xref: /linux/drivers/scsi/scsi_sysfs.c (revision 90e0d94d369d342e735a75174439482119b6c393)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * scsi_sysfs.c
4  *
5  * SCSI sysfs interface routines.
6  *
7  * Created to pull SCSI mid layer sysfs routines into one file.
8  */
9 
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/init.h>
13 #include <linux/blkdev.h>
14 #include <linux/device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/bsg.h>
17 
18 #include <scsi/scsi.h>
19 #include <scsi/scsi_device.h>
20 #include <scsi/scsi_host.h>
21 #include <scsi/scsi_tcq.h>
22 #include <scsi/scsi_dh.h>
23 #include <scsi/scsi_transport.h>
24 #include <scsi/scsi_driver.h>
25 #include <scsi/scsi_devinfo.h>
26 
27 #include "scsi_priv.h"
28 #include "scsi_logging.h"
29 
30 static struct device_type scsi_dev_type;
31 
32 static const struct {
33 	enum scsi_device_state	value;
34 	char			*name;
35 } sdev_states[] = {
36 	{ SDEV_CREATED, "created" },
37 	{ SDEV_RUNNING, "running" },
38 	{ SDEV_CANCEL, "cancel" },
39 	{ SDEV_DEL, "deleted" },
40 	{ SDEV_QUIESCE, "quiesce" },
41 	{ SDEV_OFFLINE,	"offline" },
42 	{ SDEV_TRANSPORT_OFFLINE, "transport-offline" },
43 	{ SDEV_BLOCK,	"blocked" },
44 	{ SDEV_CREATED_BLOCK, "created-blocked" },
45 };
46 
47 const char *scsi_device_state_name(enum scsi_device_state state)
48 {
49 	int i;
50 	char *name = NULL;
51 
52 	for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
53 		if (sdev_states[i].value == state) {
54 			name = sdev_states[i].name;
55 			break;
56 		}
57 	}
58 	return name;
59 }
60 
61 static const struct {
62 	enum scsi_host_state	value;
63 	char			*name;
64 } shost_states[] = {
65 	{ SHOST_CREATED, "created" },
66 	{ SHOST_RUNNING, "running" },
67 	{ SHOST_CANCEL, "cancel" },
68 	{ SHOST_DEL, "deleted" },
69 	{ SHOST_RECOVERY, "recovery" },
70 	{ SHOST_CANCEL_RECOVERY, "cancel/recovery" },
71 	{ SHOST_DEL_RECOVERY, "deleted/recovery", },
72 };
73 const char *scsi_host_state_name(enum scsi_host_state state)
74 {
75 	int i;
76 	char *name = NULL;
77 
78 	for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
79 		if (shost_states[i].value == state) {
80 			name = shost_states[i].name;
81 			break;
82 		}
83 	}
84 	return name;
85 }
86 
87 #ifdef CONFIG_SCSI_DH
88 static const struct {
89 	unsigned char	value;
90 	char		*name;
91 } sdev_access_states[] = {
92 	{ SCSI_ACCESS_STATE_OPTIMAL, "active/optimized" },
93 	{ SCSI_ACCESS_STATE_ACTIVE, "active/non-optimized" },
94 	{ SCSI_ACCESS_STATE_STANDBY, "standby" },
95 	{ SCSI_ACCESS_STATE_UNAVAILABLE, "unavailable" },
96 	{ SCSI_ACCESS_STATE_LBA, "lba-dependent" },
97 	{ SCSI_ACCESS_STATE_OFFLINE, "offline" },
98 	{ SCSI_ACCESS_STATE_TRANSITIONING, "transitioning" },
99 };
100 
101 static const char *scsi_access_state_name(unsigned char state)
102 {
103 	int i;
104 	char *name = NULL;
105 
106 	for (i = 0; i < ARRAY_SIZE(sdev_access_states); i++) {
107 		if (sdev_access_states[i].value == state) {
108 			name = sdev_access_states[i].name;
109 			break;
110 		}
111 	}
112 	return name;
113 }
114 #endif
115 
116 static int check_set(unsigned long long *val, char *src)
117 {
118 	char *last;
119 
120 	if (strcmp(src, "-") == 0) {
121 		*val = SCAN_WILD_CARD;
122 	} else {
123 		/*
124 		 * Doesn't check for int overflow
125 		 */
126 		*val = simple_strtoull(src, &last, 0);
127 		if (*last != '\0')
128 			return 1;
129 	}
130 	return 0;
131 }
132 
133 static int scsi_scan(struct Scsi_Host *shost, const char *str)
134 {
135 	char s1[15], s2[15], s3[17], junk;
136 	unsigned long long channel, id, lun;
137 	int res;
138 
139 	res = sscanf(str, "%10s %10s %16s %c", s1, s2, s3, &junk);
140 	if (res != 3)
141 		return -EINVAL;
142 	if (check_set(&channel, s1))
143 		return -EINVAL;
144 	if (check_set(&id, s2))
145 		return -EINVAL;
146 	if (check_set(&lun, s3))
147 		return -EINVAL;
148 	if (shost->transportt->user_scan)
149 		res = shost->transportt->user_scan(shost, channel, id, lun);
150 	else
151 		res = scsi_scan_host_selected(shost, channel, id, lun,
152 					      SCSI_SCAN_MANUAL);
153 	return res;
154 }
155 
156 /*
157  * shost_show_function: macro to create an attr function that can be used to
158  * show a non-bit field.
159  */
160 #define shost_show_function(name, field, format_string)			\
161 static ssize_t								\
162 show_##name (struct device *dev, struct device_attribute *attr, 	\
163 	     char *buf)							\
164 {									\
165 	struct Scsi_Host *shost = class_to_shost(dev);			\
166 	return snprintf (buf, 20, format_string, shost->field);		\
167 }
168 
169 /*
170  * shost_rd_attr: macro to create a function and attribute variable for a
171  * read only field.
172  */
173 #define shost_rd_attr2(name, field, format_string)			\
174 	shost_show_function(name, field, format_string)			\
175 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
176 
177 #define shost_rd_attr(field, format_string) \
178 shost_rd_attr2(field, field, format_string)
179 
180 /*
181  * Create the actual show/store functions and data structures.
