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);
167 state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
168 if (!state->pp_buf) {
172 state->pp_buf[0] = '\0';
175 disk_name(hd, 0, state->name);
176 snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
177 if (isdigit(state->name[strlen(state->name)-1]))
178 sprintf(state->name, "p");
180 state->limit = disk_max_parts(hd);
182 while (!res && check_part[i]) {
183 memset(&state->parts, 0, sizeof(state->parts));
184 res = check_part[i++](state);
186 /* We have hit an I/O error which we don't report now.
187 * But record it, and let the others do their job.
195 printk(KERN_INFO "%s", state->pp_buf);
197 free_page((unsigned long)state->pp_buf);
200 if (state->access_beyond_eod)
203 /* The partition is unrecognized. So report I/O errors if there were any */
206 strlcat(state->pp_buf, " unknown partition table\n", PAGE_SIZE);
207 else if (warn_no_part)
208 strlcat(state->pp_buf, " unable to read partition table\n", PAGE_SIZE);
210 printk(KERN_INFO "%s", state->pp_buf);
212 free_page((unsigned long)state->pp_buf);
217 static ssize_t part_partition_show(struct device *dev,
218 struct device_attribute *attr, char *buf)
220 struct hd_struct *p = dev_to_part(dev);
222 return sprintf(buf, "%d\n", p->partno);
225 static ssize_t part_start_show(struct device *dev,
226 struct device_attribute *attr, char *buf)
228 struct hd_struct *p = dev_to_part(dev);
230 return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
233 ssize_t part_size_show(struct device *dev,
234 struct device_attribute *attr, char *buf)
236 struct hd_struct *p = dev_to_part(dev);
237 return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
240 ssize_t part_alignment_offset_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
243 struct hd_struct *p = dev_to_part(dev);
244 return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
247 ssize_t part_discard_alignment_show(struct device *dev,
248 struct device_attribute *attr, char *buf)
250 struct hd_struct *p = dev_to_part(dev);
251 return sprintf(buf, "%u\n", p->discard_alignment);
254 ssize_t part_stat_show(struct device *dev,
255 struct device_attribute *attr, char *buf)
257 struct hd_struct *p = dev_to_part(dev);
260 cpu = part_stat_lock();
261 part_round_stats(cpu, p);
264 "%8lu %8lu %8llu %8u "
265 "%8lu %8lu %8llu %8u "
268 part_stat_read(p, ios[READ]),
269 part_stat_read(p, merges[READ]),
270 (unsigned long long)part_stat_read(p, sectors[READ]),
271 jiffies_to_msecs(part_stat_read(p, ticks[READ])),
272 part_stat_read(p, ios[WRITE]),
273 part_stat_read(p, merges[WRITE]),
274 (unsigned long long)part_stat_read(p, sectors[WRITE]),
275 jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
277 jiffies_to_msecs(part_stat_read(p, io_ticks)),
278 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
281 ssize_t part_inflight_show(struct device *dev,
282 struct device_attribute *attr, char *buf)
284 struct hd_struct *p = dev_to_part(dev);
286 return sprintf(buf, "%8u %8u\n", p->in_flight[0], p->in_flight[1]);
289 #ifdef CONFIG_FAIL_MAKE_REQUEST
290 ssize_t part_fail_show(struct device *dev,
291 struct device_attribute *attr, char *buf)
293 struct hd_struct *p = dev_to_part(dev);
295 return sprintf(buf, "%d\n", p->make_it_fail);
298 ssize_t part_fail_store(struct device *dev,
299 struct device_attribute *attr,
300 const char *buf, size_t count)
302 struct hd_struct *p = dev_to_part(dev);
305 if (count > 0 && sscanf(buf, "%d", &i) > 0)
306 p->make_it_fail = (i == 0) ? 0 : 1;
312 static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
313 static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
314 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
315 static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
316 static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
318 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
319 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
320 #ifdef CONFIG_FAIL_MAKE_REQUEST
321 static struct device_attribute dev_attr_fail =
322 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
325 static struct attribute *part_attrs[] = {
326 &dev_attr_partition.attr,
327 &dev_attr_start.attr,
329 &dev_attr_alignment_offset.attr,
330 &dev_attr_discard_alignment.attr,
332 &dev_attr_inflight.attr,
333 #ifdef CONFIG_FAIL_MAKE_REQUEST
339 static struct attribute_group part_attr_group = {
343 static const struct attribute_group *part_attr_groups[] = {
345 #ifdef CONFIG_BLK_DEV_IO_TRACE
346 &blk_trace_attr_group,
351 static void part_release(struct device *dev)
353 struct hd_struct *p = dev_to_part(dev);
358 struct device_type part_type = {
360 .groups = part_attr_groups,
361 .release = part_release,
364 static void delete_partition_rcu_cb(struct rcu_head *head)
366 struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
368 part->start_sect = 0;
