xref: /linux/drivers/scsi/scsi_sysfs.c (revision 60b2737de1b1ddfdb90f3ba622634eb49d6f3603)
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/config.h>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/blkdev.h>
13 #include <linux/device.h>
14 
15 #include <scsi/scsi.h>
16 #include <scsi/scsi_device.h>
17 #include <scsi/scsi_host.h>
18 #include <scsi/scsi_tcq.h>
19 #include <scsi/scsi_transport.h>
20 
21 #include "scsi_priv.h"
22 #include "scsi_logging.h"
23 
24 static 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 < sizeof(sdev_states)/sizeof(sdev_states[0]); 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 int check_set(unsigned int *val, char *src)
52 {
53 	char *last;
54 
55 	if (strncmp(src, "-", 20) == 0) {
56 		*val = SCAN_WILD_CARD;
57 	} else {
58 		/*
59 		 * Doesn't check for int overflow
60 		 */
61 		*val = simple_strtoul(src, &last, 0);
62 		if (*last != '\0')
63 			return 1;
64 	}
65 	return 0;
66 }
67 
68 static int scsi_scan(struct Scsi_Host *shost, const char *str)
69 {
70 	char s1[15], s2[15], s3[15], junk;
71 	unsigned int channel, id, lun;
72 	int res;
73 
74 	res = sscanf(str, "%10s %10s %10s %c", s1, s2, s3, &junk);
75 	if (res != 3)
76 		return -EINVAL;
77 	if (check_set(&channel, s1))
78 		return -EINVAL;
79 	if (check_set(&id, s2))
80 		return -EINVAL;
81 	if (check_set(&lun, s3))
82 		return -EINVAL;
83 	res = scsi_scan_host_selected(shost, channel, id, lun, 1);
84 	return res;
85 }
86 
87 /*
88  * shost_show_function: macro to create an attr function that can be used to
89  * show a non-bit field.
90  */
91 #define shost_show_function(name, field, format_string)			\
92 static ssize_t								\
93 show_##name (struct class_device *class_dev, char *buf)			\
94 {									\
95 	struct Scsi_Host *shost = class_to_shost(class_dev);		\
96 	return snprintf (buf, 20, format_string, shost->field);		\
97 }
98 
99 /*
100  * shost_rd_attr: macro to create a function and attribute variable for a
101  * read only field.
102  */
103 #define shost_rd_attr2(name, field, format_string)			\
104 	shost_show_function(name, field, format_string)			\
105 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
106 
107 #define shost_rd_attr(field, format_string) \
108 shost_rd_attr2(field, field, format_string)
109 
110 /*
111  * Create the actual show/store functions and data structures.
112  */
113 
114 static ssize_t store_scan(struct class_device *class_dev, const char *buf,
115 			  size_t count)
116 {
117 	struct Scsi_Host *shost = class_to_shost(class_dev);
118 	int res;
119 
120 	res = scsi_scan(shost, buf);
121 	if (res == 0)
122 		res = count;
123 	return res;
124 };
125 static CLASS_DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
126 
127 shost_rd_attr(unique_id, "%u\n");
128 shost_rd_attr(host_busy, "%hu\n");
129 shost_rd_attr(cmd_per_lun, "%hd\n");
130 shost_rd_attr(sg_tablesize, "%hu\n");
131 shost_rd_attr(unchecked_isa_dma, "%d\n");
132 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
133 
134 static struct class_device_attribute *scsi_sysfs_shost_attrs[] = {
135 	&class_device_attr_unique_id,
136 	&class_device_attr_host_busy,
137 	&class_device_attr_cmd_per_lun,
138 	&class_device_attr_sg_tablesize,
139 	&class_device_attr_unchecked_isa_dma,
140 	&class_device_attr_proc_name,
141 	&class_device_attr_scan,
142 	NULL
143 };
144 
145 static void scsi_device_cls_release(struct class_device *class_dev)
146 {
147 	struct scsi_device *sdev;
148 
149 	sdev = class_to_sdev(class_dev);
150 	put_device(&sdev->sdev_gendev);
151 }
152 
153 void scsi_device_dev_release(struct device *dev)
154 {
155 	struct scsi_device *sdev;
156 	struct device *parent;
157 	struct scsi_target *starget;
158 	unsigned long flags;
159 
160 	parent = dev->parent;
161 	sdev = to_scsi_device(dev);
162 	starget = to_scsi_target(parent);
163 
164 	spin_lock_irqsave(sdev->host->host_lock, flags);
165 	starget->reap_ref++;
166 	list_del(&sdev->siblings);
167 	list_del(&sdev->same_target_siblings);
168 	list_del(&sdev->starved_entry);
