xref: /linux/drivers/md/md.c (revision d67b569f5f620c0fb95d5212642746b7ba9d29e4)
1 /*
2    md.c : Multiple Devices driver for Linux
3 	  Copyright (C) 1998, 1999, 2000 Ingo Molnar
4 
5      completely rewritten, based on the MD driver code from Marc Zyngier
6 
7    Changes:
8 
9    - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
10    - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
11    - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
12    - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
13    - kmod support by: Cyrus Durgin
14    - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
15    - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
16 
17    - lots of fixes and improvements to the RAID1/RAID5 and generic
18      RAID code (such as request based resynchronization):
19 
20      Neil Brown <neilb@cse.unsw.edu.au>.
21 
22    - persistent bitmap code
23      Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
24 
25    This program is free software; you can redistribute it and/or modify
26    it under the terms of the GNU General Public License as published by
27    the Free Software Foundation; either version 2, or (at your option)
28    any later version.
29 
30    You should have received a copy of the GNU General Public License
31    (for example /usr/src/linux/COPYING); if not, write to the Free
32    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
33 */
34 
35 #include <linux/module.h>
36 #include <linux/config.h>
37 #include <linux/linkage.h>
38 #include <linux/raid/md.h>
39 #include <linux/raid/bitmap.h>
40 #include <linux/sysctl.h>
41 #include <linux/devfs_fs_kernel.h>
42 #include <linux/buffer_head.h> /* for invalidate_bdev */
43 #include <linux/suspend.h>
44 
45 #include <linux/init.h>
46 
47 #include <linux/file.h>
48 
49 #ifdef CONFIG_KMOD
50 #include <linux/kmod.h>
51 #endif
52 
53 #include <asm/unaligned.h>
54 
55 #define MAJOR_NR MD_MAJOR
56 #define MD_DRIVER
57 
58 /* 63 partitions with the alternate major number (mdp) */
59 #define MdpMinorShift 6
60 
61 #define DEBUG 0
62 #define dprintk(x...) ((void)(DEBUG && printk(x)))
63 
64 
65 #ifndef MODULE
66 static void autostart_arrays (int part);
67 #endif
68 
69 static mdk_personality_t *pers[MAX_PERSONALITY];
70 static DEFINE_SPINLOCK(pers_lock);
71 
72 /*
73  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
74  * is 1000 KB/sec, so the extra system load does not show up that much.
75  * Increase it if you want to have more _guaranteed_ speed. Note that
76  * the RAID driver will use the maximum available bandwith if the IO
77  * subsystem is idle. There is also an 'absolute maximum' reconstruction
78  * speed limit - in case reconstruction slows down your system despite
79  * idle IO detection.
80  *
81  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
82  */
83 
84 static int sysctl_speed_limit_min = 1000;
85 static int sysctl_speed_limit_max = 200000;
86 
87 static struct ctl_table_header *raid_table_header;
88 
89 static ctl_table raid_table[] = {
90 	{
91 		.ctl_name	= DEV_RAID_SPEED_LIMIT_MIN,
92 		.procname	= "speed_limit_min",
93 		.data		= &sysctl_speed_limit_min,
94 		.maxlen		= sizeof(int),
95 		.mode		= 0644,
96 		.proc_handler	= &proc_dointvec,
97 	},
98 	{
99 		.ctl_name	= DEV_RAID_SPEED_LIMIT_MAX,
100 		.procname	= "speed_limit_max",
101 		.data		= &sysctl_speed_limit_max,
102 		.maxlen		= sizeof(int),
103 		.mode		= 0644,
104 		.proc_handler	= &proc_dointvec,
105 	},
106 	{ .ctl_name = 0 }
107 };
108 
109 static ctl_table raid_dir_table[] = {
110 	{
111 		.ctl_name	= DEV_RAID,
112 		.procname	= "raid",
113 		.maxlen		= 0,
114 		.mode		= 0555,
115 		.child		= raid_table,
116 	},
117 	{ .ctl_name = 0 }
118 };
119 
120 static ctl_table raid_root_table[] = {
121 	{
122 		.ctl_name	= CTL_DEV,
123 		.procname	= "dev",
124 		.maxlen		= 0,
125 		.mode		= 0555,
126 		.child		= raid_dir_table,
127 	},
128 	{ .ctl_name = 0 }
129 };
130 
131 static struct block_device_operations md_fops;
132 
133 /*
134  * Enables to iterate over all existing md arrays
135  * all_mddevs_lock protects this list.
136  */
137 static LIST_HEAD(all_mddevs);
138 static DEFINE_SPINLOCK(all_mddevs_lock);
139 
140 
141 /*
142  * iterates through all used mddevs in the system.
143  * We take care to grab the all_mddevs_lock whenever navigating
144  * the list, and to always hold a refcount when unlocked.
145  * Any code which breaks out of this loop while own
146  * a reference to the current mddev and must mddev_put it.
147  */
148 #define ITERATE_MDDEV(mddev,tmp)					\
149 									\
150 	for (({ spin_lock(&all_mddevs_lock); 				\
151 		tmp = all_mddevs.next;					\
152 		mddev = NULL;});					\
153 	     ({ if (tmp != &all_mddevs)					\
154 			mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
155 		spin_unlock(&all_mddevs_lock);				\
156 		if (mddev) mddev_put(mddev);				\
157 		mddev = list_entry(tmp, mddev_t, all_mddevs);		\
158 		tmp != &all_mddevs;});					\
159 	     ({ spin_lock(&all_mddevs_lock);				\
160 		tmp = tmp->next;})					\
161 		)
162 
163 
164 static int md_fail_request (request_queue_t *q, struct bio *bio)
165 {
166 	bio_io_error(bio, bio->bi_size);
167 	return 0;
168 }
169 
170 static inline mddev_t *mddev_get(mddev_t *mddev)
171 {
172 	atomic_inc(&mddev->active);
173 	return mddev;
174 }
175 
176 static void mddev_put(mddev_t *mddev)
177 {
178 	if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
179 		return;
180 	if (!mddev->raid_disks && list_empty(&mddev->disks)) {
181 		list_del(&mddev->all_mddevs);
182 		blk_put_queue(mddev->queue);
183 		kfree(mddev);
184 	}
185 	spin_unlock(&all_mddevs_lock);
186 }
187 
188 static mddev_t * mddev_find(dev_t unit)
189 {
190 	mddev_t *mddev, *new = NULL;
191 
192  retry:
193 	spin_lock(&all_mddevs_lock);
194 	list_for_each_entry(mddev, &all_mddevs, all_mddevs)
195 		if (mddev->unit == unit) {
196 			mddev_get(mddev);
197 			spin_unlock(&all_mddevs_lock);
198 			kfree(new);
199 			return mddev;
200 		}
201 
202 	if (new) {
203 		list_add(&new->all_mddevs, &all_mddevs);
204 		spin_unlock(&all_mddevs_lock);
205 		return new;
206 	}
207 	spin_unlock(&all_mddevs_lock);
208 
209 	new = (mddev_t *) kmalloc(sizeof(*new), GFP_KERNEL);
210 	if (!new)
211 		return NULL;
212 
213 	memset(new, 0, sizeof(*new));
214 
215 	new->unit = unit;
216 	if (MAJOR(unit) == MD_MAJOR)
217 		new->md_minor = MINOR(unit);
218 	else
219 		new->md_minor = MINOR(unit) >> MdpMinorShift;
220 
221 	init_MUTEX(&new->reconfig_sem);
222 	INIT_LIST_HEAD(&new->disks);
223 	INIT_LIST_HEAD(&new->all_mddevs);
224 	init_timer(&new->safemode_timer);
225 	atomic_set(&new->active, 1);
226 	spin_lock_init(&new->write_lock);
227 	init_waitqueue_head(&new->sb_wait);
228 
229 	new->queue = blk_alloc_queue(GFP_KERNEL);
230 	if (!new->queue) {
231 		kfree(new);
232 		return NULL;
233 	}
234 
235 	blk_queue_make_request(new->queue, md_fail_request);
236 
237 	goto retry;
238 }
239 
240 static inline int mddev_lock(mddev_t * mddev)
241 {
242 	return down_interruptible(&mddev->reconfig_sem);
243 }
244 
245 static inline void mddev_lock_uninterruptible(mddev_t * mddev)
246 {
247 	down(&mddev->reconfig_sem);
248 }
249 
250 static inline int mddev_trylock(mddev_t * mddev)
251 {
252 	return down_trylock(&mddev->reconfig_sem);
253 }
254 
255 static inline void mddev_unlock(mddev_t * mddev)
256 {
257 	up(&mddev->reconfig_sem);
258 
259 	if (mddev->thread)
260 		md_wakeup_thread(mddev->thread);
261 }
262 
263 mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
264 {
265 	mdk_rdev_t * rdev;
266 	struct list_head *tmp;
267 
268 	ITERATE_RDEV(mddev,rdev,tmp) {
269 		if (rdev->desc_nr == nr)
270 			return rdev;
271 	}
272 	return NULL;
273 }
274 
275 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
276 {
277 	struct list_head *tmp;
278 	mdk_rdev_t *rdev;
279 
280 	ITERATE_RDEV(mddev,rdev,tmp) {
281 		if (rdev->bdev->bd_dev == dev)
282 			return rdev;
283 	}
284 	return NULL;
285 }
286 
287 inline static sector_t calc_dev_sboffset(struct block_device *bdev)
288 {
289 	sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
290 	return MD_NEW_SIZE_BLOCKS(size);
291 }
292 
293 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
294 {
295 	sector_t size;
296 
297 	size = rdev->sb_offset;
298 
299 	if (chunk_size)
300 		size &= ~((sector_t)chunk_size/1024 - 1);
301 	return size;
302 }
303 
304 static int alloc_disk_sb(mdk_rdev_t * rdev)
305 {
306 	if (rdev->sb_page)
307 		MD_BUG();
308 
309 	rdev->sb_page = alloc_page(GFP_KERNEL);
310 	if (!rdev->sb_page) {
311 		printk(KERN_ALERT "md: out of memory.\n");
312 		return -EINVAL;
313 	}
314 
315 	return 0;
316 }
317 
318 static void free_disk_sb(mdk_rdev_t * rdev)
319 {
320 	if (rdev->sb_page) {
321 		page_cache_release(rdev->sb_page);
322 		rdev->sb_loaded = 0;
323 		rdev->sb_page = NULL;
324 		rdev->sb_offset = 0;
325 		rdev->size = 0;
326 	}
327 }
328 
329 
330 static int super_written(struct bio *bio, unsigned int bytes_done, int error)
331 {
332 	mdk_rdev_t *rdev = bio->bi_private;
333 	if (bio->bi_size)
334 		return 1;
335 
336 	if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
337 		md_error(rdev->mddev, rdev);
338 
339 	if (atomic_dec_and_test(&rdev->mddev->pending_writes))
340 		wake_up(&rdev->mddev->sb_wait);
341 	bio_put(bio);
342 	return 0;
343 }
344 
345 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
346 		   sector_t sector, int size, struct page *page)
347 {
348 	/* write first size bytes of page to sector of rdev
349 	 * Increment mddev->pending_writes before returning
350 	 * and decrement it on completion, waking up sb_wait
351 	 * if zero is reached.
352 	 * If an error occurred, call md_error
353 	 */
354 	struct bio *bio = bio_alloc(GFP_NOIO, 1);
355 
356 	bio->bi_bdev = rdev->bdev;
357 	bio->bi_sector = sector;
358 	bio_add_page(bio, page, size, 0);
359 	bio->bi_private = rdev;
360 	bio->bi_end_io = super_written;
361 	atomic_inc(&mddev->pending_writes);
362 	submit_bio((1<<BIO_RW)|(1<<BIO_RW_SYNC), bio);
363 }
364 
365 static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
366 {
367 	if (bio->bi_size)
368 		return 1;
369 
370 	complete((struct completion*)bio->bi_private);
371 	return 0;
372 }
373 
374 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
375 		   struct page *page, int rw)
376 {
377 	struct bio *bio = bio_alloc(GFP_NOIO, 1);
378 	struct completion event;
379 	int ret;
380 
381 	rw |= (1 << BIO_RW_SYNC);
382 
383 	bio->bi_bdev = bdev;
384 	bio->bi_sector = sector;
385 	bio_add_page(bio, page, size, 0);
386 	init_completion(&event);
387 	bio->bi_private = &event;
388 	bio->bi_end_io = bi_complete;
389 	submit_bio(rw, bio);
390 	wait_for_completion(&event);
391 
392 	ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
393 	bio_put(bio);
394 	return ret;
395 }
396 
397 static int read_disk_sb(mdk_rdev_t * rdev)
398 {
399 	char b[BDEVNAME_SIZE];
400 	if (!rdev->sb_page) {
401 		MD_BUG();
402 		return -EINVAL;
403 	}
404 	if (rdev->sb_loaded)
405 		return 0;
406 
407 
408 	if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, READ))
409 		goto fail;
410 	rdev->sb_loaded = 1;
411 	return 0;
412 
413 fail:
414 	printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
415 		bdevname(rdev->bdev,b));
416 	return -EINVAL;
417 }
418 
419 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
420 {
421 	if (	(sb1->set_uuid0 == sb2->set_uuid0) &&
422 		(sb1->set_uuid1 == sb2->set_uuid1) &&
423 		(sb1->set_uuid2 == sb2->set_uuid2) &&
424 		(sb1->set_uuid3 == sb2->set_uuid3))
425 
426 		return 1;
427 
428 	return 0;
429 }
430 
431 
432 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
433 {
434 	int ret;
435 	mdp_super_t *tmp1, *tmp2;
436 
437 	tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
438 	tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
439 
440 	if (!tmp1 || !tmp2) {
441 		ret = 0;
442 		printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
443 		goto abort;
444 	}
445 
446 	*tmp1 = *sb1;
447 	*tmp2 = *sb2;
448 
449 	/*
450 	 * nr_disks is not constant
451 	 */
452 	tmp1->nr_disks = 0;
453 	tmp2->nr_disks = 0;
454 
455 	if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
456 		ret = 0;
457 	else
458 		ret = 1;
459 
460 abort:
461 	kfree(tmp1);
462 	kfree(tmp2);
463 	return ret;
464 }
465 
466 static unsigned int calc_sb_csum(mdp_super_t * sb)
467 {
468 	unsigned int disk_csum, csum;
469 
470 	disk_csum = sb->sb_csum;
471 	sb->sb_csum = 0;
472 	csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
473 	sb->sb_csum = disk_csum;
474 	return csum;
475 }
476 
477 
478 /*
479  * Handle superblock details.
480  * We want to be able to handle multiple superblock formats
481  * so we have a common interface to them all, and an array of
482  * different handlers.
483  * We rely on user-space to write the initial superblock, and support
484  * reading and updating of superblocks.
485  * Interface methods are:
486  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
487  *      loads and validates a superblock on dev.
488  *      if refdev != NULL, compare superblocks on both devices
489  *    Return:
490  *      0 - dev has a superblock that is compatible with refdev
491  *      1 - dev has a superblock that is compatible and newer than refdev
492  *          so dev should be used as the refdev in future
493  *     -EINVAL superblock incompatible or invalid
494  *     -othererror e.g. -EIO
495  *
496  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
497  *      Verify that dev is acceptable into mddev.
498  *       The first time, mddev->raid_disks will be 0, and data from
499  *       dev should be merged in.  Subsequent calls check that dev
500  *       is new enough.  Return 0 or -EINVAL
501  *
502  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
503  *     Update the superblock for rdev with data in mddev
504  *     This does not write to disc.
505  *
506  */
507 
508 struct super_type  {
509 	char 		*name;
510 	struct module	*owner;
511 	int		(*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
512 	int		(*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
513 	void		(*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
514 };
515 
516 /*
517  * load_super for 0.90.0
518  */
519 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
520 {
521 	char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
522 	mdp_super_t *sb;
523 	int ret;
524 	sector_t sb_offset;
525 
526 	/*
527 	 * Calculate the position of the superblock,
528 	 * it's at the end of the disk.
529 	 *
530 	 * It also happens to be a multiple of 4Kb.
