1
2
3
4
5#include <linux/module.h>
6#include <linux/fs.h>
7#include <linux/genhd.h>
8#include <linux/kdev_t.h>
9#include <linux/kernel.h>
10#include <linux/blkdev.h>
11#include <linux/init.h>
12#include <linux/spinlock.h>
13#include <linux/proc_fs.h>
14#include <linux/seq_file.h>
15#include <linux/slab.h>
16#include <linux/kmod.h>
17#include <linux/kobj_map.h>
18#include <linux/buffer_head.h>
19#include <linux/mutex.h>
20#include <linux/idr.h>
21
22#include "blk.h"
23
24static DEFINE_MUTEX(block_class_lock);
25#ifndef CONFIG_SYSFS_DEPRECATED
26struct kobject *block_depr;
27#endif
28
29
30#define MAX_EXT_DEVT (1 << MINORBITS)
31
32
33
34
35static DEFINE_MUTEX(ext_devt_mutex);
36static DEFINE_IDR(ext_devt_idr);
37
38static struct device_type disk_type;
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
55{
56 struct hd_struct *part = NULL;
57 struct disk_part_tbl *ptbl;
58
59 if (unlikely(partno < 0))
60 return NULL;
61
62 rcu_read_lock();
63
64 ptbl = rcu_dereference(disk->part_tbl);
65 if (likely(partno < ptbl->len)) {
66 part = rcu_dereference(ptbl->part[partno]);
67 if (part)
68 get_device(part_to_dev(part));
69 }
70
71 rcu_read_unlock();
72
73 return part;
74}
75EXPORT_SYMBOL_GPL(disk_get_part);
76
77
78
79
80
81
82
83
84
85
86
87
88void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
89 unsigned int flags)
90{
91 struct disk_part_tbl *ptbl;
92
93 rcu_read_lock();
94 ptbl = rcu_dereference(disk->part_tbl);
95
96 piter->disk = disk;
97 piter->part = NULL;
98
99 if (flags & DISK_PITER_REVERSE)
100 piter->idx = ptbl->len - 1;
101 else if (flags & DISK_PITER_INCL_PART0)
102 piter->idx = 0;
103 else
104 piter->idx = 1;
105
106 piter->flags = flags;
107
108 rcu_read_unlock();
109}
110EXPORT_SYMBOL_GPL(disk_part_iter_init);
111
112
113
114
115
116
117
118
119
120
121struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
122{
123 struct disk_part_tbl *ptbl;
124 int inc, end;
125
126
127 disk_put_part(piter->part);
128 piter->part = NULL;
129
130
131 rcu_read_lock();
132 ptbl = rcu_dereference(piter->disk->part_tbl);
133
134
135 if (piter->flags & DISK_PITER_REVERSE) {
136 inc = -1;
137 if (piter->flags & DISK_PITER_INCL_PART0)
138 end = -1;
139 else
140 end = 0;
141 } else {
142 inc = 1;
143 end = ptbl->len;
144 }
145
146
147 for (; piter->idx != end; piter->idx += inc) {
148 struct hd_struct *part;
149
150 part = rcu_dereference(ptbl->part[piter->idx]);
151 if (!part)
152 continue;
153 if (!(piter->flags & DISK_PITER_INCL_EMPTY) && !part->nr_sects)
154 continue;
155
156 get_device(part_to_dev(part));
157 piter->part = part;
158 piter->idx += inc;
159 break;
160 }
161
162 rcu_read_unlock();
163
164 return piter->part;
165}
166EXPORT_SYMBOL_GPL(disk_part_iter_next);
167
168
169
170
171
172
173
174
175
176
177void disk_part_iter_exit(struct disk_part_iter *piter)
178{
179 disk_put_part(piter->part);
180 piter->part = NULL;
181}
182EXPORT_SYMBOL_GPL(disk_part_iter_exit);
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
200{
201 struct disk_part_tbl *ptbl;
202 int i;
203
204 ptbl = rcu_dereference(disk->part_tbl);
205
206 for (i = 1; i < ptbl->len; i++) {
207 struct hd_struct *part = rcu_dereference(ptbl->part[i]);
208
209 if (part && part->start_sect <= sector &&
210 sector < part->start_sect + part->nr_sects)
211 return part;
212 }
213 return &disk->part0;
214}
215EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
216
217
218
219
220
221static struct blk_major_name {
222 struct blk_major_name *next;
223 int major;
224 char name[16];
225} *major_names[BLKDEV_MAJOR_HASH_SIZE];
226
227