169 	spin_unlock_irqrestore(sdev->host->host_lock, flags);
170 
171 	if (sdev->request_queue) {
172 		sdev->request_queue->queuedata = NULL;
173 		scsi_free_queue(sdev->request_queue);
174 		/* temporary expedient, try to catch use of queue lock
175 		 * after free of sdev */
176 		sdev->request_queue = NULL;
177 	}
178 
179 	scsi_target_reap(scsi_target(sdev));
180 
181 	kfree(sdev->inquiry);
182 	kfree(sdev);
183 
184 	if (parent)
185 		put_device(parent);
186 }
187 
188 struct class sdev_class = {
189 	.name		= "scsi_device",
190 	.release	= scsi_device_cls_release,
191 };
192 
193 /* all probing is done in the individual ->probe routines */
194 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
195 {
196 	struct scsi_device *sdp = to_scsi_device(dev);
197 	if (sdp->no_uld_attach)
198 		return 0;
199 	return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
200 }
201 
202 struct bus_type scsi_bus_type = {
203         .name		= "scsi",
204         .match		= scsi_bus_match,
205 };
206 
207 int scsi_sysfs_register(void)
208 {
209 	int error;
210 
211 	error = bus_register(&scsi_bus_type);
212 	if (!error) {
213 		error = class_register(&sdev_class);
214 		if (error)
215 			bus_unregister(&scsi_bus_type);
216 	}
217 
218 	return error;
219 }
220 
221 void scsi_sysfs_unregister(void)
222 {
223 	class_unregister(&sdev_class);
224 	bus_unregister(&scsi_bus_type);
225 }
226 
227 /*
228  * sdev_show_function: macro to create an attr function that can be used to
229  * show a non-bit field.
230  */
231 #define sdev_show_function(field, format_string)				\
232 static ssize_t								\
233 sdev_show_##field (struct device *dev, struct device_attribute *attr, char *buf)				\
234 {									\
235 	struct scsi_device *sdev;					\
236 	sdev = to_scsi_device(dev);					\
237 	return snprintf (buf, 20, format_string, sdev->field);		\
238 }									\
239 
240 /*
241  * sdev_rd_attr: macro to create a function and attribute variable for a
242  * read only field.
243  */
244 #define sdev_rd_attr(field, format_string)				\
245 	sdev_show_function(field, format_string)			\
246 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
247 
248 
249 /*
250  * sdev_rd_attr: create a function and attribute variable for a
251  * read/write field.
252  */
253 #define sdev_rw_attr(field, format_string)				\
254 	sdev_show_function(field, format_string)				\
255 									\
256 static ssize_t								\
257 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)	\
258 {									\
259 	struct scsi_device *sdev;					\
260 	sdev = to_scsi_device(dev);					\
261 	snscanf (buf, 20, format_string, &sdev->field);			\
262 	return count;							\
263 }									\
264 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
265 
266 /* Currently we don't export bit fields, but we might in future,
267  * so leave this code in */
268 #if 0
269 /*
270  * sdev_rd_attr: create a function and attribute variable for a
271  * read/write bit field.
272  */
273 #define sdev_rw_attr_bit(field)						\
274 	sdev_show_function(field, "%d\n")					\
275 									\
276 static ssize_t								\
277 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)	\
278 {									\
279 	int ret;							\
280 	struct scsi_device *sdev;					\
281 	ret = scsi_sdev_check_buf_bit(buf);				\
282 	if (ret >= 0)	{						\
283 		sdev = to_scsi_device(dev);				\
284 		sdev->field = ret;					\
285 		ret = count;						\
286 	}								\
287 	return ret;							\
288 }									\
289 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
290 
291 /*
292  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
293  * else return -EINVAL.
294  */
295 static int scsi_sdev_check_buf_bit(const char *buf)
296 {
297 	if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
298 		if (buf[0] == '1')
299 			return 1;
300 		else if (buf[0] == '0')
301 			return 0;
302 		else
303 			return -EINVAL;
304 	} else
305 		return -EINVAL;
306 }
307 #endif
308 /*
309  * Create the actual show/store functions and data structures.
