xref: /linux/drivers/usb/storage/usb.c (revision 2ba9268dd603d23e17643437b2246acb6844953b)
1 /* Driver for USB Mass Storage compliant devices
2  *
3  * Current development and maintenance by:
4  *   (c) 1999-2003 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5  *
6  * Developed with the assistance of:
7  *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
8  *   (c) 2003-2009 Alan Stern (stern@rowland.harvard.edu)
9  *
10  * Initial work by:
11  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
12  *
13  * usb_device_id support by Adam J. Richter (adam@yggdrasil.com):
14  *   (c) 2000 Yggdrasil Computing, Inc.
15  *
16  * This driver is based on the 'USB Mass Storage Class' document. This
17  * describes in detail the protocol used to communicate with such
18  * devices.  Clearly, the designers had SCSI and ATAPI commands in
19  * mind when they created this document.  The commands are all very
20  * similar to commands in the SCSI-II and ATAPI specifications.
21  *
22  * It is important to note that in a number of cases this class
23  * exhibits class-specific exemptions from the USB specification.
24  * Notably the usage of NAK, STALL and ACK differs from the norm, in
25  * that they are used to communicate wait, failed and OK on commands.
26  *
27  * Also, for certain devices, the interrupt endpoint is used to convey
28  * status of a command.
29  *
30  * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
31  * information about this driver.
32  *
33  * This program is free software; you can redistribute it and/or modify it
34  * under the terms of the GNU General Public License as published by the
35  * Free Software Foundation; either version 2, or (at your option) any
36  * later version.
37  *
38  * This program is distributed in the hope that it will be useful, but
39  * WITHOUT ANY WARRANTY; without even the implied warranty of
40  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
41  * General Public License for more details.
42  *
43  * You should have received a copy of the GNU General Public License along
44  * with this program; if not, write to the Free Software Foundation, Inc.,
45  * 675 Mass Ave, Cambridge, MA 02139, USA.
46  */
47 
48 #ifdef CONFIG_USB_STORAGE_DEBUG
49 #define DEBUG
50 #endif
51 
52 #include <linux/sched.h>
53 #include <linux/errno.h>
54 #include <linux/freezer.h>
55 #include <linux/module.h>
56 #include <linux/slab.h>
57 #include <linux/kthread.h>
58 #include <linux/mutex.h>
59 #include <linux/utsname.h>
60 
61 #include <scsi/scsi.h>
62 #include <scsi/scsi_cmnd.h>
63 #include <scsi/scsi_device.h>
64 
65 #include "usb.h"
66 #include "scsiglue.h"
67 #include "transport.h"
68 #include "protocol.h"
69 #include "debug.h"
70 #include "initializers.h"
71 
72 #include "sierra_ms.h"
73 #include "option_ms.h"
74 
75 #if IS_ENABLED(CONFIG_USB_UAS)
76 #include "uas-detect.h"
77 #endif
78 
79 /* Some informational data */
80 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
81 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
82 MODULE_LICENSE("GPL");
83 
84 static unsigned int delay_use = 1;
85 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
86 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
87 
88 static char quirks[128];
89 module_param_string(quirks, quirks, sizeof(quirks), S_IRUGO | S_IWUSR);
90 MODULE_PARM_DESC(quirks, "supplemental list of device IDs and their quirks");
91 
92 
93 /*
94  * The entries in this table correspond, line for line,
95  * with the entries in usb_storage_usb_ids[], defined in usual-tables.c.
96  */
97 
98 /* The vendor name should be kept at eight characters or less, and
99  * the product name should be kept at 16 characters or less. If a device
100  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
101  * normally generated by a device through the INQUIRY response will be
102  * taken from this list, and this is the reason for the above size
103  * restriction. However, if the flag is not present, then you
104  * are free to use as many characters as you like.
