fccc8343a2501dbb8db452ea9e5469df11ef53e1
[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
1379         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1380                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1381                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1382         }
1383
1384         if (rdev->raid_disk >= 0 &&
1385             !test_bit(In_sync, &rdev->flags)) {
1386                 if (mddev->curr_resync_completed > rdev->recovery_offset)
1387                         rdev->recovery_offset = mddev->curr_resync_completed;
1388                 if (rdev->recovery_offset > 0) {
1389                         sb->feature_map |=
1390                                 cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1391                         sb->recovery_offset =
1392                                 cpu_to_le64(rdev->recovery_offset);
1393                 }
1394         }
1395
1396         if (mddev->reshape_position != MaxSector) {
1397                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1398                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1399                 sb->new_layout = cpu_to_le32(mddev->new_layout);
1400                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1401                 sb->new_level = cpu_to_le32(mddev->new_level);
1402                 sb->new_chunk = cpu_to_le32(mddev->new_chunk>>9);
1403         }
1404
1405         max_dev = 0;
1406         list_for_each_entry(rdev2, &mddev->disks, same_set)
1407                 if (rdev2->desc_nr+1 > max_dev)
1408                         max_dev = rdev2->desc_nr+1;
1409
1410         if (max_dev > le32_to_cpu(sb->max_dev))
1411                 sb->max_dev = cpu_to_le32(max_dev);
1412         for (i=0; i<max_dev;i++)
1413                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1414         
1415         list_for_each_entry(rdev2, &mddev->disks, same_set) {
1416                 i = rdev2->desc_nr;
1417                 if (test_bit(Faulty, &rdev2->flags))
1418                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1419                 else if (test_bit(In_sync, &rdev2->flags))
1420                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1421                 else if (rdev2->raid_disk >= 0 && rdev2->recovery_offset > 0)
1422                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1423                 else
1424                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1425         }
1426
1427         sb->sb_csum = calc_sb_1_csum(sb);
1428 }
1429
1430 static unsigned long long
1431 super_1_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
1432 {
1433         struct mdp_superblock_1 *sb;
1434         sector_t max_sectors;
1435         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1436                 return 0; /* component must fit device */
1437         if (rdev->sb_start < rdev->data_offset) {
1438                 /* minor versions 1 and 2; superblock before data */
1439                 max_sectors = rdev->bdev->bd_inode->i_size >> 9;
1440                 max_sectors -= rdev->data_offset;
1441                 if (!num_sectors || num_sectors > max_sectors)
1442                         num_sectors = max_sectors;
1443         } else if (rdev->mddev->bitmap_offset) {
1444                 /* minor version 0 with bitmap we can't move */
1445                 return 0;
1446         } else {
1447                 /* minor version 0; superblock after data */
1448                 sector_t sb_start;
1449                 sb_start = (rdev->bdev->bd_inode->i_size >> 9) - 8*2;
1450                 sb_start &= ~(sector_t)(4*2 - 1);
1451                 max_sectors = rdev->sectors + sb_start - rdev->sb_start;
1452                 if (!num_sectors || num_sectors > max_sectors)
1453                         num_sectors = max_sectors;
1454                 rdev->sb_start = sb_start;
1455         }
1456         sb = (struct mdp_superblock_1 *) page_address(rdev->sb_page);
1457         sb->data_size = cpu_to_le64(num_sectors);
1458         sb->super_offset = rdev->sb_start;
1459         sb->sb_csum = calc_sb_1_csum(sb);
1460         md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1461                        rdev->sb_page);
1462         md_super_wait(rdev->mddev);
1463         return num_sectors / 2; /* kB for sysfs */
1464 }
1465
1466 static struct super_type super_types[] = {
1467         [0] = {
1468                 .name   = "0.90.0",
1469                 .owner  = THIS_MODULE,
1470                 .load_super         = super_90_load,
1471                 .validate_super     = super_90_validate,
1472                 .sync_super         = super_90_sync,
1473                 .rdev_size_change   = super_90_rdev_size_change,
1474         },
1475         [1] = {
1476                 .name   = "md-1",
1477                 .owner  = THIS_MODULE,
1478                 .load_super         = super_1_load,
1479                 .validate_super     = super_1_validate,
1480                 .sync_super         = super_1_sync,
1481                 .rdev_size_change   = super_1_rdev_size_change,
1482         },
1483 };
1484
1485 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1486 {
1487         mdk_rdev_t *rdev, *rdev2;
1488
1489         rcu_read_lock();
1490         rdev_for_each_rcu(rdev, mddev1)
1491                 rdev_for_each_rcu(rdev2, mddev2)
1492                         if (rdev->bdev->bd_contains ==
1493                             rdev2->bdev->bd_contains) {
1494                                 rcu_read_unlock();
1495                                 return 1;
1496                         }
1497         rcu_read_unlock();
1498         return 0;
1499 }
1500
1501 static LIST_HEAD(pending_raid_disks);
1502
1503 static void md_integrity_check(mdk_rdev_t *rdev, mddev_t *mddev)
1504 {
1505         struct mdk_personality *pers = mddev->pers;
1506         struct gendisk *disk = mddev->gendisk;
1507         struct blk_integrity *bi_rdev = bdev_get_integrity(rdev->bdev);
1508         struct blk_integrity *bi_mddev = blk_get_integrity(disk);
1509
1510         /* Data integrity passthrough not supported on RAID 4, 5 and 6 */
1511         if (pers && pers->level >= 4 && pers->level <= 6)
1512                 return;
1513
1514         /* If rdev is integrity capable, register profile for mddev */
1515         if (!bi_mddev && bi_rdev) {
1516                 if (blk_integrity_register(disk, bi_rdev))
1517                         printk(KERN_ERR "%s: %s Could not register integrity!\n",
1518                                __func__, disk->disk_name);
1519                 else
1520                         printk(KERN_NOTICE "Enabling data integrity on %s\n",
1521                                disk->disk_name);
1522                 return;
1523         }
1524
1525         /* Check that mddev and rdev have matching profiles */
1526         if (blk_integrity_compare(disk, rdev->bdev->bd_disk) < 0) {
1527                 printk(KERN_ERR "%s: %s/%s integrity mismatch!\n", __func__,
1528                        disk->disk_name, rdev->bdev->bd_disk->disk_name);
1529                 printk(KERN_NOTICE "Disabling data integrity on %s\n",
1530                        disk->disk_name);
1531                 blk_integrity_unregister(disk);
1532         }
1533 }
1534
1535 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1536 {
1537         char b[BDEVNAME_SIZE];
1538         struct kobject *ko;
1539         char *s;
1540         int err;
1541
1542         if (rdev->mddev) {
1543                 MD_BUG();
1544                 return -EINVAL;
1545         }
1546
1547         /* prevent duplicates */
1548         if (find_rdev(mddev, rdev->bdev->bd_dev))
1549                 return -EEXIST;
1550
1551         /* make sure rdev->sectors exceeds mddev->dev_sectors */
1552         if (rdev->sectors && (mddev->dev_sectors == 0 ||
1553                         rdev->sectors < mddev->dev_sectors)) {
1554                 if (mddev->pers) {
1555                         /* Cannot change size, so fail
1556                          * If mddev->level <= 0, then we don't care
1557                          * about aligning sizes (e.g. linear)
1558                          */
1559                         if (mddev->level > 0)
1560                                 return -ENOSPC;
1561                 } else
1562                         mddev->dev_sectors = rdev->sectors;
1563         }
1564
1565         /* Verify rdev->desc_nr is unique.
1566          * If it is -1, assign a free number, else
1567          * check number is not in use
1568          */
1569         if (rdev->desc_nr < 0) {
1570                 int choice = 0;
1571                 if (mddev->pers) choice = mddev->raid_disks;
1572                 while (find_rdev_nr(mddev, choice))
1573                         choice++;
1574                 rdev->desc_nr = choice;
1575         } else {
1576                 if (find_rdev_nr(mddev, rdev->desc_nr))
1577                         return -EBUSY;
1578         }
1579         if (mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
1580                 printk(KERN_WARNING "md: %s: array is limited to %d devices\n",
1581                        mdname(mddev), mddev->max_disks);
1582                 return -EBUSY;
1583         }
1584         bdevname(rdev->bdev,b);
1585         while ( (s=strchr(b, '/')) != NULL)
1586                 *s = '!';
1587
1588         rdev->mddev = mddev;
1589         printk(KERN_INFO "md: bind<%s>\n", b);
1590
1591         if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
1592                 goto fail;
1593
1594         ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
1595         if ((err = sysfs_create_link(&rdev->kobj, ko, "block"))) {
1596                 kobject_del(&rdev->kobj);
1597                 goto fail;
1598         }
1599         rdev->sysfs_state = sysfs_get_dirent(rdev->kobj.sd, "state");
1600
1601         list_add_rcu(&rdev->same_set, &mddev->disks);
1602         bd_claim_by_disk(rdev->bdev, rdev->bdev->bd_holder, mddev->gendisk);
1603
1604         /* May as well allow recovery to be retried once */
1605         mddev->recovery_disabled = 0;
1606
1607         md_integrity_check(rdev, mddev);
1608         return 0;
1609
1610  fail:
1611         printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
1612                b, mdname(mddev));
1613         return err;
1614 }
1615
1616 static void md_delayed_delete(struct work_struct *ws)
1617 {
1618         mdk_rdev_t *rdev = container_of(ws, mdk_rdev_t, del_work);
1619         kobject_del(&rdev->kobj);
1620         kobject_put(&rdev->kobj);
1621 }
1622
1623 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1624 {
1625         char b[BDEVNAME_SIZE];
1626         if (!rdev->mddev) {
1627                 MD_BUG();
1628                 return;
1629         }
1630         bd_release_from_disk(rdev->bdev, rdev->mddev->gendisk);
1631         list_del_rcu(&rdev->same_set);
1632         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1633         rdev->mddev = NULL;
1634         sysfs_remove_link(&rdev->kobj, "block");
1635         sysfs_put(rdev->sysfs_state);
1636         rdev->sysfs_state = NULL;
1637         /* We need to delay this, otherwise we can deadlock when
1638          * writing to 'remove' to "dev/state".  We also need
1639          * to delay it due to rcu usage.
1640          */
1641         synchronize_rcu();
1642         INIT_WORK(&rdev->del_work, md_delayed_delete);
1643         kobject_get(&rdev->kobj);
1644         schedule_work(&rdev->del_work);
1645 }
1646
1647 /*
1648  * prevent the device from being mounted, repartitioned or
1649  * otherwise reused by a RAID array (or any other kernel
1650  * subsystem), by bd_claiming the device.
1651  */
1652 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev, int shared)
1653 {
1654         int err = 0;
1655         struct block_device *bdev;
1656         char b[BDEVNAME_SIZE];
1657
1658         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1659         if (IS_ERR(bdev)) {
1660                 printk(KERN_ERR "md: could not open %s.\n",
1661                         __bdevname(dev, b));
1662                 return PTR_ERR(bdev);
1663         }
1664         err = bd_claim(bdev, shared ? (mdk_rdev_t *)lock_rdev : rdev);
1665         if (err) {
1666                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1667                         bdevname(bdev, b));
1668                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
1669                 return err;
1670         }
1671         if (!shared)
1672                 set_bit(AllReserved, &rdev->flags);
1673         rdev->bdev = bdev;
1674         return err;
1675 }
1676
1677 static void unlock_rdev(mdk_rdev_t *rdev)
1678 {
1679         struct block_device *bdev = rdev->bdev;
1680         rdev->bdev = NULL;
1681         if (!bdev)
1682                 MD_BUG();
1683         bd_release(bdev);
1684         blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
1685 }
1686
1687 void md_autodetect_dev(dev_t dev);
1688
1689 static void export_rdev(mdk_rdev_t * rdev)
1690 {
1691         char b[BDEVNAME_SIZE];
1692         printk(KERN_INFO "md: export_rdev(%s)\n",
1693                 bdevname(rdev->bdev,b));
1694         if (rdev->mddev)
1695                 MD_BUG();
1696         free_disk_sb(rdev);
1697 #ifndef MODULE
1698         if (test_bit(AutoDetected, &rdev->flags))
1699                 md_autodetect_dev(rdev->bdev->bd_dev);
1700 #endif
1701         unlock_rdev(rdev);
1702         kobject_put(&rdev->kobj);
1703 }
1704
1705 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1706 {
1707         unbind_rdev_from_array(rdev);
1708         export_rdev(rdev);
1709 }
1710
1711 static void export_array(mddev_t *mddev)
1712 {
1713         mdk_rdev_t *rdev, *tmp;
1714
1715         rdev_for_each(rdev, tmp, mddev) {
1716                 if (!rdev->mddev) {
1717                         MD_BUG();
1718                         continue;
1719                 }
1720                 kick_rdev_from_array(rdev);
1721         }
1722         if (!list_empty(&mddev->disks))
1723                 MD_BUG();
1724         mddev->raid_disks = 0;
1725         mddev->major_version = 0;
1726 }
1727
1728 static void print_desc(mdp_disk_t *desc)
1729 {
1730         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1731                 desc->major,desc->minor,desc->raid_disk,desc->state);
1732 }
1733
1734 static void print_sb_90(mdp_super_t *sb)
1735 {
1736         int i;
1737
1738         printk(KERN_INFO 
1739                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1740                 sb->major_version, sb->minor_version, sb->patch_version,
1741                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1742                 sb->ctime);
1743         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1744                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1745                 sb->md_minor, sb->layout, sb->chunk_size);
1746         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1747                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1748                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1749                 sb->failed_disks, sb->spare_disks,
1750                 sb->sb_csum, (unsigned long)sb->events_lo);
1751
1752         printk(KERN_INFO);
1753         for (i = 0; i < MD_SB_DISKS; i++) {
1754                 mdp_disk_t *desc;
1755
1756                 desc = sb->disks + i;
1757                 if (desc->number || desc->major || desc->minor ||
1758                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1759                         printk("     D %2d: ", i);
1760                         print_desc(desc);
1761                 }
1762         }
1763         printk(KERN_INFO "md:     THIS: ");
1764         print_desc(&sb->this_disk);
1765 }
1766
1767 static void print_sb_1(struct mdp_superblock_1 *sb)
1768 {
1769         __u8 *uuid;
1770
1771         uuid = sb->set_uuid;
1772         printk(KERN_INFO "md:  SB: (V:%u) (F:0x%08x) Array-ID:<%02x%02x%02x%02x"
1773                         ":%02x%02x:%02x%02x:%02x%02x:%02x%02x%02x%02x%02x%02x>\n"
1774                KERN_INFO "md:    Name: \"%s\" CT:%llu\n",
1775                 le32_to_cpu(sb->major_version),
1776                 le32_to_cpu(sb->feature_map),
1777                 uuid[0], uuid[1], uuid[2], uuid[3],
1778                 uuid[4], uuid[5], uuid[6], uuid[7],
1779                 uuid[8], uuid[9], uuid[10], uuid[11],
1780                 uuid[12], uuid[13], uuid[14], uuid[15],
1781                 sb->set_name,
1782                 (unsigned long long)le64_to_cpu(sb->ctime)
1783                        & MD_SUPERBLOCK_1_TIME_SEC_MASK);
1784
1785         uuid = sb->device_uuid;
1786         printk(KERN_INFO "md:       L%u SZ%llu RD:%u LO:%u CS:%u DO:%llu DS:%llu SO:%llu"
1787                         " RO:%llu\n"
1788                KERN_INFO "md:     Dev:%08x UUID: %02x%02x%02x%02x:%02x%02x:%02x%02x:%02x%02x"
1789                         ":%02x%02x%02x%02x%02x%02x\n"
1790                KERN_INFO "md:       (F:0x%08x) UT:%llu Events:%llu ResyncOffset:%llu CSUM:0x%08x\n"
1791                KERN_INFO "md:         (MaxDev:%u) \n",
1792                 le32_to_cpu(sb->level),
1793                 (unsigned long long)le64_to_cpu(sb->size),
1794                 le32_to_cpu(sb->raid_disks),
1795                 le32_to_cpu(sb->layout),
1796                 le32_to_cpu(sb->chunksize),
1797                 (unsigned long long)le64_to_cpu(sb->data_offset),
1798                 (unsigned long long)le64_to_cpu(sb->data_size),
1799                 (unsigned long long)le64_to_cpu(sb->super_offset),
1800                 (unsigned long long)le64_to_cpu(sb->recovery_offset),
1801                 le32_to_cpu(sb->dev_number),
1802                 uuid[0], uuid[1], uuid[2], uuid[3],
1803                 uuid[4], uuid[5], uuid[6], uuid[7],
1804                 uuid[8], uuid[9], uuid[10], uuid[11],
1805                 uuid[12], uuid[13], uuid[14], uuid[15],
1806                 sb->devflags,
1807                 (unsigned long long)le64_to_cpu(sb->utime) & MD_SUPERBLOCK_1_TIME_SEC_MASK,
1808                 (unsigned long long)le64_to_cpu(sb->events),
1809                 (unsigned long long)le64_to_cpu(sb->resync_offset),
1810                 le32_to_cpu(sb->sb_csum),
1811                 le32_to_cpu(sb->max_dev)
1812                 );
1813 }
1814
1815 static void print_rdev(mdk_rdev_t *rdev, int major_version)
1816 {
1817         char b[BDEVNAME_SIZE];
1818         printk(KERN_INFO "md: rdev %s, Sect:%08llu F:%d S:%d DN:%u\n",
1819                 bdevname(rdev->bdev, b), (unsigned long long)rdev->sectors,
1820                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1821                 rdev->desc_nr);
1822         if (rdev->sb_loaded) {
1823                 printk(KERN_INFO "md: rdev superblock (MJ:%d):\n", major_version);
1824                 switch (major_version) {
1825                 case 0:
1826                         print_sb_90((mdp_super_t*)page_address(rdev->sb_page));
1827                         break;
1828                 case 1:
1829                         print_sb_1((struct mdp_superblock_1 *)page_address(rdev->sb_page));
1830                         break;
1831                 }
1832         } else
1833                 printk(KERN_INFO "md: no rdev superblock!\n");
1834 }
1835
1836 static void md_print_devices(void)
1837 {
1838         struct list_head *tmp;
1839         mdk_rdev_t *rdev;
1840         mddev_t *mddev;
1841         char b[BDEVNAME_SIZE];
1842
1843         printk("\n");
1844         printk("md:     **********************************\n");
1845         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1846         printk("md:     **********************************\n");
1847         for_each_mddev(mddev, tmp) {
1848
1849                 if (mddev->bitmap)
1850                         bitmap_print_sb(mddev->bitmap);
1851                 else
1852                         printk("%s: ", mdname(mddev));
1853                 list_for_each_entry(rdev, &mddev->disks, same_set)
1854                         printk("<%s>", bdevname(rdev->bdev,b));
1855                 printk("\n");
1856
1857                 list_for_each_entry(rdev, &mddev->disks, same_set)
1858                         print_rdev(rdev, mddev->major_version);
1859         }
1860         printk("md:     **********************************\n");
1861         printk("\n");
1862 }
1863
1864
1865 static void sync_sbs(mddev_t * mddev, int nospares)
1866 {
1867         /* Update each superblock (in-memory image), but
1868          * if we are allowed to, skip spares which already
1869          * have the right event counter, or have one earlier
1870          * (which would mean they aren't being marked as dirty
1871          * with the rest of the array)
1872          */
1873         mdk_rdev_t *rdev;
1874
1875         list_for_each_entry(rdev, &mddev->disks, same_set) {
1876                 if (rdev->sb_events == mddev->events ||
1877                     (nospares &&
1878                      rdev->raid_disk < 0 &&
1879                      (rdev->sb_events&1)==0 &&
1880                      rdev->sb_events+1 == mddev->events)) {
1881                         /* Don't update this superblock */
1882                         rdev->sb_loaded = 2;
1883                 } else {
1884                         super_types[mddev->major_version].
