xref: /linux/drivers/usb/storage/uas.c (revision 5fd54ace4721fc5ce2bb5aef6318fcf17f421460)
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  * Distributed under the terms of the GNU GPL, version two.
11  */
12 
13 #include <linux/blkdev.h>
14 #include <linux/slab.h>
15 #include <linux/types.h>
16 #include <linux/module.h>
17 #include <linux/usb.h>
18 #include <linux/usb_usual.h>
19 #include <linux/usb/hcd.h>
20 #include <linux/usb/storage.h>
21 #include <linux/usb/uas.h>
22 
23 #include <scsi/scsi.h>
24 #include <scsi/scsi_eh.h>
25 #include <scsi/scsi_dbg.h>
26 #include <scsi/scsi_cmnd.h>
27 #include <scsi/scsi_device.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_tcq.h>
30 
31 #include "uas-detect.h"
32 #include "scsiglue.h"
33 
34 #define MAX_CMNDS 256
35 
36 struct uas_dev_info {
37 	struct usb_interface *intf;
38 	struct usb_device *udev;
39 	struct usb_anchor cmd_urbs;
40 	struct usb_anchor sense_urbs;
41 	struct usb_anchor data_urbs;
42 	unsigned long flags;
43 	int qdepth, resetting;
44 	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
45 	unsigned use_streams:1;
46 	unsigned shutdown:1;
47 	struct scsi_cmnd *cmnd[MAX_CMNDS];
48 	spinlock_t lock;
49 	struct work_struct work;
50 };
51 
52 enum {
53 	SUBMIT_STATUS_URB	= BIT(1),
54 	ALLOC_DATA_IN_URB	= BIT(2),
55 	SUBMIT_DATA_IN_URB	= BIT(3),
56 	ALLOC_DATA_OUT_URB	= BIT(4),
57 	SUBMIT_DATA_OUT_URB	= BIT(5),
58 	ALLOC_CMD_URB		= BIT(6),
59 	SUBMIT_CMD_URB		= BIT(7),
60 	COMMAND_INFLIGHT        = BIT(8),
61 	DATA_IN_URB_INFLIGHT    = BIT(9),
62 	DATA_OUT_URB_INFLIGHT   = BIT(10),
63 	COMMAND_ABORTED         = BIT(11),
64 	IS_IN_WORK_LIST         = BIT(12),
65 };
66 
67 /* Overrides scsi_pointer */
68 struct uas_cmd_info {
69 	unsigned int state;
70 	unsigned int uas_tag;
71 	struct urb *cmd_urb;
72 	struct urb *data_in_urb;
73 	struct urb *data_out_urb;
74 };
75 
76 /* I hate forward declarations, but I actually have a loop */
77 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
78 				struct uas_dev_info *devinfo);
79 static void uas_do_work(struct work_struct *work);
80 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller);
81 static void uas_free_streams(struct uas_dev_info *devinfo);
82 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
83 				int status);
84 
85 static void uas_do_work(struct work_struct *work)
86 {
87 	struct uas_dev_info *devinfo =
88 		container_of(work, struct uas_dev_info, work);
89 	struct uas_cmd_info *cmdinfo;
90 	struct scsi_cmnd *cmnd;
91 	unsigned long flags;
92 	int i, err;
93 
94 	spin_lock_irqsave(&devinfo->lock, flags);
95 
96 	if (devinfo->resetting)
97 		goto out;
98 
99 	for (i = 0; i < devinfo->qdepth; i++) {
100 		if (!devinfo->cmnd[i])
101 			continue;
102 
103 		cmnd = devinfo->cmnd[i];
104 		cmdinfo = (void *)&cmnd->SCp;
105 
106 		if (!(cmdinfo->state & IS_IN_WORK_LIST))
107 			continue;
108 
109 		err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
110 		if (!err)
111 			cmdinfo->state &= ~IS_IN_WORK_LIST;
112 		else
113 			schedule_work(&devinfo->work);
114 	}
115 out:
116 	spin_unlock_irqrestore(&devinfo->lock, flags);
117 }
118 
119 static void uas_add_work(struct uas_cmd_info *cmdinfo)
120 {
121 	struct scsi_pointer *scp = (void *)cmdinfo;
122 	struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
123 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
124 
125 	lockdep_assert_held(&devinfo->lock);
126 	cmdinfo->state |= IS_IN_WORK_LIST;
127 	schedule_work(&devinfo->work);
128 }
129 
130 static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
131 {
132 	struct uas_cmd_info *cmdinfo;
133 	struct scsi_cmnd *cmnd;
134 	unsigned long flags;
135 	int i, err;
136 
137 	spin_lock_irqsave(&devinfo->lock, flags);
138 	for (i = 0; i < devinfo->qdepth; i++) {
139 		if (!devinfo->cmnd[i])
140 			continue;
141 
142 		cmnd = devinfo->cmnd[i];
143 		cmdinfo = (void *)&cmnd->SCp;
144 		uas_log_cmd_state(cmnd, __func__, 0);
145 		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
146 		cmdinfo->state &= ~COMMAND_INFLIGHT;
147 		cmnd->result = result << 16;
148 		err = uas_try_complete(cmnd, __func__);
149 		WARN_ON(err != 0);
150 	}
151 	spin_unlock_irqrestore(&devinfo->lock, flags);
152 }
153 
154 static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
155 {
