xref: /openbmc/linux/drivers/scsi/scsi_sysfs.c (revision 8a10bc9d)
1 /*
2  * scsi_sysfs.c
3  *
4  * SCSI sysfs interface routines.
5  *
6  * Created to pull SCSI mid layer sysfs routines into one file.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/init.h>
12 #include <linux/blkdev.h>
13 #include <linux/device.h>
14 #include <linux/pm_runtime.h>
15 
16 #include <scsi/scsi.h>
17 #include <scsi/scsi_device.h>
18 #include <scsi/scsi_host.h>
19 #include <scsi/scsi_tcq.h>
20 #include <scsi/scsi_transport.h>
21 #include <scsi/scsi_driver.h>
22 
23 #include "scsi_priv.h"
24 #include "scsi_logging.h"
25 
26 static struct device_type scsi_dev_type;
27 
28 static const struct {
29 	enum scsi_device_state	value;
30 	char			*name;
31 } sdev_states[] = {
32 	{ SDEV_CREATED, "created" },
33 	{ SDEV_RUNNING, "running" },
34 	{ SDEV_CANCEL, "cancel" },
35 	{ SDEV_DEL, "deleted" },
36 	{ SDEV_QUIESCE, "quiesce" },
37 	{ SDEV_OFFLINE,	"offline" },
38 	{ SDEV_TRANSPORT_OFFLINE, "transport-offline" },
39 	{ SDEV_BLOCK,	"blocked" },
40 	{ SDEV_CREATED_BLOCK, "created-blocked" },
41 };
42 
43 const char *scsi_device_state_name(enum scsi_device_state state)
44 {
45 	int i;
46 	char *name = NULL;
47 
48 	for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
49 		if (sdev_states[i].value == state) {
50 			name = sdev_states[i].name;
51 			break;
52 		}
53 	}
54 	return name;
55 }
56 
57 static const struct {
58 	enum scsi_host_state	value;
59 	char			*name;
60 } shost_states[] = {
61 	{ SHOST_CREATED, "created" },
62 	{ SHOST_RUNNING, "running" },
63 	{ SHOST_CANCEL, "cancel" },
64 	{ SHOST_DEL, "deleted" },
65 	{ SHOST_RECOVERY, "recovery" },
66 	{ SHOST_CANCEL_RECOVERY, "cancel/recovery" },
67 	{ SHOST_DEL_RECOVERY, "deleted/recovery", },
68 };
69 const char *scsi_host_state_name(enum scsi_host_state state)
70 {
71 	int i;
72 	char *name = NULL;
73 
74 	for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
75 		if (shost_states[i].value == state) {
76 			name = shost_states[i].name;
77 			break;
78 		}
79 	}
80 	return name;
81 }
82 
83 static int check_set(unsigned int *val, char *src)
84 {
85 	char *last;
86 
87 	if (strncmp(src, "-", 20) == 0) {
88 		*val = SCAN_WILD_CARD;
89 	} else {
90 		/*
91 		 * Doesn't check for int overflow
92 		 */
93 		*val = simple_strtoul(src, &last, 0);
94 		if (*last != '\0')
95 			return 1;
96 	}
97 	return 0;
98 }
99 
100 static int scsi_scan(struct Scsi_Host *shost, const char *str)
101 {
102 	char s1[15], s2[15], s3[15], junk;
103 	unsigned int channel, id, lun;
104 	int res;
105 
106 	res = sscanf(str, "%10s %10s %10s %c", s1, s2, s3, &junk);
107 	if (res != 3)
108 		return -EINVAL;
109 	if (check_set(&channel, s1))
110 		return -EINVAL;
111 	if (check_set(&id, s2))
112 		return -EINVAL;
113 	if (check_set(&lun, s3))
114 		return -EINVAL;
115 	if (shost->transportt->user_scan)
116 		res = shost->transportt->user_scan(shost, channel, id, lun);
117 	else
118 		res = scsi_scan_host_selected(shost, channel, id, lun, 1);
119 	return res;
120 }
121 
122 /*
123  * shost_show_function: macro to create an attr function that can be used to
124  * show a non-bit field.
125  */
126 #define shost_show_function(name, field, format_string)			\
127 static ssize_t								\
128 show_##name (struct device *dev, struct device_attribute *attr, 	\
129 	     char *buf)							\
130 {									\
131 	struct Scsi_Host *shost = class_to_shost(dev);			\
132 	return snprintf (buf, 20, format_string, shost->field);		\
133 }
134 
135 /*
136  * shost_rd_attr: macro to create a function and attribute variable for a
137  * read only field.
138  */
139 #define shost_rd_attr2(name, field, format_string)			\
140 	shost_show_function(name, field, format_string)			\
141 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
142 
143 #define shost_rd_attr(field, format_string) \
144 shost_rd_attr2(field, field, format_string)
145 
146 /*
147  * Create the actual show/store functions and data structures.