1885                                 sync_super(mddev, rdev);
1886                         rdev->sb_loaded = 1;
1887                 }
1888         }
1889 }
1890
1891 static void md_update_sb(mddev_t * mddev, int force_change)
1892 {
1893         mdk_rdev_t *rdev;
1894         int sync_req;
1895         int nospares = 0;
1896
1897         if (mddev->external)
1898                 return;
1899 repeat:
1900         spin_lock_irq(&mddev->write_lock);
1901
1902         set_bit(MD_CHANGE_PENDING, &mddev->flags);
1903         if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
1904                 force_change = 1;
1905         if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
1906                 /* just a clean<-> dirty transition, possibly leave spares alone,
1907                  * though if events isn't the right even/odd, we will have to do
1908                  * spares after all
1909                  */
1910                 nospares = 1;
1911         if (force_change)
1912                 nospares = 0;
1913         if (mddev->degraded)
1914                 /* If the array is degraded, then skipping spares is both
1915                  * dangerous and fairly pointless.
1916                  * Dangerous because a device that was removed from the array
1917                  * might have a event_count that still looks up-to-date,
1918                  * so it can be re-added without a resync.
1919                  * Pointless because if there are any spares to skip,
1920                  * then a recovery will happen and soon that array won't
1921                  * be degraded any more and the spare can go back to sleep then.
1922                  */
1923                 nospares = 0;
1924
1925         sync_req = mddev->in_sync;
1926         mddev->utime = get_seconds();
1927
1928         /* If this is just a dirty<->clean transition, and the array is clean
1929          * and 'events' is odd, we can roll back to the previous clean state */
1930         if (nospares
1931             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
1932             && (mddev->events & 1)
1933             && mddev->events != 1)
1934                 mddev->events--;
1935         else {
1936                 /* otherwise we have to go forward and ... */
1937                 mddev->events ++;
1938                 if (!mddev->in_sync || mddev->recovery_cp != MaxSector) { /* not clean */
1939                         /* .. if the array isn't clean, insist on an odd 'events' */
1940                         if ((mddev->events&1)==0) {
1941                                 mddev->events++;
1942                                 nospares = 0;
1943                         }
1944                 } else {
1945                         /* otherwise insist on an even 'events' (for clean states) */
1946                         if ((mddev->events&1)) {
1947                                 mddev->events++;
1948                                 nospares = 0;
1949                         }
1950                 }
1951         }
1952
1953         if (!mddev->events) {
1954                 /*
1955                  * oops, this 64-bit counter should never wrap.
1956                  * Either we are in around ~1 trillion A.C., assuming
1957                  * 1 reboot per second, or we have a bug:
1958                  */
1959                 MD_BUG();
1960                 mddev->events --;
1961         }
1962
1963         /*
1964          * do not write anything to disk if using
1965          * nonpersistent superblocks
1966          */
1967         if (!mddev->persistent) {
1968                 if (!mddev->external)
1969                         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
1970
1971                 spin_unlock_irq(&mddev->write_lock);
1972                 wake_up(&mddev->sb_wait);
1973                 return;
1974         }
1975         sync_sbs(mddev, nospares);
1976         spin_unlock_irq(&mddev->write_lock);
1977
1978         dprintk(KERN_INFO 
1979                 "md: updating %s RAID superblock on device (in sync %d)\n",
1980                 mdname(mddev),mddev->in_sync);
1981
1982         bitmap_update_sb(mddev->bitmap);
1983         list_for_each_entry(rdev, &mddev->disks, same_set) {
1984                 char b[BDEVNAME_SIZE];
1985                 dprintk(KERN_INFO "md: ");
1986                 if (rdev->sb_loaded != 1)
1987                         continue; /* no noise on spare devices */
1988                 if (test_bit(Faulty, &rdev->flags))
1989                         dprintk("(skipping faulty ");
1990
1991                 dprintk("%s ", bdevname(rdev->bdev,b));
1992                 if (!test_bit(Faulty, &rdev->flags)) {
1993                         md_super_write(mddev,rdev,
1994                                        rdev->sb_start, rdev->sb_size,
1995                                        rdev->sb_page);
1996                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1997                                 bdevname(rdev->bdev,b),
1998                                 (unsigned long long)rdev->sb_start);
1999                         rdev->sb_events = mddev->events;
2000
2001                 } else
2002                         dprintk(")\n");
2003                 if (mddev->level == LEVEL_MULTIPATH)
2004                         /* only need to write one superblock... */
2005                         break;
2006         }
2007         md_super_wait(mddev);
2008         /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
2009
2010         spin_lock_irq(&mddev->write_lock);
2011         if (mddev->in_sync != sync_req ||
2012             test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
2013                 /* have to write it out again */
2014                 spin_unlock_irq(&mddev->write_lock);
2015                 goto repeat;
2016         }
2017         clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2018         spin_unlock_irq(&mddev->write_lock);
2019         wake_up(&mddev->sb_wait);
2020         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2021                 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
2022
2023 }
2024
2025 /* words written to sysfs files may, or may not, be \n terminated.
2026  * We want to accept with case. For this we use cmd_match.
2027  */
2028 static int cmd_match(const char *cmd, const char *str)
2029 {
2030         /* See if cmd, written into a sysfs file, matches
2031          * str.  They must either be the same, or cmd can
2032          * have a trailing newline
2033          */
2034         while (*cmd && *str && *cmd == *str) {
2035                 cmd++;
2036                 str++;
2037         }
2038         if (*cmd == '\n')
2039                 cmd++;
2040         if (*str || *cmd)
2041                 return 0;
2042         return 1;
2043 }
2044
2045 struct rdev_sysfs_entry {
2046         struct attribute attr;
2047         ssize_t (*show)(mdk_rdev_t *, char *);
2048         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
2049 };
2050
2051 static ssize_t
2052 state_show(mdk_rdev_t *rdev, char *page)
2053 {
2054         char *sep = "";
2055         size_t len = 0;
2056
2057         if (test_bit(Faulty, &rdev->flags)) {
2058                 len+= sprintf(page+len, "%sfaulty",sep);
2059                 sep = ",";
2060         }
2061         if (test_bit(In_sync, &rdev->flags)) {
2062                 len += sprintf(page+len, "%sin_sync",sep);
2063                 sep = ",";
2064         }
2065         if (test_bit(WriteMostly, &rdev->flags)) {
2066                 len += sprintf(page+len, "%swrite_mostly",sep);
2067                 sep = ",";
2068         }
2069         if (test_bit(Blocked, &rdev->flags)) {
2070                 len += sprintf(page+len, "%sblocked", sep);
2071                 sep = ",";
2072         }
2073         if (!test_bit(Faulty, &rdev->flags) &&
2074             !test_bit(In_sync, &rdev->flags)) {
2075                 len += sprintf(page+len, "%sspare", sep);
2076                 sep = ",";
2077         }
2078         return len+sprintf(page+len, "\n");
2079 }
2080
2081 static ssize_t
2082 state_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2083 {
2084         /* can write
2085          *  faulty  - simulates and error
2086          *  remove  - disconnects the device
2087          *  writemostly - sets write_mostly
2088          *  -writemostly - clears write_mostly
2089          *  blocked - sets the Blocked flag
2090          *  -blocked - clears the Blocked flag
2091          *  insync - sets Insync providing device isn't active
2092          */
2093         int err = -EINVAL;
2094         if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2095                 md_error(rdev->mddev, rdev);
2096                 err = 0;
2097         } else if (cmd_match(buf, "remove")) {
2098                 if (rdev->raid_disk >= 0)
2099                         err = -EBUSY;
2100                 else {
2101                         mddev_t *mddev = rdev->mddev;
2102                         kick_rdev_from_array(rdev);
2103                         if (mddev->pers)
2104                                 md_update_sb(mddev, 1);
2105                         md_new_event(mddev);
2106                         err = 0;
2107                 }
2108         } else if (cmd_match(buf, "writemostly")) {
2109                 set_bit(WriteMostly, &rdev->flags);
2110                 err = 0;
2111         } else if (cmd_match(buf, "-writemostly")) {
2112                 clear_bit(WriteMostly, &rdev->flags);
2113                 err = 0;
2114         } else if (cmd_match(buf, "blocked")) {
2115                 set_bit(Blocked, &rdev->flags);
2116                 err = 0;
2117         } else if (cmd_match(buf, "-blocked")) {
2118                 clear_bit(Blocked, &rdev->flags);
2119                 wake_up(&rdev->blocked_wait);
2120                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2121                 md_wakeup_thread(rdev->mddev->thread);
2122
2123                 err = 0;
2124         } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
2125                 set_bit(In_sync, &rdev->flags);
2126                 err = 0;
2127         }
2128         if (!err && rdev->sysfs_state)
2129                 sysfs_notify_dirent(rdev->sysfs_state);
2130         return err ? err : len;
2131 }
2132 static struct rdev_sysfs_entry rdev_state =
2133 __ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
2134
2135 static ssize_t
2136 errors_show(mdk_rdev_t *rdev, char *page)
2137 {
2138         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
2139 }
2140
2141 static ssize_t
2142 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2143 {
2144         char *e;
2145         unsigned long n = simple_strtoul(buf, &e, 10);
2146         if (*buf && (*e == 0 || *e == '\n')) {
2147                 atomic_set(&rdev->corrected_errors, n);
2148                 return len;
2149         }
2150         return -EINVAL;
2151 }
2152 static struct rdev_sysfs_entry rdev_errors =
2153 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
2154
2155 static ssize_t
2156 slot_show(mdk_rdev_t *rdev, char *page)
2157 {
2158         if (rdev->raid_disk < 0)
2159                 return sprintf(page, "none\n");
2160         else
2161                 return sprintf(page, "%d\n", rdev->raid_disk);
2162 }
2163
2164 static ssize_t
2165 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2166 {
2167         char *e;
2168         int err;
2169         char nm[20];
2170         int slot = simple_strtoul(buf, &e, 10);
2171         if (strncmp(buf, "none", 4)==0)
2172                 slot = -1;
2173         else if (e==buf || (*e && *e!= '\n'))
2174                 return -EINVAL;
2175         if (rdev->mddev->pers && slot == -1) {
2176                 /* Setting 'slot' on an active array requires also
2177                  * updating the 'rd%d' link, and communicating
2178                  * with the personality with ->hot_*_disk.
2179                  * For now we only support removing
2180                  * failed/spare devices.  This normally happens automatically,
2181                  * but not when the metadata is externally managed.
2182                  */
2183                 if (rdev->raid_disk == -1)
2184                         return -EEXIST;
2185                 /* personality does all needed checks */
2186                 if (rdev->mddev->pers->hot_add_disk == NULL)
2187                         return -EINVAL;
2188                 err = rdev->mddev->pers->
2189                         hot_remove_disk(rdev->mddev, rdev->raid_disk);
2190                 if (err)
2191                         return err;
2192                 sprintf(nm, "rd%d", rdev->raid_disk);
2193                 sysfs_remove_link(&rdev->mddev->kobj, nm);
2194                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2195                 md_wakeup_thread(rdev->mddev->thread);
2196         } else if (rdev->mddev->pers) {
2197                 mdk_rdev_t *rdev2;
2198                 /* Activating a spare .. or possibly reactivating
2199                  * if we ever get bitmaps working here.
2200                  */
2201
2202                 if (rdev->raid_disk != -1)
2203                         return -EBUSY;
2204
2205                 if (rdev->mddev->pers->hot_add_disk == NULL)
2206                         return -EINVAL;
2207
2208                 list_for_each_entry(rdev2, &rdev->mddev->disks, same_set)
2209                         if (rdev2->raid_disk == slot)
2210                                 return -EEXIST;
2211
2212                 rdev->raid_disk = slot;
2213                 if (test_bit(In_sync, &rdev->flags))
2214                         rdev->saved_raid_disk = slot;
2215                 else
2216                         rdev->saved_raid_disk = -1;
2217                 err = rdev->mddev->pers->
2218                         hot_add_disk(rdev->mddev, rdev);
2219                 if (err) {
2220                         rdev->raid_disk = -1;
2221                         return err;
2222                 } else
2223                         sysfs_notify_dirent(rdev->sysfs_state);
2224                 sprintf(nm, "rd%d", rdev->raid_disk);
2225                 if (sysfs_create_link(&rdev->mddev->kobj, &rdev->kobj, nm))
2226                         printk(KERN_WARNING
2227                                "md: cannot register "
2228                                "%s for %s\n",
2229                                nm, mdname(rdev->mddev));
2230
2231                 /* don't wakeup anyone, leave that to userspace. */
2232         } else {
2233                 if (slot >= rdev->mddev->raid_disks)
2234                         return -ENOSPC;
2235                 rdev->raid_disk = slot;
2236                 /* assume it is working */
2237                 clear_bit(Faulty, &rdev->flags);
2238                 clear_bit(WriteMostly, &rdev->flags);
2239                 set_bit(In_sync, &rdev->flags);
2240                 sysfs_notify_dirent(rdev->sysfs_state);
2241         }
2242         return len;
2243 }
2244
2245
2246 static struct rdev_sysfs_entry rdev_slot =
2247 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
2248
2249 static ssize_t
2250 offset_show(mdk_rdev_t *rdev, char *page)
2251 {
2252         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
2253 }
2254
2255 static ssize_t
2256 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2257 {
2258         char *e;
2259         unsigned long long offset = simple_strtoull(buf, &e, 10);
2260         if (e==buf || (*e && *e != '\n'))
2261                 return -EINVAL;
2262         if (rdev->mddev->pers && rdev->raid_disk >= 0)
2263                 return -EBUSY;
2264         if (rdev->sectors && rdev->mddev->external)
2265                 /* Must set offset before size, so overlap checks
2266                  * can be sane */
2267                 return -EBUSY;
2268         rdev->data_offset = offset;
2269         return len;
2270 }
2271
2272 static struct rdev_sysfs_entry rdev_offset =
2273 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
2274
2275 static ssize_t
2276 rdev_size_show(mdk_rdev_t *rdev, char *page)
2277 {
2278         return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
2279 }
2280
2281 static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
2282 {
2283         /* check if two start/length pairs overlap */
2284         if (s1+l1 <= s2)
2285                 return 0;
2286         if (s2+l2 <= s1)
2287                 return 0;
2288         return 1;
2289 }
2290
2291 static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
2292 {
2293         unsigned long long blocks;
2294         sector_t new;
2295
2296         if (strict_strtoull(buf, 10, &blocks) < 0)
2297                 return -EINVAL;
2298
2299         if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
2300                 return -EINVAL; /* sector conversion overflow */
2301
2302         new = blocks * 2;
2303         if (new != blocks * 2)
2304                 return -EINVAL; /* unsigned long long to sector_t overflow */
2305
2306         *sectors = new;
2307         return 0;
2308 }
2309
2310 static ssize_t
2311 rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
2312 {
2313         mddev_t *my_mddev = rdev->mddev;
2314         sector_t oldsectors = rdev->sectors;
2315         sector_t sectors;
2316
2317         if (strict_blocks_to_sectors(buf, &sectors) < 0)
2318                 return -EINVAL;
2319         if (my_mddev->pers && rdev->raid_disk >= 0) {
2320                 if (my_mddev->persistent) {
2321                         sectors = super_types[my_mddev->major_version].
2322                                 rdev_size_change(rdev, sectors);
2323                         if (!sectors)
2324                                 return -EBUSY;
2325                 } else if (!sectors)
2326                         sectors = (rdev->bdev->bd_inode->i_size >> 9) -
2327                                 rdev->data_offset;
2328         }
2329         if (sectors < my_mddev->dev_sectors)
2330                 return -EINVAL; /* component must fit device */
2331
2332         rdev->sectors = sectors;
2333         if (sectors > oldsectors && my_mddev->external) {
2334                 /* need to check that all other rdevs with the same ->bdev
2335                  * do not overlap.  We need to unlock the mddev to avoid
2336                  * a deadlock.  We have already changed rdev->sectors, and if
2337                  * we have to change it back, we will have the lock again.
2338                  */
2339                 mddev_t *mddev;
2340                 int overlap = 0;
2341                 struct list_head *tmp;
2342
2343                 mddev_unlock(my_mddev);
2344                 for_each_mddev(mddev, tmp) {
2345                         mdk_rdev_t *rdev2;
2346
2347                         mddev_lock(mddev);
2348                         list_for_each_entry(rdev2, &mddev->disks, same_set)
2349                                 if (test_bit(AllReserved, &rdev2->flags) ||
2350                                     (rdev->bdev == rdev2->bdev &&
2351                                      rdev != rdev2 &&
2352                                      overlaps(rdev->data_offset, rdev->sectors,
2353                                               rdev2->data_offset,
2354                                               rdev2->sectors))) {
2355                                         overlap = 1;
2356                                         break;
2357                                 }
2358                         mddev_unlock(mddev);
2359                         if (overlap) {
2360                                 mddev_put(mddev);
2361                                 break;
2362                         }
2363                 }
2364                 mddev_lock(my_mddev);
2365                 if (overlap) {
2366                         /* Someone else could have slipped in a size
2367                          * change here, but doing so is just silly.
2368                          * We put oldsectors back because we *know* it is
2369                          * safe, and trust userspace not to race with
2370                          * itself
2371                          */
2372                         rdev->sectors = oldsectors;
2373                         return -EBUSY;
2374                 }
2375         }
2376         return len;
2377 }
2378
2379 static struct rdev_sysfs_entry rdev_size =
2380 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
2381
2382 static struct attribute *rdev_default_attrs[] = {
2383         &rdev_state.attr,
2384         &rdev_errors.attr,
2385         &rdev_slot.attr,
2386         &rdev_offset.attr,
2387         &rdev_size.attr,
2388         NULL,
2389 };
2390 static ssize_t
2391 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2392 {
2393         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2394         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2395         mddev_t *mddev = rdev->mddev;
2396         ssize_t rv;
2397
2398         if (!entry->show)
2399                 return -EIO;
2400
2401         rv = mddev ? mddev_lock(mddev) : -EBUSY;
2402         if (!rv) {
2403                 if (rdev->mddev == NULL)
2404                         rv = -EBUSY;
2405                 else
2406                         rv = entry->show(rdev, page);
2407                 mddev_unlock(mddev);
2408         }
2409         return rv;
2410 }
2411
2412 static ssize_t
2413 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
2414               const char *page, size_t length)
2415 {
2416         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
2417         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
2418         ssize_t rv;
2419         mddev_t *mddev = rdev->mddev;
2420
2421         if (!entry->store)
2422                 return -EIO;
2423         if (!capable(CAP_SYS_ADMIN))
2424                 return -EACCES;
2425         rv = mddev ? mddev_lock(mddev): -EBUSY;
2426         if (!rv) {
2427                 if (rdev->mddev == NULL)
2428                         rv = -EBUSY;
2429                 else
2430                         rv = entry->store(rdev, page, length);
2431                 mddev_unlock(mddev);
2432         }
2433         return rv;
2434 }
2435
2436 static void rdev_free(struct kobject *ko)
2437 {
2438         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
2439         kfree(rdev);
2440 }
2441 static struct sysfs_ops rdev_sysfs_ops = {
2442         .show           = rdev_attr_show,
2443         .store          = rdev_attr_store,
2444 };
2445 static struct kobj_type rdev_ktype = {
2446         .release        = rdev_free,
2447         .sysfs_ops      = &rdev_sysfs_ops,
2448         .default_attrs  = rdev_default_attrs,
2449 };
2450
2451 /*
2452  * Import a device. If 'super_format' >= 0, then sanity check the superblock
2453  *
2454  * mark the device faulty if:
2455  *
2456  *   - the device is nonexistent (zero size)
2457  *   - the device has no valid superblock
2458  *
2459  * a faulty rdev _never_ has rdev->sb set.