156 	struct sense_iu *sense_iu = urb->transfer_buffer;
157 	struct scsi_device *sdev = cmnd->device;
158 
159 	if (urb->actual_length > 16) {
160 		unsigned len = be16_to_cpup(&sense_iu->len);
161 		if (len + 16 != urb->actual_length) {
162 			int newlen = min(len + 16, urb->actual_length) - 16;
163 			if (newlen < 0)
164 				newlen = 0;
165 			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
166 				"disagrees with IU sense data length %d, "
167 				"using %d bytes of sense data\n", __func__,
168 					urb->actual_length, len, newlen);
169 			len = newlen;
170 		}
171 		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
172 	}
173 
174 	cmnd->result = sense_iu->status;
175 }
176 
177 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
178 			      int status)
179 {
180 	struct uas_cmd_info *ci = (void *)&cmnd->SCp;
181 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
182 
183 	scmd_printk(KERN_INFO, cmnd,
184 		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
185 		    prefix, status, cmdinfo->uas_tag,
186 		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
187 		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
188 		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
189 		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
190 		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
191 		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
192 		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
193 		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
194 		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
195 		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
196 		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
197 		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
198 	scsi_print_command(cmnd);
199 }
200 
201 static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
202 {
203 	struct uas_cmd_info *cmdinfo;
204 
205 	if (!cmnd)
206 		return;
207 
208 	cmdinfo = (void *)&cmnd->SCp;
209 
210 	if (cmdinfo->state & SUBMIT_CMD_URB)
211 		usb_free_urb(cmdinfo->cmd_urb);
212 
213 	/* data urbs may have never gotten their submit flag set */
214 	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
215 		usb_free_urb(cmdinfo->data_in_urb);
216 	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
217 		usb_free_urb(cmdinfo->data_out_urb);
218 }
219 
220 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
221 {
222 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
223 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
224 
225 	lockdep_assert_held(&devinfo->lock);
226 	if (cmdinfo->state & (COMMAND_INFLIGHT |
227 			      DATA_IN_URB_INFLIGHT |
228 			      DATA_OUT_URB_INFLIGHT |
229 			      COMMAND_ABORTED))
230 		return -EBUSY;
231 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
232 	uas_free_unsubmitted_urbs(cmnd);
233 	cmnd->scsi_done(cmnd);
234 	return 0;
235 }
236 
237 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
238 			  unsigned direction)
239 {
240 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
241 	int err;
242 
243 	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
244 	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
245 	if (err) {
246 		uas_add_work(cmdinfo);
247 	}
248 }
249 
250 static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
251 {
252 	u8 response_code = riu->response_code;
253 
254 	switch (response_code) {
255 	case RC_INCORRECT_LUN:
256 		cmnd->result = DID_BAD_TARGET << 16;
257 		break;
258 	case RC_TMF_SUCCEEDED:
259 		cmnd->result = DID_OK << 16;
260 		break;
261 	case RC_TMF_NOT_SUPPORTED:
262 		cmnd->result = DID_TARGET_FAILURE << 16;
263 		break;
264 	default:
265 		uas_log_cmd_state(cmnd, "response iu", response_code);
266 		cmnd->result = DID_ERROR << 16;
267 		break;
268 	}
269 
270 	return response_code == RC_TMF_SUCCEEDED;
271 }
272 
273 static void uas_stat_cmplt(struct urb *urb)
274 {
275 	struct iu *iu = urb->transfer_buffer;
276 	struct Scsi_Host *shost = urb->context;
277 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
278 	struct urb *data_in_urb = NULL;
279 	struct urb *data_out_urb = NULL;
280 	struct scsi_cmnd *cmnd;
281 	struct uas_cmd_info *cmdinfo;
282 	unsigned long flags;
283 	unsigned int idx;
284 	int status = urb->status;
285 	bool success;
286 
