xref: /openbmc/linux/drivers/usb/storage/uas.c (revision ce748df0)
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 	struct work_struct scan_work;      /* for async scanning */
49 };
50 
51 enum {
52 	SUBMIT_STATUS_URB	= BIT(1),
53 	ALLOC_DATA_IN_URB	= BIT(2),
54 	SUBMIT_DATA_IN_URB	= BIT(3),
55 	ALLOC_DATA_OUT_URB	= BIT(4),
56 	SUBMIT_DATA_OUT_URB	= BIT(5),
57 	ALLOC_CMD_URB		= BIT(6),
58 	SUBMIT_CMD_URB		= BIT(7),
59 	COMMAND_INFLIGHT        = BIT(8),
60 	DATA_IN_URB_INFLIGHT    = BIT(9),
61 	DATA_OUT_URB_INFLIGHT   = BIT(10),
62 	COMMAND_ABORTED         = BIT(11),
63 	IS_IN_WORK_LIST         = BIT(12),
64 };
65 
66 /* Overrides scsi_pointer */
67 struct uas_cmd_info {
68 	unsigned int state;
69 	unsigned int uas_tag;
70 	struct urb *cmd_urb;
71 	struct urb *data_in_urb;
72 	struct urb *data_out_urb;
73 };
74 
75 /* I hate forward declarations, but I actually have a loop */
76 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
77 				struct uas_dev_info *devinfo);
78 static void uas_do_work(struct work_struct *work);
79 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller);
80 static void uas_free_streams(struct uas_dev_info *devinfo);
81 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
82 				int status);
83 
84 /*
85  * This driver needs its own workqueue, as we need to control memory allocation.
86  *
87  * In the course of error handling and power management uas_wait_for_pending_cmnds()
88  * needs to flush pending work items. In these contexts we cannot allocate memory
89  * by doing block IO as we would deadlock. For the same reason we cannot wait
90  * for anything allocating memory not heeding these constraints.
91  *
92  * So we have to control all work items that can be on the workqueue we flush.
93  * Hence we cannot share a queue and need our own.
94  */
95 static struct workqueue_struct *workqueue;
96 
uas_do_work(struct work_struct * work)97 static void uas_do_work(struct work_struct *work)
98 {
99 	struct uas_dev_info *devinfo =
100 		container_of(work, struct uas_dev_info, work);
101 	struct uas_cmd_info *cmdinfo;
102 	struct scsi_cmnd *cmnd;
103 	unsigned long flags;
104 	int i, err;
105 
106 	spin_lock_irqsave(&devinfo->lock, flags);
107 
108 	if (devinfo->resetting)
109 		goto out;
110 
111 	for (i = 0; i < devinfo->qdepth; i++) {
112 		if (!devinfo->cmnd[i])
113 			continue;
114 
115 		cmnd = devinfo->cmnd[i];
116 		cmdinfo = scsi_cmd_priv(cmnd);
117 
118 		if (!(cmdinfo->state & IS_IN_WORK_LIST))
119 			continue;
120 
121 		err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
122 		if (!err)
123 			cmdinfo->state &= ~IS_IN_WORK_LIST;
124 		else
125 			queue_work(workqueue, &devinfo->work);
126 	}
127 out:
128 	spin_unlock_irqrestore(&devinfo->lock, flags);
129 }
130 
uas_scan_work(struct work_struct * work)131 static void uas_scan_work(struct work_struct *work)
132 {
133 	struct uas_dev_info *devinfo =
134 		container_of(work, struct uas_dev_info, scan_work);
135 	struct Scsi_Host *shost = usb_get_intfdata(devinfo->intf);
136 
137 	dev_dbg(&devinfo->intf->dev, "starting scan\n");
138 	scsi_scan_host(shost);
139 	dev_dbg(&devinfo->intf->dev, "scan complete\n");
140 }
141 
uas_add_work(struct scsi_cmnd * cmnd)142 static void uas_add_work(struct scsi_cmnd *cmnd)
143 {
144 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
145 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
146 
147 	lockdep_assert_held(&devinfo->lock);
148 	cmdinfo->state |= IS_IN_WORK_LIST;
149 	queue_work(workqueue, &devinfo->work);
150 }
151 
uas_zap_pending(struct uas_dev_info * devinfo,int result)152 static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
153 {
154 	struct uas_cmd_info *cmdinfo;
155 	struct scsi_cmnd *cmnd;
156 	unsigned long flags;
157 	int i, err;
158 
159 	spin_lock_irqsave(&devinfo->lock, flags);
160 	for (i = 0; i < devinfo->qdepth; i++) {
161 		if (!devinfo->cmnd[i])
162 			continue;
163 
164 		cmnd = devinfo->cmnd[i];
165 		cmdinfo = scsi_cmd_priv(cmnd);
166 		uas_log_cmd_state(cmnd, __func__, 0);
167 		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
168 		cmdinfo->state &= ~COMMAND_INFLIGHT;
169 		cmnd->result = result << 16;
170 		err = uas_try_complete(cmnd, __func__);
171 		WARN_ON(err != 0);
172 	}
173 	spin_unlock_irqrestore(&devinfo->lock, flags);
174 }
175 
uas_sense(struct urb * urb,struct scsi_cmnd * cmnd)176 static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
177 {
178 	struct sense_iu *sense_iu = urb->transfer_buffer;
179 	struct scsi_device *sdev = cmnd->device;
180 
181 	if (urb->actual_length > 16) {
182 		unsigned len = be16_to_cpup(&sense_iu->len);
183 		if (len + 16 != urb->actual_length) {
184 			int newlen = min(len + 16, urb->actual_length) - 16;
185 			if (newlen < 0)
186 				newlen = 0;
187 			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
188 				"disagrees with IU sense data length %d, "
189 				"using %d bytes of sense data\n", __func__,
190 					urb->actual_length, len, newlen);
191 			len = newlen;
192 		}
193 		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
194 	}
195 
196 	cmnd->result = sense_iu->status;
197 }
198 
uas_log_cmd_state(struct scsi_cmnd * cmnd,const char * prefix,int status)199 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
200 			      int status)
201 {