148  */
149 
150 static ssize_t
151 store_scan(struct device *dev, struct device_attribute *attr,
152 	   const char *buf, size_t count)
153 {
154 	struct Scsi_Host *shost = class_to_shost(dev);
155 	int res;
156 
157 	res = scsi_scan(shost, buf);
158 	if (res == 0)
159 		res = count;
160 	return res;
161 };
162 static DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
163 
164 static ssize_t
165 store_shost_state(struct device *dev, struct device_attribute *attr,
166 		  const char *buf, size_t count)
167 {
168 	int i;
169 	struct Scsi_Host *shost = class_to_shost(dev);
170 	enum scsi_host_state state = 0;
171 
172 	for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
173 		const int len = strlen(shost_states[i].name);
174 		if (strncmp(shost_states[i].name, buf, len) == 0 &&
175 		   buf[len] == '\n') {
176 			state = shost_states[i].value;
177 			break;
178 		}
179 	}
180 	if (!state)
181 		return -EINVAL;
182 
183 	if (scsi_host_set_state(shost, state))
184 		return -EINVAL;
185 	return count;
186 }
187 
188 static ssize_t
189 show_shost_state(struct device *dev, struct device_attribute *attr, char *buf)
190 {
191 	struct Scsi_Host *shost = class_to_shost(dev);
192 	const char *name = scsi_host_state_name(shost->shost_state);
193 
194 	if (!name)
195 		return -EINVAL;
196 
197 	return snprintf(buf, 20, "%s\n", name);
198 }
199 
200 /* DEVICE_ATTR(state) clashes with dev_attr_state for sdev */
201 struct device_attribute dev_attr_hstate =
202 	__ATTR(state, S_IRUGO | S_IWUSR, show_shost_state, store_shost_state);
203 
204 static ssize_t
205 show_shost_mode(unsigned int mode, char *buf)
206 {
207 	ssize_t len = 0;
208 
209 	if (mode & MODE_INITIATOR)
210 		len = sprintf(buf, "%s", "Initiator");
211 
212 	if (mode & MODE_TARGET)
213 		len += sprintf(buf + len, "%s%s", len ? ", " : "", "Target");
214 
215 	len += sprintf(buf + len, "\n");
216 
217 	return len;
218 }
219 
220 static ssize_t
221 show_shost_supported_mode(struct device *dev, struct device_attribute *attr,
222 			  char *buf)
223 {
224 	struct Scsi_Host *shost = class_to_shost(dev);
225 	unsigned int supported_mode = shost->hostt->supported_mode;
226 
227 	if (supported_mode == MODE_UNKNOWN)
228 		/* by default this should be initiator */
229 		supported_mode = MODE_INITIATOR;
230 
231 	return show_shost_mode(supported_mode, buf);
232 }
233 
234 static DEVICE_ATTR(supported_mode, S_IRUGO | S_IWUSR, show_shost_supported_mode, NULL);
235 
236 static ssize_t
237 show_shost_active_mode(struct device *dev,
238 		       struct device_attribute *attr, char *buf)
239 {
240 	struct Scsi_Host *shost = class_to_shost(dev);
241 
242 	if (shost->active_mode == MODE_UNKNOWN)
243 		return snprintf(buf, 20, "unknown\n");
244 	else
245 		return show_shost_mode(shost->active_mode, buf);
246 }
247 
248 static DEVICE_ATTR(active_mode, S_IRUGO | S_IWUSR, show_shost_active_mode, NULL);
249 
250 static int check_reset_type(const char *str)
251 {
252 	if (sysfs_streq(str, "adapter"))
253 		return SCSI_ADAPTER_RESET;
254 	else if (sysfs_streq(str, "firmware"))
255 		return SCSI_FIRMWARE_RESET;
256 	else
257 		return 0;
258 }
259 
260 static ssize_t
261 store_host_reset(struct device *dev, struct device_attribute *attr,
262 		const char *buf, size_t count)
263 {
264 	struct Scsi_Host *shost = class_to_shost(dev);
265 	struct scsi_host_template *sht = shost->hostt;
266 	int ret = -EINVAL;
267 	int type;
268 
269 	type = check_reset_type(buf);
270 	if (!type)
271 		goto exit_store_host_reset;
272 
273 	if (sht->host_reset)
274 		ret = sht->host_reset(shost, type);
275 
276 exit_store_host_reset:
277 	if (ret == 0)
278 		ret = count;
279 	return ret;
280 }
281 
282 static DEVICE_ATTR(host_reset, S_IWUSR, NULL, store_host_reset);
283 
284 static ssize_t
285 show_shost_eh_deadline(struct device *dev,
286 		      struct device_attribute *attr, char *buf)
287 {
288 	struct Scsi_Host *shost = class_to_shost(dev);
289 
290 	if (shost->eh_deadline == -1)
291 		return snprintf(buf, strlen("off") + 2, "off\n");
292 	return sprintf(buf, "%u\n", shost->eh_deadline / HZ);
293 }
294 
295 static ssize_t
296 store_shost_eh_deadline(struct device *dev, struct device_attribute *attr,
297 		const char *buf, size_t count)
298 {
299 	struct Scsi_Host *shost = class_to_shost(dev);
300 	int ret = -EINVAL;
301 	unsigned long deadline, flags;
302 
303 	if (shost->transportt && shost->transportt->eh_strategy_handler)
304 		return ret;
305 
306 	if (!strncmp(buf, "off", strlen("off")))
307 		deadline = -1;
308 	else {
309 		ret = kstrtoul(buf, 10, &deadline);
310 		if (ret)
311 			return ret;
312 		if (deadline * HZ > UINT_MAX)
313 			return -EINVAL;
314 	}
315 
316 	spin_lock_irqsave(shost->host_lock, flags);
317 	if (scsi_host_in_recovery(shost))
318 		ret = -EBUSY;
319 	else {
