR(-EINVAL);
1609 
1610 	tport = kzalloc(sizeof(struct usbg_tport), GFP_KERNEL);
1611 	if (!(tport))
1612 		return ERR_PTR(-ENOMEM);
1613 	tport->tport_wwpn = wwpn;
1614 	snprintf(tport->tport_name, sizeof(tport->tport_name), "%s", wnn_name);
1615 	return &tport->tport_wwn;
1616 }
1617 
1618 static void usbg_drop_tport(struct se_wwn *wwn)
1619 {
1620 	struct usbg_tport *tport = container_of(wwn,
1621 				struct usbg_tport, tport_wwn);
1622 	kfree(tport);
1623 }
1624 
1625 /*
1626  * If somebody feels like dropping the version property, go ahead.
1627  */
1628 static ssize_t usbg_wwn_show_attr_version(
1629 	struct target_fabric_configfs *tf,
1630 	char *page)
1631 {
1632 	return sprintf(page, "usb-gadget fabric module\n");
1633 }
1634 TF_WWN_ATTR_RO(usbg, version);
1635 
1636 static struct configfs_attribute *usbg_wwn_attrs[] = {
1637 	&usbg_wwn_version.attr,
1638 	NULL,
1639 };
1640 
1641 static ssize_t tcm_usbg_tpg_show_enable(
1642 		struct se_portal_group *se_tpg,
1643 		char *page)
1644 {
1645 	struct usbg_tpg  *tpg = container_of(se_tpg, struct usbg_tpg, se_tpg);
1646 
1647 	return snprintf(page, PAGE_SIZE, "%u\n", tpg->gadget_connect);
1648 }
1649 
1650 static int usbg_attach(struct usbg_tpg *);
1651 static void usbg_detach(struct usbg_tpg *);
1652 
1653 static ssize_t tcm_usbg_tpg_store_enable(
1654 		struct se_portal_group *se_tpg,
1655 		const char *page,
1656 		size_t count)
1657 {
1658 	struct usbg_tpg  *tpg = container_of(se_tpg, struct usbg_tpg, se_tpg);
1659 	unsigned long op;
1660 	ssize_t ret;
1661 
1662 	ret = kstrtoul(page, 0, &op);
1663 	if (ret < 0)
1664 		return -EINVAL;
1665 	if (op > 1)
1666 		return -EINVAL;
1667 
1668 	if (op && tpg->gadget_connect)
1669 		goto out;
1670 	if (!op && !tpg->gadget_connect)
1671 		goto out;
1672 
1673 	if (op) {
1674 		ret = usbg_attach(tpg);
1675 		if (ret)
1676 			goto out;
1677 	} else {
1678 		usbg_detach(tpg);
1679 	}
1680 	tpg->gadget_connect = op;
1681 out:
1682 	return count;
1683 }
1684 TF_TPG_BASE_ATTR(tcm_usbg, enable, S_IRUGO | S_IWUSR);
1685 
1686 static ssize_t tcm_usbg_tpg_show_nexus(
1687 		struct se_portal_group *se_tpg,
1688 		char *page)
1689 {
1690 	struct usbg_tpg *tpg = container_of(se_tpg, struct usbg_tpg, se_tpg);
1691 	struct tcm_usbg_nexus *tv_nexus;
1692 	ssize_t ret;
1693 
1694 	mutex_lock(&tpg->tpg_mutex);
1695 	tv_nexus = tpg->tpg_nexus;
1696 	if (!tv_nexus) {
1697 		ret = -ENODEV;
1698 		goto out;
1699 	}
1700 	ret = snprintf(page, PAGE_SIZE, "%s\n",
1701 			tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1702 out:
1703 	mutex_unlock(&tpg->tpg_mutex);
1704 	return ret;
1705 }
1706 
1707 static int tcm_usbg_make_nexus(struct usbg_tpg *tpg, char *name)
1708 {
1709 	struct se_portal_group *se_tpg;
1710 	struct tcm_usbg_nexus *tv_nexus;
1711 	int ret;
1712 
1713 	mutex_lock(&tpg->tpg_mutex);
1714 	if (tpg->tpg_nexus) {
1715 		ret = -EEXIST;
1716 		pr_debug("tpg->tpg_nexus already exists\n");
1717 		goto err_unlock;
1718 	}
1719 	se_tpg = &tpg->se_tpg;
1720 
1721 	ret = -ENOMEM;
1722 	tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
1723 	if (!tv_nexus)
1724 		goto err_unlock;
1725 	tv_nexus->tvn_se_sess = transport_init_session(TARGET_PROT_NORMAL);
1726 	if (IS_ERR(tv_nexus->tvn_se_sess))
1727 		goto err_free;
1728 
1729 	/*
1730 	 * Since we are running in 'demo mode' this call with generate a
1731 	 * struct se_node_acl for the tcm_vhost struct se_portal_group with
1732 	 * the SCSI Initiator port name of the passed configfs group 'name'.