531 	 */
532 	sb_offset = calc_dev_sboffset(rdev->bdev);
533 	rdev->sb_offset = sb_offset;
534 
535 	ret = read_disk_sb(rdev);
536 	if (ret) return ret;
537 
538 	ret = -EINVAL;
539 
540 	bdevname(rdev->bdev, b);
541 	sb = (mdp_super_t*)page_address(rdev->sb_page);
542 
543 	if (sb->md_magic != MD_SB_MAGIC) {
544 		printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
545 		       b);
546 		goto abort;
547 	}
548 
549 	if (sb->major_version != 0 ||
550 	    sb->minor_version != 90) {
551 		printk(KERN_WARNING "Bad version number %d.%d on %s\n",
552 			sb->major_version, sb->minor_version,
553 			b);
554 		goto abort;
555 	}
556 
557 	if (sb->raid_disks <= 0)
558 		goto abort;
559 
560 	if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
561 		printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
562 			b);
563 		goto abort;
564 	}
565 
566 	rdev->preferred_minor = sb->md_minor;
567 	rdev->data_offset = 0;
568 
569 	if (sb->level == LEVEL_MULTIPATH)
570 		rdev->desc_nr = -1;
571 	else
572 		rdev->desc_nr = sb->this_disk.number;
573 
574 	if (refdev == 0)
575 		ret = 1;
576 	else {
577 		__u64 ev1, ev2;
578 		mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
579 		if (!uuid_equal(refsb, sb)) {
580 			printk(KERN_WARNING "md: %s has different UUID to %s\n",
581 				b, bdevname(refdev->bdev,b2));
582 			goto abort;
583 		}
584 		if (!sb_equal(refsb, sb)) {
585 			printk(KERN_WARNING "md: %s has same UUID"
586 			       " but different superblock to %s\n",
587 			       b, bdevname(refdev->bdev, b2));
588 			goto abort;
589 		}
590 		ev1 = md_event(sb);
591 		ev2 = md_event(refsb);
592 		if (ev1 > ev2)
593 			ret = 1;
594 		else
595 			ret = 0;
596 	}
597 	rdev->size = calc_dev_size(rdev, sb->chunk_size);
598 
599  abort:
600 	return ret;
601 }
602 
603 /*
604  * validate_super for 0.90.0
605  */
606 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
607 {
608 	mdp_disk_t *desc;
609 	mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
610 
611 	rdev->raid_disk = -1;
612 	rdev->in_sync = 0;
613 	if (mddev->raid_disks == 0) {
614 		mddev->major_version = 0;
615 		mddev->minor_version = sb->minor_version;
616 		mddev->patch_version = sb->patch_version;
617 		mddev->persistent = ! sb->not_persistent;
618 		mddev->chunk_size = sb->chunk_size;
619 		mddev->ctime = sb->ctime;
620 		mddev->utime = sb->utime;
621 		mddev->level = sb->level;
622 		mddev->layout = sb->layout;
623 		mddev->raid_disks = sb->raid_disks;
624 		mddev->size = sb->size;
625 		mddev->events = md_event(sb);
626 
627 		if (sb->state & (1<<MD_SB_CLEAN))
628 			mddev->recovery_cp = MaxSector;
629 		else {
630 			if (sb->events_hi == sb->cp_events_hi &&
631 				sb->events_lo == sb->cp_events_lo) {
632 				mddev->recovery_cp = sb->recovery_cp;
633 			} else
634 				mddev->recovery_cp = 0;
635 		}
636 
637 		memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
638 		memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
639 		memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
640 		memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
641 
642 		mddev->max_disks = MD_SB_DISKS;
643 
644 		if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
645 		    mddev->bitmap_file == NULL) {
646 			if (mddev->level != 1) {
647 				/* FIXME use a better test */
648 				printk(KERN_WARNING "md: bitmaps only support for raid1\n");
649 				return -EINVAL;
650 			}
651 			mddev->bitmap_offset = (MD_SB_BYTES >> 9);
652 		}
653 
654 	} else if (mddev->pers == NULL) {
655 		/* Insist on good event counter while assembling */
656 		__u64 ev1 = md_event(sb);
657 		++ev1;
658 		if (ev1 < mddev->events)
659 			return -EINVAL;
660 	} else if (mddev->bitmap) {
661 		/* if adding to array with a bitmap, then we can accept an
662 		 * older device ... but not too old.
663 		 */
664 		__u64 ev1 = md_event(sb);
665 		if (ev1 < mddev->bitmap->events_cleared)
666 			return 0;
667 	} else /* just a hot-add of a new device, leave raid_disk at -1 */
668 		return 0;
669 
670 	if (mddev->level != LEVEL_MULTIPATH) {
671 		rdev->faulty = 0;
672 		desc = sb->disks + rdev->desc_nr;
673 
674 		if (desc->state & (1<<MD_DISK_FAULTY))
675 			rdev->faulty = 1;
676 		else if (desc->state & (1<<MD_DISK_SYNC) &&
677 			 desc->raid_disk < mddev->raid_disks) {
678 			rdev->in_sync = 1;
679 			rdev->raid_disk = desc->raid_disk;
680 		}
681 	} else /* MULTIPATH are always insync */
682 		rdev->in_sync = 1;
683 	return 0;
684 }
685 
686 /*
687  * sync_super for 0.90.0
688  */
689 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
690 {
691 	mdp_super_t *sb;
692 	struct list_head *tmp;
693 	mdk_rdev_t *rdev2;
694 	int next_spare = mddev->raid_disks;
695 
696 	/* make rdev->sb match mddev data..
697 	 *
698 	 * 1/ zero out disks
699 	 * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
700 	 * 3/ any empty disks < next_spare become removed
701 	 *
702 	 * disks[0] gets initialised to REMOVED because
703 	 * we cannot be sure from other fields if it has
704 	 * been initialised or not.
705 	 */
706 	int i;
707 	int active=0, working=0,failed=0,spare=0,nr_disks=0;
708 
709 	sb = (mdp_super_t*)page_address(rdev->sb_page);
710 
711 	memset(sb, 0, sizeof(*sb));
712 
713 	sb->md_magic = MD_SB_MAGIC;
714 	sb->major_version = mddev->major_version;
715 	sb->minor_version = mddev->minor_version;
716 	sb->patch_version = mddev->patch_version;
717 	sb->gvalid_words  = 0; /* ignored */
718 	memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
719 	memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
720 	memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
721 	memcpy(&sb->set_uuid3, mddev->uuid+12,4);
722 
723 	sb->ctime = mddev->ctime;
724 	sb->level = mddev->level;
725 	sb->size  = mddev->size;
726 	sb->raid_disks = mddev->raid_disks;
727 	sb->md_minor = mddev->md_minor;
728 	sb->not_persistent = !mddev->persistent;
729 	sb->utime = mddev->utime;
730 	sb->state = 0;
731 	sb->events_hi = (mddev->events>>32);
732 	sb->events_lo = (u32)mddev->events;
733 
734 	if (mddev->in_sync)
735 	{
736 		sb->recovery_cp = mddev->recovery_cp;
737 		sb->cp_events_hi = (mddev->events>>32);
738 		sb->cp_events_lo = (u32)mddev->events;
739 		if (mddev->recovery_cp == MaxSector)
740 			sb->state = (1<< MD_SB_CLEAN);
741 	} else
742 		sb->recovery_cp = 0;
743 
744 	sb->layout = mddev->layout;
745 	sb->chunk_size = mddev->chunk_size;
746 
747 	if (mddev->bitmap && mddev->bitmap_file == NULL)
748 		sb->state |= (1<<MD_SB_BITMAP_PRESENT);
749 
750 	sb->disks[0].state = (1<<MD_DISK_REMOVED);
751 	ITERATE_RDEV(mddev,rdev2,tmp) {
752 		mdp_disk_t *d;
753 		if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
754 			rdev2->desc_nr = rdev2->raid_disk;
755 		else
756 			rdev2->desc_nr = next_spare++;
757 		d = &sb->disks[rdev2->desc_nr];
758 		nr_disks++;
759 		d->number = rdev2->desc_nr;
760 		d->major = MAJOR(rdev2->bdev->bd_dev);
761 		d->minor = MINOR(rdev2->bdev->bd_dev);
762 		if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
763 			d->raid_disk = rdev2->raid_disk;
764 		else
765 			d->raid_disk = rdev2->desc_nr; /* compatibility */
766 		if (rdev2->faulty) {
767 			d->state = (1<<MD_DISK_FAULTY);
768 			failed++;
769 		} else if (rdev2->in_sync) {
770 			d->state = (1<<MD_DISK_ACTIVE);
771 			d->state |= (1<<MD_DISK_SYNC);
772 			active++;
773 			working++;
774 		} else {
775 			d->state = 0;
776 			spare++;
777 			working++;
778 		}
779 	}
780 
781 	/* now set the "removed" and "faulty" bits on any missing devices */
782 	for (i=0 ; i < mddev->raid_disks ; i++) {
783 		mdp_disk_t *d = &sb->disks[i];
784 		if (d->state == 0 && d->number == 0) {
785 			d->number = i;
786 			d->raid_disk = i;
787 			d->state = (1<<MD_DISK_REMOVED);
788 			d->state |= (1<<MD_DISK_FAULTY);
789 			failed++;
790 		}
791 	}
792 	sb->nr_disks = nr_disks;
793 	sb->active_disks = active;
794 	sb->working_disks = working;
795 	sb->failed_disks = failed;
796 	sb->spare_disks = spare;
797 
798 	sb->this_disk = sb->disks[rdev->desc_nr];
799 	sb->sb_csum = calc_sb_csum(sb);
800 }
801 
802 /*
803  * version 1 superblock
804  */
805 
806 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
807 {
808 	unsigned int disk_csum, csum;
809 	unsigned long long newcsum;
810 	int size = 256 + le32_to_cpu(sb->max_dev)*2;
811 	unsigned int *isuper = (unsigned int*)sb;
812 	int i;
813 
814 	disk_csum = sb->sb_csum;
815 	sb->sb_csum = 0;
816 	newcsum = 0;
817 	for (i=0; size>=4; size -= 4 )
818 		newcsum += le32_to_cpu(*isuper++);
819 
820 	if (size == 2)
821 		newcsum += le16_to_cpu(*(unsigned short*) isuper);
822 
823 	csum = (newcsum & 0xffffffff) + (newcsum >> 32);
824 	sb->sb_csum = disk_csum;
825 	return cpu_to_le32(csum);
826 }
827 
828 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
829 {
830 	struct mdp_superblock_1 *sb;
831 	int ret;
832 	sector_t sb_offset;
833 	char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
834 
835 	/*
836 	 * Calculate the position of the superblock.
837 	 * It is always aligned to a 4K boundary and
838 	 * depeding on minor_version, it can be:
839 	 * 0: At least 8K, but less than 12K, from end of device
840 	 * 1: At start of device
841 	 * 2: 4K from start of device.
842 	 */
843 	switch(minor_version) {
844 	case 0:
845 		sb_offset = rdev->bdev->bd_inode->i_size >> 9;
846 		sb_offset -= 8*2;
847 		sb_offset &= ~(sector_t)(4*2-1);
848 		/* convert from sectors to K */
849 		sb_offset /= 2;
850 		break;
851 	case 1:
852 		sb_offset = 0;
853 		break;
854 	case 2:
855 		sb_offset = 4;
856 		break;
857 	default:
858 		return -EINVAL;
859 	}
860 	rdev->sb_offset = sb_offset;
861 
862 	ret = read_disk_sb(rdev);
863 	if (ret) return ret;
864 
865 
866 	sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
867 
868 	if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
869 	    sb->major_version != cpu_to_le32(1) ||
870 	    le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
871 	    le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
872 	    sb->feature_map != 0)
873 		return -EINVAL;
874 
875 	if (calc_sb_1_csum(sb) != sb->sb_csum) {
876 		printk("md: invalid superblock checksum on %s\n",
877 			bdevname(rdev->bdev,b));
878 		return -EINVAL;
879 	}
880 	if (le64_to_cpu(sb->data_size) < 10) {
881 		printk("md: data_size too small on %s\n",
882 		       bdevname(rdev->bdev,b));
883 		return -EINVAL;
884 	}
885 	rdev->preferred_minor = 0xffff;
886 	rdev->data_offset = le64_to_cpu(sb->data_offset);
887 
888 	if (refdev == 0)
889 		return 1;
890 	else {
891 		__u64 ev1, ev2;
892 		struct mdp_superblock_1 *refsb =
893 			(struct mdp_superblock_1*)page_address(refdev->sb_page);
894 
895 		if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
896 		    sb->level != refsb->level ||
897 		    sb->layout != refsb->layout ||
898 		    sb->chunksize != refsb->chunksize) {
899 			printk(KERN_WARNING "md: %s has strangely different"
900 				" superblock to %s\n",
901 				bdevname(rdev->bdev,b),
902 				bdevname(refdev->bdev,b2));
903 			return -EINVAL;
904 		}
905 		ev1 = le64_to_cpu(sb->events);
906 		ev2 = le64_to_cpu(refsb->events);
907 
908 		if (ev1 > ev2)
909 			return 1;
910 	}
911 	if (minor_version)
912 		rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
913 	else
914 		rdev->size = rdev->sb_offset;
915 	if (rdev->size < le64_to_cpu(sb->data_size)/2)
916 		return -EINVAL;
917 	rdev->size = le64_to_cpu(sb->data_size)/2;
918 	if (le32_to_cpu(sb->chunksize))
919 		rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
920 	return 0;
921 }
922 
923 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
924 {
925 	struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
926 
927 	rdev->raid_disk = -1;
928 	rdev->in_sync = 0;
929 	if (mddev->raid_disks == 0) {
930 		mddev->major_version = 1;
931 		mddev->patch_version = 0;
932 		mddev->persistent = 1;
933 		mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
934 		mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
935 		mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
936 		mddev->level = le32_to_cpu(sb->level);
937 		mddev->layout = le32_to_cpu(sb->layout);
938 		mddev->raid_disks = le32_to_cpu(sb->raid_disks);
939 		mddev->size = le64_to_cpu(sb->size)/2;
940 		mddev->events = le64_to_cpu(sb->events);
941 
942 		mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
943 		memcpy(mddev->uuid, sb->set_uuid, 16);
944 
945 		mddev->max_disks =  (4096-256)/2;
946 
947 		if ((le32_to_cpu(sb->feature_map) & 1) &&
948 		    mddev->bitmap_file == NULL ) {
949 			if (mddev->level != 1) {
950 				printk(KERN_WARNING "md: bitmaps only supported for raid1\n");
951 				return -EINVAL;
952 			}
953 			mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
954 		}
955 	} else if (mddev->pers == NULL) {
956 		/* Insist of good event counter while assembling */
957 		__u64 ev1 = le64_to_cpu(sb->events);
958 		++ev1;
959 		if (ev1 < mddev->events)
960 			return -EINVAL;
961 	} else if (mddev->bitmap) {
962 		/* If adding to array with a bitmap, then we can accept an
963 		 * older device, but not too old.
964 		 */
965 		__u64 ev1 = le64_to_cpu(sb->events);
966 		if (ev1 < mddev->bitmap->events_cleared)
967 			return 0;
968 	} else /* just a hot-add of a new device, leave raid_disk at -1 */
969 		return 0;
970 
971 	if (mddev->level != LEVEL_MULTIPATH) {
972 		int role;
973 		rdev->desc_nr = le32_to_cpu(sb->dev_number);
974 		role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
975 		switch(role) {
976 		case 0xffff: /* spare */
977 			rdev->faulty = 0;
978 			break;
979 		case 0xfffe: /* faulty */
980 			rdev->faulty = 1;
981 			break;
982 		default:
983 			rdev->in_sync = 1;
984 			rdev->faulty = 0;
985 			rdev->raid_disk = role;
986 			break;
987 		}
988 	} else /* MULTIPATH are always insync */
989 		rdev->in_sync = 1;
990 
991 	return 0;
992 }
993 
994 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
995 {
996 	struct mdp_superblock_1 *sb;
997 	struct list_head *tmp;
998 	mdk_rdev_t *rdev2;
999 	int max_dev, i;
1000 	/* make rdev->sb match mddev and rdev data. */
1001 
1002 	sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1003 
1004 	sb->feature_map = 0;
1005 	sb->pad0 = 0;
1006 	memset(sb->pad1, 0, sizeof(sb->pad1));
1007 	memset(sb->pad2, 0, sizeof(sb->pad2));
1008 	memset(sb->pad3, 0, sizeof(sb->pad3));
1009 
1010 	sb->utime = cpu_to_le64((__u64)mddev->utime);
1011 	sb->events = cpu_to_le64(mddev->events);
1012 	if (mddev->in_sync)
1013 		sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1014 	else
1015 		sb->resync_offset = cpu_to_le64(0);
1016 
1017 	if (mddev->bitmap && mddev->bitmap_file == NULL) {
1018 		sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1019 		sb->feature_map = cpu_to_le32(1);
1020 	}
1021 
1022 	max_dev = 0;
1023 	ITERATE_RDEV(mddev,rdev2,tmp)
1024 		if (rdev2->desc_nr+1 > max_dev)
1025 			max_dev = rdev2->desc_nr+1;
1026 
1027 	sb->max_dev = cpu_to_le32(max_dev);
1028 	for (i=0; i<max_dev;i++)
1029 		sb->dev_roles[i] = cpu_to_le16(0xfffe);
1030 
1031 	ITERATE_RDEV(mddev,rdev2,tmp) {
1032 		i = rdev2->desc_nr;
1033 		if (rdev2->faulty)
1034 			sb->dev_roles[i] = cpu_to_le16(0xfffe);
1035 		else if (rdev2->in_sync)
1036 			sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1037 		else
1038 			sb->dev_roles[i] = cpu_to_le16(0xffff);
1039 	}
1040 
1041 	sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
1042 	sb->sb_csum = calc_sb_1_csum(sb);
1043 }
1044 
1045 
1046 static struct super_type super_types[] = {
1047 	[0] = {
1048 		.name	= "0.90.0",
1049 		.owner	= THIS_MODULE,
1050 		.load_super	= super_90_load,
1051 		.validate_super	= super_90_validate,
1052 		.sync_super	= super_90_sync,
1053 	},
1054 	[1] = {
1055 		.name	= "md-1",
1056 		.owner	= THIS_MODULE,
1057 		.load_super	= super_1_load,
1058 		.validate_super	= super_1_validate,
1059 		.sync_super	= super_1_sync,
1060 	},
1061 };
1062 
1063 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
1064 {
1065 	struct list_head *tmp;
1066 	mdk_rdev_t *rdev;
1067 
1068 	ITERATE_RDEV(mddev,rdev,tmp)
1069 		if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
1070 			return rdev;
1071 
1072 	return NULL;
1073 }
1074 
1075 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1076 {
1077 	struct list_head *tmp;
1078 	mdk_rdev_t *rdev;
1079 
1080 	ITERATE_RDEV(mddev1,rdev,tmp)
1081 		if (match_dev_unit(mddev2, rdev))
1082 			return 1;
1083 
1084 	return 0;
1085 }
1086 
1087 static LIST_HEAD(pending_raid_disks);
1088 
1089 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1090 {
1091 	mdk_rdev_t *same_pdev;
1092 	char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1093 
1094 	if (rdev->mddev) {
1095 		MD_BUG();
1096 		return -EINVAL;
1097 	}
1098 	same_pdev = match_dev_unit(mddev, rdev);
1099 	if (same_pdev)
1100 		printk(KERN_WARNING
1101 			"%s: WARNING: %s appears to be on the same physical"
1102 	 		" disk as %s. True\n     protection against single-disk"
1103 			" failure might be compromised.\n",
1104 			mdname(mddev), bdevname(rdev->bdev,b),
1105 			bdevname(same_pdev->bdev,b2));
1106 
1107 	/* Verify rdev->desc_nr is unique.
