2 * fs/partitions/check.c
4 * Code extracted from drivers/block/genhd.c
5 * Copyright (C) 1991-1998 Linus Torvalds
6 * Re-organised Feb 1998 Russell King
8 * We now have independent partition support from the
9 * block drivers, which allows all the partition code to
10 * be grouped in one location, and it to be mostly self
13 * Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
16 #include <linux/init.h>
17 #include <linux/module.h>
19 #include <linux/slab.h>
20 #include <linux/kmod.h>
21 #include <linux/ctype.h>
22 #include <linux/genhd.h>
23 #include <linux/blktrace_api.h>
42 #ifdef CONFIG_BLK_DEV_MD
43 extern void md_autodetect_dev(dev_t dev);
46 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
48 static int (*check_part[])(struct parsed_partitions *) = {
50 * Probe partition formats with tables at disk address 0
51 * that also have an ADFS boot block at 0xdc0.
53 #ifdef CONFIG_ACORN_PARTITION_ICS
56 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
57 adfspart_check_POWERTEC,
59 #ifdef CONFIG_ACORN_PARTITION_EESOX
64 * Now move on to formats that only have partition info at
65 * disk address 0xdc0. Since these may also have stale
66 * PC/BIOS partition tables, they need to come before
69 #ifdef CONFIG_ACORN_PARTITION_CUMANA
70 adfspart_check_CUMANA,
72 #ifdef CONFIG_ACORN_PARTITION_ADFS
76 #ifdef CONFIG_EFI_PARTITION
77 efi_partition, /* this must come before msdos */
79 #ifdef CONFIG_SGI_PARTITION
82 #ifdef CONFIG_LDM_PARTITION
83 ldm_partition, /* this must come before msdos */
85 #ifdef CONFIG_MSDOS_PARTITION
88 #ifdef CONFIG_OSF_PARTITION
91 #ifdef CONFIG_SUN_PARTITION
94 #ifdef CONFIG_AMIGA_PARTITION
97 #ifdef CONFIG_ATARI_PARTITION
100 #ifdef CONFIG_MAC_PARTITION
103 #ifdef CONFIG_ULTRIX_PARTITION
106 #ifdef CONFIG_IBM_PARTITION
109 #ifdef CONFIG_KARMA_PARTITION
112 #ifdef CONFIG_SYSV68_PARTITION
119 * disk_name() is used by partition check code and the genhd driver.
120 * It formats the devicename of the indicated disk into
121 * the supplied buffer (of size at least 32), and returns
122 * a pointer to that same buffer (for convenience).
125 char *disk_name(struct gendisk *hd, int partno, char *buf)
128 snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
129 else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
130 snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
132 snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
137 const char *bdevname(struct block_device *bdev, char *buf)
139 return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
142 EXPORT_SYMBOL(bdevname);
145 * There's very little reason to use this, you should really
146 * have a struct block_device just about everywhere and use
147 * bdevname() instead.
149 const char *__bdevname(dev_t dev, char *buffer)
151 scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
152 MAJOR(dev), MINOR(dev));
156 EXPORT_SYMBOL(__bdevname);
158 static struct parsed_partitions *
159 check_partition(struct gendisk *hd, struct block_device *bdev)
161 struct parsed_partitions *state;
164 state = kzalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
169 disk_name(hd, 0, state->name);
170 printk(KERN_INFO " %s:", state->name);
171 if (isdigit(state->name[strlen(state->name)-1]))
172 sprintf(state->name, "p");
174 state->limit = disk_max_parts(hd);
176 while (!res && check_part[i]) {
177 memset(&state->parts, 0, sizeof(state->parts));
178 res = check_part[i++](state);
180 /* We have hit an I/O error which we don't report now.
181 * But record it, and let the others do their job.
