[SCSI] fix scsi process problems and clean up the target reap issues
[linux-2.6.git] / drivers / scsi / scsi_sysfs.c
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 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 < 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 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 < sizeof(shost_states)/sizeof(shost_states[0]); 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 < sizeof(shost_states)/sizeof(shost_states[0]); 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 shost_rd_attr(unique_id, "%u\n");
194 shost_rd_attr(host_busy, "%hu\n");
195 shost_rd_attr(cmd_per_lun, "%hd\n");
196 shost_rd_attr(sg_tablesize, "%hu\n");
197 shost_rd_attr(unchecked_isa_dma, "%d\n");
198 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
199
200 static struct class_device_attribute *scsi_sysfs_shost_attrs[] = {
201         &class_device_attr_unique_id,
202         &class_device_attr_host_busy,
203         &class_device_attr_cmd_per_lun,
204         &class_device_attr_sg_tablesize,
205         &class_device_attr_unchecked_isa_dma,
206         &class_device_attr_proc_name,
207         &class_device_attr_scan,
208         &class_device_attr_state,
209         NULL
210 };
211
212 static void scsi_device_cls_release(struct class_device *class_dev)
213 {
214         struct scsi_device *sdev;
215
216         sdev = class_to_sdev(class_dev);
217         put_device(&sdev->sdev_gendev);
218 }
219
220 static void scsi_device_dev_release_usercontext(void *data)
221 {
222         struct device *dev = data;
223         struct scsi_device *sdev;
224         struct device *parent;
225         struct scsi_target *starget;
226         unsigned long flags;
227
228         parent = dev->parent;
229         sdev = to_scsi_device(dev);
230         starget = to_scsi_target(parent);
231
232         spin_lock_irqsave(sdev->host->host_lock, flags);
233         starget->reap_ref++;
234         list_del(&sdev->siblings);
235         list_del(&sdev->same_target_siblings);
236         list_del(&sdev->starved_entry);
237         spin_unlock_irqrestore(sdev->host->host_lock, flags);
238
239         if (sdev->request_queue) {
240                 sdev->request_queue->queuedata = NULL;
241                 /* user context needed to free queue */
242                 scsi_free_queue(sdev->request_queue);
243                 /* temporary expedient, try to catch use of queue lock
244                  * after free of sdev */
245                 sdev->request_queue = NULL;
246         }
247
248         scsi_target_reap(scsi_target(sdev));
249
250         kfree(sdev->inquiry);
251         kfree(sdev);
252
253         if (parent)
254                 put_device(parent);
255 }
256
257 static void scsi_device_dev_release(struct device *dev)
258 {
259         struct scsi_device *sdp = to_scsi_device(dev);
260         execute_in_process_context(scsi_device_dev_release_usercontext, dev,
261                                    &sdp->ew);
262 }
263
264 static struct class sdev_class = {
265         .name           = "scsi_device",
266         .release        = scsi_device_cls_release,
267 };
268
269 /* all probing is done in the individual ->probe routines */
270 static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
271 {
272         struct scsi_device *sdp = to_scsi_device(dev);
273         if (sdp->no_uld_attach)
274                 return 0;
275         return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
276 }
277
278 static int scsi_bus_suspend(struct device * dev, pm_message_t state)
279 {
280         struct scsi_device *sdev = to_scsi_device(dev);
281         struct scsi_host_template *sht = sdev->host->hostt;
282         int err;
283
284         err = scsi_device_quiesce(sdev);
285         if (err)
286                 return err;
287
288         if (sht->suspend)
289                 err = sht->suspend(sdev);
290
291         return err;
292 }
293
294 static int scsi_bus_resume(struct device * dev)
295 {
296         struct scsi_device *sdev = to_scsi_device(dev);
297         struct scsi_host_template *sht = sdev->host->hostt;
298         int err = 0;
299
300         if (sht->resume)
301                 err = sht->resume(sdev);
302
303         scsi_device_resume(sdev);
304         return err;
305 }
306
307 struct bus_type scsi_bus_type = {
308         .name           = "scsi",
309         .match          = scsi_bus_match,
310         .suspend        = scsi_bus_suspend,
311         .resume         = scsi_bus_resume,
312 };
313
314 int scsi_sysfs_register(void)
315 {
316         int error;
317
318         error = bus_register(&scsi_bus_type);
319         if (!error) {
320                 error = class_register(&sdev_class);
321                 if (error)
322                         bus_unregister(&scsi_bus_type);
323         }
324
325         return error;
326 }
327
328 void scsi_sysfs_unregister(void)
329 {
330         class_unregister(&sdev_class);
331         bus_unregister(&scsi_bus_type);
332 }
333
334 /*
335  * sdev_show_function: macro to create an attr function that can be used to
336  * show a non-bit field.
