xref: /linux/drivers/usb/storage/uas.c (revision f5e9d31e79c1ce8ba948ecac74d75e9c8d2f0c87)
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_devinfo.h>
25 #include <scsi/scsi_cmnd.h>
26 #include <scsi/scsi_device.h>
27 #include <scsi/scsi_host.h>
28 #include <scsi/scsi_tcq.h>
29 
30 #include "uas-detect.h"
31 #include "scsiglue.h"
32 
33 #define MAX_CMNDS 256
34 
35 struct uas_dev_info {
36 	struct usb_interface *intf;
37 	struct usb_device *udev;
38 	struct usb_anchor cmd_urbs;
39 	struct usb_anchor sense_urbs;
40 	struct usb_anchor data_urbs;
41 	u64 flags;
42 	int qdepth, resetting;
43 	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
44 	unsigned use_streams:1;
45 	unsigned shutdown:1;
46 	struct scsi_cmnd *cmnd[MAX_CMNDS];
47 	spinlock_t lock;
48 	struct work_struct work;
49 	struct work_struct scan_work;      /* for async scanning */
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 /*
86  * This driver needs its own workqueue, as we need to control memory allocation.
87  *
88  * In the course of error handling and power management uas_wait_for_pending_cmnds()
89  * needs to flush pending work items. In these contexts we cannot allocate memory
90  * by doing block IO as we would deadlock. For the same reason we cannot wait
91  * for anything allocating memory not heeding these constraints.
92  *
93  * So we have to control all work items that can be on the workqueue we flush.
94  * Hence we cannot share a queue and need our own.
95  */
96 static struct workqueue_struct *workqueue;
97 
uas_do_work(struct work_struct * work)98 static void uas_do_work(struct work_struct *work)
99 {
100 	struct uas_dev_info *devinfo =
101 		container_of(work, struct uas_dev_info, work);
102 	struct uas_cmd_info *cmdinfo;
103 	struct scsi_cmnd *cmnd;
104 	unsigned long flags;
105 	int i, err;
106 
107 	spin_lock_irqsave(&devinfo->lock, flags);
108 
109 	if (devinfo->resetting)
110 		goto out;
111 
112 	for (i = 0; i < devinfo->qdepth; i++) {
113 		if (!devinfo->cmnd[i])
114 			continue;
115 
116 		cmnd = devinfo->cmnd[i];
117 		cmdinfo = scsi_cmd_priv(cmnd);
118 
119 		if (!(cmdinfo->state & IS_IN_WORK_LIST))
120 			continue;
121 
122 		err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
123 		if (!err)
124 			cmdinfo->state &= ~IS_IN_WORK_LIST;
125 		else
126 			queue_work(workqueue, &devinfo->work);
127 	}
128 out:
129 	spin_unlock_irqrestore(&devinfo->lock, flags);
130 }
131 
uas_scan_work(struct work_struct * work)132 static void uas_scan_work(struct work_struct *work)
133 {
134 	struct uas_dev_info *devinfo =
135 		container_of(work, struct uas_dev_info, scan_work);
136 	struct Scsi_Host *shost = usb_get_intfdata(devinfo->intf);
137 
138 	dev_dbg(&devinfo->intf->dev, "starting scan\n");
139 	scsi_scan_host(shost);
140 	dev_dbg(&devinfo->intf->dev, "scan complete\n");
141 }
142 
uas_add_work(struct scsi_cmnd * cmnd)143 static void uas_add_work(struct scsi_cmnd *cmnd)
144 {
145 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
146 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
147 
148 	lockdep_assert_held(&devinfo->lock);
149 	cmdinfo->state |= IS_IN_WORK_LIST;
150 	queue_work(workqueue, &devinfo->work);
151 }
152 
uas_zap_pending(struct uas_dev_info * devinfo,int result)153 static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
154 {
155 	struct uas_cmd_info *cmdinfo;
156 	struct scsi_cmnd *cmnd;
157 	unsigned long flags;
158 	int i, err;
159 
160 	spin_lock_irqsave(&devinfo->lock, flags);
161 	for (i = 0; i < devinfo->qdepth; i++) {
162 		if (!devinfo->cmnd[i])
163 			continue;
164 
165 		cmnd = devinfo->cmnd[i];
166 		cmdinfo = scsi_cmd_priv(cmnd);
167 		uas_log_cmd_state(cmnd, __func__, 0);
168 		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
169 		cmdinfo->state &= ~COMMAND_INFLIGHT;
170 		cmnd->result = result << 16;
171 		err = uas_try_complete(cmnd, __func__);
172 		WARN_ON(err != 0);
173 	}
174 	spin_unlock_irqrestore(&devinfo->lock, flags);
175 }
176 
uas_sense(struct urb * urb,struct scsi_cmnd * cmnd)177 static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
178 {
179 	struct sense_iu *sense_iu = urb->transfer_buffer;
180 	struct scsi_device *sdev = cmnd->device;
181 
182 	if (urb->actual_length > 16) {
183 		unsigned len = be16_to_cpup(&sense_iu->len);
184 		if (len + 16 != urb->actual_length) {
185 			int newlen = min(len + 16, urb->actual_length) - 16;
186 			if (newlen < 0)
187 				newlen = 0;
188 			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
189 				"disagrees with IU sense data length %d, "
190 				"using %d bytes of sense data\n", __func__,
191 					urb->actual_length, len, newlen);
192 			len = newlen;
193 		}
194 		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
195 	}
196 
197 	cmnd->result = sense_iu->status;
198 }
199 
uas_log_cmd_state(struct scsi_cmnd * cmnd,const char * prefix,int status)200 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
201 			      int status)
202 {
203 	struct uas_cmd_info *ci = scsi_cmd_priv(cmnd);
204 
205 	if (status == -ENODEV) /* too late */
206 		return;
207 
208 	scmd_printk(KERN_INFO, cmnd,
209 		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
210 		    prefix, status, ci->uas_tag,
211 		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
212 		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
