xref: /linux/drivers/scsi/scsi_sysfs.c (revision 98366c20a275e957416e9516db5dcb7195b4e101)
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/init.h>
11 #include <linux/blkdev.h>
12 #include <linux/device.h>
13 
14 #include <scsi/scsi.h>
15 #include <scsi/scsi_device.h>
16 #include <scsi/scsi_host.h>
17 #include <scsi/scsi_tcq.h>
18 #include <scsi/scsi_transport.h>
19 #include <scsi/scsi_driver.h>
20 
21 #include "scsi_priv.h"
22 #include "scsi_logging.h"
23 
24 static const struct {
25 	enum scsi_device_state	value;
26 	char			*name;
27 } sdev_states[] = {
28 	{ SDEV_CREATED, "created" },
29 	{ SDEV_RUNNING, "running" },
30 	{ SDEV_CANCEL, "cancel" },
31 	{ SDEV_DEL, "deleted" },
32 	{ SDEV_QUIESCE, "quiesce" },
33 	{ SDEV_OFFLINE,	"offline" },
34 	{ SDEV_BLOCK,	"blocked" },
35 };
36 
37 const char *scsi_device_state_name(enum scsi_device_state state)
38 {
39 	int i;
40 	char *name = NULL;
41 
42 	for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
43 		if (sdev_states[i].value == state) {
44 			name = sdev_states[i].name;
45 			break;
46 		}
47 	}
48 	return name;
49 }
50 
51 static const struct {
52 	enum scsi_host_state	value;
53 	char			*name;
54 } shost_states[] = {
55 	{ SHOST_CREATED, "created" },
56 	{ SHOST_RUNNING, "running" },
57 	{ SHOST_CANCEL, "cancel" },
58 	{ SHOST_DEL, "deleted" },
59 	{ SHOST_RECOVERY, "recovery" },
60 	{ SHOST_CANCEL_RECOVERY, "cancel/recovery" },
61 	{ SHOST_DEL_RECOVERY, "deleted/recovery", },
62 };
63 const char *scsi_host_state_name(enum scsi_host_state state)
64 {
65 	int i;
66 	char *name = NULL;
67 
68 	for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
69 		if (shost_states[i].value == state) {
70 			name = shost_states[i].name;
71 			break;
72 		}
73 	}
74 	return name;
75 }
76 
77 static int check_set(unsigned int *val, char *src)
78 {
79 	char *last;
80 
81 	if (strncmp(src, "-", 20) == 0) {
82 		*val = SCAN_WILD_CARD;
83 	} else {
84 		/*
85 		 * Doesn't check for int overflow
86 		 */
87 		*val = simple_strtoul(src, &last, 0);
88 		if (*last != '\0')
89 			return 1;
90 	}
91 	return 0;
92 }
93 
94 static int scsi_scan(struct Scsi_Host *shost, const char *str)
95 {
96 	char s1[15], s2[15], s3[15], junk;
97 	unsigned int channel, id, lun;
98 	int res;
99 
100 	res = sscanf(str, "%10s %10s %10s %c", s1, s2, s3, &junk);
101 	if (res != 3)
102 		return -EINVAL;
103 	if (check_set(&channel, s1))
104 		return -EINVAL;
105 	if (check_set(&id, s2))
106 		return -EINVAL;
107 	if (check_set(&lun, s3))
108 		return -EINVAL;
109 	if (shost->transportt->user_scan)
110 		res = shost->transportt->user_scan(shost, channel, id, lun);
111 	else
112 		res = scsi_scan_host_selected(shost, channel, id, lun, 1);
113 	return res;
114 }
115 
116 /*
117  * shost_show_function: macro to create an attr function that can be used to
118  * show a non-bit field.
119  */
120 #define shost_show_function(name, field, format_string)			\
121 static ssize_t								\
122 show_##name (struct class_device *class_dev, char *buf)			\
123 {									\
124 	struct Scsi_Host *shost = class_to_shost(class_dev);		\
125 	return snprintf (buf, 20, format_string, shost->field);		\
126 }
127 
128 /*
129  * shost_rd_attr: macro to create a function and attribute variable for a
130  * read only field.
131  */
132 #define shost_rd_attr2(name, field, format_string)			\
133 	shost_show_function(name, field, format_string)			\
134 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
135 
136 #define shost_rd_attr(field, format_string) \
137 shost_rd_attr2(field, field, format_string)
138 
139 /*
140  * Create the actual show/store functions and data structures.