2460  */
2461 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
2462 {
2463         char b[BDEVNAME_SIZE];
2464         int err;
2465         mdk_rdev_t *rdev;
2466         sector_t size;
2467
2468         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
2469         if (!rdev) {
2470                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
2471                 return ERR_PTR(-ENOMEM);
2472         }
2473
2474         if ((err = alloc_disk_sb(rdev)))
2475                 goto abort_free;
2476
2477         err = lock_rdev(rdev, newdev, super_format == -2);
2478         if (err)
2479                 goto abort_free;
2480
2481         kobject_init(&rdev->kobj, &rdev_ktype);
2482
2483         rdev->desc_nr = -1;
2484         rdev->saved_raid_disk = -1;
2485         rdev->raid_disk = -1;
2486         rdev->flags = 0;
2487         rdev->data_offset = 0;
2488         rdev->sb_events = 0;
2489         atomic_set(&rdev->nr_pending, 0);
2490         atomic_set(&rdev->read_errors, 0);
2491         atomic_set(&rdev->corrected_errors, 0);
2492
2493         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
2494         if (!size) {
2495                 printk(KERN_WARNING 
2496                         "md: %s has zero or unknown size, marking faulty!\n",
2497                         bdevname(rdev->bdev,b));
2498                 err = -EINVAL;
2499                 goto abort_free;
2500         }
2501
2502         if (super_format >= 0) {
2503                 err = super_types[super_format].
2504                         load_super(rdev, NULL, super_minor);
2505                 if (err == -EINVAL) {
2506                         printk(KERN_WARNING
2507                                 "md: %s does not have a valid v%d.%d "
2508                                "superblock, not importing!\n",
2509                                 bdevname(rdev->bdev,b),
2510                                super_format, super_minor);
2511                         goto abort_free;
2512                 }
2513                 if (err < 0) {
2514                         printk(KERN_WARNING 
2515                                 "md: could not read %s's sb, not importing!\n",
2516                                 bdevname(rdev->bdev,b));
2517                         goto abort_free;
2518                 }
2519         }
2520
2521         INIT_LIST_HEAD(&rdev->same_set);
2522         init_waitqueue_head(&rdev->blocked_wait);
2523
2524         return rdev;
2525
2526 abort_free:
2527         if (rdev->sb_page) {
2528                 if (rdev->bdev)
2529                         unlock_rdev(rdev);
2530                 free_disk_sb(rdev);
2531         }
2532         kfree(rdev);
2533         return ERR_PTR(err);
2534 }
2535
2536 /*
2537  * Check a full RAID array for plausibility
2538  */
2539
2540
2541 static void analyze_sbs(mddev_t * mddev)
2542 {
2543         int i;
2544         mdk_rdev_t *rdev, *freshest, *tmp;
2545         char b[BDEVNAME_SIZE];
2546
2547         freshest = NULL;
2548         rdev_for_each(rdev, tmp, mddev)
2549                 switch (super_types[mddev->major_version].
2550                         load_super(rdev, freshest, mddev->minor_version)) {
2551                 case 1:
2552                         freshest = rdev;
2553                         break;
2554                 case 0:
2555                         break;
2556                 default:
2557                         printk( KERN_ERR \
2558                                 "md: fatal superblock inconsistency in %s"
2559                                 " -- removing from array\n", 
2560                                 bdevname(rdev->bdev,b));
2561                         kick_rdev_from_array(rdev);
2562                 }
2563
2564
2565         super_types[mddev->major_version].
2566                 validate_super(mddev, freshest);
2567
2568         i = 0;
2569         rdev_for_each(rdev, tmp, mddev) {
2570                 if (rdev->desc_nr >= mddev->max_disks ||
2571                     i > mddev->max_disks) {
2572                         printk(KERN_WARNING
2573                                "md: %s: %s: only %d devices permitted\n",
2574                                mdname(mddev), bdevname(rdev->bdev, b),
2575                                mddev->max_disks);
2576                         kick_rdev_from_array(rdev);
2577                         continue;
2578                 }
2579                 if (rdev != freshest)
2580                         if (super_types[mddev->major_version].
2581                             validate_super(mddev, rdev)) {
2582                                 printk(KERN_WARNING "md: kicking non-fresh %s"
2583                                         " from array!\n",
2584                                         bdevname(rdev->bdev,b));
2585                                 kick_rdev_from_array(rdev);
2586                                 continue;
2587                         }
2588                 if (mddev->level == LEVEL_MULTIPATH) {
2589                         rdev->desc_nr = i++;
2590                         rdev->raid_disk = rdev->desc_nr;
2591                         set_bit(In_sync, &rdev->flags);
2592                 } else if (rdev->raid_disk >= mddev->raid_disks) {
2593                         rdev->raid_disk = -1;
2594                         clear_bit(In_sync, &rdev->flags);
2595                 }
2596         }
2597
2598
2599
2600         if (mddev->recovery_cp != MaxSector &&
2601             mddev->level >= 1)
2602                 printk(KERN_ERR "md: %s: raid array is not clean"
2603                        " -- starting background reconstruction\n",
2604                        mdname(mddev));
2605
2606 }
2607
2608 static void md_safemode_timeout(unsigned long data);
2609
2610 static ssize_t
2611 safe_delay_show(mddev_t *mddev, char *page)
2612 {
2613         int msec = (mddev->safemode_delay*1000)/HZ;
2614         return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
2615 }
2616 static ssize_t
2617 safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
2618 {
2619         int scale=1;
2620         int dot=0;
2621         int i;
2622         unsigned long msec;
2623         char buf[30];
2624
2625         /* remove a period, and count digits after it */
2626         if (len >= sizeof(buf))
2627                 return -EINVAL;
2628         strlcpy(buf, cbuf, sizeof(buf));
2629         for (i=0; i<len; i++) {
2630                 if (dot) {
2631                         if (isdigit(buf[i])) {
2632                                 buf[i-1] = buf[i];
2633                                 scale *= 10;
2634                         }
2635                         buf[i] = 0;
2636                 } else if (buf[i] == '.') {
2637                         dot=1;
2638                         buf[i] = 0;
2639                 }
2640         }
2641         if (strict_strtoul(buf, 10, &msec) < 0)
2642                 return -EINVAL;
2643         msec = (msec * 1000) / scale;
2644         if (msec == 0)
2645                 mddev->safemode_delay = 0;
2646         else {
2647                 unsigned long old_delay = mddev->safemode_delay;
2648                 mddev->safemode_delay = (msec*HZ)/1000;
2649                 if (mddev->safemode_delay == 0)
2650                         mddev->safemode_delay = 1;
2651                 if (mddev->safemode_delay < old_delay)
2652                         md_safemode_timeout((unsigned long)mddev);
2653         }
2654         return len;
2655 }
2656 static struct md_sysfs_entry md_safe_delay =
2657 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
2658
2659 static ssize_t
2660 level_show(mddev_t *mddev, char *page)
2661 {
2662         struct mdk_personality *p = mddev->pers;
2663         if (p)
2664                 return sprintf(page, "%s\n", p->name);
2665         else if (mddev->clevel[0])
2666                 return sprintf(page, "%s\n", mddev->clevel);
2667         else if (mddev->level != LEVEL_NONE)
2668                 return sprintf(page, "%d\n", mddev->level);
2669         else
2670                 return 0;
2671 }
2672
2673 static ssize_t
2674 level_store(mddev_t *mddev, const char *buf, size_t len)
2675 {
2676         char level[16];
2677         ssize_t rv = len;
2678         struct mdk_personality *pers;
2679         void *priv;
2680
2681         if (mddev->pers == NULL) {
2682                 if (len == 0)
2683                         return 0;
2684                 if (len >= sizeof(mddev->clevel))
2685                         return -ENOSPC;
2686                 strncpy(mddev->clevel, buf, len);
2687                 if (mddev->clevel[len-1] == '\n')
2688                         len--;
2689                 mddev->clevel[len] = 0;
2690                 mddev->level = LEVEL_NONE;
2691                 return rv;
2692         }
2693
2694         /* request to change the personality.  Need to ensure:
2695          *  - array is not engaged in resync/recovery/reshape
2696          *  - old personality can be suspended
2697          *  - new personality will access other array.
2698          */
2699
2700         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
2701                 return -EBUSY;
2702
2703         if (!mddev->pers->quiesce) {
2704                 printk(KERN_WARNING "md: %s: %s does not support online personality change\n",
2705                        mdname(mddev), mddev->pers->name);
2706                 return -EINVAL;
2707         }
2708
2709         /* Now find the new personality */
2710         if (len == 0 || len >= sizeof(level))
2711                 return -EINVAL;
2712         strncpy(level, buf, len);
2713         if (level[len-1] == '\n')
2714                 len--;
2715         level[len] = 0;
2716
2717         request_module("md-%s", level);
2718         spin_lock(&pers_lock);
2719         pers = find_pers(LEVEL_NONE, level);
2720         if (!pers || !try_module_get(pers->owner)) {
2721                 spin_unlock(&pers_lock);
2722                 printk(KERN_WARNING "md: personality %s not loaded\n", level);
2723                 return -EINVAL;
2724         }
2725         spin_unlock(&pers_lock);
2726
2727         if (pers == mddev->pers) {
2728                 /* Nothing to do! */
2729                 module_put(pers->owner);
2730                 return rv;
2731         }
2732         if (!pers->takeover) {
2733                 module_put(pers->owner);
2734                 printk(KERN_WARNING "md: %s: %s does not support personality takeover\n",
2735                        mdname(mddev), level);
2736                 return -EINVAL;
2737         }
2738
2739         /* ->takeover must set new_* and/or delta_disks
2740          * if it succeeds, and may set them when it fails.
2741          */
2742         priv = pers->takeover(mddev);
2743         if (IS_ERR(priv)) {
2744                 mddev->new_level = mddev->level;
2745                 mddev->new_layout = mddev->layout;
2746                 mddev->new_chunk = mddev->chunk_size;
2747                 mddev->raid_disks -= mddev->delta_disks;
2748                 mddev->delta_disks = 0;
2749                 module_put(pers->owner);
2750                 printk(KERN_WARNING "md: %s: %s would not accept array\n",
2751                        mdname(mddev), level);
2752                 return PTR_ERR(priv);
2753         }
2754
2755         /* Looks like we have a winner */
2756         mddev_suspend(mddev);
2757         mddev->pers->stop(mddev);
2758         module_put(mddev->pers->owner);
2759         mddev->pers = pers;
2760         mddev->private = priv;
2761         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
2762         mddev->level = mddev->new_level;
2763         mddev->layout = mddev->new_layout;
2764         mddev->chunk_size = mddev->new_chunk;
2765         mddev->delta_disks = 0;
2766         pers->run(mddev);
2767         mddev_resume(mddev);
2768         set_bit(MD_CHANGE_DEVS, &mddev->flags);
2769         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2770         md_wakeup_thread(mddev->thread);
2771         return rv;
2772 }
2773
2774 static struct md_sysfs_entry md_level =
2775 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
2776
2777
2778 static ssize_t
2779 layout_show(mddev_t *mddev, char *page)
2780 {
2781         /* just a number, not meaningful for all levels */
2782         if (mddev->reshape_position != MaxSector &&
2783             mddev->layout != mddev->new_layout)
2784                 return sprintf(page, "%d (%d)\n",
2785                                mddev->new_layout, mddev->layout);
2786         return sprintf(page, "%d\n", mddev->layout);
2787 }
2788
2789 static ssize_t
2790 layout_store(mddev_t *mddev, const char *buf, size_t len)
2791 {
2792         char *e;
2793         unsigned long n = simple_strtoul(buf, &e, 10);
2794
2795         if (!*buf || (*e && *e != '\n'))
2796                 return -EINVAL;
2797
2798         if (mddev->pers) {
2799                 int err;
2800                 if (mddev->pers->reconfig == NULL)
2801                         return -EBUSY;
2802                 err = mddev->pers->reconfig(mddev, n, -1);
2803                 if (err)
2804                         return err;
2805         } else {
2806                 mddev->new_layout = n;
2807                 if (mddev->reshape_position == MaxSector)
2808                         mddev->layout = n;
2809         }
2810         return len;
2811 }
2812 static struct md_sysfs_entry md_layout =
2813 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
2814
2815
2816 static ssize_t
2817 raid_disks_show(mddev_t *mddev, char *page)
2818 {
2819         if (mddev->raid_disks == 0)
2820                 return 0;
2821         if (mddev->reshape_position != MaxSector &&
2822             mddev->delta_disks != 0)
2823                 return sprintf(page, "%d (%d)\n", mddev->raid_disks,
2824                                mddev->raid_disks - mddev->delta_disks);
2825         return sprintf(page, "%d\n", mddev->raid_disks);
2826 }
2827
2828 static int update_raid_disks(mddev_t *mddev, int raid_disks);
2829
2830 static ssize_t
2831 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
2832 {
2833         char *e;
2834         int rv = 0;
2835         unsigned long n = simple_strtoul(buf, &e, 10);
2836
2837         if (!*buf || (*e && *e != '\n'))
2838                 return -EINVAL;
2839
2840         if (mddev->pers)
2841                 rv = update_raid_disks(mddev, n);
2842         else if (mddev->reshape_position != MaxSector) {
2843                 int olddisks = mddev->raid_disks - mddev->delta_disks;
2844                 mddev->delta_disks = n - olddisks;
2845                 mddev->raid_disks = n;
2846         } else
2847                 mddev->raid_disks = n;
2848         return rv ? rv : len;
2849 }
2850 static struct md_sysfs_entry md_raid_disks =
2851 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
2852
2853 static ssize_t
2854 chunk_size_show(mddev_t *mddev, char *page)
2855 {
2856         if (mddev->reshape_position != MaxSector &&
2857             mddev->chunk_size != mddev->new_chunk)
2858                 return sprintf(page, "%d (%d)\n", mddev->new_chunk,
2859                                mddev->chunk_size);
2860         return sprintf(page, "%d\n", mddev->chunk_size);
2861 }
2862
2863 static ssize_t
2864 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
2865 {
2866         char *e;
2867         unsigned long n = simple_strtoul(buf, &e, 10);
2868
2869         if (!*buf || (*e && *e != '\n'))
2870                 return -EINVAL;
2871
2872         if (mddev->pers) {
2873                 int err;
2874                 if (mddev->pers->reconfig == NULL)
2875                         return -EBUSY;
2876                 err = mddev->pers->reconfig(mddev, -1, n);
2877                 if (err)
2878                         return err;
2879         } else {
2880                 mddev->new_chunk = n;
2881                 if (mddev->reshape_position == MaxSector)
2882                         mddev->chunk_size = n;
2883         }
2884         return len;
2885 }
2886 static struct md_sysfs_entry md_chunk_size =
2887 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
2888
2889 static ssize_t
2890 resync_start_show(mddev_t *mddev, char *page)
2891 {
2892         if (mddev->recovery_cp == MaxSector)
2893                 return sprintf(page, "none\n");
2894         return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
2895 }
2896
2897 static ssize_t
2898 resync_start_store(mddev_t *mddev, const char *buf, size_t len)
2899 {
2900         char *e;
2901         unsigned long long n = simple_strtoull(buf, &e, 10);
2902
2903         if (mddev->pers)
2904                 return -EBUSY;
2905         if (!*buf || (*e && *e != '\n'))
2906                 return -EINVAL;
2907
2908         mddev->recovery_cp = n;
2909         return len;
2910 }
2911 static struct md_sysfs_entry md_resync_start =
2912 __ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
2913
2914 /*
2915  * The array state can be:
2916  *
2917  * clear
2918  *     No devices, no size, no level
2919  *     Equivalent to STOP_ARRAY ioctl
2920  * inactive
2921  *     May have some settings, but array is not active
2922  *        all IO results in error
2923  *     When written, doesn't tear down array, but just stops it
2924  * suspended (not supported yet)
2925  *     All IO requests will block. The array can be reconfigured.
2926  *     Writing this, if accepted, will block until array is quiescent
2927  * readonly
2928  *     no resync can happen.  no superblocks get written.
2929  *     write requests fail
2930  * read-auto
2931  *     like readonly, but behaves like 'clean' on a write request.
2932  *
2933  * clean - no pending writes, but otherwise active.
2934  *     When written to inactive array, starts without resync
2935  *     If a write request arrives then
2936  *       if metadata is known, mark 'dirty' and switch to 'active'.
2937  *       if not known, block and switch to write-pending
2938  *     If written to an active array that has pending writes, then fails.
2939  * active
2940  *     fully active: IO and resync can be happening.
2941  *     When written to inactive array, starts with resync
2942  *
2943  * write-pending
2944  *     clean, but writes are blocked waiting for 'active' to be written.
2945  *
2946  * active-idle
2947  *     like active, but no writes have been seen for a while (100msec).
