md: export 'frozen' resync state through sysfs
[linux-2.6.git] / drivers / md / md.c
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/kthread.h>
36 #include <linux/blkdev.h>
37 #include <linux/sysctl.h>
38 #include <linux/seq_file.h>
39 #include <linux/buffer_head.h> /* for invalidate_bdev */
40 #include <linux/poll.h>
41 #include <linux/ctype.h>
42 #include <linux/hdreg.h>
43 #include <linux/proc_fs.h>
44 #include <linux/random.h>
45 #include <linux/reboot.h>
46 #include <linux/file.h>
47 #include <linux/delay.h>
48 #include <linux/raid/md_p.h>
49 #include <linux/raid/md_u.h>
50 #include "md.h"
51 #include "bitmap.h"
52
53 #define DEBUG 0
54 #define dprintk(x...) ((void)(DEBUG && printk(x)))
55
56
57 #ifndef MODULE
58 static void autostart_arrays(int part);
59 #endif
60
61 static LIST_HEAD(pers_list);
62 static DEFINE_SPINLOCK(pers_lock);
63
64 static void md_print_devices(void);
65
66 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
67
68 #define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
69
70 /*
71  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
72  * is 1000 KB/sec, so the extra system load does not show up that much.
73  * Increase it if you want to have more _guaranteed_ speed. Note that
74  * the RAID driver will use the maximum available bandwidth if the IO
75  * subsystem is idle. There is also an 'absolute maximum' reconstruction
76  * speed limit - in case reconstruction slows down your system despite
77  * idle IO detection.
78  *
79  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
80  * or /sys/block/mdX/md/sync_speed_{min,max}
81  */
82
83 static int sysctl_speed_limit_min = 1000;
84 static int sysctl_speed_limit_max = 200000;
85 static inline int speed_min(mddev_t *mddev)
86 {
87         return mddev->sync_speed_min ?
88                 mddev->sync_speed_min : sysctl_speed_limit_min;
89 }
90
91 static inline int speed_max(mddev_t *mddev)
92 {
93         return mddev->sync_speed_max ?
94                 mddev->sync_speed_max : sysctl_speed_limit_max;
95 }
96
97 static struct ctl_table_header *raid_table_header;
98
99 static ctl_table raid_table[] = {
100         {
101                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
102                 .procname       = "speed_limit_min",
103                 .data           = &sysctl_speed_limit_min,
104                 .maxlen         = sizeof(int),
105                 .mode           = S_IRUGO|S_IWUSR,
106                 .proc_handler   = &proc_dointvec,
107         },
108         {
109                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
110                 .procname       = "speed_limit_max",
111                 .data           = &sysctl_speed_limit_max,
112                 .maxlen         = sizeof(int),
113                 .mode           = S_IRUGO|S_IWUSR,
114                 .proc_handler   = &proc_dointvec,
115         },
116         { .ctl_name = 0 }
117 };
118
119 static ctl_table raid_dir_table[] = {
120         {
121                 .ctl_name       = DEV_RAID,
122                 .procname       = "raid",
123                 .maxlen         = 0,
124                 .mode           = S_IRUGO|S_IXUGO,
125                 .child          = raid_table,
126         },
127         { .ctl_name = 0 }
128 };
129
130 static ctl_table raid_root_table[] = {
131         {
132                 .ctl_name       = CTL_DEV,
133                 .procname       = "dev",
134                 .maxlen         = 0,
135                 .mode           = 0555,
136                 .child          = raid_dir_table,
137         },
138         { .ctl_name = 0 }
139 };
140
141 static struct block_device_operations md_fops;
142
143 static int start_readonly;
144
145 /*
146  * We have a system wide 'event count' that is incremented
147  * on any 'interesting' event, and readers of /proc/mdstat
148  * can use 'poll' or 'select' to find out when the event
149  * count increases.
150  *
151  * Events are:
152  *  start array, stop array, error, add device, remove device,
153  *  start build, activate spare
154  */
155 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
156 static atomic_t md_event_count;
157 void md_new_event(mddev_t *mddev)
158 {
159         atomic_inc(&md_event_count);
160         wake_up(&md_event_waiters);
161 }
162 EXPORT_SYMBOL_GPL(md_new_event);
163
164 /* Alternate version that can be called from interrupts
165  * when calling sysfs_notify isn't needed.
166  */
167 static void md_new_event_inintr(mddev_t *mddev)
168 {
169         atomic_inc(&md_event_count);
170         wake_up(&md_event_waiters);
171 }
172
173 /*
174  * Enables to iterate over all existing md arrays
175  * all_mddevs_lock protects this list.
176  */
177 static LIST_HEAD(all_mddevs);
178 static DEFINE_SPINLOCK(all_mddevs_lock);
179
180
181 /*
182  * iterates through all used mddevs in the system.
183  * We take care to grab the all_mddevs_lock whenever navigating
184  * the list, and to always hold a refcount when unlocked.
185  * Any code which breaks out of this loop while own
186  * a reference to the current mddev and must mddev_put it.
187  */
188 #define for_each_mddev(mddev,tmp)                                       \
189                                                                         \
190         for (({ spin_lock(&all_mddevs_lock);                            \
191                 tmp = all_mddevs.next;                                  \
192                 mddev = NULL;});                                        \
193              ({ if (tmp != &all_mddevs)                                 \
194                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
195                 spin_unlock(&all_mddevs_lock);                          \
196                 if (mddev) mddev_put(mddev);                            \
197                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
198                 tmp != &all_mddevs;});                                  \
199              ({ spin_lock(&all_mddevs_lock);                            \
200                 tmp = tmp->next;})                                      \
201                 )
202
203
204 /* Rather than calling directly into the personality make_request function,
205  * IO requests come here first so that we can check if the device is
206  * being suspended pending a reconfiguration.
207  * We hold a refcount over the call to ->make_request.  By the time that
208  * call has finished, the bio has been linked into some internal structure
209  * and so is visible to ->quiesce(), so we don't need the refcount any more.
210  */
211 static int md_make_request(struct request_queue *q, struct bio *bio)
212 {
213         mddev_t *mddev = q->queuedata;
214         int rv;
215         if (mddev == NULL || mddev->pers == NULL) {
216                 bio_io_error(bio);
217                 return 0;
218         }
219         rcu_read_lock();
220         if (mddev->suspended) {
221                 DEFINE_WAIT(__wait);
222                 for (;;) {
223                         prepare_to_wait(&mddev->sb_wait, &__wait,
224                                         TASK_UNINTERRUPTIBLE);
225                         if (!mddev->suspended)
226                                 break;
227                         rcu_read_unlock();
228                         schedule();
229                         rcu_read_lock();
230                 }
231                 finish_wait(&mddev->sb_wait, &__wait);
232         }
233         atomic_inc(&mddev->active_io);
234         rcu_read_unlock();
235         rv = mddev->pers->make_request(q, bio);
236         if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
237                 wake_up(&mddev->sb_wait);
238
239         return rv;
240 }
241
242 static void mddev_suspend(mddev_t *mddev)
243 {
244         BUG_ON(mddev->suspended);
245         mddev->suspended = 1;
246         synchronize_rcu();
247         wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
248         mddev->pers->quiesce(mddev, 1);
249         md_unregister_thread(mddev->thread);
250         mddev->thread = NULL;
251         /* we now know that no code is executing in the personality module,
252          * except possibly the tail end of a ->bi_end_io function, but that
253          * is certain to complete before the module has a chance to get
254          * unloaded
255          */
256 }
257
258 static void mddev_resume(mddev_t *mddev)
259 {
260         mddev->suspended = 0;
261         wake_up(&mddev->sb_wait);
262         mddev->pers->quiesce(mddev, 0);
263 }
264
265
266 static inline mddev_t *mddev_get(mddev_t *mddev)
267 {
268         atomic_inc(&mddev->active);
269         return mddev;
270 }
271
272 static void mddev_delayed_delete(struct work_struct *ws);
273
274 static void mddev_put(mddev_t *mddev)
275 {
276         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
277                 return;
278         if (!mddev->raid_disks && list_empty(&mddev->disks) &&
279             !mddev->hold_active) {
280                 list_del(&mddev->all_mddevs);
281                 if (mddev->gendisk) {
282                         /* we did a probe so need to clean up.
283                          * Call schedule_work inside the spinlock
284                          * so that flush_scheduled_work() after
285                          * mddev_find will succeed in waiting for the
286                          * work to be done.
287                          */
288                         INIT_WORK(&mddev->del_work, mddev_delayed_delete);
289                         schedule_work(&mddev->del_work);
290                 } else
291                         kfree(mddev);
292         }
293         spin_unlock(&all_mddevs_lock);
294 }
295
296 static mddev_t * mddev_find(dev_t unit)
297 {
298         mddev_t *mddev, *new = NULL;
299
300  retry:
301         spin_lock(&all_mddevs_lock);
302
303         if (unit) {
304                 list_for_each_entry(mddev, &all_mddevs, all_mddevs)
305                         if (mddev->unit == unit) {
306                                 mddev_get(mddev);
307                                 spin_unlock(&all_mddevs_lock);
308                                 kfree(new);
309                                 return mddev;
310                         }
311
312                 if (new) {
313                         list_add(&new->all_mddevs, &all_mddevs);
314                         spin_unlock(&all_mddevs_lock);
315                         new->hold_active = UNTIL_IOCTL;
316                         return new;
317                 }
318         } else if (new) {
319                 /* find an unused unit number */
320                 static int next_minor = 512;
321                 int start = next_minor;
322                 int is_free = 0;
323                 int dev = 0;
324                 while (!is_free) {
325                         dev = MKDEV(MD_MAJOR, next_minor);
326                         next_minor++;
327                         if (next_minor > MINORMASK)
328                                 next_minor = 0;
329                         if (next_minor == start) {
330                                 /* Oh dear, all in use. */
331                                 spin_unlock(&all_mddevs_lock);
332                                 kfree(new);
333                                 return NULL;
334                         }
335                                 
336                         is_free = 1;
337                         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
338                                 if (mddev->unit == dev) {
339                                         is_free = 0;
340                                         break;
341                                 }
342                 }
343                 new->unit = dev;
344                 new->md_minor = MINOR(dev);
345                 new->hold_active = UNTIL_STOP;
346                 list_add(&new->all_mddevs, &all_mddevs);
347                 spin_unlock(&all_mddevs_lock);
348                 return new;
349         }
350         spin_unlock(&all_mddevs_lock);
351
352         new = kzalloc(sizeof(*new), GFP_KERNEL);
353         if (!new)
354                 return NULL;
355
356         new->unit = unit;
357         if (MAJOR(unit) == MD_MAJOR)
358                 new->md_minor = MINOR(unit);
359         else
360                 new->md_minor = MINOR(unit) >> MdpMinorShift;
361
362         mutex_init(&new->reconfig_mutex);
363         INIT_LIST_HEAD(&new->disks);
364         INIT_LIST_HEAD(&new->all_mddevs);
365         init_timer(&new->safemode_timer);
366         atomic_set(&new->active, 1);
367         atomic_set(&new->openers, 0);
368         atomic_set(&new->active_io, 0);
369         spin_lock_init(&new->write_lock);
370         init_waitqueue_head(&new->sb_wait);
371         init_waitqueue_head(&new->recovery_wait);
372         new->reshape_position = MaxSector;
373         new->resync_min = 0;
374         new->resync_max = MaxSector;
375         new->level = LEVEL_NONE;
376
377         goto retry;
378 }
379
380 static inline int mddev_lock(mddev_t * mddev)
381 {
382         return mutex_lock_interruptible(&mddev->reconfig_mutex);
383 }
384
385 static inline int mddev_is_locked(mddev_t *mddev)
386 {
387         return mutex_is_locked(&mddev->reconfig_mutex);
388 }
389
390 static inline int mddev_trylock(mddev_t * mddev)
391 {
392         return mutex_trylock(&mddev->reconfig_mutex);
393 }
394
395 static inline void mddev_unlock(mddev_t * mddev)
396 {
397         mutex_unlock(&mddev->reconfig_mutex);
398
399         md_wakeup_thread(mddev->thread);
400 }
401
402 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
403 {
404         mdk_rdev_t *rdev;
405
406         list_for_each_entry(rdev, &mddev->disks, same_set)
407                 if (rdev->desc_nr == nr)
408                         return rdev;
409
410         return NULL;
411 }
412
413 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
414 {
415         mdk_rdev_t *rdev;
416
417         list_for_each_entry(rdev, &mddev->disks, same_set)
418                 if (rdev->bdev->bd_dev == dev)
419                         return rdev;
420
421         return NULL;
422 }
423
424 static struct mdk_personality *find_pers(int level, char *clevel)
425 {
426         struct mdk_personality *pers;
427         list_for_each_entry(pers, &pers_list, list) {
428                 if (level != LEVEL_NONE && pers->level == level)
429                         return pers;
430                 if (strcmp(pers->name, clevel)==0)
431                         return pers;
432         }
433         return NULL;
434 }
435
436 /* return the offset of the super block in 512byte sectors */
437 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
438 {
439         sector_t num_sectors = bdev->bd_inode->i_size / 512;
440         return MD_NEW_SIZE_SECTORS(num_sectors);
441 }
442
443 static sector_t calc_num_sectors(mdk_rdev_t *rdev, unsigned chunk_size)
444 {
445         sector_t num_sectors = rdev->sb_start;
446
447         if (chunk_size)
448                 num_sectors &= ~((sector_t)chunk_size/512 - 1);
449         return num_sectors;
450 }
451
452 static int alloc_disk_sb(mdk_rdev_t * rdev)
453 {
454         if (rdev->sb_page)
455                 MD_BUG();
456
457         rdev->sb_page = alloc_page(GFP_KERNEL);
458         if (!rdev->sb_page) {
459                 printk(KERN_ALERT "md: out of memory.\n");
460                 return -ENOMEM;
461         }
462
463         return 0;
464 }
465
466 static void free_disk_sb(mdk_rdev_t * rdev)
467 {
468         if (rdev->sb_page) {
469                 put_page(rdev->sb_page);
470                 rdev->sb_loaded = 0;
471                 rdev->sb_page = NULL;
472                 rdev->sb_start = 0;
473                 rdev->sectors = 0;
474         }
475 }
476
477
478 static void super_written(struct bio *bio, int error)
479 {
480         mdk_rdev_t *rdev = bio->bi_private;
481         mddev_t *mddev = rdev->mddev;
482
483         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags)) {
484                 printk("md: super_written gets error=%d, uptodate=%d\n",
485                        error, test_bit(BIO_UPTODATE, &bio->bi_flags));
486                 WARN_ON(test_bit(BIO_UPTODATE, &bio->bi_flags));
487                 md_error(mddev, rdev);
488         }
489
490         if (atomic_dec_and_test(&mddev->pending_writes))
491                 wake_up(&mddev->sb_wait);
492         bio_put(bio);
493 }
494
495 static void super_written_barrier(struct bio *bio, int error)
496 {
497         struct bio *bio2 = bio->bi_private;
498         mdk_rdev_t *rdev = bio2->bi_private;
499         mddev_t *mddev = rdev->mddev;
500
501         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) &&
502             error == -EOPNOTSUPP) {
503                 unsigned long flags;
504                 /* barriers don't appear to be supported :-( */
505                 set_bit(BarriersNotsupp, &rdev->flags);
506                 mddev->barriers_work = 0;
507                 spin_lock_irqsave(&mddev->write_lock, flags);
508                 bio2->bi_next = mddev->biolist;
509                 mddev->biolist = bio2;
510                 spin_unlock_irqrestore(&mddev->write_lock, flags);
511                 wake_up(&mddev->sb_wait);
512                 bio_put(bio);
513         } else {
514                 bio_put(bio2);
515                 bio->bi_private = rdev;
516                 super_written(bio, error);
517         }
518 }
519
520 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
521                    sector_t sector, int size, struct page *page)
522 {
523         /* write first size bytes of page to sector of rdev
524          * Increment mddev->pending_writes before returning
525          * and decrement it on completion, waking up sb_wait
526          * if zero is reached.
527          * If an error occurred, call md_error
528          *
529          * As we might need to resubmit the request if BIO_RW_BARRIER
530          * causes ENOTSUPP, we allocate a spare bio...
531          */
532         struct bio *bio = bio_alloc(GFP_NOIO, 1);
533         int rw = (1<<BIO_RW) | (1<<BIO_RW_SYNCIO) | (1<<BIO_RW_UNPLUG);
534
535         bio->bi_bdev = rdev->bdev;
536         bio->bi_sector = sector;
537         bio_add_page(bio, page, size, 0);
538         bio->bi_private = rdev;
539         bio->bi_end_io = super_written;
540         bio->bi_rw = rw;
541
542         atomic_inc(&mddev->pending_writes);
543         if (!test_bit(BarriersNotsupp, &rdev->flags)) {
544                 struct bio *rbio;
545                 rw |= (1<<BIO_RW_BARRIER);
546                 rbio = bio_clone(bio, GFP_NOIO);
547                 rbio->bi_private = bio;
548                 rbio->bi_end_io = super_written_barrier;
549                 submit_bio(rw, rbio);
550         } else
551                 submit_bio(rw, bio);
552 }
553
554 void md_super_wait(mddev_t *mddev)
555 {
556         /* wait for all superblock writes that were scheduled to complete.
557          * if any had to be retried (due to BARRIER problems), retry them
558          */
559         DEFINE_WAIT(wq);
560         for(;;) {
561                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
562                 if (atomic_read(&mddev->pending_writes)==0)
563                         break;
564                 while (mddev->biolist) {
565                         struct bio *bio;
566                         spin_lock_irq(&mddev->write_lock);
567                         bio = mddev->biolist;
568                         mddev->biolist = bio->bi_next ;
569                         bio->bi_next = NULL;
570                         spin_unlock_irq(&mddev->write_lock);
571                         submit_bio(bio->bi_rw, bio);
572                 }
573                 schedule();
574         }
575         finish_wait(&mddev->sb_wait, &wq);
576 }
577
578 static void bi_complete(struct bio *bio, int error)
579 {
580         complete((struct completion*)bio->bi_private);
581 }
582
583 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
584                    struct page *page, int rw)
585 {
586         struct bio *bio = bio_alloc(GFP_NOIO, 1);
587         struct completion event;
588         int ret;
589
590         rw |= (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
591
592         bio->bi_bdev = bdev;
593         bio->bi_sector = sector;
594         bio_add_page(bio, page, size, 0);
595         init_completion(&event);
596         bio->bi_private = &event;
597         bio->bi_end_io = bi_complete;
598         submit_bio(rw, bio);
599         wait_for_completion(&event);
600
601         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
602         bio_put(bio);
603         return ret;
604 }
605 EXPORT_SYMBOL_GPL(sync_page_io);
606
607 static int read_disk_sb(mdk_rdev_t * rdev, int size)
608 {
609         char b[BDEVNAME_SIZE];
610         if (!rdev->sb_page) {
611                 MD_BUG();
612                 return -EINVAL;
613         }
614         if (rdev->sb_loaded)
615                 return 0;
616
617
618         if (!sync_page_io(rdev->bdev, rdev->sb_start, size, rdev->sb_page, READ))
619                 goto fail;
620         rdev->sb_loaded = 1;
621         return 0;
622
623 fail:
624         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
625                 bdevname(rdev->bdev,b));
626         return -EINVAL;
627 }
628
629 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
630 {
631         return  sb1->set_uuid0 == sb2->set_uuid0 &&
632                 sb1->set_uuid1 == sb2->set_uuid1 &&
633                 sb1->set_uuid2 == sb2->set_uuid2 &&
634                 sb1->set_uuid3 == sb2->set_uuid3;
635 }
636
637 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
638 {
639         int ret;
640         mdp_super_t *tmp1, *tmp2;
641
642         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
643         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
644
645         if (!tmp1 || !tmp2) {
646                 ret = 0;
647                 printk(KERN_INFO "md.c sb_equal(): failed to allocate memory!\n");
648                 goto abort;
649         }
650
651         *tmp1 = *sb1;
652         *tmp2 = *sb2;
653
654         /*
655          * nr_disks is not constant
656          */
657         tmp1->nr_disks = 0;
658         tmp2->nr_disks = 0;
659
660         ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
661 abort:
662         kfree(tmp1);
663         kfree(tmp2);
664         return ret;
665 }
666
667
668 static u32 md_csum_fold(u32 csum)
669 {
670         csum = (csum & 0xffff) + (csum >> 16);
671         return (csum & 0xffff) + (csum >> 16);
672 }
673
674 static unsigned int calc_sb_csum(mdp_super_t * sb)
675 {
676         u64 newcsum = 0;
677         u32 *sb32 = (u32*)sb;
678         int i;
679         unsigned int disk_csum, csum;
680
681         disk_csum = sb->sb_csum;
682         sb->sb_csum = 0;
683
684         for (i = 0; i < MD_SB_BYTES/4 ; i++)
685                 newcsum += sb32[i];
686         csum = (newcsum & 0xffffffff) + (newcsum>>32);
687
688
689 #ifdef CONFIG_ALPHA
690         /* This used to use csum_partial, which was wrong for several
691          * reasons including that different results are returned on
692          * different architectures.  It isn't critical that we get exactly
693          * the same return value as before (we always csum_fold before
694          * testing, and that removes any differences).  However as we
695          * know that csum_partial always returned a 16bit value on
696          * alphas, do a fold to maximise conformity to previous behaviour.
697          */
698         sb->sb_csum = md_csum_fold(disk_csum);
699 #else
700         sb->sb_csum = disk_csum;
701 #endif
702         return csum;
703 }
704
705
706 /*
707  * Handle superblock details.
708  * We want to be able to handle multiple superblock formats
709  * so we have a common interface to them all, and an array of
710  * different handlers.
711  * We rely on user-space to write the initial superblock, and support
712  * reading and updating of superblocks.
713  * Interface methods are:
714  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
715  *      loads and validates a superblock on dev.
716  *      if refdev != NULL, compare superblocks on both devices
717  *    Return:
718  *      0 - dev has a superblock that is compatible with refdev
719  *      1 - dev has a superblock that is compatible and newer than refdev
720  *          so dev should be used as the refdev in future
721  *     -EINVAL superblock incompatible or invalid
722  *     -othererror e.g. -EIO
723  *
724  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
725  *      Verify that dev is acceptable into mddev.
726  *       The first time, mddev->raid_disks will be 0, and data from
727  *       dev should be merged in.  Subsequent calls check that dev
728  *       is new enough.  Return 0 or -EINVAL
729  *
730  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
731  *     Update the superblock for rdev with data in mddev
732  *     This does not write to disc.
733  *
734  */
735
736 struct super_type  {
737         char                *name;
738         struct module       *owner;
739         int                 (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev,
740                                           int minor_version);
741         int                 (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
742         void                (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
743         unsigned long long  (*rdev_size_change)(mdk_rdev_t *rdev,
744                                                 sector_t num_sectors);
745 };
746
747 /*
748  * load_super for 0.90.0 
749  */
750 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
751 {
752         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
753         mdp_super_t *sb;
754         int ret;
755
756         /*
757          * Calculate the position of the superblock (512byte sectors),
758          * it's at the end of the disk.
759          *
760          * It also happens to be a multiple of 4Kb.