141  */
142 
143 static ssize_t store_scan(struct class_device *class_dev, const char *buf,
144 			  size_t count)
145 {
146 	struct Scsi_Host *shost = class_to_shost(class_dev);
147 	int res;
148 
149 	res = scsi_scan(shost, buf);
150 	if (res == 0)
151 		res = count;
152 	return res;
153 };
154 static CLASS_DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
155 
156 static ssize_t
157 store_shost_state(struct class_device *class_dev, const char *buf, size_t count)
158 {
159 	int i;
160 	struct Scsi_Host *shost = class_to_shost(class_dev);
161 	enum scsi_host_state state = 0;
162 
163 	for (i = 0; i < ARRAY_SIZE(shost_states); i++) {
164 		const int len = strlen(shost_states[i].name);
165 		if (strncmp(shost_states[i].name, buf, len) == 0 &&
166 		   buf[len] == '\n') {
167 			state = shost_states[i].value;
168 			break;
169 		}
170 	}
171 	if (!state)
172 		return -EINVAL;
173 
174 	if (scsi_host_set_state(shost, state))
175 		return -EINVAL;
176 	return count;
177 }
178 
179 static ssize_t
180 show_shost_state(struct class_device *class_dev, char *buf)
181 {
182 	struct Scsi_Host *shost = class_to_shost(class_dev);
183 	const char *name = scsi_host_state_name(shost->shost_state);
184 
185 	if (!name)
186 		return -EINVAL;
187 
188 	return snprintf(buf, 20, "%s\n", name);
189 }
190 
191 static CLASS_DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_shost_state, store_shost_state);
192 
193 static ssize_t
194 show_shost_mode(unsigned int mode, char *buf)
195 {
196 	ssize_t len = 0;
197 
198 	if (mode & MODE_INITIATOR)
199 		len = sprintf(buf, "%s", "Initiator");
200 
201 	if (mode & MODE_TARGET)
202 		len += sprintf(buf + len, "%s%s", len ? ", " : "", "Target");
203 
204 	len += sprintf(buf + len, "\n");
205 
206 	return len;
207 }
208 
209 static ssize_t show_shost_supported_mode(struct class_device *class_dev, char *buf)
210 {
211 	struct Scsi_Host *shost = class_to_shost(class_dev);
212 	unsigned int supported_mode = shost->hostt->supported_mode;
213 
214 	if (supported_mode == MODE_UNKNOWN)
215 		/* by default this should be initiator */
216 		supported_mode = MODE_INITIATOR;
217 
218 	return show_shost_mode(supported_mode, buf);
219 }
220 
221 static CLASS_DEVICE_ATTR(supported_mode, S_IRUGO | S_IWUSR, show_shost_supported_mode, NULL);
222 
223 static ssize_t show_shost_active_mode(struct class_device *class_dev, char *buf)
224 {
225 	struct Scsi_Host *shost = class_to_shost(class_dev);
226 
227 	if (shost->active_mode == MODE_UNKNOWN)
228 		return snprintf(buf, 20, "unknown\n");
229 	else
230 		return show_shost_mode(shost->active_mode, buf);
231 }
232 
233 static CLASS_DEVICE_ATTR(active_mode, S_IRUGO | S_IWUSR, show_shost_active_mode, NULL);
234 
235 shost_rd_attr(unique_id, "%u\n");
236 shost_rd_attr(host_busy, "%hu\n");
237 shost_rd_attr(cmd_per_lun, "%hd\n");
238 shost_rd_attr(can_queue, "%hd\n");
239 shost_rd_attr(sg_tablesize, "%hu\n");
240 shost_rd_attr(unchecked_isa_dma, "%d\n");
241 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
242 
243 static struct class_device_attribute *scsi_sysfs_shost_attrs[] = {
244 	&class_device_attr_unique_id,
245 	&class_device_attr_host_busy,
246 	&class_device_attr_cmd_per_lun,
247 	&class_device_attr_can_queue,
248 	&class_device_attr_sg_tablesize,
249 	&class_device_attr_unchecked_isa_dma,
250 	&class_device_attr_proc_name,
251 	&class_device_attr_scan,
252 	&class_device_attr_state,
253 	&class_device_attr_supported_mode,
254 	&class_device_attr_active_mode,
255 	NULL
256 };
257 
258 static void scsi_device_cls_release(struct class_device *class_dev)
259 {
260 	struct scsi_device *sdev;
261 
262 	sdev = class_to_sdev(class_dev);
263 	put_device(&sdev->sdev_gendev);