190 if (state->access_beyond_eod)
193 /* The partition is unrecognized. So report I/O errors if there were any */
196 printk(" unknown partition table\n");
197 else if (warn_no_part)
198 printk(" unable to read partition table\n");
203 static ssize_t part_partition_show(struct device *dev,
204 struct device_attribute *attr, char *buf)
206 struct hd_struct *p = dev_to_part(dev);
208 return sprintf(buf, "%d\n", p->partno);
211 static ssize_t part_start_show(struct device *dev,
212 struct device_attribute *attr, char *buf)
214 struct hd_struct *p = dev_to_part(dev);
216 return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
219 ssize_t part_size_show(struct device *dev,
220 struct device_attribute *attr, char *buf)
222 struct hd_struct *p = dev_to_part(dev);
223 return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
226 ssize_t part_alignment_offset_show(struct device *dev,
227 struct device_attribute *attr, char *buf)
229 struct hd_struct *p = dev_to_part(dev);
230 return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
233 ssize_t part_discard_alignment_show(struct device *dev,
234 struct device_attribute *attr, char *buf)
236 struct hd_struct *p = dev_to_part(dev);
237 return sprintf(buf, "%u\n", p->discard_alignment);
240 ssize_t part_stat_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
243 struct hd_struct *p = dev_to_part(dev);
246 cpu = part_stat_lock();
247 part_round_stats(cpu, p);
250 "%8lu %8lu %8llu %8u "
251 "%8lu %8lu %8llu %8u "
254 part_stat_read(p, ios[READ]),
255 part_stat_read(p, merges[READ]),
256 (unsigned long long)part_stat_read(p, sectors[READ]),
257 jiffies_to_msecs(part_stat_read(p, ticks[READ])),
258 part_stat_read(p, ios[WRITE]),
259 part_stat_read(p, merges[WRITE]),
260 (unsigned long long)part_stat_read(p, sectors[WRITE]),
261 jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
263 jiffies_to_msecs(part_stat_read(p, io_ticks)),
264 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
267 ssize_t part_inflight_show(struct device *dev,
268 struct device_attribute *attr, char *buf)
270 struct hd_struct *p = dev_to_part(dev);
272 return sprintf(buf, "%8u %8u\n", p->in_flight[0], p->in_flight[1]);
275 #ifdef CONFIG_FAIL_MAKE_REQUEST
276 ssize_t part_fail_show(struct device *dev,
277 struct device_attribute *attr, char *buf)
279 struct hd_struct *p = dev_to_part(dev);
281 return sprintf(buf, "%d\n", p->make_it_fail);
284 ssize_t part_fail_store(struct device *dev,
285 struct device_attribute *attr,
286 const char *buf, size_t count)
288 struct hd_struct *p = dev_to_part(dev);
291 if (count > 0 && sscanf(buf, "%d", &i) > 0)
292 p->make_it_fail = (i == 0) ? 0 : 1;
298 static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
299 static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
300 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
301 static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
302 static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
304 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
305 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
306 #ifdef CONFIG_FAIL_MAKE_REQUEST
307 static struct device_attribute dev_attr_fail =
308 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
311 static struct attribute *part_attrs[] = {
312 &dev_attr_partition.attr,
313 &dev_attr_start.attr,
315 &dev_attr_alignment_offset.attr,
316 &dev_attr_discard_alignment.attr,
318 &dev_attr_inflight.attr,
319 #ifdef CONFIG_FAIL_MAKE_REQUEST
325 static struct attribute_group part_attr_group = {
329 static const struct attribute_group *part_attr_groups[] = {
331 #ifdef CONFIG_BLK_DEV_IO_TRACE
332 &blk_trace_attr_group,
337 static void part_release(struct device *dev)
339 struct hd_struct *p = dev_to_part(dev);
344 struct device_type part_type = {
346 .groups = part_attr_groups,
347 .release = part_release,
350 static void delete_partition_rcu_cb(struct rcu_head *head)
352 struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
354 part->start_sect = 0;
356 part_stat_set_all(part, 0);
357 put_device(part_to_dev(part));
360 void delete_partition(struct gendisk *disk, int partno)
362 struct disk_part_tbl *ptbl = disk->part_tbl;
363 struct hd_struct *part;
365 if (partno >= ptbl->len)
368 part = ptbl->part[partno];
372 blk_free_devt(part_devt(part));
373 rcu_assign_pointer(ptbl->part[partno], NULL);
374 rcu_assign_pointer(ptbl->last_lookup, NULL);
375 kobject_put(part->holder_dir);
