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 *f, 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(f, "%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 *part, 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 blk_register_region(MKDEV(disk->major, disk->first_minor),
190 disk->minors, NULL, exact_match, exact_lock, disk);
192 blk_register_queue(disk);
194 bdi = &disk->queue->backing_dev_info;
195 bdi_register_dev(bdi, MKDEV(disk->major, disk->first_minor));
196 retval = sysfs_create_link(&disk->dev.kobj, &bdi->dev->kobj, "bdi");
200 EXPORT_SYMBOL(add_disk);
201 EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */
203 void unlink_gendisk(struct gendisk *disk)
205 sysfs_remove_link(&disk->dev.kobj, "bdi");
206 bdi_unregister(&disk->queue->backing_dev_info);
207 blk_unregister_queue(disk);
208 blk_unregister_region(MKDEV(disk->major, disk->first_minor),
213 * get_gendisk - get partitioning information for a given device
214 * @dev: device to get partitioning information for
216 * This function gets the structure containing partitioning
217 * information for the given device @dev.
219 struct gendisk *get_gendisk(dev_t devt, int *part)
221 struct kobject *kobj = kobj_lookup(bdev_map, devt, part);
222 struct device *dev = kobj_to_dev(kobj);
224 return kobj ? dev_to_disk(dev) : NULL;
228 * print a partitions - intended for places where the root filesystem can't be
229 * mounted and thus to give the victim some idea of what went wrong
231 static int printk_partition(struct device *dev, void *data)
234 char buf[BDEVNAME_SIZE];
237 if (dev->type != &disk_type)
240 sgp = dev_to_disk(dev);
242 * Don't show empty devices or things that have been surpressed
244 if (get_capacity(sgp) == 0 ||
245 (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
249 * Note, unlike /proc/partitions, I am showing the numbers in
250 * hex - the same format as the root= option takes.
252 printk("%02x%02x %10llu %s",
253 sgp->major, sgp->first_minor,
254 (unsigned long long)get_capacity(sgp) >> 1,
255 disk_name(sgp, 0, buf));
256 if (sgp->driverfs_dev != NULL &&
257 sgp->driverfs_dev->driver != NULL)
258 printk(" driver: %s\n",
259 sgp->driverfs_dev->driver->name);
261 printk(" (driver?)\n");
263 /* now show the partitions */
264 for (n = 0; n < sgp->minors - 1; ++n) {
265 if (sgp->part[n] == NULL)
267 if (sgp->part[n]->nr_sects == 0)
269 printk(" %02x%02x %10llu %s\n",
270 sgp->major, n + 1 + sgp->first_minor,
271 (unsigned long long)sgp->part[n]->nr_sects >> 1,
272 disk_name(sgp, n + 1, buf));
279 * print a full list of all partitions - intended for places where the root
280 * filesystem can't be mounted and thus to give the victim some idea of what
283 void __init printk_all_partitions(void)
285 mutex_lock(&block_class_lock);
286 class_for_each_device(&block_class, NULL, NULL, printk_partition);
287 mutex_unlock(&block_class_lock);
290 #ifdef CONFIG_PROC_FS
292 static int find_start(struct device *dev, void *data)
296 if (dev->type != &disk_type)
304 static void *part_start(struct seq_file *part, loff_t *pos)
310 seq_puts(part, "major minor #blocks name\n\n");
312 mutex_lock(&block_class_lock);
313 dev = class_find_device(&block_class, NULL, &k, find_start);
316 return dev_to_disk(dev);
321 static int find_next(struct device *dev, void *data)
323 if (dev->type == &disk_type)
328 static void *part_next(struct seq_file *part, void *v, loff_t *pos)
330 struct gendisk *gp = v;
333 dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
336 return dev_to_disk(dev);
341 static void part_stop(struct seq_file *part, void *v)
343 mutex_unlock(&block_class_lock);
346 static int show_partition(struct seq_file *part, void *v)
348 struct gendisk *sgp = v;
350 char buf[BDEVNAME_SIZE];
352 /* Don't show non-partitionable removeable devices or empty devices */
353 if (!get_capacity(sgp) ||