264 }
265 
266 static void scsi_device_dev_release_usercontext(struct work_struct *work)
267 {
268 	struct scsi_device *sdev;
269 	struct device *parent;
270 	struct scsi_target *starget;
271 	struct list_head *this, *tmp;
272 	unsigned long flags;
273 
274 	sdev = container_of(work, struct scsi_device, ew.work);
275 
276 	parent = sdev->sdev_gendev.parent;
277 	starget = to_scsi_target(parent);
278 
279 	spin_lock_irqsave(sdev->host->host_lock, flags);
280 	starget->reap_ref++;
281 	list_del(&sdev->siblings);
282 	list_del(&sdev->same_target_siblings);
283 	list_del(&sdev->starved_entry);
284 	spin_unlock_irqrestore(sdev->host->host_lock, flags);
285 
286 	cancel_work_sync(&sdev->event_work);
287 
288 	list_for_each_safe(this, tmp, &sdev->event_list) {
289 		struct scsi_event *evt;
290 
291 		evt = list_entry(this, struct scsi_event, node);
292 		list_del(&evt->node);
293 		kfree(evt);
294 	}
295 
296 	if (sdev->request_queue) {
297 		sdev->request_queue->queuedata = NULL;
298 		/* user context needed to free queue */
299 		scsi_free_queue(sdev->request_queue);
300 		/* temporary expedient, try to catch use of queue lock
301 		 * after free of sdev */
302 		sdev->request_queue = NULL;
303 	}
304 
305 	scsi_target_reap(scsi_target(sdev));
306 
307 	kfree(sdev->inquiry);
308 	kfree(sdev);
309 
310 	if (parent)
311 		put_device(parent);
312 }
313 
314 static void scsi_device_dev_release(struct device *dev)
315 {
316 	struct scsi_device *sdp = to_scsi_device(dev);
317 	execute_in_process_context(scsi_device_dev_release_usercontext,
318 				   &sdp->ew);
319 }
320 
321 static struct class sdev_class = {
322 	.name		= "scsi_device",
323 	.release	= scsi_device_cls_release,
324 };
325 
326 /* all probing is done in the individual ->probe routines */
327 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
328 {
329 	struct scsi_device *sdp = to_scsi_device(dev);
330 	if (sdp->no_uld_attach)
331 		return 0;
332 	return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
333 }
334 
335 static int scsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
336 {
337 	struct scsi_device *sdev = to_scsi_device(dev);
338 
339 	add_uevent_var(env, "MODALIAS=" SCSI_DEVICE_MODALIAS_FMT, sdev->type);
340 	return 0;
341 }
342 
343 static int scsi_bus_suspend(struct device * dev, pm_message_t state)
344 {
345 	struct device_driver *drv = dev->driver;
346 	struct scsi_device *sdev = to_scsi_device(dev);
347 	int err;
348 
349 	err = scsi_device_quiesce(sdev);
350 	if (err)
351 		return err;
352 
353 	if (drv && drv->suspend) {
354 		err = drv->suspend(dev, state);
355 		if (err)
356 			return err;
357 	}
358 
359 	return 0;
360 }
361 
362 static int scsi_bus_resume(struct device * dev)
363 {
364 	struct device_driver *drv = dev->driver;
365 	struct scsi_device *sdev = to_scsi_device(dev);
366 	int err = 0;
367 
368 	if (drv && drv->resume)
369 		err = drv->resume(dev);
370 
371 	scsi_device_resume(sdev);
372 
373 	return err;
374 }
375 
376 struct bus_type scsi_bus_type = {
377         .name		= "scsi",
378         .match		= scsi_bus_match,
379 	.uevent		= scsi_bus_uevent,
380 	.suspend	= scsi_bus_suspend,
381 	.resume		= scsi_bus_resume,
382 };
383 
384 int scsi_sysfs_register(void)
385 {
386 	int error;
387 
388 	error = bus_register(&scsi_bus_type);
389 	if (!error) {
390 		error = class_register(&sdev_class);
391 		if (error)
392 			bus_unregister(&scsi_bus_type);
393 	}
394 
395 	return error;
396 }
397 
398 void scsi_sysfs_unregister(void)
399 {
400 	class_unregister(&sdev_class);
401 	bus_unregister(&scsi_bus_type);
402 }
403 
404 /*
405  * sdev_show_function: macro to create an attr function that can be used to
406  * show a non-bit field.