1733 	 */
1734 	tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1735 			se_tpg, name);
1736 	if (!tv_nexus->tvn_se_sess->se_node_acl) {
1737 		pr_debug("core_tpg_check_initiator_node_acl() failed"
1738 				" for %s\n", name);
1739 		goto err_session;
1740 	}
1741 	/*
1742 	 * Now register the TCM vHost virtual I_T Nexus as active.
1743 	 */
1744 	transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1745 			tv_nexus->tvn_se_sess, tv_nexus);
1746 	tpg->tpg_nexus = tv_nexus;
1747 	mutex_unlock(&tpg->tpg_mutex);
1748 	return 0;
1749 
1750 err_session:
1751 	transport_free_session(tv_nexus->tvn_se_sess);
1752 err_free:
1753 	kfree(tv_nexus);
1754 err_unlock:
1755 	mutex_unlock(&tpg->tpg_mutex);
1756 	return ret;
1757 }
1758 
1759 static int tcm_usbg_drop_nexus(struct usbg_tpg *tpg)
1760 {
1761 	struct se_session *se_sess;
1762 	struct tcm_usbg_nexus *tv_nexus;
1763 	int ret = -ENODEV;
1764 
1765 	mutex_lock(&tpg->tpg_mutex);
1766 	tv_nexus = tpg->tpg_nexus;
1767 	if (!tv_nexus)
1768 		goto out;
1769 
1770 	se_sess = tv_nexus->tvn_se_sess;
1771 	if (!se_sess)
1772 		goto out;
1773 
1774 	if (atomic_read(&tpg->tpg_port_count)) {
1775 		ret = -EPERM;
1776 		pr_err("Unable to remove Host I_T Nexus with"
1777 				" active TPG port count: %d\n",
1778 				atomic_read(&tpg->tpg_port_count));
1779 		goto out;
1780 	}
1781 
1782 	pr_debug("Removing I_T Nexus to Initiator Port: %s\n",
1783 			tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1784 	/*
1785 	 * Release the SCSI I_T Nexus to the emulated vHost Target Port
1786 	 */
1787 	transport_deregister_session(tv_nexus->tvn_se_sess);
1788 	tpg->tpg_nexus = NULL;
1789 
1790 	kfree(tv_nexus);
1791 	ret = 0;
1792 out:
1793 	mutex_unlock(&tpg->tpg_mutex);
1794 	return ret;
1795 }
1796 
1797 static ssize_t tcm_usbg_tpg_store_nexus(
1798 		struct se_portal_group *se_tpg,
1799 		const char *page,
1800 		size_t count)
1801 {
1802 	struct usbg_tpg *tpg = container_of(se_tpg, struct usbg_tpg, se_tpg);
1803 	unsigned char i_port[USBG_NAMELEN], *ptr;
1804 	int ret;
1805 
1806 	if (!strncmp(page, "NULL", 4)) {
1807 		ret = tcm_usbg_drop_nexus(tpg);
1808 		return (!ret) ? count : ret;
1809 	}
1810 	if (strlen(page) >= USBG_NAMELEN) {
1811 		pr_err("Emulated NAA Sas Address: %s, exceeds"
1812 				" max: %d\n", page, USBG_NAMELEN);
1813 		return -EINVAL;
1814 	}
1815 	snprintf(i_port, USBG_NAMELEN, "%s", page);
1816 
1817 	ptr = strstr(i_port, "naa.");
1818 	if (!ptr) {
1819 		pr_err("Missing 'naa.' prefix\n");
1820 		return -EINVAL;
1821 	}
1822 
1823 	if (i_port[strlen(i_port) - 1] == '\n')
1824 		i_port[strlen(i_port) - 1] = '\0';
1825 
1826 	ret = tcm_usbg_make_nexus(tpg, &i_port[4]);
1827 	if (ret < 0)
1828 		return ret;
1829 	return count;
1830 }
1831 TF_TPG_BASE_ATTR(tcm_usbg, nexus, S_IRUGO | S_IWUSR);
1832 
1833 static struct configfs_attribute *usbg_base_attrs[] = {
1834 	&tcm_usbg_tpg_enable.attr,
1835 	&tcm_usbg_tpg_nexus.attr,
1836 	NULL,
1837 };
1838 
1839 static int usbg_port_link(struct se_portal_group *se_tpg, struct se_lun *lun)
1840 {
1841 	struct usbg_tpg *tpg = container_of(se_tpg, struct usbg_tpg, se_tpg);
1842 
1843 	atomic_inc(&tpg->tpg_port_count);
1844 	smp_mb__after_atomic();
1845 	return 0;
1846 }
1847 
1848 static void usbg_port_unlink(struct se_portal_group *se_tpg,
1849 		struct se_lun *se_lun)
1850 {
1851 	struct usbg_tpg *tpg = container_of(se_tpg, struct usbg_tpg, se_tpg);
