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authorAl Viro <viro@zeniv.linux.org.uk>2011-09-16 00:25:05 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2012-01-03 22:54:06 -0500
commit9be96f3fd10187f185d84cf878cf032465bcced3 (patch)
tree432a430ed9e0cbe0c18916cd3c3992f09b3feb37 /block/partitions/check.c
parent4752bc309b7604d507c973c7b7678ac2ce10a058 (diff)
move fs/partitions to block/
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'block/partitions/check.c')
-rw-r--r--block/partitions/check.c687
1 files changed, 687 insertions, 0 deletions
diff --git a/block/partitions/check.c b/block/partitions/check.c
new file mode 100644
index 000000000000..e3c63d1c5e13
--- /dev/null
+++ b/block/partitions/check.c
@@ -0,0 +1,687 @@
1/*
2 * fs/partitions/check.c
3 *
4 * Code extracted from drivers/block/genhd.c
5 * Copyright (C) 1991-1998 Linus Torvalds
6 * Re-organised Feb 1998 Russell King
7 *
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
11 * contained.
12 *
13 * Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
14 */
15
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/fs.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>
24
25#include "check.h"
26
27#include "acorn.h"
28#include "amiga.h"
29#include "atari.h"
30#include "ldm.h"
31#include "mac.h"
32#include "msdos.h"
33#include "osf.h"
34#include "sgi.h"
35#include "sun.h"
36#include "ibm.h"
37#include "ultrix.h"
38#include "efi.h"
39#include "karma.h"
40#include "sysv68.h"
41
42#ifdef CONFIG_BLK_DEV_MD
43extern void md_autodetect_dev(dev_t dev);
44#endif
45
46int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
47
48static int (*check_part[])(struct parsed_partitions *) = {
49 /*
50 * Probe partition formats with tables at disk address 0
51 * that also have an ADFS boot block at 0xdc0.
52 */
53#ifdef CONFIG_ACORN_PARTITION_ICS
54 adfspart_check_ICS,
55#endif
56#ifdef CONFIG_ACORN_PARTITION_POWERTEC
57 adfspart_check_POWERTEC,
58#endif
59#ifdef CONFIG_ACORN_PARTITION_EESOX
60 adfspart_check_EESOX,
61#endif
62
63 /*
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
67 * the msdos entry.
68 */
69#ifdef CONFIG_ACORN_PARTITION_CUMANA
70 adfspart_check_CUMANA,
71#endif
72#ifdef CONFIG_ACORN_PARTITION_ADFS
73 adfspart_check_ADFS,
74#endif
75
76#ifdef CONFIG_EFI_PARTITION
77 efi_partition, /* this must come before msdos */
78#endif
79#ifdef CONFIG_SGI_PARTITION
80 sgi_partition,
81#endif
82#ifdef CONFIG_LDM_PARTITION
83 ldm_partition, /* this must come before msdos */
84#endif
85#ifdef CONFIG_MSDOS_PARTITION
86 msdos_partition,
87#endif
88#ifdef CONFIG_OSF_PARTITION
89 osf_partition,
90#endif
91#ifdef CONFIG_SUN_PARTITION
92 sun_partition,
93#endif
94#ifdef CONFIG_AMIGA_PARTITION
95 amiga_partition,
96#endif
97#ifdef CONFIG_ATARI_PARTITION
98 atari_partition,
99#endif
100#ifdef CONFIG_MAC_PARTITION
101 mac_partition,
102#endif
103#ifdef CONFIG_ULTRIX_PARTITION
104 ultrix_partition,
105#endif
106#ifdef CONFIG_IBM_PARTITION
107 ibm_partition,
108#endif
109#ifdef CONFIG_KARMA_PARTITION
110 karma_partition,
111#endif
112#ifdef CONFIG_SYSV68_PARTITION
113 sysv68_partition,
114#endif
115 NULL
116};
117
118/*
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).