370 part_stat_set_all(part, 0);
371 put_device(part_to_dev(part));
374 void delete_partition(struct gendisk *disk, int partno)
376 struct disk_part_tbl *ptbl = disk->part_tbl;
377 struct hd_struct *part;
379 if (partno >= ptbl->len)
382 part = ptbl->part[partno];
386 blk_free_devt(part_devt(part));
387 rcu_assign_pointer(ptbl->part[partno], NULL);
388 rcu_assign_pointer(ptbl->last_lookup, NULL);
389 kobject_put(part->holder_dir);
390 device_del(part_to_dev(part));
392 call_rcu(&part->rcu_head, delete_partition_rcu_cb);
395 static ssize_t whole_disk_show(struct device *dev,
396 struct device_attribute *attr, char *buf)
400 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
401 whole_disk_show, NULL);
403 struct hd_struct *add_partition(struct gendisk *disk, int partno,
404 sector_t start, sector_t len, int flags)
407 dev_t devt = MKDEV(0, 0);
408 struct device *ddev = disk_to_dev(disk);
410 struct disk_part_tbl *ptbl;
414 err = disk_expand_part_tbl(disk, partno);
417 ptbl = disk->part_tbl;
419 if (ptbl->part[partno])
420 return ERR_PTR(-EBUSY);
422 p = kzalloc(sizeof(*p), GFP_KERNEL);
424 return ERR_PTR(-EBUSY);
426 if (!init_part_stats(p)) {
430 pdev = part_to_dev(p);
432 p->start_sect = start;
433 p->alignment_offset =
434 queue_limit_alignment_offset(&disk->queue->limits, start);
435 p->discard_alignment =
436 queue_limit_discard_alignment(&disk->queue->limits, start);
439 p->policy = get_disk_ro(disk);
441 dname = dev_name(ddev);
442 if (isdigit(dname[strlen(dname) - 1]))
443 dev_set_name(pdev, "%sp%d", dname, partno);
445 dev_set_name(pdev, "%s%d", dname, partno);
447 device_initialize(pdev);
448 pdev->class = &block_class;
449 pdev->type = &part_type;
452 err = blk_alloc_devt(p, &devt);
457 /* delay uevent until 'holders' subdir is created */
458 dev_set_uevent_suppress(pdev, 1);
459 err = device_add(pdev);
464 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
468 dev_set_uevent_suppress(pdev, 0);
469 if (flags & ADDPART_FLAG_WHOLEDISK) {
470 err = device_create_file(pdev, &dev_attr_whole_disk);
475 /* everything is up and running, commence */
476 rcu_assign_pointer(ptbl->part[partno], p);
478 /* suppress uevent if the disk supresses it */
479 if (!dev_get_uevent_suppress(ddev))
480 kobject_uevent(&pdev->kobj, KOBJ_ADD);
490 kobject_put(p->holder_dir);
498 /* Not exported, helper to add_disk(). */
499 void register_disk(struct gendisk *disk)
501 struct device *ddev = disk_to_dev(disk);
502 struct block_device *bdev;
503 struct disk_part_iter piter;
504 struct hd_struct *part;
507 ddev->parent = disk->driverfs_dev;
509 dev_set_name(ddev, disk->disk_name);
511 /* delay uevents, until we scanned partition table */
512 dev_set_uevent_suppress(ddev, 1);
514 if (device_add(ddev))
516 #ifndef CONFIG_SYSFS_DEPRECATED
517 err = sysfs_create_link(block_depr, &ddev->kobj,
518 kobject_name(&ddev->kobj));
524 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
525 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
527 /* No minors to use for partitions */
528 if (!disk_partitionable(disk))
531 /* No such device (e.g., media were just removed) */
532 if (!get_capacity(disk))
535 bdev = bdget_disk(disk, 0);
539 bdev->bd_invalidated = 1;
540 err = blkdev_get(bdev, FMODE_READ);
543 blkdev_put(bdev, FMODE_READ);
546 /* announce disk after possible partitions are created */
547 dev_set_uevent_suppress(ddev, 0);
548 kobject_uevent(&ddev->kobj, KOBJ_ADD);
550 /* announce possible partitions */
551 disk_part_iter_init(&piter, disk, 0);
552 while ((part = disk_part_iter_next(&piter)))
553 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
554 disk_part_iter_exit(&piter);
557 static bool disk_unlock_native_capacity(struct gendisk *disk)
559 const struct block_device_operations *bdops = disk->fops;
561 if (bdops->unlock_native_capacity &&
562 !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
563 printk(KERN_CONT "enabling native capacity\n");
564 bdops->unlock_native_capacity(disk);
565 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
568 printk(KERN_CONT "truncated\n");
573 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
575 struct parsed_partitions *state = NULL;
576 struct disk_part_iter piter;
577 struct hd_struct *part;
580 if (state && !IS_ERR(state)) {
585 if (bdev->bd_part_count)
587 res = invalidate_partition(disk, 0);
591 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
592 while ((part = disk_part_iter_next(&piter)))
593 delete_partition(disk, part->partno);
594 disk_part_iter_exit(&piter);
596 if (disk->fops->revalidate_disk)
597 disk->fops->revalidate_disk(disk);
598 check_disk_size_change(disk, bdev);
599 bdev->bd_invalidated = 0;
600 if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
604 * I/O error reading the partition table. If any
605 * partition code tried to read beyond EOD, retry
606 * after unlocking native capacity.