320 		if (deadline == -1)
321 			shost->eh_deadline = -1;
322 		else
323 			shost->eh_deadline = deadline * HZ;
324 
325 		ret = count;
326 	}
327 	spin_unlock_irqrestore(shost->host_lock, flags);
328 
329 	return ret;
330 }
331 
332 static DEVICE_ATTR(eh_deadline, S_IRUGO | S_IWUSR, show_shost_eh_deadline, store_shost_eh_deadline);
333 
334 shost_rd_attr(unique_id, "%u\n");
335 shost_rd_attr(host_busy, "%hu\n");
336 shost_rd_attr(cmd_per_lun, "%hd\n");
337 shost_rd_attr(can_queue, "%hd\n");
338 shost_rd_attr(sg_tablesize, "%hu\n");
339 shost_rd_attr(sg_prot_tablesize, "%hu\n");
340 shost_rd_attr(unchecked_isa_dma, "%d\n");
341 shost_rd_attr(prot_capabilities, "%u\n");
342 shost_rd_attr(prot_guard_type, "%hd\n");
343 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
344 
345 static struct attribute *scsi_sysfs_shost_attrs[] = {
346 	&dev_attr_unique_id.attr,
347 	&dev_attr_host_busy.attr,
348 	&dev_attr_cmd_per_lun.attr,
349 	&dev_attr_can_queue.attr,
350 	&dev_attr_sg_tablesize.attr,
351 	&dev_attr_sg_prot_tablesize.attr,
352 	&dev_attr_unchecked_isa_dma.attr,
353 	&dev_attr_proc_name.attr,
354 	&dev_attr_scan.attr,
355 	&dev_attr_hstate.attr,
356 	&dev_attr_supported_mode.attr,
357 	&dev_attr_active_mode.attr,
358 	&dev_attr_prot_capabilities.attr,
359 	&dev_attr_prot_guard_type.attr,
360 	&dev_attr_host_reset.attr,
361 	&dev_attr_eh_deadline.attr,
362 	NULL
363 };
364 
365 struct attribute_group scsi_shost_attr_group = {
366 	.attrs =	scsi_sysfs_shost_attrs,
367 };
368 
369 const struct attribute_group *scsi_sysfs_shost_attr_groups[] = {
370 	&scsi_shost_attr_group,
371 	NULL
372 };
373 
374 static void scsi_device_cls_release(struct device *class_dev)
375 {
376 	struct scsi_device *sdev;
377 
378 	sdev = class_to_sdev(class_dev);
379 	put_device(&sdev->sdev_gendev);
380 }
381 
382 static void scsi_device_dev_release_usercontext(struct work_struct *work)
383 {
384 	struct scsi_device *sdev;
385 	struct device *parent;
386 	struct scsi_target *starget;
387 	struct list_head *this, *tmp;
388 	unsigned long flags;
389 
390 	sdev = container_of(work, struct scsi_device, ew.work);
391 
392 	parent = sdev->sdev_gendev.parent;
393 	starget = to_scsi_target(parent);
394 
395 	spin_lock_irqsave(sdev->host->host_lock, flags);
396 	starget->reap_ref++;
397 	list_del(&sdev->siblings);
398 	list_del(&sdev->same_target_siblings);
399 	list_del(&sdev->starved_entry);
400 	spin_unlock_irqrestore(sdev->host->host_lock, flags);
401 
402 	cancel_work_sync(&sdev->event_work);
403 
404 	list_for_each_safe(this, tmp, &sdev->event_list) {
405 		struct scsi_event *evt;
406 
407 		evt = list_entry(this, struct scsi_event, node);
408 		list_del(&evt->node);
409 		kfree(evt);
410 	}
411 
412 	blk_put_queue(sdev->request_queue);
413 	/* NULL queue means the device can't be used */
414 	sdev->request_queue = NULL;
415 
416 	scsi_target_reap(scsi_target(sdev));
417 
418 	kfree(sdev->inquiry);
419 	kfree(sdev);
420 
421 	if (parent)
422 		put_device(parent);
423 }
424 
425 static void scsi_device_dev_release(struct device *dev)
426 {
427 	struct scsi_device *sdp = to_scsi_device(dev);
428 	execute_in_process_context(scsi_device_dev_release_usercontext,
429 				   &sdp->ew);
430 }
431 
432 static struct class sdev_class = {
433 	.name		= "scsi_device",
434 	.dev_release	= scsi_device_cls_release,
435 };
436 
437 /* all probing is done in the individual ->probe routines */
438 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
439 {
440 	struct scsi_device *sdp;
441 
442 	if (dev->type != &scsi_dev_type)
443 		return 0;
444 
445 	sdp = to_scsi_device(dev);
446 	if (sdp->no_uld_attach)
447 		return 0;
448 	return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
449 }
450 
451 static int scsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
452 {
453 	struct scsi_device *sdev;
454 
455 	if (dev->type != &scsi_dev_type)
456 		return 0;
457 
458 	sdev = to_scsi_device(dev);
459 
460 	add_uevent_var(env, "MODALIAS=" SCSI_DEVICE_MODALIAS_FMT, sdev->type);
461 	return 0;
462 }
463 
464 struct bus_type scsi_bus_type = {
465         .name		= "scsi",
466         .match		= scsi_bus_match,
467 	.uevent		= scsi_bus_uevent,
468 #ifdef CONFIG_PM
469 	.pm		= &scsi_bus_pm_ops,
470 #endif
471 };
472 EXPORT_SYMBOL_GPL(scsi_bus_type);
473 
474 int scsi_sysfs_register(void)
475 {
476 	int error;
477 
478 	error = bus_register(&scsi_bus_type);
479 	if (!error) {
480 		error = class_register(&sdev_class);
481 		if (error)
482 			bus_unregister(&scsi_bus_type);
483 	}
484 
485 	return error;
486 }
487 
488 void scsi_sysfs_unregister(void)
489 {
490 	class_unregister(&sdev_class);
491 	bus_unregister(&scsi_bus_type);
492 }
493 
494 /*
495  * sdev_show_function: macro to create an attr function that can be used to
496  * show a non-bit field.