105  */
106 
107 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
108 		    vendor_name, product_name, use_protocol, use_transport, \
109 		    init_function, Flags) \
110 { \
111 	.vendorName = vendor_name,	\
112 	.productName = product_name,	\
113 	.useProtocol = use_protocol,	\
114 	.useTransport = use_transport,	\
115 	.initFunction = init_function,	\
116 }
117 
118 #define COMPLIANT_DEV	UNUSUAL_DEV
119 
120 #define USUAL_DEV(use_protocol, use_transport) \
121 { \
122 	.useProtocol = use_protocol,	\
123 	.useTransport = use_transport,	\
124 }
125 
126 #define UNUSUAL_VENDOR_INTF(idVendor, cl, sc, pr, \
127 		vendor_name, product_name, use_protocol, use_transport, \
128 		init_function, Flags) \
129 { \
130 	.vendorName = vendor_name,	\
131 	.productName = product_name,	\
132 	.useProtocol = use_protocol,	\
133 	.useTransport = use_transport,	\
134 	.initFunction = init_function,	\
135 }
136 
137 static struct us_unusual_dev us_unusual_dev_list[] = {
138 #	include "unusual_devs.h"
139 	{ }		/* Terminating entry */
140 };
141 
142 static struct us_unusual_dev for_dynamic_ids =
143 		USUAL_DEV(USB_SC_SCSI, USB_PR_BULK);
144 
145 #undef UNUSUAL_DEV
146 #undef COMPLIANT_DEV
147 #undef USUAL_DEV
148 #undef UNUSUAL_VENDOR_INTF
149 
150 #ifdef CONFIG_LOCKDEP
151 
152 static struct lock_class_key us_interface_key[USB_MAXINTERFACES];
153 
154 static void us_set_lock_class(struct mutex *mutex,
155 		struct usb_interface *intf)
156 {
157 	struct usb_device *udev = interface_to_usbdev(intf);
158 	struct usb_host_config *config = udev->actconfig;
159 	int i;
160 
161 	for (i = 0; i < config->desc.bNumInterfaces; i++) {
162 		if (config->interface[i] == intf)
163 			break;
164 	}
165 
166 	BUG_ON(i == config->desc.bNumInterfaces);
167 
168 	lockdep_set_class(mutex, &us_interface_key[i]);
169 }
170 
171 #else
172 
173 static void us_set_lock_class(struct mutex *mutex,
174 		struct usb_interface *intf)
175 {
176 }
177 
178 #endif
179 
180 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
181 
182 int usb_stor_suspend(struct usb_interface *iface, pm_message_t message)
183 {
184 	struct us_data *us = usb_get_intfdata(iface);
185 
186 	/* Wait until no command is running */
187 	mutex_lock(&us->dev_mutex);
188 
189 	if (us->suspend_resume_hook)
190 		(us->suspend_resume_hook)(us, US_SUSPEND);
191 
192 	/* When runtime PM is working, we'll set a flag to indicate
193 	 * whether we should autoresume when a SCSI request arrives. */
194 
195 	mutex_unlock(&us->dev_mutex);
196 	return 0;
197 }
198 EXPORT_SYMBOL_GPL(usb_stor_suspend);
199 
200 int usb_stor_resume(struct usb_interface *iface)
201 {
202 	struct us_data *us = usb_get_intfdata(iface);
203 
204 	mutex_lock(&us->dev_mutex);
205 
206 	if (us->suspend_resume_hook)
207 		(us->suspend_resume_hook)(us, US_RESUME);
208 
209 	mutex_unlock(&us->dev_mutex);
210 	return 0;
211 }
212 EXPORT_SYMBOL_GPL(usb_stor_resume);
213 
214 int usb_stor_reset_resume(struct usb_interface *iface)
215 {
216 	struct us_data *us = usb_get_intfdata(iface);
217 
218 	/* Report the reset to the SCSI core */
219 	usb_stor_report_bus_reset(us);
220 
221 	/* FIXME: Notify the subdrivers that they need to reinitialize
222 	 * the device */
223 	return 0;
224 }
225 EXPORT_SYMBOL_GPL(usb_stor_reset_resume);
226 
227 #endif /* CONFIG_PM */
228 
229 /*
230  * The next two routines get called just before and just after
231  * a USB port reset, whether from this driver or a different one.
232  */
233 
234 int usb_stor_pre_reset(struct usb_interface *iface)
235 {
236 	struct us_data *us = usb_get_intfdata(iface);
237 
238 	/* Make sure no command runs during the reset */
239 	mutex_lock(&us->dev_mutex);
240 	return 0;
241 }
242 EXPORT_SYMBOL_GPL(usb_stor_pre_reset);
243 
244 int usb_stor_post_reset(struct usb_interface *iface)
245 {
246 	struct us_data *us = usb_get_intfdata(iface);
247 
248 	/* Report the reset to the SCSI core */
249 	usb_stor_report_bus_reset(us);
250 
251 	/* FIXME: Notify the subdrivers that they need to reinitialize
252 	 * the device */
253 
254 	mutex_unlock(&us->dev_mutex);
255 	return 0;
256 }
257 EXPORT_SYMBOL_GPL(usb_stor_post_reset);
258 
259 /*
260  * fill_inquiry_response takes an unsigned char array (which must
261  * be at least 36 characters) and populates the vendor name,
262  * product name, and revision fields. Then the array is copied
263  * into the SCSI command's response buffer (oddly enough
264  * called request_buffer). data_len contains the length of the
265  * data array, which again must be at least 36.