337  */
338 #define sdev_show_function(field, format_string)                                \
339 static ssize_t                                                          \
340 sdev_show_##field (struct device *dev, struct device_attribute *attr, char *buf)                                \
341 {                                                                       \
342         struct scsi_device *sdev;                                       \
343         sdev = to_scsi_device(dev);                                     \
344         return snprintf (buf, 20, format_string, sdev->field);          \
345 }                                                                       \
346
347 /*
348  * sdev_rd_attr: macro to create a function and attribute variable for a
349  * read only field.
350  */
351 #define sdev_rd_attr(field, format_string)                              \
352         sdev_show_function(field, format_string)                        \
353 static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
354
355
356 /*
357  * sdev_rd_attr: create a function and attribute variable for a
358  * read/write field.
359  */
360 #define sdev_rw_attr(field, format_string)                              \
361         sdev_show_function(field, format_string)                                \
362                                                                         \
363 static ssize_t                                                          \
364 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)   \
365 {                                                                       \
366         struct scsi_device *sdev;                                       \
367         sdev = to_scsi_device(dev);                                     \
368         snscanf (buf, 20, format_string, &sdev->field);                 \
369         return count;                                                   \
370 }                                                                       \
371 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
372
373 /* Currently we don't export bit fields, but we might in future,
374  * so leave this code in */
375 #if 0
376 /*
377  * sdev_rd_attr: create a function and attribute variable for a
378  * read/write bit field.
379  */
380 #define sdev_rw_attr_bit(field)                                         \
381         sdev_show_function(field, "%d\n")                                       \
382                                                                         \
383 static ssize_t                                                          \
384 sdev_store_##field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)   \
385 {                                                                       \
386         int ret;                                                        \
387         struct scsi_device *sdev;                                       \
388         ret = scsi_sdev_check_buf_bit(buf);                             \
389         if (ret >= 0)   {                                               \
390                 sdev = to_scsi_device(dev);                             \
391                 sdev->field = ret;                                      \
392                 ret = count;                                            \
393         }                                                               \
394         return ret;                                                     \
395 }                                                                       \
396 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
397
398 /*
399  * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
400  * else return -EINVAL.
401  */
402 static int scsi_sdev_check_buf_bit(const char *buf)
403 {
404         if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
405                 if (buf[0] == '1')
406                         return 1;
407                 else if (buf[0] == '0')
408                         return 0;
409                 else 
410                         return -EINVAL;
411         } else
412                 return -EINVAL;
413 }
414 #endif
415 /*
416  * Create the actual show/store functions and data structures.