1108 	 * If it is -1, assign a free number, else
1109 	 * check number is not in use
1110 	 */
1111 	if (rdev->desc_nr < 0) {
1112 		int choice = 0;
1113 		if (mddev->pers) choice = mddev->raid_disks;
1114 		while (find_rdev_nr(mddev, choice))
1115 			choice++;
1116 		rdev->desc_nr = choice;
1117 	} else {
1118 		if (find_rdev_nr(mddev, rdev->desc_nr))
1119 			return -EBUSY;
1120 	}
1121 
1122 	list_add(&rdev->same_set, &mddev->disks);
1123 	rdev->mddev = mddev;
1124 	printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
1125 	return 0;
1126 }
1127 
1128 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1129 {
1130 	char b[BDEVNAME_SIZE];
1131 	if (!rdev->mddev) {
1132 		MD_BUG();
1133 		return;
1134 	}
1135 	list_del_init(&rdev->same_set);
1136 	printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1137 	rdev->mddev = NULL;
1138 }
1139 
1140 /*
1141  * prevent the device from being mounted, repartitioned or
1142  * otherwise reused by a RAID array (or any other kernel
1143  * subsystem), by bd_claiming the device.
1144  */
1145 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1146 {
1147 	int err = 0;
1148 	struct block_device *bdev;
1149 	char b[BDEVNAME_SIZE];
1150 
1151 	bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1152 	if (IS_ERR(bdev)) {
1153 		printk(KERN_ERR "md: could not open %s.\n",
1154 			__bdevname(dev, b));
1155 		return PTR_ERR(bdev);
1156 	}
1157 	err = bd_claim(bdev, rdev);
1158 	if (err) {
1159 		printk(KERN_ERR "md: could not bd_claim %s.\n",
1160 			bdevname(bdev, b));
1161 		blkdev_put(bdev);
1162 		return err;
1163 	}
1164 	rdev->bdev = bdev;
1165 	return err;
1166 }
1167 
1168 static void unlock_rdev(mdk_rdev_t *rdev)
1169 {
1170 	struct block_device *bdev = rdev->bdev;
1171 	rdev->bdev = NULL;
1172 	if (!bdev)
1173 		MD_BUG();
1174 	bd_release(bdev);
1175 	blkdev_put(bdev);
1176 }
1177 
1178 void md_autodetect_dev(dev_t dev);
1179 
1180 static void export_rdev(mdk_rdev_t * rdev)
1181 {
1182 	char b[BDEVNAME_SIZE];
1183 	printk(KERN_INFO "md: export_rdev(%s)\n",
1184 		bdevname(rdev->bdev,b));
1185 	if (rdev->mddev)
1186 		MD_BUG();
1187 	free_disk_sb(rdev);
1188 	list_del_init(&rdev->same_set);
1189 #ifndef MODULE
1190 	md_autodetect_dev(rdev->bdev->bd_dev);
1191 #endif
1192 	unlock_rdev(rdev);
1193 	kfree(rdev);
1194 }
1195 
1196 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1197 {
1198 	unbind_rdev_from_array(rdev);
1199 	export_rdev(rdev);
1200 }
1201 
1202 static void export_array(mddev_t *mddev)
1203 {
1204 	struct list_head *tmp;
1205 	mdk_rdev_t *rdev;
1206 
1207 	ITERATE_RDEV(mddev,rdev,tmp) {
1208 		if (!rdev->mddev) {
1209 			MD_BUG();
1210 			continue;
1211 		}
1212 		kick_rdev_from_array(rdev);
1213 	}
1214 	if (!list_empty(&mddev->disks))
1215 		MD_BUG();
1216 	mddev->raid_disks = 0;
1217 	mddev->major_version = 0;
1218 }
1219 
1220 static void print_desc(mdp_disk_t *desc)
1221 {
1222 	printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1223 		desc->major,desc->minor,desc->raid_disk,desc->state);
1224 }
1225 
1226 static void print_sb(mdp_super_t *sb)
1227 {
1228 	int i;
1229 
1230 	printk(KERN_INFO
1231 		"md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1232 		sb->major_version, sb->minor_version, sb->patch_version,
1233 		sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1234 		sb->ctime);
1235 	printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1236 		sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1237 		sb->md_minor, sb->layout, sb->chunk_size);
1238 	printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1239 		" FD:%d SD:%d CSUM:%08x E:%08lx\n",
1240 		sb->utime, sb->state, sb->active_disks, sb->working_disks,
1241 		sb->failed_disks, sb->spare_disks,
1242 		sb->sb_csum, (unsigned long)sb->events_lo);
1243 
1244 	printk(KERN_INFO);
1245 	for (i = 0; i < MD_SB_DISKS; i++) {
1246 		mdp_disk_t *desc;
1247 
1248 		desc = sb->disks + i;
1249 		if (desc->number || desc->major || desc->minor ||
1250 		    desc->raid_disk || (desc->state && (desc->state != 4))) {
1251 			printk("     D %2d: ", i);
1252 			print_desc(desc);
1253 		}
1254 	}
1255 	printk(KERN_INFO "md:     THIS: ");
1256 	print_desc(&sb->this_disk);
1257 
1258 }
1259 
1260 static void print_rdev(mdk_rdev_t *rdev)
1261 {
1262 	char b[BDEVNAME_SIZE];
1263 	printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1264 		bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1265 	       	rdev->faulty, rdev->in_sync, rdev->desc_nr);
1266 	if (rdev->sb_loaded) {
1267 		printk(KERN_INFO "md: rdev superblock:\n");
1268 		print_sb((mdp_super_t*)page_address(rdev->sb_page));
1269 	} else
1270 		printk(KERN_INFO "md: no rdev superblock!\n");
1271 }
1272 
1273 void md_print_devices(void)
1274 {
1275 	struct list_head *tmp, *tmp2;
1276 	mdk_rdev_t *rdev;
1277 	mddev_t *mddev;
1278 	char b[BDEVNAME_SIZE];
1279 
1280 	printk("\n");
1281 	printk("md:	**********************************\n");
1282 	printk("md:	* <COMPLETE RAID STATE PRINTOUT> *\n");
1283 	printk("md:	**********************************\n");
1284 	ITERATE_MDDEV(mddev,tmp) {
1285 
1286 		if (mddev->bitmap)
1287 			bitmap_print_sb(mddev->bitmap);
1288 		else
1289 			printk("%s: ", mdname(mddev));
1290 		ITERATE_RDEV(mddev,rdev,tmp2)
1291 			printk("<%s>", bdevname(rdev->bdev,b));
1292 		printk("\n");
1293 
1294 		ITERATE_RDEV(mddev,rdev,tmp2)
1295 			print_rdev(rdev);
1296 	}
1297 	printk("md:	**********************************\n");
1298 	printk("\n");
1299 }
1300 
1301 
1302 static void sync_sbs(mddev_t * mddev)
1303 {
1304 	mdk_rdev_t *rdev;
1305 	struct list_head *tmp;
1306 
1307 	ITERATE_RDEV(mddev,rdev,tmp) {
1308 		super_types[mddev->major_version].
1309 			sync_super(mddev, rdev);
1310 		rdev->sb_loaded = 1;
1311 	}
1312 }
1313 
1314 static void md_update_sb(mddev_t * mddev)
1315 {
1316 	int err;
1317 	struct list_head *tmp;
1318 	mdk_rdev_t *rdev;
1319 	int sync_req;
1320 
1321 repeat:
1322 	spin_lock(&mddev->write_lock);
1323 	sync_req = mddev->in_sync;
1324 	mddev->utime = get_seconds();
1325 	mddev->events ++;
1326 
1327 	if (!mddev->events) {
1328 		/*
1329 		 * oops, this 64-bit counter should never wrap.
1330 		 * Either we are in around ~1 trillion A.C., assuming
1331 		 * 1 reboot per second, or we have a bug:
1332 		 */
1333 		MD_BUG();
1334 		mddev->events --;
1335 	}
1336 	mddev->sb_dirty = 2;
1337 	sync_sbs(mddev);
1338 
1339 	/*
1340 	 * do not write anything to disk if using
1341 	 * nonpersistent superblocks
1342 	 */
1343 	if (!mddev->persistent) {
1344 		mddev->sb_dirty = 0;
1345 		spin_unlock(&mddev->write_lock);
1346 		wake_up(&mddev->sb_wait);
1347 		return;
1348 	}
1349 	spin_unlock(&mddev->write_lock);
1350 
1351 	dprintk(KERN_INFO
1352 		"md: updating %s RAID superblock on device (in sync %d)\n",
1353 		mdname(mddev),mddev->in_sync);
1354 
1355 	err = bitmap_update_sb(mddev->bitmap);
1356 	ITERATE_RDEV(mddev,rdev,tmp) {
1357 		char b[BDEVNAME_SIZE];
1358 		dprintk(KERN_INFO "md: ");
1359 		if (rdev->faulty)
1360 			dprintk("(skipping faulty ");
1361 
1362 		dprintk("%s ", bdevname(rdev->bdev,b));
1363 		if (!rdev->faulty) {
1364 			md_super_write(mddev,rdev,
1365 				       rdev->sb_offset<<1, MD_SB_BYTES,
1366 				       rdev->sb_page);
1367 			dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1368 				bdevname(rdev->bdev,b),
1369 				(unsigned long long)rdev->sb_offset);
1370 
1371 		} else
1372 			dprintk(")\n");
1373 		if (mddev->level == LEVEL_MULTIPATH)
1374 			/* only need to write one superblock... */
1375 			break;
1376 	}
1377 	wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
1378 	/* if there was a failure, sb_dirty was set to 1, and we re-write super */
1379 
1380 	spin_lock(&mddev->write_lock);
1381 	if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
1382 		/* have to write it out again */
1383 		spin_unlock(&mddev->write_lock);
1384 		goto repeat;
1385 	}
1386 	mddev->sb_dirty = 0;
1387 	spin_unlock(&mddev->write_lock);
1388 	wake_up(&mddev->sb_wait);
1389 
1390 }
1391 
1392 /*
1393  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1394  *
1395  * mark the device faulty if:
1396  *
1397  *   - the device is nonexistent (zero size)
1398  *   - the device has no valid superblock
1399  *
1400  * a faulty rdev _never_ has rdev->sb set.
1401  */
1402 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1403 {
1404 	char b[BDEVNAME_SIZE];
1405 	int err;
1406 	mdk_rdev_t *rdev;
1407 	sector_t size;
1408 
1409 	rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
1410 	if (!rdev) {
1411 		printk(KERN_ERR "md: could not alloc mem for new device!\n");
1412 		return ERR_PTR(-ENOMEM);
1413 	}
1414 	memset(rdev, 0, sizeof(*rdev));
1415 
1416 	if ((err = alloc_disk_sb(rdev)))
1417 		goto abort_free;
1418 
1419 	err = lock_rdev(rdev, newdev);
1420 	if (err)
1421 		goto abort_free;
1422 
1423 	rdev->desc_nr = -1;
1424 	rdev->faulty = 0;
1425 	rdev->in_sync = 0;
1426 	rdev->data_offset = 0;
1427 	atomic_set(&rdev->nr_pending, 0);
1428 
1429 	size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1430 	if (!size) {
1431 		printk(KERN_WARNING
1432 			"md: %s has zero or unknown size, marking faulty!\n",
1433 			bdevname(rdev->bdev,b));
1434 		err = -EINVAL;
1435 		goto abort_free;
1436 	}
1437 
1438 	if (super_format >= 0) {
1439 		err = super_types[super_format].
1440 			load_super(rdev, NULL, super_minor);
1441 		if (err == -EINVAL) {
1442 			printk(KERN_WARNING
1443 				"md: %s has invalid sb, not importing!\n",
1444 				bdevname(rdev->bdev,b));
1445 			goto abort_free;
1446 		}
1447 		if (err < 0) {
1448 			printk(KERN_WARNING
1449 				"md: could not read %s's sb, not importing!\n",
1450 				bdevname(rdev->bdev,b));
1451 			goto abort_free;
1452 		}
1453 	}
1454 	INIT_LIST_HEAD(&rdev->same_set);
1455 
1456 	return rdev;
1457 
1458 abort_free:
1459 	if (rdev->sb_page) {
1460 		if (rdev->bdev)
1461 			unlock_rdev(rdev);
1462 		free_disk_sb(rdev);
1463 	}
1464 	kfree(rdev);
1465 	return ERR_PTR(err);
1466 }
1467 
1468 /*
1469  * Check a full RAID array for plausibility
1470  */
1471 
1472 
1473 static void analyze_sbs(mddev_t * mddev)
1474 {
1475 	int i;
1476 	struct list_head *tmp;
1477 	mdk_rdev_t *rdev, *freshest;
1478 	char b[BDEVNAME_SIZE];
1479 
1480 	freshest = NULL;
1481 	ITERATE_RDEV(mddev,rdev,tmp)
1482 		switch (super_types[mddev->major_version].
1483 			load_super(rdev, freshest, mddev->minor_version)) {
1484 		case 1:
1485 			freshest = rdev;
1486 			break;
1487 		case 0:
1488 			break;
1489 		default:
1490 			printk( KERN_ERR \
1491 				"md: fatal superblock inconsistency in %s"
1492 				" -- removing from array\n",
1493 				bdevname(rdev->bdev,b));
1494 			kick_rdev_from_array(rdev);
1495 		}
1496 
1497 
1498 	super_types[mddev->major_version].
1499 		validate_super(mddev, freshest);
1500 
1501 	i = 0;
1502 	ITERATE_RDEV(mddev,rdev,tmp) {
1503 		if (rdev != freshest)
1504 			if (super_types[mddev->major_version].
1505 			    validate_super(mddev, rdev)) {
1506 				printk(KERN_WARNING "md: kicking non-fresh %s"
1507 					" from array!\n",
1508 					bdevname(rdev->bdev,b));
1509 				kick_rdev_from_array(rdev);
1510 				continue;
1511 			}
1512 		if (mddev->level == LEVEL_MULTIPATH) {
1513 			rdev->desc_nr = i++;
1514 			rdev->raid_disk = rdev->desc_nr;
1515 			rdev->in_sync = 1;
1516 		}
1517 	}
1518 
1519 
1520 
1521 	if (mddev->recovery_cp != MaxSector &&
1522 	    mddev->level >= 1)
1523 		printk(KERN_ERR "md: %s: raid array is not clean"
1524 		       " -- starting background reconstruction\n",
1525 		       mdname(mddev));
1526 
1527 }
1528 
1529 int mdp_major = 0;
1530 
1531 static struct kobject *md_probe(dev_t dev, int *part, void *data)
1532 {
1533 	static DECLARE_MUTEX(disks_sem);
1534 	mddev_t *mddev = mddev_find(dev);
1535 	struct gendisk *disk;
1536 	int partitioned = (MAJOR(dev) != MD_MAJOR);
1537 	int shift = partitioned ? MdpMinorShift : 0;
1538 	int unit = MINOR(dev) >> shift;
1539 
1540 	if (!mddev)
1541 		return NULL;
1542 
1543 	down(&disks_sem);
1544 	if (mddev->gendisk) {
1545 		up(&disks_sem);
1546 		mddev_put(mddev);
1547 		return NULL;
1548 	}
1549 	disk = alloc_disk(1 << shift);
1550 	if (!disk) {
1551 		up(&disks_sem);
1552 		mddev_put(mddev);
1553 		return NULL;
1554 	}
1555 	disk->major = MAJOR(dev);
1556 	disk->first_minor = unit << shift;
1557 	if (partitioned) {
1558 		sprintf(disk->disk_name, "md_d%d", unit);
1559 		sprintf(disk->devfs_name, "md/d%d", unit);
1560 	} else {
1561 		sprintf(disk->disk_name, "md%d", unit);
1562 		sprintf(disk->devfs_name, "md/%d", unit);
1563 	}
1564 	disk->fops = &md_fops;
1565 	disk->private_data = mddev;
1566 	disk->queue = mddev->queue;
1567 	add_disk(disk);
1568 	mddev->gendisk = disk;
1569 	up(&disks_sem);
1570 	return NULL;
1571 }
1572 
1573 void md_wakeup_thread(mdk_thread_t *thread);
1574 
1575 static void md_safemode_timeout(unsigned long data)
1576 {
1577 	mddev_t *mddev = (mddev_t *) data;
1578 
1579 	mddev->safemode = 1;
1580 	md_wakeup_thread(mddev->thread);
1581 }
1582 
1583 
1584 static int do_md_run(mddev_t * mddev)
1585 {
1586 	int pnum, err;
1587 	int chunk_size;
1588 	struct list_head *tmp;
1589 	mdk_rdev_t *rdev;
1590 	struct gendisk *disk;
1591 	char b[BDEVNAME_SIZE];
1592 
1593 	if (list_empty(&mddev->disks))
1594 		/* cannot run an array with no devices.. */
1595 		return -EINVAL;
1596 
1597 	if (mddev->pers)
1598 		return -EBUSY;
1599 
1600 	/*
1601 	 * Analyze all RAID superblock(s)
1602 	 */
1603 	if (!mddev->raid_disks)
1604 		analyze_sbs(mddev);
1605 
1606 	chunk_size = mddev->chunk_size;
1607 	pnum = level_to_pers(mddev->level);
1608 
1609 	if ((pnum != MULTIPATH) && (pnum != RAID1)) {
1610 		if (!chunk_size) {
1611 			/*
1612 			 * 'default chunksize' in the old md code used to
1613 			 * be PAGE_SIZE, baaad.
1614 			 * we abort here to be on the safe side. We don't
1615 			 * want to continue the bad practice.
1616 			 */
1617 			printk(KERN_ERR
1618 				"no chunksize specified, see 'man raidtab'\n");
1619 			return -EINVAL;
1620 		}
1621 		if (chunk_size > MAX_CHUNK_SIZE) {
1622 			printk(KERN_ERR "too big chunk_size: %d > %d\n",
1623 				chunk_size, MAX_CHUNK_SIZE);
1624 			return -EINVAL;
1625 		}
1626 		/*
1627 		 * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
1628 		 */
1629 		if ( (1 << ffz(~chunk_size)) != chunk_size) {
1630 			printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
1631 			return -EINVAL;
1632 		}
1633 		if (chunk_size < PAGE_SIZE) {
1634 			printk(KERN_ERR "too small chunk_size: %d < %ld\n",
1635 				chunk_size, PAGE_SIZE);
1636 			return -EINVAL;
1637 		}
1638 
1639 		/* devices must have minimum size of one chunk */
1640 		ITERATE_RDEV(mddev,rdev,tmp) {
1641 			if (rdev->faulty)
1642 				continue;
1643 			if (rdev->size < chunk_size / 1024) {
1644 				printk(KERN_WARNING
1645 					"md: Dev %s smaller than chunk_size:"
1646 					" %lluk < %dk\n",
1647 					bdevname(rdev->bdev,b),
1648 					(unsigned long long)rdev->size,
1649 					chunk_size / 1024);
1650 				return -EINVAL;
1651 			}
1652 		}
1653 	}
1654 
1655 #ifdef CONFIG_KMOD
1656 	if (!pers[pnum])
1657 	{
1658 		request_module("md-personality-%d", pnum);
1659 	}
1660 #endif
1661 
1662 	/*
1663 	 * Drop all container device buffers, from now on
1664 	 * the only valid external interface is through the md
1665 	 * device.
1666 	 * Also find largest hardsector size
1667 	 */
1668 	ITERATE_RDEV(mddev,rdev,tmp) {
1669 		if (rdev->faulty)
1670 			continue;
1671 		sync_blockdev(rdev->bdev);
1672 		invalidate_bdev(rdev->bdev, 0);
1673 	}
1674 
1675 	md_probe(mddev->unit, NULL, NULL);
1676 	disk = mddev->gendisk;
1677 	if (!disk)
1678 		return -ENOMEM;
1679 
1680 	spin_lock(&pers_lock);
1681 	if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
1682 		spin_unlock(&pers_lock);
1683 		printk(KERN_WARNING "md: personality %d is not loaded!\n",
1684 		       pnum);
1685 		return -EINVAL;
1686 	}
1687 
1688 	mddev->pers = pers[pnum];
1689 	spin_unlock(&pers_lock);
1690 
1691 	mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
1692 
1693 	/* before we start the array running, initialise the bitmap */
1694 	err = bitmap_create(mddev);
1695 	if (err)
1696 		printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
1697 			mdname(mddev), err);
1698 	else
1699 		err = mddev->pers->run(mddev);
1700 	if (err) {
1701 		printk(KERN_ERR "md: pers->run() failed ...\n");
1702 		module_put(mddev->pers->owner);
1703 		mddev->pers = NULL;
1704 		bitmap_destroy(mddev);
1705 		return err;
1706 	}
1707  	atomic_set(&mddev->writes_pending,0);
1708 	mddev->safemode = 0;
1709 	mddev->safemode_timer.function = md_safemode_timeout;
1710 	mddev->safemode_timer.data = (unsigned long) mddev;
1711 	mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
1712 	mddev->in_sync = 1;
1713 
1714 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1715 
1716 	if (mddev->sb_dirty)
1717 		md_update_sb(mddev);
1718 
1719 	set_capacity(disk, mddev->array_size<<1);
1720 
1721 	/* If we call blk_queue_make_request here, it will
1722 	 * re-initialise max_sectors etc which may have been
1723 	 * refined inside -> run.  So just set the bits we need to set.
1724 	 * Most initialisation happended when we called
1725 	 * blk_queue_make_request(..., md_fail_request)
1726 	 * earlier.
1727 	 */
1728 	mddev->queue->queuedata = mddev;
1729 	mddev->queue->make_request_fn = mddev->pers->make_request;
1730 
1731 	mddev->changed = 1;
1732 	return 0;
1733 }
1734 
1735 static int restart_array(mddev_t *mddev)
1736 {
1737 	struct gendisk *disk = mddev->gendisk;
1738 	int err;
1739 
1740 	/*
1741 	 * Complain if it has no devices
1742 	 */
1743 	err = -ENXIO;
1744 	if (list_empty(&mddev->disks))
1745 		goto out;
1746 
1747 	if (mddev->pers) {
1748 		err = -EBUSY;
1749 		if (!mddev->ro)
1750 			goto out;
1751 
1752 		mddev->safemode = 0;
1753 		mddev->ro = 0;
1754 		set_disk_ro(disk, 0);
1755 
1756 		printk(KERN_INFO "md: %s switched to read-write mode.\n",
1757 			mdname(mddev));
1758 		/*
1759 		 * Kick recovery or resync if necessary
1760 		 */
1761 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
1762 		md_wakeup_thread(mddev->thread);
1763 		err = 0;
1764 	} else {
1765 		printk(KERN_ERR "md: %s has no personality assigned.\n",
1766 			mdname(mddev));
1767 		err = -EINVAL;
1768 	}
1769 
1770 out:
1771 	return err;
1772 }
1773 
1774 static int do_md_stop(mddev_t * mddev, int ro)
1775 {
1776 	int err = 0;
1777 	struct gendisk *disk = mddev->gendisk;
1778 
1779 	if (mddev->pers) {
1780 		if (atomic_read(&mddev->active)>2) {
1781 			printk("md: %s still in use.\n",mdname(mddev));
1782 			return -EBUSY;
1783 		}
1784 
1785 		if (mddev->sync_thread) {
1786 			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1787 			md_unregister_thread(mddev->sync_thread);
1788 			mddev->sync_thread = NULL;
1789 		}
1790 
1791 		del_timer_sync(&mddev->safemode_timer);
1792 
1793 		invalidate_partition(disk, 0);
1794 
1795 		if (ro) {
1796 			err  = -ENXIO;
1797 			if (mddev->ro)
1798 				goto out;
1799 			mddev->ro = 1;
1800 		} else {
1801 			if (mddev->ro)
1802 				set_disk_ro(disk, 0);
1803 			blk_queue_make_request(mddev->queue, md_fail_request);
1804 			mddev->pers->stop(mddev);
1805 			module_put(mddev->pers->owner);
1806 			mddev->pers = NULL;
1807 			if (mddev->ro)
1808 				mddev->ro = 0;
1809 		}
1810 		if (!mddev->in_sync) {
1811 			/* mark array as shutdown cleanly */
1812 			mddev->in_sync = 1;
1813 			md_update_sb(mddev);
1814 		}
1815 		if (ro)
1816 			set_disk_ro(disk, 1);
1817 	}
1818 
1819 	bitmap_destroy(mddev);
1820 	if (mddev->bitmap_file) {
1821 		atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
1822 		fput(mddev->bitmap_file);
1823 		mddev->bitmap_file = NULL;
1824 	}
1825 
1826 	/*
1827 	 * Free resources if final stop
1828 	 */
1829 	if (!ro) {
1830 		struct gendisk *disk;
1831 		printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
1832 
1833 		export_array(mddev);
1834 
1835 		mddev->array_size = 0;
1836 		disk = mddev->gendisk;
1837 		if (disk)
1838 			set_capacity(disk, 0);
1839 		mddev->changed = 1;
1840 	} else
1841 		printk(KERN_INFO "md: %s switched to read-only mode.\n",
1842 			mdname(mddev));
1843 	err = 0;
1844 out:
1845 	return err;
1846 }
1847 
1848 static void autorun_array(mddev_t *mddev)
1849 {
1850 	mdk_rdev_t *rdev;
1851 	struct list_head *tmp;
1852 	int err;
1853 
1854 	if (list_empty(&mddev->disks))
1855 		return;
1856 
1857 	printk(KERN_INFO "md: running: ");
1858 
1859 	ITERATE_RDEV(mddev,rdev,tmp) {
1860 		char b[BDEVNAME_SIZE];
1861 		printk("<%s>", bdevname(rdev->bdev,b));
1862 	}
1863 	printk("\n");
1864 
1865 	err = do_md_run (mddev);
1866 	if (err) {
1867 		printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
1868 		do_md_stop (mddev, 0);
1869 	}
1870 }
1871 
1872 /*
1873  * lets try to run arrays based on all disks that have arrived
1874  * until now. (those are in pending_raid_disks)
1875  *
1876  * the method: pick the first pending disk, collect all disks with
1877  * the same UUID, remove all from the pending list and put them into
1878  * the 'same_array' list. Then order this list based on superblock
1879  * update time (freshest comes first), kick out 'old' disks and
1880  * compare superblocks. If everything's fine then run it.
1881  *
1882  * If "unit" is allocated, then bump its reference count
1883  */
1884 static void autorun_devices(int part)
1885 {
1886 	struct list_head candidates;
1887 	struct list_head *tmp;
1888 	mdk_rdev_t *rdev0, *rdev;
1889 	mddev_t *mddev;
1890 	char b[BDEVNAME_SIZE];
1891 
1892 	printk(KERN_INFO "md: autorun ...\n");
1893 	while (!list_empty(&pending_raid_disks)) {
1894 		dev_t dev;
1895 		rdev0 = list_entry(pending_raid_disks.next,
1896 					 mdk_rdev_t, same_set);
1897 
1898 		printk(KERN_INFO "md: considering %s ...\n",
1899 			bdevname(rdev0->bdev,b));
1900 		INIT_LIST_HEAD(&candidates);
1901 		ITERATE_RDEV_PENDING(rdev,tmp)
1902 			if (super_90_load(rdev, rdev0, 0) >= 0) {
1903 				printk(KERN_INFO "md:  adding %s ...\n",
1904 					bdevname(rdev->bdev,b));
1905 				list_move(&rdev->same_set, &candidates);
1906 			}
1907 		/*
1908 		 * now we have a set of devices, with all of them having
1909 		 * mostly sane superblocks. It's time to allocate the
1910 		 * mddev.
1911 		 */
1912 		if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
1913 			printk(KERN_INFO "md: unit number in %s is bad: %d\n",
1914 			       bdevname(rdev0->bdev, b), rdev0->preferred_minor);
1915 			break;
1916 		}
1917 		if (part)
1918 			dev = MKDEV(mdp_major,
1919 				    rdev0->preferred_minor << MdpMinorShift);
1920 		else
1921 			dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
1922 
1923 		md_probe(dev, NULL, NULL);
1924 		mddev = mddev_find(dev);
1925 		if (!mddev) {
1926 			printk(KERN_ERR
1927 				"md: cannot allocate memory for md drive.\n");
1928 			break;
1929 		}
1930 		if (mddev_lock(mddev))
1931 			printk(KERN_WARNING "md: %s locked, cannot run\n",
1932 			       mdname(mddev));
1933 		else if (mddev->raid_disks || mddev->major_version
1934 			 || !list_empty(&mddev->disks)) {
1935 			printk(KERN_WARNING
1936 				"md: %s already running, cannot run %s\n",
1937 				mdname(mddev), bdevname(rdev0->bdev,b));
1938 			mddev_unlock(mddev);
1939 		} else {
1940 			printk(KERN_INFO "md: created %s\n", mdname(mddev));
1941 			ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
1942 				list_del_init(&rdev->same_set);
1943 				if (bind_rdev_to_array(rdev, mddev))
1944 					export_rdev(rdev);
1945 			}
1946 			autorun_array(mddev);
1947 			mddev_unlock(mddev);
1948 		}
1949 		/* on success, candidates will be empty, on error
1950 		 * it won't...
1951 		 */
1952 		ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
1953 			export_rdev(rdev);
1954 		mddev_put(mddev);
1955 	}
1956 	printk(KERN_INFO "md: ... autorun DONE.\n");
1957 }
1958 
1959 /*
1960  * import RAID devices based on one partition
1961  * if possible, the array gets run as well.