213 		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
214 		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
215 		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
216 		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
217 		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
218 		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
219 		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
220 		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
221 		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
222 		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
223 	scsi_print_command(cmnd);
224 }
225 
uas_free_unsubmitted_urbs(struct scsi_cmnd * cmnd)226 static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
227 {
228 	struct uas_cmd_info *cmdinfo;
229 
230 	if (!cmnd)
231 		return;
232 
233 	cmdinfo = scsi_cmd_priv(cmnd);
234 
235 	if (cmdinfo->state & SUBMIT_CMD_URB)
236 		usb_free_urb(cmdinfo->cmd_urb);
237 
238 	/* data urbs may have never gotten their submit flag set */
239 	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
240 		usb_free_urb(cmdinfo->data_in_urb);
241 	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
242 		usb_free_urb(cmdinfo->data_out_urb);
243 }
244 
uas_try_complete(struct scsi_cmnd * cmnd,const char * caller)245 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
246 {
247 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
248 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
249 
250 	lockdep_assert_held(&devinfo->lock);
251 	if (cmdinfo->state & (COMMAND_INFLIGHT |
252 			      DATA_IN_URB_INFLIGHT |
253 			      DATA_OUT_URB_INFLIGHT |
254 			      COMMAND_ABORTED))
255 		return -EBUSY;
256 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
257 	uas_free_unsubmitted_urbs(cmnd);
258 	scsi_done(cmnd);
259 	return 0;
260 }
261 
uas_xfer_data(struct urb * urb,struct scsi_cmnd * cmnd,unsigned direction)262 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
263 			  unsigned direction)
264 {
265 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
266 	int err;
267 
268 	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
269 	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
270 	if (err) {
271 		uas_add_work(cmnd);
272 	}
273 }
274 
uas_evaluate_response_iu(struct response_iu * riu,struct scsi_cmnd * cmnd)275 static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
276 {
277 	u8 response_code = riu->response_code;
278 
279 	switch (response_code) {
280 	case RC_INCORRECT_LUN:
281 		set_host_byte(cmnd, DID_BAD_TARGET);
282 		break;
283 	case RC_TMF_SUCCEEDED:
284 		set_host_byte(cmnd, DID_OK);
285 		break;
286 	case RC_TMF_NOT_SUPPORTED:
287 		set_host_byte(cmnd, DID_BAD_TARGET);
288 		break;
289 	default:
290 		uas_log_cmd_state(cmnd, "response iu", response_code);
291 		set_host_byte(cmnd, DID_ERROR);
292 		break;
293 	}
294 
295 	return response_code == RC_TMF_SUCCEEDED;
296 }
297 
uas_stat_cmplt(struct urb * urb)298 static void uas_stat_cmplt(struct urb *urb)
299 {
300 	struct iu *iu = urb->transfer_buffer;
301 	struct Scsi_Host *shost = urb->context;
302 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
303 	struct urb *data_in_urb = NULL;
304 	struct urb *data_out_urb = NULL;
305 	struct scsi_cmnd *cmnd;
306 	struct uas_cmd_info *cmdinfo;
307 	unsigned long flags;
308 	unsigned int idx;
309 	int status = urb->status;
310 	bool success;
311 
312 	if (status) {
313 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
314 			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
315 		goto bail;
316 	}
317 
318 	idx = be16_to_cpup(&iu->tag) - 1;
319 
320 	spin_lock_irqsave(&devinfo->lock, flags);
321 
322 	if (devinfo->resetting)
323 		goto out;
324 	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
325 		dev_err(&urb->dev->dev,
326 			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
327 		goto out;
328 	}
329 
330 	cmnd = devinfo->cmnd[idx];
331 	cmdinfo = scsi_cmd_priv(cmnd);
332 
333 	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
334 		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
335 		goto out;
336 	}
337 
338 	switch (iu->iu_id) {
339 	case IU_ID_STATUS:
340 		uas_sense(urb, cmnd);
341 		if (cmnd->result != 0) {
342 			/* cancel data transfers on error */
343 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
344 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
345 		}
346 		cmdinfo->state &= ~COMMAND_INFLIGHT;
347 		uas_try_complete(cmnd, __func__);
348 		break;
349 	case IU_ID_READ_READY:
350 		if (!cmdinfo->data_in_urb ||
351 				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
352 			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
353 			break;
354 		}
355 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
356 		break;
357 	case IU_ID_WRITE_READY:
358 		if (!cmdinfo->data_out_urb ||
359 				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
360 			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
361 			break;
362 		}
363 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
364 		break;
365 	case IU_ID_RESPONSE:
366 		cmdinfo->state &= ~COMMAND_INFLIGHT;
367 		success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
368 		if (!success) {
369 			/* Error, cancel data transfers */
370 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