417  */
418 sdev_rd_attr (device_blocked, "%d\n");
419 sdev_rd_attr (queue_depth, "%d\n");
420 sdev_rd_attr (type, "%d\n");
421 sdev_rd_attr (scsi_level, "%d\n");
422 sdev_rd_attr (vendor, "%.8s\n");
423 sdev_rd_attr (model, "%.16s\n");
424 sdev_rd_attr (rev, "%.4s\n");
425
426 static ssize_t
427 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
428 {
429         struct scsi_device *sdev;
430         sdev = to_scsi_device(dev);
431         return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
432 }
433
434 static ssize_t
435 sdev_store_timeout (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
436 {
437         struct scsi_device *sdev;
438         int timeout;
439         sdev = to_scsi_device(dev);
440         sscanf (buf, "%d\n", &timeout);
441         sdev->timeout = timeout * HZ;
442         return count;
443 }
444 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
445
446 static ssize_t
447 store_rescan_field (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
448 {
449         scsi_rescan_device(dev);
450         return count;
451 }
452 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
453
454 static ssize_t sdev_store_delete(struct device *dev, struct device_attribute *attr, const char *buf,
455                                  size_t count)
456 {
457         scsi_remove_device(to_scsi_device(dev));
458         return count;
459 };
460 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
461
462 static ssize_t
463 store_state_field(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
464 {
465         int i;
466         struct scsi_device *sdev = to_scsi_device(dev);
467         enum scsi_device_state state = 0;
468
469         for (i = 0; i < sizeof(sdev_states)/sizeof(sdev_states[0]); i++) {
470                 const int len = strlen(sdev_states[i].name);
471                 if (strncmp(sdev_states[i].name, buf, len) == 0 &&
472                    buf[len] == '\n') {
473                         state = sdev_states[i].value;
474                         break;
475                 }
476         }
477         if (!state)
478                 return -EINVAL;
479
480         if (scsi_device_set_state(sdev, state))
481                 return -EINVAL;
482         return count;
483 }
484
485 static ssize_t
486 show_state_field(struct device *dev, struct device_attribute *attr, char *buf)
487 {
488         struct scsi_device *sdev = to_scsi_device(dev);
489         const char *name = scsi_device_state_name(sdev->sdev_state);
490
491         if (!name)
492                 return -EINVAL;
493
494         return snprintf(buf, 20, "%s\n", name);
495 }
496
497 static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
498
499 static ssize_t
500 show_queue_type_field(struct device *dev, struct device_attribute *attr, char *buf)
501 {
502         struct scsi_device *sdev = to_scsi_device(dev);
503         const char *name = "none";
504
505         if (sdev->ordered_tags)
506                 name = "ordered";
507         else if (sdev->simple_tags)
508                 name = "simple";
509
510         return snprintf(buf, 20, "%s\n", name);
511 }
512
513 static DEVICE_ATTR(queue_type, S_IRUGO, show_queue_type_field, NULL);
514
515 static ssize_t
516 show_iostat_counterbits(struct device *dev, struct device_attribute *attr, char *buf)
517 {
518         return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
519 }
520
521 static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
522
523 #define show_sdev_iostat(field)                                         \
524 static ssize_t                                                          \
525 show_iostat_##field(struct device *dev, struct device_attribute *attr, char *buf)                       \
526 {                                                                       \
527         struct scsi_device *sdev = to_scsi_device(dev);                 \
528         unsigned long long count = atomic_read(&sdev->field);           \
529         return snprintf(buf, 20, "0x%llx\n", count);                    \
530 }                                                                       \
531 static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
532
533 show_sdev_iostat(iorequest_cnt);
534 show_sdev_iostat(iodone_cnt);
535 show_sdev_iostat(ioerr_cnt);
536
537
538 /* Default template for device attributes.  May NOT be modified */
539 static struct device_attribute *scsi_sysfs_sdev_attrs[] = {
540         &dev_attr_device_blocked,
541         &dev_attr_queue_depth,
542         &dev_attr_queue_type,
543         &dev_attr_type,
544         &dev_attr_scsi_level,