407  */
408 #define sdev_show_function(field, format_string)				\
409 static ssize_t								\
410 sdev_show_##field (struct device *dev, struct device_attribute *attr, char *buf)				\
411 {									\
412 	struct scsi_device *sdev;					\
413 	sdev = to_scsi_device(dev);					\
414 	return snprintf (buf, 20, format_string, sdev->field);		\
415 }									\
416 
417 /*
418  * sdev_rd_attr: macro to create a function and attribute variable for a
419  * read only field.
420  */
421 #define sdev_rd_attr(field, format_string)				\
422 	sdev_show_function(field, format_string)			\
423 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
424 
425 
426 /*
427  * sdev_rd_attr: create a function and attribute variable for a
428  * read/write field.
429  */
430 #define sdev_rw_attr(field, format_string)				\
431 	sdev_show_function(field, format_string)				\
432 									\
433 static ssize_t								\
434 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)	\
435 {									\
436 	struct scsi_device *sdev;					\
437 	sdev = to_scsi_device(dev);					\
438 	snscanf (buf, 20, format_string, &sdev->field);			\
439 	return count;							\
440 }									\
441 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
442 
443 /* Currently we don't export bit fields, but we might in future,
444  * so leave this code in */
445 #if 0
446 /*
447  * sdev_rd_attr: create a function and attribute variable for a
448  * read/write bit field.
449  */
450 #define sdev_rw_attr_bit(field)						\
451 	sdev_show_function(field, "%d\n")					\
452 									\
453 static ssize_t								\
454 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)	\
455 {									\
456 	int ret;							\
457 	struct scsi_device *sdev;					\
458 	ret = scsi_sdev_check_buf_bit(buf);				\
459 	if (ret >= 0)	{						\
460 		sdev = to_scsi_device(dev);				\
461 		sdev->field = ret;					\
462 		ret = count;						\
463 	}								\
464 	return ret;							\
465 }									\
466 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
467 
468 /*
469  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
470  * else return -EINVAL.
471  */
472 static int scsi_sdev_check_buf_bit(const char *buf)
473 {
474 	if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
475 		if (buf[0] == '1')
476 			return 1;
477 		else if (buf[0] == '0')
478 			return 0;
479 		else
480 			return -EINVAL;
481 	} else
482 		return -EINVAL;
483 }
484 #endif
485 /*
486  * Create the actual show/store functions and data structures.
487  */
488 sdev_rd_attr (device_blocked, "%d\n");
489 sdev_rd_attr (queue_depth, "%d\n");
490 sdev_rd_attr (type, "%d\n");
491 sdev_rd_attr (scsi_level, "%d\n");
492 sdev_rd_attr (vendor, "%.8s\n");
493 sdev_rd_attr (model, "%.16s\n");
494 sdev_rd_attr (rev, "%.4s\n");
495 
496 static ssize_t
497 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
498 {
499 	struct scsi_device *sdev;
500 	sdev = to_scsi_device(dev);
501 	return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
502 }
503 
504 static ssize_t
505 sdev_store_timeout (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
506 {
507 	struct scsi_device *sdev;
508 	int timeout;
509 	sdev = to_scsi_device(dev);
510 	sscanf (buf, "%d\n", &timeout);
511 	sdev->timeout = timeout * HZ;
512 	return count;
513 }
514 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
515 
516 static ssize_t
517 store_rescan_field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
518 {
519 	scsi_rescan_device(dev);
520 	return count;
521 }
522 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
523 
524 static void sdev_store_delete_callback(struct device *dev)
525 {
526 	scsi_remove_device(to_scsi_device(dev));
527 }
528 
529 static ssize_t sdev_store_delete(struct device *dev, struct device_attribute *attr, const char *buf,
530 				 size_t count)
531 {
532 	int rc;
533 
534 	/* An attribute cannot be unregistered by one of its own methods,
535 	 * so we have to use this roundabout approach.
