xref: /linux/drivers/md/md.c (revision 9b960d8cd6f712cb2c03e2bdd4d5ca058238037f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3    md.c : Multiple Devices driver for Linux
4      Copyright (C) 1998, 1999, 2000 Ingo Molnar
5 
6      completely rewritten, based on the MD driver code from Marc Zyngier
7 
8    Changes:
9 
10    - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
11    - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
12    - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
13    - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
14    - kmod support by: Cyrus Durgin
15    - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
16    - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
17 
18    - lots of fixes and improvements to the RAID1/RAID5 and generic
19      RAID code (such as request based resynchronization):
20 
21      Neil Brown <neilb@cse.unsw.edu.au>.
22 
23    - persistent bitmap code
24      Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
25 
26 
27    Errors, Warnings, etc.
28    Please use:
29      pr_crit() for error conditions that risk data loss
30      pr_err() for error conditions that are unexpected, like an IO error
31          or internal inconsistency
32      pr_warn() for error conditions that could have been predicated, like
33          adding a device to an array when it has incompatible metadata
34      pr_info() for every interesting, very rare events, like an array starting
35          or stopping, or resync starting or stopping
36      pr_debug() for everything else.
37 
38 */
39 
40 #include <linux/sched/mm.h>
41 #include <linux/sched/signal.h>
42 #include <linux/kthread.h>
43 #include <linux/blkdev.h>
44 #include <linux/blk-integrity.h>
45 #include <linux/badblocks.h>
46 #include <linux/sysctl.h>
47 #include <linux/seq_file.h>
48 #include <linux/fs.h>
49 #include <linux/poll.h>
50 #include <linux/ctype.h>
51 #include <linux/string.h>
52 #include <linux/hdreg.h>
53 #include <linux/proc_fs.h>
54 #include <linux/random.h>
55 #include <linux/major.h>
56 #include <linux/module.h>
57 #include <linux/reboot.h>
58 #include <linux/file.h>
59 #include <linux/compat.h>
60 #include <linux/delay.h>
61 #include <linux/raid/md_p.h>
62 #include <linux/raid/md_u.h>
63 #include <linux/raid/detect.h>
64 #include <linux/slab.h>
65 #include <linux/percpu-refcount.h>
66 #include <linux/part_stat.h>
67 
68 #include "md.h"
69 #include "md-bitmap.h"
70 #include "md-cluster.h"
71 
72 static const char *action_name[NR_SYNC_ACTIONS] = {
73 	[ACTION_RESYNC]		= "resync",
74 	[ACTION_RECOVER]	= "recover",
75 	[ACTION_CHECK]		= "check",
76 	[ACTION_REPAIR]		= "repair",
77 	[ACTION_RESHAPE]	= "reshape",
78 	[ACTION_FROZEN]		= "frozen",
79 	[ACTION_IDLE]		= "idle",
80 };
81 
82 static DEFINE_XARRAY(md_submodule);
83 
84 static const struct kobj_type md_ktype;
85 
86 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
87 static struct workqueue_struct *md_wq;
88 
89 /*
90  * This workqueue is used for sync_work to register new sync_thread, and for
91  * del_work to remove rdev, and for event_work that is only set by dm-raid.
92  *
93  * Noted that sync_work will grab reconfig_mutex, hence never flush this
94  * workqueue whith reconfig_mutex grabbed.
95  */
96 static struct workqueue_struct *md_misc_wq;
97 struct workqueue_struct *md_bitmap_wq;
98 
99 static int remove_and_add_spares(struct mddev *mddev,
100 				 struct md_rdev *this);
101 static void mddev_detach(struct mddev *mddev);
102 static void export_rdev(struct md_rdev *rdev, struct mddev *mddev);
103 static void md_wakeup_thread_directly(struct md_thread __rcu *thread);
104 
105 /*
106  * Default number of read corrections we'll attempt on an rdev
107  * before ejecting it from the array. We divide the read error
108  * count by 2 for every hour elapsed between read errors.
109  */
110 #define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20
111 /* Default safemode delay: 200 msec */
112 #define DEFAULT_SAFEMODE_DELAY ((200 * HZ)/1000 +1)
113 /*
114  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
115  * is 1000 KB/sec, so the extra system load does not show up that much.
116  * Increase it if you want to have more _guaranteed_ speed. Note that
117  * the RAID driver will use the maximum available bandwidth if the IO
118  * subsystem is idle. There is also an 'absolute maximum' reconstruction
119  * speed limit - in case reconstruction slows down your system despite
120  * idle IO detection.
121  *
122  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
123  * or /sys/block/mdX/md/sync_speed_{min,max}
124  */
125 
126 static int sysctl_speed_limit_min = 1000;
127 static int sysctl_speed_limit_max = 200000;
speed_min(struct mddev * mddev)128 static inline int speed_min(struct mddev *mddev)
129 {
130 	return mddev->sync_speed_min ?
131 		mddev->sync_speed_min : sysctl_speed_limit_min;
132 }
133 
speed_max(struct mddev * mddev)134 static inline int speed_max(struct mddev *mddev)
135 {
136 	return mddev->sync_speed_max ?
137 		mddev->sync_speed_max : sysctl_speed_limit_max;
138 }
139 
rdev_uninit_serial(struct md_rdev * rdev)140 static void rdev_uninit_serial(struct md_rdev *rdev)
141 {
142 	if (!test_and_clear_bit(CollisionCheck, &rdev->flags))
143 		return;
144 
145 	kvfree(rdev->serial);
146 	rdev->serial = NULL;
147 }
148 
rdevs_uninit_serial(struct mddev * mddev)149 static void rdevs_uninit_serial(struct mddev *mddev)
150 {
151 	struct md_rdev *rdev;
152 
153 	rdev_for_each(rdev, mddev)
154 		rdev_uninit_serial(rdev);
155 }
156 
rdev_init_serial(struct md_rdev * rdev)157 static int rdev_init_serial(struct md_rdev *rdev)
158 {
159 	/* serial_nums equals with BARRIER_BUCKETS_NR */
160 	int i, serial_nums = 1 << ((PAGE_SHIFT - ilog2(sizeof(atomic_t))));
161 	struct serial_in_rdev *serial = NULL;
162 
163 	if (test_bit(CollisionCheck, &rdev->flags))
164 		return 0;
165 
166 	serial = kvmalloc(sizeof(struct serial_in_rdev) * serial_nums,
167 			  GFP_KERNEL);
168 	if (!serial)
169 		return -ENOMEM;
170 
171 	for (i = 0; i < serial_nums; i++) {
172 		struct serial_in_rdev *serial_tmp = &serial[i];
173 
174 		spin_lock_init(&serial_tmp->serial_lock);
175 		serial_tmp->serial_rb = RB_ROOT_CACHED;
176 		init_waitqueue_head(&serial_tmp->serial_io_wait);
177 	}
178 
179 	rdev->serial = serial;
180 	set_bit(CollisionCheck, &rdev->flags);
181 
182 	return 0;
183 }
184 
rdevs_init_serial(struct mddev * mddev)185 static int rdevs_init_serial(struct mddev *mddev)
186 {
187 	struct md_rdev *rdev;
188 	int ret = 0;
189 
190 	rdev_for_each(rdev, mddev) {
191 		ret = rdev_init_serial(rdev);
192 		if (ret)
193 			break;
194 	}
195 
196 	/* Free all resources if pool is not existed */
197 	if (ret && !mddev->serial_info_pool)
198 		rdevs_uninit_serial(mddev);
199 
200 	return ret;
201 }
202 
203 /*
204  * rdev needs to enable serial stuffs if it meets the conditions:
205  * 1. it is multi-queue device flaged with writemostly.
206  * 2. the write-behind mode is enabled.
207  */
rdev_need_serial(struct md_rdev * rdev)208 static int rdev_need_serial(struct md_rdev *rdev)
209 {
210 	return (rdev && rdev->mddev->bitmap_info.max_write_behind > 0 &&
211 		rdev->bdev->bd_disk->queue->nr_hw_queues != 1 &&
212 		test_bit(WriteMostly, &rdev->flags));
213 }
214 
215 /*
216  * Init resource for rdev(s), then create serial_info_pool if:
217  * 1. rdev is the first device which return true from rdev_enable_serial.
218  * 2. rdev is NULL, means we want to enable serialization for all rdevs.
219  */
mddev_create_serial_pool(struct mddev * mddev,struct md_rdev * rdev)220 void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev)
221 {
222 	int ret = 0;
223 
224 	if (rdev && !rdev_need_serial(rdev) &&
225 	    !test_bit(CollisionCheck, &rdev->flags))
226 		return;
227 
228 	if (!rdev)
229 		ret = rdevs_init_serial(mddev);
230 	else
231 		ret = rdev_init_serial(rdev);
232 	if (ret)
233 		return;
234 
235 	if (mddev->serial_info_pool == NULL) {
236 		/*
237 		 * already in memalloc noio context by
238 		 * mddev_suspend()
239 		 */
240 		mddev->serial_info_pool =
241 			mempool_create_kmalloc_pool(NR_SERIAL_INFOS,
242 						sizeof(struct serial_info));
243 		if (!mddev->serial_info_pool) {
244 			rdevs_uninit_serial(mddev);
245 			pr_err("can't alloc memory pool for serialization\n");
246 		}
247 	}
248 }
249 
250 /*
251  * Free resource from rdev(s), and destroy serial_info_pool under conditions:
252  * 1. rdev is the last device flaged with CollisionCheck.
253  * 2. when bitmap is destroyed while policy is not enabled.
254  * 3. for disable policy, the pool is destroyed only when no rdev needs it.
255  */
mddev_destroy_serial_pool(struct mddev * mddev,struct md_rdev * rdev)256 void mddev_destroy_serial_pool(struct mddev *mddev, struct md_rdev *rdev)
257 {
258 	if (rdev && !test_bit(CollisionCheck, &rdev->flags))
259 		return;
260 
261 	if (mddev->serial_info_pool) {
262 		struct md_rdev *temp;
263 		int num = 0; /* used to track if other rdevs need the pool */
264 
265 		rdev_for_each(temp, mddev) {
266 			if (!rdev) {
267 				if (!mddev->serialize_policy ||
268 				    !rdev_need_serial(temp))
269 					rdev_uninit_serial(temp);
270 				else
271 					num++;
272 			} else if (temp != rdev &&
273 				   test_bit(CollisionCheck, &temp->flags))
274 				num++;
275 		}
276 
277 		if (rdev)
278 			rdev_uninit_serial(rdev);
279 
280 		if (num)
281 			pr_info("The mempool could be used by other devices\n");
282 		else {
283 			mempool_destroy(mddev->serial_info_pool);
284 			mddev->serial_info_pool = NULL;
285 		}
286 	}
287 }
288 
289 static struct ctl_table_header *raid_table_header;
290 
291 static const struct ctl_table raid_table[] = {
292 	{
293 		.procname	= "speed_limit_min",
294 		.data		= &sysctl_speed_limit_min,
295 		.maxlen		= sizeof(int),
296 		.mode		= S_IRUGO|S_IWUSR,
297 		.proc_handler	= proc_dointvec,
298 	},
299 	{
300 		.procname	= "speed_limit_max",
301 		.data		= &sysctl_speed_limit_max,
302 		.maxlen		= sizeof(int),
303 		.mode		= S_IRUGO|S_IWUSR,
304 		.proc_handler	= proc_dointvec,
305 	},
306 };
307 
308 static int start_readonly;
309 
310 /*
311  * The original mechanism for creating an md device is to create
312  * a device node in /dev and to open it.  This causes races with device-close.
313  * The preferred method is to write to the "new_array" module parameter.
314  * This can avoid races.
315  * Setting create_on_open to false disables the original mechanism
316  * so all the races disappear.
317  */
318 static bool create_on_open = true;
319 
320 /*
321  * We have a system wide 'event count' that is incremented
322  * on any 'interesting' event, and readers of /proc/mdstat
323  * can use 'poll' or 'select' to find out when the event
324  * count increases.
325  *
326  * Events are:
327  *  start array, stop array, error, add device, remove device,
328  *  start build, activate spare
329  */
330 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
331 static atomic_t md_event_count;
md_new_event(void)332 void md_new_event(void)
333 {
334 	atomic_inc(&md_event_count);
335 	wake_up(&md_event_waiters);
336 }
337 EXPORT_SYMBOL_GPL(md_new_event);
338 
339 /*
340  * Enables to iterate over all existing md arrays
341  * all_mddevs_lock protects this list.
342  */
343 static LIST_HEAD(all_mddevs);
344 static DEFINE_SPINLOCK(all_mddevs_lock);
345 
is_md_suspended(struct mddev * mddev)346 static bool is_md_suspended(struct mddev *mddev)
347 {
348 	return percpu_ref_is_dying(&mddev->active_io);
349 }
350 /* Rather than calling directly into the personality make_request function,
351  * IO requests come here first so that we can check if the device is
352  * being suspended pending a reconfiguration.
353  * We hold a refcount over the call to ->make_request.  By the time that
354  * call has finished, the bio has been linked into some internal structure
355  * and so is visible to ->quiesce(), so we don't need the refcount any more.
356  */
is_suspended(struct mddev * mddev,struct bio * bio)357 static bool is_suspended(struct mddev *mddev, struct bio *bio)
358 {
359 	if (is_md_suspended(mddev))
360 		return true;
361 	if (bio_data_dir(bio) != WRITE)
362 		return false;
363 	if (READ_ONCE(mddev->suspend_lo) >= READ_ONCE(mddev->suspend_hi))
364 		return false;
365 	if (bio->bi_iter.bi_sector >= READ_ONCE(mddev->suspend_hi))
366 		return false;
367 	if (bio_end_sector(bio) < READ_ONCE(mddev->suspend_lo))
368 		return false;
369 	return true;
370 }
371 
md_handle_request(struct mddev * mddev,struct bio * bio)372 bool md_handle_request(struct mddev *mddev, struct bio *bio)
373 {
374 check_suspended:
375 	if (is_suspended(mddev, bio)) {
376 		DEFINE_WAIT(__wait);
377 		/* Bail out if REQ_NOWAIT is set for the bio */
378 		if (bio->bi_opf & REQ_NOWAIT) {
379 			bio_wouldblock_error(bio);
380 			return true;
381 		}
382 		for (;;) {
383 			prepare_to_wait(&mddev->sb_wait, &__wait,
384 					TASK_UNINTERRUPTIBLE);
385 			if (!is_suspended(mddev, bio))
386 				break;
387 			schedule();
388 		}
389 		finish_wait(&mddev->sb_wait, &__wait);
390 	}
391 	if (!percpu_ref_tryget_live(&mddev->active_io))
392 		goto check_suspended;
393 
394 	if (!mddev->pers->make_request(mddev, bio)) {
395 		percpu_ref_put(&mddev->active_io);
396 		if (!mddev->gendisk && mddev->pers->prepare_suspend)
397 			return false;
398 		goto check_suspended;
399 	}
400 
401 	percpu_ref_put(&mddev->active_io);
402 	return true;
403 }
404 EXPORT_SYMBOL(md_handle_request);
405 
md_submit_bio(struct bio * bio)406 static void md_submit_bio(struct bio *bio)
407 {
408 	const int rw = bio_data_dir(bio);
409 	struct mddev *mddev = bio->bi_bdev->bd_disk->private_data;
410 
411 	if (mddev == NULL || mddev->pers == NULL) {
412 		bio_io_error(bio);
413 		return;
414 	}
415 
416 	if (unlikely(test_bit(MD_BROKEN, &mddev->flags)) && (rw == WRITE)) {
417 		bio_io_error(bio);
418 		return;
419 	}
420 
421 	bio = bio_split_to_limits(bio);
422 	if (!bio)
423 		return;
424 
425 	if (mddev->ro == MD_RDONLY && unlikely(rw == WRITE)) {
426 		if (bio_sectors(bio) != 0)
427 			bio->bi_status = BLK_STS_IOERR;
428 		bio_endio(bio);
429 		return;
430 	}
431 
432 	/* bio could be mergeable after passing to underlayer */
433 	bio->bi_opf &= ~REQ_NOMERGE;
434 
435 	md_handle_request(mddev, bio);
436 }
437 
438 /*
439  * Make sure no new requests are submitted to the device, and any requests that
440  * have been submitted are completely handled.
441  */
mddev_suspend(struct mddev * mddev,bool interruptible)442 int mddev_suspend(struct mddev *mddev, bool interruptible)
443 {
444 	int err = 0;
445 
446 	/*
447 	 * hold reconfig_mutex to wait for normal io will deadlock, because
448 	 * other context can't update super_block, and normal io can rely on
449 	 * updating super_block.
450 	 */
451 	lockdep_assert_not_held(&mddev->reconfig_mutex);
452 
453 	if (interruptible)
454 		err = mutex_lock_interruptible(&mddev->suspend_mutex);
455 	else
456 		mutex_lock(&mddev->suspend_mutex);
457 	if (err)
458 		return err;
459 
460 	if (mddev->suspended) {
461 		WRITE_ONCE(mddev->suspended, mddev->suspended + 1);
462 		mutex_unlock(&mddev->suspend_mutex);
463 		return 0;
464 	}
465 
466 	percpu_ref_kill(&mddev->active_io);
467 	if (interruptible)
468 		err = wait_event_interruptible(mddev->sb_wait,
469 				percpu_ref_is_zero(&mddev->active_io));
470 	else
471 		wait_event(mddev->sb_wait,
472 				percpu_ref_is_zero(&mddev->active_io));
473 	if (err) {
474 		percpu_ref_resurrect(&mddev->active_io);
475 		mutex_unlock(&mddev->suspend_mutex);
476 		return err;
477 	}
478 
479 	/*
480 	 * For raid456, io might be waiting for reshape to make progress,
481 	 * allow new reshape to start while waiting for io to be done to
482 	 * prevent deadlock.
483 	 */
484 	WRITE_ONCE(mddev->suspended, mddev->suspended + 1);
485 
486 	/* restrict memory reclaim I/O during raid array is suspend */
487 	mddev->noio_flag = memalloc_noio_save();
488 
489 	mutex_unlock(&mddev->suspend_mutex);
490 	return 0;
491 }
492 EXPORT_SYMBOL_GPL(mddev_suspend);
493 
__mddev_resume(struct mddev * mddev,bool recovery_needed)494 static void __mddev_resume(struct mddev *mddev, bool recovery_needed)
495 {
496 	lockdep_assert_not_held(&mddev->reconfig_mutex);
497 
498 	mutex_lock(&mddev->suspend_mutex);
499 	WRITE_ONCE(mddev->suspended, mddev->suspended - 1);
500 	if (mddev->suspended) {
501 		mutex_unlock(&mddev->suspend_mutex);
502 		return;
503 	}
504 
505 	/* entred the memalloc scope from mddev_suspend() */
506 	memalloc_noio_restore(mddev->noio_flag);
507 
508 	percpu_ref_resurrect(&mddev->active_io);
509 	wake_up(&mddev->sb_wait);
510 
511 	if (recovery_needed)
512 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
513 	md_wakeup_thread(mddev->thread);
514 	md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
515 
516 	mutex_unlock(&mddev->suspend_mutex);
517 }
518 
mddev_resume(struct mddev * mddev)519 void mddev_resume(struct mddev *mddev)
520 {
521 	return __mddev_resume(mddev, true);
522 }
523 EXPORT_SYMBOL_GPL(mddev_resume);
524 
525 /* sync bdev before setting device to readonly or stopping raid*/
mddev_set_closing_and_sync_blockdev(struct mddev * mddev,int opener_num)526 static int mddev_set_closing_and_sync_blockdev(struct mddev *mddev, int opener_num)
527 {
528 	mutex_lock(&mddev->open_mutex);
529 	if (mddev->pers && atomic_read(&mddev->openers) > opener_num) {
530 		mutex_unlock(&mddev->open_mutex);
531 		return -EBUSY;
532 	}
533 	if (test_and_set_bit(MD_CLOSING, &mddev->flags)) {
534 		mutex_unlock(&mddev->open_mutex);
535 		return -EBUSY;
536 	}
537 	mutex_unlock(&mddev->open_mutex);
538 
539 	sync_blockdev(mddev->gendisk->part0);
540 	return 0;
541 }
542 
543 /*
544  * The only difference from bio_chain_endio() is that the current
545  * bi_status of bio does not affect the bi_status of parent.
546  */
md_end_flush(struct bio * bio)547 static void md_end_flush(struct bio *bio)
548 {
549 	struct bio *parent = bio->bi_private;
550 
551 	/*
552 	 * If any flush io error before the power failure,
553 	 * disk data may be lost.
554 	 */
555 	if (bio->bi_status)
556 		pr_err("md: %pg flush io error %d\n", bio->bi_bdev,
557 			blk_status_to_errno(bio->bi_status));
558 
559 	bio_put(bio);
560 	bio_endio(parent);
561 }
562 
md_flush_request(struct mddev * mddev,struct bio * bio)563 bool md_flush_request(struct mddev *mddev, struct bio *bio)
564 {
565 	struct md_rdev *rdev;
566 	struct bio *new;
567 
568 	/*
569 	 * md_flush_reqeust() should be called under md_handle_request() and
570 	 * 'active_io' is already grabbed. Hence it's safe to get rdev directly
571 	 * without rcu protection.
572 	 */
573 	WARN_ON(percpu_ref_is_zero(&mddev->active_io));
574 
575 	rdev_for_each(rdev, mddev) {
576 		if (rdev->raid_disk < 0 || test_bit(Faulty, &rdev->flags))
577 			continue;
578 
579 		new = bio_alloc_bioset(rdev->bdev, 0,
580 				       REQ_OP_WRITE | REQ_PREFLUSH, GFP_NOIO,
581 				       &mddev->bio_set);
582 		new->bi_private = bio;
583 		new->bi_end_io = md_end_flush;
584 		bio_inc_remaining(bio);
585 		submit_bio(new);
586 	}
587 
588 	if (bio_sectors(bio) == 0) {
589 		bio_endio(bio);
590 		return true;
591 	}
592 
593 	bio->bi_opf &= ~REQ_PREFLUSH;
594 	return false;
595 }
596 EXPORT_SYMBOL(md_flush_request);
597 
mddev_get(struct mddev * mddev)598 static inline struct mddev *mddev_get(struct mddev *mddev)
599 {
600 	lockdep_assert_held(&all_mddevs_lock);
601 
602 	if (test_bit(MD_DELETED, &mddev->flags))
603 		return NULL;
604 	atomic_inc(&mddev->active);
605 	return mddev;
606 }
607 
608 static void mddev_delayed_delete(struct work_struct *ws);
609 
__mddev_put(struct mddev * mddev)610 static void __mddev_put(struct mddev *mddev)
611 {
612 	if (mddev->raid_disks || !list_empty(&mddev->disks) ||
613 	    mddev->ctime || mddev->hold_active)
614 		return;
615 
616 	/* Array is not configured at all, and not held active, so destroy it */
617 	set_bit(MD_DELETED, &mddev->flags);
618 
619 	/*
620 	 * Call queue_work inside the spinlock so that flush_workqueue() after
621 	 * mddev_find will succeed in waiting for the work to be done.
622 	 */
623 	queue_work(md_misc_wq, &mddev->del_work);
624 }
625 
mddev_put_locked(struct mddev * mddev)626 static void mddev_put_locked(struct mddev *mddev)
627 {
628 	if (atomic_dec_and_test(&mddev->active))
629 		__mddev_put(mddev);
630 }
631 
mddev_put(struct mddev * mddev)632 void mddev_put(struct mddev *mddev)
633 {
634 	if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
635 		return;
636 
637 	__mddev_put(mddev);
638 	spin_unlock(&all_mddevs_lock);
639 }
640 
641 static void md_safemode_timeout(struct timer_list *t);
642 static void md_start_sync(struct work_struct *ws);
643 
active_io_release(struct percpu_ref * ref)644 static void active_io_release(struct percpu_ref *ref)
645 {
646 	struct mddev *mddev = container_of(ref, struct mddev, active_io);
647 
648 	wake_up(&mddev->sb_wait);
649 }
650 
no_op(struct percpu_ref * r)651 static void no_op(struct percpu_ref *r) {}
652 
mddev_init(struct mddev * mddev)653 int mddev_init(struct mddev *mddev)
654 {
655 
656 	if (percpu_ref_init(&mddev->active_io, active_io_release,
657 			    PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
658 		return -ENOMEM;
659 
660 	if (percpu_ref_init(&mddev->writes_pending, no_op,
661 			    PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
662 		percpu_ref_exit(&mddev->active_io);
663 		return -ENOMEM;
664 	}
665 
666 	/* We want to start with the refcount at zero */
667 	percpu_ref_put(&mddev->writes_pending);
668 
669 	mutex_init(&mddev->open_mutex);
670 	mutex_init(&mddev->reconfig_mutex);
671 	mutex_init(&mddev->suspend_mutex);
672 	mutex_init(&mddev->bitmap_info.mutex);
673 	INIT_LIST_HEAD(&mddev->disks);
674 	INIT_LIST_HEAD(&mddev->all_mddevs);
675 	INIT_LIST_HEAD(&mddev->deleting);
676 	timer_setup(&mddev->safemode_timer, md_safemode_timeout, 0);
677 	atomic_set(&mddev->active, 1);
678 	atomic_set(&mddev->openers, 0);
679 	atomic_set(&mddev->sync_seq, 0);
680 	spin_lock_init(&mddev->lock);
681 	init_waitqueue_head(&mddev->sb_wait);
682 	init_waitqueue_head(&mddev->recovery_wait);
683 	mddev->reshape_position = MaxSector;
684 	mddev->reshape_backwards = 0;
685 	mddev->last_sync_action = ACTION_IDLE;
686 	mddev->resync_min = 0;
687 	mddev->resync_max = MaxSector;
688 	mddev->level = LEVEL_NONE;
689 	mddev_set_bitmap_ops(mddev);
690 
691 	INIT_WORK(&mddev->sync_work, md_start_sync);
692 	INIT_WORK(&mddev->del_work, mddev_delayed_delete);
693 
694 	return 0;
695 }
696 EXPORT_SYMBOL_GPL(mddev_init);
697 
mddev_destroy(struct mddev * mddev)698 void mddev_destroy(struct mddev *mddev)
699 {
700 	percpu_ref_exit(&mddev->active_io);
701 	percpu_ref_exit(&mddev->writes_pending);
702 }
703 EXPORT_SYMBOL_GPL(mddev_destroy);
704 
mddev_find_locked(dev_t unit)705 static struct mddev *mddev_find_locked(dev_t unit)
706 {
707 	struct mddev *mddev;
708 
709 	list_for_each_entry(mddev, &all_mddevs, all_mddevs)
710 		if (mddev->unit == unit)
711 			return mddev;
712 
713 	return NULL;
714 }
715 
716 /* find an unused unit number */
mddev_alloc_unit(void)717 static dev_t mddev_alloc_unit(void)
718 {
719 	static int next_minor = 512;
720 	int start = next_minor;
721 	bool is_free = 0;
722 	dev_t dev = 0;
723 
724 	while (!is_free) {
725 		dev = MKDEV(MD_MAJOR, next_minor);
726 		next_minor++;
727 		if (next_minor > MINORMASK)
728 			next_minor = 0;
729 		if (next_minor == start)
730 			return 0;		/* Oh dear, all in use. */
731 		is_free = !mddev_find_locked(dev);
732 	}
733 
734 	return dev;
735 }
736 
mddev_alloc(dev_t unit)737 static struct mddev *mddev_alloc(dev_t unit)
738 {
739 	struct mddev *new;
740 	int error;
741 
742 	if (unit && MAJOR(unit) != MD_MAJOR)
743 		unit &= ~((1 << MdpMinorShift) - 1);
744 
745 	new = kzalloc(sizeof(*new), GFP_KERNEL);
746 	if (!new)
747 		return ERR_PTR(-ENOMEM);
748 
749 	error = mddev_init(new);
750 	if (error)
751 		goto out_free_new;
752 
753 	spin_lock(&all_mddevs_lock);
754 	if (unit) {
755 		error = -EEXIST;
756 		if (mddev_find_locked(unit))
757 			goto out_destroy_new;
758 		new->unit = unit;
759 		if (MAJOR(unit) == MD_MAJOR)
760 			new->md_minor = MINOR(unit);
761 		else
762 			new->md_minor = MINOR(unit) >> MdpMinorShift;
763 		new->hold_active = UNTIL_IOCTL;
764 	} else {
765 		error = -ENODEV;
766 		new->unit = mddev_alloc_unit();
767 		if (!new->unit)
768 			goto out_destroy_new;
769 		new->md_minor = MINOR(new->unit);
770 		new->hold_active = UNTIL_STOP;
771 	}
772 
773 	list_add(&new->all_mddevs, &all_mddevs);
774 	spin_unlock(&all_mddevs_lock);
775 	return new;
776 
777 out_destroy_new:
778 	spin_unlock(&all_mddevs_lock);
779 	mddev_destroy(new);
780 out_free_new:
781 	kfree(new);
782 	return ERR_PTR(error);
783 }
784 
mddev_free(struct mddev * mddev)785 static void mddev_free(struct mddev *mddev)
786 {
787 	spin_lock(&all_mddevs_lock);
788 	list_del(&mddev->all_mddevs);
789 	spin_unlock(&all_mddevs_lock);
790 
791 	mddev_destroy(mddev);
792 	kfree(mddev);
793 }
794 
795 static const struct attribute_group md_redundancy_group;
796 
mddev_unlock(struct mddev * mddev)797 void mddev_unlock(struct mddev *mddev)
798 {
799 	struct md_rdev *rdev;
800 	struct md_rdev *tmp;
801 	LIST_HEAD(delete);
802 
803 	if (!list_empty(&mddev->deleting))
804 		list_splice_init(&mddev->deleting, &delete);
805 
806 	if (mddev->to_remove) {
807 		/* These cannot be removed under reconfig_mutex as
808 		 * an access to the files will try to take reconfig_mutex
809 		 * while holding the file unremovable, which leads to
810 		 * a deadlock.
811 		 * So hold set sysfs_active while the remove in happeing,
812 		 * and anything else which might set ->to_remove or my
813 		 * otherwise change the sysfs namespace will fail with
814 		 * -EBUSY if sysfs_active is still set.
815 		 * We set sysfs_active under reconfig_mutex and elsewhere
816 		 * test it under the same mutex to ensure its correct value
817 		 * is seen.
818 		 */
819 		const struct attribute_group *to_remove = mddev->to_remove;
820 		mddev->to_remove = NULL;
821 		mddev->sysfs_active = 1;
822 		mutex_unlock(&mddev->reconfig_mutex);
823 
824 		if (mddev->kobj.sd) {
825 			if (to_remove != &md_redundancy_group)
826 				sysfs_remove_group(&mddev->kobj, to_remove);
827 			if (mddev->pers == NULL ||
828 			    mddev->pers->sync_request == NULL) {
829 				sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
830 				if (mddev->sysfs_action)
831 					sysfs_put(mddev->sysfs_action);
832 				if (mddev->sysfs_completed)
833 					sysfs_put(mddev->sysfs_completed);
834 				if (mddev->sysfs_degraded)
835 					sysfs_put(mddev->sysfs_degraded);
836 				mddev->sysfs_action = NULL;
837 				mddev->sysfs_completed = NULL;
838 				mddev->sysfs_degraded = NULL;
839 			}
840 		}
841 		mddev->sysfs_active = 0;
842 	} else
843 		mutex_unlock(&mddev->reconfig_mutex);
844 
845 	md_wakeup_thread(mddev->thread);
846 	wake_up(&mddev->sb_wait);
847 
848 	list_for_each_entry_safe(rdev, tmp, &delete, same_set) {
849 		list_del_init(&rdev->same_set);
850 		kobject_del(&rdev->kobj);
851 		export_rdev(rdev, mddev);
852 	}
853 }
854 EXPORT_SYMBOL_GPL(mddev_unlock);
855 
md_find_rdev_nr_rcu(struct mddev * mddev,int nr)856 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr)
857 {
858 	struct md_rdev *rdev;
859 
860 	rdev_for_each_rcu(rdev, mddev)
861 		if (rdev->desc_nr == nr)
862 			return rdev;
863 
864 	return NULL;
865 }
866 EXPORT_SYMBOL_GPL(md_find_rdev_nr_rcu);
867 
find_rdev(struct mddev * mddev,dev_t dev)868 static struct md_rdev *find_rdev(struct mddev *mddev, dev_t dev)
869 {
870 	struct md_rdev *rdev;
871 
872 	rdev_for_each(rdev, mddev)
873 		if (rdev->bdev->bd_dev == dev)
874 			return rdev;
875 
876 	return NULL;
877 }
878 
md_find_rdev_rcu(struct mddev * mddev,dev_t dev)879 struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev)
880 {
881 	struct md_rdev *rdev;
882 
883 	rdev_for_each_rcu(rdev, mddev)
884 		if (rdev->bdev->bd_dev == dev)
885 			return rdev;
886 
887 	return NULL;
888 }
889 EXPORT_SYMBOL_GPL(md_find_rdev_rcu);
890 
get_pers(int level,char * clevel)891 static struct md_personality *get_pers(int level, char *clevel)
892 {
893 	struct md_personality *ret = NULL;
894 	struct md_submodule_head *head;
895 	unsigned long i;
896 
897 	xa_lock(&md_submodule);
898 	xa_for_each(&md_submodule, i, head) {
899 		if (head->type != MD_PERSONALITY)
900 			continue;
901 		if ((level != LEVEL_NONE && head->id == level) ||
902 		    !strcmp(head->name, clevel)) {
903 			if (try_module_get(head->owner))
904 				ret = (void *)head;
905 			break;
906 		}
907 	}
908 	xa_unlock(&md_submodule);
909 
910 	if (!ret) {
911 		if (level != LEVEL_NONE)
912 			pr_warn("md: personality for level %d is not loaded!\n",
913 				level);
914 		else
915 			pr_warn("md: personality for level %s is not loaded!\n",
916 				clevel);
917 	}
918 
919 	return ret;
920 }
921 
put_pers(struct md_personality * pers)922 static void put_pers(struct md_personality *pers)
923 {
924 	module_put(pers->head.owner);
925 }
926 
927 /* return the offset of the super block in 512byte sectors */
calc_dev_sboffset(struct md_rdev * rdev)928 static inline sector_t calc_dev_sboffset(struct md_rdev *rdev)
929 {
930 	return MD_NEW_SIZE_SECTORS(bdev_nr_sectors(rdev->bdev));
931 }
932 
alloc_disk_sb(struct md_rdev * rdev)933 static int alloc_disk_sb(struct md_rdev *rdev)
934 {
935 	rdev->sb_page = alloc_page(GFP_KERNEL);
936 	if (!rdev->sb_page)
937 		return -ENOMEM;
938 	return 0;
939 }
940 
md_rdev_clear(struct md_rdev * rdev)941 void md_rdev_clear(struct md_rdev *rdev)
942 {
943 	if (rdev->sb_page) {
944 		put_page(rdev->sb_page);
945 		rdev->sb_loaded = 0;
946 		rdev->sb_page = NULL;
947 		rdev->sb_start = 0;
948 		rdev->sectors = 0;
949 	}
950 	if (rdev->bb_page) {
951 		put_page(rdev->bb_page);
952 		rdev->bb_page = NULL;
953 	}
954 	badblocks_exit(&rdev->badblocks);
955 }
956 EXPORT_SYMBOL_GPL(md_rdev_clear);
957 
super_written(struct bio * bio)958 static void super_written(struct bio *bio)
959 {
960 	struct md_rdev *rdev = bio->bi_private;
961 	struct mddev *mddev = rdev->mddev;
962 
963 	if (bio->bi_status) {
964 		pr_err("md: %s gets error=%d\n", __func__,
965 		       blk_status_to_errno(bio->bi_status));
966 		md_error(mddev, rdev);
967 		if (!test_bit(Faulty, &rdev->flags)
968 		    && (bio->bi_opf & MD_FAILFAST)) {
969 			set_bit(MD_SB_NEED_REWRITE, &mddev->sb_flags);
970 			set_bit(LastDev, &rdev->flags);
971 		}
972 	} else
973 		clear_bit(LastDev, &rdev->flags);
974 
975 	bio_put(bio);
976 
977 	rdev_dec_pending(rdev, mddev);
978 
979 	if (atomic_dec_and_test(&mddev->pending_writes))
980 		wake_up(&mddev->sb_wait);
981 }
982 
md_super_write(struct mddev * mddev,struct md_rdev * rdev,sector_t sector,int size,struct page * page)983 void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
984 		   sector_t sector, int size, struct page *page)
985 {
986 	/* write first size bytes of page to sector of rdev
987 	 * Increment mddev->pending_writes before returning
988 	 * and decrement it on completion, waking up sb_wait
989 	 * if zero is reached.
990 	 * If an error occurred, call md_error
991 	 */
992 	struct bio *bio;
993 
994 	if (!page)
995 		return;
996 
997 	if (test_bit(Faulty, &rdev->flags))
998 		return;
999 
1000 	bio = bio_alloc_bioset(rdev->meta_bdev ? rdev->meta_bdev : rdev->bdev,
1001 			      1,
1002 			      REQ_OP_WRITE | REQ_SYNC | REQ_IDLE | REQ_META
1003 				  | REQ_PREFLUSH | REQ_FUA,
1004 			      GFP_NOIO, &mddev->sync_set);
1005 
1006 	atomic_inc(&rdev->nr_pending);
1007 
1008 	bio->bi_iter.bi_sector = sector;
1009 	__bio_add_page(bio, page, size, 0);
1010 	bio->bi_private = rdev;
1011 	bio->bi_end_io = super_written;
1012 
1013 	if (test_bit(MD_FAILFAST_SUPPORTED, &mddev->flags) &&
1014 	    test_bit(FailFast, &rdev->flags) &&
1015 	    !test_bit(LastDev, &rdev->flags))
1016 		bio->bi_opf |= MD_FAILFAST;
1017 
1018 	atomic_inc(&mddev->pending_writes);
1019 	submit_bio(bio);
1020 }
1021 
md_super_wait(struct mddev * mddev)1022 int md_super_wait(struct mddev *mddev)
1023 {
1024 	/* wait for all superblock writes that were scheduled to complete */
1025 	wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
1026 	if (test_and_clear_bit(MD_SB_NEED_REWRITE, &mddev->sb_flags))
1027 		return -EAGAIN;
1028 	return 0;
1029 }
1030 
sync_page_io(struct md_rdev * rdev,sector_t sector,int size,struct page * page,blk_opf_t opf,bool metadata_op)1031 int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
1032 		 struct page *page, blk_opf_t opf, bool metadata_op)
1033 {
1034 	struct bio bio;
1035 	struct bio_vec bvec;
1036 
1037 	if (metadata_op && rdev->meta_bdev)
1038 		bio_init(&bio, rdev->meta_bdev, &bvec, 1, opf);
1039 	else
1040 		bio_init(&bio, rdev->bdev, &bvec, 1, opf);
1041 
1042 	if (metadata_op)
1043 		bio.bi_iter.bi_sector = sector + rdev->sb_start;
1044 	else if (rdev->mddev->reshape_position != MaxSector &&
1045 		 (rdev->mddev->reshape_backwards ==
1046 		  (sector >= rdev->mddev->reshape_position)))
1047 		bio.bi_iter.bi_sector = sector + rdev->new_data_offset;
1048 	else
1049 		bio.bi_iter.bi_sector = sector + rdev->data_offset;
1050 	__bio_add_page(&bio, page, size, 0);
1051 
1052 	submit_bio_wait(&bio);
1053 
1054 	return !bio.bi_status;
1055 }
1056 EXPORT_SYMBOL_GPL(sync_page_io);
1057 
read_disk_sb(struct md_rdev * rdev,int size)1058 static int read_disk_sb(struct md_rdev *rdev, int size)
1059 {
1060 	if (rdev->sb_loaded)
1061 		return 0;
1062 
1063 	if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, true))
1064 		goto fail;
1065 	rdev->sb_loaded = 1;
1066 	return 0;
1067 
1068 fail:
1069 	pr_err("md: disabled device %pg, could not read superblock.\n",
1070 	       rdev->bdev);
1071 	return -EINVAL;
1072 }
1073 
md_uuid_equal(mdp_super_t * sb1,mdp_super_t * sb2)1074 static int md_uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
1075 {
1076 	return	sb1->set_uuid0 == sb2->set_uuid0 &&
1077 		sb1->set_uuid1 == sb2->set_uuid1 &&
1078 		sb1->set_uuid2 == sb2->set_uuid2 &&
1079 		sb1->set_uuid3 == sb2->set_uuid3;
1080 }
1081 
md_sb_equal(mdp_super_t * sb1,mdp_super_t * sb2)1082 static int md_sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
1083 {
1084 	int ret;
1085 	mdp_super_t *tmp1, *tmp2;
1086 
1087 	tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
1088 	tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
1089 
1090 	if (!tmp1 || !tmp2) {
1091 		ret = 0;
1092 		goto abort;
1093 	}
1094 
1095 	*tmp1 = *sb1;
1096 	*tmp2 = *sb2;
1097 
1098 	/*
1099 	 * nr_disks is not constant
1100 	 */
1101 	tmp1->nr_disks = 0;
1102 	tmp2->nr_disks = 0;
1103 
1104 	ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
1105 abort:
1106 	kfree(tmp1);
1107 	kfree(tmp2);
1108 	return ret;
1109 }
1110 
md_csum_fold(u32 csum)1111 static u32 md_csum_fold(u32 csum)
1112 {
1113 	csum = (csum & 0xffff) + (csum >> 16);
1114 	return (csum & 0xffff) + (csum >> 16);
1115 }
1116 
calc_sb_csum(mdp_super_t * sb)1117 static unsigned int calc_sb_csum(mdp_super_t *sb)
1118 {
1119 	u64 newcsum = 0;
1120 	u32 *sb32 = (u32*)sb;
1121 	int i;
1122 	unsigned int disk_csum, csum;
1123 
1124 	disk_csum = sb->sb_csum;
1125 	sb->sb_csum = 0;
1126 
1127 	for (i = 0; i < MD_SB_BYTES/4 ; i++)
1128 		newcsum += sb32[i];
1129 	csum = (newcsum & 0xffffffff) + (newcsum>>32);
1130 
1131 #ifdef CONFIG_ALPHA
1132 	/* This used to use csum_partial, which was wrong for several
1133 	 * reasons including that different results are returned on
1134 	 * different architectures.  It isn't critical that we get exactly
1135 	 * the same return value as before (we always csum_fold before
1136 	 * testing, and that removes any differences).  However as we
1137 	 * know that csum_partial always returned a 16bit value on
1138 	 * alphas, do a fold to maximise conformity to previous behaviour.
1139 	 */
1140 	sb->sb_csum = md_csum_fold(disk_csum);
1141 #else
1142 	sb->sb_csum = disk_csum;
1143 #endif
1144 	return csum;
1145 }
1146 
1147 /*
1148  * Handle superblock details.
1149  * We want to be able to handle multiple superblock formats
1150  * so we have a common interface to them all, and an array of
1151  * different handlers.
1152  * We rely on user-space to write the initial superblock, and support
1153  * reading and updating of superblocks.
1154  * Interface methods are:
1155  *   int load_super(struct md_rdev *dev, struct md_rdev *refdev, int minor_version)
1156  *      loads and validates a superblock on dev.
1157  *      if refdev != NULL, compare superblocks on both devices
1158  *    Return:
1159  *      0 - dev has a superblock that is compatible with refdev
1160  *      1 - dev has a superblock that is compatible and newer than refdev
1161  *          so dev should be used as the refdev in future
1162  *     -EINVAL superblock incompatible or invalid
1163  *     -othererror e.g. -EIO
1164  *
1165  *   int validate_super(struct mddev *mddev, struct md_rdev *dev)
1166  *      Verify that dev is acceptable into mddev.
1167  *       The first time, mddev->raid_disks will be 0, and data from
1168  *       dev should be merged in.  Subsequent calls check that dev
1169  *       is new enough.  Return 0 or -EINVAL
1170  *
1171  *   void sync_super(struct mddev *mddev, struct md_rdev *dev)
1172  *     Update the superblock for rdev with data in mddev
1173  *     This does not write to disc.
1174  *
1175  */
1176 
1177 struct super_type  {
1178 	char		    *name;
1179 	struct module	    *owner;
1180 	int		    (*load_super)(struct md_rdev *rdev,
1181 					  struct md_rdev *refdev,
1182 					  int minor_version);
1183 	int		    (*validate_super)(struct mddev *mddev,
1184 					      struct md_rdev *freshest,
1185 					      struct md_rdev *rdev);
1186 	void		    (*sync_super)(struct mddev *mddev,
1187 					  struct md_rdev *rdev);
1188 	unsigned long long  (*rdev_size_change)(struct md_rdev *rdev,
1189 						sector_t num_sectors);
1190 	int		    (*allow_new_offset)(struct md_rdev *rdev,
1191 						unsigned long long new_offset);
1192 };
1193 
1194 /*
1195  * Check that the given mddev has no bitmap.
1196  *
1197  * This function is called from the run method of all personalities that do not
1198  * support bitmaps. It prints an error message and returns non-zero if mddev
1199  * has a bitmap. Otherwise, it returns 0.
1200  *
1201  */
md_check_no_bitmap(struct mddev * mddev)1202 int md_check_no_bitmap(struct mddev *mddev)
1203 {
1204 	if (!mddev->bitmap_info.file && !mddev->bitmap_info.offset)
1205 		return 0;
1206 	pr_warn("%s: bitmaps are not supported for %s\n",
1207 		mdname(mddev), mddev->pers->head.name);
1208 	return 1;
1209 }
1210 EXPORT_SYMBOL(md_check_no_bitmap);
1211 
1212 /*
1213  * load_super for 0.90.0
1214  */
super_90_load(struct md_rdev * rdev,struct md_rdev * refdev,int minor_version)1215 static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1216 {
1217 	mdp_super_t *sb;
1218 	int ret;
1219 	bool spare_disk = true;
1220 
1221 	/*
1222 	 * Calculate the position of the superblock (512byte sectors),
1223 	 * it's at the end of the disk.