287 	spin_lock_irqsave(&devinfo->lock, flags);
288 
289 	if (devinfo->resetting)
290 		goto out;
291 
292 	if (status) {
293 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
294 			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
295 		goto out;
296 	}
297 
298 	idx = be16_to_cpup(&iu->tag) - 1;
299 	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
300 		dev_err(&urb->dev->dev,
301 			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
302 		goto out;
303 	}
304 
305 	cmnd = devinfo->cmnd[idx];
306 	cmdinfo = (void *)&cmnd->SCp;
307 
308 	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
309 		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
310 		goto out;
311 	}
312 
313 	switch (iu->iu_id) {
314 	case IU_ID_STATUS:
315 		uas_sense(urb, cmnd);
316 		if (cmnd->result != 0) {
317 			/* cancel data transfers on error */
318 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
319 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
320 		}
321 		cmdinfo->state &= ~COMMAND_INFLIGHT;
322 		uas_try_complete(cmnd, __func__);
323 		break;
324 	case IU_ID_READ_READY:
325 		if (!cmdinfo->data_in_urb ||
326 				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
327 			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
328 			break;
329 		}
330 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
331 		break;
332 	case IU_ID_WRITE_READY:
333 		if (!cmdinfo->data_out_urb ||
334 				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
335 			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
336 			break;
337 		}
338 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
339 		break;
340 	case IU_ID_RESPONSE:
341 		cmdinfo->state &= ~COMMAND_INFLIGHT;
342 		success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
343 		if (!success) {
344 			/* Error, cancel data transfers */
345 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
346 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
347 		}
348 		uas_try_complete(cmnd, __func__);
349 		break;
350 	default:
351 		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
352 	}
353 out:
354 	usb_free_urb(urb);
355 	spin_unlock_irqrestore(&devinfo->lock, flags);
356 
357 	/* Unlinking of data urbs must be done without holding the lock */
358 	if (data_in_urb) {
359 		usb_unlink_urb(data_in_urb);
360 		usb_put_urb(data_in_urb);
361 	}
362 	if (data_out_urb) {
363 		usb_unlink_urb(data_out_urb);
364 		usb_put_urb(data_out_urb);
365 	}
366 }
367 
368 static void uas_data_cmplt(struct urb *urb)
369 {
370 	struct scsi_cmnd *cmnd = urb->context;
371 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
372 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
373 	struct scsi_data_buffer *sdb = NULL;
374 	unsigned long flags;
375 	int status = urb->status;
376 
377 	spin_lock_irqsave(&devinfo->lock, flags);
378 
379 	if (cmdinfo->data_in_urb == urb) {
380 		sdb = scsi_in(cmnd);
381 		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
382 		cmdinfo->data_in_urb = NULL;
383 	} else if (cmdinfo->data_out_urb == urb) {
384 		sdb = scsi_out(cmnd);
385 		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
386 		cmdinfo->data_out_urb = NULL;
387 	}
388 	if (sdb == NULL) {
389 		WARN_ON_ONCE(1);
390 		goto out;
391 	}
392 
393 	if (devinfo->resetting)
394 		goto out;
395 
396 	/* Data urbs should not complete before the cmd urb is submitted */
397 	if (cmdinfo->state & SUBMIT_CMD_URB) {
398 		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
399 		goto out;
400 	}
401 
402 	if (status) {
403 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
404 			uas_log_cmd_state(cmnd, "data cmplt err", status);
405 		/* error: no data transfered */
406 		sdb->resid = sdb->length;
407 	} else {
408 		sdb->resid = sdb->length - urb->actual_length;
409 	}
410 	uas_try_complete(cmnd, __func__);
411 out:
412 	usb_free_urb(urb);
413 	spin_unlock_irqrestore(&devinfo->lock, flags);
414 }
415 
416 static void uas_cmd_cmplt(struct urb *urb)
417 {
418 	if (urb->status)
419 		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
420 
421 	usb_free_urb(urb);
422 }
423 
424 static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
425 				      struct scsi_cmnd *cmnd,
426 				      enum dma_data_direction dir)
427 {
428 	struct usb_device *udev = devinfo->udev;