202 	struct uas_cmd_info *ci = scsi_cmd_priv(cmnd);
203 
204 	if (status == -ENODEV) /* too late */
205 		return;
206 
207 	scmd_printk(KERN_INFO, cmnd,
208 		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
209 		    prefix, status, ci->uas_tag,
210 		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
211 		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
212 		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
213 		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
214 		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
215 		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
216 		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
217 		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
218 		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
219 		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
220 		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
221 		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
222 	scsi_print_command(cmnd);
223 }
224 
uas_free_unsubmitted_urbs(struct scsi_cmnd * cmnd)225 static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
226 {
227 	struct uas_cmd_info *cmdinfo;
228 
229 	if (!cmnd)
230 		return;
231 
232 	cmdinfo = scsi_cmd_priv(cmnd);
233 
234 	if (cmdinfo->state & SUBMIT_CMD_URB)
235 		usb_free_urb(cmdinfo->cmd_urb);
236 
237 	/* data urbs may have never gotten their submit flag set */
238 	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
239 		usb_free_urb(cmdinfo->data_in_urb);
240 	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
241 		usb_free_urb(cmdinfo->data_out_urb);
242 }
243 
uas_try_complete(struct scsi_cmnd * cmnd,const char * caller)244 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
245 {
246 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
247 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
248 
249 	lockdep_assert_held(&devinfo->lock);
250 	if (cmdinfo->state & (COMMAND_INFLIGHT |
251 			      DATA_IN_URB_INFLIGHT |
252 			      DATA_OUT_URB_INFLIGHT |
253 			      COMMAND_ABORTED))
254 		return -EBUSY;
255 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
256 	uas_free_unsubmitted_urbs(cmnd);
257 	scsi_done(cmnd);
258 	return 0;
259 }
260 
uas_xfer_data(struct urb * urb,struct scsi_cmnd * cmnd,unsigned direction)261 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
262 			  unsigned direction)
263 {
264 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
265 	int err;
266 
267 	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
268 	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
269 	if (err) {
270 		uas_add_work(cmnd);
271 	}
272 }
273 
uas_evaluate_response_iu(struct response_iu * riu,struct scsi_cmnd * cmnd)274 static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
275 {
276 	u8 response_code = riu->response_code;
277 
278 	switch (response_code) {
279 	case RC_INCORRECT_LUN:
280 		set_host_byte(cmnd, DID_BAD_TARGET);
281 		break;
282 	case RC_TMF_SUCCEEDED:
283 		set_host_byte(cmnd, DID_OK);
284 		break;
285 	case RC_TMF_NOT_SUPPORTED:
286 		set_host_byte(cmnd, DID_BAD_TARGET);
287 		break;
288 	default:
289 		uas_log_cmd_state(cmnd, "response iu", response_code);
290 		set_host_byte(cmnd, DID_ERROR);
291 		break;
292 	}
293 
294 	return response_code == RC_TMF_SUCCEEDED;
295 }
296 
uas_stat_cmplt(struct urb * urb)297 static void uas_stat_cmplt(struct urb *urb)
298 {
299 	struct iu *iu = urb->transfer_buffer;
300 	struct Scsi_Host *shost = urb->context;
301 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
302 	struct urb *data_in_urb = NULL;
303 	struct urb *data_out_urb = NULL;
304 	struct scsi_cmnd *cmnd;
305 	struct uas_cmd_info *cmdinfo;
306 	unsigned long flags;
307 	unsigned int idx;
308 	int status = urb->status;
309 	bool success;
310 
311 	spin_lock_irqsave(&devinfo->lock, flags);
312 
313 	if (devinfo->resetting)
314 		goto out;
315 
316 	if (status) {
317 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
318 			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
319 		goto out;
320 	}
321 
322 	idx = be16_to_cpup(&iu->tag) - 1;
323 	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
324 		dev_err(&urb->dev->dev,
325 			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
326 		goto out;
327 	}
328 
329 	cmnd = devinfo->cmnd[idx];
330 	cmdinfo = scsi_cmd_priv(cmnd);
331 
332 	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
333 		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
334 		goto out;
335 	}
336 
337 	switch (iu->iu_id) {
338 	case IU_ID_STATUS:
339 		uas_sense(urb, cmnd);
340 		if (cmnd->result != 0) {
341 			/* cancel data transfers on error */
342 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
343 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
344 		}
345 		cmdinfo->state &= ~COMMAND_INFLIGHT;
346 		uas_try_complete(cmnd, __func__);
347 		break;
348 	case IU_ID_READ_READY:
349 		if (!cmdinfo->data_in_urb ||
350 				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
351 			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
352 			break;
353 		}
354 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
355 		break;
356 	case IU_ID_WRITE_READY:
357 		if (!cmdinfo->data_out_urb ||
358 				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
359 			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