1852 
1853 	atomic_dec(&tpg->tpg_port_count);
1854 	smp_mb__after_atomic();
1855 }
1856 
1857 static int usbg_check_stop_free(struct se_cmd *se_cmd)
1858 {
1859 	struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd,
1860 			se_cmd);
1861 
1862 	kref_put(&cmd->ref, usbg_cmd_release);
1863 	return 1;
1864 }
1865 
1866 static const struct target_core_fabric_ops usbg_ops = {
1867 	.module				= THIS_MODULE,
1868 	.name				= "usb_gadget",
1869 	.get_fabric_name		= usbg_get_fabric_name,
1870 	.get_fabric_proto_ident		= usbg_get_fabric_proto_ident,
1871 	.tpg_get_wwn			= usbg_get_fabric_wwn,
1872 	.tpg_get_tag			= usbg_get_tag,
1873 	.tpg_get_default_depth		= usbg_get_default_depth,
1874 	.tpg_get_pr_transport_id	= usbg_get_pr_transport_id,
1875 	.tpg_get_pr_transport_id_len	= usbg_get_pr_transport_id_len,
1876 	.tpg_parse_pr_out_transport_id	= usbg_parse_pr_out_transport_id,
1877 	.tpg_check_demo_mode		= usbg_check_true,
1878 	.tpg_check_demo_mode_cache	= usbg_check_false,
1879 	.tpg_check_demo_mode_write_protect = usbg_check_false,
1880 	.tpg_check_prod_mode_write_protect = usbg_check_false,
1881 	.tpg_alloc_fabric_acl		= usbg_alloc_fabric_acl,
1882 	.tpg_release_fabric_acl		= usbg_release_fabric_acl,
1883 	.tpg_get_inst_index		= usbg_tpg_get_inst_index,
1884 	.release_cmd			= usbg_release_cmd,
1885 	.shutdown_session		= usbg_shutdown_session,
1886 	.close_session			= usbg_close_session,
1887 	.sess_get_index			= usbg_sess_get_index,
1888 	.sess_get_initiator_sid		= NULL,
1889 	.write_pending			= usbg_send_write_request,
1890 	.write_pending_status		= usbg_write_pending_status,
1891 	.set_default_node_attributes	= usbg_set_default_node_attrs,
1892 	.get_task_tag			= usbg_get_task_tag,
1893 	.get_cmd_state			= usbg_get_cmd_state,
1894 	.queue_data_in			= usbg_send_read_response,
1895 	.queue_status			= usbg_send_status_response,
1896 	.queue_tm_rsp			= usbg_queue_tm_rsp,
1897 	.aborted_task			= usbg_aborted_task,
1898 	.check_stop_free		= usbg_check_stop_free,
1899 
1900 	.fabric_make_wwn		= usbg_make_tport,
1901 	.fabric_drop_wwn		= usbg_drop_tport,
1902 	.fabric_make_tpg		= usbg_make_tpg,
1903 	.fabric_drop_tpg		= usbg_drop_tpg,
1904 	.fabric_post_link		= usbg_port_link,
1905 	.fabric_pre_unlink		= usbg_port_unlink,
1906 	.fabric_make_np			= NULL,
1907 	.fabric_drop_np			= NULL,
1908 	.fabric_make_nodeacl		= usbg_make_nodeacl,
1909 	.fabric_drop_nodeacl		= usbg_drop_nodeacl,
1910 
1911 	.tfc_wwn_attrs			= usbg_wwn_attrs,
1912 	.tfc_tpg_base_attrs		= usbg_base_attrs,
1913 };
1914 
1915 /* Start gadget.c code */
1916 
1917 static struct usb_interface_descriptor bot_intf_desc = {
1918 	.bLength =              sizeof(bot_intf_desc),
1919 	.bDescriptorType =      USB_DT_INTERFACE,
1920 	.bNumEndpoints =        2,
1921 	.bAlternateSetting =	USB_G_ALT_INT_BBB,
1922 	.bInterfaceClass =      USB_CLASS_MASS_STORAGE,
1923 	.bInterfaceSubClass =   USB_SC_SCSI,
1924 	.bInterfaceProtocol =   USB_PR_BULK,
1925 };
1926 
1927 static struct usb_interface_descriptor uasp_intf_desc = {
1928 	.bLength =		sizeof(uasp_intf_desc),
1929 	.bDescriptorType =	USB_DT_INTERFACE,
1930 	.bNumEndpoints =	4,
1931 	.bAlternateSetting =	USB_G_ALT_INT_UAS,
1932 	.bInterfaceClass =	USB_CLASS_MASS_STORAGE,
1933 	.bInterfaceSubClass =	USB_SC_SCSI,
1934 	.bInterfaceProtocol =	USB_PR_UAS,
1935 };
1936 
