[PATCH] md: allow sync-speed to be controlled per-device
[linux-3.10.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/module.h>
36 #include <linux/config.h>
37 #include <linux/kthread.h>
38 #include <linux/linkage.h>
39 #include <linux/raid/md.h>
40 #include <linux/raid/bitmap.h>
41 #include <linux/sysctl.h>
42 #include <linux/devfs_fs_kernel.h>
43 #include <linux/buffer_head.h> /* for invalidate_bdev */
44 #include <linux/suspend.h>
45 #include <linux/poll.h>
46
47 #include <linux/init.h>
48
49 #include <linux/file.h>
50
51 #ifdef CONFIG_KMOD
52 #include <linux/kmod.h>
53 #endif
54
55 #include <asm/unaligned.h>
56
57 #define MAJOR_NR MD_MAJOR
58 #define MD_DRIVER
59
60 /* 63 partitions with the alternate major number (mdp) */
61 #define MdpMinorShift 6
62
63 #define DEBUG 0
64 #define dprintk(x...) ((void)(DEBUG && printk(x)))
65
66
67 #ifndef MODULE
68 static void autostart_arrays (int part);
69 #endif
70
71 static LIST_HEAD(pers_list);
72 static DEFINE_SPINLOCK(pers_lock);
73
74 /*
75  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
76  * is 1000 KB/sec, so the extra system load does not show up that much.
77  * Increase it if you want to have more _guaranteed_ speed. Note that
78  * the RAID driver will use the maximum available bandwidth if the IO
79  * subsystem is idle. There is also an 'absolute maximum' reconstruction
80  * speed limit - in case reconstruction slows down your system despite
81  * idle IO detection.
82  *
83  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
84  * or /sys/block/mdX/md/sync_speed_{min,max}
85  */
86
87 static int sysctl_speed_limit_min = 1000;
88 static int sysctl_speed_limit_max = 200000;
89 static inline int speed_min(mddev_t *mddev)
90 {
91         return mddev->sync_speed_min ?
92                 mddev->sync_speed_min : sysctl_speed_limit_min;
93 }
94
95 static inline int speed_max(mddev_t *mddev)
96 {
97         return mddev->sync_speed_max ?
98                 mddev->sync_speed_max : sysctl_speed_limit_max;
99 }
100
101 static struct ctl_table_header *raid_table_header;
102
103 static ctl_table raid_table[] = {
104         {
105                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MIN,
106                 .procname       = "speed_limit_min",
107                 .data           = &sysctl_speed_limit_min,
108                 .maxlen         = sizeof(int),
109                 .mode           = 0644,
110                 .proc_handler   = &proc_dointvec,
111         },
112         {
113                 .ctl_name       = DEV_RAID_SPEED_LIMIT_MAX,
114                 .procname       = "speed_limit_max",
115                 .data           = &sysctl_speed_limit_max,
116                 .maxlen         = sizeof(int),
117                 .mode           = 0644,
118                 .proc_handler   = &proc_dointvec,
119         },
120         { .ctl_name = 0 }
121 };
122
123 static ctl_table raid_dir_table[] = {
124         {
125                 .ctl_name       = DEV_RAID,
126                 .procname       = "raid",
127                 .maxlen         = 0,
128                 .mode           = 0555,
129                 .child          = raid_table,
130         },
131         { .ctl_name = 0 }
132 };
133
134 static ctl_table raid_root_table[] = {
135         {
136                 .ctl_name       = CTL_DEV,
137                 .procname       = "dev",
138                 .maxlen         = 0,
139                 .mode           = 0555,
140                 .child          = raid_dir_table,
141         },
142         { .ctl_name = 0 }
143 };
144
145 static struct block_device_operations md_fops;
146
147 static int start_readonly;
148
149 /*
150  * We have a system wide 'event count' that is incremented
151  * on any 'interesting' event, and readers of /proc/mdstat
152  * can use 'poll' or 'select' to find out when the event
153  * count increases.
154  *
155  * Events are:
156  *  start array, stop array, error, add device, remove device,
157  *  start build, activate spare
158  */
159 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
160 static atomic_t md_event_count;
161 static void md_new_event(mddev_t *mddev)
162 {
163         atomic_inc(&md_event_count);
164         wake_up(&md_event_waiters);
165 }
166
167 /*
168  * Enables to iterate over all existing md arrays
169  * all_mddevs_lock protects this list.
170  */
171 static LIST_HEAD(all_mddevs);
172 static DEFINE_SPINLOCK(all_mddevs_lock);
173
174
175 /*
176  * iterates through all used mddevs in the system.
177  * We take care to grab the all_mddevs_lock whenever navigating
178  * the list, and to always hold a refcount when unlocked.
179  * Any code which breaks out of this loop while own
180  * a reference to the current mddev and must mddev_put it.
181  */
182 #define ITERATE_MDDEV(mddev,tmp)                                        \
183                                                                         \
184         for (({ spin_lock(&all_mddevs_lock);                            \
185                 tmp = all_mddevs.next;                                  \
186                 mddev = NULL;});                                        \
187              ({ if (tmp != &all_mddevs)                                 \
188                         mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
189                 spin_unlock(&all_mddevs_lock);                          \
190                 if (mddev) mddev_put(mddev);                            \
191                 mddev = list_entry(tmp, mddev_t, all_mddevs);           \
192                 tmp != &all_mddevs;});                                  \
193              ({ spin_lock(&all_mddevs_lock);                            \
194                 tmp = tmp->next;})                                      \
195                 )
196
197
198 static int md_fail_request (request_queue_t *q, struct bio *bio)
199 {
200         bio_io_error(bio, bio->bi_size);
201         return 0;
202 }
203
204 static inline mddev_t *mddev_get(mddev_t *mddev)
205 {
206         atomic_inc(&mddev->active);
207         return mddev;
208 }
209
210 static void mddev_put(mddev_t *mddev)
211 {
212         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
213                 return;
214         if (!mddev->raid_disks && list_empty(&mddev->disks)) {
215                 list_del(&mddev->all_mddevs);
216                 blk_put_queue(mddev->queue);
217                 kobject_unregister(&mddev->kobj);
218         }
219         spin_unlock(&all_mddevs_lock);
220 }
221
222 static mddev_t * mddev_find(dev_t unit)
223 {
224         mddev_t *mddev, *new = NULL;
225
226  retry:
227         spin_lock(&all_mddevs_lock);
228         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
229                 if (mddev->unit == unit) {
230                         mddev_get(mddev);
231                         spin_unlock(&all_mddevs_lock);
232                         kfree(new);
233                         return mddev;
234                 }
235
236         if (new) {
237                 list_add(&new->all_mddevs, &all_mddevs);
238                 spin_unlock(&all_mddevs_lock);
239                 return new;
240         }
241         spin_unlock(&all_mddevs_lock);
242
243         new = kzalloc(sizeof(*new), GFP_KERNEL);
244         if (!new)
245                 return NULL;
246
247         new->unit = unit;
248         if (MAJOR(unit) == MD_MAJOR)
249                 new->md_minor = MINOR(unit);
250         else
251                 new->md_minor = MINOR(unit) >> MdpMinorShift;
252
253         init_MUTEX(&new->reconfig_sem);
254         INIT_LIST_HEAD(&new->disks);
255         INIT_LIST_HEAD(&new->all_mddevs);
256         init_timer(&new->safemode_timer);
257         atomic_set(&new->active, 1);
258         spin_lock_init(&new->write_lock);
259         init_waitqueue_head(&new->sb_wait);
260
261         new->queue = blk_alloc_queue(GFP_KERNEL);
262         if (!new->queue) {
263                 kfree(new);
264                 return NULL;
265         }
266
267         blk_queue_make_request(new->queue, md_fail_request);
268
269         goto retry;
270 }
271
272 static inline int mddev_lock(mddev_t * mddev)
273 {
274         return down_interruptible(&mddev->reconfig_sem);
275 }
276
277 static inline void mddev_lock_uninterruptible(mddev_t * mddev)
278 {
279         down(&mddev->reconfig_sem);
280 }
281
282 static inline int mddev_trylock(mddev_t * mddev)
283 {
284         return down_trylock(&mddev->reconfig_sem);
285 }
286
287 static inline void mddev_unlock(mddev_t * mddev)
288 {
289         up(&mddev->reconfig_sem);
290
291         md_wakeup_thread(mddev->thread);
292 }
293
294 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
295 {
296         mdk_rdev_t * rdev;
297         struct list_head *tmp;
298
299         ITERATE_RDEV(mddev,rdev,tmp) {
300                 if (rdev->desc_nr == nr)
301                         return rdev;
302         }
303         return NULL;
304 }
305
306 static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
307 {
308         struct list_head *tmp;
309         mdk_rdev_t *rdev;
310
311         ITERATE_RDEV(mddev,rdev,tmp) {
312                 if (rdev->bdev->bd_dev == dev)
313                         return rdev;
314         }
315         return NULL;
316 }
317
318 static struct mdk_personality *find_pers(int level, char *clevel)
319 {
320         struct mdk_personality *pers;
321         list_for_each_entry(pers, &pers_list, list) {
322                 if (level != LEVEL_NONE && pers->level == level)
323                         return pers;
324                 if (strcmp(pers->name, clevel)==0)
325                         return pers;
326         }
327         return NULL;
328 }
329
330 static inline sector_t calc_dev_sboffset(struct block_device *bdev)
331 {
332         sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
333         return MD_NEW_SIZE_BLOCKS(size);
334 }
335
336 static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
337 {
338         sector_t size;
339
340         size = rdev->sb_offset;
341
342         if (chunk_size)
343                 size &= ~((sector_t)chunk_size/1024 - 1);
344         return size;
345 }
346
347 static int alloc_disk_sb(mdk_rdev_t * rdev)
348 {
349         if (rdev->sb_page)
350                 MD_BUG();
351
352         rdev->sb_page = alloc_page(GFP_KERNEL);
353         if (!rdev->sb_page) {
354                 printk(KERN_ALERT "md: out of memory.\n");
355                 return -EINVAL;
356         }
357
358         return 0;
359 }
360
361 static void free_disk_sb(mdk_rdev_t * rdev)
362 {
363         if (rdev->sb_page) {
364                 put_page(rdev->sb_page);
365                 rdev->sb_loaded = 0;
366                 rdev->sb_page = NULL;
367                 rdev->sb_offset = 0;
368                 rdev->size = 0;
369         }
370 }
371
372
373 static int super_written(struct bio *bio, unsigned int bytes_done, int error)
374 {
375         mdk_rdev_t *rdev = bio->bi_private;
376         mddev_t *mddev = rdev->mddev;
377         if (bio->bi_size)
378                 return 1;
379
380         if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
381                 md_error(mddev, rdev);
382
383         if (atomic_dec_and_test(&mddev->pending_writes))
384                 wake_up(&mddev->sb_wait);
385         bio_put(bio);
386         return 0;
387 }
388
389 static int super_written_barrier(struct bio *bio, unsigned int bytes_done, int error)
390 {
391         struct bio *bio2 = bio->bi_private;
392         mdk_rdev_t *rdev = bio2->bi_private;
393         mddev_t *mddev = rdev->mddev;
394         if (bio->bi_size)
395                 return 1;
396
397         if (!test_bit(BIO_UPTODATE, &bio->bi_flags) &&
398             error == -EOPNOTSUPP) {
399                 unsigned long flags;
400                 /* barriers don't appear to be supported :-( */
401                 set_bit(BarriersNotsupp, &rdev->flags);
402                 mddev->barriers_work = 0;
403                 spin_lock_irqsave(&mddev->write_lock, flags);
404                 bio2->bi_next = mddev->biolist;
405                 mddev->biolist = bio2;
406                 spin_unlock_irqrestore(&mddev->write_lock, flags);
407                 wake_up(&mddev->sb_wait);
408                 bio_put(bio);
409                 return 0;
410         }
411         bio_put(bio2);
412         bio->bi_private = rdev;
413         return super_written(bio, bytes_done, error);
414 }
415
416 void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
417                    sector_t sector, int size, struct page *page)
418 {
419         /* write first size bytes of page to sector of rdev
420          * Increment mddev->pending_writes before returning
421          * and decrement it on completion, waking up sb_wait
422          * if zero is reached.
423          * If an error occurred, call md_error
424          *
425          * As we might need to resubmit the request if BIO_RW_BARRIER
426          * causes ENOTSUPP, we allocate a spare bio...
427          */
428         struct bio *bio = bio_alloc(GFP_NOIO, 1);
429         int rw = (1<<BIO_RW) | (1<<BIO_RW_SYNC);
430
431         bio->bi_bdev = rdev->bdev;
432         bio->bi_sector = sector;
433         bio_add_page(bio, page, size, 0);
434         bio->bi_private = rdev;
435         bio->bi_end_io = super_written;
436         bio->bi_rw = rw;
437
438         atomic_inc(&mddev->pending_writes);
439         if (!test_bit(BarriersNotsupp, &rdev->flags)) {
440                 struct bio *rbio;
441                 rw |= (1<<BIO_RW_BARRIER);
442                 rbio = bio_clone(bio, GFP_NOIO);
443                 rbio->bi_private = bio;
444                 rbio->bi_end_io = super_written_barrier;
445                 submit_bio(rw, rbio);
446         } else
447                 submit_bio(rw, bio);
448 }
449
450 void md_super_wait(mddev_t *mddev)
451 {
452         /* wait for all superblock writes that were scheduled to complete.
453          * if any had to be retried (due to BARRIER problems), retry them
454          */
455         DEFINE_WAIT(wq);
456         for(;;) {
457                 prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
458                 if (atomic_read(&mddev->pending_writes)==0)
459                         break;
460                 while (mddev->biolist) {
461                         struct bio *bio;
462                         spin_lock_irq(&mddev->write_lock);
463                         bio = mddev->biolist;
464                         mddev->biolist = bio->bi_next ;
465                         bio->bi_next = NULL;
466                         spin_unlock_irq(&mddev->write_lock);
467                         submit_bio(bio->bi_rw, bio);
468                 }
469                 schedule();
470         }
471         finish_wait(&mddev->sb_wait, &wq);
472 }
473
474 static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
475 {
476         if (bio->bi_size)
477                 return 1;
478
479         complete((struct completion*)bio->bi_private);
480         return 0;
481 }
482
483 int sync_page_io(struct block_device *bdev, sector_t sector, int size,
484                    struct page *page, int rw)
485 {
486         struct bio *bio = bio_alloc(GFP_NOIO, 1);
487         struct completion event;
488         int ret;
489
490         rw |= (1 << BIO_RW_SYNC);
491
492         bio->bi_bdev = bdev;
493         bio->bi_sector = sector;
494         bio_add_page(bio, page, size, 0);
495         init_completion(&event);
496         bio->bi_private = &event;
497         bio->bi_end_io = bi_complete;
498         submit_bio(rw, bio);
499         wait_for_completion(&event);
500
501         ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
502         bio_put(bio);
503         return ret;
504 }
505 EXPORT_SYMBOL_GPL(sync_page_io);
506
507 static int read_disk_sb(mdk_rdev_t * rdev, int size)
508 {
509         char b[BDEVNAME_SIZE];
510         if (!rdev->sb_page) {
511                 MD_BUG();
512                 return -EINVAL;
513         }
514         if (rdev->sb_loaded)
515                 return 0;
516
517
518         if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, size, rdev->sb_page, READ))
519                 goto fail;
520         rdev->sb_loaded = 1;
521         return 0;
522
523 fail:
524         printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
525                 bdevname(rdev->bdev,b));
526         return -EINVAL;
527 }
528
529 static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
530 {
531         if (    (sb1->set_uuid0 == sb2->set_uuid0) &&
532                 (sb1->set_uuid1 == sb2->set_uuid1) &&
533                 (sb1->set_uuid2 == sb2->set_uuid2) &&
534                 (sb1->set_uuid3 == sb2->set_uuid3))
535
536                 return 1;
537
538         return 0;
539 }
540
541
542 static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
543 {
544         int ret;
545         mdp_super_t *tmp1, *tmp2;
546
547         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
548         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
549
550         if (!tmp1 || !tmp2) {
551                 ret = 0;
552                 printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
553                 goto abort;
554         }
555
556         *tmp1 = *sb1;
557         *tmp2 = *sb2;
558
559         /*
560          * nr_disks is not constant
561          */
562         tmp1->nr_disks = 0;
563         tmp2->nr_disks = 0;
564
565         if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
566                 ret = 0;
567         else
568                 ret = 1;
569
570 abort:
571         kfree(tmp1);
572         kfree(tmp2);
573         return ret;
574 }
575
576 static unsigned int calc_sb_csum(mdp_super_t * sb)
577 {
578         unsigned int disk_csum, csum;
579
580         disk_csum = sb->sb_csum;
581         sb->sb_csum = 0;
582         csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
583         sb->sb_csum = disk_csum;
584         return csum;
585 }
586
587
588 /*
589  * Handle superblock details.
590  * We want to be able to handle multiple superblock formats
591  * so we have a common interface to them all, and an array of
592  * different handlers.
593  * We rely on user-space to write the initial superblock, and support
594  * reading and updating of superblocks.
595  * Interface methods are:
596  *   int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
597  *      loads and validates a superblock on dev.
598  *      if refdev != NULL, compare superblocks on both devices
599  *    Return:
600  *      0 - dev has a superblock that is compatible with refdev
601  *      1 - dev has a superblock that is compatible and newer than refdev
602  *          so dev should be used as the refdev in future
603  *     -EINVAL superblock incompatible or invalid
604  *     -othererror e.g. -EIO
605  *
606  *   int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
607  *      Verify that dev is acceptable into mddev.
608  *       The first time, mddev->raid_disks will be 0, and data from
609  *       dev should be merged in.  Subsequent calls check that dev
610  *       is new enough.  Return 0 or -EINVAL
611  *
612  *   void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
613  *     Update the superblock for rdev with data in mddev
614  *     This does not write to disc.
615  *
616  */
617
618 struct super_type  {
619         char            *name;
620         struct module   *owner;
621         int             (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
622         int             (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
623         void            (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
624 };
625
626 /*
627  * load_super for 0.90.0 
628  */
629 static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
630 {
631         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
632         mdp_super_t *sb;
633         int ret;
634         sector_t sb_offset;
635
636         /*
637          * Calculate the position of the superblock,
638          * it's at the end of the disk.
639          *
640          * It also happens to be a multiple of 4Kb.
641          */
642         sb_offset = calc_dev_sboffset(rdev->bdev);
643         rdev->sb_offset = sb_offset;
644
645         ret = read_disk_sb(rdev, MD_SB_BYTES);
646         if (ret) return ret;
647
648         ret = -EINVAL;
649
650         bdevname(rdev->bdev, b);
651         sb = (mdp_super_t*)page_address(rdev->sb_page);
652
653         if (sb->md_magic != MD_SB_MAGIC) {
654                 printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
655                        b);
656                 goto abort;
657         }
658
659         if (sb->major_version != 0 ||
660             sb->minor_version != 90) {
661                 printk(KERN_WARNING "Bad version number %d.%d on %s\n",
662                         sb->major_version, sb->minor_version,
663                         b);
664                 goto abort;
665         }
666
667         if (sb->raid_disks <= 0)
668                 goto abort;
669
670         if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
671                 printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
672                         b);
673                 goto abort;
674         }
675
676         rdev->preferred_minor = sb->md_minor;
677         rdev->data_offset = 0;
678         rdev->sb_size = MD_SB_BYTES;
679
680         if (sb->level == LEVEL_MULTIPATH)
681                 rdev->desc_nr = -1;
682         else
683                 rdev->desc_nr = sb->this_disk.number;
684
685         if (refdev == 0)
686                 ret = 1;
687         else {
688                 __u64 ev1, ev2;
689                 mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
690                 if (!uuid_equal(refsb, sb)) {
691                         printk(KERN_WARNING "md: %s has different UUID to %s\n",
692                                 b, bdevname(refdev->bdev,b2));
693                         goto abort;
694                 }
695                 if (!sb_equal(refsb, sb)) {
696                         printk(KERN_WARNING "md: %s has same UUID"
697                                " but different superblock to %s\n",
698                                b, bdevname(refdev->bdev, b2));
699                         goto abort;
700                 }
701                 ev1 = md_event(sb);
702                 ev2 = md_event(refsb);
703                 if (ev1 > ev2)
704                         ret = 1;
705                 else 
706                         ret = 0;
707         }
708         rdev->size = calc_dev_size(rdev, sb->chunk_size);
709
710         if (rdev->size < sb->size && sb->level > 1)
711                 /* "this cannot possibly happen" ... */
712                 ret = -EINVAL;
713
714  abort:
715         return ret;
716 }
717
718 /*
719  * validate_super for 0.90.0
720  */
721 static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
722 {
723         mdp_disk_t *desc;
724         mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
725
726         rdev->raid_disk = -1;
727         rdev->flags = 0;
728         if (mddev->raid_disks == 0) {
729                 mddev->major_version = 0;
730                 mddev->minor_version = sb->minor_version;
731                 mddev->patch_version = sb->patch_version;
732                 mddev->persistent = ! sb->not_persistent;
733                 mddev->chunk_size = sb->chunk_size;
734                 mddev->ctime = sb->ctime;
735                 mddev->utime = sb->utime;
736                 mddev->level = sb->level;
737                 mddev->clevel[0] = 0;
738                 mddev->layout = sb->layout;
739                 mddev->raid_disks = sb->raid_disks;
740                 mddev->size = sb->size;
741                 mddev->events = md_event(sb);
742                 mddev->bitmap_offset = 0;
743                 mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
744
745                 if (sb->state & (1<<MD_SB_CLEAN))
746                         mddev->recovery_cp = MaxSector;
747                 else {
748                         if (sb->events_hi == sb->cp_events_hi && 
749                                 sb->events_lo == sb->cp_events_lo) {
750                                 mddev->recovery_cp = sb->recovery_cp;
751                         } else
752                                 mddev->recovery_cp = 0;
753                 }
754
755                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
756                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
757                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
758                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
759
760                 mddev->max_disks = MD_SB_DISKS;
761
762                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
763                     mddev->bitmap_file == NULL) {
764                         if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6
765                             && mddev->level != 10) {
766                                 /* FIXME use a better test */
767                                 printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
768                                 return -EINVAL;
769                         }
770                         mddev->bitmap_offset = mddev->default_bitmap_offset;
771                 }
772
773         } else if (mddev->pers == NULL) {
774                 /* Insist on good event counter while assembling */
775                 __u64 ev1 = md_event(sb);
776                 ++ev1;
777                 if (ev1 < mddev->events) 
778                         return -EINVAL;
779         } else if (mddev->bitmap) {
780                 /* if adding to array with a bitmap, then we can accept an
781                  * older device ... but not too old.