761          */
762         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
763
764         ret = read_disk_sb(rdev, MD_SB_BYTES);
765         if (ret) return ret;
766
767         ret = -EINVAL;
768
769         bdevname(rdev->bdev, b);
770         sb = (mdp_super_t*)page_address(rdev->sb_page);
771
772         if (sb->md_magic != MD_SB_MAGIC) {
773                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
774                        b);
775                 goto abort;
776         }
777
778         if (sb->major_version != 0 ||
779             sb->minor_version < 90 ||
780             sb->minor_version > 91) {
781                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
782                         sb->major_version, sb->minor_version,
783                         b);
784                 goto abort;
785         }
786
787         if (sb->raid_disks <= 0)
788                 goto abort;
789
790         if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
791                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
792                         b);
793                 goto abort;
794         }
795
796         rdev->preferred_minor = sb->md_minor;
797         rdev->data_offset = 0;
798         rdev->sb_size = MD_SB_BYTES;
799
800         if (sb->state & (1<<MD_SB_BITMAP_PRESENT)) {
801                 if (sb->level != 1 && sb->level != 4
802                     && sb->level != 5 && sb->level != 6
803                     && sb->level != 10) {
804                         /* FIXME use a better test */
805                         printk(KERN_WARNING
806                                "md: bitmaps not supported for this level.\n");
807                         goto abort;
808                 }
809         }
810
811         if (sb->level == LEVEL_MULTIPATH)
812                 rdev->desc_nr = -1;
813         else
814                 rdev->desc_nr = sb->this_disk.number;
815
816         if (!refdev) {
817                 ret = 1;
818         } else {
819                 __u64 ev1, ev2;
820                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
821                 if (!uuid_equal(refsb, sb)) {
822                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
823                                 b, bdevname(refdev->bdev,b2));
824                         goto abort;
825                 }
826                 if (!sb_equal(refsb, sb)) {
827                         printk(KERN_WARNING "md: %s has same UUID"
828                                " but different superblock to %s\n",
829                                b, bdevname(refdev->bdev, b2));
830                         goto abort;
831                 }
832                 ev1 = md_event(sb);
833                 ev2 = md_event(refsb);
834                 if (ev1 > ev2)
835                         ret = 1;
836                 else 
837                         ret = 0;
838         }
839         rdev->sectors = calc_num_sectors(rdev, sb->chunk_size);
840
841         if (rdev->sectors < sb->size * 2 && sb->level > 1)
842                 /* "this cannot possibly happen" ... */
843                 ret = -EINVAL;
844
845  abort:
846         return ret;
847 }
848
849 /*
850  * validate_super for 0.90.0
851  */
852 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
853 {
854         mdp_disk_t *desc;
855         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
856         __u64 ev1 = md_event(sb);
857
858         rdev->raid_disk = -1;
859         clear_bit(Faulty, &rdev->flags);
860         clear_bit(In_sync, &rdev->flags);
861         clear_bit(WriteMostly, &rdev->flags);
862         clear_bit(BarriersNotsupp, &rdev->flags);
863
864         if (mddev->raid_disks == 0) {
865                 mddev->major_version = 0;
866                 mddev->minor_version = sb->minor_version;
867                 mddev->patch_version = sb->patch_version;
868                 mddev->external = 0;
869                 mddev->chunk_size = sb->chunk_size;
870                 mddev->ctime = sb->ctime;
871                 mddev->utime = sb->utime;
872                 mddev->level = sb->level;
873                 mddev->clevel[0] = 0;
874                 mddev->layout = sb->layout;
875                 mddev->raid_disks = sb->raid_disks;
876                 mddev->dev_sectors = sb->size * 2;
877                 mddev->events = ev1;
878                 mddev->bitmap_offset = 0;
879                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
880
881                 if (mddev->minor_version >= 91) {
882                         mddev->reshape_position = sb->reshape_position;
883                         mddev->delta_disks = sb->delta_disks;
884                         mddev->new_level = sb->new_level;
885                         mddev->new_layout = sb->new_layout;
886                         mddev->new_chunk = sb->new_chunk;
887                 } else {
888                         mddev->reshape_position = MaxSector;
889                         mddev->delta_disks = 0;
890                         mddev->new_level = mddev->level;
891                         mddev->new_layout = mddev->layout;
892                         mddev->new_chunk = mddev->chunk_size;
893                 }
894
895                 if (sb->state & (1<<MD_SB_CLEAN))
896                         mddev->recovery_cp = MaxSector;
897                 else {
898                         if (sb->events_hi == sb->cp_events_hi && 
899                                 sb->events_lo == sb->cp_events_lo) {
900                                 mddev->recovery_cp = sb->recovery_cp;
901                         } else
902                                 mddev->recovery_cp = 0;
903                 }
904
905                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
906                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
907                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
908                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
909
910                 mddev->max_disks = MD_SB_DISKS;
911
912                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
913                     mddev->bitmap_file == NULL)
914                         mddev->bitmap_offset = mddev->default_bitmap_offset;
915
916         } else if (mddev->pers == NULL) {
917                 /* Insist on good event counter while assembling */
918                 ++ev1;
919                 if (ev1 < mddev->events) 
920                         return -EINVAL;
921         } else if (mddev->bitmap) {
922                 /* if adding to array with a bitmap, then we can accept an
923                  * older device ... but not too old.
924                  */
925                 if (ev1 < mddev->bitmap->events_cleared)
926                         return 0;
927         } else {
928                 if (ev1 < mddev->events)
929                         /* just a hot-add of a new device, leave raid_disk at -1 */
930                         return 0;
931         }
932
933         if (mddev->level != LEVEL_MULTIPATH) {
934                 desc = sb->disks + rdev->desc_nr;
935
936                 if (desc->state & (1<<MD_DISK_FAULTY))
937                         set_bit(Faulty, &rdev->flags);
938                 else if (desc->state & (1<<MD_DISK_SYNC) /* &&
939                             desc->raid_disk < mddev->raid_disks */) {
940                         set_bit(In_sync, &rdev->flags);
941                         rdev->raid_disk = desc->raid_disk;
942                 }
943                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
944                         set_bit(WriteMostly, &rdev->flags);
945         } else /* MULTIPATH are always insync */
946                 set_bit(In_sync, &rdev->flags);
947         return 0;
948 }
949
950 /*
951  * sync_super for 0.90.0
952  */
953 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
954 {
955         mdp_super_t *sb;
956         mdk_rdev_t *rdev2;
957         int next_spare = mddev->raid_disks;
958
959
960         /* make rdev->sb match mddev data..
961          *
962          * 1/ zero out disks
963          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
964          * 3/ any empty disks < next_spare become removed
965          *
966          * disks[0] gets initialised to REMOVED because
967          * we cannot be sure from other fields if it has
968          * been initialised or not.
969          */
970         int i;
971         int active=0, working=0,failed=0,spare=0,nr_disks=0;
972
973         rdev->sb_size = MD_SB_BYTES;
974
975         sb = (mdp_super_t*)page_address(rdev->sb_page);
976
977         memset(sb, 0, sizeof(*sb));
978
979         sb->md_magic = MD_SB_MAGIC;
980         sb->major_version = mddev->major_version;
981         sb->patch_version = mddev->patch_version;
982         sb->gvalid_words  = 0; /* ignored */
983         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
984         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
985         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
986         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
987
988         sb->ctime = mddev->ctime;
989         sb->level = mddev->level;
990         sb->size = mddev->dev_sectors / 2;
991         sb->raid_disks = mddev->raid_disks;
992         sb->md_minor = mddev->md_minor;
993         sb->not_persistent = 0;
994         sb->utime = mddev->utime;
995         sb->state = 0;
996         sb->events_hi = (mddev->events>>32);
997         sb->events_lo = (u32)mddev->events;
998
999         if (mddev->reshape_position == MaxSector)
1000                 sb->minor_version = 90;
1001         else {
1002                 sb->minor_version = 91;
1003                 sb->reshape_position = mddev->reshape_position;
1004                 sb->new_level = mddev->new_level;
1005                 sb->delta_disks = mddev->delta_disks;
1006                 sb->new_layout = mddev->new_layout;
1007                 sb->new_chunk = mddev->new_chunk;
1008         }
1009         mddev->minor_version = sb->minor_version;
1010         if (mddev->in_sync)
1011         {
1012                 sb->recovery_cp = mddev->recovery_cp;
1013                 sb->cp_events_hi = (mddev->events>>32);
1014                 sb->cp_events_lo = (u32)mddev->events;
1015                 if (mddev->recovery_cp == MaxSector)
1016                         sb->state = (1<< MD_SB_CLEAN);
1017         } else
1018                 sb->recovery_cp = 0;
1019
1020         sb->layout = mddev->layout;
1021         sb->chunk_size = mddev->chunk_size;
1022
1023         if (mddev->bitmap && mddev->bitmap_file == NULL)
1024                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
1025
1026         sb->disks[0].state = (1<<MD_DISK_REMOVED);
1027         list_for_each_entry(rdev2, &mddev->disks, same_set) {
1028                 mdp_disk_t *d;
1029                 int desc_nr;
1030                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
1031                     && !test_bit(Faulty, &rdev2->flags))
1032                         desc_nr = rdev2->raid_disk;
1033                 else
1034                         desc_nr = next_spare++;
1035                 rdev2->desc_nr = desc_nr;
1036                 d = &sb->disks[rdev2->desc_nr];
1037                 nr_disks++;
1038                 d->number = rdev2->desc_nr;
1039                 d->major = MAJOR(rdev2->bdev->bd_dev);
1040                 d->minor = MINOR(rdev2->bdev->bd_dev);
1041                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
1042                     && !test_bit(Faulty, &rdev2->flags))
1043                         d->raid_disk = rdev2->raid_disk;
1044                 else
1045                         d->raid_disk = rdev2->desc_nr; /* compatibility */
1046                 if (test_bit(Faulty, &rdev2->flags))
1047                         d->state = (1<<MD_DISK_FAULTY);
1048                 else if (test_bit(In_sync, &rdev2->flags)) {
1049                         d->state = (1<<MD_DISK_ACTIVE);
1050                         d->state |= (1<<MD_DISK_SYNC);
1051                         active++;
1052                         working++;
1053                 } else {
1054                         d->state = 0;
1055                         spare++;
1056                         working++;
1057                 }
1058                 if (test_bit(WriteMostly, &rdev2->flags))
1059                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
1060         }
1061         /* now set the "removed" and "faulty" bits on any missing devices */
1062         for (i=0 ; i < mddev->raid_disks ; i++) {
1063                 mdp_disk_t *d = &sb->disks[i];
1064                 if (d->state == 0 && d->number == 0) {
1065                         d->number = i;
1066                         d->raid_disk = i;
1067                         d->state = (1<<MD_DISK_REMOVED);
1068                         d->state |= (1<<MD_DISK_FAULTY);
1069                         failed++;
1070                 }
1071         }
1072         sb->nr_disks = nr_disks;
1073         sb->active_disks = active;
1074         sb->working_disks = working;
1075         sb->failed_disks = failed;
1076         sb->spare_disks = spare;
1077
1078         sb->this_disk = sb->disks[rdev->desc_nr];
1079         sb->sb_csum = calc_sb_csum(sb);
1080 }
1081
1082 /*
1083  * rdev_size_change for 0.90.0
1084  */
1085 static unsigned long long
1086 super_90_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
1087 {
1088         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1089                 return 0; /* component must fit device */
1090         if (rdev->mddev->bitmap_offset)
1091                 return 0; /* can't move bitmap */
1092         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
1093         if (!num_sectors || num_sectors > rdev->sb_start)
1094                 num_sectors = rdev->sb_start;
1095         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1096                        rdev->sb_page);
1097         md_super_wait(rdev->mddev);
1098         return num_sectors / 2; /* kB for sysfs */
1099 }
1100
1101
1102 /*
1103  * version 1 superblock
1104  */
1105
1106 static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
1107 {
1108         __le32 disk_csum;
1109         u32 csum;
1110         unsigned long long newcsum;
1111         int size = 256 + le32_to_cpu(sb->max_dev)*2;
1112         __le32 *isuper = (__le32*)sb;
1113         int i;
1114
1115         disk_csum = sb->sb_csum;
1116         sb->sb_csum = 0;
1117         newcsum = 0;
1118         for (i=0; size>=4; size -= 4 )
1119                 newcsum += le32_to_cpu(*isuper++);
1120
1121         if (size == 2)
1122                 newcsum += le16_to_cpu(*(__le16*) isuper);
1123
1124         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1125         sb->sb_csum = disk_csum;
1126         return cpu_to_le32(csum);
1127 }
1128
1129 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
1130 {
1131         struct mdp_superblock_1 *sb;
1132         int ret;
1133         sector_t sb_start;
1134         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1135         int bmask;
1136
1137         /*
1138          * Calculate the position of the superblock in 512byte sectors.
1139          * It is always aligned to a 4K boundary and
1140          * depeding on minor_version, it can be:
1141          * 0: At least 8K, but less than 12K, from end of device
1142          * 1: At start of device
1143          * 2: 4K from start of device.
1144          */
1145         switch(minor_version) {
1146         case 0:
1147                 sb_start = rdev->bdev->bd_inode->i_size >> 9;
1148                 sb_start -= 8*2;
1149                 sb_start &= ~(sector_t)(4*2-1);
1150                 break;
1151         case 1:
1152                 sb_start = 0;
1153                 break;
1154         case 2:
1155                 sb_start = 8;
1156                 break;
1157         default:
1158                 return -EINVAL;
1159         }
1160         rdev->sb_start = sb_start;
1161
1162         /* superblock is rarely larger than 1K, but it can be larger,
1163          * and it is safe to read 4k, so we do that
1164          */
1165         ret = read_disk_sb(rdev, 4096);
1166         if (ret) return ret;
1167
1168
1169         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1170
1171         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1172             sb->major_version != cpu_to_le32(1) ||
1173             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1174             le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1175             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1176                 return -EINVAL;
1177
1178         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1179                 printk("md: invalid superblock checksum on %s\n",
1180                         bdevname(rdev->bdev,b));
1181                 return -EINVAL;
1182         }
1183         if (le64_to_cpu(sb->data_size) < 10) {
1184                 printk("md: data_size too small on %s\n",
1185                        bdevname(rdev->bdev,b));
1186                 return -EINVAL;
1187         }
1188         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET)) {
1189                 if (sb->level != cpu_to_le32(1) &&
1190                     sb->level != cpu_to_le32(4) &&
1191                     sb->level != cpu_to_le32(5) &&
1192                     sb->level != cpu_to_le32(6) &&
1193                     sb->level != cpu_to_le32(10)) {
1194                         printk(KERN_WARNING
1195                                "md: bitmaps not supported for this level.\n");
1196                         return -EINVAL;
1197                 }
1198         }
1199
1200         rdev->preferred_minor = 0xffff;
1201         rdev->data_offset = le64_to_cpu(sb->data_offset);
1202         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1203
1204         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1205         bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
1206         if (rdev->sb_size & bmask)
1207                 rdev->sb_size = (rdev->sb_size | bmask) + 1;
1208
1209         if (minor_version
1210             && rdev->data_offset < sb_start + (rdev->sb_size/512))
1211                 return -EINVAL;
1212
1213         if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1214                 rdev->desc_nr = -1;
1215         else
1216                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1217
1218         if (!refdev) {
1219                 ret = 1;
1220         } else {
1221                 __u64 ev1, ev2;
1222                 struct mdp_superblock_1 *refsb = 
1223                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
1224
1225                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1226                     sb->level != refsb->level ||
1227                     sb->layout != refsb->layout ||
1228                     sb->chunksize != refsb->chunksize) {
1229                         printk(KERN_WARNING "md: %s has strangely different"
1230                                 " superblock to %s\n",
1231                                 bdevname(rdev->bdev,b),
1232                                 bdevname(refdev->bdev,b2));
1233                         return -EINVAL;
1234                 }
1235                 ev1 = le64_to_cpu(sb->events);
1236                 ev2 = le64_to_cpu(refsb->events);
1237
1238                 if (ev1 > ev2)
1239                         ret = 1;
1240                 else
1241                         ret = 0;
1242         }
1243         if (minor_version)
1244                 rdev->sectors = (rdev->bdev->bd_inode->i_size >> 9) -
1245                         le64_to_cpu(sb->data_offset);
1246         else
1247                 rdev->sectors = rdev->sb_start;
1248         if (rdev->sectors < le64_to_cpu(sb->data_size))
1249                 return -EINVAL;
1250         rdev->sectors = le64_to_cpu(sb->data_size);
1251         if (le32_to_cpu(sb->chunksize))
1252                 rdev->sectors &= ~((sector_t)le32_to_cpu(sb->chunksize) - 1);
1253
1254         if (le64_to_cpu(sb->size) > rdev->sectors)
1255                 return -EINVAL;
1256         return ret;
1257 }
1258
1259 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
1260 {
1261         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1262         __u64 ev1 = le64_to_cpu(sb->events);
1263
1264         rdev->raid_disk = -1;
1265         clear_bit(Faulty, &rdev->flags);
1266         clear_bit(In_sync, &rdev->flags);
1267         clear_bit(WriteMostly, &rdev->flags);
1268         clear_bit(BarriersNotsupp, &rdev->flags);
1269
1270         if (mddev->raid_disks == 0) {
1271                 mddev->major_version = 1;
1272                 mddev->patch_version = 0;
1273                 mddev->external = 0;
1274                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
1275                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1276                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1277                 mddev->level = le32_to_cpu(sb->level);
1278                 mddev->clevel[0] = 0;
1279                 mddev->layout = le32_to_cpu(sb->layout);
1280                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1281                 mddev->dev_sectors = le64_to_cpu(sb->size);
1282                 mddev->events = ev1;
1283                 mddev->bitmap_offset = 0;
1284                 mddev->default_bitmap_offset = 1024 >> 9;
1285                 
1286                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1287                 memcpy(mddev->uuid, sb->set_uuid, 16);
1288
1289                 mddev->max_disks =  (4096-256)/2;
1290
1291                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1292                     mddev->bitmap_file == NULL )
1293                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
1294
1295                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1296                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1297                         mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1298                         mddev->new_level = le32_to_cpu(sb->new_level);
1299                         mddev->new_layout = le32_to_cpu(sb->new_layout);
1300                         mddev->new_chunk = le32_to_cpu(sb->new_chunk)<<9;
1301                 } else {
1302                         mddev->reshape_position = MaxSector;
1303                         mddev->delta_disks = 0;
1304                         mddev->new_level = mddev->level;
1305                         mddev->new_layout = mddev->layout;
1306                         mddev->new_chunk = mddev->chunk_size;
1307                 }
1308
1309         } else if (mddev->pers == NULL) {
1310                 /* Insist of good event counter while assembling */
1311                 ++ev1;
1312                 if (ev1 < mddev->events)
1313                         return -EINVAL;
1314         } else if (mddev->bitmap) {
1315                 /* If adding to array with a bitmap, then we can accept an
1316                  * older device, but not too old.
1317                  */
1318                 if (ev1 < mddev->bitmap->events_cleared)
1319                         return 0;
1320         } else {
1321                 if (ev1 < mddev->events)
1322                         /* just a hot-add of a new device, leave raid_disk at -1 */
1323                         return 0;
1324         }
1325         if (mddev->level != LEVEL_MULTIPATH) {
1326                 int role;
1327                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1328                 switch(role) {
1329                 case 0xffff: /* spare */
1330                         break;
1331                 case 0xfffe: /* faulty */
1332                         set_bit(Faulty, &rdev->flags);
1333                         break;
1334                 default:
1335                         if ((le32_to_cpu(sb->feature_map) &
1336                              MD_FEATURE_RECOVERY_OFFSET))
1337                                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1338                         else
1339                                 set_bit(In_sync, &rdev->flags);
1340                         rdev->raid_disk = role;
1341                         break;
1342                 }
1343                 if (sb->devflags & WriteMostly1)
1344                         set_bit(WriteMostly, &rdev->flags);
1345         } else /* MULTIPATH are always insync */
1346                 set_bit(In_sync, &rdev->flags);
1347
1348         return 0;
1349 }
1350
1351 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
1352 {
1353         struct mdp_superblock_1 *sb;
1354         mdk_rdev_t *rdev2;
1355         int max_dev, i;
1356         /* make rdev->sb match mddev and rdev data. */
1357
1358         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1359
1360         sb->feature_map = 0;
1361         sb->pad0 = 0;
1362         sb->recovery_offset = cpu_to_le64(0);
1363         memset(sb->pad1, 0, sizeof(sb->pad1));
1364         memset(sb->pad2, 0, sizeof(sb->pad2));
1365         memset(sb->pad3, 0, sizeof(sb->pad3));
1366
1367         sb->utime = cpu_to_le64((__u64)mddev->utime);
1368         sb->events = cpu_to_le64(mddev->events);
1369         if (mddev->in_sync)
1370                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1371         else
1372                 sb->resync_offset = cpu_to_le64(0);
1373
1374         sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1375
1376         sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1377         sb->size = cpu_to_le64(mddev->dev_sectors);
1378         sb->chunksize = cpu_to_le32(mddev->chunk_size >> 9);
1379         sb->level = cpu_to_le32(mddev->level);
1380         sb->layout = cpu_to_le32(mddev->layout);
1381
1382         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1383                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1384                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1385         }
1386
1387         if (rdev->raid_disk >= 0 &&
1388             !test_bit(In_sync, &rdev->flags)) {
1389                 if (mddev->curr_resync_completed > rdev->recovery_offset)
1390                         rdev->recovery_offset = mddev->curr_resync_completed;
1391                 if (rdev->recovery_offset > 0) {
1392                         sb->feature_map |=
1393                                 cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1394                         sb->recovery_offset =
1395                                 cpu_to_le64(rdev->recovery_offset);
1396                 }
1397         }
1398
1399         if (mddev->reshape_position != MaxSector) {
1400                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1401                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1402                 sb->new_layout = cpu_to_le32(mddev->new_layout);
1403                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1404                 sb->new_level = cpu_to_le32(mddev->new_level);
1405                 sb->new_chunk = cpu_to_le32(mddev->new_chunk>>9);
1406         }
1407
1408         max_dev = 0;
1409         list_for_each_entry(rdev2, &mddev->disks, same_set)
1410                 if (rdev2->desc_nr+1 > max_dev)
1411                         max_dev = rdev2->desc_nr+1;
1412
1413         if (max_dev > le32_to_cpu(sb->max_dev))
1414                 sb->max_dev = cpu_to_le32(max_dev);
1415         for (i=0; i<max_dev;i++)
1416                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1417         
1418         list_for_each_entry(rdev2, &mddev->disks, same_set) {
1419                 i = rdev2->desc_nr;
1420                 if (test_bit(Faulty, &rdev2->flags))
1421                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1422                 else if (test_bit(In_sync, &rdev2->flags))
1423                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1424                 else if (rdev2->raid_disk >= 0 && rdev2->recovery_offset > 0)
1425                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1426                 else
1427                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1428         }
1429
1430         sb->sb_csum = calc_sb_1_csum(sb);
1431 }
1432
1433 static unsigned long long
1434 super_1_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
1435 {
1436         struct mdp_superblock_1 *sb;
1437         sector_t max_sectors;
1438         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1439                 return 0; /* component must fit device */
1440         if (rdev->sb_start < rdev->data_offset) {
1441                 /* minor versions 1 and 2; superblock before data */
1442                 max_sectors = rdev->bdev->bd_inode->i_size >> 9;
1443                 max_sectors -= rdev->data_offset;
1444                 if (!num_sectors || num_sectors > max_sectors)
1445                         num_sectors = max_sectors;
1446         } else if (rdev->mddev->bitmap_offset) {
1447                 /* minor version 0 with bitmap we can't move */
1448                 return 0;
1449         } else {
1450                 /* minor version 0; superblock after data */
1451                 sector_t sb_start;
1452                 sb_start = (rdev->bdev->bd_inode->i_size >> 9) - 8*2;
1453                 sb_start &= ~(sector_t)(4*2 - 1);
1454                 max_sectors = rdev->sectors + sb_start - rdev->sb_start;
1455                 if (!num_sectors || num_sectors > max_sectors)
1456                         num_sectors = max_sectors;
1457                 rdev->sb_start = sb_start;
1458         }
1459         sb = (struct mdp_superblock_1 *) page_address(rdev->sb_page);
1460         sb->data_size = cpu_to_le64(num_sectors);
1461         sb->super_offset = rdev->sb_start;
1462         sb->sb_csum = calc_sb_1_csum(sb);
1463         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1464                        rdev->sb_page);
1465         md_super_wait(rdev->mddev);
1466         return num_sectors / 2; /* kB for sysfs */
1467 }
1468
1469 static struct super_type super_types[] = {
1470         [0] = {
1471                 .name   = "0.90.0",
1472                 .owner  = THIS_MODULE,
1473                 .load_super         = super_90_load,
1474                 .validate_super     = super_90_validate,
1475                 .sync_super         = super_90_sync,
1476                 .rdev_size_change   = super_90_rdev_size_change,
1477         },
1478         [1] = {
1479                 .name   = "md-1",
1480                 .owner  = THIS_MODULE,
1481                 .load_super         = super_1_load,
1482                 .validate_super     = super_1_validate,
1483                 .sync_super         = super_1_sync,
1484                 .rdev_size_change   = super_1_rdev_size_change,
1485         },
1486 };
1487
1488 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1489 {
1490         mdk_rdev_t *rdev, *rdev2;
1491
1492         rcu_read_lock();
1493         rdev_for_each_rcu(rdev, mddev1)
1494                 rdev_for_each_rcu(rdev2, mddev2)
1495                         if (rdev->bdev->bd_contains ==
1496                             rdev2->bdev->bd_contains) {
1497                                 rcu_read_unlock();
1498                                 return 1;
1499                         }
1500         rcu_read_unlock();
1501         return 0;
1502 }
1503
1504 static LIST_HEAD(pending_raid_disks);
1505
1506 static void md_integrity_check(mdk_rdev_t *rdev, mddev_t *mddev)
1507 {
1508         struct mdk_personality *pers = mddev->pers;
1509         struct gendisk *disk = mddev->gendisk;
1510         struct blk_integrity *bi_rdev = bdev_get_integrity(rdev->bdev);
1511         struct blk_integrity *bi_mddev = blk_get_integrity(disk);
1512
1513         /* Data integrity passthrough not supported on RAID 4, 5 and 6 */
1514         if (pers && pers->level >= 4 && pers->level <= 6)
1515                 return;
1516
1517         /* If rdev is integrity capable, register profile for mddev */
1518         if (!bi_mddev && bi_rdev) {
1519                 if (blk_integrity_register(disk, bi_rdev))
1520                         printk(KERN_ERR "%s: %s Could not register integrity!\n",
1521                                __func__, disk->disk_name);
1522                 else
1523                         printk(KERN_NOTICE "Enabling data integrity on %s\n",
1524                                disk->disk_name);
1525                 return;
1526         }
1527
1528         /* Check that mddev and rdev have matching profiles */
1529         if (blk_integrity_compare(disk, rdev->bdev->bd_disk) < 0) {
1530                 printk(KERN_ERR "%s: %s/%s integrity mismatch!\n", __func__,
1531                        disk->disk_name, rdev->bdev->bd_disk->disk_name);
1532                 printk(KERN_NOTICE "Disabling data integrity on %s\n",
1533                        disk->disk_name);
1534                 blk_integrity_unregister(disk);
1535         }
1536 }
1537
1538 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1539 {
1540         char b[BDEVNAME_SIZE];
1541         struct kobject *ko;
1542         char *s;
1543         int err;
1544
1545         if (rdev->mddev) {
1546                 MD_BUG();
1547                 return -EINVAL;
1548         }
1549
1550         /* prevent duplicates */
1551         if (find_rdev(mddev, rdev->bdev->bd_dev))
1552                 return -EEXIST;
1553
1554         /* make sure rdev->sectors exceeds mddev->dev_sectors */
1555         if (rdev->sectors && (mddev->dev_sectors == 0 ||
1556                         rdev->sectors < mddev->dev_sectors)) {
1557                 if (mddev->pers) {
1558                         /* Cannot change size, so fail
1559                          * If mddev->level <= 0, then we don't care
1560                          * about aligning sizes (e.g. linear)
1561                          */
1562                         if (mddev->level > 0)
1563                                 return -ENOSPC;
1564                 } else
1565                         mddev->dev_sectors = rdev->sectors;
1566         }
1567
1568         /* Verify rdev->desc_nr is unique.