354 (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
356 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
359 /* show the full disk and all non-0 size partitions of it */
360 seq_printf(part, "%4d %4d %10llu %s\n",
361 sgp->major, sgp->first_minor,
362 (unsigned long long)get_capacity(sgp) >> 1,
363 disk_name(sgp, 0, buf));
364 for (n = 0; n < sgp->minors - 1; n++) {
367 if (sgp->part[n]->nr_sects == 0)
369 seq_printf(part, "%4d %4d %10llu %s\n",
370 sgp->major, n + 1 + sgp->first_minor,
371 (unsigned long long)sgp->part[n]->nr_sects >> 1 ,
372 disk_name(sgp, n + 1, buf));
378 const struct seq_operations partitions_op = {
382 .show = show_partition
387 static struct kobject *base_probe(dev_t devt, int *part, void *data)
389 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
390 /* Make old-style 2.4 aliases work */
391 request_module("block-major-%d", MAJOR(devt));
395 static int __init genhd_device_init(void)
399 block_class.dev_kobj = sysfs_dev_block_kobj;
400 error = class_register(&block_class);
403 bdev_map = kobj_map_init(base_probe, &block_class_lock);
406 #ifndef CONFIG_SYSFS_DEPRECATED
407 /* create top-level block dir */
408 block_depr = kobject_create_and_add("block", NULL);
413 subsys_initcall(genhd_device_init);
415 static ssize_t disk_range_show(struct device *dev,
416 struct device_attribute *attr, char *buf)
418 struct gendisk *disk = dev_to_disk(dev);
420 return sprintf(buf, "%d\n", disk->minors);
423 static ssize_t disk_removable_show(struct device *dev,
424 struct device_attribute *attr, char *buf)
426 struct gendisk *disk = dev_to_disk(dev);
428 return sprintf(buf, "%d\n",
429 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
432 static ssize_t disk_ro_show(struct device *dev,
433 struct device_attribute *attr, char *buf)
435 struct gendisk *disk = dev_to_disk(dev);
437 return sprintf(buf, "%d\n", disk->policy ? 1 : 0);
440 static ssize_t disk_size_show(struct device *dev,
441 struct device_attribute *attr, char *buf)
443 struct gendisk *disk = dev_to_disk(dev);
445 return sprintf(buf, "%llu\n", (unsigned long long)get_capacity(disk));
448 static ssize_t disk_capability_show(struct device *dev,
449 struct device_attribute *attr, char *buf)
451 struct gendisk *disk = dev_to_disk(dev);
453 return sprintf(buf, "%x\n", disk->flags);
456 static ssize_t disk_stat_show(struct device *dev,
457 struct device_attribute *attr, char *buf)
459 struct gendisk *disk = dev_to_disk(dev);
462 disk_round_stats(disk);
465 "%8lu %8lu %8llu %8u "
466 "%8lu %8lu %8llu %8u "
469 disk_stat_read(disk, ios[READ]),
470 disk_stat_read(disk, merges[READ]),
471 (unsigned long long)disk_stat_read(disk, sectors[READ]),
472 jiffies_to_msecs(disk_stat_read(disk, ticks[READ])),
473 disk_stat_read(disk, ios[WRITE]),
474 disk_stat_read(disk, merges[WRITE]),
475 (unsigned long long)disk_stat_read(disk, sectors[WRITE]),
476 jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])),
478 jiffies_to_msecs(disk_stat_read(disk, io_ticks)),
479 jiffies_to_msecs(disk_stat_read(disk, time_in_queue)));
482 #ifdef CONFIG_FAIL_MAKE_REQUEST
483 static ssize_t disk_fail_show(struct device *dev,
484 struct device_attribute *attr, char *buf)
486 struct gendisk *disk = dev_to_disk(dev);
488 return sprintf(buf, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
491 static ssize_t disk_fail_store(struct device *dev,
492 struct device_attribute *attr,
493 const char *buf, size_t count)
495 struct gendisk *disk = dev_to_disk(dev);
498 if (count > 0 && sscanf(buf, "%d", &i) > 0) {
500 disk->flags &= ~GENHD_FL_FAIL;
502 disk->flags |= GENHD_FL_FAIL;
510 static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
511 static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
512 static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
513 static DEVICE_ATTR(size, S_IRUGO, disk_size_show, NULL);