2948  *
2949  */
2950 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
2951                    write_pending, active_idle, bad_word};
2952 static char *array_states[] = {
2953         "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
2954         "write-pending", "active-idle", NULL };
2955
2956 static int match_word(const char *word, char **list)
2957 {
2958         int n;
2959         for (n=0; list[n]; n++)
2960                 if (cmd_match(word, list[n]))
2961                         break;
2962         return n;
2963 }
2964
2965 static ssize_t
2966 array_state_show(mddev_t *mddev, char *page)
2967 {
2968         enum array_state st = inactive;
2969
2970         if (mddev->pers)
2971                 switch(mddev->ro) {
2972                 case 1:
2973                         st = readonly;
2974                         break;
2975                 case 2:
2976                         st = read_auto;
2977                         break;
2978                 case 0:
2979                         if (mddev->in_sync)
2980                                 st = clean;
2981                         else if (test_bit(MD_CHANGE_CLEAN, &mddev->flags))
2982                                 st = write_pending;
2983                         else if (mddev->safemode)
2984                                 st = active_idle;
2985                         else
2986                                 st = active;
2987                 }
2988         else {
2989                 if (list_empty(&mddev->disks) &&
2990                     mddev->raid_disks == 0 &&
2991                     mddev->dev_sectors == 0)
2992                         st = clear;
2993                 else
2994                         st = inactive;
2995         }
2996         return sprintf(page, "%s\n", array_states[st]);
2997 }
2998
2999 static int do_md_stop(mddev_t * mddev, int ro, int is_open);
3000 static int do_md_run(mddev_t * mddev);
3001 static int restart_array(mddev_t *mddev);
3002
3003 static ssize_t
3004 array_state_store(mddev_t *mddev, const char *buf, size_t len)
3005 {
3006         int err = -EINVAL;
3007         enum array_state st = match_word(buf, array_states);
3008         switch(st) {
3009         case bad_word:
3010                 break;
3011         case clear:
3012                 /* stopping an active array */
3013                 if (atomic_read(&mddev->openers) > 0)
3014                         return -EBUSY;
3015                 err = do_md_stop(mddev, 0, 0);
3016                 break;
3017         case inactive:
3018                 /* stopping an active array */
3019                 if (mddev->pers) {
3020                         if (atomic_read(&mddev->openers) > 0)
3021                                 return -EBUSY;
3022                         err = do_md_stop(mddev, 2, 0);
3023                 } else
3024                         err = 0; /* already inactive */
3025                 break;
3026         case suspended:
3027                 break; /* not supported yet */
3028         case readonly:
3029                 if (mddev->pers)
3030                         err = do_md_stop(mddev, 1, 0);
3031                 else {
3032                         mddev->ro = 1;
3033                         set_disk_ro(mddev->gendisk, 1);
3034                         err = do_md_run(mddev);
3035                 }
3036                 break;
3037         case read_auto:
3038                 if (mddev->pers) {
3039                         if (mddev->ro == 0)
3040                                 err = do_md_stop(mddev, 1, 0);
3041                         else if (mddev->ro == 1)
3042                                 err = restart_array(mddev);
3043                         if (err == 0) {
3044                                 mddev->ro = 2;
3045                                 set_disk_ro(mddev->gendisk, 0);
3046                         }
3047                 } else {
3048                         mddev->ro = 2;
3049                         err = do_md_run(mddev);
3050                 }
3051                 break;
3052         case clean:
3053                 if (mddev->pers) {
3054                         restart_array(mddev);
3055                         spin_lock_irq(&mddev->write_lock);
3056                         if (atomic_read(&mddev->writes_pending) == 0) {
3057                                 if (mddev->in_sync == 0) {
3058                                         mddev->in_sync = 1;
3059                                         if (mddev->safemode == 1)
3060                                                 mddev->safemode = 0;
3061                                         if (mddev->persistent)
3062                                                 set_bit(MD_CHANGE_CLEAN,
3063                                                         &mddev->flags);
3064                                 }
3065                                 err = 0;
3066                         } else
3067                                 err = -EBUSY;
3068                         spin_unlock_irq(&mddev->write_lock);
3069                 } else
3070                         err = -EINVAL;
3071                 break;
3072         case active:
3073                 if (mddev->pers) {
3074                         restart_array(mddev);
3075                         if (mddev->external)
3076                                 clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
3077                         wake_up(&mddev->sb_wait);
3078                         err = 0;
3079                 } else {
3080                         mddev->ro = 0;
3081                         set_disk_ro(mddev->gendisk, 0);
3082                         err = do_md_run(mddev);
3083                 }
3084                 break;
3085         case write_pending:
3086         case active_idle:
3087                 /* these cannot be set */
3088                 break;
3089         }
3090         if (err)
3091                 return err;
3092         else {
3093                 sysfs_notify_dirent(mddev->sysfs_state);
3094                 return len;
3095         }
3096 }
3097 static struct md_sysfs_entry md_array_state =
3098 __ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
3099
3100 static ssize_t
3101 null_show(mddev_t *mddev, char *page)
3102 {
3103         return -EINVAL;
3104 }
3105
3106 static ssize_t
3107 new_dev_store(mddev_t *mddev, const char *buf, size_t len)
3108 {
3109         /* buf must be %d:%d\n? giving major and minor numbers */
3110         /* The new device is added to the array.
3111          * If the array has a persistent superblock, we read the
3112          * superblock to initialise info and check validity.
3113          * Otherwise, only checking done is that in bind_rdev_to_array,
3114          * which mainly checks size.
3115          */
3116         char *e;
3117         int major = simple_strtoul(buf, &e, 10);
3118         int minor;
3119         dev_t dev;
3120         mdk_rdev_t *rdev;
3121         int err;
3122
3123         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
3124                 return -EINVAL;
3125         minor = simple_strtoul(e+1, &e, 10);
3126         if (*e && *e != '\n')
3127                 return -EINVAL;
3128         dev = MKDEV(major, minor);
3129         if (major != MAJOR(dev) ||
3130             minor != MINOR(dev))
3131                 return -EOVERFLOW;
3132
3133
3134         if (mddev->persistent) {
3135                 rdev = md_import_device(dev, mddev->major_version,
3136                                         mddev->minor_version);
3137                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
3138                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
3139                                                        mdk_rdev_t, same_set);
3140                         err = super_types[mddev->major_version]
3141                                 .load_super(rdev, rdev0, mddev->minor_version);
3142                         if (err < 0)
3143                                 goto out;
3144                 }
3145         } else if (mddev->external)
3146                 rdev = md_import_device(dev, -2, -1);
3147         else
3148                 rdev = md_import_device(dev, -1, -1);
3149
3150         if (IS_ERR(rdev))
3151                 return PTR_ERR(rdev);
3152         err = bind_rdev_to_array(rdev, mddev);
3153  out:
3154         if (err)
3155                 export_rdev(rdev);
3156         return err ? err : len;
3157 }
3158
3159 static struct md_sysfs_entry md_new_device =
3160 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
3161
3162 static ssize_t
3163 bitmap_store(mddev_t *mddev, const char *buf, size_t len)
3164 {
3165         char *end;
3166         unsigned long chunk, end_chunk;
3167
3168         if (!mddev->bitmap)
3169                 goto out;
3170         /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
3171         while (*buf) {
3172                 chunk = end_chunk = simple_strtoul(buf, &end, 0);
3173                 if (buf == end) break;
3174                 if (*end == '-') { /* range */
3175                         buf = end + 1;
3176                         end_chunk = simple_strtoul(buf, &end, 0);
3177                         if (buf == end) break;
3178                 }
3179                 if (*end && !isspace(*end)) break;
3180                 bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
3181                 buf = end;
3182                 while (isspace(*buf)) buf++;
3183         }
3184         bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
3185 out:
3186         return len;
3187 }
3188
3189 static struct md_sysfs_entry md_bitmap =
3190 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
3191
3192 static ssize_t
3193 size_show(mddev_t *mddev, char *page)
3194 {
3195         return sprintf(page, "%llu\n",
3196                 (unsigned long long)mddev->dev_sectors / 2);
3197 }
3198
3199 static int update_size(mddev_t *mddev, sector_t num_sectors);
3200
3201 static ssize_t
3202 size_store(mddev_t *mddev, const char *buf, size_t len)
3203 {
3204         /* If array is inactive, we can reduce the component size, but
3205          * not increase it (except from 0).
3206          * If array is active, we can try an on-line resize
3207          */
3208         sector_t sectors;
3209         int err = strict_blocks_to_sectors(buf, &sectors);
3210
3211         if (err < 0)
3212                 return err;
3213         if (mddev->pers) {
3214                 err = update_size(mddev, sectors);
3215                 md_update_sb(mddev, 1);
3216         } else {
3217                 if (mddev->dev_sectors == 0 ||
3218                     mddev->dev_sectors > sectors)
3219                         mddev->dev_sectors = sectors;
3220                 else
3221                         err = -ENOSPC;
3222         }
3223         return err ? err : len;
3224 }
3225
3226 static struct md_sysfs_entry md_size =
3227 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
3228
3229
3230 /* Metdata version.
3231  * This is one of
3232  *   'none' for arrays with no metadata (good luck...)
3233  *   'external' for arrays with externally managed metadata,
3234  * or N.M for internally known formats
3235  */
3236 static ssize_t
3237 metadata_show(mddev_t *mddev, char *page)
3238 {
3239         if (mddev->persistent)
3240                 return sprintf(page, "%d.%d\n",
3241                                mddev->major_version, mddev->minor_version);
3242         else if (mddev->external)
3243                 return sprintf(page, "external:%s\n", mddev->metadata_type);
3244         else
3245                 return sprintf(page, "none\n");
3246 }
3247
3248 static ssize_t
3249 metadata_store(mddev_t *mddev, const char *buf, size_t len)
3250 {
3251         int major, minor;
3252         char *e;
3253         /* Changing the details of 'external' metadata is
3254          * always permitted.  Otherwise there must be
3255          * no devices attached to the array.
3256          */
3257         if (mddev->external && strncmp(buf, "external:", 9) == 0)
3258                 ;
3259         else if (!list_empty(&mddev->disks))
3260                 return -EBUSY;
3261
3262         if (cmd_match(buf, "none")) {
3263                 mddev->persistent = 0;
3264                 mddev->external = 0;
3265                 mddev->major_version = 0;
3266                 mddev->minor_version = 90;
3267                 return len;
3268         }
3269         if (strncmp(buf, "external:", 9) == 0) {
3270                 size_t namelen = len-9;
3271                 if (namelen >= sizeof(mddev->metadata_type))
3272                         namelen = sizeof(mddev->metadata_type)-1;
3273                 strncpy(mddev->metadata_type, buf+9, namelen);
3274                 mddev->metadata_type[namelen] = 0;
3275                 if (namelen && mddev->metadata_type[namelen-1] == '\n')
3276                         mddev->metadata_type[--namelen] = 0;
3277                 mddev->persistent = 0;
3278                 mddev->external = 1;
3279                 mddev->major_version = 0;
3280                 mddev->minor_version = 90;
3281                 return len;
3282         }
3283         major = simple_strtoul(buf, &e, 10);
3284         if (e==buf || *e != '.')
3285                 return -EINVAL;
3286         buf = e+1;
3287         minor = simple_strtoul(buf, &e, 10);
3288         if (e==buf || (*e && *e != '\n') )
3289                 return -EINVAL;
3290         if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
3291                 return -ENOENT;
3292         mddev->major_version = major;
3293         mddev->minor_version = minor;
3294         mddev->persistent = 1;
3295         mddev->external = 0;
3296         return len;
3297 }
3298
3299 static struct md_sysfs_entry md_metadata =
3300 __ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
3301
3302 static ssize_t
3303 action_show(mddev_t *mddev, char *page)
3304 {
3305         char *type = "idle";
3306         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3307             (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
3308                 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
3309                         type = "reshape";
3310                 else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
3311                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
3312                                 type = "resync";
3313                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
3314                                 type = "check";
3315                         else
3316                                 type = "repair";
3317                 } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
3318                         type = "recover";
3319         }
3320         return sprintf(page, "%s\n", type);
3321 }
3322
3323 static ssize_t
3324 action_store(mddev_t *mddev, const char *page, size_t len)
3325 {
3326         if (!mddev->pers || !mddev->pers->sync_request)
3327                 return -EINVAL;
3328
3329         if (cmd_match(page, "idle")) {
3330                 if (mddev->sync_thread) {
3331                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3332                         md_unregister_thread(mddev->sync_thread);
3333                         mddev->sync_thread = NULL;
3334                         mddev->recovery = 0;
3335                 }
3336         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3337                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
3338                 return -EBUSY;
3339         else if (cmd_match(page, "resync"))
3340                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3341         else if (cmd_match(page, "recover")) {
3342                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3343                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3344         } else if (cmd_match(page, "reshape")) {
3345                 int err;
3346                 if (mddev->pers->start_reshape == NULL)
3347                         return -EINVAL;
3348                 err = mddev->pers->start_reshape(mddev);
3349                 if (err)
3350                         return err;
3351                 sysfs_notify(&mddev->kobj, NULL, "degraded");
3352         } else {
3353                 if (cmd_match(page, "check"))
3354                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3355                 else if (!cmd_match(page, "repair"))
3356                         return -EINVAL;
3357                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3358                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3359         }
3360         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3361         md_wakeup_thread(mddev->thread);
3362         sysfs_notify_dirent(mddev->sysfs_action);
3363         return len;
3364 }
3365
3366 static ssize_t
3367 mismatch_cnt_show(mddev_t *mddev, char *page)
3368 {
3369         return sprintf(page, "%llu\n",
3370                        (unsigned long long) mddev->resync_mismatches);
3371 }
3372
3373 static struct md_sysfs_entry md_scan_mode =
3374 __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
3375
3376
3377 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
3378
3379 static ssize_t
3380 sync_min_show(mddev_t *mddev, char *page)
3381 {
3382         return sprintf(page, "%d (%s)\n", speed_min(mddev),
3383                        mddev->sync_speed_min ? "local": "system");
3384 }
3385
3386 static ssize_t
3387 sync_min_store(mddev_t *mddev, const char *buf, size_t len)
3388 {
3389         int min;
3390         char *e;
3391         if (strncmp(buf, "system", 6)==0) {
3392                 mddev->sync_speed_min = 0;
3393                 return len;
3394         }
3395         min = simple_strtoul(buf, &e, 10);
3396         if (buf == e || (*e && *e != '\n') || min <= 0)
3397                 return -EINVAL;
3398         mddev->sync_speed_min = min;
3399         return len;
3400 }
3401
3402 static struct md_sysfs_entry md_sync_min =
3403 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
3404
3405 static ssize_t
3406 sync_max_show(mddev_t *mddev, char *page)
3407 {
3408         return sprintf(page, "%d (%s)\n", speed_max(mddev),
3409                        mddev->sync_speed_max ? "local": "system");
3410 }
3411
3412 static ssize_t
3413 sync_max_store(mddev_t *mddev, const char *buf, size_t len)
3414 {
3415         int max;
3416         char *e;
3417         if (strncmp(buf, "system", 6)==0) {
3418                 mddev->sync_speed_max = 0;
3419                 return len;
3420         }
3421         max = simple_strtoul(buf, &e, 10);
3422         if (buf == e || (*e && *e != '\n') || max <= 0)
3423                 return -EINVAL;
3424         mddev->sync_speed_max = max;
3425         return len;
3426 }
3427
3428 static struct md_sysfs_entry md_sync_max =
3429 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
3430
3431 static ssize_t
3432 degraded_show(mddev_t *mddev, char *page)
3433 {
3434         return sprintf(page, "%d\n", mddev->degraded);
3435 }
3436 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
3437
3438 static ssize_t
3439 sync_force_parallel_show(mddev_t *mddev, char *page)
3440 {
3441         return sprintf(page, "%d\n", mddev->parallel_resync);
3442 }
3443
3444 static ssize_t
3445 sync_force_parallel_store(mddev_t *mddev, const char *buf, size_t len)
3446 {
3447         long n;
3448
3449         if (strict_strtol(buf, 10, &n))
3450                 return -EINVAL;
3451
3452         if (n != 0 && n != 1)
3453                 return -EINVAL;
3454
3455         mddev->parallel_resync = n;
3456
3457         if (mddev->sync_thread)
3458                 wake_up(&resync_wait);
3459
3460         return len;
3461 }
3462
3463 /* force parallel resync, even with shared block devices */
3464 static struct md_sysfs_entry md_sync_force_parallel =
3465 __ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
3466        sync_force_parallel_show, sync_force_parallel_store);
3467
3468 static ssize_t
3469 sync_speed_show(mddev_t *mddev, char *page)
3470 {
3471         unsigned long resync, dt, db;
3472         if (mddev->curr_resync == 0)
3473                 return sprintf(page, "none\n");
3474         resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
3475         dt = (jiffies - mddev->resync_mark) / HZ;
3476         if (!dt) dt++;
3477         db = resync - mddev->resync_mark_cnt;
3478         return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
3479 }
3480
3481 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
3482
3483 static ssize_t
3484 sync_completed_show(mddev_t *mddev, char *page)
3485 {
3486         unsigned long max_sectors, resync;
3487
3488         if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3489                 return sprintf(page, "none\n");
3490
3491         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
3492                 max_sectors = mddev->resync_max_sectors;
3493         else
3494                 max_sectors = mddev->dev_sectors;
3495
3496         resync = mddev->curr_resync_completed;
3497         return sprintf(page, "%lu / %lu\n", resync, max_sectors);
3498 }
3499
3500 static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
3501
3502 static ssize_t
3503 min_sync_show(mddev_t *mddev, char *page)
3504 {
3505         return sprintf(page, "%llu\n",
3506                        (unsigned long long)mddev->resync_min);
3507 }
3508 static ssize_t
3509 min_sync_store(mddev_t *mddev, const char *buf, size_t len)
3510 {
3511         unsigned long long min;
3512         if (strict_strtoull(buf, 10, &min))
3513                 return -EINVAL;