1224 	 *
1225 	 * It also happens to be a multiple of 4Kb.
1226 	 */
1227 	rdev->sb_start = calc_dev_sboffset(rdev);
1228 
1229 	ret = read_disk_sb(rdev, MD_SB_BYTES);
1230 	if (ret)
1231 		return ret;
1232 
1233 	ret = -EINVAL;
1234 
1235 	sb = page_address(rdev->sb_page);
1236 
1237 	if (sb->md_magic != MD_SB_MAGIC) {
1238 		pr_warn("md: invalid raid superblock magic on %pg\n",
1239 			rdev->bdev);
1240 		goto abort;
1241 	}
1242 
1243 	if (sb->major_version != 0 ||
1244 	    sb->minor_version < 90 ||
1245 	    sb->minor_version > 91) {
1246 		pr_warn("Bad version number %d.%d on %pg\n",
1247 			sb->major_version, sb->minor_version, rdev->bdev);
1248 		goto abort;
1249 	}
1250 
1251 	if (sb->raid_disks <= 0)
1252 		goto abort;
1253 
1254 	if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
1255 		pr_warn("md: invalid superblock checksum on %pg\n", rdev->bdev);
1256 		goto abort;
1257 	}
1258 
1259 	rdev->preferred_minor = sb->md_minor;
1260 	rdev->data_offset = 0;
1261 	rdev->new_data_offset = 0;
1262 	rdev->sb_size = MD_SB_BYTES;
1263 	rdev->badblocks.shift = -1;
1264 
1265 	rdev->desc_nr = sb->this_disk.number;
1266 
1267 	/* not spare disk */
1268 	if (rdev->desc_nr >= 0 && rdev->desc_nr < MD_SB_DISKS &&
1269 	    sb->disks[rdev->desc_nr].state & ((1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))
1270 		spare_disk = false;
1271 
1272 	if (!refdev) {
1273 		if (!spare_disk)
1274 			ret = 1;
1275 		else
1276 			ret = 0;
1277 	} else {
1278 		__u64 ev1, ev2;
1279 		mdp_super_t *refsb = page_address(refdev->sb_page);
1280 		if (!md_uuid_equal(refsb, sb)) {
1281 			pr_warn("md: %pg has different UUID to %pg\n",
1282 				rdev->bdev, refdev->bdev);
1283 			goto abort;
1284 		}
1285 		if (!md_sb_equal(refsb, sb)) {
1286 			pr_warn("md: %pg has same UUID but different superblock to %pg\n",
1287 				rdev->bdev, refdev->bdev);
1288 			goto abort;
1289 		}
1290 		ev1 = md_event(sb);
1291 		ev2 = md_event(refsb);
1292 
1293 		if (!spare_disk && ev1 > ev2)
1294 			ret = 1;
1295 		else
1296 			ret = 0;
1297 	}
1298 	rdev->sectors = rdev->sb_start;
1299 	/* Limit to 4TB as metadata cannot record more than that.
1300 	 * (not needed for Linear and RAID0 as metadata doesn't
1301 	 * record this size)
1302 	 */
1303 	if ((u64)rdev->sectors >= (2ULL << 32) && sb->level >= 1)
1304 		rdev->sectors = (sector_t)(2ULL << 32) - 2;
1305 
1306 	if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1)
1307 		/* "this cannot possibly happen" ... */
1308 		ret = -EINVAL;
1309 
1310  abort:
1311 	return ret;
1312 }
1313 
md_bitmap_events_cleared(struct mddev * mddev)1314 static u64 md_bitmap_events_cleared(struct mddev *mddev)
1315 {
1316 	struct md_bitmap_stats stats;
1317 	int err;
1318 
1319 	err = mddev->bitmap_ops->get_stats(mddev->bitmap, &stats);
1320 	if (err)
1321 		return 0;
1322 
1323 	return stats.events_cleared;
1324 }
1325 
1326 /*
1327  * validate_super for 0.90.0
1328  * note: we are not using "freshest" for 0.9 superblock
1329  */
super_90_validate(struct mddev * mddev,struct md_rdev * freshest,struct md_rdev * rdev)1330 static int super_90_validate(struct mddev *mddev, struct md_rdev *freshest, struct md_rdev *rdev)
1331 {
1332 	mdp_disk_t *desc;
1333 	mdp_super_t *sb = page_address(rdev->sb_page);
1334 	__u64 ev1 = md_event(sb);
1335 
1336 	rdev->raid_disk = -1;
1337 	clear_bit(Faulty, &rdev->flags);
1338 	clear_bit(In_sync, &rdev->flags);
1339 	clear_bit(Bitmap_sync, &rdev->flags);
1340 	clear_bit(WriteMostly, &rdev->flags);
1341 
1342 	if (mddev->raid_disks == 0) {
1343 		mddev->major_version = 0;
1344 		mddev->minor_version = sb->minor_version;
1345 		mddev->patch_version = sb->patch_version;
1346 		mddev->external = 0;
1347 		mddev->chunk_sectors = sb->chunk_size >> 9;
1348 		mddev->ctime = sb->ctime;
1349 		mddev->utime = sb->utime;
1350 		mddev->level = sb->level;
1351 		mddev->clevel[0] = 0;
1352 		mddev->layout = sb->layout;
1353 		mddev->raid_disks = sb->raid_disks;
1354 		mddev->dev_sectors = ((sector_t)sb->size) * 2;
1355 		mddev->events = ev1;
1356 		mddev->bitmap_info.offset = 0;
1357 		mddev->bitmap_info.space = 0;
1358 		/* bitmap can use 60 K after the 4K superblocks */
1359 		mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
1360 		mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
1361 		mddev->reshape_backwards = 0;
1362 
1363 		if (mddev->minor_version >= 91) {
1364 			mddev->reshape_position = sb->reshape_position;
1365 			mddev->delta_disks = sb->delta_disks;
1366 			mddev->new_level = sb->new_level;
1367 			mddev->new_layout = sb->new_layout;
1368 			mddev->new_chunk_sectors = sb->new_chunk >> 9;
1369 			if (mddev->delta_disks < 0)
1370 				mddev->reshape_backwards = 1;
1371 		} else {
1372 			mddev->reshape_position = MaxSector;
1373 			mddev->delta_disks = 0;
1374 			mddev->new_level = mddev->level;
1375 			mddev->new_layout = mddev->layout;
1376 			mddev->new_chunk_sectors = mddev->chunk_sectors;
1377 		}
1378 		if (mddev->level == 0)
1379 			mddev->layout = -1;
1380 
1381 		if (sb->state & (1<<MD_SB_CLEAN))
1382 			mddev->recovery_cp = MaxSector;
1383 		else {
1384 			if (sb->events_hi == sb->cp_events_hi &&
1385 				sb->events_lo == sb->cp_events_lo) {
1386 				mddev->recovery_cp = sb->recovery_cp;
1387 			} else
1388 				mddev->recovery_cp = 0;
1389 		}
1390 
1391 		memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
1392 		memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
1393 		memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
1394 		memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
1395 
1396 		mddev->max_disks = MD_SB_DISKS;
1397 
1398 		if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
1399 		    mddev->bitmap_info.file == NULL) {
1400 			mddev->bitmap_info.offset =
1401 				mddev->bitmap_info.default_offset;
1402 			mddev->bitmap_info.space =
1403 				mddev->bitmap_info.default_space;
1404 		}
1405 
1406 	} else if (mddev->pers == NULL) {
1407 		/* Insist on good event counter while assembling, except
1408 		 * for spares (which don't need an event count) */
1409 		++ev1;
1410 		if (sb->disks[rdev->desc_nr].state & (
1411 			    (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))
1412 			if (ev1 < mddev->events)
1413 				return -EINVAL;
1414 	} else if (mddev->bitmap) {
1415 		/* if adding to array with a bitmap, then we can accept an
1416 		 * older device ... but not too old.
1417 		 */
1418 		if (ev1 < md_bitmap_events_cleared(mddev))
1419 			return 0;
1420 		if (ev1 < mddev->events)
1421 			set_bit(Bitmap_sync, &rdev->flags);
1422 	} else {
1423 		if (ev1 < mddev->events)
1424 			/* just a hot-add of a new device, leave raid_disk at -1 */
1425 			return 0;
1426 	}
1427 
1428 	desc = sb->disks + rdev->desc_nr;
1429 
1430 	if (desc->state & (1<<MD_DISK_FAULTY))
1431 		set_bit(Faulty, &rdev->flags);
1432 	else if (desc->state & (1<<MD_DISK_SYNC)) {
1433 		set_bit(In_sync, &rdev->flags);
1434 		rdev->raid_disk = desc->raid_disk;
1435 		rdev->saved_raid_disk = desc->raid_disk;
1436 	} else if (desc->state & (1<<MD_DISK_ACTIVE)) {
1437 		/* active but not in sync implies recovery up to
1438 		 * reshape position.  We don't know exactly where
1439 		 * that is, so set to zero for now
1440 		 */
1441 		if (mddev->minor_version >= 91) {
1442 			rdev->recovery_offset = 0;
1443 			rdev->raid_disk = desc->raid_disk;
1444 		}
1445 	}
1446 	if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
1447 		set_bit(WriteMostly, &rdev->flags);
1448 	if (desc->state & (1<<MD_DISK_FAILFAST))
1449 		set_bit(FailFast, &rdev->flags);
1450 	return 0;
1451 }
1452 
1453 /*
1454  * sync_super for 0.90.0
1455  */
super_90_sync(struct mddev * mddev,struct md_rdev * rdev)1456 static void super_90_sync(struct mddev *mddev, struct md_rdev *rdev)
1457 {
1458 	mdp_super_t *sb;
1459 	struct md_rdev *rdev2;
1460 	int next_spare = mddev->raid_disks;
1461 
1462 	/* make rdev->sb match mddev data..
1463 	 *
1464 	 * 1/ zero out disks
1465 	 * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
1466 	 * 3/ any empty disks < next_spare become removed
1467 	 *
1468 	 * disks[0] gets initialised to REMOVED because
1469 	 * we cannot be sure from other fields if it has
1470 	 * been initialised or not.
1471 	 */
1472 	int i;
1473 	int active=0, working=0,failed=0,spare=0,nr_disks=0;
1474 
1475 	rdev->sb_size = MD_SB_BYTES;
1476 
1477 	sb = page_address(rdev->sb_page);
1478 
1479 	memset(sb, 0, sizeof(*sb));
1480 
1481 	sb->md_magic = MD_SB_MAGIC;
1482 	sb->major_version = mddev->major_version;
1483 	sb->patch_version = mddev->patch_version;
1484 	sb->gvalid_words  = 0; /* ignored */
1485 	memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
1486 	memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
1487 	memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
1488 	memcpy(&sb->set_uuid3, mddev->uuid+12,4);
1489 
1490 	sb->ctime = clamp_t(time64_t, mddev->ctime, 0, U32_MAX);
1491 	sb->level = mddev->level;
1492 	sb->size = mddev->dev_sectors / 2;
1493 	sb->raid_disks = mddev->raid_disks;
1494 	sb->md_minor = mddev->md_minor;
1495 	sb->not_persistent = 0;
1496 	sb->utime = clamp_t(time64_t, mddev->utime, 0, U32_MAX);
1497 	sb->state = 0;
1498 	sb->events_hi = (mddev->events>>32);
1499 	sb->events_lo = (u32)mddev->events;
1500 
1501 	if (mddev->reshape_position == MaxSector)
1502 		sb->minor_version = 90;
1503 	else {
1504 		sb->minor_version = 91;
1505 		sb->reshape_position = mddev->reshape_position;
1506 		sb->new_level = mddev->new_level;
1507 		sb->delta_disks = mddev->delta_disks;
1508 		sb->new_layout = mddev->new_layout;
1509 		sb->new_chunk = mddev->new_chunk_sectors << 9;
1510 	}
1511 	mddev->minor_version = sb->minor_version;
1512 	if (mddev->in_sync)
1513 	{
1514 		sb->recovery_cp = mddev->recovery_cp;
1515 		sb->cp_events_hi = (mddev->events>>32);
1516 		sb->cp_events_lo = (u32)mddev->events;
1517 		if (mddev->recovery_cp == MaxSector)
1518 			sb->state = (1<< MD_SB_CLEAN);
1519 	} else
1520 		sb->recovery_cp = 0;
1521 
1522 	sb->layout = mddev->layout;
1523 	sb->chunk_size = mddev->chunk_sectors << 9;
1524 
1525 	if (mddev->bitmap && mddev->bitmap_info.file == NULL)
1526 		sb->state |= (1<<MD_SB_BITMAP_PRESENT);
1527 
1528 	sb->disks[0].state = (1<<MD_DISK_REMOVED);
1529 	rdev_for_each(rdev2, mddev) {
1530 		mdp_disk_t *d;
1531 		int desc_nr;
1532 		int is_active = test_bit(In_sync, &rdev2->flags);
1533 
1534 		if (rdev2->raid_disk >= 0 &&
1535 		    sb->minor_version >= 91)
1536 			/* we have nowhere to store the recovery_offset,
1537 			 * but if it is not below the reshape_position,
1538 			 * we can piggy-back on that.
1539 			 */
1540 			is_active = 1;
1541 		if (rdev2->raid_disk < 0 ||
1542 		    test_bit(Faulty, &rdev2->flags))
1543 			is_active = 0;
1544 		if (is_active)
1545 			desc_nr = rdev2->raid_disk;
1546 		else
1547 			desc_nr = next_spare++;
1548 		rdev2->desc_nr = desc_nr;
1549 		d = &sb->disks[rdev2->desc_nr];
1550 		nr_disks++;
1551 		d->number = rdev2->desc_nr;
1552 		d->major = MAJOR(rdev2->bdev->bd_dev);
1553 		d->minor = MINOR(rdev2->bdev->bd_dev);
1554 		if (is_active)
1555 			d->raid_disk = rdev2->raid_disk;
1556 		else
1557 			d->raid_disk = rdev2->desc_nr; /* compatibility */
1558 		if (test_bit(Faulty, &rdev2->flags))
1559 			d->state = (1<<MD_DISK_FAULTY);
1560 		else if (is_active) {
1561 			d->state = (1<<MD_DISK_ACTIVE);
1562 			if (test_bit(In_sync, &rdev2->flags))
1563 				d->state |= (1<<MD_DISK_SYNC);
1564 			active++;
1565 			working++;
1566 		} else {
1567 			d->state = 0;
1568 			spare++;
1569 			working++;
1570 		}
1571 		if (test_bit(WriteMostly, &rdev2->flags))
1572 			d->state |= (1<<MD_DISK_WRITEMOSTLY);
1573 		if (test_bit(FailFast, &rdev2->flags))
1574 			d->state |= (1<<MD_DISK_FAILFAST);
1575 	}
1576 	/* now set the "removed" and "faulty" bits on any missing devices */
1577 	for (i=0 ; i < mddev->raid_disks ; i++) {
1578 		mdp_disk_t *d = &sb->disks[i];
1579 		if (d->state == 0 && d->number == 0) {
1580 			d->number = i;
1581 			d->raid_disk = i;
1582 			d->state = (1<<MD_DISK_REMOVED);
1583 			d->state |= (1<<MD_DISK_FAULTY);
1584 			failed++;
1585 		}
1586 	}
1587 	sb->nr_disks = nr_disks;
1588 	sb->active_disks = active;
1589 	sb->working_disks = working;
1590 	sb->failed_disks = failed;
1591 	sb->spare_disks = spare;
1592 
1593 	sb->this_disk = sb->disks[rdev->desc_nr];
1594 	sb->sb_csum = calc_sb_csum(sb);
1595 }
1596 
1597 /*
1598  * rdev_size_change for 0.90.0
1599  */
1600 static unsigned long long
super_90_rdev_size_change(struct md_rdev * rdev,sector_t num_sectors)1601 super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1602 {
1603 	if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1604 		return 0; /* component must fit device */
1605 	if (rdev->mddev->bitmap_info.offset)
1606 		return 0; /* can't move bitmap */
1607 	rdev->sb_start = calc_dev_sboffset(rdev);
1608 	if (!num_sectors || num_sectors > rdev->sb_start)
1609 		num_sectors = rdev->sb_start;
1610 	/* Limit to 4TB as metadata cannot record more than that.
1611 	 * 4TB == 2^32 KB, or 2*2^32 sectors.
1612 	 */
1613 	if ((u64)num_sectors >= (2ULL << 32) && rdev->mddev->level >= 1)
1614 		num_sectors = (sector_t)(2ULL << 32) - 2;
1615 	do {
1616 		md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1617 		       rdev->sb_page);
1618 	} while (md_super_wait(rdev->mddev) < 0);
1619 	return num_sectors;
1620 }
1621 
1622 static int
super_90_allow_new_offset(struct md_rdev * rdev,unsigned long long new_offset)1623 super_90_allow_new_offset(struct md_rdev *rdev, unsigned long long new_offset)
1624 {
1625 	/* non-zero offset changes not possible with v0.90 */
1626 	return new_offset == 0;
1627 }
1628 
1629 /*
1630  * version 1 superblock
1631  */
1632 
calc_sb_1_csum(struct mdp_superblock_1 * sb)1633 static __le32 calc_sb_1_csum(struct mdp_superblock_1 *sb)
1634 {
1635 	__le32 disk_csum;
1636 	u32 csum;
1637 	unsigned long long newcsum;
1638 	int size = 256 + le32_to_cpu(sb->max_dev)*2;
1639 	__le32 *isuper = (__le32*)sb;
1640 
1641 	disk_csum = sb->sb_csum;
1642 	sb->sb_csum = 0;
1643 	newcsum = 0;
1644 	for (; size >= 4; size -= 4)
1645 		newcsum += le32_to_cpu(*isuper++);
1646 
1647 	if (size == 2)
1648 		newcsum += le16_to_cpu(*(__le16*) isuper);
1649 
1650 	csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1651 	sb->sb_csum = disk_csum;
1652 	return cpu_to_le32(csum);
1653 }
1654 
super_1_load(struct md_rdev * rdev,struct md_rdev * refdev,int minor_version)1655 static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1656 {
1657 	struct mdp_superblock_1 *sb;
1658 	int ret;
1659 	sector_t sb_start;
1660 	sector_t sectors;
1661 	int bmask;
1662 	bool spare_disk = true;
1663 
1664 	/*
1665 	 * Calculate the position of the superblock in 512byte sectors.
1666 	 * It is always aligned to a 4K boundary and
1667 	 * depeding on minor_version, it can be:
1668 	 * 0: At least 8K, but less than 12K, from end of device
1669 	 * 1: At start of device
1670 	 * 2: 4K from start of device.
1671 	 */
1672 	switch(minor_version) {
1673 	case 0:
1674 		sb_start = bdev_nr_sectors(rdev->bdev) - 8 * 2;
1675 		sb_start &= ~(sector_t)(4*2-1);
1676 		break;
1677 	case 1:
1678 		sb_start = 0;
1679 		break;
1680 	case 2:
1681 		sb_start = 8;
1682 		break;
1683 	default:
1684 		return -EINVAL;
1685 	}
1686 	rdev->sb_start = sb_start;
1687 
1688 	/* superblock is rarely larger than 1K, but it can be larger,
1689 	 * and it is safe to read 4k, so we do that
1690 	 */
1691 	ret = read_disk_sb(rdev, 4096);
1692 	if (ret) return ret;
1693 
1694 	sb = page_address(rdev->sb_page);
1695 
1696 	if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1697 	    sb->major_version != cpu_to_le32(1) ||
1698 	    le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1699 	    le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1700 	    (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1701 		return -EINVAL;
1702 
1703 	if (calc_sb_1_csum(sb) != sb->sb_csum) {
1704 		pr_warn("md: invalid superblock checksum on %pg\n",
1705 			rdev->bdev);
1706 		return -EINVAL;
1707 	}
1708 	if (le64_to_cpu(sb->data_size) < 10) {
1709 		pr_warn("md: data_size too small on %pg\n",
1710 			rdev->bdev);
1711 		return -EINVAL;
1712 	}
1713 	if (sb->pad0 ||
1714 	    sb->pad3[0] ||
1715 	    memcmp(sb->pad3, sb->pad3+1, sizeof(sb->pad3) - sizeof(sb->pad3[1])))
1716 		/* Some padding is non-zero, might be a new feature */
1717 		return -EINVAL;
1718 
1719 	rdev->preferred_minor = 0xffff;
1720 	rdev->data_offset = le64_to_cpu(sb->data_offset);
1721 	rdev->new_data_offset = rdev->data_offset;
1722 	if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE) &&
1723 	    (le32_to_cpu(sb->feature_map) & MD_FEATURE_NEW_OFFSET))
1724 		rdev->new_data_offset += (s32)le32_to_cpu(sb->new_offset);
1725 	atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1726 
1727 	rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1728 	bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1729 	if (rdev->sb_size & bmask)
1730 		rdev->sb_size = (rdev->sb_size | bmask) + 1;
1731 
1732 	if (minor_version
1733 	    && rdev->data_offset < sb_start + (rdev->sb_size/512))
1734 		return -EINVAL;
1735 	if (minor_version
1736 	    && rdev->new_data_offset < sb_start + (rdev->sb_size/512))
1737 		return -EINVAL;
1738 
1739 	rdev->desc_nr = le32_to_cpu(sb->dev_number);
1740 
1741 	if (!rdev->bb_page) {
1742 		rdev->bb_page = alloc_page(GFP_KERNEL);
1743 		if (!rdev->bb_page)
1744 			return -ENOMEM;
1745 	}
1746 	if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BAD_BLOCKS) &&
1747 	    rdev->badblocks.count == 0) {
1748 		/* need to load the bad block list.
1749 		 * Currently we limit it to one page.
1750 		 */
1751 		s32 offset;
1752 		sector_t bb_sector;
1753 		__le64 *bbp;
1754 		int i;
1755 		int sectors = le16_to_cpu(sb->bblog_size);
1756 		if (sectors > (PAGE_SIZE / 512))
1757 			return -EINVAL;
1758 		offset = le32_to_cpu(sb->bblog_offset);
1759 		if (offset == 0)
1760 			return -EINVAL;
1761 		bb_sector = (long long)offset;
1762 		if (!sync_page_io(rdev, bb_sector, sectors << 9,
1763 				  rdev->bb_page, REQ_OP_READ, true))
1764 			return -EIO;
1765 		bbp = (__le64 *)page_address(rdev->bb_page);
1766 		rdev->badblocks.shift = sb->bblog_shift;
1767 		for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1768 			u64 bb = le64_to_cpu(*bbp);
1769 			int count = bb & (0x3ff);
1770 			u64 sector = bb >> 10;
1771 			sector <<= sb->bblog_shift;
1772 			count <<= sb->bblog_shift;
1773 			if (bb + 1 == 0)
1774 				break;
1775 			if (!badblocks_set(&rdev->badblocks, sector, count, 1))
1776 				return -EINVAL;
1777 		}
1778 	} else if (sb->bblog_offset != 0)
1779 		rdev->badblocks.shift = 0;
1780 
1781 	if ((le32_to_cpu(sb->feature_map) &
1782 	    (MD_FEATURE_PPL | MD_FEATURE_MULTIPLE_PPLS))) {
1783 		rdev->ppl.offset = (__s16)le16_to_cpu(sb->ppl.offset);
1784 		rdev->ppl.size = le16_to_cpu(sb->ppl.size);
1785 		rdev->ppl.sector = rdev->sb_start + rdev->ppl.offset;
1786 	}
1787 
1788 	if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RAID0_LAYOUT) &&
1789 	    sb->level != 0)
1790 		return -EINVAL;
1791 
1792 	/* not spare disk */
1793 	if (rdev->desc_nr >= 0 && rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1794 	    (le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < MD_DISK_ROLE_MAX ||
1795 	     le16_to_cpu(sb->dev_roles[rdev->desc_nr]) == MD_DISK_ROLE_JOURNAL))
1796 		spare_disk = false;
1797 
1798 	if (!refdev) {
1799 		if (!spare_disk)
1800 			ret = 1;
1801 		else
1802 			ret = 0;
1803 	} else {
1804 		__u64 ev1, ev2;
1805 		struct mdp_superblock_1 *refsb = page_address(refdev->sb_page);
1806 
1807 		if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1808 		    sb->level != refsb->level ||
1809 		    sb->layout != refsb->layout ||
1810 		    sb->chunksize != refsb->chunksize) {
1811 			pr_warn("md: %pg has strangely different superblock to %pg\n",
1812 				rdev->bdev,
1813 				refdev->bdev);
1814 			return -EINVAL;
1815 		}
1816 		ev1 = le64_to_cpu(sb->events);
1817 		ev2 = le64_to_cpu(refsb->events);
1818 
1819 		if (!spare_disk && ev1 > ev2)
1820 			ret = 1;
1821 		else
1822 			ret = 0;
1823 	}
1824 	if (minor_version)
1825 		sectors = bdev_nr_sectors(rdev->bdev) - rdev->data_offset;
1826 	else
1827 		sectors = rdev->sb_start;
1828 	if (sectors < le64_to_cpu(sb->data_size))
1829 		return -EINVAL;
1830 	rdev->sectors = le64_to_cpu(sb->data_size);
1831 	return ret;
1832 }
1833 
super_1_validate(struct mddev * mddev,struct md_rdev * freshest,struct md_rdev * rdev)1834 static int super_1_validate(struct mddev *mddev, struct md_rdev *freshest, struct md_rdev *rdev)
1835 {
1836 	struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1837 	__u64 ev1 = le64_to_cpu(sb->events);
1838 	int role;
1839 
1840 	rdev->raid_disk = -1;
1841 	clear_bit(Faulty, &rdev->flags);
1842 	clear_bit(In_sync, &rdev->flags);
1843 	clear_bit(Bitmap_sync, &rdev->flags);
1844 	clear_bit(WriteMostly, &rdev->flags);
1845 
1846 	if (mddev->raid_disks == 0) {
1847 		mddev->major_version = 1;
1848 		mddev->patch_version = 0;
1849 		mddev->external = 0;
1850 		mddev->chunk_sectors = le32_to_cpu(sb->chunksize);
1851 		mddev->ctime = le64_to_cpu(sb->ctime);
1852 		mddev->utime = le64_to_cpu(sb->utime);
1853 		mddev->level = le32_to_cpu(sb->level);
1854 		mddev->clevel[0] = 0;
1855 		mddev->layout = le32_to_cpu(sb->layout);
1856 		mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1857 		mddev->dev_sectors = le64_to_cpu(sb->size);
1858 		mddev->events = ev1;
1859 		mddev->bitmap_info.offset = 0;
1860 		mddev->bitmap_info.space = 0;
1861 		/* Default location for bitmap is 1K after superblock
1862 		 * using 3K - total of 4K
1863 		 */
1864 		mddev->bitmap_info.default_offset = 1024 >> 9;
1865 		mddev->bitmap_info.default_space = (4096-1024) >> 9;
1866 		mddev->reshape_backwards = 0;
1867 
1868 		mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1869 		memcpy(mddev->uuid, sb->set_uuid, 16);
1870 
1871 		mddev->max_disks =  (4096-256)/2;
1872 
1873 		if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1874 		    mddev->bitmap_info.file == NULL) {
1875 			mddev->bitmap_info.offset =
1876 				(__s32)le32_to_cpu(sb->bitmap_offset);
1877 			/* Metadata doesn't record how much space is available.
1878 			 * For 1.0, we assume we can use up to the superblock
1879 			 * if before, else to 4K beyond superblock.
1880 			 * For others, assume no change is possible.
1881 			 */
1882 			if (mddev->minor_version > 0)
1883 				mddev->bitmap_info.space = 0;
1884 			else if (mddev->bitmap_info.offset > 0)
1885 				mddev->bitmap_info.space =
1886 					8 - mddev->bitmap_info.offset;
1887 			else
1888 				mddev->bitmap_info.space =
1889 					-mddev->bitmap_info.offset;
1890 		}
1891 
1892 		if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1893 			mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1894 			mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1895 			mddev->new_level = le32_to_cpu(sb->new_level);
1896 			mddev->new_layout = le32_to_cpu(sb->new_layout);
1897 			mddev->new_chunk_sectors = le32_to_cpu(sb->new_chunk);
1898 			if (mddev->delta_disks < 0 ||
1899 			    (mddev->delta_disks == 0 &&
1900 			     (le32_to_cpu(sb->feature_map)
1901 			      & MD_FEATURE_RESHAPE_BACKWARDS)))
1902 				mddev->reshape_backwards = 1;
1903 		} else {
1904 			mddev->reshape_position = MaxSector;
1905 			mddev->delta_disks = 0;
1906 			mddev->new_level = mddev->level;
1907 			mddev->new_layout = mddev->layout;
1908 			mddev->new_chunk_sectors = mddev->chunk_sectors;
1909 		}
1910 
1911 		if (mddev->level == 0 &&
1912 		    !(le32_to_cpu(sb->feature_map) & MD_FEATURE_RAID0_LAYOUT))
1913 			mddev->layout = -1;
1914 
1915 		if (le32_to_cpu(sb->feature_map) & MD_FEATURE_JOURNAL)
1916 			set_bit(MD_HAS_JOURNAL, &mddev->flags);
1917 
1918 		if (le32_to_cpu(sb->feature_map) &
1919 		    (MD_FEATURE_PPL | MD_FEATURE_MULTIPLE_PPLS)) {
1920 			if (le32_to_cpu(sb->feature_map) &
1921 			    (MD_FEATURE_BITMAP_OFFSET | MD_FEATURE_JOURNAL))
1922 				return -EINVAL;
1923 			if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_PPL) &&
1924 			    (le32_to_cpu(sb->feature_map) &
1925 					    MD_FEATURE_MULTIPLE_PPLS))
1926 				return -EINVAL;
1927 			set_bit(MD_HAS_PPL, &mddev->flags);
1928 		}
1929 	} else if (mddev->pers == NULL) {
1930 		/* Insist of good event counter while assembling, except for
1931 		 * spares (which don't need an event count).
1932 		 * Similar to mdadm, we allow event counter difference of 1
1933 		 * from the freshest device.
1934 		 */
1935 		if (rdev->desc_nr >= 0 &&
1936 		    rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1937 		    (le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < MD_DISK_ROLE_MAX ||
1938 		     le16_to_cpu(sb->dev_roles[rdev->desc_nr]) == MD_DISK_ROLE_JOURNAL))
1939 			if (ev1 + 1 < mddev->events)
1940 				return -EINVAL;
1941 	} else if (mddev->bitmap) {
1942 		/* If adding to array with a bitmap, then we can accept an
1943 		 * older device, but not too old.
1944 		 */
1945 		if (ev1 < md_bitmap_events_cleared(mddev))
1946 			return 0;
1947 		if (ev1 < mddev->events)
1948 			set_bit(Bitmap_sync, &rdev->flags);
1949 	} else {
1950 		if (ev1 < mddev->events)
1951 			/* just a hot-add of a new device, leave raid_disk at -1 */
1952 			return 0;
1953 	}
1954 
1955 	if (rdev->desc_nr < 0 ||
1956 	    rdev->desc_nr >= le32_to_cpu(sb->max_dev)) {
1957 		role = MD_DISK_ROLE_SPARE;
1958 		rdev->desc_nr = -1;
1959 	} else if (mddev->pers == NULL && freshest && ev1 < mddev->events) {
1960 		/*
1961 		 * If we are assembling, and our event counter is smaller than the
1962 		 * highest event counter, we cannot trust our superblock about the role.
1963 		 * It could happen that our rdev was marked as Faulty, and all other
1964 		 * superblocks were updated with +1 event counter.
1965 		 * Then, before the next superblock update, which typically happens when
1966 		 * remove_and_add_spares() removes the device from the array, there was
1967 		 * a crash or reboot.
1968 		 * If we allow current rdev without consulting the freshest superblock,
1969 		 * we could cause data corruption.
1970 		 * Note that in this case our event counter is smaller by 1 than the
1971 		 * highest, otherwise, this rdev would not be allowed into array;
1972 		 * both kernel and mdadm allow event counter difference of 1.
1973 		 */
1974 		struct mdp_superblock_1 *freshest_sb = page_address(freshest->sb_page);
1975 		u32 freshest_max_dev = le32_to_cpu(freshest_sb->max_dev);
1976 
1977 		if (rdev->desc_nr >= freshest_max_dev) {
1978 			/* this is unexpected, better not proceed */
1979 			pr_warn("md: %s: rdev[%pg]: desc_nr(%d) >= freshest(%pg)->sb->max_dev(%u)\n",
1980 				mdname(mddev), rdev->bdev, rdev->desc_nr,
1981 				freshest->bdev, freshest_max_dev);
1982 			return -EUCLEAN;
1983 		}
1984 
1985 		role = le16_to_cpu(freshest_sb->dev_roles[rdev->desc_nr]);
1986 		pr_debug("md: %s: rdev[%pg]: role=%d(0x%x) according to freshest %pg\n",
1987 			 mdname(mddev), rdev->bdev, role, role, freshest->bdev);
1988 	} else {
1989 		role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1990 	}
1991 	switch (role) {
1992 	case MD_DISK_ROLE_SPARE: /* spare */
1993 		break;
1994 	case MD_DISK_ROLE_FAULTY: /* faulty */
1995 		set_bit(Faulty, &rdev->flags);
1996 		break;
1997 	case MD_DISK_ROLE_JOURNAL: /* journal device */
1998 		if (!(le32_to_cpu(sb->feature_map) & MD_FEATURE_JOURNAL)) {
1999 			/* journal device without journal feature */
2000 			pr_warn("md: journal device provided without journal feature, ignoring the device\n");
2001 			return -EINVAL;
2002 		}
2003 		set_bit(Journal, &rdev->flags);
2004 		rdev->journal_tail = le64_to_cpu(sb->journal_tail);
2005 		rdev->raid_disk = 0;
2006 		break;
2007 	default:
2008 		rdev->saved_raid_disk = role;
2009 		if ((le32_to_cpu(sb->feature_map) &
2010 		     MD_FEATURE_RECOVERY_OFFSET)) {
2011 			rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
2012 			if (!(le32_to_cpu(sb->feature_map) &
2013 			      MD_FEATURE_RECOVERY_BITMAP))
2014 				rdev->saved_raid_disk = -1;
2015 		} else {
2016 			/*
2017 			 * If the array is FROZEN, then the device can't
2018 			 * be in_sync with rest of array.
2019 			 */
2020 			if (!test_bit(MD_RECOVERY_FROZEN,
2021 				      &mddev->recovery))
2022 				set_bit(In_sync, &rdev->flags);
2023 		}
2024 		rdev->raid_disk = role;
2025 		break;
2026 	}
2027 	if (sb->devflags & WriteMostly1)
2028 		set_bit(WriteMostly, &rdev->flags);
2029 	if (sb->devflags & FailFast1)
2030 		set_bit(FailFast, &rdev->flags);
2031 	if (le32_to_cpu(sb->feature_map) & MD_FEATURE_REPLACEMENT)
2032 		set_bit(Replacement, &rdev->flags);
2033 
2034 	return 0;
2035 }
2036 
super_1_sync(struct mddev * mddev,struct md_rdev * rdev)2037 static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
2038 {
2039 	struct mdp_superblock_1 *sb;
2040 	struct md_rdev *rdev2;
2041 	int max_dev, i;
2042 	/* make rdev->sb match mddev and rdev data. */
2043 
2044 	sb = page_address(rdev->sb_page);
2045 
2046 	sb->feature_map = 0;
2047 	sb->pad0 = 0;
2048 	sb->recovery_offset = cpu_to_le64(0);
2049 	memset(sb->pad3, 0, sizeof(sb->pad3));
2050 
2051 	sb->utime = cpu_to_le64((__u64)mddev->utime);
2052 	sb->events = cpu_to_le64(mddev->events);
2053 	if (mddev->in_sync)
2054 		sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
2055 	else if (test_bit(MD_JOURNAL_CLEAN, &mddev->flags))
2056 		sb->resync_offset = cpu_to_le64(MaxSector);
2057 	else
2058 		sb->resync_offset = cpu_to_le64(0);
2059 
2060 	sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
2061 
2062 	sb->raid_disks = cpu_to_le32(mddev->raid_disks);
2063 	sb->size = cpu_to_le64(mddev->dev_sectors);
2064 	sb->chunksize = cpu_to_le32(mddev->chunk_sectors);
2065 	sb->level = cpu_to_le32(mddev->level);
2066 	sb->layout = cpu_to_le32(mddev->layout);
2067 	if (test_bit(FailFast, &rdev->flags))
2068 		sb->devflags |= FailFast1;
2069 	else
2070 		sb->devflags &= ~FailFast1;
2071 
2072 	if (test_bit(WriteMostly, &rdev->flags))
2073 		sb->devflags |= WriteMostly1;
2074 	else
2075 		sb->devflags &= ~WriteMostly1;
2076 	sb->data_offset = cpu_to_le64(rdev->data_offset);
2077 	sb->data_size = cpu_to_le64(rdev->sectors);
2078 
2079 	if (mddev->bitmap && mddev->bitmap_info.file == NULL) {
2080 		sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_info.offset);
2081 		sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
2082 	}
2083 
2084 	if (rdev->raid_disk >= 0 && !test_bit(Journal, &rdev->flags) &&
2085 	    !test_bit(In_sync, &rdev->flags)) {
2086 		sb->feature_map |=
2087 			cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
2088 		sb->recovery_offset =
2089 			cpu_to_le64(rdev->recovery_offset);
2090 		if (rdev->saved_raid_disk >= 0 && mddev->bitmap)
2091 			sb->feature_map |=
2092 				cpu_to_le32(MD_FEATURE_RECOVERY_BITMAP);
2093 	}
2094 	/* Note: recovery_offset and journal_tail share space  */
2095 	if (test_bit(Journal, &rdev->flags))
2096 		sb->journal_tail = cpu_to_le64(rdev->journal_tail);
2097 	if (test_bit(Replacement, &rdev->flags))
2098 		sb->feature_map |=
2099 			cpu_to_le32(MD_FEATURE_REPLACEMENT);
2100 
2101 	if (mddev->reshape_position != MaxSector) {
2102 		sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
2103 		sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2104 		sb->new_layout = cpu_to_le32(mddev->new_layout);
2105 		sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2106 		sb->new_level = cpu_to_le32(mddev->new_level);
2107 		sb->new_chunk = cpu_to_le32(mddev->new_chunk_sectors);
2108 		if (mddev->delta_disks == 0 &&
2109 		    mddev->reshape_backwards)
2110 			sb->feature_map
2111 				|= cpu_to_le32(MD_FEATURE_RESHAPE_BACKWARDS);
2112 		if (rdev->new_data_offset != rdev->data_offset) {
2113 			sb->feature_map
2114 				|= cpu_to_le32(MD_FEATURE_NEW_OFFSET);
2115 			sb->new_offset = cpu_to_le32((__u32)(rdev->new_data_offset
2116 							     - rdev->data_offset));
2117 		}
2118 	}
2119 
2120 	if (mddev_is_clustered(mddev))
2121 		sb->feature_map |= cpu_to_le32(MD_FEATURE_CLUSTERED);
2122 
2123 	if (rdev->badblocks.count == 0)
2124 		/* Nothing to do for bad blocks*/ ;
2125 	else if (sb->bblog_offset == 0)
2126 		/* Cannot record bad blocks on this device */
2127 		md_error(mddev, rdev);
2128 	else {
2129 		struct badblocks *bb = &rdev->badblocks;
2130 		__le64 *bbp = (__le64 *)page_address(rdev->bb_page);
2131 		u64 *p = bb->page;
2132 		sb->feature_map |= cpu_to_le32(MD_FEATURE_BAD_BLOCKS);
2133 		if (bb->changed) {
2134 			unsigned seq;
2135 
2136 retry:
2137 			seq = read_seqbegin(&bb->lock);
2138 
2139 			memset(bbp, 0xff, PAGE_SIZE);
2140 
2141 			for (i = 0 ; i < bb->count ; i++) {
2142 				u64 internal_bb = p[i];
2143 				u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
2144 						| BB_LEN(internal_bb));
2145 				bbp[i] = cpu_to_le64(store_bb);
2146 			}
2147 			bb->changed = 0;
2148 			if (read_seqretry(&bb->lock, seq))
2149 				goto retry;
2150 
2151 			bb->sector = (rdev->sb_start +
2152 				      (int)le32_to_cpu(sb->bblog_offset));
2153 			bb->size = le16_to_cpu(sb->bblog_size);
2154 		}
2155 	}
2156 
2157 	max_dev = 0;
2158 	rdev_for_each(rdev2, mddev)
2159 		if (rdev2->desc_nr+1 > max_dev)
2160 			max_dev = rdev2->desc_nr+1;
2161 
2162 	if (max_dev > le32_to_cpu(sb->max_dev)) {
2163 		int bmask;
2164 		sb->max_dev = cpu_to_le32(max_dev);
2165 		rdev->sb_size = max_dev * 2 + 256;
2166 		bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
2167 		if (rdev->sb_size & bmask)
2168 			rdev->sb_size = (rdev->sb_size | bmask) + 1;
2169 	} else
2170 		max_dev = le32_to_cpu(sb->max_dev);
2171 
2172 	for (i=0; i<max_dev;i++)
2173 		sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_SPARE);
2174 
2175 	if (test_bit(MD_HAS_JOURNAL, &mddev->flags))
2176 		sb->feature_map |= cpu_to_le32(MD_FEATURE_JOURNAL);
2177 
2178 	if (test_bit(MD_HAS_PPL, &mddev->flags)) {
2179 		if (test_bit(MD_HAS_MULTIPLE_PPLS, &mddev->flags))
2180 			sb->feature_map |=
2181 			    cpu_to_le32(MD_FEATURE_MULTIPLE_PPLS);
2182 		else
2183 			sb->feature_map |= cpu_to_le32(MD_FEATURE_PPL);
2184 		sb->ppl.offset = cpu_to_le16(rdev->ppl.offset);
2185 		sb->ppl.size = cpu_to_le16(rdev->ppl.size);
2186 	}
2187 
2188 	rdev_for_each(rdev2, mddev) {
2189 		i = rdev2->desc_nr;
2190 		if (test_bit(Faulty, &rdev2->flags))
2191 			sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_FAULTY);
2192 		else if (test_bit(In_sync, &rdev2->flags))
2193 			sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
2194 		else if (test_bit(Journal, &rdev2->flags))
2195 			sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_JOURNAL);
2196 		else if (rdev2->raid_disk >= 0)
2197 			sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
2198 		else
2199 			sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_SPARE);
2200 	}
2201 
2202 	sb->sb_csum = calc_sb_1_csum(sb);
2203 }
2204 
super_1_choose_bm_space(sector_t dev_size)2205 static sector_t super_1_choose_bm_space(sector_t dev_size)
2206 {
2207 	sector_t bm_space;
2208 
2209 	/* if the device is bigger than 8Gig, save 64k for bitmap
2210 	 * usage, if bigger than 200Gig, save 128k
2211 	 */
2212 	if (dev_size < 64*2)
2213 		bm_space = 0;
2214 	else if (dev_size - 64*2 >= 200*1024*1024*2)
2215 		bm_space = 128*2;
2216 	else if (dev_size - 4*2 > 8*1024*1024*2)
2217 		bm_space = 64*2;
2218 	else
2219 		bm_space = 4*2;
2220 	return bm_space;
2221 }
2222 
2223 static unsigned long long
super_1_rdev_size_change(struct md_rdev * rdev,sector_t num_sectors)2224 super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
2225 {
2226 	struct mdp_superblock_1 *sb;
2227 	sector_t max_sectors;
2228 	if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
2229 		return 0; /* component must fit device */
2230 	if (rdev->data_offset != rdev->new_data_offset)
2231 		return 0; /* too confusing */
2232 	if (rdev->sb_start < rdev->data_offset) {
2233 		/* minor versions 1 and 2; superblock before data */
2234 		max_sectors = bdev_nr_sectors(rdev->bdev) - rdev->data_offset;
2235 		if (!num_sectors || num_sectors > max_sectors)
2236 			num_sectors = max_sectors;
2237 	} else if (rdev->mddev->bitmap_info.offset) {
2238 		/* minor version 0 with bitmap we can't move */
2239 		return 0;
2240 	} else {
2241 		/* minor version 0; superblock after data */
2242 		sector_t sb_start, bm_space;
2243 		sector_t dev_size = bdev_nr_sectors(rdev->bdev);
2244 
2245 		/* 8K is for superblock */
2246 		sb_start = dev_size - 8*2;
2247 		sb_start &= ~(sector_t)(4*2 - 1);
2248 
2249 		bm_space = super_1_choose_bm_space(dev_size);
2250 
2251 		/* Space that can be used to store date needs to decrease
2252 		 * superblock bitmap space and bad block space(4K)
2253 		 */
2254 		max_sectors = sb_start - bm_space - 4*2;
2255 
2256 		if (!num_sectors || num_sectors > max_sectors)
2257 			num_sectors = max_sectors;
2258 		rdev->sb_start = sb_start;
2259 	}
2260 	sb = page_address(rdev->sb_page);
2261 	sb->data_size = cpu_to_le64(num_sectors);
2262 	sb->super_offset = cpu_to_le64(rdev->sb_start);
2263 	sb->sb_csum = calc_sb_1_csum(sb);
2264 	do {
2265 		md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
2266 			       rdev->sb_page);
2267 	} while (md_super_wait(rdev->mddev) < 0);
2268 	return num_sectors;
2269 
2270 }
2271 
2272 static int
super_1_allow_new_offset(struct md_rdev * rdev,unsigned long long new_offset)2273 super_1_allow_new_offset(struct md_rdev *rdev,
2274 			 unsigned long long new_offset)
2275 {
2276 	/* All necessary checks on new >= old have been done */
2277 	if (new_offset >= rdev->data_offset)
2278 		return 1;
2279 
2280 	/* with 1.0 metadata, there is no metadata to tread on
2281 	 * so we can always move back */
2282 	if (rdev->mddev->minor_version == 0)
2283 		return 1;
2284 
2285 	/* otherwise we must be sure not to step on
2286 	 * any metadata, so stay:
2287 	 * 36K beyond start of superblock
2288 	 * beyond end of badblocks
2289 	 * beyond write-intent bitmap
2290 	 */
2291 	if (rdev->sb_start + (32+4)*2 > new_offset)
2292 		return 0;
2293 
2294 	if (!rdev->mddev->bitmap_info.file) {
2295 		struct mddev *mddev = rdev->mddev;
2296 		struct md_bitmap_stats stats;
2297 		int err;
2298 
2299 		err = mddev->bitmap_ops->get_stats(mddev->bitmap, &stats);
2300 		if (!err && rdev->sb_start + mddev->bitmap_info.offset +
2301 		    stats.file_pages * (PAGE_SIZE >> 9) > new_offset)
2302 			return 0;
2303 	}
2304 
2305 	if (rdev->badblocks.sector + rdev->badblocks.size > new_offset)
2306 		return 0;
2307 
2308 	return 1;
2309 }
2310 
2311 static struct super_type super_types[] = {
2312 	[0] = {
2313 		.name	= "0.90.0",
2314 		.owner	= THIS_MODULE,
2315 		.load_super	    = super_90_load,
2316 		.validate_super	    = super_90_validate,
2317 		.sync_super	    = super_90_sync,
2318 		.rdev_size_change   = super_90_rdev_size_change,
2319 		.allow_new_offset   = super_90_allow_new_offset,
2320 	},
2321 	[1] = {
2322 		.name	= "md-1",
2323 		.owner	= THIS_MODULE,
2324 		.load_super	    = super_1_load,
2325 		.validate_super	    = super_1_validate,
2326 		.sync_super	    = super_1_sync,
2327 		.rdev_size_change   = super_1_rdev_size_change,
2328 		.allow_new_offset   = super_1_allow_new_offset,
2329 	},
2330 };
2331 
sync_super(struct mddev * mddev,struct md_rdev * rdev)2332 static void sync_super(struct mddev *mddev, struct md_rdev *rdev)
2333 {
2334 	if (mddev->sync_super) {
2335 		mddev->sync_super(mddev, rdev);
2336 		return;
2337 	}
2338 
2339 	BUG_ON(mddev->major_version >= ARRAY_SIZE(super_types));
2340 
2341 	super_types[mddev->major_version].sync_super(mddev, rdev);
2342 }
2343 
match_mddev_units(struct mddev * mddev1,struct mddev * mddev2)2344 static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
2345 {
2346 	struct md_rdev *rdev, *rdev2;
2347 
2348 	rcu_read_lock();
2349 	rdev_for_each_rcu(rdev, mddev1) {
2350 		if (test_bit(Faulty, &rdev->flags) ||
2351 		    test_bit(Journal, &rdev->flags) ||
2352 		    rdev->raid_disk == -1)
2353 			continue;
2354 		rdev_for_each_rcu(rdev2, mddev2) {
2355 			if (test_bit(Faulty, &rdev2->flags) ||
2356 			    test_bit(Journal, &rdev2->flags) ||
2357 			    rdev2->raid_disk == -1)
2358 				continue;
2359 			if (rdev->bdev->bd_disk == rdev2->bdev->bd_disk) {
2360 				rcu_read_unlock();
2361 				return 1;
2362 			}
2363 		}
2364 	}
2365 	rcu_read_unlock();
2366 	return 0;
2367 }
2368 
2369 static LIST_HEAD(pending_raid_disks);
2370 
2371 /*
2372  * Try to register data integrity profile for an mddev
2373  *
2374  * This is called when an array is started and after a disk has been kicked
2375  * from the array. It only succeeds if all working and active component devices
2376  * are integrity capable with matching profiles.