376 device_del(part_to_dev(part));
378 call_rcu(&part->rcu_head, delete_partition_rcu_cb);
381 static ssize_t whole_disk_show(struct device *dev,
382 struct device_attribute *attr, char *buf)
386 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
387 whole_disk_show, NULL);
389 struct hd_struct *add_partition(struct gendisk *disk, int partno,
390 sector_t start, sector_t len, int flags)
393 dev_t devt = MKDEV(0, 0);
394 struct device *ddev = disk_to_dev(disk);
396 struct disk_part_tbl *ptbl;
400 err = disk_expand_part_tbl(disk, partno);
403 ptbl = disk->part_tbl;
405 if (ptbl->part[partno])
406 return ERR_PTR(-EBUSY);
408 p = kzalloc(sizeof(*p), GFP_KERNEL);
410 return ERR_PTR(-EBUSY);
412 if (!init_part_stats(p)) {
416 pdev = part_to_dev(p);
418 p->start_sect = start;
419 p->alignment_offset =
420 queue_limit_alignment_offset(&disk->queue->limits, start);
421 p->discard_alignment =
422 queue_limit_discard_alignment(&disk->queue->limits, start);
425 p->policy = get_disk_ro(disk);
427 dname = dev_name(ddev);
428 if (isdigit(dname[strlen(dname) - 1]))
429 dev_set_name(pdev, "%sp%d", dname, partno);
431 dev_set_name(pdev, "%s%d", dname, partno);
433 device_initialize(pdev);
434 pdev->class = &block_class;
435 pdev->type = &part_type;
438 err = blk_alloc_devt(p, &devt);
443 /* delay uevent until 'holders' subdir is created */
444 dev_set_uevent_suppress(pdev, 1);
445 err = device_add(pdev);
450 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
454 dev_set_uevent_suppress(pdev, 0);
455 if (flags & ADDPART_FLAG_WHOLEDISK) {
456 err = device_create_file(pdev, &dev_attr_whole_disk);
461 /* everything is up and running, commence */
462 INIT_RCU_HEAD(&p->rcu_head);
463 rcu_assign_pointer(ptbl->part[partno], p);
465 /* suppress uevent if the disk supresses it */
466 if (!dev_get_uevent_suppress(ddev))
467 kobject_uevent(&pdev->kobj, KOBJ_ADD);
477 kobject_put(p->holder_dir);
485 /* Not exported, helper to add_disk(). */
486 void register_disk(struct gendisk *disk)
488 struct device *ddev = disk_to_dev(disk);
489 struct block_device *bdev;
490 struct disk_part_iter piter;
491 struct hd_struct *part;
494 ddev->parent = disk->driverfs_dev;
496 dev_set_name(ddev, disk->disk_name);
498 /* delay uevents, until we scanned partition table */
499 dev_set_uevent_suppress(ddev, 1);
501 if (device_add(ddev))
503 #ifndef CONFIG_SYSFS_DEPRECATED
504 err = sysfs_create_link(block_depr, &ddev->kobj,
505 kobject_name(&ddev->kobj));
511 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
512 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
514 /* No minors to use for partitions */
515 if (!disk_partitionable(disk))
518 /* No such device (e.g., media were just removed) */
519 if (!get_capacity(disk))
522 bdev = bdget_disk(disk, 0);
526 bdev->bd_invalidated = 1;
527 err = blkdev_get(bdev, FMODE_READ);
530 blkdev_put(bdev, FMODE_READ);
533 /* announce disk after possible partitions are created */
534 dev_set_uevent_suppress(ddev, 0);
535 kobject_uevent(&ddev->kobj, KOBJ_ADD);
537 /* announce possible partitions */
538 disk_part_iter_init(&piter, disk, 0);
539 while ((part = disk_part_iter_next(&piter)))
540 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
541 disk_part_iter_exit(&piter);
544 static bool disk_unlock_native_capacity(struct gendisk *disk)
546 const struct block_device_operations *bdops = disk->fops;
548 if (bdops->unlock_native_capacity &&
549 !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
550 printk(KERN_CONT "enabling native capacity\n");
551 bdops->unlock_native_capacity(disk);
552 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
555 printk(KERN_CONT "truncated\n");
560 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
562 struct parsed_partitions *state = NULL;
563 struct disk_part_iter piter;
564 struct hd_struct *part;
567 if (state && !IS_ERR(state)) {
572 if (bdev->bd_part_count)
574 res = invalidate_partition(disk, 0);
578 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
579 while ((part = disk_part_iter_next(&piter)))
580 delete_partition(disk, part->partno);
581 disk_part_iter_exit(&piter);
583 if (disk->fops->revalidate_disk)
584 disk->fops->revalidate_disk(disk);
585 check_disk_size_change(disk, bdev);
586 bdev->bd_invalidated = 0;
587 if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
591 * I/O error reading the partition table. If any
592 * partition code tried to read beyond EOD, retry
593 * after unlocking native capacity.