310  */
311 sdev_rd_attr (device_blocked, "%d\n");
312 sdev_rd_attr (queue_depth, "%d\n");
313 sdev_rd_attr (type, "%d\n");
314 sdev_rd_attr (scsi_level, "%d\n");
315 sdev_rd_attr (vendor, "%.8s\n");
316 sdev_rd_attr (model, "%.16s\n");
317 sdev_rd_attr (rev, "%.4s\n");
318 
319 static ssize_t
320 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
321 {
322 	struct scsi_device *sdev;
323 	sdev = to_scsi_device(dev);
324 	return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
325 }
326 
327 static ssize_t
328 sdev_store_timeout (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
329 {
330 	struct scsi_device *sdev;
331 	int timeout;
332 	sdev = to_scsi_device(dev);
333 	sscanf (buf, "%d\n", &timeout);
334 	sdev->timeout = timeout * HZ;
335 	return count;
336 }
337 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
338 
339 static ssize_t
340 store_rescan_field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
341 {
342 	scsi_rescan_device(dev);
343 	return count;
344 }
345 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
346 
347 static ssize_t sdev_store_delete(struct device *dev, struct device_attribute *attr, const char *buf,
348 				 size_t count)
349 {
350 	scsi_remove_device(to_scsi_device(dev));
351 	return count;
352 };
353 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
354 
355 static ssize_t
356 store_state_field(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
357 {
358 	int i;
359 	struct scsi_device *sdev = to_scsi_device(dev);
360 	enum scsi_device_state state = 0;
361 
362 	for (i = 0; i < sizeof(sdev_states)/sizeof(sdev_states[0]); i++) {
363 		const int len = strlen(sdev_states[i].name);
364 		if (strncmp(sdev_states[i].name, buf, len) == 0 &&
365 		   buf[len] == '\n') {
366 			state = sdev_states[i].value;
367 			break;
368 		}
369 	}
370 	if (!state)
371 		return -EINVAL;
372 
373 	if (scsi_device_set_state(sdev, state))
374 		return -EINVAL;
375 	return count;
376 }
377 
378 static ssize_t
379 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
380 {
381 	struct scsi_device *sdev = to_scsi_device(dev);
382 	const char *name = scsi_device_state_name(sdev->sdev_state);
383 
384 	if (!name)
385 		return -EINVAL;
386 
387 	return snprintf(buf, 20, "%s\n", name);
388 }
389 
390 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
391 
392 static ssize_t
393 show_queue_type_field(struct device *dev, struct device_attribute *attr, char *buf)
394 {
395 	struct scsi_device *sdev = to_scsi_device(dev);
396 	const char *name = "none";
397 
398 	if (sdev->ordered_tags)
399 		name = "ordered";
400 	else if (sdev->simple_tags)
401 		name = "simple";
402 
403 	return snprintf(buf, 20, "%s\n", name);
404 }
405 
406 static DEVICE_ATTR(queue_type, S_IRUGO, show_queue_type_field, NULL);
407 
408 static ssize_t
409 show_iostat_counterbits(struct device *dev, struct device_attribute *attr, char *buf)
410 {
411 	return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
412 }
413 
414 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
415 
416 #define show_sdev_iostat(field)						\
417 static ssize_t								\
418 show_iostat_##field(struct device *dev, struct device_attribute *attr, char *buf)			\
419 {									\
420 	struct scsi_device *sdev = to_scsi_device(dev);			\
421 	unsigned long long count = atomic_read(&sdev->field);		\
422 	return snprintf(buf, 20, "0x%llx\n", count);			\
423 }									\
424 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