266  */
267 
268 void fill_inquiry_response(struct us_data *us, unsigned char *data,
269 		unsigned int data_len)
270 {
271 	if (data_len < 36) /* You lose. */
272 		return;
273 
274 	memset(data+8, ' ', 28);
275 	if (data[0]&0x20) { /* USB device currently not connected. Return
276 			      peripheral qualifier 001b ("...however, the
277 			      physical device is not currently connected
278 			      to this logical unit") and leave vendor and
279 			      product identification empty. ("If the target
280 			      does store some of the INQUIRY data on the
281 			      device, it may return zeros or ASCII spaces
282 			      (20h) in those fields until the data is
283 			      available from the device."). */
284 	} else {
285 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
286 		int n;
287 
288 		n = strlen(us->unusual_dev->vendorName);
289 		memcpy(data+8, us->unusual_dev->vendorName, min(8, n));
290 		n = strlen(us->unusual_dev->productName);
291 		memcpy(data+16, us->unusual_dev->productName, min(16, n));
292 
293 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
294 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
295 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
296 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
297 	}
298 
299 	usb_stor_set_xfer_buf(data, data_len, us->srb);
300 }
301 EXPORT_SYMBOL_GPL(fill_inquiry_response);
302 
303 static int usb_stor_control_thread(void * __us)
304 {
305 	struct us_data *us = (struct us_data *)__us;
306 	struct Scsi_Host *host = us_to_host(us);
307 
308 	for (;;) {
309 		usb_stor_dbg(us, "*** thread sleeping\n");
310 		if (wait_for_completion_interruptible(&us->cmnd_ready))
311 			break;
312 
313 		usb_stor_dbg(us, "*** thread awakened\n");
314 
315 		/* lock the device pointers */
316 		mutex_lock(&(us->dev_mutex));
317 
318 		/* lock access to the state */
319 		scsi_lock(host);
320 
321 		/* When we are called with no command pending, we're done */
322 		if (us->srb == NULL) {
323 			scsi_unlock(host);
324 			mutex_unlock(&us->dev_mutex);
325 			usb_stor_dbg(us, "-- exiting\n");
326 			break;
327 		}
328 
329 		/* has the command timed out *already* ? */
330 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
331 			us->srb->result = DID_ABORT << 16;
332 			goto SkipForAbort;
333 		}
334 
335 		scsi_unlock(host);
336 
337 		/* reject the command if the direction indicator
338 		 * is UNKNOWN
339 		 */
340 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
341 			usb_stor_dbg(us, "UNKNOWN data direction\n");
342 			us->srb->result = DID_ERROR << 16;
343 		}
344 
345 		/* reject if target != 0 or if LUN is higher than
346 		 * the maximum known LUN
347 		 */
348 		else if (us->srb->device->id &&
349 				!(us->fflags & US_FL_SCM_MULT_TARG)) {
350 			usb_stor_dbg(us, "Bad target number (%d:%llu)\n",
351 				     us->srb->device->id,
352 				     us->srb->device->lun);
353 			us->srb->result = DID_BAD_TARGET << 16;
354 		}
355 
356 		else if (us->srb->device->lun > us->max_lun) {
357 			usb_stor_dbg(us, "Bad LUN (%d:%llu)\n",
358 				     us->srb->device->id,
359 				     us->srb->device->lun);
360 			us->srb->result = DID_BAD_TARGET << 16;
361 		}
362 
363 		/* Handle those devices which need us to fake
364 		 * their inquiry data */
365 		else if ((us->srb->cmnd[0] == INQUIRY) &&
366 			    (us->fflags & US_FL_FIX_INQUIRY)) {
367 			unsigned char data_ptr[36] = {
368 			    0x00, 0x80, 0x02, 0x02,
369 			    0x1F, 0x00, 0x00, 0x00};
370 
371 			usb_stor_dbg(us, "Faking INQUIRY command\n");
372 			fill_inquiry_response(us, data_ptr, 36);
373 			us->srb->result = SAM_STAT_GOOD;
374 		}
375 
376 		/* we've got a command, let's do it! */
377 		else {
378 			US_DEBUG(usb_stor_show_command(us, us->srb));
379 			us->proto_handler(us->srb, us);
380 			usb_mark_last_busy(us->pusb_dev);
381 		}
382 
383 		/* lock access to the state */
384 		scsi_lock(host);
385 
386 		/* indicate that the command is done */
387 		if (us->srb->result != DID_ABORT << 16) {
388 			usb_stor_dbg(us, "scsi cmd done, result=0x%x\n",
389 				     us->srb->result);
390 			us->srb->scsi_done(us->srb);
391 		} else {
392 SkipForAbort:
393 			usb_stor_dbg(us, "scsi command aborted\n");
394 		}
395 
396 		/* If an abort request was received we need to signal that
397 		 * the abort has finished.  The proper test for this is
398 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
399 		 * the timeout might have occurred after the command had
400 		 * already completed with a different result code. */
401 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
402 			complete(&(us->notify));
403 
404 			/* Allow USB transfers to resume */
405 			clear_bit(US_FLIDX_ABORTING, &us->dflags);
406 			clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
407 		}
408 
409 		/* finished working on this command */
410 		us->srb = NULL;
411 		scsi_unlock(host);
412 
413 		/* unlock the device pointers */
414 		mutex_unlock(&us->dev_mutex);
415 	} /* for (;;) */
416 
