5 #include <linux/module.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/seq_file.h>
14 #include <linux/slab.h>
15 #include <linux/kmod.h>
16 #include <linux/kobj_map.h>
17 #include <linux/buffer_head.h>
18 #include <linux/mutex.h>
22 static DEFINE_MUTEX(block_class_lock);
23 #ifndef CONFIG_SYSFS_DEPRECATED
24 struct kobject *block_depr;
27 static struct device_type disk_type;
30 * Can be deleted altogether. Later.
33 static struct blk_major_name {
34 struct blk_major_name *next;
37 } *major_names[BLKDEV_MAJOR_HASH_SIZE];
39 /* index in the above - for now: assume no multimajor ranges */
40 static inline int major_to_index(int major)
42 return major % BLKDEV_MAJOR_HASH_SIZE;
46 void blkdev_show(struct seq_file *seqf, off_t offset)
48 struct blk_major_name *dp;
50 if (offset < BLKDEV_MAJOR_HASH_SIZE) {
51 mutex_lock(&block_class_lock);
52 for (dp = major_names[offset]; dp; dp = dp->next)
53 seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
54 mutex_unlock(&block_class_lock);
57 #endif /* CONFIG_PROC_FS */
59 int register_blkdev(unsigned int major, const char *name)
61 struct blk_major_name **n, *p;
64 mutex_lock(&block_class_lock);
68 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
69 if (major_names[index] == NULL)
74 printk("register_blkdev: failed to get major for %s\n",
83 p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
90 strlcpy(p->name, name, sizeof(p->name));
92 index = major_to_index(major);
94 for (n = &major_names[index]; *n; n = &(*n)->next) {
95 if ((*n)->major == major)
104 printk("register_blkdev: cannot get major %d for %s\n",
109 mutex_unlock(&block_class_lock);
113 EXPORT_SYMBOL(register_blkdev);
115 void unregister_blkdev(unsigned int major, const char *name)
117 struct blk_major_name **n;
118 struct blk_major_name *p = NULL;
119 int index = major_to_index(major);
121 mutex_lock(&block_class_lock);
122 for (n = &major_names[index]; *n; n = &(*n)->next)
123 if ((*n)->major == major)
125 if (!*n || strcmp((*n)->name, name)) {
131 mutex_unlock(&block_class_lock);
135 EXPORT_SYMBOL(unregister_blkdev);
137 static struct kobj_map *bdev_map;
140 * Register device numbers dev..(dev+range-1)
141 * range must be nonzero
142 * The hash chain is sorted on range, so that subranges can override.
144 void blk_register_region(dev_t devt, unsigned long range, struct module *module,
145 struct kobject *(*probe)(dev_t, int *, void *),
146 int (*lock)(dev_t, void *), void *data)
148 kobj_map(bdev_map, devt, range, module, probe, lock, data);
151 EXPORT_SYMBOL(blk_register_region);
153 void blk_unregister_region(dev_t devt, unsigned long range)
155 kobj_unmap(bdev_map, devt, range);
158 EXPORT_SYMBOL(blk_unregister_region);
160 static struct kobject *exact_match(dev_t devt, int *partno, void *data)
162 struct gendisk *p = data;
167 static int exact_lock(dev_t devt, void *data)
169 struct gendisk *p = data;
177 * add_disk - add partitioning information to kernel list
178 * @disk: per-device partitioning information
180 * This function registers the partitioning information in @disk
183 void add_disk(struct gendisk *disk)
185 struct backing_dev_info *bdi;
188 disk->flags |= GENHD_FL_UP;
189 disk->dev.devt = MKDEV(disk->major, disk->first_minor);
190 blk_register_region(disk_devt(disk), disk->minors, NULL,
191 exact_match, exact_lock, disk);
193 blk_register_queue(disk);
195 bdi = &disk->queue->backing_dev_info;
196 bdi_register_dev(bdi, disk_devt(disk));
197 retval = sysfs_create_link(&disk->dev.kobj, &bdi->dev->kobj, "bdi");
201 EXPORT_SYMBOL(add_disk);
202 EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */
204 void unlink_gendisk(struct gendisk *disk)
206 sysfs_remove_link(&disk->dev.kobj, "bdi");
207 bdi_unregister(&disk->queue->backing_dev_info);
208 blk_unregister_queue(disk);
209 blk_unregister_region(disk_devt(disk), disk->minors);
213 * get_gendisk - get partitioning information for a given device
214 * @devt: device to get partitioning information for
215 * @part: returned partition index
217 * This function gets the structure containing partitioning
218 * information for the given device @devt.