545         &dev_attr_vendor,
546         &dev_attr_model,
547         &dev_attr_rev,
548         &dev_attr_rescan,
549         &dev_attr_delete,
550         &dev_attr_state,
551         &dev_attr_timeout,
552         &dev_attr_iocounterbits,
553         &dev_attr_iorequest_cnt,
554         &dev_attr_iodone_cnt,
555         &dev_attr_ioerr_cnt,
556         NULL
557 };
558
559 static ssize_t sdev_store_queue_depth_rw(struct device *dev, struct device_attribute *attr, const char *buf,
560                                          size_t count)
561 {
562         int depth, retval;
563         struct scsi_device *sdev = to_scsi_device(dev);
564         struct scsi_host_template *sht = sdev->host->hostt;
565
566         if (!sht->change_queue_depth)
567                 return -EINVAL;
568
569         depth = simple_strtoul(buf, NULL, 0);
570
571         if (depth < 1)
572                 return -EINVAL;
573
574         retval = sht->change_queue_depth(sdev, depth);
575         if (retval < 0)
576                 return retval;
577
578         return count;
579 }
580
581 static struct device_attribute sdev_attr_queue_depth_rw =
582         __ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
583                sdev_store_queue_depth_rw);
584
585 static ssize_t sdev_store_queue_type_rw(struct device *dev, struct device_attribute *attr, const char *buf,
586                                         size_t count)
587 {
588         struct scsi_device *sdev = to_scsi_device(dev);
589         struct scsi_host_template *sht = sdev->host->hostt;
590         int tag_type = 0, retval;
591         int prev_tag_type = scsi_get_tag_type(sdev);
592
593         if (!sdev->tagged_supported || !sht->change_queue_type)
594                 return -EINVAL;
595
596         if (strncmp(buf, "ordered", 7) == 0)
597                 tag_type = MSG_ORDERED_TAG;
598         else if (strncmp(buf, "simple", 6) == 0)
599                 tag_type = MSG_SIMPLE_TAG;
600         else if (strncmp(buf, "none", 4) != 0)
601                 return -EINVAL;
602
603         if (tag_type == prev_tag_type)
604                 return count;
605
606         retval = sht->change_queue_type(sdev, tag_type);
607         if (retval < 0)
608                 return retval;
609
610         return count;
611 }
612
613 static struct device_attribute sdev_attr_queue_type_rw =
614         __ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
615                sdev_store_queue_type_rw);
616
617 static struct device_attribute *attr_changed_internally(
618                 struct Scsi_Host *shost,
619                 struct device_attribute * attr)
620 {
621         if (!strcmp("queue_depth", attr->attr.name)
622             && shost->hostt->change_queue_depth)
623                 return &sdev_attr_queue_depth_rw;
624         else if (!strcmp("queue_type", attr->attr.name)
625             && shost->hostt->change_queue_type)
626                 return &sdev_attr_queue_type_rw;
627         return attr;
628 }
629
630
631 static struct device_attribute *attr_overridden(
632                 struct device_attribute **attrs,
633                 struct device_attribute *attr)
634 {
635         int i;
636
637         if (!attrs)
638                 return NULL;
639         for (i = 0; attrs[i]; i++)
640                 if (!strcmp(attrs[i]->attr.name, attr->attr.name))
641                         return attrs[i];
642         return NULL;
643 }
644
645 static int attr_add(struct device *dev, struct device_attribute *attr)
646 {
647         struct device_attribute *base_attr;
648
649         /*
650          * Spare the caller from having to copy things it's not interested in.
651          */
652         base_attr = attr_overridden(scsi_sysfs_sdev_attrs, attr);
653         if (base_attr) {
654                 /* extend permissions */
655                 attr->attr.mode |= base_attr->attr.mode;
656
657                 /* override null show/store with default */
658                 if (!attr->show)
659                         attr->show = base_attr->show;
660                 if (!attr->store)
661                         attr->store = base_attr->store;
662         }
663
664         return device_create_file(dev, attr);
665 }
666
667 /**
668  * scsi_sysfs_add_sdev - add scsi device to sysfs
669  * @sdev:       scsi_device to add
670  *
671  * Return value:
672  *      0 on Success / non-zero on Failure
673  **/
674 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
675 {
676         int error, i;
677
678         if ((error = scsi_device_set_state(sdev, SDEV_RUNNING)) != 0)
679                 return error;
680