1937 static struct usb_endpoint_descriptor uasp_bi_desc = {
1938 	.bLength =		USB_DT_ENDPOINT_SIZE,
1939 	.bDescriptorType =	USB_DT_ENDPOINT,
1940 	.bEndpointAddress =	USB_DIR_IN,
1941 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
1942 	.wMaxPacketSize =	cpu_to_le16(512),
1943 };
1944 
1945 static struct usb_endpoint_descriptor uasp_fs_bi_desc = {
1946 	.bLength =		USB_DT_ENDPOINT_SIZE,
1947 	.bDescriptorType =	USB_DT_ENDPOINT,
1948 	.bEndpointAddress =	USB_DIR_IN,
1949 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
1950 };
1951 
1952 static struct usb_pipe_usage_descriptor uasp_bi_pipe_desc = {
1953 	.bLength =		sizeof(uasp_bi_pipe_desc),
1954 	.bDescriptorType =	USB_DT_PIPE_USAGE,
1955 	.bPipeID =		DATA_IN_PIPE_ID,
1956 };
1957 
1958 static struct usb_endpoint_descriptor uasp_ss_bi_desc = {
1959 	.bLength =		USB_DT_ENDPOINT_SIZE,
1960 	.bDescriptorType =	USB_DT_ENDPOINT,
1961 	.bEndpointAddress =	USB_DIR_IN,
1962 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
1963 	.wMaxPacketSize =	cpu_to_le16(1024),
1964 };
1965 
1966 static struct usb_ss_ep_comp_descriptor uasp_bi_ep_comp_desc = {
1967 	.bLength =		sizeof(uasp_bi_ep_comp_desc),
1968 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
1969 	.bMaxBurst =		0,
1970 	.bmAttributes =		UASP_SS_EP_COMP_LOG_STREAMS,
1971 	.wBytesPerInterval =	0,
1972 };
1973 
1974 static struct usb_ss_ep_comp_descriptor bot_bi_ep_comp_desc = {
1975 	.bLength =		sizeof(bot_bi_ep_comp_desc),
1976 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
1977 	.bMaxBurst =		0,
1978 };
1979 
1980 static struct usb_endpoint_descriptor uasp_bo_desc = {
1981 	.bLength =		USB_DT_ENDPOINT_SIZE,
1982 	.bDescriptorType =	USB_DT_ENDPOINT,
1983 	.bEndpointAddress =	USB_DIR_OUT,
1984 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
1985 	.wMaxPacketSize =	cpu_to_le16(512),
1986 };
1987 
1988 static struct usb_endpoint_descriptor uasp_fs_bo_desc = {
1989 	.bLength =		USB_DT_ENDPOINT_SIZE,
1990 	.bDescriptorType =	USB_DT_ENDPOINT,
1991 	.bEndpointAddress =	USB_DIR_OUT,
1992 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
1993 };
1994 
1995 static struct usb_pipe_usage_descriptor uasp_bo_pipe_desc = {
1996 	.bLength =		sizeof(uasp_bo_pipe_desc),
1997 	.bDescriptorType =	USB_DT_PIPE_USAGE,
1998 	.bPipeID =		DATA_OUT_PIPE_ID,
1999 };
2000 
2001 static struct usb_endpoint_descriptor uasp_ss_bo_desc = {
2002 	.bLength =		USB_DT_ENDPOINT_SIZE,
2003 	.bDescriptorType =	USB_DT_ENDPOINT,
2004 	.bEndpointAddress =	USB_DIR_OUT,
2005 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2006 	.wMaxPacketSize =	cpu_to_le16(0x400),
2007 };
2008 
2009 static struct usb_ss_ep_comp_descriptor uasp_bo_ep_comp_desc = {
2010 	.bLength =		sizeof(uasp_bo_ep_comp_desc),
2011 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
2012 	.bmAttributes =		UASP_SS_EP_COMP_LOG_STREAMS,
2013 };
2014 
2015 static struct usb_ss_ep_comp_descriptor bot_bo_ep_comp_desc = {
2016 	.bLength =		sizeof(bot_bo_ep_comp_desc),
2017 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
2018 };
2019 
2020 static struct usb_endpoint_descriptor uasp_status_desc = {
2021 	.bLength =		USB_DT_ENDPOINT_SIZE,
2022 	.bDescriptorType =	USB_DT_ENDPOINT,
2023 	.bEndpointAddress =	USB_DIR_IN,
2024 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2025 	.wMaxPacketSize =	cpu_to_le16(512),
2026 };
2027 
2028 static struct usb_endpoint_descriptor uasp_fs_status_desc = {