123 */
124
125char *disk_name(struct gendisk *hd, int partno, char *buf)
126{
127 if (!partno)
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);
131 else
132 snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
133
134 return buf;
135}
136
137const char *bdevname(struct block_device *bdev, char *buf)
138{
139 return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
140}
141
142EXPORT_SYMBOL(bdevname);
143
144/*
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.
148 */
149const char *__bdevname(dev_t dev, char *buffer)
150{
151 scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
152 MAJOR(dev), MINOR(dev));
153 return buffer;
154}
155
156EXPORT_SYMBOL(__bdevname);
157
158static struct parsed_partitions *
159check_partition(struct gendisk *hd, struct block_device *bdev)
160{
161 struct parsed_partitions *state;
162 int i, res, err;
163
164 state = kzalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
165 if (!state)
166 return NULL;
167 state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
168 if (!state->pp_buf) {
169 kfree(state);
170 return NULL;
171 }
172 state->pp_buf[0] = '\0';
173
174 state->bdev = bdev;
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");
179
180 state->limit = disk_max_parts(hd);
181 i = res = err = 0;
182 while (!res && check_part[i]) {
183 memset(&state->parts, 0, sizeof(state->parts));
184 res = check_part[i++](state);
185 if (res < 0) {
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.
188 */
189 err = res;
190 res = 0;
191 }
192
193 }
194 if (res > 0) {
195 printk(KERN_INFO "%s", state->pp_buf);
196
197 free_page((unsigned long)state->pp_buf);
198 return state;
199 }
200 if (state->access_beyond_eod)
201 err = -ENOSPC;
202 if (err)
203 /* The partition is unrecognized. So report I/O errors if there were any */
204 res = err;
205 if (!res)
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);
209
210 printk(KERN_INFO "%s", state->pp_buf);
211
212 free_page((unsigned long)state->pp_buf);
213 kfree(state);
214 return ERR_PTR(res);
215}
216
217static ssize_t part_partition_show(struct device *dev,
218 struct device_attribute *attr, char *buf)
219{
220 struct hd_struct *p = dev_to_part(dev);
221
222 return sprintf(buf, "%d\n", p->partno);
223}
224
225static ssize_t part_start_show(struct device *dev,
226 struct device_attribute *attr, char *buf)
227{
228 struct hd_struct *p = dev_to_part(dev);
229
230 return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
231}
232
233ssize_t part_size_show(struct device *dev,
234 struct device_attribute *attr, char *buf)
235{
236 struct hd_struct *p = dev_to_part(dev);
237 return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
238}
239
240static ssize_t part_ro_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
242{
243 struct hd_struct *p = dev_to_part(dev);
244 return sprintf(buf, "%d\n", p->policy ? 1 : 0);
245}
246
247static ssize_t part_alignment_offset_show(struct device *dev,
248 struct device_attribute *attr, char *buf)
249{
250 struct hd_struct *p = dev_to_part(dev);
251 return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
252}
253
254static ssize_t part_discard_alignment_show(struct device *dev,
255 struct device_attribute *attr, char *buf)
256{
257 struct hd_struct *p = dev_to_part(dev);
258 return sprintf(buf, "%u\n", p->discard_alignment);
259}
260
261ssize_t part_stat_show(struct device *dev,
262 struct device_attribute *attr, char *buf)
263{
264 struct hd_struct *p = dev_to_part(dev);
265 int cpu;
266
267 cpu = part_stat_lock();
268 part_round_stats(cpu, p);
269 part_stat_unlock();
270 return sprintf(buf,
271 "%8lu %8lu %8llu %8u "
272 "%8lu %8lu %8llu %8u "
273 "%8u %8u %8u"
274 "\n",
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])),
283 part_in_flight(p),
284 jiffies_to_msecs(part_stat_read(p, io_ticks)),
