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Merge commit 'v2.6.29-rc1' into irq/urgent
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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/kmod.h>
20 #include <linux/ctype.h>
21 #include <linux/genhd.h>
22
23 #include "check.h"
24
25 #include "acorn.h"
26 #include "amiga.h"
27 #include "atari.h"
28 #include "ldm.h"
29 #include "mac.h"
30 #include "msdos.h"
31 #include "osf.h"
32 #include "sgi.h"
33 #include "sun.h"
34 #include "ibm.h"
35 #include "ultrix.h"
36 #include "efi.h"
37 #include "karma.h"
38 #include "sysv68.h"
39
40 #ifdef CONFIG_BLK_DEV_MD
41 extern void md_autodetect_dev(dev_t dev);
42 #endif
43
44 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
45
46 static int (*check_part[])(struct parsed_partitions *, struct block_device *) = {
47 /*
48 * Probe partition formats with tables at disk address 0
49 * that also have an ADFS boot block at 0xdc0.
50 */
51 #ifdef CONFIG_ACORN_PARTITION_ICS
52 adfspart_check_ICS,
53 #endif
54 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
55 adfspart_check_POWERTEC,
56 #endif
57 #ifdef CONFIG_ACORN_PARTITION_EESOX
58 adfspart_check_EESOX,
59 #endif
60
61 /*
62 * Now move on to formats that only have partition info at
63 * disk address 0xdc0. Since these may also have stale
64 * PC/BIOS partition tables, they need to come before
65 * the msdos entry.
66 */
67 #ifdef CONFIG_ACORN_PARTITION_CUMANA
68 adfspart_check_CUMANA,
69 #endif
70 #ifdef CONFIG_ACORN_PARTITION_ADFS
71 adfspart_check_ADFS,
72 #endif
73
74 #ifdef CONFIG_EFI_PARTITION
75 efi_partition, /* this must come before msdos */
76 #endif
77 #ifdef CONFIG_SGI_PARTITION
78 sgi_partition,
79 #endif
80 #ifdef CONFIG_LDM_PARTITION
81 ldm_partition, /* this must come before msdos */
82 #endif
83 #ifdef CONFIG_MSDOS_PARTITION
84 msdos_partition,
85 #endif
86 #ifdef CONFIG_OSF_PARTITION
87 osf_partition,
88 #endif
89 #ifdef CONFIG_SUN_PARTITION
90 sun_partition,
91 #endif
92 #ifdef CONFIG_AMIGA_PARTITION
93 amiga_partition,
94 #endif
95 #ifdef CONFIG_ATARI_PARTITION
96 atari_partition,
97 #endif
98 #ifdef CONFIG_MAC_PARTITION
99 mac_partition,
100 #endif
101 #ifdef CONFIG_ULTRIX_PARTITION
102 ultrix_partition,
103 #endif
104 #ifdef CONFIG_IBM_PARTITION
105 ibm_partition,
106 #endif
107 #ifdef CONFIG_KARMA_PARTITION
108 karma_partition,
109 #endif
110 #ifdef CONFIG_SYSV68_PARTITION
111 sysv68_partition,
112 #endif
113 NULL
114 };
115
116 /*
117 * disk_name() is used by partition check code and the genhd driver.
118 * It formats the devicename of the indicated disk into
119 * the supplied buffer (of size at least 32), and returns
120 * a pointer to that same buffer (for convenience).
121 */
122
123 char *disk_name(struct gendisk *hd, int partno, char *buf)
124 {
125 if (!partno)
126 snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
127 else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
128 snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
129 else
130 snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
131
132 return buf;
133 }
134
135 const char *bdevname(struct block_device *bdev, char *buf)
136 {
137 return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
138 }
139
140 EXPORT_SYMBOL(bdevname);
141
142 /*
143 * There's very little reason to use this, you should really
144 * have a struct block_device just about everywhere and use
145 * bdevname() instead.
146 */
147 const char *__bdevname(dev_t dev, char *buffer)
148 {
149 scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
150 MAJOR(dev), MINOR(dev));
151 return buffer;
152 }
153
154 EXPORT_SYMBOL(__bdevname);
155
156 static struct parsed_partitions *
157 check_partition(struct gendisk *hd, struct block_device *bdev)
158 {
159 struct parsed_partitions *state;
160 int i, res, err;
161
162 state = kmalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
163 if (!state)
164 return NULL;
165
166 disk_name(hd, 0, state->name);
167 printk(KERN_INFO " %s:", state->name);
168 if (isdigit(state->name[strlen(state->name)-1]))
169 sprintf(state->name, "p");
170
171 state->limit = disk_max_parts(hd);
172 i = res = err = 0;
173 while (!res && check_part[i]) {
174 memset(&state->parts, 0, sizeof(state->parts));
175 res = check_part[i++](state, bdev);
176 if (res < 0) {
177 /* We have hit an I/O error which we don't report now.