2029 	.bLength =		USB_DT_ENDPOINT_SIZE,
2030 	.bDescriptorType =	USB_DT_ENDPOINT,
2031 	.bEndpointAddress =	USB_DIR_IN,
2032 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2033 };
2034 
2035 static struct usb_pipe_usage_descriptor uasp_status_pipe_desc = {
2036 	.bLength =		sizeof(uasp_status_pipe_desc),
2037 	.bDescriptorType =	USB_DT_PIPE_USAGE,
2038 	.bPipeID =		STATUS_PIPE_ID,
2039 };
2040 
2041 static struct usb_endpoint_descriptor uasp_ss_status_desc = {
2042 	.bLength =		USB_DT_ENDPOINT_SIZE,
2043 	.bDescriptorType =	USB_DT_ENDPOINT,
2044 	.bEndpointAddress =	USB_DIR_IN,
2045 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2046 	.wMaxPacketSize =	cpu_to_le16(1024),
2047 };
2048 
2049 static struct usb_ss_ep_comp_descriptor uasp_status_in_ep_comp_desc = {
2050 	.bLength =		sizeof(uasp_status_in_ep_comp_desc),
2051 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
2052 	.bmAttributes =		UASP_SS_EP_COMP_LOG_STREAMS,
2053 };
2054 
2055 static struct usb_endpoint_descriptor uasp_cmd_desc = {
2056 	.bLength =		USB_DT_ENDPOINT_SIZE,
2057 	.bDescriptorType =	USB_DT_ENDPOINT,
2058 	.bEndpointAddress =	USB_DIR_OUT,
2059 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2060 	.wMaxPacketSize =	cpu_to_le16(512),
2061 };
2062 
2063 static struct usb_endpoint_descriptor uasp_fs_cmd_desc = {
2064 	.bLength =		USB_DT_ENDPOINT_SIZE,
2065 	.bDescriptorType =	USB_DT_ENDPOINT,
2066 	.bEndpointAddress =	USB_DIR_OUT,
2067 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2068 };
2069 
2070 static struct usb_pipe_usage_descriptor uasp_cmd_pipe_desc = {
2071 	.bLength =		sizeof(uasp_cmd_pipe_desc),
2072 	.bDescriptorType =	USB_DT_PIPE_USAGE,
2073 	.bPipeID =		CMD_PIPE_ID,
2074 };
2075 
2076 static struct usb_endpoint_descriptor uasp_ss_cmd_desc = {
2077 	.bLength =		USB_DT_ENDPOINT_SIZE,
2078 	.bDescriptorType =	USB_DT_ENDPOINT,
2079 	.bEndpointAddress =	USB_DIR_OUT,
2080 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
2081 	.wMaxPacketSize =	cpu_to_le16(1024),
2082 };
2083 
2084 static struct usb_ss_ep_comp_descriptor uasp_cmd_comp_desc = {
2085 	.bLength =		sizeof(uasp_cmd_comp_desc),
2086 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
2087 };
2088 
2089 static struct usb_descriptor_header *uasp_fs_function_desc[] = {
2090 	(struct usb_descriptor_header *) &bot_intf_desc,
2091 	(struct usb_descriptor_header *) &uasp_fs_bi_desc,
2092 	(struct usb_descriptor_header *) &uasp_fs_bo_desc,
2093 
2094 	(struct usb_descriptor_header *) &uasp_intf_desc,
2095 	(struct usb_descriptor_header *) &uasp_fs_bi_desc,
2096 	(struct usb_descriptor_header *) &uasp_bi_pipe_desc,
2097 	(struct usb_descriptor_header *) &uasp_fs_bo_desc,
2098 	(struct usb_descriptor_header *) &uasp_bo_pipe_desc,
2099 	(struct usb_descriptor_header *) &uasp_fs_status_desc,
2100 	(struct usb_descriptor_header *) &uasp_status_pipe_desc,
2101 	(struct usb_descriptor_header *) &uasp_fs_cmd_desc,
2102 	(struct usb_descriptor_header *) &uasp_cmd_pipe_desc,
2103 	NULL,
2104 };
2105 
2106 static struct usb_descriptor_header *uasp_hs_function_desc[] = {
2107 	(struct usb_descriptor_header *) &bot_intf_desc,
2108 	(struct usb_descriptor_header *) &uasp_bi_desc,
2109 	(struct usb_descriptor_header *) &uasp_bo_desc,
2110 
2111 	(struct usb_descriptor_header *) &uasp_intf_desc,
2112 	(struct usb_descriptor_header *) &uasp_bi_desc,