360 			break;
361 		}
362 		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
363 		break;
364 	case IU_ID_RESPONSE:
365 		cmdinfo->state &= ~COMMAND_INFLIGHT;
366 		success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
367 		if (!success) {
368 			/* Error, cancel data transfers */
369 			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
370 			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
371 		}
372 		uas_try_complete(cmnd, __func__);
373 		break;
374 	default:
375 		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
376 	}
377 out:
378 	usb_free_urb(urb);
379 	spin_unlock_irqrestore(&devinfo->lock, flags);
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 }
391 
uas_data_cmplt(struct urb * urb)392 static void uas_data_cmplt(struct urb *urb)
393 {
394 	struct scsi_cmnd *cmnd = urb->context;
395 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
396 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
397 	struct scsi_data_buffer *sdb = &cmnd->sdb;
398 	unsigned long flags;
399 	int status = urb->status;
400 
401 	spin_lock_irqsave(&devinfo->lock, flags);
402 
403 	if (cmdinfo->data_in_urb == urb) {
404 		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
405 		cmdinfo->data_in_urb = NULL;
406 	} else if (cmdinfo->data_out_urb == urb) {
407 		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
408 		cmdinfo->data_out_urb = NULL;
409 	}
410 
411 	if (devinfo->resetting)
412 		goto out;
413 
414 	/* Data urbs should not complete before the cmd urb is submitted */
415 	if (cmdinfo->state & SUBMIT_CMD_URB) {
416 		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
417 		goto out;
418 	}
419 
420 	if (status) {
421 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
422 			uas_log_cmd_state(cmnd, "data cmplt err", status);
423 		/* error: no data transfered */
424 		scsi_set_resid(cmnd, sdb->length);
425 	} else {
426 		scsi_set_resid(cmnd, sdb->length - urb->actual_length);
427 	}
428 	uas_try_complete(cmnd, __func__);
429 out:
430 	usb_free_urb(urb);
431 	spin_unlock_irqrestore(&devinfo->lock, flags);
432 }
433 
uas_cmd_cmplt(struct urb * urb)434 static void uas_cmd_cmplt(struct urb *urb)
435 {
436 	if (urb->status)
437 		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
438 
439 	usb_free_urb(urb);
440 }
441 
uas_alloc_data_urb(struct uas_dev_info * devinfo,gfp_t gfp,struct scsi_cmnd * cmnd,enum dma_data_direction dir)442 static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
443 				      struct scsi_cmnd *cmnd,
444 				      enum dma_data_direction dir)
445 {
446 	struct usb_device *udev = devinfo->udev;
447 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
448 	struct urb *urb = usb_alloc_urb(0, gfp);
449 	struct scsi_data_buffer *sdb = &cmnd->sdb;
450 	unsigned int pipe = (dir == DMA_FROM_DEVICE)
451 		? devinfo->data_in_pipe : devinfo->data_out_pipe;
452 
453 	if (!urb)
454 		goto out;
455 	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
456 			  uas_data_cmplt, cmnd);
457 	if (devinfo->use_streams)
458 		urb->stream_id = cmdinfo->uas_tag;
459 	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
460 	urb->sg = sdb->table.sgl;
461  out:
462 	return urb;
463 }
464 
uas_alloc_sense_urb(struct uas_dev_info * devinfo,gfp_t gfp,struct scsi_cmnd * cmnd)465 static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
466 				       struct scsi_cmnd *cmnd)
467 {
468 	struct usb_device *udev = devinfo->udev;
469 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
470 	struct urb *urb = usb_alloc_urb(0, gfp);
471 	struct sense_iu *iu;
472 
473 	if (!urb)
474 		goto out;
475 
476 	iu = kzalloc(sizeof(*iu), gfp);
477 	if (!iu)
478 		goto free;
479 
480 	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
481 			  uas_stat_cmplt, cmnd->device->host);
482 	if (devinfo->use_streams)
483 		urb->stream_id = cmdinfo->uas_tag;
484 	urb->transfer_flags |= URB_FREE_BUFFER;
485  out:
486 	return urb;
487  free:
488 	usb_free_urb(urb);
489 	return NULL;
490 }
491 
uas_alloc_cmd_urb(struct uas_dev_info * devinfo,gfp_t gfp,struct scsi_cmnd * cmnd)492 static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
493 					struct scsi_cmnd *cmnd)
494 {
495 	struct usb_device *udev = devinfo->udev;
496 	struct scsi_device *sdev = cmnd->device;
497 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
498 	struct urb *urb = usb_alloc_urb(0, gfp);
499 	struct command_iu *iu;
500 	int len;
501 
502 	if (!urb)
503 		goto out;
504 
505 	len = cmnd->cmd_len - 16;
506 	if (len < 0)
507 		len = 0;
508 	len = ALIGN(len, 4);
509 	iu = kzalloc(sizeof(*iu) + len, gfp);
510 	if (!iu)
511 		goto free;
512 
513 	iu->iu_id = IU_ID_COMMAND;
514 	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
515 	iu->prio_attr = UAS_SIMPLE_TAG;
516 	iu->len = len;
517 	int_to_scsilun(sdev->lun, &iu->lun);
518 	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
519 
520 	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
521 							uas_cmd_cmplt, NULL);
522 	urb->transfer_flags |= URB_FREE_BUFFER;
523  out:
524 	return urb;
525  free:
526 	usb_free_urb(urb);
527 	return NULL;
528 }
529 
530 /*
531  * Why should I request the Status IU before sending the Command IU?  Spec
532  * says to, but also says the device may receive them in any order.  Seems
533  * daft to me.