2377  */
md_integrity_register(struct mddev * mddev)2378 int md_integrity_register(struct mddev *mddev)
2379 {
2380 	if (list_empty(&mddev->disks))
2381 		return 0; /* nothing to do */
2382 	if (mddev_is_dm(mddev) || !blk_get_integrity(mddev->gendisk))
2383 		return 0; /* shouldn't register */
2384 
2385 	pr_debug("md: data integrity enabled on %s\n", mdname(mddev));
2386 	return 0;
2387 }
2388 EXPORT_SYMBOL(md_integrity_register);
2389 
rdev_read_only(struct md_rdev * rdev)2390 static bool rdev_read_only(struct md_rdev *rdev)
2391 {
2392 	return bdev_read_only(rdev->bdev) ||
2393 		(rdev->meta_bdev && bdev_read_only(rdev->meta_bdev));
2394 }
2395 
bind_rdev_to_array(struct md_rdev * rdev,struct mddev * mddev)2396 static int bind_rdev_to_array(struct md_rdev *rdev, struct mddev *mddev)
2397 {
2398 	char b[BDEVNAME_SIZE];
2399 	int err;
2400 
2401 	/* prevent duplicates */
2402 	if (find_rdev(mddev, rdev->bdev->bd_dev))
2403 		return -EEXIST;
2404 
2405 	if (rdev_read_only(rdev) && mddev->pers)
2406 		return -EROFS;
2407 
2408 	/* make sure rdev->sectors exceeds mddev->dev_sectors */
2409 	if (!test_bit(Journal, &rdev->flags) &&
2410 	    rdev->sectors &&
2411 	    (mddev->dev_sectors == 0 || rdev->sectors < mddev->dev_sectors)) {
2412 		if (mddev->pers) {
2413 			/* Cannot change size, so fail
2414 			 * If mddev->level <= 0, then we don't care
2415 			 * about aligning sizes (e.g. linear)
2416 			 */
2417 			if (mddev->level > 0)
2418 				return -ENOSPC;
2419 		} else
2420 			mddev->dev_sectors = rdev->sectors;
2421 	}
2422 
2423 	/* Verify rdev->desc_nr is unique.
2424 	 * If it is -1, assign a free number, else
2425 	 * check number is not in use
2426 	 */
2427 	rcu_read_lock();
2428 	if (rdev->desc_nr < 0) {
2429 		int choice = 0;
2430 		if (mddev->pers)
2431 			choice = mddev->raid_disks;
2432 		while (md_find_rdev_nr_rcu(mddev, choice))
2433 			choice++;
2434 		rdev->desc_nr = choice;
2435 	} else {
2436 		if (md_find_rdev_nr_rcu(mddev, rdev->desc_nr)) {
2437 			rcu_read_unlock();
2438 			return -EBUSY;
2439 		}
2440 	}
2441 	rcu_read_unlock();
2442 	if (!test_bit(Journal, &rdev->flags) &&
2443 	    mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
2444 		pr_warn("md: %s: array is limited to %d devices\n",
2445 			mdname(mddev), mddev->max_disks);
2446 		return -EBUSY;
2447 	}
2448 	snprintf(b, sizeof(b), "%pg", rdev->bdev);
2449 	strreplace(b, '/', '!');
2450 
2451 	rdev->mddev = mddev;
2452 	pr_debug("md: bind<%s>\n", b);
2453 
2454 	if (mddev->raid_disks)
2455 		mddev_create_serial_pool(mddev, rdev);
2456 
2457 	if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
2458 		goto fail;
2459 
2460 	/* failure here is OK */
2461 	err = sysfs_create_link(&rdev->kobj, bdev_kobj(rdev->bdev), "block");
2462 	rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
2463 	rdev->sysfs_unack_badblocks =
2464 		sysfs_get_dirent_safe(rdev->kobj.sd, "unacknowledged_bad_blocks");
2465 	rdev->sysfs_badblocks =
2466 		sysfs_get_dirent_safe(rdev->kobj.sd, "bad_blocks");
2467 
2468 	list_add_rcu(&rdev->same_set, &mddev->disks);
2469 	bd_link_disk_holder(rdev->bdev, mddev->gendisk);
2470 
2471 	/* May as well allow recovery to be retried once */
2472 	mddev->recovery_disabled++;
2473 
2474 	return 0;
2475 
2476  fail:
2477 	pr_warn("md: failed to register dev-%s for %s\n",
2478 		b, mdname(mddev));
2479 	mddev_destroy_serial_pool(mddev, rdev);
2480 	return err;
2481 }
2482 
2483 void md_autodetect_dev(dev_t dev);
2484 
2485 /* just for claiming the bdev */
2486 static struct md_rdev claim_rdev;
2487 
export_rdev(struct md_rdev * rdev,struct mddev * mddev)2488 static void export_rdev(struct md_rdev *rdev, struct mddev *mddev)
2489 {
2490 	pr_debug("md: export_rdev(%pg)\n", rdev->bdev);
2491 	md_rdev_clear(rdev);
2492 #ifndef MODULE
2493 	if (test_bit(AutoDetected, &rdev->flags))
2494 		md_autodetect_dev(rdev->bdev->bd_dev);
2495 #endif
2496 	fput(rdev->bdev_file);
2497 	rdev->bdev = NULL;
2498 	kobject_put(&rdev->kobj);
2499 }
2500 
md_kick_rdev_from_array(struct md_rdev * rdev)2501 static void md_kick_rdev_from_array(struct md_rdev *rdev)
2502 {
2503 	struct mddev *mddev = rdev->mddev;
2504 
2505 	bd_unlink_disk_holder(rdev->bdev, rdev->mddev->gendisk);
2506 	list_del_rcu(&rdev->same_set);
2507 	pr_debug("md: unbind<%pg>\n", rdev->bdev);
2508 	mddev_destroy_serial_pool(rdev->mddev, rdev);
2509 	WRITE_ONCE(rdev->mddev, NULL);
2510 	sysfs_remove_link(&rdev->kobj, "block");
2511 	sysfs_put(rdev->sysfs_state);
2512 	sysfs_put(rdev->sysfs_unack_badblocks);
2513 	sysfs_put(rdev->sysfs_badblocks);
2514 	rdev->sysfs_state = NULL;
2515 	rdev->sysfs_unack_badblocks = NULL;
2516 	rdev->sysfs_badblocks = NULL;
2517 	rdev->badblocks.count = 0;
2518 
2519 	synchronize_rcu();
2520 
2521 	/*
2522 	 * kobject_del() will wait for all in progress writers to be done, where
2523 	 * reconfig_mutex is held, hence it can't be called under
2524 	 * reconfig_mutex and it's delayed to mddev_unlock().
2525 	 */
2526 	list_add(&rdev->same_set, &mddev->deleting);
2527 }
2528 
export_array(struct mddev * mddev)2529 static void export_array(struct mddev *mddev)
2530 {
2531 	struct md_rdev *rdev;
2532 
2533 	while (!list_empty(&mddev->disks)) {
2534 		rdev = list_first_entry(&mddev->disks, struct md_rdev,
2535 					same_set);
2536 		md_kick_rdev_from_array(rdev);
2537 	}
2538 	mddev->raid_disks = 0;
2539 	mddev->major_version = 0;
2540 }
2541 
set_in_sync(struct mddev * mddev)2542 static bool set_in_sync(struct mddev *mddev)
2543 {
2544 	lockdep_assert_held(&mddev->lock);
2545 	if (!mddev->in_sync) {
2546 		mddev->sync_checkers++;
2547 		spin_unlock(&mddev->lock);
2548 		percpu_ref_switch_to_atomic_sync(&mddev->writes_pending);
2549 		spin_lock(&mddev->lock);
2550 		if (!mddev->in_sync &&
2551 		    percpu_ref_is_zero(&mddev->writes_pending)) {
2552 			mddev->in_sync = 1;
2553 			/*
2554 			 * Ensure ->in_sync is visible before we clear
2555 			 * ->sync_checkers.
2556 			 */
2557 			smp_mb();
2558 			set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
2559 			sysfs_notify_dirent_safe(mddev->sysfs_state);
2560 		}
2561 		if (--mddev->sync_checkers == 0)
2562 			percpu_ref_switch_to_percpu(&mddev->writes_pending);
2563 	}
2564 	if (mddev->safemode == 1)
2565 		mddev->safemode = 0;
2566 	return mddev->in_sync;
2567 }
2568 
sync_sbs(struct mddev * mddev,int nospares)2569 static void sync_sbs(struct mddev *mddev, int nospares)
2570 {
2571 	/* Update each superblock (in-memory image), but
2572 	 * if we are allowed to, skip spares which already
2573 	 * have the right event counter, or have one earlier
2574 	 * (which would mean they aren't being marked as dirty
2575 	 * with the rest of the array)
2576 	 */
2577 	struct md_rdev *rdev;
2578 	rdev_for_each(rdev, mddev) {
2579 		if (rdev->sb_events == mddev->events ||
2580 		    (nospares &&
2581 		     rdev->raid_disk < 0 &&
2582 		     rdev->sb_events+1 == mddev->events)) {
2583 			/* Don't update this superblock */
2584 			rdev->sb_loaded = 2;
2585 		} else {
2586 			sync_super(mddev, rdev);
2587 			rdev->sb_loaded = 1;
2588 		}
2589 	}
2590 }
2591 
does_sb_need_changing(struct mddev * mddev)2592 static bool does_sb_need_changing(struct mddev *mddev)
2593 {
2594 	struct md_rdev *rdev = NULL, *iter;
2595 	struct mdp_superblock_1 *sb;
2596 	int role;
2597 
2598 	/* Find a good rdev */
2599 	rdev_for_each(iter, mddev)
2600 		if ((iter->raid_disk >= 0) && !test_bit(Faulty, &iter->flags)) {
2601 			rdev = iter;
2602 			break;
2603 		}
2604 
2605 	/* No good device found. */
2606 	if (!rdev)
2607 		return false;
2608 
2609 	sb = page_address(rdev->sb_page);
2610 	/* Check if a device has become faulty or a spare become active */
2611 	rdev_for_each(rdev, mddev) {
2612 		role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
2613 		/* Device activated? */
2614 		if (role == MD_DISK_ROLE_SPARE && rdev->raid_disk >= 0 &&
2615 		    !test_bit(Faulty, &rdev->flags))
2616 			return true;
2617 		/* Device turned faulty? */
2618 		if (test_bit(Faulty, &rdev->flags) && (role < MD_DISK_ROLE_MAX))
2619 			return true;
2620 	}
2621 
2622 	/* Check if any mddev parameters have changed */
2623 	if ((mddev->dev_sectors != le64_to_cpu(sb->size)) ||
2624 	    (mddev->reshape_position != le64_to_cpu(sb->reshape_position)) ||
2625 	    (mddev->layout != le32_to_cpu(sb->layout)) ||
2626 	    (mddev->raid_disks != le32_to_cpu(sb->raid_disks)) ||
2627 	    (mddev->chunk_sectors != le32_to_cpu(sb->chunksize)))
2628 		return true;
2629 
2630 	return false;
2631 }
2632 
md_update_sb(struct mddev * mddev,int force_change)2633 void md_update_sb(struct mddev *mddev, int force_change)
2634 {
2635 	struct md_rdev *rdev;
2636 	int sync_req;
2637 	int nospares = 0;
2638 	int any_badblocks_changed = 0;
2639 	int ret = -1;
2640 
2641 	if (!md_is_rdwr(mddev)) {
2642 		if (force_change)
2643 			set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2644 		return;
2645 	}
2646 
2647 repeat:
2648 	if (mddev_is_clustered(mddev)) {
2649 		if (test_and_clear_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags))
2650 			force_change = 1;
2651 		if (test_and_clear_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags))
2652 			nospares = 1;
2653 		ret = mddev->cluster_ops->metadata_update_start(mddev);
2654 		/* Has someone else has updated the sb */
2655 		if (!does_sb_need_changing(mddev)) {
2656 			if (ret == 0)
2657 				mddev->cluster_ops->metadata_update_cancel(mddev);
2658 			bit_clear_unless(&mddev->sb_flags, BIT(MD_SB_CHANGE_PENDING),
2659 							 BIT(MD_SB_CHANGE_DEVS) |
2660 							 BIT(MD_SB_CHANGE_CLEAN));
2661 			return;
2662 		}
2663 	}
2664 
2665 	/*
2666 	 * First make sure individual recovery_offsets are correct
2667 	 * curr_resync_completed can only be used during recovery.
2668 	 * During reshape/resync it might use array-addresses rather
2669 	 * that device addresses.
2670 	 */
2671 	rdev_for_each(rdev, mddev) {
2672 		if (rdev->raid_disk >= 0 &&
2673 		    mddev->delta_disks >= 0 &&
2674 		    test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
2675 		    test_bit(MD_RECOVERY_RECOVER, &mddev->recovery) &&
2676 		    !test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
2677 		    !test_bit(Journal, &rdev->flags) &&
2678 		    !test_bit(In_sync, &rdev->flags) &&
2679 		    mddev->curr_resync_completed > rdev->recovery_offset)
2680 				rdev->recovery_offset = mddev->curr_resync_completed;
2681 
2682 	}
2683 	if (!mddev->persistent) {
2684 		clear_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
2685 		clear_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2686 		if (!mddev->external) {
2687 			clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
2688 			rdev_for_each(rdev, mddev) {
2689 				if (rdev->badblocks.changed) {
2690 					rdev->badblocks.changed = 0;
2691 					ack_all_badblocks(&rdev->badblocks);
2692 					md_error(mddev, rdev);
2693 				}
2694 				clear_bit(Blocked, &rdev->flags);
2695 				clear_bit(BlockedBadBlocks, &rdev->flags);
2696 				wake_up(&rdev->blocked_wait);
2697 			}
2698 		}
2699 		wake_up(&mddev->sb_wait);
2700 		return;
2701 	}
2702 
2703 	spin_lock(&mddev->lock);
2704 
2705 	mddev->utime = ktime_get_real_seconds();
2706 
2707 	if (test_and_clear_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags))
2708 		force_change = 1;
2709 	if (test_and_clear_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags))
2710 		/* just a clean<-> dirty transition, possibly leave spares alone,
2711 		 * though if events isn't the right even/odd, we will have to do
2712 		 * spares after all
2713 		 */
2714 		nospares = 1;
2715 	if (force_change)
2716 		nospares = 0;
2717 	if (mddev->degraded)
2718 		/* If the array is degraded, then skipping spares is both
2719 		 * dangerous and fairly pointless.
2720 		 * Dangerous because a device that was removed from the array
2721 		 * might have a event_count that still looks up-to-date,
2722 		 * so it can be re-added without a resync.
2723 		 * Pointless because if there are any spares to skip,
2724 		 * then a recovery will happen and soon that array won't
2725 		 * be degraded any more and the spare can go back to sleep then.
2726 		 */
2727 		nospares = 0;
2728 
2729 	sync_req = mddev->in_sync;
2730 
2731 	/* If this is just a dirty<->clean transition, and the array is clean
2732 	 * and 'events' is odd, we can roll back to the previous clean state */
2733 	if (nospares
2734 	    && (mddev->in_sync && mddev->recovery_cp == MaxSector)
2735 	    && mddev->can_decrease_events
2736 	    && mddev->events != 1) {
2737 		mddev->events--;
2738 		mddev->can_decrease_events = 0;
2739 	} else {
2740 		/* otherwise we have to go forward and ... */
2741 		mddev->events ++;
2742 		mddev->can_decrease_events = nospares;
2743 	}
2744 
2745 	/*
2746 	 * This 64-bit counter should never wrap.
2747 	 * Either we are in around ~1 trillion A.C., assuming
2748 	 * 1 reboot per second, or we have a bug...
2749 	 */
2750 	WARN_ON(mddev->events == 0);
2751 
2752 	rdev_for_each(rdev, mddev) {
2753 		if (rdev->badblocks.changed)
2754 			any_badblocks_changed++;
2755 		if (test_bit(Faulty, &rdev->flags))
2756 			set_bit(FaultRecorded, &rdev->flags);
2757 	}
2758 
2759 	sync_sbs(mddev, nospares);
2760 	spin_unlock(&mddev->lock);
2761 
2762 	pr_debug("md: updating %s RAID superblock on device (in sync %d)\n",
2763 		 mdname(mddev), mddev->in_sync);
2764 
2765 	mddev_add_trace_msg(mddev, "md md_update_sb");
2766 rewrite:
2767 	mddev->bitmap_ops->update_sb(mddev->bitmap);
2768 	rdev_for_each(rdev, mddev) {
2769 		if (rdev->sb_loaded != 1)
2770 			continue; /* no noise on spare devices */
2771 
2772 		if (!test_bit(Faulty, &rdev->flags)) {
2773 			md_super_write(mddev,rdev,
2774 				       rdev->sb_start, rdev->sb_size,
2775 				       rdev->sb_page);
2776 			pr_debug("md: (write) %pg's sb offset: %llu\n",
2777 				 rdev->bdev,
2778 				 (unsigned long long)rdev->sb_start);
2779 			rdev->sb_events = mddev->events;
2780 			if (rdev->badblocks.size) {
2781 				md_super_write(mddev, rdev,
2782 					       rdev->badblocks.sector,
2783 					       rdev->badblocks.size << 9,
2784 					       rdev->bb_page);
2785 				rdev->badblocks.size = 0;
2786 			}
2787 
2788 		} else
2789 			pr_debug("md: %pg (skipping faulty)\n",
2790 				 rdev->bdev);
2791 	}
2792 	if (md_super_wait(mddev) < 0)
2793 		goto rewrite;
2794 	/* if there was a failure, MD_SB_CHANGE_DEVS was set, and we re-write super */
2795 
2796 	if (mddev_is_clustered(mddev) && ret == 0)
2797 		mddev->cluster_ops->metadata_update_finish(mddev);
2798 
2799 	if (mddev->in_sync != sync_req ||
2800 	    !bit_clear_unless(&mddev->sb_flags, BIT(MD_SB_CHANGE_PENDING),
2801 			       BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_CLEAN)))
2802 		/* have to write it out again */
2803 		goto repeat;
2804 	wake_up(&mddev->sb_wait);
2805 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2806 		sysfs_notify_dirent_safe(mddev->sysfs_completed);
2807 
2808 	rdev_for_each(rdev, mddev) {
2809 		if (test_and_clear_bit(FaultRecorded, &rdev->flags))
2810 			clear_bit(Blocked, &rdev->flags);
2811 
2812 		if (any_badblocks_changed)
2813 			ack_all_badblocks(&rdev->badblocks);
2814 		clear_bit(BlockedBadBlocks, &rdev->flags);
2815 		wake_up(&rdev->blocked_wait);
2816 	}
2817 }
2818 EXPORT_SYMBOL(md_update_sb);
2819 
add_bound_rdev(struct md_rdev * rdev)2820 static int add_bound_rdev(struct md_rdev *rdev)
2821 {
2822 	struct mddev *mddev = rdev->mddev;
2823 	int err = 0;
2824 	bool add_journal = test_bit(Journal, &rdev->flags);
2825 
2826 	if (!mddev->pers->hot_remove_disk || add_journal) {
2827 		/* If there is hot_add_disk but no hot_remove_disk
2828 		 * then added disks for geometry changes,
2829 		 * and should be added immediately.
2830 		 */
2831 		super_types[mddev->major_version].
2832 			validate_super(mddev, NULL/*freshest*/, rdev);
2833 		err = mddev->pers->hot_add_disk(mddev, rdev);
2834 		if (err) {
2835 			md_kick_rdev_from_array(rdev);
2836 			return err;
2837 		}
2838 	}
2839 	sysfs_notify_dirent_safe(rdev->sysfs_state);
2840 
2841 	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2842 	if (mddev->degraded)
2843 		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
2844 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2845 	md_new_event();
2846 	return 0;
2847 }
2848 
2849 /* words written to sysfs files may, or may not, be \n terminated.
2850  * We want to accept with case. For this we use cmd_match.
2851  */
cmd_match(const char * cmd,const char * str)2852 static int cmd_match(const char *cmd, const char *str)
2853 {
2854 	/* See if cmd, written into a sysfs file, matches
2855 	 * str.  They must either be the same, or cmd can
2856 	 * have a trailing newline
2857 	 */
2858 	while (*cmd && *str && *cmd == *str) {
2859 		cmd++;
2860 		str++;
2861 	}
2862 	if (*cmd == '\n')
2863 		cmd++;
2864 	if (*str || *cmd)
2865 		return 0;
2866 	return 1;
2867 }
2868 
2869 struct rdev_sysfs_entry {
2870 	struct attribute attr;
2871 	ssize_t (*show)(struct md_rdev *, char *);
2872 	ssize_t (*store)(struct md_rdev *, const char *, size_t);
2873 };
2874 
2875 static ssize_t
state_show(struct md_rdev * rdev,char * page)2876 state_show(struct md_rdev *rdev, char *page)
2877 {
2878 	char *sep = ",";
2879 	size_t len = 0;
2880 	unsigned long flags = READ_ONCE(rdev->flags);
2881 
2882 	if (test_bit(Faulty, &flags) ||
2883 	    (!test_bit(ExternalBbl, &flags) &&
2884 	    rdev->badblocks.unacked_exist))
2885 		len += sprintf(page+len, "faulty%s", sep);
2886 	if (test_bit(In_sync, &flags))
2887 		len += sprintf(page+len, "in_sync%s", sep);
2888 	if (test_bit(Journal, &flags))
2889 		len += sprintf(page+len, "journal%s", sep);
2890 	if (test_bit(WriteMostly, &flags))
2891 		len += sprintf(page+len, "write_mostly%s", sep);
2892 	if (test_bit(Blocked, &flags) ||
2893 	    (rdev->badblocks.unacked_exist
2894 	     && !test_bit(Faulty, &flags)))
2895 		len += sprintf(page+len, "blocked%s", sep);
2896 	if (!test_bit(Faulty, &flags) &&
2897 	    !test_bit(Journal, &flags) &&
2898 	    !test_bit(In_sync, &flags))
2899 		len += sprintf(page+len, "spare%s", sep);
2900 	if (test_bit(WriteErrorSeen, &flags))
2901 		len += sprintf(page+len, "write_error%s", sep);
2902 	if (test_bit(WantReplacement, &flags))
2903 		len += sprintf(page+len, "want_replacement%s", sep);
2904 	if (test_bit(Replacement, &flags))
2905 		len += sprintf(page+len, "replacement%s", sep);
2906 	if (test_bit(ExternalBbl, &flags))
2907 		len += sprintf(page+len, "external_bbl%s", sep);
2908 	if (test_bit(FailFast, &flags))
2909 		len += sprintf(page+len, "failfast%s", sep);
2910 
2911 	if (len)
2912 		len -= strlen(sep);
2913 
2914 	return len+sprintf(page+len, "\n");
2915 }
2916 
2917 static ssize_t
state_store(struct md_rdev * rdev,const char * buf,size_t len)2918 state_store(struct md_rdev *rdev, const char *buf, size_t len)
2919 {
2920 	/* can write
2921 	 *  faulty  - simulates an error
2922 	 *  remove  - disconnects the device
2923 	 *  writemostly - sets write_mostly
2924 	 *  -writemostly - clears write_mostly
2925 	 *  blocked - sets the Blocked flags
2926 	 *  -blocked - clears the Blocked and possibly simulates an error
2927 	 *  insync - sets Insync providing device isn't active
2928 	 *  -insync - clear Insync for a device with a slot assigned,
2929 	 *            so that it gets rebuilt based on bitmap
2930 	 *  write_error - sets WriteErrorSeen
2931 	 *  -write_error - clears WriteErrorSeen
2932 	 *  {,-}failfast - set/clear FailFast
2933 	 */
2934 
2935 	struct mddev *mddev = rdev->mddev;
2936 	int err = -EINVAL;
2937 	bool need_update_sb = false;
2938 
2939 	if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2940 		md_error(rdev->mddev, rdev);
2941 
2942 		if (test_bit(MD_BROKEN, &rdev->mddev->flags))
2943 			err = -EBUSY;
2944 		else
2945 			err = 0;
2946 	} else if (cmd_match(buf, "remove")) {
2947 		if (rdev->mddev->pers) {
2948 			clear_bit(Blocked, &rdev->flags);
2949 			remove_and_add_spares(rdev->mddev, rdev);
2950 		}
2951 		if (rdev->raid_disk >= 0)
2952 			err = -EBUSY;
2953 		else {
2954 			err = 0;
2955 			if (mddev_is_clustered(mddev))
2956 				err = mddev->cluster_ops->remove_disk(mddev, rdev);
2957 
2958 			if (err == 0) {
2959 				md_kick_rdev_from_array(rdev);
2960 				if (mddev->pers)
2961 					set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2962 				md_new_event();
2963 			}
2964 		}
2965 	} else if (cmd_match(buf, "writemostly")) {
2966 		set_bit(WriteMostly, &rdev->flags);
2967 		mddev_create_serial_pool(rdev->mddev, rdev);
2968 		need_update_sb = true;
2969 		err = 0;
2970 	} else if (cmd_match(buf, "-writemostly")) {
2971 		mddev_destroy_serial_pool(rdev->mddev, rdev);
2972 		clear_bit(WriteMostly, &rdev->flags);
2973 		need_update_sb = true;
2974 		err = 0;
2975 	} else if (cmd_match(buf, "blocked")) {
2976 		set_bit(Blocked, &rdev->flags);
2977 		err = 0;
2978 	} else if (cmd_match(buf, "-blocked")) {
2979 		if (!test_bit(Faulty, &rdev->flags) &&
2980 		    !test_bit(ExternalBbl, &rdev->flags) &&
2981 		    rdev->badblocks.unacked_exist) {
2982 			/* metadata handler doesn't understand badblocks,
2983 			 * so we need to fail the device
2984 			 */
2985 			md_error(rdev->mddev, rdev);
2986 		}
2987 		clear_bit(Blocked, &rdev->flags);
2988 		clear_bit(BlockedBadBlocks, &rdev->flags);
2989 		wake_up(&rdev->blocked_wait);
2990 		set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2991 
2992 		err = 0;
2993 	} else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
2994 		set_bit(In_sync, &rdev->flags);
2995 		err = 0;
2996 	} else if (cmd_match(buf, "failfast")) {
2997 		set_bit(FailFast, &rdev->flags);
2998 		need_update_sb = true;
2999 		err = 0;
3000 	} else if (cmd_match(buf, "-failfast")) {
3001 		clear_bit(FailFast, &rdev->flags);
3002 		need_update_sb = true;
3003 		err = 0;
3004 	} else if (cmd_match(buf, "-insync") && rdev->raid_disk >= 0 &&
3005 		   !test_bit(Journal, &rdev->flags)) {
3006 		if (rdev->mddev->pers == NULL) {
3007 			clear_bit(In_sync, &rdev->flags);
3008 			rdev->saved_raid_disk = rdev->raid_disk;
3009 			rdev->raid_disk = -1;
3010 			err = 0;
3011 		}
3012 	} else if (cmd_match(buf, "write_error")) {
3013 		set_bit(WriteErrorSeen, &rdev->flags);
3014 		err = 0;
3015 	} else if (cmd_match(buf, "-write_error")) {
3016 		clear_bit(WriteErrorSeen, &rdev->flags);
3017 		err = 0;
3018 	} else if (cmd_match(buf, "want_replacement")) {
3019 		/* Any non-spare device that is not a replacement can
3020 		 * become want_replacement at any time, but we then need to
3021 		 * check if recovery is needed.
3022 		 */
3023 		if (rdev->raid_disk >= 0 &&
3024 		    !test_bit(Journal, &rdev->flags) &&
3025 		    !test_bit(Replacement, &rdev->flags))
3026 			set_bit(WantReplacement, &rdev->flags);
3027 		set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
3028 		err = 0;
3029 	} else if (cmd_match(buf, "-want_replacement")) {
3030 		/* Clearing 'want_replacement' is always allowed.
3031 		 * Once replacements starts it is too late though.
3032 		 */
3033 		err = 0;
3034 		clear_bit(WantReplacement, &rdev->flags);
3035 	} else if (cmd_match(buf, "replacement")) {
3036 		/* Can only set a device as a replacement when array has not
3037 		 * yet been started.  Once running, replacement is automatic
3038 		 * from spares, or by assigning 'slot'.
3039 		 */
3040 		if (rdev->mddev->pers)
3041 			err = -EBUSY;
3042 		else {
3043 			set_bit(Replacement, &rdev->flags);
3044 			err = 0;
3045 		}
3046 	} else if (cmd_match(buf, "-replacement")) {
3047 		/* Similarly, can only clear Replacement before start */
3048 		if (rdev->mddev->pers)
3049 			err = -EBUSY;
3050 		else {
3051 			clear_bit(Replacement, &rdev->flags);
3052 			err = 0;
3053 		}
3054 	} else if (cmd_match(buf, "re-add")) {
3055 		if (!rdev->mddev->pers)
3056 			err = -EINVAL;
3057 		else if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) &&
3058 				rdev->saved_raid_disk >= 0) {
3059 			/* clear_bit is performed _after_ all the devices
3060 			 * have their local Faulty bit cleared. If any writes
3061 			 * happen in the meantime in the local node, they
3062 			 * will land in the local bitmap, which will be synced
3063 			 * by this node eventually
3064 			 */
3065 			if (!mddev_is_clustered(rdev->mddev) ||
3066 			    (err = mddev->cluster_ops->gather_bitmaps(rdev)) == 0) {
3067 				clear_bit(Faulty, &rdev->flags);
3068 				err = add_bound_rdev(rdev);
3069 			}
3070 		} else
3071 			err = -EBUSY;
3072 	} else if (cmd_match(buf, "external_bbl") && (rdev->mddev->external)) {
3073 		set_bit(ExternalBbl, &rdev->flags);
3074 		rdev->badblocks.shift = 0;
3075 		err = 0;
3076 	} else if (cmd_match(buf, "-external_bbl") && (rdev->mddev->external)) {
3077 		clear_bit(ExternalBbl, &rdev->flags);
3078 		err = 0;
3079 	}
3080 	if (need_update_sb)
3081 		md_update_sb(mddev, 1);
3082 	if (!err)
3083 		sysfs_notify_dirent_safe(rdev->sysfs_state);
3084 	return err ? err : len;
3085 }
3086 static struct rdev_sysfs_entry rdev_state =
3087 __ATTR_PREALLOC(state, S_IRUGO|S_IWUSR, state_show, state_store);
3088 
3089 static ssize_t
errors_show(struct md_rdev * rdev,char * page)3090 errors_show(struct md_rdev *rdev, char *page)
3091 {
3092 	return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
3093 }
3094 
3095 static ssize_t
errors_store(struct md_rdev * rdev,const char * buf,size_t len)3096 errors_store(struct md_rdev *rdev, const char *buf, size_t len)
3097 {
3098 	unsigned int n;
3099 	int rv;
3100 
3101 	rv = kstrtouint(buf, 10, &n);
3102 	if (rv < 0)
3103 		return rv;
3104 	atomic_set(&rdev->corrected_errors, n);
3105 	return len;
3106 }
3107 static struct rdev_sysfs_entry rdev_errors =
3108 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
3109 
3110 static ssize_t
slot_show(struct md_rdev * rdev,char * page)3111 slot_show(struct md_rdev *rdev, char *page)
3112 {
3113 	if (test_bit(Journal, &rdev->flags))
3114 		return sprintf(page, "journal\n");
3115 	else if (rdev->raid_disk < 0)
3116 		return sprintf(page, "none\n");
3117 	else
3118 		return sprintf(page, "%d\n", rdev->raid_disk);
3119 }
3120 
3121 static ssize_t
slot_store(struct md_rdev * rdev,const char * buf,size_t len)3122 slot_store(struct md_rdev *rdev, const char *buf, size_t len)
3123 {
3124 	int slot;
3125 	int err;
3126 
3127 	if (test_bit(Journal, &rdev->flags))
3128 		return -EBUSY;
3129 	if (strncmp(buf, "none", 4)==0)
3130 		slot = -1;
3131 	else {
3132 		err = kstrtouint(buf, 10, (unsigned int *)&slot);
3133 		if (err < 0)
3134 			return err;
3135 		if (slot < 0)
3136 			/* overflow */
3137 			return -ENOSPC;
3138 	}
3139 	if (rdev->mddev->pers && slot == -1) {
3140 		/* Setting 'slot' on an active array requires also
3141 		 * updating the 'rd%d' link, and communicating
3142 		 * with the personality with ->hot_*_disk.
3143 		 * For now we only support removing
3144 		 * failed/spare devices.  This normally happens automatically,
3145 		 * but not when the metadata is externally managed.
3146 		 */
3147 		if (rdev->raid_disk == -1)
3148 			return -EEXIST;
3149 		/* personality does all needed checks */
3150 		if (rdev->mddev->pers->hot_remove_disk == NULL)
3151 			return -EINVAL;
3152 		clear_bit(Blocked, &rdev->flags);
3153 		remove_and_add_spares(rdev->mddev, rdev);
3154 		if (rdev->raid_disk >= 0)
3155 			return -EBUSY;
3156 		set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
3157 	} else if (rdev->mddev->pers) {
3158 		/* Activating a spare .. or possibly reactivating
3159 		 * if we ever get bitmaps working here.
3160 		 */
3161 		int err;
3162 
3163 		if (rdev->raid_disk != -1)
3164 			return -EBUSY;
3165 
3166 		if (test_bit(MD_RECOVERY_RUNNING, &rdev->mddev->recovery))
3167 			return -EBUSY;
3168 
3169 		if (rdev->mddev->pers->hot_add_disk == NULL)
3170 			return -EINVAL;
3171 
3172 		if (slot >= rdev->mddev->raid_disks &&
3173 		    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
3174 			return -ENOSPC;
3175 
3176 		rdev->raid_disk = slot;
3177 		if (test_bit(In_sync, &rdev->flags))
3178 			rdev->saved_raid_disk = slot;
3179 		else
3180 			rdev->saved_raid_disk = -1;
3181 		clear_bit(In_sync, &rdev->flags);
3182 		clear_bit(Bitmap_sync, &rdev->flags);
3183 		err = rdev->mddev->pers->hot_add_disk(rdev->mddev, rdev);
3184 		if (err) {
3185 			rdev->raid_disk = -1;
3186 			return err;
3187 		} else
3188 			sysfs_notify_dirent_safe(rdev->sysfs_state);
3189 		/* failure here is OK */;
3190 		sysfs_link_rdev(rdev->mddev, rdev);
3191 		/* don't wakeup anyone, leave that to userspace. */
3192 	} else {
3193 		if (slot >= rdev->mddev->raid_disks &&
3194 		    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
3195 			return -ENOSPC;
3196 		rdev->raid_disk = slot;
3197 		/* assume it is working */
3198 		clear_bit(Faulty, &rdev->flags);
3199 		clear_bit(WriteMostly, &rdev->flags);
3200 		set_bit(In_sync, &rdev->flags);
3201 		sysfs_notify_dirent_safe(rdev->sysfs_state);
3202 	}
3203 	return len;
3204 }
3205 
3206 static struct rdev_sysfs_entry rdev_slot =
3207 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
3208 
3209 static ssize_t
offset_show(struct md_rdev * rdev,char * page)3210 offset_show(struct md_rdev *rdev, char *page)
3211 {
3212 	return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
3213 }
3214 
3215 static ssize_t
offset_store(struct md_rdev * rdev,const char * buf,size_t len)3216 offset_store(struct md_rdev *rdev, const char *buf, size_t len)
3217 {
3218 	unsigned long long offset;
3219 	if (kstrtoull(buf, 10, &offset) < 0)
3220 		return -EINVAL;
3221 	if (rdev->mddev->pers && rdev->raid_disk >= 0)
3222 		return -EBUSY;
3223 	if (rdev->sectors && rdev->mddev->external)
3224 		/* Must set offset before size, so overlap checks
3225 		 * can be sane */
3226 		return -EBUSY;
3227 	rdev->data_offset = offset;
3228 	rdev->new_data_offset = offset;
3229 	return len;
3230 }
3231 
3232 static struct rdev_sysfs_entry rdev_offset =
3233 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
3234 
new_offset_show(struct md_rdev * rdev,char * page)3235 static ssize_t new_offset_show(struct md_rdev *rdev, char *page)
3236 {
3237 	return sprintf(page, "%llu\n",
3238 		       (unsigned long long)rdev->new_data_offset);
3239 }
3240 
new_offset_store(struct md_rdev * rdev,const char * buf,size_t len)3241 static ssize_t new_offset_store(struct md_rdev *rdev,
3242 				const char *buf, size_t len)
3243 {
3244 	unsigned long long new_offset;
3245 	struct mddev *mddev = rdev->mddev;
3246 
3247 	if (kstrtoull(buf, 10, &new_offset) < 0)
3248 		return -EINVAL;
3249 
3250 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
3251 		return -EBUSY;
3252 	if (new_offset == rdev->data_offset)
3253 		/* reset is always permitted */
3254 		;
3255 	else if (new_offset > rdev->data_offset) {
3256 		/* must not push array size beyond rdev_sectors */
3257 		if (new_offset - rdev->data_offset
3258 		    + mddev->dev_sectors > rdev->sectors)
3259 				return -E2BIG;
3260 	}
3261 	/* Metadata worries about other space details. */
3262 
3263 	/* decreasing the offset is inconsistent with a backwards
3264 	 * reshape.
3265 	 */
3266 	if (new_offset < rdev->data_offset &&
3267 	    mddev->reshape_backwards)
3268 		return -EINVAL;
3269 	/* Increasing offset is inconsistent with forwards
3270 	 * reshape.  reshape_direction should be set to
3271 	 * 'backwards' first.
3272 	 */
3273 	if (new_offset > rdev->data_offset &&
3274 	    !mddev->reshape_backwards)
3275 		return -EINVAL;
3276 
3277 	if (mddev->pers && mddev->persistent &&
3278 	    !super_types[mddev->major_version]
3279 	    .allow_new_offset(rdev, new_offset))
3280 		return -E2BIG;
3281 	rdev->new_data_offset = new_offset;
3282 	if (new_offset > rdev->data_offset)
3283 		mddev->reshape_backwards = 1;
3284 	else if (new_offset < rdev->data_offset)
3285 		mddev->reshape_backwards = 0;
3286 
3287 	return len;
3288 }
3289 static struct rdev_sysfs_entry rdev_new_offset =
3290 __ATTR(new_offset, S_IRUGO|S_IWUSR, new_offset_show, new_offset_store);
3291 
3292 static ssize_t
rdev_size_show(struct md_rdev * rdev,char * page)3293 rdev_size_show(struct md_rdev *rdev, char *page)
3294 {
3295 	return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
3296 }
3297 
md_rdevs_overlap(struct md_rdev * a,struct md_rdev * b)3298 static int md_rdevs_overlap(struct md_rdev *a, struct md_rdev *b)
3299 {
3300 	/* check if two start/length pairs overlap */
3301 	if (a->data_offset + a->sectors <= b->data_offset)
3302 		return false;
3303 	if (b->data_offset + b->sectors <= a->data_offset)
3304 		return false;
3305 	return true;
3306 }
3307 
md_rdev_overlaps(struct md_rdev * rdev)3308 static bool md_rdev_overlaps(struct md_rdev *rdev)
3309 {
3310 	struct mddev *mddev;
3311 	struct md_rdev *rdev2;
3312 
3313 	spin_lock(&all_mddevs_lock);
3314 	list_for_each_entry(mddev, &all_mddevs, all_mddevs) {
3315 		if (test_bit(MD_DELETED, &mddev->flags))
3316 			continue;
3317 		rdev_for_each(rdev2, mddev) {
3318 			if (rdev != rdev2 && rdev->bdev == rdev2->bdev &&
3319 			    md_rdevs_overlap(rdev, rdev2)) {
3320 				spin_unlock(&all_mddevs_lock);
3321 				return true;
3322 			}
3323 		}
3324 	}
3325 	spin_unlock(&all_mddevs_lock);
3326 	return false;
3327 }
3328 
strict_blocks_to_sectors(const char * buf,sector_t * sectors)3329 static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
3330 {
3331 	unsigned long long blocks;
3332 	sector_t new;
3333 
3334 	if (kstrtoull(buf, 10, &blocks) < 0)
3335 		return -EINVAL;
3336 
3337 	if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
3338 		return -EINVAL; /* sector conversion overflow */
3339 
3340 	new = blocks * 2;
3341 	if (new != blocks * 2)
3342 		return -EINVAL; /* unsigned long long to sector_t overflow */
3343 
3344 	*sectors = new;
3345 	return 0;
3346 }
3347 
3348 static ssize_t
rdev_size_store(struct md_rdev * rdev,const char * buf,size_t len)3349 rdev_size_store(struct md_rdev *rdev, const char *buf, size_t len)
3350 {
3351 	struct mddev *my_mddev = rdev->mddev;
3352 	sector_t oldsectors = rdev->sectors;
3353 	sector_t sectors;
3354 
3355 	if (test_bit(Journal, &rdev->flags))
3356 		return -EBUSY;
3357 	if (strict_blocks_to_sectors(buf, &sectors) < 0)
3358 		return -EINVAL;
3359 	if (rdev->data_offset != rdev->new_data_offset)
3360 		return -EINVAL; /* too confusing */
3361 	if (my_mddev->pers && rdev->raid_disk >= 0) {
3362 		if (my_mddev->persistent) {
3363 			sectors = super_types[my_mddev->major_version].
3364 				rdev_size_change(rdev, sectors);
3365 			if (!sectors)
3366 				return -EBUSY;
3367 		} else if (!sectors)
3368 			sectors = bdev_nr_sectors(rdev->bdev) -
3369 				rdev->data_offset;
3370 		if (!my_mddev->pers->resize)
3371 			/* Cannot change size for RAID0 or Linear etc */
3372 			return -EINVAL;
3373 	}
3374 	if (sectors < my_mddev->dev_sectors)
3375 		return -EINVAL; /* component must fit device */
3376 
3377 	rdev->sectors = sectors;
3378 
3379 	/*
3380 	 * Check that all other rdevs with the same bdev do not overlap.  This
3381 	 * check does not provide a hard guarantee, it just helps avoid
3382 	 * dangerous mistakes.