1569          * If it is -1, assign a free number, else
1570          * check number is not in use
1571          */
1572         if (rdev->desc_nr < 0) {
1573                 int choice = 0;
1574                 if (mddev->pers) choice = mddev->raid_disks;
1575                 while (find_rdev_nr(mddev, choice))
1576                         choice++;
1577                 rdev->desc_nr = choice;
1578         } else {
1579                 if (find_rdev_nr(mddev, rdev->desc_nr))
1580                         return -EBUSY;
1581         }
1582         if (mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
1583                 printk(KERN_WARNING "md: %s: array is limited to %d devices\n",
1584                        mdname(mddev), mddev->max_disks);
1585                 return -EBUSY;
1586         }
1587         bdevname(rdev->bdev,b);
1588         while ( (s=strchr(b, '/')) != NULL)
1589                 *s = '!';
1590
1591         rdev->mddev = mddev;
1592         printk(KERN_INFO "md: bind<%s>\n", b);
1593
1594         if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
1595                 goto fail;
1596
1597         ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
1598         if ((err = sysfs_create_link(&rdev->kobj, ko, "block"))) {
1599                 kobject_del(&rdev->kobj);
1600                 goto fail;
1601         }
1602         rdev->sysfs_state = sysfs_get_dirent(rdev->kobj.sd, "state");
1603
1604         list_add_rcu(&rdev->same_set, &mddev->disks);
1605         bd_claim_by_disk(rdev->bdev, rdev->bdev->bd_holder, mddev->gendisk);
1606
1607         /* May as well allow recovery to be retried once */
1608         mddev->recovery_disabled = 0;
1609
1610         md_integrity_check(rdev, mddev);
1611         return 0;
1612
1613  fail:
1614         printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
1615                b, mdname(mddev));
1616         return err;
1617 }
1618
1619 static void md_delayed_delete(struct work_struct *ws)
1620 {
1621         mdk_rdev_t *rdev = container_of(ws, mdk_rdev_t, del_work);
1622         kobject_del(&rdev->kobj);
1623         kobject_put(&rdev->kobj);
1624 }
1625
1626 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1627 {
1628         char b[BDEVNAME_SIZE];
1629         if (!rdev->mddev) {
1630                 MD_BUG();
1631                 return;
1632         }
1633         bd_release_from_disk(rdev->bdev, rdev->mddev->gendisk);
1634         list_del_rcu(&rdev->same_set);
1635         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1636         rdev->mddev = NULL;
1637         sysfs_remove_link(&rdev->kobj, "block");
1638         sysfs_put(rdev->sysfs_state);
1639         rdev->sysfs_state = NULL;
1640         /* We need to delay this, otherwise we can deadlock when
1641          * writing to 'remove' to "dev/state".  We also need
1642          * to delay it due to rcu usage.
1643          */
1644         synchronize_rcu();
1645         INIT_WORK(&rdev->del_work, md_delayed_delete);
1646         kobject_get(&rdev->kobj);
1647         schedule_work(&rdev->del_work);
1648 }
1649
1650 /*
1651  * prevent the device from being mounted, repartitioned or
1652  * otherwise reused by a RAID array (or any other kernel
1653  * subsystem), by bd_claiming the device.
1654  */
1655 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev, int shared)
1656 {
1657         int err = 0;
1658         struct block_device *bdev;
1659         char b[BDEVNAME_SIZE];
1660
1661         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1662         if (IS_ERR(bdev)) {
1663                 printk(KERN_ERR "md: could not open %s.\n",
1664                         __bdevname(dev, b));
1665                 return PTR_ERR(bdev);
1666         }
1667         err = bd_claim(bdev, shared ? (mdk_rdev_t *)lock_rdev : rdev);
1668         if (err) {
1669                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1670                         bdevname(bdev, b));
1671                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
1672                 return err;
1673         }
1674         if (!shared)
1675                 set_bit(AllReserved, &rdev->flags);
1676         rdev->bdev = bdev;
1677         return err;
1678 }
1679
1680 static void unlock_rdev(mdk_rdev_t *rdev)
1681 {
1682         struct block_device *bdev = rdev->bdev;
1683         rdev->bdev = NULL;
1684         if (!bdev)
1685                 MD_BUG();
1686         bd_release(bdev);
1687         blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
1688 }
1689
1690 void md_autodetect_dev(dev_t dev);
1691
1692 static void export_rdev(mdk_rdev_t * rdev)
1693 {
1694         char b[BDEVNAME_SIZE];
1695         printk(KERN_INFO "md: export_rdev(%s)\n",
1696                 bdevname(rdev->bdev,b));
1697         if (rdev->mddev)
1698                 MD_BUG();
1699         free_disk_sb(rdev);
1700 #ifndef MODULE
1701         if (test_bit(AutoDetected, &rdev->flags))
1702                 md_autodetect_dev(rdev->bdev->bd_dev);
1703 #endif
1704         unlock_rdev(rdev);
1705         kobject_put(&rdev->kobj);
1706 }
1707
1708 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1709 {
1710         unbind_rdev_from_array(rdev);
1711         export_rdev(rdev);
1712 }
1713
1714 static void export_array(mddev_t *mddev)
1715 {
1716         mdk_rdev_t *rdev, *tmp;
1717
1718         rdev_for_each(rdev, tmp, mddev) {
1719                 if (!rdev->mddev) {
1720                         MD_BUG();
1721                         continue;
1722                 }
1723                 kick_rdev_from_array(rdev);
1724         }
1725         if (!list_empty(&mddev->disks))
1726                 MD_BUG();
1727         mddev->raid_disks = 0;
1728         mddev->major_version = 0;
1729 }
1730
1731 static void print_desc(mdp_disk_t *desc)
1732 {
1733         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1734                 desc->major,desc->minor,desc->raid_disk,desc->state);
1735 }
1736
1737 static void print_sb_90(mdp_super_t *sb)
1738 {
1739         int i;
1740
1741         printk(KERN_INFO 
1742                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1743                 sb->major_version, sb->minor_version, sb->patch_version,
1744                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1745                 sb->ctime);
1746         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1747                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1748                 sb->md_minor, sb->layout, sb->chunk_size);
1749         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1750                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1751                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1752                 sb->failed_disks, sb->spare_disks,
1753                 sb->sb_csum, (unsigned long)sb->events_lo);
1754
1755         printk(KERN_INFO);
1756         for (i = 0; i < MD_SB_DISKS; i++) {
1757                 mdp_disk_t *desc;
1758
1759                 desc = sb->disks + i;
1760                 if (desc->number || desc->major || desc->minor ||
1761                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1762                         printk("     D %2d: ", i);
1763                         print_desc(desc);
1764                 }
1765         }
1766         printk(KERN_INFO "md:     THIS: ");
1767         print_desc(&sb->this_disk);
1768 }
1769
1770 static void print_sb_1(struct mdp_superblock_1 *sb)
1771 {
1772         __u8 *uuid;
1773
1774         uuid = sb->set_uuid;
1775         printk(KERN_INFO "md:  SB: (V:%u) (F:0x%08x) Array-ID:<%02x%02x%02x%02x"
1776                         ":%02x%02x:%02x%02x:%02x%02x:%02x%02x%02x%02x%02x%02x>\n"
1777                KERN_INFO "md:    Name: \"%s\" CT:%llu\n",
1778                 le32_to_cpu(sb->major_version),
1779                 le32_to_cpu(sb->feature_map),
1780                 uuid[0], uuid[1], uuid[2], uuid[3],
1781                 uuid[4], uuid[5], uuid[6], uuid[7],
1782                 uuid[8], uuid[9], uuid[10], uuid[11],
1783                 uuid[12], uuid[13], uuid[14], uuid[15],
1784                 sb->set_name,
1785                 (unsigned long long)le64_to_cpu(sb->ctime)
1786                        & MD_SUPERBLOCK_1_TIME_SEC_MASK);
1787
1788         uuid = sb->device_uuid;
1789         printk(KERN_INFO "md:       L%u SZ%llu RD:%u LO:%u CS:%u DO:%llu DS:%llu SO:%llu"
1790                         " RO:%llu\n"
1791                KERN_INFO "md:     Dev:%08x UUID: %02x%02x%02x%02x:%02x%02x:%02x%02x:%02x%02x"
1792                         ":%02x%02x%02x%02x%02x%02x\n"
1793                KERN_INFO "md:       (F:0x%08x) UT:%llu Events:%llu ResyncOffset:%llu CSUM:0x%08x\n"
1794                KERN_INFO "md:         (MaxDev:%u) \n",
1795                 le32_to_cpu(sb->level),
1796                 (unsigned long long)le64_to_cpu(sb->size),
1797                 le32_to_cpu(sb->raid_disks),
1798                 le32_to_cpu(sb->layout),
1799                 le32_to_cpu(sb->chunksize),
1800                 (unsigned long long)le64_to_cpu(sb->data_offset),
1801                 (unsigned long long)le64_to_cpu(sb->data_size),
1802                 (unsigned long long)le64_to_cpu(sb->super_offset),
1803                 (unsigned long long)le64_to_cpu(sb->recovery_offset),
1804                 le32_to_cpu(sb->dev_number),
1805                 uuid[0], uuid[1], uuid[2], uuid[3],
1806                 uuid[4], uuid[5], uuid[6], uuid[7],
1807                 uuid[8], uuid[9], uuid[10], uuid[11],
1808                 uuid[12], uuid[13], uuid[14], uuid[15],
1809                 sb->devflags,
1810                 (unsigned long long)le64_to_cpu(sb->utime) & MD_SUPERBLOCK_1_TIME_SEC_MASK,
1811                 (unsigned long long)le64_to_cpu(sb->events),
1812                 (unsigned long long)le64_to_cpu(sb->resync_offset),
1813                 le32_to_cpu(sb->sb_csum),
1814                 le32_to_cpu(sb->max_dev)
1815                 );
1816 }
1817
1818 static void print_rdev(mdk_rdev_t *rdev, int major_version)
1819 {
1820         char b[BDEVNAME_SIZE];
1821         printk(KERN_INFO "md: rdev %s, Sect:%08llu F:%d S:%d DN:%u\n",
1822                 bdevname(rdev->bdev, b), (unsigned long long)rdev->sectors,
1823                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1824                 rdev->desc_nr);
1825         if (rdev->sb_loaded) {
1826                 printk(KERN_INFO "md: rdev superblock (MJ:%d):\n", major_version);
1827                 switch (major_version) {
1828                 case 0:
1829                         print_sb_90((mdp_super_t*)page_address(rdev->sb_page));
1830                         break;
1831                 case 1:
1832                         print_sb_1((struct mdp_superblock_1 *)page_address(rdev->sb_page));
1833                         break;
1834                 }
1835         } else
1836                 printk(KERN_INFO "md: no rdev superblock!\n");
1837 }
1838
1839 static void md_print_devices(void)
1840 {
1841         struct list_head *tmp;
1842         mdk_rdev_t *rdev;
1843         mddev_t *mddev;
1844         char b[BDEVNAME_SIZE];
1845
1846         printk("\n");
1847         printk("md:     **********************************\n");
1848         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1849         printk("md:     **********************************\n");
1850         for_each_mddev(mddev, tmp) {
1851
1852                 if (mddev->bitmap)
1853                         bitmap_print_sb(mddev->bitmap);
1854                 else
1855                         printk("%s: ", mdname(mddev));
1856                 list_for_each_entry(rdev, &mddev->disks, same_set)
1857                         printk("<%s>", bdevname(rdev->bdev,b));
1858                 printk("\n");
1859
1860                 list_for_each_entry(rdev, &mddev->disks, same_set)
1861                         print_rdev(rdev, mddev->major_version);
1862         }
1863         printk("md:     **********************************\n");
1864         printk("\n");
1865 }
1866
1867
1868 static void sync_sbs(mddev_t * mddev, int nospares)
1869 {
1870         /* Update each superblock (in-memory image), but
1871          * if we are allowed to, skip spares which already
1872          * have the right event counter, or have one earlier
1873          * (which would mean they aren't being marked as dirty
1874          * with the rest of the array)
1875          */
1876         mdk_rdev_t *rdev;
1877
1878         list_for_each_entry(rdev, &mddev->disks, same_set) {
1879                 if (rdev->sb_events == mddev->events ||
1880                     (nospares &&
1881                      rdev->raid_disk < 0 &&
1882                      (rdev->sb_events&1)==0 &&
1883                      rdev->sb_events+1 == mddev->events)) {
1884                         /* Don't update this superblock */
1885                         rdev->sb_loaded = 2;
1886                 } else {
1887                         super_types[mddev->major_version].
1888                                 sync_super(mddev, rdev);
1889                         rdev->sb_loaded = 1;
1890                 }
1891         }
1892 }
1893
1894 static void md_update_sb(mddev_t * mddev, int force_change)
1895 {
1896         mdk_rdev_t *rdev;
1897         int sync_req;
1898         int nospares = 0;
1899
1900         if (mddev->external)
1901                 return;
1902 repeat:
1903         spin_lock_irq(&mddev->write_lock);
1904
1905         set_bit(MD_CHANGE_PENDING, &mddev->flags);
1906         if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
1907                 force_change = 1;
1908         if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
1909                 /* just a clean<-> dirty transition, possibly leave spares alone,
1910                  * though if events isn't the right even/odd, we will have to do
1911                  * spares after all
1912                  */
1913                 nospares = 1;
1914         if (force_change)
1915                 nospares = 0;
1916         if (mddev->degraded)
1917                 /* If the array is degraded, then skipping spares is both
1918                  * dangerous and fairly pointless.
1919                  * Dangerous because a device that was removed from the array
1920                  * might have a event_count that still looks up-to-date,
1921                  * so it can be re-added without a resync.
1922                  * Pointless because if there are any spares to skip,
1923                  * then a recovery will happen and soon that array won't
1924                  * be degraded any more and the spare can go back to sleep then.
1925                  */
1926                 nospares = 0;
1927
1928         sync_req = mddev->in_sync;
1929         mddev->utime = get_seconds();
1930
1931         /* If this is just a dirty<->clean transition, and the array is clean
1932          * and 'events' is odd, we can roll back to the previous clean state */
1933         if (nospares
1934             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
1935             && (mddev->events & 1)
1936             && mddev->events != 1)
1937                 mddev->events--;
1938         else {
1939                 /* otherwise we have to go forward and ... */
1940                 mddev->events ++;
1941                 if (!mddev->in_sync || mddev->recovery_cp != MaxSector) { /* not clean */
1942                         /* .. if the array isn't clean, insist on an odd 'events' */
1943                         if ((mddev->events&1)==0) {
1944                                 mddev->events++;
1945                                 nospares = 0;
1946                         }
1947                 } else {
1948                         /* otherwise insist on an even 'events' (for clean states) */
1949                         if ((mddev->events&1)) {
1950                                 mddev->events++;
1951                                 nospares = 0;
1952                         }
1953                 }
1954         }
1955
1956         if (!mddev->events) {
1957                 /*
1958                  * oops, this 64-bit counter should never wrap.
1959                  * Either we are in around ~1 trillion A.C., assuming
1960                  * 1 reboot per second, or we have a bug:
1961                  */
1962                 MD_BUG();
1963                 mddev->events --;
1964         }
1965
1966         /*
1967          * do not write anything to disk if using
1968          * nonpersistent superblocks
1969          */
1970         if (!mddev->persistent) {
1971                 if (!mddev->external)
1972                         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
1973
1974                 spin_unlock_irq(&mddev->write_lock);
1975                 wake_up(&mddev->sb_wait);
1976                 return;
1977         }
1978         sync_sbs(mddev, nospares);
1979         spin_unlock_irq(&mddev->write_lock);
1980
1981         dprintk(KERN_INFO 
1982                 "md: updating %s RAID superblock on device (in sync %d)\n",
1983                 mdname(mddev),mddev->in_sync);
1984
1985         bitmap_update_sb(mddev->bitmap);
1986         list_for_each_entry(rdev, &mddev->disks, same_set) {
1987                 char b[BDEVNAME_SIZE];
1988                 dprintk(KERN_INFO "md: ");
1989                 if (rdev->sb_loaded != 1)
1990                         continue; /* no noise on spare devices */
1991                 if (test_bit(Faulty, &rdev->flags))
1992                         dprintk("(skipping faulty ");
1993
1994                 dprintk("%s ", bdevname(rdev->bdev,b));
1995                 if (!test_bit(Faulty, &rdev->flags)) {
1996                         md_super_write(mddev,rdev,
1997                                        rdev->sb_start, rdev->sb_size,
1998                                        rdev->sb_page);
1999                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
2000                                 bdevname(rdev->bdev,b),
2001                                 (unsigned long long)rdev->sb_start);
2002                         rdev->sb_events = mddev->events;
2003
2004                 } else
2005                         dprintk(")\n");
2006                 if (mddev->level == LEVEL_MULTIPATH)
2007                         /* only need to write one superblock... */
2008                         break;
2009         }
2010         md_super_wait(mddev);
2011         /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
2012
2013         spin_lock_irq(&mddev->write_lock);
2014         if (mddev->in_sync != sync_req ||
2015             test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
2016                 /* have to write it out again */
2017                 spin_unlock_irq(&mddev->write_lock);
2018                 goto repeat;
2019         }
2020         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2021         spin_unlock_irq(&mddev->write_lock);
2022         wake_up(&mddev->sb_wait);
2023         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2024                 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
2025
2026 }
2027
2028 /* words written to sysfs files may, or may not, be \n terminated.
2029  * We want to accept with case. For this we use cmd_match.
2030  */
2031 static int cmd_match(const char *cmd, const char *str)
2032 {
2033         /* See if cmd, written into a sysfs file, matches
2034          * str.  They must either be the same, or cmd can
2035          * have a trailing newline
2036          */
2037         while (*cmd && *str && *cmd == *str) {
2038                 cmd++;
2039                 str++;
2040         }
2041         if (*cmd == '\n')
2042                 cmd++;
2043         if (*str || *cmd)
2044                 return 0;
2045         return 1;
2046 }
2047
2048 struct rdev_sysfs_entry {
2049         struct attribute attr;
2050         ssize_t (*show)(mdk_rdev_t *, char *);
2051         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
2052 };
2053
2054 static ssize_t
2055 state_show(mdk_rdev_t *rdev, char *page)
2056 {
2057         char *sep = "";
2058         size_t len = 0;
2059
2060         if (test_bit(Faulty, &rdev->flags)) {
2061                 len+= sprintf(page+len, "%sfaulty",sep);
2062                 sep = ",";
2063         }
2064         if (test_bit(In_sync, &rdev->flags)) {
2065                 len += sprintf(page+len, "%sin_sync",sep);
2066                 sep = ",";
2067         }
2068         if (test_bit(WriteMostly, &rdev->flags)) {
2069                 len += sprintf(page+len, "%swrite_mostly",sep);
2070                 sep = ",";
2071         }
2072         if (test_bit(Blocked, &rdev->flags)) {
2073                 len += sprintf(page+len, "%sblocked", sep);
2074                 sep = ",";
2075         }
2076         if (!test_bit(Faulty, &rdev->flags) &&
2077             !test_bit(In_sync, &rdev->flags)) {
2078                 len += sprintf(page+len, "%sspare", sep);
2079                 sep = ",";
2080         }
2081         return len+sprintf(page+len, "\n");
2082 }
2083
2084 static ssize_t
2085 state_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2086 {
2087         /* can write
2088          *  faulty  - simulates and error
2089          *  remove  - disconnects the device
2090          *  writemostly - sets write_mostly
2091          *  -writemostly - clears write_mostly
2092          *  blocked - sets the Blocked flag
2093          *  -blocked - clears the Blocked flag
2094          *  insync - sets Insync providing device isn't active
2095          */
2096         int err = -EINVAL;
2097         if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2098                 md_error(rdev->mddev, rdev);
2099                 err = 0;
2100         } else if (cmd_match(buf, "remove")) {
2101                 if (rdev->raid_disk >= 0)
2102                         err = -EBUSY;
2103                 else {
2104                         mddev_t *mddev = rdev->mddev;
2105                         kick_rdev_from_array(rdev);
2106                         if (mddev->pers)
2107                                 md_update_sb(mddev, 1);
2108                         md_new_event(mddev);
2109                         err = 0;
2110                 }
2111         } else if (cmd_match(buf, "writemostly")) {
2112                 set_bit(WriteMostly, &rdev->flags);
2113                 err = 0;
2114         } else if (cmd_match(buf, "-writemostly")) {
2115                 clear_bit(WriteMostly, &rdev->flags);
2116                 err = 0;
2117         } else if (cmd_match(buf, "blocked")) {
2118                 set_bit(Blocked, &rdev->flags);
2119                 err = 0;
2120         } else if (cmd_match(buf, "-blocked")) {
2121                 clear_bit(Blocked, &rdev->flags);
2122                 wake_up(&rdev->blocked_wait);
2123                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2124                 md_wakeup_thread(rdev->mddev->thread);
2125
2126                 err = 0;
2127         } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
2128                 set_bit(In_sync, &rdev->flags);
2129                 err = 0;
2130         }
2131         if (!err && rdev->sysfs_state)
2132                 sysfs_notify_dirent(rdev->sysfs_state);
2133         return err ? err : len;
2134 }
2135 static struct rdev_sysfs_entry rdev_state =
2136 __ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
2137
2138 static ssize_t
2139 errors_show(mdk_rdev_t *rdev, char *page)
2140 {
2141         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
2142 }
2143
2144 static ssize_t
2145 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2146 {
2147         char *e;
2148         unsigned long n = simple_strtoul(buf, &e, 10);
2149         if (*buf && (*e == 0 || *e == '\n')) {
2150                 atomic_set(&rdev->corrected_errors, n);
2151                 return len;
2152         }
2153         return -EINVAL;
2154 }
2155 static struct rdev_sysfs_entry rdev_errors =
2156 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
2157
2158 static ssize_t
2159 slot_show(mdk_rdev_t *rdev, char *page)
2160 {
2161         if (rdev->raid_disk < 0)
2162                 return sprintf(page, "none\n");
2163         else
2164                 return sprintf(page, "%d\n", rdev->raid_disk);
2165 }
2166
2167 static ssize_t
2168 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2169 {
2170         char *e;
2171         int err;
2172         char nm[20];
2173         int slot = simple_strtoul(buf, &e, 10);
2174         if (strncmp(buf, "none", 4)==0)
2175                 slot = -1;
2176         else if (e==buf || (*e && *e!= '\n'))
2177                 return -EINVAL;
2178         if (rdev->mddev->pers && slot == -1) {
2179                 /* Setting 'slot' on an active array requires also
2180                  * updating the 'rd%d' link, and communicating
2181                  * with the personality with ->hot_*_disk.
2182                  * For now we only support removing
2183                  * failed/spare devices.  This normally happens automatically,
2184                  * but not when the metadata is externally managed.