3514         if (min > mddev->resync_max)
3515                 return -EINVAL;
3516         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3517                 return -EBUSY;
3518
3519         /* Must be a multiple of chunk_size */
3520         if (mddev->chunk_size) {
3521                 if (min & (sector_t)((mddev->chunk_size>>9)-1))
3522                         return -EINVAL;
3523         }
3524         mddev->resync_min = min;
3525
3526         return len;
3527 }
3528
3529 static struct md_sysfs_entry md_min_sync =
3530 __ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
3531
3532 static ssize_t
3533 max_sync_show(mddev_t *mddev, char *page)
3534 {
3535         if (mddev->resync_max == MaxSector)
3536                 return sprintf(page, "max\n");
3537         else
3538                 return sprintf(page, "%llu\n",
3539                                (unsigned long long)mddev->resync_max);
3540 }
3541 static ssize_t
3542 max_sync_store(mddev_t *mddev, const char *buf, size_t len)
3543 {
3544         if (strncmp(buf, "max", 3) == 0)
3545                 mddev->resync_max = MaxSector;
3546         else {
3547                 unsigned long long max;
3548                 if (strict_strtoull(buf, 10, &max))
3549                         return -EINVAL;
3550                 if (max < mddev->resync_min)
3551                         return -EINVAL;
3552                 if (max < mddev->resync_max &&
3553                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3554                         return -EBUSY;
3555
3556                 /* Must be a multiple of chunk_size */
3557                 if (mddev->chunk_size) {
3558                         if (max & (sector_t)((mddev->chunk_size>>9)-1))
3559                                 return -EINVAL;
3560                 }
3561                 mddev->resync_max = max;
3562         }
3563         wake_up(&mddev->recovery_wait);
3564         return len;
3565 }
3566
3567 static struct md_sysfs_entry md_max_sync =
3568 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
3569
3570 static ssize_t
3571 suspend_lo_show(mddev_t *mddev, char *page)
3572 {
3573         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
3574 }
3575
3576 static ssize_t
3577 suspend_lo_store(mddev_t *mddev, const char *buf, size_t len)
3578 {
3579         char *e;
3580         unsigned long long new = simple_strtoull(buf, &e, 10);
3581
3582         if (mddev->pers->quiesce == NULL)
3583                 return -EINVAL;
3584         if (buf == e || (*e && *e != '\n'))
3585                 return -EINVAL;
3586         if (new >= mddev->suspend_hi ||
3587             (new > mddev->suspend_lo && new < mddev->suspend_hi)) {
3588                 mddev->suspend_lo = new;
3589                 mddev->pers->quiesce(mddev, 2);
3590                 return len;
3591         } else
3592                 return -EINVAL;
3593 }
3594 static struct md_sysfs_entry md_suspend_lo =
3595 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
3596
3597
3598 static ssize_t
3599 suspend_hi_show(mddev_t *mddev, char *page)
3600 {
3601         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
3602 }
3603
3604 static ssize_t
3605 suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
3606 {
3607         char *e;
3608         unsigned long long new = simple_strtoull(buf, &e, 10);
3609
3610         if (mddev->pers->quiesce == NULL)
3611                 return -EINVAL;
3612         if (buf == e || (*e && *e != '\n'))
3613                 return -EINVAL;
3614         if ((new <= mddev->suspend_lo && mddev->suspend_lo >= mddev->suspend_hi) ||
3615             (new > mddev->suspend_lo && new > mddev->suspend_hi)) {
3616                 mddev->suspend_hi = new;
3617                 mddev->pers->quiesce(mddev, 1);
3618                 mddev->pers->quiesce(mddev, 0);
3619                 return len;
3620         } else
3621                 return -EINVAL;
3622 }
3623 static struct md_sysfs_entry md_suspend_hi =
3624 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
3625
3626 static ssize_t
3627 reshape_position_show(mddev_t *mddev, char *page)
3628 {
3629         if (mddev->reshape_position != MaxSector)
3630                 return sprintf(page, "%llu\n",
3631                                (unsigned long long)mddev->reshape_position);
3632         strcpy(page, "none\n");
3633         return 5;
3634 }
3635
3636 static ssize_t
3637 reshape_position_store(mddev_t *mddev, const char *buf, size_t len)
3638 {
3639         char *e;
3640         unsigned long long new = simple_strtoull(buf, &e, 10);
3641         if (mddev->pers)
3642                 return -EBUSY;
3643         if (buf == e || (*e && *e != '\n'))
3644                 return -EINVAL;
3645         mddev->reshape_position = new;
3646         mddev->delta_disks = 0;
3647         mddev->new_level = mddev->level;
3648         mddev->new_layout = mddev->layout;
3649         mddev->new_chunk = mddev->chunk_size;
3650         return len;
3651 }
3652
3653 static struct md_sysfs_entry md_reshape_position =
3654 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
3655        reshape_position_store);
3656
3657 static ssize_t
3658 array_size_show(mddev_t *mddev, char *page)
3659 {
3660         if (mddev->external_size)
3661                 return sprintf(page, "%llu\n",
3662                                (unsigned long long)mddev->array_sectors/2);
3663         else
3664                 return sprintf(page, "default\n");
3665 }
3666
3667 static ssize_t
3668 array_size_store(mddev_t *mddev, const char *buf, size_t len)
3669 {
3670         sector_t sectors;
3671
3672         if (strncmp(buf, "default", 7) == 0) {
3673                 if (mddev->pers)
3674                         sectors = mddev->pers->size(mddev, 0, 0);
3675                 else
3676                         sectors = mddev->array_sectors;
3677
3678                 mddev->external_size = 0;
3679         } else {
3680                 if (strict_blocks_to_sectors(buf, &sectors) < 0)
3681                         return -EINVAL;
3682                 if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
3683                         return -EINVAL;
3684
3685                 mddev->external_size = 1;
3686         }
3687
3688         mddev->array_sectors = sectors;
3689         set_capacity(mddev->gendisk, mddev->array_sectors);
3690         if (mddev->pers) {
3691                 struct block_device *bdev = bdget_disk(mddev->gendisk, 0);
3692
3693                 if (bdev) {
3694                         mutex_lock(&bdev->bd_inode->i_mutex);
3695                         i_size_write(bdev->bd_inode,
3696                                      (loff_t)mddev->array_sectors << 9);
3697                         mutex_unlock(&bdev->bd_inode->i_mutex);
3698                         bdput(bdev);
3699                 }
3700         }
3701
3702         return len;
3703 }
3704
3705 static struct md_sysfs_entry md_array_size =
3706 __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
3707        array_size_store);
3708
3709 static struct attribute *md_default_attrs[] = {
3710         &md_level.attr,
3711         &md_layout.attr,
3712         &md_raid_disks.attr,
3713         &md_chunk_size.attr,
3714         &md_size.attr,
3715         &md_resync_start.attr,
3716         &md_metadata.attr,
3717         &md_new_device.attr,
3718         &md_safe_delay.attr,
3719         &md_array_state.attr,
3720         &md_reshape_position.attr,
3721         &md_array_size.attr,
3722         NULL,
3723 };
3724
3725 static struct attribute *md_redundancy_attrs[] = {
3726         &md_scan_mode.attr,
3727         &md_mismatches.attr,
3728         &md_sync_min.attr,
3729         &md_sync_max.attr,
3730         &md_sync_speed.attr,
3731         &md_sync_force_parallel.attr,
3732         &md_sync_completed.attr,
3733         &md_min_sync.attr,
3734         &md_max_sync.attr,
3735         &md_suspend_lo.attr,
3736         &md_suspend_hi.attr,
3737         &md_bitmap.attr,
3738         &md_degraded.attr,
3739         NULL,
3740 };
3741 static struct attribute_group md_redundancy_group = {
3742         .name = NULL,
3743         .attrs = md_redundancy_attrs,
3744 };
3745
3746
3747 static ssize_t
3748 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3749 {
3750         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3751         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3752         ssize_t rv;
3753
3754         if (!entry->show)
3755                 return -EIO;
3756         rv = mddev_lock(mddev);
3757         if (!rv) {
3758                 rv = entry->show(mddev, page);
3759                 mddev_unlock(mddev);
3760         }
3761         return rv;
3762 }
3763
3764 static ssize_t
3765 md_attr_store(struct kobject *kobj, struct attribute *attr,
3766               const char *page, size_t length)
3767 {
3768         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
3769         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
3770         ssize_t rv;
3771
3772         if (!entry->store)
3773                 return -EIO;
3774         if (!capable(CAP_SYS_ADMIN))
3775                 return -EACCES;
3776         rv = mddev_lock(mddev);
3777         if (mddev->hold_active == UNTIL_IOCTL)
3778                 mddev->hold_active = 0;
3779         if (!rv) {
3780                 rv = entry->store(mddev, page, length);
3781                 mddev_unlock(mddev);
3782         }
3783         return rv;
3784 }
3785
3786 static void md_free(struct kobject *ko)
3787 {
3788         mddev_t *mddev = container_of(ko, mddev_t, kobj);
3789
3790         if (mddev->sysfs_state)
3791                 sysfs_put(mddev->sysfs_state);
3792
3793         if (mddev->gendisk) {
3794                 del_gendisk(mddev->gendisk);
3795                 put_disk(mddev->gendisk);
3796         }
3797         if (mddev->queue)
3798                 blk_cleanup_queue(mddev->queue);
3799
3800         kfree(mddev);
3801 }
3802
3803 static struct sysfs_ops md_sysfs_ops = {
3804         .show   = md_attr_show,
3805         .store  = md_attr_store,
3806 };
3807 static struct kobj_type md_ktype = {
3808         .release        = md_free,
3809         .sysfs_ops      = &md_sysfs_ops,
3810         .default_attrs  = md_default_attrs,
3811 };
3812
3813 int mdp_major = 0;
3814
3815 static void mddev_delayed_delete(struct work_struct *ws)
3816 {
3817         mddev_t *mddev = container_of(ws, mddev_t, del_work);
3818
3819         if (mddev->private == &md_redundancy_group) {
3820                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
3821                 if (mddev->sysfs_action)
3822                         sysfs_put(mddev->sysfs_action);
3823                 mddev->sysfs_action = NULL;
3824                 mddev->private = NULL;
3825         }
3826         kobject_del(&mddev->kobj);
3827         kobject_put(&mddev->kobj);
3828 }
3829
3830 static int md_alloc(dev_t dev, char *name)
3831 {
3832         static DEFINE_MUTEX(disks_mutex);
3833         mddev_t *mddev = mddev_find(dev);
3834         struct gendisk *disk;
3835         int partitioned;
3836         int shift;
3837         int unit;
3838         int error;
3839
3840         if (!mddev)
3841                 return -ENODEV;
3842
3843         partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
3844         shift = partitioned ? MdpMinorShift : 0;
3845         unit = MINOR(mddev->unit) >> shift;
3846
3847         /* wait for any previous instance if this device
3848          * to be completed removed (mddev_delayed_delete).
3849          */
3850         flush_scheduled_work();
3851
3852         mutex_lock(&disks_mutex);
3853         if (mddev->gendisk) {
3854                 mutex_unlock(&disks_mutex);
3855                 mddev_put(mddev);
3856                 return -EEXIST;
3857         }
3858
3859         if (name) {
3860                 /* Need to ensure that 'name' is not a duplicate.
3861                  */
3862                 mddev_t *mddev2;
3863                 spin_lock(&all_mddevs_lock);
3864
3865                 list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
3866                         if (mddev2->gendisk &&
3867                             strcmp(mddev2->gendisk->disk_name, name) == 0) {
3868                                 spin_unlock(&all_mddevs_lock);
3869                                 return -EEXIST;
3870                         }
3871                 spin_unlock(&all_mddevs_lock);
3872         }
3873
3874         mddev->queue = blk_alloc_queue(GFP_KERNEL);
3875         if (!mddev->queue) {
3876                 mutex_unlock(&disks_mutex);
3877                 mddev_put(mddev);
3878                 return -ENOMEM;
3879         }
3880         mddev->queue->queuedata = mddev;
3881
3882         /* Can be unlocked because the queue is new: no concurrency */
3883         queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, mddev->queue);
3884
3885         blk_queue_make_request(mddev->queue, md_make_request);
3886
3887         disk = alloc_disk(1 << shift);
3888         if (!disk) {
3889                 mutex_unlock(&disks_mutex);
3890                 blk_cleanup_queue(mddev->queue);
3891                 mddev->queue = NULL;
3892                 mddev_put(mddev);
3893                 return -ENOMEM;
3894         }
3895         disk->major = MAJOR(mddev->unit);
3896         disk->first_minor = unit << shift;
3897         if (name)
3898                 strcpy(disk->disk_name, name);
3899         else if (partitioned)
3900                 sprintf(disk->disk_name, "md_d%d", unit);
3901         else
3902                 sprintf(disk->disk_name, "md%d", unit);
3903         disk->fops = &md_fops;
3904         disk->private_data = mddev;
3905         disk->queue = mddev->queue;
3906         /* Allow extended partitions.  This makes the
3907          * 'mdp' device redundant, but we can't really
3908          * remove it now.
3909          */
3910         disk->flags |= GENHD_FL_EXT_DEVT;
3911         add_disk(disk);
3912         mddev->gendisk = disk;
3913         error = kobject_init_and_add(&mddev->kobj, &md_ktype,
3914                                      &disk_to_dev(disk)->kobj, "%s", "md");
3915         mutex_unlock(&disks_mutex);
3916         if (error)
3917                 printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
3918                        disk->disk_name);
3919         else {
3920                 kobject_uevent(&mddev->kobj, KOBJ_ADD);
3921                 mddev->sysfs_state = sysfs_get_dirent(mddev->kobj.sd, "array_state");
3922         }
3923         mddev_put(mddev);
3924         return 0;
3925 }
3926
3927 static struct kobject *md_probe(dev_t dev, int *part, void *data)
3928 {
3929         md_alloc(dev, NULL);
3930         return NULL;
3931 }
3932
3933 static int add_named_array(const char *val, struct kernel_param *kp)
3934 {
3935         /* val must be "md_*" where * is not all digits.
3936          * We allocate an array with a large free minor number, and
3937          * set the name to val.  val must not already be an active name.
3938          */
3939         int len = strlen(val);
3940         char buf[DISK_NAME_LEN];
3941
3942         while (len && val[len-1] == '\n')
3943                 len--;
3944         if (len >= DISK_NAME_LEN)
3945                 return -E2BIG;
3946         strlcpy(buf, val, len+1);
3947         if (strncmp(buf, "md_", 3) != 0)
3948                 return -EINVAL;
3949         return md_alloc(0, buf);
3950 }
3951
3952 static void md_safemode_timeout(unsigned long data)
3953 {
3954         mddev_t *mddev = (mddev_t *) data;
3955
3956         if (!atomic_read(&mddev->writes_pending)) {
3957                 mddev->safemode = 1;
3958                 if (mddev->external)
3959                         sysfs_notify_dirent(mddev->sysfs_state);
3960         }
3961         md_wakeup_thread(mddev->thread);
3962 }
3963
3964 static int start_dirty_degraded;
3965
3966 static int do_md_run(mddev_t * mddev)
3967 {
3968         int err;
3969         int chunk_size;
3970         mdk_rdev_t *rdev;
3971         struct gendisk *disk;
3972         struct mdk_personality *pers;
3973         char b[BDEVNAME_SIZE];
3974
3975         if (list_empty(&mddev->disks))
3976                 /* cannot run an array with no devices.. */
3977                 return -EINVAL;
3978
3979         if (mddev->pers)
3980                 return -EBUSY;
3981
3982         /*
3983          * Analyze all RAID superblock(s)
3984          */
3985         if (!mddev->raid_disks) {
3986                 if (!mddev->persistent)
3987                         return -EINVAL;
3988                 analyze_sbs(mddev);
3989         }
3990
3991         chunk_size = mddev->chunk_size;
3992
3993         if (chunk_size) {
3994                 if (chunk_size > MAX_CHUNK_SIZE) {
3995                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
3996                                 chunk_size, MAX_CHUNK_SIZE);
3997                         return -EINVAL;
3998                 }
3999                 /*
4000                  * chunk-size has to be a power of 2
4001                  */
4002                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
4003                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
4004                         return -EINVAL;
4005                 }
4006
4007                 /* devices must have minimum size of one chunk */
4008                 list_for_each_entry(rdev, &mddev->disks, same_set) {
4009                         if (test_bit(Faulty, &rdev->flags))
4010                                 continue;
4011                         if (rdev->sectors < chunk_size / 512) {
4012                                 printk(KERN_WARNING
4013                                         "md: Dev %s smaller than chunk_size:"
4014                                         " %llu < %d\n",
4015                                         bdevname(rdev->bdev,b),
4016                                         (unsigned long long)rdev->sectors,
4017                                         chunk_size / 512);
4018                                 return -EINVAL;
4019                         }
4020                 }
4021         }
4022
4023         if (mddev->level != LEVEL_NONE)
4024                 request_module("md-level-%d", mddev->level);
4025         else if (mddev->clevel[0])
4026                 request_module("md-%s", mddev->clevel);
4027
4028         /*
4029          * Drop all container device buffers, from now on
4030          * the only valid external interface is through the md
4031          * device.
4032          */
4033         list_for_each_entry(rdev, &mddev->disks, same_set) {
4034                 if (test_bit(Faulty, &rdev->flags))
4035                         continue;
4036                 sync_blockdev(rdev->bdev);
4037                 invalidate_bdev(rdev->bdev);
4038
4039                 /* perform some consistency tests on the device.
4040                  * We don't want the data to overlap the metadata,
4041                  * Internal Bitmap issues have been handled elsewhere.
4042                  */
4043                 if (rdev->data_offset < rdev->sb_start) {
4044                         if (mddev->dev_sectors &&
4045                             rdev->data_offset + mddev->dev_sectors
4046                             > rdev->sb_start) {
4047                                 printk("md: %s: data overlaps metadata\n",
4048                                        mdname(mddev));
4049                                 return -EINVAL;
4050                         }
4051                 } else {
4052                         if (rdev->sb_start + rdev->sb_size/512
4053                             > rdev->data_offset) {
4054                                 printk("md: %s: metadata overlaps data\n",
4055                                        mdname(mddev));
4056                                 return -EINVAL;
4057                         }
4058                 }
4059                 sysfs_notify_dirent(rdev->sysfs_state);
4060         }
4061
4062         md_probe(mddev->unit, NULL, NULL);
4063         disk = mddev->gendisk;
4064         if (!disk)
4065                 return -ENOMEM;
4066
4067         spin_lock(&pers_lock);
4068         pers = find_pers(mddev->level, mddev->clevel);
4069         if (!pers || !try_module_get(pers->owner)) {
4070                 spin_unlock(&pers_lock);
4071                 if (mddev->level != LEVEL_NONE)
4072                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
4073                                mddev->level);
4074                 else
4075                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
4076                                mddev->clevel);
4077                 return -EINVAL;
4078         }
4079         mddev->pers = pers;
4080         spin_unlock(&pers_lock);
4081         if (mddev->level != pers->level) {
4082                 mddev->level = pers->level;
4083                 mddev->new_level = pers->level;
4084         }
4085         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
4086
4087         if (pers->level >= 4 && pers->level <= 6)
4088                 /* Cannot support integrity (yet) */
4089                 blk_integrity_unregister(mddev->gendisk);
4090
4091         if (mddev->reshape_position != MaxSector &&
4092             pers->start_reshape == NULL) {
4093                 /* This personality cannot handle reshaping... */
4094                 mddev->pers = NULL;
4095                 module_put(pers->owner);
4096                 return -EINVAL;
4097         }
4098
4099         if (pers->sync_request) {
4100                 /* Warn if this is a potentially silly
4101                  * configuration.