536 	 */
537 	rc = device_schedule_callback(dev, sdev_store_delete_callback);
538 	if (rc)
539 		count = rc;
540 	return count;
541 };
542 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
543 
544 static ssize_t
545 store_state_field(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
546 {
547 	int i;
548 	struct scsi_device *sdev = to_scsi_device(dev);
549 	enum scsi_device_state state = 0;
550 
551 	for (i = 0; i < ARRAY_SIZE(sdev_states); i++) {
552 		const int len = strlen(sdev_states[i].name);
553 		if (strncmp(sdev_states[i].name, buf, len) == 0 &&
554 		   buf[len] == '\n') {
555 			state = sdev_states[i].value;
556 			break;
557 		}
558 	}
559 	if (!state)
560 		return -EINVAL;
561 
562 	if (scsi_device_set_state(sdev, state))
563 		return -EINVAL;
564 	return count;
565 }
566 
567 static ssize_t
568 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
569 {
570 	struct scsi_device *sdev = to_scsi_device(dev);
571 	const char *name = scsi_device_state_name(sdev->sdev_state);
572 
573 	if (!name)
574 		return -EINVAL;
575 
576 	return snprintf(buf, 20, "%s\n", name);
577 }
578 
579 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
580 
581 static ssize_t
582 show_queue_type_field(struct device *dev, struct device_attribute *attr, char *buf)
583 {
584 	struct scsi_device *sdev = to_scsi_device(dev);
585 	const char *name = "none";
586 
587 	if (sdev->ordered_tags)
588 		name = "ordered";
589 	else if (sdev->simple_tags)
590 		name = "simple";
591 
592 	return snprintf(buf, 20, "%s\n", name);
593 }
594 
595 static DEVICE_ATTR(queue_type, S_IRUGO, show_queue_type_field, NULL);
596 
597 static ssize_t
598 show_iostat_counterbits(struct device *dev, struct device_attribute *attr, char *buf)
599 {
600 	return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
601 }
602 
603 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
604 
605 #define show_sdev_iostat(field)						\
606 static ssize_t								\
607 show_iostat_##field(struct device *dev, struct device_attribute *attr, char *buf)			\
608 {									\
609 	struct scsi_device *sdev = to_scsi_device(dev);			\
610 	unsigned long long count = atomic_read(&sdev->field);		\
611 	return snprintf(buf, 20, "0x%llx\n", count);			\
612 }									\
613 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
614 
615 show_sdev_iostat(iorequest_cnt);
616 show_sdev_iostat(iodone_cnt);
617 show_sdev_iostat(ioerr_cnt);
618 
619 static ssize_t
620 sdev_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
621 {
622 	struct scsi_device *sdev;
623 	sdev = to_scsi_device(dev);
624 	return snprintf (buf, 20, SCSI_DEVICE_MODALIAS_FMT "\n", sdev->type);
625 }
626 static DEVICE_ATTR(modalias, S_IRUGO, sdev_show_modalias, NULL);
627 
628 #define DECLARE_EVT_SHOW(name, Cap_name)				\
629 static ssize_t								\
630 sdev_show_evt_##name(struct device *dev, struct device_attribute *attr,	\
631 				char *buf)				\
632 {									\
633 	struct scsi_device *sdev = to_scsi_device(dev);			\
634 	int val = test_bit(SDEV_EVT_##Cap_name, sdev->supported_events);\
635 	return snprintf(buf, 20, "%d\n", val);				\
636 }
637 
638 #define DECLARE_EVT_STORE(name, Cap_name)				\
639 static ssize_t								\
640 sdev_store_evt_##name(struct device *dev, struct device_attribute *attr, \
641 		      const char *buf, size_t count)			\
642 {									\
643 	struct scsi_device *sdev = to_scsi_device(dev);			\
644 	int val = simple_strtoul(buf, NULL, 0);				\
645 	if (val == 0)							\
646 		clear_bit(SDEV_EVT_##Cap_name, sdev->supported_events);	\
647 	else if (val == 1)						\
648 		set_bit(SDEV_EVT_##Cap_name, sdev->supported_events);	\
649 	else								\
650 		return -EINVAL;						\
651 	return count;							\
652 }
653 
654 #define DECLARE_EVT(name, Cap_name)					\
