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_ro_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
243 struct hd_struct *p = dev_to_part(dev);
244 return sprintf(buf, "%d\n", p->policy ? 1 : 0);
247 ssize_t part_alignment_offset_show(struct device *dev,
248 struct device_attribute *attr, char *buf)
250 struct hd_struct *p = dev_to_part(dev);
251 return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
254 ssize_t part_discard_alignment_show(struct device *dev,
255 struct device_attribute *attr, char *buf)
257 struct hd_struct *p = dev_to_part(dev);
258 return sprintf(buf, "%u\n", p->discard_alignment);
261 ssize_t part_stat_show(struct device *dev,
262 struct device_attribute *attr, char *buf)
264 struct hd_struct *p = dev_to_part(dev);
267 cpu = part_stat_lock();
268 part_round_stats(cpu, p);
271 "%8lu %8lu %8llu %8u "
272 "%8lu %8lu %8llu %8u "
275 part_stat_read(p, ios[READ]),
276 part_stat_read(p, merges[READ]),
277 (unsigned long long)part_stat_read(p, sectors[READ]),
278 jiffies_to_msecs(part_stat_read(p, ticks[READ])),
279 part_stat_read(p, ios[WRITE]),
280 part_stat_read(p, merges[WRITE]),
281 (unsigned long long)part_stat_read(p, sectors[WRITE]),
282 jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
284 jiffies_to_msecs(part_stat_read(p, io_ticks)),
285 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
288 ssize_t part_inflight_show(struct device *dev,
289 struct device_attribute *attr, char *buf)
291 struct hd_struct *p = dev_to_part(dev);
293 return sprintf(buf, "%8u %8u\n", p->in_flight[0], p->in_flight[1]);
296 #ifdef CONFIG_FAIL_MAKE_REQUEST
297 ssize_t part_fail_show(struct device *dev,
298 struct device_attribute *attr, char *buf)
300 struct hd_struct *p = dev_to_part(dev);
302 return sprintf(buf, "%d\n", p->make_it_fail);
305 ssize_t part_fail_store(struct device *dev,
306 struct device_attribute *attr,
307 const char *buf, size_t count)
309 struct hd_struct *p = dev_to_part(dev);
312 if (count > 0 && sscanf(buf, "%d", &i) > 0)
313 p->make_it_fail = (i == 0) ? 0 : 1;
319 static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
320 static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
321 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
322 static DEVICE_ATTR(ro, S_IRUGO, part_ro_show, NULL);
323 static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
324 static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
326 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
327 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
328 #ifdef CONFIG_FAIL_MAKE_REQUEST
329 static struct device_attribute dev_attr_fail =
330 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
333 static struct attribute *part_attrs[] = {
334 &dev_attr_partition.attr,
335 &dev_attr_start.attr,
338 &dev_attr_alignment_offset.attr,
339 &dev_attr_discard_alignment.attr,
341 &dev_attr_inflight.attr,
342 #ifdef CONFIG_FAIL_MAKE_REQUEST
348 static struct attribute_group part_attr_group = {
352 static const struct attribute_group *part_attr_groups[] = {
354 #ifdef CONFIG_BLK_DEV_IO_TRACE
355 &blk_trace_attr_group,
360 static void part_release(struct device *dev)
362 struct hd_struct *p = dev_to_part(dev);
368 struct device_type part_type = {
370 .groups = part_attr_groups,
371 .release = part_release,
374 static void delete_partition_rcu_cb(struct rcu_head *head)
376 struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
378 part->start_sect = 0;
380 part_stat_set_all(part, 0);
381 put_device(part_to_dev(part));
384 void __delete_partition(struct hd_struct *part)
386 call_rcu(&part->rcu_head, delete_partition_rcu_cb);
389 void delete_partition(struct gendisk *disk, int partno)
391 struct disk_part_tbl *ptbl = disk->part_tbl;
392 struct hd_struct *part;
394 if (partno >= ptbl->len)
397 part = ptbl->part[partno];
401 blk_free_devt(part_devt(part));
402 rcu_assign_pointer(ptbl->part[partno], NULL);
403 rcu_assign_pointer(ptbl->last_lookup, NULL);
404 kobject_put(part->holder_dir);
405 device_del(part_to_dev(part));
410 static ssize_t whole_disk_show(struct device *dev,
411 struct device_attribute *attr, char *buf)
415 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
416 whole_disk_show, NULL);
418 struct hd_struct *add_partition(struct gendisk *disk, int partno,
