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 gendisk *disk, int partno)
386 struct disk_part_tbl *ptbl = disk->part_tbl;
387 struct hd_struct *part;
389 if (partno >= ptbl->len)
392 part = ptbl->part[partno];
396 blk_free_devt(part_devt(part));
397 rcu_assign_pointer(ptbl->part[partno], NULL);
398 rcu_assign_pointer(ptbl->last_lookup, NULL);
399 kobject_put(part->holder_dir);
400 device_del(part_to_dev(part));
402 call_rcu(&part->rcu_head, delete_partition_rcu_cb);
405 static ssize_t whole_disk_show(struct device *dev,
406 struct device_attribute *attr, char *buf)
410 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
411 whole_disk_show, NULL);
413 struct hd_struct *add_partition(struct gendisk *disk, int partno,
414 sector_t start, sector_t len, int flags,
415 struct partition_meta_info *info)
418 dev_t devt = MKDEV(0, 0);
419 struct device *ddev = disk_to_dev(disk);
421 struct disk_part_tbl *ptbl;
425 err = disk_expand_part_tbl(disk, partno);
428 ptbl = disk->part_tbl;
430 if (ptbl->part[partno])
431 return ERR_PTR(-EBUSY);
433 p = kzalloc(sizeof(*p), GFP_KERNEL);
435 return ERR_PTR(-EBUSY);
437 if (!init_part_stats(p)) {
441 pdev = part_to_dev(p);
443 p->start_sect = start;
444 p->alignment_offset =
445 queue_limit_alignment_offset(&disk->queue->limits, start);
446 p->discard_alignment =
447 queue_limit_discard_alignment(&disk->queue->limits, start);
450 p->policy = get_disk_ro(disk);
453 struct partition_meta_info *pinfo = alloc_part_info(disk);
456 memcpy(pinfo, info, sizeof(*info));
460 dname = dev_name(ddev);
461 if (isdigit(dname[strlen(dname) - 1]))
462 dev_set_name(pdev, "%sp%d", dname, partno);
464 dev_set_name(pdev, "%s%d", dname, partno);
466 device_initialize(pdev);
467 pdev->class = &block_class;
468 pdev->type = &part_type;
471 err = blk_alloc_devt(p, &devt);
476 /* delay uevent until 'holders' subdir is created */
477 dev_set_uevent_suppress(pdev, 1);
478 err = device_add(pdev);
483 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
487 dev_set_uevent_suppress(pdev, 0);
488 if (flags & ADDPART_FLAG_WHOLEDISK) {
489 err = device_create_file(pdev, &dev_attr_whole_disk);
494 /* everything is up and running, commence */
495 rcu_assign_pointer(ptbl->part[partno], p);
497 /* suppress uevent if the disk supresses it */
498 if (!dev_get_uevent_suppress(ddev))
499 kobject_uevent(&pdev->kobj, KOBJ_ADD);
511 kobject_put(p->holder_dir);
519 static bool disk_unlock_native_capacity(struct gendisk *disk)
521 const struct block_device_operations *bdops = disk->fops;
523 if (bdops->unlock_native_capacity &&
524 !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
525 printk(KERN_CONT "enabling native capacity\n");
526 bdops->unlock_native_capacity(disk);
527 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
530 printk(KERN_CONT "truncated\n");
535 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
537 struct parsed_partitions *state = NULL;
538 struct disk_part_iter piter;
539 struct hd_struct *part;
542 if (state && !IS_ERR(state)) {
547 if (bdev->bd_part_count)
549 res = invalidate_partition(disk, 0);
553 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
554 while ((part = disk_part_iter_next(&piter)))
555 delete_partition(disk, part->partno);
556 disk_part_iter_exit(&piter);
558 if (disk->fops->revalidate_disk)
559 disk->fops->revalidate_disk(disk);
560 check_disk_size_change(disk, bdev);
561 bdev->bd_invalidated = 0;
562 if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
566 * I/O error reading the partition table. If any
567 * partition code tried to read beyond EOD, retry
568 * after unlocking native capacity.
570 if (PTR_ERR(state) == -ENOSPC) {
571 printk(KERN_WARNING "%s: partition table beyond EOD, ",
573 if (disk_unlock_native_capacity(disk))
579 * If any partition code tried to read beyond EOD, try
580 * unlocking native capacity even if partition table is
581 * sucessfully read as we could be missing some partitions.
583 if (state->access_beyond_eod) {
585 "%s: partition table partially beyond EOD, ",
587 if (disk_unlock_native_capacity(disk))
591 /* tell userspace that the media / partition table may have changed */
592 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
594 /* Detect the highest partition number and preallocate
595 * disk->part_tbl. This is an optimization and not strictly
598 for (p = 1, highest = 0; p < state->limit; p++)
599 if (state->parts[p].size)
602 disk_expand_part_tbl(disk, highest);
605 for (p = 1; p < state->limit; p++) {
607 struct partition_meta_info *info = NULL;
609 size = state->parts[p].size;
613 from = state->parts[p].from;
614 if (from >= get_capacity(disk)) {
616 "%s: p%d start %llu is beyond EOD, ",
617 disk->disk_name, p, (unsigned long long) from);
618 if (disk_unlock_native_capacity(disk))
623 if (from + size > get_capacity(disk)) {
625 "%s: p%d size %llu extends beyond EOD, ",
626 disk->disk_name, p, (unsigned long long) size);
628 if (disk_unlock_native_capacity(disk)) {
629 /* free state and restart */
633 * we can not ignore partitions of broken tables
634 * created by for example camera firmware, but
635 * we limit them to the end of the disk to avoid
636 * creating invalid block devices
638 size = get_capacity(disk) - from;
642 if (state->parts[p].has_info)
643 info = &state->parts[p].info;
644 part = add_partition(disk, p, from, size,
645 state->parts[p].flags,
646 &state->parts[p].info);
648 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
649 disk->disk_name, p, -PTR_ERR(part));
652 #ifdef CONFIG_BLK_DEV_MD
653 if (state->parts[p].flags & ADDPART_FLAG_RAID)
654 md_autodetect_dev(part_to_dev(part)->devt);
661 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
663 struct address_space *mapping = bdev->bd_inode->i_mapping;
666 page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
672 return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
674 page_cache_release(page);
680 EXPORT_SYMBOL(read_dev_sector);