497  */
498 #define sdev_show_function(field, format_string)				\
499 static ssize_t								\
500 sdev_show_##field (struct device *dev, struct device_attribute *attr,	\
501 		   char *buf)						\
502 {									\
503 	struct scsi_device *sdev;					\
504 	sdev = to_scsi_device(dev);					\
505 	return snprintf (buf, 20, format_string, sdev->field);		\
506 }									\
507 
508 /*
509  * sdev_rd_attr: macro to create a function and attribute variable for a
510  * read only field.
511  */
512 #define sdev_rd_attr(field, format_string)				\
513 	sdev_show_function(field, format_string)			\
514 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
515 
516 
517 /*
518  * sdev_rw_attr: create a function and attribute variable for a
519  * read/write field.
520  */
521 #define sdev_rw_attr(field, format_string)				\
522 	sdev_show_function(field, format_string)				\
523 									\
524 static ssize_t								\
525 sdev_store_##field (struct device *dev, struct device_attribute *attr,	\
526 		    const char *buf, size_t count)			\
527 {									\
528 	struct scsi_device *sdev;					\
529 	sdev = to_scsi_device(dev);					\
530 	sscanf (buf, format_string, &sdev->field);			\
531 	return count;							\
532 }									\
533 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
534 
535 /* Currently we don't export bit fields, but we might in future,
536  * so leave this code in */
537 #if 0
538 /*
539  * sdev_rd_attr: create a function and attribute variable for a
540  * read/write bit field.
541  */
542 #define sdev_rw_attr_bit(field)						\
543 	sdev_show_function(field, "%d\n")					\
544 									\
545 static ssize_t								\
546 sdev_store_##field (struct device *dev, struct device_attribute *attr,	\
547 		    const char *buf, size_t count)			\
548 {									\
549 	int ret;							\
550 	struct scsi_device *sdev;					\
551 	ret = scsi_sdev_check_buf_bit(buf);				\
552 	if (ret >= 0)	{						\
553 		sdev = to_scsi_device(dev);				\
554 		sdev->field = ret;					\
555 		ret = count;						\
556 	}								\
557 	return ret;							\
558 }									\
559 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
560 
561 /*
562  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
563  * else return -EINVAL.
564  */
565 static int scsi_sdev_check_buf_bit(const char *buf)
566 {
567 	if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
568 		if (buf[0] == '1')
569 			return 1;
570 		else if (buf[0] == '0')
571 			return 0;
572 		else
573 			return -EINVAL;
574 	} else
575 		return -EINVAL;
576 }
577 #endif
578 /*
579  * Create the actual show/store functions and data structures.
580  */
581 sdev_rd_attr (device_blocked, "%d\n");
582 sdev_rd_attr (queue_depth, "%d\n");
583 sdev_rd_attr (device_busy, "%d\n");
584 sdev_rd_attr (type, "%d\n");
585 sdev_rd_attr (scsi_level, "%d\n");
586 sdev_rd_attr (vendor, "%.8s\n");
587 sdev_rd_attr (model, "%.16s\n");
588 sdev_rd_attr (rev, "%.4s\n");
589 
590 /*
591  * TODO: can we make these symlinks to the block layer ones?
592  */
593 static ssize_t
594 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
595 {
596 	struct scsi_device *sdev;
597 	sdev = to_scsi_device(dev);
598 	return snprintf(buf, 20, "%d\n", sdev->request_queue->rq_timeout / HZ);
599 }
600 
601 static ssize_t
602 sdev_store_timeout (struct device *dev, struct device_attribute *attr,
603 		    const char *buf, size_t count)
604 {
605 	struct scsi_device *sdev;
606 	int timeout;
607 	sdev = to_scsi_device(dev);
608 	sscanf (buf, "%d\n", &timeout);
609 	blk_queue_rq_timeout(sdev->request_queue, timeout * HZ);
610 	return count;
611 }
612 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
613 
614 static ssize_t
615 sdev_show_eh_timeout(struct device *dev, struct device_attribute *attr, char *buf)
616 {
617 	struct scsi_device *sdev;
618 	sdev = to_scsi_device(dev);
619 	return snprintf(buf, 20, "%u\n", sdev->eh_timeout / HZ);
620 }
621 
622 static ssize_t
623 sdev_store_eh_timeout(struct device *dev, struct device_attribute *attr,
624 		    const char *buf, size_t count)
625 {
626 	struct scsi_device *sdev;
627 	unsigned int eh_timeout;
628 	int err;
629 
630 	if (!capable(CAP_SYS_ADMIN))
631 		return -EACCES;
632 
633 	sdev = to_scsi_device(dev);
634 	err = kstrtouint(buf, 10, &eh_timeout);
635 	if (err)
636 		return err;
637 	sdev->eh_timeout = eh_timeout * HZ;
638 
639 	return count;
640 }
641 static DEVICE_ATTR(eh_timeout, S_IRUGO | S_IWUSR, sdev_show_eh_timeout, sdev_store_eh_timeout);
642 
643 static ssize_t
644 store_rescan_field (struct device *dev, struct device_attribute *attr,
645 		    const char *buf, size_t count)
646 {
647 	scsi_rescan_device(dev);
648 	return count;
649 }
650 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
651 
652 static void sdev_store_delete_callback(struct device *dev)
653 {
654 	scsi_remove_device(to_scsi_device(dev));
655 }
656 
657 static ssize_t
658 sdev_store_delete(struct device *dev, struct device_attribute *attr,
659 		  const char *buf, size_t count)
660 {
661 	int rc;
662 
663 	/* An attribute cannot be unregistered by one of its own methods,
664 	 * so we have to use this roundabout approach.