514 static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
515 static DEVICE_ATTR(stat, S_IRUGO, disk_stat_show, NULL);
516 #ifdef CONFIG_FAIL_MAKE_REQUEST
517 static struct device_attribute dev_attr_fail =
518 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, disk_fail_show, disk_fail_store);
521 static struct attribute *disk_attrs[] = {
522 &dev_attr_range.attr,
523 &dev_attr_removable.attr,
526 &dev_attr_capability.attr,
528 #ifdef CONFIG_FAIL_MAKE_REQUEST
534 static struct attribute_group disk_attr_group = {
538 static struct attribute_group *disk_attr_groups[] = {
543 static void disk_release(struct device *dev)
545 struct gendisk *disk = dev_to_disk(dev);
549 free_disk_stats(disk);
552 struct class block_class = {
556 static struct device_type disk_type = {
558 .groups = disk_attr_groups,
559 .release = disk_release,
562 #ifdef CONFIG_PROC_FS
564 * aggregate disk stat collector. Uses the same stats that the sysfs
565 * entries do, above, but makes them available through one seq_file.
567 * The output looks suspiciously like /proc/partitions with a bunch of
571 static void *diskstats_start(struct seq_file *part, loff_t *pos)
576 mutex_lock(&block_class_lock);
577 dev = class_find_device(&block_class, NULL, &k, find_start);
580 return dev_to_disk(dev);
585 static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
587 struct gendisk *gp = v;
591 dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
594 return dev_to_disk(dev);
599 static void diskstats_stop(struct seq_file *part, void *v)
601 mutex_unlock(&block_class_lock);
604 static int diskstats_show(struct seq_file *s, void *v)
606 struct gendisk *gp = v;
607 char buf[BDEVNAME_SIZE];
611 if (&gp->dev.kobj.entry == block_class.devices.next)
612 seq_puts(s, "major minor name"
613 " rio rmerge rsect ruse wio wmerge "
614 "wsect wuse running use aveq"
619 disk_round_stats(gp);
621 seq_printf(s, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
622 gp->major, n + gp->first_minor, disk_name(gp, n, buf),
623 disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
624 (unsigned long long)disk_stat_read(gp, sectors[0]),
625 jiffies_to_msecs(disk_stat_read(gp, ticks[0])),
626 disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]),
627 (unsigned long long)disk_stat_read(gp, sectors[1]),
628 jiffies_to_msecs(disk_stat_read(gp, ticks[1])),
630 jiffies_to_msecs(disk_stat_read(gp, io_ticks)),
631 jiffies_to_msecs(disk_stat_read(gp, time_in_queue)));
633 /* now show all non-0 size partitions of it */
634 for (n = 0; n < gp->minors - 1; n++) {
635 struct hd_struct *hd = gp->part[n];
637 if (!hd || !hd->nr_sects)
641 part_round_stats(hd);
643 seq_printf(s, "%4d %4d %s %lu %lu %llu "
644 "%u %lu %lu %llu %u %u %u %u\n",
645 gp->major, n + gp->first_minor + 1,
646 disk_name(gp, n + 1, buf),
647 part_stat_read(hd, ios[0]),
648 part_stat_read(hd, merges[0]),
649 (unsigned long long)part_stat_read(hd, sectors[0]),
650 jiffies_to_msecs(part_stat_read(hd, ticks[0])),
651 part_stat_read(hd, ios[1]),
652 part_stat_read(hd, merges[1]),
653 (unsigned long long)part_stat_read(hd, sectors[1]),
654 jiffies_to_msecs(part_stat_read(hd, ticks[1])),
656 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
657 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
664 const struct seq_operations diskstats_op = {
665 .start = diskstats_start,
666 .next = diskstats_next,
667 .stop = diskstats_stop,
668 .show = diskstats_show
670 #endif /* CONFIG_PROC_FS */
672 static void media_change_notify_thread(struct work_struct *work)
674 struct gendisk *gd = container_of(work, struct gendisk, async_notify);
675 char event[] = "MEDIA_CHANGE=1";
676 char *envp[] = { event, NULL };
679 * set enviroment vars to indicate which event this is for
680 * so that user space will know to go check the media status.