3383 	 */
3384 	if (sectors > oldsectors && my_mddev->external &&
3385 	    md_rdev_overlaps(rdev)) {
3386 		/*
3387 		 * Someone else could have slipped in a size change here, but
3388 		 * doing so is just silly.  We put oldsectors back because we
3389 		 * know it is safe, and trust userspace not to race with itself.
3390 		 */
3391 		rdev->sectors = oldsectors;
3392 		return -EBUSY;
3393 	}
3394 	return len;
3395 }
3396 
3397 static struct rdev_sysfs_entry rdev_size =
3398 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
3399 
recovery_start_show(struct md_rdev * rdev,char * page)3400 static ssize_t recovery_start_show(struct md_rdev *rdev, char *page)
3401 {
3402 	unsigned long long recovery_start = rdev->recovery_offset;
3403 
3404 	if (test_bit(In_sync, &rdev->flags) ||
3405 	    recovery_start == MaxSector)
3406 		return sprintf(page, "none\n");
3407 
3408 	return sprintf(page, "%llu\n", recovery_start);
3409 }
3410 
recovery_start_store(struct md_rdev * rdev,const char * buf,size_t len)3411 static ssize_t recovery_start_store(struct md_rdev *rdev, const char *buf, size_t len)
3412 {
3413 	unsigned long long recovery_start;
3414 
3415 	if (cmd_match(buf, "none"))
3416 		recovery_start = MaxSector;
3417 	else if (kstrtoull(buf, 10, &recovery_start))
3418 		return -EINVAL;
3419 
3420 	if (rdev->mddev->pers &&
3421 	    rdev->raid_disk >= 0)
3422 		return -EBUSY;
3423 
3424 	rdev->recovery_offset = recovery_start;
3425 	if (recovery_start == MaxSector)
3426 		set_bit(In_sync, &rdev->flags);
3427 	else
3428 		clear_bit(In_sync, &rdev->flags);
3429 	return len;
3430 }
3431 
3432 static struct rdev_sysfs_entry rdev_recovery_start =
3433 __ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store);
3434 
3435 /* sysfs access to bad-blocks list.
3436  * We present two files.
3437  * 'bad-blocks' lists sector numbers and lengths of ranges that
3438  *    are recorded as bad.  The list is truncated to fit within
3439  *    the one-page limit of sysfs.
3440  *    Writing "sector length" to this file adds an acknowledged
3441  *    bad block list.
3442  * 'unacknowledged-bad-blocks' lists bad blocks that have not yet
3443  *    been acknowledged.  Writing to this file adds bad blocks
3444  *    without acknowledging them.  This is largely for testing.
3445  */
bb_show(struct md_rdev * rdev,char * page)3446 static ssize_t bb_show(struct md_rdev *rdev, char *page)
3447 {
3448 	return badblocks_show(&rdev->badblocks, page, 0);
3449 }
bb_store(struct md_rdev * rdev,const char * page,size_t len)3450 static ssize_t bb_store(struct md_rdev *rdev, const char *page, size_t len)
3451 {
3452 	int rv = badblocks_store(&rdev->badblocks, page, len, 0);
3453 	/* Maybe that ack was all we needed */
3454 	if (test_and_clear_bit(BlockedBadBlocks, &rdev->flags))
3455 		wake_up(&rdev->blocked_wait);
3456 	return rv;
3457 }
3458 static struct rdev_sysfs_entry rdev_bad_blocks =
3459 __ATTR(bad_blocks, S_IRUGO|S_IWUSR, bb_show, bb_store);
3460 
ubb_show(struct md_rdev * rdev,char * page)3461 static ssize_t ubb_show(struct md_rdev *rdev, char *page)
3462 {
3463 	return badblocks_show(&rdev->badblocks, page, 1);
3464 }
ubb_store(struct md_rdev * rdev,const char * page,size_t len)3465 static ssize_t ubb_store(struct md_rdev *rdev, const char *page, size_t len)
3466 {
3467 	return badblocks_store(&rdev->badblocks, page, len, 1);
3468 }
3469 static struct rdev_sysfs_entry rdev_unack_bad_blocks =
3470 __ATTR(unacknowledged_bad_blocks, S_IRUGO|S_IWUSR, ubb_show, ubb_store);
3471 
3472 static ssize_t
ppl_sector_show(struct md_rdev * rdev,char * page)3473 ppl_sector_show(struct md_rdev *rdev, char *page)
3474 {
3475 	return sprintf(page, "%llu\n", (unsigned long long)rdev->ppl.sector);
3476 }
3477 
3478 static ssize_t
ppl_sector_store(struct md_rdev * rdev,const char * buf,size_t len)3479 ppl_sector_store(struct md_rdev *rdev, const char *buf, size_t len)
3480 {
3481 	unsigned long long sector;
3482 
3483 	if (kstrtoull(buf, 10, &sector) < 0)
3484 		return -EINVAL;
3485 	if (sector != (sector_t)sector)
3486 		return -EINVAL;
3487 
3488 	if (rdev->mddev->pers && test_bit(MD_HAS_PPL, &rdev->mddev->flags) &&
3489 	    rdev->raid_disk >= 0)
3490 		return -EBUSY;
3491 
3492 	if (rdev->mddev->persistent) {
3493 		if (rdev->mddev->major_version == 0)
3494 			return -EINVAL;
3495 		if ((sector > rdev->sb_start &&
3496 		     sector - rdev->sb_start > S16_MAX) ||
3497 		    (sector < rdev->sb_start &&
3498 		     rdev->sb_start - sector > -S16_MIN))
3499 			return -EINVAL;
3500 		rdev->ppl.offset = sector - rdev->sb_start;
3501 	} else if (!rdev->mddev->external) {
3502 		return -EBUSY;
3503 	}
3504 	rdev->ppl.sector = sector;
3505 	return len;
3506 }
3507 
3508 static struct rdev_sysfs_entry rdev_ppl_sector =
3509 __ATTR(ppl_sector, S_IRUGO|S_IWUSR, ppl_sector_show, ppl_sector_store);
3510 
3511 static ssize_t
ppl_size_show(struct md_rdev * rdev,char * page)3512 ppl_size_show(struct md_rdev *rdev, char *page)
3513 {
3514 	return sprintf(page, "%u\n", rdev->ppl.size);
3515 }
3516 
3517 static ssize_t
ppl_size_store(struct md_rdev * rdev,const char * buf,size_t len)3518 ppl_size_store(struct md_rdev *rdev, const char *buf, size_t len)
3519 {
3520 	unsigned int size;
3521 
3522 	if (kstrtouint(buf, 10, &size) < 0)
3523 		return -EINVAL;
3524 
3525 	if (rdev->mddev->pers && test_bit(MD_HAS_PPL, &rdev->mddev->flags) &&
3526 	    rdev->raid_disk >= 0)
3527 		return -EBUSY;
3528 
3529 	if (rdev->mddev->persistent) {
3530 		if (rdev->mddev->major_version == 0)
3531 			return -EINVAL;
3532 		if (size > U16_MAX)
3533 			return -EINVAL;
3534 	} else if (!rdev->mddev->external) {
3535 		return -EBUSY;
3536 	}
3537 	rdev->ppl.size = size;
3538 	return len;
3539 }
3540 
3541 static struct rdev_sysfs_entry rdev_ppl_size =
3542 __ATTR(ppl_size, S_IRUGO|S_IWUSR, ppl_size_show, ppl_size_store);
3543 
3544 static struct attribute *rdev_default_attrs[] = {
3545 	&rdev_state.attr,
3546 	&rdev_errors.attr,
3547 	&rdev_slot.attr,
3548 	&rdev_offset.attr,
3549 	&rdev_new_offset.attr,
3550 	&rdev_size.attr,
3551 	&rdev_recovery_start.attr,
3552 	&rdev_bad_blocks.attr,
3553 	&rdev_unack_bad_blocks.attr,
3554 	&rdev_ppl_sector.attr,
3555 	&rdev_ppl_size.attr,
3556 	NULL,
3557 };
3558 ATTRIBUTE_GROUPS(rdev_default);
3559 static ssize_t
rdev_attr_show(struct kobject * kobj,struct attribute * attr,char * page)3560 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3561 {
3562 	struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3563 	struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3564 
3565 	if (!entry->show)
3566 		return -EIO;
3567 	if (!rdev->mddev)
3568 		return -ENODEV;
3569 	return entry->show(rdev, page);
3570 }
3571 
3572 static ssize_t
rdev_attr_store(struct kobject * kobj,struct attribute * attr,const char * page,size_t length)3573 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
3574 	      const char *page, size_t length)
3575 {
3576 	struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3577 	struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3578 	struct kernfs_node *kn = NULL;
3579 	bool suspend = false;
3580 	ssize_t rv;
3581 	struct mddev *mddev = READ_ONCE(rdev->mddev);
3582 
3583 	if (!entry->store)
3584 		return -EIO;
3585 	if (!capable(CAP_SYS_ADMIN))
3586 		return -EACCES;
3587 	if (!mddev)
3588 		return -ENODEV;
3589 
3590 	if (entry->store == state_store) {
3591 		if (cmd_match(page, "remove"))
3592 			kn = sysfs_break_active_protection(kobj, attr);
3593 		if (cmd_match(page, "remove") || cmd_match(page, "re-add") ||
3594 		    cmd_match(page, "writemostly") ||
3595 		    cmd_match(page, "-writemostly"))
3596 			suspend = true;
3597 	}
3598 
3599 	rv = suspend ? mddev_suspend_and_lock(mddev) : mddev_lock(mddev);
3600 	if (!rv) {
3601 		if (rdev->mddev == NULL)
3602 			rv = -ENODEV;
3603 		else
3604 			rv = entry->store(rdev, page, length);
3605 		suspend ? mddev_unlock_and_resume(mddev) : mddev_unlock(mddev);
3606 	}
3607 
3608 	if (kn)
3609 		sysfs_unbreak_active_protection(kn);
3610 
3611 	return rv;
3612 }
3613 
rdev_free(struct kobject * ko)3614 static void rdev_free(struct kobject *ko)
3615 {
3616 	struct md_rdev *rdev = container_of(ko, struct md_rdev, kobj);
3617 	kfree(rdev);
3618 }
3619 static const struct sysfs_ops rdev_sysfs_ops = {
3620 	.show		= rdev_attr_show,
3621 	.store		= rdev_attr_store,
3622 };
3623 static const struct kobj_type rdev_ktype = {
3624 	.release	= rdev_free,
3625 	.sysfs_ops	= &rdev_sysfs_ops,
3626 	.default_groups	= rdev_default_groups,
3627 };
3628 
md_rdev_init(struct md_rdev * rdev)3629 int md_rdev_init(struct md_rdev *rdev)
3630 {
3631 	rdev->desc_nr = -1;
3632 	rdev->saved_raid_disk = -1;
3633 	rdev->raid_disk = -1;
3634 	rdev->flags = 0;
3635 	rdev->data_offset = 0;
3636 	rdev->new_data_offset = 0;
3637 	rdev->sb_events = 0;
3638 	rdev->last_read_error = 0;
3639 	rdev->sb_loaded = 0;
3640 	rdev->bb_page = NULL;
3641 	atomic_set(&rdev->nr_pending, 0);
3642 	atomic_set(&rdev->read_errors, 0);
3643 	atomic_set(&rdev->corrected_errors, 0);
3644 
3645 	INIT_LIST_HEAD(&rdev->same_set);
3646 	init_waitqueue_head(&rdev->blocked_wait);
3647 
3648 	/* Add space to store bad block list.
3649 	 * This reserves the space even on arrays where it cannot
3650 	 * be used - I wonder if that matters
3651 	 */
3652 	return badblocks_init(&rdev->badblocks, 0);
3653 }
3654 EXPORT_SYMBOL_GPL(md_rdev_init);
3655 
3656 /*
3657  * Import a device. If 'super_format' >= 0, then sanity check the superblock
3658  *
3659  * mark the device faulty if:
3660  *
3661  *   - the device is nonexistent (zero size)
3662  *   - the device has no valid superblock
3663  *
3664  * a faulty rdev _never_ has rdev->sb set.
3665  */
md_import_device(dev_t newdev,int super_format,int super_minor)3666 static struct md_rdev *md_import_device(dev_t newdev, int super_format, int super_minor)
3667 {
3668 	struct md_rdev *rdev;
3669 	sector_t size;
3670 	int err;
3671 
3672 	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
3673 	if (!rdev)
3674 		return ERR_PTR(-ENOMEM);
3675 
3676 	err = md_rdev_init(rdev);
3677 	if (err)
3678 		goto out_free_rdev;
3679 	err = alloc_disk_sb(rdev);
3680 	if (err)
3681 		goto out_clear_rdev;
3682 
3683 	rdev->bdev_file = bdev_file_open_by_dev(newdev,
3684 			BLK_OPEN_READ | BLK_OPEN_WRITE,
3685 			super_format == -2 ? &claim_rdev : rdev, NULL);
3686 	if (IS_ERR(rdev->bdev_file)) {
3687 		pr_warn("md: could not open device unknown-block(%u,%u).\n",
3688 			MAJOR(newdev), MINOR(newdev));
3689 		err = PTR_ERR(rdev->bdev_file);
3690 		goto out_clear_rdev;
3691 	}
3692 	rdev->bdev = file_bdev(rdev->bdev_file);
3693 
3694 	kobject_init(&rdev->kobj, &rdev_ktype);
3695 
3696 	size = bdev_nr_bytes(rdev->bdev) >> BLOCK_SIZE_BITS;
3697 	if (!size) {
3698 		pr_warn("md: %pg has zero or unknown size, marking faulty!\n",
3699 			rdev->bdev);
3700 		err = -EINVAL;
3701 		goto out_blkdev_put;
3702 	}
3703 
3704 	if (super_format >= 0) {
3705 		err = super_types[super_format].
3706 			load_super(rdev, NULL, super_minor);
3707 		if (err == -EINVAL) {
3708 			pr_warn("md: %pg does not have a valid v%d.%d superblock, not importing!\n",
3709 				rdev->bdev,
3710 				super_format, super_minor);
3711 			goto out_blkdev_put;
3712 		}
3713 		if (err < 0) {
3714 			pr_warn("md: could not read %pg's sb, not importing!\n",
3715 				rdev->bdev);
3716 			goto out_blkdev_put;
3717 		}
3718 	}
3719 
3720 	return rdev;
3721 
3722 out_blkdev_put:
3723 	fput(rdev->bdev_file);
3724 out_clear_rdev:
3725 	md_rdev_clear(rdev);
3726 out_free_rdev:
3727 	kfree(rdev);
3728 	return ERR_PTR(err);
3729 }
3730 
3731 /*
3732  * Check a full RAID array for plausibility
3733  */
3734 
analyze_sbs(struct mddev * mddev)3735 static int analyze_sbs(struct mddev *mddev)
3736 {
3737 	int i;
3738 	struct md_rdev *rdev, *freshest, *tmp;
3739 
3740 	freshest = NULL;
3741 	rdev_for_each_safe(rdev, tmp, mddev)
3742 		switch (super_types[mddev->major_version].
3743 			load_super(rdev, freshest, mddev->minor_version)) {
3744 		case 1:
3745 			freshest = rdev;
3746 			break;
3747 		case 0:
3748 			break;
3749 		default:
3750 			pr_warn("md: fatal superblock inconsistency in %pg -- removing from array\n",
3751 				rdev->bdev);
3752 			md_kick_rdev_from_array(rdev);
3753 		}
3754 
3755 	/* Cannot find a valid fresh disk */
3756 	if (!freshest) {
3757 		pr_warn("md: cannot find a valid disk\n");
3758 		return -EINVAL;
3759 	}
3760 
3761 	super_types[mddev->major_version].
3762 		validate_super(mddev, NULL/*freshest*/, freshest);
3763 
3764 	i = 0;
3765 	rdev_for_each_safe(rdev, tmp, mddev) {
3766 		if (mddev->max_disks &&
3767 		    (rdev->desc_nr >= mddev->max_disks ||
3768 		     i > mddev->max_disks)) {
3769 			pr_warn("md: %s: %pg: only %d devices permitted\n",
3770 				mdname(mddev), rdev->bdev,
3771 				mddev->max_disks);
3772 			md_kick_rdev_from_array(rdev);
3773 			continue;
3774 		}
3775 		if (rdev != freshest) {
3776 			if (super_types[mddev->major_version].
3777 			    validate_super(mddev, freshest, rdev)) {
3778 				pr_warn("md: kicking non-fresh %pg from array!\n",
3779 					rdev->bdev);
3780 				md_kick_rdev_from_array(rdev);
3781 				continue;
3782 			}
3783 		}
3784 		if (rdev->raid_disk >= (mddev->raid_disks - min(0, mddev->delta_disks)) &&
3785 		    !test_bit(Journal, &rdev->flags)) {
3786 			rdev->raid_disk = -1;
3787 			clear_bit(In_sync, &rdev->flags);
3788 		}
3789 	}
3790 
3791 	return 0;
3792 }
3793 
3794 /* Read a fixed-point number.
3795  * Numbers in sysfs attributes should be in "standard" units where
3796  * possible, so time should be in seconds.
3797  * However we internally use a a much smaller unit such as
3798  * milliseconds or jiffies.
3799  * This function takes a decimal number with a possible fractional
3800  * component, and produces an integer which is the result of
3801  * multiplying that number by 10^'scale'.
3802  * all without any floating-point arithmetic.
3803  */
strict_strtoul_scaled(const char * cp,unsigned long * res,int scale)3804 int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale)
3805 {
3806 	unsigned long result = 0;
3807 	long decimals = -1;
3808 	while (isdigit(*cp) || (*cp == '.' && decimals < 0)) {
3809 		if (*cp == '.')
3810 			decimals = 0;
3811 		else if (decimals < scale) {
3812 			unsigned int value;
3813 			value = *cp - '0';
3814 			result = result * 10 + value;
3815 			if (decimals >= 0)
3816 				decimals++;
3817 		}
3818 		cp++;
3819 	}
3820 	if (*cp == '\n')
3821 		cp++;
3822 	if (*cp)
3823 		return -EINVAL;
3824 	if (decimals < 0)
3825 		decimals = 0;
3826 	*res = result * int_pow(10, scale - decimals);
3827 	return 0;
3828 }
3829 
3830 static ssize_t
safe_delay_show(struct mddev * mddev,char * page)3831 safe_delay_show(struct mddev *mddev, char *page)
3832 {
3833 	unsigned int msec = ((unsigned long)mddev->safemode_delay*1000)/HZ;
3834 
3835 	return sprintf(page, "%u.%03u\n", msec/1000, msec%1000);
3836 }
3837 static ssize_t
safe_delay_store(struct mddev * mddev,const char * cbuf,size_t len)3838 safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
3839 {
3840 	unsigned long msec;
3841 
3842 	if (mddev_is_clustered(mddev)) {
3843 		pr_warn("md: Safemode is disabled for clustered mode\n");
3844 		return -EINVAL;
3845 	}
3846 
3847 	if (strict_strtoul_scaled(cbuf, &msec, 3) < 0 || msec > UINT_MAX / HZ)
3848 		return -EINVAL;
3849 	if (msec == 0)
3850 		mddev->safemode_delay = 0;
3851 	else {
3852 		unsigned long old_delay = mddev->safemode_delay;
3853 		unsigned long new_delay = (msec*HZ)/1000;
3854 
3855 		if (new_delay == 0)
3856 			new_delay = 1;
3857 		mddev->safemode_delay = new_delay;
3858 		if (new_delay < old_delay || old_delay == 0)
3859 			mod_timer(&mddev->safemode_timer, jiffies+1);
3860 	}
3861 	return len;
3862 }
3863 static struct md_sysfs_entry md_safe_delay =
3864 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
3865 
3866 static ssize_t
level_show(struct mddev * mddev,char * page)3867 level_show(struct mddev *mddev, char *page)
3868 {
3869 	struct md_personality *p;
3870 	int ret;
3871 	spin_lock(&mddev->lock);
3872 	p = mddev->pers;
3873 	if (p)
3874 		ret = sprintf(page, "%s\n", p->head.name);
3875 	else if (mddev->clevel[0])
3876 		ret = sprintf(page, "%s\n", mddev->clevel);
3877 	else if (mddev->level != LEVEL_NONE)
3878 		ret = sprintf(page, "%d\n", mddev->level);
3879 	else
3880 		ret = 0;
3881 	spin_unlock(&mddev->lock);
3882 	return ret;
3883 }
3884 
3885 static ssize_t
level_store(struct mddev * mddev,const char * buf,size_t len)3886 level_store(struct mddev *mddev, const char *buf, size_t len)
3887 {
3888 	char clevel[16];
3889 	ssize_t rv;
3890 	size_t slen = len;
3891 	struct md_personality *pers, *oldpers;
3892 	long level;
3893 	void *priv, *oldpriv;
3894 	struct md_rdev *rdev;
3895 
3896 	if (slen == 0 || slen >= sizeof(clevel))
3897 		return -EINVAL;
3898 
3899 	rv = mddev_suspend_and_lock(mddev);
3900 	if (rv)
3901 		return rv;
3902 
3903 	if (mddev->pers == NULL) {
3904 		memcpy(mddev->clevel, buf, slen);
3905 		if (mddev->clevel[slen-1] == '\n')
3906 			slen--;
3907 		mddev->clevel[slen] = 0;
3908 		mddev->level = LEVEL_NONE;
3909 		rv = len;
3910 		goto out_unlock;
3911 	}
3912 	rv = -EROFS;
3913 	if (!md_is_rdwr(mddev))
3914 		goto out_unlock;
3915 
3916 	/* request to change the personality.  Need to ensure:
3917 	 *  - array is not engaged in resync/recovery/reshape
3918 	 *  - old personality can be suspended
3919 	 *  - new personality will access other array.
3920 	 */
3921 
3922 	rv = -EBUSY;
3923 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3924 	    mddev->reshape_position != MaxSector ||
3925 	    mddev->sysfs_active)
3926 		goto out_unlock;
3927 
3928 	rv = -EINVAL;
3929 	if (!mddev->pers->quiesce) {
3930 		pr_warn("md: %s: %s does not support online personality change\n",
3931 			mdname(mddev), mddev->pers->head.name);
3932 		goto out_unlock;
3933 	}
3934 
3935 	/* Now find the new personality */
3936 	memcpy(clevel, buf, slen);
3937 	if (clevel[slen-1] == '\n')
3938 		slen--;
3939 	clevel[slen] = 0;
3940 	if (kstrtol(clevel, 10, &level))
3941 		level = LEVEL_NONE;
3942 
3943 	if (request_module("md-%s", clevel) != 0)
3944 		request_module("md-level-%s", clevel);
3945 	pers = get_pers(level, clevel);
3946 	if (!pers) {
3947 		rv = -EINVAL;
3948 		goto out_unlock;
3949 	}
3950 
3951 	if (pers == mddev->pers) {
3952 		/* Nothing to do! */
3953 		put_pers(pers);
3954 		rv = len;
3955 		goto out_unlock;
3956 	}
3957 	if (!pers->takeover) {
3958 		put_pers(pers);
3959 		pr_warn("md: %s: %s does not support personality takeover\n",
3960 			mdname(mddev), clevel);
3961 		rv = -EINVAL;
3962 		goto out_unlock;
3963 	}
3964 
3965 	rdev_for_each(rdev, mddev)
3966 		rdev->new_raid_disk = rdev->raid_disk;
3967 
3968 	/* ->takeover must set new_* and/or delta_disks
3969 	 * if it succeeds, and may set them when it fails.
3970 	 */
3971 	priv = pers->takeover(mddev);
3972 	if (IS_ERR(priv)) {
3973 		mddev->new_level = mddev->level;
3974 		mddev->new_layout = mddev->layout;
3975 		mddev->new_chunk_sectors = mddev->chunk_sectors;
3976 		mddev->raid_disks -= mddev->delta_disks;
3977 		mddev->delta_disks = 0;
3978 		mddev->reshape_backwards = 0;
3979 		put_pers(pers);
3980 		pr_warn("md: %s: %s would not accept array\n",
3981 			mdname(mddev), clevel);
3982 		rv = PTR_ERR(priv);
3983 		goto out_unlock;
3984 	}
3985 
3986 	/* Looks like we have a winner */
3987 	mddev_detach(mddev);
3988 
3989 	spin_lock(&mddev->lock);
3990 	oldpers = mddev->pers;
3991 	oldpriv = mddev->private;
3992 	mddev->pers = pers;
3993 	mddev->private = priv;
3994 	strscpy(mddev->clevel, pers->head.name, sizeof(mddev->clevel));
3995 	mddev->level = mddev->new_level;
3996 	mddev->layout = mddev->new_layout;
3997 	mddev->chunk_sectors = mddev->new_chunk_sectors;
3998 	mddev->delta_disks = 0;
3999 	mddev->reshape_backwards = 0;
4000 	mddev->degraded = 0;
4001 	spin_unlock(&mddev->lock);
4002 
4003 	if (oldpers->sync_request == NULL &&
4004 	    mddev->external) {
4005 		/* We are converting from a no-redundancy array
4006 		 * to a redundancy array and metadata is managed
4007 		 * externally so we need to be sure that writes
4008 		 * won't block due to a need to transition
4009 		 *      clean->dirty
4010 		 * until external management is started.
4011 		 */
4012 		mddev->in_sync = 0;
4013 		mddev->safemode_delay = 0;
4014 		mddev->safemode = 0;
4015 	}
4016 
4017 	oldpers->free(mddev, oldpriv);
4018 
4019 	if (oldpers->sync_request == NULL &&
4020 	    pers->sync_request != NULL) {
4021 		/* need to add the md_redundancy_group */
4022 		if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
4023 			pr_warn("md: cannot register extra attributes for %s\n",
4024 				mdname(mddev));
4025 		mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action");
4026 		mddev->sysfs_completed = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_completed");
4027 		mddev->sysfs_degraded = sysfs_get_dirent_safe(mddev->kobj.sd, "degraded");
4028 	}
4029 	if (oldpers->sync_request != NULL &&
4030 	    pers->sync_request == NULL) {
4031 		/* need to remove the md_redundancy_group */
4032 		if (mddev->to_remove == NULL)
4033 			mddev->to_remove = &md_redundancy_group;
4034 	}
4035 
4036 	put_pers(oldpers);
4037 
4038 	rdev_for_each(rdev, mddev) {
4039 		if (rdev->raid_disk < 0)
4040 			continue;
4041 		if (rdev->new_raid_disk >= mddev->raid_disks)
4042 			rdev->new_raid_disk = -1;
4043 		if (rdev->new_raid_disk == rdev->raid_disk)
4044 			continue;
4045 		sysfs_unlink_rdev(mddev, rdev);
4046 	}
4047 	rdev_for_each(rdev, mddev) {
4048 		if (rdev->raid_disk < 0)
4049 			continue;
4050 		if (rdev->new_raid_disk == rdev->raid_disk)
4051 			continue;
4052 		rdev->raid_disk = rdev->new_raid_disk;
4053 		if (rdev->raid_disk < 0)
4054 			clear_bit(In_sync, &rdev->flags);
4055 		else {
4056 			if (sysfs_link_rdev(mddev, rdev))
4057 				pr_warn("md: cannot register rd%d for %s after level change\n",
4058 					rdev->raid_disk, mdname(mddev));
4059 		}
4060 	}
4061 
4062 	if (pers->sync_request == NULL) {
4063 		/* this is now an array without redundancy, so
4064 		 * it must always be in_sync
4065 		 */
4066 		mddev->in_sync = 1;
4067 		del_timer_sync(&mddev->safemode_timer);
4068 	}
4069 	pers->run(mddev);
4070 	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
4071 	if (!mddev->thread)
4072 		md_update_sb(mddev, 1);
4073 	sysfs_notify_dirent_safe(mddev->sysfs_level);
4074 	md_new_event();
4075 	rv = len;
4076 out_unlock:
4077 	mddev_unlock_and_resume(mddev);
4078 	return rv;
4079 }
4080 
4081 static struct md_sysfs_entry md_level =
4082 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
4083 
4084 static ssize_t
new_level_show(struct mddev * mddev,char * page)4085 new_level_show(struct mddev *mddev, char *page)
4086 {
4087 	return sprintf(page, "%d\n", mddev->new_level);
4088 }
4089 
4090 static ssize_t
new_level_store(struct mddev * mddev,const char * buf,size_t len)4091 new_level_store(struct mddev *mddev, const char *buf, size_t len)
4092 {
4093 	unsigned int n;
4094 	int err;
4095 
4096 	err = kstrtouint(buf, 10, &n);
4097 	if (err < 0)
4098 		return err;
4099 	err = mddev_lock(mddev);
4100 	if (err)
4101 		return err;
4102 
4103 	mddev->new_level = n;
4104 	md_update_sb(mddev, 1);
4105 
4106 	mddev_unlock(mddev);
4107 	return len;
4108 }
4109 static struct md_sysfs_entry md_new_level =
4110 __ATTR(new_level, 0664, new_level_show, new_level_store);
4111 
4112 static ssize_t
layout_show(struct mddev * mddev,char * page)4113 layout_show(struct mddev *mddev, char *page)
4114 {
4115 	/* just a number, not meaningful for all levels */
4116 	if (mddev->reshape_position != MaxSector &&
4117 	    mddev->layout != mddev->new_layout)
4118 		return sprintf(page, "%d (%d)\n",
4119 			       mddev->new_layout, mddev->layout);
4120 	return sprintf(page, "%d\n", mddev->layout);
4121 }
4122 
4123 static ssize_t
layout_store(struct mddev * mddev,const char * buf,size_t len)4124 layout_store(struct mddev *mddev, const char *buf, size_t len)
4125 {
4126 	unsigned int n;
4127 	int err;
4128 
4129 	err = kstrtouint(buf, 10, &n);
4130 	if (err < 0)
4131 		return err;
4132 	err = mddev_lock(mddev);
4133 	if (err)
4134 		return err;
4135 
4136 	if (mddev->pers) {
4137 		if (mddev->pers->check_reshape == NULL)
4138 			err = -EBUSY;
4139 		else if (!md_is_rdwr(mddev))
4140 			err = -EROFS;
4141 		else {
4142 			mddev->new_layout = n;
4143 			err = mddev->pers->check_reshape(mddev);
4144 			if (err)
4145 				mddev->new_layout = mddev->layout;
4146 		}
4147 	} else {
4148 		mddev->new_layout = n;
4149 		if (mddev->reshape_position == MaxSector)
4150 			mddev->layout = n;
4151 	}
4152 	mddev_unlock(mddev);
4153 	return err ?: len;
4154 }
4155 static struct md_sysfs_entry md_layout =
4156 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
4157 
4158 static ssize_t
raid_disks_show(struct mddev * mddev,char * page)4159 raid_disks_show(struct mddev *mddev, char *page)
4160 {
4161 	if (mddev->raid_disks == 0)
4162 		return 0;
4163 	if (mddev->reshape_position != MaxSector &&
4164 	    mddev->delta_disks != 0)
4165 		return sprintf(page, "%d (%d)\n", mddev->raid_disks,
4166 			       mddev->raid_disks - mddev->delta_disks);
4167 	return sprintf(page, "%d\n", mddev->raid_disks);
4168 }
4169 
4170 static int update_raid_disks(struct mddev *mddev, int raid_disks);
4171 
4172 static ssize_t
raid_disks_store(struct mddev * mddev,const char * buf,size_t len)4173 raid_disks_store(struct mddev *mddev, const char *buf, size_t len)
4174 {
4175 	unsigned int n;
4176 	int err;
4177 
4178 	err = kstrtouint(buf, 10, &n);
4179 	if (err < 0)
4180 		return err;
4181 
4182 	err = mddev_lock(mddev);
4183 	if (err)
4184 		return err;
4185 	if (mddev->pers)
4186 		err = update_raid_disks(mddev, n);
4187 	else if (mddev->reshape_position != MaxSector) {
4188 		struct md_rdev *rdev;
4189 		int olddisks = mddev->raid_disks - mddev->delta_disks;
4190 
4191 		err = -EINVAL;
4192 		rdev_for_each(rdev, mddev) {
4193 			if (olddisks < n &&
4194 			    rdev->data_offset < rdev->new_data_offset)
4195 				goto out_unlock;
4196 			if (olddisks > n &&
4197 			    rdev->data_offset > rdev->new_data_offset)
4198 				goto out_unlock;
4199 		}
4200 		err = 0;
4201 		mddev->delta_disks = n - olddisks;
4202 		mddev->raid_disks = n;
4203 		mddev->reshape_backwards = (mddev->delta_disks < 0);
4204 	} else
4205 		mddev->raid_disks = n;
4206 out_unlock:
4207 	mddev_unlock(mddev);
4208 	return err ? err : len;
4209 }
4210 static struct md_sysfs_entry md_raid_disks =
4211 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
4212 
4213 static ssize_t
uuid_show(struct mddev * mddev,char * page)4214 uuid_show(struct mddev *mddev, char *page)
4215 {
4216 	return sprintf(page, "%pU\n", mddev->uuid);
4217 }
4218 static struct md_sysfs_entry md_uuid =
4219 __ATTR(uuid, S_IRUGO, uuid_show, NULL);
4220 
4221 static ssize_t
chunk_size_show(struct mddev * mddev,char * page)4222 chunk_size_show(struct mddev *mddev, char *page)
4223 {
4224 	if (mddev->reshape_position != MaxSector &&
4225 	    mddev->chunk_sectors != mddev->new_chunk_sectors)
4226 		return sprintf(page, "%d (%d)\n",
4227 			       mddev->new_chunk_sectors << 9,
4228 			       mddev->chunk_sectors << 9);
4229 	return sprintf(page, "%d\n", mddev->chunk_sectors << 9);
4230 }
4231 
4232 static ssize_t
chunk_size_store(struct mddev * mddev,const char * buf,size_t len)4233 chunk_size_store(struct mddev *mddev, const char *buf, size_t len)
4234 {
4235 	unsigned long n;
4236 	int err;
4237 
4238 	err = kstrtoul(buf, 10, &n);
4239 	if (err < 0)
4240 		return err;
4241 
4242 	err = mddev_lock(mddev);
4243 	if (err)
4244 		return err;
4245 	if (mddev->pers) {
4246 		if (mddev->pers->check_reshape == NULL)
4247 			err = -EBUSY;
4248 		else if (!md_is_rdwr(mddev))
4249 			err = -EROFS;
4250 		else {
4251 			mddev->new_chunk_sectors = n >> 9;
4252 			err = mddev->pers->check_reshape(mddev);
4253 			if (err)
4254 				mddev->new_chunk_sectors = mddev->chunk_sectors;
4255 		}
4256 	} else {
4257 		mddev->new_chunk_sectors = n >> 9;
4258 		if (mddev->reshape_position == MaxSector)
4259 			mddev->chunk_sectors = n >> 9;
4260 	}
4261 	mddev_unlock(mddev);
4262 	return err ?: len;
4263 }
4264 static struct md_sysfs_entry md_chunk_size =
4265 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
4266 
4267 static ssize_t
resync_start_show(struct mddev * mddev,char * page)4268 resync_start_show(struct mddev *mddev, char *page)
4269 {
4270 	if (mddev->recovery_cp == MaxSector)
4271 		return sprintf(page, "none\n");
4272 	return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
4273 }
4274 
4275 static ssize_t
resync_start_store(struct mddev * mddev,const char * buf,size_t len)4276 resync_start_store(struct mddev *mddev, const char *buf, size_t len)
4277 {
4278 	unsigned long long n;
4279 	int err;
4280 
4281 	if (cmd_match(buf, "none"))
4282 		n = MaxSector;
4283 	else {
4284 		err = kstrtoull(buf, 10, &n);
4285 		if (err < 0)
4286 			return err;
4287 		if (n != (sector_t)n)
4288 			return -EINVAL;
4289 	}
4290 
4291 	err = mddev_lock(mddev);
4292 	if (err)
4293 		return err;
4294 	if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
4295 		err = -EBUSY;
4296 
4297 	if (!err) {
4298 		mddev->recovery_cp = n;
4299 		if (mddev->pers)
4300 			set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
4301 	}
4302 	mddev_unlock(mddev);
4303 	return err ?: len;
4304 }
4305 static struct md_sysfs_entry md_resync_start =
4306 __ATTR_PREALLOC(resync_start, S_IRUGO|S_IWUSR,
4307 		resync_start_show, resync_start_store);
4308 
4309 /*
4310  * The array state can be:
4311  *
4312  * clear
4313  *     No devices, no size, no level
4314  *     Equivalent to STOP_ARRAY ioctl
4315  * inactive
4316  *     May have some settings, but array is not active
4317  *        all IO results in error
4318  *     When written, doesn't tear down array, but just stops it
4319  * suspended (not supported yet)
4320  *     All IO requests will block. The array can be reconfigured.
4321  *     Writing this, if accepted, will block until array is quiescent
4322  * readonly
4323  *     no resync can happen.  no superblocks get written.
4324  *     write requests fail
4325  * read-auto
4326  *     like readonly, but behaves like 'clean' on a write request.
4327  *
4328  * clean - no pending writes, but otherwise active.
4329  *     When written to inactive array, starts without resync
4330  *     If a write request arrives then
4331  *       if metadata is known, mark 'dirty' and switch to 'active'.
4332  *       if not known, block and switch to write-pending
4333  *     If written to an active array that has pending writes, then fails.
4334  * active
4335  *     fully active: IO and resync can be happening.
4336  *     When written to inactive array, starts with resync
4337  *
4338  * write-pending
4339  *     clean, but writes are blocked waiting for 'active' to be written.
4340  *
4341  * active-idle
4342  *     like active, but no writes have been seen for a while (100msec).
4343  *
4344  * broken
4345 *     Array is failed. It's useful because mounted-arrays aren't stopped
4346 *     when array is failed, so this state will at least alert the user that
4347 *     something is wrong.
4348  */
4349 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
4350 		   write_pending, active_idle, broken, bad_word};
4351 static char *array_states[] = {
4352 	"clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
4353 	"write-pending", "active-idle", "broken", NULL };
4354 
match_word(const char * word,char ** list)4355 static int match_word(const char *word, char **list)
4356 {
4357 	int n;
4358 	for (n=0; list[n]; n++)
4359 		if (cmd_match(word, list[n]))
4360 			break;
4361 	return n;
4362 }
4363 
4364 static ssize_t
array_state_show(struct mddev * mddev,char * page)4365 array_state_show(struct mddev *mddev, char *page)
4366 {
4367 	enum array_state st = inactive;
4368 
4369 	if (mddev->pers && !test_bit(MD_NOT_READY, &mddev->flags)) {
4370 		switch(mddev->ro) {
4371 		case MD_RDONLY:
4372 			st = readonly;
4373 			break;
4374 		case MD_AUTO_READ:
4375 			st = read_auto;
4376 			break;
4377 		case MD_RDWR:
4378 			spin_lock(&mddev->lock);
4379 			if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
4380 				st = write_pending;
4381 			else if (mddev->in_sync)
4382 				st = clean;
4383 			else if (mddev->safemode)
4384 				st = active_idle;
4385 			else
4386 				st = active;
4387 			spin_unlock(&mddev->lock);
4388 		}
4389 
4390 		if (test_bit(MD_BROKEN, &mddev->flags) && st == clean)
4391 			st = broken;
4392 	} else {
4393 		if (list_empty(&mddev->disks) &&
4394 		    mddev->raid_disks == 0 &&
4395 		    mddev->dev_sectors == 0)
4396 			st = clear;
4397 		else
4398 			st = inactive;
4399 	}
4400 	return sprintf(page, "%s\n", array_states[st]);
4401 }
4402 
4403 static int do_md_stop(struct mddev *mddev, int ro);
4404 static int md_set_readonly(struct mddev *mddev);
4405 static int restart_array(struct mddev *mddev);
4406 
4407 static ssize_t
array_state_store(struct mddev * mddev,const char * buf,size_t len)4408 array_state_store(struct mddev *mddev, const char *buf, size_t len)
4409 {
4410 	int err = 0;
4411 	enum array_state st = match_word(buf, array_states);
4412 
4413 	/* No lock dependent actions */
4414 	switch (st) {
4415 	case suspended:		/* not supported yet */
4416 	case write_pending:	/* cannot be set */
4417 	case active_idle:	/* cannot be set */
4418 	case broken:		/* cannot be set */
4419 	case bad_word:
4420 		return -EINVAL;
4421 	case clear:
4422 	case readonly:
4423 	case inactive:
4424 	case read_auto:
4425 		if (!mddev->pers || !md_is_rdwr(mddev))
4426 			break;
4427 		/* write sysfs will not open mddev and opener should be 0 */
4428 		err = mddev_set_closing_and_sync_blockdev(mddev, 0);
4429 		if (err)
4430 			return err;
4431 		break;
4432 	default:
4433 		break;
4434 	}
4435 
4436 	if (mddev->pers && (st == active || st == clean) &&
4437 	    mddev->ro != MD_RDONLY) {
4438 		/* don't take reconfig_mutex when toggling between
4439 		 * clean and active
4440 		 */
4441 		spin_lock(&mddev->lock);
4442 		if (st == active) {
4443 			restart_array(mddev);
4444 			clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
4445 			md_wakeup_thread(mddev->thread);
4446 			wake_up(&mddev->sb_wait);
4447 		} else /* st == clean */ {
4448 			restart_array(mddev);
4449 			if (!set_in_sync(mddev))
4450 				err = -EBUSY;
4451 		}
4452 		if (!err)
4453 			sysfs_notify_dirent_safe(mddev->sysfs_state);
4454 		spin_unlock(&mddev->lock);
4455 		return err ?: len;
4456 	}
4457 	err = mddev_lock(mddev);
4458 	if (err)
4459 		return err;
4460 
4461 	switch (st) {
4462 	case inactive:
4463 		/* stop an active array, return 0 otherwise */
4464 		if (mddev->pers)
4465 			err = do_md_stop(mddev, 2);
4466 		break;
4467 	case clear:
4468 		err = do_md_stop(mddev, 0);
4469 		break;
4470 	case readonly:
4471 		if (mddev->pers)
4472 			err = md_set_readonly(mddev);
4473 		else {
4474 			mddev->ro = MD_RDONLY;
4475 			set_disk_ro(mddev->gendisk, 1);
4476 			err = do_md_run(mddev);
4477 		}
4478 		break;
4479 	case read_auto:
4480 		if (mddev->pers) {
4481 			if (md_is_rdwr(mddev))
4482 				err = md_set_readonly(mddev);
4483 			else if (mddev->ro == MD_RDONLY)
4484 				err = restart_array(mddev);
4485 			if (err == 0) {
4486 				mddev->ro = MD_AUTO_READ;
4487 				set_disk_ro(mddev->gendisk, 0);
4488 			}
4489 		} else {
4490 			mddev->ro = MD_AUTO_READ;
4491 			err = do_md_run(mddev);
4492 		}
4493 		break;
4494 	case clean:
4495 		if (mddev->pers) {
4496 			err = restart_array(mddev);
4497 			if (err)
4498 				break;
4499 			spin_lock(&mddev->lock);
4500 			if (!set_in_sync(mddev))
4501 				err = -EBUSY;
4502 			spin_unlock(&mddev->lock);
4503 		} else
4504 			err = -EINVAL;
4505 		break;
4506 	case active:
4507 		if (mddev->pers) {
4508 			err = restart_array(mddev);
4509 			if (err)
4510 				break;
4511 			clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
4512 			wake_up(&mddev->sb_wait);
4513 			err = 0;
4514 		} else {
4515 			mddev->ro = MD_RDWR;
4516 			set_disk_ro(mddev->gendisk, 0);
4517 			err = do_md_run(mddev);
4518 		}
4519 		break;
4520 	default:
4521 		err = -EINVAL;
4522 		break;
4523 	}
4524 
4525 	if (!err) {
4526 		if (mddev->hold_active == UNTIL_IOCTL)
4527 			mddev->hold_active = 0;
4528 		sysfs_notify_dirent_safe(mddev->sysfs_state);
4529 	}
4530 	mddev_unlock(mddev);
4531 
4532 	if (st == readonly || st == read_auto || st == inactive ||
4533 	    (err && st == clear))
4534 		clear_bit(MD_CLOSING, &mddev->flags);
4535 
4536 	return err ?: len;
4537 }
4538 static struct md_sysfs_entry md_array_state =
4539 __ATTR_PREALLOC(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
4540 
4541 static ssize_t
max_corrected_read_errors_show(struct mddev * mddev,char * page)4542 max_corrected_read_errors_show(struct mddev *mddev, char *page) {
4543 	return sprintf(page, "%d\n",
4544 		       atomic_read(&mddev->max_corr_read_errors));
4545 }
4546 
4547 static ssize_t
max_corrected_read_errors_store(struct mddev * mddev,const char * buf,size_t len)4548 max_corrected_read_errors_store(struct mddev *mddev, const char *buf, size_t len)
4549 {
4550 	unsigned int n;
4551 	int rv;
4552 
4553 	rv = kstrtouint(buf, 10, &n);
4554 	if (rv < 0)
4555 		return rv;
4556 	if (n > INT_MAX)
4557 		return -EINVAL;
4558 	atomic_set(&mddev->max_corr_read_errors, n);
4559 	return len;
4560 }
4561 
4562 static struct md_sysfs_entry max_corr_read_errors =
4563 __ATTR(max_read_errors, S_IRUGO|S_IWUSR, max_corrected_read_errors_show,
4564 	max_corrected_read_errors_store);
4565 
4566 static ssize_t
null_show(struct mddev * mddev,char * page)4567 null_show(struct mddev *mddev, char *page)
4568 {
4569 	return -EINVAL;
4570 }
4571 
4572 static ssize_t
new_dev_store(struct mddev * mddev,const char * buf,size_t len)4573 new_dev_store(struct mddev *mddev, const char *buf, size_t len)
4574 {
4575 	/* buf must be %d:%d\n? giving major and minor numbers */
4576 	/* The new device is added to the array.