665 	 */
666 	rc = device_schedule_callback(dev, sdev_store_delete_callback);
667 	if (rc)
668 		count = rc;
669 	return count;
670 };
671 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
672 
673 static ssize_t
674 store_state_field(struct device *dev, struct device_attribute *attr,
675 		  const char *buf, size_t count)
676 {
677 	int i;
678 	struct scsi_device *sdev = to_scsi_device(dev);
679 	enum scsi_device_state state = 0;
680 
681 	for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
682 		const int len = strlen(sdev_states[i].name);
683 		if (strncmp(sdev_states[i].name, buf, len) == 0 &&
684 		   buf[len] == '\n') {
685 			state = sdev_states[i].value;
686 			break;
687 		}
688 	}
689 	if (!state)
690 		return -EINVAL;
691 
692 	if (scsi_device_set_state(sdev, state))
693 		return -EINVAL;
694 	return count;
695 }
696 
697 static ssize_t
698 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
699 {
700 	struct scsi_device *sdev = to_scsi_device(dev);
701 	const char *name = scsi_device_state_name(sdev->sdev_state);
702 
703 	if (!name)
704 		return -EINVAL;
705 
706 	return snprintf(buf, 20, "%s\n", name);
707 }
708 
709 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
710 
711 static ssize_t
712 show_queue_type_field(struct device *dev, struct device_attribute *attr,
713 		      char *buf)
714 {
715 	struct scsi_device *sdev = to_scsi_device(dev);
716 	const char *name = "none";
717 
718 	if (sdev->ordered_tags)
719 		name = "ordered";
720 	else if (sdev->simple_tags)
721 		name = "simple";
722 
723 	return snprintf(buf, 20, "%s\n", name);
724 }
725 
726 static DEVICE_ATTR(queue_type, S_IRUGO, show_queue_type_field, NULL);
727 
728 static ssize_t
729 show_iostat_counterbits(struct device *dev, struct device_attribute *attr, 				char *buf)
730 {
731 	return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
732 }
733 
734 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
735 
736 #define show_sdev_iostat(field)						\
737 static ssize_t								\
738 show_iostat_##field(struct device *dev, struct device_attribute *attr,	\
739 		    char *buf)						\
740 {									\
741 	struct scsi_device *sdev = to_scsi_device(dev);			\
742 	unsigned long long count = atomic_read(&sdev->field);		\
743 	return snprintf(buf, 20, "0x%llx\n", count);			\
744 }									\
745 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
746 
747 show_sdev_iostat(iorequest_cnt);
748 show_sdev_iostat(iodone_cnt);
749 show_sdev_iostat(ioerr_cnt);
750 
751 static ssize_t
752 sdev_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
753 {
754 	struct scsi_device *sdev;
755 	sdev = to_scsi_device(dev);
756 	return snprintf (buf, 20, SCSI_DEVICE_MODALIAS_FMT "\n", sdev->type);
757 }
758 static DEVICE_ATTR(modalias, S_IRUGO, sdev_show_modalias, NULL);
759 
760 #define DECLARE_EVT_SHOW(name, Cap_name)				\
761 static ssize_t								\
762 sdev_show_evt_##name(struct device *dev, struct device_attribute *attr,	\
763 		     char *buf)						\
764 {									\
765 	struct scsi_device *sdev = to_scsi_device(dev);			\
766 	int val = test_bit(SDEV_EVT_##Cap_name, sdev->supported_events);\
767 	return snprintf(buf, 20, "%d\n", val);				\
768 }
769 
770 #define DECLARE_EVT_STORE(name, Cap_name)				\
771 static ssize_t								\
772 sdev_store_evt_##name(struct device *dev, struct device_attribute *attr,\
773 		      const char *buf, size_t count)			\
774 {									\
775 	struct scsi_device *sdev = to_scsi_device(dev);			\
776 	int val = simple_strtoul(buf, NULL, 0);				\
777 	if (val == 0)							\
778 		clear_bit(SDEV_EVT_##Cap_name, sdev->supported_events);	\
779 	else if (val == 1)						\
780 		set_bit(SDEV_EVT_##Cap_name, sdev->supported_events);	\
781 	else								\
782 		return -EINVAL;						\
783 	return count;							\
784 }
785 
786 #define DECLARE_EVT(name, Cap_name)					\
787 	DECLARE_EVT_SHOW(name, Cap_name)				\
788 	DECLARE_EVT_STORE(name, Cap_name)				\
789 	static DEVICE_ATTR(evt_##name, S_IRUGO, sdev_show_evt_##name,	\
790 			   sdev_store_evt_##name);
791 #define REF_EVT(name) &dev_attr_evt_##name.attr
792 
793 DECLARE_EVT(media_change, MEDIA_CHANGE)
794 DECLARE_EVT(inquiry_change_reported, INQUIRY_CHANGE_REPORTED)
795 DECLARE_EVT(capacity_change_reported, CAPACITY_CHANGE_REPORTED)
796 DECLARE_EVT(soft_threshold_reached, SOFT_THRESHOLD_REACHED_REPORTED)
797 DECLARE_EVT(mode_parameter_change_reported, MODE_PARAMETER_CHANGE_REPORTED)
798 DECLARE_EVT(lun_change_reported, LUN_CHANGE_REPORTED)
799 
800 /* Default template for device attributes.  May NOT be modified */
801 static struct attribute *scsi_sdev_attrs[] = {
802 	&dev_attr_device_blocked.attr,
803 	&dev_attr_type.attr,
804 	&dev_attr_scsi_level.attr,
805 	&dev_attr_device_busy.attr,
806 	&dev_attr_vendor.attr,
807 	&dev_attr_model.attr,
808 	&dev_attr_rev.attr,
809 	&dev_attr_rescan.attr,
810 	&dev_attr_delete.attr,
811 	&dev_attr_state.attr,
812 	&dev_attr_timeout.attr,
813 	&dev_attr_eh_timeout.attr,
814 	&dev_attr_iocounterbits.attr,