782                  */
783                 __u64 ev1 = md_event(sb);
784                 if (ev1 < mddev->bitmap->events_cleared)
785                         return 0;
786         } else /* just a hot-add of a new device, leave raid_disk at -1 */
787                 return 0;
788
789         if (mddev->level != LEVEL_MULTIPATH) {
790                 desc = sb->disks + rdev->desc_nr;
791
792                 if (desc->state & (1<<MD_DISK_FAULTY))
793                         set_bit(Faulty, &rdev->flags);
794                 else if (desc->state & (1<<MD_DISK_SYNC) &&
795                          desc->raid_disk < mddev->raid_disks) {
796                         set_bit(In_sync, &rdev->flags);
797                         rdev->raid_disk = desc->raid_disk;
798                 }
799                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
800                         set_bit(WriteMostly, &rdev->flags);
801         } else /* MULTIPATH are always insync */
802                 set_bit(In_sync, &rdev->flags);
803         return 0;
804 }
805
806 /*
807  * sync_super for 0.90.0
808  */
809 static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
810 {
811         mdp_super_t *sb;
812         struct list_head *tmp;
813         mdk_rdev_t *rdev2;
814         int next_spare = mddev->raid_disks;
815
816
817         /* make rdev->sb match mddev data..
818          *
819          * 1/ zero out disks
820          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
821          * 3/ any empty disks < next_spare become removed
822          *
823          * disks[0] gets initialised to REMOVED because
824          * we cannot be sure from other fields if it has
825          * been initialised or not.
826          */
827         int i;
828         int active=0, working=0,failed=0,spare=0,nr_disks=0;
829
830         rdev->sb_size = MD_SB_BYTES;
831
832         sb = (mdp_super_t*)page_address(rdev->sb_page);
833
834         memset(sb, 0, sizeof(*sb));
835
836         sb->md_magic = MD_SB_MAGIC;
837         sb->major_version = mddev->major_version;
838         sb->minor_version = mddev->minor_version;
839         sb->patch_version = mddev->patch_version;
840         sb->gvalid_words  = 0; /* ignored */
841         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
842         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
843         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
844         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
845
846         sb->ctime = mddev->ctime;
847         sb->level = mddev->level;
848         sb->size  = mddev->size;
849         sb->raid_disks = mddev->raid_disks;
850         sb->md_minor = mddev->md_minor;
851         sb->not_persistent = !mddev->persistent;
852         sb->utime = mddev->utime;
853         sb->state = 0;
854         sb->events_hi = (mddev->events>>32);
855         sb->events_lo = (u32)mddev->events;
856
857         if (mddev->in_sync)
858         {
859                 sb->recovery_cp = mddev->recovery_cp;
860                 sb->cp_events_hi = (mddev->events>>32);
861                 sb->cp_events_lo = (u32)mddev->events;
862                 if (mddev->recovery_cp == MaxSector)
863                         sb->state = (1<< MD_SB_CLEAN);
864         } else
865                 sb->recovery_cp = 0;
866
867         sb->layout = mddev->layout;
868         sb->chunk_size = mddev->chunk_size;
869
870         if (mddev->bitmap && mddev->bitmap_file == NULL)
871                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
872
873         sb->disks[0].state = (1<<MD_DISK_REMOVED);
874         ITERATE_RDEV(mddev,rdev2,tmp) {
875                 mdp_disk_t *d;
876                 int desc_nr;
877                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
878                     && !test_bit(Faulty, &rdev2->flags))
879                         desc_nr = rdev2->raid_disk;
880                 else
881                         desc_nr = next_spare++;
882                 rdev2->desc_nr = desc_nr;
883                 d = &sb->disks[rdev2->desc_nr];
884                 nr_disks++;
885                 d->number = rdev2->desc_nr;
886                 d->major = MAJOR(rdev2->bdev->bd_dev);
887                 d->minor = MINOR(rdev2->bdev->bd_dev);
888                 if (rdev2->raid_disk >= 0 && test_bit(In_sync, &rdev2->flags)
889                     && !test_bit(Faulty, &rdev2->flags))
890                         d->raid_disk = rdev2->raid_disk;
891                 else
892                         d->raid_disk = rdev2->desc_nr; /* compatibility */
893                 if (test_bit(Faulty, &rdev2->flags)) {
894                         d->state = (1<<MD_DISK_FAULTY);
895                         failed++;
896                 } else if (test_bit(In_sync, &rdev2->flags)) {
897                         d->state = (1<<MD_DISK_ACTIVE);
898                         d->state |= (1<<MD_DISK_SYNC);
899                         active++;
900                         working++;
901                 } else {
902                         d->state = 0;
903                         spare++;
904                         working++;
905                 }
906                 if (test_bit(WriteMostly, &rdev2->flags))
907                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
908         }
909         /* now set the "removed" and "faulty" bits on any missing devices */
910         for (i=0 ; i < mddev->raid_disks ; i++) {
911                 mdp_disk_t *d = &sb->disks[i];
912                 if (d->state == 0 && d->number == 0) {
913                         d->number = i;
914                         d->raid_disk = i;
915                         d->state = (1<<MD_DISK_REMOVED);
916                         d->state |= (1<<MD_DISK_FAULTY);
917                         failed++;
918                 }
919         }
920         sb->nr_disks = nr_disks;
921         sb->active_disks = active;
922         sb->working_disks = working;
923         sb->failed_disks = failed;
924         sb->spare_disks = spare;
925
926         sb->this_disk = sb->disks[rdev->desc_nr];
927         sb->sb_csum = calc_sb_csum(sb);
928 }
929
930 /*
931  * version 1 superblock
932  */
933
934 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
935 {
936         unsigned int disk_csum, csum;
937         unsigned long long newcsum;
938         int size = 256 + le32_to_cpu(sb->max_dev)*2;
939         unsigned int *isuper = (unsigned int*)sb;
940         int i;
941
942         disk_csum = sb->sb_csum;
943         sb->sb_csum = 0;
944         newcsum = 0;
945         for (i=0; size>=4; size -= 4 )
946                 newcsum += le32_to_cpu(*isuper++);
947
948         if (size == 2)
949                 newcsum += le16_to_cpu(*(unsigned short*) isuper);
950
951         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
952         sb->sb_csum = disk_csum;
953         return cpu_to_le32(csum);
954 }
955
956 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
957 {
958         struct mdp_superblock_1 *sb;
959         int ret;
960         sector_t sb_offset;
961         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
962         int bmask;
963
964         /*
965          * Calculate the position of the superblock.
966          * It is always aligned to a 4K boundary and
967          * depeding on minor_version, it can be:
968          * 0: At least 8K, but less than 12K, from end of device
969          * 1: At start of device
970          * 2: 4K from start of device.
971          */
972         switch(minor_version) {
973         case 0:
974                 sb_offset = rdev->bdev->bd_inode->i_size >> 9;
975                 sb_offset -= 8*2;
976                 sb_offset &= ~(sector_t)(4*2-1);
977                 /* convert from sectors to K */
978                 sb_offset /= 2;
979                 break;
980         case 1:
981                 sb_offset = 0;
982                 break;
983         case 2:
984                 sb_offset = 4;
985                 break;
986         default:
987                 return -EINVAL;
988         }
989         rdev->sb_offset = sb_offset;
990
991         /* superblock is rarely larger than 1K, but it can be larger,
992          * and it is safe to read 4k, so we do that
993          */
994         ret = read_disk_sb(rdev, 4096);
995         if (ret) return ret;
996
997
998         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
999
1000         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1001             sb->major_version != cpu_to_le32(1) ||
1002             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1003             le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
1004             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1005                 return -EINVAL;
1006
1007         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1008                 printk("md: invalid superblock checksum on %s\n",
1009                         bdevname(rdev->bdev,b));
1010                 return -EINVAL;
1011         }
1012         if (le64_to_cpu(sb->data_size) < 10) {
1013                 printk("md: data_size too small on %s\n",
1014                        bdevname(rdev->bdev,b));
1015                 return -EINVAL;
1016         }
1017         rdev->preferred_minor = 0xffff;
1018         rdev->data_offset = le64_to_cpu(sb->data_offset);
1019         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1020
1021         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1022         bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
1023         if (rdev->sb_size & bmask)
1024                 rdev-> sb_size = (rdev->sb_size | bmask)+1;
1025
1026         if (refdev == 0)
1027                 return 1;
1028         else {
1029                 __u64 ev1, ev2;
1030                 struct mdp_superblock_1 *refsb = 
1031                         (struct mdp_superblock_1*)page_address(refdev->sb_page);
1032
1033                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1034                     sb->level != refsb->level ||
1035                     sb->layout != refsb->layout ||
1036                     sb->chunksize != refsb->chunksize) {
1037                         printk(KERN_WARNING "md: %s has strangely different"
1038                                 " superblock to %s\n",
1039                                 bdevname(rdev->bdev,b),
1040                                 bdevname(refdev->bdev,b2));
1041                         return -EINVAL;
1042                 }
1043                 ev1 = le64_to_cpu(sb->events);
1044                 ev2 = le64_to_cpu(refsb->events);
1045
1046                 if (ev1 > ev2)
1047                         return 1;
1048         }
1049         if (minor_version) 
1050                 rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
1051         else
1052                 rdev->size = rdev->sb_offset;
1053         if (rdev->size < le64_to_cpu(sb->data_size)/2)
1054                 return -EINVAL;
1055         rdev->size = le64_to_cpu(sb->data_size)/2;
1056         if (le32_to_cpu(sb->chunksize))
1057                 rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
1058
1059         if (le32_to_cpu(sb->size) > rdev->size*2)
1060                 return -EINVAL;
1061         return 0;
1062 }
1063
1064 static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
1065 {
1066         struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1067
1068         rdev->raid_disk = -1;
1069         rdev->flags = 0;
1070         if (mddev->raid_disks == 0) {
1071                 mddev->major_version = 1;
1072                 mddev->patch_version = 0;
1073                 mddev->persistent = 1;
1074                 mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
1075                 mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1076                 mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1077                 mddev->level = le32_to_cpu(sb->level);
1078                 mddev->clevel[0] = 0;
1079                 mddev->layout = le32_to_cpu(sb->layout);
1080                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1081                 mddev->size = le64_to_cpu(sb->size)/2;
1082                 mddev->events = le64_to_cpu(sb->events);
1083                 mddev->bitmap_offset = 0;
1084                 mddev->default_bitmap_offset = 1024;
1085                 
1086                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1087                 memcpy(mddev->uuid, sb->set_uuid, 16);
1088
1089                 mddev->max_disks =  (4096-256)/2;
1090
1091                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1092                     mddev->bitmap_file == NULL ) {
1093                         if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6
1094                             && mddev->level != 10) {
1095                                 printk(KERN_WARNING "md: bitmaps not supported for this level.\n");
1096                                 return -EINVAL;
1097                         }
1098                         mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
1099                 }
1100         } else if (mddev->pers == NULL) {
1101                 /* Insist of good event counter while assembling */
1102                 __u64 ev1 = le64_to_cpu(sb->events);
1103                 ++ev1;
1104                 if (ev1 < mddev->events)
1105                         return -EINVAL;
1106         } else if (mddev->bitmap) {
1107                 /* If adding to array with a bitmap, then we can accept an
1108                  * older device, but not too old.
1109                  */
1110                 __u64 ev1 = le64_to_cpu(sb->events);
1111                 if (ev1 < mddev->bitmap->events_cleared)
1112                         return 0;
1113         } else /* just a hot-add of a new device, leave raid_disk at -1 */
1114                 return 0;
1115
1116         if (mddev->level != LEVEL_MULTIPATH) {
1117                 int role;
1118                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1119                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1120                 switch(role) {
1121                 case 0xffff: /* spare */
1122                         break;
1123                 case 0xfffe: /* faulty */
1124                         set_bit(Faulty, &rdev->flags);
1125                         break;
1126                 default:
1127                         set_bit(In_sync, &rdev->flags);
1128                         rdev->raid_disk = role;
1129                         break;
1130                 }
1131                 if (sb->devflags & WriteMostly1)
1132                         set_bit(WriteMostly, &rdev->flags);
1133         } else /* MULTIPATH are always insync */
1134                 set_bit(In_sync, &rdev->flags);
1135
1136         return 0;
1137 }
1138
1139 static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
1140 {
1141         struct mdp_superblock_1 *sb;
1142         struct list_head *tmp;
1143         mdk_rdev_t *rdev2;
1144         int max_dev, i;
1145         /* make rdev->sb match mddev and rdev data. */
1146
1147         sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
1148
1149         sb->feature_map = 0;
1150         sb->pad0 = 0;
1151         memset(sb->pad1, 0, sizeof(sb->pad1));
1152         memset(sb->pad2, 0, sizeof(sb->pad2));
1153         memset(sb->pad3, 0, sizeof(sb->pad3));
1154
1155         sb->utime = cpu_to_le64((__u64)mddev->utime);
1156         sb->events = cpu_to_le64(mddev->events);
1157         if (mddev->in_sync)
1158                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1159         else
1160                 sb->resync_offset = cpu_to_le64(0);
1161
1162         sb->cnt_corrected_read = atomic_read(&rdev->corrected_errors);
1163
1164         if (mddev->bitmap && mddev->bitmap_file == NULL) {
1165                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
1166                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1167         }
1168
1169         max_dev = 0;
1170         ITERATE_RDEV(mddev,rdev2,tmp)
1171                 if (rdev2->desc_nr+1 > max_dev)
1172                         max_dev = rdev2->desc_nr+1;
1173         
1174         sb->max_dev = cpu_to_le32(max_dev);
1175         for (i=0; i<max_dev;i++)
1176                 sb->dev_roles[i] = cpu_to_le16(0xfffe);
1177         
1178         ITERATE_RDEV(mddev,rdev2,tmp) {
1179                 i = rdev2->desc_nr;
1180                 if (test_bit(Faulty, &rdev2->flags))
1181                         sb->dev_roles[i] = cpu_to_le16(0xfffe);
1182                 else if (test_bit(In_sync, &rdev2->flags))
1183                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1184                 else
1185                         sb->dev_roles[i] = cpu_to_le16(0xffff);
1186         }
1187
1188         sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
1189         sb->sb_csum = calc_sb_1_csum(sb);
1190 }
1191
1192
1193 static struct super_type super_types[] = {
1194         [0] = {
1195                 .name   = "0.90.0",
1196                 .owner  = THIS_MODULE,
1197                 .load_super     = super_90_load,
1198                 .validate_super = super_90_validate,
1199                 .sync_super     = super_90_sync,
1200         },
1201         [1] = {
1202                 .name   = "md-1",
1203                 .owner  = THIS_MODULE,
1204                 .load_super     = super_1_load,
1205                 .validate_super = super_1_validate,
1206                 .sync_super     = super_1_sync,
1207         },
1208 };
1209         
1210 static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
1211 {
1212         struct list_head *tmp;
1213         mdk_rdev_t *rdev;
1214
1215         ITERATE_RDEV(mddev,rdev,tmp)
1216                 if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
1217                         return rdev;
1218
1219         return NULL;
1220 }
1221
1222 static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
1223 {
1224         struct list_head *tmp;
1225         mdk_rdev_t *rdev;
1226
1227         ITERATE_RDEV(mddev1,rdev,tmp)
1228                 if (match_dev_unit(mddev2, rdev))
1229                         return 1;
1230
1231         return 0;
1232 }
1233
1234 static LIST_HEAD(pending_raid_disks);
1235
1236 static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
1237 {
1238         mdk_rdev_t *same_pdev;
1239         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1240         struct kobject *ko;
1241
1242         if (rdev->mddev) {
1243                 MD_BUG();
1244                 return -EINVAL;
1245         }
1246         /* make sure rdev->size exceeds mddev->size */
1247         if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
1248                 if (mddev->pers)
1249                         /* Cannot change size, so fail */
1250                         return -ENOSPC;
1251                 else
1252                         mddev->size = rdev->size;
1253         }
1254         same_pdev = match_dev_unit(mddev, rdev);
1255         if (same_pdev)
1256                 printk(KERN_WARNING
1257                         "%s: WARNING: %s appears to be on the same physical"
1258                         " disk as %s. True\n     protection against single-disk"
1259                         " failure might be compromised.\n",
1260                         mdname(mddev), bdevname(rdev->bdev,b),
1261                         bdevname(same_pdev->bdev,b2));
1262
1263         /* Verify rdev->desc_nr is unique.
1264          * If it is -1, assign a free number, else
1265          * check number is not in use
1266          */
1267         if (rdev->desc_nr < 0) {
1268                 int choice = 0;
1269                 if (mddev->pers) choice = mddev->raid_disks;
1270                 while (find_rdev_nr(mddev, choice))
1271                         choice++;
1272                 rdev->desc_nr = choice;
1273         } else {
1274                 if (find_rdev_nr(mddev, rdev->desc_nr))
1275                         return -EBUSY;
1276         }
1277         bdevname(rdev->bdev,b);
1278         if (kobject_set_name(&rdev->kobj, "dev-%s", b) < 0)
1279                 return -ENOMEM;
1280                         
1281         list_add(&rdev->same_set, &mddev->disks);
1282         rdev->mddev = mddev;
1283         printk(KERN_INFO "md: bind<%s>\n", b);
1284
1285         rdev->kobj.parent = &mddev->kobj;
1286         kobject_add(&rdev->kobj);
1287
1288         if (rdev->bdev->bd_part)
1289                 ko = &rdev->bdev->bd_part->kobj;
1290         else
1291                 ko = &rdev->bdev->bd_disk->kobj;
1292         sysfs_create_link(&rdev->kobj, ko, "block");
1293         return 0;
1294 }
1295
1296 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
1297 {
1298         char b[BDEVNAME_SIZE];
1299         if (!rdev->mddev) {
1300                 MD_BUG();
1301                 return;
1302         }
1303         list_del_init(&rdev->same_set);
1304         printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
1305         rdev->mddev = NULL;
1306         sysfs_remove_link(&rdev->kobj, "block");
1307         kobject_del(&rdev->kobj);
1308 }
1309
1310 /*
1311  * prevent the device from being mounted, repartitioned or
1312  * otherwise reused by a RAID array (or any other kernel
1313  * subsystem), by bd_claiming the device.
