xref: /linux/drivers/usb/storage/uas.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * USB Attached SCSI
4  * Note that this is not the same as the USB Mass Storage driver
5  *
6  * Copyright Hans de Goede <hdegoede@redhat.com> for Red Hat, Inc. 2013 - 2016
7  * Copyright Matthew Wilcox for Intel Corp, 2010
8  * Copyright Sarah Sharp for Intel Corp, 2010
9  */
10 
11 #include <linux/blkdev.h>
12 #include <linux/slab.h>
13 #include <linux/types.h>
14 #include <linux/module.h>
15 #include <linux/usb.h>
16 #include <linux/usb_usual.h>
17 #include <linux/usb/hcd.h>
18 #include <linux/usb/storage.h>
19 #include <linux/usb/uas.h>
20 
21 #include <scsi/scsi.h>
22 #include <scsi/scsi_eh.h>
23 #include <scsi/scsi_dbg.h>
24 #include <scsi/scsi_cmnd.h>
25 #include <scsi/scsi_device.h>
26 #include <scsi/scsi_host.h>
27 #include <scsi/scsi_tcq.h>
28 
29 #include "uas-detect.h"
30 #include "scsiglue.h"
31 
32 #define MAX_CMNDS 256
33 
34 struct uas_dev_info {
35 	struct usb_interface *intf;
36 	struct usb_device *udev;
37 	struct usb_anchor cmd_urbs;
38 	struct usb_anchor sense_urbs;
39 	struct usb_anchor data_urbs;
40 	unsigned long flags;
41 	int qdepth, resetting;
42 	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
43 	unsigned use_streams:1;
44 	unsigned shutdown:1;
45 	struct scsi_cmnd *cmnd[MAX_CMNDS];
46 	spinlock_t lock;
47 	struct work_struct work;
48 };
49 
50 enum {
51 	SUBMIT_STATUS_URB	= BIT(1),
52 	ALLOC_DATA_IN_URB	= BIT(2),
53 	SUBMIT_DATA_IN_URB	= BIT(3),
54 	ALLOC_DATA_OUT_URB	= BIT(4),
55 	SUBMIT_DATA_OUT_URB	= BIT(5),
56 	ALLOC_CMD_URB		= BIT(6),
57 	SUBMIT_CMD_URB		= BIT(7),
58 	COMMAND_INFLIGHT        = BIT(8),
59 	DATA_IN_URB_INFLIGHT    = BIT(9),
60 	DATA_OUT_URB_INFLIGHT   = BIT(10),
61 	COMMAND_ABORTED         = BIT(11),
62 	IS_IN_WORK_LIST         = BIT(12),
63 };
64 
65 /* Overrides scsi_pointer */
66 struct uas_cmd_info {
67 	unsigned int state;
68 	unsigned int uas_tag;
69 	struct urb *cmd_urb;
70 	struct urb *data_in_urb;
71 	struct urb *data_out_urb;
72 };
73 
74 /* I hate forward declarations, but I actually have a loop */
75 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
76 				struct uas_dev_info *devinfo);
77 static void uas_do_work(struct work_struct *work);
78 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller);
79 static void uas_free_streams(struct uas_dev_info *devinfo);
80 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
81 				int status);
82 
83 static void uas_do_work(struct work_struct *work)
84 {
85 	struct uas_dev_info *devinfo =
86 		container_of(work, struct uas_dev_info, work);
87 	struct uas_cmd_info *cmdinfo;
88 	struct scsi_cmnd *cmnd;
89 	unsigned long flags;
90 	int i, err;
91 
92 	spin_lock_irqsave(&devinfo->lock, flags);
93 
94 	if (devinfo->resetting)
95 		goto out;
96 
97 	for (i = 0; i < devinfo->qdepth; i++) {
98 		if (!devinfo->cmnd[i])
99 			continue;
100 
101 		cmnd = devinfo->cmnd[i];
102 		cmdinfo = (void *)&cmnd->SCp;
103 
104 		if (!(cmdinfo->state & IS_IN_WORK_LIST))
105 			continue;
106 
107 		err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
108 		if (!err)
109 			cmdinfo->state &= ~IS_IN_WORK_LIST;
110 		else
111 			schedule_work(&devinfo->work);
112 	}
113 out:
114 	spin_unlock_irqrestore(&devinfo->lock, flags);
115 }
116 
117 static void uas_add_work(struct uas_cmd_info *cmdinfo)
118 {
119 	struct scsi_pointer *scp = (void *)cmdinfo;
120 	struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
121 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
122 
123 	lockdep_assert_held(&devinfo->lock);
124 	cmdinfo->state |= IS_IN_WORK_LIST;
125 	schedule_work(&devinfo->work);
126 }
127 
128 static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
129 {
130 	struct uas_cmd_info *cmdinfo;
131 	struct scsi_cmnd *cmnd;
132 	unsigned long flags;
133 	int i, err;
134 
135 	spin_lock_irqsave(&devinfo->lock, flags);
136 	for (i = 0; i < devinfo->qdepth; i++) {
137 		if (!devinfo->cmnd[i])
138 			continue;
139 
140 		cmnd = devinfo->cmnd[i];
141 		cmdinfo = (void *)&cmnd->SCp;
142 		uas_log_cmd_state(cmnd, __func__, 0);
143 		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
144 		cmdinfo->state &= ~COMMAND_INFLIGHT;
145 		cmnd->result = result << 16;
146 		err = uas_try_complete(cmnd, __func__);
147 		WARN_ON(err != 0);
148 	}