228static inline int major_to_index(int major)
229{
230 return major % BLKDEV_MAJOR_HASH_SIZE;
231}
232
233#ifdef CONFIG_PROC_FS
234void blkdev_show(struct seq_file *seqf, off_t offset)
235{
236 struct blk_major_name *dp;
237
238 if (offset < BLKDEV_MAJOR_HASH_SIZE) {
239 mutex_lock(&block_class_lock);
240 for (dp = major_names[offset]; dp; dp = dp->next)
241 seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
242 mutex_unlock(&block_class_lock);
243 }
244}
245#endif
246
247int register_blkdev(unsigned int major, const char *name)
248{
249 struct blk_major_name **n, *p;
250 int index, ret = 0;
251
252 mutex_lock(&block_class_lock);
253
254
255 if (major == 0) {
256 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
257 if (major_names[index] == NULL)
258 break;
259 }
260
261 if (index == 0) {
262 printk("register_blkdev: failed to get major for %s\n",
263 name);
264 ret = -EBUSY;
265 goto out;
266 }
267 major = index;
268 ret = major;
269 }
270
271 p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
272 if (p == NULL) {
273 ret = -ENOMEM;
274 goto out;
275 }
276
277 p->major = major;
278 strlcpy(p->name, name, sizeof(p->name));
279 p->next = NULL;
280 index = major_to_index(major);
281
282 for (n = &major_names[index]; *n; n = &(*n)->next) {
283 if ((*n)->major == major)
284 break;
285 }
286 if (!*n)
287 *n = p;
288 else
289 ret = -EBUSY;
290
291 if (ret < 0) {
292 printk("register_blkdev: cannot get major %d for %s\n",
293 major, name);
294 kfree(p);
295 }
296out:
297 mutex_unlock(&block_class_lock);
298 return ret;
299}
300
301EXPORT_SYMBOL(register_blkdev);
302
303void unregister_blkdev(unsigned int major, const char *name)
304{
305 struct blk_major_name **n;
306 struct blk_major_name *p = NULL;
307 int index = major_to_index(major);
308
309 mutex_lock(&block_class_lock);
310 for (n = &major_names[index]; *n; n = &(*n)->next)
311 if ((*n)->major == major)
312 break;
313 if (!*n || strcmp((*n)->name, name)) {
314 WARN_ON(1);
315 } else {
316 p = *n;
317 *n = p->next;
318 }
319 mutex_unlock(&block_class_lock);
320 kfree(p);
321}
322
323EXPORT_SYMBOL(unregister_blkdev);
324
325static struct kobj_map *bdev_map;
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340static int blk_mangle_minor(int minor)
341{
342#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
343 int i;
344
345 for (i = 0; i < MINORBITS / 2; i++) {
346 int low = minor & (1 << i);
347 int high = minor & (1 << (MINORBITS - 1 - i));
348 int distance = MINORBITS - 1 - 2 * i;
349
350 minor ^= low | high;
351 low <<= distance;
352 high >>= distance;
353 minor |= low | high;
354 }
355#endif
356 return minor;
357}
358
359
360
361
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363
364
365
366
367
368
369
370
371
372
373int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
374{
375 struct gendisk *disk = part_to_disk(part);
376 int idx, rc;
377
378
379 if (part->partno < disk->minors) {
380 *devt = MKDEV(disk->major, disk->first_minor + part->partno);
381 return 0;
382 }
383
384
385 do {
386 if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL))
387 return -ENOMEM;
388 rc = idr_get_new(&ext_devt_idr, part, &idx);
389 } while (rc == -EAGAIN);
390
391 if (rc)
392 return rc;
393
394 if (idx > MAX_EXT_DEVT) {
395 idr_remove(&ext_devt_idr, idx);
396 return -EBUSY;
397 }
398
399 *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
400 return 0;
401}
402
403
404
405
406
407
408
409
410
411
412void blk_free_devt(dev_t devt)
413{
414 might_sleep();
415
416 if (devt == MKDEV(0, 0))
417 return;
418