595 if (PTR_ERR(state) == -ENOSPC) {
596 printk(KERN_WARNING "%s: partition table beyond EOD, ",
598 if (disk_unlock_native_capacity(disk))
604 * If any partition code tried to read beyond EOD, try
605 * unlocking native capacity even if partition table is
606 * sucessfully read as we could be missing some partitions.
608 if (state->access_beyond_eod) {
610 "%s: partition table partially beyond EOD, ",
612 if (disk_unlock_native_capacity(disk))
616 /* tell userspace that the media / partition table may have changed */
617 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
619 /* Detect the highest partition number and preallocate
620 * disk->part_tbl. This is an optimization and not strictly
623 for (p = 1, highest = 0; p < state->limit; p++)
624 if (state->parts[p].size)
627 disk_expand_part_tbl(disk, highest);
630 for (p = 1; p < state->limit; p++) {
633 size = state->parts[p].size;
637 from = state->parts[p].from;
638 if (from >= get_capacity(disk)) {
640 "%s: p%d start %llu is beyond EOD, ",
641 disk->disk_name, p, (unsigned long long) from);
642 if (disk_unlock_native_capacity(disk))
647 if (from + size > get_capacity(disk)) {
649 "%s: p%d size %llu extends beyond EOD, ",
650 disk->disk_name, p, (unsigned long long) size);
652 if (disk_unlock_native_capacity(disk)) {
653 /* free state and restart */
657 * we can not ignore partitions of broken tables
658 * created by for example camera firmware, but
659 * we limit them to the end of the disk to avoid
660 * creating invalid block devices
662 size = get_capacity(disk) - from;
665 part = add_partition(disk, p, from, size,
666 state->parts[p].flags);
668 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
669 disk->disk_name, p, -PTR_ERR(part));
672 #ifdef CONFIG_BLK_DEV_MD
673 if (state->parts[p].flags & ADDPART_FLAG_RAID)
674 md_autodetect_dev(part_to_dev(part)->devt);
681 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
683 struct address_space *mapping = bdev->bd_inode->i_mapping;
686 page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
692 return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
694 page_cache_release(page);
700 EXPORT_SYMBOL(read_dev_sector);
702 void del_gendisk(struct gendisk *disk)
704 struct disk_part_iter piter;
705 struct hd_struct *part;
707 /* invalidate stuff */
708 disk_part_iter_init(&piter, disk,
709 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
710 while ((part = disk_part_iter_next(&piter))) {
711 invalidate_partition(disk, part->partno);
712 delete_partition(disk, part->partno);
714 disk_part_iter_exit(&piter);
716 invalidate_partition(disk, 0);
717 blk_free_devt(disk_to_dev(disk)->devt);
718 set_capacity(disk, 0);
719 disk->flags &= ~GENHD_FL_UP;
720 unlink_gendisk(disk);
721 part_stat_set_all(&disk->part0, 0);
722 disk->part0.stamp = 0;
724 kobject_put(disk->part0.holder_dir);
725 kobject_put(disk->slave_dir);
726 disk->driverfs_dev = NULL;
727 #ifndef CONFIG_SYSFS_DEPRECATED
728 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
730 device_del(disk_to_dev(disk));