681         error = device_add(&sdev->sdev_gendev);
682         if (error) {
683                 put_device(sdev->sdev_gendev.parent);
684                 printk(KERN_INFO "error 1\n");
685                 return error;
686         }
687         error = class_device_add(&sdev->sdev_classdev);
688         if (error) {
689                 printk(KERN_INFO "error 2\n");
690                 goto clean_device;
691         }
692
693         /* take a reference for the sdev_classdev; this is
694          * released by the sdev_class .release */
695         get_device(&sdev->sdev_gendev);
696         if (sdev->host->hostt->sdev_attrs) {
697                 for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
698                         error = attr_add(&sdev->sdev_gendev,
699                                         sdev->host->hostt->sdev_attrs[i]);
700                         if (error) {
701                                 __scsi_remove_device(sdev);
702                                 goto out;
703                         }
704                 }
705         }
706         
707         for (i = 0; scsi_sysfs_sdev_attrs[i]; i++) {
708                 if (!attr_overridden(sdev->host->hostt->sdev_attrs,
709                                         scsi_sysfs_sdev_attrs[i])) {
710                         struct device_attribute * attr = 
711                                 attr_changed_internally(sdev->host, 
712                                                         scsi_sysfs_sdev_attrs[i]);
713                         error = device_create_file(&sdev->sdev_gendev, attr);
714                         if (error) {
715                                 __scsi_remove_device(sdev);
716                                 goto out;
717                         }
718                 }
719         }
720
721         transport_add_device(&sdev->sdev_gendev);
722  out:
723         return error;
724
725  clean_device:
726         scsi_device_set_state(sdev, SDEV_CANCEL);
727
728         device_del(&sdev->sdev_gendev);
729         transport_destroy_device(&sdev->sdev_gendev);
730         put_device(&sdev->sdev_gendev);
731
732         return error;
733 }
734
735 void __scsi_remove_device(struct scsi_device *sdev)
736 {
737         struct device *dev = &sdev->sdev_gendev;
738
739         if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
740                 return;
741
742         class_device_unregister(&sdev->sdev_classdev);
743         transport_remove_device(dev);
744         device_del(dev);
745         scsi_device_set_state(sdev, SDEV_DEL);
746         if (sdev->host->hostt->slave_destroy)
747                 sdev->host->hostt->slave_destroy(sdev);
748         transport_destroy_device(dev);
749         put_device(dev);
750 }
751
752 /**
753  * scsi_remove_device - unregister a device from the scsi bus
754  * @sdev:       scsi_device to unregister
755  **/
756 void scsi_remove_device(struct scsi_device *sdev)
757 {
758         struct Scsi_Host *shost = sdev->host;
759
760         mutex_lock(&shost->scan_mutex);
761         __scsi_remove_device(sdev);
762         mutex_unlock(&shost->scan_mutex);
763 }
764 EXPORT_SYMBOL(scsi_remove_device);
765
766 void __scsi_remove_target(struct scsi_target *starget)
767 {
768         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
769         unsigned long flags;
770         struct scsi_device *sdev;
771
772         spin_lock_irqsave(shost->host_lock, flags);
773         starget->reap_ref++;
774  restart:
775         list_for_each_entry(sdev, &shost->__devices, siblings) {
776                 if (sdev->channel != starget->channel ||
777                     sdev->id != starget->id ||
778                     sdev->sdev_state == SDEV_DEL)
779                         continue;
780                 spin_unlock_irqrestore(shost->host_lock, flags);
781                 scsi_remove_device(sdev);
782                 spin_lock_irqsave(shost->host_lock, flags);
783                 goto restart;
784         }
785         spin_unlock_irqrestore(shost->host_lock, flags);
786         scsi_target_reap(starget);
787 }
788
789 static int __remove_child (struct device * dev, void * data)
790 {
791         if (scsi_is_target_device(dev))
792                 __scsi_remove_target(to_scsi_target(dev));
793         return 0;
794 }
795
796 /**
797  * scsi_remove_target - try to remove a target and all its devices
798  * @dev: generic starget or parent of generic stargets to be removed
799  *
800  * Note: This is slightly racy.  It is possible that if the user
801  * requests the addition of another device then the target won't be
802  * removed.