534  */
535 
uas_submit_sense_urb(struct scsi_cmnd * cmnd,gfp_t gfp)536 static int uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
537 {
538 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
539 	struct urb *urb;
540 	int err;
541 
542 	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
543 	if (!urb)
544 		return -ENOMEM;
545 	usb_anchor_urb(urb, &devinfo->sense_urbs);
546 	err = usb_submit_urb(urb, gfp);
547 	if (err) {
548 		usb_unanchor_urb(urb);
549 		uas_log_cmd_state(cmnd, "sense submit err", err);
550 		usb_free_urb(urb);
551 	}
552 	return err;
553 }
554 
uas_submit_urbs(struct scsi_cmnd * cmnd,struct uas_dev_info * devinfo)555 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
556 			   struct uas_dev_info *devinfo)
557 {
558 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
559 	int err;
560 
561 	lockdep_assert_held(&devinfo->lock);
562 	if (cmdinfo->state & SUBMIT_STATUS_URB) {
563 		err = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
564 		if (err)
565 			return err;
566 		cmdinfo->state &= ~SUBMIT_STATUS_URB;
567 	}
568 
569 	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
570 		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
571 							cmnd, DMA_FROM_DEVICE);
572 		if (!cmdinfo->data_in_urb)
573 			return -ENOMEM;
574 		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
575 	}
576 
577 	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
578 		usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
579 		err = usb_submit_urb(cmdinfo->data_in_urb, GFP_ATOMIC);
580 		if (err) {
581 			usb_unanchor_urb(cmdinfo->data_in_urb);
582 			uas_log_cmd_state(cmnd, "data in submit err", err);
583 			return err;
584 		}
585 		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
586 		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
587 	}
588 
589 	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
590 		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
591 							cmnd, DMA_TO_DEVICE);
592 		if (!cmdinfo->data_out_urb)
593 			return -ENOMEM;
594 		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
595 	}
596 
597 	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
598 		usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
599 		err = usb_submit_urb(cmdinfo->data_out_urb, GFP_ATOMIC);
600 		if (err) {
601 			usb_unanchor_urb(cmdinfo->data_out_urb);
602 			uas_log_cmd_state(cmnd, "data out submit err", err);
603 			return err;
604 		}
605 		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
606 		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
607 	}
608 
609 	if (cmdinfo->state & ALLOC_CMD_URB) {
610 		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
611 		if (!cmdinfo->cmd_urb)
612 			return -ENOMEM;
613 		cmdinfo->state &= ~ALLOC_CMD_URB;
614 	}
615 
616 	if (cmdinfo->state & SUBMIT_CMD_URB) {
617 		usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
618 		err = usb_submit_urb(cmdinfo->cmd_urb, GFP_ATOMIC);
619 		if (err) {
620 			usb_unanchor_urb(cmdinfo->cmd_urb);
621 			uas_log_cmd_state(cmnd, "cmd submit err", err);
622 			return err;
623 		}
624 		cmdinfo->cmd_urb = NULL;
625 		cmdinfo->state &= ~SUBMIT_CMD_URB;
626 		cmdinfo->state |= COMMAND_INFLIGHT;
627 	}
628 
629 	return 0;
630 }
631 
uas_queuecommand_lck(struct scsi_cmnd * cmnd)632 static int uas_queuecommand_lck(struct scsi_cmnd *cmnd)
633 {
634 	struct scsi_device *sdev = cmnd->device;
635 	struct uas_dev_info *devinfo = sdev->hostdata;
636 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
637 	unsigned long flags;
638 	int idx, err;
639 
640 	/* Re-check scsi_block_requests now that we've the host-lock */
641 	if (cmnd->device->host->host_self_blocked)
642 		return SCSI_MLQUEUE_DEVICE_BUSY;
643 
644 	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
645 			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
646 		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
647 		       sizeof(usb_stor_sense_invalidCDB));
648 		cmnd->result = SAM_STAT_CHECK_CONDITION;
649 		scsi_done(cmnd);
650 		return 0;
651 	}
652 
653 	spin_lock_irqsave(&devinfo->lock, flags);
654 
655 	if (devinfo->resetting) {
656 		set_host_byte(cmnd, DID_ERROR);
657 		scsi_done(cmnd);
658 		goto zombie;
659 	}
660 
661 	/* Find a free uas-tag */
662 	for (idx = 0; idx < devinfo->qdepth; idx++) {
663 		if (!devinfo->cmnd[idx])
664 			break;
665 	}
666 	if (idx == devinfo->qdepth) {
667 		spin_unlock_irqrestore(&devinfo->lock, flags);
668 		return SCSI_MLQUEUE_DEVICE_BUSY;
669 	}
670 
671 	memset(cmdinfo, 0, sizeof(*cmdinfo));
672 	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
673 	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
674 
675 	switch (cmnd->sc_data_direction) {
676 	case DMA_FROM_DEVICE:
677 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