815 	&dev_attr_iorequest_cnt.attr,
816 	&dev_attr_iodone_cnt.attr,
817 	&dev_attr_ioerr_cnt.attr,
818 	&dev_attr_modalias.attr,
819 	REF_EVT(media_change),
820 	REF_EVT(inquiry_change_reported),
821 	REF_EVT(capacity_change_reported),
822 	REF_EVT(soft_threshold_reached),
823 	REF_EVT(mode_parameter_change_reported),
824 	REF_EVT(lun_change_reported),
825 	NULL
826 };
827 
828 static struct attribute_group scsi_sdev_attr_group = {
829 	.attrs =	scsi_sdev_attrs,
830 };
831 
832 static const struct attribute_group *scsi_sdev_attr_groups[] = {
833 	&scsi_sdev_attr_group,
834 	NULL
835 };
836 
837 static ssize_t
838 sdev_store_queue_depth_rw(struct device *dev, struct device_attribute *attr,
839 			  const char *buf, size_t count)
840 {
841 	int depth, retval;
842 	struct scsi_device *sdev = to_scsi_device(dev);
843 	struct scsi_host_template *sht = sdev->host->hostt;
844 
845 	if (!sht->change_queue_depth)
846 		return -EINVAL;
847 
848 	depth = simple_strtoul(buf, NULL, 0);
849 
850 	if (depth < 1)
851 		return -EINVAL;
852 
853 	retval = sht->change_queue_depth(sdev, depth,
854 					 SCSI_QDEPTH_DEFAULT);
855 	if (retval < 0)
856 		return retval;
857 
858 	sdev->max_queue_depth = sdev->queue_depth;
859 
860 	return count;
861 }
862 
863 static struct device_attribute sdev_attr_queue_depth_rw =
864 	__ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
865 	       sdev_store_queue_depth_rw);
866 
867 static ssize_t
868 sdev_show_queue_ramp_up_period(struct device *dev,
869 			       struct device_attribute *attr,
870 			       char *buf)
871 {
872 	struct scsi_device *sdev;
873 	sdev = to_scsi_device(dev);
874 	return snprintf(buf, 20, "%u\n",
875 			jiffies_to_msecs(sdev->queue_ramp_up_period));
876 }
877 
878 static ssize_t
879 sdev_store_queue_ramp_up_period(struct device *dev,
880 				struct device_attribute *attr,
881 				const char *buf, size_t count)
882 {
883 	struct scsi_device *sdev = to_scsi_device(dev);
884 	unsigned long period;
885 
886 	if (strict_strtoul(buf, 10, &period))
887 		return -EINVAL;
888 
889 	sdev->queue_ramp_up_period = msecs_to_jiffies(period);
890 	return period;
891 }
892 
893 static struct device_attribute sdev_attr_queue_ramp_up_period =
894 	__ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR,
895 	       sdev_show_queue_ramp_up_period,
896 	       sdev_store_queue_ramp_up_period);
897 
898 static ssize_t
899 sdev_store_queue_type_rw(struct device *dev, struct device_attribute *attr,
900 			 const char *buf, size_t count)
901 {
902 	struct scsi_device *sdev = to_scsi_device(dev);
903 	struct scsi_host_template *sht = sdev->host->hostt;
904 	int tag_type = 0, retval;
905 	int prev_tag_type = scsi_get_tag_type(sdev);
906 
907 	if (!sdev->tagged_supported || !sht->change_queue_type)
908 		return -EINVAL;
909 
910 	if (strncmp(buf, "ordered", 7) == 0)
911 		tag_type = MSG_ORDERED_TAG;
912 	else if (strncmp(buf, "simple", 6) == 0)
913 		tag_type = MSG_SIMPLE_TAG;
914 	else if (strncmp(buf, "none", 4) != 0)
915 		return -EINVAL;
916 
917 	if (tag_type == prev_tag_type)
918 		return count;
919 
920 	retval = sht->change_queue_type(sdev, tag_type);
921 	if (retval < 0)
922 		return retval;
923 
924 	return count;
925 }
926 
927 static int scsi_target_add(struct scsi_target *starget)
928 {
929 	int error;
930 
931 	if (starget->state != STARGET_CREATED)
932 		return 0;
933 
934 	error = device_add(&starget->dev);
935 	if (error) {
936 		dev_err(&starget->dev, "target device_add failed, error %d\n", error);
937 		return error;
938 	}
939 	transport_add_device(&starget->dev);
940 	starget->state = STARGET_RUNNING;
941 
942 	pm_runtime_set_active(&starget->dev);
943 	pm_runtime_enable(&starget->dev);
944 	device_enable_async_suspend(&starget->dev);
945 
946 	return 0;
947 }
948 
949 static struct device_attribute sdev_attr_queue_type_rw =
950 	__ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
951 	       sdev_store_queue_type_rw);
952 
953 /**
954  * scsi_sysfs_add_sdev - add scsi device to sysfs
955  * @sdev:	scsi_device to add
956  *
957  * Return value:
958  * 	0 on Success / non-zero on Failure
959  **/
960 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
961 {
962 	int error, i;
963 	struct request_queue *rq = sdev->request_queue;
964 	struct scsi_target *starget = sdev->sdev_target;
965 
966 	error = scsi_device_set_state(sdev, SDEV_RUNNING);
967 	if (error)
968 		return error;
969 
970 	error = scsi_target_add(starget);
971 	if (error)
972 		return error;
973 
974 	transport_configure_device(&starget->dev);
975 
976 	device_enable_async_suspend(&sdev->sdev_gendev);
977 	scsi_autopm_get_target(starget);
978 	pm_runtime_set_active(&sdev->sdev_gendev);
979 	pm_runtime_forbid(&sdev->sdev_gendev);
980 	pm_runtime_enable(&sdev->sdev_gendev);
981 	scsi_autopm_put_target(starget);
982 
983 	/* The following call will keep sdev active indefinitely, until
984 	 * its driver does a corresponding scsi_autopm_pm_device().  Only
985 	 * drivers supporting autosuspend will do this.