655 	DECLARE_EVT_SHOW(name, Cap_name)				\
656 	DECLARE_EVT_STORE(name, Cap_name)				\
657 	static DEVICE_ATTR(evt_##name, S_IRUGO, sdev_show_evt_##name,	\
658 			   sdev_store_evt_##name);
659 #define REF_EVT(name) &dev_attr_evt_##name.attr
660 
661 DECLARE_EVT(media_change, MEDIA_CHANGE)
662 
663 /* Default template for device attributes.  May NOT be modified */
664 static struct attribute *scsi_sdev_attrs[] = {
665 	&dev_attr_device_blocked.attr,
666 	&dev_attr_type.attr,
667 	&dev_attr_scsi_level.attr,
668 	&dev_attr_vendor.attr,
669 	&dev_attr_model.attr,
670 	&dev_attr_rev.attr,
671 	&dev_attr_rescan.attr,
672 	&dev_attr_delete.attr,
673 	&dev_attr_state.attr,
674 	&dev_attr_timeout.attr,
675 	&dev_attr_iocounterbits.attr,
676 	&dev_attr_iorequest_cnt.attr,
677 	&dev_attr_iodone_cnt.attr,
678 	&dev_attr_ioerr_cnt.attr,
679 	&dev_attr_modalias.attr,
680 	REF_EVT(media_change),
681 	NULL
682 };
683 
684 static struct attribute_group scsi_sdev_attr_group = {
685 	.attrs =	scsi_sdev_attrs,
686 };
687 
688 static struct attribute_group *scsi_sdev_attr_groups[] = {
689 	&scsi_sdev_attr_group,
690 	NULL
691 };
692 
693 static ssize_t sdev_store_queue_depth_rw(struct device *dev, struct device_attribute *attr, const char *buf,
694 					 size_t count)
695 {
696 	int depth, retval;
697 	struct scsi_device *sdev = to_scsi_device(dev);
698 	struct scsi_host_template *sht = sdev->host->hostt;
699 
700 	if (!sht->change_queue_depth)
701 		return -EINVAL;
702 
703 	depth = simple_strtoul(buf, NULL, 0);
704 
705 	if (depth < 1)
706 		return -EINVAL;
707 
708 	retval = sht->change_queue_depth(sdev, depth);
709 	if (retval < 0)
710 		return retval;
711 
712 	return count;
713 }
714 
715 static struct device_attribute sdev_attr_queue_depth_rw =
716 	__ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
717 	       sdev_store_queue_depth_rw);
718 
719 static ssize_t sdev_store_queue_type_rw(struct device *dev, struct device_attribute *attr, const char *buf,
720 					size_t count)
721 {
722 	struct scsi_device *sdev = to_scsi_device(dev);
723 	struct scsi_host_template *sht = sdev->host->hostt;
724 	int tag_type = 0, retval;
725 	int prev_tag_type = scsi_get_tag_type(sdev);
726 
727 	if (!sdev->tagged_supported || !sht->change_queue_type)
728 		return -EINVAL;
729 
730 	if (strncmp(buf, "ordered", 7) == 0)
731 		tag_type = MSG_ORDERED_TAG;
732 	else if (strncmp(buf, "simple", 6) == 0)
733 		tag_type = MSG_SIMPLE_TAG;
734 	else if (strncmp(buf, "none", 4) != 0)
735 		return -EINVAL;
736 
737 	if (tag_type == prev_tag_type)
738 		return count;
739 
740 	retval = sht->change_queue_type(sdev, tag_type);
741 	if (retval < 0)
742 		return retval;
743 
744 	return count;
745 }
746 
747 static struct device_attribute sdev_attr_queue_type_rw =
748 	__ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
749 	       sdev_store_queue_type_rw);
750 
751 /**
752  * scsi_sysfs_add_sdev - add scsi device to sysfs
753  * @sdev:	scsi_device to add
754  *
755  * Return value:
756  * 	0 on Success / non-zero on Failure
757  **/
758 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
759 {
760 	int error, i;
761 	struct request_queue *rq = sdev->request_queue;
762 
763 	if ((error = scsi_device_set_state(sdev, SDEV_RUNNING)) != 0)
764 		return error;
765 
766 	error = device_add(&sdev->sdev_gendev);
767 	if (error) {
768 		put_device(sdev->sdev_gendev.parent);
769 		printk(KERN_INFO "error 1\n");
770 		return error;
771 	}
772 	error = class_device_add(&sdev->sdev_classdev);
773 	if (error) {
774 		printk(KERN_INFO "error 2\n");
775 		goto clean_device;
776 	}
777 
778 	/* take a reference for the sdev_classdev; this is
779 	 * released by the sdev_class .release */
780 	get_device(&sdev->sdev_gendev);
781 