149 	spin_unlock_irqrestore(&devinfo->lock, flags);
150 }
151 
152 static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
153 {
154 	struct sense_iu *sense_iu = urb->transfer_buffer;
155 	struct scsi_device *sdev = cmnd->device;
156 
157 	if (urb->actual_length > 16) {
158 		unsigned len = be16_to_cpup(&sense_iu->len);
159 		if (len + 16 != urb->actual_length) {
160 			int newlen = min(len + 16, urb->actual_length) - 16;
161 			if (newlen < 0)
162 				newlen = 0;
163 			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
164 				"disagrees with IU sense data length %d, "
165 				"using %d bytes of sense data\n", __func__,
166 					urb->actual_length, len, newlen);
167 			len = newlen;
168 		}
169 		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
170 	}
171 
172 	cmnd->result = sense_iu->status;
173 }
174 
175 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
176 			      int status)
177 {
178 	struct uas_cmd_info *ci = (void *)&cmnd->SCp;
179 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
180 
181 	scmd_printk(KERN_INFO, cmnd,
182 		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
183 		    prefix, status, cmdinfo->uas_tag,
184 		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
185 		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
186 		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
187 		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
188 		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
189 		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
190 		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
191 		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
192 		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
193 		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
194 		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
195 		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
196 	scsi_print_command(cmnd);
197 }
198 
199 static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
200 {
201 	struct uas_cmd_info *cmdinfo;
202 
203 	if (!cmnd)
204 		return;
205 
206 	cmdinfo = (void *)&cmnd->SCp;
207 
208 	if (cmdinfo->state & SUBMIT_CMD_URB)
209 		usb_free_urb(cmdinfo->cmd_urb);
210 
211 	/* data urbs may have never gotten their submit flag set */
212 	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
213 		usb_free_urb(cmdinfo->data_in_urb);
214 	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
215 		usb_free_urb(cmdinfo->data_out_urb);
216 }
217 
218 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
219 {
220 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
221 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
222 
223 	lockdep_assert_held(&devinfo->lock);
224 	if (cmdinfo->state & (COMMAND_INFLIGHT |
225 			      DATA_IN_URB_INFLIGHT |
226 			      DATA_OUT_URB_INFLIGHT |
227 			      COMMAND_ABORTED))
228 		return -EBUSY;
229 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
230 	uas_free_unsubmitted_urbs(cmnd);
231 	cmnd->scsi_done(cmnd);
232 	return 0;
233 }
234 
235 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
236 			  unsigned direction)
237 {
238 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
239 	int err;
240 
241 	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
242 	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
243 	if (err) {
244 		uas_add_work(cmdinfo);
245 	}
246 }
247 
248 static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
249 {
250 	u8 response_code = riu->response_code;
251 
252 	switch (response_code) {
253 	case RC_INCORRECT_LUN:
254 		cmnd->result = DID_BAD_TARGET << 16;
255 		break;
256 	case RC_TMF_SUCCEEDED:
257 		cmnd->result = DID_OK << 16;
258 		break;
259 	case RC_TMF_NOT_SUPPORTED:
260 		cmnd->result = DID_TARGET_FAILURE << 16;
261 		break;
262 	default:
263 		uas_log_cmd_state(cmnd, "response iu", response_code);
264 		cmnd->result = DID_ERROR << 16;
265 		break;
266 	}
267 
268 	return response_code == RC_TMF_SUCCEEDED;
269 }
270 
271 static void uas_stat_cmplt(struct urb *urb)
272 {
273 	struct iu *iu = urb->transfer_buffer;
274 	struct Scsi_Host *shost = urb->context;
275 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
276 	struct urb *data_in_urb = NULL;
277 	struct urb *data_out_urb = NULL;
278 	struct scsi_cmnd *cmnd;
279 	struct uas_cmd_info *cmdinfo;
280 	unsigned long flags;