285 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
286}
287
288ssize_t part_inflight_show(struct device *dev,
289 struct device_attribute *attr, char *buf)
290{
291 struct hd_struct *p = dev_to_part(dev);
292
293 return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]),
294 atomic_read(&p->in_flight[1]));
295}
296
297#ifdef CONFIG_FAIL_MAKE_REQUEST
298ssize_t part_fail_show(struct device *dev,
299 struct device_attribute *attr, char *buf)
300{
301 struct hd_struct *p = dev_to_part(dev);
302
303 return sprintf(buf, "%d\n", p->make_it_fail);
304}
305
306ssize_t part_fail_store(struct device *dev,
307 struct device_attribute *attr,
308 const char *buf, size_t count)
309{
310 struct hd_struct *p = dev_to_part(dev);
311 int i;
312
313 if (count > 0 && sscanf(buf, "%d", &i) > 0)
314 p->make_it_fail = (i == 0) ? 0 : 1;
315
316 return count;
317}
318#endif
319
320static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
321static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
322static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
323static DEVICE_ATTR(ro, S_IRUGO, part_ro_show, NULL);
324static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
325static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
326 NULL);
327static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
328static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
329#ifdef CONFIG_FAIL_MAKE_REQUEST
330static struct device_attribute dev_attr_fail =
331 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
332#endif
333
334static struct attribute *part_attrs[] = {
335 &dev_attr_partition.attr,
336 &dev_attr_start.attr,
337 &dev_attr_size.attr,
338 &dev_attr_ro.attr,
339 &dev_attr_alignment_offset.attr,
340 &dev_attr_discard_alignment.attr,
341 &dev_attr_stat.attr,
342 &dev_attr_inflight.attr,
343#ifdef CONFIG_FAIL_MAKE_REQUEST
344 &dev_attr_fail.attr,
345#endif
346 NULL
347};
348
349static struct attribute_group part_attr_group = {
350 .attrs = part_attrs,
351};
352
353static const struct attribute_group *part_attr_groups[] = {
354 &part_attr_group,
355#ifdef CONFIG_BLK_DEV_IO_TRACE
356 &blk_trace_attr_group,
357#endif
358 NULL
359};
360
361static void part_release(struct device *dev)
362{
363 struct hd_struct *p = dev_to_part(dev);
364 free_part_stats(p);
365 free_part_info(p);
366 kfree(p);
367}
368
369struct device_type part_type = {
370 .name = "partition",
371 .groups = part_attr_groups,
372 .release = part_release,
373};
374
375static void delete_partition_rcu_cb(struct rcu_head *head)
376{
377 struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
378
379 part->start_sect = 0;
380 part->nr_sects = 0;
381 part_stat_set_all(part, 0);
382 put_device(part_to_dev(part));
383}
384
385void __delete_partition(struct hd_struct *part)
386{
387 call_rcu(&part->rcu_head, delete_partition_rcu_cb);
388}
389
390void delete_partition(struct gendisk *disk, int partno)
391{
392 struct disk_part_tbl *ptbl = disk->part_tbl;
393 struct hd_struct *part;
394
395 if (partno >= ptbl->len)
396 return;
397
398 part = ptbl->part[partno];
399 if (!part)
400 return;
401
402 blk_free_devt(part_devt(part));
403 rcu_assign_pointer(ptbl->part[partno], NULL);
404 rcu_assign_pointer(ptbl->last_lookup, NULL);
405 kobject_put(part->holder_dir);
406 device_del(part_to_dev(part));
407
408 hd_struct_put(part);
409}
410
411static ssize_t whole_disk_show(struct device *dev,
412 struct device_attribute *attr, char *buf)
413{
414 return 0;
415}
416static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
417 whole_disk_show, NULL);
418
419struct hd_struct *add_partition(struct gendisk *disk, int partno,
420 sector_t start, sector_t len, int flags,
421 struct partition_meta_info *info)
422{
423 struct hd_struct *p;
424 dev_t devt = MKDEV(0, 0);
425 struct device *ddev = disk_to_dev(disk);
426 struct device *pdev;