803  */
804 void scsi_remove_target(struct device *dev)
805 {
806         struct device *rdev;
807
808         if (scsi_is_target_device(dev)) {
809                 __scsi_remove_target(to_scsi_target(dev));
810                 return;
811         }
812
813         rdev = get_device(dev);
814         device_for_each_child(dev, NULL, __remove_child);
815         put_device(rdev);
816 }
817 EXPORT_SYMBOL(scsi_remove_target);
818
819 int scsi_register_driver(struct device_driver *drv)
820 {
821         drv->bus = &scsi_bus_type;
822
823         return driver_register(drv);
824 }
825 EXPORT_SYMBOL(scsi_register_driver);
826
827 int scsi_register_interface(struct class_interface *intf)
828 {
829         intf->class = &sdev_class;
830
831         return class_interface_register(intf);
832 }
833 EXPORT_SYMBOL(scsi_register_interface);
834
835
836 static struct class_device_attribute *class_attr_overridden(
837                 struct class_device_attribute **attrs,
838                 struct class_device_attribute *attr)
839 {
840         int i;
841
842         if (!attrs)
843                 return NULL;
844         for (i = 0; attrs[i]; i++)
845                 if (!strcmp(attrs[i]->attr.name, attr->attr.name))
846                         return attrs[i];
847         return NULL;
848 }
849
850 static int class_attr_add(struct class_device *classdev,
851                 struct class_device_attribute *attr)
852 {
853         struct class_device_attribute *base_attr;
854
855         /*
856          * Spare the caller from having to copy things it's not interested in.
857          */
858         base_attr = class_attr_overridden(scsi_sysfs_shost_attrs, attr);
859         if (base_attr) {
860                 /* extend permissions */
861                 attr->attr.mode |= base_attr->attr.mode;
862
863                 /* override null show/store with default */
864                 if (!attr->show)
865                         attr->show = base_attr->show;
866                 if (!attr->store)
867                         attr->store = base_attr->store;
868         }
869
870         return class_device_create_file(classdev, attr);
871 }
872
873 /**
874  * scsi_sysfs_add_host - add scsi host to subsystem
875  * @shost:     scsi host struct to add to subsystem
876  * @dev:       parent struct device pointer
877  **/
878 int scsi_sysfs_add_host(struct Scsi_Host *shost)
879 {
880         int error, i;
881
882         if (shost->hostt->shost_attrs) {
883                 for (i = 0; shost->hostt->shost_attrs[i]; i++) {
884                         error = class_attr_add(&shost->shost_classdev,
885                                         shost->hostt->shost_attrs[i]);
886                         if (error)
887                                 return error;
888                 }
889         }
890
891         for (i = 0; scsi_sysfs_shost_attrs[i]; i++) {
892                 if (!class_attr_overridden(shost->hostt->shost_attrs,
893                                         scsi_sysfs_shost_attrs[i])) {
894                         error = class_device_create_file(&shost->shost_classdev,
895                                         scsi_sysfs_shost_attrs[i]);
896                         if (error)
897                                 return error;
898                 }
899         }
900
901         transport_register_device(&shost->shost_gendev);
902         return 0;
903 }
904
905 void scsi_sysfs_device_initialize(struct scsi_device *sdev)
906 {
907         unsigned long flags;
908         struct Scsi_Host *shost = sdev->host;
909         struct scsi_target  *starget = sdev->sdev_target;
910
911         device_initialize(&sdev->sdev_gendev);
912         sdev->sdev_gendev.bus = &scsi_bus_type;
913         sdev->sdev_gendev.release = scsi_device_dev_release;
914         sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
915                 sdev->host->host_no, sdev->channel, sdev->id,
916                 sdev->lun);
917         
918         class_device_initialize(&sdev->sdev_classdev);
919         sdev->sdev_classdev.dev = &sdev->sdev_gendev;
920         sdev->sdev_classdev.class = &sdev_class;
921         snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
922                  "%d:%d:%d:%d", sdev->host->host_no,
923                  sdev->channel, sdev->id, sdev->lun);
924         sdev->scsi_level = SCSI_2;
925         transport_setup_device(&sdev->sdev_gendev);
926         spin_lock_irqsave(shost->host_lock, flags);
927         list_add_tail(&sdev->same_target_siblings, &starget->devices);
928         list_add_tail(&sdev->siblings, &shost->__devices);
929         spin_unlock_irqrestore(shost->host_lock, flags);
930 }
931
932 int scsi_is_sdev_device(const struct device *dev)
933 {
934         return dev->release == scsi_device_dev_release;
935 }
936 EXPORT_SYMBOL(scsi_is_sdev_device);
937
938 /* A blank transport template that is used in drivers that don't
939  * yet implement Transport Attributes */
940 struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };