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1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 1991-1998 Linus Torvalds
4 * Re-organised Feb 1998 Russell King
5 */
6 #include <linux/fs.h>
7 #include <linux/slab.h>
8 #include <linux/ctype.h>
9 #include <linux/genhd.h>
10 #include <linux/vmalloc.h>
11 #include <linux/blktrace_api.h>
12 #include <linux/raid/detect.h>
13 #include "check.h"
14
15 static int (*check_part[])(struct parsed_partitions *) = {
16 /*
17 * Probe partition formats with tables at disk address 0
18 * that also have an ADFS boot block at 0xdc0.
19 */
20 #ifdef CONFIG_ACORN_PARTITION_ICS
21 adfspart_check_ICS,
22 #endif
23 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
24 adfspart_check_POWERTEC,
25 #endif
26 #ifdef CONFIG_ACORN_PARTITION_EESOX
27 adfspart_check_EESOX,
28 #endif
29
30 /*
31 * Now move on to formats that only have partition info at
32 * disk address 0xdc0. Since these may also have stale
33 * PC/BIOS partition tables, they need to come before
34 * the msdos entry.
35 */
36 #ifdef CONFIG_ACORN_PARTITION_CUMANA
37 adfspart_check_CUMANA,
38 #endif
39 #ifdef CONFIG_ACORN_PARTITION_ADFS
40 adfspart_check_ADFS,
41 #endif
42
43 #ifdef CONFIG_CMDLINE_PARTITION
44 cmdline_partition,
45 #endif
46 #ifdef CONFIG_EFI_PARTITION
47 efi_partition, /* this must come before msdos */
48 #endif
49 #ifdef CONFIG_SGI_PARTITION
50 sgi_partition,
51 #endif
52 #ifdef CONFIG_LDM_PARTITION
53 ldm_partition, /* this must come before msdos */
54 #endif
55 #ifdef CONFIG_MSDOS_PARTITION
56 msdos_partition,
57 #endif
58 #ifdef CONFIG_OSF_PARTITION
59 osf_partition,
60 #endif
61 #ifdef CONFIG_SUN_PARTITION
62 sun_partition,
63 #endif
64 #ifdef CONFIG_AMIGA_PARTITION
65 amiga_partition,
66 #endif
67 #ifdef CONFIG_ATARI_PARTITION
68 atari_partition,
69 #endif
70 #ifdef CONFIG_MAC_PARTITION
71 mac_partition,
72 #endif
73 #ifdef CONFIG_ULTRIX_PARTITION
74 ultrix_partition,
75 #endif
76 #ifdef CONFIG_IBM_PARTITION
77 ibm_partition,
78 #endif
79 #ifdef CONFIG_KARMA_PARTITION
80 karma_partition,
81 #endif
82 #ifdef CONFIG_SYSV68_PARTITION
83 sysv68_partition,
84 #endif
85 NULL
86 };
87
88 static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
89 {
90 struct parsed_partitions *state;
91 int nr;
92
93 state = kzalloc(sizeof(*state), GFP_KERNEL);
94 if (!state)
95 return NULL;
96
97 nr = disk_max_parts(hd);
98 state->parts = vzalloc(array_size(nr, sizeof(state->parts[0])));
99 if (!state->parts) {
100 kfree(state);
101 return NULL;
102 }
103
104 state->limit = nr;
105
106 return state;
107 }
108
109 static void free_partitions(struct parsed_partitions *state)
110 {
111 vfree(state->parts);
112 kfree(state);
113 }
114
115 static struct parsed_partitions *check_partition(struct gendisk *hd,
116 struct block_device *bdev)
117 {
118 struct parsed_partitions *state;
119 int i, res, err;
120
121 state = allocate_partitions(hd);
122 if (!state)
123 return NULL;
124 state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
125 if (!state->pp_buf) {
126 free_partitions(state);
127 return NULL;
128 }
129 state->pp_buf[0] = '\0';
130
131 state->bdev = bdev;
132 disk_name(hd, 0, state->name);
133 snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
134 if (isdigit(state->name[strlen(state->name)-1]))
135 sprintf(state->name, "p");
136
137 i = res = err = 0;
138 while (!res && check_part[i]) {
139 memset(state->parts, 0, state->limit * sizeof(state->parts[0]));
140 res = check_part[i++](state);
141 if (res < 0) {
142 /*
143 * We have hit an I/O error which we don't report now.