429 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
430 	struct urb *urb = usb_alloc_urb(0, gfp);
431 	struct scsi_data_buffer *sdb = (dir == DMA_FROM_DEVICE)
432 		? scsi_in(cmnd) : scsi_out(cmnd);
433 	unsigned int pipe = (dir == DMA_FROM_DEVICE)
434 		? devinfo->data_in_pipe : devinfo->data_out_pipe;
435 
436 	if (!urb)
437 		goto out;
438 	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
439 			  uas_data_cmplt, cmnd);
440 	if (devinfo->use_streams)
441 		urb->stream_id = cmdinfo->uas_tag;
442 	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
443 	urb->sg = sdb->table.sgl;
444  out:
445 	return urb;
446 }
447 
448 static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
449 				       struct scsi_cmnd *cmnd)
450 {
451 	struct usb_device *udev = devinfo->udev;
452 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
453 	struct urb *urb = usb_alloc_urb(0, gfp);
454 	struct sense_iu *iu;
455 
456 	if (!urb)
457 		goto out;
458 
459 	iu = kzalloc(sizeof(*iu), gfp);
460 	if (!iu)
461 		goto free;
462 
463 	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
464 			  uas_stat_cmplt, cmnd->device->host);
465 	if (devinfo->use_streams)
466 		urb->stream_id = cmdinfo->uas_tag;
467 	urb->transfer_flags |= URB_FREE_BUFFER;
468  out:
469 	return urb;
470  free:
471 	usb_free_urb(urb);
472 	return NULL;
473 }
474 
475 static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
476 					struct scsi_cmnd *cmnd)
477 {
478 	struct usb_device *udev = devinfo->udev;
479 	struct scsi_device *sdev = cmnd->device;
480 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
481 	struct urb *urb = usb_alloc_urb(0, gfp);
482 	struct command_iu *iu;
483 	int len;
484 
485 	if (!urb)
486 		goto out;
487 
488 	len = cmnd->cmd_len - 16;
489 	if (len < 0)
490 		len = 0;
491 	len = ALIGN(len, 4);
492 	iu = kzalloc(sizeof(*iu) + len, gfp);
493 	if (!iu)
494 		goto free;
495 
496 	iu->iu_id = IU_ID_COMMAND;
497 	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
498 	iu->prio_attr = UAS_SIMPLE_TAG;
499 	iu->len = len;
500 	int_to_scsilun(sdev->lun, &iu->lun);
501 	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
502 
503 	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
504 							uas_cmd_cmplt, NULL);
505 	urb->transfer_flags |= URB_FREE_BUFFER;
506  out:
507 	return urb;
508  free:
509 	usb_free_urb(urb);
510 	return NULL;
511 }
512 
513 /*
514  * Why should I request the Status IU before sending the Command IU?  Spec
515  * says to, but also says the device may receive them in any order.  Seems
516  * daft to me.
517  */
518 
519 static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
520 {
521 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
522 	struct urb *urb;
523 	int err;
524 
525 	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
526 	if (!urb)
527 		return NULL;
528 	usb_anchor_urb(urb, &devinfo->sense_urbs);
529 	err = usb_submit_urb(urb, gfp);
530 	if (err) {
531 		usb_unanchor_urb(urb);
532 		uas_log_cmd_state(cmnd, "sense submit err", err);
533 		usb_free_urb(urb);
534 		return NULL;
535 	}
536 	return urb;
537 }
538 
539 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
540 			   struct uas_dev_info *devinfo)
541 {
542 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
543 	struct urb *urb;
544 	int err;
545 
546 	lockdep_assert_held(&devinfo->lock);
547 	if (cmdinfo->state & SUBMIT_STATUS_URB) {
548 		urb = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
549 		if (!urb)
550 			return SCSI_MLQUEUE_DEVICE_BUSY;
551 		cmdinfo->state &= ~SUBMIT_STATUS_URB;
552 	}
553 
554 	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
555 		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
556 							cmnd, DMA_FROM_DEVICE);
557 		if (!cmdinfo->data_in_urb)
558 			return SCSI_MLQUEUE_DEVICE_BUSY;
559 		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
560 	}
561 
562 	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
563 		usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
564 		err = usb_submit_urb(cmdinfo->data_in_urb, GFP_ATOMIC);
565 		if (err) {
566 			usb_unanchor_urb(cmdinfo->data_in_urb);
567 			uas_log_cmd_state(cmnd, "data in submit err", err);
568 			return SCSI_MLQUEUE_DEVICE_BUSY;
569 		}
570 		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