1962  */
1963 
1964 static int autostart_array(dev_t startdev)
1965 {
1966 	char b[BDEVNAME_SIZE];
1967 	int err = -EINVAL, i;
1968 	mdp_super_t *sb = NULL;
1969 	mdk_rdev_t *start_rdev = NULL, *rdev;
1970 
1971 	start_rdev = md_import_device(startdev, 0, 0);
1972 	if (IS_ERR(start_rdev))
1973 		return err;
1974 
1975 
1976 	/* NOTE: this can only work for 0.90.0 superblocks */
1977 	sb = (mdp_super_t*)page_address(start_rdev->sb_page);
1978 	if (sb->major_version != 0 ||
1979 	    sb->minor_version != 90 ) {
1980 		printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
1981 		export_rdev(start_rdev);
1982 		return err;
1983 	}
1984 
1985 	if (start_rdev->faulty) {
1986 		printk(KERN_WARNING
1987 			"md: can not autostart based on faulty %s!\n",
1988 			bdevname(start_rdev->bdev,b));
1989 		export_rdev(start_rdev);
1990 		return err;
1991 	}
1992 	list_add(&start_rdev->same_set, &pending_raid_disks);
1993 
1994 	for (i = 0; i < MD_SB_DISKS; i++) {
1995 		mdp_disk_t *desc = sb->disks + i;
1996 		dev_t dev = MKDEV(desc->major, desc->minor);
1997 
1998 		if (!dev)
1999 			continue;
2000 		if (dev == startdev)
2001 			continue;
2002 		if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
2003 			continue;
2004 		rdev = md_import_device(dev, 0, 0);
2005 		if (IS_ERR(rdev))
2006 			continue;
2007 
2008 		list_add(&rdev->same_set, &pending_raid_disks);
2009 	}
2010 
2011 	/*
2012 	 * possibly return codes
2013 	 */
2014 	autorun_devices(0);
2015 	return 0;
2016 
2017 }
2018 
2019 
2020 static int get_version(void __user * arg)
2021 {
2022 	mdu_version_t ver;
2023 
2024 	ver.major = MD_MAJOR_VERSION;
2025 	ver.minor = MD_MINOR_VERSION;
2026 	ver.patchlevel = MD_PATCHLEVEL_VERSION;
2027 
2028 	if (copy_to_user(arg, &ver, sizeof(ver)))
2029 		return -EFAULT;
2030 
2031 	return 0;
2032 }
2033 
2034 static int get_array_info(mddev_t * mddev, void __user * arg)
2035 {
2036 	mdu_array_info_t info;
2037 	int nr,working,active,failed,spare;
2038 	mdk_rdev_t *rdev;
2039 	struct list_head *tmp;
2040 
2041 	nr=working=active=failed=spare=0;
2042 	ITERATE_RDEV(mddev,rdev,tmp) {
2043 		nr++;
2044 		if (rdev->faulty)
2045 			failed++;
2046 		else {
2047 			working++;
2048 			if (rdev->in_sync)
2049 				active++;
2050 			else
2051 				spare++;
2052 		}
2053 	}
2054 
2055 	info.major_version = mddev->major_version;
2056 	info.minor_version = mddev->minor_version;
2057 	info.patch_version = MD_PATCHLEVEL_VERSION;
2058 	info.ctime         = mddev->ctime;
2059 	info.level         = mddev->level;
2060 	info.size          = mddev->size;
2061 	info.nr_disks      = nr;
2062 	info.raid_disks    = mddev->raid_disks;
2063 	info.md_minor      = mddev->md_minor;
2064 	info.not_persistent= !mddev->persistent;
2065 
2066 	info.utime         = mddev->utime;
2067 	info.state         = 0;
2068 	if (mddev->in_sync)
2069 		info.state = (1<<MD_SB_CLEAN);
2070 	info.active_disks  = active;
2071 	info.working_disks = working;
2072 	info.failed_disks  = failed;
2073 	info.spare_disks   = spare;
2074 
2075 	info.layout        = mddev->layout;
2076 	info.chunk_size    = mddev->chunk_size;
2077 
2078 	if (copy_to_user(arg, &info, sizeof(info)))
2079 		return -EFAULT;
2080 
2081 	return 0;
2082 }
2083 
2084 static int get_bitmap_file(mddev_t * mddev, void * arg)
2085 {
2086 	mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
2087 	char *ptr, *buf = NULL;
2088 	int err = -ENOMEM;
2089 
2090 	file = kmalloc(sizeof(*file), GFP_KERNEL);
2091 	if (!file)
2092 		goto out;
2093 
2094 	/* bitmap disabled, zero the first byte and copy out */
2095 	if (!mddev->bitmap || !mddev->bitmap->file) {
2096 		file->pathname[0] = '\0';
2097 		goto copy_out;
2098 	}
2099 
2100 	buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
2101 	if (!buf)
2102 		goto out;
2103 
2104 	ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
2105 	if (!ptr)
2106 		goto out;
2107 
2108 	strcpy(file->pathname, ptr);
2109 
2110 copy_out:
2111 	err = 0;
2112 	if (copy_to_user(arg, file, sizeof(*file)))
2113 		err = -EFAULT;
2114 out:
2115 	kfree(buf);
2116 	kfree(file);
2117 	return err;
2118 }
2119 
2120 static int get_disk_info(mddev_t * mddev, void __user * arg)
2121 {
2122 	mdu_disk_info_t info;
2123 	unsigned int nr;
2124 	mdk_rdev_t *rdev;
2125 
2126 	if (copy_from_user(&info, arg, sizeof(info)))
2127 		return -EFAULT;
2128 
2129 	nr = info.number;
2130 
2131 	rdev = find_rdev_nr(mddev, nr);
2132 	if (rdev) {
2133 		info.major = MAJOR(rdev->bdev->bd_dev);
2134 		info.minor = MINOR(rdev->bdev->bd_dev);
2135 		info.raid_disk = rdev->raid_disk;
2136 		info.state = 0;
2137 		if (rdev->faulty)
2138 			info.state |= (1<<MD_DISK_FAULTY);
2139 		else if (rdev->in_sync) {
2140 			info.state |= (1<<MD_DISK_ACTIVE);
2141 			info.state |= (1<<MD_DISK_SYNC);
2142 		}
2143 	} else {
2144 		info.major = info.minor = 0;
2145 		info.raid_disk = -1;
2146 		info.state = (1<<MD_DISK_REMOVED);
2147 	}
2148 
2149 	if (copy_to_user(arg, &info, sizeof(info)))
2150 		return -EFAULT;
2151 
2152 	return 0;
2153 }
2154 
2155 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
2156 {
2157 	char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
2158 	mdk_rdev_t *rdev;
2159 	dev_t dev = MKDEV(info->major,info->minor);
2160 
2161 	if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
2162 		return -EOVERFLOW;
2163 
2164 	if (!mddev->raid_disks) {
2165 		int err;
2166 		/* expecting a device which has a superblock */
2167 		rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
2168 		if (IS_ERR(rdev)) {
2169 			printk(KERN_WARNING
2170 				"md: md_import_device returned %ld\n",
2171 				PTR_ERR(rdev));
2172 			return PTR_ERR(rdev);
2173 		}
2174 		if (!list_empty(&mddev->disks)) {
2175 			mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2176 							mdk_rdev_t, same_set);
2177 			int err = super_types[mddev->major_version]
2178 				.load_super(rdev, rdev0, mddev->minor_version);
2179 			if (err < 0) {
2180 				printk(KERN_WARNING
2181 					"md: %s has different UUID to %s\n",
2182 					bdevname(rdev->bdev,b),
2183 					bdevname(rdev0->bdev,b2));
2184 				export_rdev(rdev);
2185 				return -EINVAL;
2186 			}
2187 		}
2188 		err = bind_rdev_to_array(rdev, mddev);
2189 		if (err)
2190 			export_rdev(rdev);
2191 		return err;
2192 	}
2193 
2194 	/*
2195 	 * add_new_disk can be used once the array is assembled
2196 	 * to add "hot spares".  They must already have a superblock
2197 	 * written
2198 	 */
2199 	if (mddev->pers) {
2200 		int err;
2201 		if (!mddev->pers->hot_add_disk) {
2202 			printk(KERN_WARNING
2203 				"%s: personality does not support diskops!\n",
2204 			       mdname(mddev));
2205 			return -EINVAL;
2206 		}
2207 		rdev = md_import_device(dev, mddev->major_version,
2208 					mddev->minor_version);
2209 		if (IS_ERR(rdev)) {
2210 			printk(KERN_WARNING
2211 				"md: md_import_device returned %ld\n",
2212 				PTR_ERR(rdev));
2213 			return PTR_ERR(rdev);
2214 		}
2215 		/* set save_raid_disk if appropriate */
2216 		if (!mddev->persistent) {
2217 			if (info->state & (1<<MD_DISK_SYNC)  &&
2218 			    info->raid_disk < mddev->raid_disks)
2219 				rdev->raid_disk = info->raid_disk;
2220 			else
2221 				rdev->raid_disk = -1;
2222 		} else
2223 			super_types[mddev->major_version].
2224 				validate_super(mddev, rdev);
2225 		rdev->saved_raid_disk = rdev->raid_disk;
2226 
2227 		rdev->in_sync = 0; /* just to be sure */
2228 		rdev->raid_disk = -1;
2229 		err = bind_rdev_to_array(rdev, mddev);
2230 		if (err)
2231 			export_rdev(rdev);
2232 
2233 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2234 		if (mddev->thread)
2235 			md_wakeup_thread(mddev->thread);
2236 		return err;
2237 	}
2238 
2239 	/* otherwise, add_new_disk is only allowed
2240 	 * for major_version==0 superblocks
2241 	 */
2242 	if (mddev->major_version != 0) {
2243 		printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
2244 		       mdname(mddev));
2245 		return -EINVAL;
2246 	}
2247 
2248 	if (!(info->state & (1<<MD_DISK_FAULTY))) {
2249 		int err;
2250 		rdev = md_import_device (dev, -1, 0);
2251 		if (IS_ERR(rdev)) {
2252 			printk(KERN_WARNING
2253 				"md: error, md_import_device() returned %ld\n",
2254 				PTR_ERR(rdev));
2255 			return PTR_ERR(rdev);
2256 		}
2257 		rdev->desc_nr = info->number;
2258 		if (info->raid_disk < mddev->raid_disks)
2259 			rdev->raid_disk = info->raid_disk;
2260 		else
2261 			rdev->raid_disk = -1;
2262 
2263 		rdev->faulty = 0;
2264 		if (rdev->raid_disk < mddev->raid_disks)
2265 			rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
2266 		else
2267 			rdev->in_sync = 0;
2268 
2269 		err = bind_rdev_to_array(rdev, mddev);
2270 		if (err) {
2271 			export_rdev(rdev);
2272 			return err;
2273 		}
2274 
2275 		if (!mddev->persistent) {
2276 			printk(KERN_INFO "md: nonpersistent superblock ...\n");
2277 			rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2278 		} else
2279 			rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2280 		rdev->size = calc_dev_size(rdev, mddev->chunk_size);
2281 
2282 		if (!mddev->size || (mddev->size > rdev->size))
2283 			mddev->size = rdev->size;
2284 	}
2285 
2286 	return 0;
2287 }
2288 
2289 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
2290 {
2291 	char b[BDEVNAME_SIZE];
2292 	mdk_rdev_t *rdev;
2293 
2294 	if (!mddev->pers)
2295 		return -ENODEV;
2296 
2297 	rdev = find_rdev(mddev, dev);
2298 	if (!rdev)
2299 		return -ENXIO;
2300 
2301 	if (rdev->raid_disk >= 0)
2302 		goto busy;
2303 
2304 	kick_rdev_from_array(rdev);
2305 	md_update_sb(mddev);
2306 
2307 	return 0;
2308 busy:
2309 	printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
2310 		bdevname(rdev->bdev,b), mdname(mddev));
2311 	return -EBUSY;
2312 }
2313 
2314 static int hot_add_disk(mddev_t * mddev, dev_t dev)
2315 {
2316 	char b[BDEVNAME_SIZE];
2317 	int err;
2318 	unsigned int size;
2319 	mdk_rdev_t *rdev;
2320 
2321 	if (!mddev->pers)
2322 		return -ENODEV;
2323 
2324 	if (mddev->major_version != 0) {
2325 		printk(KERN_WARNING "%s: HOT_ADD may only be used with"
2326 			" version-0 superblocks.\n",
2327 			mdname(mddev));
2328 		return -EINVAL;
2329 	}
2330 	if (!mddev->pers->hot_add_disk) {
2331 		printk(KERN_WARNING
2332 			"%s: personality does not support diskops!\n",
2333 			mdname(mddev));
2334 		return -EINVAL;
2335 	}
2336 
2337 	rdev = md_import_device (dev, -1, 0);
2338 	if (IS_ERR(rdev)) {
2339 		printk(KERN_WARNING
2340 			"md: error, md_import_device() returned %ld\n",
2341 			PTR_ERR(rdev));
2342 		return -EINVAL;
2343 	}
2344 
2345 	if (mddev->persistent)
2346 		rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
2347 	else
2348 		rdev->sb_offset =
2349 			rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2350 
2351 	size = calc_dev_size(rdev, mddev->chunk_size);
2352 	rdev->size = size;
2353 
2354 	if (size < mddev->size) {
2355 		printk(KERN_WARNING
2356 			"%s: disk size %llu blocks < array size %llu\n",
2357 			mdname(mddev), (unsigned long long)size,
2358 			(unsigned long long)mddev->size);
2359 		err = -ENOSPC;
2360 		goto abort_export;
2361 	}
2362 
2363 	if (rdev->faulty) {
2364 		printk(KERN_WARNING
2365 			"md: can not hot-add faulty %s disk to %s!\n",
2366 			bdevname(rdev->bdev,b), mdname(mddev));
2367 		err = -EINVAL;
2368 		goto abort_export;
2369 	}
2370 	rdev->in_sync = 0;
2371 	rdev->desc_nr = -1;
2372 	bind_rdev_to_array(rdev, mddev);
2373 
2374 	/*
2375 	 * The rest should better be atomic, we can have disk failures
2376 	 * noticed in interrupt contexts ...
2377 	 */
2378 
2379 	if (rdev->desc_nr == mddev->max_disks) {
2380 		printk(KERN_WARNING "%s: can not hot-add to full array!\n",
2381 			mdname(mddev));
2382 		err = -EBUSY;
2383 		goto abort_unbind_export;
2384 	}
2385 
2386 	rdev->raid_disk = -1;
2387 
2388 	md_update_sb(mddev);
2389 
2390 	/*
2391 	 * Kick recovery, maybe this spare has to be added to the
2392 	 * array immediately.
2393 	 */
2394 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2395 	md_wakeup_thread(mddev->thread);
2396 
2397 	return 0;
2398 
2399 abort_unbind_export:
2400 	unbind_rdev_from_array(rdev);
2401 
2402 abort_export:
2403 	export_rdev(rdev);
2404 	return err;
2405 }
2406 
2407 /* similar to deny_write_access, but accounts for our holding a reference
2408  * to the file ourselves */
2409 static int deny_bitmap_write_access(struct file * file)
2410 {
2411 	struct inode *inode = file->f_mapping->host;
2412 
2413 	spin_lock(&inode->i_lock);
2414 	if (atomic_read(&inode->i_writecount) > 1) {
2415 		spin_unlock(&inode->i_lock);
2416 		return -ETXTBSY;
2417 	}
2418 	atomic_set(&inode->i_writecount, -1);
2419 	spin_unlock(&inode->i_lock);
2420 
2421 	return 0;
2422 }
2423 
2424 static int set_bitmap_file(mddev_t *mddev, int fd)
2425 {
2426 	int err;
2427 
2428 	if (mddev->pers)
2429 		return -EBUSY;
2430 
2431 	mddev->bitmap_file = fget(fd);
2432 
2433 	if (mddev->bitmap_file == NULL) {
2434 		printk(KERN_ERR "%s: error: failed to get bitmap file\n",
2435 			mdname(mddev));
2436 		return -EBADF;
2437 	}
2438 
2439 	err = deny_bitmap_write_access(mddev->bitmap_file);
2440 	if (err) {
2441 		printk(KERN_ERR "%s: error: bitmap file is already in use\n",
2442 			mdname(mddev));
2443 		fput(mddev->bitmap_file);
2444 		mddev->bitmap_file = NULL;
2445 	} else
2446 		mddev->bitmap_offset = 0; /* file overrides offset */
2447 	return err;
2448 }
2449 
2450 /*
2451  * set_array_info is used two different ways
2452  * The original usage is when creating a new array.
2453  * In this usage, raid_disks is > 0 and it together with
2454  *  level, size, not_persistent,layout,chunksize determine the
2455  *  shape of the array.
2456  *  This will always create an array with a type-0.90.0 superblock.
2457  * The newer usage is when assembling an array.
2458  *  In this case raid_disks will be 0, and the major_version field is
2459  *  use to determine which style super-blocks are to be found on the devices.
2460  *  The minor and patch _version numbers are also kept incase the
2461  *  super_block handler wishes to interpret them.
2462  */
2463 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
2464 {
2465 
2466 	if (info->raid_disks == 0) {
2467 		/* just setting version number for superblock loading */
2468 		if (info->major_version < 0 ||
2469 		    info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
2470 		    super_types[info->major_version].name == NULL) {
2471 			/* maybe try to auto-load a module? */
2472 			printk(KERN_INFO
2473 				"md: superblock version %d not known\n",
2474 				info->major_version);
2475 			return -EINVAL;
2476 		}
2477 		mddev->major_version = info->major_version;
2478 		mddev->minor_version = info->minor_version;
2479 		mddev->patch_version = info->patch_version;
2480 		return 0;
2481 	}
2482 	mddev->major_version = MD_MAJOR_VERSION;
2483 	mddev->minor_version = MD_MINOR_VERSION;
2484 	mddev->patch_version = MD_PATCHLEVEL_VERSION;
2485 	mddev->ctime         = get_seconds();
2486 
2487 	mddev->level         = info->level;
2488 	mddev->size          = info->size;
2489 	mddev->raid_disks    = info->raid_disks;
2490 	/* don't set md_minor, it is determined by which /dev/md* was
2491 	 * openned
2492 	 */
2493 	if (info->state & (1<<MD_SB_CLEAN))
2494 		mddev->recovery_cp = MaxSector;
2495 	else
2496 		mddev->recovery_cp = 0;
2497 	mddev->persistent    = ! info->not_persistent;
2498 
2499 	mddev->layout        = info->layout;
2500 	mddev->chunk_size    = info->chunk_size;
2501 
2502 	mddev->max_disks     = MD_SB_DISKS;
2503 
2504 	mddev->sb_dirty      = 1;
2505 
2506 	/*
2507 	 * Generate a 128 bit UUID
2508 	 */
2509 	get_random_bytes(mddev->uuid, 16);
2510 
2511 	return 0;
2512 }
2513 
2514 /*
2515  * update_array_info is used to change the configuration of an
2516  * on-line array.
2517  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
2518  * fields in the info are checked against the array.
2519  * Any differences that cannot be handled will cause an error.