371 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
372 		}
373 		uas_try_complete(cmnd, __func__);
374 		break;
375 	default:
376 		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
377 	}
378 	spin_unlock_irqrestore(&devinfo->lock, flags);
379 	usb_free_urb(urb);
380 
381 	/* Unlinking of data urbs must be done without holding the lock */
382 	if (data_in_urb) {
383 		usb_unlink_urb(data_in_urb);
384 		usb_put_urb(data_in_urb);
385 	}
386 	if (data_out_urb) {
387 		usb_unlink_urb(data_out_urb);
388 		usb_put_urb(data_out_urb);
389 	}
390 	return;
391 
392 out:
393 	spin_unlock_irqrestore(&devinfo->lock, flags);
394 bail:
395 	usb_free_urb(urb);
396 }
397 
uas_data_cmplt(struct urb * urb)398 static void uas_data_cmplt(struct urb *urb)
399 {
400 	struct scsi_cmnd *cmnd = urb->context;
401 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
402 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
403 	struct scsi_data_buffer *sdb = &cmnd->sdb;
404 	unsigned long flags;
405 	int status = urb->status;
406 
407 	spin_lock_irqsave(&devinfo->lock, flags);
408 
409 	if (cmdinfo->data_in_urb == urb) {
410 		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
411 		cmdinfo->data_in_urb = NULL;
412 	} else if (cmdinfo->data_out_urb == urb) {
413 		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
414 		cmdinfo->data_out_urb = NULL;
415 	}
416 
417 	if (devinfo->resetting)
418 		goto out;
419 
420 	/* Data urbs should not complete before the cmd urb is submitted */
421 	if (cmdinfo->state & SUBMIT_CMD_URB) {
422 		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
423 		goto out;
424 	}
425 
426 	if (status) {
427 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
428 			uas_log_cmd_state(cmnd, "data cmplt err", status);
429 		/* error: no data transfered */
430 		scsi_set_resid(cmnd, sdb->length);
431 		set_host_byte(cmnd, DID_ERROR);
432 	} else {
433 		scsi_set_resid(cmnd, sdb->length - urb->actual_length);
434 	}
435 	uas_try_complete(cmnd, __func__);
436 out:
437 	spin_unlock_irqrestore(&devinfo->lock, flags);
438 	usb_free_urb(urb);
439 }
440 
uas_cmd_cmplt(struct urb * urb)441 static void uas_cmd_cmplt(struct urb *urb)
442 {
443 	if (urb->status)
444 		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
445 
446 	usb_free_urb(urb);
447 }
448 
uas_alloc_data_urb(struct uas_dev_info * devinfo,gfp_t gfp,struct scsi_cmnd * cmnd,enum dma_data_direction dir)449 static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
450 				      struct scsi_cmnd *cmnd,
451 				      enum dma_data_direction dir)
452 {
453 	struct usb_device *udev = devinfo->udev;
454 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
455 	struct urb *urb = usb_alloc_urb(0, gfp);
456 	struct scsi_data_buffer *sdb = &cmnd->sdb;
457 	unsigned int pipe = (dir == DMA_FROM_DEVICE)
458 		? devinfo->data_in_pipe : devinfo->data_out_pipe;
459 
460 	if (!urb)
461 		goto out;
462 	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
463 			  uas_data_cmplt, cmnd);
464 	if (devinfo->use_streams)
465 		urb->stream_id = cmdinfo->uas_tag;
466 	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
467 	urb->sg = sdb->table.sgl;
468  out:
469 	return urb;
470 }
471 
uas_alloc_sense_urb(struct uas_dev_info * devinfo,gfp_t gfp,struct scsi_cmnd * cmnd)472 static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
473 				       struct scsi_cmnd *cmnd)
474 {
475 	struct usb_device *udev = devinfo->udev;
476 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
477 	struct urb *urb = usb_alloc_urb(0, gfp);
478 	struct sense_iu *iu;
479 
480 	if (!urb)
481 		goto out;
482 
483 	iu = kzalloc(sizeof(*iu), gfp);
484 	if (!iu)
485 		goto free;
486 
487 	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
488 			  uas_stat_cmplt, cmnd->device->host);
489 	if (devinfo->use_streams)
490 		urb->stream_id = cmdinfo->uas_tag;
491 	urb->transfer_flags |= URB_FREE_BUFFER;
492  out:
493 	return urb;
494  free:
495 	usb_free_urb(urb);
496 	return NULL;
497 }
498 
uas_alloc_cmd_urb(struct uas_dev_info * devinfo,gfp_t gfp,struct scsi_cmnd * cmnd)499 static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
500 					struct scsi_cmnd *cmnd)
501 {
502 	struct usb_device *udev = devinfo->udev;
503 	struct scsi_device *sdev = cmnd->device;
504 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
505 	struct urb *urb = usb_alloc_urb(0, gfp);
506 	struct command_iu *iu;
507 	int len;
508 
509 	if (!urb)
510 		goto out;
511 
512 	len = cmnd->cmd_len - 16;
513 	if (len < 0)
514 		len = 0;
515 	len = ALIGN(len, 4);
516 	iu = kzalloc(sizeof(*iu) + len, gfp);
517 	if (!iu)
518 		goto free;
519 
520 	iu->iu_id = IU_ID_COMMAND;
521 	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
522 	iu->prio_attr = UAS_SIMPLE_TAG;
523 	iu->len = len;
524 	int_to_scsilun(sdev->lun, &iu->lun);
525 	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
526 
527 	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
528 							uas_cmd_cmplt, NULL);
529 	urb->transfer_flags |= URB_FREE_BUFFER;
530  out:
531 	return urb;
532  free:
533 	usb_free_urb(urb);
534 	return NULL;
535 }
536 
537 /*
538  * Why should I request the Status IU before sending the Command IU?  Spec
539  * says to, but also says the device may receive them in any order.  Seems
540  * daft to me.