2113 	(struct usb_descriptor_header *) &uasp_bi_pipe_desc,
2114 	(struct usb_descriptor_header *) &uasp_bo_desc,
2115 	(struct usb_descriptor_header *) &uasp_bo_pipe_desc,
2116 	(struct usb_descriptor_header *) &uasp_status_desc,
2117 	(struct usb_descriptor_header *) &uasp_status_pipe_desc,
2118 	(struct usb_descriptor_header *) &uasp_cmd_desc,
2119 	(struct usb_descriptor_header *) &uasp_cmd_pipe_desc,
2120 	NULL,
2121 };
2122 
2123 static struct usb_descriptor_header *uasp_ss_function_desc[] = {
2124 	(struct usb_descriptor_header *) &bot_intf_desc,
2125 	(struct usb_descriptor_header *) &uasp_ss_bi_desc,
2126 	(struct usb_descriptor_header *) &bot_bi_ep_comp_desc,
2127 	(struct usb_descriptor_header *) &uasp_ss_bo_desc,
2128 	(struct usb_descriptor_header *) &bot_bo_ep_comp_desc,
2129 
2130 	(struct usb_descriptor_header *) &uasp_intf_desc,
2131 	(struct usb_descriptor_header *) &uasp_ss_bi_desc,
2132 	(struct usb_descriptor_header *) &uasp_bi_ep_comp_desc,
2133 	(struct usb_descriptor_header *) &uasp_bi_pipe_desc,
2134 	(struct usb_descriptor_header *) &uasp_ss_bo_desc,
2135 	(struct usb_descriptor_header *) &uasp_bo_ep_comp_desc,
2136 	(struct usb_descriptor_header *) &uasp_bo_pipe_desc,
2137 	(struct usb_descriptor_header *) &uasp_ss_status_desc,
2138 	(struct usb_descriptor_header *) &uasp_status_in_ep_comp_desc,
2139 	(struct usb_descriptor_header *) &uasp_status_pipe_desc,
2140 	(struct usb_descriptor_header *) &uasp_ss_cmd_desc,
2141 	(struct usb_descriptor_header *) &uasp_cmd_comp_desc,
2142 	(struct usb_descriptor_header *) &uasp_cmd_pipe_desc,
2143 	NULL,
2144 };
2145 
2146 #define UAS_VENDOR_ID	0x0525	/* NetChip */
2147 #define UAS_PRODUCT_ID	0xa4a5	/* Linux-USB File-backed Storage Gadget */
2148 
2149 static struct usb_device_descriptor usbg_device_desc = {
2150 	.bLength =		sizeof(usbg_device_desc),
2151 	.bDescriptorType =	USB_DT_DEVICE,
2152 	.bcdUSB =		cpu_to_le16(0x0200),
2153 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
2154 	.idVendor =		cpu_to_le16(UAS_VENDOR_ID),
2155 	.idProduct =		cpu_to_le16(UAS_PRODUCT_ID),
2156 	.bNumConfigurations =   1,
2157 };
2158 
2159 static struct usb_string	usbg_us_strings[] = {
2160 	[USB_GADGET_MANUFACTURER_IDX].s	= "Target Manufactor",
2161 	[USB_GADGET_PRODUCT_IDX].s	= "Target Product",
2162 	[USB_GADGET_SERIAL_IDX].s	= "000000000001",
2163 	[USB_G_STR_CONFIG].s		= "default config",
2164 	[USB_G_STR_INT_UAS].s		= "USB Attached SCSI",
2165 	[USB_G_STR_INT_BBB].s		= "Bulk Only Transport",
2166 	{ },
2167 };
2168 
2169 static struct usb_gadget_strings usbg_stringtab = {
2170 	.language = 0x0409,
2171 	.strings = usbg_us_strings,
2172 };
2173 
2174 static struct usb_gadget_strings *usbg_strings[] = {
2175 	&usbg_stringtab,
2176 	NULL,
2177 };
2178 
2179 static int guas_unbind(struct usb_composite_dev *cdev)
2180 {
2181 	return 0;
2182 }
2183 
2184 static struct usb_configuration usbg_config_driver = {
2185 	.label                  = "Linux Target",
2186 	.bConfigurationValue    = 1,
2187 	.bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
2188 };
2189 
2190 static void give_back_ep(struct usb_ep **pep)
2191 {
2192 	struct usb_ep *ep = *pep;
2193 	if (!ep)
2194 		return;
2195 	ep->driver_data = NULL;
2196 }
2197 
2198 static int usbg_bind(struct usb_configuration *c, struct usb_function *f)
2199 {
2200 	struct f_uas		*fu = to_f_uas(f);