682 kobject_uevent_env(&gd->dev.kobj, KOBJ_CHANGE, envp);
683 put_device(gd->driverfs_dev);
687 void genhd_media_change_notify(struct gendisk *disk)
689 get_device(disk->driverfs_dev);
690 schedule_work(&disk->async_notify);
692 EXPORT_SYMBOL_GPL(genhd_media_change_notify);
700 static int match_id(struct device *dev, void *data)
702 struct find_block *find = data;
704 if (dev->type != &disk_type)
706 if (strcmp(dev->bus_id, find->name) == 0) {
707 struct gendisk *disk = dev_to_disk(dev);
708 if (find->part < disk->minors)
714 dev_t blk_lookup_devt(const char *name, int part)
717 dev_t devt = MKDEV(0, 0);
718 struct find_block find;
720 mutex_lock(&block_class_lock);
723 dev = class_find_device(&block_class, NULL, &find, match_id);
726 devt = MKDEV(MAJOR(dev->devt),
727 MINOR(dev->devt) + part);
729 mutex_unlock(&block_class_lock);
733 EXPORT_SYMBOL(blk_lookup_devt);
735 struct gendisk *alloc_disk(int minors)
737 return alloc_disk_node(minors, -1);
740 struct gendisk *alloc_disk_node(int minors, int node_id)
742 struct gendisk *disk;
744 disk = kmalloc_node(sizeof(struct gendisk),
745 GFP_KERNEL | __GFP_ZERO, node_id);
747 if (!init_disk_stats(disk)) {
752 int size = (minors - 1) * sizeof(struct hd_struct *);
753 disk->part = kmalloc_node(size,
754 GFP_KERNEL | __GFP_ZERO, node_id);
756 free_disk_stats(disk);
761 disk->minors = minors;
762 rand_initialize_disk(disk);
763 disk->dev.class = &block_class;
764 disk->dev.type = &disk_type;
765 device_initialize(&disk->dev);
766 INIT_WORK(&disk->async_notify,
767 media_change_notify_thread);
772 EXPORT_SYMBOL(alloc_disk);
773 EXPORT_SYMBOL(alloc_disk_node);
775 struct kobject *get_disk(struct gendisk *disk)
777 struct module *owner;
778 struct kobject *kobj;
782 owner = disk->fops->owner;
783 if (owner && !try_module_get(owner))
785 kobj = kobject_get(&disk->dev.kobj);
794 EXPORT_SYMBOL(get_disk);
796 void put_disk(struct gendisk *disk)
799 kobject_put(&disk->dev.kobj);
802 EXPORT_SYMBOL(put_disk);
804 void set_device_ro(struct block_device *bdev, int flag)
806 if (bdev->bd_contains != bdev)
807 bdev->bd_part->policy = flag;
809 bdev->bd_disk->policy = flag;
812 EXPORT_SYMBOL(set_device_ro);
814 void set_disk_ro(struct gendisk *disk, int flag)
818 for (i = 0; i < disk->minors - 1; i++)
819 if (disk->part[i]) disk->part[i]->policy = flag;
822 EXPORT_SYMBOL(set_disk_ro);
824 int bdev_read_only(struct block_device *bdev)
828 else if (bdev->bd_contains != bdev)
829 return bdev->bd_part->policy;
831 return bdev->bd_disk->policy;
834 EXPORT_SYMBOL(bdev_read_only);
836 int invalidate_partition(struct gendisk *disk, int index)
839 struct block_device *bdev = bdget_disk(disk, index);
842 res = __invalidate_device(bdev);
848 EXPORT_SYMBOL(invalidate_partition);