417 	/* Wait until we are told to stop */
418 	for (;;) {
419 		set_current_state(TASK_INTERRUPTIBLE);
420 		if (kthread_should_stop())
421 			break;
422 		schedule();
423 	}
424 	__set_current_state(TASK_RUNNING);
425 	return 0;
426 }
427 
428 /***********************************************************************
429  * Device probing and disconnecting
430  ***********************************************************************/
431 
432 /* Associate our private data with the USB device */
433 static int associate_dev(struct us_data *us, struct usb_interface *intf)
434 {
435 	/* Fill in the device-related fields */
436 	us->pusb_dev = interface_to_usbdev(intf);
437 	us->pusb_intf = intf;
438 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
439 	usb_stor_dbg(us, "Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
440 		     le16_to_cpu(us->pusb_dev->descriptor.idVendor),
441 		     le16_to_cpu(us->pusb_dev->descriptor.idProduct),
442 		     le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
443 	usb_stor_dbg(us, "Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
444 		     intf->cur_altsetting->desc.bInterfaceSubClass,
445 		     intf->cur_altsetting->desc.bInterfaceProtocol);
446 
447 	/* Store our private data in the interface */
448 	usb_set_intfdata(intf, us);
449 
450 	/* Allocate the control/setup and DMA-mapped buffers */
451 	us->cr = kmalloc(sizeof(*us->cr), GFP_KERNEL);
452 	if (!us->cr)
453 		return -ENOMEM;
454 
455 	us->iobuf = usb_alloc_coherent(us->pusb_dev, US_IOBUF_SIZE,
456 			GFP_KERNEL, &us->iobuf_dma);
457 	if (!us->iobuf) {
458 		usb_stor_dbg(us, "I/O buffer allocation failed\n");
459 		return -ENOMEM;
460 	}
461 	return 0;
462 }
463 
464 /* Works only for digits and letters, but small and fast */
465 #define TOLOWER(x) ((x) | 0x20)
466 
467 /* Adjust device flags based on the "quirks=" module parameter */
468 void usb_stor_adjust_quirks(struct usb_device *udev, unsigned long *fflags)
469 {
470 	char *p;
471 	u16 vid = le16_to_cpu(udev->descriptor.idVendor);
472 	u16 pid = le16_to_cpu(udev->descriptor.idProduct);
473 	unsigned f = 0;
474 	unsigned int mask = (US_FL_SANE_SENSE | US_FL_BAD_SENSE |
475 			US_FL_FIX_CAPACITY | US_FL_IGNORE_UAS |
476 			US_FL_CAPACITY_HEURISTICS | US_FL_IGNORE_DEVICE |
477 			US_FL_NOT_LOCKABLE | US_FL_MAX_SECTORS_64 |
478 			US_FL_CAPACITY_OK | US_FL_IGNORE_RESIDUE |
479 			US_FL_SINGLE_LUN | US_FL_NO_WP_DETECT |
480 			US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 |
481 			US_FL_INITIAL_READ10 | US_FL_WRITE_CACHE |
482 			US_FL_NO_ATA_1X | US_FL_NO_REPORT_OPCODES);
483 
484 	p = quirks;
485 	while (*p) {
486 		/* Each entry consists of VID:PID:flags */
487 		if (vid == simple_strtoul(p, &p, 16) &&
488 				*p == ':' &&
489 				pid == simple_strtoul(p+1, &p, 16) &&
490 				*p == ':')
491 			break;
492 
493 		/* Move forward to the next entry */
494 		while (*p) {
495 			if (*p++ == ',')
496 				break;
497 		}
498 	}
499 	if (!*p)	/* No match */
500 		return;
501 
502 	/* Collect the flags */
503 	while (*++p && *p != ',') {
504 		switch (TOLOWER(*p)) {
505 		case 'a':
506 			f |= US_FL_SANE_SENSE;
507 			break;
508 		case 'b':
509 			f |= US_FL_BAD_SENSE;
510 			break;
511 		case 'c':
512 			f |= US_FL_FIX_CAPACITY;
513 			break;
514 		case 'd':
515 			f |= US_FL_NO_READ_DISC_INFO;
516 			break;
517 		case 'e':
518 			f |= US_FL_NO_READ_CAPACITY_16;
519 			break;
520 		case 'f':
521 			f |= US_FL_NO_REPORT_OPCODES;
522 			break;
523 		case 'h':
524 			f |= US_FL_CAPACITY_HEURISTICS;
525 			break;
526 		case 'i':
527 			f |= US_FL_IGNORE_DEVICE;
528 			break;
529 		case 'l':
530 			f |= US_FL_NOT_LOCKABLE;
531 			break;
532 		case 'm':
533 			f |= US_FL_MAX_SECTORS_64;
534 			break;
535 		case 'n':
536 			f |= US_FL_INITIAL_READ10;
537 			break;
538 		case 'o':
539 			f |= US_FL_CAPACITY_OK;
540 			break;
541 		case 'p':
542 			f |= US_FL_WRITE_CACHE;
543 			break;
544 		case 'r':
545 			f |= US_FL_IGNORE_RESIDUE;
546 			break;
547 		case 's':
548 			f |= US_FL_SINGLE_LUN;
549 			break;
550 		case 't':
551 			f |= US_FL_NO_ATA_1X;
552 			break;
553 		case 'u':
554 			f |= US_FL_IGNORE_UAS;
555 			break;
556 		case 'w':
557 			f |= US_FL_NO_WP_DETECT;
558 			break;
559 		/* Ignore unrecognized flag characters */
560 		}
561 	}
562 	*fflags = (*fflags & ~mask) | f;
563 }
564 EXPORT_SYMBOL_GPL(usb_stor_adjust_quirks);
565 
566 /* Get the unusual_devs entries and the string descriptors */
567 static int get_device_info(struct us_data *us, const struct usb_device_id *id,
568 		struct us_unusual_dev *unusual_dev)
569 {
570 	struct usb_device *dev = us->pusb_dev;
571 	struct usb_interface_descriptor *idesc =
572 		&us->pusb_intf->cur_altsetting->desc;
573 	struct device *pdev = &us->pusb_intf->dev;
574 
575 	/* Store the entries */
576 	us->unusual_dev = unusual_dev;
577 	us->subclass = (unusual_dev->useProtocol == USB_SC_DEVICE) ?
578 			idesc->bInterfaceSubClass :
579 			unusual_dev->useProtocol;
580 	us->protocol = (unusual_dev->useTransport == USB_PR_DEVICE) ?