2185                  */
2186                 if (rdev->raid_disk == -1)
2187                         return -EEXIST;
2188                 /* personality does all needed checks */
2189                 if (rdev->mddev->pers->hot_add_disk == NULL)
2190                         return -EINVAL;
2191                 err = rdev->mddev->pers->
2192                         hot_remove_disk(rdev->mddev, rdev->raid_disk);
2193                 if (err)
2194                         return err;
2195                 sprintf(nm, "rd%d", rdev->raid_disk);
2196                 sysfs_remove_link(&rdev->mddev->kobj, nm);
2197                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2198                 md_wakeup_thread(rdev->mddev->thread);
2199         } else if (rdev->mddev->pers) {
2200                 mdk_rdev_t *rdev2;
2201                 /* Activating a spare .. or possibly reactivating
2202                  * if we ever get bitmaps working here.
2203                  */
2204
2205                 if (rdev->raid_disk != -1)
2206                         return -EBUSY;
2207
2208                 if (rdev->mddev->pers->hot_add_disk == NULL)
2209                         return -EINVAL;
2210
2211                 list_for_each_entry(rdev2, &rdev->mddev->disks, same_set)
2212                         if (rdev2->raid_disk == slot)
2213                                 return -EEXIST;
2214
2215                 rdev->raid_disk = slot;
2216                 if (test_bit(In_sync, &rdev->flags))
2217                         rdev->saved_raid_disk = slot;
2218                 else
2219                         rdev->saved_raid_disk = -1;
2220                 err = rdev->mddev->pers->
2221                         hot_add_disk(rdev->mddev, rdev);
2222                 if (err) {
2223                         rdev->raid_disk = -1;
2224                         return err;
2225                 } else
2226                         sysfs_notify_dirent(rdev->sysfs_state);
2227                 sprintf(nm, "rd%d", rdev->raid_disk);
2228                 if (sysfs_create_link(&rdev->mddev->kobj, &rdev->kobj, nm))
2229                         printk(KERN_WARNING
2230                                "md: cannot register "
2231                                "%s for %s\n",
2232                                nm, mdname(rdev->mddev));
2233
2234                 /* don't wakeup anyone, leave that to userspace. */
2235         } else {
2236                 if (slot >= rdev->mddev->raid_disks)
2237                         return -ENOSPC;
2238                 rdev->raid_disk = slot;
2239                 /* assume it is working */
2240                 clear_bit(Faulty, &rdev->flags);
2241                 clear_bit(WriteMostly, &rdev->flags);
2242                 set_bit(In_sync, &rdev->flags);
2243                 sysfs_notify_dirent(rdev->sysfs_state);
2244         }
2245         return len;
2246 }
2247
2248
2249 static struct rdev_sysfs_entry rdev_slot =
2250 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
2251
2252 static ssize_t
2253 offset_show(mdk_rdev_t *rdev, char *page)
2254 {
2255         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
2256 }
2257
2258 static ssize_t
2259 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2260 {
2261         char *e;
2262         unsigned long long offset = simple_strtoull(buf, &e, 10);
2263         if (e==buf || (*e && *e != '\n'))
2264                 return -EINVAL;
2265         if (rdev->mddev->pers && rdev->raid_disk >= 0)
2266                 return -EBUSY;
2267         if (rdev->sectors && rdev->mddev->external)
2268                 /* Must set offset before size, so overlap checks
2269                  * can be sane */
2270                 return -EBUSY;
2271         rdev->data_offset = offset;
2272         return len;
2273 }
2274
2275 static struct rdev_sysfs_entry rdev_offset =
2276 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
2277
2278 static ssize_t
2279 rdev_size_show(mdk_rdev_t *rdev, char *page)
2280 {
2281         return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
2282 }
2283
2284 static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
2285 {
2286         /* check if two start/length pairs overlap */
2287         if (s1+l1 <= s2)
2288                 return 0;
2289         if (s2+l2 <= s1)
2290                 return 0;
2291         return 1;
2292 }
2293
2294 static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
2295 {
2296         unsigned long long blocks;
2297         sector_t new;
2298
2299         if (strict_strtoull(buf, 10, &blocks) < 0)
2300                 return -EINVAL;
2301
2302         if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
2303                 return -EINVAL; /* sector conversion overflow */
2304
2305         new = blocks * 2;
2306         if (new != blocks * 2)
2307                 return -EINVAL; /* unsigned long long to sector_t overflow */
2308
2309         *sectors = new;
2310         return 0;
2311 }
2312
2313 static ssize_t
2314 rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2315 {
2316         mddev_t *my_mddev = rdev->mddev;
2317         sector_t oldsectors = rdev->sectors;
2318         sector_t sectors;
2319
2320         if (strict_blocks_to_sectors(buf, &sectors) < 0)
2321                 return -EINVAL;
2322         if (my_mddev->pers && rdev->raid_disk >= 0) {
2323                 if (my_mddev->persistent) {
2324                         sectors = super_types[my_mddev->major_version].
2325                                 rdev_size_change(rdev, sectors);
2326                         if (!sectors)
2327                                 return -EBUSY;
2328                 } else if (!sectors)
2329                         sectors = (rdev->bdev->bd_inode->i_size >> 9) -
2330                                 rdev->data_offset;
2331         }
2332         if (sectors < my_mddev->dev_sectors)
2333                 return -EINVAL; /* component must fit device */
2334
2335         rdev->sectors = sectors;
2336         if (sectors > oldsectors && my_mddev->external) {
2337                 /* need to check that all other rdevs with the same ->bdev
2338                  * do not overlap.  We need to unlock the mddev to avoid
2339                  * a deadlock.  We have already changed rdev->sectors, and if
2340                  * we have to change it back, we will have the lock again.
2341                  */
2342                 mddev_t *mddev;
2343                 int overlap = 0;
2344                 struct list_head *tmp;
2345
2346                 mddev_unlock(my_mddev);
2347                 for_each_mddev(mddev, tmp) {
2348                         mdk_rdev_t *rdev2;
2349
2350                         mddev_lock(mddev);
2351                         list_for_each_entry(rdev2, &mddev->disks, same_set)
2352                                 if (test_bit(AllReserved, &rdev2->flags) ||
2353                                     (rdev->bdev == rdev2->bdev &&
2354                                      rdev != rdev2 &&
2355                                      overlaps(rdev->data_offset, rdev->sectors,
2356                                               rdev2->data_offset,
2357                                               rdev2->sectors))) {
2358                                         overlap = 1;
2359                                         break;
2360                                 }
2361                         mddev_unlock(mddev);
2362                         if (overlap) {
2363                                 mddev_put(mddev);
2364                                 break;
2365                         }
2366                 }
2367                 mddev_lock(my_mddev);
2368                 if (overlap) {
2369                         /* Someone else could have slipped in a size
2370                          * change here, but doing so is just silly.
2371                          * We put oldsectors back because we *know* it is
2372                          * safe, and trust userspace not to race with
2373                          * itself
2374                          */
2375                         rdev->sectors = oldsectors;
2376                         return -EBUSY;
2377                 }
2378         }
2379         return len;
2380 }
2381
2382 static struct rdev_sysfs_entry rdev_size =
2383 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
2384
2385 static struct attribute *rdev_default_attrs[] = {
2386         &rdev_state.attr,
2387         &rdev_errors.attr,
2388         &rdev_slot.attr,
2389         &rdev_offset.attr,
2390         &rdev_size.attr,
2391         NULL,
2392 };
2393 static ssize_t
2394 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2395 {
2396         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2397         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2398         mddev_t *mddev = rdev->mddev;
2399         ssize_t rv;
2400
2401         if (!entry->show)
2402                 return -EIO;
2403
2404         rv = mddev ? mddev_lock(mddev) : -EBUSY;
2405         if (!rv) {
2406                 if (rdev->mddev == NULL)
2407                         rv = -EBUSY;
2408                 else
2409                         rv = entry->show(rdev, page);
2410                 mddev_unlock(mddev);
2411         }
2412         return rv;
2413 }
2414
2415 static ssize_t
2416 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
2417               const char *page, size_t length)
2418 {
2419         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2420         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2421         ssize_t rv;
2422         mddev_t *mddev = rdev->mddev;
2423
2424         if (!entry->store)
2425                 return -EIO;
2426         if (!capable(CAP_SYS_ADMIN))
2427                 return -EACCES;
2428         rv = mddev ? mddev_lock(mddev): -EBUSY;
2429         if (!rv) {
2430                 if (rdev->mddev == NULL)
2431                         rv = -EBUSY;
2432                 else
2433                         rv = entry->store(rdev, page, length);
2434                 mddev_unlock(mddev);
2435         }
2436         return rv;
2437 }
2438
2439 static void rdev_free(struct kobject *ko)
2440 {
2441         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
2442         kfree(rdev);
2443 }
2444 static struct sysfs_ops rdev_sysfs_ops = {
2445         .show           = rdev_attr_show,
2446         .store          = rdev_attr_store,
2447 };
2448 static struct kobj_type rdev_ktype = {
2449         .release        = rdev_free,
2450         .sysfs_ops      = &rdev_sysfs_ops,
2451         .default_attrs  = rdev_default_attrs,
2452 };
2453
2454 /*
2455  * Import a device. If 'super_format' >= 0, then sanity check the superblock
2456  *
2457  * mark the device faulty if:
2458  *
2459  *   - the device is nonexistent (zero size)
2460  *   - the device has no valid superblock
2461  *
2462  * a faulty rdev _never_ has rdev->sb set.
2463  */
2464 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
2465 {
2466         char b[BDEVNAME_SIZE];
2467         int err;
2468         mdk_rdev_t *rdev;
2469         sector_t size;
2470
2471         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
2472         if (!rdev) {
2473                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
2474                 return ERR_PTR(-ENOMEM);
2475         }
2476
2477         if ((err = alloc_disk_sb(rdev)))
2478                 goto abort_free;
2479
2480         err = lock_rdev(rdev, newdev, super_format == -2);
2481         if (err)
2482                 goto abort_free;
2483
2484         kobject_init(&rdev->kobj, &rdev_ktype);
2485
2486         rdev->desc_nr = -1;
2487         rdev->saved_raid_disk = -1;
2488         rdev->raid_disk = -1;
2489         rdev->flags = 0;
2490         rdev->data_offset = 0;
2491         rdev->sb_events = 0;
2492         atomic_set(&rdev->nr_pending, 0);
2493         atomic_set(&rdev->read_errors, 0);
2494         atomic_set(&rdev->corrected_errors, 0);
2495
2496         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2497         if (!size) {
2498                 printk(KERN_WARNING 
2499                         "md: %s has zero or unknown size, marking faulty!\n",
2500                         bdevname(rdev->bdev,b));
2501                 err = -EINVAL;
2502                 goto abort_free;
2503         }
2504
2505         if (super_format >= 0) {
2506                 err = super_types[super_format].
2507                         load_super(rdev, NULL, super_minor);
2508                 if (err == -EINVAL) {
2509                         printk(KERN_WARNING
2510                                 "md: %s does not have a valid v%d.%d "
2511                                "superblock, not importing!\n",
2512                                 bdevname(rdev->bdev,b),
2513                                super_format, super_minor);
2514                         goto abort_free;
2515                 }
2516                 if (err < 0) {
2517                         printk(KERN_WARNING 
2518                                 "md: could not read %s's sb, not importing!\n",
2519                                 bdevname(rdev->bdev,b));
2520                         goto abort_free;
2521                 }
2522         }
2523
2524         INIT_LIST_HEAD(&rdev->same_set);
2525         init_waitqueue_head(&rdev->blocked_wait);
2526
2527         return rdev;
2528
2529 abort_free:
2530         if (rdev->sb_page) {
2531                 if (rdev->bdev)
2532                         unlock_rdev(rdev);
2533                 free_disk_sb(rdev);
2534         }
2535         kfree(rdev);
2536         return ERR_PTR(err);
2537 }
2538
2539 /*
2540  * Check a full RAID array for plausibility
2541  */
2542
2543
2544 static void analyze_sbs(mddev_t * mddev)
2545 {
2546         int i;
2547         mdk_rdev_t *rdev, *freshest, *tmp;
2548         char b[BDEVNAME_SIZE];
2549
2550         freshest = NULL;
2551         rdev_for_each(rdev, tmp, mddev)
2552                 switch (super_types[mddev->major_version].
2553                         load_super(rdev, freshest, mddev->minor_version)) {
2554                 case 1:
2555                         freshest = rdev;
2556                         break;
2557                 case 0:
2558                         break;
2559                 default:
2560                         printk( KERN_ERR \
2561                                 "md: fatal superblock inconsistency in %s"
2562                                 " -- removing from array\n", 
2563                                 bdevname(rdev->bdev,b));
2564                         kick_rdev_from_array(rdev);
2565                 }
2566
2567
2568         super_types[mddev->major_version].
2569                 validate_super(mddev, freshest);
2570
2571         i = 0;
2572         rdev_for_each(rdev, tmp, mddev) {
2573                 if (rdev->desc_nr >= mddev->max_disks ||
2574                     i > mddev->max_disks) {
2575                         printk(KERN_WARNING
2576                                "md: %s: %s: only %d devices permitted\n",
2577                                mdname(mddev), bdevname(rdev->bdev, b),
2578                                mddev->max_disks);
2579                         kick_rdev_from_array(rdev);
2580                         continue;
2581                 }
2582                 if (rdev != freshest)
2583                         if (super_types[mddev->major_version].
2584                             validate_super(mddev, rdev)) {
2585                                 printk(KERN_WARNING "md: kicking non-fresh %s"
2586                                         " from array!\n",
2587                                         bdevname(rdev->bdev,b));
2588                                 kick_rdev_from_array(rdev);
2589                                 continue;
2590                         }
2591                 if (mddev->level == LEVEL_MULTIPATH) {
2592                         rdev->desc_nr = i++;
2593                         rdev->raid_disk = rdev->desc_nr;
2594                         set_bit(In_sync, &rdev->flags);
2595                 } else if (rdev->raid_disk >= mddev->raid_disks) {
2596                         rdev->raid_disk = -1;
2597                         clear_bit(In_sync, &rdev->flags);
2598                 }
2599         }
2600
2601
2602
2603         if (mddev->recovery_cp != MaxSector &&
2604             mddev->level >= 1)
2605                 printk(KERN_ERR "md: %s: raid array is not clean"
2606                        " -- starting background reconstruction\n",
2607                        mdname(mddev));
2608
2609 }
2610
2611 static void md_safemode_timeout(unsigned long data);
2612
2613 static ssize_t
2614 safe_delay_show(mddev_t *mddev, char *page)
2615 {
2616         int msec = (mddev->safemode_delay*1000)/HZ;
2617         return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
2618 }
2619 static ssize_t
2620 safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
2621 {
2622         int scale=1;
2623         int dot=0;
2624         int i;
2625         unsigned long msec;
2626         char buf[30];
2627
2628         /* remove a period, and count digits after it */
2629         if (len >= sizeof(buf))
2630                 return -EINVAL;
2631         strlcpy(buf, cbuf, sizeof(buf));
2632         for (i=0; i<len; i++) {
2633                 if (dot) {
2634                         if (isdigit(buf[i])) {
2635                                 buf[i-1] = buf[i];
2636                                 scale *= 10;
2637                         }
2638                         buf[i] = 0;
2639                 } else if (buf[i] == '.') {
2640                         dot=1;
2641                         buf[i] = 0;
2642                 }
2643         }
2644         if (strict_strtoul(buf, 10, &msec) < 0)
2645                 return -EINVAL;
2646         msec = (msec * 1000) / scale;
2647         if (msec == 0)
2648                 mddev->safemode_delay = 0;
2649         else {
2650                 unsigned long old_delay = mddev->safemode_delay;
2651                 mddev->safemode_delay = (msec*HZ)/1000;
2652                 if (mddev->safemode_delay == 0)
2653                         mddev->safemode_delay = 1;
2654                 if (mddev->safemode_delay < old_delay)
2655                         md_safemode_timeout((unsigned long)mddev);
2656         }
2657         return len;
2658 }
2659 static struct md_sysfs_entry md_safe_delay =
2660 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
2661
2662 static ssize_t
2663 level_show(mddev_t *mddev, char *page)
2664 {
2665         struct mdk_personality *p = mddev->pers;
2666         if (p)
2667                 return sprintf(page, "%s\n", p->name);
2668         else if (mddev->clevel[0])
2669                 return sprintf(page, "%s\n", mddev->clevel);
2670         else if (mddev->level != LEVEL_NONE)
2671                 return sprintf(page, "%d\n", mddev->level);
2672         else
2673                 return 0;
2674 }
2675
2676 static ssize_t
2677 level_store(mddev_t *mddev, const char *buf, size_t len)
2678 {
2679         char level[16];
2680         ssize_t rv = len;
2681         struct mdk_personality *pers;
2682         void *priv;
2683
2684         if (mddev->pers == NULL) {
2685                 if (len == 0)
2686                         return 0;
2687                 if (len >= sizeof(mddev->clevel))
2688                         return -ENOSPC;
2689                 strncpy(mddev->clevel, buf, len);
2690                 if (mddev->clevel[len-1] == '\n')
2691                         len--;
2692                 mddev->clevel[len] = 0;
2693                 mddev->level = LEVEL_NONE;
2694                 return rv;
2695         }
2696
2697         /* request to change the personality.  Need to ensure:
2698          *  - array is not engaged in resync/recovery/reshape
2699          *  - old personality can be suspended
2700          *  - new personality will access other array.
2701          */
2702
2703         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
2704                 return -EBUSY;
2705
2706         if (!mddev->pers->quiesce) {
2707                 printk(KERN_WARNING "md: %s: %s does not support online personality change\n",
2708                        mdname(mddev), mddev->pers->name);
2709                 return -EINVAL;
2710         }
2711
2712         /* Now find the new personality */
2713         if (len == 0 || len >= sizeof(level))
2714                 return -EINVAL;
2715         strncpy(level, buf, len);
2716         if (level[len-1] == '\n')
2717                 len--;
2718         level[len] = 0;
2719
2720         request_module("md-%s", level);
2721         spin_lock(&pers_lock);
2722         pers = find_pers(LEVEL_NONE, level);
2723         if (!pers || !try_module_get(pers->owner)) {
2724                 spin_unlock(&pers_lock);
2725                 printk(KERN_WARNING "md: personality %s not loaded\n", level);
2726                 return -EINVAL;
2727         }
2728         spin_unlock(&pers_lock);
2729
2730         if (pers == mddev->pers) {
2731                 /* Nothing to do! */
2732                 module_put(pers->owner);
2733                 return rv;
2734         }
2735         if (!pers->takeover) {
2736                 module_put(pers->owner);
2737                 printk(KERN_WARNING "md: %s: %s does not support personality takeover\n",
2738                        mdname(mddev), level);
2739                 return -EINVAL;
2740         }
2741
2742         /* ->takeover must set new_* and/or delta_disks
2743          * if it succeeds, and may set them when it fails.
2744          */
2745         priv = pers->takeover(mddev);
2746         if (IS_ERR(priv)) {
2747                 mddev->new_level = mddev->level;
2748                 mddev->new_layout = mddev->layout;
2749                 mddev->new_chunk = mddev->chunk_size;
2750                 mddev->raid_disks -= mddev->delta_disks;
2751                 mddev->delta_disks = 0;
2752                 module_put(pers->owner);
2753                 printk(KERN_WARNING "md: %s: %s would not accept array\n",
2754                        mdname(mddev), level);
2755                 return PTR_ERR(priv);
2756         }
2757
2758         /* Looks like we have a winner */
2759         mddev_suspend(mddev);
2760         mddev->pers->stop(mddev);
2761         module_put(mddev->pers->owner);
2762         mddev->pers = pers;
2763         mddev->private = priv;
2764         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
2765         mddev->level = mddev->new_level;
2766         mddev->layout = mddev->new_layout;
2767         mddev->chunk_size = mddev->new_chunk;
2768         mddev->delta_disks = 0;
2769         pers->run(mddev);
2770         mddev_resume(mddev);
2771         set_bit(MD_CHANGE_DEVS, &mddev->flags);
2772         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2773         md_wakeup_thread(mddev->thread);
2774         return rv;
2775 }
2776
2777 static struct md_sysfs_entry md_level =
2778 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
2779
2780
2781 static ssize_t
2782 layout_show(mddev_t *mddev, char *page)
2783 {
2784         /* just a number, not meaningful for all levels */
2785         if (mddev->reshape_position != MaxSector &&
2786             mddev->layout != mddev->new_layout)
2787                 return sprintf(page, "%d (%d)\n",
2788                                mddev->new_layout, mddev->layout);
2789         return sprintf(page, "%d\n", mddev->layout);
2790 }
2791
2792 static ssize_t
2793 layout_store(mddev_t *mddev, const char *buf, size_t len)
2794 {
2795         char *e;
2796         unsigned long n = simple_strtoul(buf, &e, 10);
2797
2798         if (!*buf || (*e && *e != '\n'))
2799                 return -EINVAL;
2800
2801         if (mddev->pers) {
2802                 int err;
2803                 if (mddev->pers->reconfig == NULL)
2804                         return -EBUSY;
2805                 err = mddev->pers->reconfig(mddev, n, -1);
2806                 if (err)
2807                         return err;
2808         } else {
2809                 mddev->new_layout = n;
2810                 if (mddev->reshape_position == MaxSector)
2811                         mddev->layout = n;
2812         }
2813         return len;
2814 }
2815 static struct md_sysfs_entry md_layout =
2816 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
2817
2818
2819 static ssize_t
2820 raid_disks_show(mddev_t *mddev, char *page)
2821 {
2822         if (mddev->raid_disks == 0)
2823                 return 0;
2824         if (mddev->reshape_position != MaxSector &&
2825             mddev->delta_disks != 0)
2826                 return sprintf(page, "%d (%d)\n", mddev->raid_disks,
2827                                mddev->raid_disks - mddev->delta_disks);
2828         return sprintf(page, "%d\n", mddev->raid_disks);
2829 }
2830
2831 static int update_raid_disks(mddev_t *mddev, int raid_disks);
2832
2833 static ssize_t
2834 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
2835 {
2836         char *e;
2837         int rv = 0;
2838         unsigned long n = simple_strtoul(buf, &e, 10);
2839
2840         if (!*buf || (*e && *e != '\n'))
2841                 return -EINVAL;
2842
2843         if (mddev->pers)
2844                 rv = update_raid_disks(mddev, n);
2845         else if (mddev->reshape_position != MaxSector) {
2846                 int olddisks = mddev->raid_disks - mddev->delta_disks;
2847                 mddev->delta_disks = n - olddisks;
2848                 mddev->raid_disks = n;
2849         } else
2850                 mddev->raid_disks = n;
2851         return rv ? rv : len;
2852 }
2853 static struct md_sysfs_entry md_raid_disks =
2854 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
2855
2856 static ssize_t
2857 chunk_size_show(mddev_t *mddev, char *page)
2858 {
2859         if (mddev->reshape_position != MaxSector &&
2860             mddev->chunk_size != mddev->new_chunk)
2861                 return sprintf(page, "%d (%d)\n", mddev->new_chunk,
2862                                mddev->chunk_size);
2863         return sprintf(page, "%d\n", mddev->chunk_size);
2864 }
2865
2866 static ssize_t
2867 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
2868 {
2869         char *e;
2870         unsigned long n = simple_strtoul(buf, &e, 10);
2871
2872         if (!*buf || (*e && *e != '\n'))
2873                 return -EINVAL;
2874
2875         if (mddev->pers) {
2876                 int err;
2877                 if (mddev->pers->reconfig == NULL)
2878                         return -EBUSY;
2879                 err = mddev->pers->reconfig(mddev, -1, n);
2880                 if (err)
2881                         return err;
2882         } else {
2883                 mddev->new_chunk = n;
2884                 if (mddev->reshape_position == MaxSector)
2885                         mddev->chunk_size = n;
2886         }
2887         return len;
2888 }
2889 static struct md_sysfs_entry md_chunk_size =
2890 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
2891
2892 static ssize_t
2893 resync_start_show(mddev_t *mddev, char *page)
2894 {
2895         if (mddev->recovery_cp == MaxSector)
2896                 return sprintf(page, "none\n");
2897         return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
2898 }
2899
2900 static ssize_t
2901 resync_start_store(mddev_t *mddev, const char *buf, size_t len)
2902 {
2903         char *e;
2904         unsigned long long n = simple_strtoull(buf, &e, 10);
2905
2906         if (mddev->pers)
2907                 return -EBUSY;
2908         if (!*buf || (*e && *e != '\n'))
2909                 return -EINVAL;
2910
2911         mddev->recovery_cp = n;
2912         return len;
2913 }
2914 static struct md_sysfs_entry md_resync_start =
2915 __ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
2916
2917 /*
2918  * The array state can be:
2919  *
2920  * clear
2921  *     No devices, no size, no level
2922  *     Equivalent to STOP_ARRAY ioctl
2923  * inactive
2924  *     May have some settings, but array is not active
2925  *        all IO results in error
2926  *     When written, doesn't tear down array, but just stops it
2927  * suspended (not supported yet)
2928  *     All IO requests will block. The array can be reconfigured.
2929  *     Writing this, if accepted, will block until array is quiescent
2930  * readonly
2931  *     no resync can happen.  no superblocks get written.