182  */
183 
184 static ssize_t
185 store_scan(struct device *dev, struct device_attribute *attr,
186 	   const char *buf, size_t count)
187 {
188 	struct Scsi_Host *shost = class_to_shost(dev);
189 	int res;
190 
191 	res = scsi_scan(shost, buf);
192 	if (res == 0)
193 		res = count;
194 	return res;
195 };
196 static DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
197 
198 static ssize_t
199 store_shost_state(struct device *dev, struct device_attribute *attr,
200 		  const char *buf, size_t count)
201 {
202 	int i;
203 	struct Scsi_Host *shost = class_to_shost(dev);
204 	enum scsi_host_state state = 0;
205 
206 	for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
207 		const int len = strlen(shost_states[i].name);
208 		if (strncmp(shost_states[i].name, buf, len) == 0 &&
209 		   buf[len] == '\n') {
210 			state = shost_states[i].value;
211 			break;
212 		}
213 	}
214 	if (!state)
215 		return -EINVAL;
216 
217 	if (scsi_host_set_state(shost, state))
218 		return -EINVAL;
219 	return count;
220 }
221 
222 static ssize_t
223 show_shost_state(struct device *dev, struct device_attribute *attr, char *buf)
224 {
225 	struct Scsi_Host *shost = class_to_shost(dev);
226 	const char *name = scsi_host_state_name(shost->shost_state);
227 
228 	if (!name)
229 		return -EINVAL;
230 
231 	return snprintf(buf, 20, "%s\n", name);
232 }
233 
234 /* DEVICE_ATTR(state) clashes with dev_attr_state for sdev */
235 static struct device_attribute dev_attr_hstate =
236 	__ATTR(state, S_IRUGO | S_IWUSR, show_shost_state, store_shost_state);
237 
238 static ssize_t
239 show_shost_mode(unsigned int mode, char *buf)
240 {
241 	ssize_t len = 0;
242 
243 	if (mode & MODE_INITIATOR)
244 		len = sprintf(buf, "%s", "Initiator");
245 
246 	if (mode & MODE_TARGET)
247 		len += sprintf(buf + len, "%s%s", len ? ", " : "", "Target");
248 
249 	len += sprintf(buf + len, "\n");
250 
251 	return len;
252 }
253 
254 static ssize_t
255 show_shost_supported_mode(struct device *dev, struct device_attribute *attr,
256 			  char *buf)
257 {
258 	struct Scsi_Host *shost = class_to_shost(dev);
259 	unsigned int supported_mode = shost->hostt->supported_mode;
260 
261 	if (supported_mode == MODE_UNKNOWN)
262 		/* by default this should be initiator */
263 		supported_mode = MODE_INITIATOR;
264 
265 	return show_shost_mode(supported_mode, buf);
266 }
267 
268 static DEVICE_ATTR(supported_mode, S_IRUGO | S_IWUSR, show_shost_supported_mode, NULL);
269 
270 static ssize_t
271 show_shost_active_mode(struct device *dev,
272 		       struct device_attribute *attr, char *buf)
273 {
274 	struct Scsi_Host *shost = class_to_shost(dev);
275 
276 	if (shost->active_mode == MODE_UNKNOWN)
277 		return snprintf(buf, 20, "unknown\n");
278 	else
279 		return show_shost_mode(shost->active_mode, buf);
280 }
281 
282 static DEVICE_ATTR(active_mode, S_IRUGO | S_IWUSR, show_shost_active_mode, NULL);
283 
284 static int check_reset_type(const char *str)
285 {
286 	if (sysfs_streq(str, "adapter"))
287 		return SCSI_ADAPTER_RESET;
288 	else if (sysfs_streq(str, "firmware"))
289 		return SCSI_FIRMWARE_RESET;
290 	else
291 		return 0;
292 }
293 
294 static ssize_t
295 store_host_reset(struct device *dev, struct device_attribute *attr,
296 		const char *buf, size_t count)
297 {
298 	struct Scsi_Host *shost = class_to_shost(dev);
299 	struct scsi_host_template *sht = shost->hostt;
300 	int ret = -EINVAL;
301 	int type;
302 
303 	type = check_reset_type(buf);
304 	if (!type)
305 		goto exit_store_host_reset;
306 
307 	if (sht->host_reset)
308 		ret = sht->host_reset(shost, type);
309 	else
310 		ret = -EOPNOTSUPP;
311 
312 exit_store_host_reset:
313 	if (ret == 0)
314 		ret = count;
315 	return ret;
316 }
317 
318 static DEVICE_ATTR(host_reset, S_IWUSR, NULL, store_host_reset);
319 
320 static ssize_t
321 show_shost_eh_deadline(struct device *dev,
322 		      struct device_attribute *attr, char *buf)
323 {
324 	struct Scsi_Host *shost = class_to_shost(dev);
325 
326 	if (shost->eh_deadline == -1)
327 		return snprintf(buf, strlen("off") + 2, "off\n");
328 	return sprintf(buf, "%u\n", shost->eh_deadline / HZ);
329 }
330 
331 static ssize_t
332 store_shost_eh_deadline(struct device *dev, struct device_attribute *attr,
333 		const char *buf, size_t count)
334 {
335 	struct Scsi_Host *shost = class_to_shost(dev);
336 	int ret = -EINVAL;
337 	unsigned long deadline, flags;
338 
339 	if (shost->transportt &&
340 	    (shost->transportt->eh_strategy_handler ||
341 	     !shost->hostt->eh_host_reset_handler))
342 		return ret;
343 
344 	if (!strncmp(buf, "off", strlen("off")))
345 		deadline = -1;
346 	else {
347 		ret = kstrtoul(buf, 10, &deadline);
348 		if (ret)
349 			return ret;
350 		if (deadline * HZ > UINT_MAX)
351 			return -EINVAL;
352 	}
353 
354 	spin_lock_irqsave(shost->host_lock, flags);
355 	if (scsi_host_in_recovery(shost))
356 		ret = -EBUSY;
357 	else {
358 		if (deadline == -1)
359 			shost->eh_deadline = -1;
360 		else
361 			shost->eh_deadline = deadline * HZ;
362 
363 		ret = count;
364 	}
365 	spin_unlock_irqrestore(shost->host_lock, flags);
366 
367 	return ret;
368 }
369 
370 static DEVICE_ATTR(eh_deadline, S_IRUGO | S_IWUSR, show_shost_eh_deadline, store_shost_eh_deadline);
371 
372 shost_rd_attr(unique_id, "%u\n");
373 shost_rd_attr(cmd_per_lun, "%hd\n");
374 shost_rd_attr(can_queue, "%d\n");
375 shost_rd_attr(sg_tablesize, "%hu\n");
376 shost_rd_attr(sg_prot_tablesize, "%hu\n");
377 shost_rd_attr(prot_capabilities, "%u\n");
378 shost_rd_attr(prot_guard_type, "%hd\n");
379 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
380 
381 static ssize_t
382 show_host_busy(struct device *dev, struct device_attribute *attr, char *buf)
383 {
384 	struct Scsi_Host *shost = class_to_shost(dev);
385 	return snprintf(buf, 20, "%d\n", scsi_host_busy(shost));
386 }
387 static DEVICE_ATTR(host_busy, S_IRUGO, show_host_busy, NULL);
388 
389 static ssize_t
390 show_use_blk_mq(struct device *dev, struct device_attribute *attr, char *buf)
391 {
392 	return sprintf(buf, "1\n");
393 }
394 static DEVICE_ATTR(use_blk_mq, S_IRUGO, show_use_blk_mq, NULL);
395 
396 static ssize_t
397 show_nr_hw_queues(struct device *dev, struct device_attribute *attr, char *buf)
398 {
399 	struct Scsi_Host *shost = class_to_shost(dev);
400 	struct blk_mq_tag_set *tag_set = &shost->tag_set;
401 
402 	return snprintf(buf, 20, "%d\n", tag_set->nr_hw_queues);
403 }
404 static DEVICE_ATTR(nr_hw_queues, S_IRUGO, show_nr_hw_queues, NULL);
405 
406 static struct attribute *scsi_sysfs_shost_attrs[] = {
407 	&dev_attr_use_blk_mq.attr,
408 	&dev_attr_unique_id.attr,
409 	&dev_attr_host_busy.attr,
410 	&dev_attr_cmd_per_lun.attr,
411 	&dev_attr_can_queue.attr,
412 	&dev_attr_sg_tablesize.attr,
413 	&dev_attr_sg_prot_tablesize.attr,
414 	&dev_attr_proc_name.attr,
415 	&dev_attr_scan.attr,
416 	&dev_attr_hstate.attr,
417 	&dev_attr_supported_mode.attr,
418 	&dev_attr_active_mode.attr,
419 	&dev_attr_prot_capabilities.attr,
420 	&dev_attr_prot_guard_type.attr,
421 	&dev_attr_host_reset.attr,
422 	&dev_attr_eh_deadline.attr,
423 	&dev_attr_nr_hw_queues.attr,
424 	NULL
425 };
426 
427 static const struct attribute_group scsi_shost_attr_group = {