571 		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
572 	}
573 
574 	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
575 		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
576 							cmnd, DMA_TO_DEVICE);
577 		if (!cmdinfo->data_out_urb)
578 			return SCSI_MLQUEUE_DEVICE_BUSY;
579 		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
580 	}
581 
582 	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
583 		usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
584 		err = usb_submit_urb(cmdinfo->data_out_urb, GFP_ATOMIC);
585 		if (err) {
586 			usb_unanchor_urb(cmdinfo->data_out_urb);
587 			uas_log_cmd_state(cmnd, "data out submit err", err);
588 			return SCSI_MLQUEUE_DEVICE_BUSY;
589 		}
590 		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
591 		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
592 	}
593 
594 	if (cmdinfo->state & ALLOC_CMD_URB) {
595 		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
596 		if (!cmdinfo->cmd_urb)
597 			return SCSI_MLQUEUE_DEVICE_BUSY;
598 		cmdinfo->state &= ~ALLOC_CMD_URB;
599 	}
600 
601 	if (cmdinfo->state & SUBMIT_CMD_URB) {
602 		usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
603 		err = usb_submit_urb(cmdinfo->cmd_urb, GFP_ATOMIC);
604 		if (err) {
605 			usb_unanchor_urb(cmdinfo->cmd_urb);
606 			uas_log_cmd_state(cmnd, "cmd submit err", err);
607 			return SCSI_MLQUEUE_DEVICE_BUSY;
608 		}
609 		cmdinfo->cmd_urb = NULL;
610 		cmdinfo->state &= ~SUBMIT_CMD_URB;
611 		cmdinfo->state |= COMMAND_INFLIGHT;
612 	}
613 
614 	return 0;
615 }
616 
617 static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
618 					void (*done)(struct scsi_cmnd *))
619 {
620 	struct scsi_device *sdev = cmnd->device;
621 	struct uas_dev_info *devinfo = sdev->hostdata;
622 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
623 	unsigned long flags;
624 	int idx, err;
625 
626 	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
627 
628 	/* Re-check scsi_block_requests now that we've the host-lock */
629 	if (cmnd->device->host->host_self_blocked)
630 		return SCSI_MLQUEUE_DEVICE_BUSY;
631 
632 	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
633 			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
634 		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
635 		       sizeof(usb_stor_sense_invalidCDB));
636 		cmnd->result = SAM_STAT_CHECK_CONDITION;
637 		cmnd->scsi_done(cmnd);
638 		return 0;
639 	}
640 
641 	spin_lock_irqsave(&devinfo->lock, flags);
642 
643 	if (devinfo->resetting) {
644 		cmnd->result = DID_ERROR << 16;
645 		cmnd->scsi_done(cmnd);
646 		spin_unlock_irqrestore(&devinfo->lock, flags);
647 		return 0;
648 	}
649 
650 	/* Find a free uas-tag */
651 	for (idx = 0; idx < devinfo->qdepth; idx++) {
652 		if (!devinfo->cmnd[idx])
653 			break;
654 	}
655 	if (idx == devinfo->qdepth) {
656 		spin_unlock_irqrestore(&devinfo->lock, flags);
657 		return SCSI_MLQUEUE_DEVICE_BUSY;
658 	}
659 
660 	cmnd->scsi_done = done;
661 
662 	memset(cmdinfo, 0, sizeof(*cmdinfo));
663 	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
664 	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
665 
666 	switch (cmnd->sc_data_direction) {
667 	case DMA_FROM_DEVICE:
668 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
669 		break;
670 	case DMA_BIDIRECTIONAL:
671 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
672 		/* fall through */
673 	case DMA_TO_DEVICE:
674 		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
675 	case DMA_NONE:
676 		break;
677 	}
678 
679 	if (!devinfo->use_streams)
680 		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
681 
682 	err = uas_submit_urbs(cmnd, devinfo);
683 	if (err) {
684 		/* If we did nothing, give up now */
685 		if (cmdinfo->state & SUBMIT_STATUS_URB) {
686 			spin_unlock_irqrestore(&devinfo->lock, flags);
687 			return SCSI_MLQUEUE_DEVICE_BUSY;
688 		}
689 		uas_add_work(cmdinfo);
690 	}
691 
692 	devinfo->cmnd[idx] = cmnd;
693 	spin_unlock_irqrestore(&devinfo->lock, flags);
694 	return 0;
695 }
696 
697 static DEF_SCSI_QCMD(uas_queuecommand)
698 
699 /*
700  * For now we do not support actually sending an abort to the device, so
701  * this eh always fails. Still we must define it to make sure that we've
702  * dropped all references to the cmnd in question once this function exits.