178 * But record it, and let the others do their job.
179 */
180 err = res;
181 res = 0;
182 }
183
184 }
185 if (res > 0)
186 return state;
187 if (err)
188 /* The partition is unrecognized. So report I/O errors if there were any */
189 res = err;
190 if (!res)
191 printk(" unknown partition table\n");
192 else if (warn_no_part)
193 printk(" unable to read partition table\n");
194 kfree(state);
195 return ERR_PTR(res);
196 }
197
198 static ssize_t part_partition_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, "%d\n", p->partno);
204 }
205
206 static ssize_t part_start_show(struct device *dev,
207 struct device_attribute *attr, char *buf)
208 {
209 struct hd_struct *p = dev_to_part(dev);
210
211 return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
212 }
213
214 ssize_t part_size_show(struct device *dev,
215 struct device_attribute *attr, char *buf)
216 {
217 struct hd_struct *p = dev_to_part(dev);
218 return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
219 }
220
221 ssize_t part_stat_show(struct device *dev,
222 struct device_attribute *attr, char *buf)
223 {
224 struct hd_struct *p = dev_to_part(dev);
225 int cpu;
226
227 cpu = part_stat_lock();
228 part_round_stats(cpu, p);
229 part_stat_unlock();
230 return sprintf(buf,
231 "%8lu %8lu %8llu %8u "
232 "%8lu %8lu %8llu %8u "
233 "%8u %8u %8u"
234 "\n",
235 part_stat_read(p, ios[READ]),
236 part_stat_read(p, merges[READ]),
237 (unsigned long long)part_stat_read(p, sectors[READ]),
238 jiffies_to_msecs(part_stat_read(p, ticks[READ])),
239 part_stat_read(p, ios[WRITE]),
240 part_stat_read(p, merges[WRITE]),
241 (unsigned long long)part_stat_read(p, sectors[WRITE]),
242 jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
243 p->in_flight,
244 jiffies_to_msecs(part_stat_read(p, io_ticks)),
245 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
246 }
247
248 #ifdef CONFIG_FAIL_MAKE_REQUEST
249 ssize_t part_fail_show(struct device *dev,
250 struct device_attribute *attr, char *buf)
251 {
252 struct hd_struct *p = dev_to_part(dev);
253
254 return sprintf(buf, "%d\n", p->make_it_fail);
255 }
256
257 ssize_t part_fail_store(struct device *dev,
258 struct device_attribute *attr,
259 const char *buf, size_t count)
260 {
261 struct hd_struct *p = dev_to_part(dev);
262 int i;
263
264 if (count > 0 && sscanf(buf, "%d", &i) > 0)
265 p->make_it_fail = (i == 0) ? 0 : 1;
266
267 return count;
268 }
269 #endif
270
271 static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
272 static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
273 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
274 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
275 #ifdef CONFIG_FAIL_MAKE_REQUEST
276 static struct device_attribute dev_attr_fail =
277 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
278 #endif
279
280 static struct attribute *part_attrs[] = {
281 &dev_attr_partition.attr,
282 &dev_attr_start.attr,
283 &dev_attr_size.attr,
284 &dev_attr_stat.attr,
285 #ifdef CONFIG_FAIL_MAKE_REQUEST
286 &dev_attr_fail.attr,
287 #endif
288 NULL
289 };
290
291 static struct attribute_group part_attr_group = {
292 .attrs = part_attrs,
293 };
294
295 static struct attribute_group *part_attr_groups[] = {
296 &part_attr_group,
297 NULL
298 };
299
300 static void part_release(struct device *dev)
301 {
302 struct hd_struct *p = dev_to_part(dev);
303 free_part_stats(p);
304 kfree(p);
305 }
306
307 struct device_type part_type = {
308 .name = "partition",
309 .groups = part_attr_groups,
310 .release = part_release,
311 };
312
313 static void delete_partition_rcu_cb(struct rcu_head *head)
314 {
315 struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
316
317 part->start_sect = 0;
318 part->nr_sects = 0;
319 part_stat_set_all(part, 0);
320 put_device(part_to_dev(part));
321 }
322
323 void delete_partition(struct gendisk *disk, int partno)
324 {
325 struct disk_part_tbl *ptbl = disk->part_tbl;
326 struct hd_struct *part;
327
328 if (partno >= ptbl->len)
329 return;
330
331 part = ptbl->part[partno];
332 if (!part)
333 return;