419 if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
420 mutex_lock(&ext_devt_mutex);
421 idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
422 mutex_unlock(&ext_devt_mutex);
423 }
424}
425
426static char *bdevt_str(dev_t devt, char *buf)
427{
428 if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
429 char tbuf[BDEVT_SIZE];
430 snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
431 snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
432 } else
433 snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
434
435 return buf;
436}
437
438
439
440
441
442
443void blk_register_region(dev_t devt, unsigned long range, struct module *module,
444 struct kobject *(*probe)(dev_t, int *, void *),
445 int (*lock)(dev_t, void *), void *data)
446{
447 kobj_map(bdev_map, devt, range, module, probe, lock, data);
448}
449
450EXPORT_SYMBOL(blk_register_region);
451
452void blk_unregister_region(dev_t devt, unsigned long range)
453{
454 kobj_unmap(bdev_map, devt, range);
455}
456
457EXPORT_SYMBOL(blk_unregister_region);
458
459static struct kobject *exact_match(dev_t devt, int *partno, void *data)
460{
461 struct gendisk *p = data;
462
463 return &disk_to_dev(p)->kobj;
464}
465
466static int exact_lock(dev_t devt, void *data)
467{
468 struct gendisk *p = data;
469
470 if (!get_disk(p))
471 return -1;
472 return 0;
473}
474
475
476
477
478
479
480
481
482
483
484void add_disk(struct gendisk *disk)
485{
486 struct backing_dev_info *bdi;
487 dev_t devt;
488 int retval;
489
490
491
492
493
494 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
495 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
496
497 disk->flags |= GENHD_FL_UP;
498
499 retval = blk_alloc_devt(&disk->part0, &devt);
500 if (retval) {
501 WARN_ON(1);
502 return;
503 }
504 disk_to_dev(disk)->devt = devt;
505
506
507
508
509 disk->major = MAJOR(devt);
510 disk->first_minor = MINOR(devt);
511
512 blk_register_region(disk_devt(disk), disk->minors, NULL,
513 exact_match, exact_lock, disk);
514 register_disk(disk);
515 blk_register_queue(disk);
516
517 bdi = &disk->queue->backing_dev_info;
518 bdi_register_dev(bdi, disk_devt(disk));
519 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
520 "bdi");
521 WARN_ON(retval);
522}
523
524EXPORT_SYMBOL(add_disk);
525EXPORT_SYMBOL(del_gendisk);
526
527void unlink_gendisk(struct gendisk *disk)
528{
529 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
530 bdi_unregister(&disk->queue->backing_dev_info);
531 blk_unregister_queue(disk);
532 blk_unregister_region(disk_devt(disk), disk->minors);
533}
534
535
536
537
538
539
540
541
542
543struct gendisk *get_gendisk(dev_t devt, int *partno)
544{
545 struct gendisk *disk = NULL;
546
547 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
548 struct kobject *kobj;
549
550 kobj = kobj_lookup(bdev_map, devt, partno);
551 if (kobj)
552 disk = dev_to_disk(kobj_to_dev(kobj));
553 } else {
554 struct hd_struct *part;
555
556 mutex_lock(&ext_devt_mutex);
557 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
558 if (part && get_disk(part_to_disk(part))) {
559 *partno = part->partno;
560 disk = part_to_disk(part);
561 }
562 mutex_unlock(&ext_devt_mutex);
563 }
564
565 return disk;
566}
567
568
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577
578
579
580
581struct block_device *bdget_disk(struct gendisk *disk, int partno)
582{
583 struct hd_struct *part;
584 struct block_device *bdev = NULL;
585
586 part = disk_get_part(disk, partno);
587 if (part)
588 bdev = bdget(part_devt(part));
589 disk_put_part(part);
590
591 return bdev;
592}
593EXPORT_SYMBOL(bdget_disk);