220 struct gendisk *get_gendisk(dev_t devt, int *partno)
222 struct kobject *kobj = kobj_lookup(bdev_map, devt, partno);
223 struct device *dev = kobj_to_dev(kobj);
225 return kobj ? dev_to_disk(dev) : NULL;
229 * bdget_disk - do bdget() by gendisk and partition number
230 * @disk: gendisk of interest
231 * @partno: partition number
233 * Find partition @partno from @disk, do bdget() on it.
239 * Resulting block_device on success, NULL on failure.
241 extern struct block_device *bdget_disk(struct gendisk *disk, int partno)
243 dev_t devt = MKDEV(0, 0);
246 devt = disk_devt(disk);
248 struct hd_struct *part = disk->part[partno - 1];
250 if (part && part->nr_sects)
251 devt = part_devt(part);
254 if (likely(devt != MKDEV(0, 0)))
258 EXPORT_SYMBOL(bdget_disk);
261 * print a full list of all partitions - intended for places where the root
262 * filesystem can't be mounted and thus to give the victim some idea of what
265 void __init printk_all_partitions(void)
267 struct class_dev_iter iter;
270 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
271 while ((dev = class_dev_iter_next(&iter))) {
272 struct gendisk *disk = dev_to_disk(dev);
273 char buf[BDEVNAME_SIZE];
277 * Don't show empty devices or things that have been
280 if (get_capacity(disk) == 0 ||
281 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
285 * Note, unlike /proc/partitions, I am showing the
286 * numbers in hex - the same format as the root=
289 printk("%02x%02x %10llu %s",
290 MAJOR(disk_devt(disk)), MINOR(disk_devt(disk)),
291 (unsigned long long)get_capacity(disk) >> 1,
292 disk_name(disk, 0, buf));
293 if (disk->driverfs_dev != NULL &&
294 disk->driverfs_dev->driver != NULL)
295 printk(" driver: %s\n",
296 disk->driverfs_dev->driver->name);
298 printk(" (driver?)\n");
300 /* now show the partitions */
301 for (n = 0; n < disk_max_parts(disk); ++n) {
302 struct hd_struct *part = disk->part[n];
304 if (!part || !part->nr_sects)
306 printk(" %02x%02x %10llu %s\n",
307 MAJOR(part_devt(part)), MINOR(part_devt(part)),
308 (unsigned long long)part->nr_sects >> 1,
309 disk_name(disk, part->partno, buf));
312 class_dev_iter_exit(&iter);
315 #ifdef CONFIG_PROC_FS
317 static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
320 struct class_dev_iter *iter;
323 iter = kmalloc(GFP_KERNEL, sizeof(*iter));
325 return ERR_PTR(-ENOMEM);
327 seqf->private = iter;
328 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
330 dev = class_dev_iter_next(iter);
335 return dev_to_disk(dev);
338 static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
343 dev = class_dev_iter_next(seqf->private);
345 return dev_to_disk(dev);
350 static void disk_seqf_stop(struct seq_file *seqf, void *v)
352 struct class_dev_iter *iter = seqf->private;
354 /* stop is called even after start failed :-( */
356 class_dev_iter_exit(iter);
361 static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
365 p = disk_seqf_start(seqf, pos);
367 seq_puts(seqf, "major minor #blocks name\n\n");
371 static int show_partition(struct seq_file *seqf, void *v)
373 struct gendisk *sgp = v;
375 char buf[BDEVNAME_SIZE];
377 /* Don't show non-partitionable removeable devices or empty devices */
378 if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
379 (sgp->flags & GENHD_FL_REMOVABLE)))
381 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
384 /* show the full disk and all non-0 size partitions of it */
385 seq_printf(seqf, "%4d %4d %10llu %s\n",
386 MAJOR(disk_devt(sgp)), MINOR(disk_devt(sgp)),
387 (unsigned long long)get_capacity(sgp) >> 1,