4102                  */
4103                 char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4104                 mdk_rdev_t *rdev2;
4105                 int warned = 0;
4106
4107                 list_for_each_entry(rdev, &mddev->disks, same_set)
4108                         list_for_each_entry(rdev2, &mddev->disks, same_set) {
4109                                 if (rdev < rdev2 &&
4110                                     rdev->bdev->bd_contains ==
4111                                     rdev2->bdev->bd_contains) {
4112                                         printk(KERN_WARNING
4113                                                "%s: WARNING: %s appears to be"
4114                                                " on the same physical disk as"
4115                                                " %s.\n",
4116                                                mdname(mddev),
4117                                                bdevname(rdev->bdev,b),
4118                                                bdevname(rdev2->bdev,b2));
4119                                         warned = 1;
4120                                 }
4121                         }
4122
4123                 if (warned)
4124                         printk(KERN_WARNING
4125                                "True protection against single-disk"
4126                                " failure might be compromised.\n");
4127         }
4128
4129         mddev->recovery = 0;
4130         /* may be over-ridden by personality */
4131         mddev->resync_max_sectors = mddev->dev_sectors;
4132
4133         mddev->barriers_work = 1;
4134         mddev->ok_start_degraded = start_dirty_degraded;
4135
4136         if (start_readonly)
4137                 mddev->ro = 2; /* read-only, but switch on first write */
4138
4139         err = mddev->pers->run(mddev);
4140         if (err)
4141                 printk(KERN_ERR "md: pers->run() failed ...\n");
4142         else if (mddev->pers->size(mddev, 0, 0) < mddev->array_sectors) {
4143                 WARN_ONCE(!mddev->external_size, "%s: default size too small,"
4144                           " but 'external_size' not in effect?\n", __func__);
4145                 printk(KERN_ERR
4146                        "md: invalid array_size %llu > default size %llu\n",
4147                        (unsigned long long)mddev->array_sectors / 2,
4148                        (unsigned long long)mddev->pers->size(mddev, 0, 0) / 2);
4149                 err = -EINVAL;
4150                 mddev->pers->stop(mddev);
4151         }
4152         if (err == 0 && mddev->pers->sync_request) {
4153                 err = bitmap_create(mddev);
4154                 if (err) {
4155                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
4156                                mdname(mddev), err);
4157                         mddev->pers->stop(mddev);
4158                 }
4159         }
4160         if (err) {
4161                 module_put(mddev->pers->owner);
4162                 mddev->pers = NULL;
4163                 bitmap_destroy(mddev);
4164                 return err;
4165         }
4166         if (mddev->pers->sync_request) {
4167                 if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
4168                         printk(KERN_WARNING
4169                                "md: cannot register extra attributes for %s\n",
4170                                mdname(mddev));
4171                 mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action");
4172         } else if (mddev->ro == 2) /* auto-readonly not meaningful */
4173                 mddev->ro = 0;
4174
4175         atomic_set(&mddev->writes_pending,0);
4176         mddev->safemode = 0;
4177         mddev->safemode_timer.function = md_safemode_timeout;
4178         mddev->safemode_timer.data = (unsigned long) mddev;
4179         mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
4180         mddev->in_sync = 1;
4181
4182         list_for_each_entry(rdev, &mddev->disks, same_set)
4183                 if (rdev->raid_disk >= 0) {
4184                         char nm[20];
4185                         sprintf(nm, "rd%d", rdev->raid_disk);
4186                         if (sysfs_create_link(&mddev->kobj, &rdev->kobj, nm))
4187                                 printk("md: cannot register %s for %s\n",
4188                                        nm, mdname(mddev));
4189                 }
4190         
4191         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4192         
4193         if (mddev->flags)
4194                 md_update_sb(mddev, 0);
4195
4196         set_capacity(disk, mddev->array_sectors);
4197
4198         /* If there is a partially-recovered drive we need to
4199          * start recovery here.  If we leave it to md_check_recovery,
4200          * it will remove the drives and not do the right thing
4201          */
4202         if (mddev->degraded && !mddev->sync_thread) {
4203                 int spares = 0;
4204                 list_for_each_entry(rdev, &mddev->disks, same_set)
4205                         if (rdev->raid_disk >= 0 &&
4206                             !test_bit(In_sync, &rdev->flags) &&
4207                             !test_bit(Faulty, &rdev->flags))
4208                                 /* complete an interrupted recovery */
4209                                 spares++;
4210                 if (spares && mddev->pers->sync_request) {
4211                         mddev->recovery = 0;
4212                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
4213                         mddev->sync_thread = md_register_thread(md_do_sync,
4214                                                                 mddev,
4215                                                                 "%s_resync");
4216                         if (!mddev->sync_thread) {
4217                                 printk(KERN_ERR "%s: could not start resync"
4218                                        " thread...\n",
4219                                        mdname(mddev));
4220                                 /* leave the spares where they are, it shouldn't hurt */
4221                                 mddev->recovery = 0;
4222                         }
4223                 }
4224         }
4225         md_wakeup_thread(mddev->thread);
4226         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
4227
4228         mddev->changed = 1;
4229         md_new_event(mddev);
4230         sysfs_notify_dirent(mddev->sysfs_state);
4231         if (mddev->sysfs_action)
4232                 sysfs_notify_dirent(mddev->sysfs_action);
4233         sysfs_notify(&mddev->kobj, NULL, "degraded");
4234         kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
4235         return 0;
4236 }
4237
4238 static int restart_array(mddev_t *mddev)
4239 {
4240         struct gendisk *disk = mddev->gendisk;
4241
4242         /* Complain if it has no devices */
4243         if (list_empty(&mddev->disks))
4244                 return -ENXIO;
4245         if (!mddev->pers)
4246                 return -EINVAL;
4247         if (!mddev->ro)
4248                 return -EBUSY;
4249         mddev->safemode = 0;
4250         mddev->ro = 0;
4251         set_disk_ro(disk, 0);
4252         printk(KERN_INFO "md: %s switched to read-write mode.\n",
4253                 mdname(mddev));
4254         /* Kick recovery or resync if necessary */
4255         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4256         md_wakeup_thread(mddev->thread);
4257         md_wakeup_thread(mddev->sync_thread);
4258         sysfs_notify_dirent(mddev->sysfs_state);
4259         return 0;
4260 }
4261
4262 /* similar to deny_write_access, but accounts for our holding a reference
4263  * to the file ourselves */
4264 static int deny_bitmap_write_access(struct file * file)
4265 {
4266         struct inode *inode = file->f_mapping->host;
4267
4268         spin_lock(&inode->i_lock);
4269         if (atomic_read(&inode->i_writecount) > 1) {
4270                 spin_unlock(&inode->i_lock);
4271                 return -ETXTBSY;
4272         }
4273         atomic_set(&inode->i_writecount, -1);
4274         spin_unlock(&inode->i_lock);
4275
4276         return 0;
4277 }
4278
4279 static void restore_bitmap_write_access(struct file *file)
4280 {
4281         struct inode *inode = file->f_mapping->host;
4282
4283         spin_lock(&inode->i_lock);
4284         atomic_set(&inode->i_writecount, 1);
4285         spin_unlock(&inode->i_lock);
4286 }
4287
4288 /* mode:
4289  *   0 - completely stop and dis-assemble array
4290  *   1 - switch to readonly
4291  *   2 - stop but do not disassemble array
4292  */
4293 static int do_md_stop(mddev_t * mddev, int mode, int is_open)
4294 {
4295         int err = 0;
4296         struct gendisk *disk = mddev->gendisk;
4297         mdk_rdev_t *rdev;
4298
4299         if (atomic_read(&mddev->openers) > is_open) {
4300                 printk("md: %s still in use.\n",mdname(mddev));
4301                 return -EBUSY;
4302         }
4303
4304         if (mddev->pers) {
4305
4306                 if (mddev->sync_thread) {
4307                         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4308                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4309                         md_unregister_thread(mddev->sync_thread);
4310                         mddev->sync_thread = NULL;
4311                 }
4312
4313                 del_timer_sync(&mddev->safemode_timer);
4314
4315                 switch(mode) {
4316                 case 1: /* readonly */
4317                         err  = -ENXIO;
4318                         if (mddev->ro==1)
4319                                 goto out;
4320                         mddev->ro = 1;
4321                         break;
4322                 case 0: /* disassemble */
4323                 case 2: /* stop */
4324                         bitmap_flush(mddev);
4325                         md_super_wait(mddev);
4326                         if (mddev->ro)
4327                                 set_disk_ro(disk, 0);
4328
4329                         mddev->pers->stop(mddev);
4330                         mddev->queue->merge_bvec_fn = NULL;
4331                         mddev->queue->unplug_fn = NULL;
4332                         mddev->queue->backing_dev_info.congested_fn = NULL;
4333                         module_put(mddev->pers->owner);
4334                         if (mddev->pers->sync_request)
4335                                 mddev->private = &md_redundancy_group;
4336                         mddev->pers = NULL;
4337                         /* tell userspace to handle 'inactive' */
4338                         sysfs_notify_dirent(mddev->sysfs_state);
4339
4340                         list_for_each_entry(rdev, &mddev->disks, same_set)
4341                                 if (rdev->raid_disk >= 0) {
4342                                         char nm[20];
4343                                         sprintf(nm, "rd%d", rdev->raid_disk);
4344                                         sysfs_remove_link(&mddev->kobj, nm);
4345                                 }
4346
4347                         set_capacity(disk, 0);
4348                         mddev->changed = 1;
4349
4350                         if (mddev->ro)
4351                                 mddev->ro = 0;
4352                 }
4353                 if (!mddev->in_sync || mddev->flags) {
4354                         /* mark array as shutdown cleanly */
4355                         mddev->in_sync = 1;
4356                         md_update_sb(mddev, 1);
4357                 }
4358                 if (mode == 1)
4359                         set_disk_ro(disk, 1);
4360                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4361         }
4362
4363         /*
4364          * Free resources if final stop
4365          */
4366         if (mode == 0) {
4367
4368                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
4369
4370                 bitmap_destroy(mddev);
4371                 if (mddev->bitmap_file) {
4372                         restore_bitmap_write_access(mddev->bitmap_file);
4373                         fput(mddev->bitmap_file);
4374                         mddev->bitmap_file = NULL;
4375                 }
4376                 mddev->bitmap_offset = 0;
4377
4378                 /* make sure all md_delayed_delete calls have finished */
4379                 flush_scheduled_work();
4380
4381                 export_array(mddev);
4382
4383                 mddev->array_sectors = 0;
4384                 mddev->external_size = 0;
4385                 mddev->dev_sectors = 0;
4386                 mddev->raid_disks = 0;
4387                 mddev->recovery_cp = 0;
4388                 mddev->resync_min = 0;
4389                 mddev->resync_max = MaxSector;
4390                 mddev->reshape_position = MaxSector;
4391                 mddev->external = 0;
4392                 mddev->persistent = 0;
4393                 mddev->level = LEVEL_NONE;
4394                 mddev->clevel[0] = 0;
4395                 mddev->flags = 0;
4396                 mddev->ro = 0;
4397                 mddev->metadata_type[0] = 0;
4398                 mddev->chunk_size = 0;
4399                 mddev->ctime = mddev->utime = 0;
4400                 mddev->layout = 0;
4401                 mddev->max_disks = 0;
4402                 mddev->events = 0;
4403                 mddev->delta_disks = 0;
4404                 mddev->new_level = LEVEL_NONE;
4405                 mddev->new_layout = 0;
4406                 mddev->new_chunk = 0;
4407                 mddev->curr_resync = 0;
4408                 mddev->resync_mismatches = 0;
4409                 mddev->suspend_lo = mddev->suspend_hi = 0;
4410                 mddev->sync_speed_min = mddev->sync_speed_max = 0;
4411                 mddev->recovery = 0;
4412                 mddev->in_sync = 0;
4413                 mddev->changed = 0;
4414                 mddev->degraded = 0;
4415                 mddev->barriers_work = 0;
4416                 mddev->safemode = 0;
4417                 kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
4418                 if (mddev->hold_active == UNTIL_STOP)
4419                         mddev->hold_active = 0;
4420
4421         } else if (mddev->pers)
4422                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
4423                         mdname(mddev));
4424         err = 0;
4425         blk_integrity_unregister(disk);
4426         md_new_event(mddev);
4427         sysfs_notify_dirent(mddev->sysfs_state);
4428 out:
4429         return err;
4430 }
4431
4432 #ifndef MODULE
4433 static void autorun_array(mddev_t *mddev)
4434 {
4435         mdk_rdev_t *rdev;
4436         int err;
4437
4438         if (list_empty(&mddev->disks))
4439                 return;
4440
4441         printk(KERN_INFO "md: running: ");
4442
4443         list_for_each_entry(rdev, &mddev->disks, same_set) {
4444                 char b[BDEVNAME_SIZE];
4445                 printk("<%s>", bdevname(rdev->bdev,b));
4446         }
4447         printk("\n");
4448
4449         err = do_md_run(mddev);
4450         if (err) {
4451                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
4452                 do_md_stop(mddev, 0, 0);
4453         }
4454 }
4455
4456 /*
4457  * lets try to run arrays based on all disks that have arrived
4458  * until now. (those are in pending_raid_disks)
4459  *
4460  * the method: pick the first pending disk, collect all disks with
4461  * the same UUID, remove all from the pending list and put them into
4462  * the 'same_array' list. Then order this list based on superblock
4463  * update time (freshest comes first), kick out 'old' disks and
4464  * compare superblocks. If everything's fine then run it.
4465  *
4466  * If "unit" is allocated, then bump its reference count
4467  */
4468 static void autorun_devices(int part)
4469 {
4470         mdk_rdev_t *rdev0, *rdev, *tmp;
4471         mddev_t *mddev;
4472         char b[BDEVNAME_SIZE];
4473
4474         printk(KERN_INFO "md: autorun ...\n");
4475         while (!list_empty(&pending_raid_disks)) {
4476                 int unit;
4477                 dev_t dev;
4478                 LIST_HEAD(candidates);
4479                 rdev0 = list_entry(pending_raid_disks.next,
4480                                          mdk_rdev_t, same_set);
4481
4482                 printk(KERN_INFO "md: considering %s ...\n",
4483                         bdevname(rdev0->bdev,b));
4484                 INIT_LIST_HEAD(&candidates);
4485                 rdev_for_each_list(rdev, tmp, &pending_raid_disks)
4486                         if (super_90_load(rdev, rdev0, 0) >= 0) {
4487                                 printk(KERN_INFO "md:  adding %s ...\n",
4488                                         bdevname(rdev->bdev,b));
4489                                 list_move(&rdev->same_set, &candidates);
4490                         }
4491                 /*
4492                  * now we have a set of devices, with all of them having
4493                  * mostly sane superblocks. It's time to allocate the
4494                  * mddev.
4495                  */
4496                 if (part) {
4497                         dev = MKDEV(mdp_major,
4498                                     rdev0->preferred_minor << MdpMinorShift);
4499                         unit = MINOR(dev) >> MdpMinorShift;
4500                 } else {
4501                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
4502                         unit = MINOR(dev);
4503                 }
4504                 if (rdev0->preferred_minor != unit) {
4505                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
4506                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
4507                         break;
4508                 }
4509
4510                 md_probe(dev, NULL, NULL);
4511                 mddev = mddev_find(dev);
4512                 if (!mddev || !mddev->gendisk) {
4513                         if (mddev)
4514                                 mddev_put(mddev);
4515                         printk(KERN_ERR
4516                                 "md: cannot allocate memory for md drive.\n");
4517                         break;
4518                 }
4519                 if (mddev_lock(mddev)) 
4520                         printk(KERN_WARNING "md: %s locked, cannot run\n",
4521                                mdname(mddev));
4522                 else if (mddev->raid_disks || mddev->major_version
4523                          || !list_empty(&mddev->disks)) {
4524                         printk(KERN_WARNING 
4525                                 "md: %s already running, cannot run %s\n",
4526                                 mdname(mddev), bdevname(rdev0->bdev,b));
4527                         mddev_unlock(mddev);
4528                 } else {
4529                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
4530                         mddev->persistent = 1;
4531                         rdev_for_each_list(rdev, tmp, &candidates) {
4532                                 list_del_init(&rdev->same_set);
4533                                 if (bind_rdev_to_array(rdev, mddev))
4534                                         export_rdev(rdev);
4535                         }
4536                         autorun_array(mddev);
4537                         mddev_unlock(mddev);
4538                 }
4539                 /* on success, candidates will be empty, on error
4540                  * it won't...
4541                  */
4542                 rdev_for_each_list(rdev, tmp, &candidates) {
4543                         list_del_init(&rdev->same_set);
4544                         export_rdev(rdev);
4545                 }
4546                 mddev_put(mddev);
4547         }
4548         printk(KERN_INFO "md: ... autorun DONE.\n");
4549 }
4550 #endif /* !MODULE */
4551
4552 static int get_version(void __user * arg)
4553 {
4554         mdu_version_t ver;
4555
4556         ver.major = MD_MAJOR_VERSION;
4557         ver.minor = MD_MINOR_VERSION;
4558         ver.patchlevel = MD_PATCHLEVEL_VERSION;
4559
4560         if (copy_to_user(arg, &ver, sizeof(ver)))
4561                 return -EFAULT;
4562
4563         return 0;
4564 }
4565
4566 static int get_array_info(mddev_t * mddev, void __user * arg)
4567 {
4568         mdu_array_info_t info;
4569         int nr,working,active,failed,spare;
4570         mdk_rdev_t *rdev;
4571
4572         nr=working=active=failed=spare=0;
4573         list_for_each_entry(rdev, &mddev->disks, same_set) {
4574                 nr++;
4575                 if (test_bit(Faulty, &rdev->flags))
4576                         failed++;
4577                 else {
4578                         working++;
4579                         if (test_bit(In_sync, &rdev->flags))
4580                                 active++;       
4581                         else
4582                                 spare++;
4583                 }
4584         }
4585
4586         info.major_version = mddev->major_version;
4587         info.minor_version = mddev->minor_version;
4588         info.patch_version = MD_PATCHLEVEL_VERSION;
4589         info.ctime         = mddev->ctime;
4590         info.level         = mddev->level;
4591         info.size          = mddev->dev_sectors / 2;
4592         if (info.size != mddev->dev_sectors / 2) /* overflow */
4593                 info.size = -1;
4594         info.nr_disks      = nr;
4595         info.raid_disks    = mddev->raid_disks;
4596         info.md_minor      = mddev->md_minor;
4597         info.not_persistent= !mddev->persistent;
4598
4599         info.utime         = mddev->utime;
4600         info.state         = 0;
4601         if (mddev->in_sync)
4602                 info.state = (1<<MD_SB_CLEAN);
4603         if (mddev->bitmap && mddev->bitmap_offset)
4604                 info.state = (1<<MD_SB_BITMAP_PRESENT);
4605         info.active_disks  = active;
4606         info.working_disks = working;
4607         info.failed_disks  = failed;
4608         info.spare_disks   = spare;
4609
4610         info.layout        = mddev->layout;
4611         info.chunk_size    = mddev->chunk_size;
4612
4613         if (copy_to_user(arg, &info, sizeof(info)))
4614                 return -EFAULT;
4615
4616         return 0;
4617 }
4618
4619 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
4620 {
4621         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
4622         char *ptr, *buf = NULL;
4623         int err = -ENOMEM;
4624
4625         if (md_allow_write(mddev))
4626                 file = kmalloc(sizeof(*file), GFP_NOIO);
4627         else
4628                 file = kmalloc(sizeof(*file), GFP_KERNEL);
4629
4630         if (!file)
4631                 goto out;
4632
4633         /* bitmap disabled, zero the first byte and copy out */
4634         if (!mddev->bitmap || !mddev->bitmap->file) {
4635                 file->pathname[0] = '\0';
4636                 goto copy_out;
4637         }
4638
4639         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
4640         if (!buf)
4641                 goto out;
4642
4643         ptr = d_path(&mddev->bitmap->file->f_path, buf, sizeof(file->pathname));
4644         if (IS_ERR(ptr))
4645                 goto out;
4646
4647         strcpy(file->pathname, ptr);
4648
4649 copy_out:
4650         err = 0;
4651         if (copy_to_user(arg, file, sizeof(*file)))
4652                 err = -EFAULT;
4653 out:
4654         kfree(buf);
4655         kfree(file);
4656         return err;
4657 }
4658
4659 static int get_disk_info(mddev_t * mddev, void __user * arg)
4660 {
4661         mdu_disk_info_t info;
4662         mdk_rdev_t *rdev;
4663
4664         if (copy_from_user(&info, arg, sizeof(info)))
4665                 return -EFAULT;
4666
4667         rdev = find_rdev_nr(mddev, info.number);
4668         if (rdev) {
4669                 info.major = MAJOR(rdev->bdev->bd_dev);
4670                 info.minor = MINOR(rdev->bdev->bd_dev);
4671                 info.raid_disk = rdev->raid_disk;
4672                 info.state = 0;
4673                 if (test_bit(Faulty, &rdev->flags))
4674                         info.state |= (1<<MD_DISK_FAULTY);
4675                 else if (test_bit(In_sync, &rdev->flags)) {
4676                         info.state |= (1<<MD_DISK_ACTIVE);
4677                         info.state |= (1<<MD_DISK_SYNC);
4678                 }
4679                 if (test_bit(WriteMostly, &rdev->flags))
4680                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
4681         } else {
4682                 info.major = info.minor = 0;
4683                 info.raid_disk = -1;
4684                 info.state = (1<<MD_DISK_REMOVED);
4685         }
4686
4687         if (copy_to_user(arg, &info, sizeof(info)))
4688                 return -EFAULT;
4689
4690         return 0;
4691 }
4692
4693 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
4694 {
4695         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4696         mdk_rdev_t *rdev;
4697         dev_t dev = MKDEV(info->major,info->minor);
4698
4699         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
4700                 return -EOVERFLOW;
4701
4702         if (!mddev->raid_disks) {
4703                 int err;
4704                 /* expecting a device which has a superblock */
4705                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
4706                 if (IS_ERR(rdev)) {
4707                         printk(KERN_WARNING 
4708                                 "md: md_import_device returned %ld\n",
4709                                 PTR_ERR(rdev));
4710                         return PTR_ERR(rdev);
4711                 }
4712                 if (!list_empty(&mddev->disks)) {
4713                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
4714                                                         mdk_rdev_t, same_set);
4715                         int err = super_types[mddev->major_version]
4716                                 .load_super(rdev, rdev0, mddev->minor_version);
4717                         if (err < 0) {
4718                                 printk(KERN_WARNING 
4719                                         "md: %s has different UUID to %s\n",
4720                                         bdevname(rdev->bdev,b), 
4721                                         bdevname(rdev0->bdev,b2));
4722                                 export_rdev(rdev);
4723                                 return -EINVAL;
4724                         }
4725                 }
4726                 err = bind_rdev_to_array(rdev, mddev);
4727                 if (err)
4728                         export_rdev(rdev);
4729                 return err;
4730         }
4731
4732         /*
4733          * add_new_disk can be used once the array is assembled
4734          * to add "hot spares".  They must already have a superblock
4735          * written
4736          */
4737         if (mddev->pers) {
4738                 int err;
4739                 if (!mddev->pers->hot_add_disk) {
4740                         printk(KERN_WARNING 
4741                                 "%s: personality does not support diskops!\n",
4742                                mdname(mddev));
4743                         return -EINVAL;
4744                 }
4745                 if (mddev->persistent)
4746                         rdev = md_import_device(dev, mddev->major_version,
4747                                                 mddev->minor_version);
4748                 else
4749                         rdev = md_import_device(dev, -1, -1);
4750                 if (IS_ERR(rdev)) {
4751                         printk(KERN_WARNING 
4752                                 "md: md_import_device returned %ld\n",
4753                                 PTR_ERR(rdev));
4754                         return PTR_ERR(rdev);
4755                 }
4756                 /* set save_raid_disk if appropriate */
4757                 if (!mddev->persistent) {
4758                         if (info->state & (1<<MD_DISK_SYNC)  &&
4759                             info->raid_disk < mddev->raid_disks)
4760                                 rdev->raid_disk = info->raid_disk;
4761                         else
4762                                 rdev->raid_disk = -1;
4763                 } else
4764                         super_types[mddev->major_version].