2520  * Normally, only one change can be managed at a time.
2521  */
2522 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
2523 {
2524 	int rv = 0;
2525 	int cnt = 0;
2526 
2527 	if (mddev->major_version != info->major_version ||
2528 	    mddev->minor_version != info->minor_version ||
2529 /*	    mddev->patch_version != info->patch_version || */
2530 	    mddev->ctime         != info->ctime         ||
2531 	    mddev->level         != info->level         ||
2532 /*	    mddev->layout        != info->layout        || */
2533 	    !mddev->persistent	 != info->not_persistent||
2534 	    mddev->chunk_size    != info->chunk_size    )
2535 		return -EINVAL;
2536 	/* Check there is only one change */
2537 	if (mddev->size != info->size) cnt++;
2538 	if (mddev->raid_disks != info->raid_disks) cnt++;
2539 	if (mddev->layout != info->layout) cnt++;
2540 	if (cnt == 0) return 0;
2541 	if (cnt > 1) return -EINVAL;
2542 
2543 	if (mddev->layout != info->layout) {
2544 		/* Change layout
2545 		 * we don't need to do anything at the md level, the
2546 		 * personality will take care of it all.
2547 		 */
2548 		if (mddev->pers->reconfig == NULL)
2549 			return -EINVAL;
2550 		else
2551 			return mddev->pers->reconfig(mddev, info->layout, -1);
2552 	}
2553 	if (mddev->size != info->size) {
2554 		mdk_rdev_t * rdev;
2555 		struct list_head *tmp;
2556 		if (mddev->pers->resize == NULL)
2557 			return -EINVAL;
2558 		/* The "size" is the amount of each device that is used.
2559 		 * This can only make sense for arrays with redundancy.
2560 		 * linear and raid0 always use whatever space is available
2561 		 * We can only consider changing the size if no resync
2562 		 * or reconstruction is happening, and if the new size
2563 		 * is acceptable. It must fit before the sb_offset or,
2564 		 * if that is <data_offset, it must fit before the
2565 		 * size of each device.
2566 		 * If size is zero, we find the largest size that fits.
2567 		 */
2568 		if (mddev->sync_thread)
2569 			return -EBUSY;
2570 		ITERATE_RDEV(mddev,rdev,tmp) {
2571 			sector_t avail;
2572 			int fit = (info->size == 0);
2573 			if (rdev->sb_offset > rdev->data_offset)
2574 				avail = (rdev->sb_offset*2) - rdev->data_offset;
2575 			else
2576 				avail = get_capacity(rdev->bdev->bd_disk)
2577 					- rdev->data_offset;
2578 			if (fit && (info->size == 0 || info->size > avail/2))
2579 				info->size = avail/2;
2580 			if (avail < ((sector_t)info->size << 1))
2581 				return -ENOSPC;
2582 		}
2583 		rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
2584 		if (!rv) {
2585 			struct block_device *bdev;
2586 
2587 			bdev = bdget_disk(mddev->gendisk, 0);
2588 			if (bdev) {
2589 				down(&bdev->bd_inode->i_sem);
2590 				i_size_write(bdev->bd_inode, mddev->array_size << 10);
2591 				up(&bdev->bd_inode->i_sem);
2592 				bdput(bdev);
2593 			}
2594 		}
2595 	}
2596 	if (mddev->raid_disks    != info->raid_disks) {
2597 		/* change the number of raid disks */
2598 		if (mddev->pers->reshape == NULL)
2599 			return -EINVAL;
2600 		if (info->raid_disks <= 0 ||
2601 		    info->raid_disks >= mddev->max_disks)
2602 			return -EINVAL;
2603 		if (mddev->sync_thread)
2604 			return -EBUSY;
2605 		rv = mddev->pers->reshape(mddev, info->raid_disks);
2606 		if (!rv) {
2607 			struct block_device *bdev;
2608 
2609 			bdev = bdget_disk(mddev->gendisk, 0);
2610 			if (bdev) {
2611 				down(&bdev->bd_inode->i_sem);
2612 				i_size_write(bdev->bd_inode, mddev->array_size << 10);
2613 				up(&bdev->bd_inode->i_sem);
2614 				bdput(bdev);
2615 			}
2616 		}
2617 	}
2618 	md_update_sb(mddev);
2619 	return rv;
2620 }
2621 
2622 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
2623 {
2624 	mdk_rdev_t *rdev;
2625 
2626 	if (mddev->pers == NULL)
2627 		return -ENODEV;
2628 
2629 	rdev = find_rdev(mddev, dev);
2630 	if (!rdev)
2631 		return -ENODEV;
2632 
2633 	md_error(mddev, rdev);
2634 	return 0;
2635 }
2636 
2637 static int md_ioctl(struct inode *inode, struct file *file,
2638 			unsigned int cmd, unsigned long arg)
2639 {
2640 	int err = 0;
2641 	void __user *argp = (void __user *)arg;
2642 	struct hd_geometry __user *loc = argp;
2643 	mddev_t *mddev = NULL;
2644 
2645 	if (!capable(CAP_SYS_ADMIN))
2646 		return -EACCES;
2647 
2648 	/*
2649 	 * Commands dealing with the RAID driver but not any
2650 	 * particular array:
2651 	 */
2652 	switch (cmd)
2653 	{
2654 		case RAID_VERSION:
2655 			err = get_version(argp);
2656 			goto done;
2657 
2658 		case PRINT_RAID_DEBUG:
2659 			err = 0;
2660 			md_print_devices();
2661 			goto done;
2662 
2663 #ifndef MODULE
2664 		case RAID_AUTORUN:
2665 			err = 0;
2666 			autostart_arrays(arg);
2667 			goto done;
2668 #endif
2669 		default:;
2670 	}
2671 
2672 	/*
2673 	 * Commands creating/starting a new array:
2674 	 */
2675 
2676 	mddev = inode->i_bdev->bd_disk->private_data;
2677 
2678 	if (!mddev) {
2679 		BUG();
2680 		goto abort;
2681 	}
2682 
2683 
2684 	if (cmd == START_ARRAY) {
2685 		/* START_ARRAY doesn't need to lock the array as autostart_array
2686 		 * does the locking, and it could even be a different array
2687 		 */
2688 		static int cnt = 3;
2689 		if (cnt > 0 ) {
2690 			printk(KERN_WARNING
2691 			       "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
2692 			       "This will not be supported beyond 2.6\n",
2693 			       current->comm, current->pid);
2694 			cnt--;
2695 		}
2696 		err = autostart_array(new_decode_dev(arg));
2697 		if (err) {
2698 			printk(KERN_WARNING "md: autostart failed!\n");
2699 			goto abort;
2700 		}
2701 		goto done;
2702 	}
2703 
2704 	err = mddev_lock(mddev);
2705 	if (err) {
2706 		printk(KERN_INFO
2707 			"md: ioctl lock interrupted, reason %d, cmd %d\n",
2708 			err, cmd);
2709 		goto abort;
2710 	}
2711 
2712 	switch (cmd)
2713 	{
2714 		case SET_ARRAY_INFO:
2715 			{
2716 				mdu_array_info_t info;
2717 				if (!arg)
2718 					memset(&info, 0, sizeof(info));
2719 				else if (copy_from_user(&info, argp, sizeof(info))) {
2720 					err = -EFAULT;
2721 					goto abort_unlock;
2722 				}
2723 				if (mddev->pers) {
2724 					err = update_array_info(mddev, &info);
2725 					if (err) {
2726 						printk(KERN_WARNING "md: couldn't update"
2727 						       " array info. %d\n", err);
2728 						goto abort_unlock;
2729 					}
2730 					goto done_unlock;
2731 				}
2732 				if (!list_empty(&mddev->disks)) {
2733 					printk(KERN_WARNING
2734 					       "md: array %s already has disks!\n",
2735 					       mdname(mddev));
2736 					err = -EBUSY;
2737 					goto abort_unlock;
2738 				}
2739 				if (mddev->raid_disks) {
2740 					printk(KERN_WARNING
2741 					       "md: array %s already initialised!\n",
2742 					       mdname(mddev));
2743 					err = -EBUSY;
2744 					goto abort_unlock;
2745 				}
2746 				err = set_array_info(mddev, &info);
2747 				if (err) {
2748 					printk(KERN_WARNING "md: couldn't set"
2749 					       " array info. %d\n", err);
2750 					goto abort_unlock;
2751 				}
2752 			}
2753 			goto done_unlock;
2754 
2755 		default:;
2756 	}
2757 
2758 	/*
2759 	 * Commands querying/configuring an existing array:
2760 	 */
2761 	/* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
2762 	 * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
2763 	if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
2764 			&& cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
2765 		err = -ENODEV;
2766 		goto abort_unlock;
2767 	}
2768 
2769 	/*
2770 	 * Commands even a read-only array can execute:
2771 	 */
2772 	switch (cmd)
2773 	{
2774 		case GET_ARRAY_INFO:
2775 			err = get_array_info(mddev, argp);
2776 			goto done_unlock;
2777 
2778 		case GET_BITMAP_FILE:
2779 			err = get_bitmap_file(mddev, (void *)arg);
2780 			goto done_unlock;
2781 
2782 		case GET_DISK_INFO:
2783 			err = get_disk_info(mddev, argp);
2784 			goto done_unlock;
2785 
2786 		case RESTART_ARRAY_RW:
2787 			err = restart_array(mddev);
2788 			goto done_unlock;
2789 
2790 		case STOP_ARRAY:
2791 			err = do_md_stop (mddev, 0);
2792 			goto done_unlock;
2793 
2794 		case STOP_ARRAY_RO:
2795 			err = do_md_stop (mddev, 1);
2796 			goto done_unlock;
2797 
2798 	/*
2799 	 * We have a problem here : there is no easy way to give a CHS
2800 	 * virtual geometry. We currently pretend that we have a 2 heads
2801 	 * 4 sectors (with a BIG number of cylinders...). This drives
2802 	 * dosfs just mad... ;-)
2803 	 */
2804 		case HDIO_GETGEO:
2805 			if (!loc) {
2806 				err = -EINVAL;
2807 				goto abort_unlock;
2808 			}
2809 			err = put_user (2, (char __user *) &loc->heads);
2810 			if (err)
2811 				goto abort_unlock;
2812 			err = put_user (4, (char __user *) &loc->sectors);
2813 			if (err)
2814 				goto abort_unlock;
2815 			err = put_user(get_capacity(mddev->gendisk)/8,
2816 					(short __user *) &loc->cylinders);
2817 			if (err)
2818 				goto abort_unlock;
2819 			err = put_user (get_start_sect(inode->i_bdev),
2820 						(long __user *) &loc->start);
2821 			goto done_unlock;
2822 	}
2823 
2824 	/*
2825 	 * The remaining ioctls are changing the state of the
2826 	 * superblock, so we do not allow read-only arrays
2827 	 * here:
2828 	 */
2829 	if (mddev->ro) {
2830 		err = -EROFS;
2831 		goto abort_unlock;
2832 	}
2833 
2834 	switch (cmd)
2835 	{
2836 		case ADD_NEW_DISK:
2837 		{
2838 			mdu_disk_info_t info;
2839 			if (copy_from_user(&info, argp, sizeof(info)))
2840 				err = -EFAULT;
2841 			else
2842 				err = add_new_disk(mddev, &info);
2843 			goto done_unlock;
2844 		}
2845 
2846 		case HOT_REMOVE_DISK:
2847 			err = hot_remove_disk(mddev, new_decode_dev(arg));
2848 			goto done_unlock;
2849 
2850 		case HOT_ADD_DISK:
2851 			err = hot_add_disk(mddev, new_decode_dev(arg));
2852 			goto done_unlock;
2853 
2854 		case SET_DISK_FAULTY:
2855 			err = set_disk_faulty(mddev, new_decode_dev(arg));
2856 			goto done_unlock;
2857 
2858 		case RUN_ARRAY:
2859 			err = do_md_run (mddev);
2860 			goto done_unlock;
2861 
2862 		case SET_BITMAP_FILE:
2863 			err = set_bitmap_file(mddev, (int)arg);
2864 			goto done_unlock;
2865 
2866 		default:
2867 			if (_IOC_TYPE(cmd) == MD_MAJOR)
2868 				printk(KERN_WARNING "md: %s(pid %d) used"
2869 					" obsolete MD ioctl, upgrade your"
2870 					" software to use new ictls.\n",
2871 					current->comm, current->pid);
2872 			err = -EINVAL;
2873 			goto abort_unlock;
2874 	}
2875 
2876 done_unlock:
2877 abort_unlock:
2878 	mddev_unlock(mddev);
2879 
2880 	return err;
2881 done:
2882 	if (err)
2883 		MD_BUG();
2884 abort:
2885 	return err;
2886 }
2887 
2888 static int md_open(struct inode *inode, struct file *file)
2889 {
2890 	/*
2891 	 * Succeed if we can lock the mddev, which confirms that
2892 	 * it isn't being stopped right now.
2893 	 */
2894 	mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2895 	int err;
2896 
2897 	if ((err = mddev_lock(mddev)))
2898 		goto out;
2899 
2900 	err = 0;
2901 	mddev_get(mddev);
2902 	mddev_unlock(mddev);
2903 
2904 	check_disk_change(inode->i_bdev);
2905  out:
2906 	return err;
2907 }
2908 
2909 static int md_release(struct inode *inode, struct file * file)
2910 {
2911  	mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
2912 
2913 	if (!mddev)
2914 		BUG();
2915 	mddev_put(mddev);
2916 
2917 	return 0;
2918 }
2919 
2920 static int md_media_changed(struct gendisk *disk)
2921 {
2922 	mddev_t *mddev = disk->private_data;
2923 
2924 	return mddev->changed;
2925 }
2926 
2927 static int md_revalidate(struct gendisk *disk)
2928 {
2929 	mddev_t *mddev = disk->private_data;
2930 
2931 	mddev->changed = 0;
2932 	return 0;
2933 }
2934 static struct block_device_operations md_fops =
2935 {
2936 	.owner		= THIS_MODULE,
2937 	.open		= md_open,
2938 	.release	= md_release,
2939 	.ioctl		= md_ioctl,
2940 	.media_changed	= md_media_changed,
2941 	.revalidate_disk= md_revalidate,
2942 };
2943 
2944 static int md_thread(void * arg)
2945 {
2946 	mdk_thread_t *thread = arg;
2947 
2948 	lock_kernel();
2949 
2950 	/*
2951 	 * Detach thread
2952 	 */
2953 
2954 	daemonize(thread->name, mdname(thread->mddev));
2955 
2956 	current->exit_signal = SIGCHLD;
2957 	allow_signal(SIGKILL);
2958 	thread->tsk = current;
2959 
2960 	/*
2961 	 * md_thread is a 'system-thread', it's priority should be very
2962 	 * high. We avoid resource deadlocks individually in each
2963 	 * raid personality. (RAID5 does preallocation) We also use RR and
2964 	 * the very same RT priority as kswapd, thus we will never get
2965 	 * into a priority inversion deadlock.
2966 	 *
2967 	 * we definitely have to have equal or higher priority than
2968 	 * bdflush, otherwise bdflush will deadlock if there are too
2969 	 * many dirty RAID5 blocks.