425 
426 show_sdev_iostat(iorequest_cnt);
427 show_sdev_iostat(iodone_cnt);
428 show_sdev_iostat(ioerr_cnt);
429 
430 
431 /* Default template for device attributes.  May NOT be modified */
432 static struct device_attribute *scsi_sysfs_sdev_attrs[] = {
433 	&dev_attr_device_blocked,
434 	&dev_attr_queue_depth,
435 	&dev_attr_queue_type,
436 	&dev_attr_type,
437 	&dev_attr_scsi_level,
438 	&dev_attr_vendor,
439 	&dev_attr_model,
440 	&dev_attr_rev,
441 	&dev_attr_rescan,
442 	&dev_attr_delete,
443 	&dev_attr_state,
444 	&dev_attr_timeout,
445 	&dev_attr_iocounterbits,
446 	&dev_attr_iorequest_cnt,
447 	&dev_attr_iodone_cnt,
448 	&dev_attr_ioerr_cnt,
449 	NULL
450 };
451 
452 static ssize_t sdev_store_queue_depth_rw(struct device *dev, struct device_attribute *attr, const char *buf,
453 					 size_t count)
454 {
455 	int depth, retval;
456 	struct scsi_device *sdev = to_scsi_device(dev);
457 	struct scsi_host_template *sht = sdev->host->hostt;
458 
459 	if (!sht->change_queue_depth)
460 		return -EINVAL;
461 
462 	depth = simple_strtoul(buf, NULL, 0);
463 
464 	if (depth < 1)
465 		return -EINVAL;
466 
467 	retval = sht->change_queue_depth(sdev, depth);
468 	if (retval < 0)
469 		return retval;
470 
471 	return count;
472 }
473 
474 static struct device_attribute sdev_attr_queue_depth_rw =
475 	__ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
476 	       sdev_store_queue_depth_rw);
477 
478 static ssize_t sdev_store_queue_type_rw(struct device *dev, struct device_attribute *attr, const char *buf,
479 					size_t count)
480 {
481 	struct scsi_device *sdev = to_scsi_device(dev);
482 	struct scsi_host_template *sht = sdev->host->hostt;
483 	int tag_type = 0, retval;
484 	int prev_tag_type = scsi_get_tag_type(sdev);
485 
486 	if (!sdev->tagged_supported || !sht->change_queue_type)
487 		return -EINVAL;
488 
489 	if (strncmp(buf, "ordered", 7) == 0)
490 		tag_type = MSG_ORDERED_TAG;
491 	else if (strncmp(buf, "simple", 6) == 0)
492 		tag_type = MSG_SIMPLE_TAG;
493 	else if (strncmp(buf, "none", 4) != 0)
494 		return -EINVAL;
495 
496 	if (tag_type == prev_tag_type)
497 		return count;
498 
499 	retval = sht->change_queue_type(sdev, tag_type);
500 	if (retval < 0)
501 		return retval;
502 
503 	return count;
504 }
505 
506 static struct device_attribute sdev_attr_queue_type_rw =
507 	__ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
508 	       sdev_store_queue_type_rw);
509 
510 static struct device_attribute *attr_changed_internally(
511 		struct Scsi_Host *shost,
512 		struct device_attribute * attr)
513 {
514 	if (!strcmp("queue_depth", attr->attr.name)
515 	    && shost->hostt->change_queue_depth)
516 		return &sdev_attr_queue_depth_rw;
517 	else if (!strcmp("queue_type", attr->attr.name)
518 	    && shost->hostt->change_queue_type)
519 		return &sdev_attr_queue_type_rw;
520 	return attr;
521 }
522 
523 
524 static struct device_attribute *attr_overridden(
525 		struct device_attribute **attrs,
526 		struct device_attribute *attr)
527 {
528 	int i;
529 
530 	if (!attrs)
531 		return NULL;
532 	for (i = 0; attrs[i]; i++)
533 		if (!strcmp(attrs[i]->attr.name, attr->attr.name))
534 			return attrs[i];
535 	return NULL;
536 }
537 
538 static int attr_add(struct device *dev, struct device_attribute *attr)
539 {
540 	struct device_attribute *base_attr;
541 
542 	/*
543 	 * Spare the caller from having to copy things it's not interested in.