541  */
542 
uas_submit_sense_urb(struct scsi_cmnd * cmnd,gfp_t gfp)543 static int uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
544 {
545 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
546 	struct urb *urb;
547 	int err;
548 
549 	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
550 	if (!urb)
551 		return -ENOMEM;
552 	usb_anchor_urb(urb, &devinfo->sense_urbs);
553 	err = usb_submit_urb(urb, gfp);
554 	if (err) {
555 		usb_unanchor_urb(urb);
556 		uas_log_cmd_state(cmnd, "sense submit err", err);
557 		usb_free_urb(urb);
558 	}
559 	return err;
560 }
561 
uas_submit_urbs(struct scsi_cmnd * cmnd,struct uas_dev_info * devinfo)562 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
563 			   struct uas_dev_info *devinfo)
564 {
565 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
566 	int err;
567 
568 	lockdep_assert_held(&devinfo->lock);
569 	if (cmdinfo->state & SUBMIT_STATUS_URB) {
570 		err = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
571 		if (err)
572 			return err;
573 		cmdinfo->state &= ~SUBMIT_STATUS_URB;
574 	}
575 
576 	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
577 		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
578 							cmnd, DMA_FROM_DEVICE);
579 		if (!cmdinfo->data_in_urb)
580 			return -ENOMEM;
581 		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
582 	}
583 
584 	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
585 		usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
586 		err = usb_submit_urb(cmdinfo->data_in_urb, GFP_ATOMIC);
587 		if (err) {
588 			usb_unanchor_urb(cmdinfo->data_in_urb);
589 			uas_log_cmd_state(cmnd, "data in submit err", err);
590 			return err;
591 		}
592 		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
593 		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
594 	}
595 
596 	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
597 		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
598 							cmnd, DMA_TO_DEVICE);
599 		if (!cmdinfo->data_out_urb)
600 			return -ENOMEM;
601 		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
602 	}
603 
604 	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
605 		usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
606 		err = usb_submit_urb(cmdinfo->data_out_urb, GFP_ATOMIC);
607 		if (err) {
608 			usb_unanchor_urb(cmdinfo->data_out_urb);
609 			uas_log_cmd_state(cmnd, "data out submit err", err);
610 			return err;
611 		}
612 		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
613 		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
614 	}
615 
616 	if (cmdinfo->state & ALLOC_CMD_URB) {
617 		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
618 		if (!cmdinfo->cmd_urb)
619 			return -ENOMEM;
620 		cmdinfo->state &= ~ALLOC_CMD_URB;
621 	}
622 
623 	if (cmdinfo->state & SUBMIT_CMD_URB) {
624 		usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
625 		err = usb_submit_urb(cmdinfo->cmd_urb, GFP_ATOMIC);
626 		if (err) {
627 			usb_unanchor_urb(cmdinfo->cmd_urb);
628 			uas_log_cmd_state(cmnd, "cmd submit err", err);
629 			return err;
630 		}
631 		cmdinfo->cmd_urb = NULL;
632 		cmdinfo->state &= ~SUBMIT_CMD_URB;
633 		cmdinfo->state |= COMMAND_INFLIGHT;
634 	}
635 
636 	return 0;
637 }
638 
uas_queuecommand_lck(struct scsi_cmnd * cmnd)639 static int uas_queuecommand_lck(struct scsi_cmnd *cmnd)
640 {
641 	struct scsi_device *sdev = cmnd->device;
642 	struct uas_dev_info *devinfo = sdev->hostdata;
643 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
644 	unsigned long flags;
645 	int idx, err;
646 
647 	/* Re-check scsi_block_requests now that we've the host-lock */
648 	if (cmnd->device->host->host_self_blocked)
649 		return SCSI_MLQUEUE_DEVICE_BUSY;
650 
651 	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
652 			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
653 		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
654 		       sizeof(usb_stor_sense_invalidCDB));
655 		cmnd->result = SAM_STAT_CHECK_CONDITION;
656 		scsi_done(cmnd);
657 		return 0;
658 	}
659 
660 	spin_lock_irqsave(&devinfo->lock, flags);
661 
662 	if (devinfo->resetting) {
663 		set_host_byte(cmnd, DID_ERROR);
664 		scsi_done(cmnd);
665 		goto zombie;
666 	}
667 
668 	/* Find a free uas-tag */
669 	for (idx = 0; idx < devinfo->qdepth; idx++) {
670 		if (!devinfo->cmnd[idx])
671 			break;
672 	}
673 	if (idx == devinfo->qdepth) {
674 		spin_unlock_irqrestore(&devinfo->lock, flags);
675 		return SCSI_MLQUEUE_DEVICE_BUSY;
676 	}
677 
678 	memset(cmdinfo, 0, sizeof(*cmdinfo));
679 	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
680 	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
681 
682 	switch (cmnd->sc_data_direction) {
683 	case DMA_FROM_DEVICE:
684 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