144 * But record it, and let the others do their job.
145 */
146 err = res;
147 res = 0;
148 }
149
150 }
151 if (res > 0) {
152 printk(KERN_INFO "%s", state->pp_buf);
153
154 free_page((unsigned long)state->pp_buf);
155 return state;
156 }
157 if (state->access_beyond_eod)
158 err = -ENOSPC;
159 /*
160 * The partition is unrecognized. So report I/O errors if there were any
161 */
162 if (err)
163 res = err;
164 if (res) {
165 strlcat(state->pp_buf,
166 " unable to read partition table\n", PAGE_SIZE);
167 printk(KERN_INFO "%s", state->pp_buf);
168 }
169
170 free_page((unsigned long)state->pp_buf);
171 free_partitions(state);
172 return ERR_PTR(res);
173 }
174
175 static ssize_t part_partition_show(struct device *dev,
176 struct device_attribute *attr, char *buf)
177 {
178 struct hd_struct *p = dev_to_part(dev);
179
180 return sprintf(buf, "%d\n", p->partno);
181 }
182
183 static ssize_t part_start_show(struct device *dev,
184 struct device_attribute *attr, char *buf)
185 {
186 struct hd_struct *p = dev_to_part(dev);
187
188 return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
189 }
190
191 static ssize_t part_ro_show(struct device *dev,
192 struct device_attribute *attr, char *buf)
193 {
194 struct hd_struct *p = dev_to_part(dev);
195 return sprintf(buf, "%d\n", p->policy ? 1 : 0);
196 }
197
198 static ssize_t part_alignment_offset_show(struct device *dev,
199 struct device_attribute *attr, char *buf)
200 {
201 struct hd_struct *p = dev_to_part(dev);
202
203 return sprintf(buf, "%u\n",
204 queue_limit_alignment_offset(&part_to_disk(p)->queue->limits,
205 p->start_sect));
206 }
207
208 static ssize_t part_discard_alignment_show(struct device *dev,
209 struct device_attribute *attr, char *buf)
210 {
211 struct hd_struct *p = dev_to_part(dev);
212
213 return sprintf(buf, "%u\n",
214 queue_limit_discard_alignment(&part_to_disk(p)->queue->limits,
215 p->start_sect));
216 }
217
218 static DEVICE_ATTR(partition, 0444, part_partition_show, NULL);
219 static DEVICE_ATTR(start, 0444, part_start_show, NULL);
220 static DEVICE_ATTR(size, 0444, part_size_show, NULL);
221 static DEVICE_ATTR(ro, 0444, part_ro_show, NULL);
222 static DEVICE_ATTR(alignment_offset, 0444, part_alignment_offset_show, NULL);
223 static DEVICE_ATTR(discard_alignment, 0444, part_discard_alignment_show, NULL);
224 static DEVICE_ATTR(stat, 0444, part_stat_show, NULL);
225 static DEVICE_ATTR(inflight, 0444, part_inflight_show, NULL);
226 #ifdef CONFIG_FAIL_MAKE_REQUEST
227 static struct device_attribute dev_attr_fail =
228 __ATTR(make-it-fail, 0644, part_fail_show, part_fail_store);
229 #endif
230
231 static struct attribute *part_attrs[] = {
232 &dev_attr_partition.attr,
233 &dev_attr_start.attr,
234 &dev_attr_size.attr,
235 &dev_attr_ro.attr,
236 &dev_attr_alignment_offset.attr,
237 &dev_attr_discard_alignment.attr,
238 &dev_attr_stat.attr,
239 &dev_attr_inflight.attr,
240 #ifdef CONFIG_FAIL_MAKE_REQUEST
241 &dev_attr_fail.attr,
242 #endif
243 NULL
244 };
245
246 static struct attribute_group part_attr_group = {
247 .attrs = part_attrs,
248 };
249
250 static const struct attribute_group *part_attr_groups[] = {
251 &part_attr_group,
252 #ifdef CONFIG_BLK_DEV_IO_TRACE
253 &blk_trace_attr_group,
254 #endif
255 NULL
256 };
257
258 static void part_release(struct device *dev)
259 {
260 struct hd_struct *p = dev_to_part(dev);
261 blk_free_devt(dev->devt);
262 hd_free_part(p);
263 kfree(p);
264 }
265
266 static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
267 {
268 struct hd_struct *part = dev_to_part(dev);
269
270 add_uevent_var(env, "PARTN=%u", part->partno);
271 if (part->info && part->info->volname[0])
272 add_uevent_var(env, "PARTNAME=%s", part->info->volname);
273 return 0;
274 }
275
276 struct device_type part_type = {
277 .name = "partition",
278 .groups = part_attr_groups,
279 .release = part_release,
280 .uevent = part_uevent,
281 };
282
283 static void hd_struct_free_work(struct work_struct *work)
284 {
285 struct hd_struct *part =
286 container_of(to_rcu_work(work), struct hd_struct, rcu_work);
287 struct gendisk *disk = part_to_disk(part);
288
289 /*
290 * Release the disk reference acquired in delete_partition here.
291 * We can't release it in hd_struct_free because the final put_device
292 * needs process context and thus can't be run directly from a
293 * percpu_ref ->release handler.
294 */
295 put_device(disk_to_dev(disk));
296
297 part->start_sect = 0;
298 part->nr_sects = 0;
299 part_stat_set_all(part, 0);
300 put_device(part_to_dev(part));
301 }
302
303 static void hd_struct_free(struct percpu_ref *ref)
304 {
305 struct hd_struct *part = container_of(ref, struct hd_struct, ref);
306 struct gendisk *disk = part_to_disk(part);
307 struct disk_part_tbl *ptbl =
308 rcu_dereference_protected(disk->part_tbl, 1);
309
310 rcu_assign_pointer(ptbl->last_lookup, NULL);
311
312 INIT_RCU_WORK(&part->rcu_work, hd_struct_free_work);
313 queue_rcu_work(system_wq, &part->rcu_work);
314 }
315
316 int hd_ref_init(struct hd_struct *part)
317 {
318 if (percpu_ref_init(&part->ref, hd_struct_free, 0, GFP_KERNEL))
319 return -ENOMEM;
320 return 0;
321 }
322
323 /*
324 * Must be called either with bd_mutex held, before a disk can be opened or
325 * after all disk users are gone.
326 */
327 void delete_partition(struct hd_struct *part)
328 {
329 struct gendisk *disk = part_to_disk(part);
330 struct disk_part_tbl *ptbl =
331 rcu_dereference_protected(disk->part_tbl, 1);
332
333 /*
334 * ->part_tbl is referenced in this part's release handler, so
335 * we have to hold the disk device
336 */
337 get_device(disk_to_dev(disk));
338 rcu_assign_pointer(ptbl->part[part->partno], NULL);
339 kobject_put(part->holder_dir);
340 device_del(part_to_dev(part));
341
342 /*
343 * Remove the block device from the inode hash, so that it cannot be
344 * looked up any more even when openers still hold references.
345 */
346 remove_inode_hash(part->bdev->bd_inode);
347
348 percpu_ref_kill(&part->ref);
349 }
350
351 static ssize_t whole_disk_show(struct device *dev,
352 struct device_attribute *attr, char *buf)
353 {
354 return 0;
355 }
356 static DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
357
358 /*
359 * Must be called either with bd_mutex held, before a disk can be opened or
360 * after all disk users are gone.
361 */
362 static struct hd_struct *add_partition(struct gendisk *disk, int partno,
363 sector_t start, sector_t len, int flags,
364 struct partition_meta_info *info)
365 {
366 struct hd_struct *p;
367 dev_t devt = MKDEV(0, 0);
368 struct device *ddev = disk_to_dev(disk);
369 struct device *pdev;
370 struct block_device *bdev;
371 struct disk_part_tbl *ptbl;
372 const char *dname;
373 int err;
374
375 /*
376 * Partitions are not supported on zoned block devices that are used as
377 * such.