544 	 */
545 	base_attr = attr_overridden(scsi_sysfs_sdev_attrs, attr);
546 	if (base_attr) {
547 		/* extend permissions */
548 		attr->attr.mode |= base_attr->attr.mode;
549 
550 		/* override null show/store with default */
551 		if (!attr->show)
552 			attr->show = base_attr->show;
553 		if (!attr->store)
554 			attr->store = base_attr->store;
555 	}
556 
557 	return device_create_file(dev, attr);
558 }
559 
560 /**
561  * scsi_sysfs_add_sdev - add scsi device to sysfs
562  * @sdev:	scsi_device to add
563  *
564  * Return value:
565  * 	0 on Success / non-zero on Failure
566  **/
567 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
568 {
569 	int error, i;
570 
571 	if ((error = scsi_device_set_state(sdev, SDEV_RUNNING)) != 0)
572 		return error;
573 
574 	error = device_add(&sdev->sdev_gendev);
575 	if (error) {
576 		put_device(sdev->sdev_gendev.parent);
577 		printk(KERN_INFO "error 1\n");
578 		return error;
579 	}
580 	error = class_device_add(&sdev->sdev_classdev);
581 	if (error) {
582 		printk(KERN_INFO "error 2\n");
583 		goto clean_device;
584 	}
585 
586 	/* take a reference for the sdev_classdev; this is
587 	 * released by the sdev_class .release */
588 	get_device(&sdev->sdev_gendev);
589 	if (sdev->host->hostt->sdev_attrs) {
590 		for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
591 			error = attr_add(&sdev->sdev_gendev,
592 					sdev->host->hostt->sdev_attrs[i]);
593 			if (error) {
594 				scsi_remove_device(sdev);
595 				goto out;
596 			}
597 		}
598 	}
599 
600 	for (i = 0; scsi_sysfs_sdev_attrs[i]; i++) {
601 		if (!attr_overridden(sdev->host->hostt->sdev_attrs,
602 					scsi_sysfs_sdev_attrs[i])) {
603 			struct device_attribute * attr =
604 				attr_changed_internally(sdev->host,
605 							scsi_sysfs_sdev_attrs[i]);
606 			error = device_create_file(&sdev->sdev_gendev, attr);
607 			if (error) {
608 				scsi_remove_device(sdev);
609 				goto out;
610 			}
611 		}
612 	}
613 
614 	transport_add_device(&sdev->sdev_gendev);
615  out:
616 	return error;
617 
618  clean_device:
619 	scsi_device_set_state(sdev, SDEV_CANCEL);
620 
621 	device_del(&sdev->sdev_gendev);
622 	transport_destroy_device(&sdev->sdev_gendev);
623 	put_device(&sdev->sdev_gendev);
624 
625 	return error;
626 }
627 
628 /**
629  * scsi_remove_device - unregister a device from the scsi bus
630  * @sdev:	scsi_device to unregister
631  **/
632 void scsi_remove_device(struct scsi_device *sdev)
633 {
634 	struct Scsi_Host *shost = sdev->host;
635 
636 	down(&shost->scan_mutex);
637 	if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
638 		goto out;
639 
640 	class_device_unregister(&sdev->sdev_classdev);
641 	device_del(&sdev->sdev_gendev);
642 	scsi_device_set_state(sdev, SDEV_DEL);
643 	if (sdev->host->hostt->slave_destroy)
644 		sdev->host->hostt->slave_destroy(sdev);
645 	transport_unregister_device(&sdev->sdev_gendev);
646 	put_device(&sdev->sdev_gendev);
647 out:
648 	up(&shost->scan_mutex);
649 }
650 EXPORT_SYMBOL(scsi_remove_device);
651 
652 void __scsi_remove_target(struct scsi_target *starget)
653 {
654 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
655 	unsigned long flags;
656 	struct scsi_device *sdev, *tmp;
657 
658 	spin_lock_irqsave(shost->host_lock, flags);
659 	starget->reap_ref++;
660 	list_for_each_entry_safe(sdev, tmp, &shost->__devices, siblings) {
661 		if (sdev->channel != starget->channel ||
662 		    sdev->id != starget->id)
663 			continue;
664 		spin_unlock_irqrestore(shost->host_lock, flags);
665 		scsi_remove_device(sdev);
666 		spin_lock_irqsave(shost->host_lock, flags);
667 	}
668 	spin_unlock_irqrestore(shost->host_lock, flags);
669 	scsi_target_reap(starget);
670 }
671 
672 static int __remove_child (struct device * dev, void * data)
673 {
674 	if (scsi_is_target_device(dev))
675 		__scsi_remove_target(to_scsi_target(dev));
676 	return 0;
677 }
678 
679 /**
680  * scsi_remove_target - try to remove a target and all its devices
681  * @dev: generic starget or parent of generic stargets to be removed
682  *
683  * Note: This is slightly racy.  It is possible that if the user
684  * requests the addition of another device then the target won't be
685  * removed.