2201 	struct usb_gadget	*gadget = c->cdev->gadget;
2202 	struct usb_ep		*ep;
2203 	int			iface;
2204 	int			ret;
2205 
2206 	iface = usb_interface_id(c, f);
2207 	if (iface < 0)
2208 		return iface;
2209 
2210 	bot_intf_desc.bInterfaceNumber = iface;
2211 	uasp_intf_desc.bInterfaceNumber = iface;
2212 	fu->iface = iface;
2213 	ep = usb_ep_autoconfig_ss(gadget, &uasp_ss_bi_desc,
2214 			&uasp_bi_ep_comp_desc);
2215 	if (!ep)
2216 		goto ep_fail;
2217 
2218 	ep->driver_data = fu;
2219 	fu->ep_in = ep;
2220 
2221 	ep = usb_ep_autoconfig_ss(gadget, &uasp_ss_bo_desc,
2222 			&uasp_bo_ep_comp_desc);
2223 	if (!ep)
2224 		goto ep_fail;
2225 	ep->driver_data = fu;
2226 	fu->ep_out = ep;
2227 
2228 	ep = usb_ep_autoconfig_ss(gadget, &uasp_ss_status_desc,
2229 			&uasp_status_in_ep_comp_desc);
2230 	if (!ep)
2231 		goto ep_fail;
2232 	ep->driver_data = fu;
2233 	fu->ep_status = ep;
2234 
2235 	ep = usb_ep_autoconfig_ss(gadget, &uasp_ss_cmd_desc,
2236 			&uasp_cmd_comp_desc);
2237 	if (!ep)
2238 		goto ep_fail;
2239 	ep->driver_data = fu;
2240 	fu->ep_cmd = ep;
2241 
2242 	/* Assume endpoint addresses are the same for both speeds */
2243 	uasp_bi_desc.bEndpointAddress =	uasp_ss_bi_desc.bEndpointAddress;
2244 	uasp_bo_desc.bEndpointAddress = uasp_ss_bo_desc.bEndpointAddress;
2245 	uasp_status_desc.bEndpointAddress =
2246 		uasp_ss_status_desc.bEndpointAddress;
2247 	uasp_cmd_desc.bEndpointAddress = uasp_ss_cmd_desc.bEndpointAddress;
2248 
2249 	uasp_fs_bi_desc.bEndpointAddress = uasp_ss_bi_desc.bEndpointAddress;
2250 	uasp_fs_bo_desc.bEndpointAddress = uasp_ss_bo_desc.bEndpointAddress;
2251 	uasp_fs_status_desc.bEndpointAddress =
2252 		uasp_ss_status_desc.bEndpointAddress;
2253 	uasp_fs_cmd_desc.bEndpointAddress = uasp_ss_cmd_desc.bEndpointAddress;
2254 
2255 	ret = usb_assign_descriptors(f, uasp_fs_function_desc,
2256 			uasp_hs_function_desc, uasp_ss_function_desc);
2257 	if (ret)
2258 		goto ep_fail;
2259 
2260 	return 0;
2261 ep_fail:
2262 	pr_err("Can't claim all required eps\n");
2263 
2264 	give_back_ep(&fu->ep_in);
2265 	give_back_ep(&fu->ep_out);
2266 	give_back_ep(&fu->ep_status);
2267 	give_back_ep(&fu->ep_cmd);
2268 	return -ENOTSUPP;
2269 }
2270 
2271 static void usbg_unbind(struct usb_configuration *c, struct usb_function *f)
2272 {
2273 	struct f_uas *fu = to_f_uas(f);
2274 
2275 	usb_free_all_descriptors(f);
2276 	kfree(fu);
2277 }
2278 
2279 struct guas_setup_wq {
2280 	struct work_struct work;
2281 	struct f_uas *fu;
2282 	unsigned int alt;
2283 };
2284 
2285 static void usbg_delayed_set_alt(struct work_struct *wq)
2286 {
2287 	struct guas_setup_wq *work = container_of(wq, struct guas_setup_wq,
2288 			work);
2289 	struct f_uas *fu = work->fu;
2290 	int alt = work->alt;
2291 
2292 	kfree(work);
2293 
2294 	if (fu->flags & USBG_IS_BOT)
2295 		bot_cleanup_old_alt(fu);
2296 	if (fu->flags & USBG_IS_UAS)
2297 		uasp_cleanup_old_alt(fu);
2298 
2299 	if (alt == USB_G_ALT_INT_BBB)
2300 		bot_set_alt(fu);
2301 	else if (alt == USB_G_ALT_INT_UAS)
2302 		uasp_set_alt(fu);
2303 	usb_composite_setup_continue(fu->function.config->cdev);
2304 }
2305 
2306 static int usbg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2307 {
2308 	struct f_uas *fu = to_f_uas(f);
2309 
2310 	if ((alt == USB_G_ALT_INT_BBB) || (alt == USB_G_ALT_INT_UAS)) {
2311 		struct guas_setup_wq *work;
2312 
2313 		work = kmalloc(sizeof(*work), GFP_ATOMIC);