986 	 */
987 	scsi_autopm_get_device(sdev);
988 
989 	error = device_add(&sdev->sdev_gendev);
990 	if (error) {
991 		sdev_printk(KERN_INFO, sdev,
992 				"failed to add device: %d\n", error);
993 		return error;
994 	}
995 	device_enable_async_suspend(&sdev->sdev_dev);
996 	error = device_add(&sdev->sdev_dev);
997 	if (error) {
998 		sdev_printk(KERN_INFO, sdev,
999 				"failed to add class device: %d\n", error);
1000 		device_del(&sdev->sdev_gendev);
1001 		return error;
1002 	}
1003 	transport_add_device(&sdev->sdev_gendev);
1004 	sdev->is_visible = 1;
1005 
1006 	/* create queue files, which may be writable, depending on the host */
1007 	if (sdev->host->hostt->change_queue_depth) {
1008 		error = device_create_file(&sdev->sdev_gendev,
1009 					   &sdev_attr_queue_depth_rw);
1010 		error = device_create_file(&sdev->sdev_gendev,
1011 					   &sdev_attr_queue_ramp_up_period);
1012 	}
1013 	else
1014 		error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_depth);
1015 	if (error)
1016 		return error;
1017 
1018 	if (sdev->host->hostt->change_queue_type)
1019 		error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_type_rw);
1020 	else
1021 		error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_type);
1022 	if (error)
1023 		return error;
1024 
1025 	error = bsg_register_queue(rq, &sdev->sdev_gendev, NULL, NULL);
1026 
1027 	if (error)
1028 		/* we're treating error on bsg register as non-fatal,
1029 		 * so pretend nothing went wrong */
1030 		sdev_printk(KERN_INFO, sdev,
1031 			    "Failed to register bsg queue, errno=%d\n", error);
1032 
1033 	/* add additional host specific attributes */
1034 	if (sdev->host->hostt->sdev_attrs) {
1035 		for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
1036 			error = device_create_file(&sdev->sdev_gendev,
1037 					sdev->host->hostt->sdev_attrs[i]);
1038 			if (error)
1039 				return error;
1040 		}
1041 	}
1042 
1043 	return error;
1044 }
1045 
1046 void __scsi_remove_device(struct scsi_device *sdev)
1047 {
1048 	struct device *dev = &sdev->sdev_gendev;
1049 
1050 	if (sdev->is_visible) {
1051 		if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
1052 			return;
1053 
1054 		bsg_unregister_queue(sdev->request_queue);
1055 		device_unregister(&sdev->sdev_dev);
1056 		transport_remove_device(dev);
1057 		device_del(dev);
1058 	} else
1059 		put_device(&sdev->sdev_dev);
1060 
1061 	/*
1062 	 * Stop accepting new requests and wait until all queuecommand() and
1063 	 * scsi_run_queue() invocations have finished before tearing down the
1064 	 * device.
1065 	 */
1066 	scsi_device_set_state(sdev, SDEV_DEL);
1067 	blk_cleanup_queue(sdev->request_queue);
1068 	cancel_work_sync(&sdev->requeue_work);
1069 
1070 	if (sdev->host->hostt->slave_destroy)
1071 		sdev->host->hostt->slave_destroy(sdev);
1072 	transport_destroy_device(dev);
1073 
1074 	put_device(dev);
1075 }
1076 
1077 /**
1078  * scsi_remove_device - unregister a device from the scsi bus
1079  * @sdev:	scsi_device to unregister
1080  **/
1081 void scsi_remove_device(struct scsi_device *sdev)
1082 {
1083 	struct Scsi_Host *shost = sdev->host;
1084 
1085 	mutex_lock(&shost->scan_mutex);
1086 	__scsi_remove_device(sdev);
1087 	mutex_unlock(&shost->scan_mutex);
1088 }
1089 EXPORT_SYMBOL(scsi_remove_device);
1090 
1091 static void __scsi_remove_target(struct scsi_target *starget)
1092 {
1093 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1094 	unsigned long flags;
1095 	struct scsi_device *sdev;
1096 
1097 	spin_lock_irqsave(shost->host_lock, flags);
1098  restart:
1099 	list_for_each_entry(sdev, &shost->__devices, siblings) {
1100 		if (sdev->channel != starget->channel ||
1101 		    sdev->id != starget->id ||
1102 		    scsi_device_get(sdev))
1103 			continue;
1104 		spin_unlock_irqrestore(shost->host_lock, flags);
1105 		scsi_remove_device(sdev);
1106 		scsi_device_put(sdev);
1107 		spin_lock_irqsave(shost->host_lock, flags);
1108 		goto restart;
1109 	}
1110 	spin_unlock_irqrestore(shost->host_lock, flags);
1111 }
1112 
1113 /**
1114  * scsi_remove_target - try to remove a target and all its devices
1115  * @dev: generic starget or parent of generic stargets to be removed
1116  *
1117  * Note: This is slightly racy.  It is possible that if the user
1118  * requests the addition of another device then the target won't be
1119  * removed.