581 			idesc->bInterfaceProtocol :
582 			unusual_dev->useTransport;
583 	us->fflags = id->driver_info;
584 	usb_stor_adjust_quirks(us->pusb_dev, &us->fflags);
585 
586 	if (us->fflags & US_FL_IGNORE_DEVICE) {
587 		dev_info(pdev, "device ignored\n");
588 		return -ENODEV;
589 	}
590 
591 	/*
592 	 * This flag is only needed when we're in high-speed, so let's
593 	 * disable it if we're in full-speed
594 	 */
595 	if (dev->speed != USB_SPEED_HIGH)
596 		us->fflags &= ~US_FL_GO_SLOW;
597 
598 	if (us->fflags)
599 		dev_info(pdev, "Quirks match for vid %04x pid %04x: %lx\n",
600 				le16_to_cpu(dev->descriptor.idVendor),
601 				le16_to_cpu(dev->descriptor.idProduct),
602 				us->fflags);
603 
604 	/* Log a message if a non-generic unusual_dev entry contains an
605 	 * unnecessary subclass or protocol override.  This may stimulate
606 	 * reports from users that will help us remove unneeded entries
607 	 * from the unusual_devs.h table.
608 	 */
609 	if (id->idVendor || id->idProduct) {
610 		static const char *msgs[3] = {
611 			"an unneeded SubClass entry",
612 			"an unneeded Protocol entry",
613 			"unneeded SubClass and Protocol entries"};
614 		struct usb_device_descriptor *ddesc = &dev->descriptor;
615 		int msg = -1;
616 
617 		if (unusual_dev->useProtocol != USB_SC_DEVICE &&
618 			us->subclass == idesc->bInterfaceSubClass)
619 			msg += 1;
620 		if (unusual_dev->useTransport != USB_PR_DEVICE &&
621 			us->protocol == idesc->bInterfaceProtocol)
622 			msg += 2;
623 		if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
624 			dev_notice(pdev, "This device "
625 					"(%04x,%04x,%04x S %02x P %02x)"
626 					" has %s in unusual_devs.h (kernel"
627 					" %s)\n"
628 					"   Please send a copy of this message to "
629 					"<linux-usb@vger.kernel.org> and "
630 					"<usb-storage@lists.one-eyed-alien.net>\n",
631 					le16_to_cpu(ddesc->idVendor),
632 					le16_to_cpu(ddesc->idProduct),
633 					le16_to_cpu(ddesc->bcdDevice),
634 					idesc->bInterfaceSubClass,
635 					idesc->bInterfaceProtocol,
636 					msgs[msg],
637 					utsname()->release);
638 	}
639 
640 	return 0;
641 }
642 
643 /* Get the transport settings */
644 static void get_transport(struct us_data *us)
645 {
646 	switch (us->protocol) {
647 	case USB_PR_CB:
648 		us->transport_name = "Control/Bulk";
649 		us->transport = usb_stor_CB_transport;
650 		us->transport_reset = usb_stor_CB_reset;
651 		us->max_lun = 7;
652 		break;
653 
654 	case USB_PR_CBI:
655 		us->transport_name = "Control/Bulk/Interrupt";
656 		us->transport = usb_stor_CB_transport;
657 		us->transport_reset = usb_stor_CB_reset;
658 		us->max_lun = 7;
659 		break;
660 
661 	case USB_PR_BULK:
662 		us->transport_name = "Bulk";
663 		us->transport = usb_stor_Bulk_transport;
664 		us->transport_reset = usb_stor_Bulk_reset;
665 		break;
666 	}
667 }
668 
669 /* Get the protocol settings */
670 static void get_protocol(struct us_data *us)
671 {
672 	switch (us->subclass) {
673 	case USB_SC_RBC:
674 		us->protocol_name = "Reduced Block Commands (RBC)";
675 		us->proto_handler = usb_stor_transparent_scsi_command;
676 		break;
677 
678 	case USB_SC_8020:
679 		us->protocol_name = "8020i";
680 		us->proto_handler = usb_stor_pad12_command;
681 		us->max_lun = 0;
682 		break;
683 
684 	case USB_SC_QIC:
685 		us->protocol_name = "QIC-157";
686 		us->proto_handler = usb_stor_pad12_command;
687 		us->max_lun = 0;
688 		break;
689 
690 	case USB_SC_8070:
691 		us->protocol_name = "8070i";
692 		us->proto_handler = usb_stor_pad12_command;
693 		us->max_lun = 0;
694 		break;
695 
696 	case USB_SC_SCSI:
697 		us->protocol_name = "Transparent SCSI";
698 		us->proto_handler = usb_stor_transparent_scsi_command;
699 		break;
700 
701 	case USB_SC_UFI:
702 		us->protocol_name = "Uniform Floppy Interface (UFI)";
703 		us->proto_handler = usb_stor_ufi_command;
704 		break;
705 	}
706 }
707 
708 /* Get the pipe settings */
709 static int get_pipes(struct us_data *us)
710 {
711 	struct usb_host_interface *altsetting =
712 		us->pusb_intf->cur_altsetting;
713 	int i;
714 	struct usb_endpoint_descriptor *ep;
715 	struct usb_endpoint_descriptor *ep_in = NULL;
716 	struct usb_endpoint_descriptor *ep_out = NULL;
717 	struct usb_endpoint_descriptor *ep_int = NULL;
718 
719 	/*
720 	 * Find the first endpoint of each type we need.