2314 		if (!work)
2315 			return -ENOMEM;
2316 		INIT_WORK(&work->work, usbg_delayed_set_alt);
2317 		work->fu = fu;
2318 		work->alt = alt;
2319 		schedule_work(&work->work);
2320 		return USB_GADGET_DELAYED_STATUS;
2321 	}
2322 	return -EOPNOTSUPP;
2323 }
2324 
2325 static void usbg_disable(struct usb_function *f)
2326 {
2327 	struct f_uas *fu = to_f_uas(f);
2328 
2329 	if (fu->flags & USBG_IS_UAS)
2330 		uasp_cleanup_old_alt(fu);
2331 	else if (fu->flags & USBG_IS_BOT)
2332 		bot_cleanup_old_alt(fu);
2333 	fu->flags = 0;
2334 }
2335 
2336 static int usbg_setup(struct usb_function *f,
2337 		const struct usb_ctrlrequest *ctrl)
2338 {
2339 	struct f_uas *fu = to_f_uas(f);
2340 
2341 	if (!(fu->flags & USBG_IS_BOT))
2342 		return -EOPNOTSUPP;
2343 
2344 	return usbg_bot_setup(f, ctrl);
2345 }
2346 
2347 static int usbg_cfg_bind(struct usb_configuration *c)
2348 {
2349 	struct f_uas *fu;
2350 	int ret;
2351 
2352 	fu = kzalloc(sizeof(*fu), GFP_KERNEL);
2353 	if (!fu)
2354 		return -ENOMEM;
2355 	fu->function.name = "Target Function";
2356 	fu->function.bind = usbg_bind;
2357 	fu->function.unbind = usbg_unbind;
2358 	fu->function.set_alt = usbg_set_alt;
2359 	fu->function.setup = usbg_setup;
2360 	fu->function.disable = usbg_disable;
2361 	fu->tpg = the_only_tpg_I_currently_have;
2362 
2363 	bot_intf_desc.iInterface = usbg_us_strings[USB_G_STR_INT_BBB].id;
2364 	uasp_intf_desc.iInterface = usbg_us_strings[USB_G_STR_INT_UAS].id;
2365 
2366 	ret = usb_add_function(c, &fu->function);
2367 	if (ret)
2368 		goto err;
2369 
2370 	return 0;
2371 err:
2372 	kfree(fu);
2373 	return ret;
2374 }
2375 
2376 static int usb_target_bind(struct usb_composite_dev *cdev)
2377 {
2378 	int ret;
2379 
2380 	ret = usb_string_ids_tab(cdev, usbg_us_strings);
2381 	if (ret)
2382 		return ret;
2383 
2384 	usbg_device_desc.iManufacturer =
2385 		usbg_us_strings[USB_GADGET_MANUFACTURER_IDX].id;
2386 	usbg_device_desc.iProduct = usbg_us_strings[USB_GADGET_PRODUCT_IDX].id;
2387 	usbg_device_desc.iSerialNumber =
2388 		usbg_us_strings[USB_GADGET_SERIAL_IDX].id;
2389 	usbg_config_driver.iConfiguration =
2390 		usbg_us_strings[USB_G_STR_CONFIG].id;
2391 
2392 	ret = usb_add_config(cdev, &usbg_config_driver,
2393 			usbg_cfg_bind);
2394 	if (ret)
2395 		return ret;
2396 	usb_composite_overwrite_options(cdev, &coverwrite);
2397 	return 0;
2398 }
2399 
2400 static __refdata struct usb_composite_driver usbg_driver = {
2401 	.name           = "g_target",
2402 	.dev            = &usbg_device_desc,
2403 	.strings        = usbg_strings,
2404 	.max_speed      = USB_SPEED_SUPER,
2405 	.bind		= usb_target_bind,
2406 	.unbind         = guas_unbind,
2407 };
2408 
2409 static int usbg_attach(struct usbg_tpg *tpg)
2410 {
2411 	return usb_composite_probe(&usbg_driver);
2412 }
2413 
2414 static void usbg_detach(struct usbg_tpg *tpg)
2415 {
2416 	usb_composite_unregister(&usbg_driver);
2417 }
2418 
2419 static int __init usb_target_gadget_init(void)
2420 {
2421 	return target_register_template(&usbg_ops);
2422 }
2423 module_init(usb_target_gadget_init);
2424 
2425 static void __exit usb_target_gadget_exit(void)
2426 {
2427 	target_unregister_template(&usbg_ops);
2428 }
2429 module_exit(usb_target_gadget_exit);
2430 
2431 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
2432 MODULE_DESCRIPTION("usb-gadget fabric");
2433 MODULE_LICENSE("GPL v2");
2434