428 	.attrs =	scsi_sysfs_shost_attrs,
429 };
430 
431 const struct attribute_group *scsi_shost_groups[] = {
432 	&scsi_shost_attr_group,
433 	NULL
434 };
435 
436 static void scsi_device_cls_release(struct device *class_dev)
437 {
438 	struct scsi_device *sdev;
439 
440 	sdev = class_to_sdev(class_dev);
441 	put_device(&sdev->sdev_gendev);
442 }
443 
444 static void scsi_device_dev_release_usercontext(struct work_struct *work)
445 {
446 	struct scsi_device *sdev;
447 	struct device *parent;
448 	struct list_head *this, *tmp;
449 	struct scsi_vpd *vpd_pg80 = NULL, *vpd_pg83 = NULL;
450 	struct scsi_vpd *vpd_pg0 = NULL, *vpd_pg89 = NULL;
451 	struct scsi_vpd *vpd_pgb0 = NULL, *vpd_pgb1 = NULL, *vpd_pgb2 = NULL;
452 	unsigned long flags;
453 	struct module *mod;
454 
455 	sdev = container_of(work, struct scsi_device, ew.work);
456 
457 	mod = sdev->host->hostt->module;
458 
459 	scsi_dh_release_device(sdev);
460 
461 	parent = sdev->sdev_gendev.parent;
462 
463 	spin_lock_irqsave(sdev->host->host_lock, flags);
464 	list_del(&sdev->siblings);
465 	list_del(&sdev->same_target_siblings);
466 	list_del(&sdev->starved_entry);
467 	spin_unlock_irqrestore(sdev->host->host_lock, flags);
468 
469 	cancel_work_sync(&sdev->event_work);
470 
471 	list_for_each_safe(this, tmp, &sdev->event_list) {
472 		struct scsi_event *evt;
473 
474 		evt = list_entry(this, struct scsi_event, node);
475 		list_del(&evt->node);
476 		kfree(evt);
477 	}
478 
479 	blk_put_queue(sdev->request_queue);
480 	/* NULL queue means the device can't be used */
481 	sdev->request_queue = NULL;
482 
483 	sbitmap_free(&sdev->budget_map);
484 
485 	mutex_lock(&sdev->inquiry_mutex);
486 	vpd_pg0 = rcu_replace_pointer(sdev->vpd_pg0, vpd_pg0,
487 				       lockdep_is_held(&sdev->inquiry_mutex));
488 	vpd_pg80 = rcu_replace_pointer(sdev->vpd_pg80, vpd_pg80,
489 				       lockdep_is_held(&sdev->inquiry_mutex));
490 	vpd_pg83 = rcu_replace_pointer(sdev->vpd_pg83, vpd_pg83,
491 				       lockdep_is_held(&sdev->inquiry_mutex));
492 	vpd_pg89 = rcu_replace_pointer(sdev->vpd_pg89, vpd_pg89,
493 				       lockdep_is_held(&sdev->inquiry_mutex));
494 	vpd_pgb0 = rcu_replace_pointer(sdev->vpd_pgb0, vpd_pgb0,
495 				       lockdep_is_held(&sdev->inquiry_mutex));
496 	vpd_pgb1 = rcu_replace_pointer(sdev->vpd_pgb1, vpd_pgb1,
497 				       lockdep_is_held(&sdev->inquiry_mutex));
498 	vpd_pgb2 = rcu_replace_pointer(sdev->vpd_pgb2, vpd_pgb2,
499 				       lockdep_is_held(&sdev->inquiry_mutex));
500 	mutex_unlock(&sdev->inquiry_mutex);
501 
502 	if (vpd_pg0)
503 		kfree_rcu(vpd_pg0, rcu);
504 	if (vpd_pg83)
505 		kfree_rcu(vpd_pg83, rcu);
506 	if (vpd_pg80)
507 		kfree_rcu(vpd_pg80, rcu);
508 	if (vpd_pg89)
509 		kfree_rcu(vpd_pg89, rcu);
510 	if (vpd_pgb0)
511 		kfree_rcu(vpd_pgb0, rcu);
512 	if (vpd_pgb1)
513 		kfree_rcu(vpd_pgb1, rcu);
514 	if (vpd_pgb2)
515 		kfree_rcu(vpd_pgb2, rcu);
516 	kfree(sdev->inquiry);
517 	kfree(sdev);
518 
519 	if (parent)
520 		put_device(parent);
521 	module_put(mod);
522 }
523 
524 static void scsi_device_dev_release(struct device *dev)
525 {
526 	struct scsi_device *sdp = to_scsi_device(dev);
527 
528 	/* Set module pointer as NULL in case of module unloading */
529 	if (!try_module_get(sdp->host->hostt->module))
530 		sdp->host->hostt->module = NULL;
531 
532 	execute_in_process_context(scsi_device_dev_release_usercontext,
533 				   &sdp->ew);
534 }
535 
536 static struct class sdev_class = {
537 	.name		= "scsi_device",
538 	.dev_release	= scsi_device_cls_release,
539 };
540 
541 /* all probing is done in the individual ->probe routines */
542 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
543 {
544 	struct scsi_device *sdp;
545 
546 	if (dev->type != &scsi_dev_type)
547 		return 0;
548 
549 	sdp = to_scsi_device(dev);
550 	if (sdp->no_uld_attach)
551 		return 0;
552 	return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
553 }
554 
555 static int scsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
556 {
557 	struct scsi_device *sdev;
558 
559 	if (dev->type != &scsi_dev_type)
560 		return 0;
561 
562 	sdev = to_scsi_device(dev);
563 
564 	add_uevent_var(env, "MODALIAS=" SCSI_DEVICE_MODALIAS_FMT, sdev->type);
565 	return 0;
566 }
567 
568 struct bus_type scsi_bus_type = {
569         .name		= "scsi",
570         .match		= scsi_bus_match,
571 	.uevent		= scsi_bus_uevent,
572 #ifdef CONFIG_PM
573 	.pm		= &scsi_bus_pm_ops,
574 #endif
575 };
576 
577 int scsi_sysfs_register(void)
578 {
579 	int error;
580 
581 	error = bus_register(&scsi_bus_type);
582 	if (!error) {
583 		error = class_register(&sdev_class);
584 		if (error)
585 			bus_unregister(&scsi_bus_type);
586 	}
587 
588 	return error;
589 }
590 
591 void scsi_sysfs_unregister(void)
592 {
593 	class_unregister(&sdev_class);
594 	bus_unregister(&scsi_bus_type);
595 }
596 
597 /*
598  * sdev_show_function: macro to create an attr function that can be used to
599  * show a non-bit field.
600  */
601 #define sdev_show_function(field, format_string)				\
602 static ssize_t								\
603 sdev_show_##field (struct device *dev, struct device_attribute *attr,	\
604 		   char *buf)						\
605 {									\
606 	struct scsi_device *sdev;					\
607 	sdev = to_scsi_device(dev);					\
608 	return snprintf (buf, 20, format_string, sdev->field);		\
609 }									\
610 
611 /*
612  * sdev_rd_attr: macro to create a function and attribute variable for a
613  * read only field.
614  */
615 #define sdev_rd_attr(field, format_string)				\
616 	sdev_show_function(field, format_string)			\
617 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
618 
619 
620 /*
621  * sdev_rw_attr: create a function and attribute variable for a
622  * read/write field.
623  */
624 #define sdev_rw_attr(field, format_string)				\
625 	sdev_show_function(field, format_string)				\
626 									\
627 static ssize_t								\
628 sdev_store_##field (struct device *dev, struct device_attribute *attr,	\
629 		    const char *buf, size_t count)			\
630 {									\
631 	struct scsi_device *sdev;					\
632 	sdev = to_scsi_device(dev);					\
633 	sscanf (buf, format_string, &sdev->field);			\
634 	return count;							\
635 }									\
636 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
637 
638 /* Currently we don't export bit fields, but we might in future,
639  * so leave this code in */
640 #if 0
641 /*
642  * sdev_rd_attr: create a function and attribute variable for a
643  * read/write bit field.
644  */
645 #define sdev_rw_attr_bit(field)						\
646 	sdev_show_function(field, "%d\n")					\
647 									\
648 static ssize_t								\
649 sdev_store_##field (struct device *dev, struct device_attribute *attr,	\
650 		    const char *buf, size_t count)			\
651 {									\
652 	int ret;							\
653 	struct scsi_device *sdev;					\
654 	ret = scsi_sdev_check_buf_bit(buf);				\
655 	if (ret >= 0)	{						\
656 		sdev = to_scsi_device(dev);				\
657 		sdev->field = ret;					\
658 		ret = count;						\
659 	}								\
660 	return ret;							\
661 }									\
662 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
663 
664 /*
665  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
666  * else return -EINVAL.