281 	unsigned int idx;
282 	int status = urb->status;
283 	bool success;
284 
285 	spin_lock_irqsave(&devinfo->lock, flags);
286 
287 	if (devinfo->resetting)
288 		goto out;
289 
290 	if (status) {
291 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
292 			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
293 		goto out;
294 	}
295 
296 	idx = be16_to_cpup(&iu->tag) - 1;
297 	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
298 		dev_err(&urb->dev->dev,
299 			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
300 		goto out;
301 	}
302 
303 	cmnd = devinfo->cmnd[idx];
304 	cmdinfo = (void *)&cmnd->SCp;
305 
306 	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
307 		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
308 		goto out;
309 	}
310 
311 	switch (iu->iu_id) {
312 	case IU_ID_STATUS:
313 		uas_sense(urb, cmnd);
314 		if (cmnd->result != 0) {
315 			/* cancel data transfers on error */
316 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
317 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
318 		}
319 		cmdinfo->state &= ~COMMAND_INFLIGHT;
320 		uas_try_complete(cmnd, __func__);
321 		break;
322 	case IU_ID_READ_READY:
323 		if (!cmdinfo->data_in_urb ||
324 				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
325 			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
326 			break;
327 		}
328 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
329 		break;
330 	case IU_ID_WRITE_READY:
331 		if (!cmdinfo->data_out_urb ||
332 				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
333 			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
334 			break;
335 		}
336 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
337 		break;
338 	case IU_ID_RESPONSE:
339 		cmdinfo->state &= ~COMMAND_INFLIGHT;
340 		success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
341 		if (!success) {
342 			/* Error, cancel data transfers */
343 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
344 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
345 		}
346 		uas_try_complete(cmnd, __func__);
347 		break;
348 	default:
349 		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
350 	}
351 out:
352 	usb_free_urb(urb);
353 	spin_unlock_irqrestore(&devinfo->lock, flags);
354 
355 	/* Unlinking of data urbs must be done without holding the lock */
356 	if (data_in_urb) {
357 		usb_unlink_urb(data_in_urb);
358 		usb_put_urb(data_in_urb);
359 	}
360 	if (data_out_urb) {
361 		usb_unlink_urb(data_out_urb);
362 		usb_put_urb(data_out_urb);
363 	}
364 }
365 
366 static void uas_data_cmplt(struct urb *urb)
367 {
368 	struct scsi_cmnd *cmnd = urb->context;
369 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
370 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
371 	struct scsi_data_buffer *sdb = NULL;
372 	unsigned long flags;
373 	int status = urb->status;
374 
375 	spin_lock_irqsave(&devinfo->lock, flags);
376 
377 	if (cmdinfo->data_in_urb == urb) {
378 		sdb = scsi_in(cmnd);
379 		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
380 		cmdinfo->data_in_urb = NULL;
381 	} else if (cmdinfo->data_out_urb == urb) {
382 		sdb = scsi_out(cmnd);
383 		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
384 		cmdinfo->data_out_urb = NULL;
385 	}
386 	if (sdb == NULL) {
387 		WARN_ON_ONCE(1);
388 		goto out;
389 	}
390 
391 	if (devinfo->resetting)
392 		goto out;
393 
394 	/* Data urbs should not complete before the cmd urb is submitted */
395 	if (cmdinfo->state & SUBMIT_CMD_URB) {
396 		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
397 		goto out;
398 	}
399 
400 	if (status) {
401 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
402 			uas_log_cmd_state(cmnd, "data cmplt err", status);
403 		/* error: no data transfered */
404 		sdb->resid = sdb->length;
405 	} else {
406 		sdb->resid = sdb->length - urb->actual_length;
407 	}
408 	uas_try_complete(cmnd, __func__);
409 out:
410 	usb_free_urb(urb);
411 	spin_unlock_irqrestore(&devinfo->lock, flags);
412 }
413 
414 static void uas_cmd_cmplt(struct urb *urb)
415 {
416 	if (urb->status)
417 		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
418 
419 	usb_free_urb(urb);
420 }
421 
422 static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
423 				      struct scsi_cmnd *cmnd,
424 				      enum dma_data_direction dir)
425 {