678 		break;
679 	case DMA_BIDIRECTIONAL:
680 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
681 		fallthrough;
682 	case DMA_TO_DEVICE:
683 		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
684 		break;
685 	case DMA_NONE:
686 		break;
687 	}
688 
689 	if (!devinfo->use_streams)
690 		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
691 
692 	err = uas_submit_urbs(cmnd, devinfo);
693 	/*
694 	 * in case of fatal errors the SCSI layer is peculiar
695 	 * a command that has finished is a success for the purpose
696 	 * of queueing, no matter how fatal the error
697 	 */
698 	if (err == -ENODEV) {
699 		set_host_byte(cmnd, DID_NO_CONNECT);
700 		scsi_done(cmnd);
701 		goto zombie;
702 	}
703 	if (err) {
704 		/* If we did nothing, give up now */
705 		if (cmdinfo->state & SUBMIT_STATUS_URB) {
706 			spin_unlock_irqrestore(&devinfo->lock, flags);
707 			return SCSI_MLQUEUE_DEVICE_BUSY;
708 		}
709 		uas_add_work(cmnd);
710 	}
711 
712 	devinfo->cmnd[idx] = cmnd;
713 zombie:
714 	spin_unlock_irqrestore(&devinfo->lock, flags);
715 	return 0;
716 }
717 
DEF_SCSI_QCMD(uas_queuecommand)718 static DEF_SCSI_QCMD(uas_queuecommand)
719 
720 /*
721  * For now we do not support actually sending an abort to the device, so
722  * this eh always fails. Still we must define it to make sure that we've
723  * dropped all references to the cmnd in question once this function exits.
724  */
725 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
726 {
727 	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
728 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
729 	struct urb *data_in_urb = NULL;
730 	struct urb *data_out_urb = NULL;
731 	unsigned long flags;
732 
733 	spin_lock_irqsave(&devinfo->lock, flags);
734 
735 	uas_log_cmd_state(cmnd, __func__, 0);
736 
737 	/* Ensure that try_complete does not call scsi_done */
738 	cmdinfo->state |= COMMAND_ABORTED;
739 
740 	/* Drop all refs to this cmnd, kill data urbs to break their ref */
741 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
742 	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
743 		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
744 	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
745 		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
746 
747 	uas_free_unsubmitted_urbs(cmnd);
748 
749 	spin_unlock_irqrestore(&devinfo->lock, flags);
750 
751 	if (data_in_urb) {
752 		usb_kill_urb(data_in_urb);
753 		usb_put_urb(data_in_urb);
754 	}
755 	if (data_out_urb) {
756 		usb_kill_urb(data_out_urb);
757 		usb_put_urb(data_out_urb);
758 	}
759 
760 	return FAILED;
761 }
762 
uas_eh_device_reset_handler(struct scsi_cmnd * cmnd)763 static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
764 {
765 	struct scsi_device *sdev = cmnd->device;
766 	struct uas_dev_info *devinfo = sdev->hostdata;
767 	struct usb_device *udev = devinfo->udev;
768 	unsigned long flags;
769 	int err;
770 
771 	err = usb_lock_device_for_reset(udev, devinfo->intf);
772 	if (err) {
773 		shost_printk(KERN_ERR, sdev->host,
774 			     "%s FAILED to get lock err %d\n", __func__, err);
775 		return FAILED;
776 	}
777 
778 	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
779 
780 	spin_lock_irqsave(&devinfo->lock, flags);
781 	devinfo->resetting = 1;
782 	spin_unlock_irqrestore(&devinfo->lock, flags);
783 
784 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
785 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
786 	usb_kill_anchored_urbs(&devinfo->data_urbs);
787 	uas_zap_pending(devinfo, DID_RESET);
788 
789 	err = usb_reset_device(udev);
790 
791 	spin_lock_irqsave(&devinfo->lock, flags);
792 	devinfo->resetting = 0;
793 	spin_unlock_irqrestore(&devinfo->lock, flags);
794 
795 	usb_unlock_device(udev);
796 
797 	if (err) {
798 		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
799 			     __func__, err);
800 		return FAILED;
801 	}
802 
803 	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
804 	return SUCCESS;
805 }
806 
uas_target_alloc(struct scsi_target * starget)807 static int uas_target_alloc(struct scsi_target *starget)
808 {
809 	struct uas_dev_info *devinfo = (struct uas_dev_info *)
810 			dev_to_shost(starget->dev.parent)->hostdata;
811 
812 	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
813 		starget->no_report_luns = 1;
814 
815 	return 0;
816 }
817 
uas_slave_alloc(struct scsi_device * sdev)818 static int uas_slave_alloc(struct scsi_device *sdev)
819 {
820 	struct uas_dev_info *devinfo =
821 		(struct uas_dev_info *)sdev->host->hostdata;
822 
823 	sdev->hostdata = devinfo;
824 
825 	/*
826 	 * The protocol has no requirements on alignment in the strict sense.
827 	 * Controllers may or may not have alignment restrictions.
828 	 * As this is not exported, we use an extremely conservative guess.