2932  *     write requests fail
2933  * read-auto
2934  *     like readonly, but behaves like 'clean' on a write request.
2935  *
2936  * clean - no pending writes, but otherwise active.
2937  *     When written to inactive array, starts without resync
2938  *     If a write request arrives then
2939  *       if metadata is known, mark 'dirty' and switch to 'active'.
2940  *       if not known, block and switch to write-pending
2941  *     If written to an active array that has pending writes, then fails.
2942  * active
2943  *     fully active: IO and resync can be happening.
2944  *     When written to inactive array, starts with resync
2945  *
2946  * write-pending
2947  *     clean, but writes are blocked waiting for 'active' to be written.
2948  *
2949  * active-idle
2950  *     like active, but no writes have been seen for a while (100msec).
2951  *
2952  */
2953 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
2954                    write_pending, active_idle, bad_word};
2955 static char *array_states[] = {
2956         "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
2957         "write-pending", "active-idle", NULL };
2958
2959 static int match_word(const char *word, char **list)
2960 {
2961         int n;
2962         for (n=0; list[n]; n++)
2963                 if (cmd_match(word, list[n]))
2964                         break;
2965         return n;
2966 }
2967
2968 static ssize_t
2969 array_state_show(mddev_t *mddev, char *page)
2970 {
2971         enum array_state st = inactive;
2972
2973         if (mddev->pers)
2974                 switch(mddev->ro) {
2975                 case 1:
2976                         st = readonly;
2977                         break;
2978                 case 2:
2979                         st = read_auto;
2980                         break;
2981                 case 0:
2982                         if (mddev->in_sync)
2983                                 st = clean;
2984                         else if (test_bit(MD_CHANGE_CLEAN, &mddev->flags))
2985                                 st = write_pending;
2986                         else if (mddev->safemode)
2987                                 st = active_idle;
2988                         else
2989                                 st = active;
2990                 }
2991         else {
2992                 if (list_empty(&mddev->disks) &&
2993                     mddev->raid_disks == 0 &&
2994                     mddev->dev_sectors == 0)
2995                         st = clear;
2996                 else
2997                         st = inactive;
2998         }
2999         return sprintf(page, "%s\n", array_states[st]);
3000 }
3001
3002 static int do_md_stop(mddev_t * mddev, int ro, int is_open);
3003 static int do_md_run(mddev_t * mddev);
3004 static int restart_array(mddev_t *mddev);
3005
3006 static ssize_t
3007 array_state_store(mddev_t *mddev, const char *buf, size_t len)
3008 {
3009         int err = -EINVAL;
3010         enum array_state st = match_word(buf, array_states);
3011         switch(st) {
3012         case bad_word:
3013                 break;
3014         case clear:
3015                 /* stopping an active array */
3016                 if (atomic_read(&mddev->openers) > 0)
3017                         return -EBUSY;
3018                 err = do_md_stop(mddev, 0, 0);
3019                 break;
3020         case inactive:
3021                 /* stopping an active array */
3022                 if (mddev->pers) {
3023                         if (atomic_read(&mddev->openers) > 0)
3024                                 return -EBUSY;
3025                         err = do_md_stop(mddev, 2, 0);
3026                 } else
3027                         err = 0; /* already inactive */
3028                 break;
3029         case suspended:
3030                 break; /* not supported yet */
3031         case readonly:
3032                 if (mddev->pers)
3033                         err = do_md_stop(mddev, 1, 0);
3034                 else {
3035                         mddev->ro = 1;
3036                         set_disk_ro(mddev->gendisk, 1);
3037                         err = do_md_run(mddev);
3038                 }
3039                 break;
3040         case read_auto:
3041                 if (mddev->pers) {
3042                         if (mddev->ro == 0)
3043                                 err = do_md_stop(mddev, 1, 0);
3044                         else if (mddev->ro == 1)
3045                                 err = restart_array(mddev);
3046                         if (err == 0) {
3047                                 mddev->ro = 2;
3048                                 set_disk_ro(mddev->gendisk, 0);
3049                         }
3050                 } else {
3051                         mddev->ro = 2;
3052                         err = do_md_run(mddev);
3053                 }
3054                 break;
3055         case clean:
3056                 if (mddev->pers) {
3057                         restart_array(mddev);
3058                         spin_lock_irq(&mddev->write_lock);
3059                         if (atomic_read(&mddev->writes_pending) == 0) {
3060                                 if (mddev->in_sync == 0) {
3061                                         mddev->in_sync = 1;
3062                                         if (mddev->safemode == 1)
3063                                                 mddev->safemode = 0;
3064                                         if (mddev->persistent)
3065                                                 set_bit(MD_CHANGE_CLEAN,
3066                                                         &mddev->flags);
3067                                 }
3068                                 err = 0;
3069                         } else
3070                                 err = -EBUSY;
3071                         spin_unlock_irq(&mddev->write_lock);
3072                 } else
3073                         err = -EINVAL;
3074                 break;
3075         case active:
3076                 if (mddev->pers) {
3077                         restart_array(mddev);
3078                         if (mddev->external)
3079                                 clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
3080                         wake_up(&mddev->sb_wait);
3081                         err = 0;
3082                 } else {
3083                         mddev->ro = 0;
3084                         set_disk_ro(mddev->gendisk, 0);
3085                         err = do_md_run(mddev);
3086                 }
3087                 break;
3088         case write_pending:
3089         case active_idle:
3090                 /* these cannot be set */
3091                 break;
3092         }
3093         if (err)
3094                 return err;
3095         else {
3096                 sysfs_notify_dirent(mddev->sysfs_state);
3097                 return len;
3098         }
3099 }
3100 static struct md_sysfs_entry md_array_state =
3101 __ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
3102
3103 static ssize_t
3104 null_show(mddev_t *mddev, char *page)
3105 {
3106         return -EINVAL;
3107 }
3108
3109 static ssize_t
3110 new_dev_store(mddev_t *mddev, const char *buf, size_t len)
3111 {
3112         /* buf must be %d:%d\n? giving major and minor numbers */
3113         /* The new device is added to the array.
3114          * If the array has a persistent superblock, we read the
3115          * superblock to initialise info and check validity.
3116          * Otherwise, only checking done is that in bind_rdev_to_array,
3117          * which mainly checks size.
3118          */
3119         char *e;
3120         int major = simple_strtoul(buf, &e, 10);
3121         int minor;
3122         dev_t dev;
3123         mdk_rdev_t *rdev;
3124         int err;
3125
3126         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
3127                 return -EINVAL;
3128         minor = simple_strtoul(e+1, &e, 10);
3129         if (*e && *e != '\n')
3130                 return -EINVAL;
3131         dev = MKDEV(major, minor);
3132         if (major != MAJOR(dev) ||
3133             minor != MINOR(dev))
3134                 return -EOVERFLOW;
3135
3136
3137         if (mddev->persistent) {
3138                 rdev = md_import_device(dev, mddev->major_version,
3139                                         mddev->minor_version);
3140                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
3141                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
3142                                                        mdk_rdev_t, same_set);
3143                         err = super_types[mddev->major_version]
3144                                 .load_super(rdev, rdev0, mddev->minor_version);
3145                         if (err < 0)
3146                                 goto out;
3147                 }
3148         } else if (mddev->external)
3149                 rdev = md_import_device(dev, -2, -1);
3150         else
3151                 rdev = md_import_device(dev, -1, -1);
3152
3153         if (IS_ERR(rdev))
3154                 return PTR_ERR(rdev);
3155         err = bind_rdev_to_array(rdev, mddev);
3156  out:
3157         if (err)
3158                 export_rdev(rdev);
3159         return err ? err : len;
3160 }
3161
3162 static struct md_sysfs_entry md_new_device =
3163 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
3164
3165 static ssize_t
3166 bitmap_store(mddev_t *mddev, const char *buf, size_t len)
3167 {
3168         char *end;
3169         unsigned long chunk, end_chunk;
3170
3171         if (!mddev->bitmap)
3172                 goto out;
3173         /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
3174         while (*buf) {
3175                 chunk = end_chunk = simple_strtoul(buf, &end, 0);
3176                 if (buf == end) break;
3177                 if (*end == '-') { /* range */
3178                         buf = end + 1;
3179                         end_chunk = simple_strtoul(buf, &end, 0);
3180                         if (buf == end) break;
3181                 }
3182                 if (*end && !isspace(*end)) break;
3183                 bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
3184                 buf = end;
3185                 while (isspace(*buf)) buf++;
3186         }
3187         bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
3188 out:
3189         return len;
3190 }
3191
3192 static struct md_sysfs_entry md_bitmap =
3193 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
3194
3195 static ssize_t
3196 size_show(mddev_t *mddev, char *page)
3197 {
3198         return sprintf(page, "%llu\n",
3199                 (unsigned long long)mddev->dev_sectors / 2);
3200 }
3201
3202 static int update_size(mddev_t *mddev, sector_t num_sectors);
3203
3204 static ssize_t
3205 size_store(mddev_t *mddev, const char *buf, size_t len)
3206 {
3207         /* If array is inactive, we can reduce the component size, but
3208          * not increase it (except from 0).
3209          * If array is active, we can try an on-line resize
3210          */
3211         sector_t sectors;
3212         int err = strict_blocks_to_sectors(buf, &sectors);
3213
3214         if (err < 0)
3215                 return err;
3216         if (mddev->pers) {
3217                 err = update_size(mddev, sectors);
3218                 md_update_sb(mddev, 1);
3219         } else {
3220                 if (mddev->dev_sectors == 0 ||
3221                     mddev->dev_sectors > sectors)
3222                         mddev->dev_sectors = sectors;
3223                 else
3224                         err = -ENOSPC;
3225         }
3226         return err ? err : len;
3227 }
3228
3229 static struct md_sysfs_entry md_size =
3230 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
3231
3232
3233 /* Metdata version.
3234  * This is one of
3235  *   'none' for arrays with no metadata (good luck...)
3236  *   'external' for arrays with externally managed metadata,
3237  * or N.M for internally known formats
3238  */
3239 static ssize_t
3240 metadata_show(mddev_t *mddev, char *page)
3241 {
3242         if (mddev->persistent)
3243                 return sprintf(page, "%d.%d\n",
3244                                mddev->major_version, mddev->minor_version);
3245         else if (mddev->external)
3246                 return sprintf(page, "external:%s\n", mddev->metadata_type);
3247         else
3248                 return sprintf(page, "none\n");
3249 }
3250
3251 static ssize_t
3252 metadata_store(mddev_t *mddev, const char *buf, size_t len)
3253 {
3254         int major, minor;
3255         char *e;
3256         /* Changing the details of 'external' metadata is
3257          * always permitted.  Otherwise there must be
3258          * no devices attached to the array.
3259          */
3260         if (mddev->external && strncmp(buf, "external:", 9) == 0)
3261                 ;
3262         else if (!list_empty(&mddev->disks))
3263                 return -EBUSY;
3264
3265         if (cmd_match(buf, "none")) {
3266                 mddev->persistent = 0;
3267                 mddev->external = 0;
3268                 mddev->major_version = 0;
3269                 mddev->minor_version = 90;
3270                 return len;
3271         }
3272         if (strncmp(buf, "external:", 9) == 0) {
3273                 size_t namelen = len-9;
3274                 if (namelen >= sizeof(mddev->metadata_type))
3275                         namelen = sizeof(mddev->metadata_type)-1;
3276                 strncpy(mddev->metadata_type, buf+9, namelen);
3277                 mddev->metadata_type[namelen] = 0;
3278                 if (namelen && mddev->metadata_type[namelen-1] == '\n')
3279                         mddev->metadata_type[--namelen] = 0;
3280                 mddev->persistent = 0;
3281                 mddev->external = 1;
3282                 mddev->major_version = 0;
3283                 mddev->minor_version = 90;
3284                 return len;
3285         }
3286         major = simple_strtoul(buf, &e, 10);
3287         if (e==buf || *e != '.')
3288                 return -EINVAL;
3289         buf = e+1;
3290         minor = simple_strtoul(buf, &e, 10);
3291         if (e==buf || (*e && *e != '\n') )
3292                 return -EINVAL;
3293         if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
3294                 return -ENOENT;
3295         mddev->major_version = major;
3296         mddev->minor_version = minor;
3297         mddev->persistent = 1;
3298         mddev->external = 0;
3299         return len;
3300 }
3301
3302 static struct md_sysfs_entry md_metadata =
3303 __ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
3304
3305 static ssize_t
3306 action_show(mddev_t *mddev, char *page)
3307 {
3308         char *type = "idle";
3309         if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3310                 type = "frozen";
3311         else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3312             (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
3313                 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
3314                         type = "reshape";
3315                 else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
3316                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
3317                                 type = "resync";
3318                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
3319                                 type = "check";
3320                         else
3321                                 type = "repair";
3322                 } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
3323                         type = "recover";
3324         }
3325         return sprintf(page, "%s\n", type);
3326 }
3327
3328 static ssize_t
3329 action_store(mddev_t *mddev, const char *page, size_t len)
3330 {
3331         if (!mddev->pers || !mddev->pers->sync_request)
3332                 return -EINVAL;
3333
3334         if (cmd_match(page, "frozen"))
3335                 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3336         else
3337                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3338
3339         if (cmd_match(page, "idle") || cmd_match(page, "frozen")) {
3340                 if (mddev->sync_thread) {
3341                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3342                         md_unregister_thread(mddev->sync_thread);
3343                         mddev->sync_thread = NULL;
3344                         mddev->recovery = 0;
3345                 }
3346         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3347                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3348                 return -EBUSY;
3349         else if (cmd_match(page, "resync"))
3350                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3351         else if (cmd_match(page, "recover")) {
3352                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3353                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3354         } else if (cmd_match(page, "reshape")) {
3355                 int err;
3356                 if (mddev->pers->start_reshape == NULL)
3357                         return -EINVAL;
3358                 err = mddev->pers->start_reshape(mddev);
3359                 if (err)
3360                         return err;
3361                 sysfs_notify(&mddev->kobj, NULL, "degraded");
3362         } else {
3363                 if (cmd_match(page, "check"))
3364                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3365                 else if (!cmd_match(page, "repair"))
3366                         return -EINVAL;
3367                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3368                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3369         }
3370         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3371         md_wakeup_thread(mddev->thread);
3372         sysfs_notify_dirent(mddev->sysfs_action);
3373         return len;
3374 }
3375
3376 static ssize_t
3377 mismatch_cnt_show(mddev_t *mddev, char *page)
3378 {
3379         return sprintf(page, "%llu\n",
3380                        (unsigned long long) mddev->resync_mismatches);
3381 }
3382
3383 static struct md_sysfs_entry md_scan_mode =
3384 __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
3385
3386
3387 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
3388
3389 static ssize_t
3390 sync_min_show(mddev_t *mddev, char *page)
3391 {
3392         return sprintf(page, "%d (%s)\n", speed_min(mddev),
3393                        mddev->sync_speed_min ? "local": "system");
3394 }
3395
3396 static ssize_t
3397 sync_min_store(mddev_t *mddev, const char *buf, size_t len)
3398 {
3399         int min;
3400         char *e;
3401         if (strncmp(buf, "system", 6)==0) {
3402                 mddev->sync_speed_min = 0;
3403                 return len;
3404         }
3405         min = simple_strtoul(buf, &e, 10);
3406         if (buf == e || (*e && *e != '\n') || min <= 0)
3407                 return -EINVAL;
3408         mddev->sync_speed_min = min;
3409         return len;
3410 }
3411
3412 static struct md_sysfs_entry md_sync_min =
3413 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
3414
3415 static ssize_t
3416 sync_max_show(mddev_t *mddev, char *page)
3417 {
3418         return sprintf(page, "%d (%s)\n", speed_max(mddev),
3419                        mddev->sync_speed_max ? "local": "system");
3420 }
3421
3422 static ssize_t
3423 sync_max_store(mddev_t *mddev, const char *buf, size_t len)
3424 {
3425         int max;
3426         char *e;
3427         if (strncmp(buf, "system", 6)==0) {
3428                 mddev->sync_speed_max = 0;
3429                 return len;
3430         }
3431         max = simple_strtoul(buf, &e, 10);
3432         if (buf == e || (*e && *e != '\n') || max <= 0)
3433                 return -EINVAL;
3434         mddev->sync_speed_max = max;
3435         return len;
3436 }
3437
3438 static struct md_sysfs_entry md_sync_max =
3439 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
3440
3441 static ssize_t
3442 degraded_show(mddev_t *mddev, char *page)
3443 {
3444         return sprintf(page, "%d\n", mddev->degraded);
3445 }
3446 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
3447
3448 static ssize_t
3449 sync_force_parallel_show(mddev_t *mddev, char *page)
3450 {
3451         return sprintf(page, "%d\n", mddev->parallel_resync);
3452 }
3453
3454 static ssize_t
3455 sync_force_parallel_store(mddev_t *mddev, const char *buf, size_t len)
3456 {
3457         long n;
3458
3459         if (strict_strtol(buf, 10, &n))
3460                 return -EINVAL;
3461
3462         if (n != 0 && n != 1)
3463                 return -EINVAL;
3464
3465         mddev->parallel_resync = n;
3466
3467         if (mddev->sync_thread)
3468                 wake_up(&resync_wait);
3469
3470         return len;
3471 }
3472
3473 /* force parallel resync, even with shared block devices */
3474 static struct md_sysfs_entry md_sync_force_parallel =
3475 __ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
3476        sync_force_parallel_show, sync_force_parallel_store);
3477
3478 static ssize_t
3479 sync_speed_show(mddev_t *mddev, char *page)
3480 {
3481         unsigned long resync, dt, db;
3482         if (mddev->curr_resync == 0)
3483                 return sprintf(page, "none\n");
3484         resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
3485         dt = (jiffies - mddev->resync_mark) / HZ;
3486         if (!dt) dt++;
3487         db = resync - mddev->resync_mark_cnt;
3488         return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
3489 }
3490
3491 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
3492
3493 static ssize_t
3494 sync_completed_show(mddev_t *mddev, char *page)
3495 {
3496         unsigned long max_sectors, resync;
3497
3498         if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3499                 return sprintf(page, "none\n");
3500
3501         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3502                 max_sectors = mddev->resync_max_sectors;
3503         else
3504                 max_sectors = mddev->dev_sectors;
3505
3506         resync = mddev->curr_resync_completed;
3507         return sprintf(page, "%lu / %lu\n", resync, max_sectors);
3508 }
3509
3510 static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
3511
3512 static ssize_t
3513 min_sync_show(mddev_t *mddev, char *page)
3514 {
3515         return sprintf(page, "%llu\n",
3516                        (unsigned long long)mddev->resync_min);
3517 }
3518 static ssize_t
3519 min_sync_store(mddev_t *mddev, const char *buf, size_t len)
3520 {
3521         unsigned long long min;
3522         if (strict_strtoull(buf, 10, &min))
3523                 return -EINVAL;
3524         if (min > mddev->resync_max)
3525                 return -EINVAL;
3526         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3527                 return -EBUSY;
3528
3529         /* Must be a multiple of chunk_size */
3530         if (mddev->chunk_size) {
3531                 if (min & (sector_t)((mddev->chunk_size>>9)-1))
3532                         return -EINVAL;
3533         }
3534         mddev->resync_min = min;
3535
3536         return len;
3537 }
3538
3539 static struct md_sysfs_entry md_min_sync =
3540 __ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
3541
3542 static ssize_t
3543 max_sync_show(mddev_t *mddev, char *page)
3544 {
3545         if (mddev->resync_max == MaxSector)
3546                 return sprintf(page, "max\n");
3547         else
3548                 return sprintf(page, "%llu\n",
3549                                (unsigned long long)mddev->resync_max);
3550 }
3551 static ssize_t
3552 max_sync_store(mddev_t *mddev, const char *buf, size_t len)
3553 {
3554         if (strncmp(buf, "max", 3) == 0)
3555                 mddev->resync_max = MaxSector;
3556         else {
3557                 unsigned long long max;
3558                 if (strict_strtoull(buf, 10, &max))
3559                         return -EINVAL;
3560                 if (max < mddev->resync_min)
3561                         return -EINVAL;
3562                 if (max < mddev->resync_max &&
3563                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3564                         return -EBUSY;
3565
3566                 /* Must be a multiple of chunk_size */
3567                 if (mddev->chunk_size) {
3568                         if (max & (sector_t)((mddev->chunk_size>>9)-1))
3569                                 return -EINVAL;
3570                 }
3571                 mddev->resync_max = max;
3572         }
3573         wake_up(&mddev->recovery_wait);
3574         return len;
3575 }
3576
3577 static struct md_sysfs_entry md_max_sync =
3578 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
3579
3580 static ssize_t
3581 suspend_lo_show(mddev_t *mddev, char *page)
3582 {
3583         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
3584 }
3585
3586 static ssize_t
3587 suspend_lo_store(mddev_t *mddev, const char *buf, size_t len)
3588 {
3589         char *e;
3590         unsigned long long new = simple_strtoull(buf, &e, 10);
3591
3592         if (mddev->pers->quiesce == NULL)
3593                 return -EINVAL;
3594         if (buf == e || (*e && *e != '\n'))
3595                 return -EINVAL;
3596         if (new >= mddev->suspend_hi ||
3597             (new > mddev->suspend_lo && new < mddev->suspend_hi)) {
3598                 mddev->suspend_lo = new;
3599                 mddev->pers->quiesce(mddev, 2);
3600                 return len;
3601         } else
3602                 return -EINVAL;
3603 }
3604 static struct md_sysfs_entry md_suspend_lo =
3605 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
3606
3607
3608 static ssize_t
3609 suspend_hi_show(mddev_t *mddev, char *page)
3610 {
3611         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
3612 }
3613
3614 static ssize_t
3615 suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
3616 {
3617         char *e;
3618         unsigned long long new = simple_strtoull(buf, &e, 10);
3619
3620         if (mddev->pers->quiesce == NULL)
3621                 return -EINVAL;
3622         if (buf == e || (*e && *e != '\n'))
3623                 return -EINVAL;
3624         if ((new <= mddev->suspend_lo && mddev->suspend_lo >= mddev->suspend_hi) ||
3625             (new > mddev->suspend_lo && new > mddev->suspend_hi)) {
3626                 mddev->suspend_hi = new;
3627                 mddev->pers->quiesce(mddev, 1);
3628                 mddev->pers->quiesce(mddev, 0);
3629                 return len;
3630         } else
3631                 return -EINVAL;
3632 }
3633 static struct md_sysfs_entry md_suspend_hi =
3634 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
3635
3636 static ssize_t
3637 reshape_position_show(mddev_t *mddev, char *page)
3638 {
3639         if (mddev->reshape_position != MaxSector)
3640                 return sprintf(page, "%llu\n",
3641                                (unsigned long long)mddev->reshape_position);
3642         strcpy(page, "none\n");
3643         return 5;
3644 }
3645
3646 static ssize_t
3647 reshape_position_store(mddev_t *mddev, const char *buf, size_t len)
3648 {
3649         char *e;
3650         unsigned long long new = simple_strtoull(buf, &e, 10);
3651         if (mddev->pers)
3652                 return -EBUSY;
3653         if (buf == e || (*e && *e != '\n'))
3654                 return -EINVAL;
3655         mddev->reshape_position = new;
3656         mddev->delta_disks = 0;
3657         mddev->new_level = mddev->level;
3658         mddev->new_layout = mddev->layout;
3659         mddev->new_chunk = mddev->chunk_size;
3660         return len;
3661 }
3662
3663 static struct md_sysfs_entry md_reshape_position =
3664 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
3665        reshape_position_store);
3666
3667 static ssize_t
3668 array_size_show(mddev_t *mddev, char *page)
3669 {
3670         if (mddev->external_size)
3671                 return sprintf(page, "%llu\n",
3672                                (unsigned long long)mddev->array_sectors/2);
3673         else
3674                 return sprintf(page, "default\n");
3675 }
3676
3677 static ssize_t
3678 array_size_store(mddev_t *mddev, const char *buf, size_t len)
3679 {
3680         sector_t sectors;
3681
3682         if (strncmp(buf, "default", 7) == 0) {
3683                 if (mddev->pers)
3684                         sectors = mddev->pers->size(mddev, 0, 0);
3685                 else
3686                         sectors = mddev->array_sectors;
3687
3688                 mddev->external_size = 0;
3689         } else {
3690                 if (strict_blocks_to_sectors(buf, &sectors) < 0)
3691                         return -EINVAL;
3692                 if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
3693                         return -E2BIG;
3694
3695                 mddev->external_size = 1;
3696         }
3697
3698         mddev->array_sectors = sectors;
3699         set_capacity(mddev->gendisk, mddev->array_sectors);
3700         if (mddev->pers) {
3701                 struct block_device *bdev = bdget_disk(mddev->gendisk, 0);
3702
3703                 if (bdev) {
3704                         mutex_lock(&bdev->bd_inode->i_mutex);
3705                         i_size_write(bdev->bd_inode,
3706                                      (loff_t)mddev->array_sectors << 9);
3707                         mutex_unlock(&bdev->bd_inode->i_mutex);
3708                         bdput(bdev);
3709                 }
3710         }
3711
3712         return len;
3713 }
3714
3715 static struct md_sysfs_entry md_array_size =
3716 __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
3717        array_size_store);
3718
3719 static struct attribute *md_default_attrs[] = {
3720         &md_level.attr,
3721         &md_layout.attr,
3722         &md_raid_disks.attr,
3723         &md_chunk_size.attr,
3724         &md_size.attr,
3725         &md_resync_start.attr,
3726         &md_metadata.attr,
3727         &md_new_device.attr,
3728         &md_safe_delay.attr,
3729         &md_array_state.attr,
3730         &md_reshape_position.attr,
3731         &md_array_size.attr,
3732         NULL,
3733 };
3734
3735 static struct attribute *md_redundancy_attrs[] = {
3736         &md_scan_mode.attr,
3737         &md_mismatches.attr,
3738         &md_sync_min.attr,
3739         &md_sync_max.attr,
3740         &md_sync_speed.attr,
3741         &md_sync_force_parallel.attr,
3742         &md_sync_completed.attr,
3743         &md_min_sync.attr,
3744         &md_max_sync.attr,
3745         &md_suspend_lo.attr,
3746         &md_suspend_hi.attr,
3747         &md_bitmap.attr,
3748         &md_degraded.attr,
3749         NULL,
3750 };
3751 static struct attribute_group md_redundancy_group = {
3752         .name = NULL,
3753         .attrs = md_redundancy_attrs,
3754 };
3755
3756
3757 static ssize_t
3758 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3759 {
3760         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3761         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3762         ssize_t rv;
3763
3764         if (!entry->show)
3765                 return -EIO;
3766         rv = mddev_lock(mddev);
3767         if (!rv) {
3768                 rv = entry->show(mddev, page);
3769                 mddev_unlock(mddev);
3770         }
3771         return rv;
3772 }
3773
3774 static ssize_t
3775 md_attr_store(struct kobject *kobj, struct attribute *attr,
3776               const char *page, size_t length)
3777 {
3778         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3779         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3780         ssize_t rv;
3781
3782         if (!entry->store)
3783                 return -EIO;
3784         if (!capable(CAP_SYS_ADMIN))
3785                 return -EACCES;
3786         rv = mddev_lock(mddev);
3787         if (mddev->hold_active == UNTIL_IOCTL)
3788                 mddev->hold_active = 0;
3789         if (!rv) {
3790                 rv = entry->store(mddev, page, length);
3791                 mddev_unlock(mddev);
3792         }
3793         return rv;
3794 }
3795
3796 static void md_free(struct kobject *ko)
3797 {
3798         mddev_t *mddev = container_of(ko, mddev_t, kobj);
3799
3800         if (mddev->sysfs_state)
3801                 sysfs_put(mddev->sysfs_state);
3802
3803         if (mddev->gendisk) {
3804                 del_gendisk(mddev->gendisk);
3805                 put_disk(mddev->gendisk);
3806         }
3807         if (mddev->queue)
3808                 blk_cleanup_queue(mddev->queue);
3809
3810         kfree(mddev);
3811 }
3812
3813 static struct sysfs_ops md_sysfs_ops = {
3814         .show   = md_attr_show,
3815         .store  = md_attr_store,
3816 };
3817 static struct kobj_type md_ktype = {
3818         .release        = md_free,
3819         .sysfs_ops      = &md_sysfs_ops,
3820         .default_attrs  = md_default_attrs,
3821 };
3822
3823 int mdp_major = 0;
3824
3825 static void mddev_delayed_delete(struct work_struct *ws)
3826 {
3827         mddev_t *mddev = container_of(ws, mddev_t, del_work);
3828
3829         if (mddev->private == &md_redundancy_group) {
3830                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
3831                 if (mddev->sysfs_action)
3832                         sysfs_put(mddev->sysfs_action);
3833                 mddev->sysfs_action = NULL;
3834                 mddev->private = NULL;
3835         }
3836         kobject_del(&mddev->kobj);
3837         kobject_put(&mddev->kobj);
3838 }
3839
3840 static int md_alloc(dev_t dev, char *name)
3841 {
3842         static DEFINE_MUTEX(disks_mutex);
3843         mddev_t *mddev = mddev_find(dev);
3844         struct gendisk *disk;
3845         int partitioned;
3846         int shift;
3847         int unit;
3848         int error;
3849
3850         if (!mddev)
3851                 return -ENODEV;
3852
3853         partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
3854         shift = partitioned ? MdpMinorShift : 0;
3855         unit = MINOR(mddev->unit) >> shift;
3856
3857         /* wait for any previous instance if this device
3858          * to be completed removed (mddev_delayed_delete).