608 if (PTR_ERR(state) == -ENOSPC) {
609 printk(KERN_WARNING "%s: partition table beyond EOD, ",
611 if (disk_unlock_native_capacity(disk))
617 * If any partition code tried to read beyond EOD, try
618 * unlocking native capacity even if partition table is
619 * sucessfully read as we could be missing some partitions.
621 if (state->access_beyond_eod) {
623 "%s: partition table partially beyond EOD, ",
625 if (disk_unlock_native_capacity(disk))
629 /* tell userspace that the media / partition table may have changed */
630 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
632 /* Detect the highest partition number and preallocate
633 * disk->part_tbl. This is an optimization and not strictly
636 for (p = 1, highest = 0; p < state->limit; p++)
637 if (state->parts[p].size)
640 disk_expand_part_tbl(disk, highest);
643 for (p = 1; p < state->limit; p++) {
646 size = state->parts[p].size;
650 from = state->parts[p].from;
651 if (from >= get_capacity(disk)) {
653 "%s: p%d start %llu is beyond EOD, ",
654 disk->disk_name, p, (unsigned long long) from);
655 if (disk_unlock_native_capacity(disk))
660 if (from + size > get_capacity(disk)) {
662 "%s: p%d size %llu extends beyond EOD, ",
663 disk->disk_name, p, (unsigned long long) size);
665 if (disk_unlock_native_capacity(disk)) {
666 /* free state and restart */
670 * we can not ignore partitions of broken tables
671 * created by for example camera firmware, but
672 * we limit them to the end of the disk to avoid
673 * creating invalid block devices
675 size = get_capacity(disk) - from;
678 part = add_partition(disk, p, from, size,
679 state->parts[p].flags);
681 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
682 disk->disk_name, p, -PTR_ERR(part));
685 #ifdef CONFIG_BLK_DEV_MD
686 if (state->parts[p].flags & ADDPART_FLAG_RAID)
687 md_autodetect_dev(part_to_dev(part)->devt);
694 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
696 struct address_space *mapping = bdev->bd_inode->i_mapping;
699 page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
705 return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
707 page_cache_release(page);
713 EXPORT_SYMBOL(read_dev_sector);
715 void del_gendisk(struct gendisk *disk)
717 struct disk_part_iter piter;
718 struct hd_struct *part;
720 /* invalidate stuff */
721 disk_part_iter_init(&piter, disk,
722 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
723 while ((part = disk_part_iter_next(&piter))) {
724 invalidate_partition(disk, part->partno);
725 delete_partition(disk, part->partno);
727 disk_part_iter_exit(&piter);
729 invalidate_partition(disk, 0);
730 blk_free_devt(disk_to_dev(disk)->devt);
731 set_capacity(disk, 0);
732 disk->flags &= ~GENHD_FL_UP;
733 unlink_gendisk(disk);
734 part_stat_set_all(&disk->part0, 0);
735 disk->part0.stamp = 0;
737 kobject_put(disk->part0.holder_dir);
738 kobject_put(disk->slave_dir);
739 disk->driverfs_dev = NULL;
740 #ifndef CONFIG_SYSFS_DEPRECATED
741 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
743 device_del(disk_to_dev(disk));