4577 	 * If the array has a persistent superblock, we read the
4578 	 * superblock to initialise info and check validity.
4579 	 * Otherwise, only checking done is that in bind_rdev_to_array,
4580 	 * which mainly checks size.
4581 	 */
4582 	char *e;
4583 	int major = simple_strtoul(buf, &e, 10);
4584 	int minor;
4585 	dev_t dev;
4586 	struct md_rdev *rdev;
4587 	int err;
4588 
4589 	if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
4590 		return -EINVAL;
4591 	minor = simple_strtoul(e+1, &e, 10);
4592 	if (*e && *e != '\n')
4593 		return -EINVAL;
4594 	dev = MKDEV(major, minor);
4595 	if (major != MAJOR(dev) ||
4596 	    minor != MINOR(dev))
4597 		return -EOVERFLOW;
4598 
4599 	err = mddev_suspend_and_lock(mddev);
4600 	if (err)
4601 		return err;
4602 	if (mddev->persistent) {
4603 		rdev = md_import_device(dev, mddev->major_version,
4604 					mddev->minor_version);
4605 		if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
4606 			struct md_rdev *rdev0
4607 				= list_entry(mddev->disks.next,
4608 					     struct md_rdev, same_set);
4609 			err = super_types[mddev->major_version]
4610 				.load_super(rdev, rdev0, mddev->minor_version);
4611 			if (err < 0)
4612 				goto out;
4613 		}
4614 	} else if (mddev->external)
4615 		rdev = md_import_device(dev, -2, -1);
4616 	else
4617 		rdev = md_import_device(dev, -1, -1);
4618 
4619 	if (IS_ERR(rdev)) {
4620 		mddev_unlock_and_resume(mddev);
4621 		return PTR_ERR(rdev);
4622 	}
4623 	err = bind_rdev_to_array(rdev, mddev);
4624  out:
4625 	if (err)
4626 		export_rdev(rdev, mddev);
4627 	mddev_unlock_and_resume(mddev);
4628 	if (!err)
4629 		md_new_event();
4630 	return err ? err : len;
4631 }
4632 
4633 static struct md_sysfs_entry md_new_device =
4634 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
4635 
4636 static ssize_t
bitmap_store(struct mddev * mddev,const char * buf,size_t len)4637 bitmap_store(struct mddev *mddev, const char *buf, size_t len)
4638 {
4639 	char *end;
4640 	unsigned long chunk, end_chunk;
4641 	int err;
4642 
4643 	err = mddev_lock(mddev);
4644 	if (err)
4645 		return err;
4646 	if (!mddev->bitmap)
4647 		goto out;
4648 	/* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
4649 	while (*buf) {
4650 		chunk = end_chunk = simple_strtoul(buf, &end, 0);
4651 		if (buf == end)
4652 			break;
4653 
4654 		if (*end == '-') { /* range */
4655 			buf = end + 1;
4656 			end_chunk = simple_strtoul(buf, &end, 0);
4657 			if (buf == end)
4658 				break;
4659 		}
4660 
4661 		if (*end && !isspace(*end))
4662 			break;
4663 
4664 		mddev->bitmap_ops->dirty_bits(mddev, chunk, end_chunk);
4665 		buf = skip_spaces(end);
4666 	}
4667 	mddev->bitmap_ops->unplug(mddev, true); /* flush the bits to disk */
4668 out:
4669 	mddev_unlock(mddev);
4670 	return len;
4671 }
4672 
4673 static struct md_sysfs_entry md_bitmap =
4674 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
4675 
4676 static ssize_t
size_show(struct mddev * mddev,char * page)4677 size_show(struct mddev *mddev, char *page)
4678 {
4679 	return sprintf(page, "%llu\n",
4680 		(unsigned long long)mddev->dev_sectors / 2);
4681 }
4682 
4683 static int update_size(struct mddev *mddev, sector_t num_sectors);
4684 
4685 static ssize_t
size_store(struct mddev * mddev,const char * buf,size_t len)4686 size_store(struct mddev *mddev, const char *buf, size_t len)
4687 {
4688 	/* If array is inactive, we can reduce the component size, but
4689 	 * not increase it (except from 0).
4690 	 * If array is active, we can try an on-line resize
4691 	 */
4692 	sector_t sectors;
4693 	int err = strict_blocks_to_sectors(buf, &sectors);
4694 
4695 	if (err < 0)
4696 		return err;
4697 	err = mddev_lock(mddev);
4698 	if (err)
4699 		return err;
4700 	if (mddev->pers) {
4701 		err = update_size(mddev, sectors);
4702 		if (err == 0)
4703 			md_update_sb(mddev, 1);
4704 	} else {
4705 		if (mddev->dev_sectors == 0 ||
4706 		    mddev->dev_sectors > sectors)
4707 			mddev->dev_sectors = sectors;
4708 		else
4709 			err = -ENOSPC;
4710 	}
4711 	mddev_unlock(mddev);
4712 	return err ? err : len;
4713 }
4714 
4715 static struct md_sysfs_entry md_size =
4716 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
4717 
4718 /* Metadata version.
4719  * This is one of
4720  *   'none' for arrays with no metadata (good luck...)
4721  *   'external' for arrays with externally managed metadata,
4722  * or N.M for internally known formats
4723  */
4724 static ssize_t
metadata_show(struct mddev * mddev,char * page)4725 metadata_show(struct mddev *mddev, char *page)
4726 {
4727 	if (mddev->persistent)
4728 		return sprintf(page, "%d.%d\n",
4729 			       mddev->major_version, mddev->minor_version);
4730 	else if (mddev->external)
4731 		return sprintf(page, "external:%s\n", mddev->metadata_type);
4732 	else
4733 		return sprintf(page, "none\n");
4734 }
4735 
4736 static ssize_t
metadata_store(struct mddev * mddev,const char * buf,size_t len)4737 metadata_store(struct mddev *mddev, const char *buf, size_t len)
4738 {
4739 	int major, minor;
4740 	char *e;
4741 	int err;
4742 	/* Changing the details of 'external' metadata is
4743 	 * always permitted.  Otherwise there must be
4744 	 * no devices attached to the array.
4745 	 */
4746 
4747 	err = mddev_lock(mddev);
4748 	if (err)
4749 		return err;
4750 	err = -EBUSY;
4751 	if (mddev->external && strncmp(buf, "external:", 9) == 0)
4752 		;
4753 	else if (!list_empty(&mddev->disks))
4754 		goto out_unlock;
4755 
4756 	err = 0;
4757 	if (cmd_match(buf, "none")) {
4758 		mddev->persistent = 0;
4759 		mddev->external = 0;
4760 		mddev->major_version = 0;
4761 		mddev->minor_version = 90;
4762 		goto out_unlock;
4763 	}
4764 	if (strncmp(buf, "external:", 9) == 0) {
4765 		size_t namelen = len-9;
4766 		if (namelen >= sizeof(mddev->metadata_type))
4767 			namelen = sizeof(mddev->metadata_type)-1;
4768 		memcpy(mddev->metadata_type, buf+9, namelen);
4769 		mddev->metadata_type[namelen] = 0;
4770 		if (namelen && mddev->metadata_type[namelen-1] == '\n')
4771 			mddev->metadata_type[--namelen] = 0;
4772 		mddev->persistent = 0;
4773 		mddev->external = 1;
4774 		mddev->major_version = 0;
4775 		mddev->minor_version = 90;
4776 		goto out_unlock;
4777 	}
4778 	major = simple_strtoul(buf, &e, 10);
4779 	err = -EINVAL;
4780 	if (e==buf || *e != '.')
4781 		goto out_unlock;
4782 	buf = e+1;
4783 	minor = simple_strtoul(buf, &e, 10);
4784 	if (e==buf || (*e && *e != '\n') )
4785 		goto out_unlock;
4786 	err = -ENOENT;
4787 	if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
4788 		goto out_unlock;
4789 	mddev->major_version = major;
4790 	mddev->minor_version = minor;
4791 	mddev->persistent = 1;
4792 	mddev->external = 0;
4793 	err = 0;
4794 out_unlock:
4795 	mddev_unlock(mddev);
4796 	return err ?: len;
4797 }
4798 
4799 static struct md_sysfs_entry md_metadata =
4800 __ATTR_PREALLOC(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
4801 
md_sync_action(struct mddev * mddev)4802 enum sync_action md_sync_action(struct mddev *mddev)
4803 {
4804 	unsigned long recovery = mddev->recovery;
4805 
4806 	/*
4807 	 * frozen has the highest priority, means running sync_thread will be
4808 	 * stopped immediately, and no new sync_thread can start.
4809 	 */
4810 	if (test_bit(MD_RECOVERY_FROZEN, &recovery))
4811 		return ACTION_FROZEN;
4812 
4813 	/*
4814 	 * read-only array can't register sync_thread, and it can only
4815 	 * add/remove spares.
4816 	 */
4817 	if (!md_is_rdwr(mddev))
4818 		return ACTION_IDLE;
4819 
4820 	/*
4821 	 * idle means no sync_thread is running, and no new sync_thread is
4822 	 * requested.
4823 	 */
4824 	if (!test_bit(MD_RECOVERY_RUNNING, &recovery) &&
4825 	    !test_bit(MD_RECOVERY_NEEDED, &recovery))
4826 		return ACTION_IDLE;
4827 
4828 	if (test_bit(MD_RECOVERY_RESHAPE, &recovery) ||
4829 	    mddev->reshape_position != MaxSector)
4830 		return ACTION_RESHAPE;
4831 
4832 	if (test_bit(MD_RECOVERY_RECOVER, &recovery))
4833 		return ACTION_RECOVER;
4834 
4835 	if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
4836 		/*
4837 		 * MD_RECOVERY_CHECK must be paired with
4838 		 * MD_RECOVERY_REQUESTED.
4839 		 */
4840 		if (test_bit(MD_RECOVERY_CHECK, &recovery))
4841 			return ACTION_CHECK;
4842 		if (test_bit(MD_RECOVERY_REQUESTED, &recovery))
4843 			return ACTION_REPAIR;
4844 		return ACTION_RESYNC;
4845 	}
4846 
4847 	/*
4848 	 * MD_RECOVERY_NEEDED or MD_RECOVERY_RUNNING is set, however, no
4849 	 * sync_action is specified.
4850 	 */
4851 	return ACTION_IDLE;
4852 }
4853 
md_sync_action_by_name(const char * page)4854 enum sync_action md_sync_action_by_name(const char *page)
4855 {
4856 	enum sync_action action;
4857 
4858 	for (action = 0; action < NR_SYNC_ACTIONS; ++action) {
4859 		if (cmd_match(page, action_name[action]))
4860 			return action;
4861 	}
4862 
4863 	return NR_SYNC_ACTIONS;
4864 }
4865 
md_sync_action_name(enum sync_action action)4866 const char *md_sync_action_name(enum sync_action action)
4867 {
4868 	return action_name[action];
4869 }
4870 
4871 static ssize_t
action_show(struct mddev * mddev,char * page)4872 action_show(struct mddev *mddev, char *page)
4873 {
4874 	enum sync_action action = md_sync_action(mddev);
4875 
4876 	return sprintf(page, "%s\n", md_sync_action_name(action));
4877 }
4878 
4879 /**
4880  * stop_sync_thread() - wait for sync_thread to stop if it's running.
4881  * @mddev:	the array.
4882  * @locked:	if set, reconfig_mutex will still be held after this function
4883  *		return; if not set, reconfig_mutex will be released after this
4884  *		function return.
4885  */
stop_sync_thread(struct mddev * mddev,bool locked)4886 static void stop_sync_thread(struct mddev *mddev, bool locked)
4887 {
4888 	int sync_seq = atomic_read(&mddev->sync_seq);
4889 
4890 	if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
4891 		if (!locked)
4892 			mddev_unlock(mddev);
4893 		return;
4894 	}
4895 
4896 	mddev_unlock(mddev);
4897 
4898 	set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4899 	/*
4900 	 * Thread might be blocked waiting for metadata update which will now
4901 	 * never happen
4902 	 */
4903 	md_wakeup_thread_directly(mddev->sync_thread);
4904 	if (work_pending(&mddev->sync_work))
4905 		flush_work(&mddev->sync_work);
4906 
4907 	wait_event(resync_wait,
4908 		   !test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4909 		   (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery) &&
4910 		    sync_seq != atomic_read(&mddev->sync_seq)));
4911 
4912 	if (locked)
4913 		mddev_lock_nointr(mddev);
4914 }
4915 
md_idle_sync_thread(struct mddev * mddev)4916 void md_idle_sync_thread(struct mddev *mddev)
4917 {
4918 	lockdep_assert_held(&mddev->reconfig_mutex);
4919 
4920 	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4921 	stop_sync_thread(mddev, true);
4922 }
4923 EXPORT_SYMBOL_GPL(md_idle_sync_thread);
4924 
md_frozen_sync_thread(struct mddev * mddev)4925 void md_frozen_sync_thread(struct mddev *mddev)
4926 {
4927 	lockdep_assert_held(&mddev->reconfig_mutex);
4928 
4929 	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4930 	stop_sync_thread(mddev, true);
4931 }
4932 EXPORT_SYMBOL_GPL(md_frozen_sync_thread);
4933 
md_unfrozen_sync_thread(struct mddev * mddev)4934 void md_unfrozen_sync_thread(struct mddev *mddev)
4935 {
4936 	lockdep_assert_held(&mddev->reconfig_mutex);
4937 
4938 	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4939 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4940 	md_wakeup_thread(mddev->thread);
4941 	sysfs_notify_dirent_safe(mddev->sysfs_action);
4942 }
4943 EXPORT_SYMBOL_GPL(md_unfrozen_sync_thread);
4944 
mddev_start_reshape(struct mddev * mddev)4945 static int mddev_start_reshape(struct mddev *mddev)
4946 {
4947 	int ret;
4948 
4949 	if (mddev->pers->start_reshape == NULL)
4950 		return -EINVAL;
4951 
4952 	if (mddev->reshape_position == MaxSector ||
4953 	    mddev->pers->check_reshape == NULL ||
4954 	    mddev->pers->check_reshape(mddev)) {
4955 		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4956 		ret = mddev->pers->start_reshape(mddev);
4957 		if (ret)
4958 			return ret;
4959 	} else {
4960 		/*
4961 		 * If reshape is still in progress, and md_check_recovery() can
4962 		 * continue to reshape, don't restart reshape because data can
4963 		 * be corrupted for raid456.
4964 		 */
4965 		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4966 	}
4967 
4968 	sysfs_notify_dirent_safe(mddev->sysfs_degraded);
4969 	return 0;
4970 }
4971 
4972 static ssize_t
action_store(struct mddev * mddev,const char * page,size_t len)4973 action_store(struct mddev *mddev, const char *page, size_t len)
4974 {
4975 	int ret;
4976 	enum sync_action action;
4977 
4978 	if (!mddev->pers || !mddev->pers->sync_request)
4979 		return -EINVAL;
4980 
4981 retry:
4982 	if (work_busy(&mddev->sync_work))
4983 		flush_work(&mddev->sync_work);
4984 
4985 	ret = mddev_lock(mddev);
4986 	if (ret)
4987 		return ret;
4988 
4989 	if (work_busy(&mddev->sync_work)) {
4990 		mddev_unlock(mddev);
4991 		goto retry;
4992 	}
4993 
4994 	action = md_sync_action_by_name(page);
4995 
4996 	/* TODO: mdadm rely on "idle" to start sync_thread. */
4997 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
4998 		switch (action) {
4999 		case ACTION_FROZEN:
5000 			md_frozen_sync_thread(mddev);
5001 			ret = len;
5002 			goto out;
5003 		case ACTION_IDLE:
5004 			md_idle_sync_thread(mddev);
5005 			break;
5006 		case ACTION_RESHAPE:
5007 		case ACTION_RECOVER:
5008 		case ACTION_CHECK:
5009 		case ACTION_REPAIR:
5010 		case ACTION_RESYNC:
5011 			ret = -EBUSY;
5012 			goto out;
5013 		default:
5014 			ret = -EINVAL;
5015 			goto out;
5016 		}
5017 	} else {
5018 		switch (action) {
5019 		case ACTION_FROZEN:
5020 			set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5021 			ret = len;
5022 			goto out;
5023 		case ACTION_RESHAPE:
5024 			clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5025 			ret = mddev_start_reshape(mddev);
5026 			if (ret)
5027 				goto out;
5028 			break;
5029 		case ACTION_RECOVER:
5030 			clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5031 			set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
5032 			break;
5033 		case ACTION_CHECK:
5034 			set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
5035 			fallthrough;
5036 		case ACTION_REPAIR:
5037 			set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
5038 			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
5039 			fallthrough;
5040 		case ACTION_RESYNC:
5041 		case ACTION_IDLE:
5042 			clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5043 			break;
5044 		default:
5045 			ret = -EINVAL;
5046 			goto out;
5047 		}
5048 	}
5049 
5050 	if (mddev->ro == MD_AUTO_READ) {
5051 		/* A write to sync_action is enough to justify
5052 		 * canceling read-auto mode
5053 		 */
5054 		mddev->ro = MD_RDWR;
5055 		md_wakeup_thread(mddev->sync_thread);
5056 	}
5057 
5058 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5059 	md_wakeup_thread(mddev->thread);
5060 	sysfs_notify_dirent_safe(mddev->sysfs_action);
5061 	ret = len;
5062 
5063 out:
5064 	mddev_unlock(mddev);
5065 	return ret;
5066 }
5067 
5068 static struct md_sysfs_entry md_scan_mode =
5069 __ATTR_PREALLOC(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
5070 
5071 static ssize_t
last_sync_action_show(struct mddev * mddev,char * page)5072 last_sync_action_show(struct mddev *mddev, char *page)
5073 {
5074 	return sprintf(page, "%s\n",
5075 		       md_sync_action_name(mddev->last_sync_action));
5076 }
5077 
5078 static struct md_sysfs_entry md_last_scan_mode = __ATTR_RO(last_sync_action);
5079 
5080 static ssize_t
mismatch_cnt_show(struct mddev * mddev,char * page)5081 mismatch_cnt_show(struct mddev *mddev, char *page)
5082 {
5083 	return sprintf(page, "%llu\n",
5084 		       (unsigned long long)
5085 		       atomic64_read(&mddev->resync_mismatches));
5086 }
5087 
5088 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
5089 
5090 static ssize_t
sync_min_show(struct mddev * mddev,char * page)5091 sync_min_show(struct mddev *mddev, char *page)
5092 {
5093 	return sprintf(page, "%d (%s)\n", speed_min(mddev),
5094 		       mddev->sync_speed_min ? "local": "system");
5095 }
5096 
5097 static ssize_t
sync_min_store(struct mddev * mddev,const char * buf,size_t len)5098 sync_min_store(struct mddev *mddev, const char *buf, size_t len)
5099 {
5100 	unsigned int min;
5101 	int rv;
5102 
5103 	if (strncmp(buf, "system", 6)==0) {
5104 		min = 0;
5105 	} else {
5106 		rv = kstrtouint(buf, 10, &min);
5107 		if (rv < 0)
5108 			return rv;
5109 		if (min == 0)
5110 			return -EINVAL;
5111 	}
5112 	mddev->sync_speed_min = min;
5113 	return len;
5114 }
5115 
5116 static struct md_sysfs_entry md_sync_min =
5117 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
5118 
5119 static ssize_t
sync_max_show(struct mddev * mddev,char * page)5120 sync_max_show(struct mddev *mddev, char *page)
5121 {
5122 	return sprintf(page, "%d (%s)\n", speed_max(mddev),
5123 		       mddev->sync_speed_max ? "local": "system");
5124 }
5125 
5126 static ssize_t
sync_max_store(struct mddev * mddev,const char * buf,size_t len)5127 sync_max_store(struct mddev *mddev, const char *buf, size_t len)
5128 {
5129 	unsigned int max;
5130 	int rv;
5131 
5132 	if (strncmp(buf, "system", 6)==0) {
5133 		max = 0;
5134 	} else {
5135 		rv = kstrtouint(buf, 10, &max);
5136 		if (rv < 0)
5137 			return rv;
5138 		if (max == 0)
5139 			return -EINVAL;
5140 	}
5141 	mddev->sync_speed_max = max;
5142 	return len;
5143 }
5144 
5145 static struct md_sysfs_entry md_sync_max =
5146 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
5147 
5148 static ssize_t
degraded_show(struct mddev * mddev,char * page)5149 degraded_show(struct mddev *mddev, char *page)
5150 {
5151 	return sprintf(page, "%d\n", mddev->degraded);
5152 }
5153 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
5154 
5155 static ssize_t
sync_force_parallel_show(struct mddev * mddev,char * page)5156 sync_force_parallel_show(struct mddev *mddev, char *page)
5157 {
5158 	return sprintf(page, "%d\n", mddev->parallel_resync);
5159 }
5160 
5161 static ssize_t
sync_force_parallel_store(struct mddev * mddev,const char * buf,size_t len)5162 sync_force_parallel_store(struct mddev *mddev, const char *buf, size_t len)
5163 {
5164 	long n;
5165 
5166 	if (kstrtol(buf, 10, &n))
5167 		return -EINVAL;
5168 
5169 	if (n != 0 && n != 1)
5170 		return -EINVAL;
5171 
5172 	mddev->parallel_resync = n;
5173 
5174 	if (mddev->sync_thread)
5175 		wake_up(&resync_wait);
5176 
5177 	return len;
5178 }
5179 
5180 /* force parallel resync, even with shared block devices */
5181 static struct md_sysfs_entry md_sync_force_parallel =
5182 __ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
5183        sync_force_parallel_show, sync_force_parallel_store);
5184 
5185 static ssize_t
sync_speed_show(struct mddev * mddev,char * page)5186 sync_speed_show(struct mddev *mddev, char *page)
5187 {
5188 	unsigned long resync, dt, db;
5189 	if (mddev->curr_resync == MD_RESYNC_NONE)
5190 		return sprintf(page, "none\n");
5191 	resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
5192 	dt = (jiffies - mddev->resync_mark) / HZ;
5193 	if (!dt) dt++;
5194 	db = resync - mddev->resync_mark_cnt;
5195 	return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
5196 }
5197 
5198 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
5199 
5200 static ssize_t
sync_completed_show(struct mddev * mddev,char * page)5201 sync_completed_show(struct mddev *mddev, char *page)
5202 {
5203 	unsigned long long max_sectors, resync;
5204 
5205 	if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
5206 		return sprintf(page, "none\n");
5207 
5208 	if (mddev->curr_resync == MD_RESYNC_YIELDED ||
5209 	    mddev->curr_resync == MD_RESYNC_DELAYED)
5210 		return sprintf(page, "delayed\n");
5211 
5212 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
5213 	    test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
5214 		max_sectors = mddev->resync_max_sectors;
5215 	else
5216 		max_sectors = mddev->dev_sectors;
5217 
5218 	resync = mddev->curr_resync_completed;
5219 	return sprintf(page, "%llu / %llu\n", resync, max_sectors);
5220 }
5221 
5222 static struct md_sysfs_entry md_sync_completed =
5223 	__ATTR_PREALLOC(sync_completed, S_IRUGO, sync_completed_show, NULL);
5224 
5225 static ssize_t
min_sync_show(struct mddev * mddev,char * page)5226 min_sync_show(struct mddev *mddev, char *page)
5227 {
5228 	return sprintf(page, "%llu\n",
5229 		       (unsigned long long)mddev->resync_min);
5230 }
5231 static ssize_t
min_sync_store(struct mddev * mddev,const char * buf,size_t len)5232 min_sync_store(struct mddev *mddev, const char *buf, size_t len)
5233 {
5234 	unsigned long long min;
5235 	int err;
5236 
5237 	if (kstrtoull(buf, 10, &min))
5238 		return -EINVAL;
5239 
5240 	spin_lock(&mddev->lock);
5241 	err = -EINVAL;
5242 	if (min > mddev->resync_max)
5243 		goto out_unlock;
5244 
5245 	err = -EBUSY;
5246 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
5247 		goto out_unlock;
5248 
5249 	/* Round down to multiple of 4K for safety */
5250 	mddev->resync_min = round_down(min, 8);
5251 	err = 0;
5252 
5253 out_unlock:
5254 	spin_unlock(&mddev->lock);
5255 	return err ?: len;
5256 }
5257 
5258 static struct md_sysfs_entry md_min_sync =
5259 __ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
5260 
5261 static ssize_t
max_sync_show(struct mddev * mddev,char * page)5262 max_sync_show(struct mddev *mddev, char *page)
5263 {
5264 	if (mddev->resync_max == MaxSector)
5265 		return sprintf(page, "max\n");
5266 	else
5267 		return sprintf(page, "%llu\n",
5268 			       (unsigned long long)mddev->resync_max);
5269 }
5270 static ssize_t
max_sync_store(struct mddev * mddev,const char * buf,size_t len)5271 max_sync_store(struct mddev *mddev, const char *buf, size_t len)
5272 {
5273 	int err;
5274 	spin_lock(&mddev->lock);
5275 	if (strncmp(buf, "max", 3) == 0)
5276 		mddev->resync_max = MaxSector;
5277 	else {
5278 		unsigned long long max;
5279 		int chunk;
5280 
5281 		err = -EINVAL;
5282 		if (kstrtoull(buf, 10, &max))
5283 			goto out_unlock;
5284 		if (max < mddev->resync_min)
5285 			goto out_unlock;
5286 
5287 		err = -EBUSY;
5288 		if (max < mddev->resync_max && md_is_rdwr(mddev) &&
5289 		    test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
5290 			goto out_unlock;
5291 
5292 		/* Must be a multiple of chunk_size */
5293 		chunk = mddev->chunk_sectors;
5294 		if (chunk) {
5295 			sector_t temp = max;
5296 
5297 			err = -EINVAL;
5298 			if (sector_div(temp, chunk))
5299 				goto out_unlock;
5300 		}
5301 		mddev->resync_max = max;
5302 	}
5303 	wake_up(&mddev->recovery_wait);
5304 	err = 0;
5305 out_unlock:
5306 	spin_unlock(&mddev->lock);
5307 	return err ?: len;
5308 }
5309 
5310 static struct md_sysfs_entry md_max_sync =
5311 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
5312 
5313 static ssize_t
suspend_lo_show(struct mddev * mddev,char * page)5314 suspend_lo_show(struct mddev *mddev, char *page)
5315 {
5316 	return sprintf(page, "%llu\n",
5317 		       (unsigned long long)READ_ONCE(mddev->suspend_lo));
5318 }
5319 
5320 static ssize_t
suspend_lo_store(struct mddev * mddev,const char * buf,size_t len)5321 suspend_lo_store(struct mddev *mddev, const char *buf, size_t len)
5322 {
5323 	unsigned long long new;
5324 	int err;
5325 
5326 	err = kstrtoull(buf, 10, &new);
5327 	if (err < 0)
5328 		return err;
5329 	if (new != (sector_t)new)
5330 		return -EINVAL;
5331 
5332 	err = mddev_suspend(mddev, true);
5333 	if (err)
5334 		return err;
5335 
5336 	WRITE_ONCE(mddev->suspend_lo, new);
5337 	mddev_resume(mddev);
5338 
5339 	return len;
5340 }
5341 static struct md_sysfs_entry md_suspend_lo =
5342 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
5343 
5344 static ssize_t
suspend_hi_show(struct mddev * mddev,char * page)5345 suspend_hi_show(struct mddev *mddev, char *page)
5346 {
5347 	return sprintf(page, "%llu\n",
5348 		       (unsigned long long)READ_ONCE(mddev->suspend_hi));
5349 }
5350 
5351 static ssize_t
suspend_hi_store(struct mddev * mddev,const char * buf,size_t len)5352 suspend_hi_store(struct mddev *mddev, const char *buf, size_t len)
5353 {
5354 	unsigned long long new;
5355 	int err;
5356 
5357 	err = kstrtoull(buf, 10, &new);
5358 	if (err < 0)
5359 		return err;
5360 	if (new != (sector_t)new)
5361 		return -EINVAL;
5362 
5363 	err = mddev_suspend(mddev, true);
5364 	if (err)
5365 		return err;
5366 
5367 	WRITE_ONCE(mddev->suspend_hi, new);
5368 	mddev_resume(mddev);
5369 
5370 	return len;
5371 }
5372 static struct md_sysfs_entry md_suspend_hi =
5373 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
5374 
5375 static ssize_t
reshape_position_show(struct mddev * mddev,char * page)5376 reshape_position_show(struct mddev *mddev, char *page)
5377 {
5378 	if (mddev->reshape_position != MaxSector)
5379 		return sprintf(page, "%llu\n",
5380 			       (unsigned long long)mddev->reshape_position);
5381 	strcpy(page, "none\n");
5382 	return 5;
5383 }
5384 
5385 static ssize_t
reshape_position_store(struct mddev * mddev,const char * buf,size_t len)5386 reshape_position_store(struct mddev *mddev, const char *buf, size_t len)
5387 {
5388 	struct md_rdev *rdev;
5389 	unsigned long long new;
5390 	int err;
5391 
5392 	err = kstrtoull(buf, 10, &new);
5393 	if (err < 0)
5394 		return err;
5395 	if (new != (sector_t)new)
5396 		return -EINVAL;
5397 	err = mddev_lock(mddev);
5398 	if (err)
5399 		return err;
5400 	err = -EBUSY;
5401 	if (mddev->pers)
5402 		goto unlock;
5403 	mddev->reshape_position = new;
5404 	mddev->delta_disks = 0;
5405 	mddev->reshape_backwards = 0;
5406 	mddev->new_level = mddev->level;
5407 	mddev->new_layout = mddev->layout;
5408 	mddev->new_chunk_sectors = mddev->chunk_sectors;
5409 	rdev_for_each(rdev, mddev)
5410 		rdev->new_data_offset = rdev->data_offset;
5411 	err = 0;
5412 unlock:
5413 	mddev_unlock(mddev);
5414 	return err ?: len;
5415 }
5416 
5417 static struct md_sysfs_entry md_reshape_position =
5418 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
5419        reshape_position_store);
5420 
5421 static ssize_t
reshape_direction_show(struct mddev * mddev,char * page)5422 reshape_direction_show(struct mddev *mddev, char *page)
5423 {
5424 	return sprintf(page, "%s\n",
5425 		       mddev->reshape_backwards ? "backwards" : "forwards");
5426 }
5427 
5428 static ssize_t
reshape_direction_store(struct mddev * mddev,const char * buf,size_t len)5429 reshape_direction_store(struct mddev *mddev, const char *buf, size_t len)
5430 {
5431 	int backwards = 0;
5432 	int err;
5433 
5434 	if (cmd_match(buf, "forwards"))
5435 		backwards = 0;
5436 	else if (cmd_match(buf, "backwards"))
5437 		backwards = 1;
5438 	else
5439 		return -EINVAL;
5440 	if (mddev->reshape_backwards == backwards)
5441 		return len;
5442 
5443 	err = mddev_lock(mddev);
5444 	if (err)
5445 		return err;
5446 	/* check if we are allowed to change */
5447 	if (mddev->delta_disks)
5448 		err = -EBUSY;
5449 	else if (mddev->persistent &&
5450 	    mddev->major_version == 0)
5451 		err =  -EINVAL;
5452 	else
5453 		mddev->reshape_backwards = backwards;
5454 	mddev_unlock(mddev);
5455 	return err ?: len;
5456 }
5457 
5458 static struct md_sysfs_entry md_reshape_direction =
5459 __ATTR(reshape_direction, S_IRUGO|S_IWUSR, reshape_direction_show,
5460        reshape_direction_store);
5461 
5462 static ssize_t
array_size_show(struct mddev * mddev,char * page)5463 array_size_show(struct mddev *mddev, char *page)
5464 {
5465 	if (mddev->external_size)
5466 		return sprintf(page, "%llu\n",
5467 			       (unsigned long long)mddev->array_sectors/2);
5468 	else
5469 		return sprintf(page, "default\n");
5470 }
5471 
5472 static ssize_t
array_size_store(struct mddev * mddev,const char * buf,size_t len)5473 array_size_store(struct mddev *mddev, const char *buf, size_t len)
5474 {
5475 	sector_t sectors;
5476 	int err;
5477 
5478 	err = mddev_lock(mddev);
5479 	if (err)
5480 		return err;
5481 
5482 	/* cluster raid doesn't support change array_sectors */
5483 	if (mddev_is_clustered(mddev)) {
5484 		mddev_unlock(mddev);
5485 		return -EINVAL;
5486 	}
5487 
5488 	if (strncmp(buf, "default", 7) == 0) {
5489 		if (mddev->pers)
5490 			sectors = mddev->pers->size(mddev, 0, 0);
5491 		else
5492 			sectors = mddev->array_sectors;
5493 
5494 		mddev->external_size = 0;
5495 	} else {
5496 		if (strict_blocks_to_sectors(buf, &sectors) < 0)
5497 			err = -EINVAL;
5498 		else if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
5499 			err = -E2BIG;
5500 		else
5501 			mddev->external_size = 1;
5502 	}
5503 
5504 	if (!err) {
5505 		mddev->array_sectors = sectors;
5506 		if (mddev->pers)
5507 			set_capacity_and_notify(mddev->gendisk,
5508 						mddev->array_sectors);
5509 	}
5510 	mddev_unlock(mddev);
5511 	return err ?: len;
5512 }
5513 
5514 static struct md_sysfs_entry md_array_size =
5515 __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
5516        array_size_store);
5517 
5518 static ssize_t
consistency_policy_show(struct mddev * mddev,char * page)5519 consistency_policy_show(struct mddev *mddev, char *page)
5520 {
5521 	int ret;
5522 
5523 	if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) {
5524 		ret = sprintf(page, "journal\n");
5525 	} else if (test_bit(MD_HAS_PPL, &mddev->flags)) {
5526 		ret = sprintf(page, "ppl\n");
5527 	} else if (mddev->bitmap) {
5528 		ret = sprintf(page, "bitmap\n");
5529 	} else if (mddev->pers) {
5530 		if (mddev->pers->sync_request)
5531 			ret = sprintf(page, "resync\n");
5532 		else
5533 			ret = sprintf(page, "none\n");
5534 	} else {
5535 		ret = sprintf(page, "unknown\n");
5536 	}
5537 
5538 	return ret;
5539 }
5540 
5541 static ssize_t
consistency_policy_store(struct mddev * mddev,const char * buf,size_t len)5542 consistency_policy_store(struct mddev *mddev, const char *buf, size_t len)
5543 {
5544 	int err = 0;
5545 
5546 	if (mddev->pers) {
5547 		if (mddev->pers->change_consistency_policy)
5548 			err = mddev->pers->change_consistency_policy(mddev, buf);
5549 		else
5550 			err = -EBUSY;
5551 	} else if (mddev->external && strncmp(buf, "ppl", 3) == 0) {
5552 		set_bit(MD_HAS_PPL, &mddev->flags);
5553 	} else {
5554 		err = -EINVAL;
5555 	}
5556 
5557 	return err ? err : len;
5558 }
5559 
5560 static struct md_sysfs_entry md_consistency_policy =
5561 __ATTR(consistency_policy, S_IRUGO | S_IWUSR, consistency_policy_show,
5562        consistency_policy_store);
5563 
fail_last_dev_show(struct mddev * mddev,char * page)5564 static ssize_t fail_last_dev_show(struct mddev *mddev, char *page)
5565 {
5566 	return sprintf(page, "%d\n", mddev->fail_last_dev);
5567 }
5568 
5569 /*
5570  * Setting fail_last_dev to true to allow last device to be forcibly removed
5571  * from RAID1/RAID10.
5572  */
5573 static ssize_t
fail_last_dev_store(struct mddev * mddev,const char * buf,size_t len)5574 fail_last_dev_store(struct mddev *mddev, const char *buf, size_t len)
5575 {
5576 	int ret;
5577 	bool value;
5578 
5579 	ret = kstrtobool(buf, &value);
5580 	if (ret)
5581 		return ret;
5582 
5583 	if (value != mddev->fail_last_dev)
5584 		mddev->fail_last_dev = value;
5585 
5586 	return len;
5587 }
5588 static struct md_sysfs_entry md_fail_last_dev =
5589 __ATTR(fail_last_dev, S_IRUGO | S_IWUSR, fail_last_dev_show,
5590        fail_last_dev_store);
5591 
serialize_policy_show(struct mddev * mddev,char * page)5592 static ssize_t serialize_policy_show(struct mddev *mddev, char *page)
5593 {
5594 	if (mddev->pers == NULL || (mddev->pers->head.id != ID_RAID1))
5595 		return sprintf(page, "n/a\n");
5596 	else
5597 		return sprintf(page, "%d\n", mddev->serialize_policy);
5598 }
5599 
5600 /*
5601  * Setting serialize_policy to true to enforce write IO is not reordered
5602  * for raid1.
5603  */
5604 static ssize_t
serialize_policy_store(struct mddev * mddev,const char * buf,size_t len)5605 serialize_policy_store(struct mddev *mddev, const char *buf, size_t len)
5606 {
5607 	int err;
5608 	bool value;
5609 
5610 	err = kstrtobool(buf, &value);
5611 	if (err)
5612 		return err;
5613 
5614 	if (value == mddev->serialize_policy)
5615 		return len;
5616 
5617 	err = mddev_suspend_and_lock(mddev);
5618 	if (err)
5619 		return err;
5620 	if (mddev->pers == NULL || (mddev->pers->head.id != ID_RAID1)) {
5621 		pr_err("md: serialize_policy is only effective for raid1\n");
5622 		err = -EINVAL;
5623 		goto unlock;
5624 	}
5625 
5626 	if (value)
5627 		mddev_create_serial_pool(mddev, NULL);
5628 	else
5629 		mddev_destroy_serial_pool(mddev, NULL);
5630 	mddev->serialize_policy = value;
5631 unlock:
5632 	mddev_unlock_and_resume(mddev);
5633 	return err ?: len;
5634 }
5635 
5636 static struct md_sysfs_entry md_serialize_policy =
5637 __ATTR(serialize_policy, S_IRUGO | S_IWUSR, serialize_policy_show,
5638        serialize_policy_store);
5639 
5640 
5641 static struct attribute *md_default_attrs[] = {
5642 	&md_level.attr,
5643 	&md_new_level.attr,
5644 	&md_layout.attr,
5645 	&md_raid_disks.attr,
5646 	&md_uuid.attr,
5647 	&md_chunk_size.attr,
5648 	&md_size.attr,
5649 	&md_resync_start.attr,
5650 	&md_metadata.attr,
5651 	&md_new_device.attr,
5652 	&md_safe_delay.attr,
5653 	&md_array_state.attr,
5654 	&md_reshape_position.attr,
5655 	&md_reshape_direction.attr,
5656 	&md_array_size.attr,
5657 	&max_corr_read_errors.attr,
5658 	&md_consistency_policy.attr,
5659 	&md_fail_last_dev.attr,
5660 	&md_serialize_policy.attr,
5661 	NULL,
5662 };
5663 
5664 static const struct attribute_group md_default_group = {
5665 	.attrs = md_default_attrs,
5666 };
5667 
5668 static struct attribute *md_redundancy_attrs[] = {
5669 	&md_scan_mode.attr,
5670 	&md_last_scan_mode.attr,
5671 	&md_mismatches.attr,
5672 	&md_sync_min.attr,
5673 	&md_sync_max.attr,
5674 	&md_sync_speed.attr,
5675 	&md_sync_force_parallel.attr,
5676 	&md_sync_completed.attr,
5677 	&md_min_sync.attr,
5678 	&md_max_sync.attr,
5679 	&md_suspend_lo.attr,
5680 	&md_suspend_hi.attr,
5681 	&md_bitmap.attr,
5682 	&md_degraded.attr,
5683 	NULL,
5684 };
5685 static const struct attribute_group md_redundancy_group = {
5686 	.name = NULL,
5687 	.attrs = md_redundancy_attrs,
5688 };
5689 
5690 static const struct attribute_group *md_attr_groups[] = {
5691 	&md_default_group,
5692 	&md_bitmap_group,
5693 	NULL,
5694 };
5695 
5696 static ssize_t
md_attr_show(struct kobject * kobj,struct attribute * attr,char * page)5697 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
5698 {
5699 	struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
5700 	struct mddev *mddev = container_of(kobj, struct mddev, kobj);
5701 	ssize_t rv;
5702 
5703 	if (!entry->show)
5704 		return -EIO;
5705 	spin_lock(&all_mddevs_lock);
5706 	if (!mddev_get(mddev)) {
5707 		spin_unlock(&all_mddevs_lock);
5708 		return -EBUSY;
5709 	}
5710 	spin_unlock(&all_mddevs_lock);
5711 
5712 	rv = entry->show(mddev, page);
5713 	mddev_put(mddev);
5714 	return rv;
5715 }
5716 
5717 static ssize_t
md_attr_store(struct kobject * kobj,struct attribute * attr,const char * page,size_t length)5718 md_attr_store(struct kobject *kobj, struct attribute *attr,
5719 	      const char *page, size_t length)
5720 {
5721 	struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
5722 	struct mddev *mddev = container_of(kobj, struct mddev, kobj);
5723 	ssize_t rv;
5724 
5725 	if (!entry->store)
5726 		return -EIO;
5727 	if (!capable(CAP_SYS_ADMIN))
5728 		return -EACCES;
5729 	spin_lock(&all_mddevs_lock);
5730 	if (!mddev_get(mddev)) {
5731 		spin_unlock(&all_mddevs_lock);
5732 		return -EBUSY;
5733 	}
5734 	spin_unlock(&all_mddevs_lock);
5735 	rv = entry->store(mddev, page, length);
5736 	mddev_put(mddev);
5737 	return rv;
5738 }
5739 
md_kobj_release(struct kobject * ko)5740 static void md_kobj_release(struct kobject *ko)
5741 {
5742 	struct mddev *mddev = container_of(ko, struct mddev, kobj);
5743 
5744 	if (mddev->sysfs_state)
5745 		sysfs_put(mddev->sysfs_state);
5746 	if (mddev->sysfs_level)
5747 		sysfs_put(mddev->sysfs_level);
5748 
5749 	del_gendisk(mddev->gendisk);
5750 	put_disk(mddev->gendisk);
5751 }
5752 
5753 static const struct sysfs_ops md_sysfs_ops = {
5754 	.show	= md_attr_show,
5755 	.store	= md_attr_store,
5756 };
5757 static const struct kobj_type md_ktype = {
5758 	.release	= md_kobj_release,
5759 	.sysfs_ops	= &md_sysfs_ops,
5760 	.default_groups	= md_attr_groups,
5761 };
5762 
5763 int mdp_major = 0;
5764 
5765 /* stack the limit for all rdevs into lim */
mddev_stack_rdev_limits(struct mddev * mddev,struct queue_limits * lim,unsigned int flags)5766 int mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim,
5767 		unsigned int flags)
5768 {
5769 	struct md_rdev *rdev;
5770 
5771 	rdev_for_each(rdev, mddev) {
5772 		queue_limits_stack_bdev(lim, rdev->bdev, rdev->data_offset,
5773 					mddev->gendisk->disk_name);
5774 		if ((flags & MDDEV_STACK_INTEGRITY) &&
5775 		    !queue_limits_stack_integrity_bdev(lim, rdev->bdev))
5776 			return -EINVAL;
5777 	}
5778 
5779 	return 0;
5780 }
5781 EXPORT_SYMBOL_GPL(mddev_stack_rdev_limits);
5782 
5783 /* apply the extra stacking limits from a new rdev into mddev */
mddev_stack_new_rdev(struct mddev * mddev,struct md_rdev * rdev)5784 int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev)
5785 {
5786 	struct queue_limits lim;
5787 
5788 	if (mddev_is_dm(mddev))
5789 		return 0;
5790 
5791 	lim = queue_limits_start_update(mddev->gendisk->queue);
5792 	queue_limits_stack_bdev(&lim, rdev->bdev, rdev->data_offset,
5793 				mddev->gendisk->disk_name);
5794 
5795 	if (!queue_limits_stack_integrity_bdev(&lim, rdev->bdev)) {
5796 		pr_err("%s: incompatible integrity profile for %pg\n",
5797 		       mdname(mddev), rdev->bdev);
5798 		queue_limits_cancel_update(mddev->gendisk->queue);
5799 		return -ENXIO;
5800 	}
5801 
5802 	return queue_limits_commit_update(mddev->gendisk->queue, &lim);
5803 }
5804 EXPORT_SYMBOL_GPL(mddev_stack_new_rdev);
5805 
5806 /* update the optimal I/O size after a reshape */
mddev_update_io_opt(struct mddev * mddev,unsigned int nr_stripes)5807 void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes)
5808 {
5809 	struct queue_limits lim;
5810 
5811 	if (mddev_is_dm(mddev))
5812 		return;
5813 
5814 	/* don't bother updating io_opt if we can't suspend the array */
5815 	if (mddev_suspend(mddev, false) < 0)
5816 		return;
5817 	lim = queue_limits_start_update(mddev->gendisk->queue);
5818 	lim.io_opt = lim.io_min * nr_stripes;
5819 	queue_limits_commit_update(mddev->gendisk->queue, &lim);
5820 	mddev_resume(mddev);
5821 }
5822 EXPORT_SYMBOL_GPL(mddev_update_io_opt);
5823 
mddev_delayed_delete(struct work_struct * ws)5824 static void mddev_delayed_delete(struct work_struct *ws)
5825 {
5826 	struct mddev *mddev = container_of(ws, struct mddev, del_work);
5827 
5828 	kobject_put(&mddev->kobj);
5829 }
5830 
md_init_stacking_limits(struct queue_limits * lim)5831 void md_init_stacking_limits(struct queue_limits *lim)
5832 {
5833 	blk_set_stacking_limits(lim);
5834 	lim->features = BLK_FEAT_WRITE_CACHE | BLK_FEAT_FUA |
5835 			BLK_FEAT_IO_STAT | BLK_FEAT_NOWAIT;
5836 }
5837 EXPORT_SYMBOL_GPL(md_init_stacking_limits);
5838 
md_alloc(dev_t dev,char * name)5839 struct mddev *md_alloc(dev_t dev, char *name)
5840 {
5841 	/*
5842 	 * If dev is zero, name is the name of a device to allocate with
5843 	 * an arbitrary minor number.  It will be "md_???"