4765                                 validate_super(mddev, rdev);
4766                 rdev->saved_raid_disk = rdev->raid_disk;
4767
4768                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
4769                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4770                         set_bit(WriteMostly, &rdev->flags);
4771                 else
4772                         clear_bit(WriteMostly, &rdev->flags);
4773
4774                 rdev->raid_disk = -1;
4775                 err = bind_rdev_to_array(rdev, mddev);
4776                 if (!err && !mddev->pers->hot_remove_disk) {
4777                         /* If there is hot_add_disk but no hot_remove_disk
4778                          * then added disks for geometry changes,
4779                          * and should be added immediately.
4780                          */
4781                         super_types[mddev->major_version].
4782                                 validate_super(mddev, rdev);
4783                         err = mddev->pers->hot_add_disk(mddev, rdev);
4784                         if (err)
4785                                 unbind_rdev_from_array(rdev);
4786                 }
4787                 if (err)
4788                         export_rdev(rdev);
4789                 else
4790                         sysfs_notify_dirent(rdev->sysfs_state);
4791
4792                 md_update_sb(mddev, 1);
4793                 if (mddev->degraded)
4794                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4795                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4796                 md_wakeup_thread(mddev->thread);
4797                 return err;
4798         }
4799
4800         /* otherwise, add_new_disk is only allowed
4801          * for major_version==0 superblocks
4802          */
4803         if (mddev->major_version != 0) {
4804                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
4805                        mdname(mddev));
4806                 return -EINVAL;
4807         }
4808
4809         if (!(info->state & (1<<MD_DISK_FAULTY))) {
4810                 int err;
4811                 rdev = md_import_device(dev, -1, 0);
4812                 if (IS_ERR(rdev)) {
4813                         printk(KERN_WARNING 
4814                                 "md: error, md_import_device() returned %ld\n",
4815                                 PTR_ERR(rdev));
4816                         return PTR_ERR(rdev);
4817                 }
4818                 rdev->desc_nr = info->number;
4819                 if (info->raid_disk < mddev->raid_disks)
4820                         rdev->raid_disk = info->raid_disk;
4821                 else
4822                         rdev->raid_disk = -1;
4823
4824                 if (rdev->raid_disk < mddev->raid_disks)
4825                         if (info->state & (1<<MD_DISK_SYNC))
4826                                 set_bit(In_sync, &rdev->flags);
4827
4828                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
4829                         set_bit(WriteMostly, &rdev->flags);
4830
4831                 if (!mddev->persistent) {
4832                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
4833                         rdev->sb_start = rdev->bdev->bd_inode->i_size / 512;
4834                 } else 
4835                         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
4836                 rdev->sectors = calc_num_sectors(rdev, mddev->chunk_size);
4837
4838                 err = bind_rdev_to_array(rdev, mddev);
4839                 if (err) {
4840                         export_rdev(rdev);
4841                         return err;
4842                 }
4843         }
4844
4845         return 0;
4846 }
4847
4848 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
4849 {
4850         char b[BDEVNAME_SIZE];
4851         mdk_rdev_t *rdev;
4852
4853         rdev = find_rdev(mddev, dev);
4854         if (!rdev)
4855                 return -ENXIO;
4856
4857         if (rdev->raid_disk >= 0)
4858                 goto busy;
4859
4860         kick_rdev_from_array(rdev);
4861         md_update_sb(mddev, 1);
4862         md_new_event(mddev);
4863
4864         return 0;
4865 busy:
4866         printk(KERN_WARNING "md: cannot remove active disk %s from %s ...\n",
4867                 bdevname(rdev->bdev,b), mdname(mddev));
4868         return -EBUSY;
4869 }
4870
4871 static int hot_add_disk(mddev_t * mddev, dev_t dev)
4872 {
4873         char b[BDEVNAME_SIZE];
4874         int err;
4875         mdk_rdev_t *rdev;
4876
4877         if (!mddev->pers)
4878                 return -ENODEV;
4879
4880         if (mddev->major_version != 0) {
4881                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
4882                         " version-0 superblocks.\n",
4883                         mdname(mddev));
4884                 return -EINVAL;
4885         }
4886         if (!mddev->pers->hot_add_disk) {
4887                 printk(KERN_WARNING 
4888                         "%s: personality does not support diskops!\n",
4889                         mdname(mddev));
4890                 return -EINVAL;
4891         }
4892
4893         rdev = md_import_device(dev, -1, 0);
4894         if (IS_ERR(rdev)) {
4895                 printk(KERN_WARNING 
4896                         "md: error, md_import_device() returned %ld\n",
4897                         PTR_ERR(rdev));
4898                 return -EINVAL;
4899         }
4900
4901         if (mddev->persistent)
4902                 rdev->sb_start = calc_dev_sboffset(rdev->bdev);
4903         else
4904                 rdev->sb_start = rdev->bdev->bd_inode->i_size / 512;
4905
4906         rdev->sectors = calc_num_sectors(rdev, mddev->chunk_size);
4907
4908         if (test_bit(Faulty, &rdev->flags)) {
4909                 printk(KERN_WARNING 
4910                         "md: can not hot-add faulty %s disk to %s!\n",
4911                         bdevname(rdev->bdev,b), mdname(mddev));
4912                 err = -EINVAL;
4913                 goto abort_export;
4914         }
4915         clear_bit(In_sync, &rdev->flags);
4916         rdev->desc_nr = -1;
4917         rdev->saved_raid_disk = -1;
4918         err = bind_rdev_to_array(rdev, mddev);
4919         if (err)
4920                 goto abort_export;
4921
4922         /*
4923          * The rest should better be atomic, we can have disk failures
4924          * noticed in interrupt contexts ...
4925          */
4926
4927         rdev->raid_disk = -1;
4928
4929         md_update_sb(mddev, 1);
4930
4931         /*
4932          * Kick recovery, maybe this spare has to be added to the
4933          * array immediately.
4934          */
4935         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4936         md_wakeup_thread(mddev->thread);
4937         md_new_event(mddev);
4938         return 0;
4939
4940 abort_export:
4941         export_rdev(rdev);
4942         return err;
4943 }
4944
4945 static int set_bitmap_file(mddev_t *mddev, int fd)
4946 {
4947         int err;
4948
4949         if (mddev->pers) {
4950                 if (!mddev->pers->quiesce)
4951                         return -EBUSY;
4952                 if (mddev->recovery || mddev->sync_thread)
4953                         return -EBUSY;
4954                 /* we should be able to change the bitmap.. */
4955         }
4956
4957
4958         if (fd >= 0) {
4959                 if (mddev->bitmap)
4960                         return -EEXIST; /* cannot add when bitmap is present */
4961                 mddev->bitmap_file = fget(fd);
4962
4963                 if (mddev->bitmap_file == NULL) {
4964                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
4965                                mdname(mddev));
4966                         return -EBADF;
4967                 }
4968
4969                 err = deny_bitmap_write_access(mddev->bitmap_file);
4970                 if (err) {
4971                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
4972                                mdname(mddev));
4973                         fput(mddev->bitmap_file);
4974                         mddev->bitmap_file = NULL;
4975                         return err;
4976                 }
4977                 mddev->bitmap_offset = 0; /* file overrides offset */
4978         } else if (mddev->bitmap == NULL)
4979                 return -ENOENT; /* cannot remove what isn't there */
4980         err = 0;
4981         if (mddev->pers) {
4982                 mddev->pers->quiesce(mddev, 1);
4983                 if (fd >= 0)
4984                         err = bitmap_create(mddev);
4985                 if (fd < 0 || err) {
4986                         bitmap_destroy(mddev);
4987                         fd = -1; /* make sure to put the file */
4988                 }
4989                 mddev->pers->quiesce(mddev, 0);
4990         }
4991         if (fd < 0) {
4992                 if (mddev->bitmap_file) {
4993                         restore_bitmap_write_access(mddev->bitmap_file);
4994                         fput(mddev->bitmap_file);
4995                 }
4996                 mddev->bitmap_file = NULL;
4997         }
4998
4999         return err;
5000 }
5001
5002 /*
5003  * set_array_info is used two different ways
5004  * The original usage is when creating a new array.
5005  * In this usage, raid_disks is > 0 and it together with
5006  *  level, size, not_persistent,layout,chunksize determine the
5007  *  shape of the array.
5008  *  This will always create an array with a type-0.90.0 superblock.
5009  * The newer usage is when assembling an array.
5010  *  In this case raid_disks will be 0, and the major_version field is
5011  *  use to determine which style super-blocks are to be found on the devices.
5012  *  The minor and patch _version numbers are also kept incase the
5013  *  super_block handler wishes to interpret them.
5014  */
5015 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
5016 {
5017
5018         if (info->raid_disks == 0) {
5019                 /* just setting version number for superblock loading */
5020                 if (info->major_version < 0 ||
5021                     info->major_version >= ARRAY_SIZE(super_types) ||
5022                     super_types[info->major_version].name == NULL) {
5023                         /* maybe try to auto-load a module? */
5024                         printk(KERN_INFO 
5025                                 "md: superblock version %d not known\n",
5026                                 info->major_version);
5027                         return -EINVAL;
5028                 }
5029                 mddev->major_version = info->major_version;
5030                 mddev->minor_version = info->minor_version;
5031                 mddev->patch_version = info->patch_version;
5032                 mddev->persistent = !info->not_persistent;
5033                 return 0;
5034         }
5035         mddev->major_version = MD_MAJOR_VERSION;
5036         mddev->minor_version = MD_MINOR_VERSION;
5037         mddev->patch_version = MD_PATCHLEVEL_VERSION;
5038         mddev->ctime         = get_seconds();
5039
5040         mddev->level         = info->level;
5041         mddev->clevel[0]     = 0;
5042         mddev->dev_sectors   = 2 * (sector_t)info->size;
5043         mddev->raid_disks    = info->raid_disks;
5044         /* don't set md_minor, it is determined by which /dev/md* was
5045          * openned
5046          */
5047         if (info->state & (1<<MD_SB_CLEAN))
5048                 mddev->recovery_cp = MaxSector;
5049         else
5050                 mddev->recovery_cp = 0;
5051         mddev->persistent    = ! info->not_persistent;
5052         mddev->external      = 0;
5053
5054         mddev->layout        = info->layout;
5055         mddev->chunk_size    = info->chunk_size;
5056
5057         mddev->max_disks     = MD_SB_DISKS;
5058
5059         if (mddev->persistent)
5060                 mddev->flags         = 0;
5061         set_bit(MD_CHANGE_DEVS, &mddev->flags);
5062
5063         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
5064         mddev->bitmap_offset = 0;
5065
5066         mddev->reshape_position = MaxSector;
5067
5068         /*
5069          * Generate a 128 bit UUID
5070          */
5071         get_random_bytes(mddev->uuid, 16);
5072
5073         mddev->new_level = mddev->level;
5074         mddev->new_chunk = mddev->chunk_size;
5075         mddev->new_layout = mddev->layout;
5076         mddev->delta_disks = 0;
5077
5078         return 0;
5079 }
5080
5081 void md_set_array_sectors(mddev_t *mddev, sector_t array_sectors)
5082 {
5083         WARN(!mddev_is_locked(mddev), "%s: unlocked mddev!\n", __func__);
5084
5085         if (mddev->external_size)
5086                 return;
5087
5088         mddev->array_sectors = array_sectors;
5089 }
5090 EXPORT_SYMBOL(md_set_array_sectors);
5091
5092 static int update_size(mddev_t *mddev, sector_t num_sectors)
5093 {
5094         mdk_rdev_t *rdev;
5095         int rv;
5096         int fit = (num_sectors == 0);
5097
5098         if (mddev->pers->resize == NULL)
5099                 return -EINVAL;
5100         /* The "num_sectors" is the number of sectors of each device that
5101          * is used.  This can only make sense for arrays with redundancy.
5102          * linear and raid0 always use whatever space is available. We can only
5103          * consider changing this number if no resync or reconstruction is
5104          * happening, and if the new size is acceptable. It must fit before the
5105          * sb_start or, if that is <data_offset, it must fit before the size
5106          * of each device.  If num_sectors is zero, we find the largest size
5107          * that fits.
5108
5109          */
5110         if (mddev->sync_thread)
5111                 return -EBUSY;
5112         if (mddev->bitmap)
5113                 /* Sorry, cannot grow a bitmap yet, just remove it,
5114                  * grow, and re-add.
5115                  */
5116                 return -EBUSY;
5117         list_for_each_entry(rdev, &mddev->disks, same_set) {
5118                 sector_t avail = rdev->sectors;
5119
5120                 if (fit && (num_sectors == 0 || num_sectors > avail))
5121                         num_sectors = avail;
5122                 if (avail < num_sectors)
5123                         return -ENOSPC;
5124         }
5125         rv = mddev->pers->resize(mddev, num_sectors);
5126         if (!rv) {
5127                 struct block_device *bdev;
5128
5129                 bdev = bdget_disk(mddev->gendisk, 0);
5130                 if (bdev) {
5131                         mutex_lock(&bdev->bd_inode->i_mutex);
5132                         i_size_write(bdev->bd_inode,
5133                                      (loff_t)mddev->array_sectors << 9);
5134                         mutex_unlock(&bdev->bd_inode->i_mutex);
5135                         bdput(bdev);
5136                 }
5137         }
5138         return rv;
5139 }
5140
5141 static int update_raid_disks(mddev_t *mddev, int raid_disks)
5142 {
5143         int rv;
5144         /* change the number of raid disks */
5145         if (mddev->pers->check_reshape == NULL)
5146                 return -EINVAL;
5147         if (raid_disks <= 0 ||
5148             raid_disks >= mddev->max_disks)
5149                 return -EINVAL;
5150         if (mddev->sync_thread || mddev->reshape_position != MaxSector)
5151                 return -EBUSY;
5152         mddev->delta_disks = raid_disks - mddev->raid_disks;
5153
5154         rv = mddev->pers->check_reshape(mddev);
5155         return rv;
5156 }
5157
5158
5159 /*
5160  * update_array_info is used to change the configuration of an
5161  * on-line array.
5162  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
5163  * fields in the info are checked against the array.
5164  * Any differences that cannot be handled will cause an error.
5165  * Normally, only one change can be managed at a time.
5166  */
5167 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
5168 {
5169         int rv = 0;
5170         int cnt = 0;
5171         int state = 0;
5172
5173         /* calculate expected state,ignoring low bits */
5174         if (mddev->bitmap && mddev->bitmap_offset)
5175                 state |= (1 << MD_SB_BITMAP_PRESENT);
5176
5177         if (mddev->major_version != info->major_version ||
5178             mddev->minor_version != info->minor_version ||
5179 /*          mddev->patch_version != info->patch_version || */
5180             mddev->ctime         != info->ctime         ||
5181             mddev->level         != info->level         ||
5182 /*          mddev->layout        != info->layout        || */
5183             !mddev->persistent   != info->not_persistent||
5184             mddev->chunk_size    != info->chunk_size    ||
5185             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
5186             ((state^info->state) & 0xfffffe00)
5187                 )
5188                 return -EINVAL;
5189         /* Check there is only one change */
5190         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
5191                 cnt++;
5192         if (mddev->raid_disks != info->raid_disks)
5193                 cnt++;
5194         if (mddev->layout != info->layout)
5195                 cnt++;
5196         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT))
5197                 cnt++;
5198         if (cnt == 0)
5199                 return 0;
5200         if (cnt > 1)
5201                 return -EINVAL;
5202
5203         if (mddev->layout != info->layout) {
5204                 /* Change layout
5205                  * we don't need to do anything at the md level, the
5206                  * personality will take care of it all.