829 	 */
830 	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
831 
832 	if (devinfo->flags & US_FL_MAX_SECTORS_64)
833 		blk_queue_max_hw_sectors(sdev->request_queue, 64);
834 	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
835 		blk_queue_max_hw_sectors(sdev->request_queue, 240);
836 
837 	return 0;
838 }
839 
uas_slave_configure(struct scsi_device * sdev)840 static int uas_slave_configure(struct scsi_device *sdev)
841 {
842 	struct uas_dev_info *devinfo = sdev->hostdata;
843 
844 	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
845 		sdev->no_report_opcodes = 1;
846 
847 	/* A few buggy USB-ATA bridges don't understand FUA */
848 	if (devinfo->flags & US_FL_BROKEN_FUA)
849 		sdev->broken_fua = 1;
850 
851 	/* UAS also needs to support FL_ALWAYS_SYNC */
852 	if (devinfo->flags & US_FL_ALWAYS_SYNC) {
853 		sdev->skip_ms_page_3f = 1;
854 		sdev->skip_ms_page_8 = 1;
855 		sdev->wce_default_on = 1;
856 	}
857 
858 	/* Some disks cannot handle READ_CAPACITY_16 */
859 	if (devinfo->flags & US_FL_NO_READ_CAPACITY_16)
860 		sdev->no_read_capacity_16 = 1;
861 
862 	/* Some disks cannot handle WRITE_SAME */
863 	if (devinfo->flags & US_FL_NO_SAME)
864 		sdev->no_write_same = 1;
865 	/*
866 	 * Some disks return the total number of blocks in response
867 	 * to READ CAPACITY rather than the highest block number.
868 	 * If this device makes that mistake, tell the sd driver.
869 	 */
870 	if (devinfo->flags & US_FL_FIX_CAPACITY)
871 		sdev->fix_capacity = 1;
872 
873 	/*
874 	 * in some cases we have to guess
875 	 */
876 	if (devinfo->flags & US_FL_CAPACITY_HEURISTICS)
877 		sdev->guess_capacity = 1;
878 
879 	/*
880 	 * Some devices report generic values until the media has been
881 	 * accessed. Force a READ(10) prior to querying device
882 	 * characteristics.
883 	 */
884 	sdev->read_before_ms = 1;
885 
886 	/*
887 	 * Some devices don't like MODE SENSE with page=0x3f,
888 	 * which is the command used for checking if a device
889 	 * is write-protected.  Now that we tell the sd driver
890 	 * to do a 192-byte transfer with this command the
891 	 * majority of devices work fine, but a few still can't
892 	 * handle it.  The sd driver will simply assume those
893 	 * devices are write-enabled.
894 	 */
895 	if (devinfo->flags & US_FL_NO_WP_DETECT)
896 		sdev->skip_ms_page_3f = 1;
897 
898 	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
899 	return 0;
900 }
901 
902 static const struct scsi_host_template uas_host_template = {
903 	.module = THIS_MODULE,
904 	.name = "uas",
905 	.queuecommand = uas_queuecommand,
906 	.target_alloc = uas_target_alloc,
907 	.slave_alloc = uas_slave_alloc,
908 	.slave_configure = uas_slave_configure,
909 	.eh_abort_handler = uas_eh_abort_handler,
910 	.eh_device_reset_handler = uas_eh_device_reset_handler,
911 	.this_id = -1,
912 	.skip_settle_delay = 1,
913 	.dma_boundary = PAGE_SIZE - 1,
914 	.cmd_size = sizeof(struct uas_cmd_info),
915 };
916 
917 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
918 		    vendorName, productName, useProtocol, useTransport, \
919 		    initFunction, flags) \
920 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
921 	.driver_info = (flags) }
922 
923 static struct usb_device_id uas_usb_ids[] = {
924 #	include "unusual_uas.h"
925 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
926 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
927 	{ }
928 };
929 MODULE_DEVICE_TABLE(usb, uas_usb_ids);
930 
931 #undef UNUSUAL_DEV
932 
uas_switch_interface(struct usb_device * udev,struct usb_interface * intf)933 static int uas_switch_interface(struct usb_device *udev,
934 				struct usb_interface *intf)
935 {
936 	struct usb_host_interface *alt;
937 
938 	alt = uas_find_uas_alt_setting(intf);
939 	if (!alt)
940 		return -ENODEV;
941 
942 	return usb_set_interface(udev, alt->desc.bInterfaceNumber,
943 			alt->desc.bAlternateSetting);
944 }
945 
uas_configure_endpoints(struct uas_dev_info * devinfo)946 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
947 {
948 	struct usb_host_endpoint *eps[4] = { };
949 	struct usb_device *udev = devinfo->udev;
950 	int r;
951 
952 	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
953 	if (r)
954 		return r;
955 
956 	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
957 					    usb_endpoint_num(&eps[0]->desc));
958 	devinfo->status_pipe = usb_rcvbulkpipe(udev,
959 					    usb_endpoint_num(&eps[1]->desc));
960 	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
961 					    usb_endpoint_num(&eps[2]->desc));
962 	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
963 					    usb_endpoint_num(&eps[3]->desc));
964 
965 	if (udev->speed < USB_SPEED_SUPER) {
966 		devinfo->qdepth = 32;
967 		devinfo->use_streams = 0;
968 	} else {
969 		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