1314  */
1315 static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
1316 {
1317         int err = 0;
1318         struct block_device *bdev;
1319         char b[BDEVNAME_SIZE];
1320
1321         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
1322         if (IS_ERR(bdev)) {
1323                 printk(KERN_ERR "md: could not open %s.\n",
1324                         __bdevname(dev, b));
1325                 return PTR_ERR(bdev);
1326         }
1327         err = bd_claim(bdev, rdev);
1328         if (err) {
1329                 printk(KERN_ERR "md: could not bd_claim %s.\n",
1330                         bdevname(bdev, b));
1331                 blkdev_put(bdev);
1332                 return err;
1333         }
1334         rdev->bdev = bdev;
1335         return err;
1336 }
1337
1338 static void unlock_rdev(mdk_rdev_t *rdev)
1339 {
1340         struct block_device *bdev = rdev->bdev;
1341         rdev->bdev = NULL;
1342         if (!bdev)
1343                 MD_BUG();
1344         bd_release(bdev);
1345         blkdev_put(bdev);
1346 }
1347
1348 void md_autodetect_dev(dev_t dev);
1349
1350 static void export_rdev(mdk_rdev_t * rdev)
1351 {
1352         char b[BDEVNAME_SIZE];
1353         printk(KERN_INFO "md: export_rdev(%s)\n",
1354                 bdevname(rdev->bdev,b));
1355         if (rdev->mddev)
1356                 MD_BUG();
1357         free_disk_sb(rdev);
1358         list_del_init(&rdev->same_set);
1359 #ifndef MODULE
1360         md_autodetect_dev(rdev->bdev->bd_dev);
1361 #endif
1362         unlock_rdev(rdev);
1363         kobject_put(&rdev->kobj);
1364 }
1365
1366 static void kick_rdev_from_array(mdk_rdev_t * rdev)
1367 {
1368         unbind_rdev_from_array(rdev);
1369         export_rdev(rdev);
1370 }
1371
1372 static void export_array(mddev_t *mddev)
1373 {
1374         struct list_head *tmp;
1375         mdk_rdev_t *rdev;
1376
1377         ITERATE_RDEV(mddev,rdev,tmp) {
1378                 if (!rdev->mddev) {
1379                         MD_BUG();
1380                         continue;
1381                 }
1382                 kick_rdev_from_array(rdev);
1383         }
1384         if (!list_empty(&mddev->disks))
1385                 MD_BUG();
1386         mddev->raid_disks = 0;
1387         mddev->major_version = 0;
1388 }
1389
1390 static void print_desc(mdp_disk_t *desc)
1391 {
1392         printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
1393                 desc->major,desc->minor,desc->raid_disk,desc->state);
1394 }
1395
1396 static void print_sb(mdp_super_t *sb)
1397 {
1398         int i;
1399
1400         printk(KERN_INFO 
1401                 "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
1402                 sb->major_version, sb->minor_version, sb->patch_version,
1403                 sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
1404                 sb->ctime);
1405         printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
1406                 sb->level, sb->size, sb->nr_disks, sb->raid_disks,
1407                 sb->md_minor, sb->layout, sb->chunk_size);
1408         printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
1409                 " FD:%d SD:%d CSUM:%08x E:%08lx\n",
1410                 sb->utime, sb->state, sb->active_disks, sb->working_disks,
1411                 sb->failed_disks, sb->spare_disks,
1412                 sb->sb_csum, (unsigned long)sb->events_lo);
1413
1414         printk(KERN_INFO);
1415         for (i = 0; i < MD_SB_DISKS; i++) {
1416                 mdp_disk_t *desc;
1417
1418                 desc = sb->disks + i;
1419                 if (desc->number || desc->major || desc->minor ||
1420                     desc->raid_disk || (desc->state && (desc->state != 4))) {
1421                         printk("     D %2d: ", i);
1422                         print_desc(desc);
1423                 }
1424         }
1425         printk(KERN_INFO "md:     THIS: ");
1426         print_desc(&sb->this_disk);
1427
1428 }
1429
1430 static void print_rdev(mdk_rdev_t *rdev)
1431 {
1432         char b[BDEVNAME_SIZE];
1433         printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
1434                 bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
1435                 test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
1436                 rdev->desc_nr);
1437         if (rdev->sb_loaded) {
1438                 printk(KERN_INFO "md: rdev superblock:\n");
1439                 print_sb((mdp_super_t*)page_address(rdev->sb_page));
1440         } else
1441                 printk(KERN_INFO "md: no rdev superblock!\n");
1442 }
1443
1444 void md_print_devices(void)
1445 {
1446         struct list_head *tmp, *tmp2;
1447         mdk_rdev_t *rdev;
1448         mddev_t *mddev;
1449         char b[BDEVNAME_SIZE];
1450
1451         printk("\n");
1452         printk("md:     **********************************\n");
1453         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
1454         printk("md:     **********************************\n");
1455         ITERATE_MDDEV(mddev,tmp) {
1456
1457                 if (mddev->bitmap)
1458                         bitmap_print_sb(mddev->bitmap);
1459                 else
1460                         printk("%s: ", mdname(mddev));
1461                 ITERATE_RDEV(mddev,rdev,tmp2)
1462                         printk("<%s>", bdevname(rdev->bdev,b));
1463                 printk("\n");
1464
1465                 ITERATE_RDEV(mddev,rdev,tmp2)
1466                         print_rdev(rdev);
1467         }
1468         printk("md:     **********************************\n");
1469         printk("\n");
1470 }
1471
1472
1473 static void sync_sbs(mddev_t * mddev)
1474 {
1475         mdk_rdev_t *rdev;
1476         struct list_head *tmp;
1477
1478         ITERATE_RDEV(mddev,rdev,tmp) {
1479                 super_types[mddev->major_version].
1480                         sync_super(mddev, rdev);
1481                 rdev->sb_loaded = 1;
1482         }
1483 }
1484
1485 static void md_update_sb(mddev_t * mddev)
1486 {
1487         int err;
1488         struct list_head *tmp;
1489         mdk_rdev_t *rdev;
1490         int sync_req;
1491
1492 repeat:
1493         spin_lock_irq(&mddev->write_lock);
1494         sync_req = mddev->in_sync;
1495         mddev->utime = get_seconds();
1496         mddev->events ++;
1497
1498         if (!mddev->events) {
1499                 /*
1500                  * oops, this 64-bit counter should never wrap.
1501                  * Either we are in around ~1 trillion A.C., assuming
1502                  * 1 reboot per second, or we have a bug:
1503                  */
1504                 MD_BUG();
1505                 mddev->events --;
1506         }
1507         mddev->sb_dirty = 2;
1508         sync_sbs(mddev);
1509
1510         /*
1511          * do not write anything to disk if using
1512          * nonpersistent superblocks
1513          */
1514         if (!mddev->persistent) {
1515                 mddev->sb_dirty = 0;
1516                 spin_unlock_irq(&mddev->write_lock);
1517                 wake_up(&mddev->sb_wait);
1518                 return;
1519         }
1520         spin_unlock_irq(&mddev->write_lock);
1521
1522         dprintk(KERN_INFO 
1523                 "md: updating %s RAID superblock on device (in sync %d)\n",
1524                 mdname(mddev),mddev->in_sync);
1525
1526         err = bitmap_update_sb(mddev->bitmap);
1527         ITERATE_RDEV(mddev,rdev,tmp) {
1528                 char b[BDEVNAME_SIZE];
1529                 dprintk(KERN_INFO "md: ");
1530                 if (test_bit(Faulty, &rdev->flags))
1531                         dprintk("(skipping faulty ");
1532
1533                 dprintk("%s ", bdevname(rdev->bdev,b));
1534                 if (!test_bit(Faulty, &rdev->flags)) {
1535                         md_super_write(mddev,rdev,
1536                                        rdev->sb_offset<<1, rdev->sb_size,
1537                                        rdev->sb_page);
1538                         dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
1539                                 bdevname(rdev->bdev,b),
1540                                 (unsigned long long)rdev->sb_offset);
1541
1542                 } else
1543                         dprintk(")\n");
1544                 if (mddev->level == LEVEL_MULTIPATH)
1545                         /* only need to write one superblock... */
1546                         break;
1547         }
1548         md_super_wait(mddev);
1549         /* if there was a failure, sb_dirty was set to 1, and we re-write super */
1550
1551         spin_lock_irq(&mddev->write_lock);
1552         if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
1553                 /* have to write it out again */
1554                 spin_unlock_irq(&mddev->write_lock);
1555                 goto repeat;
1556         }
1557         mddev->sb_dirty = 0;
1558         spin_unlock_irq(&mddev->write_lock);
1559         wake_up(&mddev->sb_wait);
1560
1561 }
1562
1563 /* words written to sysfs files may, or my not, be \n terminated.
1564  * We want to accept with case. For this we use cmd_match.
1565  */
1566 static int cmd_match(const char *cmd, const char *str)
1567 {
1568         /* See if cmd, written into a sysfs file, matches
1569          * str.  They must either be the same, or cmd can
1570          * have a trailing newline
1571          */
1572         while (*cmd && *str && *cmd == *str) {
1573                 cmd++;
1574                 str++;
1575         }
1576         if (*cmd == '\n')
1577                 cmd++;
1578         if (*str || *cmd)
1579                 return 0;
1580         return 1;
1581 }
1582
1583 struct rdev_sysfs_entry {
1584         struct attribute attr;
1585         ssize_t (*show)(mdk_rdev_t *, char *);
1586         ssize_t (*store)(mdk_rdev_t *, const char *, size_t);
1587 };
1588
1589 static ssize_t
1590 state_show(mdk_rdev_t *rdev, char *page)
1591 {
1592         char *sep = "";
1593         int len=0;
1594
1595         if (test_bit(Faulty, &rdev->flags)) {
1596                 len+= sprintf(page+len, "%sfaulty",sep);
1597                 sep = ",";
1598         }
1599         if (test_bit(In_sync, &rdev->flags)) {
1600                 len += sprintf(page+len, "%sin_sync",sep);
1601                 sep = ",";
1602         }
1603         if (!test_bit(Faulty, &rdev->flags) &&
1604             !test_bit(In_sync, &rdev->flags)) {
1605                 len += sprintf(page+len, "%sspare", sep);
1606                 sep = ",";
1607         }
1608         return len+sprintf(page+len, "\n");
1609 }
1610
1611 static struct rdev_sysfs_entry
1612 rdev_state = __ATTR_RO(state);
1613
1614 static ssize_t
1615 super_show(mdk_rdev_t *rdev, char *page)
1616 {
1617         if (rdev->sb_loaded && rdev->sb_size) {
1618                 memcpy(page, page_address(rdev->sb_page), rdev->sb_size);
1619                 return rdev->sb_size;
1620         } else
1621                 return 0;
1622 }
1623 static struct rdev_sysfs_entry rdev_super = __ATTR_RO(super);
1624
1625 static ssize_t
1626 errors_show(mdk_rdev_t *rdev, char *page)
1627 {
1628         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
1629 }
1630
1631 static ssize_t
1632 errors_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1633 {
1634         char *e;
1635         unsigned long n = simple_strtoul(buf, &e, 10);
1636         if (*buf && (*e == 0 || *e == '\n')) {
1637                 atomic_set(&rdev->corrected_errors, n);
1638                 return len;
1639         }
1640         return -EINVAL;
1641 }
1642 static struct rdev_sysfs_entry rdev_errors =
1643 __ATTR(errors, 0644, errors_show, errors_store);
1644
1645 static ssize_t
1646 slot_show(mdk_rdev_t *rdev, char *page)
1647 {
1648         if (rdev->raid_disk < 0)
1649                 return sprintf(page, "none\n");
1650         else
1651                 return sprintf(page, "%d\n", rdev->raid_disk);
1652 }
1653
1654 static ssize_t
1655 slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1656 {
1657         char *e;
1658         int slot = simple_strtoul(buf, &e, 10);
1659         if (strncmp(buf, "none", 4)==0)
1660                 slot = -1;
1661         else if (e==buf || (*e && *e!= '\n'))
1662                 return -EINVAL;
1663         if (rdev->mddev->pers)
1664                 /* Cannot set slot in active array (yet) */
1665                 return -EBUSY;
1666         if (slot >= rdev->mddev->raid_disks)
1667                 return -ENOSPC;
1668         rdev->raid_disk = slot;
1669         /* assume it is working */
1670         rdev->flags = 0;
1671         set_bit(In_sync, &rdev->flags);
1672         return len;
1673 }
1674
1675
1676 static struct rdev_sysfs_entry rdev_slot =
1677 __ATTR(slot, 0644, slot_show, slot_store);
1678
1679 static ssize_t
1680 offset_show(mdk_rdev_t *rdev, char *page)
1681 {
1682         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
1683 }
1684
1685 static ssize_t
1686 offset_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1687 {
1688         char *e;
1689         unsigned long long offset = simple_strtoull(buf, &e, 10);
1690         if (e==buf || (*e && *e != '\n'))
1691                 return -EINVAL;
1692         if (rdev->mddev->pers)
1693                 return -EBUSY;
1694         rdev->data_offset = offset;
1695         return len;
1696 }
1697
1698 static struct rdev_sysfs_entry rdev_offset =
1699 __ATTR(offset, 0644, offset_show, offset_store);
1700
1701 static ssize_t
1702 rdev_size_show(mdk_rdev_t *rdev, char *page)
1703 {
1704         return sprintf(page, "%llu\n", (unsigned long long)rdev->size);
1705 }
1706
1707 static ssize_t
1708 rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
1709 {
1710         char *e;
1711         unsigned long long size = simple_strtoull(buf, &e, 10);
1712         if (e==buf || (*e && *e != '\n'))
1713                 return -EINVAL;
1714         if (rdev->mddev->pers)
1715                 return -EBUSY;
1716         rdev->size = size;
1717         if (size < rdev->mddev->size || rdev->mddev->size == 0)
1718                 rdev->mddev->size = size;
1719         return len;
1720 }
1721
1722 static struct rdev_sysfs_entry rdev_size =
1723 __ATTR(size, 0644, rdev_size_show, rdev_size_store);
1724
1725 static struct attribute *rdev_default_attrs[] = {
1726         &rdev_state.attr,
1727         &rdev_super.attr,
1728         &rdev_errors.attr,
1729         &rdev_slot.attr,
1730         &rdev_offset.attr,
1731         &rdev_size.attr,
1732         NULL,
1733 };
1734 static ssize_t
1735 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
1736 {
1737         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
1738         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
1739
1740         if (!entry->show)
1741                 return -EIO;
1742         return entry->show(rdev, page);
1743 }
1744
1745 static ssize_t
1746 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
1747               const char *page, size_t length)
1748 {
1749         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
1750         mdk_rdev_t *rdev = container_of(kobj, mdk_rdev_t, kobj);
1751
1752         if (!entry->store)
1753                 return -EIO;
1754         return entry->store(rdev, page, length);
1755 }
1756
1757 static void rdev_free(struct kobject *ko)
1758 {
1759         mdk_rdev_t *rdev = container_of(ko, mdk_rdev_t, kobj);
1760         kfree(rdev);
1761 }
1762 static struct sysfs_ops rdev_sysfs_ops = {
1763         .show           = rdev_attr_show,
1764         .store          = rdev_attr_store,
1765 };
1766 static struct kobj_type rdev_ktype = {
1767         .release        = rdev_free,
1768         .sysfs_ops      = &rdev_sysfs_ops,
1769         .default_attrs  = rdev_default_attrs,
1770 };
1771
1772 /*
1773  * Import a device. If 'super_format' >= 0, then sanity check the superblock
1774  *
1775  * mark the device faulty if:
1776  *
1777  *   - the device is nonexistent (zero size)
1778  *   - the device has no valid superblock
1779  *
1780  * a faulty rdev _never_ has rdev->sb set.
1781  */
1782 static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
1783 {
1784         char b[BDEVNAME_SIZE];
1785         int err;
1786         mdk_rdev_t *rdev;
1787         sector_t size;
1788
1789         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
1790         if (!rdev) {
1791                 printk(KERN_ERR "md: could not alloc mem for new device!\n");
1792                 return ERR_PTR(-ENOMEM);
1793         }
1794
1795         if ((err = alloc_disk_sb(rdev)))
1796                 goto abort_free;
1797
1798         err = lock_rdev(rdev, newdev);
1799         if (err)
1800                 goto abort_free;
1801
1802         rdev->kobj.parent = NULL;
1803         rdev->kobj.ktype = &rdev_ktype;
1804         kobject_init(&rdev->kobj);
1805
1806         rdev->desc_nr = -1;
1807         rdev->flags = 0;
1808         rdev->data_offset = 0;
1809         atomic_set(&rdev->nr_pending, 0);
1810         atomic_set(&rdev->read_errors, 0);
1811         atomic_set(&rdev->corrected_errors, 0);
1812
1813         size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
1814         if (!size) {
1815                 printk(KERN_WARNING 
1816                         "md: %s has zero or unknown size, marking faulty!\n",
1817                         bdevname(rdev->bdev,b));
1818                 err = -EINVAL;
1819                 goto abort_free;
1820         }
1821
1822         if (super_format >= 0) {
1823                 err = super_types[super_format].
1824                         load_super(rdev, NULL, super_minor);
1825                 if (err == -EINVAL) {
1826                         printk(KERN_WARNING 
1827                                 "md: %s has invalid sb, not importing!\n",
1828                                 bdevname(rdev->bdev,b));
1829                         goto abort_free;
1830                 }
1831                 if (err < 0) {
1832                         printk(KERN_WARNING 
1833                                 "md: could not read %s's sb, not importing!\n",
1834                                 bdevname(rdev->bdev,b));
1835                         goto abort_free;
1836                 }
1837         }
1838         INIT_LIST_HEAD(&rdev->same_set);
1839
1840         return rdev;
1841
1842 abort_free:
1843         if (rdev->sb_page) {
1844                 if (rdev->bdev)
1845                         unlock_rdev(rdev);
1846                 free_disk_sb(rdev);
1847         }
1848         kfree(rdev);
1849         return ERR_PTR(err);
1850 }
1851
1852 /*
1853  * Check a full RAID array for plausibility
1854  */
1855
1856
1857 static void analyze_sbs(mddev_t * mddev)
1858 {
1859         int i;
1860         struct list_head *tmp;
1861         mdk_rdev_t *rdev, *freshest;
1862         char b[BDEVNAME_SIZE];
1863
1864         freshest = NULL;
1865         ITERATE_RDEV(mddev,rdev,tmp)
1866                 switch (super_types[mddev->major_version].
1867                         load_super(rdev, freshest, mddev->minor_version)) {
1868                 case 1:
1869                         freshest = rdev;
1870                         break;
1871                 case 0:
1872                         break;
1873                 default:
1874                         printk( KERN_ERR \
1875                                 "md: fatal superblock inconsistency in %s"
1876                                 " -- removing from array\n", 
1877                                 bdevname(rdev->bdev,b));
1878                         kick_rdev_from_array(rdev);
1879                 }
1880
1881
1882         super_types[mddev->major_version].
1883                 validate_super(mddev, freshest);
1884
1885         i = 0;
1886         ITERATE_RDEV(mddev,rdev,tmp) {
1887                 if (rdev != freshest)
1888                         if (super_types[mddev->major_version].
1889                             validate_super(mddev, rdev)) {
1890                                 printk(KERN_WARNING "md: kicking non-fresh %s"
1891                                         " from array!\n",
1892                                         bdevname(rdev->bdev,b));
1893                                 kick_rdev_from_array(rdev);
1894                                 continue;
1895                         }
1896                 if (mddev->level == LEVEL_MULTIPATH) {
1897                         rdev->desc_nr = i++;
1898                         rdev->raid_disk = rdev->desc_nr;
1899                         set_bit(In_sync, &rdev->flags);
1900                 }
1901         }
1902
1903
1904
1905         if (mddev->recovery_cp != MaxSector &&
1906             mddev->level >= 1)
1907                 printk(KERN_ERR "md: %s: raid array is not clean"
1908                        " -- starting background reconstruction\n",
1909                        mdname(mddev));
1910
1911 }
1912
1913 static ssize_t
1914 level_show(mddev_t *mddev, char *page)
1915 {
1916         struct mdk_personality *p = mddev->pers;
1917         if (p)
1918                 return sprintf(page, "%s\n", p->name);
1919         else if (mddev->clevel[0])
1920                 return sprintf(page, "%s\n", mddev->clevel);
1921         else if (mddev->level != LEVEL_NONE)
1922                 return sprintf(page, "%d\n", mddev->level);
1923         else
1924                 return 0;
1925 }
1926
1927 static ssize_t
1928 level_store(mddev_t *mddev, const char *buf, size_t len)
1929 {
1930         int rv = len;
1931         if (mddev->pers)
1932                 return -EBUSY;
1933         if (len == 0)
1934                 return 0;
1935         if (len >= sizeof(mddev->clevel))
1936                 return -ENOSPC;
1937         strncpy(mddev->clevel, buf, len);
1938         if (mddev->clevel[len-1] == '\n')
1939                 len--;
1940         mddev->clevel[len] = 0;
1941         mddev->level = LEVEL_NONE;
1942         return rv;
1943 }
1944
1945 static struct md_sysfs_entry md_level =
1946 __ATTR(level, 0644, level_show, level_store);
1947
1948 static ssize_t
1949 raid_disks_show(mddev_t *mddev, char *page)
1950 {
1951         if (mddev->raid_disks == 0)
1952                 return 0;
1953         return sprintf(page, "%d\n", mddev->raid_disks);
1954 }
1955
1956 static int update_raid_disks(mddev_t *mddev, int raid_disks);
1957
1958 static ssize_t
1959 raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
1960 {
1961         /* can only set raid_disks if array is not yet active */
1962         char *e;
1963         int rv = 0;
1964         unsigned long n = simple_strtoul(buf, &e, 10);
1965
1966         if (!*buf || (*e && *e != '\n'))
1967                 return -EINVAL;
1968
1969         if (mddev->pers)
1970                 rv = update_raid_disks(mddev, n);
1971         else
1972                 mddev->raid_disks = n;
1973         return rv ? rv : len;
1974 }
1975 static struct md_sysfs_entry md_raid_disks =
1976 __ATTR(raid_disks, 0644, raid_disks_show, raid_disks_store);
1977
1978 static ssize_t
1979 chunk_size_show(mddev_t *mddev, char *page)
1980 {
1981         return sprintf(page, "%d\n", mddev->chunk_size);
1982 }
1983
1984 static ssize_t
1985 chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
1986 {
1987         /* can only set chunk_size if array is not yet active */
1988         char *e;
1989         unsigned long n = simple_strtoul(buf, &e, 10);
1990
1991         if (mddev->pers)
1992                 return -EBUSY;
1993         if (!*buf || (*e && *e != '\n'))
1994                 return -EINVAL;
1995
1996         mddev->chunk_size = n;
1997         return len;
1998 }
1999 static struct md_sysfs_entry md_chunk_size =
2000 __ATTR(chunk_size, 0644, chunk_size_show, chunk_size_store);
2001
2002 static ssize_t
2003 null_show(mddev_t *mddev, char *page)
2004 {
2005         return -EINVAL;
2006 }
2007
2008 static ssize_t
2009 new_dev_store(mddev_t *mddev, const char *buf, size_t len)
2010 {
2011         /* buf must be %d:%d\n? giving major and minor numbers */
2012         /* The new device is added to the array.