419 sector_t start, sector_t len, int flags,
420 struct partition_meta_info *info)
423 dev_t devt = MKDEV(0, 0);
424 struct device *ddev = disk_to_dev(disk);
426 struct disk_part_tbl *ptbl;
430 err = disk_expand_part_tbl(disk, partno);
433 ptbl = disk->part_tbl;
435 if (ptbl->part[partno])
436 return ERR_PTR(-EBUSY);
438 p = kzalloc(sizeof(*p), GFP_KERNEL);
440 return ERR_PTR(-EBUSY);
442 if (!init_part_stats(p)) {
446 pdev = part_to_dev(p);
448 p->start_sect = start;
449 p->alignment_offset =
450 queue_limit_alignment_offset(&disk->queue->limits, start);
451 p->discard_alignment =
452 queue_limit_discard_alignment(&disk->queue->limits, start);
455 p->policy = get_disk_ro(disk);
458 struct partition_meta_info *pinfo = alloc_part_info(disk);
461 memcpy(pinfo, info, sizeof(*info));
465 dname = dev_name(ddev);
466 if (isdigit(dname[strlen(dname) - 1]))
467 dev_set_name(pdev, "%sp%d", dname, partno);
469 dev_set_name(pdev, "%s%d", dname, partno);
471 device_initialize(pdev);
472 pdev->class = &block_class;
473 pdev->type = &part_type;
476 err = blk_alloc_devt(p, &devt);
481 /* delay uevent until 'holders' subdir is created */
482 dev_set_uevent_suppress(pdev, 1);
483 err = device_add(pdev);
488 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
492 dev_set_uevent_suppress(pdev, 0);
493 if (flags & ADDPART_FLAG_WHOLEDISK) {
494 err = device_create_file(pdev, &dev_attr_whole_disk);
499 /* everything is up and running, commence */
500 rcu_assign_pointer(ptbl->part[partno], p);
502 /* suppress uevent if the disk supresses it */
503 if (!dev_get_uevent_suppress(ddev))
504 kobject_uevent(&pdev->kobj, KOBJ_ADD);
517 kobject_put(p->holder_dir);
525 /* Not exported, helper to add_disk(). */
526 void register_disk(struct gendisk *disk)
528 struct device *ddev = disk_to_dev(disk);
529 struct block_device *bdev;
530 struct disk_part_iter piter;
531 struct hd_struct *part;
534 ddev->parent = disk->driverfs_dev;
536 dev_set_name(ddev, disk->disk_name);
538 /* delay uevents, until we scanned partition table */
539 dev_set_uevent_suppress(ddev, 1);
541 if (device_add(ddev))
543 if (!sysfs_deprecated) {
544 err = sysfs_create_link(block_depr, &ddev->kobj,
545 kobject_name(&ddev->kobj));
551 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
552 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
554 /* No minors to use for partitions */
555 if (!disk_partitionable(disk))
558 /* No such device (e.g., media were just removed) */
559 if (!get_capacity(disk))
562 bdev = bdget_disk(disk, 0);
566 bdev->bd_invalidated = 1;
567 err = blkdev_get(bdev, FMODE_READ, NULL);
570 blkdev_put(bdev, FMODE_READ);
573 /* announce disk after possible partitions are created */
574 dev_set_uevent_suppress(ddev, 0);
575 kobject_uevent(&ddev->kobj, KOBJ_ADD);
577 /* announce possible partitions */
578 disk_part_iter_init(&piter, disk, 0);
579 while ((part = disk_part_iter_next(&piter)))
580 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
581 disk_part_iter_exit(&piter);
584 static bool disk_unlock_native_capacity(struct gendisk *disk)
586 const struct block_device_operations *bdops = disk->fops;
588 if (bdops->unlock_native_capacity &&
589 !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
590 printk(KERN_CONT "enabling native capacity\n");
591 bdops->unlock_native_capacity(disk);
592 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
595 printk(KERN_CONT "truncated\n");
600 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
602 struct parsed_partitions *state = NULL;
603 struct disk_part_iter piter;
604 struct hd_struct *part;
607 if (state && !IS_ERR(state)) {
612 if (bdev->bd_part_count)
614 res = invalidate_partition(disk, 0);
618 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
619 while ((part = disk_part_iter_next(&piter)))
620 delete_partition(disk, part->partno);
621 disk_part_iter_exit(&piter);
623 if (disk->fops->revalidate_disk)
624 disk->fops->revalidate_disk(disk);
625 check_disk_size_change(disk, bdev);
626 bdev->bd_invalidated = 0;
627 if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
631 * I/O error reading the partition table. If any
632 * partition code tried to read beyond EOD, retry
633 * after unlocking native capacity.