2970 	 */
2971 	unlock_kernel();
2972 
2973 	complete(thread->event);
2974 	while (thread->run) {
2975 		void (*run)(mddev_t *);
2976 
2977 		wait_event_interruptible_timeout(thread->wqueue,
2978 						 test_bit(THREAD_WAKEUP, &thread->flags),
2979 						 thread->timeout);
2980 		try_to_freeze();
2981 
2982 		clear_bit(THREAD_WAKEUP, &thread->flags);
2983 
2984 		run = thread->run;
2985 		if (run)
2986 			run(thread->mddev);
2987 
2988 		if (signal_pending(current))
2989 			flush_signals(current);
2990 	}
2991 	complete(thread->event);
2992 	return 0;
2993 }
2994 
2995 void md_wakeup_thread(mdk_thread_t *thread)
2996 {
2997 	if (thread) {
2998 		dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
2999 		set_bit(THREAD_WAKEUP, &thread->flags);
3000 		wake_up(&thread->wqueue);
3001 	}
3002 }
3003 
3004 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
3005 				 const char *name)
3006 {
3007 	mdk_thread_t *thread;
3008 	int ret;
3009 	struct completion event;
3010 
3011 	thread = (mdk_thread_t *) kmalloc
3012 				(sizeof(mdk_thread_t), GFP_KERNEL);
3013 	if (!thread)
3014 		return NULL;
3015 
3016 	memset(thread, 0, sizeof(mdk_thread_t));
3017 	init_waitqueue_head(&thread->wqueue);
3018 
3019 	init_completion(&event);
3020 	thread->event = &event;
3021 	thread->run = run;
3022 	thread->mddev = mddev;
3023 	thread->name = name;
3024 	thread->timeout = MAX_SCHEDULE_TIMEOUT;
3025 	ret = kernel_thread(md_thread, thread, 0);
3026 	if (ret < 0) {
3027 		kfree(thread);
3028 		return NULL;
3029 	}
3030 	wait_for_completion(&event);
3031 	return thread;
3032 }
3033 
3034 void md_unregister_thread(mdk_thread_t *thread)
3035 {
3036 	struct completion event;
3037 
3038 	init_completion(&event);
3039 
3040 	thread->event = &event;
3041 
3042 	/* As soon as ->run is set to NULL, the task could disappear,
3043 	 * so we need to hold tasklist_lock until we have sent the signal
3044 	 */
3045 	dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
3046 	read_lock(&tasklist_lock);
3047 	thread->run = NULL;
3048 	send_sig(SIGKILL, thread->tsk, 1);
3049 	read_unlock(&tasklist_lock);
3050 	wait_for_completion(&event);
3051 	kfree(thread);
3052 }
3053 
3054 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
3055 {
3056 	if (!mddev) {
3057 		MD_BUG();
3058 		return;
3059 	}
3060 
3061 	if (!rdev || rdev->faulty)
3062 		return;
3063 /*
3064 	dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
3065 		mdname(mddev),
3066 		MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
3067 		__builtin_return_address(0),__builtin_return_address(1),
3068 		__builtin_return_address(2),__builtin_return_address(3));
3069 */
3070 	if (!mddev->pers->error_handler)
3071 		return;
3072 	mddev->pers->error_handler(mddev,rdev);
3073 	set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3074 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3075 	md_wakeup_thread(mddev->thread);
3076 }
3077 
3078 /* seq_file implementation /proc/mdstat */
3079 
3080 static void status_unused(struct seq_file *seq)
3081 {
3082 	int i = 0;
3083 	mdk_rdev_t *rdev;
3084 	struct list_head *tmp;
3085 
3086 	seq_printf(seq, "unused devices: ");
3087 
3088 	ITERATE_RDEV_PENDING(rdev,tmp) {
3089 		char b[BDEVNAME_SIZE];
3090 		i++;
3091 		seq_printf(seq, "%s ",
3092 			      bdevname(rdev->bdev,b));
3093 	}
3094 	if (!i)
3095 		seq_printf(seq, "<none>");
3096 
3097 	seq_printf(seq, "\n");
3098 }
3099 
3100 
3101 static void status_resync(struct seq_file *seq, mddev_t * mddev)
3102 {
3103 	unsigned long max_blocks, resync, res, dt, db, rt;
3104 
3105 	resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
3106 
3107 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3108 		max_blocks = mddev->resync_max_sectors >> 1;
3109 	else
3110 		max_blocks = mddev->size;
3111 
3112 	/*
3113 	 * Should not happen.
3114 	 */
3115 	if (!max_blocks) {
3116 		MD_BUG();
3117 		return;
3118 	}
3119 	res = (resync/1024)*1000/(max_blocks/1024 + 1);
3120 	{
3121 		int i, x = res/50, y = 20-x;
3122 		seq_printf(seq, "[");
3123 		for (i = 0; i < x; i++)
3124 			seq_printf(seq, "=");
3125 		seq_printf(seq, ">");
3126 		for (i = 0; i < y; i++)
3127 			seq_printf(seq, ".");
3128 		seq_printf(seq, "] ");
3129 	}
3130 	seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
3131 		      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
3132 		       "resync" : "recovery"),
3133 		      res/10, res % 10, resync, max_blocks);
3134 
3135 	/*
3136 	 * We do not want to overflow, so the order of operands and
3137 	 * the * 100 / 100 trick are important. We do a +1 to be
3138 	 * safe against division by zero. We only estimate anyway.
3139 	 *
3140 	 * dt: time from mark until now
3141 	 * db: blocks written from mark until now
3142 	 * rt: remaining time
3143 	 */
3144 	dt = ((jiffies - mddev->resync_mark) / HZ);
3145 	if (!dt) dt++;
3146 	db = resync - (mddev->resync_mark_cnt/2);
3147 	rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
3148 
3149 	seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
3150 
3151 	seq_printf(seq, " speed=%ldK/sec", db/dt);
3152 }
3153 
3154 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
3155 {
3156 	struct list_head *tmp;
3157 	loff_t l = *pos;
3158 	mddev_t *mddev;
3159 
3160 	if (l >= 0x10000)
3161 		return NULL;
3162 	if (!l--)
3163 		/* header */
3164 		return (void*)1;
3165 
3166 	spin_lock(&all_mddevs_lock);
3167 	list_for_each(tmp,&all_mddevs)
3168 		if (!l--) {
3169 			mddev = list_entry(tmp, mddev_t, all_mddevs);
3170 			mddev_get(mddev);
3171 			spin_unlock(&all_mddevs_lock);
3172 			return mddev;
3173 		}
3174 	spin_unlock(&all_mddevs_lock);
3175 	if (!l--)
3176 		return (void*)2;/* tail */
3177 	return NULL;
3178 }
3179 
3180 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3181 {
3182 	struct list_head *tmp;
3183 	mddev_t *next_mddev, *mddev = v;
3184 
3185 	++*pos;
3186 	if (v == (void*)2)
3187 		return NULL;
3188 
3189 	spin_lock(&all_mddevs_lock);
3190 	if (v == (void*)1)
3191 		tmp = all_mddevs.next;
3192 	else
3193 		tmp = mddev->all_mddevs.next;
3194 	if (tmp != &all_mddevs)
3195 		next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
3196 	else {
3197 		next_mddev = (void*)2;
3198 		*pos = 0x10000;
3199 	}
3200 	spin_unlock(&all_mddevs_lock);
3201 
3202 	if (v != (void*)1)
3203 		mddev_put(mddev);
3204 	return next_mddev;
3205 
3206 }
3207 
3208 static void md_seq_stop(struct seq_file *seq, void *v)
3209 {
3210 	mddev_t *mddev = v;
3211 
3212 	if (mddev && v != (void*)1 && v != (void*)2)
3213 		mddev_put(mddev);
3214 }
3215 
3216 static int md_seq_show(struct seq_file *seq, void *v)
3217 {
3218 	mddev_t *mddev = v;
3219 	sector_t size;
3220 	struct list_head *tmp2;
3221 	mdk_rdev_t *rdev;
3222 	int i;
3223 	struct bitmap *bitmap;
3224 
3225 	if (v == (void*)1) {
3226 		seq_printf(seq, "Personalities : ");
3227 		spin_lock(&pers_lock);
3228 		for (i = 0; i < MAX_PERSONALITY; i++)
3229 			if (pers[i])
3230 				seq_printf(seq, "[%s] ", pers[i]->name);
3231 
3232 		spin_unlock(&pers_lock);
3233 		seq_printf(seq, "\n");
3234 		return 0;
3235 	}
3236 	if (v == (void*)2) {
3237 		status_unused(seq);
3238 		return 0;
3239 	}
3240 
3241 	if (mddev_lock(mddev)!=0)
3242 		return -EINTR;
3243 	if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
3244 		seq_printf(seq, "%s : %sactive", mdname(mddev),
3245 						mddev->pers ? "" : "in");
3246 		if (mddev->pers) {
3247 			if (mddev->ro)
3248 				seq_printf(seq, " (read-only)");
3249 			seq_printf(seq, " %s", mddev->pers->name);
3250 		}
3251 
3252 		size = 0;
3253 		ITERATE_RDEV(mddev,rdev,tmp2) {
3254 			char b[BDEVNAME_SIZE];
3255 			seq_printf(seq, " %s[%d]",
3256 				bdevname(rdev->bdev,b), rdev->desc_nr);
3257 			if (rdev->faulty) {
3258 				seq_printf(seq, "(F)");
3259 				continue;
3260 			}
3261 			size += rdev->size;
3262 		}
3263 
3264 		if (!list_empty(&mddev->disks)) {
3265 			if (mddev->pers)
3266 				seq_printf(seq, "\n      %llu blocks",
3267 					(unsigned long long)mddev->array_size);
3268 			else
3269 				seq_printf(seq, "\n      %llu blocks",
3270 					(unsigned long long)size);
3271 		}
3272 
3273 		if (mddev->pers) {
3274 			mddev->pers->status (seq, mddev);
3275 	 		seq_printf(seq, "\n      ");
3276 			if (mddev->curr_resync > 2) {
3277 				status_resync (seq, mddev);
3278 				seq_printf(seq, "\n      ");
3279 			} else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
3280 				seq_printf(seq, "	resync=DELAYED\n      ");
3281 		} else
3282 			seq_printf(seq, "\n       ");
3283 
3284 		if ((bitmap = mddev->bitmap)) {
3285 			unsigned long chunk_kb;
3286 			unsigned long flags;
3287 			spin_lock_irqsave(&bitmap->lock, flags);
3288 			chunk_kb = bitmap->chunksize >> 10;
3289 			seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
3290 				"%lu%s chunk",
3291 				bitmap->pages - bitmap->missing_pages,
3292 				bitmap->pages,
3293 				(bitmap->pages - bitmap->missing_pages)
3294 					<< (PAGE_SHIFT - 10),
3295 				chunk_kb ? chunk_kb : bitmap->chunksize,
3296 				chunk_kb ? "KB" : "B");
3297 			if (bitmap->file) {
3298 				seq_printf(seq, ", file: ");
3299 				seq_path(seq, bitmap->file->f_vfsmnt,
3300 					 bitmap->file->f_dentry," \t\n");
3301 			}
3302 
3303 			seq_printf(seq, "\n");
3304 			spin_unlock_irqrestore(&bitmap->lock, flags);
3305 		}
3306 
3307 		seq_printf(seq, "\n");
3308 	}
3309 	mddev_unlock(mddev);
3310 
3311 	return 0;
3312 }
3313 
3314 static struct seq_operations md_seq_ops = {
3315 	.start  = md_seq_start,
3316 	.next   = md_seq_next,
3317 	.stop   = md_seq_stop,
3318 	.show   = md_seq_show,
3319 };
3320 
3321 static int md_seq_open(struct inode *inode, struct file *file)
3322 {
3323 	int error;
3324 
3325 	error = seq_open(file, &md_seq_ops);
3326 	return error;
3327 }
3328 
3329 static struct file_operations md_seq_fops = {
3330 	.open           = md_seq_open,
3331 	.read           = seq_read,
3332 	.llseek         = seq_lseek,
3333 	.release	= seq_release,
3334 };
3335 
3336 int register_md_personality(int pnum, mdk_personality_t *p)
3337 {
3338 	if (pnum >= MAX_PERSONALITY) {
3339 		printk(KERN_ERR
3340 		       "md: tried to install personality %s as nr %d, but max is %lu\n",
3341 		       p->name, pnum, MAX_PERSONALITY-1);
3342 		return -EINVAL;
3343 	}
3344 
3345 	spin_lock(&pers_lock);
3346 	if (pers[pnum]) {
3347 		spin_unlock(&pers_lock);
3348 		return -EBUSY;
3349 	}
3350 
3351 	pers[pnum] = p;
3352 	printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
3353 	spin_unlock(&pers_lock);
3354 	return 0;
3355 }
3356 
3357 int unregister_md_personality(int pnum)
3358 {
3359 	if (pnum >= MAX_PERSONALITY)
3360 		return -EINVAL;
3361 
3362 	printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
3363 	spin_lock(&pers_lock);
3364 	pers[pnum] = NULL;
3365 	spin_unlock(&pers_lock);
3366 	return 0;
3367 }
3368 
3369 static int is_mddev_idle(mddev_t *mddev)
3370 {
3371 	mdk_rdev_t * rdev;
3372 	struct list_head *tmp;
3373 	int idle;
3374 	unsigned long curr_events;
3375 
3376 	idle = 1;
3377 	ITERATE_RDEV(mddev,rdev,tmp) {
3378 		struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
3379 		curr_events = disk_stat_read(disk, read_sectors) +
3380 				disk_stat_read(disk, write_sectors) -
3381 				atomic_read(&disk->sync_io);
3382 		/* Allow some slack between valud of curr_events and last_events,
3383 		 * as there are some uninteresting races.
3384 		 * Note: the following is an unsigned comparison.
3385 		 */
3386 		if ((curr_events - rdev->last_events + 32) > 64) {
3387 			rdev->last_events = curr_events;
3388 			idle = 0;
3389 		}
3390 	}
3391 	return idle;
3392 }
3393 
3394 void md_done_sync(mddev_t *mddev, int blocks, int ok)
3395 {
3396 	/* another "blocks" (512byte) blocks have been synced */
3397 	atomic_sub(blocks, &mddev->recovery_active);
3398 	wake_up(&mddev->recovery_wait);
3399 	if (!ok) {
3400 		set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3401 		md_wakeup_thread(mddev->thread);
3402 		// stop recovery, signal do_sync ....
3403 	}
3404 }
3405 
3406 
3407 /* md_write_start(mddev, bi)
3408  * If we need to update some array metadata (e.g. 'active' flag
3409  * in superblock) before writing, schedule a superblock update
3410  * and wait for it to complete.
3411  */
3412 void md_write_start(mddev_t *mddev, struct bio *bi)
3413 {
3414 	DEFINE_WAIT(w);
3415 	if (bio_data_dir(bi) != WRITE)
3416 		return;
3417 
3418 	atomic_inc(&mddev->writes_pending);
3419 	if (mddev->in_sync) {
3420 		spin_lock(&mddev->write_lock);
3421 		if (mddev->in_sync) {
3422 			mddev->in_sync = 0;
3423 			mddev->sb_dirty = 1;
3424 			md_wakeup_thread(mddev->thread);
3425 		}
3426 		spin_unlock(&mddev->write_lock);
3427 	}
3428 	wait_event(mddev->sb_wait, mddev->sb_dirty==0);
3429 }
3430 
3431 void md_write_end(mddev_t *mddev)
3432 {
3433 	if (atomic_dec_and_test(&mddev->writes_pending)) {
3434 		if (mddev->safemode == 2)
3435 			md_wakeup_thread(mddev->thread);
3436 		else
3437 			mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
3438 	}
3439 }
3440 
3441 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
3442 
3443 #define SYNC_MARKS	10
3444 #define	SYNC_MARK_STEP	(3*HZ)
3445 static void md_do_sync(mddev_t *mddev)
3446 {
3447 	mddev_t *mddev2;
3448 	unsigned int currspeed = 0,
3449 		 window;
3450 	sector_t max_sectors,j, io_sectors;
3451 	unsigned long mark[SYNC_MARKS];
3452 	sector_t mark_cnt[SYNC_MARKS];
3453 	int last_mark,m;
3454 	struct list_head *tmp;
3455 	sector_t last_check;
3456 	int skipped = 0;
3457 
3458 	/* just incase thread restarts... */
3459 	if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
3460 		return;
3461 
3462 	/* we overload curr_resync somewhat here.
3463 	 * 0 == not engaged in resync at all
3464 	 * 2 == checking that there is no conflict with another sync
3465 	 * 1 == like 2, but have yielded to allow conflicting resync to
3466 	 *		commense
3467 	 * other == active in resync - this many blocks
3468 	 *
3469 	 * Before starting a resync we must have set curr_resync to
3470 	 * 2, and then checked that every "conflicting" array has curr_resync
3471 	 * less than ours.  When we find one that is the same or higher
3472 	 * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
3473 	 * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
3474 	 * This will mean we have to start checking from the beginning again.