378 */
379 switch (disk->queue->limits.zoned) {
380 case BLK_ZONED_HM:
381 pr_warn("%s: partitions not supported on host managed zoned block device\n",
382 disk->disk_name);
383 return ERR_PTR(-ENXIO);
384 case BLK_ZONED_HA:
385 pr_info("%s: disabling host aware zoned block device support due to partitions\n",
386 disk->disk_name);
387 disk->queue->limits.zoned = BLK_ZONED_NONE;
388 break;
389 case BLK_ZONED_NONE:
390 break;
391 }
392
393 err = disk_expand_part_tbl(disk, partno);
394 if (err)
395 return ERR_PTR(err);
396 ptbl = rcu_dereference_protected(disk->part_tbl, 1);
397
398 if (ptbl->part[partno])
399 return ERR_PTR(-EBUSY);
400
401 p = kzalloc(sizeof(*p), GFP_KERNEL);
402 if (!p)
403 return ERR_PTR(-EBUSY);
404
405 err = -ENOMEM;
406 p->dkstats = alloc_percpu(struct disk_stats);
407 if (!p->dkstats)
408 goto out_free;
409
410 bdev = bdev_alloc(disk, partno);
411 if (!bdev)
412 goto out_free_stats;
413 p->bdev = bdev;
414
415 hd_sects_seq_init(p);
416 pdev = part_to_dev(p);
417
418 p->start_sect = start;
419 p->nr_sects = len;
420 p->partno = partno;
421 p->policy = get_disk_ro(disk);
422
423 if (info) {
424 struct partition_meta_info *pinfo;
425
426 pinfo = kzalloc_node(sizeof(*pinfo), GFP_KERNEL, disk->node_id);
427 if (!pinfo)
428 goto out_bdput;
429 memcpy(pinfo, info, sizeof(*info));
430 p->info = pinfo;
431 }
432
433 dname = dev_name(ddev);
434 if (isdigit(dname[strlen(dname) - 1]))
435 dev_set_name(pdev, "%sp%d", dname, partno);
436 else
437 dev_set_name(pdev, "%s%d", dname, partno);
438
439 device_initialize(pdev);
440 pdev->class = &block_class;
441 pdev->type = &part_type;
442 pdev->parent = ddev;
443
444 err = blk_alloc_devt(p, &devt);
445 if (err)
446 goto out_free_info;
447 pdev->devt = devt;
448
449 /* delay uevent until 'holders' subdir is created */
450 dev_set_uevent_suppress(pdev, 1);
451 err = device_add(pdev);
452 if (err)
453 goto out_put;
454
455 err = -ENOMEM;
456 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
457 if (!p->holder_dir)
458 goto out_del;
459
460 dev_set_uevent_suppress(pdev, 0);
461 if (flags & ADDPART_FLAG_WHOLEDISK) {
462 err = device_create_file(pdev, &dev_attr_whole_disk);
463 if (err)
464 goto out_del;
465 }
466
467 err = hd_ref_init(p);
468 if (err) {
469 if (flags & ADDPART_FLAG_WHOLEDISK)
470 goto out_remove_file;
471 goto out_del;
472 }
473
474 /* everything is up and running, commence */
475 bdev_add(bdev, devt);
476 rcu_assign_pointer(ptbl->part[partno], p);
477
478 /* suppress uevent if the disk suppresses it */
479 if (!dev_get_uevent_suppress(ddev))
480 kobject_uevent(&pdev->kobj, KOBJ_ADD);
481 return p;
482
483 out_free_info:
484 kfree(p->info);
485 out_bdput:
486 bdput(bdev);
487 out_free_stats:
488 free_percpu(p->dkstats);
489 out_free:
490 kfree(p);
491 return ERR_PTR(err);
492 out_remove_file:
493 device_remove_file(pdev, &dev_attr_whole_disk);
494 out_del:
495 kobject_put(p->holder_dir);
496 device_del(pdev);
497 out_put:
498 put_device(pdev);
499 return ERR_PTR(err);
500 }
501
502 static bool partition_overlaps(struct gendisk *disk, sector_t start,
503 sector_t length, int skip_partno)
504 {
505 struct disk_part_iter piter;
506 struct hd_struct *part;
507 bool overlap = false;
508
509 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
510 while ((part = disk_part_iter_next(&piter))) {
511 if (part->partno == skip_partno ||
512 start >= part->start_sect + part->nr_sects ||
513 start + length <= part->start_sect)
514 continue;
515 overlap = true;
516 break;
517 }
518
519 disk_part_iter_exit(&piter);
520 return overlap;
521 }
522
523 int bdev_add_partition(struct block_device *bdev, int partno,
524 sector_t start, sector_t length)
525 {
526 struct hd_struct *part;
527
528 mutex_lock(&bdev->bd_mutex);
529 if (partition_overlaps(bdev->bd_disk, start, length, -1)) {
530 mutex_unlock(&bdev->bd_mutex);
531 return -EBUSY;