703  */
704 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
705 {
706 	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
707 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
708 	struct urb *data_in_urb = NULL;
709 	struct urb *data_out_urb = NULL;
710 	unsigned long flags;
711 
712 	spin_lock_irqsave(&devinfo->lock, flags);
713 
714 	uas_log_cmd_state(cmnd, __func__, 0);
715 
716 	/* Ensure that try_complete does not call scsi_done */
717 	cmdinfo->state |= COMMAND_ABORTED;
718 
719 	/* Drop all refs to this cmnd, kill data urbs to break their ref */
720 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
721 	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
722 		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
723 	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
724 		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
725 
726 	uas_free_unsubmitted_urbs(cmnd);
727 
728 	spin_unlock_irqrestore(&devinfo->lock, flags);
729 
730 	if (data_in_urb) {
731 		usb_kill_urb(data_in_urb);
732 		usb_put_urb(data_in_urb);
733 	}
734 	if (data_out_urb) {
735 		usb_kill_urb(data_out_urb);
736 		usb_put_urb(data_out_urb);
737 	}
738 
739 	return FAILED;
740 }
741 
742 static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
743 {
744 	struct scsi_device *sdev = cmnd->device;
745 	struct uas_dev_info *devinfo = sdev->hostdata;
746 	struct usb_device *udev = devinfo->udev;
747 	unsigned long flags;
748 	int err;
749 
750 	err = usb_lock_device_for_reset(udev, devinfo->intf);
751 	if (err) {
752 		shost_printk(KERN_ERR, sdev->host,
753 			     "%s FAILED to get lock err %d\n", __func__, err);
754 		return FAILED;
755 	}
756 
757 	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
758 
759 	spin_lock_irqsave(&devinfo->lock, flags);
760 	devinfo->resetting = 1;
761 	spin_unlock_irqrestore(&devinfo->lock, flags);
762 
763 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
764 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
765 	usb_kill_anchored_urbs(&devinfo->data_urbs);
766 	uas_zap_pending(devinfo, DID_RESET);
767 
768 	err = usb_reset_device(udev);
769 
770 	spin_lock_irqsave(&devinfo->lock, flags);
771 	devinfo->resetting = 0;
772 	spin_unlock_irqrestore(&devinfo->lock, flags);
773 
774 	usb_unlock_device(udev);
775 
776 	if (err) {
777 		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
778 			     __func__, err);
779 		return FAILED;
780 	}
781 
782 	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
783 	return SUCCESS;
784 }
785 
786 static int uas_target_alloc(struct scsi_target *starget)
787 {
788 	struct uas_dev_info *devinfo = (struct uas_dev_info *)
789 			dev_to_shost(starget->dev.parent)->hostdata;
790 
791 	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
792 		starget->no_report_luns = 1;
793 
794 	return 0;
795 }
796 
797 static int uas_slave_alloc(struct scsi_device *sdev)
798 {
799 	struct uas_dev_info *devinfo =
800 		(struct uas_dev_info *)sdev->host->hostdata;
801 
802 	sdev->hostdata = devinfo;
803 
804 	/*
805 	 * USB has unusual DMA-alignment requirements: Although the
806 	 * starting address of each scatter-gather element doesn't matter,
807 	 * the length of each element except the last must be divisible
808 	 * by the Bulk maxpacket value.  There's currently no way to
809 	 * express this by block-layer constraints, so we'll cop out
810 	 * and simply require addresses to be aligned at 512-byte
811 	 * boundaries.  This is okay since most block I/O involves
812 	 * hardware sectors that are multiples of 512 bytes in length,
813 	 * and since host controllers up through USB 2.0 have maxpacket
814 	 * values no larger than 512.
815 	 *
816 	 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
817 	 * values can be as large as 2048.  To make that work properly
818 	 * will require changes to the block layer.
819 	 */
820 	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
821 
822 	if (devinfo->flags & US_FL_MAX_SECTORS_64)
823 		blk_queue_max_hw_sectors(sdev->request_queue, 64);
824 	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
825 		blk_queue_max_hw_sectors(sdev->request_queue, 240);
826 
827 	return 0;
828 }
829 
830 static int uas_slave_configure(struct scsi_device *sdev)
831 {
832 	struct uas_dev_info *devinfo = sdev->hostdata;
833 
834 	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
835 		sdev->no_report_opcodes = 1;
836 
837 	/* A few buggy USB-ATA bridges don't understand FUA */
838 	if (devinfo->flags & US_FL_BROKEN_FUA)
839 		sdev->broken_fua = 1;
840 
841 	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
842 	return 0;
843 }
844 
845 static struct scsi_host_template uas_host_template = {
846 	.module = THIS_MODULE,
847 	.name = "uas",
848 	.queuecommand = uas_queuecommand,
849 	.target_alloc = uas_target_alloc,
850 	.slave_alloc = uas_slave_alloc,
851 	.slave_configure = uas_slave_configure,
852 	.eh_abort_handler = uas_eh_abort_handler,
853 	.eh_device_reset_handler = uas_eh_device_reset_handler,