5844 	 * If dev is non-zero it must be a device number with a MAJOR of
5845 	 * MD_MAJOR or mdp_major.  In this case, if "name" is NULL, then
5846 	 * the device is being created by opening a node in /dev.
5847 	 * If "name" is not NULL, the device is being created by
5848 	 * writing to /sys/module/md_mod/parameters/new_array.
5849 	 */
5850 	static DEFINE_MUTEX(disks_mutex);
5851 	struct mddev *mddev;
5852 	struct gendisk *disk;
5853 	int partitioned;
5854 	int shift;
5855 	int unit;
5856 	int error;
5857 
5858 	/*
5859 	 * Wait for any previous instance of this device to be completely
5860 	 * removed (mddev_delayed_delete).
5861 	 */
5862 	flush_workqueue(md_misc_wq);
5863 
5864 	mutex_lock(&disks_mutex);
5865 	mddev = mddev_alloc(dev);
5866 	if (IS_ERR(mddev)) {
5867 		error = PTR_ERR(mddev);
5868 		goto out_unlock;
5869 	}
5870 
5871 	partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
5872 	shift = partitioned ? MdpMinorShift : 0;
5873 	unit = MINOR(mddev->unit) >> shift;
5874 
5875 	if (name && !dev) {
5876 		/* Need to ensure that 'name' is not a duplicate.
5877 		 */
5878 		struct mddev *mddev2;
5879 		spin_lock(&all_mddevs_lock);
5880 
5881 		list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
5882 			if (mddev2->gendisk &&
5883 			    strcmp(mddev2->gendisk->disk_name, name) == 0) {
5884 				spin_unlock(&all_mddevs_lock);
5885 				error = -EEXIST;
5886 				goto out_free_mddev;
5887 			}
5888 		spin_unlock(&all_mddevs_lock);
5889 	}
5890 	if (name && dev)
5891 		/*
5892 		 * Creating /dev/mdNNN via "newarray", so adjust hold_active.
5893 		 */
5894 		mddev->hold_active = UNTIL_STOP;
5895 
5896 	disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
5897 	if (IS_ERR(disk)) {
5898 		error = PTR_ERR(disk);
5899 		goto out_free_mddev;
5900 	}
5901 
5902 	disk->major = MAJOR(mddev->unit);
5903 	disk->first_minor = unit << shift;
5904 	disk->minors = 1 << shift;
5905 	if (name)
5906 		strcpy(disk->disk_name, name);
5907 	else if (partitioned)
5908 		sprintf(disk->disk_name, "md_d%d", unit);
5909 	else
5910 		sprintf(disk->disk_name, "md%d", unit);
5911 	disk->fops = &md_fops;
5912 	disk->private_data = mddev;
5913 
5914 	disk->events |= DISK_EVENT_MEDIA_CHANGE;
5915 	mddev->gendisk = disk;
5916 	error = add_disk(disk);
5917 	if (error)
5918 		goto out_put_disk;
5919 
5920 	kobject_init(&mddev->kobj, &md_ktype);
5921 	error = kobject_add(&mddev->kobj, &disk_to_dev(disk)->kobj, "%s", "md");
5922 	if (error) {
5923 		/*
5924 		 * The disk is already live at this point.  Clear the hold flag
5925 		 * and let mddev_put take care of the deletion, as it isn't any
5926 		 * different from a normal close on last release now.
5927 		 */
5928 		mddev->hold_active = 0;
5929 		mutex_unlock(&disks_mutex);
5930 		mddev_put(mddev);
5931 		return ERR_PTR(error);
5932 	}
5933 
5934 	kobject_uevent(&mddev->kobj, KOBJ_ADD);
5935 	mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
5936 	mddev->sysfs_level = sysfs_get_dirent_safe(mddev->kobj.sd, "level");
5937 	mutex_unlock(&disks_mutex);
5938 	return mddev;
5939 
5940 out_put_disk:
5941 	put_disk(disk);
5942 out_free_mddev:
5943 	mddev_free(mddev);
5944 out_unlock:
5945 	mutex_unlock(&disks_mutex);
5946 	return ERR_PTR(error);
5947 }
5948 
md_alloc_and_put(dev_t dev,char * name)5949 static int md_alloc_and_put(dev_t dev, char *name)
5950 {
5951 	struct mddev *mddev = md_alloc(dev, name);
5952 
5953 	if (IS_ERR(mddev))
5954 		return PTR_ERR(mddev);
5955 	mddev_put(mddev);
5956 	return 0;
5957 }
5958 
md_probe(dev_t dev)5959 static void md_probe(dev_t dev)
5960 {
5961 	if (MAJOR(dev) == MD_MAJOR && MINOR(dev) >= 512)
5962 		return;
5963 	if (create_on_open)
5964 		md_alloc_and_put(dev, NULL);
5965 }
5966 
add_named_array(const char * val,const struct kernel_param * kp)5967 static int add_named_array(const char *val, const struct kernel_param *kp)
5968 {
5969 	/*
5970 	 * val must be "md_*" or "mdNNN".
5971 	 * For "md_*" we allocate an array with a large free minor number, and
5972 	 * set the name to val.  val must not already be an active name.
5973 	 * For "mdNNN" we allocate an array with the minor number NNN
5974 	 * which must not already be in use.
5975 	 */
5976 	int len = strlen(val);
5977 	char buf[DISK_NAME_LEN];
5978 	unsigned long devnum;
5979 
5980 	while (len && val[len-1] == '\n')
5981 		len--;
5982 	if (len >= DISK_NAME_LEN)
5983 		return -E2BIG;
5984 	strscpy(buf, val, len+1);
5985 	if (strncmp(buf, "md_", 3) == 0)
5986 		return md_alloc_and_put(0, buf);
5987 	if (strncmp(buf, "md", 2) == 0 &&
5988 	    isdigit(buf[2]) &&
5989 	    kstrtoul(buf+2, 10, &devnum) == 0 &&
5990 	    devnum <= MINORMASK)
5991 		return md_alloc_and_put(MKDEV(MD_MAJOR, devnum), NULL);
5992 
5993 	return -EINVAL;
5994 }
5995 
md_safemode_timeout(struct timer_list * t)5996 static void md_safemode_timeout(struct timer_list *t)
5997 {
5998 	struct mddev *mddev = from_timer(mddev, t, safemode_timer);
5999 
6000 	mddev->safemode = 1;
6001 	if (mddev->external)
6002 		sysfs_notify_dirent_safe(mddev->sysfs_state);
6003 
6004 	md_wakeup_thread(mddev->thread);
6005 }
6006 
6007 static int start_dirty_degraded;
6008 
md_run(struct mddev * mddev)6009 int md_run(struct mddev *mddev)
6010 {
6011 	int err;
6012 	struct md_rdev *rdev;
6013 	struct md_personality *pers;
6014 	bool nowait = true;
6015 
6016 	if (list_empty(&mddev->disks))
6017 		/* cannot run an array with no devices.. */
6018 		return -EINVAL;
6019 
6020 	if (mddev->pers)
6021 		return -EBUSY;
6022 	/* Cannot run until previous stop completes properly */
6023 	if (mddev->sysfs_active)
6024 		return -EBUSY;
6025 
6026 	/*
6027 	 * Analyze all RAID superblock(s)
6028 	 */
6029 	if (!mddev->raid_disks) {
6030 		if (!mddev->persistent)
6031 			return -EINVAL;
6032 		err = analyze_sbs(mddev);
6033 		if (err)
6034 			return -EINVAL;
6035 	}
6036 
6037 	if (mddev->level != LEVEL_NONE)
6038 		request_module("md-level-%d", mddev->level);
6039 	else if (mddev->clevel[0])
6040 		request_module("md-%s", mddev->clevel);
6041 
6042 	/*
6043 	 * Drop all container device buffers, from now on
6044 	 * the only valid external interface is through the md
6045 	 * device.
6046 	 */
6047 	mddev->has_superblocks = false;
6048 	rdev_for_each(rdev, mddev) {
6049 		if (test_bit(Faulty, &rdev->flags))
6050 			continue;
6051 		sync_blockdev(rdev->bdev);
6052 		invalidate_bdev(rdev->bdev);
6053 		if (mddev->ro != MD_RDONLY && rdev_read_only(rdev)) {
6054 			mddev->ro = MD_RDONLY;
6055 			if (!mddev_is_dm(mddev))
6056 				set_disk_ro(mddev->gendisk, 1);
6057 		}
6058 
6059 		if (rdev->sb_page)
6060 			mddev->has_superblocks = true;
6061 
6062 		/* perform some consistency tests on the device.
6063 		 * We don't want the data to overlap the metadata,
6064 		 * Internal Bitmap issues have been handled elsewhere.
6065 		 */
6066 		if (rdev->meta_bdev) {
6067 			/* Nothing to check */;
6068 		} else if (rdev->data_offset < rdev->sb_start) {
6069 			if (mddev->dev_sectors &&
6070 			    rdev->data_offset + mddev->dev_sectors
6071 			    > rdev->sb_start) {
6072 				pr_warn("md: %s: data overlaps metadata\n",
6073 					mdname(mddev));
6074 				return -EINVAL;
6075 			}
6076 		} else {
6077 			if (rdev->sb_start + rdev->sb_size/512
6078 			    > rdev->data_offset) {
6079 				pr_warn("md: %s: metadata overlaps data\n",
6080 					mdname(mddev));
6081 				return -EINVAL;
6082 			}
6083 		}
6084 		sysfs_notify_dirent_safe(rdev->sysfs_state);
6085 		nowait = nowait && bdev_nowait(rdev->bdev);
6086 	}
6087 
6088 	if (!bioset_initialized(&mddev->bio_set)) {
6089 		err = bioset_init(&mddev->bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
6090 		if (err)
6091 			return err;
6092 	}
6093 	if (!bioset_initialized(&mddev->sync_set)) {
6094 		err = bioset_init(&mddev->sync_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
6095 		if (err)
6096 			goto exit_bio_set;
6097 	}
6098 
6099 	if (!bioset_initialized(&mddev->io_clone_set)) {
6100 		err = bioset_init(&mddev->io_clone_set, BIO_POOL_SIZE,
6101 				  offsetof(struct md_io_clone, bio_clone), 0);
6102 		if (err)
6103 			goto exit_sync_set;
6104 	}
6105 
6106 	pers = get_pers(mddev->level, mddev->clevel);
6107 	if (!pers) {
6108 		err = -EINVAL;
6109 		goto abort;
6110 	}
6111 	if (mddev->level != pers->head.id) {
6112 		mddev->level = pers->head.id;
6113 		mddev->new_level = pers->head.id;
6114 	}
6115 	strscpy(mddev->clevel, pers->head.name, sizeof(mddev->clevel));
6116 
6117 	if (mddev->reshape_position != MaxSector &&
6118 	    pers->start_reshape == NULL) {
6119 		/* This personality cannot handle reshaping... */
6120 		put_pers(pers);
6121 		err = -EINVAL;
6122 		goto abort;
6123 	}
6124 
6125 	if (pers->sync_request) {
6126 		/* Warn if this is a potentially silly
6127 		 * configuration.
6128 		 */
6129 		struct md_rdev *rdev2;
6130 		int warned = 0;
6131 
6132 		rdev_for_each(rdev, mddev)
6133 			rdev_for_each(rdev2, mddev) {
6134 				if (rdev < rdev2 &&
6135 				    rdev->bdev->bd_disk ==
6136 				    rdev2->bdev->bd_disk) {
6137 					pr_warn("%s: WARNING: %pg appears to be on the same physical disk as %pg.\n",
6138 						mdname(mddev),
6139 						rdev->bdev,
6140 						rdev2->bdev);
6141 					warned = 1;
6142 				}
6143 			}
6144 
6145 		if (warned)
6146 			pr_warn("True protection against single-disk failure might be compromised.\n");
6147 	}
6148 
6149 	/* dm-raid expect sync_thread to be frozen until resume */
6150 	if (mddev->gendisk)
6151 		mddev->recovery = 0;
6152 
6153 	/* may be over-ridden by personality */
6154 	mddev->resync_max_sectors = mddev->dev_sectors;
6155 
6156 	mddev->ok_start_degraded = start_dirty_degraded;
6157 
6158 	if (start_readonly && md_is_rdwr(mddev))
6159 		mddev->ro = MD_AUTO_READ; /* read-only, but switch on first write */
6160 
6161 	err = pers->run(mddev);
6162 	if (err)
6163 		pr_warn("md: pers->run() failed ...\n");
6164 	else if (pers->size(mddev, 0, 0) < mddev->array_sectors) {
6165 		WARN_ONCE(!mddev->external_size,
6166 			  "%s: default size too small, but 'external_size' not in effect?\n",
6167 			  __func__);
6168 		pr_warn("md: invalid array_size %llu > default size %llu\n",
6169 			(unsigned long long)mddev->array_sectors / 2,
6170 			(unsigned long long)pers->size(mddev, 0, 0) / 2);
6171 		err = -EINVAL;
6172 	}
6173 	if (err == 0 && pers->sync_request &&
6174 	    (mddev->bitmap_info.file || mddev->bitmap_info.offset)) {
6175 		err = mddev->bitmap_ops->create(mddev, -1);
6176 		if (err)
6177 			pr_warn("%s: failed to create bitmap (%d)\n",
6178 				mdname(mddev), err);
6179 	}
6180 	if (err)
6181 		goto bitmap_abort;
6182 
6183 	if (mddev->bitmap_info.max_write_behind > 0) {
6184 		bool create_pool = false;
6185 
6186 		rdev_for_each(rdev, mddev) {
6187 			if (test_bit(WriteMostly, &rdev->flags) &&
6188 			    rdev_init_serial(rdev))
6189 				create_pool = true;
6190 		}
6191 		if (create_pool && mddev->serial_info_pool == NULL) {
6192 			mddev->serial_info_pool =
6193 				mempool_create_kmalloc_pool(NR_SERIAL_INFOS,
6194 						    sizeof(struct serial_info));
6195 			if (!mddev->serial_info_pool) {
6196 				err = -ENOMEM;
6197 				goto bitmap_abort;
6198 			}
6199 		}
6200 	}
6201 
6202 	if (pers->sync_request) {
6203 		if (mddev->kobj.sd &&
6204 		    sysfs_create_group(&mddev->kobj, &md_redundancy_group))
6205 			pr_warn("md: cannot register extra attributes for %s\n",
6206 				mdname(mddev));
6207 		mddev->sysfs_action = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_action");
6208 		mddev->sysfs_completed = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_completed");
6209 		mddev->sysfs_degraded = sysfs_get_dirent_safe(mddev->kobj.sd, "degraded");
6210 	} else if (mddev->ro == MD_AUTO_READ)
6211 		mddev->ro = MD_RDWR;
6212 
6213 	atomic_set(&mddev->max_corr_read_errors,
6214 		   MD_DEFAULT_MAX_CORRECTED_READ_ERRORS);
6215 	mddev->safemode = 0;
6216 	if (mddev_is_clustered(mddev))
6217 		mddev->safemode_delay = 0;
6218 	else
6219 		mddev->safemode_delay = DEFAULT_SAFEMODE_DELAY;
6220 	mddev->in_sync = 1;
6221 	smp_wmb();
6222 	spin_lock(&mddev->lock);
6223 	mddev->pers = pers;
6224 	spin_unlock(&mddev->lock);
6225 	rdev_for_each(rdev, mddev)
6226 		if (rdev->raid_disk >= 0)
6227 			sysfs_link_rdev(mddev, rdev); /* failure here is OK */
6228 
6229 	if (mddev->degraded && md_is_rdwr(mddev))
6230 		/* This ensures that recovering status is reported immediately
6231 		 * via sysfs - until a lack of spares is confirmed.
6232 		 */
6233 		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6234 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6235 
6236 	if (mddev->sb_flags)
6237 		md_update_sb(mddev, 0);
6238 
6239 	md_new_event();
6240 	return 0;
6241 
6242 bitmap_abort:
6243 	mddev_detach(mddev);
6244 	if (mddev->private)
6245 		pers->free(mddev, mddev->private);
6246 	mddev->private = NULL;
6247 	put_pers(pers);
6248 	mddev->bitmap_ops->destroy(mddev);
6249 abort:
6250 	bioset_exit(&mddev->io_clone_set);
6251 exit_sync_set:
6252 	bioset_exit(&mddev->sync_set);
6253 exit_bio_set:
6254 	bioset_exit(&mddev->bio_set);
6255 	return err;
6256 }
6257 EXPORT_SYMBOL_GPL(md_run);
6258 
do_md_run(struct mddev * mddev)6259 int do_md_run(struct mddev *mddev)
6260 {
6261 	int err;
6262 
6263 	set_bit(MD_NOT_READY, &mddev->flags);
6264 	err = md_run(mddev);
6265 	if (err)
6266 		goto out;
6267 
6268 	err = mddev->bitmap_ops->load(mddev);
6269 	if (err) {
6270 		mddev->bitmap_ops->destroy(mddev);
6271 		goto out;
6272 	}
6273 
6274 	if (mddev_is_clustered(mddev))
6275 		md_allow_write(mddev);
6276 
6277 	/* run start up tasks that require md_thread */
6278 	md_start(mddev);
6279 
6280 	md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
6281 
6282 	set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
6283 	clear_bit(MD_NOT_READY, &mddev->flags);
6284 	mddev->changed = 1;
6285 	kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
6286 	sysfs_notify_dirent_safe(mddev->sysfs_state);
6287 	sysfs_notify_dirent_safe(mddev->sysfs_action);
6288 	sysfs_notify_dirent_safe(mddev->sysfs_degraded);
6289 out:
6290 	clear_bit(MD_NOT_READY, &mddev->flags);
6291 	return err;
6292 }
6293 
md_start(struct mddev * mddev)6294 int md_start(struct mddev *mddev)
6295 {
6296 	int ret = 0;
6297 
6298 	if (mddev->pers->start) {
6299 		set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
6300 		ret = mddev->pers->start(mddev);
6301 		clear_bit(MD_RECOVERY_WAIT, &mddev->recovery);
6302 		md_wakeup_thread(mddev->sync_thread);
6303 	}
6304 	return ret;
6305 }
6306 EXPORT_SYMBOL_GPL(md_start);
6307 
restart_array(struct mddev * mddev)6308 static int restart_array(struct mddev *mddev)
6309 {
6310 	struct gendisk *disk = mddev->gendisk;
6311 	struct md_rdev *rdev;
6312 	bool has_journal = false;
6313 	bool has_readonly = false;
6314 
6315 	/* Complain if it has no devices */
6316 	if (list_empty(&mddev->disks))
6317 		return -ENXIO;
6318 	if (!mddev->pers)
6319 		return -EINVAL;
6320 	if (md_is_rdwr(mddev))
6321 		return -EBUSY;
6322 
6323 	rcu_read_lock();
6324 	rdev_for_each_rcu(rdev, mddev) {
6325 		if (test_bit(Journal, &rdev->flags) &&
6326 		    !test_bit(Faulty, &rdev->flags))
6327 			has_journal = true;
6328 		if (rdev_read_only(rdev))
6329 			has_readonly = true;
6330 	}
6331 	rcu_read_unlock();
6332 	if (test_bit(MD_HAS_JOURNAL, &mddev->flags) && !has_journal)
6333 		/* Don't restart rw with journal missing/faulty */
6334 			return -EINVAL;
6335 	if (has_readonly)
6336 		return -EROFS;
6337 
6338 	mddev->safemode = 0;
6339 	mddev->ro = MD_RDWR;
6340 	set_disk_ro(disk, 0);
6341 	pr_debug("md: %s switched to read-write mode.\n", mdname(mddev));
6342 	/* Kick recovery or resync if necessary */
6343 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6344 	md_wakeup_thread(mddev->sync_thread);
6345 	sysfs_notify_dirent_safe(mddev->sysfs_state);
6346 	return 0;
6347 }
6348 
md_clean(struct mddev * mddev)6349 static void md_clean(struct mddev *mddev)
6350 {
6351 	mddev->array_sectors = 0;
6352 	mddev->external_size = 0;
6353 	mddev->dev_sectors = 0;
6354 	mddev->raid_disks = 0;
6355 	mddev->recovery_cp = 0;
6356 	mddev->resync_min = 0;
6357 	mddev->resync_max = MaxSector;
6358 	mddev->reshape_position = MaxSector;
6359 	/* we still need mddev->external in export_rdev, do not clear it yet */
6360 	mddev->persistent = 0;
6361 	mddev->level = LEVEL_NONE;
6362 	mddev->clevel[0] = 0;
6363 	/*
6364 	 * Don't clear MD_CLOSING, or mddev can be opened again.
6365 	 * 'hold_active != 0' means mddev is still in the creation
6366 	 * process and will be used later.
6367 	 */
6368 	if (mddev->hold_active)
6369 		mddev->flags = 0;
6370 	else
6371 		mddev->flags &= BIT_ULL_MASK(MD_CLOSING);
6372 	mddev->sb_flags = 0;
6373 	mddev->ro = MD_RDWR;
6374 	mddev->metadata_type[0] = 0;
6375 	mddev->chunk_sectors = 0;
6376 	mddev->ctime = mddev->utime = 0;
6377 	mddev->layout = 0;
6378 	mddev->max_disks = 0;
6379 	mddev->events = 0;
6380 	mddev->can_decrease_events = 0;
6381 	mddev->delta_disks = 0;
6382 	mddev->reshape_backwards = 0;
6383 	mddev->new_level = LEVEL_NONE;
6384 	mddev->new_layout = 0;
6385 	mddev->new_chunk_sectors = 0;
6386 	mddev->curr_resync = MD_RESYNC_NONE;
6387 	atomic64_set(&mddev->resync_mismatches, 0);
6388 	mddev->suspend_lo = mddev->suspend_hi = 0;
6389 	mddev->sync_speed_min = mddev->sync_speed_max = 0;
6390 	mddev->recovery = 0;
6391 	mddev->in_sync = 0;
6392 	mddev->changed = 0;
6393 	mddev->degraded = 0;
6394 	mddev->safemode = 0;
6395 	mddev->private = NULL;
6396 	mddev->cluster_info = NULL;
6397 	mddev->bitmap_info.offset = 0;
6398 	mddev->bitmap_info.default_offset = 0;
6399 	mddev->bitmap_info.default_space = 0;
6400 	mddev->bitmap_info.chunksize = 0;
6401 	mddev->bitmap_info.daemon_sleep = 0;
6402 	mddev->bitmap_info.max_write_behind = 0;
6403 	mddev->bitmap_info.nodes = 0;
6404 }
6405 
__md_stop_writes(struct mddev * mddev)6406 static void __md_stop_writes(struct mddev *mddev)
6407 {
6408 	del_timer_sync(&mddev->safemode_timer);
6409 
6410 	if (mddev->pers && mddev->pers->quiesce) {
6411 		mddev->pers->quiesce(mddev, 1);
6412 		mddev->pers->quiesce(mddev, 0);
6413 	}
6414 
6415 	mddev->bitmap_ops->flush(mddev);
6416 
6417 	if (md_is_rdwr(mddev) &&
6418 	    ((!mddev->in_sync && !mddev_is_clustered(mddev)) ||
6419 	     mddev->sb_flags)) {
6420 		/* mark array as shutdown cleanly */
6421 		if (!mddev_is_clustered(mddev))
6422 			mddev->in_sync = 1;
6423 		md_update_sb(mddev, 1);
6424 	}
6425 	/* disable policy to guarantee rdevs free resources for serialization */
6426 	mddev->serialize_policy = 0;
6427 	mddev_destroy_serial_pool(mddev, NULL);
6428 }
6429 
md_stop_writes(struct mddev * mddev)6430 void md_stop_writes(struct mddev *mddev)
6431 {
6432 	mddev_lock_nointr(mddev);
6433 	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6434 	stop_sync_thread(mddev, true);
6435 	__md_stop_writes(mddev);
6436 	mddev_unlock(mddev);
6437 }
6438 EXPORT_SYMBOL_GPL(md_stop_writes);
6439 
mddev_detach(struct mddev * mddev)6440 static void mddev_detach(struct mddev *mddev)
6441 {
6442 	mddev->bitmap_ops->wait_behind_writes(mddev);
6443 	if (mddev->pers && mddev->pers->quiesce && !is_md_suspended(mddev)) {
6444 		mddev->pers->quiesce(mddev, 1);
6445 		mddev->pers->quiesce(mddev, 0);
6446 	}
6447 	md_unregister_thread(mddev, &mddev->thread);
6448 
6449 	/* the unplug fn references 'conf' */
6450 	if (!mddev_is_dm(mddev))
6451 		blk_sync_queue(mddev->gendisk->queue);
6452 }
6453 
__md_stop(struct mddev * mddev)6454 static void __md_stop(struct mddev *mddev)
6455 {
6456 	struct md_personality *pers = mddev->pers;
6457 
6458 	mddev->bitmap_ops->destroy(mddev);
6459 	mddev_detach(mddev);
6460 	spin_lock(&mddev->lock);
6461 	mddev->pers = NULL;
6462 	spin_unlock(&mddev->lock);
6463 	if (mddev->private)
6464 		pers->free(mddev, mddev->private);
6465 	mddev->private = NULL;
6466 	if (pers->sync_request && mddev->to_remove == NULL)
6467 		mddev->to_remove = &md_redundancy_group;
6468 	put_pers(pers);
6469 	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6470 
6471 	bioset_exit(&mddev->bio_set);
6472 	bioset_exit(&mddev->sync_set);
6473 	bioset_exit(&mddev->io_clone_set);
6474 }
6475 
md_stop(struct mddev * mddev)6476 void md_stop(struct mddev *mddev)
6477 {
6478 	lockdep_assert_held(&mddev->reconfig_mutex);
6479 
6480 	/* stop the array and free an attached data structures.
6481 	 * This is called from dm-raid
6482 	 */
6483 	__md_stop_writes(mddev);
6484 	__md_stop(mddev);
6485 }
6486 
6487 EXPORT_SYMBOL_GPL(md_stop);
6488 
6489 /* ensure 'mddev->pers' exist before calling md_set_readonly() */
md_set_readonly(struct mddev * mddev)6490 static int md_set_readonly(struct mddev *mddev)
6491 {
6492 	int err = 0;
6493 	int did_freeze = 0;
6494 
6495 	if (mddev->external && test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
6496 		return -EBUSY;
6497 
6498 	if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
6499 		did_freeze = 1;
6500 		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6501 	}
6502 
6503 	stop_sync_thread(mddev, false);
6504 	wait_event(mddev->sb_wait,
6505 		   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
6506 	mddev_lock_nointr(mddev);
6507 
6508 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
6509 		pr_warn("md: %s still in use.\n",mdname(mddev));
6510 		err = -EBUSY;
6511 		goto out;
6512 	}
6513 
6514 	__md_stop_writes(mddev);
6515 
6516 	if (mddev->ro == MD_RDONLY) {
6517 		err  = -ENXIO;
6518 		goto out;
6519 	}
6520 
6521 	mddev->ro = MD_RDONLY;
6522 	set_disk_ro(mddev->gendisk, 1);
6523 
6524 out:
6525 	if (!err || did_freeze) {
6526 		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6527 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6528 		sysfs_notify_dirent_safe(mddev->sysfs_state);
6529 	}
6530 
6531 	return err;
6532 }
6533 
6534 /* mode:
6535  *   0 - completely stop and dis-assemble array
6536  *   2 - stop but do not disassemble array
6537  */
do_md_stop(struct mddev * mddev,int mode)6538 static int do_md_stop(struct mddev *mddev, int mode)
6539 {
6540 	struct gendisk *disk = mddev->gendisk;
6541 	struct md_rdev *rdev;
6542 	int did_freeze = 0;
6543 
6544 	if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
6545 		did_freeze = 1;
6546 		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6547 	}
6548 
6549 	stop_sync_thread(mddev, true);
6550 
6551 	if (mddev->sysfs_active ||
6552 	    test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
6553 		pr_warn("md: %s still in use.\n",mdname(mddev));
6554 		if (did_freeze) {
6555 			clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6556 			set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6557 		}
6558 		return -EBUSY;
6559 	}
6560 	if (mddev->pers) {
6561 		if (!md_is_rdwr(mddev))
6562 			set_disk_ro(disk, 0);
6563 
6564 		__md_stop_writes(mddev);
6565 		__md_stop(mddev);
6566 
6567 		/* tell userspace to handle 'inactive' */
6568 		sysfs_notify_dirent_safe(mddev->sysfs_state);
6569 
6570 		rdev_for_each(rdev, mddev)
6571 			if (rdev->raid_disk >= 0)
6572 				sysfs_unlink_rdev(mddev, rdev);
6573 
6574 		set_capacity_and_notify(disk, 0);
6575 		mddev->changed = 1;
6576 
6577 		if (!md_is_rdwr(mddev))
6578 			mddev->ro = MD_RDWR;
6579 	}
6580 	/*
6581 	 * Free resources if final stop
6582 	 */
6583 	if (mode == 0) {
6584 		pr_info("md: %s stopped.\n", mdname(mddev));
6585 
6586 		if (mddev->bitmap_info.file) {
6587 			struct file *f = mddev->bitmap_info.file;
6588 			spin_lock(&mddev->lock);
6589 			mddev->bitmap_info.file = NULL;
6590 			spin_unlock(&mddev->lock);
6591 			fput(f);
6592 		}
6593 		mddev->bitmap_info.offset = 0;
6594 
6595 		export_array(mddev);
6596 
6597 		md_clean(mddev);
6598 		if (mddev->hold_active == UNTIL_STOP)
6599 			mddev->hold_active = 0;
6600 	}
6601 	md_new_event();
6602 	sysfs_notify_dirent_safe(mddev->sysfs_state);
6603 	return 0;
6604 }
6605 
6606 #ifndef MODULE
autorun_array(struct mddev * mddev)6607 static void autorun_array(struct mddev *mddev)
6608 {
6609 	struct md_rdev *rdev;
6610 	int err;
6611 
6612 	if (list_empty(&mddev->disks))
6613 		return;
6614 
6615 	pr_info("md: running: ");
6616 
6617 	rdev_for_each(rdev, mddev) {
6618 		pr_cont("<%pg>", rdev->bdev);
6619 	}
6620 	pr_cont("\n");
6621 
6622 	err = do_md_run(mddev);
6623 	if (err) {
6624 		pr_warn("md: do_md_run() returned %d\n", err);
6625 		do_md_stop(mddev, 0);
6626 	}
6627 }
6628 
6629 /*
6630  * lets try to run arrays based on all disks that have arrived
6631  * until now. (those are in pending_raid_disks)
6632  *
6633  * the method: pick the first pending disk, collect all disks with
6634  * the same UUID, remove all from the pending list and put them into
6635  * the 'same_array' list. Then order this list based on superblock
6636  * update time (freshest comes first), kick out 'old' disks and
6637  * compare superblocks. If everything's fine then run it.
6638  *
6639  * If "unit" is allocated, then bump its reference count
6640  */
autorun_devices(int part)6641 static void autorun_devices(int part)
6642 {
6643 	struct md_rdev *rdev0, *rdev, *tmp;
6644 	struct mddev *mddev;
6645 
6646 	pr_info("md: autorun ...\n");
6647 	while (!list_empty(&pending_raid_disks)) {
6648 		int unit;
6649 		dev_t dev;
6650 		LIST_HEAD(candidates);
6651 		rdev0 = list_entry(pending_raid_disks.next,
6652 					 struct md_rdev, same_set);
6653 
6654 		pr_debug("md: considering %pg ...\n", rdev0->bdev);
6655 		INIT_LIST_HEAD(&candidates);
6656 		rdev_for_each_list(rdev, tmp, &pending_raid_disks)
6657 			if (super_90_load(rdev, rdev0, 0) >= 0) {
6658 				pr_debug("md:  adding %pg ...\n",
6659 					 rdev->bdev);
6660 				list_move(&rdev->same_set, &candidates);
6661 			}
6662 		/*
6663 		 * now we have a set of devices, with all of them having
6664 		 * mostly sane superblocks. It's time to allocate the
6665 		 * mddev.
6666 		 */
6667 		if (part) {
6668 			dev = MKDEV(mdp_major,
6669 				    rdev0->preferred_minor << MdpMinorShift);
6670 			unit = MINOR(dev) >> MdpMinorShift;
6671 		} else {
6672 			dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
6673 			unit = MINOR(dev);
6674 		}
6675 		if (rdev0->preferred_minor != unit) {
6676 			pr_warn("md: unit number in %pg is bad: %d\n",
6677 				rdev0->bdev, rdev0->preferred_minor);
6678 			break;
6679 		}
6680 
6681 		mddev = md_alloc(dev, NULL);
6682 		if (IS_ERR(mddev))
6683 			break;
6684 
6685 		if (mddev_suspend_and_lock(mddev))
6686 			pr_warn("md: %s locked, cannot run\n", mdname(mddev));
6687 		else if (mddev->raid_disks || mddev->major_version
6688 			 || !list_empty(&mddev->disks)) {
6689 			pr_warn("md: %s already running, cannot run %pg\n",
6690 				mdname(mddev), rdev0->bdev);
6691 			mddev_unlock_and_resume(mddev);
6692 		} else {
6693 			pr_debug("md: created %s\n", mdname(mddev));
6694 			mddev->persistent = 1;
6695 			rdev_for_each_list(rdev, tmp, &candidates) {
6696 				list_del_init(&rdev->same_set);
6697 				if (bind_rdev_to_array(rdev, mddev))
6698 					export_rdev(rdev, mddev);
6699 			}
6700 			autorun_array(mddev);
6701 			mddev_unlock_and_resume(mddev);
6702 		}
6703 		/* on success, candidates will be empty, on error
6704 		 * it won't...
6705 		 */
6706 		rdev_for_each_list(rdev, tmp, &candidates) {
6707 			list_del_init(&rdev->same_set);
6708 			export_rdev(rdev, mddev);
6709 		}
6710 		mddev_put(mddev);
6711 	}
6712 	pr_info("md: ... autorun DONE.\n");
6713 }
6714 #endif /* !MODULE */
6715 
get_version(void __user * arg)6716 static int get_version(void __user *arg)
6717 {
6718 	mdu_version_t ver;
6719 
6720 	ver.major = MD_MAJOR_VERSION;
6721 	ver.minor = MD_MINOR_VERSION;
6722 	ver.patchlevel = MD_PATCHLEVEL_VERSION;
6723 
6724 	if (copy_to_user(arg, &ver, sizeof(ver)))
6725 		return -EFAULT;
6726 
6727 	return 0;
6728 }
6729 
get_array_info(struct mddev * mddev,void __user * arg)6730 static int get_array_info(struct mddev *mddev, void __user *arg)
6731 {
6732 	mdu_array_info_t info;
6733 	int nr,working,insync,failed,spare;
6734 	struct md_rdev *rdev;
6735 
6736 	nr = working = insync = failed = spare = 0;
6737 	rcu_read_lock();
6738 	rdev_for_each_rcu(rdev, mddev) {
6739 		nr++;
6740 		if (test_bit(Faulty, &rdev->flags))
6741 			failed++;
6742 		else {
6743 			working++;
6744 			if (test_bit(In_sync, &rdev->flags))
6745 				insync++;
6746 			else if (test_bit(Journal, &rdev->flags))
6747 				/* TODO: add journal count to md_u.h */
6748 				;
6749 			else
6750 				spare++;
6751 		}
6752 	}
6753 	rcu_read_unlock();
6754 
6755 	info.major_version = mddev->major_version;
6756 	info.minor_version = mddev->minor_version;
6757 	info.patch_version = MD_PATCHLEVEL_VERSION;
6758 	info.ctime         = clamp_t(time64_t, mddev->ctime, 0, U32_MAX);
6759 	info.level         = mddev->level;
6760 	info.size          = mddev->dev_sectors / 2;
6761 	if (info.size != mddev->dev_sectors / 2) /* overflow */
6762 		info.size = -1;
6763 	info.nr_disks      = nr;
6764 	info.raid_disks    = mddev->raid_disks;
6765 	info.md_minor      = mddev->md_minor;
6766 	info.not_persistent= !mddev->persistent;
6767 
6768 	info.utime         = clamp_t(time64_t, mddev->utime, 0, U32_MAX);
6769 	info.state         = 0;
6770 	if (mddev->in_sync)
6771 		info.state = (1<<MD_SB_CLEAN);
6772 	if (mddev->bitmap && mddev->bitmap_info.offset)
6773 		info.state |= (1<<MD_SB_BITMAP_PRESENT);
6774 	if (mddev_is_clustered(mddev))
6775 		info.state |= (1<<MD_SB_CLUSTERED);
6776 	info.active_disks  = insync;
6777 	info.working_disks = working;
6778 	info.failed_disks  = failed;
6779 	info.spare_disks   = spare;
6780 
6781 	info.layout        = mddev->layout;
6782 	info.chunk_size    = mddev->chunk_sectors << 9;
6783 
6784 	if (copy_to_user(arg, &info, sizeof(info)))
6785 		return -EFAULT;
6786 
6787 	return 0;
6788 }
6789 
get_bitmap_file(struct mddev * mddev,void __user * arg)6790 static int get_bitmap_file(struct mddev *mddev, void __user * arg)
6791 {
6792 	mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
6793 	char *ptr;
6794 	int err;
6795 
6796 	file = kzalloc(sizeof(*file), GFP_NOIO);
6797 	if (!file)
6798 		return -ENOMEM;
6799 
6800 	err = 0;
6801 	spin_lock(&mddev->lock);
6802 	/* bitmap enabled */
6803 	if (mddev->bitmap_info.file) {
6804 		ptr = file_path(mddev->bitmap_info.file, file->pathname,
6805 				sizeof(file->pathname));
6806 		if (IS_ERR(ptr))
6807 			err = PTR_ERR(ptr);
6808 		else
6809 			memmove(file->pathname, ptr,
6810 				sizeof(file->pathname)-(ptr-file->pathname));
6811 	}
6812 	spin_unlock(&mddev->lock);
6813 
6814 	if (err == 0 &&
6815 	    copy_to_user(arg, file, sizeof(*file)))
6816 		err = -EFAULT;
6817 
6818 	kfree(file);
6819 	return err;
6820 }
6821 
get_disk_info(struct mddev * mddev,void __user * arg)6822 static int get_disk_info(struct mddev *mddev, void __user * arg)
6823 {
6824 	mdu_disk_info_t info;
6825 	struct md_rdev *rdev;
6826 
6827 	if (copy_from_user(&info, arg, sizeof(info)))
6828 		return -EFAULT;
6829 
6830 	rcu_read_lock();
6831 	rdev = md_find_rdev_nr_rcu(mddev, info.number);
6832 	if (rdev) {
6833 		info.major = MAJOR(rdev->bdev->bd_dev);
6834 		info.minor = MINOR(rdev->bdev->bd_dev);
6835 		info.raid_disk = rdev->raid_disk;
6836 		info.state = 0;
6837 		if (test_bit(Faulty, &rdev->flags))
6838 			info.state |= (1<<MD_DISK_FAULTY);
6839 		else if (test_bit(In_sync, &rdev->flags)) {
6840 			info.state |= (1<<MD_DISK_ACTIVE);
6841 			info.state |= (1<<MD_DISK_SYNC);
6842 		}
6843 		if (test_bit(Journal, &rdev->flags))
6844 			info.state |= (1<<MD_DISK_JOURNAL);
6845 		if (test_bit(WriteMostly, &rdev->flags))
6846 			info.state |= (1<<MD_DISK_WRITEMOSTLY);
6847 		if (test_bit(FailFast, &rdev->flags))
6848 			info.state |= (1<<MD_DISK_FAILFAST);
6849 	} else {
6850 		info.major = info.minor = 0;
6851 		info.raid_disk = -1;
6852 		info.state = (1<<MD_DISK_REMOVED);
6853 	}
6854 	rcu_read_unlock();
6855 
6856 	if (copy_to_user(arg, &info, sizeof(info)))
6857 		return -EFAULT;
6858 
6859 	return 0;
6860 }
6861 
md_add_new_disk(struct mddev * mddev,struct mdu_disk_info_s * info)6862 int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info)
6863 {
6864 	struct md_rdev *rdev;
6865 	dev_t dev = MKDEV(info->major,info->minor);
6866 
6867 	if (mddev_is_clustered(mddev) &&
6868 		!(info->state & ((1 << MD_DISK_CLUSTER_ADD) | (1 << MD_DISK_CANDIDATE)))) {
6869 		pr_warn("%s: Cannot add to clustered mddev.\n",
6870 			mdname(mddev));
6871 		return -EINVAL;
6872 	}
6873 
6874 	if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
6875 		return -EOVERFLOW;
6876 
6877 	if (!mddev->raid_disks) {
6878 		int err;
6879 		/* expecting a device which has a superblock */
6880 		rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
6881 		if (IS_ERR(rdev)) {
6882 			pr_warn("md: md_import_device returned %ld\n",
6883 				PTR_ERR(rdev));
6884 			return PTR_ERR(rdev);
6885 		}
6886 		if (!list_empty(&mddev->disks)) {
6887 			struct md_rdev *rdev0
6888 				= list_entry(mddev->disks.next,
6889 					     struct md_rdev, same_set);
6890 			err = super_types[mddev->major_version]
6891 				.load_super(rdev, rdev0, mddev->minor_version);
6892 			if (err < 0) {
6893 				pr_warn("md: %pg has different UUID to %pg\n",
6894 					rdev->bdev,
6895 					rdev0->bdev);
6896 				export_rdev(rdev, mddev);
6897 				return -EINVAL;
6898 			}
6899 		}
6900 		err = bind_rdev_to_array(rdev, mddev);
6901 		if (err)
6902 			export_rdev(rdev, mddev);
6903 		return err;
6904 	}
6905 
6906 	/*
6907 	 * md_add_new_disk can be used once the array is assembled
6908 	 * to add "hot spares".  They must already have a superblock
6909 	 * written
6910 	 */
6911 	if (mddev->pers) {
6912 		int err;
6913 		if (!mddev->pers->hot_add_disk) {
6914 			pr_warn("%s: personality does not support diskops!\n",
6915 				mdname(mddev));
6916 			return -EINVAL;
6917 		}
6918 		if (mddev->persistent)
6919 			rdev = md_import_device(dev, mddev->major_version,
6920 						mddev->minor_version);
6921 		else
6922 			rdev = md_import_device(dev, -1, -1);
6923 		if (IS_ERR(rdev)) {
6924 			pr_warn("md: md_import_device returned %ld\n",
6925 				PTR_ERR(rdev));
6926 			return PTR_ERR(rdev);
6927 		}
6928 		/* set saved_raid_disk if appropriate */
6929 		if (!mddev->persistent) {
6930 			if (info->state & (1<<MD_DISK_SYNC)  &&
6931 			    info->raid_disk < mddev->raid_disks) {
6932 				rdev->raid_disk = info->raid_disk;
6933 				clear_bit(Bitmap_sync, &rdev->flags);
6934 			} else
6935 				rdev->raid_disk = -1;
6936 			rdev->saved_raid_disk = rdev->raid_disk;
6937 		} else
6938 			super_types[mddev->major_version].
6939 				validate_super(mddev, NULL/*freshest*/, rdev);
6940 		if ((info->state & (1<<MD_DISK_SYNC)) &&
6941 		     rdev->raid_disk != info->raid_disk) {
6942 			/* This was a hot-add request, but events doesn't
6943 			 * match, so reject it.