532 }
533
534 part = add_partition(bdev->bd_disk, partno, start, length,
535 ADDPART_FLAG_NONE, NULL);
536 mutex_unlock(&bdev->bd_mutex);
537 return PTR_ERR_OR_ZERO(part);
538 }
539
540 int bdev_del_partition(struct block_device *bdev, int partno)
541 {
542 struct block_device *bdevp;
543 struct hd_struct *part = NULL;
544 int ret;
545
546 bdevp = bdget_disk(bdev->bd_disk, partno);
547 if (!bdevp)
548 return -ENXIO;
549
550 mutex_lock(&bdevp->bd_mutex);
551 mutex_lock_nested(&bdev->bd_mutex, 1);
552
553 ret = -ENXIO;
554 part = disk_get_part(bdev->bd_disk, partno);
555 if (!part)
556 goto out_unlock;
557
558 ret = -EBUSY;
559 if (bdevp->bd_openers)
560 goto out_unlock;
561
562 sync_blockdev(bdevp);
563 invalidate_bdev(bdevp);
564
565 delete_partition(part);
566 ret = 0;
567 out_unlock:
568 mutex_unlock(&bdev->bd_mutex);
569 mutex_unlock(&bdevp->bd_mutex);
570 bdput(bdevp);
571 if (part)
572 disk_put_part(part);
573 return ret;
574 }
575
576 int bdev_resize_partition(struct block_device *bdev, int partno,
577 sector_t start, sector_t length)
578 {
579 struct block_device *bdevp;
580 struct hd_struct *part;
581 int ret = 0;
582
583 part = disk_get_part(bdev->bd_disk, partno);
584 if (!part)
585 return -ENXIO;
586
587 ret = -ENOMEM;
588 bdevp = bdget_part(part);
589 if (!bdevp)
590 goto out_put_part;
591
592 mutex_lock(&bdevp->bd_mutex);
593 mutex_lock_nested(&bdev->bd_mutex, 1);
594
595 ret = -EINVAL;
596 if (start != part->start_sect)
597 goto out_unlock;
598
599 ret = -EBUSY;
600 if (partition_overlaps(bdev->bd_disk, start, length, partno))
601 goto out_unlock;
602
603 part_nr_sects_write(part, length);
604 bd_set_nr_sectors(bdevp, length);
605
606 ret = 0;
607 out_unlock:
608 mutex_unlock(&bdevp->bd_mutex);
609 mutex_unlock(&bdev->bd_mutex);
610 bdput(bdevp);
611 out_put_part:
612 disk_put_part(part);
613 return ret;
614 }
615
616 static bool disk_unlock_native_capacity(struct gendisk *disk)
617 {
618 const struct block_device_operations *bdops = disk->fops;
619
620 if (bdops->unlock_native_capacity &&
621 !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
622 printk(KERN_CONT "enabling native capacity\n");
623 bdops->unlock_native_capacity(disk);
624 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
625 return true;
626 } else {
627 printk(KERN_CONT "truncated\n");
628 return false;
629 }
630 }
631
632 int blk_drop_partitions(struct block_device *bdev)
633 {
634 struct disk_part_iter piter;
635 struct hd_struct *part;
636
637 if (bdev->bd_part_count)
638 return -EBUSY;
639
640 sync_blockdev(bdev);
641 invalidate_bdev(bdev);
642
643 disk_part_iter_init(&piter, bdev->bd_disk, DISK_PITER_INCL_EMPTY);
644 while ((part = disk_part_iter_next(&piter)))
645 delete_partition(part);
646 disk_part_iter_exit(&piter);
647
648 return 0;
649 }
650 #ifdef CONFIG_S390
651 /* for historic reasons in the DASD driver */
652 EXPORT_SYMBOL_GPL(blk_drop_partitions);
653 #endif
654
655 static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev,
656 struct parsed_partitions *state, int p)
657 {
658 sector_t size = state->parts[p].size;
659 sector_t from = state->parts[p].from;
660 struct hd_struct *part;
661
662 if (!size)
663 return true;
664
665 if (from >= get_capacity(disk)) {
666 printk(KERN_WARNING
667 "%s: p%d start %llu is beyond EOD, ",
668 disk->disk_name, p, (unsigned long long) from);
669 if (disk_unlock_native_capacity(disk))
670 return false;
671 return true;
672 }
673
674 if (from + size > get_capacity(disk)) {
675 printk(KERN_WARNING
676 "%s: p%d size %llu extends beyond EOD, ",
677 disk->disk_name, p, (unsigned long long) size);
678
679 if (disk_unlock_native_capacity(disk))
680 return false;
681
682 /*
683 * We can not ignore partitions of broken tables created by for
684 * example camera firmware, but we limit them to the end of the
685 * disk to avoid creating invalid block devices.