388 disk_name(sgp, 0, buf));
389 for (n = 0; n < disk_max_parts(sgp); n++) {
390 struct hd_struct *part = sgp->part[n];
393 if (part->nr_sects == 0)
395 seq_printf(seqf, "%4d %4d %10llu %s\n",
396 MAJOR(part_devt(part)), MINOR(part_devt(part)),
397 (unsigned long long)part->nr_sects >> 1,
398 disk_name(sgp, part->partno, buf));
404 const struct seq_operations partitions_op = {
405 .start = show_partition_start,
406 .next = disk_seqf_next,
407 .stop = disk_seqf_stop,
408 .show = show_partition
413 static struct kobject *base_probe(dev_t devt, int *partno, void *data)
415 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
416 /* Make old-style 2.4 aliases work */
417 request_module("block-major-%d", MAJOR(devt));
421 static int __init genhd_device_init(void)
425 block_class.dev_kobj = sysfs_dev_block_kobj;
426 error = class_register(&block_class);
429 bdev_map = kobj_map_init(base_probe, &block_class_lock);
432 #ifndef CONFIG_SYSFS_DEPRECATED
433 /* create top-level block dir */
434 block_depr = kobject_create_and_add("block", NULL);
439 subsys_initcall(genhd_device_init);
441 static ssize_t disk_range_show(struct device *dev,
442 struct device_attribute *attr, char *buf)
444 struct gendisk *disk = dev_to_disk(dev);
446 return sprintf(buf, "%d\n", disk->minors);
449 static ssize_t disk_removable_show(struct device *dev,
450 struct device_attribute *attr, char *buf)
452 struct gendisk *disk = dev_to_disk(dev);
454 return sprintf(buf, "%d\n",
455 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
458 static ssize_t disk_ro_show(struct device *dev,
459 struct device_attribute *attr, char *buf)
461 struct gendisk *disk = dev_to_disk(dev);
463 return sprintf(buf, "%d\n", disk->policy ? 1 : 0);
466 static ssize_t disk_size_show(struct device *dev,
467 struct device_attribute *attr, char *buf)
469 struct gendisk *disk = dev_to_disk(dev);
471 return sprintf(buf, "%llu\n", (unsigned long long)get_capacity(disk));
474 static ssize_t disk_capability_show(struct device *dev,
475 struct device_attribute *attr, char *buf)
477 struct gendisk *disk = dev_to_disk(dev);
479 return sprintf(buf, "%x\n", disk->flags);
482 static ssize_t disk_stat_show(struct device *dev,
483 struct device_attribute *attr, char *buf)
485 struct gendisk *disk = dev_to_disk(dev);
488 disk_round_stats(disk);
491 "%8lu %8lu %8llu %8u "
492 "%8lu %8lu %8llu %8u "
495 disk_stat_read(disk, ios[READ]),
496 disk_stat_read(disk, merges[READ]),
497 (unsigned long long)disk_stat_read(disk, sectors[READ]),
498 jiffies_to_msecs(disk_stat_read(disk, ticks[READ])),
499 disk_stat_read(disk, ios[WRITE]),
500 disk_stat_read(disk, merges[WRITE]),
501 (unsigned long long)disk_stat_read(disk, sectors[WRITE]),
502 jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])),
504 jiffies_to_msecs(disk_stat_read(disk, io_ticks)),
505 jiffies_to_msecs(disk_stat_read(disk, time_in_queue)));
508 #ifdef CONFIG_FAIL_MAKE_REQUEST
509 static ssize_t disk_fail_show(struct device *dev,
510 struct device_attribute *attr, char *buf)
512 struct gendisk *disk = dev_to_disk(dev);
514 return sprintf(buf, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
517 static ssize_t disk_fail_store(struct device *dev,
518 struct device_attribute *attr,
519 const char *buf, size_t count)
521 struct gendisk *disk = dev_to_disk(dev);
524 if (count > 0 && sscanf(buf, "%d", &i) > 0) {
526 disk->flags &= ~GENHD_FL_FAIL;
528 disk->flags |= GENHD_FL_FAIL;
536 static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
537 static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