667  */
668 static int scsi_sdev_check_buf_bit(const char *buf)
669 {
670 	if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
671 		if (buf[0] == '1')
672 			return 1;
673 		else if (buf[0] == '0')
674 			return 0;
675 		else
676 			return -EINVAL;
677 	} else
678 		return -EINVAL;
679 }
680 #endif
681 /*
682  * Create the actual show/store functions and data structures.
683  */
684 sdev_rd_attr (type, "%d\n");
685 sdev_rd_attr (scsi_level, "%d\n");
686 sdev_rd_attr (vendor, "%.8s\n");
687 sdev_rd_attr (model, "%.16s\n");
688 sdev_rd_attr (rev, "%.4s\n");
689 
690 static ssize_t
691 sdev_show_device_busy(struct device *dev, struct device_attribute *attr,
692 		char *buf)
693 {
694 	struct scsi_device *sdev = to_scsi_device(dev);
695 	return snprintf(buf, 20, "%d\n", scsi_device_busy(sdev));
696 }
697 static DEVICE_ATTR(device_busy, S_IRUGO, sdev_show_device_busy, NULL);
698 
699 static ssize_t
700 sdev_show_device_blocked(struct device *dev, struct device_attribute *attr,
701 		char *buf)
702 {
703 	struct scsi_device *sdev = to_scsi_device(dev);
704 	return snprintf(buf, 20, "%d\n", atomic_read(&sdev->device_blocked));
705 }
706 static DEVICE_ATTR(device_blocked, S_IRUGO, sdev_show_device_blocked, NULL);
707 
708 /*
709  * TODO: can we make these symlinks to the block layer ones?
710  */
711 static ssize_t
712 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
713 {
714 	struct scsi_device *sdev;
715 	sdev = to_scsi_device(dev);
716 	return snprintf(buf, 20, "%d\n", sdev->request_queue->rq_timeout / HZ);
717 }
718 
719 static ssize_t
720 sdev_store_timeout (struct device *dev, struct device_attribute *attr,
721 		    const char *buf, size_t count)
722 {
723 	struct scsi_device *sdev;
724 	int timeout;
725 	sdev = to_scsi_device(dev);
726 	sscanf (buf, "%d\n", &timeout);
727 	blk_queue_rq_timeout(sdev->request_queue, timeout * HZ);
728 	return count;
729 }
730 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
731 
732 static ssize_t
733 sdev_show_eh_timeout(struct device *dev, struct device_attribute *attr, char *buf)
734 {
735 	struct scsi_device *sdev;
736 	sdev = to_scsi_device(dev);
737 	return snprintf(buf, 20, "%u\n", sdev->eh_timeout / HZ);
738 }
739 
740 static ssize_t
741 sdev_store_eh_timeout(struct device *dev, struct device_attribute *attr,
742 		    const char *buf, size_t count)
743 {
744 	struct scsi_device *sdev;
745 	unsigned int eh_timeout;
746 	int err;
747 
748 	if (!capable(CAP_SYS_ADMIN))
749 		return -EACCES;
750 
751 	sdev = to_scsi_device(dev);
752 	err = kstrtouint(buf, 10, &eh_timeout);
753 	if (err)
754 		return err;
755 	sdev->eh_timeout = eh_timeout * HZ;
756 
757 	return count;
758 }
759 static DEVICE_ATTR(eh_timeout, S_IRUGO | S_IWUSR, sdev_show_eh_timeout, sdev_store_eh_timeout);
760 
761 static ssize_t
762 store_rescan_field (struct device *dev, struct device_attribute *attr,
763 		    const char *buf, size_t count)
764 {
765 	scsi_rescan_device(dev);
766 	return count;
767 }
768 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
769 
770 static ssize_t
771 sdev_store_delete(struct device *dev, struct device_attribute *attr,
772 		  const char *buf, size_t count)
773 {
774 	struct kernfs_node *kn;
775 	struct scsi_device *sdev = to_scsi_device(dev);
776 
777 	/*
778 	 * We need to try to get module, avoiding the module been removed
779 	 * during delete.
780 	 */
781 	if (scsi_device_get(sdev))
782 		return -ENODEV;
783 
784 	kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
785 	WARN_ON_ONCE(!kn);
786 	/*
787 	 * Concurrent writes into the "delete" sysfs attribute may trigger
788 	 * concurrent calls to device_remove_file() and scsi_remove_device().
789 	 * device_remove_file() handles concurrent removal calls by
790 	 * serializing these and by ignoring the second and later removal
791 	 * attempts.  Concurrent calls of scsi_remove_device() are
792 	 * serialized. The second and later calls of scsi_remove_device() are
793 	 * ignored because the first call of that function changes the device
794 	 * state into SDEV_DEL.
795 	 */
796 	device_remove_file(dev, attr);
797 	scsi_remove_device(sdev);
798 	if (kn)
799 		sysfs_unbreak_active_protection(kn);
800 	scsi_device_put(sdev);
801 	return count;
802 };
803 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
804 
805 static ssize_t
806 store_state_field(struct device *dev, struct device_attribute *attr,
807 		  const char *buf, size_t count)
808 {
809 	int i, ret;
810 	struct scsi_device *sdev = to_scsi_device(dev);
811 	enum scsi_device_state state = 0;
812 	bool rescan_dev = false;
813 
814 	for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
815 		const int len = strlen(sdev_states[i].name);
816 		if (strncmp(sdev_states[i].name, buf, len) == 0 &&
817 		   buf[len] == '\n') {
818 			state = sdev_states[i].value;
819 			break;
820 		}
821 	}
822 	switch (state) {
823 	case SDEV_RUNNING:
824 	case SDEV_OFFLINE:
825 		break;
826 	default:
827 		return -EINVAL;
828 	}
829 
830 	mutex_lock(&sdev->state_mutex);
831 	if (sdev->sdev_state == SDEV_RUNNING && state == SDEV_RUNNING) {
832 		ret = 0;
833 	} else {
834 		ret = scsi_device_set_state(sdev, state);
835 		if (ret == 0 && state == SDEV_RUNNING)
836 			rescan_dev = true;
837 	}
838 	mutex_unlock(&sdev->state_mutex);
839 
840 	if (rescan_dev) {
841 		/*
842 		 * If the device state changes to SDEV_RUNNING, we need to
843 		 * run the queue to avoid I/O hang, and rescan the device
844 		 * to revalidate it. Running the queue first is necessary
845 		 * because another thread may be waiting inside
846 		 * blk_mq_freeze_queue_wait() and because that call may be
847 		 * waiting for pending I/O to finish.