686 */
687 size = get_capacity(disk) - from;
688 }
689
690 part = add_partition(disk, p, from, size, state->parts[p].flags,
691 &state->parts[p].info);
692 if (IS_ERR(part) && PTR_ERR(part) != -ENXIO) {
693 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
694 disk->disk_name, p, -PTR_ERR(part));
695 return true;
696 }
697
698 if (IS_BUILTIN(CONFIG_BLK_DEV_MD) &&
699 (state->parts[p].flags & ADDPART_FLAG_RAID))
700 md_autodetect_dev(part_to_dev(part)->devt);
701
702 return true;
703 }
704
705 int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
706 {
707 struct parsed_partitions *state;
708 int ret = -EAGAIN, p, highest;
709
710 if (!disk_part_scan_enabled(disk))
711 return 0;
712
713 state = check_partition(disk, bdev);
714 if (!state)
715 return 0;
716 if (IS_ERR(state)) {
717 /*
718 * I/O error reading the partition table. If we tried to read
719 * beyond EOD, retry after unlocking the native capacity.
720 */
721 if (PTR_ERR(state) == -ENOSPC) {
722 printk(KERN_WARNING "%s: partition table beyond EOD, ",
723 disk->disk_name);
724 if (disk_unlock_native_capacity(disk))
725 return -EAGAIN;
726 }
727 return -EIO;
728 }
729
730 /*
731 * Partitions are not supported on host managed zoned block devices.
732 */
733 if (disk->queue->limits.zoned == BLK_ZONED_HM) {
734 pr_warn("%s: ignoring partition table on host managed zoned block device\n",
735 disk->disk_name);
736 ret = 0;
737 goto out_free_state;
738 }
739
740 /*
741 * If we read beyond EOD, try unlocking native capacity even if the
742 * partition table was successfully read as we could be missing some
743 * partitions.
744 */
745 if (state->access_beyond_eod) {
746 printk(KERN_WARNING
747 "%s: partition table partially beyond EOD, ",
748 disk->disk_name);
749 if (disk_unlock_native_capacity(disk))
750 goto out_free_state;
751 }
752
753 /* tell userspace that the media / partition table may have changed */
754 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
755
756 /*
757 * Detect the highest partition number and preallocate disk->part_tbl.
758 * This is an optimization and not strictly necessary.
759 */
760 for (p = 1, highest = 0; p < state->limit; p++)
761 if (state->parts[p].size)
762 highest = p;
763 disk_expand_part_tbl(disk, highest);
764
765 for (p = 1; p < state->limit; p++)
766 if (!blk_add_partition(disk, bdev, state, p))
767 goto out_free_state;
768
769 ret = 0;
770 out_free_state:
771 free_partitions(state);
772 return ret;
773 }
774
775 void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p)
776 {
777 struct address_space *mapping = state->bdev->bd_inode->i_mapping;
778 struct page *page;
779
780 if (n >= get_capacity(state->bdev->bd_disk)) {
781 state->access_beyond_eod = true;
782 return NULL;
783 }
784
785 page = read_mapping_page(mapping,
786 (pgoff_t)(n >> (PAGE_SHIFT - 9)), NULL);
787 if (IS_ERR(page))
788 goto out;
789 if (PageError(page))
790 goto out_put_page;
791
792 p->v = page;
793 return (unsigned char *)page_address(page) +
794 ((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << SECTOR_SHIFT);
795 out_put_page:
796 put_page(page);
797 out:
798 p->v = NULL;
799 return NULL;
800 }