6944 			 */
6945 			export_rdev(rdev, mddev);
6946 			return -EINVAL;
6947 		}
6948 
6949 		clear_bit(In_sync, &rdev->flags); /* just to be sure */
6950 		if (info->state & (1<<MD_DISK_WRITEMOSTLY))
6951 			set_bit(WriteMostly, &rdev->flags);
6952 		else
6953 			clear_bit(WriteMostly, &rdev->flags);
6954 		if (info->state & (1<<MD_DISK_FAILFAST))
6955 			set_bit(FailFast, &rdev->flags);
6956 		else
6957 			clear_bit(FailFast, &rdev->flags);
6958 
6959 		if (info->state & (1<<MD_DISK_JOURNAL)) {
6960 			struct md_rdev *rdev2;
6961 			bool has_journal = false;
6962 
6963 			/* make sure no existing journal disk */
6964 			rdev_for_each(rdev2, mddev) {
6965 				if (test_bit(Journal, &rdev2->flags)) {
6966 					has_journal = true;
6967 					break;
6968 				}
6969 			}
6970 			if (has_journal || mddev->bitmap) {
6971 				export_rdev(rdev, mddev);
6972 				return -EBUSY;
6973 			}
6974 			set_bit(Journal, &rdev->flags);
6975 		}
6976 		/*
6977 		 * check whether the device shows up in other nodes
6978 		 */
6979 		if (mddev_is_clustered(mddev)) {
6980 			if (info->state & (1 << MD_DISK_CANDIDATE))
6981 				set_bit(Candidate, &rdev->flags);
6982 			else if (info->state & (1 << MD_DISK_CLUSTER_ADD)) {
6983 				/* --add initiated by this node */
6984 				err = mddev->cluster_ops->add_new_disk(mddev, rdev);
6985 				if (err) {
6986 					export_rdev(rdev, mddev);
6987 					return err;
6988 				}
6989 			}
6990 		}
6991 
6992 		rdev->raid_disk = -1;
6993 		err = bind_rdev_to_array(rdev, mddev);
6994 
6995 		if (err)
6996 			export_rdev(rdev, mddev);
6997 
6998 		if (mddev_is_clustered(mddev)) {
6999 			if (info->state & (1 << MD_DISK_CANDIDATE)) {
7000 				if (!err) {
7001 					err = mddev->cluster_ops->new_disk_ack(
7002 							mddev, err == 0);
7003 					if (err)
7004 						md_kick_rdev_from_array(rdev);
7005 				}
7006 			} else {
7007 				if (err)
7008 					mddev->cluster_ops->add_new_disk_cancel(mddev);
7009 				else
7010 					err = add_bound_rdev(rdev);
7011 			}
7012 
7013 		} else if (!err)
7014 			err = add_bound_rdev(rdev);
7015 
7016 		return err;
7017 	}
7018 
7019 	/* otherwise, md_add_new_disk is only allowed
7020 	 * for major_version==0 superblocks
7021 	 */
7022 	if (mddev->major_version != 0) {
7023 		pr_warn("%s: ADD_NEW_DISK not supported\n", mdname(mddev));
7024 		return -EINVAL;
7025 	}
7026 
7027 	if (!(info->state & (1<<MD_DISK_FAULTY))) {
7028 		int err;
7029 		rdev = md_import_device(dev, -1, 0);
7030 		if (IS_ERR(rdev)) {
7031 			pr_warn("md: error, md_import_device() returned %ld\n",
7032 				PTR_ERR(rdev));
7033 			return PTR_ERR(rdev);
7034 		}
7035 		rdev->desc_nr = info->number;
7036 		if (info->raid_disk < mddev->raid_disks)
7037 			rdev->raid_disk = info->raid_disk;
7038 		else
7039 			rdev->raid_disk = -1;
7040 
7041 		if (rdev->raid_disk < mddev->raid_disks)
7042 			if (info->state & (1<<MD_DISK_SYNC))
7043 				set_bit(In_sync, &rdev->flags);
7044 
7045 		if (info->state & (1<<MD_DISK_WRITEMOSTLY))
7046 			set_bit(WriteMostly, &rdev->flags);
7047 		if (info->state & (1<<MD_DISK_FAILFAST))
7048 			set_bit(FailFast, &rdev->flags);
7049 
7050 		if (!mddev->persistent) {
7051 			pr_debug("md: nonpersistent superblock ...\n");
7052 			rdev->sb_start = bdev_nr_sectors(rdev->bdev);
7053 		} else
7054 			rdev->sb_start = calc_dev_sboffset(rdev);
7055 		rdev->sectors = rdev->sb_start;
7056 
7057 		err = bind_rdev_to_array(rdev, mddev);
7058 		if (err) {
7059 			export_rdev(rdev, mddev);
7060 			return err;
7061 		}
7062 	}
7063 
7064 	return 0;
7065 }
7066 
hot_remove_disk(struct mddev * mddev,dev_t dev)7067 static int hot_remove_disk(struct mddev *mddev, dev_t dev)
7068 {
7069 	struct md_rdev *rdev;
7070 
7071 	if (!mddev->pers)
7072 		return -ENODEV;
7073 
7074 	rdev = find_rdev(mddev, dev);
7075 	if (!rdev)
7076 		return -ENXIO;
7077 
7078 	if (rdev->raid_disk < 0)
7079 		goto kick_rdev;
7080 
7081 	clear_bit(Blocked, &rdev->flags);
7082 	remove_and_add_spares(mddev, rdev);
7083 
7084 	if (rdev->raid_disk >= 0)
7085 		goto busy;
7086 
7087 kick_rdev:
7088 	if (mddev_is_clustered(mddev) &&
7089 	    mddev->cluster_ops->remove_disk(mddev, rdev))
7090 		goto busy;
7091 
7092 	md_kick_rdev_from_array(rdev);
7093 	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
7094 	if (!mddev->thread)
7095 		md_update_sb(mddev, 1);
7096 	md_new_event();
7097 
7098 	return 0;
7099 busy:
7100 	pr_debug("md: cannot remove active disk %pg from %s ...\n",
7101 		 rdev->bdev, mdname(mddev));
7102 	return -EBUSY;
7103 }
7104 
hot_add_disk(struct mddev * mddev,dev_t dev)7105 static int hot_add_disk(struct mddev *mddev, dev_t dev)
7106 {
7107 	int err;
7108 	struct md_rdev *rdev;
7109 
7110 	if (!mddev->pers)
7111 		return -ENODEV;
7112 
7113 	if (mddev->major_version != 0) {
7114 		pr_warn("%s: HOT_ADD may only be used with version-0 superblocks.\n",
7115 			mdname(mddev));
7116 		return -EINVAL;
7117 	}
7118 	if (!mddev->pers->hot_add_disk) {
7119 		pr_warn("%s: personality does not support diskops!\n",
7120 			mdname(mddev));
7121 		return -EINVAL;
7122 	}
7123 
7124 	rdev = md_import_device(dev, -1, 0);
7125 	if (IS_ERR(rdev)) {
7126 		pr_warn("md: error, md_import_device() returned %ld\n",
7127 			PTR_ERR(rdev));
7128 		return -EINVAL;
7129 	}
7130 
7131 	if (mddev->persistent)
7132 		rdev->sb_start = calc_dev_sboffset(rdev);
7133 	else
7134 		rdev->sb_start = bdev_nr_sectors(rdev->bdev);
7135 
7136 	rdev->sectors = rdev->sb_start;
7137 
7138 	if (test_bit(Faulty, &rdev->flags)) {
7139 		pr_warn("md: can not hot-add faulty %pg disk to %s!\n",
7140 			rdev->bdev, mdname(mddev));
7141 		err = -EINVAL;
7142 		goto abort_export;
7143 	}
7144 
7145 	clear_bit(In_sync, &rdev->flags);
7146 	rdev->desc_nr = -1;
7147 	rdev->saved_raid_disk = -1;
7148 	err = bind_rdev_to_array(rdev, mddev);
7149 	if (err)
7150 		goto abort_export;
7151 
7152 	/*
7153 	 * The rest should better be atomic, we can have disk failures
7154 	 * noticed in interrupt contexts ...
7155 	 */
7156 
7157 	rdev->raid_disk = -1;
7158 
7159 	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
7160 	if (!mddev->thread)
7161 		md_update_sb(mddev, 1);
7162 	/*
7163 	 * Kick recovery, maybe this spare has to be added to the
7164 	 * array immediately.
7165 	 */
7166 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7167 	md_new_event();
7168 	return 0;
7169 
7170 abort_export:
7171 	export_rdev(rdev, mddev);
7172 	return err;
7173 }
7174 
set_bitmap_file(struct mddev * mddev,int fd)7175 static int set_bitmap_file(struct mddev *mddev, int fd)
7176 {
7177 	int err = 0;
7178 
7179 	if (mddev->pers) {
7180 		if (!mddev->pers->quiesce || !mddev->thread)
7181 			return -EBUSY;
7182 		if (mddev->recovery || mddev->sync_thread)
7183 			return -EBUSY;
7184 		/* we should be able to change the bitmap.. */
7185 	}
7186 
7187 	if (fd >= 0) {
7188 		struct inode *inode;
7189 		struct file *f;
7190 
7191 		if (mddev->bitmap || mddev->bitmap_info.file)
7192 			return -EEXIST; /* cannot add when bitmap is present */
7193 
7194 		if (!IS_ENABLED(CONFIG_MD_BITMAP_FILE)) {
7195 			pr_warn("%s: bitmap files not supported by this kernel\n",
7196 				mdname(mddev));
7197 			return -EINVAL;
7198 		}
7199 		pr_warn("%s: using deprecated bitmap file support\n",
7200 			mdname(mddev));
7201 
7202 		f = fget(fd);
7203 
7204 		if (f == NULL) {
7205 			pr_warn("%s: error: failed to get bitmap file\n",
7206 				mdname(mddev));
7207 			return -EBADF;
7208 		}
7209 
7210 		inode = f->f_mapping->host;
7211 		if (!S_ISREG(inode->i_mode)) {
7212 			pr_warn("%s: error: bitmap file must be a regular file\n",
7213 				mdname(mddev));
7214 			err = -EBADF;
7215 		} else if (!(f->f_mode & FMODE_WRITE)) {
7216 			pr_warn("%s: error: bitmap file must open for write\n",
7217 				mdname(mddev));
7218 			err = -EBADF;
7219 		} else if (atomic_read(&inode->i_writecount) != 1) {
7220 			pr_warn("%s: error: bitmap file is already in use\n",
7221 				mdname(mddev));
7222 			err = -EBUSY;
7223 		}
7224 		if (err) {
7225 			fput(f);
7226 			return err;
7227 		}
7228 		mddev->bitmap_info.file = f;
7229 		mddev->bitmap_info.offset = 0; /* file overrides offset */
7230 	} else if (mddev->bitmap == NULL)
7231 		return -ENOENT; /* cannot remove what isn't there */
7232 	err = 0;
7233 	if (mddev->pers) {
7234 		if (fd >= 0) {
7235 			err = mddev->bitmap_ops->create(mddev, -1);
7236 			if (!err)
7237 				err = mddev->bitmap_ops->load(mddev);
7238 
7239 			if (err) {
7240 				mddev->bitmap_ops->destroy(mddev);
7241 				fd = -1;
7242 			}
7243 		} else if (fd < 0) {
7244 			mddev->bitmap_ops->destroy(mddev);
7245 		}
7246 	}
7247 
7248 	if (fd < 0) {
7249 		struct file *f = mddev->bitmap_info.file;
7250 		if (f) {
7251 			spin_lock(&mddev->lock);
7252 			mddev->bitmap_info.file = NULL;
7253 			spin_unlock(&mddev->lock);
7254 			fput(f);
7255 		}
7256 	}
7257 
7258 	return err;
7259 }
7260 
7261 /*
7262  * md_set_array_info is used two different ways
7263  * The original usage is when creating a new array.
7264  * In this usage, raid_disks is > 0 and it together with
7265  *  level, size, not_persistent,layout,chunksize determine the
7266  *  shape of the array.
7267  *  This will always create an array with a type-0.90.0 superblock.
7268  * The newer usage is when assembling an array.
7269  *  In this case raid_disks will be 0, and the major_version field is
7270  *  use to determine which style super-blocks are to be found on the devices.
7271  *  The minor and patch _version numbers are also kept incase the
7272  *  super_block handler wishes to interpret them.
7273  */
md_set_array_info(struct mddev * mddev,struct mdu_array_info_s * info)7274 int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info)
7275 {
7276 	if (info->raid_disks == 0) {
7277 		/* just setting version number for superblock loading */
7278 		if (info->major_version < 0 ||
7279 		    info->major_version >= ARRAY_SIZE(super_types) ||
7280 		    super_types[info->major_version].name == NULL) {
7281 			/* maybe try to auto-load a module? */
7282 			pr_warn("md: superblock version %d not known\n",
7283 				info->major_version);
7284 			return -EINVAL;
7285 		}
7286 		mddev->major_version = info->major_version;
7287 		mddev->minor_version = info->minor_version;
7288 		mddev->patch_version = info->patch_version;
7289 		mddev->persistent = !info->not_persistent;
7290 		/* ensure mddev_put doesn't delete this now that there
7291 		 * is some minimal configuration.
7292 		 */
7293 		mddev->ctime         = ktime_get_real_seconds();
7294 		return 0;
7295 	}
7296 	mddev->major_version = MD_MAJOR_VERSION;
7297 	mddev->minor_version = MD_MINOR_VERSION;
7298 	mddev->patch_version = MD_PATCHLEVEL_VERSION;
7299 	mddev->ctime         = ktime_get_real_seconds();
7300 
7301 	mddev->level         = info->level;
7302 	mddev->clevel[0]     = 0;
7303 	mddev->dev_sectors   = 2 * (sector_t)info->size;
7304 	mddev->raid_disks    = info->raid_disks;
7305 	/* don't set md_minor, it is determined by which /dev/md* was
7306 	 * openned
7307 	 */
7308 	if (info->state & (1<<MD_SB_CLEAN))
7309 		mddev->recovery_cp = MaxSector;
7310 	else
7311 		mddev->recovery_cp = 0;
7312 	mddev->persistent    = ! info->not_persistent;
7313 	mddev->external	     = 0;
7314 
7315 	mddev->layout        = info->layout;
7316 	if (mddev->level == 0)
7317 		/* Cannot trust RAID0 layout info here */
7318 		mddev->layout = -1;
7319 	mddev->chunk_sectors = info->chunk_size >> 9;
7320 
7321 	if (mddev->persistent) {
7322 		mddev->max_disks = MD_SB_DISKS;
7323 		mddev->flags = 0;
7324 		mddev->sb_flags = 0;
7325 	}
7326 	set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
7327 
7328 	mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
7329 	mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
7330 	mddev->bitmap_info.offset = 0;
7331 
7332 	mddev->reshape_position = MaxSector;
7333 
7334 	/*
7335 	 * Generate a 128 bit UUID
7336 	 */
7337 	get_random_bytes(mddev->uuid, 16);
7338 
7339 	mddev->new_level = mddev->level;
7340 	mddev->new_chunk_sectors = mddev->chunk_sectors;
7341 	mddev->new_layout = mddev->layout;
7342 	mddev->delta_disks = 0;
7343 	mddev->reshape_backwards = 0;
7344 
7345 	return 0;
7346 }
7347 
md_set_array_sectors(struct mddev * mddev,sector_t array_sectors)7348 void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors)
7349 {
7350 	lockdep_assert_held(&mddev->reconfig_mutex);
7351 
7352 	if (mddev->external_size)
7353 		return;
7354 
7355 	mddev->array_sectors = array_sectors;
7356 }
7357 EXPORT_SYMBOL(md_set_array_sectors);
7358 
update_size(struct mddev * mddev,sector_t num_sectors)7359 static int update_size(struct mddev *mddev, sector_t num_sectors)
7360 {
7361 	struct md_rdev *rdev;
7362 	int rv;
7363 	int fit = (num_sectors == 0);
7364 	sector_t old_dev_sectors = mddev->dev_sectors;
7365 
7366 	if (mddev->pers->resize == NULL)
7367 		return -EINVAL;
7368 	/* The "num_sectors" is the number of sectors of each device that
7369 	 * is used.  This can only make sense for arrays with redundancy.
7370 	 * linear and raid0 always use whatever space is available. We can only
7371 	 * consider changing this number if no resync or reconstruction is
7372 	 * happening, and if the new size is acceptable. It must fit before the
7373 	 * sb_start or, if that is <data_offset, it must fit before the size
7374 	 * of each device.  If num_sectors is zero, we find the largest size
7375 	 * that fits.
7376 	 */
7377 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
7378 		return -EBUSY;
7379 	if (!md_is_rdwr(mddev))
7380 		return -EROFS;
7381 
7382 	rdev_for_each(rdev, mddev) {
7383 		sector_t avail = rdev->sectors;
7384 
7385 		if (fit && (num_sectors == 0 || num_sectors > avail))
7386 			num_sectors = avail;
7387 		if (avail < num_sectors)
7388 			return -ENOSPC;
7389 	}
7390 	rv = mddev->pers->resize(mddev, num_sectors);
7391 	if (!rv) {
7392 		if (mddev_is_clustered(mddev))
7393 			mddev->cluster_ops->update_size(mddev, old_dev_sectors);
7394 		else if (!mddev_is_dm(mddev))
7395 			set_capacity_and_notify(mddev->gendisk,
7396 						mddev->array_sectors);
7397 	}
7398 	return rv;
7399 }
7400 
update_raid_disks(struct mddev * mddev,int raid_disks)7401 static int update_raid_disks(struct mddev *mddev, int raid_disks)
7402 {
7403 	int rv;
7404 	struct md_rdev *rdev;
7405 	/* change the number of raid disks */
7406 	if (mddev->pers->check_reshape == NULL)
7407 		return -EINVAL;
7408 	if (!md_is_rdwr(mddev))
7409 		return -EROFS;
7410 	if (raid_disks <= 0 ||
7411 	    (mddev->max_disks && raid_disks >= mddev->max_disks))
7412 		return -EINVAL;
7413 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
7414 	    test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) ||
7415 	    mddev->reshape_position != MaxSector)
7416 		return -EBUSY;
7417 
7418 	rdev_for_each(rdev, mddev) {
7419 		if (mddev->raid_disks < raid_disks &&
7420 		    rdev->data_offset < rdev->new_data_offset)
7421 			return -EINVAL;
7422 		if (mddev->raid_disks > raid_disks &&
7423 		    rdev->data_offset > rdev->new_data_offset)
7424 			return -EINVAL;
7425 	}
7426 
7427 	mddev->delta_disks = raid_disks - mddev->raid_disks;
7428 	if (mddev->delta_disks < 0)
7429 		mddev->reshape_backwards = 1;
7430 	else if (mddev->delta_disks > 0)
7431 		mddev->reshape_backwards = 0;
7432 
7433 	rv = mddev->pers->check_reshape(mddev);
7434 	if (rv < 0) {
7435 		mddev->delta_disks = 0;
7436 		mddev->reshape_backwards = 0;
7437 	}
7438 	return rv;
7439 }
7440 
get_cluster_ops(struct mddev * mddev)7441 static int get_cluster_ops(struct mddev *mddev)
7442 {
7443 	xa_lock(&md_submodule);
7444 	mddev->cluster_ops = xa_load(&md_submodule, ID_CLUSTER);
7445 	if (mddev->cluster_ops &&
7446 	    !try_module_get(mddev->cluster_ops->head.owner))
7447 		mddev->cluster_ops = NULL;
7448 	xa_unlock(&md_submodule);
7449 
7450 	return mddev->cluster_ops == NULL ? -ENOENT : 0;
7451 }
7452 
put_cluster_ops(struct mddev * mddev)7453 static void put_cluster_ops(struct mddev *mddev)
7454 {
7455 	if (!mddev->cluster_ops)
7456 		return;
7457 
7458 	mddev->cluster_ops->leave(mddev);
7459 	module_put(mddev->cluster_ops->head.owner);
7460 	mddev->cluster_ops = NULL;
7461 }
7462 
7463 /*
7464  * update_array_info is used to change the configuration of an
7465  * on-line array.
7466  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
7467  * fields in the info are checked against the array.
7468  * Any differences that cannot be handled will cause an error.
7469  * Normally, only one change can be managed at a time.
7470  */
update_array_info(struct mddev * mddev,mdu_array_info_t * info)7471 static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
7472 {
7473 	int rv = 0;
7474 	int cnt = 0;
7475 	int state = 0;
7476 
7477 	/* calculate expected state,ignoring low bits */
7478 	if (mddev->bitmap && mddev->bitmap_info.offset)
7479 		state |= (1 << MD_SB_BITMAP_PRESENT);
7480 
7481 	if (mddev->major_version != info->major_version ||
7482 	    mddev->minor_version != info->minor_version ||
7483 /*	    mddev->patch_version != info->patch_version || */
7484 	    mddev->ctime         != info->ctime         ||
7485 	    mddev->level         != info->level         ||
7486 /*	    mddev->layout        != info->layout        || */
7487 	    mddev->persistent	 != !info->not_persistent ||
7488 	    mddev->chunk_sectors != info->chunk_size >> 9 ||
7489 	    /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
7490 	    ((state^info->state) & 0xfffffe00)
7491 		)
7492 		return -EINVAL;
7493 	/* Check there is only one change */
7494 	if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
7495 		cnt++;
7496 	if (mddev->raid_disks != info->raid_disks)
7497 		cnt++;
7498 	if (mddev->layout != info->layout)
7499 		cnt++;
7500 	if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT))
7501 		cnt++;
7502 	if (cnt == 0)
7503 		return 0;
7504 	if (cnt > 1)
7505 		return -EINVAL;
7506 
7507 	if (mddev->layout != info->layout) {
7508 		/* Change layout
7509 		 * we don't need to do anything at the md level, the
7510 		 * personality will take care of it all.
7511 		 */
7512 		if (mddev->pers->check_reshape == NULL)
7513 			return -EINVAL;
7514 		else {
7515 			mddev->new_layout = info->layout;
7516 			rv = mddev->pers->check_reshape(mddev);
7517 			if (rv)
7518 				mddev->new_layout = mddev->layout;
7519 			return rv;
7520 		}
7521 	}
7522 	if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
7523 		rv = update_size(mddev, (sector_t)info->size * 2);
7524 
7525 	if (mddev->raid_disks    != info->raid_disks)
7526 		rv = update_raid_disks(mddev, info->raid_disks);
7527 
7528 	if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
7529 		if (mddev->pers->quiesce == NULL || mddev->thread == NULL) {
7530 			rv = -EINVAL;
7531 			goto err;
7532 		}
7533 		if (mddev->recovery || mddev->sync_thread) {
7534 			rv = -EBUSY;
7535 			goto err;
7536 		}
7537 		if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
7538 			/* add the bitmap */
7539 			if (mddev->bitmap) {
7540 				rv = -EEXIST;
7541 				goto err;
7542 			}
7543 			if (mddev->bitmap_info.default_offset == 0) {
7544 				rv = -EINVAL;
7545 				goto err;
7546 			}
7547 			mddev->bitmap_info.offset =
7548 				mddev->bitmap_info.default_offset;
7549 			mddev->bitmap_info.space =
7550 				mddev->bitmap_info.default_space;
7551 			rv = mddev->bitmap_ops->create(mddev, -1);
7552 			if (!rv)
7553 				rv = mddev->bitmap_ops->load(mddev);
7554 
7555 			if (rv)
7556 				mddev->bitmap_ops->destroy(mddev);
7557 		} else {
7558 			struct md_bitmap_stats stats;
7559 
7560 			rv = mddev->bitmap_ops->get_stats(mddev->bitmap, &stats);
7561 			if (rv)
7562 				goto err;
7563 
7564 			if (stats.file) {
7565 				rv = -EINVAL;
7566 				goto err;
7567 			}
7568 
7569 			if (mddev->bitmap_info.nodes) {
7570 				/* hold PW on all the bitmap lock */
7571 				if (mddev->cluster_ops->lock_all_bitmaps(mddev) <= 0) {
7572 					pr_warn("md: can't change bitmap to none since the array is in use by more than one node\n");
7573 					rv = -EPERM;
7574 					mddev->cluster_ops->unlock_all_bitmaps(mddev);
7575 					goto err;
7576 				}
7577 
7578 				mddev->bitmap_info.nodes = 0;
7579 				put_cluster_ops(mddev);
7580 				mddev->safemode_delay = DEFAULT_SAFEMODE_DELAY;
7581 			}
7582 			mddev->bitmap_ops->destroy(mddev);
7583 			mddev->bitmap_info.offset = 0;
7584 		}
7585 	}
7586 	md_update_sb(mddev, 1);
7587 	return rv;
7588 err:
7589 	return rv;
7590 }
7591 
set_disk_faulty(struct mddev * mddev,dev_t dev)7592 static int set_disk_faulty(struct mddev *mddev, dev_t dev)
7593 {
7594 	struct md_rdev *rdev;
7595 	int err = 0;
7596 
7597 	if (mddev->pers == NULL)
7598 		return -ENODEV;
7599 
7600 	rcu_read_lock();
7601 	rdev = md_find_rdev_rcu(mddev, dev);
7602 	if (!rdev)
7603 		err =  -ENODEV;
7604 	else {
7605 		md_error(mddev, rdev);
7606 		if (test_bit(MD_BROKEN, &mddev->flags))
7607 			err = -EBUSY;
7608 	}
7609 	rcu_read_unlock();
7610 	return err;
7611 }
7612 
7613 /*
7614  * We have a problem here : there is no easy way to give a CHS
7615  * virtual geometry. We currently pretend that we have a 2 heads
7616  * 4 sectors (with a BIG number of cylinders...). This drives
7617  * dosfs just mad... ;-)
7618  */
md_getgeo(struct block_device * bdev,struct hd_geometry * geo)7619 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
7620 {
7621 	struct mddev *mddev = bdev->bd_disk->private_data;
7622 
7623 	geo->heads = 2;
7624 	geo->sectors = 4;
7625 	geo->cylinders = mddev->array_sectors / 8;
7626 	return 0;
7627 }
7628 
md_ioctl_valid(unsigned int cmd)7629 static inline int md_ioctl_valid(unsigned int cmd)
7630 {
7631 	switch (cmd) {
7632 	case GET_ARRAY_INFO:
7633 	case GET_DISK_INFO:
7634 	case RAID_VERSION:
7635 		return 0;
7636 	case ADD_NEW_DISK:
7637 	case GET_BITMAP_FILE:
7638 	case HOT_ADD_DISK:
7639 	case HOT_REMOVE_DISK:
7640 	case RESTART_ARRAY_RW:
7641 	case RUN_ARRAY:
7642 	case SET_ARRAY_INFO:
7643 	case SET_BITMAP_FILE:
7644 	case SET_DISK_FAULTY:
7645 	case STOP_ARRAY:
7646 	case STOP_ARRAY_RO:
7647 	case CLUSTERED_DISK_NACK:
7648 		if (!capable(CAP_SYS_ADMIN))
7649 			return -EACCES;
7650 		return 0;
7651 	default:
7652 		return -ENOTTY;
7653 	}
7654 }
7655 
md_ioctl_need_suspend(unsigned int cmd)7656 static bool md_ioctl_need_suspend(unsigned int cmd)
7657 {
7658 	switch (cmd) {
7659 	case ADD_NEW_DISK:
7660 	case HOT_ADD_DISK:
7661 	case HOT_REMOVE_DISK:
7662 	case SET_BITMAP_FILE:
7663 	case SET_ARRAY_INFO:
7664 		return true;
7665 	default:
7666 		return false;
7667 	}
7668 }
7669 
__md_set_array_info(struct mddev * mddev,void __user * argp)7670 static int __md_set_array_info(struct mddev *mddev, void __user *argp)
7671 {
7672 	mdu_array_info_t info;
7673 	int err;
7674 
7675 	if (!argp)
7676 		memset(&info, 0, sizeof(info));
7677 	else if (copy_from_user(&info, argp, sizeof(info)))
7678 		return -EFAULT;
7679 
7680 	if (mddev->pers) {
7681 		err = update_array_info(mddev, &info);
7682 		if (err)
7683 			pr_warn("md: couldn't update array info. %d\n", err);
7684 		return err;
7685 	}
7686 
7687 	if (!list_empty(&mddev->disks)) {
7688 		pr_warn("md: array %s already has disks!\n", mdname(mddev));
7689 		return -EBUSY;
7690 	}
7691 
7692 	if (mddev->raid_disks) {
7693 		pr_warn("md: array %s already initialised!\n", mdname(mddev));
7694 		return -EBUSY;
7695 	}
7696 
7697 	err = md_set_array_info(mddev, &info);
7698 	if (err)
7699 		pr_warn("md: couldn't set array info. %d\n", err);
7700 
7701 	return err;
7702 }
7703 
md_ioctl(struct block_device * bdev,blk_mode_t mode,unsigned int cmd,unsigned long arg)7704 static int md_ioctl(struct block_device *bdev, blk_mode_t mode,
7705 			unsigned int cmd, unsigned long arg)
7706 {
7707 	int err = 0;
7708 	void __user *argp = (void __user *)arg;
7709 	struct mddev *mddev = NULL;
7710 
7711 	err = md_ioctl_valid(cmd);
7712 	if (err)
7713 		return err;
7714 
7715 	/*
7716 	 * Commands dealing with the RAID driver but not any
7717 	 * particular array:
7718 	 */
7719 	if (cmd == RAID_VERSION)
7720 		return get_version(argp);
7721 
7722 	/*
7723 	 * Commands creating/starting a new array:
7724 	 */
7725 
7726 	mddev = bdev->bd_disk->private_data;
7727 
7728 	/* Some actions do not requires the mutex */
7729 	switch (cmd) {
7730 	case GET_ARRAY_INFO:
7731 		if (!mddev->raid_disks && !mddev->external)
7732 			return -ENODEV;
7733 		return get_array_info(mddev, argp);
7734 
7735 	case GET_DISK_INFO:
7736 		if (!mddev->raid_disks && !mddev->external)
7737 			return -ENODEV;
7738 		return get_disk_info(mddev, argp);
7739 
7740 	case SET_DISK_FAULTY:
7741 		return set_disk_faulty(mddev, new_decode_dev(arg));
7742 
7743 	case GET_BITMAP_FILE:
7744 		return get_bitmap_file(mddev, argp);
7745 	}
7746 
7747 	if (cmd == STOP_ARRAY || cmd == STOP_ARRAY_RO) {
7748 		/* Need to flush page cache, and ensure no-one else opens
7749 		 * and writes
7750 		 */
7751 		err = mddev_set_closing_and_sync_blockdev(mddev, 1);
7752 		if (err)
7753 			return err;
7754 	}
7755 
7756 	if (!md_is_rdwr(mddev))
7757 		flush_work(&mddev->sync_work);
7758 
7759 	err = md_ioctl_need_suspend(cmd) ? mddev_suspend_and_lock(mddev) :
7760 					   mddev_lock(mddev);
7761 	if (err) {
7762 		pr_debug("md: ioctl lock interrupted, reason %d, cmd %d\n",
7763 			 err, cmd);
7764 		goto out;
7765 	}
7766 
7767 	if (cmd == SET_ARRAY_INFO) {
7768 		err = __md_set_array_info(mddev, argp);
7769 		goto unlock;
7770 	}
7771 
7772 	/*
7773 	 * Commands querying/configuring an existing array:
7774 	 */
7775 	/* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
7776 	 * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
7777 	if ((!mddev->raid_disks && !mddev->external)
7778 	    && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
7779 	    && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
7780 	    && cmd != GET_BITMAP_FILE) {
7781 		err = -ENODEV;
7782 		goto unlock;
7783 	}
7784 
7785 	/*
7786 	 * Commands even a read-only array can execute:
7787 	 */
7788 	switch (cmd) {
7789 	case RESTART_ARRAY_RW:
7790 		err = restart_array(mddev);
7791 		goto unlock;
7792 
7793 	case STOP_ARRAY:
7794 		err = do_md_stop(mddev, 0);
7795 		goto unlock;
7796 
7797 	case STOP_ARRAY_RO:
7798 		if (mddev->pers)
7799 			err = md_set_readonly(mddev);
7800 		goto unlock;
7801 
7802 	case HOT_REMOVE_DISK:
7803 		err = hot_remove_disk(mddev, new_decode_dev(arg));
7804 		goto unlock;
7805 
7806 	case ADD_NEW_DISK:
7807 		/* We can support ADD_NEW_DISK on read-only arrays
7808 		 * only if we are re-adding a preexisting device.
7809 		 * So require mddev->pers and MD_DISK_SYNC.
7810 		 */
7811 		if (mddev->pers) {
7812 			mdu_disk_info_t info;
7813 			if (copy_from_user(&info, argp, sizeof(info)))
7814 				err = -EFAULT;
7815 			else if (!(info.state & (1<<MD_DISK_SYNC)))
7816 				/* Need to clear read-only for this */
7817 				break;
7818 			else
7819 				err = md_add_new_disk(mddev, &info);
7820 			goto unlock;
7821 		}
7822 		break;
7823 	}
7824 
7825 	/*
7826 	 * The remaining ioctls are changing the state of the
7827 	 * superblock, so we do not allow them on read-only arrays.
7828 	 */
7829 	if (!md_is_rdwr(mddev) && mddev->pers) {
7830 		if (mddev->ro != MD_AUTO_READ) {
7831 			err = -EROFS;
7832 			goto unlock;
7833 		}
7834 		mddev->ro = MD_RDWR;
7835 		sysfs_notify_dirent_safe(mddev->sysfs_state);
7836 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7837 		/* mddev_unlock will wake thread */
7838 		/* If a device failed while we were read-only, we
7839 		 * need to make sure the metadata is updated now.
7840 		 */
7841 		if (test_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags)) {
7842 			mddev_unlock(mddev);
7843 			wait_event(mddev->sb_wait,
7844 				   !test_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags) &&
7845 				   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
7846 			mddev_lock_nointr(mddev);
7847 		}
7848 	}
7849 
7850 	switch (cmd) {
7851 	case ADD_NEW_DISK:
7852 	{
7853 		mdu_disk_info_t info;
7854 		if (copy_from_user(&info, argp, sizeof(info)))
7855 			err = -EFAULT;
7856 		else
7857 			err = md_add_new_disk(mddev, &info);
7858 		goto unlock;
7859 	}
7860 
7861 	case CLUSTERED_DISK_NACK:
7862 		if (mddev_is_clustered(mddev))
7863 			mddev->cluster_ops->new_disk_ack(mddev, false);
7864 		else
7865 			err = -EINVAL;
7866 		goto unlock;
7867 
7868 	case HOT_ADD_DISK:
7869 		err = hot_add_disk(mddev, new_decode_dev(arg));
7870 		goto unlock;
7871 
7872 	case RUN_ARRAY:
7873 		err = do_md_run(mddev);
7874 		goto unlock;
7875 
7876 	case SET_BITMAP_FILE:
7877 		err = set_bitmap_file(mddev, (int)arg);
7878 		goto unlock;
7879 
7880 	default:
7881 		err = -EINVAL;
7882 		goto unlock;
7883 	}
7884 
7885 unlock:
7886 	if (mddev->hold_active == UNTIL_IOCTL &&
7887 	    err != -EINVAL)
7888 		mddev->hold_active = 0;
7889 
7890 	md_ioctl_need_suspend(cmd) ? mddev_unlock_and_resume(mddev) :
7891 				     mddev_unlock(mddev);
7892 
7893 out:
7894 	if (cmd == STOP_ARRAY_RO || (err && cmd == STOP_ARRAY))
7895 		clear_bit(MD_CLOSING, &mddev->flags);
7896 	return err;
7897 }
7898 #ifdef CONFIG_COMPAT
md_compat_ioctl(struct block_device * bdev,blk_mode_t mode,unsigned int cmd,unsigned long arg)7899 static int md_compat_ioctl(struct block_device *bdev, blk_mode_t mode,
7900 		    unsigned int cmd, unsigned long arg)
7901 {
7902 	switch (cmd) {
7903 	case HOT_REMOVE_DISK:
7904 	case HOT_ADD_DISK:
7905 	case SET_DISK_FAULTY:
7906 	case SET_BITMAP_FILE:
7907 		/* These take in integer arg, do not convert */
7908 		break;
7909 	default:
7910 		arg = (unsigned long)compat_ptr(arg);
7911 		break;
7912 	}
7913 
7914 	return md_ioctl(bdev, mode, cmd, arg);
7915 }
7916 #endif /* CONFIG_COMPAT */
7917 
md_set_read_only(struct block_device * bdev,bool ro)7918 static int md_set_read_only(struct block_device *bdev, bool ro)
7919 {
7920 	struct mddev *mddev = bdev->bd_disk->private_data;
7921 	int err;
7922 
7923 	err = mddev_lock(mddev);
7924 	if (err)
7925 		return err;
7926 
7927 	if (!mddev->raid_disks && !mddev->external) {
7928 		err = -ENODEV;
7929 		goto out_unlock;
7930 	}
7931 
7932 	/*
7933 	 * Transitioning to read-auto need only happen for arrays that call
7934 	 * md_write_start and which are not ready for writes yet.
7935 	 */
7936 	if (!ro && mddev->ro == MD_RDONLY && mddev->pers) {
7937 		err = restart_array(mddev);
7938 		if (err)
7939 			goto out_unlock;
7940 		mddev->ro = MD_AUTO_READ;
7941 	}
7942 
7943 out_unlock:
7944 	mddev_unlock(mddev);
7945 	return err;
7946 }
7947 
md_open(struct gendisk * disk,blk_mode_t mode)7948 static int md_open(struct gendisk *disk, blk_mode_t mode)
7949 {
7950 	struct mddev *mddev;
7951 	int err;
7952 
7953 	spin_lock(&all_mddevs_lock);
7954 	mddev = mddev_get(disk->private_data);
7955 	spin_unlock(&all_mddevs_lock);
7956 	if (!mddev)
7957 		return -ENODEV;
7958 
7959 	err = mutex_lock_interruptible(&mddev->open_mutex);
7960 	if (err)
7961 		goto out;
7962 
7963 	err = -ENODEV;
7964 	if (test_bit(MD_CLOSING, &mddev->flags))
7965 		goto out_unlock;
7966 
7967 	atomic_inc(&mddev->openers);
7968 	mutex_unlock(&mddev->open_mutex);
7969 
7970 	disk_check_media_change(disk);
7971 	return 0;
7972 
7973 out_unlock:
7974 	mutex_unlock(&mddev->open_mutex);
7975 out:
7976 	mddev_put(mddev);
7977 	return err;
7978 }
7979 
md_release(struct gendisk * disk)7980 static void md_release(struct gendisk *disk)
7981 {
7982 	struct mddev *mddev = disk->private_data;
7983 
7984 	BUG_ON(!mddev);
7985 	atomic_dec(&mddev->openers);
7986 	mddev_put(mddev);
7987 }
7988 
md_check_events(struct gendisk * disk,unsigned int clearing)7989 static unsigned int md_check_events(struct gendisk *disk, unsigned int clearing)
7990 {
7991 	struct mddev *mddev = disk->private_data;
7992 	unsigned int ret = 0;
7993 
7994 	if (mddev->changed)
7995 		ret = DISK_EVENT_MEDIA_CHANGE;
7996 	mddev->changed = 0;
7997 	return ret;
7998 }
7999 
md_free_disk(struct gendisk * disk)8000 static void md_free_disk(struct gendisk *disk)
8001 {
8002 	struct mddev *mddev = disk->private_data;
8003 
8004 	mddev_free(mddev);
8005 }
8006 
8007 const struct block_device_operations md_fops =
8008 {
8009 	.owner		= THIS_MODULE,
8010 	.submit_bio	= md_submit_bio,
8011 	.open		= md_open,
8012 	.release	= md_release,
8013 	.ioctl		= md_ioctl,
8014 #ifdef CONFIG_COMPAT
8015 	.compat_ioctl	= md_compat_ioctl,
8016 #endif
8017 	.getgeo		= md_getgeo,
8018 	.check_events	= md_check_events,
8019 	.set_read_only	= md_set_read_only,
8020 	.free_disk	= md_free_disk,
8021 };
8022 
md_thread(void * arg)8023 static int md_thread(void *arg)
8024 {
8025 	struct md_thread *thread = arg;
8026 
8027 	/*
8028 	 * md_thread is a 'system-thread', it's priority should be very
8029 	 * high. We avoid resource deadlocks individually in each
8030 	 * raid personality. (RAID5 does preallocation) We also use RR and
8031 	 * the very same RT priority as kswapd, thus we will never get
8032 	 * into a priority inversion deadlock.
8033 	 *
8034 	 * we definitely have to have equal or higher priority than
8035 	 * bdflush, otherwise bdflush will deadlock if there are too
8036 	 * many dirty RAID5 blocks.
8037 	 */
8038 
8039 	allow_signal(SIGKILL);
8040 	while (!kthread_should_stop()) {
8041 
8042 		/* We need to wait INTERRUPTIBLE so that
8043 		 * we don't add to the load-average.
8044 		 * That means we need to be sure no signals are
8045 		 * pending
8046 		 */
8047 		if (signal_pending(current))
8048 			flush_signals(current);
8049 
8050 		wait_event_interruptible_timeout
8051 			(thread->wqueue,
8052 			 test_bit(THREAD_WAKEUP, &thread->flags)
8053 			 || kthread_should_stop() || kthread_should_park(),
8054 			 thread->timeout);
8055 
8056 		clear_bit(THREAD_WAKEUP, &thread->flags);
8057 		if (kthread_should_park())
8058 			kthread_parkme();
8059 		if (!kthread_should_stop())
8060 			thread->run(thread);
8061 	}
8062 
8063 	return 0;
8064 }
8065 
md_wakeup_thread_directly(struct md_thread __rcu * thread)8066 static void md_wakeup_thread_directly(struct md_thread __rcu *thread)
8067 {
8068 	struct md_thread *t;
8069 
8070 	rcu_read_lock();
8071 	t = rcu_dereference(thread);
8072 	if (t)
8073 		wake_up_process(t->tsk);
8074 	rcu_read_unlock();
8075 }
8076 
md_wakeup_thread(struct md_thread __rcu * thread)8077 void md_wakeup_thread(struct md_thread __rcu *thread)
8078 {
8079 	struct md_thread *t;
8080 
8081 	rcu_read_lock();
8082 	t = rcu_dereference(thread);
8083 	if (t) {
8084 		pr_debug("md: waking up MD thread %s.\n", t->tsk->comm);
8085 		set_bit(THREAD_WAKEUP, &t->flags);
8086 		if (wq_has_sleeper(&t->wqueue))
8087 			wake_up(&t->wqueue);
8088 	}
8089 	rcu_read_unlock();
8090 }
8091 EXPORT_SYMBOL(md_wakeup_thread);
8092 
md_register_thread(void (* run)(struct md_thread *),struct mddev * mddev,const char * name)8093 struct md_thread *md_register_thread(void (*run) (struct md_thread *),
8094 		struct mddev *mddev, const char *name)
8095 {
8096 	struct md_thread *thread;
8097 
8098 	thread = kzalloc(sizeof(struct md_thread), GFP_KERNEL);
8099 	if (!thread)
8100 		return NULL;
8101 
8102 	init_waitqueue_head(&thread->wqueue);
8103 
8104 	thread->run = run;
8105 	thread->mddev = mddev;
8106 	thread->timeout = MAX_SCHEDULE_TIMEOUT;
8107 	thread->tsk = kthread_run(md_thread, thread,
8108 				  "%s_%s",
8109 				  mdname(thread->mddev),
8110 				  name);
8111 	if (IS_ERR(thread->tsk)) {
8112 		kfree(thread);
8113 		return NULL;
8114 	}
8115 	return thread;
8116 }
8117 EXPORT_SYMBOL(md_register_thread);
8118 
md_unregister_thread(struct mddev * mddev,struct md_thread __rcu ** threadp)8119 void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp)
8120 {
8121 	struct md_thread *thread = rcu_dereference_protected(*threadp,
8122 					lockdep_is_held(&mddev->reconfig_mutex));
8123 
8124 	if (!thread)
8125 		return;
8126 
8127 	rcu_assign_pointer(*threadp, NULL);
8128 	synchronize_rcu();
8129 
8130 	pr_debug("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
8131 	kthread_stop(thread->tsk);
8132 	kfree(thread);
8133 }
8134 EXPORT_SYMBOL(md_unregister_thread);
8135 
md_error(struct mddev * mddev,struct md_rdev * rdev)8136 void md_error(struct mddev *mddev, struct md_rdev *rdev)
8137 {
8138 	if (!rdev || test_bit(Faulty, &rdev->flags))
8139 		return;
8140 
8141 	if (!mddev->pers || !mddev->pers->error_handler)
8142 		return;
8143 	mddev->pers->error_handler(mddev, rdev);
8144 
8145 	if (mddev->pers->head.id == ID_RAID0 ||
8146 	    mddev->pers->head.id == ID_LINEAR)
8147 		return;
8148 
8149 	if (mddev->degraded && !test_bit(MD_BROKEN, &mddev->flags))
8150 		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
8151 	sysfs_notify_dirent_safe(rdev->sysfs_state);
8152 	set_bit(MD_RECOVERY_INTR, &mddev->recovery);
8153 	if (!test_bit(MD_BROKEN, &mddev->flags)) {
8154 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
8155 		md_wakeup_thread(mddev->thread);
8156 	}
8157 	if (mddev->event_work.func)
8158 		queue_work(md_misc_wq, &mddev->event_work);
8159 	md_new_event();
8160 }
8161 EXPORT_SYMBOL(md_error);
8162 
8163 /* seq_file implementation /proc/mdstat */
8164 
status_unused(struct seq_file * seq)8165 static void status_unused(struct seq_file *seq)
8166 {
8167 	int i = 0;
8168 	struct md_rdev *rdev;
8169 
8170 	seq_printf(seq, "unused devices: ");
8171 
8172 	list_for_each_entry(rdev, &pending_raid_disks, same_set) {
8173 		i++;
8174 		seq_printf(seq, "%pg ", rdev->bdev);
8175 	}
8176 	if (!i)
8177 		seq_printf(seq, "<none>");
8178 
8179 	seq_printf(seq, "\n");
8180 }
8181 
status_personalities(struct seq_file * seq)8182 static void status_personalities(struct seq_file *seq)
8183 {
8184 	struct md_submodule_head *head;
8185 	unsigned long i;
8186 
8187 	seq_puts(seq, "Personalities : ");
8188 
8189 	xa_lock(&md_submodule);
8190 	xa_for_each(&md_submodule, i, head)
8191 		if (head->type == MD_PERSONALITY)
8192 			seq_printf(seq, "[%s] ", head->name);
8193 	xa_unlock(&md_submodule);
8194 
8195 	seq_puts(seq, "\n");
8196 }
8197 
status_resync(struct seq_file * seq,struct mddev * mddev)8198 static int status_resync(struct seq_file *seq, struct mddev *mddev)
8199 {
8200 	sector_t max_sectors, resync, res;
8201 	unsigned long dt, db = 0;
8202 	sector_t rt, curr_mark_cnt, resync_mark_cnt;
8203 	int scale, recovery_active;
8204 	unsigned int per_milli;
8205 
8206 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
8207 	    test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
8208 		max_sectors = mddev->resync_max_sectors;
8209 	else
8210 		max_sectors = mddev->dev_sectors;
8211 
8212 	resync = mddev->curr_resync;
8213 	if (resync < MD_RESYNC_ACTIVE) {
8214 		if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
8215 			/* Still cleaning up */
8216 			resync = max_sectors;
8217 	} else if (resync > max_sectors) {
8218 		resync = max_sectors;
8219 	} else {
8220 		res = atomic_read(&mddev->recovery_active);
8221 		/*
8222 		 * Resync has started, but the subtraction has overflowed or
8223 		 * yielded one of the special values. Force it to active to
8224 		 * ensure the status reports an active resync.