594
595
596
597
598
599
600void __init printk_all_partitions(void)
601{
602 struct class_dev_iter iter;
603 struct device *dev;
604
605 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
606 while ((dev = class_dev_iter_next(&iter))) {
607 struct gendisk *disk = dev_to_disk(dev);
608 struct disk_part_iter piter;
609 struct hd_struct *part;
610 char name_buf[BDEVNAME_SIZE];
611 char devt_buf[BDEVT_SIZE];
612
613
614
615
616
617 if (get_capacity(disk) == 0 ||
618 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
619 continue;
620
621
622
623
624
625
626 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
627 while ((part = disk_part_iter_next(&piter))) {
628 bool is_part0 = part == &disk->part0;
629
630 printk("%s%s %10llu %s", is_part0 ? "" : " ",
631 bdevt_str(part_devt(part), devt_buf),
632 (unsigned long long)part->nr_sects >> 1,
633 disk_name(disk, part->partno, name_buf));
634 if (is_part0) {
635 if (disk->driverfs_dev != NULL &&
636 disk->driverfs_dev->driver != NULL)
637 printk(" driver: %s\n",
638 disk->driverfs_dev->driver->name);
639 else
640 printk(" (driver?)\n");
641 } else
642 printk("\n");
643 }
644 disk_part_iter_exit(&piter);
645 }
646 class_dev_iter_exit(&iter);
647}
648
649#ifdef CONFIG_PROC_FS
650
651static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
652{
653 loff_t skip = *pos;
654 struct class_dev_iter *iter;
655 struct device *dev;
656
657 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
658 if (!iter)
659 return ERR_PTR(-ENOMEM);
660
661 seqf->private = iter;
662 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
663 do {
664 dev = class_dev_iter_next(iter);
665 if (!dev)
666 return NULL;
667 } while (skip--);
668
669 return dev_to_disk(dev);
670}
671
672static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
673{
674 struct device *dev;
675
676 (*pos)++;
677 dev = class_dev_iter_next(seqf->private);
678 if (dev)
679 return dev_to_disk(dev);
680
681 return NULL;
682}
683
684static void disk_seqf_stop(struct seq_file *seqf, void *v)
685{
686 struct class_dev_iter *iter = seqf->private;
687
688
689 if (iter) {
690 class_dev_iter_exit(iter);
691 kfree(iter);
692 }
693}
694
695static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
696{
697 static void *p;
698
699 p = disk_seqf_start(seqf, pos);
700 if (!IS_ERR(p) && p && !*pos)
701 seq_puts(seqf, "major minor #blocks name\n\n");
702 return p;
703}
704
705static int show_partition(struct seq_file *seqf, void *v)
706{
707 struct gendisk *sgp = v;
708 struct disk_part_iter piter;
709 struct hd_struct *part;
710 char buf[BDEVNAME_SIZE];
711
712
713 if (!get_capacity(sgp) || (!disk_partitionable(sgp) &&
714 (sgp->flags & GENHD_FL_REMOVABLE)))
715 return 0;
716 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
717 return 0;
718
719
720 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
721 while ((part = disk_part_iter_next(&piter)))
722 seq_printf(seqf, "%4d %7d %10llu %s\n",
723 MAJOR(part_devt(part)), MINOR(part_devt(part)),
724 (unsigned long long)part->nr_sects >> 1,
725 disk_name(sgp, part->partno, buf));
726 disk_part_iter_exit(&piter);
727
728 return 0;
729}
730
731static const struct seq_operations partitions_op = {
732 .start = show_partition_start,
733 .next = disk_seqf_next,
734 .stop = disk_seqf_stop,
735 .show = show_partition
736};
737
738static int partitions_open(struct inode *inode, struct file *file)
739{
740 return seq_open(file, &partitions_op);
741}
742
743static const struct file_operations proc_partitions_operations = {
744 .open = partitions_open,
745 .read = seq_read,