848 		 */
849 		blk_mq_run_hw_queues(sdev->request_queue, true);
850 		scsi_rescan_device(dev);
851 	}
852 
853 	return ret == 0 ? count : -EINVAL;
854 }
855 
856 static ssize_t
857 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
858 {
859 	struct scsi_device *sdev = to_scsi_device(dev);
860 	const char *name = scsi_device_state_name(sdev->sdev_state);
861 
862 	if (!name)
863 		return -EINVAL;
864 
865 	return snprintf(buf, 20, "%s\n", name);
866 }
867 
868 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
869 
870 static ssize_t
871 show_queue_type_field(struct device *dev, struct device_attribute *attr,
872 		      char *buf)
873 {
874 	struct scsi_device *sdev = to_scsi_device(dev);
875 	const char *name = "none";
876 
877 	if (sdev->simple_tags)
878 		name = "simple";
879 
880 	return snprintf(buf, 20, "%s\n", name);
881 }
882 
883 static ssize_t
884 store_queue_type_field(struct device *dev, struct device_attribute *attr,
885 		       const char *buf, size_t count)
886 {
887 	struct scsi_device *sdev = to_scsi_device(dev);
888 
889 	if (!sdev->tagged_supported)
890 		return -EINVAL;
891 
892 	sdev_printk(KERN_INFO, sdev,
893 		    "ignoring write to deprecated queue_type attribute");
894 	return count;
895 }
896 
897 static DEVICE_ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
898 		   store_queue_type_field);
899 
900 #define sdev_vpd_pg_attr(_page)						\
901 static ssize_t							\
902 show_vpd_##_page(struct file *filp, struct kobject *kobj,	\
903 		 struct bin_attribute *bin_attr,			\
904 		 char *buf, loff_t off, size_t count)			\
905 {									\
906 	struct device *dev = kobj_to_dev(kobj);				\
907 	struct scsi_device *sdev = to_scsi_device(dev);			\
908 	struct scsi_vpd *vpd_page;					\
909 	int ret = -EINVAL;						\
910 									\
911 	rcu_read_lock();						\
912 	vpd_page = rcu_dereference(sdev->vpd_##_page);			\
913 	if (vpd_page)							\
914 		ret = memory_read_from_buffer(buf, count, &off,		\
915 				vpd_page->data, vpd_page->len);		\
916 	rcu_read_unlock();						\
917 	return ret;							\
918 }									\
919 static struct bin_attribute dev_attr_vpd_##_page = {		\
920 	.attr =	{.name = __stringify(vpd_##_page), .mode = S_IRUGO },	\
921 	.size = 0,							\
922 	.read = show_vpd_##_page,					\
923 };
924 
925 sdev_vpd_pg_attr(pg83);
926 sdev_vpd_pg_attr(pg80);
927 sdev_vpd_pg_attr(pg89);
928 sdev_vpd_pg_attr(pgb0);
929 sdev_vpd_pg_attr(pgb1);
930 sdev_vpd_pg_attr(pgb2);
931 sdev_vpd_pg_attr(pg0);
932 
933 static ssize_t show_inquiry(struct file *filep, struct kobject *kobj,
934 			    struct bin_attribute *bin_attr,
935 			    char *buf, loff_t off, size_t count)
936 {
937 	struct device *dev = kobj_to_dev(kobj);
938 	struct scsi_device *sdev = to_scsi_device(dev);
939 
940 	if (!sdev->inquiry)
941 		return -EINVAL;
942 
943 	return memory_read_from_buffer(buf, count, &off, sdev->inquiry,
944 				       sdev->inquiry_len);
945 }
946 
947 static struct bin_attribute dev_attr_inquiry = {
948 	.attr = {
949 		.name = "inquiry",
950 		.mode = S_IRUGO,
951 	},
952 	.size = 0,
953 	.read = show_inquiry,
954 };
955 
956 static ssize_t
957 show_iostat_counterbits(struct device *dev, struct device_attribute *attr,
958 			char *buf)
959 {
960 	return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
961 }
962 
963 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
964 
965 #define show_sdev_iostat(field)						\
966 static ssize_t								\
967 show_iostat_##field(struct device *dev, struct device_attribute *attr,	\
968 		    char *buf)						\
969 {									\
970 	struct scsi_device *sdev = to_scsi_device(dev);			\
971 	unsigned long long count = atomic_read(&sdev->field);		\
972 	return snprintf(buf, 20, "0x%llx\n", count);			\
973 }									\
974 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
975 
976 show_sdev_iostat(iorequest_cnt);
977 show_sdev_iostat(iodone_cnt);
978 show_sdev_iostat(ioerr_cnt);
979 show_sdev_iostat(iotmo_cnt);
980 
981 static ssize_t
982 sdev_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
983 {
984 	struct scsi_device *sdev;
985 	sdev = to_scsi_device(dev);
986 	return snprintf (buf, 20, SCSI_DEVICE_MODALIAS_FMT "\n", sdev->type);
987 }
988 static DEVICE_ATTR(modalias, S_IRUGO, sdev_show_modalias, NULL);
989 
990 #define DECLARE_EVT_SHOW(name, Cap_name)				\
991 static ssize_t								\
992 sdev_show_evt_##name(struct device *dev, struct device_attribute *attr,	\
993 		     char *buf)						\
994 {									\
995 	struct scsi_device *sdev = to_scsi_device(dev);			\
996 	int val = test_bit(SDEV_EVT_##Cap_name, sdev->supported_events);\
997 	return snprintf(buf, 20, "%d\n", val);				\
998 }
999 
1000 #define DECLARE_EVT_STORE(name, Cap_name)				\
1001 static ssize_t								\
1002 sdev_store_evt_##name(struct device *dev, struct device_attribute *attr,\
1003 		      const char *buf, size_t count)			\
1004 {									\
1005 	struct scsi_device *sdev = to_scsi_device(dev);			\
1006 	int val = simple_strtoul(buf, NULL, 0);				\
1007 	if (val == 0)							\
1008 		clear_bit(SDEV_EVT_##Cap_name, sdev->supported_events);	\
1009 	else if (val == 1)						\
1010 		set_bit(SDEV_EVT_##Cap_name, sdev->supported_events);	\
1011 	else								\
1012 		return -EINVAL;						\
1013 	return count;							\
1014 }
1015 
1016 #define DECLARE_EVT(name, Cap_name)					\
1017 	DECLARE_EVT_SHOW(name, Cap_name)				\
1018 	DECLARE_EVT_STORE(name, Cap_name)				\
1019 	static DEVICE_ATTR(evt_##name, S_IRUGO, sdev_show_evt_##name,	\
1020 			   sdev_store_evt_##name);
1021 #define REF_EVT(name) &dev_attr_evt_##name.attr
1022 
1023 DECLARE_EVT(media_change, MEDIA_CHANGE)
1024 DECLARE_EVT(inquiry_change_reported, INQUIRY_CHANGE_REPORTED)
1025 DECLARE_EVT(capacity_change_reported, CAPACITY_CHANGE_REPORTED)
1026 DECLARE_EVT(soft_threshold_reached, SOFT_THRESHOLD_REACHED_REPORTED)
1027 DECLARE_EVT(mode_parameter_change_reported, MODE_PARAMETER_CHANGE_REPORTED)
1028 DECLARE_EVT(lun_change_reported, LUN_CHANGE_REPORTED)
1029 
1030 static ssize_t
1031 sdev_store_queue_depth(struct device *dev, struct device_attribute *attr,
1032 		       const char *buf, size_t count)
1033 {
1034 	int depth, retval;
1035 	struct scsi_device *sdev = to_scsi_device(dev);
1036 	struct scsi_host_template *sht = sdev->host->hostt;
1037 
1038 	if (!sht->change_queue_depth)
1039 		return -EINVAL;
1040 
1041 	depth = simple_strtoul(buf, NULL, 0);
1042 