782 	/* create queue files, which may be writable, depending on the host */
783 	if (sdev->host->hostt->change_queue_depth)
784 		error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_depth_rw);
785 	else
786 		error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_depth);
787 	if (error) {
788 		__scsi_remove_device(sdev);
789 		goto out;
790 	}
791 	if (sdev->host->hostt->change_queue_type)
792 		error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_type_rw);
793 	else
794 		error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_type);
795 	if (error) {
796 		__scsi_remove_device(sdev);
797 		goto out;
798 	}
799 
800 	error = bsg_register_queue(rq, &sdev->sdev_gendev, NULL);
801 
802 	if (error)
803 		sdev_printk(KERN_INFO, sdev,
804 			    "Failed to register bsg queue, errno=%d\n", error);
805 
806 	/* we're treating error on bsg register as non-fatal, so pretend
807 	 * nothing went wrong */
808 	error = 0;
809 
810 	/* add additional host specific attributes */
811 	if (sdev->host->hostt->sdev_attrs) {
812 		for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
813 			error = device_create_file(&sdev->sdev_gendev,
814 					sdev->host->hostt->sdev_attrs[i]);
815 			if (error) {
816 				__scsi_remove_device(sdev);
817 				goto out;
818 			}
819 		}
820 	}
821 
822 	transport_add_device(&sdev->sdev_gendev);
823  out:
824 	return error;
825 
826  clean_device:
827 	scsi_device_set_state(sdev, SDEV_CANCEL);
828 
829 	device_del(&sdev->sdev_gendev);
830 	transport_destroy_device(&sdev->sdev_gendev);
831 	put_device(&sdev->sdev_gendev);
832 
833 	return error;
834 }
835 
836 void __scsi_remove_device(struct scsi_device *sdev)
837 {
838 	struct device *dev = &sdev->sdev_gendev;
839 
840 	if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
841 		return;
842 
843 	bsg_unregister_queue(sdev->request_queue);
844 	class_device_unregister(&sdev->sdev_classdev);
845 	transport_remove_device(dev);
846 	device_del(dev);
847 	scsi_device_set_state(sdev, SDEV_DEL);
848 	if (sdev->host->hostt->slave_destroy)
849 		sdev->host->hostt->slave_destroy(sdev);
850 	transport_destroy_device(dev);
851 	put_device(dev);
852 }
853 
854 /**
855  * scsi_remove_device - unregister a device from the scsi bus
856  * @sdev:	scsi_device to unregister
857  **/
858 void scsi_remove_device(struct scsi_device *sdev)
859 {
860 	struct Scsi_Host *shost = sdev->host;
861 
862 	mutex_lock(&shost->scan_mutex);
863 	__scsi_remove_device(sdev);
864 	mutex_unlock(&shost->scan_mutex);
865 }
866 EXPORT_SYMBOL(scsi_remove_device);
867 
868 static void __scsi_remove_target(struct scsi_target *starget)
869 {
870 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
871 	unsigned long flags;
872 	struct scsi_device *sdev;
873 
874 	spin_lock_irqsave(shost->host_lock, flags);
875 	starget->reap_ref++;
876  restart:
877 	list_for_each_entry(sdev, &shost->__devices, siblings) {
878 		if (sdev->channel != starget->channel ||
879 		    sdev->id != starget->id ||
880 		    sdev->sdev_state == SDEV_DEL)
881 			continue;
882 		spin_unlock_irqrestore(shost->host_lock, flags);
883 		scsi_remove_device(sdev);
884 		spin_lock_irqsave(shost->host_lock, flags);
885 		goto restart;
886 	}
887 	spin_unlock_irqrestore(shost->host_lock, flags);
888 	scsi_target_reap(starget);
889 }
890 
891 static int __remove_child (struct device * dev, void * data)
892 {
893 	if (scsi_is_target_device(dev))
894 		__scsi_remove_target(to_scsi_target(dev));
895 	return 0;
896 }
897 
898 /**
899  * scsi_remove_target - try to remove a target and all its devices
900  * @dev: generic starget or parent of generic stargets to be removed
901  *
902  * Note: This is slightly racy.  It is possible that if the user
903  * requests the addition of another device then the target won't be
904  * removed.