685 		break;
686 	case DMA_BIDIRECTIONAL:
687 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
688 		fallthrough;
689 	case DMA_TO_DEVICE:
690 		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
691 		break;
692 	case DMA_NONE:
693 		break;
694 	}
695 
696 	if (!devinfo->use_streams)
697 		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
698 
699 	err = uas_submit_urbs(cmnd, devinfo);
700 	/*
701 	 * in case of fatal errors the SCSI layer is peculiar
702 	 * a command that has finished is a success for the purpose
703 	 * of queueing, no matter how fatal the error
704 	 */
705 	if (err == -ENODEV) {
706 		if (cmdinfo->state & (COMMAND_INFLIGHT | DATA_IN_URB_INFLIGHT |
707 				DATA_OUT_URB_INFLIGHT))
708 			goto out;
709 
710 		set_host_byte(cmnd, DID_NO_CONNECT);
711 		scsi_done(cmnd);
712 		goto zombie;
713 	}
714 	if (err) {
715 		/* If we did nothing, give up now */
716 		if (cmdinfo->state & SUBMIT_STATUS_URB) {
717 			spin_unlock_irqrestore(&devinfo->lock, flags);
718 			return SCSI_MLQUEUE_DEVICE_BUSY;
719 		}
720 		uas_add_work(cmnd);
721 	}
722 
723 out:
724 	devinfo->cmnd[idx] = cmnd;
725 zombie:
726 	spin_unlock_irqrestore(&devinfo->lock, flags);
727 	return 0;
728 }
729 
DEF_SCSI_QCMD(uas_queuecommand)730 static DEF_SCSI_QCMD(uas_queuecommand)
731 
732 /*
733  * For now we do not support actually sending an abort to the device, so
734  * this eh always fails. Still we must define it to make sure that we've
735  * dropped all references to the cmnd in question once this function exits.
736  */
737 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
738 {
739 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
740 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
741 	struct urb *data_in_urb = NULL;
742 	struct urb *data_out_urb = NULL;
743 	unsigned long flags;
744 
745 	spin_lock_irqsave(&devinfo->lock, flags);
746 
747 	uas_log_cmd_state(cmnd, __func__, 0);
748 
749 	/* Ensure that try_complete does not call scsi_done */
750 	cmdinfo->state |= COMMAND_ABORTED;
751 
752 	/* Drop all refs to this cmnd, kill data urbs to break their ref */
753 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
754 	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
755 		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
756 	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
757 		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
758 
759 	uas_free_unsubmitted_urbs(cmnd);
760 
761 	spin_unlock_irqrestore(&devinfo->lock, flags);
762 
763 	if (data_in_urb) {
764 		usb_kill_urb(data_in_urb);
765 		usb_put_urb(data_in_urb);
766 	}
767 	if (data_out_urb) {
768 		usb_kill_urb(data_out_urb);
769 		usb_put_urb(data_out_urb);
770 	}
771 
772 	return FAILED;
773 }
774 
uas_eh_device_reset_handler(struct scsi_cmnd * cmnd)775 static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
776 {
777 	struct scsi_device *sdev = cmnd->device;
778 	struct uas_dev_info *devinfo = sdev->hostdata;
779 	struct usb_device *udev = devinfo->udev;
780 	unsigned long flags;
781 	int err;
782 
783 	err = usb_lock_device_for_reset(udev, devinfo->intf);
784 	if (err) {
785 		shost_printk(KERN_ERR, sdev->host,
786 			     "%s FAILED to get lock err %d\n", __func__, err);
787 		return FAILED;
788 	}
789 
790 	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
791 
792 	spin_lock_irqsave(&devinfo->lock, flags);
793 	devinfo->resetting = 1;
794 	spin_unlock_irqrestore(&devinfo->lock, flags);
795 
796 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
797 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
798 	usb_kill_anchored_urbs(&devinfo->data_urbs);
799 	uas_zap_pending(devinfo, DID_RESET);
800 
801 	err = usb_reset_device(udev);
802 
803 	spin_lock_irqsave(&devinfo->lock, flags);
804 	devinfo->resetting = 0;
805 	spin_unlock_irqrestore(&devinfo->lock, flags);
806 
807 	usb_unlock_device(udev);
808 
809 	if (err) {
810 		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
811 			     __func__, err);
812 		return FAILED;
813 	}
814 
815 	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
816 	return SUCCESS;
817 }
818 
uas_target_alloc(struct scsi_target * starget)819 static int uas_target_alloc(struct scsi_target *starget)
820 {
821 	struct uas_dev_info *devinfo = (struct uas_dev_info *)
822 			dev_to_shost(starget->dev.parent)->hostdata;
823 
824 	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
825 		starget->no_report_luns = 1;
826 
827 	return 0;
828 }
829 
uas_sdev_init(struct scsi_device * sdev)830 static int uas_sdev_init(struct scsi_device *sdev)
831 {
832 	struct uas_dev_info *devinfo =
833 		(struct uas_dev_info *)sdev->host->hostdata;
834 
835 	/*
836 	 * Some USB storage devices reset if the IO advice hints grouping mode
837 	 * page is queried. Hence skip that mode page.