1043 	if (depth < 1 || depth > sdev->host->can_queue)
1044 		return -EINVAL;
1045 
1046 	retval = sht->change_queue_depth(sdev, depth);
1047 	if (retval < 0)
1048 		return retval;
1049 
1050 	sdev->max_queue_depth = sdev->queue_depth;
1051 
1052 	return count;
1053 }
1054 sdev_show_function(queue_depth, "%d\n");
1055 
1056 static DEVICE_ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
1057 		   sdev_store_queue_depth);
1058 
1059 static ssize_t
1060 sdev_show_wwid(struct device *dev, struct device_attribute *attr,
1061 		    char *buf)
1062 {
1063 	struct scsi_device *sdev = to_scsi_device(dev);
1064 	ssize_t count;
1065 
1066 	count = scsi_vpd_lun_id(sdev, buf, PAGE_SIZE);
1067 	if (count > 0) {
1068 		buf[count] = '\n';
1069 		count++;
1070 	}
1071 	return count;
1072 }
1073 static DEVICE_ATTR(wwid, S_IRUGO, sdev_show_wwid, NULL);
1074 
1075 #define BLIST_FLAG_NAME(name)					\
1076 	[const_ilog2((__force __u64)BLIST_##name)] = #name
1077 static const char *const sdev_bflags_name[] = {
1078 #include "scsi_devinfo_tbl.c"
1079 };
1080 #undef BLIST_FLAG_NAME
1081 
1082 static ssize_t
1083 sdev_show_blacklist(struct device *dev, struct device_attribute *attr,
1084 		    char *buf)
1085 {
1086 	struct scsi_device *sdev = to_scsi_device(dev);
1087 	int i;
1088 	ssize_t len = 0;
1089 
1090 	for (i = 0; i < sizeof(sdev->sdev_bflags) * BITS_PER_BYTE; i++) {
1091 		const char *name = NULL;
1092 
1093 		if (!(sdev->sdev_bflags & (__force blist_flags_t)BIT(i)))
1094 			continue;
1095 		if (i < ARRAY_SIZE(sdev_bflags_name) && sdev_bflags_name[i])
1096 			name = sdev_bflags_name[i];
1097 
1098 		if (name)
1099 			len += scnprintf(buf + len, PAGE_SIZE - len,
1100 					 "%s%s", len ? " " : "", name);
1101 		else
1102 			len += scnprintf(buf + len, PAGE_SIZE - len,
1103 					 "%sINVALID_BIT(%d)", len ? " " : "", i);
1104 	}
1105 	if (len)
1106 		len += scnprintf(buf + len, PAGE_SIZE - len, "\n");
1107 	return len;
1108 }
1109 static DEVICE_ATTR(blacklist, S_IRUGO, sdev_show_blacklist, NULL);
1110 
1111 #ifdef CONFIG_SCSI_DH
1112 static ssize_t
1113 sdev_show_dh_state(struct device *dev, struct device_attribute *attr,
1114 		   char *buf)
1115 {
1116 	struct scsi_device *sdev = to_scsi_device(dev);
1117 
1118 	if (!sdev->handler)
1119 		return snprintf(buf, 20, "detached\n");
1120 
1121 	return snprintf(buf, 20, "%s\n", sdev->handler->name);
1122 }
1123 
1124 static ssize_t
1125 sdev_store_dh_state(struct device *dev, struct device_attribute *attr,
1126 		    const char *buf, size_t count)
1127 {
1128 	struct scsi_device *sdev = to_scsi_device(dev);
1129 	int err = -EINVAL;
1130 
1131 	if (sdev->sdev_state == SDEV_CANCEL ||
1132 	    sdev->sdev_state == SDEV_DEL)
1133 		return -ENODEV;
1134 
1135 	if (!sdev->handler) {
1136 		/*
1137 		 * Attach to a device handler
1138 		 */
1139 		err = scsi_dh_attach(sdev->request_queue, buf);
1140 	} else if (!strncmp(buf, "activate", 8)) {
1141 		/*
1142 		 * Activate a device handler
1143 		 */
1144 		if (sdev->handler->activate)
1145 			err = sdev->handler->activate(sdev, NULL, NULL);
1146 		else
1147 			err = 0;
1148 	} else if (!strncmp(buf, "detach", 6)) {
1149 		/*
1150 		 * Detach from a device handler
1151 		 */
1152 		sdev_printk(KERN_WARNING, sdev,
1153 			    "can't detach handler %s.\n",
1154 			    sdev->handler->name);
1155 		err = -EINVAL;
1156 	}
1157 
1158 	return err < 0 ? err : count;
1159 }
1160 
1161 static DEVICE_ATTR(dh_state, S_IRUGO | S_IWUSR, sdev_show_dh_state,
1162 		   sdev_store_dh_state);
1163 
1164 static ssize_t
1165 sdev_show_access_state(struct device *dev,
1166 		       struct device_attribute *attr,
1167 		       char *buf)
1168 {
1169 	struct scsi_device *sdev = to_scsi_device(dev);
1170 	unsigned char access_state;
1171 	const char *access_state_name;
1172 
1173 	if (!sdev->handler)
1174 		return -EINVAL;
1175 
1176 	access_state = (sdev->access_state & SCSI_ACCESS_STATE_MASK);
1177 	access_state_name = scsi_access_state_name(access_state);
1178 
1179 	return sprintf(buf, "%s\n",
1180 		       access_state_name ? access_state_name : "unknown");
1181 }
1182 static DEVICE_ATTR(access_state, S_IRUGO, sdev_show_access_state, NULL);
1183 
1184 static ssize_t
1185 sdev_show_preferred_path(struct device *dev,
1186 			 struct device_attribute *attr,
1187 			 char *buf)
1188 {
1189 	struct scsi_device *sdev = to_scsi_device(dev);
1190 
1191 	if (!sdev->handler)
1192 		return -EINVAL;
1193 
1194 	if (sdev->access_state & SCSI_ACCESS_STATE_PREFERRED)
1195 		return sprintf(buf, "1\n");
1196 	else
1197 		return sprintf(buf, "0\n");
1198 }
1199 static DEVICE_ATTR(preferred_path, S_IRUGO, sdev_show_preferred_path, NULL);
1200 #endif
1201 
1202 static ssize_t
1203 sdev_show_queue_ramp_up_period(struct device *dev,
1204 			       struct device_attribute *attr,
1205 			       char *buf)
1206 {
1207 	struct scsi_device *sdev;
1208 	sdev = to_scsi_device(dev);
1209 	return snprintf(buf, 20, "%u\n",
1210 			jiffies_to_msecs(sdev->queue_ramp_up_period));
1211 }
1212 
1213 static ssize_t
1214 sdev_store_queue_ramp_up_period(struct device *dev,
1215 				struct device_attribute *attr,
1216 				const char *buf, size_t count)
1217 {
1218 	struct scsi_device *sdev = to_scsi_device(dev);
1219 	unsigned int period;
1220 
1221 	if (kstrtouint(buf, 10, &period))
1222 		return -EINVAL;
1223 
1224 	sdev->queue_ramp_up_period = msecs_to_jiffies(period);
1225 	return count;
1226 }
1227 
1228 static DEVICE_ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR,
1229 		   sdev_show_queue_ramp_up_period,
1230 		   sdev_store_queue_ramp_up_period);
1231 
1232 static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
1233 					 struct attribute *attr, int i)
1234 {
1235 	struct device *dev = kobj_to_dev(kobj);
1236 	struct scsi_device *sdev = to_scsi_device(dev);
1237 
1238 
1239 	if (attr == &dev_attr_queue_depth.attr &&
1240 	    !sdev->host->hostt->change_queue_depth)
1241 		return S_IRUGO;
1242 
1243 	if (attr == &dev_attr_queue_ramp_up_period.attr &&
1244 	    !sdev->host->hostt->change_queue_depth)
1245 		return 0;
1246 
1247 	return attr->mode;
1248 }
1249 
1250 static umode_t scsi_sdev_bin_attr_is_visible(struct kobject *kobj,
1251 					     struct bin_attribute *attr, int i)
1252 {
1253 	struct device *dev = kobj_to_dev(kobj);
1254 	struct scsi_device *sdev = to_scsi_device(dev);
1255 
1256 
1257 	if (attr == &dev_attr_vpd_pg0 && !sdev->vpd_pg0)