2013          * If the array has a persistent superblock, we read the
2014          * superblock to initialise info and check validity.
2015          * Otherwise, only checking done is that in bind_rdev_to_array,
2016          * which mainly checks size.
2017          */
2018         char *e;
2019         int major = simple_strtoul(buf, &e, 10);
2020         int minor;
2021         dev_t dev;
2022         mdk_rdev_t *rdev;
2023         int err;
2024
2025         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
2026                 return -EINVAL;
2027         minor = simple_strtoul(e+1, &e, 10);
2028         if (*e && *e != '\n')
2029                 return -EINVAL;
2030         dev = MKDEV(major, minor);
2031         if (major != MAJOR(dev) ||
2032             minor != MINOR(dev))
2033                 return -EOVERFLOW;
2034
2035
2036         if (mddev->persistent) {
2037                 rdev = md_import_device(dev, mddev->major_version,
2038                                         mddev->minor_version);
2039                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
2040                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
2041                                                        mdk_rdev_t, same_set);
2042                         err = super_types[mddev->major_version]
2043                                 .load_super(rdev, rdev0, mddev->minor_version);
2044                         if (err < 0)
2045                                 goto out;
2046                 }
2047         } else
2048                 rdev = md_import_device(dev, -1, -1);
2049
2050         if (IS_ERR(rdev))
2051                 return PTR_ERR(rdev);
2052         err = bind_rdev_to_array(rdev, mddev);
2053  out:
2054         if (err)
2055                 export_rdev(rdev);
2056         return err ? err : len;
2057 }
2058
2059 static struct md_sysfs_entry md_new_device =
2060 __ATTR(new_dev, 0200, null_show, new_dev_store);
2061
2062 static ssize_t
2063 size_show(mddev_t *mddev, char *page)
2064 {
2065         return sprintf(page, "%llu\n", (unsigned long long)mddev->size);
2066 }
2067
2068 static int update_size(mddev_t *mddev, unsigned long size);
2069
2070 static ssize_t
2071 size_store(mddev_t *mddev, const char *buf, size_t len)
2072 {
2073         /* If array is inactive, we can reduce the component size, but
2074          * not increase it (except from 0).
2075          * If array is active, we can try an on-line resize
2076          */
2077         char *e;
2078         int err = 0;
2079         unsigned long long size = simple_strtoull(buf, &e, 10);
2080         if (!*buf || *buf == '\n' ||
2081             (*e && *e != '\n'))
2082                 return -EINVAL;
2083
2084         if (mddev->pers) {
2085                 err = update_size(mddev, size);
2086                 md_update_sb(mddev);
2087         } else {
2088                 if (mddev->size == 0 ||
2089                     mddev->size > size)
2090                         mddev->size = size;
2091                 else
2092                         err = -ENOSPC;
2093         }
2094         return err ? err : len;
2095 }
2096
2097 static struct md_sysfs_entry md_size =
2098 __ATTR(component_size, 0644, size_show, size_store);
2099
2100
2101 /* Metdata version.
2102  * This is either 'none' for arrays with externally managed metadata,
2103  * or N.M for internally known formats
2104  */
2105 static ssize_t
2106 metadata_show(mddev_t *mddev, char *page)
2107 {
2108         if (mddev->persistent)
2109                 return sprintf(page, "%d.%d\n",
2110                                mddev->major_version, mddev->minor_version);
2111         else
2112                 return sprintf(page, "none\n");
2113 }
2114
2115 static ssize_t
2116 metadata_store(mddev_t *mddev, const char *buf, size_t len)
2117 {
2118         int major, minor;
2119         char *e;
2120         if (!list_empty(&mddev->disks))
2121                 return -EBUSY;
2122
2123         if (cmd_match(buf, "none")) {
2124                 mddev->persistent = 0;
2125                 mddev->major_version = 0;
2126                 mddev->minor_version = 90;
2127                 return len;
2128         }
2129         major = simple_strtoul(buf, &e, 10);
2130         if (e==buf || *e != '.')
2131                 return -EINVAL;
2132         buf = e+1;
2133         minor = simple_strtoul(buf, &e, 10);
2134         if (e==buf || *e != '\n')
2135                 return -EINVAL;
2136         if (major >= sizeof(super_types)/sizeof(super_types[0]) ||
2137             super_types[major].name == NULL)
2138                 return -ENOENT;
2139         mddev->major_version = major;
2140         mddev->minor_version = minor;
2141         mddev->persistent = 1;
2142         return len;
2143 }
2144
2145 static struct md_sysfs_entry md_metadata =
2146 __ATTR(metadata_version, 0644, metadata_show, metadata_store);
2147
2148 static ssize_t
2149 action_show(mddev_t *mddev, char *page)
2150 {
2151         char *type = "idle";
2152         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2153             test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) {
2154                 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
2155                         if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2156                                 type = "resync";
2157                         else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
2158                                 type = "check";
2159                         else
2160                                 type = "repair";
2161                 } else
2162                         type = "recover";
2163         }
2164         return sprintf(page, "%s\n", type);
2165 }
2166
2167 static ssize_t
2168 action_store(mddev_t *mddev, const char *page, size_t len)
2169 {
2170         if (!mddev->pers || !mddev->pers->sync_request)
2171                 return -EINVAL;
2172
2173         if (cmd_match(page, "idle")) {
2174                 if (mddev->sync_thread) {
2175                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2176                         md_unregister_thread(mddev->sync_thread);
2177                         mddev->sync_thread = NULL;
2178                         mddev->recovery = 0;
2179                 }
2180         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
2181                    test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
2182                 return -EBUSY;
2183         else if (cmd_match(page, "resync") || cmd_match(page, "recover"))
2184                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2185         else {
2186                 if (cmd_match(page, "check"))
2187                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
2188                 else if (cmd_match(page, "repair"))
2189                         return -EINVAL;
2190                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
2191                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
2192         }
2193         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2194         md_wakeup_thread(mddev->thread);
2195         return len;
2196 }
2197
2198 static ssize_t
2199 mismatch_cnt_show(mddev_t *mddev, char *page)
2200 {
2201         return sprintf(page, "%llu\n",
2202                        (unsigned long long) mddev->resync_mismatches);
2203 }
2204
2205 static struct md_sysfs_entry
2206 md_scan_mode = __ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
2207
2208
2209 static struct md_sysfs_entry
2210 md_mismatches = __ATTR_RO(mismatch_cnt);
2211
2212 static ssize_t
2213 sync_min_show(mddev_t *mddev, char *page)
2214 {
2215         return sprintf(page, "%d (%s)\n", speed_min(mddev),
2216                        mddev->sync_speed_min ? "local": "system");
2217 }
2218
2219 static ssize_t
2220 sync_min_store(mddev_t *mddev, const char *buf, size_t len)
2221 {
2222         int min;
2223         char *e;
2224         if (strncmp(buf, "system", 6)==0) {
2225                 mddev->sync_speed_min = 0;
2226                 return len;
2227         }
2228         min = simple_strtoul(buf, &e, 10);
2229         if (buf == e || (*e && *e != '\n') || min <= 0)
2230                 return -EINVAL;
2231         mddev->sync_speed_min = min;
2232         return len;
2233 }
2234
2235 static struct md_sysfs_entry md_sync_min =
2236 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
2237
2238 static ssize_t
2239 sync_max_show(mddev_t *mddev, char *page)
2240 {
2241         return sprintf(page, "%d (%s)\n", speed_max(mddev),
2242                        mddev->sync_speed_max ? "local": "system");
2243 }
2244
2245 static ssize_t
2246 sync_max_store(mddev_t *mddev, const char *buf, size_t len)
2247 {
2248         int max;
2249         char *e;
2250         if (strncmp(buf, "system", 6)==0) {
2251                 mddev->sync_speed_max = 0;
2252                 return len;
2253         }
2254         max = simple_strtoul(buf, &e, 10);
2255         if (buf == e || (*e && *e != '\n') || max <= 0)
2256                 return -EINVAL;
2257         mddev->sync_speed_max = max;
2258         return len;
2259 }
2260
2261 static struct md_sysfs_entry md_sync_max =
2262 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
2263
2264
2265 static ssize_t
2266 sync_speed_show(mddev_t *mddev, char *page)
2267 {
2268         unsigned long resync, dt, db;
2269         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active));
2270         dt = ((jiffies - mddev->resync_mark) / HZ);
2271         if (!dt) dt++;
2272         db = resync - (mddev->resync_mark_cnt);
2273         return sprintf(page, "%ld\n", db/dt/2); /* K/sec */
2274 }
2275
2276 static struct md_sysfs_entry
2277 md_sync_speed = __ATTR_RO(sync_speed);
2278
2279 static ssize_t
2280 sync_completed_show(mddev_t *mddev, char *page)
2281 {
2282         unsigned long max_blocks, resync;
2283
2284         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
2285                 max_blocks = mddev->resync_max_sectors;
2286         else
2287                 max_blocks = mddev->size << 1;
2288
2289         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active));
2290         return sprintf(page, "%lu / %lu\n", resync, max_blocks);
2291 }
2292
2293 static struct md_sysfs_entry
2294 md_sync_completed = __ATTR_RO(sync_completed);
2295
2296 static struct attribute *md_default_attrs[] = {
2297         &md_level.attr,
2298         &md_raid_disks.attr,
2299         &md_chunk_size.attr,
2300         &md_size.attr,
2301         &md_metadata.attr,
2302         &md_new_device.attr,
2303         NULL,
2304 };
2305
2306 static struct attribute *md_redundancy_attrs[] = {
2307         &md_scan_mode.attr,
2308         &md_mismatches.attr,
2309         &md_sync_min.attr,
2310         &md_sync_max.attr,
2311         &md_sync_speed.attr,
2312         &md_sync_completed.attr,
2313         NULL,
2314 };
2315 static struct attribute_group md_redundancy_group = {
2316         .name = NULL,
2317         .attrs = md_redundancy_attrs,
2318 };
2319
2320
2321 static ssize_t
2322 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
2323 {
2324         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
2325         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
2326         ssize_t rv;
2327
2328         if (!entry->show)
2329                 return -EIO;
2330         mddev_lock(mddev);
2331         rv = entry->show(mddev, page);
2332         mddev_unlock(mddev);
2333         return rv;
2334 }
2335
2336 static ssize_t
2337 md_attr_store(struct kobject *kobj, struct attribute *attr,
2338               const char *page, size_t length)
2339 {
2340         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
2341         mddev_t *mddev = container_of(kobj, struct mddev_s, kobj);
2342         ssize_t rv;
2343
2344         if (!entry->store)
2345                 return -EIO;
2346         mddev_lock(mddev);
2347         rv = entry->store(mddev, page, length);
2348         mddev_unlock(mddev);
2349         return rv;
2350 }
2351
2352 static void md_free(struct kobject *ko)
2353 {
2354         mddev_t *mddev = container_of(ko, mddev_t, kobj);
2355         kfree(mddev);
2356 }
2357
2358 static struct sysfs_ops md_sysfs_ops = {
2359         .show   = md_attr_show,
2360         .store  = md_attr_store,
2361 };
2362 static struct kobj_type md_ktype = {
2363         .release        = md_free,
2364         .sysfs_ops      = &md_sysfs_ops,
2365         .default_attrs  = md_default_attrs,
2366 };
2367
2368 int mdp_major = 0;
2369
2370 static struct kobject *md_probe(dev_t dev, int *part, void *data)
2371 {
2372         static DECLARE_MUTEX(disks_sem);
2373         mddev_t *mddev = mddev_find(dev);
2374         struct gendisk *disk;
2375         int partitioned = (MAJOR(dev) != MD_MAJOR);
2376         int shift = partitioned ? MdpMinorShift : 0;
2377         int unit = MINOR(dev) >> shift;
2378
2379         if (!mddev)
2380                 return NULL;
2381
2382         down(&disks_sem);
2383         if (mddev->gendisk) {
2384                 up(&disks_sem);
2385                 mddev_put(mddev);
2386                 return NULL;
2387         }
2388         disk = alloc_disk(1 << shift);
2389         if (!disk) {
2390                 up(&disks_sem);
2391                 mddev_put(mddev);
2392                 return NULL;
2393         }
2394         disk->major = MAJOR(dev);
2395         disk->first_minor = unit << shift;
2396         if (partitioned) {
2397                 sprintf(disk->disk_name, "md_d%d", unit);
2398                 sprintf(disk->devfs_name, "md/d%d", unit);
2399         } else {
2400                 sprintf(disk->disk_name, "md%d", unit);
2401                 sprintf(disk->devfs_name, "md/%d", unit);
2402         }
2403         disk->fops = &md_fops;
2404         disk->private_data = mddev;
2405         disk->queue = mddev->queue;
2406         add_disk(disk);
2407         mddev->gendisk = disk;
2408         up(&disks_sem);
2409         mddev->kobj.parent = &disk->kobj;
2410         mddev->kobj.k_name = NULL;
2411         snprintf(mddev->kobj.name, KOBJ_NAME_LEN, "%s", "md");
2412         mddev->kobj.ktype = &md_ktype;
2413         kobject_register(&mddev->kobj);
2414         return NULL;
2415 }
2416
2417 void md_wakeup_thread(mdk_thread_t *thread);
2418
2419 static void md_safemode_timeout(unsigned long data)
2420 {
2421         mddev_t *mddev = (mddev_t *) data;
2422
2423         mddev->safemode = 1;
2424         md_wakeup_thread(mddev->thread);
2425 }
2426
2427 static int start_dirty_degraded;
2428
2429 static int do_md_run(mddev_t * mddev)
2430 {
2431         int err;
2432         int chunk_size;
2433         struct list_head *tmp;
2434         mdk_rdev_t *rdev;
2435         struct gendisk *disk;
2436         struct mdk_personality *pers;
2437         char b[BDEVNAME_SIZE];
2438
2439         if (list_empty(&mddev->disks))
2440                 /* cannot run an array with no devices.. */
2441                 return -EINVAL;
2442
2443         if (mddev->pers)
2444                 return -EBUSY;
2445
2446         /*
2447          * Analyze all RAID superblock(s)
2448          */
2449         if (!mddev->raid_disks)
2450                 analyze_sbs(mddev);
2451
2452         chunk_size = mddev->chunk_size;
2453
2454         if (chunk_size) {
2455                 if (chunk_size > MAX_CHUNK_SIZE) {
2456                         printk(KERN_ERR "too big chunk_size: %d > %d\n",
2457                                 chunk_size, MAX_CHUNK_SIZE);
2458                         return -EINVAL;
2459                 }
2460                 /*
2461                  * chunk-size has to be a power of 2 and multiples of PAGE_SIZE
2462                  */
2463                 if ( (1 << ffz(~chunk_size)) != chunk_size) {
2464                         printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
2465                         return -EINVAL;
2466                 }
2467                 if (chunk_size < PAGE_SIZE) {
2468                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
2469                                 chunk_size, PAGE_SIZE);
2470                         return -EINVAL;
2471                 }
2472
2473                 /* devices must have minimum size of one chunk */
2474                 ITERATE_RDEV(mddev,rdev,tmp) {
2475                         if (test_bit(Faulty, &rdev->flags))
2476                                 continue;
2477                         if (rdev->size < chunk_size / 1024) {
2478                                 printk(KERN_WARNING
2479                                         "md: Dev %s smaller than chunk_size:"
2480                                         " %lluk < %dk\n",
2481                                         bdevname(rdev->bdev,b),
2482                                         (unsigned long long)rdev->size,
2483                                         chunk_size / 1024);
2484                                 return -EINVAL;
2485                         }
2486                 }
2487         }
2488
2489 #ifdef CONFIG_KMOD
2490         if (mddev->level != LEVEL_NONE)
2491                 request_module("md-level-%d", mddev->level);
2492         else if (mddev->clevel[0])
2493                 request_module("md-%s", mddev->clevel);
2494 #endif
2495
2496         /*
2497          * Drop all container device buffers, from now on
2498          * the only valid external interface is through the md
2499          * device.
2500          * Also find largest hardsector size
2501          */
2502         ITERATE_RDEV(mddev,rdev,tmp) {
2503                 if (test_bit(Faulty, &rdev->flags))
2504                         continue;
2505                 sync_blockdev(rdev->bdev);
2506                 invalidate_bdev(rdev->bdev, 0);
2507         }
2508
2509         md_probe(mddev->unit, NULL, NULL);
2510         disk = mddev->gendisk;
2511         if (!disk)
2512                 return -ENOMEM;
2513
2514         spin_lock(&pers_lock);
2515         pers = find_pers(mddev->level, mddev->clevel);
2516         if (!pers || !try_module_get(pers->owner)) {
2517                 spin_unlock(&pers_lock);
2518                 if (mddev->level != LEVEL_NONE)
2519                         printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
2520                                mddev->level);
2521                 else
2522                         printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
2523                                mddev->clevel);
2524                 return -EINVAL;
2525         }
2526         mddev->pers = pers;
2527         spin_unlock(&pers_lock);
2528         mddev->level = pers->level;
2529         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
2530
2531         mddev->recovery = 0;
2532         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
2533         mddev->barriers_work = 1;
2534         mddev->ok_start_degraded = start_dirty_degraded;
2535
2536         if (start_readonly)
2537                 mddev->ro = 2; /* read-only, but switch on first write */
2538
2539         err = mddev->pers->run(mddev);
2540         if (!err && mddev->pers->sync_request) {
2541                 err = bitmap_create(mddev);
2542                 if (err) {
2543                         printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
2544                                mdname(mddev), err);
2545                         mddev->pers->stop(mddev);
2546                 }
2547         }
2548         if (err) {
2549                 printk(KERN_ERR "md: pers->run() failed ...\n");
2550                 module_put(mddev->pers->owner);
2551                 mddev->pers = NULL;
2552                 bitmap_destroy(mddev);
2553                 return err;
2554         }
2555         if (mddev->pers->sync_request)
2556                 sysfs_create_group(&mddev->kobj, &md_redundancy_group);
2557         else if (mddev->ro == 2) /* auto-readonly not meaningful */
2558                 mddev->ro = 0;
2559
2560         atomic_set(&mddev->writes_pending,0);
2561         mddev->safemode = 0;
2562         mddev->safemode_timer.function = md_safemode_timeout;
2563         mddev->safemode_timer.data = (unsigned long) mddev;
2564         mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
2565         mddev->in_sync = 1;
2566
2567         ITERATE_RDEV(mddev,rdev,tmp)
2568                 if (rdev->raid_disk >= 0) {
2569                         char nm[20];
2570                         sprintf(nm, "rd%d", rdev->raid_disk);
2571                         sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
2572                 }
2573         
2574         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2575         md_wakeup_thread(mddev->thread);
2576         
2577         if (mddev->sb_dirty)
2578                 md_update_sb(mddev);
2579
2580         set_capacity(disk, mddev->array_size<<1);
2581
2582         /* If we call blk_queue_make_request here, it will
2583          * re-initialise max_sectors etc which may have been
2584          * refined inside -> run.  So just set the bits we need to set.