838 	 */
839 	sdev->sdev_bflags |= BLIST_SKIP_IO_HINTS;
840 
841 	sdev->hostdata = devinfo;
842 	return 0;
843 }
844 
uas_sdev_configure(struct scsi_device * sdev,struct queue_limits * lim)845 static int uas_sdev_configure(struct scsi_device *sdev,
846 			      struct queue_limits *lim)
847 {
848 	struct uas_dev_info *devinfo = sdev->hostdata;
849 
850 	if (devinfo->flags & US_FL_MAX_SECTORS_64)
851 		lim->max_hw_sectors = 64;
852 	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
853 		lim->max_hw_sectors = 240;
854 
855 	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
856 		sdev->no_report_opcodes = 1;
857 
858 	/* A few buggy USB-ATA bridges don't understand FUA */
859 	if (devinfo->flags & US_FL_BROKEN_FUA)
860 		sdev->broken_fua = 1;
861 
862 	/* UAS also needs to support FL_ALWAYS_SYNC */
863 	if (devinfo->flags & US_FL_ALWAYS_SYNC) {
864 		sdev->skip_ms_page_3f = 1;
865 		sdev->skip_ms_page_8 = 1;
866 		sdev->wce_default_on = 1;
867 	}
868 
869 	/* Some disks cannot handle READ_CAPACITY_16 */
870 	if (devinfo->flags & US_FL_NO_READ_CAPACITY_16)
871 		sdev->no_read_capacity_16 = 1;
872 
873 	/* Some disks cannot handle WRITE_SAME */
874 	if (devinfo->flags & US_FL_NO_SAME)
875 		sdev->no_write_same = 1;
876 	/*
877 	 * Some disks return the total number of blocks in response
878 	 * to READ CAPACITY rather than the highest block number.
879 	 * If this device makes that mistake, tell the sd driver.
880 	 */
881 	if (devinfo->flags & US_FL_FIX_CAPACITY)
882 		sdev->fix_capacity = 1;
883 
884 	/*
885 	 * in some cases we have to guess
886 	 */
887 	if (devinfo->flags & US_FL_CAPACITY_HEURISTICS)
888 		sdev->guess_capacity = 1;
889 
890 	/*
891 	 * Some devices report generic values until the media has been
892 	 * accessed. Force a READ(10) prior to querying device
893 	 * characteristics.
894 	 */
895 	sdev->read_before_ms = 1;
896 
897 	/*
898 	 * Some devices don't like MODE SENSE with page=0x3f,
899 	 * which is the command used for checking if a device
900 	 * is write-protected.  Now that we tell the sd driver
901 	 * to do a 192-byte transfer with this command the
902 	 * majority of devices work fine, but a few still can't
903 	 * handle it.  The sd driver will simply assume those
904 	 * devices are write-enabled.
905 	 */
906 	if (devinfo->flags & US_FL_NO_WP_DETECT)
907 		sdev->skip_ms_page_3f = 1;
908 
909 	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
910 	return 0;
911 }
912 
913 static const struct scsi_host_template uas_host_template = {
914 	.module = THIS_MODULE,
915 	.name = "uas",
916 	.queuecommand = uas_queuecommand,
917 	.target_alloc = uas_target_alloc,
918 	.sdev_init = uas_sdev_init,
919 	.sdev_configure = uas_sdev_configure,
920 	.eh_abort_handler = uas_eh_abort_handler,
921 	.eh_device_reset_handler = uas_eh_device_reset_handler,
922 	.this_id = -1,
923 	.skip_settle_delay = 1,
924 	/*
925 	 * The protocol has no requirements on alignment in the strict sense.
926 	 * Controllers may or may not have alignment restrictions.
927 	 * As this is not exported, we use an extremely conservative guess.
928 	 */
929 	.dma_alignment = 511,
930 	.dma_boundary = PAGE_SIZE - 1,
931 	.cmd_size = sizeof(struct uas_cmd_info),
932 };
933 
934 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
935 		    vendorName, productName, useProtocol, useTransport, \
936 		    initFunction, flags) \
937 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
938 	.driver_info = (flags) }
939 
940 static const struct usb_device_id uas_usb_ids[] = {
941 #	include "unusual_uas.h"
942 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
943 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
944 	{ }
945 };
946 MODULE_DEVICE_TABLE(usb, uas_usb_ids);
947 
948 #undef UNUSUAL_DEV
949 
uas_switch_interface(struct usb_device * udev,struct usb_interface * intf)950 static int uas_switch_interface(struct usb_device *udev,
951 				struct usb_interface *intf)
952 {
953 	struct usb_host_interface *alt;
954 
955 	alt = uas_find_uas_alt_setting(intf);
956 	if (!alt)
957 		return -ENODEV;
958 
959 	return usb_set_interface(udev, alt->desc.bInterfaceNumber,
960 			alt->desc.bAlternateSetting);
961 }
962 
uas_configure_endpoints(struct uas_dev_info * devinfo)963 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
964 {
965 	struct usb_host_endpoint *eps[4] = { };
966 	struct usb_device *udev = devinfo->udev;
967 	int r;
968 
969 	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
970 	if (r)
971 		return r;
972 
973 	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
974 					    usb_endpoint_num(&eps[0]->desc));
975 	devinfo->status_pipe = usb_rcvbulkpipe(udev,
976 					    usb_endpoint_num(&eps[1]->desc));
977 	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
978 					    usb_endpoint_num(&eps[2]->desc));
979 	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
980 					    usb_endpoint_num(&eps[3]->desc));
981 