334
335 blk_free_devt(part_devt(part));
336 rcu_assign_pointer(ptbl->part[partno], NULL);
337 rcu_assign_pointer(ptbl->last_lookup, NULL);
338 kobject_put(part->holder_dir);
339 device_del(part_to_dev(part));
340
341 call_rcu(&part->rcu_head, delete_partition_rcu_cb);
342 }
343
344 static ssize_t whole_disk_show(struct device *dev,
345 struct device_attribute *attr, char *buf)
346 {
347 return 0;
348 }
349 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
350 whole_disk_show, NULL);
351
352 struct hd_struct *add_partition(struct gendisk *disk, int partno,
353 sector_t start, sector_t len, int flags)
354 {
355 struct hd_struct *p;
356 dev_t devt = MKDEV(0, 0);
357 struct device *ddev = disk_to_dev(disk);
358 struct device *pdev;
359 struct disk_part_tbl *ptbl;
360 const char *dname;
361 int err;
362
363 err = disk_expand_part_tbl(disk, partno);
364 if (err)
365 return ERR_PTR(err);
366 ptbl = disk->part_tbl;
367
368 if (ptbl->part[partno])
369 return ERR_PTR(-EBUSY);
370
371 p = kzalloc(sizeof(*p), GFP_KERNEL);
372 if (!p)
373 return ERR_PTR(-EBUSY);
374
375 if (!init_part_stats(p)) {
376 err = -ENOMEM;
377 goto out_free;
378 }
379 pdev = part_to_dev(p);
380
381 p->start_sect = start;
382 p->nr_sects = len;
383 p->partno = partno;
384 p->policy = get_disk_ro(disk);
385
386 dname = dev_name(ddev);
387 if (isdigit(dname[strlen(dname) - 1]))
388 dev_set_name(pdev, "%sp%d", dname, partno);
389 else
390 dev_set_name(pdev, "%s%d", dname, partno);
391
392 device_initialize(pdev);
393 pdev->class = &block_class;
394 pdev->type = &part_type;
395 pdev->parent = ddev;
396
397 err = blk_alloc_devt(p, &devt);
398 if (err)
399 goto out_free_stats;
400 pdev->devt = devt;
401
402 /* delay uevent until 'holders' subdir is created */
403 pdev->uevent_suppress = 1;
404 err = device_add(pdev);
405 if (err)
406 goto out_put;
407
408 err = -ENOMEM;
409 p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
410 if (!p->holder_dir)
411 goto out_del;
412
413 pdev->uevent_suppress = 0;
414 if (flags & ADDPART_FLAG_WHOLEDISK) {
415 err = device_create_file(pdev, &dev_attr_whole_disk);
416 if (err)
417 goto out_del;
418 }
419
420 /* everything is up and running, commence */
421 INIT_RCU_HEAD(&p->rcu_head);
422 rcu_assign_pointer(ptbl->part[partno], p);
423
424 /* suppress uevent if the disk supresses it */
425 if (!ddev->uevent_suppress)
426 kobject_uevent(&pdev->kobj, KOBJ_ADD);
427
428 return p;
429
430 out_free_stats:
431 free_part_stats(p);
432 out_free:
433 kfree(p);
434 return ERR_PTR(err);
435 out_del:
436 kobject_put(p->holder_dir);
437 device_del(pdev);
438 out_put:
439 put_device(pdev);
440 blk_free_devt(devt);
441 return ERR_PTR(err);
442 }
443
444 /* Not exported, helper to add_disk(). */
445 void register_disk(struct gendisk *disk)
446 {
447 struct device *ddev = disk_to_dev(disk);
448 struct block_device *bdev;
449 struct disk_part_iter piter;
450 struct hd_struct *part;
451 int err;
452
453 ddev->parent = disk->driverfs_dev;
454
455 dev_set_name(ddev, disk->disk_name);
456
457 /* delay uevents, until we scanned partition table */
458 ddev->uevent_suppress = 1;
459
460 if (device_add(ddev))
461 return;
462 #ifndef CONFIG_SYSFS_DEPRECATED
463 err = sysfs_create_link(block_depr, &ddev->kobj,
464 kobject_name(&ddev->kobj));
465 if (err) {
466 device_del(ddev);
467 return;
468 }
469 #endif
470 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
471 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
472
473 /* No minors to use for partitions */
474 if (!disk_partitionable(disk))
475 goto exit;
476
477 /* No such device (e.g., media were just removed) */
478 if (!get_capacity(disk))
479 goto exit;
480
481 bdev = bdget_disk(disk, 0);
482 if (!bdev)
483 goto exit;
484
485 bdev->bd_invalidated = 1;
486 err = blkdev_get(bdev, FMODE_READ);
487 if (err < 0)
488 goto exit;
489 blkdev_put(bdev, FMODE_READ);
490
491 exit:
492 /* announce disk after possible partitions are created */
493 ddev->uevent_suppress = 0;
494 kobject_uevent(&ddev->kobj, KOBJ_ADD);
495
496 /* announce possible partitions */