2585          * Most initialisation happended when we called
2586          * blk_queue_make_request(..., md_fail_request)
2587          * earlier.
2588          */
2589         mddev->queue->queuedata = mddev;
2590         mddev->queue->make_request_fn = mddev->pers->make_request;
2591
2592         mddev->changed = 1;
2593         md_new_event(mddev);
2594         return 0;
2595 }
2596
2597 static int restart_array(mddev_t *mddev)
2598 {
2599         struct gendisk *disk = mddev->gendisk;
2600         int err;
2601
2602         /*
2603          * Complain if it has no devices
2604          */
2605         err = -ENXIO;
2606         if (list_empty(&mddev->disks))
2607                 goto out;
2608
2609         if (mddev->pers) {
2610                 err = -EBUSY;
2611                 if (!mddev->ro)
2612                         goto out;
2613
2614                 mddev->safemode = 0;
2615                 mddev->ro = 0;
2616                 set_disk_ro(disk, 0);
2617
2618                 printk(KERN_INFO "md: %s switched to read-write mode.\n",
2619                         mdname(mddev));
2620                 /*
2621                  * Kick recovery or resync if necessary
2622                  */
2623                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2624                 md_wakeup_thread(mddev->thread);
2625                 err = 0;
2626         } else {
2627                 printk(KERN_ERR "md: %s has no personality assigned.\n",
2628                         mdname(mddev));
2629                 err = -EINVAL;
2630         }
2631
2632 out:
2633         return err;
2634 }
2635
2636 static int do_md_stop(mddev_t * mddev, int ro)
2637 {
2638         int err = 0;
2639         struct gendisk *disk = mddev->gendisk;
2640
2641         if (mddev->pers) {
2642                 if (atomic_read(&mddev->active)>2) {
2643                         printk("md: %s still in use.\n",mdname(mddev));
2644                         return -EBUSY;
2645                 }
2646
2647                 if (mddev->sync_thread) {
2648                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2649                         md_unregister_thread(mddev->sync_thread);
2650                         mddev->sync_thread = NULL;
2651                 }
2652
2653                 del_timer_sync(&mddev->safemode_timer);
2654
2655                 invalidate_partition(disk, 0);
2656
2657                 if (ro) {
2658                         err  = -ENXIO;
2659                         if (mddev->ro==1)
2660                                 goto out;
2661                         mddev->ro = 1;
2662                 } else {
2663                         bitmap_flush(mddev);
2664                         md_super_wait(mddev);
2665                         if (mddev->ro)
2666                                 set_disk_ro(disk, 0);
2667                         blk_queue_make_request(mddev->queue, md_fail_request);
2668                         mddev->pers->stop(mddev);
2669                         if (mddev->pers->sync_request)
2670                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
2671
2672                         module_put(mddev->pers->owner);
2673                         mddev->pers = NULL;
2674                         if (mddev->ro)
2675                                 mddev->ro = 0;
2676                 }
2677                 if (!mddev->in_sync) {
2678                         /* mark array as shutdown cleanly */
2679                         mddev->in_sync = 1;
2680                         md_update_sb(mddev);
2681                 }
2682                 if (ro)
2683                         set_disk_ro(disk, 1);
2684         }
2685
2686         bitmap_destroy(mddev);
2687         if (mddev->bitmap_file) {
2688                 atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
2689                 fput(mddev->bitmap_file);
2690                 mddev->bitmap_file = NULL;
2691         }
2692         mddev->bitmap_offset = 0;
2693
2694         /*
2695          * Free resources if final stop
2696          */
2697         if (!ro) {
2698                 mdk_rdev_t *rdev;
2699                 struct list_head *tmp;
2700                 struct gendisk *disk;
2701                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
2702
2703                 ITERATE_RDEV(mddev,rdev,tmp)
2704                         if (rdev->raid_disk >= 0) {
2705                                 char nm[20];
2706                                 sprintf(nm, "rd%d", rdev->raid_disk);
2707                                 sysfs_remove_link(&mddev->kobj, nm);
2708                         }
2709
2710                 export_array(mddev);
2711
2712                 mddev->array_size = 0;
2713                 disk = mddev->gendisk;
2714                 if (disk)
2715                         set_capacity(disk, 0);
2716                 mddev->changed = 1;
2717         } else
2718                 printk(KERN_INFO "md: %s switched to read-only mode.\n",
2719                         mdname(mddev));
2720         err = 0;
2721         md_new_event(mddev);
2722 out:
2723         return err;
2724 }
2725
2726 static void autorun_array(mddev_t *mddev)
2727 {
2728         mdk_rdev_t *rdev;
2729         struct list_head *tmp;
2730         int err;
2731
2732         if (list_empty(&mddev->disks))
2733                 return;
2734
2735         printk(KERN_INFO "md: running: ");
2736
2737         ITERATE_RDEV(mddev,rdev,tmp) {
2738                 char b[BDEVNAME_SIZE];
2739                 printk("<%s>", bdevname(rdev->bdev,b));
2740         }
2741         printk("\n");
2742
2743         err = do_md_run (mddev);
2744         if (err) {
2745                 printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
2746                 do_md_stop (mddev, 0);
2747         }
2748 }
2749
2750 /*
2751  * lets try to run arrays based on all disks that have arrived
2752  * until now. (those are in pending_raid_disks)
2753  *
2754  * the method: pick the first pending disk, collect all disks with
2755  * the same UUID, remove all from the pending list and put them into
2756  * the 'same_array' list. Then order this list based on superblock
2757  * update time (freshest comes first), kick out 'old' disks and
2758  * compare superblocks. If everything's fine then run it.
2759  *
2760  * If "unit" is allocated, then bump its reference count
2761  */
2762 static void autorun_devices(int part)
2763 {
2764         struct list_head candidates;
2765         struct list_head *tmp;
2766         mdk_rdev_t *rdev0, *rdev;
2767         mddev_t *mddev;
2768         char b[BDEVNAME_SIZE];
2769
2770         printk(KERN_INFO "md: autorun ...\n");
2771         while (!list_empty(&pending_raid_disks)) {
2772                 dev_t dev;
2773                 rdev0 = list_entry(pending_raid_disks.next,
2774                                          mdk_rdev_t, same_set);
2775
2776                 printk(KERN_INFO "md: considering %s ...\n",
2777                         bdevname(rdev0->bdev,b));
2778                 INIT_LIST_HEAD(&candidates);
2779                 ITERATE_RDEV_PENDING(rdev,tmp)
2780                         if (super_90_load(rdev, rdev0, 0) >= 0) {
2781                                 printk(KERN_INFO "md:  adding %s ...\n",
2782                                         bdevname(rdev->bdev,b));
2783                                 list_move(&rdev->same_set, &candidates);
2784                         }
2785                 /*
2786                  * now we have a set of devices, with all of them having
2787                  * mostly sane superblocks. It's time to allocate the
2788                  * mddev.
2789                  */
2790                 if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
2791                         printk(KERN_INFO "md: unit number in %s is bad: %d\n",
2792                                bdevname(rdev0->bdev, b), rdev0->preferred_minor);
2793                         break;
2794                 }
2795                 if (part)
2796                         dev = MKDEV(mdp_major,
2797                                     rdev0->preferred_minor << MdpMinorShift);
2798                 else
2799                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
2800
2801                 md_probe(dev, NULL, NULL);
2802                 mddev = mddev_find(dev);
2803                 if (!mddev) {
2804                         printk(KERN_ERR 
2805                                 "md: cannot allocate memory for md drive.\n");
2806                         break;
2807                 }
2808                 if (mddev_lock(mddev)) 
2809                         printk(KERN_WARNING "md: %s locked, cannot run\n",
2810                                mdname(mddev));
2811                 else if (mddev->raid_disks || mddev->major_version
2812                          || !list_empty(&mddev->disks)) {
2813                         printk(KERN_WARNING 
2814                                 "md: %s already running, cannot run %s\n",
2815                                 mdname(mddev), bdevname(rdev0->bdev,b));
2816                         mddev_unlock(mddev);
2817                 } else {
2818                         printk(KERN_INFO "md: created %s\n", mdname(mddev));
2819                         ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
2820                                 list_del_init(&rdev->same_set);
2821                                 if (bind_rdev_to_array(rdev, mddev))
2822                                         export_rdev(rdev);
2823                         }
2824                         autorun_array(mddev);
2825                         mddev_unlock(mddev);
2826                 }
2827                 /* on success, candidates will be empty, on error
2828                  * it won't...
2829                  */
2830                 ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
2831                         export_rdev(rdev);
2832                 mddev_put(mddev);
2833         }
2834         printk(KERN_INFO "md: ... autorun DONE.\n");
2835 }
2836
2837 /*
2838  * import RAID devices based on one partition
2839  * if possible, the array gets run as well.
2840  */
2841
2842 static int autostart_array(dev_t startdev)
2843 {
2844         char b[BDEVNAME_SIZE];
2845         int err = -EINVAL, i;
2846         mdp_super_t *sb = NULL;
2847         mdk_rdev_t *start_rdev = NULL, *rdev;
2848
2849         start_rdev = md_import_device(startdev, 0, 0);
2850         if (IS_ERR(start_rdev))
2851                 return err;
2852
2853
2854         /* NOTE: this can only work for 0.90.0 superblocks */
2855         sb = (mdp_super_t*)page_address(start_rdev->sb_page);
2856         if (sb->major_version != 0 ||
2857             sb->minor_version != 90 ) {
2858                 printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
2859                 export_rdev(start_rdev);
2860                 return err;
2861         }
2862
2863         if (test_bit(Faulty, &start_rdev->flags)) {
2864                 printk(KERN_WARNING 
2865                         "md: can not autostart based on faulty %s!\n",
2866                         bdevname(start_rdev->bdev,b));
2867                 export_rdev(start_rdev);
2868                 return err;
2869         }
2870         list_add(&start_rdev->same_set, &pending_raid_disks);
2871
2872         for (i = 0; i < MD_SB_DISKS; i++) {
2873                 mdp_disk_t *desc = sb->disks + i;
2874                 dev_t dev = MKDEV(desc->major, desc->minor);
2875
2876                 if (!dev)
2877                         continue;
2878                 if (dev == startdev)
2879                         continue;
2880                 if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
2881                         continue;
2882                 rdev = md_import_device(dev, 0, 0);
2883                 if (IS_ERR(rdev))
2884                         continue;
2885
2886                 list_add(&rdev->same_set, &pending_raid_disks);
2887         }
2888
2889         /*
2890          * possibly return codes
2891          */
2892         autorun_devices(0);
2893         return 0;
2894
2895 }
2896
2897
2898 static int get_version(void __user * arg)
2899 {
2900         mdu_version_t ver;
2901
2902         ver.major = MD_MAJOR_VERSION;
2903         ver.minor = MD_MINOR_VERSION;
2904         ver.patchlevel = MD_PATCHLEVEL_VERSION;
2905
2906         if (copy_to_user(arg, &ver, sizeof(ver)))
2907                 return -EFAULT;
2908
2909         return 0;
2910 }
2911
2912 static int get_array_info(mddev_t * mddev, void __user * arg)
2913 {
2914         mdu_array_info_t info;
2915         int nr,working,active,failed,spare;
2916         mdk_rdev_t *rdev;
2917         struct list_head *tmp;
2918
2919         nr=working=active=failed=spare=0;
2920         ITERATE_RDEV(mddev,rdev,tmp) {
2921                 nr++;
2922                 if (test_bit(Faulty, &rdev->flags))
2923                         failed++;
2924                 else {
2925                         working++;
2926                         if (test_bit(In_sync, &rdev->flags))
2927                                 active++;       
2928                         else
2929                                 spare++;
2930                 }
2931         }
2932
2933         info.major_version = mddev->major_version;
2934         info.minor_version = mddev->minor_version;
2935         info.patch_version = MD_PATCHLEVEL_VERSION;
2936         info.ctime         = mddev->ctime;
2937         info.level         = mddev->level;
2938         info.size          = mddev->size;
2939         info.nr_disks      = nr;
2940         info.raid_disks    = mddev->raid_disks;
2941         info.md_minor      = mddev->md_minor;
2942         info.not_persistent= !mddev->persistent;
2943
2944         info.utime         = mddev->utime;
2945         info.state         = 0;
2946         if (mddev->in_sync)
2947                 info.state = (1<<MD_SB_CLEAN);
2948         if (mddev->bitmap && mddev->bitmap_offset)
2949                 info.state = (1<<MD_SB_BITMAP_PRESENT);
2950         info.active_disks  = active;
2951         info.working_disks = working;
2952         info.failed_disks  = failed;
2953         info.spare_disks   = spare;
2954
2955         info.layout        = mddev->layout;
2956         info.chunk_size    = mddev->chunk_size;
2957
2958         if (copy_to_user(arg, &info, sizeof(info)))
2959                 return -EFAULT;
2960
2961         return 0;
2962 }
2963
2964 static int get_bitmap_file(mddev_t * mddev, void __user * arg)
2965 {
2966         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
2967         char *ptr, *buf = NULL;
2968         int err = -ENOMEM;
2969
2970         file = kmalloc(sizeof(*file), GFP_KERNEL);
2971         if (!file)
2972                 goto out;
2973
2974         /* bitmap disabled, zero the first byte and copy out */
2975         if (!mddev->bitmap || !mddev->bitmap->file) {
2976                 file->pathname[0] = '\0';
2977                 goto copy_out;
2978         }
2979
2980         buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
2981         if (!buf)
2982                 goto out;
2983
2984         ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
2985         if (!ptr)
2986                 goto out;
2987
2988         strcpy(file->pathname, ptr);
2989
2990 copy_out:
2991         err = 0;
2992         if (copy_to_user(arg, file, sizeof(*file)))
2993                 err = -EFAULT;
2994 out:
2995         kfree(buf);
2996         kfree(file);
2997         return err;
2998 }
2999
3000 static int get_disk_info(mddev_t * mddev, void __user * arg)
3001 {
3002         mdu_disk_info_t info;
3003         unsigned int nr;
3004         mdk_rdev_t *rdev;
3005
3006         if (copy_from_user(&info, arg, sizeof(info)))
3007                 return -EFAULT;
3008
3009         nr = info.number;
3010
3011         rdev = find_rdev_nr(mddev, nr);
3012         if (rdev) {
3013                 info.major = MAJOR(rdev->bdev->bd_dev);
3014                 info.minor = MINOR(rdev->bdev->bd_dev);
3015                 info.raid_disk = rdev->raid_disk;
3016                 info.state = 0;
3017                 if (test_bit(Faulty, &rdev->flags))
3018                         info.state |= (1<<MD_DISK_FAULTY);
3019                 else if (test_bit(In_sync, &rdev->flags)) {
3020                         info.state |= (1<<MD_DISK_ACTIVE);
3021                         info.state |= (1<<MD_DISK_SYNC);
3022                 }
3023                 if (test_bit(WriteMostly, &rdev->flags))
3024                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
3025         } else {
3026                 info.major = info.minor = 0;
3027                 info.raid_disk = -1;
3028                 info.state = (1<<MD_DISK_REMOVED);
3029         }
3030
3031         if (copy_to_user(arg, &info, sizeof(info)))
3032                 return -EFAULT;
3033
3034         return 0;
3035 }
3036
3037 static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
3038 {
3039         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
3040         mdk_rdev_t *rdev;
3041         dev_t dev = MKDEV(info->major,info->minor);
3042
3043         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
3044                 return -EOVERFLOW;
3045
3046         if (!mddev->raid_disks) {
3047                 int err;
3048                 /* expecting a device which has a superblock */
3049                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
3050                 if (IS_ERR(rdev)) {
3051                         printk(KERN_WARNING 
3052                                 "md: md_import_device returned %ld\n",
3053                                 PTR_ERR(rdev));
3054                         return PTR_ERR(rdev);
3055                 }
3056                 if (!list_empty(&mddev->disks)) {
3057                         mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
3058                                                         mdk_rdev_t, same_set);
3059                         int err = super_types[mddev->major_version]
3060                                 .load_super(rdev, rdev0, mddev->minor_version);
3061                         if (err < 0) {
3062                                 printk(KERN_WARNING 
3063                                         "md: %s has different UUID to %s\n",
3064                                         bdevname(rdev->bdev,b), 
3065                                         bdevname(rdev0->bdev,b2));
3066                                 export_rdev(rdev);
3067                                 return -EINVAL;
3068                         }
3069                 }
3070                 err = bind_rdev_to_array(rdev, mddev);
3071                 if (err)
3072                         export_rdev(rdev);
3073                 return err;
3074         }
3075
3076         /*
3077          * add_new_disk can be used once the array is assembled
3078          * to add "hot spares".  They must already have a superblock
3079          * written
3080          */
3081         if (mddev->pers) {
3082                 int err;
3083                 if (!mddev->pers->hot_add_disk) {
3084                         printk(KERN_WARNING 
3085                                 "%s: personality does not support diskops!\n",
3086                                mdname(mddev));
3087                         return -EINVAL;
3088                 }
3089                 if (mddev->persistent)
3090                         rdev = md_import_device(dev, mddev->major_version,
3091                                                 mddev->minor_version);
3092                 else
3093                         rdev = md_import_device(dev, -1, -1);
3094                 if (IS_ERR(rdev)) {
3095                         printk(KERN_WARNING 
3096                                 "md: md_import_device returned %ld\n",
3097                                 PTR_ERR(rdev));
3098                         return PTR_ERR(rdev);
3099                 }
3100                 /* set save_raid_disk if appropriate */
3101                 if (!mddev->persistent) {
3102                         if (info->state & (1<<MD_DISK_SYNC)  &&
3103                             info->raid_disk < mddev->raid_disks)
3104                                 rdev->raid_disk = info->raid_disk;
3105                         else
3106                                 rdev->raid_disk = -1;
3107                 } else
3108                         super_types[mddev->major_version].
3109                                 validate_super(mddev, rdev);
3110                 rdev->saved_raid_disk = rdev->raid_disk;
3111
3112                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
3113                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
3114                         set_bit(WriteMostly, &rdev->flags);
3115
3116                 rdev->raid_disk = -1;
3117                 err = bind_rdev_to_array(rdev, mddev);
3118                 if (err)
3119                         export_rdev(rdev);
3120
3121                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3122                 md_wakeup_thread(mddev->thread);
3123                 return err;
3124         }
3125
3126         /* otherwise, add_new_disk is only allowed
3127          * for major_version==0 superblocks
3128          */
3129         if (mddev->major_version != 0) {
3130                 printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
3131                        mdname(mddev));
3132                 return -EINVAL;
3133         }
3134
3135         if (!(info->state & (1<<MD_DISK_FAULTY))) {
3136                 int err;
3137                 rdev = md_import_device (dev, -1, 0);
3138                 if (IS_ERR(rdev)) {
3139                         printk(KERN_WARNING 
3140                                 "md: error, md_import_device() returned %ld\n",
3141                                 PTR_ERR(rdev));
3142                         return PTR_ERR(rdev);
3143                 }
3144                 rdev->desc_nr = info->number;
3145                 if (info->raid_disk < mddev->raid_disks)
3146                         rdev->raid_disk = info->raid_disk;
3147                 else
3148                         rdev->raid_disk = -1;
3149
3150                 rdev->flags = 0;
3151
3152                 if (rdev->raid_disk < mddev->raid_disks)
3153                         if (info->state & (1<<MD_DISK_SYNC))
3154                                 set_bit(In_sync, &rdev->flags);
3155
3156                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
3157                         set_bit(WriteMostly, &rdev->flags);
3158
3159                 if (!mddev->persistent) {
3160                         printk(KERN_INFO "md: nonpersistent superblock ...\n");
3161                         rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
3162                 } else 
3163                         rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
3164                 rdev->size = calc_dev_size(rdev, mddev->chunk_size);
3165
3166                 err = bind_rdev_to_array(rdev, mddev);
3167                 if (err) {
3168                         export_rdev(rdev);
3169                         return err;
3170                 }
3171         }
3172
3173         return 0;
3174 }
3175
3176 static int hot_remove_disk(mddev_t * mddev, dev_t dev)
3177 {
3178         char b[BDEVNAME_SIZE];
3179         mdk_rdev_t *rdev;
3180
3181         if (!mddev->pers)
3182                 return -ENODEV;
3183
3184         rdev = find_rdev(mddev, dev);
3185         if (!rdev)
3186                 return -ENXIO;
3187
3188         if (rdev->raid_disk >= 0)
3189                 goto busy;
3190
3191         kick_rdev_from_array(rdev);
3192         md_update_sb(mddev);
3193         md_new_event(mddev);
3194
3195         return 0;
3196 busy:
3197         printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
3198                 bdevname(rdev->bdev,b), mdname(mddev));
3199         return -EBUSY;
3200 }
3201
3202 static int hot_add_disk(mddev_t * mddev, dev_t dev)
3203 {
3204         char b[BDEVNAME_SIZE];
3205         int err;
3206         unsigned int size;
3207         mdk_rdev_t *rdev;
3208
3209         if (!mddev->pers)
3210                 return -ENODEV;
3211
3212         if (mddev->major_version != 0) {
3213                 printk(KERN_WARNING "%s: HOT_ADD may only be used with"
3214                         " version-0 superblocks.\n",
3215                         mdname(mddev));
3216                 return -EINVAL;
3217         }
3218         if (!mddev->pers->hot_add_disk) {
3219                 printk(KERN_WARNING 
3220                         "%s: personality does not support diskops!\n",
3221                         mdname(mddev));
3222                 return -EINVAL;
3223         }
3224
3225         rdev = md_import_device (dev, -1, 0);
3226         if (IS_ERR(rdev)) {
3227                 printk(KERN_WARNING 
3228                         "md: error, md_import_device() returned %ld\n",
3229                         PTR_ERR(rdev));
3230                 return -EINVAL;
3231         }
3232
3233         if (mddev->persistent)
3234                 rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
3235         else
3236                 rdev->sb_offset =
3237                         rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
3238
3239         size = calc_dev_size(rdev, mddev->chunk_size);
3240         rdev->size = size;
3241
3242         if (test_bit(Faulty, &rdev->flags)) {
3243                 printk(KERN_WARNING 
3244                         "md: can not hot-add faulty %s disk to %s!\n",
3245                         bdevname(rdev->bdev,b), mdname(mddev));
3246                 err = -EINVAL;
3247                 goto abort_export;
3248         }
3249         clear_bit(In_sync, &rdev->flags);
3250         rdev->desc_nr = -1;
3251         err = bind_rdev_to_array(rdev, mddev);
3252         if (err)
3253                 goto abort_export;
3254
3255         /*
3256          * The rest should better be atomic, we can have disk failures
3257          * noticed in interrupt contexts ...