982 	if (udev->speed < USB_SPEED_SUPER) {
983 		devinfo->qdepth = 32;
984 		devinfo->use_streams = 0;
985 	} else {
986 		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
987 						    3, MAX_CMNDS, GFP_NOIO);
988 		if (devinfo->qdepth < 0)
989 			return devinfo->qdepth;
990 		devinfo->use_streams = 1;
991 	}
992 
993 	return 0;
994 }
995 
uas_free_streams(struct uas_dev_info * devinfo)996 static void uas_free_streams(struct uas_dev_info *devinfo)
997 {
998 	struct usb_device *udev = devinfo->udev;
999 	struct usb_host_endpoint *eps[3];
1000 
1001 	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
1002 	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
1003 	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
1004 	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
1005 }
1006 
uas_probe(struct usb_interface * intf,const struct usb_device_id * id)1007 static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
1008 {
1009 	int result = -ENOMEM;
1010 	struct Scsi_Host *shost = NULL;
1011 	struct uas_dev_info *devinfo;
1012 	struct usb_device *udev = interface_to_usbdev(intf);
1013 	u64 dev_flags;
1014 
1015 	if (!uas_use_uas_driver(intf, id, &dev_flags))
1016 		return -ENODEV;
1017 
1018 	if (uas_switch_interface(udev, intf))
1019 		return -ENODEV;
1020 
1021 	shost = scsi_host_alloc(&uas_host_template,
1022 				sizeof(struct uas_dev_info));
1023 	if (!shost)
1024 		goto set_alt0;
1025 
1026 	shost->max_cmd_len = 16 + 252;
1027 	shost->max_id = 1;
1028 	shost->max_lun = 256;
1029 	shost->max_channel = 0;
1030 	shost->sg_tablesize = udev->bus->sg_tablesize;
1031 
1032 	devinfo = (struct uas_dev_info *)shost->hostdata;
1033 	devinfo->intf = intf;
1034 	devinfo->udev = udev;
1035 	devinfo->resetting = 0;
1036 	devinfo->shutdown = 0;
1037 	devinfo->flags = dev_flags;
1038 	init_usb_anchor(&devinfo->cmd_urbs);
1039 	init_usb_anchor(&devinfo->sense_urbs);
1040 	init_usb_anchor(&devinfo->data_urbs);
1041 	spin_lock_init(&devinfo->lock);
1042 	INIT_WORK(&devinfo->work, uas_do_work);
1043 	INIT_WORK(&devinfo->scan_work, uas_scan_work);
1044 
1045 	result = uas_configure_endpoints(devinfo);
1046 	if (result)
1047 		goto set_alt0;
1048 
1049 	/*
1050 	 * 1 tag is reserved for untagged commands +
1051 	 * 1 tag to avoid off by one errors in some bridge firmwares
1052 	 */
1053 	shost->can_queue = devinfo->qdepth - 2;
1054 
1055 	usb_set_intfdata(intf, shost);
1056 	result = scsi_add_host(shost, &intf->dev);
1057 	if (result)
1058 		goto free_streams;
1059 
1060 	/* Submit the delayed_work for SCSI-device scanning */
1061 	schedule_work(&devinfo->scan_work);
1062 
1063 	return result;
1064 
1065 free_streams:
1066 	uas_free_streams(devinfo);
1067 	usb_set_intfdata(intf, NULL);
1068 set_alt0:
1069 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1070 	if (shost)
1071 		scsi_host_put(shost);
1072 	return result;
1073 }
1074 
uas_cmnd_list_empty(struct uas_dev_info * devinfo)1075 static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
1076 {
1077 	unsigned long flags;
1078 	int i, r = 1;
1079 
1080 	spin_lock_irqsave(&devinfo->lock, flags);
1081 
1082 	for (i = 0; i < devinfo->qdepth; i++) {
1083 		if (devinfo->cmnd[i]) {
1084 			r = 0; /* Not empty */
1085 			break;
1086 		}
1087 	}
1088 
1089 	spin_unlock_irqrestore(&devinfo->lock, flags);
1090 
1091 	return r;
1092 }
1093 
1094 /*
1095  * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
1096  * get empty while there still is more work to do due to sense-urbs completing
1097  * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
1098  */
uas_wait_for_pending_cmnds(struct uas_dev_info * devinfo)1099 static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
1100 {
1101 	unsigned long start_time;
1102 	int r;
1103 
1104 	start_time = jiffies;
1105 	do {
1106 		flush_work(&devinfo->work);
1107 
1108 		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1109 		if (r == 0)
1110 			return -ETIME;
1111 
1112 		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1113 		if (r == 0)
1114 			return -ETIME;
1115 
1116 		if (time_after(jiffies, start_time + 5 * HZ))
1117 			return -ETIME;
1118 	} while (!uas_cmnd_list_empty(devinfo));
1119 
1120 	return 0;
1121 }
1122 
uas_pre_reset(struct usb_interface * intf)1123 static int uas_pre_reset(struct usb_interface *intf)
1124 {
1125 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1126 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1127 	unsigned long flags;
1128 
1129 	if (devinfo->shutdown)
1130 		return 0;
1131 
1132 	/* Block new requests */
1133 	spin_lock_irqsave(shost->host_lock, flags);
1134 	scsi_block_requests(shost);
1135 	spin_unlock_irqrestore(shost->host_lock, flags);
1136 
1137 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1138 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1139 		scsi_unblock_requests(shost);
1140 		return 1;
1141 	}
1142 
1143 	uas_free_streams(devinfo);
1144 
1145 	return 0;