686  */
687 void scsi_remove_target(struct device *dev)
688 {
689 	struct device *rdev;
690 
691 	if (scsi_is_target_device(dev)) {
692 		__scsi_remove_target(to_scsi_target(dev));
693 		return;
694 	}
695 
696 	rdev = get_device(dev);
697 	device_for_each_child(dev, NULL, __remove_child);
698 	put_device(rdev);
699 }
700 EXPORT_SYMBOL(scsi_remove_target);
701 
702 int scsi_register_driver(struct device_driver *drv)
703 {
704 	drv->bus = &scsi_bus_type;
705 
706 	return driver_register(drv);
707 }
708 EXPORT_SYMBOL(scsi_register_driver);
709 
710 int scsi_register_interface(struct class_interface *intf)
711 {
712 	intf->class = &sdev_class;
713 
714 	return class_interface_register(intf);
715 }
716 EXPORT_SYMBOL(scsi_register_interface);
717 
718 
719 static struct class_device_attribute *class_attr_overridden(
720 		struct class_device_attribute **attrs,
721 		struct class_device_attribute *attr)
722 {
723 	int i;
724 
725 	if (!attrs)
726 		return NULL;
727 	for (i = 0; attrs[i]; i++)
728 		if (!strcmp(attrs[i]->attr.name, attr->attr.name))
729 			return attrs[i];
730 	return NULL;
731 }
732 
733 static int class_attr_add(struct class_device *classdev,
734 		struct class_device_attribute *attr)
735 {
736 	struct class_device_attribute *base_attr;
737 
738 	/*
739 	 * Spare the caller from having to copy things it's not interested in.
740 	 */
741 	base_attr = class_attr_overridden(scsi_sysfs_shost_attrs, attr);
742 	if (base_attr) {
743 		/* extend permissions */
744 		attr->attr.mode |= base_attr->attr.mode;
745 
746 		/* override null show/store with default */
747 		if (!attr->show)
748 			attr->show = base_attr->show;
749 		if (!attr->store)
750 			attr->store = base_attr->store;
751 	}
752 
753 	return class_device_create_file(classdev, attr);
754 }
755 
756 /**
757  * scsi_sysfs_add_host - add scsi host to subsystem
758  * @shost:     scsi host struct to add to subsystem
759  * @dev:       parent struct device pointer
760  **/
761 int scsi_sysfs_add_host(struct Scsi_Host *shost)
762 {
763 	int error, i;
764 
765 	if (shost->hostt->shost_attrs) {
766 		for (i = 0; shost->hostt->shost_attrs[i]; i++) {
767 			error = class_attr_add(&shost->shost_classdev,
768 					shost->hostt->shost_attrs[i]);
769 			if (error)
770 				return error;
771 		}
772 	}
773 
774 	for (i = 0; scsi_sysfs_shost_attrs[i]; i++) {
775 		if (!class_attr_overridden(shost->hostt->shost_attrs,
776 					scsi_sysfs_shost_attrs[i])) {
777 			error = class_device_create_file(&shost->shost_classdev,
778 					scsi_sysfs_shost_attrs[i]);
779 			if (error)
780 				return error;
781 		}
782 	}
783 
784 	transport_register_device(&shost->shost_gendev);
785 	return 0;
786 }
787 
788 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
789 {
790 	unsigned long flags;
791 	struct Scsi_Host *shost = sdev->host;
792 	struct scsi_target  *starget = sdev->sdev_target;
793 
794 	device_initialize(&sdev->sdev_gendev);
795 	sdev->sdev_gendev.bus = &scsi_bus_type;
796 	sdev->sdev_gendev.release = scsi_device_dev_release;
797 	sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
798 		sdev->host->host_no, sdev->channel, sdev->id,
799 		sdev->lun);
800 
801 	class_device_initialize(&sdev->sdev_classdev);
802 	sdev->sdev_classdev.dev = &sdev->sdev_gendev;
803 	sdev->sdev_classdev.class = &sdev_class;
804 	snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
805 		 "%d:%d:%d:%d", sdev->host->host_no,
806 		 sdev->channel, sdev->id, sdev->lun);
807 	sdev->scsi_level = SCSI_2;
808 	transport_setup_device(&sdev->sdev_gendev);
809 	spin_lock_irqsave(shost->host_lock, flags);
810 	list_add_tail(&sdev->same_target_siblings, &starget->devices);
811 	list_add_tail(&sdev->siblings, &shost->__devices);
812 	spin_unlock_irqrestore(shost->host_lock, flags);
813 }
814 
815 int scsi_is_sdev_device(const struct device *dev)
816 {
817 	return dev->release == scsi_device_dev_release;
818 }
819 EXPORT_SYMBOL(scsi_is_sdev_device);
820 
821 /* A blank transport template that is used in drivers that don't
822  * yet implement Transport Attributes */
823 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };
824