426 	struct usb_device *udev = devinfo->udev;
427 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
428 	struct urb *urb = usb_alloc_urb(0, gfp);
429 	struct scsi_data_buffer *sdb = (dir == DMA_FROM_DEVICE)
430 		? scsi_in(cmnd) : scsi_out(cmnd);
431 	unsigned int pipe = (dir == DMA_FROM_DEVICE)
432 		? devinfo->data_in_pipe : devinfo->data_out_pipe;
433 
434 	if (!urb)
435 		goto out;
436 	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
437 			  uas_data_cmplt, cmnd);
438 	if (devinfo->use_streams)
439 		urb->stream_id = cmdinfo->uas_tag;
440 	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
441 	urb->sg = sdb->table.sgl;
442  out:
443 	return urb;
444 }
445 
446 static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
447 				       struct scsi_cmnd *cmnd)
448 {
449 	struct usb_device *udev = devinfo->udev;
450 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
451 	struct urb *urb = usb_alloc_urb(0, gfp);
452 	struct sense_iu *iu;
453 
454 	if (!urb)
455 		goto out;
456 
457 	iu = kzalloc(sizeof(*iu), gfp);
458 	if (!iu)
459 		goto free;
460 
461 	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
462 			  uas_stat_cmplt, cmnd->device->host);
463 	if (devinfo->use_streams)
464 		urb->stream_id = cmdinfo->uas_tag;
465 	urb->transfer_flags |= URB_FREE_BUFFER;
466  out:
467 	return urb;
468  free:
469 	usb_free_urb(urb);
470 	return NULL;
471 }
472 
473 static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
474 					struct scsi_cmnd *cmnd)
475 {
476 	struct usb_device *udev = devinfo->udev;
477 	struct scsi_device *sdev = cmnd->device;
478 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
479 	struct urb *urb = usb_alloc_urb(0, gfp);
480 	struct command_iu *iu;
481 	int len;
482 
483 	if (!urb)
484 		goto out;
485 
486 	len = cmnd->cmd_len - 16;
487 	if (len < 0)
488 		len = 0;
489 	len = ALIGN(len, 4);
490 	iu = kzalloc(sizeof(*iu) + len, gfp);
491 	if (!iu)
492 		goto free;
493 
494 	iu->iu_id = IU_ID_COMMAND;
495 	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
496 	iu->prio_attr = UAS_SIMPLE_TAG;
497 	iu->len = len;
498 	int_to_scsilun(sdev->lun, &iu->lun);
499 	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
500 
501 	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
502 							uas_cmd_cmplt, NULL);
503 	urb->transfer_flags |= URB_FREE_BUFFER;
504  out:
505 	return urb;
506  free:
507 	usb_free_urb(urb);
508 	return NULL;
509 }
510 
511 /*
512  * Why should I request the Status IU before sending the Command IU?  Spec
513  * says to, but also says the device may receive them in any order.  Seems
514  * daft to me.
515  */
516 
517 static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
518 {
519 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
520 	struct urb *urb;
521 	int err;
522 
523 	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
524 	if (!urb)
525 		return NULL;
526 	usb_anchor_urb(urb, &devinfo->sense_urbs);
527 	err = usb_submit_urb(urb, gfp);
528 	if (err) {
529 		usb_unanchor_urb(urb);
530 		uas_log_cmd_state(cmnd, "sense submit err", err);
531 		usb_free_urb(urb);
532 		return NULL;
533 	}
534 	return urb;
535 }
536 
537 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
538 			   struct uas_dev_info *devinfo)
539 {
540 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
541 	struct urb *urb;
542 	int err;
543 
544 	lockdep_assert_held(&devinfo->lock);
545 	if (cmdinfo->state & SUBMIT_STATUS_URB) {
546 		urb = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
547 		if (!urb)
548 			return SCSI_MLQUEUE_DEVICE_BUSY;
549 		cmdinfo->state &= ~SUBMIT_STATUS_URB;
550 	}
551 
552 	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
553 		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
554 							cmnd, DMA_FROM_DEVICE);
555 		if (!cmdinfo->data_in_urb)
556 			return SCSI_MLQUEUE_DEVICE_BUSY;
557 		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
558 	}
559 
560 	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
561 		usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
562 		err = usb_submit_urb(cmdinfo->data_in_urb, GFP_ATOMIC);
563 		if (err) {
564 			usb_unanchor_urb(cmdinfo->data_in_urb);
565 			uas_log_cmd_state(cmnd, "data in submit err", err);
566 			return SCSI_MLQUEUE_DEVICE_BUSY;
567 		}
568 		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