854 	.this_id = -1,
855 	.sg_tablesize = SG_NONE,
856 	.skip_settle_delay = 1,
857 };
858 
859 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
860 		    vendorName, productName, useProtocol, useTransport, \
861 		    initFunction, flags) \
862 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
863 	.driver_info = (flags) }
864 
865 static struct usb_device_id uas_usb_ids[] = {
866 #	include "unusual_uas.h"
867 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
868 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
869 	{ }
870 };
871 MODULE_DEVICE_TABLE(usb, uas_usb_ids);
872 
873 #undef UNUSUAL_DEV
874 
875 static int uas_switch_interface(struct usb_device *udev,
876 				struct usb_interface *intf)
877 {
878 	struct usb_host_interface *alt;
879 
880 	alt = uas_find_uas_alt_setting(intf);
881 	if (!alt)
882 		return -ENODEV;
883 
884 	return usb_set_interface(udev, alt->desc.bInterfaceNumber,
885 			alt->desc.bAlternateSetting);
886 }
887 
888 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
889 {
890 	struct usb_host_endpoint *eps[4] = { };
891 	struct usb_device *udev = devinfo->udev;
892 	int r;
893 
894 	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
895 	if (r)
896 		return r;
897 
898 	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
899 					    usb_endpoint_num(&eps[0]->desc));
900 	devinfo->status_pipe = usb_rcvbulkpipe(udev,
901 					    usb_endpoint_num(&eps[1]->desc));
902 	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
903 					    usb_endpoint_num(&eps[2]->desc));
904 	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
905 					    usb_endpoint_num(&eps[3]->desc));
906 
907 	if (udev->speed < USB_SPEED_SUPER) {
908 		devinfo->qdepth = 32;
909 		devinfo->use_streams = 0;
910 	} else {
911 		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
912 						    3, MAX_CMNDS, GFP_NOIO);
913 		if (devinfo->qdepth < 0)
914 			return devinfo->qdepth;
915 		devinfo->use_streams = 1;
916 	}
917 
918 	return 0;
919 }
920 
921 static void uas_free_streams(struct uas_dev_info *devinfo)
922 {
923 	struct usb_device *udev = devinfo->udev;
924 	struct usb_host_endpoint *eps[3];
925 
926 	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
927 	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
928 	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
929 	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
930 }
931 
932 static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
933 {
934 	int result = -ENOMEM;
935 	struct Scsi_Host *shost = NULL;
936 	struct uas_dev_info *devinfo;
937 	struct usb_device *udev = interface_to_usbdev(intf);
938 	unsigned long dev_flags;
939 
940 	if (!uas_use_uas_driver(intf, id, &dev_flags))
941 		return -ENODEV;
942 
943 	if (uas_switch_interface(udev, intf))
944 		return -ENODEV;
945 
946 	shost = scsi_host_alloc(&uas_host_template,
947 				sizeof(struct uas_dev_info));
948 	if (!shost)
949 		goto set_alt0;
950 
951 	shost->max_cmd_len = 16 + 252;
952 	shost->max_id = 1;
953 	shost->max_lun = 256;
954 	shost->max_channel = 0;
955 	shost->sg_tablesize = udev->bus->sg_tablesize;
956 
957 	devinfo = (struct uas_dev_info *)shost->hostdata;
958 	devinfo->intf = intf;
959 	devinfo->udev = udev;
960 	devinfo->resetting = 0;
961 	devinfo->shutdown = 0;
962 	devinfo->flags = dev_flags;
963 	init_usb_anchor(&devinfo->cmd_urbs);
964 	init_usb_anchor(&devinfo->sense_urbs);
965 	init_usb_anchor(&devinfo->data_urbs);
966 	spin_lock_init(&devinfo->lock);
967 	INIT_WORK(&devinfo->work, uas_do_work);
968 
969 	result = uas_configure_endpoints(devinfo);
970 	if (result)
971 		goto set_alt0;
972 
973 	/*
974 	 * 1 tag is reserved for untagged commands +
975 	 * 1 tag to avoid off by one errors in some bridge firmwares
976 	 */
977 	shost->can_queue = devinfo->qdepth - 2;
978 
979 	usb_set_intfdata(intf, shost);
980 	result = scsi_add_host(shost, &intf->dev);
981 	if (result)
982 		goto free_streams;
983 
984 	scsi_scan_host(shost);
985 	return result;
986 
987 free_streams:
988 	uas_free_streams(devinfo);
989 	usb_set_intfdata(intf, NULL);
990 set_alt0:
991 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
992 	if (shost)
993 		scsi_host_put(shost);
994 	return result;
995 }
996 
997 static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
998 {
999 	unsigned long flags;
1000 	int i, r = 1;
1001 
1002 	spin_lock_irqsave(&devinfo->lock, flags);
1003 
1004 	for (i = 0; i < devinfo->qdepth; i++) {
1005 		if (devinfo->cmnd[i]) {
1006 			r = 0; /* Not empty */
1007 			break;
1008 		}
1009 	}
1010 
1011 	spin_unlock_irqrestore(&devinfo->lock, flags);
1012 
1013 	return r;
1014 }
1015 
1016 /*
1017  * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
1018  * get empty while there still is more work to do due to sense-urbs completing
1019  * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
1020  */
1021 static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
1022 {
1023 	unsigned long start_time;
1024 	int r;