970 						    3, MAX_CMNDS, GFP_NOIO);
971 		if (devinfo->qdepth < 0)
972 			return devinfo->qdepth;
973 		devinfo->use_streams = 1;
974 	}
975 
976 	return 0;
977 }
978 
uas_free_streams(struct uas_dev_info * devinfo)979 static void uas_free_streams(struct uas_dev_info *devinfo)
980 {
981 	struct usb_device *udev = devinfo->udev;
982 	struct usb_host_endpoint *eps[3];
983 
984 	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
985 	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
986 	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
987 	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
988 }
989 
uas_probe(struct usb_interface * intf,const struct usb_device_id * id)990 static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
991 {
992 	int result = -ENOMEM;
993 	struct Scsi_Host *shost = NULL;
994 	struct uas_dev_info *devinfo;
995 	struct usb_device *udev = interface_to_usbdev(intf);
996 	unsigned long dev_flags;
997 
998 	if (!uas_use_uas_driver(intf, id, &dev_flags))
999 		return -ENODEV;
1000 
1001 	if (uas_switch_interface(udev, intf))
1002 		return -ENODEV;
1003 
1004 	shost = scsi_host_alloc(&uas_host_template,
1005 				sizeof(struct uas_dev_info));
1006 	if (!shost)
1007 		goto set_alt0;
1008 
1009 	shost->max_cmd_len = 16 + 252;
1010 	shost->max_id = 1;
1011 	shost->max_lun = 256;
1012 	shost->max_channel = 0;
1013 	shost->sg_tablesize = udev->bus->sg_tablesize;
1014 
1015 	devinfo = (struct uas_dev_info *)shost->hostdata;
1016 	devinfo->intf = intf;
1017 	devinfo->udev = udev;
1018 	devinfo->resetting = 0;
1019 	devinfo->shutdown = 0;
1020 	devinfo->flags = dev_flags;
1021 	init_usb_anchor(&devinfo->cmd_urbs);
1022 	init_usb_anchor(&devinfo->sense_urbs);
1023 	init_usb_anchor(&devinfo->data_urbs);
1024 	spin_lock_init(&devinfo->lock);
1025 	INIT_WORK(&devinfo->work, uas_do_work);
1026 	INIT_WORK(&devinfo->scan_work, uas_scan_work);
1027 
1028 	result = uas_configure_endpoints(devinfo);
1029 	if (result)
1030 		goto set_alt0;
1031 
1032 	/*
1033 	 * 1 tag is reserved for untagged commands +
1034 	 * 1 tag to avoid off by one errors in some bridge firmwares
1035 	 */
1036 	shost->can_queue = devinfo->qdepth - 2;
1037 
1038 	usb_set_intfdata(intf, shost);
1039 	result = scsi_add_host(shost, &intf->dev);
1040 	if (result)
1041 		goto free_streams;
1042 
1043 	/* Submit the delayed_work for SCSI-device scanning */
1044 	schedule_work(&devinfo->scan_work);
1045 
1046 	return result;
1047 
1048 free_streams:
1049 	uas_free_streams(devinfo);
1050 	usb_set_intfdata(intf, NULL);
1051 set_alt0:
1052 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1053 	if (shost)
1054 		scsi_host_put(shost);
1055 	return result;
1056 }
1057 
uas_cmnd_list_empty(struct uas_dev_info * devinfo)1058 static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
1059 {
1060 	unsigned long flags;
1061 	int i, r = 1;
1062 
1063 	spin_lock_irqsave(&devinfo->lock, flags);
1064 
1065 	for (i = 0; i < devinfo->qdepth; i++) {
1066 		if (devinfo->cmnd[i]) {
1067 			r = 0; /* Not empty */
1068 			break;
1069 		}
1070 	}
1071 
1072 	spin_unlock_irqrestore(&devinfo->lock, flags);
1073 
1074 	return r;
1075 }
1076 
1077 /*
1078  * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
1079  * get empty while there still is more work to do due to sense-urbs completing
1080  * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
1081  */
uas_wait_for_pending_cmnds(struct uas_dev_info * devinfo)1082 static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
1083 {
1084 	unsigned long start_time;
1085 	int r;
1086 
1087 	start_time = jiffies;
1088 	do {
1089 		flush_work(&devinfo->work);
1090 
1091 		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1092 		if (r == 0)
1093 			return -ETIME;
1094 
1095 		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1096 		if (r == 0)
1097 			return -ETIME;
1098 
1099 		if (time_after(jiffies, start_time + 5 * HZ))
1100 			return -ETIME;
1101 	} while (!uas_cmnd_list_empty(devinfo));
1102 
1103 	return 0;
1104 }
1105 
uas_pre_reset(struct usb_interface * intf)1106 static int uas_pre_reset(struct usb_interface *intf)
1107 {
1108 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1109 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1110 	unsigned long flags;
1111 
1112 	if (devinfo->shutdown)
1113 		return 0;
1114 
1115 	/* Block new requests */
1116 	spin_lock_irqsave(shost->host_lock, flags);
1117 	scsi_block_requests(shost);
1118 	spin_unlock_irqrestore(shost->host_lock, flags);
1119 
1120 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1121 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1122 		scsi_unblock_requests(shost);
1123 		return 1;
1124 	}
1125 
1126 	uas_free_streams(devinfo);
1127 
1128 	return 0;
1129 }
1130 
uas_post_reset(struct usb_interface * intf)1131 static int uas_post_reset(struct usb_interface *intf)