3859          */
3860         flush_scheduled_work();
3861
3862         mutex_lock(&disks_mutex);
3863         if (mddev->gendisk) {
3864                 mutex_unlock(&disks_mutex);
3865                 mddev_put(mddev);
3866                 return -EEXIST;
3867         }
3868
3869         if (name) {
3870                 /* Need to ensure that 'name' is not a duplicate.
3871                  */
3872                 mddev_t *mddev2;
3873                 spin_lock(&all_mddevs_lock);
3874
3875                 list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
3876                         if (mddev2->gendisk &&
3877                             strcmp(mddev2->gendisk->disk_name, name) == 0) {
3878                                 spin_unlock(&all_mddevs_lock);
3879                                 return -EEXIST;
3880                         }
3881                 spin_unlock(&all_mddevs_lock);
3882         }
3883
3884         mddev->queue = blk_alloc_queue(GFP_KERNEL);
3885         if (!mddev->queue) {
3886                 mutex_unlock(&disks_mutex);
3887                 mddev_put(mddev);
3888                 return -ENOMEM;
3889         }
3890         mddev->queue->queuedata = mddev;
3891
3892         /* Can be unlocked because the queue is new: no concurrency */
3893         queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, mddev->queue);
3894
3895         blk_queue_make_request(mddev->queue, md_make_request);
3896
3897         disk = alloc_disk(1 << shift);
3898         if (!disk) {
3899                 mutex_unlock(&disks_mutex);
3900                 blk_cleanup_queue(mddev->queue);
3901                 mddev->queue = NULL;
3902                 mddev_put(mddev);
3903                 return -ENOMEM;
3904         }
3905         disk->major = MAJOR(mddev->unit);
3906         disk->first_minor = unit << shift;
3907         if (name)
3908                 strcpy(disk->disk_name, name);
3909         else if (partitioned)
3910                 sprintf(disk->disk_name, "md_d%d", unit);
3911         else
3912                 sprintf(disk->disk_name, "md%d", unit);
3913         disk->fops = &md_fops;
3914         disk->private_data = mddev;
3915         disk->queue = mddev->queue;
3916         /* Allow extended partitions.  This makes the
3917          * 'mdp' device redundant, but we can't really
3918          * remove it now.
3919          */
3920         disk->flags |= GENHD_FL_EXT_DEVT;
3921         add_disk(disk);
3922         mddev->gendisk = disk;
3923         error = kobject_init_and_add(&mddev->kobj, &md_ktype,
3924                                      &disk_to_dev(disk)->kobj, "%s", "md");
3925         mutex_unlock(&disks_mutex);
3926         if (error)
3927                 printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
3928                        disk->disk_name);
3929         else {
3930                 kobject_uevent(&mddev->kobj, KOBJ_ADD);
3931                 mddev->sysfs_state = sysfs_get_dirent(mddev->kobj.sd, "array_state");
3932         }
3933         mddev_put(mddev);
3934         return 0;
3935 }
3936
3937 static struct kobject *md_probe(dev_t dev, int *part, void *data)
3938 {
3939         md_alloc(dev, NULL);
3940         return NULL;
3941 }
3942
3943 static int add_named_array(const char *val, struct kernel_param *kp)
3944 {
3945         /* val must be "md_*" where * is not all digits.
3946          * We allocate an array with a large free minor number, and
3947          * set the name to val.  val must not already be an active name.
3948          */
3949         int len = strlen(val);
3950         char buf[DISK_NAME_LEN];
3951
3952         while (len && val[len-1] == '\n')
3953                 len--;
3954         if (len >= DISK_NAME_LEN)
3955                 return -E2BIG;
3956         strlcpy(buf, val, len+1);
3957         if (strncmp(buf, "md_", 3) != 0)
3958                 return -EINVAL;
3959         return md_alloc(0, buf);
3960 }
3961
3962 static void md_safemode_timeout(unsigned long data)
3963 {
3964         mddev_t *mddev = (mddev_t *) data;
3965
3966         if (!atomic_read(&mddev->writes_pending)) {
3967                 mddev->safemode = 1;
3968                 if (mddev->external)
3969                         sysfs_notify_dirent(mddev->sysfs_state);
3970         }
3971         md_wakeup_thread(mddev->thread);
3972 }
3973
3974 static int start_dirty_degraded;
3975
3976 static int do_md_run(mddev_t * mddev)
3977 {
3978         int err;
3979         int chunk_size;
3980         mdk_rdev_t *rdev;
3981         struct gendisk *disk;
3982         struct mdk_personality *pers;
3983         char b[BDEVNAME_SIZE];
3984
3985         if (list_empty(&mddev->disks))
3986                 /* cannot run an array with no devices.. */
3987                 return -EINVAL;
3988
3989         if (mddev->pers)
3990                 return -EBUSY;
3991
3992         /*
3993          * Analyze all RAID superblock(s)
3994          */
3995         if (!mddev->raid_disks) {
3996                 if (!mddev->persistent)
3997                         return -EINVAL;
3998                 analyze_sbs(mddev);
3999         }
4000
4001         chunk_size = mddev->chunk_size;
4002
4003         if (chunk_size) {
4004                 if (chunk_size > MAX_CHUNK_SIZE) {
4005                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
4006                                 chunk_size, MAX_CHUNK_SIZE);
4007                         return -EINVAL;
4008                 }
4009                 /*
4010                  * chunk-size has to be a power of 2
4011                  */
4012                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
4013                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
4014                         return -EINVAL;
4015                 }
4016
4017                 /* devices must have minimum size of one chunk */
4018                 list_for_each_entry(rdev, &mddev->disks, same_set) {
4019                         if (test_bit(Faulty, &rdev->flags))
4020                                 continue;
4021                         if (rdev->sectors < chunk_size / 512) {
4022                                 printk(KERN_WARNING
4023                                         "md: Dev %s smaller than chunk_size:"
4024                                         " %llu < %d\n",
4025                                         bdevname(rdev->bdev,b),
4026                                         (unsigned long long)rdev->sectors,
4027                                         chunk_size / 512);
4028                                 return -EINVAL;
4029                         }
4030                 }
4031         }
4032
4033         if (mddev->level != LEVEL_NONE)
4034                 request_module("md-level-%d", mddev->level);
4035         else if (mddev->clevel[0])
4036                 request_module("md-%s", mddev->clevel);
4037
4038         /*
4039          * Drop all container device buffers, from now on
4040          * the only valid external interface is through the md
4041          * device.
4042          */
4043         list_for_each_entry(rdev, &mddev->disks, same_set) {
4044                 if (test_bit(Faulty, &rdev->flags))
4045                         continue;
4046                 sync_blockdev(rdev->bdev);
4047                 invalidate_bdev(rdev->bdev);
4048
4049                 /* perform some consistency tests on the device.
4050                  * We don't want the data to overlap the metadata,
4051                  * Internal Bitmap issues have been handled elsewhere.
4052                  */
4053                 if (rdev->data_offset < rdev->sb_start) {
4054                         if (mddev->dev_sectors &&
4055                             rdev->data_offset + mddev->dev_sectors
4056                             > rdev->sb_start) {
4057                                 printk("md: %s: data overlaps metadata\n",
4058                                        mdname(mddev));
4059                                 return -EINVAL;
4060                         }
4061                 } else {
4062                         if (rdev->sb_start + rdev->sb_size/512
4063                             > rdev->data_offset) {
4064                                 printk("md: %s: metadata overlaps data\n",
4065                                        mdname(mddev));
4066                                 return -EINVAL;
4067                         }
4068                 }
4069                 sysfs_notify_dirent(rdev->sysfs_state);
4070         }
4071
4072         md_probe(mddev->unit, NULL, NULL);
4073         disk = mddev->gendisk;
4074         if (!disk)
4075                 return -ENOMEM;
4076
4077         spin_lock(&pers_lock);
4078         pers = find_pers(mddev->level, mddev->clevel);
4079         if (!pers || !try_module_get(pers->owner)) {
4080                 spin_unlock(&pers_lock);
4081                 if (mddev->level != LEVEL_NONE)
4082                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
4083                                mddev->level);
4084                 else
4085                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
4086                                mddev->clevel);
4087                 return -EINVAL;
4088         }
4089         mddev->pers = pers;
4090         spin_unlock(&pers_lock);
4091         if (mddev->level != pers->level) {
4092                 mddev->level = pers->level;
4093                 mddev->new_level = pers->level;
4094         }
4095         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
4096
4097         if (pers->level >= 4 && pers->level <= 6)
4098                 /* Cannot support integrity (yet) */
4099                 blk_integrity_unregister(mddev->gendisk);
4100
4101         if (mddev->reshape_position != MaxSector &&
4102             pers->start_reshape == NULL) {
4103                 /* This personality cannot handle reshaping... */
4104                 mddev->pers = NULL;
4105                 module_put(pers->owner);
4106                 return -EINVAL;
4107         }
4108
4109         if (pers->sync_request) {
4110                 /* Warn if this is a potentially silly
4111                  * configuration.
4112                  */
4113                 char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4114                 mdk_rdev_t *rdev2;
4115                 int warned = 0;
4116
4117                 list_for_each_entry(rdev, &mddev->disks, same_set)
4118                         list_for_each_entry(rdev2, &mddev->disks, same_set) {
4119                                 if (rdev < rdev2 &&
4120                                     rdev->bdev->bd_contains ==
4121                                     rdev2->bdev->bd_contains) {
4122                                         printk(KERN_WARNING
4123                                                "%s: WARNING: %s appears to be"
4124                                                " on the same physical disk as"
4125                                                " %s.\n",
4126                                                mdname(mddev),
4127                                                bdevname(rdev->bdev,b),
4128                                                bdevname(rdev2->bdev,b2));
4129                                         warned = 1;
4130                                 }
4131                         }
4132
4133                 if (warned)
4134                         printk(KERN_WARNING
4135                                "True protection against single-disk"
4136                                " failure might be compromised.\n");
4137         }
4138
4139         mddev->recovery = 0;
4140         /* may be over-ridden by personality */
4141         mddev->resync_max_sectors = mddev->dev_sectors;
4142
4143         mddev->barriers_work = 1;
4144         mddev->ok_start_degraded = start_dirty_degraded;
4145
4146         if (start_readonly)
4147                 mddev->ro = 2; /* read-only, but switch on first write */
4148
4149         err = mddev->pers->run(mddev);
4150         if (err)
4151                 printk(KERN_ERR "md: pers->run() failed ...\n");
4152         else if (mddev->pers->size(mddev, 0, 0) < mddev->array_sectors) {
4153                 WARN_ONCE(!mddev->external_size, "%s: default size too small,"
4154                           " but 'external_size' not in effect?\n", __func__);
4155                 printk(KERN_ERR
4156                        "md: invalid array_size %llu > default size %llu\n",
4157                        (unsigned long long)mddev->array_sectors / 2,
4158                        (unsigned long long)mddev->pers->size(mddev, 0, 0) / 2);
4159                 err = -EINVAL;
4160                 mddev->pers->stop(mddev);
4161         }
4162         if (err == 0 && mddev->pers->sync_request) {
4163                 err = bitmap_create(mddev);
4164                 if (err) {
4165                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
4166                                mdname(mddev), err);
4167                         mddev->pers->stop(mddev);
4168                 }
4169         }
4170         if (err) {
4171                 module_put(mddev->pers->owner);
4172                 mddev->pers = NULL;
4173                 bitmap_destroy(mddev);
4174                 return err;
4175         }
4176         if (mddev->pers->sync_request) {
4177                 if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
4178                         printk(KERN_WARNING
4179                                "md: cannot register extra attributes for %s\n",
4180                                mdname(mddev));
4181                 mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action");
4182         } else if (mddev->ro == 2) /* auto-readonly not meaningful */
4183                 mddev->ro = 0;
4184
4185         atomic_set(&mddev->writes_pending,0);
4186         mddev->safemode = 0;
4187         mddev->safemode_timer.function = md_safemode_timeout;
4188         mddev->safemode_timer.data = (unsigned long) mddev;
4189         mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
4190         mddev->in_sync = 1;
4191
4192         list_for_each_entry(rdev, &mddev->disks, same_set)
4193                 if (rdev->raid_disk >= 0) {
4194                         char nm[20];
4195                         sprintf(nm, "rd%d", rdev->raid_disk);
4196                         if (sysfs_create_link(&mddev->kobj, &rdev->kobj, nm))
4197                                 printk("md: cannot register %s for %s\n",
4198                                        nm, mdname(mddev));
4199                 }
4200         
4201         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4202         
4203         if (mddev->flags)
4204                 md_update_sb(mddev, 0);
4205
4206         set_capacity(disk, mddev->array_sectors);
4207
4208         /* If there is a partially-recovered drive we need to
4209          * start recovery here.  If we leave it to md_check_recovery,
4210          * it will remove the drives and not do the right thing
4211          */
4212         if (mddev->degraded && !mddev->sync_thread) {
4213                 int spares = 0;
4214                 list_for_each_entry(rdev, &mddev->disks, same_set)
4215                         if (rdev->raid_disk >= 0 &&
4216                             !test_bit(In_sync, &rdev->flags) &&
4217                             !test_bit(Faulty, &rdev->flags))
4218                                 /* complete an interrupted recovery */
4219                                 spares++;
4220                 if (spares && mddev->pers->sync_request) {
4221                         mddev->recovery = 0;
4222                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
4223                         mddev->sync_thread = md_register_thread(md_do_sync,
4224                                                                 mddev,
4225                                                                 "%s_resync");
4226                         if (!mddev->sync_thread) {
4227                                 printk(KERN_ERR "%s: could not start resync"
4228                                        " thread...\n",
4229                                        mdname(mddev));
4230                                 /* leave the spares where they are, it shouldn't hurt */
4231                                 mddev->recovery = 0;
4232                         }
4233                 }
4234         }
4235         md_wakeup_thread(mddev->thread);
4236         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
4237
4238         mddev->changed = 1;
4239         md_new_event(mddev);
4240         sysfs_notify_dirent(mddev->sysfs_state);
4241         if (mddev->sysfs_action)
4242                 sysfs_notify_dirent(mddev->sysfs_action);
4243         sysfs_notify(&mddev->kobj, NULL, "degraded");
4244         kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
4245         return 0;
4246 }
4247
4248 static int restart_array(mddev_t *mddev)
4249 {
4250         struct gendisk *disk = mddev->gendisk;
4251
4252         /* Complain if it has no devices */
4253         if (list_empty(&mddev->disks))
4254                 return -ENXIO;
4255         if (!mddev->pers)
4256                 return -EINVAL;
4257         if (!mddev->ro)
4258                 return -EBUSY;
4259         mddev->safemode = 0;
4260         mddev->ro = 0;
4261         set_disk_ro(disk, 0);
4262         printk(KERN_INFO "md: %s switched to read-write mode.\n",
4263                 mdname(mddev));
4264         /* Kick recovery or resync if necessary */
4265         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4266         md_wakeup_thread(mddev->thread);
4267         md_wakeup_thread(mddev->sync_thread);
4268         sysfs_notify_dirent(mddev->sysfs_state);
4269         return 0;
4270 }
4271
4272 /* similar to deny_write_access, but accounts for our holding a reference
4273  * to the file ourselves */
4274 static int deny_bitmap_write_access(struct file * file)
4275 {
4276         struct inode *inode = file->f_mapping->host;
4277
4278         spin_lock(&inode->i_lock);
4279         if (atomic_read(&inode->i_writecount) > 1) {
4280                 spin_unlock(&inode->i_lock);
4281                 return -ETXTBSY;
4282         }
4283         atomic_set(&inode->i_writecount, -1);
4284         spin_unlock(&inode->i_lock);
4285
4286         return 0;
4287 }
4288
4289 static void restore_bitmap_write_access(struct file *file)
4290 {
4291         struct inode *inode = file->f_mapping->host;
4292
4293         spin_lock(&inode->i_lock);
4294         atomic_set(&inode->i_writecount, 1);
4295         spin_unlock(&inode->i_lock);
4296 }
4297
4298 /* mode:
4299  *   0 - completely stop and dis-assemble array
4300  *   1 - switch to readonly
4301  *   2 - stop but do not disassemble array
4302  */
4303 static int do_md_stop(mddev_t * mddev, int mode, int is_open)
4304 {
4305         int err = 0;
4306         struct gendisk *disk = mddev->gendisk;
4307         mdk_rdev_t *rdev;
4308
4309         if (atomic_read(&mddev->openers) > is_open) {
4310                 printk("md: %s still in use.\n",mdname(mddev));
4311                 return -EBUSY;
4312         }
4313
4314         if (mddev->pers) {
4315
4316                 if (mddev->sync_thread) {
4317                         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4318                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4319                         md_unregister_thread(mddev->sync_thread);
4320                         mddev->sync_thread = NULL;
4321                 }
4322
4323                 del_timer_sync(&mddev->safemode_timer);
4324
4325                 switch(mode) {
4326                 case 1: /* readonly */
4327                         err  = -ENXIO;
4328                         if (mddev->ro==1)
4329                                 goto out;
4330                         mddev->ro = 1;
4331                         break;
4332                 case 0: /* disassemble */
4333                 case 2: /* stop */
4334                         bitmap_flush(mddev);
4335                         md_super_wait(mddev);
4336                         if (mddev->ro)
4337                                 set_disk_ro(disk, 0);
4338
4339                         mddev->pers->stop(mddev);
4340                         mddev->queue->merge_bvec_fn = NULL;
4341                         mddev->queue->unplug_fn = NULL;
4342                         mddev->queue->backing_dev_info.congested_fn = NULL;
4343                         module_put(mddev->pers->owner);
4344                         if (mddev->pers->sync_request)
4345                                 mddev->private = &md_redundancy_group;
4346                         mddev->pers = NULL;
4347                         /* tell userspace to handle 'inactive' */
4348                         sysfs_notify_dirent(mddev->sysfs_state);
4349
4350                         list_for_each_entry(rdev, &mddev->disks, same_set)
4351                                 if (rdev->raid_disk >= 0) {
4352                                         char nm[20];
4353                                         sprintf(nm, "rd%d", rdev->raid_disk);
4354                                         sysfs_remove_link(&mddev->kobj, nm);
4355                                 }
4356
4357                         set_capacity(disk, 0);
4358                         mddev->changed = 1;
4359
4360                         if (mddev->ro)
4361                                 mddev->ro = 0;
4362                 }
4363                 if (!mddev->in_sync || mddev->flags) {
4364                         /* mark array as shutdown cleanly */
4365                         mddev->in_sync = 1;
4366                         md_update_sb(mddev, 1);
4367                 }
4368                 if (mode == 1)
4369                         set_disk_ro(disk, 1);
4370                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4371         }
4372
4373         /*
4374          * Free resources if final stop
4375          */
4376         if (mode == 0) {
4377
4378                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
4379
4380                 bitmap_destroy(mddev);
4381                 if (mddev->bitmap_file) {
4382                         restore_bitmap_write_access(mddev->bitmap_file);
4383                         fput(mddev->bitmap_file);
4384                         mddev->bitmap_file = NULL;
4385                 }
4386                 mddev->bitmap_offset = 0;
4387
4388                 /* make sure all md_delayed_delete calls have finished */
4389                 flush_scheduled_work();
4390
4391                 export_array(mddev);
4392
4393                 mddev->array_sectors = 0;
4394                 mddev->external_size = 0;
4395                 mddev->dev_sectors = 0;
4396                 mddev->raid_disks = 0;
4397                 mddev->recovery_cp = 0;
4398                 mddev->resync_min = 0;
4399                 mddev->resync_max = MaxSector;
4400                 mddev->reshape_position = MaxSector;
4401                 mddev->external = 0;
4402                 mddev->persistent = 0;
4403                 mddev->level = LEVEL_NONE;
4404                 mddev->clevel[0] = 0;
4405                 mddev->flags = 0;
4406                 mddev->ro = 0;
4407                 mddev->metadata_type[0] = 0;
4408                 mddev->chunk_size = 0;
4409                 mddev->ctime = mddev->utime = 0;
4410                 mddev->layout = 0;
4411                 mddev->max_disks = 0;
4412                 mddev->events = 0;
4413                 mddev->delta_disks = 0;
4414                 mddev->new_level = LEVEL_NONE;
4415                 mddev->new_layout = 0;
4416                 mddev->new_chunk = 0;
4417                 mddev->curr_resync = 0;
4418                 mddev->resync_mismatches = 0;
4419                 mddev->suspend_lo = mddev->suspend_hi = 0;
4420                 mddev->sync_speed_min = mddev->sync_speed_max = 0;
4421                 mddev->recovery = 0;
4422                 mddev->in_sync = 0;
4423                 mddev->changed = 0;
4424                 mddev->degraded = 0;
4425                 mddev->barriers_work = 0;
4426                 mddev->safemode = 0;
4427                 kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
4428                 if (mddev->hold_active == UNTIL_STOP)
4429                         mddev->hold_active = 0;
4430
4431         } else if (mddev->pers)
4432                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
4433                         mdname(mddev));
4434         err = 0;
4435         blk_integrity_unregister(disk);
4436         md_new_event(mddev);
4437         sysfs_notify_dirent(mddev->sysfs_state);
4438 out:
4439         return err;
4440 }
4441
4442 #ifndef MODULE
4443 static void autorun_array(mddev_t *mddev)
4444 {
4445         mdk_rdev_t *rdev;
4446         int err;
4447
4448         if (list_empty(&mddev->disks))
4449                 return;
4450
4451         printk(KERN_INFO "md: running: ");
4452
4453         list_for_each_entry(rdev, &mddev->disks, same_set) {
4454                 char b[BDEVNAME_SIZE];
4455                 printk("<%s>", bdevname(rdev->bdev,b));
4456         }
4457         printk("\n");
4458
4459         err = do_md_run(mddev);
4460         if (err) {
4461                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
4462                 do_md_stop(mddev, 0, 0);
4463         }
4464 }
4465
4466 /*
4467  * lets try to run arrays based on all disks that have arrived
4468  * until now. (those are in pending_raid_disks)
4469  *
4470  * the method: pick the first pending disk, collect all disks with
4471  * the same UUID, remove all from the pending list and put them into
4472  * the 'same_array' list. Then order this list based on superblock
4473  * update time (freshest comes first), kick out 'old' disks and
4474  * compare superblocks. If everything's fine then run it.