427 struct disk_part_tbl *ptbl;
428 const char *dname;
429 int err;
430
431 err = disk_expand_part_tbl(disk, partno);
432 if (err)
433 return ERR_PTR(err);
434 ptbl = disk->part_tbl;
435
436 if (ptbl->part[partno])
437 return ERR_PTR(-EBUSY);
438
439 p = kzalloc(sizeof(*p), GFP_KERNEL);
440 if (!p)
441 return ERR_PTR(-EBUSY);
442
443 if (!init_part_stats(p)) {
444 err = -ENOMEM;
445 goto out_free;
446 }
447 pdev = part_to_dev(p);
448
449 p->start_sect = start;
450 p->alignment_offset =
451 queue_limit_alignment_offset(&disk->queue->limits, start);
452 p->discard_alignment =
453 queue_limit_discard_alignment(&disk->queue->limits, start);
454 p->nr_sects = len;
455 p->partno = partno;
456 p->policy = get_disk_ro(disk);
457
458 if (info) {
459 struct partition_meta_info *pinfo = alloc_part_info(disk);
460 if (!pinfo)
461 goto out_free_stats;
462 memcpy(pinfo, info, sizeof(*info));
463 p->info = pinfo;
464 }
465
466 dname = dev_name(ddev);
467 if (isdigit(dname[strlen(dname) - 1]))
468 dev_set_name(pdev, "%sp%d", dname, partno);
469 else
470 dev_set_name(pdev, "%s%d", dname, partno);
471
472 device_initialize(pdev);
473 pdev->class = &block_class;
474 pdev->type = &part_type;
475 pdev->parent = ddev;
476
477 err = blk_alloc_devt(p, &devt);
478 if (err)
479 goto out_free_info;
480 pdev->devt = devt;
481
482 /* delay uevent until 'holders' subdir is created */
483 dev_set_uevent_suppress(pdev, 1);
484 err = device_add(pdev);
485 if (err)
486 goto out_put;
487
488 err = -ENOMEM;
489 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
490 if (!p->holder_dir)
491 goto out_del;
492
493 dev_set_uevent_suppress(pdev, 0);
494 if (flags & ADDPART_FLAG_WHOLEDISK) {
495 err = device_create_file(pdev, &dev_attr_whole_disk);
496 if (err)
497 goto out_del;
498 }
499
500 /* everything is up and running, commence */
501 rcu_assign_pointer(ptbl->part[partno], p);
502
503 /* suppress uevent if the disk suppresses it */
504 if (!dev_get_uevent_suppress(ddev))
505 kobject_uevent(&pdev->kobj, KOBJ_ADD);
506
507 hd_ref_init(p);
508 return p;
509
510out_free_info:
511 free_part_info(p);
512out_free_stats:
513 free_part_stats(p);
514out_free:
515 kfree(p);
516 return ERR_PTR(err);
517out_del:
518 kobject_put(p->holder_dir);
519 device_del(pdev);
520out_put:
521 put_device(pdev);
522 blk_free_devt(devt);
523 return ERR_PTR(err);
524}
525
526static bool disk_unlock_native_capacity(struct gendisk *disk)
527{
528 const struct block_device_operations *bdops = disk->fops;
529
530 if (bdops->unlock_native_capacity &&
531 !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
532 printk(KERN_CONT "enabling native capacity\n");
533 bdops->unlock_native_capacity(disk);
534 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
535 return true;
536 } else {
537 printk(KERN_CONT "truncated\n");
538 return false;
539 }
540}
541
542int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
543{
544 struct parsed_partitions *state = NULL;
545 struct disk_part_iter piter;
546 struct hd_struct *part;
547 int p, highest, res;
548rescan:
549 if (state && !IS_ERR(state)) {
550 kfree(state);
551 state = NULL;
552 }
553
554 if (bdev->bd_part_count)
555 return -EBUSY;
556 res = invalidate_partition(disk, 0);
557 if (res)
558 return res;
559
560 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
561 while ((part = disk_part_iter_next(&piter)))
562 delete_partition(disk, part->partno);
563 disk_part_iter_exit(&piter);
564
565 if (disk->fops->revalidate_disk)
566 disk->fops->revalidate_disk(disk);
567 check_disk_size_change(disk, bdev);
568 bdev->bd_invalidated = 0;
569 if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
570 return 0;
571 if (IS_ERR(state)) {
572 /*
573 * I/O error reading the partition table. If any
574 * partition code tried to read beyond EOD, retry
575 * after unlocking native capacity.