3258          */
3259
3260         if (rdev->desc_nr == mddev->max_disks) {
3261                 printk(KERN_WARNING "%s: can not hot-add to full array!\n",
3262                         mdname(mddev));
3263                 err = -EBUSY;
3264                 goto abort_unbind_export;
3265         }
3266
3267         rdev->raid_disk = -1;
3268
3269         md_update_sb(mddev);
3270
3271         /*
3272          * Kick recovery, maybe this spare has to be added to the
3273          * array immediately.
3274          */
3275         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3276         md_wakeup_thread(mddev->thread);
3277         md_new_event(mddev);
3278         return 0;
3279
3280 abort_unbind_export:
3281         unbind_rdev_from_array(rdev);
3282
3283 abort_export:
3284         export_rdev(rdev);
3285         return err;
3286 }
3287
3288 /* similar to deny_write_access, but accounts for our holding a reference
3289  * to the file ourselves */
3290 static int deny_bitmap_write_access(struct file * file)
3291 {
3292         struct inode *inode = file->f_mapping->host;
3293
3294         spin_lock(&inode->i_lock);
3295         if (atomic_read(&inode->i_writecount) > 1) {
3296                 spin_unlock(&inode->i_lock);
3297                 return -ETXTBSY;
3298         }
3299         atomic_set(&inode->i_writecount, -1);
3300         spin_unlock(&inode->i_lock);
3301
3302         return 0;
3303 }
3304
3305 static int set_bitmap_file(mddev_t *mddev, int fd)
3306 {
3307         int err;
3308
3309         if (mddev->pers) {
3310                 if (!mddev->pers->quiesce)
3311                         return -EBUSY;
3312                 if (mddev->recovery || mddev->sync_thread)
3313                         return -EBUSY;
3314                 /* we should be able to change the bitmap.. */
3315         }
3316
3317
3318         if (fd >= 0) {
3319                 if (mddev->bitmap)
3320                         return -EEXIST; /* cannot add when bitmap is present */
3321                 mddev->bitmap_file = fget(fd);
3322
3323                 if (mddev->bitmap_file == NULL) {
3324                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
3325                                mdname(mddev));
3326                         return -EBADF;
3327                 }
3328
3329                 err = deny_bitmap_write_access(mddev->bitmap_file);
3330                 if (err) {
3331                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
3332                                mdname(mddev));
3333                         fput(mddev->bitmap_file);
3334                         mddev->bitmap_file = NULL;
3335                         return err;
3336                 }
3337                 mddev->bitmap_offset = 0; /* file overrides offset */
3338         } else if (mddev->bitmap == NULL)
3339                 return -ENOENT; /* cannot remove what isn't there */
3340         err = 0;
3341         if (mddev->pers) {
3342                 mddev->pers->quiesce(mddev, 1);
3343                 if (fd >= 0)
3344                         err = bitmap_create(mddev);
3345                 if (fd < 0 || err)
3346                         bitmap_destroy(mddev);
3347                 mddev->pers->quiesce(mddev, 0);
3348         } else if (fd < 0) {
3349                 if (mddev->bitmap_file)
3350                         fput(mddev->bitmap_file);
3351                 mddev->bitmap_file = NULL;
3352         }
3353
3354         return err;
3355 }
3356
3357 /*
3358  * set_array_info is used two different ways
3359  * The original usage is when creating a new array.
3360  * In this usage, raid_disks is > 0 and it together with
3361  *  level, size, not_persistent,layout,chunksize determine the
3362  *  shape of the array.
3363  *  This will always create an array with a type-0.90.0 superblock.
3364  * The newer usage is when assembling an array.
3365  *  In this case raid_disks will be 0, and the major_version field is
3366  *  use to determine which style super-blocks are to be found on the devices.
3367  *  The minor and patch _version numbers are also kept incase the
3368  *  super_block handler wishes to interpret them.
3369  */
3370 static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
3371 {
3372
3373         if (info->raid_disks == 0) {
3374                 /* just setting version number for superblock loading */
3375                 if (info->major_version < 0 ||
3376                     info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
3377                     super_types[info->major_version].name == NULL) {
3378                         /* maybe try to auto-load a module? */
3379                         printk(KERN_INFO 
3380                                 "md: superblock version %d not known\n",
3381                                 info->major_version);
3382                         return -EINVAL;
3383                 }
3384                 mddev->major_version = info->major_version;
3385                 mddev->minor_version = info->minor_version;
3386                 mddev->patch_version = info->patch_version;
3387                 return 0;
3388         }
3389         mddev->major_version = MD_MAJOR_VERSION;
3390         mddev->minor_version = MD_MINOR_VERSION;
3391         mddev->patch_version = MD_PATCHLEVEL_VERSION;
3392         mddev->ctime         = get_seconds();
3393
3394         mddev->level         = info->level;
3395         mddev->size          = info->size;
3396         mddev->raid_disks    = info->raid_disks;
3397         /* don't set md_minor, it is determined by which /dev/md* was
3398          * openned
3399          */
3400         if (info->state & (1<<MD_SB_CLEAN))
3401                 mddev->recovery_cp = MaxSector;
3402         else
3403                 mddev->recovery_cp = 0;
3404         mddev->persistent    = ! info->not_persistent;
3405
3406         mddev->layout        = info->layout;
3407         mddev->chunk_size    = info->chunk_size;
3408
3409         mddev->max_disks     = MD_SB_DISKS;
3410
3411         mddev->sb_dirty      = 1;
3412
3413         mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
3414         mddev->bitmap_offset = 0;
3415
3416         /*
3417          * Generate a 128 bit UUID
3418          */
3419         get_random_bytes(mddev->uuid, 16);
3420
3421         return 0;
3422 }
3423
3424 static int update_size(mddev_t *mddev, unsigned long size)
3425 {
3426         mdk_rdev_t * rdev;
3427         int rv;
3428         struct list_head *tmp;
3429
3430         if (mddev->pers->resize == NULL)
3431                 return -EINVAL;
3432         /* The "size" is the amount of each device that is used.
3433          * This can only make sense for arrays with redundancy.
3434          * linear and raid0 always use whatever space is available
3435          * We can only consider changing the size if no resync
3436          * or reconstruction is happening, and if the new size
3437          * is acceptable. It must fit before the sb_offset or,
3438          * if that is <data_offset, it must fit before the
3439          * size of each device.
3440          * If size is zero, we find the largest size that fits.
3441          */
3442         if (mddev->sync_thread)
3443                 return -EBUSY;
3444         ITERATE_RDEV(mddev,rdev,tmp) {
3445                 sector_t avail;
3446                 int fit = (size == 0);
3447                 if (rdev->sb_offset > rdev->data_offset)
3448                         avail = (rdev->sb_offset*2) - rdev->data_offset;
3449                 else
3450                         avail = get_capacity(rdev->bdev->bd_disk)
3451                                 - rdev->data_offset;
3452                 if (fit && (size == 0 || size > avail/2))
3453                         size = avail/2;
3454                 if (avail < ((sector_t)size << 1))
3455                         return -ENOSPC;
3456         }
3457         rv = mddev->pers->resize(mddev, (sector_t)size *2);
3458         if (!rv) {
3459                 struct block_device *bdev;
3460
3461                 bdev = bdget_disk(mddev->gendisk, 0);
3462                 if (bdev) {
3463                         down(&bdev->bd_inode->i_sem);
3464                         i_size_write(bdev->bd_inode, mddev->array_size << 10);
3465                         up(&bdev->bd_inode->i_sem);
3466                         bdput(bdev);
3467                 }
3468         }
3469         return rv;
3470 }
3471
3472 static int update_raid_disks(mddev_t *mddev, int raid_disks)
3473 {
3474         int rv;
3475         /* change the number of raid disks */
3476         if (mddev->pers->reshape == NULL)
3477                 return -EINVAL;
3478         if (raid_disks <= 0 ||
3479             raid_disks >= mddev->max_disks)
3480                 return -EINVAL;
3481         if (mddev->sync_thread)
3482                 return -EBUSY;
3483         rv = mddev->pers->reshape(mddev, raid_disks);
3484         if (!rv) {
3485                 struct block_device *bdev;
3486
3487                 bdev = bdget_disk(mddev->gendisk, 0);
3488                 if (bdev) {
3489                         down(&bdev->bd_inode->i_sem);
3490                         i_size_write(bdev->bd_inode, mddev->array_size << 10);
3491                         up(&bdev->bd_inode->i_sem);
3492                         bdput(bdev);
3493                 }
3494         }
3495         return rv;
3496 }
3497
3498
3499 /*
3500  * update_array_info is used to change the configuration of an
3501  * on-line array.
3502  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
3503  * fields in the info are checked against the array.
3504  * Any differences that cannot be handled will cause an error.
3505  * Normally, only one change can be managed at a time.
3506  */
3507 static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
3508 {
3509         int rv = 0;
3510         int cnt = 0;
3511         int state = 0;
3512
3513         /* calculate expected state,ignoring low bits */
3514         if (mddev->bitmap && mddev->bitmap_offset)
3515                 state |= (1 << MD_SB_BITMAP_PRESENT);
3516
3517         if (mddev->major_version != info->major_version ||
3518             mddev->minor_version != info->minor_version ||
3519 /*          mddev->patch_version != info->patch_version || */
3520             mddev->ctime         != info->ctime         ||
3521             mddev->level         != info->level         ||
3522 /*          mddev->layout        != info->layout        || */
3523             !mddev->persistent   != info->not_persistent||
3524             mddev->chunk_size    != info->chunk_size    ||
3525             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
3526             ((state^info->state) & 0xfffffe00)
3527                 )
3528                 return -EINVAL;
3529         /* Check there is only one change */
3530         if (mddev->size != info->size) cnt++;
3531         if (mddev->raid_disks != info->raid_disks) cnt++;
3532         if (mddev->layout != info->layout) cnt++;
3533         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
3534         if (cnt == 0) return 0;
3535         if (cnt > 1) return -EINVAL;
3536
3537         if (mddev->layout != info->layout) {
3538                 /* Change layout
3539                  * we don't need to do anything at the md level, the
3540                  * personality will take care of it all.
3541                  */
3542                 if (mddev->pers->reconfig == NULL)
3543                         return -EINVAL;
3544                 else
3545                         return mddev->pers->reconfig(mddev, info->layout, -1);
3546         }
3547         if (mddev->size != info->size)
3548                 rv = update_size(mddev, info->size);
3549
3550         if (mddev->raid_disks    != info->raid_disks)
3551                 rv = update_raid_disks(mddev, info->raid_disks);
3552
3553         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
3554                 if (mddev->pers->quiesce == NULL)
3555                         return -EINVAL;
3556                 if (mddev->recovery || mddev->sync_thread)
3557                         return -EBUSY;
3558                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
3559                         /* add the bitmap */
3560                         if (mddev->bitmap)
3561                                 return -EEXIST;
3562                         if (mddev->default_bitmap_offset == 0)
3563                                 return -EINVAL;
3564                         mddev->bitmap_offset = mddev->default_bitmap_offset;
3565                         mddev->pers->quiesce(mddev, 1);
3566                         rv = bitmap_create(mddev);
3567                         if (rv)
3568                                 bitmap_destroy(mddev);
3569                         mddev->pers->quiesce(mddev, 0);
3570                 } else {
3571                         /* remove the bitmap */
3572                         if (!mddev->bitmap)
3573                                 return -ENOENT;
3574                         if (mddev->bitmap->file)
3575                                 return -EINVAL;
3576                         mddev->pers->quiesce(mddev, 1);
3577                         bitmap_destroy(mddev);
3578                         mddev->pers->quiesce(mddev, 0);
3579                         mddev->bitmap_offset = 0;
3580                 }
3581         }
3582         md_update_sb(mddev);
3583         return rv;
3584 }
3585
3586 static int set_disk_faulty(mddev_t *mddev, dev_t dev)
3587 {
3588         mdk_rdev_t *rdev;
3589
3590         if (mddev->pers == NULL)
3591                 return -ENODEV;
3592
3593         rdev = find_rdev(mddev, dev);
3594         if (!rdev)
3595                 return -ENODEV;
3596
3597         md_error(mddev, rdev);
3598         return 0;
3599 }
3600
3601 static int md_ioctl(struct inode *inode, struct file *file,
3602                         unsigned int cmd, unsigned long arg)
3603 {
3604         int err = 0;
3605         void __user *argp = (void __user *)arg;
3606         struct hd_geometry __user *loc = argp;
3607         mddev_t *mddev = NULL;
3608
3609         if (!capable(CAP_SYS_ADMIN))
3610                 return -EACCES;
3611
3612         /*
3613          * Commands dealing with the RAID driver but not any
3614          * particular array:
3615          */
3616         switch (cmd)
3617         {
3618                 case RAID_VERSION:
3619                         err = get_version(argp);
3620                         goto done;
3621
3622                 case PRINT_RAID_DEBUG:
3623                         err = 0;
3624                         md_print_devices();
3625                         goto done;
3626
3627 #ifndef MODULE
3628                 case RAID_AUTORUN:
3629                         err = 0;
3630                         autostart_arrays(arg);
3631                         goto done;
3632 #endif
3633                 default:;
3634         }
3635
3636         /*
3637          * Commands creating/starting a new array:
3638          */
3639
3640         mddev = inode->i_bdev->bd_disk->private_data;
3641
3642         if (!mddev) {
3643                 BUG();
3644                 goto abort;
3645         }
3646
3647
3648         if (cmd == START_ARRAY) {
3649                 /* START_ARRAY doesn't need to lock the array as autostart_array
3650                  * does the locking, and it could even be a different array
3651                  */
3652                 static int cnt = 3;
3653                 if (cnt > 0 ) {
3654                         printk(KERN_WARNING
3655                                "md: %s(pid %d) used deprecated START_ARRAY ioctl. "
3656                                "This will not be supported beyond July 2006\n",
3657                                current->comm, current->pid);
3658                         cnt--;
3659                 }
3660                 err = autostart_array(new_decode_dev(arg));
3661                 if (err) {
3662                         printk(KERN_WARNING "md: autostart failed!\n");
3663                         goto abort;
3664                 }
3665                 goto done;
3666         }
3667
3668         err = mddev_lock(mddev);
3669         if (err) {
3670                 printk(KERN_INFO 
3671                         "md: ioctl lock interrupted, reason %d, cmd %d\n",
3672                         err, cmd);
3673                 goto abort;
3674         }
3675
3676         switch (cmd)
3677         {
3678                 case SET_ARRAY_INFO:
3679                         {
3680                                 mdu_array_info_t info;
3681                                 if (!arg)
3682                                         memset(&info, 0, sizeof(info));
3683                                 else if (copy_from_user(&info, argp, sizeof(info))) {
3684                                         err = -EFAULT;
3685                                         goto abort_unlock;
3686                                 }
3687                                 if (mddev->pers) {
3688                                         err = update_array_info(mddev, &info);
3689                                         if (err) {
3690                                                 printk(KERN_WARNING "md: couldn't update"
3691                                                        " array info. %d\n", err);
3692                                                 goto abort_unlock;
3693                                         }
3694                                         goto done_unlock;
3695                                 }
3696                                 if (!list_empty(&mddev->disks)) {
3697                                         printk(KERN_WARNING
3698                                                "md: array %s already has disks!\n",
3699                                                mdname(mddev));
3700                                         err = -EBUSY;
3701                                         goto abort_unlock;
3702                                 }
3703                                 if (mddev->raid_disks) {
3704                                         printk(KERN_WARNING
3705                                                "md: array %s already initialised!\n",
3706                                                mdname(mddev));
3707                                         err = -EBUSY;
3708                                         goto abort_unlock;
3709                                 }
3710                                 err = set_array_info(mddev, &info);
3711                                 if (err) {
3712                                         printk(KERN_WARNING "md: couldn't set"
3713                                                " array info. %d\n", err);
3714                                         goto abort_unlock;
3715                                 }
3716                         }
3717                         goto done_unlock;
3718
3719                 default:;
3720         }
3721
3722         /*
3723          * Commands querying/configuring an existing array:
3724          */
3725         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
3726          * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
3727         if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
3728                         && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
3729                 err = -ENODEV;
3730                 goto abort_unlock;
3731         }
3732
3733         /*
3734          * Commands even a read-only array can execute:
3735          */
3736         switch (cmd)
3737         {
3738                 case GET_ARRAY_INFO:
3739                         err = get_array_info(mddev, argp);
3740                         goto done_unlock;
3741
3742                 case GET_BITMAP_FILE:
3743                         err = get_bitmap_file(mddev, argp);
3744                         goto done_unlock;
3745
3746                 case GET_DISK_INFO:
3747                         err = get_disk_info(mddev, argp);
3748                         goto done_unlock;
3749
3750                 case RESTART_ARRAY_RW:
3751                         err = restart_array(mddev);
3752                         goto done_unlock;
3753
3754                 case STOP_ARRAY:
3755                         err = do_md_stop (mddev, 0);
3756                         goto done_unlock;
3757
3758                 case STOP_ARRAY_RO:
3759                         err = do_md_stop (mddev, 1);
3760                         goto done_unlock;
3761
3762         /*
3763          * We have a problem here : there is no easy way to give a CHS
3764          * virtual geometry. We currently pretend that we have a 2 heads
3765          * 4 sectors (with a BIG number of cylinders...). This drives
3766          * dosfs just mad... ;-)
3767          */
3768                 case HDIO_GETGEO:
3769                         if (!loc) {
3770                                 err = -EINVAL;
3771                                 goto abort_unlock;
3772                         }
3773                         err = put_user (2, (char __user *) &loc->heads);
3774                         if (err)
3775                                 goto abort_unlock;
3776                         err = put_user (4, (char __user *) &loc->sectors);
3777                         if (err)
3778                                 goto abort_unlock;
3779                         err = put_user(get_capacity(mddev->gendisk)/8,
3780                                         (short __user *) &loc->cylinders);
3781                         if (err)
3782                                 goto abort_unlock;
3783                         err = put_user (get_start_sect(inode->i_bdev),
3784                                                 (long __user *) &loc->start);
3785                         goto done_unlock;
3786         }
3787
3788         /*
3789          * The remaining ioctls are changing the state of the
3790          * superblock, so we do not allow them on read-only arrays.
3791          * However non-MD ioctls (e.g. get-size) will still come through
3792          * here and hit the 'default' below, so only disallow
3793          * 'md' ioctls, and switch to rw mode if started auto-readonly.