1258 		return 0;
1259 
1260 	if (attr == &dev_attr_vpd_pg80 && !sdev->vpd_pg80)
1261 		return 0;
1262 
1263 	if (attr == &dev_attr_vpd_pg83 && !sdev->vpd_pg83)
1264 		return 0;
1265 
1266 	if (attr == &dev_attr_vpd_pg89 && !sdev->vpd_pg89)
1267 		return 0;
1268 
1269 	if (attr == &dev_attr_vpd_pgb0 && !sdev->vpd_pgb0)
1270 		return 0;
1271 
1272 	if (attr == &dev_attr_vpd_pgb1 && !sdev->vpd_pgb1)
1273 		return 0;
1274 
1275 	if (attr == &dev_attr_vpd_pgb2 && !sdev->vpd_pgb2)
1276 		return 0;
1277 
1278 	return S_IRUGO;
1279 }
1280 
1281 /* Default template for device attributes.  May NOT be modified */
1282 static struct attribute *scsi_sdev_attrs[] = {
1283 	&dev_attr_device_blocked.attr,
1284 	&dev_attr_type.attr,
1285 	&dev_attr_scsi_level.attr,
1286 	&dev_attr_device_busy.attr,
1287 	&dev_attr_vendor.attr,
1288 	&dev_attr_model.attr,
1289 	&dev_attr_rev.attr,
1290 	&dev_attr_rescan.attr,
1291 	&dev_attr_delete.attr,
1292 	&dev_attr_state.attr,
1293 	&dev_attr_timeout.attr,
1294 	&dev_attr_eh_timeout.attr,
1295 	&dev_attr_iocounterbits.attr,
1296 	&dev_attr_iorequest_cnt.attr,
1297 	&dev_attr_iodone_cnt.attr,
1298 	&dev_attr_ioerr_cnt.attr,
1299 	&dev_attr_iotmo_cnt.attr,
1300 	&dev_attr_modalias.attr,
1301 	&dev_attr_queue_depth.attr,
1302 	&dev_attr_queue_type.attr,
1303 	&dev_attr_wwid.attr,
1304 	&dev_attr_blacklist.attr,
1305 #ifdef CONFIG_SCSI_DH
1306 	&dev_attr_dh_state.attr,
1307 	&dev_attr_access_state.attr,
1308 	&dev_attr_preferred_path.attr,
1309 #endif
1310 	&dev_attr_queue_ramp_up_period.attr,
1311 	REF_EVT(media_change),
1312 	REF_EVT(inquiry_change_reported),
1313 	REF_EVT(capacity_change_reported),
1314 	REF_EVT(soft_threshold_reached),
1315 	REF_EVT(mode_parameter_change_reported),
1316 	REF_EVT(lun_change_reported),
1317 	NULL
1318 };
1319 
1320 static struct bin_attribute *scsi_sdev_bin_attrs[] = {
1321 	&dev_attr_vpd_pg0,
1322 	&dev_attr_vpd_pg83,
1323 	&dev_attr_vpd_pg80,
1324 	&dev_attr_vpd_pg89,
1325 	&dev_attr_vpd_pgb0,
1326 	&dev_attr_vpd_pgb1,
1327 	&dev_attr_vpd_pgb2,
1328 	&dev_attr_inquiry,
1329 	NULL
1330 };
1331 static struct attribute_group scsi_sdev_attr_group = {
1332 	.attrs =	scsi_sdev_attrs,
1333 	.bin_attrs =	scsi_sdev_bin_attrs,
1334 	.is_visible =	scsi_sdev_attr_is_visible,
1335 	.is_bin_visible = scsi_sdev_bin_attr_is_visible,
1336 };
1337 
1338 static const struct attribute_group *scsi_sdev_attr_groups[] = {
1339 	&scsi_sdev_attr_group,
1340 	NULL
1341 };
1342 
1343 static int scsi_target_add(struct scsi_target *starget)
1344 {
1345 	int error;
1346 
1347 	if (starget->state != STARGET_CREATED)
1348 		return 0;
1349 
1350 	error = device_add(&starget->dev);
1351 	if (error) {
1352 		dev_err(&starget->dev, "target device_add failed, error %d\n", error);
1353 		return error;
1354 	}
1355 	transport_add_device(&starget->dev);
1356 	starget->state = STARGET_RUNNING;
1357 
1358 	pm_runtime_set_active(&starget->dev);
1359 	pm_runtime_enable(&starget->dev);
1360 	device_enable_async_suspend(&starget->dev);
1361 
1362 	return 0;
1363 }
1364 
1365 /**
1366  * scsi_sysfs_add_sdev - add scsi device to sysfs
1367  * @sdev:	scsi_device to add
1368  *
1369  * Return value:
1370  * 	0 on Success / non-zero on Failure
1371  **/
1372 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
1373 {
1374 	int error;
1375 	struct scsi_target *starget = sdev->sdev_target;
1376 
1377 	error = scsi_target_add(starget);
1378 	if (error)
1379 		return error;
1380 
1381 	transport_configure_device(&starget->dev);
1382 
1383 	device_enable_async_suspend(&sdev->sdev_gendev);
1384 	scsi_autopm_get_target(starget);
1385 	pm_runtime_set_active(&sdev->sdev_gendev);
1386 	if (!sdev->rpm_autosuspend)
1387 		pm_runtime_forbid(&sdev->sdev_gendev);
1388 	pm_runtime_enable(&sdev->sdev_gendev);
1389 	scsi_autopm_put_target(starget);
1390 
1391 	scsi_autopm_get_device(sdev);
1392 
1393 	scsi_dh_add_device(sdev);
1394 
1395 	error = device_add(&sdev->sdev_gendev);
1396 	if (error) {
1397 		sdev_printk(KERN_INFO, sdev,
1398 				"failed to add device: %d\n", error);
1399 		return error;
1400 	}
1401 
1402 	device_enable_async_suspend(&sdev->sdev_dev);
1403 	error = device_add(&sdev->sdev_dev);
1404 	if (error) {
1405 		sdev_printk(KERN_INFO, sdev,
1406 				"failed to add class device: %d\n", error);
1407 		device_del(&sdev->sdev_gendev);
1408 		return error;
1409 	}
1410 	transport_add_device(&sdev->sdev_gendev);
1411 	sdev->is_visible = 1;
1412 
1413 	if (IS_ENABLED(CONFIG_BLK_DEV_BSG)) {
1414 		sdev->bsg_dev = scsi_bsg_register_queue(sdev);
1415 		if (IS_ERR(sdev->bsg_dev)) {
1416 			error = PTR_ERR(sdev->bsg_dev);
1417 			sdev_printk(KERN_INFO, sdev,
1418 				    "Failed to register bsg queue, errno=%d\n",
1419 				    error);
1420 			sdev->bsg_dev = NULL;
1421 		}
1422 	}
1423 
1424 	scsi_autopm_put_device(sdev);
1425 	return error;
1426 }
1427 
1428 void __scsi_remove_device(struct scsi_device *sdev)
1429 {
1430 	struct device *dev = &sdev->sdev_gendev;
1431 	int res;
1432 
1433 	/*
1434 	 * This cleanup path is not reentrant and while it is impossible
1435 	 * to get a new reference with scsi_device_get() someone can still
1436 	 * hold a previously acquired one.
1437 	 */
1438 	if (sdev->sdev_state == SDEV_DEL)
1439 		return;
1440 
1441 	if (sdev->is_visible) {
1442 		/*
1443 		 * If scsi_internal_target_block() is running concurrently,
1444 		 * wait until it has finished before changing the device state.
1445 		 */
1446 		mutex_lock(&sdev->state_mutex);
1447 		/*
1448 		 * If blocked, we go straight to DEL and restart the queue so
1449 		 * any commands issued during driver shutdown (like sync
1450 		 * cache) are errored immediately.
1451 		 */
1452 		res = scsi_device_set_state(sdev, SDEV_CANCEL);
1453 		if (res != 0) {
1454 			res = scsi_device_set_state(sdev, SDEV_DEL);
1455 			if (res == 0)
1456 				scsi_start_queue(sdev);
1457 		}
1458 		mutex_unlock(&sdev->state_mutex);
1459 
1460 		if (res != 0)
1461 			return;
1462 
1463 		if (IS_ENABLED(CONFIG_BLK_DEV_BSG) && sdev->bsg_dev)
1464 			bsg_unregister_queue(sdev->bsg_dev);
1465 		device_unregister(&sdev->sdev_dev);
1466 		transport_remove_device(dev);
1467 		device_del(dev);
1468 	} else
1469 		put_device(&sdev->sdev_dev);
1470 
1471 	/*
1472 	 * Stop accepting new requests and wait until all queuecommand() and
1473 	 * scsi_run_queue() invocations have finished before tearing down the
1474 	 * device.