905  */
906 void scsi_remove_target(struct device *dev)
907 {
908 	struct device *rdev;
909 
910 	if (scsi_is_target_device(dev)) {
911 		__scsi_remove_target(to_scsi_target(dev));
912 		return;
913 	}
914 
915 	rdev = get_device(dev);
916 	device_for_each_child(dev, NULL, __remove_child);
917 	put_device(rdev);
918 }
919 EXPORT_SYMBOL(scsi_remove_target);
920 
921 int scsi_register_driver(struct device_driver *drv)
922 {
923 	drv->bus = &scsi_bus_type;
924 
925 	return driver_register(drv);
926 }
927 EXPORT_SYMBOL(scsi_register_driver);
928 
929 int scsi_register_interface(struct class_interface *intf)
930 {
931 	intf->class = &sdev_class;
932 
933 	return class_interface_register(intf);
934 }
935 EXPORT_SYMBOL(scsi_register_interface);
936 
937 
938 static struct class_device_attribute *class_attr_overridden(
939 		struct class_device_attribute **attrs,
940 		struct class_device_attribute *attr)
941 {
942 	int i;
943 
944 	if (!attrs)
945 		return NULL;
946 	for (i = 0; attrs[i]; i++)
947 		if (!strcmp(attrs[i]->attr.name, attr->attr.name))
948 			return attrs[i];
949 	return NULL;
950 }
951 
952 static int class_attr_add(struct class_device *classdev,
953 		struct class_device_attribute *attr)
954 {
955 	struct class_device_attribute *base_attr;
956 
957 	/*
958 	 * Spare the caller from having to copy things it's not interested in.
959 	 */
960 	base_attr = class_attr_overridden(scsi_sysfs_shost_attrs, attr);
961 	if (base_attr) {
962 		/* extend permissions */
963 		attr->attr.mode |= base_attr->attr.mode;
964 
965 		/* override null show/store with default */
966 		if (!attr->show)
967 			attr->show = base_attr->show;
968 		if (!attr->store)
969 			attr->store = base_attr->store;
970 	}
971 
972 	return class_device_create_file(classdev, attr);
973 }
974 
975 /**
976  * scsi_sysfs_add_host - add scsi host to subsystem
977  * @shost:     scsi host struct to add to subsystem
978  * @dev:       parent struct device pointer
979  **/
980 int scsi_sysfs_add_host(struct Scsi_Host *shost)
981 {
982 	int error, i;
983 
984 	if (shost->hostt->shost_attrs) {
985 		for (i = 0; shost->hostt->shost_attrs[i]; i++) {
986 			error = class_attr_add(&shost->shost_classdev,
987 					shost->hostt->shost_attrs[i]);
988 			if (error)
989 				return error;
990 		}
991 	}
992 
993 	for (i = 0; scsi_sysfs_shost_attrs[i]; i++) {
994 		if (!class_attr_overridden(shost->hostt->shost_attrs,
995 					scsi_sysfs_shost_attrs[i])) {
996 			error = class_device_create_file(&shost->shost_classdev,
997 					scsi_sysfs_shost_attrs[i]);
998 			if (error)
999 				return error;
1000 		}
1001 	}
1002 
1003 	transport_register_device(&shost->shost_gendev);
1004 	return 0;
1005 }
1006 
1007 static struct device_type scsi_dev_type = {
1008 	.name =		"scsi_device",
1009 	.release =	scsi_device_dev_release,
1010 	.groups =	scsi_sdev_attr_groups,
1011 };
1012 
1013 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
1014 {
1015 	unsigned long flags;
1016 	struct Scsi_Host *shost = sdev->host;
1017 	struct scsi_target  *starget = sdev->sdev_target;
1018 
1019 	device_initialize(&sdev->sdev_gendev);
1020 	sdev->sdev_gendev.bus = &scsi_bus_type;
1021 	sdev->sdev_gendev.type = &scsi_dev_type;
1022 	sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
1023 		sdev->host->host_no, sdev->channel, sdev->id,
1024 		sdev->lun);
1025 
1026 	class_device_initialize(&sdev->sdev_classdev);
1027 	sdev->sdev_classdev.dev = &sdev->sdev_gendev;
1028 	sdev->sdev_classdev.class = &sdev_class;
1029 	snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
1030 		 "%d:%d:%d:%d", sdev->host->host_no,
1031 		 sdev->channel, sdev->id, sdev->lun);
1032 	sdev->scsi_level = starget->scsi_level;
1033 	transport_setup_device(&sdev->sdev_gendev);
1034 	spin_lock_irqsave(shost->host_lock, flags);
1035 	list_add_tail(&sdev->same_target_siblings, &starget->devices);
1036 	list_add_tail(&sdev->siblings, &shost->__devices);
1037 	spin_unlock_irqrestore(shost->host_lock, flags);
1038 }
1039 
1040 int scsi_is_sdev_device(const struct device *dev)
1041 {
1042 	return dev->type == &scsi_dev_type;
1043 }
1044 EXPORT_SYMBOL(scsi_is_sdev_device);
1045 
1046 /* A blank transport template that is used in drivers that don't
1047  * yet implement Transport Attributes */
1048 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };
1049