721 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
722 	 * An optional interrupt-in is OK (necessary for CBI protocol).
723 	 * We will ignore any others.
724 	 */
725 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
726 		ep = &altsetting->endpoint[i].desc;
727 
728 		if (usb_endpoint_xfer_bulk(ep)) {
729 			if (usb_endpoint_dir_in(ep)) {
730 				if (!ep_in)
731 					ep_in = ep;
732 			} else {
733 				if (!ep_out)
734 					ep_out = ep;
735 			}
736 		}
737 
738 		else if (usb_endpoint_is_int_in(ep)) {
739 			if (!ep_int)
740 				ep_int = ep;
741 		}
742 	}
743 
744 	if (!ep_in || !ep_out || (us->protocol == USB_PR_CBI && !ep_int)) {
745 		usb_stor_dbg(us, "Endpoint sanity check failed! Rejecting dev.\n");
746 		return -EIO;
747 	}
748 
749 	/* Calculate and store the pipe values */
750 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
751 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
752 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
753 		usb_endpoint_num(ep_out));
754 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
755 		usb_endpoint_num(ep_in));
756 	if (ep_int) {
757 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
758 			usb_endpoint_num(ep_int));
759 		us->ep_bInterval = ep_int->bInterval;
760 	}
761 	return 0;
762 }
763 
764 /* Initialize all the dynamic resources we need */
765 static int usb_stor_acquire_resources(struct us_data *us)
766 {
767 	int p;
768 	struct task_struct *th;
769 
770 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
771 	if (!us->current_urb) {
772 		usb_stor_dbg(us, "URB allocation failed\n");
773 		return -ENOMEM;
774 	}
775 
776 	/* Just before we start our control thread, initialize
777 	 * the device if it needs initialization */
778 	if (us->unusual_dev->initFunction) {
779 		p = us->unusual_dev->initFunction(us);
780 		if (p)
781 			return p;
782 	}
783 
784 	/* Start up our control thread */
785 	th = kthread_run(usb_stor_control_thread, us, "usb-storage");
786 	if (IS_ERR(th)) {
787 		dev_warn(&us->pusb_intf->dev,
788 				"Unable to start control thread\n");
789 		return PTR_ERR(th);
790 	}
791 	us->ctl_thread = th;
792 
793 	return 0;
794 }
795 
796 /* Release all our dynamic resources */
797 static void usb_stor_release_resources(struct us_data *us)
798 {
799 	/* Tell the control thread to exit.  The SCSI host must
800 	 * already have been removed and the DISCONNECTING flag set
801 	 * so that we won't accept any more commands.
802 	 */
803 	usb_stor_dbg(us, "-- sending exit command to thread\n");
804 	complete(&us->cmnd_ready);
805 	if (us->ctl_thread)
806 		kthread_stop(us->ctl_thread);
807 
808 	/* Call the destructor routine, if it exists */
809 	if (us->extra_destructor) {
810 		usb_stor_dbg(us, "-- calling extra_destructor()\n");
811 		us->extra_destructor(us->extra);
812 	}
813 
814 	/* Free the extra data and the URB */
815 	kfree(us->extra);
816 	usb_free_urb(us->current_urb);
817 }
818 
819 /* Dissociate from the USB device */
820 static void dissociate_dev(struct us_data *us)
821 {
822 	/* Free the buffers */
823 	kfree(us->cr);
824 	usb_free_coherent(us->pusb_dev, US_IOBUF_SIZE, us->iobuf, us->iobuf_dma);
825 
826 	/* Remove our private data from the interface */
827 	usb_set_intfdata(us->pusb_intf, NULL);
828 }
829 
830 /* First stage of disconnect processing: stop SCSI scanning,
831  * remove the host, and stop accepting new commands
832  */
833 static void quiesce_and_remove_host(struct us_data *us)
834 {
835 	struct Scsi_Host *host = us_to_host(us);
836 
837 	/* If the device is really gone, cut short reset delays */
838 	if (us->pusb_dev->state == USB_STATE_NOTATTACHED) {
839 		set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
840 		wake_up(&us->delay_wait);
841 	}
842 
843 	/* Prevent SCSI scanning (if it hasn't started yet)
844 	 * or wait for the SCSI-scanning routine to stop.
845 	 */
846 	cancel_delayed_work_sync(&us->scan_dwork);
847 
848 	/* Balance autopm calls if scanning was cancelled */
849 	if (test_bit(US_FLIDX_SCAN_PENDING, &us->dflags))
850 		usb_autopm_put_interface_no_suspend(us->pusb_intf);
851 
852 	/* Removing the host will perform an orderly shutdown: caches
853 	 * synchronized, disks spun down, etc.
854 	 */
855 	scsi_remove_host(host);
856 
857 	/* Prevent any new commands from being accepted and cut short
858 	 * reset delays.