3794          */
3795         if (_IOC_TYPE(cmd) == MD_MAJOR &&
3796             mddev->ro && mddev->pers) {
3797                 if (mddev->ro == 2) {
3798                         mddev->ro = 0;
3799                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3800                 md_wakeup_thread(mddev->thread);
3801
3802                 } else {
3803                         err = -EROFS;
3804                         goto abort_unlock;
3805                 }
3806         }
3807
3808         switch (cmd)
3809         {
3810                 case ADD_NEW_DISK:
3811                 {
3812                         mdu_disk_info_t info;
3813                         if (copy_from_user(&info, argp, sizeof(info)))
3814                                 err = -EFAULT;
3815                         else
3816                                 err = add_new_disk(mddev, &info);
3817                         goto done_unlock;
3818                 }
3819
3820                 case HOT_REMOVE_DISK:
3821                         err = hot_remove_disk(mddev, new_decode_dev(arg));
3822                         goto done_unlock;
3823
3824                 case HOT_ADD_DISK:
3825                         err = hot_add_disk(mddev, new_decode_dev(arg));
3826                         goto done_unlock;
3827
3828                 case SET_DISK_FAULTY:
3829                         err = set_disk_faulty(mddev, new_decode_dev(arg));
3830                         goto done_unlock;
3831
3832                 case RUN_ARRAY:
3833                         err = do_md_run (mddev);
3834                         goto done_unlock;
3835
3836                 case SET_BITMAP_FILE:
3837                         err = set_bitmap_file(mddev, (int)arg);
3838                         goto done_unlock;
3839
3840                 default:
3841                         if (_IOC_TYPE(cmd) == MD_MAJOR)
3842                                 printk(KERN_WARNING "md: %s(pid %d) used"
3843                                         " obsolete MD ioctl, upgrade your"
3844                                         " software to use new ictls.\n",
3845                                         current->comm, current->pid);
3846                         err = -EINVAL;
3847                         goto abort_unlock;
3848         }
3849
3850 done_unlock:
3851 abort_unlock:
3852         mddev_unlock(mddev);
3853
3854         return err;
3855 done:
3856         if (err)
3857                 MD_BUG();
3858 abort:
3859         return err;
3860 }
3861
3862 static int md_open(struct inode *inode, struct file *file)
3863 {
3864         /*
3865          * Succeed if we can lock the mddev, which confirms that
3866          * it isn't being stopped right now.
3867          */
3868         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
3869         int err;
3870
3871         if ((err = mddev_lock(mddev)))
3872                 goto out;
3873
3874         err = 0;
3875         mddev_get(mddev);
3876         mddev_unlock(mddev);
3877
3878         check_disk_change(inode->i_bdev);
3879  out:
3880         return err;
3881 }
3882
3883 static int md_release(struct inode *inode, struct file * file)
3884 {
3885         mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
3886
3887         if (!mddev)
3888                 BUG();
3889         mddev_put(mddev);
3890
3891         return 0;
3892 }
3893
3894 static int md_media_changed(struct gendisk *disk)
3895 {
3896         mddev_t *mddev = disk->private_data;
3897
3898         return mddev->changed;
3899 }
3900
3901 static int md_revalidate(struct gendisk *disk)
3902 {
3903         mddev_t *mddev = disk->private_data;
3904
3905         mddev->changed = 0;
3906         return 0;
3907 }
3908 static struct block_device_operations md_fops =
3909 {
3910         .owner          = THIS_MODULE,
3911         .open           = md_open,
3912         .release        = md_release,
3913         .ioctl          = md_ioctl,
3914         .media_changed  = md_media_changed,
3915         .revalidate_disk= md_revalidate,
3916 };
3917
3918 static int md_thread(void * arg)
3919 {
3920         mdk_thread_t *thread = arg;
3921
3922         /*
3923          * md_thread is a 'system-thread', it's priority should be very
3924          * high. We avoid resource deadlocks individually in each
3925          * raid personality. (RAID5 does preallocation) We also use RR and
3926          * the very same RT priority as kswapd, thus we will never get
3927          * into a priority inversion deadlock.
3928          *
3929          * we definitely have to have equal or higher priority than
3930          * bdflush, otherwise bdflush will deadlock if there are too
3931          * many dirty RAID5 blocks.
3932          */
3933
3934         allow_signal(SIGKILL);
3935         while (!kthread_should_stop()) {
3936
3937                 /* We need to wait INTERRUPTIBLE so that
3938                  * we don't add to the load-average.
3939                  * That means we need to be sure no signals are
3940                  * pending
3941                  */
3942                 if (signal_pending(current))
3943                         flush_signals(current);
3944
3945                 wait_event_interruptible_timeout
3946                         (thread->wqueue,
3947                          test_bit(THREAD_WAKEUP, &thread->flags)
3948                          || kthread_should_stop(),
3949                          thread->timeout);
3950                 try_to_freeze();
3951
3952                 clear_bit(THREAD_WAKEUP, &thread->flags);
3953
3954                 thread->run(thread->mddev);
3955         }
3956
3957         return 0;
3958 }
3959
3960 void md_wakeup_thread(mdk_thread_t *thread)
3961 {
3962         if (thread) {
3963                 dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
3964                 set_bit(THREAD_WAKEUP, &thread->flags);
3965                 wake_up(&thread->wqueue);
3966         }
3967 }
3968
3969 mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
3970                                  const char *name)
3971 {
3972         mdk_thread_t *thread;
3973
3974         thread = kzalloc(sizeof(mdk_thread_t), GFP_KERNEL);
3975         if (!thread)
3976                 return NULL;
3977
3978         init_waitqueue_head(&thread->wqueue);
3979
3980         thread->run = run;
3981         thread->mddev = mddev;
3982         thread->timeout = MAX_SCHEDULE_TIMEOUT;
3983         thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
3984         if (IS_ERR(thread->tsk)) {
3985                 kfree(thread);
3986                 return NULL;
3987         }
3988         return thread;
3989 }
3990
3991 void md_unregister_thread(mdk_thread_t *thread)
3992 {
3993         dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
3994
3995         kthread_stop(thread->tsk);
3996         kfree(thread);
3997 }
3998
3999 void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
4000 {
4001         if (!mddev) {
4002                 MD_BUG();
4003                 return;
4004         }
4005
4006         if (!rdev || test_bit(Faulty, &rdev->flags))
4007                 return;
4008 /*
4009         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
4010                 mdname(mddev),
4011                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
4012                 __builtin_return_address(0),__builtin_return_address(1),
4013                 __builtin_return_address(2),__builtin_return_address(3));
4014 */
4015         if (!mddev->pers->error_handler)
4016                 return;
4017         mddev->pers->error_handler(mddev,rdev);
4018         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4019         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4020         md_wakeup_thread(mddev->thread);
4021         md_new_event(mddev);
4022 }
4023
4024 /* seq_file implementation /proc/mdstat */
4025
4026 static void status_unused(struct seq_file *seq)
4027 {
4028         int i = 0;
4029         mdk_rdev_t *rdev;
4030         struct list_head *tmp;
4031
4032         seq_printf(seq, "unused devices: ");
4033
4034         ITERATE_RDEV_PENDING(rdev,tmp) {
4035                 char b[BDEVNAME_SIZE];
4036                 i++;
4037                 seq_printf(seq, "%s ",
4038                               bdevname(rdev->bdev,b));
4039         }
4040         if (!i)
4041                 seq_printf(seq, "<none>");
4042
4043         seq_printf(seq, "\n");
4044 }
4045
4046
4047 static void status_resync(struct seq_file *seq, mddev_t * mddev)
4048 {
4049         unsigned long max_blocks, resync, res, dt, db, rt;
4050
4051         resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
4052
4053         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4054                 max_blocks = mddev->resync_max_sectors >> 1;
4055         else
4056                 max_blocks = mddev->size;
4057
4058         /*
4059          * Should not happen.
4060          */
4061         if (!max_blocks) {
4062                 MD_BUG();
4063                 return;
4064         }
4065         res = (resync/1024)*1000/(max_blocks/1024 + 1);
4066         {
4067                 int i, x = res/50, y = 20-x;
4068                 seq_printf(seq, "[");
4069                 for (i = 0; i < x; i++)
4070                         seq_printf(seq, "=");
4071                 seq_printf(seq, ">");
4072                 for (i = 0; i < y; i++)
4073                         seq_printf(seq, ".");
4074                 seq_printf(seq, "] ");
4075         }
4076         seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
4077                       (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
4078                        "resync" : "recovery"),
4079                       res/10, res % 10, resync, max_blocks);
4080
4081         /*
4082          * We do not want to overflow, so the order of operands and
4083          * the * 100 / 100 trick are important. We do a +1 to be
4084          * safe against division by zero. We only estimate anyway.
4085          *
4086          * dt: time from mark until now
4087          * db: blocks written from mark until now
4088          * rt: remaining time
4089          */
4090         dt = ((jiffies - mddev->resync_mark) / HZ);
4091         if (!dt) dt++;
4092         db = resync - (mddev->resync_mark_cnt/2);
4093         rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
4094
4095         seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
4096
4097         seq_printf(seq, " speed=%ldK/sec", db/dt);
4098 }
4099
4100 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
4101 {
4102         struct list_head *tmp;
4103         loff_t l = *pos;
4104         mddev_t *mddev;
4105
4106         if (l >= 0x10000)
4107                 return NULL;
4108         if (!l--)
4109                 /* header */
4110                 return (void*)1;
4111
4112         spin_lock(&all_mddevs_lock);
4113         list_for_each(tmp,&all_mddevs)
4114                 if (!l--) {
4115                         mddev = list_entry(tmp, mddev_t, all_mddevs);
4116                         mddev_get(mddev);
4117                         spin_unlock(&all_mddevs_lock);
4118                         return mddev;
4119                 }
4120         spin_unlock(&all_mddevs_lock);
4121         if (!l--)
4122                 return (void*)2;/* tail */
4123         return NULL;
4124 }
4125
4126 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4127 {
4128         struct list_head *tmp;
4129         mddev_t *next_mddev, *mddev = v;
4130         
4131         ++*pos;
4132         if (v == (void*)2)
4133                 return NULL;
4134
4135         spin_lock(&all_mddevs_lock);
4136         if (v == (void*)1)
4137                 tmp = all_mddevs.next;
4138         else
4139                 tmp = mddev->all_mddevs.next;
4140         if (tmp != &all_mddevs)
4141                 next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
4142         else {
4143                 next_mddev = (void*)2;
4144                 *pos = 0x10000;
4145         }               
4146         spin_unlock(&all_mddevs_lock);
4147
4148         if (v != (void*)1)
4149                 mddev_put(mddev);
4150         return next_mddev;
4151
4152 }
4153
4154 static void md_seq_stop(struct seq_file *seq, void *v)
4155 {
4156         mddev_t *mddev = v;
4157
4158         if (mddev && v != (void*)1 && v != (void*)2)
4159                 mddev_put(mddev);
4160 }
4161
4162 struct mdstat_info {
4163         int event;
4164 };
4165
4166 static int md_seq_show(struct seq_file *seq, void *v)
4167 {
4168         mddev_t *mddev = v;
4169         sector_t size;
4170         struct list_head *tmp2;
4171         mdk_rdev_t *rdev;
4172         struct mdstat_info *mi = seq->private;
4173         struct bitmap *bitmap;
4174
4175         if (v == (void*)1) {
4176                 struct mdk_personality *pers;
4177                 seq_printf(seq, "Personalities : ");
4178                 spin_lock(&pers_lock);
4179                 list_for_each_entry(pers, &pers_list, list)
4180                         seq_printf(seq, "[%s] ", pers->name);
4181
4182                 spin_unlock(&pers_lock);
4183                 seq_printf(seq, "\n");
4184                 mi->event = atomic_read(&md_event_count);
4185                 return 0;
4186         }
4187         if (v == (void*)2) {
4188                 status_unused(seq);
4189                 return 0;
4190         }
4191
4192         if (mddev_lock(mddev)!=0) 
4193                 return -EINTR;
4194         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
4195                 seq_printf(seq, "%s : %sactive", mdname(mddev),
4196                                                 mddev->pers ? "" : "in");
4197                 if (mddev->pers) {
4198                         if (mddev->ro==1)
4199                                 seq_printf(seq, " (read-only)");
4200                         if (mddev->ro==2)
4201                                 seq_printf(seq, "(auto-read-only)");
4202                         seq_printf(seq, " %s", mddev->pers->name);
4203                 }
4204
4205                 size = 0;
4206                 ITERATE_RDEV(mddev,rdev,tmp2) {
4207                         char b[BDEVNAME_SIZE];
4208                         seq_printf(seq, " %s[%d]",
4209                                 bdevname(rdev->bdev,b), rdev->desc_nr);
4210                         if (test_bit(WriteMostly, &rdev->flags))
4211                                 seq_printf(seq, "(W)");
4212                         if (test_bit(Faulty, &rdev->flags)) {
4213                                 seq_printf(seq, "(F)");
4214                                 continue;
4215                         } else if (rdev->raid_disk < 0)
4216                                 seq_printf(seq, "(S)"); /* spare */
4217                         size += rdev->size;
4218                 }
4219
4220                 if (!list_empty(&mddev->disks)) {
4221                         if (mddev->pers)
4222                                 seq_printf(seq, "\n      %llu blocks",
4223                                         (unsigned long long)mddev->array_size);
4224                         else
4225                                 seq_printf(seq, "\n      %llu blocks",
4226                                         (unsigned long long)size);
4227                 }
4228                 if (mddev->persistent) {
4229                         if (mddev->major_version != 0 ||
4230                             mddev->minor_version != 90) {
4231                                 seq_printf(seq," super %d.%d",
4232                                            mddev->major_version,
4233                                            mddev->minor_version);
4234                         }
4235                 } else
4236                         seq_printf(seq, " super non-persistent");
4237
4238                 if (mddev->pers) {
4239                         mddev->pers->status (seq, mddev);
4240                         seq_printf(seq, "\n      ");
4241                         if (mddev->pers->sync_request) {
4242                                 if (mddev->curr_resync > 2) {
4243                                         status_resync (seq, mddev);
4244                                         seq_printf(seq, "\n      ");
4245                                 } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
4246                                         seq_printf(seq, "\tresync=DELAYED\n      ");
4247                                 else if (mddev->recovery_cp < MaxSector)
4248                                         seq_printf(seq, "\tresync=PENDING\n      ");
4249                         }
4250                 } else
4251                         seq_printf(seq, "\n       ");
4252
4253                 if ((bitmap = mddev->bitmap)) {
4254                         unsigned long chunk_kb;
4255                         unsigned long flags;
4256                         spin_lock_irqsave(&bitmap->lock, flags);
4257                         chunk_kb = bitmap->chunksize >> 10;
4258                         seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
4259                                 "%lu%s chunk",
4260                                 bitmap->pages - bitmap->missing_pages,
4261                                 bitmap->pages,
4262                                 (bitmap->pages - bitmap->missing_pages)
4263                                         << (PAGE_SHIFT - 10),
4264                                 chunk_kb ? chunk_kb : bitmap->chunksize,
4265                                 chunk_kb ? "KB" : "B");
4266                         if (bitmap->file) {
4267                                 seq_printf(seq, ", file: ");
4268                                 seq_path(seq, bitmap->file->f_vfsmnt,
4269                                          bitmap->file->f_dentry," \t\n");
4270                         }
4271
4272                         seq_printf(seq, "\n");
4273                         spin_unlock_irqrestore(&bitmap->lock, flags);
4274                 }
4275
4276                 seq_printf(seq, "\n");
4277         }
4278         mddev_unlock(mddev);
4279         
4280         return 0;
4281 }
4282
4283 static struct seq_operations md_seq_ops = {
4284         .start  = md_seq_start,
4285         .next   = md_seq_next,
4286         .stop   = md_seq_stop,
4287         .show   = md_seq_show,
4288 };
4289
4290 static int md_seq_open(struct inode *inode, struct file *file)
4291 {
4292         int error;
4293         struct mdstat_info *mi = kmalloc(sizeof(*mi), GFP_KERNEL);
4294         if (mi == NULL)
4295                 return -ENOMEM;
4296
4297         error = seq_open(file, &md_seq_ops);
4298         if (error)
4299                 kfree(mi);
4300         else {
4301                 struct seq_file *p = file->private_data;
4302                 p->private = mi;
4303                 mi->event = atomic_read(&md_event_count);
4304         }
4305         return error;
4306 }
4307
4308 static int md_seq_release(struct inode *inode, struct file *file)
4309 {
4310         struct seq_file *m = file->private_data;
4311         struct mdstat_info *mi = m->private;
4312         m->private = NULL;
4313         kfree(mi);
4314         return seq_release(inode, file);
4315 }
4316
4317 static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
4318 {
4319         struct seq_file *m = filp->private_data;
4320         struct mdstat_info *mi = m->private;
4321         int mask;
4322
4323         poll_wait(filp, &md_event_waiters, wait);
4324
4325         /* always allow read */
4326         mask = POLLIN | POLLRDNORM;
4327
4328         if (mi->event != atomic_read(&md_event_count))
4329                 mask |= POLLERR | POLLPRI;
4330         return mask;
4331 }
4332
4333 static struct file_operations md_seq_fops = {
4334         .open           = md_seq_open,
4335         .read           = seq_read,
4336         .llseek         = seq_lseek,
4337         .release        = md_seq_release,
4338         .poll           = mdstat_poll,
4339 };
4340
4341 int register_md_personality(struct mdk_personality *p)
4342 {
4343         spin_lock(&pers_lock);
4344         list_add_tail(&p->list, &pers_list);
4345         printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
4346         spin_unlock(&pers_lock);
4347         return 0;
4348 }
4349
4350 int unregister_md_personality(struct mdk_personality *p)
4351 {
4352         printk(KERN_INFO "md: %s personality unregistered\n", p->name);
4353         spin_lock(&pers_lock);
4354         list_del_init(&p->list);
4355         spin_unlock(&pers_lock);
4356         return 0;
4357 }
4358
4359 static int is_mddev_idle(mddev_t *mddev)
4360 {
4361         mdk_rdev_t * rdev;
4362         struct list_head *tmp;
4363         int idle;
4364         unsigned long curr_events;
4365
4366         idle = 1;
4367         ITERATE_RDEV(mddev,rdev,tmp) {
4368                 struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
4369                 curr_events = disk_stat_read(disk, sectors[0]) + 
4370                                 disk_stat_read(disk, sectors[1]) - 
4371                                 atomic_read(&disk->sync_io);
4372                 /* The difference between curr_events and last_events
4373                  * will be affected by any new non-sync IO (making
4374                  * curr_events bigger) and any difference in the amount of
4375                  * in-flight syncio (making current_events bigger or smaller)
4376                  * The amount in-flight is currently limited to
4377                  * 32*64K in raid1/10 and 256*PAGE_SIZE in raid5/6
4378                  * which is at most 4096 sectors.
4379                  * These numbers are fairly fragile and should be made
4380                  * more robust, probably by enforcing the
4381                  * 'window size' that md_do_sync sort-of uses.
4382                  *
4383                  * Note: the following is an unsigned comparison.
4384                  */
4385                 if ((curr_events - rdev->last_events + 4096) > 8192) {
4386                         rdev->last_events = curr_events;
4387                         idle = 0;
4388                 }
4389         }
4390         return idle;
4391 }
4392
4393 void md_done_sync(mddev_t *mddev, int blocks, int ok)
4394 {
4395         /* another "blocks" (512byte) blocks have been synced */
4396         atomic_sub(blocks, &mddev->recovery_active);
4397         wake_up(&mddev->recovery_wait);
4398         if (!ok) {
4399                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
4400                 md_wakeup_thread(mddev->thread);
4401                 // stop recovery, signal do_sync ....
4402         }
4403 }
4404
4405
4406 /* md_write_start(mddev, bi)
4407  * If we need to update some array metadata (e.g. 'active' flag
4408  * in superblock) before writing, schedule a superblock update
4409  * and wait for it to complete.
4410  */
4411 void md_write_start(mddev_t *mddev, struct bio *bi)
4412 {
4413         if (bio_data_dir(bi) != WRITE)
4414                 return;
4415
4416         BUG_ON(mddev->ro == 1);
4417         if (mddev->ro == 2) {
4418                 /* need to switch to read/write */
4419                 mddev->ro = 0;
4420                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4421                 md_wakeup_thread(mddev->thread);
4422         }
4423         atomic_inc(&mddev->writes_pending);
4424         if (mddev->in_sync) {
4425                 spin_lock_irq(&mddev->write_lock);
4426                 if (mddev->in_sync) {
4427                         mddev->in_sync = 0;
4428                         mddev->sb_dirty = 1;
4429                         md_wakeup_thread(mddev->thread);
4430                 }
4431                 spin_unlock_irq(&mddev->write_lock);
4432         }
4433         wait_event(mddev->sb_wait, mddev->sb_dirty==0);
4434 }
4435
4436 void md_write_end(mddev_t *mddev)
4437 {
4438         if (atomic_dec_and_test(&mddev->writes_pending)) {
4439                 if (mddev->safemode == 2)
4440                         md_wakeup_thread(mddev->thread);
4441                 else
4442                         mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
4443         }
4444 }
4445
4446 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
4447
4448 #define SYNC_MARKS      10
4449 #define SYNC_MARK_STEP  (3*HZ)
4450 static void md_do_sync(mddev_t *mddev)
4451 {
4452         mddev_t *mddev2;
4453         unsigned int currspeed = 0,
4454                  window;
4455         sector_t max_sectors,j, io_sectors;
4456         unsigned long mark[SYNC_MARKS];
4457         sector_t mark_cnt[SYNC_MARKS];
4458         int last_mark,m;
4459         struct list_head *tmp;
4460         sector_t last_check;
4461         int skipped = 0;
4462
4463         /* just incase thread restarts... */
4464         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
4465                 return;
4466
4467         /* we overload curr_resync somewhat here.