569 		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
570 	}
571 
572 	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
573 		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
574 							cmnd, DMA_TO_DEVICE);
575 		if (!cmdinfo->data_out_urb)
576 			return SCSI_MLQUEUE_DEVICE_BUSY;
577 		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
578 	}
579 
580 	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
581 		usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
582 		err = usb_submit_urb(cmdinfo->data_out_urb, GFP_ATOMIC);
583 		if (err) {
584 			usb_unanchor_urb(cmdinfo->data_out_urb);
585 			uas_log_cmd_state(cmnd, "data out submit err", err);
586 			return SCSI_MLQUEUE_DEVICE_BUSY;
587 		}
588 		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
589 		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
590 	}
591 
592 	if (cmdinfo->state & ALLOC_CMD_URB) {
593 		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
594 		if (!cmdinfo->cmd_urb)
595 			return SCSI_MLQUEUE_DEVICE_BUSY;
596 		cmdinfo->state &= ~ALLOC_CMD_URB;
597 	}
598 
599 	if (cmdinfo->state & SUBMIT_CMD_URB) {
600 		usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
601 		err = usb_submit_urb(cmdinfo->cmd_urb, GFP_ATOMIC);
602 		if (err) {
603 			usb_unanchor_urb(cmdinfo->cmd_urb);
604 			uas_log_cmd_state(cmnd, "cmd submit err", err);
605 			return SCSI_MLQUEUE_DEVICE_BUSY;
606 		}
607 		cmdinfo->cmd_urb = NULL;
608 		cmdinfo->state &= ~SUBMIT_CMD_URB;
609 		cmdinfo->state |= COMMAND_INFLIGHT;
610 	}
611 
612 	return 0;
613 }
614 
615 static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
616 					void (*done)(struct scsi_cmnd *))
617 {
618 	struct scsi_device *sdev = cmnd->device;
619 	struct uas_dev_info *devinfo = sdev->hostdata;
620 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
621 	unsigned long flags;
622 	int idx, err;
623 
624 	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
625 
626 	/* Re-check scsi_block_requests now that we've the host-lock */
627 	if (cmnd->device->host->host_self_blocked)
628 		return SCSI_MLQUEUE_DEVICE_BUSY;
629 
630 	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
631 			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
632 		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
633 		       sizeof(usb_stor_sense_invalidCDB));
634 		cmnd->result = SAM_STAT_CHECK_CONDITION;
635 		cmnd->scsi_done(cmnd);
636 		return 0;
637 	}
638 
639 	spin_lock_irqsave(&devinfo->lock, flags);
640 
641 	if (devinfo->resetting) {
642 		cmnd->result = DID_ERROR << 16;
643 		cmnd->scsi_done(cmnd);
644 		spin_unlock_irqrestore(&devinfo->lock, flags);
645 		return 0;
646 	}
647 
648 	/* Find a free uas-tag */
649 	for (idx = 0; idx < devinfo->qdepth; idx++) {
650 		if (!devinfo->cmnd[idx])
651 			break;
652 	}
653 	if (idx == devinfo->qdepth) {
654 		spin_unlock_irqrestore(&devinfo->lock, flags);
655 		return SCSI_MLQUEUE_DEVICE_BUSY;
656 	}
657 
658 	cmnd->scsi_done = done;
659 
660 	memset(cmdinfo, 0, sizeof(*cmdinfo));
661 	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
662 	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
663 
664 	switch (cmnd->sc_data_direction) {
665 	case DMA_FROM_DEVICE:
666 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
667 		break;
668 	case DMA_BIDIRECTIONAL:
669 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
670 		/* fall through */
671 	case DMA_TO_DEVICE:
672 		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
673 	case DMA_NONE:
674 		break;
675 	}
676 
677 	if (!devinfo->use_streams)
678 		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
679 
680 	err = uas_submit_urbs(cmnd, devinfo);
681 	if (err) {
682 		/* If we did nothing, give up now */
683 		if (cmdinfo->state & SUBMIT_STATUS_URB) {
684 			spin_unlock_irqrestore(&devinfo->lock, flags);
685 			return SCSI_MLQUEUE_DEVICE_BUSY;
686 		}
687 		uas_add_work(cmdinfo);
688 	}
689 
690 	devinfo->cmnd[idx] = cmnd;
691 	spin_unlock_irqrestore(&devinfo->lock, flags);
692 	return 0;
693 }
694 
695 static DEF_SCSI_QCMD(uas_queuecommand)
696 
697 /*
698  * For now we do not support actually sending an abort to the device, so
699  * this eh always fails. Still we must define it to make sure that we've
700  * dropped all references to the cmnd in question once this function exits.