1475 	 */
1476 	mutex_lock(&sdev->state_mutex);
1477 	scsi_device_set_state(sdev, SDEV_DEL);
1478 	mutex_unlock(&sdev->state_mutex);
1479 
1480 	blk_mq_destroy_queue(sdev->request_queue);
1481 	kref_put(&sdev->host->tagset_refcnt, scsi_mq_free_tags);
1482 	cancel_work_sync(&sdev->requeue_work);
1483 
1484 	if (sdev->host->hostt->slave_destroy)
1485 		sdev->host->hostt->slave_destroy(sdev);
1486 	transport_destroy_device(dev);
1487 
1488 	/*
1489 	 * Paired with the kref_get() in scsi_sysfs_initialize().  We have
1490 	 * removed sysfs visibility from the device, so make the target
1491 	 * invisible if this was the last device underneath it.
1492 	 */
1493 	scsi_target_reap(scsi_target(sdev));
1494 
1495 	put_device(dev);
1496 }
1497 
1498 /**
1499  * scsi_remove_device - unregister a device from the scsi bus
1500  * @sdev:	scsi_device to unregister
1501  **/
1502 void scsi_remove_device(struct scsi_device *sdev)
1503 {
1504 	struct Scsi_Host *shost = sdev->host;
1505 
1506 	mutex_lock(&shost->scan_mutex);
1507 	__scsi_remove_device(sdev);
1508 	mutex_unlock(&shost->scan_mutex);
1509 }
1510 EXPORT_SYMBOL(scsi_remove_device);
1511 
1512 static void __scsi_remove_target(struct scsi_target *starget)
1513 {
1514 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1515 	unsigned long flags;
1516 	struct scsi_device *sdev;
1517 
1518 	spin_lock_irqsave(shost->host_lock, flags);
1519  restart:
1520 	list_for_each_entry(sdev, &shost->__devices, siblings) {
1521 		/*
1522 		 * We cannot call scsi_device_get() here, as
1523 		 * we might've been called from rmmod() causing
1524 		 * scsi_device_get() to fail the module_is_live()
1525 		 * check.
1526 		 */
1527 		if (sdev->channel != starget->channel ||
1528 		    sdev->id != starget->id)
1529 			continue;
1530 		if (sdev->sdev_state == SDEV_DEL ||
1531 		    sdev->sdev_state == SDEV_CANCEL ||
1532 		    !get_device(&sdev->sdev_gendev))
1533 			continue;
1534 		spin_unlock_irqrestore(shost->host_lock, flags);
1535 		scsi_remove_device(sdev);
1536 		put_device(&sdev->sdev_gendev);
1537 		spin_lock_irqsave(shost->host_lock, flags);
1538 		goto restart;
1539 	}
1540 	spin_unlock_irqrestore(shost->host_lock, flags);
1541 }
1542 
1543 /**
1544  * scsi_remove_target - try to remove a target and all its devices
1545  * @dev: generic starget or parent of generic stargets to be removed
1546  *
1547  * Note: This is slightly racy.  It is possible that if the user
1548  * requests the addition of another device then the target won't be
1549  * removed.
1550  */
1551 void scsi_remove_target(struct device *dev)
1552 {
1553 	struct Scsi_Host *shost = dev_to_shost(dev->parent);
1554 	struct scsi_target *starget;
1555 	unsigned long flags;
1556 
1557 restart:
1558 	spin_lock_irqsave(shost->host_lock, flags);
1559 	list_for_each_entry(starget, &shost->__targets, siblings) {
1560 		if (starget->state == STARGET_DEL ||
1561 		    starget->state == STARGET_REMOVE ||
1562 		    starget->state == STARGET_CREATED_REMOVE)
1563 			continue;
1564 		if (starget->dev.parent == dev || &starget->dev == dev) {
1565 			kref_get(&starget->reap_ref);
1566 			if (starget->state == STARGET_CREATED)
1567 				starget->state = STARGET_CREATED_REMOVE;
1568 			else
1569 				starget->state = STARGET_REMOVE;
1570 			spin_unlock_irqrestore(shost->host_lock, flags);
1571 			__scsi_remove_target(starget);
1572 			scsi_target_reap(starget);
1573 			goto restart;
1574 		}
1575 	}
1576 	spin_unlock_irqrestore(shost->host_lock, flags);
1577 }
1578 EXPORT_SYMBOL(scsi_remove_target);
1579 
1580 int scsi_register_driver(struct device_driver *drv)
1581 {
1582 	drv->bus = &scsi_bus_type;
1583 
1584 	return driver_register(drv);
1585 }
1586 EXPORT_SYMBOL(scsi_register_driver);
1587 
1588 int scsi_register_interface(struct class_interface *intf)
1589 {
1590 	intf->class = &sdev_class;
1591 
1592 	return class_interface_register(intf);
1593 }
1594 EXPORT_SYMBOL(scsi_register_interface);
1595 
1596 /**
1597  * scsi_sysfs_add_host - add scsi host to subsystem
1598  * @shost:     scsi host struct to add to subsystem
1599  **/
1600 int scsi_sysfs_add_host(struct Scsi_Host *shost)
1601 {
1602 	transport_register_device(&shost->shost_gendev);
1603 	transport_configure_device(&shost->shost_gendev);
1604 	return 0;
1605 }
1606 
1607 static struct device_type scsi_dev_type = {
1608 	.name =		"scsi_device",
1609 	.release =	scsi_device_dev_release,
1610 	.groups =	scsi_sdev_attr_groups,
1611 };
1612 
1613 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
1614 {
1615 	unsigned long flags;
1616 	struct Scsi_Host *shost = sdev->host;
1617 	struct scsi_host_template *hostt = shost->hostt;
1618 	struct scsi_target  *starget = sdev->sdev_target;
1619 
1620 	device_initialize(&sdev->sdev_gendev);
1621 	sdev->sdev_gendev.bus = &scsi_bus_type;
1622 	sdev->sdev_gendev.type = &scsi_dev_type;
1623 	scsi_enable_async_suspend(&sdev->sdev_gendev);
1624 	dev_set_name(&sdev->sdev_gendev, "%d:%d:%d:%llu",
1625 		     sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
1626 	sdev->sdev_gendev.groups = hostt->sdev_groups;
1627 
1628 	device_initialize(&sdev->sdev_dev);
1629 	sdev->sdev_dev.parent = get_device(&sdev->sdev_gendev);
1630 	sdev->sdev_dev.class = &sdev_class;
1631 	dev_set_name(&sdev->sdev_dev, "%d:%d:%d:%llu",
1632 		     sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
1633 	/*
1634 	 * Get a default scsi_level from the target (derived from sibling
1635 	 * devices).  This is the best we can do for guessing how to set
1636 	 * sdev->lun_in_cdb for the initial INQUIRY command.  For LUN 0 the
1637 	 * setting doesn't matter, because all the bits are zero anyway.
1638 	 * But it does matter for higher LUNs.
1639 	 */
1640 	sdev->scsi_level = starget->scsi_level;
1641 	if (sdev->scsi_level <= SCSI_2 &&
1642 			sdev->scsi_level != SCSI_UNKNOWN &&
1643 			!shost->no_scsi2_lun_in_cdb)
1644 		sdev->lun_in_cdb = 1;
1645 
1646 	transport_setup_device(&sdev->sdev_gendev);
1647 	spin_lock_irqsave(shost->host_lock, flags);
1648 	list_add_tail(&sdev->same_target_siblings, &starget->devices);
1649 	list_add_tail(&sdev->siblings, &shost->__devices);
1650 	spin_unlock_irqrestore(shost->host_lock, flags);
1651 	/*
1652 	 * device can now only be removed via __scsi_remove_device() so hold
1653 	 * the target.  Target will be held in CREATED state until something
1654 	 * beneath it becomes visible (in which case it moves to RUNNING)
1655 	 */
1656 	kref_get(&starget->reap_ref);
1657 }
1658 
1659 int scsi_is_sdev_device(const struct device *dev)
1660 {
1661 	return dev->type == &scsi_dev_type;
1662 }
1663 EXPORT_SYMBOL(scsi_is_sdev_device);
1664 
1665 /* A blank transport template that is used in drivers that don't
1666  * yet implement Transport Attributes */
1667 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };
1668