859 	 */
860 	scsi_lock(host);
861 	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
862 	scsi_unlock(host);
863 	wake_up(&us->delay_wait);
864 }
865 
866 /* Second stage of disconnect processing: deallocate all resources */
867 static void release_everything(struct us_data *us)
868 {
869 	usb_stor_release_resources(us);
870 	dissociate_dev(us);
871 
872 	/* Drop our reference to the host; the SCSI core will free it
873 	 * (and "us" along with it) when the refcount becomes 0. */
874 	scsi_host_put(us_to_host(us));
875 }
876 
877 /* Delayed-work routine to carry out SCSI-device scanning */
878 static void usb_stor_scan_dwork(struct work_struct *work)
879 {
880 	struct us_data *us = container_of(work, struct us_data,
881 			scan_dwork.work);
882 	struct device *dev = &us->pusb_intf->dev;
883 
884 	dev_dbg(dev, "starting scan\n");
885 
886 	/* For bulk-only devices, determine the max LUN value */
887 	if (us->protocol == USB_PR_BULK &&
888 	    !(us->fflags & US_FL_SINGLE_LUN) &&
889 	    !(us->fflags & US_FL_SCM_MULT_TARG)) {
890 		mutex_lock(&us->dev_mutex);
891 		us->max_lun = usb_stor_Bulk_max_lun(us);
892 		/*
893 		 * Allow proper scanning of devices that present more than 8 LUNs
894 		 * While not affecting other devices that may need the previous behavior
895 		 */
896 		if (us->max_lun >= 8)
897 			us_to_host(us)->max_lun = us->max_lun+1;
898 		mutex_unlock(&us->dev_mutex);
899 	}
900 	scsi_scan_host(us_to_host(us));
901 	dev_dbg(dev, "scan complete\n");
902 
903 	/* Should we unbind if no devices were detected? */
904 
905 	usb_autopm_put_interface(us->pusb_intf);
906 	clear_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
907 }
908 
909 static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
910 {
911 	struct usb_device *usb_dev = interface_to_usbdev(intf);
912 
913 	if (usb_dev->bus->sg_tablesize) {
914 		return usb_dev->bus->sg_tablesize;
915 	}
916 	return SG_ALL;
917 }
918 
919 /* First part of general USB mass-storage probing */
920 int usb_stor_probe1(struct us_data **pus,
921 		struct usb_interface *intf,
922 		const struct usb_device_id *id,
923 		struct us_unusual_dev *unusual_dev)
924 {
925 	struct Scsi_Host *host;
926 	struct us_data *us;
927 	int result;
928 
929 	dev_info(&intf->dev, "USB Mass Storage device detected\n");
930 
931 	/*
932 	 * Ask the SCSI layer to allocate a host structure, with extra
933 	 * space at the end for our private us_data structure.
934 	 */
935 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
936 	if (!host) {
937 		dev_warn(&intf->dev, "Unable to allocate the scsi host\n");
938 		return -ENOMEM;
939 	}
940 
941 	/*
942 	 * Allow 16-byte CDBs and thus > 2TB
943 	 */
944 	host->max_cmd_len = 16;
945 	host->sg_tablesize = usb_stor_sg_tablesize(intf);
946 	*pus = us = host_to_us(host);
947 	mutex_init(&(us->dev_mutex));
948 	us_set_lock_class(&us->dev_mutex, intf);
949 	init_completion(&us->cmnd_ready);
950 	init_completion(&(us->notify));
951 	init_waitqueue_head(&us->delay_wait);
952 	INIT_DELAYED_WORK(&us->scan_dwork, usb_stor_scan_dwork);
953 
954 	/* Associate the us_data structure with the USB device */
955 	result = associate_dev(us, intf);
956 	if (result)
957 		goto BadDevice;
958 
959 	/* Get the unusual_devs entries and the descriptors */
960 	result = get_device_info(us, id, unusual_dev);
961 	if (result)
962 		goto BadDevice;
963 
964 	/* Get standard transport and protocol settings */
965 	get_transport(us);
966 	get_protocol(us);
967 
968 	/* Give the caller a chance to fill in specialized transport
969 	 * or protocol settings.
970 	 */
971 	return 0;
972 
973 BadDevice:
974 	usb_stor_dbg(us, "storage_probe() failed\n");
975 	release_everything(us);
976 	return result;
977 }
978 EXPORT_SYMBOL_GPL(usb_stor_probe1);
979 
980 /* Second part of general USB mass-storage probing */
981 int usb_stor_probe2(struct us_data *us)
982 {
983 	int result;
984 	struct device *dev = &us->pusb_intf->dev;
985 
986 	/* Make sure the transport and protocol have both been set */
987 	if (!us->transport || !us->proto_handler) {
988 		result = -ENXIO;
989 		goto BadDevice;
990 	}
991 	usb_stor_dbg(us, "Transport: %s\n", us->transport_name);
992 	usb_stor_dbg(us, "Protocol: %s\n", us->protocol_name);
993 
994 	if (us->fflags & US_FL_SCM_MULT_TARG) {
995 		/*
996 		 * SCM eUSCSI bridge devices can have different numbers
997 		 * of LUNs on different targets; allow all to be probed.
998 		 */
999 		us->max_lun = 7;
1000 		/* The eUSCSI itself has ID 7, so avoid scanning that */
1001 		us_to_host(us)->this_id = 7;
1002 		/* max_id is 8 initially, so no need to set it here */
1003 	} else {
1004 		/* In the normal case there is only a single target */
1005 		us_to_host(us)->max_id = 1;
1006 		/*
1007 		 * Like Windows, we won't store the LUN bits in CDB[1] for
1008 		 * SCSI-2 devices using the Bulk-Only transport (even though
1009 		 * this violates the SCSI spec).