701  */
702 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
703 {
704 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
705 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
706 	struct urb *data_in_urb = NULL;
707 	struct urb *data_out_urb = NULL;
708 	unsigned long flags;
709 
710 	spin_lock_irqsave(&devinfo->lock, flags);
711 
712 	uas_log_cmd_state(cmnd, __func__, 0);
713 
714 	/* Ensure that try_complete does not call scsi_done */
715 	cmdinfo->state |= COMMAND_ABORTED;
716 
717 	/* Drop all refs to this cmnd, kill data urbs to break their ref */
718 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
719 	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
720 		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
721 	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
722 		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
723 
724 	uas_free_unsubmitted_urbs(cmnd);
725 
726 	spin_unlock_irqrestore(&devinfo->lock, flags);
727 
728 	if (data_in_urb) {
729 		usb_kill_urb(data_in_urb);
730 		usb_put_urb(data_in_urb);
731 	}
732 	if (data_out_urb) {
733 		usb_kill_urb(data_out_urb);
734 		usb_put_urb(data_out_urb);
735 	}
736 
737 	return FAILED;
738 }
739 
740 static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
741 {
742 	struct scsi_device *sdev = cmnd->device;
743 	struct uas_dev_info *devinfo = sdev->hostdata;
744 	struct usb_device *udev = devinfo->udev;
745 	unsigned long flags;
746 	int err;
747 
748 	err = usb_lock_device_for_reset(udev, devinfo->intf);
749 	if (err) {
750 		shost_printk(KERN_ERR, sdev->host,
751 			     "%s FAILED to get lock err %d\n", __func__, err);
752 		return FAILED;
753 	}
754 
755 	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
756 
757 	spin_lock_irqsave(&devinfo->lock, flags);
758 	devinfo->resetting = 1;
759 	spin_unlock_irqrestore(&devinfo->lock, flags);
760 
761 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
762 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
763 	usb_kill_anchored_urbs(&devinfo->data_urbs);
764 	uas_zap_pending(devinfo, DID_RESET);
765 
766 	err = usb_reset_device(udev);
767 
768 	spin_lock_irqsave(&devinfo->lock, flags);
769 	devinfo->resetting = 0;
770 	spin_unlock_irqrestore(&devinfo->lock, flags);
771 
772 	usb_unlock_device(udev);
773 
774 	if (err) {
775 		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
776 			     __func__, err);
777 		return FAILED;
778 	}
779 
780 	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
781 	return SUCCESS;
782 }
783 
784 static int uas_target_alloc(struct scsi_target *starget)
785 {
786 	struct uas_dev_info *devinfo = (struct uas_dev_info *)
787 			dev_to_shost(starget->dev.parent)->hostdata;
788 
789 	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
790 		starget->no_report_luns = 1;
791 
792 	return 0;
793 }
794 
795 static int uas_slave_alloc(struct scsi_device *sdev)
796 {
797 	struct uas_dev_info *devinfo =
798 		(struct uas_dev_info *)sdev->host->hostdata;
799 
800 	sdev->hostdata = devinfo;
801 
802 	/*
803 	 * USB has unusual DMA-alignment requirements: Although the
804 	 * starting address of each scatter-gather element doesn't matter,
805 	 * the length of each element except the last must be divisible
806 	 * by the Bulk maxpacket value.  There's currently no way to
807 	 * express this by block-layer constraints, so we'll cop out
808 	 * and simply require addresses to be aligned at 512-byte
809 	 * boundaries.  This is okay since most block I/O involves
810 	 * hardware sectors that are multiples of 512 bytes in length,
811 	 * and since host controllers up through USB 2.0 have maxpacket
812 	 * values no larger than 512.
813 	 *
814 	 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
815 	 * values can be as large as 2048.  To make that work properly
816 	 * will require changes to the block layer.
817 	 */
818 	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
819 
820 	if (devinfo->flags & US_FL_MAX_SECTORS_64)
821 		blk_queue_max_hw_sectors(sdev->request_queue, 64);
822 	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
823 		blk_queue_max_hw_sectors(sdev->request_queue, 240);
824 
825 	return 0;
826 }
827 
828 static int uas_slave_configure(struct scsi_device *sdev)
829 {
830 	struct uas_dev_info *devinfo = sdev->hostdata;
831 
832 	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
833 		sdev->no_report_opcodes = 1;
834 
835 	/* A few buggy USB-ATA bridges don't understand FUA */
836 	if (devinfo->flags & US_FL_BROKEN_FUA)
837 		sdev->broken_fua = 1;
838 
839 	/* UAS also needs to support FL_ALWAYS_SYNC */
840 	if (devinfo->flags & US_FL_ALWAYS_SYNC) {
841 		sdev->skip_ms_page_3f = 1;
842 		sdev->skip_ms_page_8 = 1;
843 		sdev->wce_default_on = 1;
844 	}
845 	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
846 	return 0;
847 }
848 
849 static struct scsi_host_template uas_host_template = {
850 	.module = THIS_MODULE,
851 	.name = "uas",
852 	.queuecommand = uas_queuecommand,
853 	.target_alloc = uas_target_alloc,
854 	.slave_alloc = uas_slave_alloc,
855 	.slave_configure = uas_slave_configure,