1120  */
1121 void scsi_remove_target(struct device *dev)
1122 {
1123 	struct Scsi_Host *shost = dev_to_shost(dev->parent);
1124 	struct scsi_target *starget, *last = NULL;
1125 	unsigned long flags;
1126 
1127 	/* remove targets being careful to lookup next entry before
1128 	 * deleting the last
1129 	 */
1130 	spin_lock_irqsave(shost->host_lock, flags);
1131 	list_for_each_entry(starget, &shost->__targets, siblings) {
1132 		if (starget->state == STARGET_DEL)
1133 			continue;
1134 		if (starget->dev.parent == dev || &starget->dev == dev) {
1135 			/* assuming new targets arrive at the end */
1136 			starget->reap_ref++;
1137 			spin_unlock_irqrestore(shost->host_lock, flags);
1138 			if (last)
1139 				scsi_target_reap(last);
1140 			last = starget;
1141 			__scsi_remove_target(starget);
1142 			spin_lock_irqsave(shost->host_lock, flags);
1143 		}
1144 	}
1145 	spin_unlock_irqrestore(shost->host_lock, flags);
1146 
1147 	if (last)
1148 		scsi_target_reap(last);
1149 }
1150 EXPORT_SYMBOL(scsi_remove_target);
1151 
1152 int scsi_register_driver(struct device_driver *drv)
1153 {
1154 	drv->bus = &scsi_bus_type;
1155 
1156 	return driver_register(drv);
1157 }
1158 EXPORT_SYMBOL(scsi_register_driver);
1159 
1160 int scsi_register_interface(struct class_interface *intf)
1161 {
1162 	intf->class = &sdev_class;
1163 
1164 	return class_interface_register(intf);
1165 }
1166 EXPORT_SYMBOL(scsi_register_interface);
1167 
1168 /**
1169  * scsi_sysfs_add_host - add scsi host to subsystem
1170  * @shost:     scsi host struct to add to subsystem
1171  **/
1172 int scsi_sysfs_add_host(struct Scsi_Host *shost)
1173 {
1174 	int error, i;
1175 
1176 	/* add host specific attributes */
1177 	if (shost->hostt->shost_attrs) {
1178 		for (i = 0; shost->hostt->shost_attrs[i]; i++) {
1179 			error = device_create_file(&shost->shost_dev,
1180 					shost->hostt->shost_attrs[i]);
1181 			if (error)
1182 				return error;
1183 		}
1184 	}
1185 
1186 	transport_register_device(&shost->shost_gendev);
1187 	transport_configure_device(&shost->shost_gendev);
1188 	return 0;
1189 }
1190 
1191 static struct device_type scsi_dev_type = {
1192 	.name =		"scsi_device",
1193 	.release =	scsi_device_dev_release,
1194 	.groups =	scsi_sdev_attr_groups,
1195 };
1196 
1197 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
1198 {
1199 	unsigned long flags;
1200 	struct Scsi_Host *shost = sdev->host;
1201 	struct scsi_target  *starget = sdev->sdev_target;
1202 
1203 	device_initialize(&sdev->sdev_gendev);
1204 	sdev->sdev_gendev.bus = &scsi_bus_type;
1205 	sdev->sdev_gendev.type = &scsi_dev_type;
1206 	dev_set_name(&sdev->sdev_gendev, "%d:%d:%d:%d",
1207 		     sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
1208 
1209 	device_initialize(&sdev->sdev_dev);
1210 	sdev->sdev_dev.parent = get_device(&sdev->sdev_gendev);
1211 	sdev->sdev_dev.class = &sdev_class;
1212 	dev_set_name(&sdev->sdev_dev, "%d:%d:%d:%d",
1213 		     sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
1214 	sdev->scsi_level = starget->scsi_level;
1215 	transport_setup_device(&sdev->sdev_gendev);
1216 	spin_lock_irqsave(shost->host_lock, flags);
1217 	list_add_tail(&sdev->same_target_siblings, &starget->devices);
1218 	list_add_tail(&sdev->siblings, &shost->__devices);
1219 	spin_unlock_irqrestore(shost->host_lock, flags);
1220 }
1221 
1222 int scsi_is_sdev_device(const struct device *dev)
1223 {
1224 	return dev->type == &scsi_dev_type;
1225 }
1226 EXPORT_SYMBOL(scsi_is_sdev_device);
1227 
1228 /* A blank transport template that is used in drivers that don't
1229  * yet implement Transport Attributes */
1230 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };
1231