497 disk_part_iter_init(&piter, disk, 0);
498 while ((part = disk_part_iter_next(&piter)))
499 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
500 disk_part_iter_exit(&piter);
501 }
502
503 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
504 {
505 struct disk_part_iter piter;
506 struct hd_struct *part;
507 struct parsed_partitions *state;
508 int p, highest, res;
509
510 if (bdev->bd_part_count)
511 return -EBUSY;
512 res = invalidate_partition(disk, 0);
513 if (res)
514 return res;
515
516 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
517 while ((part = disk_part_iter_next(&piter)))
518 delete_partition(disk, part->partno);
519 disk_part_iter_exit(&piter);
520
521 if (disk->fops->revalidate_disk)
522 disk->fops->revalidate_disk(disk);
523 check_disk_size_change(disk, bdev);
524 bdev->bd_invalidated = 0;
525 if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
526 return 0;
527 if (IS_ERR(state)) /* I/O error reading the partition table */
528 return -EIO;
529
530 /* tell userspace that the media / partition table may have changed */
531 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
532
533 /* Detect the highest partition number and preallocate
534 * disk->part_tbl. This is an optimization and not strictly
535 * necessary.
536 */
537 for (p = 1, highest = 0; p < state->limit; p++)
538 if (state->parts[p].size)
539 highest = p;
540
541 disk_expand_part_tbl(disk, highest);
542
543 /* add partitions */
544 for (p = 1; p < state->limit; p++) {
545 sector_t size = state->parts[p].size;
546 sector_t from = state->parts[p].from;
547 if (!size)
548 continue;
549 if (from >= get_capacity(disk)) {
550 printk(KERN_WARNING
551 "%s: p%d ignored, start %llu is behind the end of the disk\n",
552 disk->disk_name, p, (unsigned long long) from);
553 continue;
554 }
555 if (from + size > get_capacity(disk)) {
556 /*
557 * we can not ignore partitions of broken tables
558 * created by for example camera firmware, but we
559 * limit them to the end of the disk to avoid
560 * creating invalid block devices
561 */
562 printk(KERN_WARNING
563 "%s: p%d size %llu limited to end of disk\n",
564 disk->disk_name, p, (unsigned long long) size);
565 size = get_capacity(disk) - from;
566 }
567 part = add_partition(disk, p, from, size,
568 state->parts[p].flags);
569 if (IS_ERR(part)) {
570 printk(KERN_ERR " %s: p%d could not be added: %ld\n",
571 disk->disk_name, p, -PTR_ERR(part));
572 continue;
573 }
574 #ifdef CONFIG_BLK_DEV_MD
575 if (state->parts[p].flags & ADDPART_FLAG_RAID)
576 md_autodetect_dev(part_to_dev(part)->devt);
577 #endif
578 }
579 kfree(state);
580 return 0;
581 }
582
583 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
584 {
585 struct address_space *mapping = bdev->bd_inode->i_mapping;
586 struct page *page;
587
588 page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
589 NULL);
590 if (!IS_ERR(page)) {
591 if (PageError(page))
592 goto fail;
593 p->v = page;
594 return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
595 fail:
596 page_cache_release(page);
597 }
598 p->v = NULL;
599 return NULL;
600 }
601
602 EXPORT_SYMBOL(read_dev_sector);
603
604 void del_gendisk(struct gendisk *disk)
605 {
606 struct disk_part_iter piter;
607 struct hd_struct *part;
608
609 /* invalidate stuff */
610 disk_part_iter_init(&piter, disk,
611 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
612 while ((part = disk_part_iter_next(&piter))) {
613 invalidate_partition(disk, part->partno);
614 delete_partition(disk, part->partno);
615 }
616 disk_part_iter_exit(&piter);
617
618 invalidate_partition(disk, 0);
619 blk_free_devt(disk_to_dev(disk)->devt);
620 set_capacity(disk, 0);
621 disk->flags &= ~GENHD_FL_UP;
622 unlink_gendisk(disk);
623 part_stat_set_all(&disk->part0, 0);
624 disk->part0.stamp = 0;
625
626 kobject_put(disk->part0.holder_dir);
627 kobject_put(disk->slave_dir);
628 disk->driverfs_dev = NULL;
629 #ifndef CONFIG_SYSFS_DEPRECATED
630 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
631 #endif
632 device_del(disk_to_dev(disk));
633 }