538 static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
539 static DEVICE_ATTR(size, S_IRUGO, disk_size_show, NULL);
540 static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
541 static DEVICE_ATTR(stat, S_IRUGO, disk_stat_show, NULL);
542 #ifdef CONFIG_FAIL_MAKE_REQUEST
543 static struct device_attribute dev_attr_fail =
544 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, disk_fail_show, disk_fail_store);
547 static struct attribute *disk_attrs[] = {
548 &dev_attr_range.attr,
549 &dev_attr_removable.attr,
552 &dev_attr_capability.attr,
554 #ifdef CONFIG_FAIL_MAKE_REQUEST
560 static struct attribute_group disk_attr_group = {
564 static struct attribute_group *disk_attr_groups[] = {
569 static void disk_release(struct device *dev)
571 struct gendisk *disk = dev_to_disk(dev);
575 free_disk_stats(disk);
578 struct class block_class = {
582 static struct device_type disk_type = {
584 .groups = disk_attr_groups,
585 .release = disk_release,
588 #ifdef CONFIG_PROC_FS
590 * aggregate disk stat collector. Uses the same stats that the sysfs
591 * entries do, above, but makes them available through one seq_file.
593 * The output looks suspiciously like /proc/partitions with a bunch of
596 static int diskstats_show(struct seq_file *seqf, void *v)
598 struct gendisk *gp = v;
599 char buf[BDEVNAME_SIZE];
603 if (&gp->dev.kobj.entry == block_class.devices.next)
604 seq_puts(seqf, "major minor name"
605 " rio rmerge rsect ruse wio wmerge "
606 "wsect wuse running use aveq"
611 disk_round_stats(gp);
613 seq_printf(seqf, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
614 MAJOR(disk_devt(gp)), MINOR(disk_devt(gp)),
615 disk_name(gp, 0, buf),
616 disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
617 (unsigned long long)disk_stat_read(gp, sectors[0]),
618 jiffies_to_msecs(disk_stat_read(gp, ticks[0])),
619 disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]),
620 (unsigned long long)disk_stat_read(gp, sectors[1]),
621 jiffies_to_msecs(disk_stat_read(gp, ticks[1])),
623 jiffies_to_msecs(disk_stat_read(gp, io_ticks)),
624 jiffies_to_msecs(disk_stat_read(gp, time_in_queue)));
626 /* now show all non-0 size partitions of it */
627 for (n = 0; n < disk_max_parts(gp); n++) {
628 struct hd_struct *hd = gp->part[n];
630 if (!hd || !hd->nr_sects)
634 part_round_stats(hd);
636 seq_printf(seqf, "%4d %4d %s %lu %lu %llu "
637 "%u %lu %lu %llu %u %u %u %u\n",
638 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
639 disk_name(gp, hd->partno, buf),
640 part_stat_read(hd, ios[0]),
641 part_stat_read(hd, merges[0]),
642 (unsigned long long)part_stat_read(hd, sectors[0]),
643 jiffies_to_msecs(part_stat_read(hd, ticks[0])),
644 part_stat_read(hd, ios[1]),
645 part_stat_read(hd, merges[1]),
646 (unsigned long long)part_stat_read(hd, sectors[1]),
647 jiffies_to_msecs(part_stat_read(hd, ticks[1])),
649 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
650 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
657 const struct seq_operations diskstats_op = {
658 .start = disk_seqf_start,
659 .next = disk_seqf_next,
660 .stop = disk_seqf_stop,
661 .show = diskstats_show
663 #endif /* CONFIG_PROC_FS */
665 static void media_change_notify_thread(struct work_struct *work)
667 struct gendisk *gd = container_of(work, struct gendisk, async_notify);
668 char event[] = "MEDIA_CHANGE=1";
669 char *envp[] = { event, NULL };
672 * set enviroment vars to indicate which event this is for
673 * so that user space will know to go check the media status.