746 .llseek = seq_lseek,
747 .release = seq_release,
748};
749#endif
750
751
752static struct kobject *base_probe(dev_t devt, int *partno, void *data)
753{
754 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
755
756 request_module("block-major-%d", MAJOR(devt));
757 return NULL;
758}
759
760static int __init genhd_device_init(void)
761{
762 int error;
763
764 block_class.dev_kobj = sysfs_dev_block_kobj;
765 error = class_register(&block_class);
766 if (unlikely(error))
767 return error;
768 bdev_map = kobj_map_init(base_probe, &block_class_lock);
769 blk_dev_init();
770
771 register_blkdev(BLOCK_EXT_MAJOR, "blkext");
772
773#ifndef CONFIG_SYSFS_DEPRECATED
774
775 block_depr = kobject_create_and_add("block", NULL);
776#endif
777 return 0;
778}
779
780subsys_initcall(genhd_device_init);
781
782static ssize_t disk_range_show(struct device *dev,
783 struct device_attribute *attr, char *buf)
784{
785 struct gendisk *disk = dev_to_disk(dev);
786
787 return sprintf(buf, "%d\n", disk->minors);
788}
789
790static ssize_t disk_ext_range_show(struct device *dev,
791 struct device_attribute *attr, char *buf)
792{
793 struct gendisk *disk = dev_to_disk(dev);
794
795 return sprintf(buf, "%d\n", disk_max_parts(disk));
796}
797
798static ssize_t disk_removable_show(struct device *dev,
799 struct device_attribute *attr, char *buf)
800{
801 struct gendisk *disk = dev_to_disk(dev);
802
803 return sprintf(buf, "%d\n",
804 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
805}
806
807static ssize_t disk_ro_show(struct device *dev,
808 struct device_attribute *attr, char *buf)
809{
810 struct gendisk *disk = dev_to_disk(dev);
811
812 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
813}
814
815static ssize_t disk_capability_show(struct device *dev,
816 struct device_attribute *attr, char *buf)
817{
818 struct gendisk *disk = dev_to_disk(dev);
819
820 return sprintf(buf, "%x\n", disk->flags);
821}
822
823static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
824static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
825static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
826static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
827static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
828static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
829static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
830#ifdef CONFIG_FAIL_MAKE_REQUEST
831static struct device_attribute dev_attr_fail =
832 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
833#endif
834#ifdef CONFIG_FAIL_IO_TIMEOUT
835static struct device_attribute dev_attr_fail_timeout =
836 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
837 part_timeout_store);
838#endif
839
840static struct attribute *disk_attrs[] = {
841 &dev_attr_range.attr,
842 &dev_attr_ext_range.attr,
843 &dev_attr_removable.attr,
844 &dev_attr_ro.attr,
845 &dev_attr_size.attr,
846 &dev_attr_capability.attr,
847 &dev_attr_stat.attr,
848#ifdef CONFIG_FAIL_MAKE_REQUEST
849 &dev_attr_fail.attr,
850#endif
851#ifdef CONFIG_FAIL_IO_TIMEOUT
852 &dev_attr_fail_timeout.attr,
853#endif
854 NULL
855};
856
857static struct attribute_group disk_attr_group = {
858 .attrs = disk_attrs,
859};
860
861static struct attribute_group *disk_attr_groups[] = {
862 &disk_attr_group,
863 NULL
864};
865
866static void disk_free_ptbl_rcu_cb(struct rcu_head *head)
867{
868 struct disk_part_tbl *ptbl =
869 container_of(head, struct disk_part_tbl, rcu_head);
870
871 kfree(ptbl);
872}
873
874
875
876
877
878
879
880
881
882
883
884