1146 }
1147 
uas_post_reset(struct usb_interface * intf)1148 static int uas_post_reset(struct usb_interface *intf)
1149 {
1150 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1151 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1152 	unsigned long flags;
1153 	int err;
1154 
1155 	if (devinfo->shutdown)
1156 		return 0;
1157 
1158 	err = uas_configure_endpoints(devinfo);
1159 	if (err && err != -ENODEV)
1160 		shost_printk(KERN_ERR, shost,
1161 			     "%s: alloc streams error %d after reset",
1162 			     __func__, err);
1163 
1164 	/* we must unblock the host in every case lest we deadlock */
1165 	spin_lock_irqsave(shost->host_lock, flags);
1166 	scsi_report_bus_reset(shost, 0);
1167 	spin_unlock_irqrestore(shost->host_lock, flags);
1168 
1169 	scsi_unblock_requests(shost);
1170 
1171 	return err ? 1 : 0;
1172 }
1173 
uas_suspend(struct usb_interface * intf,pm_message_t message)1174 static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1175 {
1176 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1177 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1178 
1179 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1180 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1181 		return -ETIME;
1182 	}
1183 
1184 	return 0;
1185 }
1186 
uas_resume(struct usb_interface * intf)1187 static int uas_resume(struct usb_interface *intf)
1188 {
1189 	return 0;
1190 }
1191 
uas_reset_resume(struct usb_interface * intf)1192 static int uas_reset_resume(struct usb_interface *intf)
1193 {
1194 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1195 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1196 	unsigned long flags;
1197 	int err;
1198 
1199 	err = uas_configure_endpoints(devinfo);
1200 	if (err) {
1201 		shost_printk(KERN_ERR, shost,
1202 			     "%s: alloc streams error %d after reset",
1203 			     __func__, err);
1204 		return -EIO;
1205 	}
1206 
1207 	spin_lock_irqsave(shost->host_lock, flags);
1208 	scsi_report_bus_reset(shost, 0);
1209 	spin_unlock_irqrestore(shost->host_lock, flags);
1210 
1211 	return 0;
1212 }
1213 
uas_disconnect(struct usb_interface * intf)1214 static void uas_disconnect(struct usb_interface *intf)
1215 {
1216 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1217 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1218 	unsigned long flags;
1219 
1220 	spin_lock_irqsave(&devinfo->lock, flags);
1221 	devinfo->resetting = 1;
1222 	spin_unlock_irqrestore(&devinfo->lock, flags);
1223 
1224 	cancel_work_sync(&devinfo->work);
1225 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1226 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
1227 	usb_kill_anchored_urbs(&devinfo->data_urbs);
1228 	uas_zap_pending(devinfo, DID_NO_CONNECT);
1229 
1230 	/*
1231 	 * Prevent SCSI scanning (if it hasn't started yet)
1232 	 * or wait for the SCSI-scanning routine to stop.
1233 	 */
1234 	cancel_work_sync(&devinfo->scan_work);
1235 
1236 	scsi_remove_host(shost);
1237 	uas_free_streams(devinfo);
1238 	scsi_host_put(shost);
1239 }
1240 
1241 /*
1242  * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1243  * hang on reboot when the device is still in uas mode. Note the reset is
1244  * necessary as some devices won't revert to usb-storage mode without it.
1245  */
uas_shutdown(struct usb_interface * intf)1246 static void uas_shutdown(struct usb_interface *intf)
1247 {
1248 	struct usb_device *udev = interface_to_usbdev(intf);
1249 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1250 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1251 
1252 	if (system_state != SYSTEM_RESTART)
1253 		return;
1254 
1255 	devinfo->shutdown = 1;
1256 	uas_free_streams(devinfo);
1257 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1258 	usb_reset_device(udev);
1259 }
1260 
1261 static struct usb_driver uas_driver = {
1262 	.name = "uas",
1263 	.probe = uas_probe,
1264 	.disconnect = uas_disconnect,
1265 	.pre_reset = uas_pre_reset,
1266 	.post_reset = uas_post_reset,
1267 	.suspend = uas_suspend,
1268 	.resume = uas_resume,
1269 	.reset_resume = uas_reset_resume,
1270 	.shutdown = uas_shutdown,
1271 	.id_table = uas_usb_ids,
1272 };
1273 
uas_init(void)1274 static int __init uas_init(void)
1275 {
1276 	int rv;
1277 
1278 	workqueue = alloc_workqueue("uas", WQ_MEM_RECLAIM | WQ_PERCPU, 0);
1279 	if (!workqueue)
1280 		return -ENOMEM;
1281 
1282 	rv = usb_register(&uas_driver);
1283 	if (rv) {
1284 		destroy_workqueue(workqueue);
1285 		return -ENOMEM;
1286 	}
1287 
1288 	return 0;
1289 }
1290 
uas_exit(void)1291 static void __exit uas_exit(void)
1292 {
1293 	usb_deregister(&uas_driver);
1294 	destroy_workqueue(workqueue);
1295 }
1296 
1297 module_init(uas_init);
1298 module_exit(uas_exit);
1299 
1300 MODULE_DESCRIPTION("USB Attached SCSI driver");
1301 MODULE_LICENSE("GPL");
1302 MODULE_IMPORT_NS("USB_STORAGE");
1303 MODULE_AUTHOR(
1304 	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");
1305