856 	.eh_abort_handler = uas_eh_abort_handler,
857 	.eh_device_reset_handler = uas_eh_device_reset_handler,
858 	.this_id = -1,
859 	.sg_tablesize = SG_NONE,
860 	.skip_settle_delay = 1,
861 };
862 
863 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
864 		    vendorName, productName, useProtocol, useTransport, \
865 		    initFunction, flags) \
866 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
867 	.driver_info = (flags) }
868 
869 static struct usb_device_id uas_usb_ids[] = {
870 #	include "unusual_uas.h"
871 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
872 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
873 	{ }
874 };
875 MODULE_DEVICE_TABLE(usb, uas_usb_ids);
876 
877 #undef UNUSUAL_DEV
878 
879 static int uas_switch_interface(struct usb_device *udev,
880 				struct usb_interface *intf)
881 {
882 	struct usb_host_interface *alt;
883 
884 	alt = uas_find_uas_alt_setting(intf);
885 	if (!alt)
886 		return -ENODEV;
887 
888 	return usb_set_interface(udev, alt->desc.bInterfaceNumber,
889 			alt->desc.bAlternateSetting);
890 }
891 
892 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
893 {
894 	struct usb_host_endpoint *eps[4] = { };
895 	struct usb_device *udev = devinfo->udev;
896 	int r;
897 
898 	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
899 	if (r)
900 		return r;
901 
902 	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
903 					    usb_endpoint_num(&eps[0]->desc));
904 	devinfo->status_pipe = usb_rcvbulkpipe(udev,
905 					    usb_endpoint_num(&eps[1]->desc));
906 	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
907 					    usb_endpoint_num(&eps[2]->desc));
908 	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
909 					    usb_endpoint_num(&eps[3]->desc));
910 
911 	if (udev->speed < USB_SPEED_SUPER) {
912 		devinfo->qdepth = 32;
913 		devinfo->use_streams = 0;
914 	} else {
915 		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
916 						    3, MAX_CMNDS, GFP_NOIO);
917 		if (devinfo->qdepth < 0)
918 			return devinfo->qdepth;
919 		devinfo->use_streams = 1;
920 	}
921 
922 	return 0;
923 }
924 
925 static void uas_free_streams(struct uas_dev_info *devinfo)
926 {
927 	struct usb_device *udev = devinfo->udev;
928 	struct usb_host_endpoint *eps[3];
929 
930 	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
931 	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
932 	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
933 	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
934 }
935 
936 static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
937 {
938 	int result = -ENOMEM;
939 	struct Scsi_Host *shost = NULL;
940 	struct uas_dev_info *devinfo;
941 	struct usb_device *udev = interface_to_usbdev(intf);
942 	unsigned long dev_flags;
943 
944 	if (!uas_use_uas_driver(intf, id, &dev_flags))
945 		return -ENODEV;
946 
947 	if (uas_switch_interface(udev, intf))
948 		return -ENODEV;
949 
950 	shost = scsi_host_alloc(&uas_host_template,
951 				sizeof(struct uas_dev_info));
952 	if (!shost)
953 		goto set_alt0;
954 
955 	shost->max_cmd_len = 16 + 252;
956 	shost->max_id = 1;
957 	shost->max_lun = 256;
958 	shost->max_channel = 0;
959 	shost->sg_tablesize = udev->bus->sg_tablesize;
960 
961 	devinfo = (struct uas_dev_info *)shost->hostdata;
962 	devinfo->intf = intf;
963 	devinfo->udev = udev;
964 	devinfo->resetting = 0;
965 	devinfo->shutdown = 0;
966 	devinfo->flags = dev_flags;
967 	init_usb_anchor(&devinfo->cmd_urbs);
968 	init_usb_anchor(&devinfo->sense_urbs);
969 	init_usb_anchor(&devinfo->data_urbs);
970 	spin_lock_init(&devinfo->lock);
971 	INIT_WORK(&devinfo->work, uas_do_work);
972 
973 	result = uas_configure_endpoints(devinfo);
974 	if (result)
975 		goto set_alt0;
976 
977 	/*
978 	 * 1 tag is reserved for untagged commands +
979 	 * 1 tag to avoid off by one errors in some bridge firmwares
980 	 */
981 	shost->can_queue = devinfo->qdepth - 2;
982 
983 	usb_set_intfdata(intf, shost);
984 	result = scsi_add_host(shost, &intf->dev);
985 	if (result)
986 		goto free_streams;
987 
988 	scsi_scan_host(shost);
989 	return result;
990 
991 free_streams:
992 	uas_free_streams(devinfo);
993 	usb_set_intfdata(intf, NULL);
994 set_alt0:
995 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
996 	if (shost)
997 		scsi_host_put(shost);
998 	return result;
999 }
1000 
1001 static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
1002 {
1003 	unsigned long flags;
1004 	int i, r = 1;
1005 
1006 	spin_lock_irqsave(&devinfo->lock, flags);
1007 
1008 	for (i = 0; i < devinfo->qdepth; i++) {
1009 		if (devinfo->cmnd[i]) {
1010 			r = 0; /* Not empty */
1011 			break;
1012 		}
1013 	}
1014 
1015 	spin_unlock_irqrestore(&devinfo->lock, flags);
1016 
1017 	return r;
1018 }
1019 
1020 /*
1021  * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
1022  * get empty while there still is more work to do due to sense-urbs completing
1023  * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
1024  */
1025 static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
1026 {
1027 	unsigned long start_time;