675 kobject_uevent_env(&gd->dev.kobj, KOBJ_CHANGE, envp);
676 put_device(gd->driverfs_dev);
680 void genhd_media_change_notify(struct gendisk *disk)
682 get_device(disk->driverfs_dev);
683 schedule_work(&disk->async_notify);
685 EXPORT_SYMBOL_GPL(genhd_media_change_notify);
688 dev_t blk_lookup_devt(const char *name, int partno)
690 dev_t devt = MKDEV(0, 0);
691 struct class_dev_iter iter;
694 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
695 while ((dev = class_dev_iter_next(&iter))) {
696 struct gendisk *disk = dev_to_disk(dev);
698 if (strcmp(dev->bus_id, name))
700 if (partno < 0 || partno > disk_max_parts(disk))
704 devt = disk_devt(disk);
706 struct hd_struct *part = disk->part[partno - 1];
708 if (!part || !part->nr_sects)
711 devt = part_devt(part);
715 class_dev_iter_exit(&iter);
718 EXPORT_SYMBOL(blk_lookup_devt);
720 struct gendisk *alloc_disk(int minors)
722 return alloc_disk_node(minors, -1);
725 struct gendisk *alloc_disk_node(int minors, int node_id)
727 struct gendisk *disk;
729 disk = kmalloc_node(sizeof(struct gendisk),
730 GFP_KERNEL | __GFP_ZERO, node_id);
732 if (!init_disk_stats(disk)) {
737 int size = (minors - 1) * sizeof(struct hd_struct *);
738 disk->part = kmalloc_node(size,
739 GFP_KERNEL | __GFP_ZERO, node_id);
741 free_disk_stats(disk);
746 disk->minors = minors;
747 rand_initialize_disk(disk);
748 disk->dev.class = &block_class;
749 disk->dev.type = &disk_type;
750 device_initialize(&disk->dev);
751 INIT_WORK(&disk->async_notify,
752 media_change_notify_thread);
757 EXPORT_SYMBOL(alloc_disk);
758 EXPORT_SYMBOL(alloc_disk_node);
760 struct kobject *get_disk(struct gendisk *disk)
762 struct module *owner;
763 struct kobject *kobj;
767 owner = disk->fops->owner;
768 if (owner && !try_module_get(owner))
770 kobj = kobject_get(&disk->dev.kobj);
779 EXPORT_SYMBOL(get_disk);
781 void put_disk(struct gendisk *disk)
784 kobject_put(&disk->dev.kobj);
787 EXPORT_SYMBOL(put_disk);
789 void set_device_ro(struct block_device *bdev, int flag)
791 if (bdev->bd_contains != bdev)
792 bdev->bd_part->policy = flag;
794 bdev->bd_disk->policy = flag;
797 EXPORT_SYMBOL(set_device_ro);
799 void set_disk_ro(struct gendisk *disk, int flag)
803 for (i = 0; i < disk_max_parts(disk); i++)
804 if (disk->part[i]) disk->part[i]->policy = flag;
807 EXPORT_SYMBOL(set_disk_ro);
809 int bdev_read_only(struct block_device *bdev)
813 else if (bdev->bd_contains != bdev)
814 return bdev->bd_part->policy;
816 return bdev->bd_disk->policy;
819 EXPORT_SYMBOL(bdev_read_only);
821 int invalidate_partition(struct gendisk *disk, int partno)
824 struct block_device *bdev = bdget_disk(disk, partno);
827 res = __invalidate_device(bdev);
833 EXPORT_SYMBOL(invalidate_partition);