576 */
577 if (PTR_ERR(state) == -ENOSPC) {
578 printk(KERN_WARNING "%s: partition table beyond EOD, ",
579 disk->disk_name);
580 if (disk_unlock_native_capacity(disk))
581 goto rescan;
582 }
583 return -EIO;
584 }
585 /*
586 * If any partition code tried to read beyond EOD, try
587 * unlocking native capacity even if partition table is
588 * successfully read as we could be missing some partitions.
589 */
590 if (state->access_beyond_eod) {
591 printk(KERN_WARNING
592 "%s: partition table partially beyond EOD, ",
593 disk->disk_name);
594 if (disk_unlock_native_capacity(disk))
595 goto rescan;
596 }
597
598 /* tell userspace that the media / partition table may have changed */
599 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
600
601 /* Detect the highest partition number and preallocate
602 * disk->part_tbl. This is an optimization and not strictly
603 * necessary.
604 */
605 for (p = 1, highest = 0; p < state->limit; p++)
606 if (state->parts[p].size)
607 highest = p;
608
609 disk_expand_part_tbl(disk, highest);
610
611 /* add partitions */
612 for (p = 1; p < state->limit; p++) {
613 sector_t size, from;
614 struct partition_meta_info *info = NULL;
615
616 size = state->parts[p].size;
617 if (!size)
618 continue;
619
620 from = state->parts[p].from;
621 if (from >= get_capacity(disk)) {
622 printk(KERN_WARNING
623 "%s: p%d start %llu is beyond EOD, ",
624 disk->disk_name, p, (unsigned long long) from);
625 if (disk_unlock_native_capacity(disk))
626 goto rescan;
627 continue;
628 }
629
630 if (from + size > get_capacity(disk)) {
631 printk(KERN_WARNING
632 "%s: p%d size %llu extends beyond EOD, ",
633 disk->disk_name, p, (unsigned long long) size);
634
635 if (disk_unlock_native_capacity(disk)) {
636 /* free state and restart */
637 goto rescan;
638 } else {
639 /*
640 * we can not ignore partitions of broken tables
641 * created by for example camera firmware, but
642 * we limit them to the end of the disk to avoid
643 * creating invalid block devices
644 */
645 size = get_capacity(disk) - from;
646 }
647 }
648
649 if (state->parts[p].has_info)
650 info = &state->parts[p].info;
651 part = add_partition(disk, p, from, size,
652 state->parts[p].flags,
653 &state->parts[p].info);
654 if (IS_ERR(part)) {
655 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
656 disk->disk_name, p, -PTR_ERR(part));
657 continue;
658 }
659#ifdef CONFIG_BLK_DEV_MD
660 if (state->parts[p].flags & ADDPART_FLAG_RAID)
661 md_autodetect_dev(part_to_dev(part)->devt);
662#endif
663 }
664 kfree(state);
665 return 0;
666}
667
668unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
669{
670 struct address_space *mapping = bdev->bd_inode->i_mapping;
671 struct page *page;
672
673 page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
674 NULL);
675 if (!IS_ERR(page)) {
676 if (PageError(page))
677 goto fail;
678 p->v = page;
679 return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
680fail:
681 page_cache_release(page);
682 }
683 p->v = NULL;
684 return NULL;
685}
686
687EXPORT_SYMBOL(read_dev_sector);