3475 	 *
3476 	 */
3477 
3478 	do {
3479 		mddev->curr_resync = 2;
3480 
3481 	try_again:
3482 		if (signal_pending(current)) {
3483 			flush_signals(current);
3484 			goto skip;
3485 		}
3486 		ITERATE_MDDEV(mddev2,tmp) {
3487 			printk(".");
3488 			if (mddev2 == mddev)
3489 				continue;
3490 			if (mddev2->curr_resync &&
3491 			    match_mddev_units(mddev,mddev2)) {
3492 				DEFINE_WAIT(wq);
3493 				if (mddev < mddev2 && mddev->curr_resync == 2) {
3494 					/* arbitrarily yield */
3495 					mddev->curr_resync = 1;
3496 					wake_up(&resync_wait);
3497 				}
3498 				if (mddev > mddev2 && mddev->curr_resync == 1)
3499 					/* no need to wait here, we can wait the next
3500 					 * time 'round when curr_resync == 2
3501 					 */
3502 					continue;
3503 				prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
3504 				if (!signal_pending(current)
3505 				    && mddev2->curr_resync >= mddev->curr_resync) {
3506 					printk(KERN_INFO "md: delaying resync of %s"
3507 					       " until %s has finished resync (they"
3508 					       " share one or more physical units)\n",
3509 					       mdname(mddev), mdname(mddev2));
3510 					mddev_put(mddev2);
3511 					schedule();
3512 					finish_wait(&resync_wait, &wq);
3513 					goto try_again;
3514 				}
3515 				finish_wait(&resync_wait, &wq);
3516 			}
3517 		}
3518 	} while (mddev->curr_resync < 2);
3519 
3520 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3521 		/* resync follows the size requested by the personality,
3522 		 * which defaults to physical size, but can be virtual size
3523 		 */
3524 		max_sectors = mddev->resync_max_sectors;
3525 	else
3526 		/* recovery follows the physical size of devices */
3527 		max_sectors = mddev->size << 1;
3528 
3529 	printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
3530 	printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
3531 		" %d KB/sec/disc.\n", sysctl_speed_limit_min);
3532 	printk(KERN_INFO "md: using maximum available idle IO bandwith "
3533 	       "(but not more than %d KB/sec) for reconstruction.\n",
3534 	       sysctl_speed_limit_max);
3535 
3536 	is_mddev_idle(mddev); /* this also initializes IO event counters */
3537 	/* we don't use the checkpoint if there's a bitmap */
3538 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)
3539 		j = mddev->recovery_cp;
3540 	else
3541 		j = 0;
3542 	io_sectors = 0;
3543 	for (m = 0; m < SYNC_MARKS; m++) {
3544 		mark[m] = jiffies;
3545 		mark_cnt[m] = io_sectors;
3546 	}
3547 	last_mark = 0;
3548 	mddev->resync_mark = mark[last_mark];
3549 	mddev->resync_mark_cnt = mark_cnt[last_mark];
3550 
3551 	/*
3552 	 * Tune reconstruction:
3553 	 */
3554 	window = 32*(PAGE_SIZE/512);
3555 	printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
3556 		window/2,(unsigned long long) max_sectors/2);
3557 
3558 	atomic_set(&mddev->recovery_active, 0);
3559 	init_waitqueue_head(&mddev->recovery_wait);
3560 	last_check = 0;
3561 
3562 	if (j>2) {
3563 		printk(KERN_INFO
3564 			"md: resuming recovery of %s from checkpoint.\n",
3565 			mdname(mddev));
3566 		mddev->curr_resync = j;
3567 	}
3568 
3569 	while (j < max_sectors) {
3570 		sector_t sectors;
3571 
3572 		skipped = 0;
3573 		sectors = mddev->pers->sync_request(mddev, j, &skipped,
3574 					    currspeed < sysctl_speed_limit_min);
3575 		if (sectors == 0) {
3576 			set_bit(MD_RECOVERY_ERR, &mddev->recovery);
3577 			goto out;
3578 		}
3579 
3580 		if (!skipped) { /* actual IO requested */
3581 			io_sectors += sectors;
3582 			atomic_add(sectors, &mddev->recovery_active);
3583 		}
3584 
3585 		j += sectors;
3586 		if (j>1) mddev->curr_resync = j;
3587 
3588 
3589 		if (last_check + window > io_sectors || j == max_sectors)
3590 			continue;
3591 
3592 		last_check = io_sectors;
3593 
3594 		if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
3595 		    test_bit(MD_RECOVERY_ERR, &mddev->recovery))
3596 			break;
3597 
3598 	repeat:
3599 		if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
3600 			/* step marks */
3601 			int next = (last_mark+1) % SYNC_MARKS;
3602 
3603 			mddev->resync_mark = mark[next];
3604 			mddev->resync_mark_cnt = mark_cnt[next];
3605 			mark[next] = jiffies;
3606 			mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
3607 			last_mark = next;
3608 		}
3609 
3610 
3611 		if (signal_pending(current)) {
3612 			/*
3613 			 * got a signal, exit.
3614 			 */
3615 			printk(KERN_INFO
3616 				"md: md_do_sync() got signal ... exiting\n");
3617 			flush_signals(current);
3618 			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3619 			goto out;
3620 		}
3621 
3622 		/*
3623 		 * this loop exits only if either when we are slower than
3624 		 * the 'hard' speed limit, or the system was IO-idle for
3625 		 * a jiffy.
3626 		 * the system might be non-idle CPU-wise, but we only care
3627 		 * about not overloading the IO subsystem. (things like an
3628 		 * e2fsck being done on the RAID array should execute fast)
3629 		 */
3630 		mddev->queue->unplug_fn(mddev->queue);
3631 		cond_resched();
3632 
3633 		currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
3634 			/((jiffies-mddev->resync_mark)/HZ +1) +1;
3635 
3636 		if (currspeed > sysctl_speed_limit_min) {
3637 			if ((currspeed > sysctl_speed_limit_max) ||
3638 					!is_mddev_idle(mddev)) {
3639 				msleep_interruptible(250);
3640 				goto repeat;
3641 			}
3642 		}
3643 	}
3644 	printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
3645 	/*
3646 	 * this also signals 'finished resyncing' to md_stop
3647 	 */
3648  out:
3649 	mddev->queue->unplug_fn(mddev->queue);
3650 
3651 	wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
3652 
3653 	/* tell personality that we are finished */
3654 	mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
3655 
3656 	if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3657 	    mddev->curr_resync > 2 &&
3658 	    mddev->curr_resync >= mddev->recovery_cp) {
3659 		if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3660 			printk(KERN_INFO
3661 				"md: checkpointing recovery of %s.\n",
3662 				mdname(mddev));
3663 			mddev->recovery_cp = mddev->curr_resync;
3664 		} else
3665 			mddev->recovery_cp = MaxSector;
3666 	}
3667 
3668  skip:
3669 	mddev->curr_resync = 0;
3670 	wake_up(&resync_wait);
3671 	set_bit(MD_RECOVERY_DONE, &mddev->recovery);
3672 	md_wakeup_thread(mddev->thread);
3673 }
3674 
3675 
3676 /*
3677  * This routine is regularly called by all per-raid-array threads to
3678  * deal with generic issues like resync and super-block update.
3679  * Raid personalities that don't have a thread (linear/raid0) do not
3680  * need this as they never do any recovery or update the superblock.
3681  *
3682  * It does not do any resync itself, but rather "forks" off other threads
3683  * to do that as needed.
3684  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
3685  * "->recovery" and create a thread at ->sync_thread.
3686  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
3687  * and wakeups up this thread which will reap the thread and finish up.
3688  * This thread also removes any faulty devices (with nr_pending == 0).
3689  *
3690  * The overall approach is:
3691  *  1/ if the superblock needs updating, update it.
3692  *  2/ If a recovery thread is running, don't do anything else.
3693  *  3/ If recovery has finished, clean up, possibly marking spares active.
3694  *  4/ If there are any faulty devices, remove them.
3695  *  5/ If array is degraded, try to add spares devices
3696  *  6/ If array has spares or is not in-sync, start a resync thread.
3697  */
3698 void md_check_recovery(mddev_t *mddev)
3699 {
3700 	mdk_rdev_t *rdev;
3701 	struct list_head *rtmp;
3702 
3703 
3704 	if (mddev->bitmap)
3705 		bitmap_daemon_work(mddev->bitmap);
3706 
3707 	if (mddev->ro)
3708 		return;
3709 
3710 	if (signal_pending(current)) {
3711 		if (mddev->pers->sync_request) {
3712 			printk(KERN_INFO "md: %s in immediate safe mode\n",
3713 			       mdname(mddev));
3714 			mddev->safemode = 2;
3715 		}
3716 		flush_signals(current);
3717 	}
3718 
3719 	if ( ! (
3720 		mddev->sb_dirty ||
3721 		test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
3722 		test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
3723 		(mddev->safemode == 1) ||
3724 		(mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
3725 		 && !mddev->in_sync && mddev->recovery_cp == MaxSector)
3726 		))
3727 		return;
3728 
3729 	if (mddev_trylock(mddev)==0) {
3730 		int spares =0;
3731 
3732 		spin_lock(&mddev->write_lock);
3733 		if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
3734 		    !mddev->in_sync && mddev->recovery_cp == MaxSector) {
3735 			mddev->in_sync = 1;
3736 			mddev->sb_dirty = 1;
3737 		}
3738 		if (mddev->safemode == 1)
3739 			mddev->safemode = 0;
3740 		spin_unlock(&mddev->write_lock);
3741 
3742 		if (mddev->sb_dirty)
3743 			md_update_sb(mddev);
3744 
3745 
3746 		if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
3747 		    !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
3748 			/* resync/recovery still happening */
3749 			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3750 			goto unlock;
3751 		}
3752 		if (mddev->sync_thread) {
3753 			/* resync has finished, collect result */
3754 			md_unregister_thread(mddev->sync_thread);
3755 			mddev->sync_thread = NULL;
3756 			if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
3757 			    !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
3758 				/* success...*/
3759 				/* activate any spares */
3760 				mddev->pers->spare_active(mddev);
3761 			}
3762 			md_update_sb(mddev);
3763 
3764 			/* if array is no-longer degraded, then any saved_raid_disk
3765 			 * information must be scrapped
3766 			 */
3767 			if (!mddev->degraded)
3768 				ITERATE_RDEV(mddev,rdev,rtmp)
3769 					rdev->saved_raid_disk = -1;
3770 
3771 			mddev->recovery = 0;
3772 			/* flag recovery needed just to double check */
3773 			set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3774 			goto unlock;
3775 		}
3776 		if (mddev->recovery)
3777 			/* probably just the RECOVERY_NEEDED flag */
3778 			mddev->recovery = 0;
3779 
3780 		/* no recovery is running.
3781 		 * remove any failed drives, then
3782 		 * add spares if possible.
3783 		 * Spare are also removed and re-added, to allow
3784 		 * the personality to fail the re-add.
3785 		 */
3786 		ITERATE_RDEV(mddev,rdev,rtmp)
3787 			if (rdev->raid_disk >= 0 &&
3788 			    (rdev->faulty || ! rdev->in_sync) &&
3789 			    atomic_read(&rdev->nr_pending)==0) {
3790 				if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
3791 					rdev->raid_disk = -1;
3792 			}
3793 
3794 		if (mddev->degraded) {
3795 			ITERATE_RDEV(mddev,rdev,rtmp)
3796 				if (rdev->raid_disk < 0
3797 				    && !rdev->faulty) {
3798 					if (mddev->pers->hot_add_disk(mddev,rdev))
3799 						spares++;
3800 					else
3801 						break;
3802 				}
3803 		}
3804 
3805 		if (!spares && (mddev->recovery_cp == MaxSector )) {
3806 			/* nothing we can do ... */
3807 			goto unlock;
3808 		}
3809 		if (mddev->pers->sync_request) {
3810 			set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
3811 			if (!spares)
3812 				set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3813 			if (spares && mddev->bitmap && ! mddev->bitmap->file) {
3814 				/* We are adding a device or devices to an array
3815 				 * which has the bitmap stored on all devices.
3816 				 * So make sure all bitmap pages get written
3817 				 */
3818 				bitmap_write_all(mddev->bitmap);
3819 			}
3820 			mddev->sync_thread = md_register_thread(md_do_sync,
3821 								mddev,
3822 								"%s_resync");
3823 			if (!mddev->sync_thread) {
3824 				printk(KERN_ERR "%s: could not start resync"
3825 					" thread...\n",
3826 					mdname(mddev));
3827 				/* leave the spares where they are, it shouldn't hurt */
3828 				mddev->recovery = 0;
3829 			} else {
3830 				md_wakeup_thread(mddev->sync_thread);
3831 			}
3832 		}
3833 	unlock:
3834 		mddev_unlock(mddev);
3835 	}
3836 }
3837 
3838 static int md_notify_reboot(struct notifier_block *this,
3839 			    unsigned long code, void *x)
3840 {
3841 	struct list_head *tmp;
3842 	mddev_t *mddev;
3843 
3844 	if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
3845 
3846 		printk(KERN_INFO "md: stopping all md devices.\n");
3847 
3848 		ITERATE_MDDEV(mddev,tmp)
3849 			if (mddev_trylock(mddev)==0)
3850 				do_md_stop (mddev, 1);
3851 		/*
3852 		 * certain more exotic SCSI devices are known to be
3853 		 * volatile wrt too early system reboots. While the
3854 		 * right place to handle this issue is the given
3855 		 * driver, we do want to have a safe RAID driver ...
3856 		 */
3857 		mdelay(1000*1);
3858 	}
3859 	return NOTIFY_DONE;
3860 }
3861 
3862 static struct notifier_block md_notifier = {
3863 	.notifier_call	= md_notify_reboot,
3864 	.next		= NULL,
3865 	.priority	= INT_MAX, /* before any real devices */
3866 };
3867 
3868 static void md_geninit(void)
3869 {
3870 	struct proc_dir_entry *p;
3871 
3872 	dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
3873 
3874 	p = create_proc_entry("mdstat", S_IRUGO, NULL);
3875 	if (p)
3876 		p->proc_fops = &md_seq_fops;
3877 }
3878 
3879 static int __init md_init(void)
3880 {
3881 	int minor;
3882 
3883 	printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
3884 			" MD_SB_DISKS=%d\n",
3885 			MD_MAJOR_VERSION, MD_MINOR_VERSION,
3886 			MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
3887 	printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR,
3888 			BITMAP_MINOR);
3889 
3890 	if (register_blkdev(MAJOR_NR, "md"))
3891 		return -1;
3892 	if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
3893 		unregister_blkdev(MAJOR_NR, "md");
3894 		return -1;
3895 	}
3896 	devfs_mk_dir("md");
3897 	blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
3898 				md_probe, NULL, NULL);
3899 	blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
3900 			    md_probe, NULL, NULL);
3901 
3902 	for (minor=0; minor < MAX_MD_DEVS; ++minor)
3903 		devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
3904 				S_IFBLK|S_IRUSR|S_IWUSR,
3905 				"md/%d", minor);
3906 
3907 	for (minor=0; minor < MAX_MD_DEVS; ++minor)
3908 		devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
3909 			      S_IFBLK|S_IRUSR|S_IWUSR,
3910 			      "md/mdp%d", minor);
3911 
3912 
3913 	register_reboot_notifier(&md_notifier);
3914 	raid_table_header = register_sysctl_table(raid_root_table, 1);
3915 
3916 	md_geninit();
3917 	return (0);
3918 }
3919 
3920 
3921 #ifndef MODULE
3922 
3923 /*
3924  * Searches all registered partitions for autorun RAID arrays
3925  * at boot time.
3926  */
3927 static dev_t detected_devices[128];
3928 static int dev_cnt;
3929 
3930 void md_autodetect_dev(dev_t dev)
3931 {
3932 	if (dev_cnt >= 0 && dev_cnt < 127)
3933 		detected_devices[dev_cnt++] = dev;
3934 }
3935 
3936 
3937 static void autostart_arrays(int part)
3938 {
3939 	mdk_rdev_t *rdev;
3940 	int i;
3941 
3942 	printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
3943 
3944 	for (i = 0; i < dev_cnt; i++) {
3945 		dev_t dev = detected_devices[i];
3946 
3947 		rdev = md_import_device(dev,0, 0);
3948 		if (IS_ERR(rdev))
3949 			continue;
3950 
3951 		if (rdev->faulty) {
3952 			MD_BUG();
3953 			continue;
3954 		}
3955 		list_add(&rdev->same_set, &pending_raid_disks);
3956 	}
3957 	dev_cnt = 0;
3958 
3959 	autorun_devices(part);
3960 }
3961 
3962 #endif
3963 
3964 static __exit void md_exit(void)
3965 {
3966 	mddev_t *mddev;
3967 	struct list_head *tmp;
3968 	int i;
3969 	blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
3970 	blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
3971 	for (i=0; i < MAX_MD_DEVS; i++)
3972 		devfs_remove("md/%d", i);
3973 	for (i=0; i < MAX_MD_DEVS; i++)
3974 		devfs_remove("md/d%d", i);
3975 
3976 	devfs_remove("md");
3977 
3978 	unregister_blkdev(MAJOR_NR,"md");
3979 	unregister_blkdev(mdp_major, "mdp");
3980 	unregister_reboot_notifier(&md_notifier);
3981 	unregister_sysctl_table(raid_table_header);
3982 	remove_proc_entry("mdstat", NULL);
3983 	ITERATE_MDDEV(mddev,tmp) {
3984 		struct gendisk *disk = mddev->gendisk;
3985 		if (!disk)
3986 			continue;
3987 		export_array(mddev);
3988 		del_gendisk(disk);
3989 		put_disk(disk);
3990 		mddev->gendisk = NULL;
3991 		mddev_put(mddev);
3992 	}
3993 }
3994 
3995 module_init(md_init)
3996 module_exit(md_exit)
3997 
3998 EXPORT_SYMBOL(register_md_personality);
3999 EXPORT_SYMBOL(unregister_md_personality);
4000 EXPORT_SYMBOL(md_error);
4001 EXPORT_SYMBOL(md_done_sync);
4002 EXPORT_SYMBOL(md_write_start);
4003 EXPORT_SYMBOL(md_write_end);
4004 EXPORT_SYMBOL(md_register_thread);
4005 EXPORT_SYMBOL(md_unregister_thread);
4006 EXPORT_SYMBOL(md_wakeup_thread);
4007 EXPORT_SYMBOL(md_print_devices);
4008 EXPORT_SYMBOL(md_check_recovery);
4009 MODULE_LICENSE("GPL");
4010