4468          * 0 == not engaged in resync at all
4469          * 2 == checking that there is no conflict with another sync
4470          * 1 == like 2, but have yielded to allow conflicting resync to
4471          *              commense
4472          * other == active in resync - this many blocks
4473          *
4474          * Before starting a resync we must have set curr_resync to
4475          * 2, and then checked that every "conflicting" array has curr_resync
4476          * less than ours.  When we find one that is the same or higher
4477          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
4478          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
4479          * This will mean we have to start checking from the beginning again.
4480          *
4481          */
4482
4483         do {
4484                 mddev->curr_resync = 2;
4485
4486         try_again:
4487                 if (kthread_should_stop()) {
4488                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4489                         goto skip;
4490                 }
4491                 ITERATE_MDDEV(mddev2,tmp) {
4492                         if (mddev2 == mddev)
4493                                 continue;
4494                         if (mddev2->curr_resync && 
4495                             match_mddev_units(mddev,mddev2)) {
4496                                 DEFINE_WAIT(wq);
4497                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
4498                                         /* arbitrarily yield */
4499                                         mddev->curr_resync = 1;
4500                                         wake_up(&resync_wait);
4501                                 }
4502                                 if (mddev > mddev2 && mddev->curr_resync == 1)
4503                                         /* no need to wait here, we can wait the next
4504                                          * time 'round when curr_resync == 2
4505                                          */
4506                                         continue;
4507                                 prepare_to_wait(&resync_wait, &wq, TASK_UNINTERRUPTIBLE);
4508                                 if (!kthread_should_stop() &&
4509                                     mddev2->curr_resync >= mddev->curr_resync) {
4510                                         printk(KERN_INFO "md: delaying resync of %s"
4511                                                " until %s has finished resync (they"
4512                                                " share one or more physical units)\n",
4513                                                mdname(mddev), mdname(mddev2));
4514                                         mddev_put(mddev2);
4515                                         schedule();
4516                                         finish_wait(&resync_wait, &wq);
4517                                         goto try_again;
4518                                 }
4519                                 finish_wait(&resync_wait, &wq);
4520                         }
4521                 }
4522         } while (mddev->curr_resync < 2);
4523
4524         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
4525                 /* resync follows the size requested by the personality,
4526                  * which defaults to physical size, but can be virtual size
4527                  */
4528                 max_sectors = mddev->resync_max_sectors;
4529                 mddev->resync_mismatches = 0;
4530         } else
4531                 /* recovery follows the physical size of devices */
4532                 max_sectors = mddev->size << 1;
4533
4534         printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
4535         printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
4536                 " %d KB/sec/disc.\n", speed_min(mddev));
4537         printk(KERN_INFO "md: using maximum available idle IO bandwidth "
4538                "(but not more than %d KB/sec) for reconstruction.\n",
4539                speed_max(mddev));
4540
4541         is_mddev_idle(mddev); /* this also initializes IO event counters */
4542         /* we don't use the checkpoint if there's a bitmap */
4543         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap
4544             && ! test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
4545                 j = mddev->recovery_cp;
4546         else
4547                 j = 0;
4548         io_sectors = 0;
4549         for (m = 0; m < SYNC_MARKS; m++) {
4550                 mark[m] = jiffies;
4551                 mark_cnt[m] = io_sectors;
4552         }
4553         last_mark = 0;
4554         mddev->resync_mark = mark[last_mark];
4555         mddev->resync_mark_cnt = mark_cnt[last_mark];
4556
4557         /*
4558          * Tune reconstruction:
4559          */
4560         window = 32*(PAGE_SIZE/512);
4561         printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
4562                 window/2,(unsigned long long) max_sectors/2);
4563
4564         atomic_set(&mddev->recovery_active, 0);
4565         init_waitqueue_head(&mddev->recovery_wait);
4566         last_check = 0;
4567
4568         if (j>2) {
4569                 printk(KERN_INFO 
4570                         "md: resuming recovery of %s from checkpoint.\n",
4571                         mdname(mddev));
4572                 mddev->curr_resync = j;
4573         }
4574
4575         while (j < max_sectors) {
4576                 sector_t sectors;
4577
4578                 skipped = 0;
4579                 sectors = mddev->pers->sync_request(mddev, j, &skipped,
4580                                             currspeed < speed_min(mddev));
4581                 if (sectors == 0) {
4582                         set_bit(MD_RECOVERY_ERR, &mddev->recovery);
4583                         goto out;
4584                 }
4585
4586                 if (!skipped) { /* actual IO requested */
4587                         io_sectors += sectors;
4588                         atomic_add(sectors, &mddev->recovery_active);
4589                 }
4590
4591                 j += sectors;
4592                 if (j>1) mddev->curr_resync = j;
4593                 if (last_check == 0)
4594                         /* this is the earliers that rebuilt will be
4595                          * visible in /proc/mdstat
4596                          */
4597                         md_new_event(mddev);
4598
4599                 if (last_check + window > io_sectors || j == max_sectors)
4600                         continue;
4601
4602                 last_check = io_sectors;
4603
4604                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
4605                     test_bit(MD_RECOVERY_ERR, &mddev->recovery))
4606                         break;
4607
4608         repeat:
4609                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
4610                         /* step marks */
4611                         int next = (last_mark+1) % SYNC_MARKS;
4612
4613                         mddev->resync_mark = mark[next];
4614                         mddev->resync_mark_cnt = mark_cnt[next];
4615                         mark[next] = jiffies;
4616                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
4617                         last_mark = next;
4618                 }
4619
4620
4621                 if (kthread_should_stop()) {
4622                         /*
4623                          * got a signal, exit.
4624                          */
4625                         printk(KERN_INFO 
4626                                 "md: md_do_sync() got signal ... exiting\n");
4627                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4628                         goto out;
4629                 }
4630
4631                 /*
4632                  * this loop exits only if either when we are slower than
4633                  * the 'hard' speed limit, or the system was IO-idle for
4634                  * a jiffy.
4635                  * the system might be non-idle CPU-wise, but we only care
4636                  * about not overloading the IO subsystem. (things like an
4637                  * e2fsck being done on the RAID array should execute fast)
4638                  */
4639                 mddev->queue->unplug_fn(mddev->queue);
4640                 cond_resched();
4641
4642                 currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
4643                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
4644
4645                 if (currspeed > speed_min(mddev)) {
4646                         if ((currspeed > speed_max(mddev)) ||
4647                                         !is_mddev_idle(mddev)) {
4648                                 msleep(500);
4649                                 goto repeat;
4650                         }
4651                 }
4652         }
4653         printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
4654         /*
4655          * this also signals 'finished resyncing' to md_stop
4656          */
4657  out:
4658         mddev->queue->unplug_fn(mddev->queue);
4659
4660         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
4661
4662         /* tell personality that we are finished */
4663         mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
4664
4665         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
4666             mddev->curr_resync > 2 &&
4667             mddev->curr_resync >= mddev->recovery_cp) {
4668                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
4669                         printk(KERN_INFO 
4670                                 "md: checkpointing recovery of %s.\n",
4671                                 mdname(mddev));
4672                         mddev->recovery_cp = mddev->curr_resync;
4673                 } else
4674                         mddev->recovery_cp = MaxSector;
4675         }
4676
4677  skip:
4678         mddev->curr_resync = 0;
4679         wake_up(&resync_wait);
4680         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
4681         md_wakeup_thread(mddev->thread);
4682 }
4683
4684
4685 /*
4686  * This routine is regularly called by all per-raid-array threads to
4687  * deal with generic issues like resync and super-block update.
4688  * Raid personalities that don't have a thread (linear/raid0) do not
4689  * need this as they never do any recovery or update the superblock.
4690  *
4691  * It does not do any resync itself, but rather "forks" off other threads
4692  * to do that as needed.
4693  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
4694  * "->recovery" and create a thread at ->sync_thread.
4695  * When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
4696  * and wakeups up this thread which will reap the thread and finish up.
4697  * This thread also removes any faulty devices (with nr_pending == 0).
4698  *
4699  * The overall approach is:
4700  *  1/ if the superblock needs updating, update it.
4701  *  2/ If a recovery thread is running, don't do anything else.
4702  *  3/ If recovery has finished, clean up, possibly marking spares active.
4703  *  4/ If there are any faulty devices, remove them.
4704  *  5/ If array is degraded, try to add spares devices
4705  *  6/ If array has spares or is not in-sync, start a resync thread.
4706  */
4707 void md_check_recovery(mddev_t *mddev)
4708 {
4709         mdk_rdev_t *rdev;
4710         struct list_head *rtmp;
4711
4712
4713         if (mddev->bitmap)
4714                 bitmap_daemon_work(mddev->bitmap);
4715
4716         if (mddev->ro)
4717                 return;
4718
4719         if (signal_pending(current)) {
4720                 if (mddev->pers->sync_request) {
4721                         printk(KERN_INFO "md: %s in immediate safe mode\n",
4722                                mdname(mddev));
4723                         mddev->safemode = 2;
4724                 }
4725                 flush_signals(current);
4726         }
4727
4728         if ( ! (
4729                 mddev->sb_dirty ||
4730                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
4731                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
4732                 (mddev->safemode == 1) ||
4733                 (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
4734                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
4735                 ))
4736                 return;
4737
4738         if (mddev_trylock(mddev)==0) {
4739                 int spares =0;
4740
4741                 spin_lock_irq(&mddev->write_lock);
4742                 if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
4743                     !mddev->in_sync && mddev->recovery_cp == MaxSector) {
4744                         mddev->in_sync = 1;
4745                         mddev->sb_dirty = 1;
4746                 }
4747                 if (mddev->safemode == 1)
4748                         mddev->safemode = 0;
4749                 spin_unlock_irq(&mddev->write_lock);
4750
4751                 if (mddev->sb_dirty)
4752                         md_update_sb(mddev);
4753
4754
4755                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
4756                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
4757                         /* resync/recovery still happening */
4758                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4759                         goto unlock;
4760                 }
4761                 if (mddev->sync_thread) {
4762                         /* resync has finished, collect result */
4763                         md_unregister_thread(mddev->sync_thread);
4764                         mddev->sync_thread = NULL;
4765                         if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
4766                             !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
4767                                 /* success...*/
4768                                 /* activate any spares */
4769                                 mddev->pers->spare_active(mddev);
4770                         }
4771                         md_update_sb(mddev);
4772
4773                         /* if array is no-longer degraded, then any saved_raid_disk
4774                          * information must be scrapped
4775                          */
4776                         if (!mddev->degraded)
4777                                 ITERATE_RDEV(mddev,rdev,rtmp)
4778                                         rdev->saved_raid_disk = -1;
4779
4780                         mddev->recovery = 0;
4781                         /* flag recovery needed just to double check */
4782                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4783                         md_new_event(mddev);
4784                         goto unlock;
4785                 }
4786                 /* Clear some bits that don't mean anything, but
4787                  * might be left set
4788                  */
4789                 clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4790                 clear_bit(MD_RECOVERY_ERR, &mddev->recovery);
4791                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
4792                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
4793
4794                 /* no recovery is running.
4795                  * remove any failed drives, then
4796                  * add spares if possible.
4797                  * Spare are also removed and re-added, to allow
4798                  * the personality to fail the re-add.
4799                  */
4800                 ITERATE_RDEV(mddev,rdev,rtmp)
4801                         if (rdev->raid_disk >= 0 &&
4802                             (test_bit(Faulty, &rdev->flags) || ! test_bit(In_sync, &rdev->flags)) &&
4803                             atomic_read(&rdev->nr_pending)==0) {
4804                                 if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0) {
4805                                         char nm[20];
4806                                         sprintf(nm,"rd%d", rdev->raid_disk);
4807                                         sysfs_remove_link(&mddev->kobj, nm);
4808                                         rdev->raid_disk = -1;
4809                                 }
4810                         }
4811
4812                 if (mddev->degraded) {
4813                         ITERATE_RDEV(mddev,rdev,rtmp)
4814                                 if (rdev->raid_disk < 0
4815                                     && !test_bit(Faulty, &rdev->flags)) {
4816                                         if (mddev->pers->hot_add_disk(mddev,rdev)) {
4817                                                 char nm[20];
4818                                                 sprintf(nm, "rd%d", rdev->raid_disk);
4819                                                 sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
4820                                                 spares++;
4821                                                 md_new_event(mddev);
4822                                         } else
4823                                                 break;
4824                                 }
4825                 }
4826
4827                 if (spares) {
4828                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4829                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4830                 } else if (mddev->recovery_cp < MaxSector) {
4831                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4832                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4833                         /* nothing to be done ... */
4834                         goto unlock;
4835
4836                 if (mddev->pers->sync_request) {
4837                         set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
4838                         if (spares && mddev->bitmap && ! mddev->bitmap->file) {
4839                                 /* We are adding a device or devices to an array
4840                                  * which has the bitmap stored on all devices.
4841                                  * So make sure all bitmap pages get written
4842                                  */
4843                                 bitmap_write_all(mddev->bitmap);
4844                         }
4845                         mddev->sync_thread = md_register_thread(md_do_sync,
4846                                                                 mddev,
4847                                                                 "%s_resync");
4848                         if (!mddev->sync_thread) {
4849                                 printk(KERN_ERR "%s: could not start resync"
4850                                         " thread...\n", 
4851                                         mdname(mddev));
4852                                 /* leave the spares where they are, it shouldn't hurt */
4853                                 mddev->recovery = 0;
4854                         } else
4855                                 md_wakeup_thread(mddev->sync_thread);
4856                         md_new_event(mddev);
4857                 }
4858         unlock:
4859                 mddev_unlock(mddev);
4860         }
4861 }
4862
4863 static int md_notify_reboot(struct notifier_block *this,
4864                             unsigned long code, void *x)
4865 {
4866         struct list_head *tmp;
4867         mddev_t *mddev;
4868
4869         if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
4870
4871                 printk(KERN_INFO "md: stopping all md devices.\n");
4872
4873                 ITERATE_MDDEV(mddev,tmp)
4874                         if (mddev_trylock(mddev)==0)
4875                                 do_md_stop (mddev, 1);
4876                 /*
4877                  * certain more exotic SCSI devices are known to be
4878                  * volatile wrt too early system reboots. While the
4879                  * right place to handle this issue is the given
4880                  * driver, we do want to have a safe RAID driver ...
4881                  */
4882                 mdelay(1000*1);
4883         }
4884         return NOTIFY_DONE;
4885 }
4886
4887 static struct notifier_block md_notifier = {
4888         .notifier_call  = md_notify_reboot,
4889         .next           = NULL,
4890         .priority       = INT_MAX, /* before any real devices */
4891 };
4892
4893 static void md_geninit(void)
4894 {
4895         struct proc_dir_entry *p;
4896
4897         dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
4898
4899         p = create_proc_entry("mdstat", S_IRUGO, NULL);
4900         if (p)
4901                 p->proc_fops = &md_seq_fops;
4902 }
4903
4904 static int __init md_init(void)
4905 {
4906         int minor;
4907
4908         printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
4909                         " MD_SB_DISKS=%d\n",
4910                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
4911                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
4912         printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR_HI,
4913                         BITMAP_MINOR);
4914
4915         if (register_blkdev(MAJOR_NR, "md"))
4916                 return -1;
4917         if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
4918                 unregister_blkdev(MAJOR_NR, "md");
4919                 return -1;
4920         }
4921         devfs_mk_dir("md");
4922         blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
4923                                 md_probe, NULL, NULL);
4924         blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
4925                             md_probe, NULL, NULL);
4926
4927         for (minor=0; minor < MAX_MD_DEVS; ++minor)
4928                 devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
4929                                 S_IFBLK|S_IRUSR|S_IWUSR,
4930                                 "md/%d", minor);
4931
4932         for (minor=0; minor < MAX_MD_DEVS; ++minor)
4933                 devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
4934                               S_IFBLK|S_IRUSR|S_IWUSR,
4935                               "md/mdp%d", minor);
4936
4937
4938         register_reboot_notifier(&md_notifier);
4939         raid_table_header = register_sysctl_table(raid_root_table, 1);
4940
4941         md_geninit();
4942         return (0);
4943 }
4944
4945
4946 #ifndef MODULE
4947
4948 /*
4949  * Searches all registered partitions for autorun RAID arrays
4950  * at boot time.
4951  */
4952 static dev_t detected_devices[128];
4953 static int dev_cnt;
4954
4955 void md_autodetect_dev(dev_t dev)
4956 {
4957         if (dev_cnt >= 0 && dev_cnt < 127)
4958                 detected_devices[dev_cnt++] = dev;
4959 }
4960
4961
4962 static void autostart_arrays(int part)
4963 {
4964         mdk_rdev_t *rdev;
4965         int i;
4966
4967         printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
4968
4969         for (i = 0; i < dev_cnt; i++) {
4970                 dev_t dev = detected_devices[i];
4971
4972                 rdev = md_import_device(dev,0, 0);
4973                 if (IS_ERR(rdev))
4974                         continue;
4975
4976                 if (test_bit(Faulty, &rdev->flags)) {
4977                         MD_BUG();
4978                         continue;
4979                 }
4980                 list_add(&rdev->same_set, &pending_raid_disks);
4981         }
4982         dev_cnt = 0;
4983
4984         autorun_devices(part);
4985 }
4986
4987 #endif
4988
4989 static __exit void md_exit(void)
4990 {
4991         mddev_t *mddev;
4992         struct list_head *tmp;
4993         int i;
4994         blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
4995         blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
4996         for (i=0; i < MAX_MD_DEVS; i++)
4997                 devfs_remove("md/%d", i);
4998         for (i=0; i < MAX_MD_DEVS; i++)
4999                 devfs_remove("md/d%d", i);
5000
5001         devfs_remove("md");
5002
5003         unregister_blkdev(MAJOR_NR,"md");
5004         unregister_blkdev(mdp_major, "mdp");
5005         unregister_reboot_notifier(&md_notifier);
5006         unregister_sysctl_table(raid_table_header);
5007         remove_proc_entry("mdstat", NULL);
5008         ITERATE_MDDEV(mddev,tmp) {
5009                 struct gendisk *disk = mddev->gendisk;
5010                 if (!disk)
5011                         continue;
5012                 export_array(mddev);
5013                 del_gendisk(disk);
5014                 put_disk(disk);
5015                 mddev->gendisk = NULL;
5016                 mddev_put(mddev);
5017         }
5018 }
5019
5020 module_init(md_init)
5021 module_exit(md_exit)
5022
5023 static int get_ro(char *buffer, struct kernel_param *kp)
5024 {
5025         return sprintf(buffer, "%d", start_readonly);
5026 }
5027 static int set_ro(const char *val, struct kernel_param *kp)
5028 {
5029         char *e;
5030         int num = simple_strtoul(val, &e, 10);
5031         if (*val && (*e == '\0' || *e == '\n')) {
5032                 start_readonly = num;
5033                 return 0;
5034         }
5035         return -EINVAL;
5036 }
5037
5038 module_param_call(start_ro, set_ro, get_ro, NULL, 0600);
5039 module_param(start_dirty_degraded, int, 0644);
5040
5041
5042 EXPORT_SYMBOL(register_md_personality);
5043 EXPORT_SYMBOL(unregister_md_personality);
5044 EXPORT_SYMBOL(md_error);
5045 EXPORT_SYMBOL(md_done_sync);
5046 EXPORT_SYMBOL(md_write_start);
5047 EXPORT_SYMBOL(md_write_end);
5048 EXPORT_SYMBOL(md_register_thread);
5049 EXPORT_SYMBOL(md_unregister_thread);
5050 EXPORT_SYMBOL(md_wakeup_thread);
5051 EXPORT_SYMBOL(md_print_devices);
5052 EXPORT_SYMBOL(md_check_recovery);
5053 MODULE_LICENSE("GPL");
5054 MODULE_ALIAS("md");
5055 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);