635 if (PTR_ERR(state) == -ENOSPC) {
636 printk(KERN_WARNING "%s: partition table beyond EOD, ",
638 if (disk_unlock_native_capacity(disk))
644 * If any partition code tried to read beyond EOD, try
645 * unlocking native capacity even if partition table is
646 * sucessfully read as we could be missing some partitions.
648 if (state->access_beyond_eod) {
650 "%s: partition table partially beyond EOD, ",
652 if (disk_unlock_native_capacity(disk))
656 /* tell userspace that the media / partition table may have changed */
657 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
659 /* Detect the highest partition number and preallocate
660 * disk->part_tbl. This is an optimization and not strictly
663 for (p = 1, highest = 0; p < state->limit; p++)
664 if (state->parts[p].size)
667 disk_expand_part_tbl(disk, highest);
670 for (p = 1; p < state->limit; p++) {
672 struct partition_meta_info *info = NULL;
674 size = state->parts[p].size;
678 from = state->parts[p].from;
679 if (from >= get_capacity(disk)) {
681 "%s: p%d start %llu is beyond EOD, ",
682 disk->disk_name, p, (unsigned long long) from);
683 if (disk_unlock_native_capacity(disk))
688 if (from + size > get_capacity(disk)) {
690 "%s: p%d size %llu extends beyond EOD, ",
691 disk->disk_name, p, (unsigned long long) size);
693 if (disk_unlock_native_capacity(disk)) {
694 /* free state and restart */
698 * we can not ignore partitions of broken tables
699 * created by for example camera firmware, but
700 * we limit them to the end of the disk to avoid
701 * creating invalid block devices
703 size = get_capacity(disk) - from;
707 if (state->parts[p].has_info)
708 info = &state->parts[p].info;
709 part = add_partition(disk, p, from, size,
710 state->parts[p].flags,
711 &state->parts[p].info);
713 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
714 disk->disk_name, p, -PTR_ERR(part));
717 #ifdef CONFIG_BLK_DEV_MD
718 if (state->parts[p].flags & ADDPART_FLAG_RAID)
719 md_autodetect_dev(part_to_dev(part)->devt);
726 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
728 struct address_space *mapping = bdev->bd_inode->i_mapping;
731 page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
737 return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
739 page_cache_release(page);
745 EXPORT_SYMBOL(read_dev_sector);
747 void del_gendisk(struct gendisk *disk)
749 struct disk_part_iter piter;
750 struct hd_struct *part;
752 /* invalidate stuff */
753 disk_part_iter_init(&piter, disk,
754 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
755 while ((part = disk_part_iter_next(&piter))) {
756 invalidate_partition(disk, part->partno);
757 delete_partition(disk, part->partno);
759 disk_part_iter_exit(&piter);
761 invalidate_partition(disk, 0);
762 blk_free_devt(disk_to_dev(disk)->devt);
763 set_capacity(disk, 0);
764 disk->flags &= ~GENHD_FL_UP;
765 unlink_gendisk(disk);
766 part_stat_set_all(&disk->part0, 0);
767 disk->part0.stamp = 0;
769 kobject_put(disk->part0.holder_dir);
770 kobject_put(disk->slave_dir);
771 disk->driverfs_dev = NULL;
772 if (!sysfs_deprecated)
773 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
774 device_del(disk_to_dev(disk));