4475  *
4476  * If "unit" is allocated, then bump its reference count
4477  */
4478 static void autorun_devices(int part)
4479 {
4480         mdk_rdev_t *rdev0, *rdev, *tmp;
4481         mddev_t *mddev;
4482         char b[BDEVNAME_SIZE];
4483
4484         printk(KERN_INFO "md: autorun ...\n");
4485         while (!list_empty(&pending_raid_disks)) {
4486                 int unit;
4487                 dev_t dev;
4488                 LIST_HEAD(candidates);
4489                 rdev0 = list_entry(pending_raid_disks.next,
4490                                          mdk_rdev_t, same_set);
4491
4492                 printk(KERN_INFO "md: considering %s ...\n",
4493                         bdevname(rdev0->bdev,b));
4494                 INIT_LIST_HEAD(&candidates);
4495                 rdev_for_each_list(rdev, tmp, &pending_raid_disks)
4496                         if (super_90_load(rdev, rdev0, 0) >= 0) {
4497                                 printk(KERN_INFO "md:  adding %s ...\n",
4498                                         bdevname(rdev->bdev,b));
4499                                 list_move(&rdev->same_set, &candidates);
4500                         }
4501                 /*
4502                  * now we have a set of devices, with all of them having
4503                  * mostly sane superblocks. It's time to allocate the
4504                  * mddev.
4505                  */
4506                 if (part) {
4507                         dev = MKDEV(mdp_major,
4508                                     rdev0->preferred_minor << MdpMinorShift);
4509                         unit = MINOR(dev) >> MdpMinorShift;
4510                 } else {
4511                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
4512                         unit = MINOR(dev);
4513                 }
4514                 if (rdev0->preferred_minor != unit) {
4515                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
4516                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
4517                         break;
4518                 }
4519
4520                 md_probe(dev, NULL, NULL);
4521                 mddev = mddev_find(dev);
4522                 if (!mddev || !mddev->gendisk) {
4523                         if (mddev)
4524                                 mddev_put(mddev);
4525                         printk(KERN_ERR
4526                                 "md: cannot allocate memory for md drive.\n");
4527                         break;
4528                 }
4529                 if (mddev_lock(mddev)) 
4530                         printk(KERN_WARNING "md: %s locked, cannot run\n",
4531                                mdname(mddev));
4532                 else if (mddev->raid_disks || mddev->major_version
4533                          || !list_empty(&mddev->disks)) {
4534                         printk(KERN_WARNING 
4535                                 "md: %s already running, cannot run %s\n",
4536                                 mdname(mddev), bdevname(rdev0->bdev,b));
4537                         mddev_unlock(mddev);
4538                 } else {
4539                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
4540                         mddev->persistent = 1;
4541                         rdev_for_each_list(rdev, tmp, &candidates) {
4542                                 list_del_init(&rdev->same_set);
4543                                 if (bind_rdev_to_array(rdev, mddev))
4544                                         export_rdev(rdev);
4545                         }
4546                         autorun_array(mddev);
4547                         mddev_unlock(mddev);
4548                 }
4549                 /* on success, candidates will be empty, on error
4550                  * it won't...
4551                  */
4552                 rdev_for_each_list(rdev, tmp, &candidates) {
4553                         list_del_init(&rdev->same_set);
4554                         export_rdev(rdev);
4555                 }
4556                 mddev_put(mddev);
4557         }
4558         printk(KERN_INFO "md: ... autorun DONE.\n");
4559 }
4560 #endif /* !MODULE */
4561
4562 static int get_version(void __user * arg)
4563 {
4564         mdu_version_t ver;
4565
4566         ver.major = MD_MAJOR_VERSION;
4567         ver.minor = MD_MINOR_VERSION;
4568         ver.patchlevel = MD_PATCHLEVEL_VERSION;
4569
4570         if (copy_to_user(arg, &ver, sizeof(ver)))
4571                 return -EFAULT;
4572
4573         return 0;
4574 }
4575
4576 static int get_array_info(mddev_t * mddev, void __user * arg)
4577 {
4578         mdu_array_info_t info;
4579         int nr,working,active,failed,spare;
4580         mdk_rdev_t *rdev;
4581
4582         nr=working=active=failed=spare=0;
4583         list_for_each_entry(rdev, &mddev->disks, same_set) {
4584                 nr++;
4585                 if (test_bit(Faulty, &rdev->flags))
4586                         failed++;
4587                 else {
4588                         working++;
4589                         if (test_bit(In_sync, &rdev->flags))
4590                                 active++;       
4591                         else
4592                                 spare++;
4593                 }
4594         }
4595
4596         info.major_version = mddev->major_version;
4597         info.minor_version = mddev->minor_version;
4598         info.patch_version = MD_PATCHLEVEL_VERSION;
4599         info.ctime         = mddev->ctime;
4600         info.level         = mddev->level;
4601         info.size          = mddev->dev_sectors / 2;
4602         if (info.size != mddev->dev_sectors / 2) /* overflow */
4603                 info.size = -1;
4604         info.nr_disks      = nr;
4605         info.raid_disks    = mddev->raid_disks;
4606         info.md_minor      = mddev->md_minor;
4607         info.not_persistent= !mddev->persistent;
4608
4609         info.utime         = mddev->utime;
4610         info.state         = 0;
4611         if (mddev->in_sync)
4612                 info.state = (1<<MD_SB_CLEAN);
4613         if (mddev->bitmap && mddev->bitmap_offset)
4614                 info.state = (1<<MD_SB_BITMAP_PRESENT);
4615         info.active_disks  = active;
4616         info.working_disks = working;
4617         info.failed_disks  = failed;
4618         info.spare_disks   = spare;
4619
4620         info.layout        = mddev->layout;
4621         info.chunk_size    = mddev->chunk_size;
4622
4623         if (copy_to_user(arg, &info, sizeof(info)))
4624                 return -EFAULT;
4625
4626         return 0;
4627 }
4628
4629 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
4630 {
4631         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
4632         char *ptr, *buf = NULL;
4633         int err = -ENOMEM;
4634
4635         if (md_allow_write(mddev))
4636                 file = kmalloc(sizeof(*file), GFP_NOIO);
4637         else
4638                 file = kmalloc(sizeof(*file), GFP_KERNEL);
4639
4640         if (!file)
4641                 goto out;
4642
4643         /* bitmap disabled, zero the first byte and copy out */
4644         if (!mddev->bitmap || !mddev->bitmap->file) {
4645                 file->pathname[0] = '\0';
4646                 goto copy_out;
4647         }
4648
4649         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
4650         if (!buf)
4651                 goto out;
4652
4653         ptr = d_path(&mddev->bitmap->file->f_path, buf, sizeof(file->pathname));
4654         if (IS_ERR(ptr))
4655                 goto out;
4656
4657         strcpy(file->pathname, ptr);
4658
4659 copy_out:
4660         err = 0;
4661         if (copy_to_user(arg, file, sizeof(*file)))
4662                 err = -EFAULT;
4663 out:
4664         kfree(buf);
4665         kfree(file);
4666         return err;
4667 }
4668
4669 static int get_disk_info(mddev_t * mddev, void __user * arg)
4670 {
4671         mdu_disk_info_t info;
4672         mdk_rdev_t *rdev;
4673
4674         if (copy_from_user(&info, arg, sizeof(info)))
4675                 return -EFAULT;
4676
4677         rdev = find_rdev_nr(mddev, info.number);
4678         if (rdev) {
4679                 info.major = MAJOR(rdev->bdev->bd_dev);
4680                 info.minor = MINOR(rdev->bdev->bd_dev);
4681                 info.raid_disk = rdev->raid_disk;
4682                 info.state = 0;
4683                 if (test_bit(Faulty, &rdev->flags))
4684                         info.state |= (1<<MD_DISK_FAULTY);
4685                 else if (test_bit(In_sync, &rdev->flags)) {
4686                         info.state |= (1<<MD_DISK_ACTIVE);
4687                         info.state |= (1<<MD_DISK_SYNC);
4688                 }
4689                 if (test_bit(WriteMostly, &rdev->flags))
4690                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
4691         } else {
4692                 info.major = info.minor = 0;
4693                 info.raid_disk = -1;
4694                 info.state = (1<<MD_DISK_REMOVED);
4695         }
4696
4697         if (copy_to_user(arg, &info, sizeof(info)))
4698                 return -EFAULT;
4699
4700         return 0;
4701 }
4702
4703 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
4704 {
4705         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4706         mdk_rdev_t *rdev;
4707         dev_t dev = MKDEV(info->major,info->minor);
4708
4709         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
4710                 return -EOVERFLOW;
4711
4712         if (!mddev->raid_disks) {
4713                 int err;
4714                 /* expecting a device which has a superblock */
4715                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
4716                 if (IS_ERR(rdev)) {
4717                         printk(KERN_WARNING 
4718                                 "md: md_import_device returned %ld\n",
4719                                 PTR_ERR(rdev));
4720                         return PTR_ERR(rdev);
4721                 }
4722                 if (!list_empty(&mddev->disks)) {
4723                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
4724                                                         mdk_rdev_t, same_set);
4725                         int err = super_types[mddev->major_version]
4726                                 .load_super(rdev, rdev0, mddev->minor_version);
4727                         if (err < 0) {
4728                                 printk(KERN_WARNING 
4729                                         "md: %s has different UUID to %s\n",
4730                                         bdevname(rdev->bdev,b), 
4731                                         bdevname(rdev0->bdev,b2));
4732                                 export_rdev(rdev);
4733                                 return -EINVAL;
4734                         }
4735                 }
4736                 err = bind_rdev_to_array(rdev, mddev);
4737                 if (err)
4738                         export_rdev(rdev);
4739                 return err;
4740         }
4741
4742         /*
4743          * add_new_disk can be used once the array is assembled
4744          * to add "hot spares".  They must already have a superblock
4745          * written
4746          */
4747         if (mddev->pers) {
4748                 int err;
4749                 if (!mddev->pers->hot_add_disk) {
4750                         printk(KERN_WARNING 
4751                                 "%s: personality does not support diskops!\n",
4752                                mdname(mddev));
4753                         return -EINVAL;
4754                 }
4755                 if (mddev->persistent)
4756                         rdev = md_import_device(dev, mddev->major_version,
4757                                                 mddev->minor_version);
4758                 else
4759                         rdev = md_import_device(dev, -1, -1);
4760                 if (IS_ERR(rdev)) {
4761                         printk(KERN_WARNING 
4762                                 "md: md_import_device returned %ld\n",
4763                                 PTR_ERR(rdev));
4764                         return PTR_ERR(rdev);
4765                 }
4766                 /* set save_raid_disk if appropriate */
4767                 if (!mddev->persistent) {
4768                         if (info->state & (1<<MD_DISK_SYNC)  &&
4769                             info->raid_disk < mddev->raid_disks)
4770                                 rdev->raid_disk = info->raid_disk;
4771                         else
4772                                 rdev->raid_disk = -1;
4773                 } else
4774                         super_types[mddev->major_version].
4775                                 validate_super(mddev, rdev);
4776                 rdev->saved_raid_disk = rdev->raid_disk;
4777
4778                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
4779                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4780                         set_bit(WriteMostly, &rdev->flags);
4781                 else
4782                         clear_bit(WriteMostly, &rdev->flags);
4783
4784                 rdev->raid_disk = -1;
4785                 err = bind_rdev_to_array(rdev, mddev);
4786                 if (!err && !mddev->pers->hot_remove_disk) {
4787                         /* If there is hot_add_disk but no hot_remove_disk
4788                          * then added disks for geometry changes,
4789                          * and should be added immediately.
4790                          */
4791                         super_types[mddev->major_version].
4792                                 validate_super(mddev, rdev);
4793                         err = mddev->pers->hot_add_disk(mddev, rdev);
4794                         if (err)
4795                                 unbind_rdev_from_array(rdev);
4796                 }
4797                 if (err)
4798                         export_rdev(rdev);
4799                 else
4800                         sysfs_notify_dirent(rdev->sysfs_state);
4801
4802                 md_update_sb(mddev, 1);
4803                 if (mddev->degraded)
4804                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4805                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4806                 md_wakeup_thread(mddev->thread);
4807                 return err;
4808         }
4809
4810         /* otherwise, add_new_disk is only allowed
4811          * for major_version==0 superblocks
4812          */
4813         if (mddev->major_version != 0) {
4814                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
4815                        mdname(mddev));
4816                 return -EINVAL;
4817         }
4818
4819         if (!(info->state & (1<<MD_DISK_FAULTY))) {
4820                 int err;
4821                 rdev = md_import_device(dev, -1, 0);
4822                 if (IS_ERR(rdev)) {
4823                         printk(KERN_WARNING 
4824                                 "md: error, md_import_device() returned %ld\n",
4825                                 PTR_ERR(rdev));
4826                         return PTR_ERR(rdev);
4827                 }
4828                 rdev->desc_nr = info->number;
4829                 if (info->raid_disk < mddev->raid_disks)
4830                         rdev->raid_disk = info->raid_disk;
4831                 else
4832                         rdev->raid_disk = -1;
4833
4834                 if (rdev->raid_disk < mddev->raid_disks)
4835                         if (info->state & (1<<MD_DISK_SYNC))
4836                                 set_bit(In_sync, &rdev->flags);
4837
4838                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4839                         set_bit(WriteMostly, &rdev->flags);
4840
4841                 if (!mddev->persistent) {
4842                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
4843                         rdev->sb_start = rdev->bdev->bd_inode->i_size / 512;
4844                 } else 
4845                         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
4846                 rdev->sectors = calc_num_sectors(rdev, mddev->chunk_size);
4847
4848                 err = bind_rdev_to_array(rdev, mddev);
4849                 if (err) {
4850                         export_rdev(rdev);
4851                         return err;
4852                 }
4853         }
4854
4855         return 0;
4856 }
4857
4858 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
4859 {
4860         char b[BDEVNAME_SIZE];
4861         mdk_rdev_t *rdev;
4862
4863         rdev = find_rdev(mddev, dev);
4864         if (!rdev)
4865                 return -ENXIO;
4866
4867         if (rdev->raid_disk >= 0)
4868                 goto busy;
4869
4870         kick_rdev_from_array(rdev);
4871         md_update_sb(mddev, 1);
4872         md_new_event(mddev);
4873
4874         return 0;
4875 busy:
4876         printk(KERN_WARNING "md: cannot remove active disk %s from %s ...\n",
4877                 bdevname(rdev->bdev,b), mdname(mddev));
4878         return -EBUSY;
4879 }
4880
4881 static int hot_add_disk(mddev_t * mddev, dev_t dev)
4882 {
4883         char b[BDEVNAME_SIZE];
4884         int err;
4885         mdk_rdev_t *rdev;
4886
4887         if (!mddev->pers)
4888                 return -ENODEV;
4889
4890         if (mddev->major_version != 0) {
4891                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
4892                         " version-0 superblocks.\n",
4893                         mdname(mddev));
4894                 return -EINVAL;
4895         }
4896         if (!mddev->pers->hot_add_disk) {
4897                 printk(KERN_WARNING 
4898                         "%s: personality does not support diskops!\n",
4899                         mdname(mddev));
4900                 return -EINVAL;
4901         }
4902
4903         rdev = md_import_device(dev, -1, 0);
4904         if (IS_ERR(rdev)) {
4905                 printk(KERN_WARNING 
4906                         "md: error, md_import_device() returned %ld\n",
4907                         PTR_ERR(rdev));
4908                 return -EINVAL;
4909         }
4910
4911         if (mddev->persistent)
4912                 rdev->sb_start = calc_dev_sboffset(rdev->bdev);
4913         else
4914                 rdev->sb_start = rdev->bdev->bd_inode->i_size / 512;
4915
4916         rdev->sectors = calc_num_sectors(rdev, mddev->chunk_size);
4917
4918         if (test_bit(Faulty, &rdev->flags)) {
4919                 printk(KERN_WARNING 
4920                         "md: can not hot-add faulty %s disk to %s!\n",
4921                         bdevname(rdev->bdev,b), mdname(mddev));
4922                 err = -EINVAL;
4923                 goto abort_export;
4924         }
4925         clear_bit(In_sync, &rdev->flags);
4926         rdev->desc_nr = -1;
4927         rdev->saved_raid_disk = -1;
4928         err = bind_rdev_to_array(rdev, mddev);
4929         if (err)
4930                 goto abort_export;
4931
4932         /*
4933          * The rest should better be atomic, we can have disk failures
4934          * noticed in interrupt contexts ...
4935          */
4936
4937         rdev->raid_disk = -1;
4938
4939         md_update_sb(mddev, 1);
4940
4941         /*
4942          * Kick recovery, maybe this spare has to be added to the
4943          * array immediately.
4944          */
4945         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4946         md_wakeup_thread(mddev->thread);
4947         md_new_event(mddev);
4948         return 0;
4949
4950 abort_export:
4951         export_rdev(rdev);
4952         return err;
4953 }
4954
4955 static int set_bitmap_file(mddev_t *mddev, int fd)
4956 {
4957         int err;
4958
4959         if (mddev->pers) {
4960                 if (!mddev->pers->quiesce)
4961                         return -EBUSY;
4962                 if (mddev->recovery || mddev->sync_thread)
4963                         return -EBUSY;
4964                 /* we should be able to change the bitmap.. */
4965         }
4966
4967
4968         if (fd >= 0) {
4969                 if (mddev->bitmap)
4970                         return -EEXIST; /* cannot add when bitmap is present */
4971                 mddev->bitmap_file = fget(fd);
4972
4973                 if (mddev->bitmap_file == NULL) {
4974                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
4975                                mdname(mddev));
4976                         return -EBADF;
4977                 }
4978
4979                 err = deny_bitmap_write_access(mddev->bitmap_file);
4980                 if (err) {
4981                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
4982                                mdname(mddev));
4983                         fput(mddev->bitmap_file);
4984                         mddev->bitmap_file = NULL;
4985                         return err;
4986                 }
4987                 mddev->bitmap_offset = 0; /* file overrides offset */
4988         } else if (mddev->bitmap == NULL)
4989                 return -ENOENT; /* cannot remove what isn't there */
4990         err = 0;
4991         if (mddev->pers) {
4992                 mddev->pers->quiesce(mddev, 1);
4993                 if (fd >= 0)
4994                         err = bitmap_create(mddev);
4995                 if (fd < 0 || err) {
4996                         bitmap_destroy(mddev);
4997                         fd = -1; /* make sure to put the file */
4998                 }
4999                 mddev->pers->quiesce(mddev, 0);
5000         }
5001         if (fd < 0) {
5002                 if (mddev->bitmap_file) {
5003                         restore_bitmap_write_access(mddev->bitmap_file);
5004                         fput(mddev->bitmap_file);
5005                 }
5006                 mddev->bitmap_file = NULL;
5007         }
5008
5009         return err;
5010 }
5011
5012 /*
5013  * set_array_info is used two different ways
5014  * The original usage is when creating a new array.
5015  * In this usage, raid_disks is > 0 and it together with
5016  *  level, size, not_persistent,layout,chunksize determine the
5017  *  shape of the array.
5018  *  This will always create an array with a type-0.90.0 superblock.
5019  * The newer usage is when assembling an array.
5020  *  In this case raid_disks will be 0, and the major_version field is
5021  *  use to determine which style super-blocks are to be found on the devices.
5022  *  The minor and patch _version numbers are also kept incase the
5023  *  super_block handler wishes to interpret them.
5024  */
5025 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
5026 {
5027
5028         if (info->raid_disks == 0) {
5029                 /* just setting version number for superblock loading */
5030                 if (info->major_version < 0 ||
5031                     info->major_version >= ARRAY_SIZE(super_types) ||
5032                     super_types[info->major_version].name == NULL) {
5033                         /* maybe try to auto-load a module? */
5034                         printk(KERN_INFO 
5035                                 "md: superblock version %d not known\n",
5036                                 info->major_version);
5037                         return -EINVAL;
5038                 }
5039                 mddev->major_version = info->major_version;
5040                 mddev->minor_version = info->minor_version;
5041                 mddev->patch_version = info->patch_version;
5042                 mddev->persistent = !info->not_persistent;
5043                 return 0;
5044         }
5045         mddev->major_version = MD_MAJOR_VERSION;
5046         mddev->minor_version = MD_MINOR_VERSION;
5047         mddev->patch_version = MD_PATCHLEVEL_VERSION;
5048         mddev->ctime         = get_seconds();
5049
5050         mddev->level         = info->level;
5051         mddev->clevel[0]     = 0;
5052         mddev->dev_sectors   = 2 * (sector_t)info->size;
5053         mddev->raid_disks    = info->raid_disks;
5054         /* don't set md_minor, it is determined by which /dev/md* was
5055          * openned
5056          */
5057         if (info->state & (1<<MD_SB_CLEAN))
5058                 mddev->recovery_cp = MaxSector;
5059         else
5060                 mddev->recovery_cp = 0;
5061         mddev->persistent    = ! info->not_persistent;
5062         mddev->external      = 0;
5063
5064         mddev->layout        = info->layout;
5065         mddev->chunk_size    = info->chunk_size;
5066
5067         mddev->max_disks     = MD_SB_DISKS;
5068
5069         if (mddev->persistent)
5070                 mddev->flags         = 0;
5071         set_bit(MD_CHANGE_DEVS, &mddev->flags);
5072
5073         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
5074         mddev->bitmap_offset = 0;
5075
5076         mddev->reshape_position = MaxSector;
5077
5078         /*
5079          * Generate a 128 bit UUID
5080          */
5081         get_random_bytes(mddev->uuid, 16);
5082
5083         mddev->new_level = mddev->level;
5084         mddev->new_chunk = mddev->chunk_size;
5085         mddev->new_layout = mddev->layout;
5086         mddev->delta_disks = 0;
5087
5088         return 0;
5089 }
5090
5091 void md_set_array_sectors(mddev_t *mddev, sector_t array_sectors)
5092 {
5093         WARN(!mddev_is_locked(mddev), "%s: unlocked mddev!\n", __func__);
5094
5095         if (mddev->external_size)
5096                 return;
5097
5098         mddev->array_sectors = array_sectors;
5099 }
5100 EXPORT_SYMBOL(md_set_array_sectors);
5101
5102 static int update_size(mddev_t *mddev, sector_t num_sectors)
5103 {
5104         mdk_rdev_t *rdev;
5105         int rv;
5106         int fit = (num_sectors == 0);
5107
5108         if (mddev->pers->resize == NULL)
5109                 return -EINVAL;
5110         /* The "num_sectors" is the number of sectors of each device that
5111          * is used.  This can only make sense for arrays with redundancy.
5112          * linear and raid0 always use whatever space is available. We can only
5113          * consider changing this number if no resync or reconstruction is
5114          * happening, and if the new size is acceptable. It must fit before the
5115          * sb_start or, if that is <data_offset, it must fit before the size
5116          * of each device.  If num_sectors is zero, we find the largest size
5117          * that fits.