1025 
1026 	start_time = jiffies;
1027 	do {
1028 		flush_work(&devinfo->work);
1029 
1030 		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1031 		if (r == 0)
1032 			return -ETIME;
1033 
1034 		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1035 		if (r == 0)
1036 			return -ETIME;
1037 
1038 		if (time_after(jiffies, start_time + 5 * HZ))
1039 			return -ETIME;
1040 	} while (!uas_cmnd_list_empty(devinfo));
1041 
1042 	return 0;
1043 }
1044 
1045 static int uas_pre_reset(struct usb_interface *intf)
1046 {
1047 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1048 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1049 	unsigned long flags;
1050 
1051 	if (devinfo->shutdown)
1052 		return 0;
1053 
1054 	/* Block new requests */
1055 	spin_lock_irqsave(shost->host_lock, flags);
1056 	scsi_block_requests(shost);
1057 	spin_unlock_irqrestore(shost->host_lock, flags);
1058 
1059 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1060 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1061 		scsi_unblock_requests(shost);
1062 		return 1;
1063 	}
1064 
1065 	uas_free_streams(devinfo);
1066 
1067 	return 0;
1068 }
1069 
1070 static int uas_post_reset(struct usb_interface *intf)
1071 {
1072 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1073 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1074 	unsigned long flags;
1075 	int err;
1076 
1077 	if (devinfo->shutdown)
1078 		return 0;
1079 
1080 	err = uas_configure_endpoints(devinfo);
1081 	if (err) {
1082 		shost_printk(KERN_ERR, shost,
1083 			     "%s: alloc streams error %d after reset",
1084 			     __func__, err);
1085 		return 1;
1086 	}
1087 
1088 	spin_lock_irqsave(shost->host_lock, flags);
1089 	scsi_report_bus_reset(shost, 0);
1090 	spin_unlock_irqrestore(shost->host_lock, flags);
1091 
1092 	scsi_unblock_requests(shost);
1093 
1094 	return 0;
1095 }
1096 
1097 static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1098 {
1099 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1100 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1101 
1102 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1103 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1104 		return -ETIME;
1105 	}
1106 
1107 	return 0;
1108 }
1109 
1110 static int uas_resume(struct usb_interface *intf)
1111 {
1112 	return 0;
1113 }
1114 
1115 static int uas_reset_resume(struct usb_interface *intf)
1116 {
1117 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1118 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1119 	unsigned long flags;
1120 	int err;
1121 
1122 	err = uas_configure_endpoints(devinfo);
1123 	if (err) {
1124 		shost_printk(KERN_ERR, shost,
1125 			     "%s: alloc streams error %d after reset",
1126 			     __func__, err);
1127 		return -EIO;
1128 	}
1129 
1130 	spin_lock_irqsave(shost->host_lock, flags);
1131 	scsi_report_bus_reset(shost, 0);
1132 	spin_unlock_irqrestore(shost->host_lock, flags);
1133 
1134 	return 0;
1135 }
1136 
1137 static void uas_disconnect(struct usb_interface *intf)
1138 {
1139 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1140 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1141 	unsigned long flags;
1142 
1143 	spin_lock_irqsave(&devinfo->lock, flags);
1144 	devinfo->resetting = 1;
1145 	spin_unlock_irqrestore(&devinfo->lock, flags);
1146 
1147 	cancel_work_sync(&devinfo->work);
1148 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1149 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
1150 	usb_kill_anchored_urbs(&devinfo->data_urbs);
1151 	uas_zap_pending(devinfo, DID_NO_CONNECT);
1152 
1153 	scsi_remove_host(shost);
1154 	uas_free_streams(devinfo);
1155 	scsi_host_put(shost);
1156 }
1157 
1158 /*
1159  * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1160  * hang on reboot when the device is still in uas mode. Note the reset is
1161  * necessary as some devices won't revert to usb-storage mode without it.
1162  */
1163 static void uas_shutdown(struct device *dev)
1164 {
1165 	struct usb_interface *intf = to_usb_interface(dev);
1166 	struct usb_device *udev = interface_to_usbdev(intf);
1167 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1168 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1169 
1170 	if (system_state != SYSTEM_RESTART)
1171 		return;
1172 
1173 	devinfo->shutdown = 1;
1174 	uas_free_streams(devinfo);
1175 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1176 	usb_reset_device(udev);
1177 }
1178 
1179 static struct usb_driver uas_driver = {
1180 	.name = "uas",
1181 	.probe = uas_probe,
1182 	.disconnect = uas_disconnect,
1183 	.pre_reset = uas_pre_reset,
1184 	.post_reset = uas_post_reset,
1185 	.suspend = uas_suspend,
1186 	.resume = uas_resume,
1187 	.reset_resume = uas_reset_resume,
1188 	.drvwrap.driver.shutdown = uas_shutdown,
1189 	.id_table = uas_usb_ids,
1190 };
1191 
1192 module_usb_driver(uas_driver);
1193 
1194 MODULE_LICENSE("GPL");
1195 MODULE_AUTHOR(
1196 	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");
1197