885static void disk_replace_part_tbl(struct gendisk *disk,
886 struct disk_part_tbl *new_ptbl)
887{
888 struct disk_part_tbl *old_ptbl = disk->part_tbl;
889
890 rcu_assign_pointer(disk->part_tbl, new_ptbl);
891 if (old_ptbl)
892 call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb);
893}
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909int disk_expand_part_tbl(struct gendisk *disk, int partno)
910{
911 struct disk_part_tbl *old_ptbl = disk->part_tbl;
912 struct disk_part_tbl *new_ptbl;
913 int len = old_ptbl ? old_ptbl->len : 0;
914 int target = partno + 1;
915 size_t size;
916 int i;
917
918
919 if (disk_max_parts(disk) && target > disk_max_parts(disk))
920 return -EINVAL;
921
922 if (target <= len)
923 return 0;
924
925 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
926 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
927 if (!new_ptbl)
928 return -ENOMEM;
929
930 INIT_RCU_HEAD(&new_ptbl->rcu_head);
931 new_ptbl->len = target;
932
933 for (i = 0; i < len; i++)
934 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
935
936 disk_replace_part_tbl(disk, new_ptbl);
937 return 0;
938}
939
940static void disk_release(struct device *dev)
941{
942 struct gendisk *disk = dev_to_disk(dev);
943
944 kfree(disk->random);
945 disk_replace_part_tbl(disk, NULL);
946 free_part_stats(&disk->part0);
947 kfree(disk);
948}
949struct class block_class = {
950 .name = "block",
951};
952
953static struct device_type disk_type = {
954 .name = "disk",
955 .groups = disk_attr_groups,
956 .release = disk_release,
957};
958
959#ifdef CONFIG_PROC_FS
960
961
962
963
964
965
966
967static int diskstats_show(struct seq_file *seqf, void *v)
968{
969 struct gendisk *gp = v;
970 struct disk_part_iter piter;
971 struct hd_struct *hd;
972 char buf[BDEVNAME_SIZE];
973 int cpu;
974
975
976
977
978
979
980
981
982
983 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_PART0);
984 while ((hd = disk_part_iter_next(&piter))) {
985 cpu = part_stat_lock();
986 part_round_stats(cpu, hd);
987 part_stat_unlock();
988 seq_printf(seqf, "%4d %7d %s %lu %lu %llu "
989 "%u %lu %lu %llu %u %u %u %u\n",
990 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
991 disk_name(gp, hd->partno, buf),
992 part_stat_read(hd, ios[0]),
993 part_stat_read(hd, merges[0]),
994 (unsigned long long)part_stat_read(hd, sectors[0]),
995 jiffies_to_msecs(part_stat_read(hd, ticks[0])),
996 part_stat_read(hd, ios[1]),
997 part_stat_read(hd, merges[1]),
998 (unsigned long long)part_stat_read(hd, sectors[1]),
999 jiffies_to_msecs(part_stat_read(hd, ticks[1])),
1000 hd->in_flight,
1001 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1002 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1003 );
1004 }
1005 disk_part_iter_exit(&piter);
1006
1007 return 0;
1008}
1009
1010static const struct seq_operations diskstats_op = {
1011 .start = disk_seqf_start,
1012 .next = disk_seqf_next,
1013 .stop = disk_seqf_stop,
1014 .show = diskstats_show
1015};
1016
1017static int diskstats_open(struct inode *inode, struct file *file)
1018{
1019 return seq_open(file, &diskstats_op);
1020}
1021
1022static const struct file_operations proc_diskstats_operations = {
1023 .open = diskstats_open,
1024 .read = seq_read,
1025 .llseek = seq_lseek,
1026 .release = seq_release,
1027};
1028
1029static int __init proc_genhd_init(void)
1030{
1031 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
1032 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1033 return 0;
1034}
1035module_init(proc_genhd_init);
1036#endif
1037
1038static void media_change_notify_thread(struct work_struct *work)
1039{