5118
5119          */
5120         if (mddev->sync_thread)
5121                 return -EBUSY;
5122         if (mddev->bitmap)
5123                 /* Sorry, cannot grow a bitmap yet, just remove it,
5124                  * grow, and re-add.
5125                  */
5126                 return -EBUSY;
5127         list_for_each_entry(rdev, &mddev->disks, same_set) {
5128                 sector_t avail = rdev->sectors;
5129
5130                 if (fit && (num_sectors == 0 || num_sectors > avail))
5131                         num_sectors = avail;
5132                 if (avail < num_sectors)
5133                         return -ENOSPC;
5134         }
5135         rv = mddev->pers->resize(mddev, num_sectors);
5136         if (!rv) {
5137                 struct block_device *bdev;
5138
5139                 bdev = bdget_disk(mddev->gendisk, 0);
5140                 if (bdev) {
5141                         mutex_lock(&bdev->bd_inode->i_mutex);
5142                         i_size_write(bdev->bd_inode,
5143                                      (loff_t)mddev->array_sectors << 9);
5144                         mutex_unlock(&bdev->bd_inode->i_mutex);
5145                         bdput(bdev);
5146                 }
5147         }
5148         return rv;
5149 }
5150
5151 static int update_raid_disks(mddev_t *mddev, int raid_disks)
5152 {
5153         int rv;
5154         /* change the number of raid disks */
5155         if (mddev->pers->check_reshape == NULL)
5156                 return -EINVAL;
5157         if (raid_disks <= 0 ||
5158             raid_disks >= mddev->max_disks)
5159                 return -EINVAL;
5160         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
5161                 return -EBUSY;
5162         mddev->delta_disks = raid_disks - mddev->raid_disks;
5163
5164         rv = mddev->pers->check_reshape(mddev);
5165         return rv;
5166 }
5167
5168
5169 /*
5170  * update_array_info is used to change the configuration of an
5171  * on-line array.
5172  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
5173  * fields in the info are checked against the array.
5174  * Any differences that cannot be handled will cause an error.
5175  * Normally, only one change can be managed at a time.
5176  */
5177 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
5178 {
5179         int rv = 0;
5180         int cnt = 0;
5181         int state = 0;
5182
5183         /* calculate expected state,ignoring low bits */
5184         if (mddev->bitmap && mddev->bitmap_offset)
5185                 state |= (1 << MD_SB_BITMAP_PRESENT);
5186
5187         if (mddev->major_version != info->major_version ||
5188             mddev->minor_version != info->minor_version ||
5189 /*          mddev->patch_version != info->patch_version || */
5190             mddev->ctime         != info->ctime         ||
5191             mddev->level         != info->level         ||
5192 /*          mddev->layout        != info->layout        || */
5193             !mddev->persistent   != info->not_persistent||
5194             mddev->chunk_size    != info->chunk_size    ||
5195             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
5196             ((state^info->state) & 0xfffffe00)
5197                 )
5198                 return -EINVAL;
5199         /* Check there is only one change */
5200         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
5201                 cnt++;
5202         if (mddev->raid_disks != info->raid_disks)
5203                 cnt++;
5204         if (mddev->layout != info->layout)
5205                 cnt++;
5206         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT))
5207                 cnt++;
5208         if (cnt == 0)
5209                 return 0;
5210         if (cnt > 1)
5211                 return -EINVAL;
5212
5213         if (mddev->layout != info->layout) {
5214                 /* Change layout
5215                  * we don't need to do anything at the md level, the
5216                  * personality will take care of it all.
5217                  */
5218                 if (mddev->pers->reconfig == NULL)
5219                         return -EINVAL;
5220                 else
5221                         return mddev->pers->reconfig(mddev, info->layout, -1);
5222         }
5223         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
5224                 rv = update_size(mddev, (sector_t)info->size * 2);
5225
5226         if (mddev->raid_disks    != info->raid_disks)
5227                 rv = update_raid_disks(mddev, info->raid_disks);
5228
5229         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
5230                 if (mddev->pers->quiesce == NULL)
5231                         return -EINVAL;
5232                 if (mddev->recovery || mddev->sync_thread)
5233                         return -EBUSY;
5234                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
5235                         /* add the bitmap */
5236                         if (mddev->bitmap)
5237                                 return -EEXIST;
5238                         if (mddev->default_bitmap_offset == 0)
5239                                 return -EINVAL;
5240                         mddev->bitmap_offset = mddev->default_bitmap_offset;
5241                         mddev->pers->quiesce(mddev, 1);
5242                         rv = bitmap_create(mddev);
5243                         if (rv)
5244                                 bitmap_destroy(mddev);
5245                         mddev->pers->quiesce(mddev, 0);
5246                 } else {
5247                         /* remove the bitmap */
5248                         if (!mddev->bitmap)
5249                                 return -ENOENT;
5250                         if (mddev->bitmap->file)
5251                                 return -EINVAL;
5252                         mddev->pers->quiesce(mddev, 1);
5253                         bitmap_destroy(mddev);
5254                         mddev->pers->quiesce(mddev, 0);
5255                         mddev->bitmap_offset = 0;
5256                 }
5257         }
5258         md_update_sb(mddev, 1);
5259         return rv;
5260 }
5261
5262 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
5263 {
5264         mdk_rdev_t *rdev;
5265
5266         if (mddev->pers == NULL)
5267                 return -ENODEV;
5268
5269         rdev = find_rdev(mddev, dev);
5270         if (!rdev)
5271                 return -ENODEV;
5272
5273         md_error(mddev, rdev);
5274         return 0;
5275 }
5276
5277 /*
5278  * We have a problem here : there is no easy way to give a CHS
5279  * virtual geometry. We currently pretend that we have a 2 heads
5280  * 4 sectors (with a BIG number of cylinders...). This drives
5281  * dosfs just mad... ;-)
5282  */
5283 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
5284 {
5285         mddev_t *mddev = bdev->bd_disk->private_data;
5286
5287         geo->heads = 2;
5288         geo->sectors = 4;
5289         geo->cylinders = get_capacity(mddev->gendisk) / 8;
5290         return 0;
5291 }
5292
5293 static int md_ioctl(struct block_device *bdev, fmode_t mode,
5294                         unsigned int cmd, unsigned long arg)
5295 {
5296         int err = 0;
5297         void __user *argp = (void __user *)arg;
5298         mddev_t *mddev = NULL;
5299
5300         if (!capable(CAP_SYS_ADMIN))
5301                 return -EACCES;
5302
5303         /*
5304          * Commands dealing with the RAID driver but not any
5305          * particular array:
5306          */
5307         switch (cmd)
5308         {
5309                 case RAID_VERSION:
5310                         err = get_version(argp);
5311                         goto done;
5312
5313                 case PRINT_RAID_DEBUG:
5314                         err = 0;
5315                         md_print_devices();
5316                         goto done;
5317
5318 #ifndef MODULE
5319                 case RAID_AUTORUN:
5320                         err = 0;
5321                         autostart_arrays(arg);
5322                         goto done;
5323 #endif
5324                 default:;
5325         }
5326
5327         /*
5328          * Commands creating/starting a new array:
5329          */
5330
5331         mddev = bdev->bd_disk->private_data;
5332
5333         if (!mddev) {
5334                 BUG();
5335                 goto abort;
5336         }
5337
5338         err = mddev_lock(mddev);
5339         if (err) {
5340                 printk(KERN_INFO 
5341                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
5342                         err, cmd);
5343                 goto abort;
5344         }
5345
5346         switch (cmd)
5347         {
5348                 case SET_ARRAY_INFO:
5349                         {
5350                                 mdu_array_info_t info;
5351                                 if (!arg)
5352                                         memset(&info, 0, sizeof(info));
5353                                 else if (copy_from_user(&info, argp, sizeof(info))) {
5354                                         err = -EFAULT;
5355                                         goto abort_unlock;
5356                                 }
5357                                 if (mddev->pers) {
5358                                         err = update_array_info(mddev, &info);
5359                                         if (err) {
5360                                                 printk(KERN_WARNING "md: couldn't update"
5361                                                        " array info. %d\n", err);
5362                                                 goto abort_unlock;
5363                                         }
5364                                         goto done_unlock;
5365                                 }
5366                                 if (!list_empty(&mddev->disks)) {
5367                                         printk(KERN_WARNING
5368                                                "md: array %s already has disks!\n",
5369                                                mdname(mddev));
5370                                         err = -EBUSY;
5371                                         goto abort_unlock;
5372                                 }
5373                                 if (mddev->raid_disks) {
5374                                         printk(KERN_WARNING
5375                                                "md: array %s already initialised!\n",
5376                                                mdname(mddev));
5377                                         err = -EBUSY;
5378                                         goto abort_unlock;
5379                                 }
5380                                 err = set_array_info(mddev, &info);
5381                                 if (err) {
5382                                         printk(KERN_WARNING "md: couldn't set"
5383                                                " array info. %d\n", err);
5384                                         goto abort_unlock;
5385                                 }
5386                         }
5387                         goto done_unlock;
5388
5389                 default:;
5390         }
5391
5392         /*
5393          * Commands querying/configuring an existing array:
5394          */
5395         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
5396          * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
5397         if ((!mddev->raid_disks && !mddev->external)
5398             && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
5399             && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
5400             && cmd != GET_BITMAP_FILE) {
5401                 err = -ENODEV;
5402                 goto abort_unlock;
5403         }
5404
5405         /*
5406          * Commands even a read-only array can execute:
5407          */
5408         switch (cmd)
5409         {
5410                 case GET_ARRAY_INFO:
5411                         err = get_array_info(mddev, argp);
5412                         goto done_unlock;
5413
5414                 case GET_BITMAP_FILE:
5415                         err = get_bitmap_file(mddev, argp);
5416                         goto done_unlock;
5417
5418                 case GET_DISK_INFO:
5419                         err = get_disk_info(mddev, argp);
5420                         goto done_unlock;
5421
5422                 case RESTART_ARRAY_RW:
5423                         err = restart_array(mddev);
5424                         goto done_unlock;
5425
5426                 case STOP_ARRAY:
5427                         err = do_md_stop(mddev, 0, 1);
5428                         goto done_unlock;
5429
5430                 case STOP_ARRAY_RO:
5431                         err = do_md_stop(mddev, 1, 1);
5432                         goto done_unlock;
5433
5434         }
5435
5436         /*
5437          * The remaining ioctls are changing the state of the
5438          * superblock, so we do not allow them on read-only arrays.
5439          * However non-MD ioctls (e.g. get-size) will still come through
5440          * here and hit the 'default' below, so only disallow
5441          * 'md' ioctls, and switch to rw mode if started auto-readonly.
5442          */
5443         if (_IOC_TYPE(cmd) == MD_MAJOR && mddev->ro && mddev->pers) {
5444                 if (mddev->ro == 2) {
5445                         mddev->ro = 0;
5446                         sysfs_notify_dirent(mddev->sysfs_state);
5447                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5448                         md_wakeup_thread(mddev->thread);
5449                 } else {
5450                         err = -EROFS;
5451                         goto abort_unlock;
5452                 }
5453         }
5454
5455         switch (cmd)
5456         {
5457                 case ADD_NEW_DISK:
5458                 {
5459                         mdu_disk_info_t info;
5460                         if (copy_from_user(&info, argp, sizeof(info)))
5461                                 err = -EFAULT;
5462                         else
5463                                 err = add_new_disk(mddev, &info);
5464                         goto done_unlock;
5465                 }
5466
5467                 case HOT_REMOVE_DISK:
5468                         err = hot_remove_disk(mddev, new_decode_dev(arg));
5469                         goto done_unlock;
5470
5471                 case HOT_ADD_DISK:
5472                         err = hot_add_disk(mddev, new_decode_dev(arg));
5473                         goto done_unlock;
5474
5475                 case SET_DISK_FAULTY:
5476                         err = set_disk_faulty(mddev, new_decode_dev(arg));
5477                         goto done_unlock;
5478
5479                 case RUN_ARRAY:
5480                         err = do_md_run(mddev);
5481                         goto done_unlock;
5482
5483                 case SET_BITMAP_FILE:
5484                         err = set_bitmap_file(mddev, (int)arg);
5485                         goto done_unlock;
5486
5487                 default:
5488                         err = -EINVAL;
5489                         goto abort_unlock;
5490         }
5491
5492 done_unlock:
5493 abort_unlock:
5494         if (mddev->hold_active == UNTIL_IOCTL &&
5495             err != -EINVAL)
5496                 mddev->hold_active = 0;
5497         mddev_unlock(mddev);
5498
5499         return err;
5500 done:
5501         if (err)
5502                 MD_BUG();
5503 abort:
5504         return err;
5505 }
5506
5507 static int md_open(struct block_device *bdev, fmode_t mode)
5508 {
5509         /*
5510          * Succeed if we can lock the mddev, which confirms that
5511          * it isn't being stopped right now.
5512          */
5513         mddev_t *mddev = mddev_find(bdev->bd_dev);
5514         int err;
5515
5516         if (mddev->gendisk != bdev->bd_disk) {
5517                 /* we are racing with mddev_put which is discarding this
5518                  * bd_disk.
5519                  */
5520                 mddev_put(mddev);
5521                 /* Wait until bdev->bd_disk is definitely gone */
5522                 flush_scheduled_work();
5523                 /* Then retry the open from the top */
5524                 return -ERESTARTSYS;
5525         }
5526         BUG_ON(mddev != bdev->bd_disk->private_data);
5527
5528         if ((err = mutex_lock_interruptible_nested(&mddev->reconfig_mutex, 1)))
5529                 goto out;
5530
5531         err = 0;
5532         atomic_inc(&mddev->openers);
5533         mddev_unlock(mddev);
5534
5535         check_disk_change(bdev);
5536  out:
5537         return err;
5538 }
5539
5540 static int md_release(struct gendisk *disk, fmode_t mode)
5541 {
5542         mddev_t *mddev = disk->private_data;
5543
5544         BUG_ON(!mddev);
5545         atomic_dec(&mddev->openers);
5546         mddev_put(mddev);
5547
5548         return 0;
5549 }
5550
5551 static int md_media_changed(struct gendisk *disk)
5552 {
5553         mddev_t *mddev = disk->private_data;
5554
5555         return mddev->changed;
5556 }
5557
5558 static int md_revalidate(struct gendisk *disk)
5559 {
5560         mddev_t *mddev = disk->private_data;
5561
5562         mddev->changed = 0;
5563         return 0;
5564 }
5565 static struct block_device_operations md_fops =
5566 {
5567         .owner          = THIS_MODULE,
5568         .open           = md_open,
5569         .release        = md_release,
5570         .locked_ioctl   = md_ioctl,
5571         .getgeo         = md_getgeo,
5572         .media_changed  = md_media_changed,
5573         .revalidate_disk= md_revalidate,
5574 };
5575
5576 static int md_thread(void * arg)
5577 {
5578         mdk_thread_t *thread = arg;
5579
5580         /*
5581          * md_thread is a 'system-thread', it's priority should be very
5582          * high. We avoid resource deadlocks individually in each
5583          * raid personality. (RAID5 does preallocation) We also use RR and
5584          * the very same RT priority as kswapd, thus we will never get
5585          * into a priority inversion deadlock.
5586          *
5587          * we definitely have to have equal or higher priority than
5588          * bdflush, otherwise bdflush will deadlock if there are too
5589          * many dirty RAID5 blocks.
5590          */
5591
5592         allow_signal(SIGKILL);
5593         while (!kthread_should_stop()) {
5594
5595                 /* We need to wait INTERRUPTIBLE so that
5596                  * we don't add to the load-average.
5597                  * That means we need to be sure no signals are
5598                  * pending
5599                  */
5600                 if (signal_pending(current))
5601                         flush_signals(current);
5602
5603                 wait_event_interruptible_timeout
5604                         (thread->wqueue,
5605                          test_bit(THREAD_WAKEUP, &thread->flags)
5606                          || kthread_should_stop(),
5607                          thread->timeout);
5608
5609                 clear_bit(THREAD_WAKEUP, &thread->flags);
5610
5611                 thread->run(thread->mddev);
5612         }
5613
5614         return 0;
5615 }
5616
5617 void md_wakeup_thread(mdk_thread_t *thread)
5618 {
5619         if (thread) {
5620                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
5621                 set_bit(THREAD_WAKEUP, &thread->flags);
5622                 wake_up(&thread->wqueue);
5623         }
5624 }
5625
5626 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
5627                                  const char *name)
5628 {
5629         mdk_thread_t *thread;
5630
5631         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
5632         if (!thread)
5633                 return NULL;
5634
5635         init_waitqueue_head(&thread->wqueue);
5636
5637         thread->run = run;
5638         thread->mddev = mddev;
5639         thread->timeout = MAX_SCHEDULE_TIMEOUT;
5640         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
5641         if (IS_ERR(thread->tsk)) {
5642                 kfree(thread);
5643                 return NULL;
5644         }
5645         return thread;
5646 }
5647
5648 void md_unregister_thread(mdk_thread_t *thread)
5649 {
5650         if (!thread)
5651                 return;
5652         dprintk("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
5653
5654         kthread_stop(thread->tsk);
5655         kfree(thread);
5656 }
5657
5658 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
5659 {
5660         if (!mddev) {
5661                 MD_BUG();
5662                 return;
5663         }
5664
5665         if (!rdev || test_bit(Faulty, &rdev->flags))
5666                 return;
5667
5668         if (mddev->external)
5669                 set_bit(Blocked, &rdev->flags);
5670 /*
5671         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
5672                 mdname(mddev),
5673                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
5674                 __builtin_return_address(0),__builtin_return_address(1),
5675                 __builtin_return_address(2),__builtin_return_address(3));
5676 */
5677         if (!mddev->pers)
5678                 return;
5679         if (!mddev->pers->error_handler)
5680                 return;
5681         mddev->pers->error_handler(mddev,rdev);
5682         if (mddev->degraded)
5683                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
5684         set_bit(StateChanged, &rdev->flags);
5685         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5686         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5687         md_wakeup_thread(mddev->thread);
5688         md_new_event_inintr(mddev);
5689 }
5690
5691 /* seq_file implementation /proc/mdstat */
5692
5693 static void status_unused(struct seq_file *seq)
5694 {
5695         int i = 0;
5696         mdk_rdev_t *rdev;
5697
5698         seq_printf(seq, "unused devices: ");
5699
5700         list_for_each_entry(rdev, &pending_raid_disks, same_set) {
5701                 char b[BDEVNAME_SIZE];
5702                 i++;
5703                 seq_printf(seq, "%s ",
5704                               bdevname(rdev->bdev,b));
5705         }
5706         if (!i)
5707                 seq_printf(seq, "<none>");
5708
5709         seq_printf(seq, "\n");
5710 }
5711
5712
5713 static void status_resync(struct seq_file *seq, mddev_t * mddev)
5714 {
5715         sector_t max_sectors, resync, res;
5716         unsigned long dt, db;
5717         sector_t rt;
5718         int scale;
5719         unsigned int per_milli;
5720
5721         resync = mddev->curr_resync - atomic_read(&mddev->recovery_active);
5722
5723         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
5724                 max_sectors = mddev->resync_max_sectors;
5725         else
5726                 max_sectors = mddev->dev_sectors;
5727
5728         /*
5729          * Should not happen.
5730          */
5731         if (!max_sectors) {
5732                 MD_BUG();
5733                 return;
5734         }
5735         /* Pick 'scale' such that (resync>>scale)*1000 will fit
5736          * in a sector_t, and (max_sectors>>scale) will fit in a
5737          * u32, as those are the requirements for sector_div.
5738          * Thus 'scale' must be at least 10
5739          */
5740         scale = 10;
5741         if (sizeof(sector_t) > sizeof(unsigned long)) {
5742                 while ( max_sectors/2 > (1ULL<<(scale+32)))
5743                         scale++;
5744         }
5745         res = (resync>>scale)*1000;
5746         sector_div(res, (u32)((max_sectors>>scale)+1));
5747
5748         per_milli = res;
5749         {
5750                 int i, x = per_milli/50, y = 20-x;
5751                 seq_printf(seq, "[");
5752                 for (i = 0; i < x; i++)
5753                         seq_printf(seq, "=");
5754                 seq_printf(seq, ">");
5755                 for (i = 0; i < y; i++)
5756                         seq_printf(seq, ".");
5757                 seq_printf(seq, "] ");
5758         }
5759         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
5760                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
5761                     "reshape" :
5762                     (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
5763                      "check" :
5764                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
5765                       "resync" : "recovery"))),
5766                    per_milli/10, per_milli % 10,
5767                    (unsigned long long) resync/2,
5768                    (unsigned long long) max_sectors/2);
5769
5770         /*
5771          * dt: time from mark until now
5772          * db: blocks written from mark until now
5773          * rt: remaining time
5774          *
5775          * rt is a sector_t, so could be 32bit or 64bit.
5776          * So we divide before multiply in case it is 32bit and close
5777          * to the limit.
5778          * We scale the divisor (db) by 32 to avoid loosing precision
5779          * near the end of resync when the number of remaining sectors
5780          * is close to 'db'.
5781          * We then divide rt by 32 after multiplying by db to compensate.
5782          * The '+1' avoids division by zero if db is very small.
5783          */
5784         dt = ((jiffies - mddev->resync_mark) / HZ);
5785         if (!dt) dt++;
5786         db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
5787                 - mddev->resync_mark_cnt;
5788
5789         rt = max_sectors - resync;    /* number of remaining sectors */
5790         sector_div(rt, db/32+1);
5791         rt *= dt;
5792         rt >>= 5;
5793
5794         seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60,
5795                    ((unsigned long)rt % 60)/6);
5796
5797         seq_printf(seq, " speed=%ldK/sec", db/2/dt);
5798 }
5799
5800 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
5801 {
5802         struct list_head *tmp;
5803         loff_t l = *pos;
5804         mddev_t *mddev;
5805
5806         if (l >= 0x10000)
5807                 return NULL;
5808         if (!l--)
5809                 /* header */
5810                 return (void*)1;
5811
5812         spin_lock(&all_mddevs_lock);
5813         list_for_each(tmp,&all_mddevs)
5814                 if (!l--) {
5815                         mddev = list_entry(tmp, mddev_t, all_mddevs);
5816                         mddev_get(mddev);
5817                         spin_unlock(&all_mddevs_lock);
5818                         return mddev;
5819                 }
5820         spin_unlock(&all_mddevs_lock);
5821         if (!l--)
5822                 return (void*)2;/* tail */
5823         return NULL;
5824 }
5825
5826 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
5827 {
5828         struct list_head *tmp;
5829         mddev_t *next_mddev, *mddev = v;
5830         
5831         ++*pos;
5832         if (v == (void*)2)
5833                 return NULL;
5834
5835         spin_lock(&all_mddevs_lock);
5836         if (v == (void*)1)
5837                 tmp = all_mddevs.next;
5838         else
5839                 tmp = mddev->all_mddevs.next;
5840         if (tmp != &all_mddevs)
5841                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
5842         else {
5843                 next_mddev = (void*)2;
5844                 *pos = 0x10000;
5845         }               
5846         spin_unlock(&all_mddevs_lock);
5847
5848         if (v != (void*)1)
5849                 mddev_put(mddev);
5850         return next_mddev;
5851
5852 }
5853
5854 static void md_seq_stop(struct seq_file *seq, void *v)
5855 {
5856         mddev_t *mddev = v;
5857
5858         if (mddev && v != (void*)1 && v != (void*)2)
5859                 mddev_put(mddev);
5860 }
5861
5862 struct mdstat_info {
5863         int event;
5864 };
5865
5866 static int md_seq_show(struct seq_file *seq, void *v)
5867 {
5868         mddev_t *mddev = v;
5869         sector_t sectors;
5870         mdk_rdev_t *rdev;
5871         struct mdstat_info *mi = seq->private;
5872         struct bitmap *bitmap;
5873
5874         if (v == (void*)1) {
5875                 struct mdk_personality *pers;
5876                 seq_printf(seq, "Personalities : ");
5877                 spin_lock(&pers_lock);
5878                 list_for_each_entry(pers, &pers_list, list)
5879                         seq_printf(seq, "[%s] ", pers->name);
5880
5881                 spin_unlock(&pers_lock);
5882                 seq_printf(seq, "\n");
5883                 mi->event = atomic_read(&md_event_count);
5884                 return 0;
5885         }
5886         if (v == (void*)2) {
5887                 status_unused(seq);
5888                 return 0;
5889         }
5890
5891         if (mddev_lock(mddev) < 0)
5892                 return -EINTR;
5893
5894         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
5895                 seq_printf(seq, "%s : %sactive", mdname(mddev),
5896                                                 mddev->pers ? "" : "in");
5897                 if (mddev->pers) {
5898                         if (mddev->ro==1)
5899                                 seq_printf(seq, " (read-only)");
5900                         if (mddev->ro==2)
5901                                 seq_printf(seq, " (auto-read-only)");
5902                         seq_printf(seq, " %s", mddev->pers->name);
5903                 }
5904