1028 	int r;
1029 
1030 	start_time = jiffies;
1031 	do {
1032 		flush_work(&devinfo->work);
1033 
1034 		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1035 		if (r == 0)
1036 			return -ETIME;
1037 
1038 		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1039 		if (r == 0)
1040 			return -ETIME;
1041 
1042 		if (time_after(jiffies, start_time + 5 * HZ))
1043 			return -ETIME;
1044 	} while (!uas_cmnd_list_empty(devinfo));
1045 
1046 	return 0;
1047 }
1048 
1049 static int uas_pre_reset(struct usb_interface *intf)
1050 {
1051 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1052 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1053 	unsigned long flags;
1054 
1055 	if (devinfo->shutdown)
1056 		return 0;
1057 
1058 	/* Block new requests */
1059 	spin_lock_irqsave(shost->host_lock, flags);
1060 	scsi_block_requests(shost);
1061 	spin_unlock_irqrestore(shost->host_lock, flags);
1062 
1063 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1064 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1065 		scsi_unblock_requests(shost);
1066 		return 1;
1067 	}
1068 
1069 	uas_free_streams(devinfo);
1070 
1071 	return 0;
1072 }
1073 
1074 static int uas_post_reset(struct usb_interface *intf)
1075 {
1076 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1077 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1078 	unsigned long flags;
1079 	int err;
1080 
1081 	if (devinfo->shutdown)
1082 		return 0;
1083 
1084 	err = uas_configure_endpoints(devinfo);
1085 	if (err && err != -ENODEV)
1086 		shost_printk(KERN_ERR, shost,
1087 			     "%s: alloc streams error %d after reset",
1088 			     __func__, err);
1089 
1090 	/* we must unblock the host in every case lest we deadlock */
1091 	spin_lock_irqsave(shost->host_lock, flags);
1092 	scsi_report_bus_reset(shost, 0);
1093 	spin_unlock_irqrestore(shost->host_lock, flags);
1094 
1095 	scsi_unblock_requests(shost);
1096 
1097 	return err ? 1 : 0;
1098 }
1099 
1100 static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1101 {
1102 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1103 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1104 
1105 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1106 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1107 		return -ETIME;
1108 	}
1109 
1110 	return 0;
1111 }
1112 
1113 static int uas_resume(struct usb_interface *intf)
1114 {
1115 	return 0;
1116 }
1117 
1118 static int uas_reset_resume(struct usb_interface *intf)
1119 {
1120 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1121 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1122 	unsigned long flags;
1123 	int err;
1124 
1125 	err = uas_configure_endpoints(devinfo);
1126 	if (err) {
1127 		shost_printk(KERN_ERR, shost,
1128 			     "%s: alloc streams error %d after reset",
1129 			     __func__, err);
1130 		return -EIO;
1131 	}
1132 
1133 	spin_lock_irqsave(shost->host_lock, flags);
1134 	scsi_report_bus_reset(shost, 0);
1135 	spin_unlock_irqrestore(shost->host_lock, flags);
1136 
1137 	return 0;
1138 }
1139 
1140 static void uas_disconnect(struct usb_interface *intf)
1141 {
1142 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1143 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1144 	unsigned long flags;
1145 
1146 	spin_lock_irqsave(&devinfo->lock, flags);
1147 	devinfo->resetting = 1;
1148 	spin_unlock_irqrestore(&devinfo->lock, flags);
1149 
1150 	cancel_work_sync(&devinfo->work);
1151 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1152 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
1153 	usb_kill_anchored_urbs(&devinfo->data_urbs);
1154 	uas_zap_pending(devinfo, DID_NO_CONNECT);
1155 
1156 	scsi_remove_host(shost);
1157 	uas_free_streams(devinfo);
1158 	scsi_host_put(shost);
1159 }
1160 
1161 /*
1162  * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1163  * hang on reboot when the device is still in uas mode. Note the reset is
1164  * necessary as some devices won't revert to usb-storage mode without it.
1165  */
1166 static void uas_shutdown(struct device *dev)
1167 {
1168 	struct usb_interface *intf = to_usb_interface(dev);
1169 	struct usb_device *udev = interface_to_usbdev(intf);
1170 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1171 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1172 
1173 	if (system_state != SYSTEM_RESTART)
1174 		return;
1175 
1176 	devinfo->shutdown = 1;
1177 	uas_free_streams(devinfo);
1178 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1179 	usb_reset_device(udev);
1180 }
1181 
1182 static struct usb_driver uas_driver = {
1183 	.name = "uas",
1184 	.probe = uas_probe,
1185 	.disconnect = uas_disconnect,
1186 	.pre_reset = uas_pre_reset,
1187 	.post_reset = uas_post_reset,
1188 	.suspend = uas_suspend,
1189 	.resume = uas_resume,
1190 	.reset_resume = uas_reset_resume,
1191 	.drvwrap.driver.shutdown = uas_shutdown,
1192 	.id_table = uas_usb_ids,
1193 };
1194 
1195 module_usb_driver(uas_driver);
1196 
1197 MODULE_LICENSE("GPL");
1198 MODULE_AUTHOR(
1199 	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");
1200