1040 struct gendisk *gd = container_of(work, struct gendisk, async_notify);
1041 char event[] = "MEDIA_CHANGE=1";
1042 char *envp[] = { event, NULL };
1043
1044
1045
1046
1047
1048 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
1049 put_device(gd->driverfs_dev);
1050}
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061dev_t blk_lookup_devt(const char *name, int partno)
1062{
1063 dev_t devt = MKDEV(0, 0);
1064 struct class_dev_iter iter;
1065 struct device *dev;
1066
1067 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1068 while ((dev = class_dev_iter_next(&iter))) {
1069 struct gendisk *disk = dev_to_disk(dev);
1070 struct hd_struct *part;
1071
1072 if (strcmp(dev->bus_id, name))
1073 continue;
1074
1075 part = disk_get_part(disk, partno);
1076 if (part) {
1077 devt = part_devt(part);
1078 disk_put_part(part);
1079 break;
1080 }
1081 disk_put_part(part);
1082 }
1083 class_dev_iter_exit(&iter);
1084 return devt;
1085}
1086EXPORT_SYMBOL(blk_lookup_devt);
1087
1088struct gendisk *alloc_disk(int minors)
1089{
1090 return alloc_disk_node(minors, -1);
1091}
1092EXPORT_SYMBOL(alloc_disk);
1093
1094struct gendisk *alloc_disk_node(int minors, int node_id)
1095{
1096 struct gendisk *disk;
1097
1098 disk = kmalloc_node(sizeof(struct gendisk),
1099 GFP_KERNEL | __GFP_ZERO, node_id);
1100 if (disk) {
1101 if (!init_part_stats(&disk->part0)) {
1102 kfree(disk);
1103 return NULL;
1104 }
1105 disk->node_id = node_id;
1106 if (disk_expand_part_tbl(disk, 0)) {
1107 free_part_stats(&disk->part0);
1108 kfree(disk);
1109 return NULL;
1110 }
1111 disk->part_tbl->part[0] = &disk->part0;
1112
1113 disk->minors = minors;
1114 rand_initialize_disk(disk);
1115 disk_to_dev(disk)->class = &block_class;
1116 disk_to_dev(disk)->type = &disk_type;
1117 device_initialize(disk_to_dev(disk));
1118 INIT_WORK(&disk->async_notify,
1119 media_change_notify_thread);
1120 }
1121 return disk;
1122}
1123EXPORT_SYMBOL(alloc_disk_node);
1124
1125struct kobject *get_disk(struct gendisk *disk)
1126{
1127 struct module *owner;
1128 struct kobject *kobj;
1129
1130 if (!disk->fops)
1131 return NULL;
1132 owner = disk->fops->owner;
1133 if (owner && !try_module_get(owner))
1134 return NULL;
1135 kobj = kobject_get(&disk_to_dev(disk)->kobj);
1136 if (kobj == NULL) {
1137 module_put(owner);
1138 return NULL;
1139 }
1140 return kobj;
1141
1142}
1143
1144EXPORT_SYMBOL(get_disk);
1145
1146void put_disk(struct gendisk *disk)
1147{
1148 if (disk)
1149 kobject_put(&disk_to_dev(disk)->kobj);
1150}
1151
1152EXPORT_SYMBOL(put_disk);
1153
1154void set_device_ro(struct block_device *bdev, int flag)
1155{
1156 bdev->bd_part->policy = flag;
1157}
1158
1159EXPORT_SYMBOL(set_device_ro);
1160
1161void set_disk_ro(struct gendisk *disk, int flag)
1162{
1163 struct disk_part_iter piter;
1164 struct hd_struct *part;
1165
1166 disk_part_iter_init(&piter, disk,
1167 DISK_PITER_INCL_EMPTY | DISK_PITER_INCL_PART0);
1168 while ((part = disk_part_iter_next(&piter)))
1169 part->policy = flag;
1170 disk_part_iter_exit(&piter);
1171}
1172
1173EXPORT_SYMBOL(set_disk_ro);
1174
1175int bdev_read_only(struct block_device *bdev)
1176{
1177 if (!bdev)
1178 return 0;
1179 return bdev->bd_part->policy;
1180}
1181
1182EXPORT_SYMBOL(bdev_read_only);
1183
1184int invalidate_partition(struct gendisk *disk, int partno)
1185{
1186 int res = 0;
1187 struct block_device *bdev = bdget_disk(disk, partno);
1188 if (bdev) {
1189 fsync_bdev(bdev);
1190 res = __invalidate_device(bdev);
1191 bdput(bdev);
1192 }
1193 return res;
1194}
1195
1196EXPORT_SYMBOL(invalidate_partition);