1010 		 */
1011 		if (us->transport == usb_stor_Bulk_transport)
1012 			us_to_host(us)->no_scsi2_lun_in_cdb = 1;
1013 	}
1014 
1015 	/* fix for single-lun devices */
1016 	if (us->fflags & US_FL_SINGLE_LUN)
1017 		us->max_lun = 0;
1018 
1019 	/* Find the endpoints and calculate pipe values */
1020 	result = get_pipes(us);
1021 	if (result)
1022 		goto BadDevice;
1023 
1024 	/*
1025 	 * If the device returns invalid data for the first READ(10)
1026 	 * command, indicate the command should be retried.
1027 	 */
1028 	if (us->fflags & US_FL_INITIAL_READ10)
1029 		set_bit(US_FLIDX_REDO_READ10, &us->dflags);
1030 
1031 	/* Acquire all the other resources and add the host */
1032 	result = usb_stor_acquire_resources(us);
1033 	if (result)
1034 		goto BadDevice;
1035 	snprintf(us->scsi_name, sizeof(us->scsi_name), "usb-storage %s",
1036 					dev_name(&us->pusb_intf->dev));
1037 	result = scsi_add_host(us_to_host(us), dev);
1038 	if (result) {
1039 		dev_warn(dev,
1040 				"Unable to add the scsi host\n");
1041 		goto BadDevice;
1042 	}
1043 
1044 	/* Submit the delayed_work for SCSI-device scanning */
1045 	usb_autopm_get_interface_no_resume(us->pusb_intf);
1046 	set_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
1047 
1048 	if (delay_use > 0)
1049 		dev_dbg(dev, "waiting for device to settle before scanning\n");
1050 	queue_delayed_work(system_freezable_wq, &us->scan_dwork,
1051 			delay_use * HZ);
1052 	return 0;
1053 
1054 	/* We come here if there are any problems */
1055 BadDevice:
1056 	usb_stor_dbg(us, "storage_probe() failed\n");
1057 	release_everything(us);
1058 	return result;
1059 }
1060 EXPORT_SYMBOL_GPL(usb_stor_probe2);
1061 
1062 /* Handle a USB mass-storage disconnect */
1063 void usb_stor_disconnect(struct usb_interface *intf)
1064 {
1065 	struct us_data *us = usb_get_intfdata(intf);
1066 
1067 	quiesce_and_remove_host(us);
1068 	release_everything(us);
1069 }
1070 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
1071 
1072 /* The main probe routine for standard devices */
1073 static int storage_probe(struct usb_interface *intf,
1074 			 const struct usb_device_id *id)
1075 {
1076 	struct us_unusual_dev *unusual_dev;
1077 	struct us_data *us;
1078 	int result;
1079 	int size;
1080 
1081 	/* If uas is enabled and this device can do uas then ignore it. */
1082 #if IS_ENABLED(CONFIG_USB_UAS)
1083 	if (uas_use_uas_driver(intf, id))
1084 		return -ENXIO;
1085 #endif
1086 
1087 	/*
1088 	 * If the device isn't standard (is handled by a subdriver
1089 	 * module) then don't accept it.
1090 	 */
1091 	if (usb_usual_ignore_device(intf))
1092 		return -ENXIO;
1093 
1094 	/*
1095 	 * Call the general probe procedures.
1096 	 *
1097 	 * The unusual_dev_list array is parallel to the usb_storage_usb_ids
1098 	 * table, so we use the index of the id entry to find the
1099 	 * corresponding unusual_devs entry.
1100 	 */
1101 
1102 	size = ARRAY_SIZE(us_unusual_dev_list);
1103 	if (id >= usb_storage_usb_ids && id < usb_storage_usb_ids + size) {
1104 		unusual_dev = (id - usb_storage_usb_ids) + us_unusual_dev_list;
1105 	} else {
1106 		unusual_dev = &for_dynamic_ids;
1107 
1108 		dev_dbg(&intf->dev, "Use Bulk-Only transport with the Transparent SCSI protocol for dynamic id: 0x%04x 0x%04x\n",
1109 			id->idVendor, id->idProduct);
1110 	}
1111 
1112 	result = usb_stor_probe1(&us, intf, id, unusual_dev);
1113 	if (result)
1114 		return result;
1115 
1116 	/* No special transport or protocol settings in the main module */
1117 
1118 	result = usb_stor_probe2(us);
1119 	return result;
1120 }
1121 
1122 static struct usb_driver usb_storage_driver = {
1123 	.name =		"usb-storage",
1124 	.probe =	storage_probe,
1125 	.disconnect =	usb_stor_disconnect,
1126 	.suspend =	usb_stor_suspend,
1127 	.resume =	usb_stor_resume,
1128 	.reset_resume =	usb_stor_reset_resume,
1129 	.pre_reset =	usb_stor_pre_reset,
1130 	.post_reset =	usb_stor_post_reset,
1131 	.id_table =	usb_storage_usb_ids,
1132 	.supports_autosuspend = 1,
1133 	.soft_unbind =	1,
1134 };
1135 
1136 module_usb_driver(usb_storage_driver);
1137