1132 {
1133 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1134 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1135 	unsigned long flags;
1136 	int err;
1137 
1138 	if (devinfo->shutdown)
1139 		return 0;
1140 
1141 	err = uas_configure_endpoints(devinfo);
1142 	if (err && err != -ENODEV)
1143 		shost_printk(KERN_ERR, shost,
1144 			     "%s: alloc streams error %d after reset",
1145 			     __func__, err);
1146 
1147 	/* we must unblock the host in every case lest we deadlock */
1148 	spin_lock_irqsave(shost->host_lock, flags);
1149 	scsi_report_bus_reset(shost, 0);
1150 	spin_unlock_irqrestore(shost->host_lock, flags);
1151 
1152 	scsi_unblock_requests(shost);
1153 
1154 	return err ? 1 : 0;
1155 }
1156 
uas_suspend(struct usb_interface * intf,pm_message_t message)1157 static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1158 {
1159 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1160 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1161 
1162 	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1163 		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1164 		return -ETIME;
1165 	}
1166 
1167 	return 0;
1168 }
1169 
uas_resume(struct usb_interface * intf)1170 static int uas_resume(struct usb_interface *intf)
1171 {
1172 	return 0;
1173 }
1174 
uas_reset_resume(struct usb_interface * intf)1175 static int uas_reset_resume(struct usb_interface *intf)
1176 {
1177 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1178 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1179 	unsigned long flags;
1180 	int err;
1181 
1182 	err = uas_configure_endpoints(devinfo);
1183 	if (err) {
1184 		shost_printk(KERN_ERR, shost,
1185 			     "%s: alloc streams error %d after reset",
1186 			     __func__, err);
1187 		return -EIO;
1188 	}
1189 
1190 	spin_lock_irqsave(shost->host_lock, flags);
1191 	scsi_report_bus_reset(shost, 0);
1192 	spin_unlock_irqrestore(shost->host_lock, flags);
1193 
1194 	return 0;
1195 }
1196 
uas_disconnect(struct usb_interface * intf)1197 static void uas_disconnect(struct usb_interface *intf)
1198 {
1199 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1200 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1201 	unsigned long flags;
1202 
1203 	spin_lock_irqsave(&devinfo->lock, flags);
1204 	devinfo->resetting = 1;
1205 	spin_unlock_irqrestore(&devinfo->lock, flags);
1206 
1207 	cancel_work_sync(&devinfo->work);
1208 	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1209 	usb_kill_anchored_urbs(&devinfo->sense_urbs);
1210 	usb_kill_anchored_urbs(&devinfo->data_urbs);
1211 	uas_zap_pending(devinfo, DID_NO_CONNECT);
1212 
1213 	/*
1214 	 * Prevent SCSI scanning (if it hasn't started yet)
1215 	 * or wait for the SCSI-scanning routine to stop.
1216 	 */
1217 	cancel_work_sync(&devinfo->scan_work);
1218 
1219 	scsi_remove_host(shost);
1220 	uas_free_streams(devinfo);
1221 	scsi_host_put(shost);
1222 }
1223 
1224 /*
1225  * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1226  * hang on reboot when the device is still in uas mode. Note the reset is
1227  * necessary as some devices won't revert to usb-storage mode without it.
1228  */
uas_shutdown(struct device * dev)1229 static void uas_shutdown(struct device *dev)
1230 {
1231 	struct usb_interface *intf = to_usb_interface(dev);
1232 	struct usb_device *udev = interface_to_usbdev(intf);
1233 	struct Scsi_Host *shost = usb_get_intfdata(intf);
1234 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1235 
1236 	if (system_state != SYSTEM_RESTART)
1237 		return;
1238 
1239 	devinfo->shutdown = 1;
1240 	uas_free_streams(devinfo);
1241 	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1242 	usb_reset_device(udev);
1243 }
1244 
1245 static struct usb_driver uas_driver = {
1246 	.name = "uas",
1247 	.probe = uas_probe,
1248 	.disconnect = uas_disconnect,
1249 	.pre_reset = uas_pre_reset,
1250 	.post_reset = uas_post_reset,
1251 	.suspend = uas_suspend,
1252 	.resume = uas_resume,
1253 	.reset_resume = uas_reset_resume,
1254 	.drvwrap.driver.shutdown = uas_shutdown,
1255 	.id_table = uas_usb_ids,
1256 };
1257 
uas_init(void)1258 static int __init uas_init(void)
1259 {
1260 	int rv;
1261 
1262 	workqueue = alloc_workqueue("uas", WQ_MEM_RECLAIM, 0);
1263 	if (!workqueue)
1264 		return -ENOMEM;
1265 
1266 	rv = usb_register(&uas_driver);
1267 	if (rv) {
1268 		destroy_workqueue(workqueue);
1269 		return -ENOMEM;
1270 	}
1271 
1272 	return 0;
1273 }
1274 
uas_exit(void)1275 static void __exit uas_exit(void)
1276 {
1277 	usb_deregister(&uas_driver);
1278 	destroy_workqueue(workqueue);
1279 }
1280 
1281 module_init(uas_init);
1282 module_exit(uas_exit);
1283 
1284 MODULE_LICENSE("GPL");
1285 MODULE_IMPORT_NS(USB_STORAGE);
1286 MODULE_AUTHOR(
1287 	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");
1288