5207                  */
5208                 if (mddev->pers->reconfig == NULL)
5209                         return -EINVAL;
5210                 else
5211                         return mddev->pers->reconfig(mddev, info->layout, -1);
5212         }
5213         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
5214                 rv = update_size(mddev, (sector_t)info->size * 2);
5215
5216         if (mddev->raid_disks    != info->raid_disks)
5217                 rv = update_raid_disks(mddev, info->raid_disks);
5218
5219         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
5220                 if (mddev->pers->quiesce == NULL)
5221                         return -EINVAL;
5222                 if (mddev->recovery || mddev->sync_thread)
5223                         return -EBUSY;
5224                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
5225                         /* add the bitmap */
5226                         if (mddev->bitmap)
5227                                 return -EEXIST;
5228                         if (mddev->default_bitmap_offset == 0)
5229                                 return -EINVAL;
5230                         mddev->bitmap_offset = mddev->default_bitmap_offset;
5231                         mddev->pers->quiesce(mddev, 1);
5232                         rv = bitmap_create(mddev);
5233                         if (rv)
5234                                 bitmap_destroy(mddev);
5235                         mddev->pers->quiesce(mddev, 0);
5236                 } else {
5237                         /* remove the bitmap */
5238                         if (!mddev->bitmap)
5239                                 return -ENOENT;
5240                         if (mddev->bitmap->file)
5241                                 return -EINVAL;
5242                         mddev->pers->quiesce(mddev, 1);
5243                         bitmap_destroy(mddev);
5244                         mddev->pers->quiesce(mddev, 0);
5245                         mddev->bitmap_offset = 0;
5246                 }
5247         }
5248         md_update_sb(mddev, 1);
5249         return rv;
5250 }
5251
5252 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
5253 {
5254         mdk_rdev_t *rdev;
5255
5256         if (mddev->pers == NULL)
5257                 return -ENODEV;
5258
5259         rdev = find_rdev(mddev, dev);
5260         if (!rdev)
5261                 return -ENODEV;
5262
5263         md_error(mddev, rdev);
5264         return 0;
5265 }
5266
5267 /*
5268  * We have a problem here : there is no easy way to give a CHS
5269  * virtual geometry. We currently pretend that we have a 2 heads
5270  * 4 sectors (with a BIG number of cylinders...). This drives
5271  * dosfs just mad... ;-)
5272  */
5273 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
5274 {
5275         mddev_t *mddev = bdev->bd_disk->private_data;
5276
5277         geo->heads = 2;
5278         geo->sectors = 4;
5279         geo->cylinders = get_capacity(mddev->gendisk) / 8;
5280         return 0;
5281 }
5282
5283 static int md_ioctl(struct block_device *bdev, fmode_t mode,
5284                         unsigned int cmd, unsigned long arg)
5285 {
5286         int err = 0;
5287         void __user *argp = (void __user *)arg;
5288         mddev_t *mddev = NULL;
5289
5290         if (!capable(CAP_SYS_ADMIN))
5291                 return -EACCES;
5292
5293         /*
5294          * Commands dealing with the RAID driver but not any
5295          * particular array:
5296          */
5297         switch (cmd)
5298         {
5299                 case RAID_VERSION:
5300                         err = get_version(argp);
5301                         goto done;
5302
5303                 case PRINT_RAID_DEBUG:
5304                         err = 0;
5305                         md_print_devices();
5306                         goto done;
5307
5308 #ifndef MODULE
5309                 case RAID_AUTORUN:
5310                         err = 0;
5311                         autostart_arrays(arg);
5312                         goto done;
5313 #endif
5314                 default:;
5315         }
5316
5317         /*
5318          * Commands creating/starting a new array:
5319          */
5320
5321         mddev = bdev->bd_disk->private_data;
5322
5323         if (!mddev) {
5324                 BUG();
5325                 goto abort;
5326         }
5327
5328         err = mddev_lock(mddev);
5329         if (err) {
5330                 printk(KERN_INFO 
5331                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
5332                         err, cmd);
5333                 goto abort;
5334         }
5335
5336         switch (cmd)
5337         {
5338                 case SET_ARRAY_INFO:
5339                         {
5340                                 mdu_array_info_t info;
5341                                 if (!arg)
5342                                         memset(&info, 0, sizeof(info));
5343                                 else if (copy_from_user(&info, argp, sizeof(info))) {
5344                                         err = -EFAULT;
5345                                         goto abort_unlock;
5346                                 }
5347                                 if (mddev->pers) {
5348                                         err = update_array_info(mddev, &info);
5349                                         if (err) {
5350                                                 printk(KERN_WARNING "md: couldn't update"
5351                                                        " array info. %d\n", err);
5352                                                 goto abort_unlock;
5353                                         }
5354                                         goto done_unlock;
5355                                 }
5356                                 if (!list_empty(&mddev->disks)) {
5357                                         printk(KERN_WARNING
5358                                                "md: array %s already has disks!\n",
5359                                                mdname(mddev));
5360                                         err = -EBUSY;
5361                                         goto abort_unlock;
5362                                 }
5363                                 if (mddev->raid_disks) {
5364                                         printk(KERN_WARNING
5365                                                "md: array %s already initialised!\n",
5366                                                mdname(mddev));
5367                                         err = -EBUSY;
5368                                         goto abort_unlock;
5369                                 }
5370                                 err = set_array_info(mddev, &info);
5371                                 if (err) {
5372                                         printk(KERN_WARNING "md: couldn't set"
5373                                                " array info. %d\n", err);
5374                                         goto abort_unlock;
5375                                 }
5376                         }
5377                         goto done_unlock;
5378
5379                 default:;
5380         }
5381
5382         /*
5383          * Commands querying/configuring an existing array:
5384          */
5385         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
5386          * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
5387         if ((!mddev->raid_disks && !mddev->external)
5388             && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
5389             && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
5390             && cmd != GET_BITMAP_FILE) {
5391                 err = -ENODEV;
5392                 goto abort_unlock;
5393         }
5394
5395         /*
5396          * Commands even a read-only array can execute:
5397          */
5398         switch (cmd)
5399         {
5400                 case GET_ARRAY_INFO:
5401                         err = get_array_info(mddev, argp);
5402                         goto done_unlock;
5403
5404                 case GET_BITMAP_FILE:
5405                         err = get_bitmap_file(mddev, argp);
5406                         goto done_unlock;
5407
5408                 case GET_DISK_INFO:
5409                         err = get_disk_info(mddev, argp);
5410                         goto done_unlock;
5411
5412                 case RESTART_ARRAY_RW:
5413                         err = restart_array(mddev);
5414                         goto done_unlock;
5415
5416                 case STOP_ARRAY:
5417                         err = do_md_stop(mddev, 0, 1);
5418                         goto done_unlock;
5419
5420                 case STOP_ARRAY_RO:
5421                         err = do_md_stop(mddev, 1, 1);
5422                         goto done_unlock;
5423
5424         }
5425
5426         /*
5427          * The remaining ioctls are changing the state of the
5428          * superblock, so we do not allow them on read-only arrays.
5429          * However non-MD ioctls (e.g. get-size) will still come through
5430          * here and hit the 'default' below, so only disallow
5431          * 'md' ioctls, and switch to rw mode if started auto-readonly.
5432          */
5433         if (_IOC_TYPE(cmd) == MD_MAJOR && mddev->ro && mddev->pers) {
5434                 if (mddev->ro == 2) {
5435                         mddev->ro = 0;
5436                         sysfs_notify_dirent(mddev->sysfs_state);
5437                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5438                         md_wakeup_thread(mddev->thread);
5439                 } else {
5440                         err = -EROFS;
5441                         goto abort_unlock;
5442                 }
5443         }
5444
5445         switch (cmd)
5446         {
5447                 case ADD_NEW_DISK:
5448                 {
5449                         mdu_disk_info_t info;
5450                         if (copy_from_user(&info, argp, sizeof(info)))
5451                                 err = -EFAULT;
5452                         else
5453                                 err = add_new_disk(mddev, &info);
5454                         goto done_unlock;
5455                 }
5456
5457                 case HOT_REMOVE_DISK:
5458                         err = hot_remove_disk(mddev, new_decode_dev(arg));
5459                         goto done_unlock;
5460
5461                 case HOT_ADD_DISK:
5462                         err = hot_add_disk(mddev, new_decode_dev(arg));
5463                         goto done_unlock;
5464
5465                 case SET_DISK_FAULTY:
5466                         err = set_disk_faulty(mddev, new_decode_dev(arg));
5467                         goto done_unlock;
5468
5469                 case RUN_ARRAY:
5470                         err = do_md_run(mddev);
5471                         goto done_unlock;
5472
5473                 case SET_BITMAP_FILE:
5474                         err = set_bitmap_file(mddev, (int)arg);
5475                         goto done_unlock;
5476
5477                 default:
5478                         err = -EINVAL;
5479                         goto abort_unlock;
5480         }
5481
5482 done_unlock:
5483 abort_unlock:
5484         if (mddev->hold_active == UNTIL_IOCTL &&
5485             err != -EINVAL)
5486                 mddev->hold_active = 0;
5487         mddev_unlock(mddev);
5488
5489         return err;
5490 done:
5491         if (err)
5492                 MD_BUG();
5493 abort:
5494         return err;
5495 }
5496
5497 static int md_open(struct block_device *bdev, fmode_t mode)
5498 {
5499         /*
5500          * Succeed if we can lock the mddev, which confirms that
5501          * it isn't being stopped right now.
5502          */
5503         mddev_t *mddev = mddev_find(bdev->bd_dev);
5504         int err;
5505
5506         if (mddev->gendisk != bdev->bd_disk) {
5507                 /* we are racing with mddev_put which is discarding this
5508                  * bd_disk.
5509                  */
5510                 mddev_put(mddev);
5511                 /* Wait until bdev->bd_disk is definitely gone */
5512                 flush_scheduled_work();
5513                 /* Then retry the open from the top */
5514                 return -ERESTARTSYS;
5515         }
5516         BUG_ON(mddev != bdev->bd_disk->private_data);
5517
5518         if ((err = mutex_lock_interruptible_nested(&mddev->reconfig_mutex, 1)))
5519                 goto out;
5520
5521         err = 0;
5522         atomic_inc(&mddev->openers);
5523         mddev_unlock(mddev);
5524
5525         check_disk_change(bdev);
5526  out:
5527         return err;
5528 }
5529
5530 static int md_release(struct gendisk *disk, fmode_t mode)
5531 {
5532         mddev_t *mddev = disk->private_data;
5533
5534         BUG_ON(!mddev);
5535         atomic_dec(&mddev->openers);
5536         mddev_put(mddev);
5537
5538         return 0;
5539 }
5540
5541 static int md_media_changed(struct gendisk *disk)
5542 {
5543         mddev_t *mddev = disk->private_data;
5544
5545         return mddev->changed;
5546 }
5547
5548 static int md_revalidate(struct gendisk *disk)
5549 {
5550         mddev_t *mddev = disk->private_data;
5551
5552         mddev->changed = 0;
5553         return 0;
5554 }
5555 static struct block_device_operations md_fops =
5556 {
5557         .owner          = THIS_MODULE,
5558         .open           = md_open,
5559         .release        = md_release,
5560         .locked_ioctl   = md_ioctl,
5561         .getgeo         = md_getgeo,
5562         .media_changed  = md_media_changed,
5563         .revalidate_disk= md_revalidate,
5564 };
5565
5566 static int md_thread(void * arg)
5567 {
5568         mdk_thread_t *thread = arg;
5569
5570         /*
5571          * md_thread is a 'system-thread', it's priority should be very
5572          * high. We avoid resource deadlocks individually in each
5573          * raid personality. (RAID5 does preallocation) We also use RR and
5574          * the very same RT priority as kswapd, thus we will never get
5575          * into a priority inversion deadlock.
5576          *
5577          * we definitely have to have equal or higher priority than
5578          * bdflush, otherwise bdflush will deadlock if there are too
5579          * many dirty RAID5 blocks.
5580          */
5581
5582         allow_signal(SIGKILL);
5583         while (!kthread_should_stop()) {
5584
5585                 /* We need to wait INTERRUPTIBLE so that
5586                  * we don't add to the load-average.
5587                  * That means we need to be sure no signals are
5588                  * pending
5589                  */
5590                 if (signal_pending(current))
5591                         flush_signals(current);
5592
5593                 wait_event_interruptible_timeout
5594                         (thread->wqueue,
5595                          test_bit(THREAD_WAKEUP, &thread->flags)
5596                          || kthread_should_stop(),
5597                          thread->timeout);
5598
5599                 clear_bit(THREAD_WAKEUP, &thread->flags);
5600
5601                 thread->run(thread->mddev);
5602         }
5603
5604         return 0;
5605 }
5606
5607 void md_wakeup_thread(mdk_thread_t *thread)
5608 {
5609         if (thread) {
5610                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
5611                 set_bit(THREAD_WAKEUP, &thread->flags);
5612                 wake_up(&thread->wqueue);
5613         }
5614 }
5615
5616 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
5617                                  const char *name)
5618 {
5619         mdk_thread_t *thread;
5620
5621         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
5622         if (!thread)
5623                 return NULL;
5624
5625         init_waitqueue_head(&thread->wqueue);
5626
5627         thread->run = run;
5628         thread->mddev = mddev;
5629         thread->timeout = MAX_SCHEDULE_TIMEOUT;
5630         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
5631         if (IS_ERR(thread->tsk)) {
5632                 kfree(thread);
5633                 return NULL;
5634         }
5635         return thread;
5636 }
5637
5638 void md_unregister_thread(mdk_thread_t *thread)
5639 {
5640         if (!thread)
5641                 return;
5642         dprintk("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
5643
5644         kthread_stop(thread->tsk);
5645         kfree(thread);
5646 }
5647
5648 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
5649 {
5650         if (!mddev) {
5651                 MD_BUG();
5652                 return;
5653         }
5654
5655         if (!rdev || test_bit(Faulty, &rdev->flags))
5656                 return;
5657
5658         if (mddev->external)
5659                 set_bit(Blocked, &rdev->flags);
5660 /*
5661         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
5662                 mdname(mddev),
5663                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
5664                 __builtin_return_address(0),__builtin_return_address(1),
5665                 __builtin_return_address(2),__builtin_return_address(3));
5666 */
5667         if (!mddev->pers)
5668                 return;
5669         if (!mddev->pers->error_handler)
5670                 return;
5671         mddev->pers->error_handler(mddev,rdev);
5672         if (mddev->degraded)
5673                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
5674         set_bit(StateChanged, &rdev->flags);
5675         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5676         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5677         md_wakeup_thread(mddev->thread);
5678         md_new_event_inintr(mddev);
5679 }
5680
5681 /* seq_file implementation /proc/mdstat */
5682
5683 static void status_unused(struct seq_file *seq)
5684 {
5685         int i = 0;
5686         mdk_rdev_t *rdev;
5687
5688         seq_printf(seq, "unused devices: ");
5689
5690         list_for_each_entry(rdev, &pending_raid_disks, same_set) {
5691                 char b[BDEVNAME_SIZE];
5692                 i++;
5693                 seq_printf(seq, "%s ",
5694                               bdevname(rdev->bdev,b));
5695         }
5696         if (!i)
5697                 seq_printf(seq, "<none>");
5698
5699         seq_printf(seq, "\n");
5700 }
5701
5702
5703 static void status_resync(struct seq_file *seq, mddev_t * mddev)
5704 {
5705         sector_t max_sectors, resync, res;
5706         unsigned long dt, db;
5707         sector_t rt;
5708         int scale;
5709         unsigned int per_milli;
5710
5711         resync = mddev->curr_resync - atomic_read(&mddev->recovery_active);
5712
5713         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
5714                 max_sectors = mddev->resync_max_sectors;
5715         else
5716                 max_sectors = mddev->dev_sectors;
5717
5718         /*
5719          * Should not happen.
5720          */
5721         if (!max_sectors) {
5722                 MD_BUG();
5723                 return;
5724         }
5725         /* Pick 'scale' such that (resync>>scale)*1000 will fit
5726          * in a sector_t, and (max_sectors>>scale) will fit in a
5727          * u32, as those are the requirements for sector_div.
5728          * Thus 'scale' must be at least 10
5729          */
5730         scale = 10;
5731         if (sizeof(sector_t) > sizeof(unsigned long)) {
5732                 while ( max_sectors/2 > (1ULL<<(scale+32)))
5733                         scale++;
5734         }
5735         res = (resync>>scale)*1000;
5736         sector_div(res, (u32)((max_sectors>>scale)+1));
5737
5738         per_milli = res;
5739         {
5740                 int i, x = per_milli/50, y = 20-x;
5741                 seq_printf(seq, "[");
5742                 for (i = 0; i < x; i++)
5743                         seq_printf(seq, "=");
5744                 seq_printf(seq, ">");
5745                 for (i = 0; i < y; i++)
5746                         seq_printf(seq, ".");
5747                 seq_printf(seq, "] ");
5748         }
5749         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
5750                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
5751                     "reshape" :
5752                     (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
5753                      "check" :
5754                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
5755                       "resync" : "recovery"))),
5756                    per_milli/10, per_milli % 10,
5757                    (unsigned long long) resync/2,
5758                    (unsigned long long) max_sectors/2);
5759
5760         /*
5761          * dt: time from mark until now
5762          * db: blocks written from mark until now
5763          * rt: remaining time
5764          *
5765          * rt is a sector_t, so could be 32bit or 64bit.
5766          * So we divide before multiply in case it is 32bit and close
5767          * to the limit.
5768          * We scale the divisor (db) by 32 to avoid loosing precision
5769          * near the end of resync when the number of remaining sectors
5770          * is close to 'db'.
5771          * We then divide rt by 32 after multiplying by db to compensate.
5772          * The '+1' avoids division by zero if db is very small.
5773          */
5774         dt = ((jiffies - mddev->resync_mark) / HZ);
5775         if (!dt) dt++;
5776         db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
5777                 - mddev->resync_mark_cnt;
5778
5779         rt = max_sectors - resync;    /* number of remaining sectors */
5780         sector_div(rt, db/32+1);
5781         rt *= dt;
5782         rt >>= 5;
5783
5784         seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60,
5785                    ((unsigned long)rt % 60)/6);
5786
5787         seq_printf(seq, " speed=%ldK/sec", db/2/dt);
5788 }
5789
5790 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
5791 {
5792         struct list_head *tmp;
5793         loff_t l = *pos;
5794         mddev_t *mddev;
5795
5796         if (l >= 0x10000)
5797                 return NULL;
5798         if (!l--)
5799                 /* header */
5800                 return (void*)1;
5801
5802         spin_lock(&all_mddevs_lock);
5803         list_for_each(tmp,&all_mddevs)
5804                 if (!l--) {
5805                         mddev = list_entry(tmp, mddev_t, all_mddevs);
5806                         mddev_get(mddev);
5807                         spin_unlock(&all_mddevs_lock);
5808                         return mddev;
5809                 }
5810         spin_unlock(&all_mddevs_lock);
5811         if (!l--)
5812                 return (void*)2;/* tail */
5813         return NULL;
5814 }
5815
5816 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
5817 {
5818         struct list_head *tmp;
5819         mddev_t *next_mddev, *mddev = v;
5820         
5821         ++*pos;
5822         if (v == (void*)2)
5823                 return NULL;
5824
5825         spin_lock(&all_mddevs_lock);
5826         if (v == (void*)1)
5827                 tmp = all_mddevs.next;
5828         else
5829                 tmp = mddev->all_mddevs.next;
5830         if (tmp != &all_mddevs)
5831                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
5832         else {
5833                 next_mddev = (void*)2;
5834                 *pos = 0x10000;
5835         }               
5836         spin_unlock(&all_mddevs_lock);
5837
5838         if (v != (void*)1)
5839                 mddev_put(mddev);
5840         return next_mddev;
5841
5842 }
5843
5844 static void md_seq_stop(struct seq_file *seq, void *v)
5845 {
5846         mddev_t *mddev = v;
5847
5848         if (mddev && v != (void*)1 && v != (void*)2)
5849                 mddev_put(mddev);
5850 }
5851
5852 struct mdstat_info {
5853         int event;
5854 };
5855
5856 static int md_seq_show(struct seq_file *seq, void *v)
5857 {
5858         mddev_t *mddev = v;
5859         sector_t sectors;
5860         mdk_rdev_t *rdev;
5861         struct mdstat_info *mi = seq->private;
5862         struct bitmap *bitmap;
5863
5864         if (v == (void*)1) {
5865                 struct mdk_personality *pers;
5866                 seq_printf(seq, "Personalities : ");
5867                 spin_lock(&pers_lock);
5868                 list_for_each_entry(pers, &pers_list, list)
5869                         seq_printf(seq, "[%s] ", pers->name);
5870
5871                 spin_unlock(&pers_lock);
5872                 seq_printf(seq, "\n");
5873                 mi->event = atomic_read(&md_event_count);
5874                 return 0;
5875         }
5876         if (v == (void*)2) {
5877                 status_unused(seq);
5878                 return 0;
5879         }
5880
5881         if (mddev_lock(mddev) < 0)
5882                 return -EINTR;
5883
5884         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
5885                 seq_printf(seq, "%s : %sactive", mdname(mddev),
5886                                                 mddev->pers ? "" : "in");
5887                 if (mddev->pers) {
5888                         if (mddev->ro==1)
5889                                 seq_printf(seq, " (read-only)");
5890                         if (mddev->ro==2)
5891                                 seq_printf(seq, " (auto-read-only)");
5892                         seq_printf(seq, " %s", mddev->pers->name);
5893                 }
5894
5895                 sectors = 0;
5896                 list_for_each_entry(rdev, &mddev->disks, same_set) {
5897                         char b[BDEVNAME_SIZE];
5898                         seq_printf(seq, " %s[%d]",
5899                                 bdevname(rdev->bdev,b), rdev->desc_nr);
5900                         if (test_bit(WriteMostly, &rdev->flags))
5901                                 seq_printf(seq, "(W)");
5902                         if (test_bit(Faulty, &rdev->flags)) {
5903                                 seq_printf(seq, "(F)");
5904                                 continue;
5905                         } else if (rdev->raid_disk < 0)
5906            &nbs