8225 		 */
8226 		if (resync < res || resync - res < MD_RESYNC_ACTIVE)
8227 			resync = MD_RESYNC_ACTIVE;
8228 		else
8229 			resync -= res;
8230 	}
8231 
8232 	if (resync == MD_RESYNC_NONE) {
8233 		if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery)) {
8234 			struct md_rdev *rdev;
8235 
8236 			rdev_for_each(rdev, mddev)
8237 				if (rdev->raid_disk >= 0 &&
8238 				    !test_bit(Faulty, &rdev->flags) &&
8239 				    rdev->recovery_offset != MaxSector &&
8240 				    rdev->recovery_offset) {
8241 					seq_printf(seq, "\trecover=REMOTE");
8242 					return 1;
8243 				}
8244 			if (mddev->reshape_position != MaxSector)
8245 				seq_printf(seq, "\treshape=REMOTE");
8246 			else
8247 				seq_printf(seq, "\tresync=REMOTE");
8248 			return 1;
8249 		}
8250 		if (mddev->recovery_cp < MaxSector) {
8251 			seq_printf(seq, "\tresync=PENDING");
8252 			return 1;
8253 		}
8254 		return 0;
8255 	}
8256 	if (resync < MD_RESYNC_ACTIVE) {
8257 		seq_printf(seq, "\tresync=DELAYED");
8258 		return 1;
8259 	}
8260 
8261 	WARN_ON(max_sectors == 0);
8262 	/* Pick 'scale' such that (resync>>scale)*1000 will fit
8263 	 * in a sector_t, and (max_sectors>>scale) will fit in a
8264 	 * u32, as those are the requirements for sector_div.
8265 	 * Thus 'scale' must be at least 10
8266 	 */
8267 	scale = 10;
8268 	if (sizeof(sector_t) > sizeof(unsigned long)) {
8269 		while ( max_sectors/2 > (1ULL<<(scale+32)))
8270 			scale++;
8271 	}
8272 	res = (resync>>scale)*1000;
8273 	sector_div(res, (u32)((max_sectors>>scale)+1));
8274 
8275 	per_milli = res;
8276 	{
8277 		int i, x = per_milli/50, y = 20-x;
8278 		seq_printf(seq, "[");
8279 		for (i = 0; i < x; i++)
8280 			seq_printf(seq, "=");
8281 		seq_printf(seq, ">");
8282 		for (i = 0; i < y; i++)
8283 			seq_printf(seq, ".");
8284 		seq_printf(seq, "] ");
8285 	}
8286 	seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
8287 		   (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
8288 		    "reshape" :
8289 		    (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
8290 		     "check" :
8291 		     (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
8292 		      "resync" : "recovery"))),
8293 		   per_milli/10, per_milli % 10,
8294 		   (unsigned long long) resync/2,
8295 		   (unsigned long long) max_sectors/2);
8296 
8297 	/*
8298 	 * dt: time from mark until now
8299 	 * db: blocks written from mark until now
8300 	 * rt: remaining time
8301 	 *
8302 	 * rt is a sector_t, which is always 64bit now. We are keeping
8303 	 * the original algorithm, but it is not really necessary.
8304 	 *
8305 	 * Original algorithm:
8306 	 *   So we divide before multiply in case it is 32bit and close
8307 	 *   to the limit.
8308 	 *   We scale the divisor (db) by 32 to avoid losing precision
8309 	 *   near the end of resync when the number of remaining sectors
8310 	 *   is close to 'db'.
8311 	 *   We then divide rt by 32 after multiplying by db to compensate.
8312 	 *   The '+1' avoids division by zero if db is very small.
8313 	 */
8314 	dt = ((jiffies - mddev->resync_mark) / HZ);
8315 	if (!dt) dt++;
8316 
8317 	curr_mark_cnt = mddev->curr_mark_cnt;
8318 	recovery_active = atomic_read(&mddev->recovery_active);
8319 	resync_mark_cnt = mddev->resync_mark_cnt;
8320 
8321 	if (curr_mark_cnt >= (recovery_active + resync_mark_cnt))
8322 		db = curr_mark_cnt - (recovery_active + resync_mark_cnt);
8323 
8324 	rt = max_sectors - resync;    /* number of remaining sectors */
8325 	rt = div64_u64(rt, db/32+1);
8326 	rt *= dt;
8327 	rt >>= 5;
8328 
8329 	seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60,
8330 		   ((unsigned long)rt % 60)/6);
8331 
8332 	seq_printf(seq, " speed=%ldK/sec", db/2/dt);
8333 	return 1;
8334 }
8335 
md_seq_start(struct seq_file * seq,loff_t * pos)8336 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
8337 	__acquires(&all_mddevs_lock)
8338 {
8339 	seq->poll_event = atomic_read(&md_event_count);
8340 	spin_lock(&all_mddevs_lock);
8341 
8342 	return seq_list_start_head(&all_mddevs, *pos);
8343 }
8344 
md_seq_next(struct seq_file * seq,void * v,loff_t * pos)8345 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
8346 {
8347 	return seq_list_next(v, &all_mddevs, pos);
8348 }
8349 
md_seq_stop(struct seq_file * seq,void * v)8350 static void md_seq_stop(struct seq_file *seq, void *v)
8351 	__releases(&all_mddevs_lock)
8352 {
8353 	spin_unlock(&all_mddevs_lock);
8354 }
8355 
md_bitmap_status(struct seq_file * seq,struct mddev * mddev)8356 static void md_bitmap_status(struct seq_file *seq, struct mddev *mddev)
8357 {
8358 	struct md_bitmap_stats stats;
8359 	unsigned long used_pages;
8360 	unsigned long chunk_kb;
8361 	int err;
8362 
8363 	err = mddev->bitmap_ops->get_stats(mddev->bitmap, &stats);
8364 	if (err)
8365 		return;
8366 
8367 	chunk_kb = mddev->bitmap_info.chunksize >> 10;
8368 	used_pages = stats.pages - stats.missing_pages;
8369 
8370 	seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], %lu%s chunk",
8371 		   used_pages, stats.pages, used_pages << (PAGE_SHIFT - 10),
8372 		   chunk_kb ? chunk_kb : mddev->bitmap_info.chunksize,
8373 		   chunk_kb ? "KB" : "B");
8374 
8375 	if (stats.file) {
8376 		seq_puts(seq, ", file: ");
8377 		seq_file_path(seq, stats.file, " \t\n");
8378 	}
8379 
8380 	seq_putc(seq, '\n');
8381 }
8382 
md_seq_show(struct seq_file * seq,void * v)8383 static int md_seq_show(struct seq_file *seq, void *v)
8384 {
8385 	struct mddev *mddev;
8386 	sector_t sectors;
8387 	struct md_rdev *rdev;
8388 
8389 	if (v == &all_mddevs) {
8390 		status_personalities(seq);
8391 		if (list_empty(&all_mddevs))
8392 			status_unused(seq);
8393 		return 0;
8394 	}
8395 
8396 	mddev = list_entry(v, struct mddev, all_mddevs);
8397 	if (!mddev_get(mddev))
8398 		return 0;
8399 
8400 	spin_unlock(&all_mddevs_lock);
8401 
8402 	/* prevent bitmap to be freed after checking */
8403 	mutex_lock(&mddev->bitmap_info.mutex);
8404 
8405 	spin_lock(&mddev->lock);
8406 	if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
8407 		seq_printf(seq, "%s : ", mdname(mddev));
8408 		if (mddev->pers) {
8409 			if (test_bit(MD_BROKEN, &mddev->flags))
8410 				seq_printf(seq, "broken");
8411 			else
8412 				seq_printf(seq, "active");
8413 			if (mddev->ro == MD_RDONLY)
8414 				seq_printf(seq, " (read-only)");
8415 			if (mddev->ro == MD_AUTO_READ)
8416 				seq_printf(seq, " (auto-read-only)");
8417 			seq_printf(seq, " %s", mddev->pers->head.name);
8418 		} else {
8419 			seq_printf(seq, "inactive");
8420 		}
8421 
8422 		sectors = 0;
8423 		rcu_read_lock();
8424 		rdev_for_each_rcu(rdev, mddev) {
8425 			seq_printf(seq, " %pg[%d]", rdev->bdev, rdev->desc_nr);
8426 
8427 			if (test_bit(WriteMostly, &rdev->flags))
8428 				seq_printf(seq, "(W)");
8429 			if (test_bit(Journal, &rdev->flags))
8430 				seq_printf(seq, "(J)");
8431 			if (test_bit(Faulty, &rdev->flags)) {
8432 				seq_printf(seq, "(F)");
8433 				continue;
8434 			}
8435 			if (rdev->raid_disk < 0)
8436 				seq_printf(seq, "(S)"); /* spare */
8437 			if (test_bit(Replacement, &rdev->flags))
8438 				seq_printf(seq, "(R)");
8439 			sectors += rdev->sectors;
8440 		}
8441 		rcu_read_unlock();
8442 
8443 		if (!list_empty(&mddev->disks)) {
8444 			if (mddev->pers)
8445 				seq_printf(seq, "\n      %llu blocks",
8446 					   (unsigned long long)
8447 					   mddev->array_sectors / 2);
8448 			else
8449 				seq_printf(seq, "\n      %llu blocks",
8450 					   (unsigned long long)sectors / 2);
8451 		}
8452 		if (mddev->persistent) {
8453 			if (mddev->major_version != 0 ||
8454 			    mddev->minor_version != 90) {
8455 				seq_printf(seq," super %d.%d",
8456 					   mddev->major_version,
8457 					   mddev->minor_version);
8458 			}
8459 		} else if (mddev->external)
8460 			seq_printf(seq, " super external:%s",
8461 				   mddev->metadata_type);
8462 		else
8463 			seq_printf(seq, " super non-persistent");
8464 
8465 		if (mddev->pers) {
8466 			mddev->pers->status(seq, mddev);
8467 			seq_printf(seq, "\n      ");
8468 			if (mddev->pers->sync_request) {
8469 				if (status_resync(seq, mddev))
8470 					seq_printf(seq, "\n      ");
8471 			}
8472 		} else
8473 			seq_printf(seq, "\n       ");
8474 
8475 		md_bitmap_status(seq, mddev);
8476 
8477 		seq_printf(seq, "\n");
8478 	}
8479 	spin_unlock(&mddev->lock);
8480 	mutex_unlock(&mddev->bitmap_info.mutex);
8481 	spin_lock(&all_mddevs_lock);
8482 
8483 	if (mddev == list_last_entry(&all_mddevs, struct mddev, all_mddevs))
8484 		status_unused(seq);
8485 
8486 	mddev_put_locked(mddev);
8487 	return 0;
8488 }
8489 
8490 static const struct seq_operations md_seq_ops = {
8491 	.start  = md_seq_start,
8492 	.next   = md_seq_next,
8493 	.stop   = md_seq_stop,
8494 	.show   = md_seq_show,
8495 };
8496 
md_seq_open(struct inode * inode,struct file * file)8497 static int md_seq_open(struct inode *inode, struct file *file)
8498 {
8499 	struct seq_file *seq;
8500 	int error;
8501 
8502 	error = seq_open(file, &md_seq_ops);
8503 	if (error)
8504 		return error;
8505 
8506 	seq = file->private_data;
8507 	seq->poll_event = atomic_read(&md_event_count);
8508 	return error;
8509 }
8510 
8511 static int md_unloading;
mdstat_poll(struct file * filp,poll_table * wait)8512 static __poll_t mdstat_poll(struct file *filp, poll_table *wait)
8513 {
8514 	struct seq_file *seq = filp->private_data;
8515 	__poll_t mask;
8516 
8517 	if (md_unloading)
8518 		return EPOLLIN|EPOLLRDNORM|EPOLLERR|EPOLLPRI;
8519 	poll_wait(filp, &md_event_waiters, wait);
8520 
8521 	/* always allow read */
8522 	mask = EPOLLIN | EPOLLRDNORM;
8523 
8524 	if (seq->poll_event != atomic_read(&md_event_count))
8525 		mask |= EPOLLERR | EPOLLPRI;
8526 	return mask;
8527 }
8528 
8529 static const struct proc_ops mdstat_proc_ops = {
8530 	.proc_open	= md_seq_open,
8531 	.proc_read	= seq_read,
8532 	.proc_lseek	= seq_lseek,
8533 	.proc_release	= seq_release,
8534 	.proc_poll	= mdstat_poll,
8535 };
8536 
register_md_submodule(struct md_submodule_head * msh)8537 int register_md_submodule(struct md_submodule_head *msh)
8538 {
8539 	return xa_insert(&md_submodule, msh->id, msh, GFP_KERNEL);
8540 }
8541 EXPORT_SYMBOL_GPL(register_md_submodule);
8542 
unregister_md_submodule(struct md_submodule_head * msh)8543 void unregister_md_submodule(struct md_submodule_head *msh)
8544 {
8545 	xa_erase(&md_submodule, msh->id);
8546 }
8547 EXPORT_SYMBOL_GPL(unregister_md_submodule);
8548 
md_setup_cluster(struct mddev * mddev,int nodes)8549 int md_setup_cluster(struct mddev *mddev, int nodes)
8550 {
8551 	int ret = get_cluster_ops(mddev);
8552 
8553 	if (ret) {
8554 		request_module("md-cluster");
8555 		ret = get_cluster_ops(mddev);
8556 	}
8557 
8558 	/* ensure module won't be unloaded */
8559 	if (ret) {
8560 		pr_warn("can't find md-cluster module or get its reference.\n");
8561 		return ret;
8562 	}
8563 
8564 	ret = mddev->cluster_ops->join(mddev, nodes);
8565 	if (!ret)
8566 		mddev->safemode_delay = 0;
8567 	return ret;
8568 }
8569 
md_cluster_stop(struct mddev * mddev)8570 void md_cluster_stop(struct mddev *mddev)
8571 {
8572 	put_cluster_ops(mddev);
8573 }
8574 
is_mddev_idle(struct mddev * mddev,int init)8575 static int is_mddev_idle(struct mddev *mddev, int init)
8576 {
8577 	struct md_rdev *rdev;
8578 	int idle;
8579 	int curr_events;
8580 
8581 	idle = 1;
8582 	rcu_read_lock();
8583 	rdev_for_each_rcu(rdev, mddev) {
8584 		struct gendisk *disk = rdev->bdev->bd_disk;
8585 
8586 		if (!init && !blk_queue_io_stat(disk->queue))
8587 			continue;
8588 
8589 		curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
8590 			      atomic_read(&disk->sync_io);
8591 		/* sync IO will cause sync_io to increase before the disk_stats
8592 		 * as sync_io is counted when a request starts, and
8593 		 * disk_stats is counted when it completes.
8594 		 * So resync activity will cause curr_events to be smaller than
8595 		 * when there was no such activity.
8596 		 * non-sync IO will cause disk_stat to increase without
8597 		 * increasing sync_io so curr_events will (eventually)
8598 		 * be larger than it was before.  Once it becomes
8599 		 * substantially larger, the test below will cause
8600 		 * the array to appear non-idle, and resync will slow
8601 		 * down.
8602 		 * If there is a lot of outstanding resync activity when
8603 		 * we set last_event to curr_events, then all that activity
8604 		 * completing might cause the array to appear non-idle
8605 		 * and resync will be slowed down even though there might
8606 		 * not have been non-resync activity.  This will only
8607 		 * happen once though.  'last_events' will soon reflect
8608 		 * the state where there is little or no outstanding
8609 		 * resync requests, and further resync activity will
8610 		 * always make curr_events less than last_events.
8611 		 *
8612 		 */
8613 		if (init || curr_events - rdev->last_events > 64) {
8614 			rdev->last_events = curr_events;
8615 			idle = 0;
8616 		}
8617 	}
8618 	rcu_read_unlock();
8619 	return idle;
8620 }
8621 
md_done_sync(struct mddev * mddev,int blocks,int ok)8622 void md_done_sync(struct mddev *mddev, int blocks, int ok)
8623 {
8624 	/* another "blocks" (512byte) blocks have been synced */
8625 	atomic_sub(blocks, &mddev->recovery_active);
8626 	wake_up(&mddev->recovery_wait);
8627 	if (!ok) {
8628 		set_bit(MD_RECOVERY_INTR, &mddev->recovery);
8629 		set_bit(MD_RECOVERY_ERROR, &mddev->recovery);
8630 		md_wakeup_thread(mddev->thread);
8631 		// stop recovery, signal do_sync ....
8632 	}
8633 }
8634 EXPORT_SYMBOL(md_done_sync);
8635 
8636 /* md_write_start(mddev, bi)
8637  * If we need to update some array metadata (e.g. 'active' flag
8638  * in superblock) before writing, schedule a superblock update
8639  * and wait for it to complete.
8640  * A return value of 'false' means that the write wasn't recorded
8641  * and cannot proceed as the array is being suspend.
8642  */
md_write_start(struct mddev * mddev,struct bio * bi)8643 void md_write_start(struct mddev *mddev, struct bio *bi)
8644 {
8645 	int did_change = 0;
8646 
8647 	if (bio_data_dir(bi) != WRITE)
8648 		return;
8649 
8650 	BUG_ON(mddev->ro == MD_RDONLY);
8651 	if (mddev->ro == MD_AUTO_READ) {
8652 		/* need to switch to read/write */
8653 		mddev->ro = MD_RDWR;
8654 		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
8655 		md_wakeup_thread(mddev->thread);
8656 		md_wakeup_thread(mddev->sync_thread);
8657 		did_change = 1;
8658 	}
8659 	rcu_read_lock();
8660 	percpu_ref_get(&mddev->writes_pending);
8661 	smp_mb(); /* Match smp_mb in set_in_sync() */
8662 	if (mddev->safemode == 1)
8663 		mddev->safemode = 0;
8664 	/* sync_checkers is always 0 when writes_pending is in per-cpu mode */
8665 	if (mddev->in_sync || mddev->sync_checkers) {
8666 		spin_lock(&mddev->lock);
8667 		if (mddev->in_sync) {
8668 			mddev->in_sync = 0;
8669 			set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
8670 			set_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
8671 			md_wakeup_thread(mddev->thread);
8672 			did_change = 1;
8673 		}
8674 		spin_unlock(&mddev->lock);
8675 	}
8676 	rcu_read_unlock();
8677 	if (did_change)
8678 		sysfs_notify_dirent_safe(mddev->sysfs_state);
8679 	if (!mddev->has_superblocks)
8680 		return;
8681 	wait_event(mddev->sb_wait,
8682 		   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
8683 }
8684 EXPORT_SYMBOL(md_write_start);
8685 
8686 /* md_write_inc can only be called when md_write_start() has
8687  * already been called at least once of the current request.
8688  * It increments the counter and is useful when a single request
8689  * is split into several parts.  Each part causes an increment and
8690  * so needs a matching md_write_end().
8691  * Unlike md_write_start(), it is safe to call md_write_inc() inside
8692  * a spinlocked region.
8693  */
md_write_inc(struct mddev * mddev,struct bio * bi)8694 void md_write_inc(struct mddev *mddev, struct bio *bi)
8695 {
8696 	if (bio_data_dir(bi) != WRITE)
8697 		return;
8698 	WARN_ON_ONCE(mddev->in_sync || !md_is_rdwr(mddev));
8699 	percpu_ref_get(&mddev->writes_pending);
8700 }
8701 EXPORT_SYMBOL(md_write_inc);
8702 
md_write_end(struct mddev * mddev)8703 void md_write_end(struct mddev *mddev)
8704 {
8705 	percpu_ref_put(&mddev->writes_pending);
8706 
8707 	if (mddev->safemode == 2)
8708 		md_wakeup_thread(mddev->thread);
8709 	else if (mddev->safemode_delay)
8710 		/* The roundup() ensures this only performs locking once
8711 		 * every ->safemode_delay jiffies
8712 		 */
8713 		mod_timer(&mddev->safemode_timer,
8714 			  roundup(jiffies, mddev->safemode_delay) +
8715 			  mddev->safemode_delay);
8716 }
8717 
8718 EXPORT_SYMBOL(md_write_end);
8719 
8720 /* This is used by raid0 and raid10 */
md_submit_discard_bio(struct mddev * mddev,struct md_rdev * rdev,struct bio * bio,sector_t start,sector_t size)8721 void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
8722 			struct bio *bio, sector_t start, sector_t size)
8723 {
8724 	struct bio *discard_bio = NULL;
8725 
8726 	if (__blkdev_issue_discard(rdev->bdev, start, size, GFP_NOIO,
8727 			&discard_bio) || !discard_bio)
8728 		return;
8729 
8730 	bio_chain(discard_bio, bio);
8731 	bio_clone_blkg_association(discard_bio, bio);
8732 	mddev_trace_remap(mddev, discard_bio, bio->bi_iter.bi_sector);
8733 	submit_bio_noacct(discard_bio);
8734 }
8735 EXPORT_SYMBOL_GPL(md_submit_discard_bio);
8736 
md_bitmap_start(struct mddev * mddev,struct md_io_clone * md_io_clone)8737 static void md_bitmap_start(struct mddev *mddev,
8738 			    struct md_io_clone *md_io_clone)
8739 {
8740 	if (mddev->pers->bitmap_sector)
8741 		mddev->pers->bitmap_sector(mddev, &md_io_clone->offset,
8742 					   &md_io_clone->sectors);
8743 
8744 	mddev->bitmap_ops->startwrite(mddev, md_io_clone->offset,
8745 				      md_io_clone->sectors);
8746 }
8747 
md_bitmap_end(struct mddev * mddev,struct md_io_clone * md_io_clone)8748 static void md_bitmap_end(struct mddev *mddev, struct md_io_clone *md_io_clone)
8749 {
8750 	mddev->bitmap_ops->endwrite(mddev, md_io_clone->offset,
8751 				    md_io_clone->sectors);
8752 }
8753 
md_end_clone_io(struct bio * bio)8754 static void md_end_clone_io(struct bio *bio)
8755 {
8756 	struct md_io_clone *md_io_clone = bio->bi_private;
8757 	struct bio *orig_bio = md_io_clone->orig_bio;
8758 	struct mddev *mddev = md_io_clone->mddev;
8759 
8760 	if (bio_data_dir(orig_bio) == WRITE && mddev->bitmap)
8761 		md_bitmap_end(mddev, md_io_clone);
8762 
8763 	if (bio->bi_status && !orig_bio->bi_status)
8764 		orig_bio->bi_status = bio->bi_status;
8765 
8766 	if (md_io_clone->start_time)
8767 		bio_end_io_acct(orig_bio, md_io_clone->start_time);
8768 
8769 	bio_put(bio);
8770 	bio_endio(orig_bio);
8771 	percpu_ref_put(&mddev->active_io);
8772 }
8773 
md_clone_bio(struct mddev * mddev,struct bio ** bio)8774 static void md_clone_bio(struct mddev *mddev, struct bio **bio)
8775 {
8776 	struct block_device *bdev = (*bio)->bi_bdev;
8777 	struct md_io_clone *md_io_clone;
8778 	struct bio *clone =
8779 		bio_alloc_clone(bdev, *bio, GFP_NOIO, &mddev->io_clone_set);
8780 
8781 	md_io_clone = container_of(clone, struct md_io_clone, bio_clone);
8782 	md_io_clone->orig_bio = *bio;
8783 	md_io_clone->mddev = mddev;
8784 	if (blk_queue_io_stat(bdev->bd_disk->queue))
8785 		md_io_clone->start_time = bio_start_io_acct(*bio);
8786 
8787 	if (bio_data_dir(*bio) == WRITE && mddev->bitmap) {
8788 		md_io_clone->offset = (*bio)->bi_iter.bi_sector;
8789 		md_io_clone->sectors = bio_sectors(*bio);
8790 		md_bitmap_start(mddev, md_io_clone);
8791 	}
8792 
8793 	clone->bi_end_io = md_end_clone_io;
8794 	clone->bi_private = md_io_clone;
8795 	*bio = clone;
8796 }
8797 
md_account_bio(struct mddev * mddev,struct bio ** bio)8798 void md_account_bio(struct mddev *mddev, struct bio **bio)
8799 {
8800 	percpu_ref_get(&mddev->active_io);
8801 	md_clone_bio(mddev, bio);
8802 }
8803 EXPORT_SYMBOL_GPL(md_account_bio);
8804 
md_free_cloned_bio(struct bio * bio)8805 void md_free_cloned_bio(struct bio *bio)
8806 {
8807 	struct md_io_clone *md_io_clone = bio->bi_private;
8808 	struct bio *orig_bio = md_io_clone->orig_bio;
8809 	struct mddev *mddev = md_io_clone->mddev;
8810 
8811 	if (bio_data_dir(orig_bio) == WRITE && mddev->bitmap)
8812 		md_bitmap_end(mddev, md_io_clone);
8813 
8814 	if (bio->bi_status && !orig_bio->bi_status)
8815 		orig_bio->bi_status = bio->bi_status;
8816 
8817 	if (md_io_clone->start_time)
8818 		bio_end_io_acct(orig_bio, md_io_clone->start_time);
8819 
8820 	bio_put(bio);
8821 	percpu_ref_put(&mddev->active_io);
8822 }
8823 EXPORT_SYMBOL_GPL(md_free_cloned_bio);
8824 
8825 /* md_allow_write(mddev)
8826  * Calling this ensures that the array is marked 'active' so that writes
8827  * may proceed without blocking.  It is important to call this before
8828  * attempting a GFP_KERNEL allocation while holding the mddev lock.
8829  * Must be called with mddev_lock held.
8830  */
md_allow_write(struct mddev * mddev)8831 void md_allow_write(struct mddev *mddev)
8832 {
8833 	if (!mddev->pers)
8834 		return;
8835 	if (!md_is_rdwr(mddev))
8836 		return;
8837 	if (!mddev->pers->sync_request)
8838 		return;
8839 
8840 	spin_lock(&mddev->lock);
8841 	if (mddev->in_sync) {
8842 		mddev->in_sync = 0;
8843 		set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
8844 		set_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
8845 		if (mddev->safemode_delay &&
8846 		    mddev->safemode == 0)
8847 			mddev->safemode = 1;
8848 		spin_unlock(&mddev->lock);
8849 		md_update_sb(mddev, 0);
8850 		sysfs_notify_dirent_safe(mddev->sysfs_state);
8851 		/* wait for the dirty state to be recorded in the metadata */
8852 		wait_event(mddev->sb_wait,
8853 			   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
8854 	} else
8855 		spin_unlock(&mddev->lock);
8856 }
8857 EXPORT_SYMBOL_GPL(md_allow_write);
8858 
md_sync_max_sectors(struct mddev * mddev,enum sync_action action)8859 static sector_t md_sync_max_sectors(struct mddev *mddev,
8860 				    enum sync_action action)
8861 {
8862 	switch (action) {
8863 	case ACTION_RESYNC:
8864 	case ACTION_CHECK:
8865 	case ACTION_REPAIR:
8866 		atomic64_set(&mddev->resync_mismatches, 0);
8867 		fallthrough;
8868 	case ACTION_RESHAPE:
8869 		return mddev->resync_max_sectors;
8870 	case ACTION_RECOVER:
8871 		return mddev->dev_sectors;
8872 	default:
8873 		return 0;
8874 	}
8875 }
8876 
md_sync_position(struct mddev * mddev,enum sync_action action)8877 static sector_t md_sync_position(struct mddev *mddev, enum sync_action action)
8878 {
8879 	sector_t start = 0;
8880 	struct md_rdev *rdev;
8881 
8882 	switch (action) {
8883 	case ACTION_CHECK:
8884 	case ACTION_REPAIR:
8885 		return mddev->resync_min;
8886 	case ACTION_RESYNC:
8887 		if (!mddev->bitmap)
8888 			return mddev->recovery_cp;
8889 		return 0;
8890 	case ACTION_RESHAPE:
8891 		/*
8892 		 * If the original node aborts reshaping then we continue the
8893 		 * reshaping, so set again to avoid restart reshape from the
8894 		 * first beginning
8895 		 */
8896 		if (mddev_is_clustered(mddev) &&
8897 		    mddev->reshape_position != MaxSector)
8898 			return mddev->reshape_position;
8899 		return 0;
8900 	case ACTION_RECOVER:
8901 		start = MaxSector;
8902 		rcu_read_lock();
8903 		rdev_for_each_rcu(rdev, mddev)
8904 			if (rdev->raid_disk >= 0 &&
8905 			    !test_bit(Journal, &rdev->flags) &&
8906 			    !test_bit(Faulty, &rdev->flags) &&
8907 			    !test_bit(In_sync, &rdev->flags) &&
8908 			    rdev->recovery_offset < start)
8909 				start = rdev->recovery_offset;
8910 		rcu_read_unlock();
8911 
8912 		/* If there is a bitmap, we need to make sure all
8913 		 * writes that started before we added a spare
8914 		 * complete before we start doing a recovery.
8915 		 * Otherwise the write might complete and (via
8916 		 * bitmap_endwrite) set a bit in the bitmap after the
8917 		 * recovery has checked that bit and skipped that
8918 		 * region.
8919 		 */
8920 		if (mddev->bitmap) {
8921 			mddev->pers->quiesce(mddev, 1);
8922 			mddev->pers->quiesce(mddev, 0);
8923 		}
8924 		return start;
8925 	default:
8926 		return MaxSector;
8927 	}
8928 }
8929 
8930 #define SYNC_MARKS	10
8931 #define	SYNC_MARK_STEP	(3*HZ)
8932 #define UPDATE_FREQUENCY (5*60*HZ)
md_do_sync(struct md_thread * thread)8933 void md_do_sync(struct md_thread *thread)
8934 {
8935 	struct mddev *mddev = thread->mddev;
8936 	struct mddev *mddev2;
8937 	unsigned int currspeed = 0, window;
8938 	sector_t max_sectors,j, io_sectors, recovery_done;
8939 	unsigned long mark[SYNC_MARKS];
8940 	unsigned long update_time;
8941 	sector_t mark_cnt[SYNC_MARKS];
8942 	int last_mark,m;
8943 	sector_t last_check;
8944 	int skipped = 0;
8945 	struct md_rdev *rdev;
8946 	enum sync_action action;
8947 	const char *desc;
8948 	struct blk_plug plug;
8949 	int ret;
8950 
8951 	/* just incase thread restarts... */
8952 	if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
8953 		return;
8954 
8955 	if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
8956 		goto skip;
8957 
8958 	if (test_bit(MD_RECOVERY_WAIT, &mddev->recovery) ||
8959 	    !md_is_rdwr(mddev)) {/* never try to sync a read-only array */
8960 		set_bit(MD_RECOVERY_INTR, &mddev->recovery);
8961 		goto skip;
8962 	}
8963 
8964 	if (mddev_is_clustered(mddev)) {
8965 		ret = mddev->cluster_ops->resync_start(mddev);
8966 		if (ret)
8967 			goto skip;
8968 
8969 		set_bit(MD_CLUSTER_RESYNC_LOCKED, &mddev->flags);
8970 		if (!(test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
8971 			test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
8972 			test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
8973 		     && ((unsigned long long)mddev->curr_resync_completed
8974 			 < (unsigned long long)mddev->resync_max_sectors))
8975 			goto skip;
8976 	}
8977 
8978 	action = md_sync_action(mddev);
8979 	desc = md_sync_action_name(action);
8980 	mddev->last_sync_action = action;
8981 
8982 	/*
8983 	 * Before starting a resync we must have set curr_resync to
8984 	 * 2, and then checked that every "conflicting" array has curr_resync
8985 	 * less than ours.  When we find one that is the same or higher
8986 	 * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
8987 	 * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
8988 	 * This will mean we have to start checking from the beginning again.
8989 	 *
8990 	 */
8991 	if (mddev_is_clustered(mddev))
8992 		mddev->cluster_ops->resync_start_notify(mddev);
8993 	do {
8994 		int mddev2_minor = -1;
8995 		mddev->curr_resync = MD_RESYNC_DELAYED;
8996 
8997 	try_again:
8998 		if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
8999 			goto skip;
9000 		spin_lock(&all_mddevs_lock);
9001 		list_for_each_entry(mddev2, &all_mddevs, all_mddevs) {
9002 			if (test_bit(MD_DELETED, &mddev2->flags))
9003 				continue;
9004 			if (mddev2 == mddev)
9005 				continue;
9006 			if (!mddev->parallel_resync
9007 			&&  mddev2->curr_resync
9008 			&&  match_mddev_units(mddev, mddev2)) {
9009 				DEFINE_WAIT(wq);
9010 				if (mddev < mddev2 &&
9011 				    mddev->curr_resync == MD_RESYNC_DELAYED) {
9012 					/* arbitrarily yield */
9013 					mddev->curr_resync = MD_RESYNC_YIELDED;
9014 					wake_up(&resync_wait);
9015 				}
9016 				if (mddev > mddev2 &&
9017 				    mddev->curr_resync == MD_RESYNC_YIELDED)
9018 					/* no need to wait here, we can wait the next
9019 					 * time 'round when curr_resync == 2
9020 					 */
9021 					continue;
9022 				/* We need to wait 'interruptible' so as not to
9023 				 * contribute to the load average, and not to
9024 				 * be caught by 'softlockup'
9025 				 */
9026 				prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
9027 				if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
9028 				    mddev2->curr_resync >= mddev->curr_resync) {
9029 					if (mddev2_minor != mddev2->md_minor) {
9030 						mddev2_minor = mddev2->md_minor;
9031 						pr_info("md: delaying %s of %s until %s has finished (they share one or more physical units)\n",
9032 							desc, mdname(mddev),
9033 							mdname(mddev2));
9034 					}
9035 					spin_unlock(&all_mddevs_lock);
9036 
9037 					if (signal_pending(current))
9038 						flush_signals(current);
9039 					schedule();
9040 					finish_wait(&resync_wait, &wq);
9041 					goto try_again;
9042 				}
9043 				finish_wait(&resync_wait, &wq);
9044 			}
9045 		}
9046 		spin_unlock(&all_mddevs_lock);
9047 	} while (mddev->curr_resync < MD_RESYNC_DELAYED);
9048 
9049 	max_sectors = md_sync_max_sectors(mddev, action);
9050 	j = md_sync_position(mddev, action);
9051 
9052 	pr_info("md: %s of RAID array %s\n", desc, mdname(mddev));
9053 	pr_debug("md: minimum _guaranteed_  speed: %d KB/sec/disk.\n", speed_min(mddev));
9054 	pr_debug("md: using maximum available idle IO bandwidth (but not more than %d KB/sec) for %s.\n",
9055 		 speed_max(mddev), desc);
9056 
9057 	is_mddev_idle(mddev, 1); /* this initializes IO event counters */
9058 
9059 	io_sectors = 0;
9060 	for (m = 0; m < SYNC_MARKS; m++) {
9061 		mark[m] = jiffies;
9062 		mark_cnt[m] = io_sectors;
9063 	}
9064 	last_mark = 0;
9065 	mddev->resync_mark = mark[last_mark];
9066 	mddev->resync_mark_cnt = mark_cnt[last_mark];
9067 
9068 	/*
9069 	 * Tune reconstruction:
9070 	 */
9071 	window = 32 * (PAGE_SIZE / 512);
9072 	pr_debug("md: using %dk window, over a total of %lluk.\n",
9073 		 window/2, (unsigned long long)max_sectors/2);
9074 
9075 	atomic_set(&mddev->recovery_active, 0);
9076 	last_check = 0;
9077 
9078 	if (j >= MD_RESYNC_ACTIVE) {
9079 		pr_debug("md: resuming %s of %s from checkpoint.\n",
9080 			 desc, mdname(mddev));
9081 		mddev->curr_resync = j;
9082 	} else
9083 		mddev->curr_resync = MD_RESYNC_ACTIVE; /* no longer delayed */
9084 	mddev->curr_resync_completed = j;
9085 	sysfs_notify_dirent_safe(mddev->sysfs_completed);
9086 	md_new_event();
9087 	update_time = jiffies;
9088 
9089 	blk_start_plug(&plug);
9090 	while (j < max_sectors) {
9091 		sector_t sectors;
9092 
9093 		skipped = 0;
9094 
9095 		if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9096 		    ((mddev->curr_resync > mddev->curr_resync_completed &&
9097 		      (mddev->curr_resync - mddev->curr_resync_completed)
9098 		      > (max_sectors >> 4)) ||
9099 		     time_after_eq(jiffies, update_time + UPDATE_FREQUENCY) ||
9100 		     (j - mddev->curr_resync_completed)*2
9101 		     >= mddev->resync_max - mddev->curr_resync_completed ||
9102 		     mddev->curr_resync_completed > mddev->resync_max
9103 			    )) {
9104 			/* time to update curr_resync_completed */
9105 			wait_event(mddev->recovery_wait,
9106 				   atomic_read(&mddev->recovery_active) == 0);
9107 			mddev->curr_resync_completed = j;
9108 			if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
9109 			    j > mddev->recovery_cp)
9110 				mddev->recovery_cp = j;
9111 			update_time = jiffies;
9112 			set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
9113 			sysfs_notify_dirent_safe(mddev->sysfs_completed);
9114 		}
9115 
9116 		while (j >= mddev->resync_max &&
9117 		       !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
9118 			/* As this condition is controlled by user-space,
9119 			 * we can block indefinitely, so use '_interruptible'
9120 			 * to avoid triggering warnings.
9121 			 */
9122 			flush_signals(current); /* just in case */
9123 			wait_event_interruptible(mddev->recovery_wait,
9124 						 mddev->resync_max > j
9125 						 || test_bit(MD_RECOVERY_INTR,
9126 							     &mddev->recovery));
9127 		}
9128 
9129 		if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
9130 			break;
9131 
9132 		sectors = mddev->pers->sync_request(mddev, j, max_sectors,
9133 						    &skipped);
9134 		if (sectors == 0) {
9135 			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
9136 			break;
9137 		}
9138 
9139 		if (!skipped) { /* actual IO requested */
9140 			io_sectors += sectors;
9141 			atomic_add(sectors, &mddev->recovery_active);
9142 		}
9143 
9144 		if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
9145 			break;
9146 
9147 		j += sectors;
9148 		if (j > max_sectors)
9149 			/* when skipping, extra large numbers can be returned. */
9150 			j = max_sectors;
9151 		if (j >= MD_RESYNC_ACTIVE)
9152 			mddev->curr_resync = j;
9153 		mddev->curr_mark_cnt = io_sectors;
9154 		if (last_check == 0)
9155 			/* this is the earliest that rebuild will be
9156 			 * visible in /proc/mdstat
9157 			 */
9158 			md_new_event();
9159 
9160 		if (last_check + window > io_sectors || j == max_sectors)
9161 			continue;
9162 
9163 		last_check = io_sectors;
9164 	repeat:
9165 		if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
9166 			/* step marks */
9167 			int next = (last_mark+1) % SYNC_MARKS;
9168 
9169 			mddev->resync_mark = mark[next];
9170 			mddev->resync_mark_cnt = mark_cnt[next];
9171 			mark[next] = jiffies;
9172 			mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
9173 			last_mark = next;
9174 		}
9175 
9176 		if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
9177 			break;
9178 
9179 		/*
9180 		 * this loop exits only if either when we are slower than
9181 		 * the 'hard' speed limit, or the system was IO-idle for
9182 		 * a jiffy.
9183 		 * the system might be non-idle CPU-wise, but we only care
9184 		 * about not overloading the IO subsystem. (things like an
9185 		 * e2fsck being done on the RAID array should execute fast)
9186 		 */
9187 		cond_resched();
9188 
9189 		recovery_done = io_sectors - atomic_read(&mddev->recovery_active);
9190 		currspeed = ((unsigned long)(recovery_done - mddev->resync_mark_cnt))/2
9191 			/((jiffies-mddev->resync_mark)/HZ +1) +1;
9192 
9193 		if (currspeed > speed_min(mddev)) {
9194 			if (currspeed > speed_max(mddev)) {
9195 				msleep(500);
9196 				goto repeat;
9197 			}
9198 			if (!is_mddev_idle(mddev, 0)) {
9199 				/*
9200 				 * Give other IO more of a chance.
9201 				 * The faster the devices, the less we wait.
9202 				 */
9203 				wait_event(mddev->recovery_wait,
9204 					   !atomic_read(&mddev->recovery_active));
9205 			}
9206 		}
9207 	}
9208 	pr_info("md: %s: %s %s.\n",mdname(mddev), desc,
9209 		test_bit(MD_RECOVERY_INTR, &mddev->recovery)
9210 		? "interrupted" : "done");
9211 	/*
9212 	 * this also signals 'finished resyncing' to md_stop
9213 	 */
9214 	blk_finish_plug(&plug);
9215 	wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
9216 
9217 	if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9218 	    !test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
9219 	    mddev->curr_resync >= MD_RESYNC_ACTIVE) {
9220 		mddev->curr_resync_completed = mddev->curr_resync;
9221 		sysfs_notify_dirent_safe(mddev->sysfs_completed);
9222 	}
9223 	mddev->pers->sync_request(mddev, max_sectors, max_sectors, &skipped);
9224 
9225 	if (!test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
9226 	    mddev->curr_resync > MD_RESYNC_ACTIVE) {
9227 		if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
9228 			if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
9229 				if (mddev->curr_resync >= mddev->recovery_cp) {
9230 					pr_debug("md: checkpointing %s of %s.\n",
9231 						 desc, mdname(mddev));
9232 					if (test_bit(MD_RECOVERY_ERROR,
9233 						&mddev->recovery))
9234 						mddev->recovery_cp =
9235 							mddev->curr_resync_completed;
9236 					else
9237 						mddev->recovery_cp =
9238 							mddev->curr_resync;
9239 				}
9240 			} else
9241 				mddev->recovery_cp = MaxSector;
9242 		} else {
9243 			if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
9244 				mddev->curr_resync = MaxSector;
9245 			if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9246 			    test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) {
9247 				rcu_read_lock();
9248 				rdev_for_each_rcu(rdev, mddev)
9249 					if (rdev->raid_disk >= 0 &&
9250 					    mddev->delta_disks >= 0 &&
9251 					    !test_bit(Journal, &rdev->flags) &&
9252 					    !test_bit(Faulty, &rdev->flags) &&
9253 					    !test_bit(In_sync, &rdev->flags) &&
9254 					    rdev->recovery_offset < mddev->curr_resync)
9255 						rdev->recovery_offset = mddev->curr_resync;
9256 				rcu_read_unlock();
9257 			}
9258 		}
9259 	}
9260  skip:
9261 	/* set CHANGE_PENDING here since maybe another update is needed,
9262 	 * so other nodes are informed. It should be harmless for normal
9263 	 * raid */
9264 	set_mask_bits(&mddev->sb_flags, 0,
9265 		      BIT(MD_SB_CHANGE_PENDING) | BIT(MD_SB_CHANGE_DEVS));
9266 
9267 	if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9268 			!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
9269 			mddev->delta_disks > 0 &&
9270 			mddev->pers->finish_reshape &&
9271 			mddev->pers->size &&
9272 			!mddev_is_dm(mddev)) {
9273 		mddev_lock_nointr(mddev);
9274 		md_set_array_sectors(mddev, mddev->pers->size(mddev, 0, 0));
9275 		mddev_unlock(mddev);
9276 		if (!mddev_is_clustered(mddev))
9277 			set_capacity_and_notify(mddev->gendisk,
9278 						mddev->array_sectors);
9279 	}
9280 
9281 	spin_lock(&mddev->lock);
9282 	if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
9283 		/* We completed so min/max setting can be forgotten if used. */
9284 		if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
9285 			mddev->resync_min = 0;
9286 		mddev->resync_max = MaxSector;
9287 	} else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
9288 		mddev->resync_min = mddev->curr_resync_completed;
9289 	set_bit(MD_RECOVERY_DONE, &mddev->recovery);
9290 	mddev->curr_resync = MD_RESYNC_NONE;
9291 	spin_unlock(&mddev->lock);
9292 
9293 	wake_up(&resync_wait);
9294 	md_wakeup_thread(mddev->thread);
9295 	return;
9296 }
9297 EXPORT_SYMBOL_GPL(md_do_sync);
9298 
rdev_removeable(struct md_rdev * rdev)9299 static bool rdev_removeable(struct md_rdev *rdev)
9300 {
9301 	/* rdev is not used. */
9302 	if (rdev->raid_disk < 0)
9303 		return false;
9304 
9305 	/* There are still inflight io, don't remove this rdev. */
9306 	if (atomic_read(&rdev->nr_pending))
9307 		return false;
9308 
9309 	/*
9310 	 * An error occurred but has not yet been acknowledged by the metadata
9311 	 * handler, don't remove this rdev.
9312 	 */
9313 	if (test_bit(Blocked, &rdev->flags))
9314 		return false;
9315 
9316 	/* Fautly rdev is not used, it's safe to remove it. */
9317 	if (test_bit(Faulty, &rdev->flags))
9318 		return true;
9319 
9320 	/* Journal disk can only be removed if it's faulty. */
9321 	if (test_bit(Journal, &rdev->flags))
9322 		return false;
9323 
9324 	/*
9325 	 * 'In_sync' is cleared while 'raid_disk' is valid, which means
9326 	 * replacement has just become active from pers->spare_active(), and
9327 	 * then pers->hot_remove_disk() will replace this rdev with replacement.
9328 	 */
9329 	if (!test_bit(In_sync, &rdev->flags))
9330 		return true;
9331 
9332 	return false;
9333 }
9334 
rdev_is_spare(struct md_rdev * rdev)9335 static bool rdev_is_spare(struct md_rdev *rdev)
9336 {
9337 	return !test_bit(Candidate, &rdev->flags) && rdev->raid_disk >= 0 &&
9338 	       !test_bit(In_sync, &rdev->flags) &&
9339 	       !test_bit(Journal, &rdev->flags) &&
9340 	       !test_bit(Faulty, &rdev->flags);
9341 }
9342 
rdev_addable(struct md_rdev * rdev)9343 static bool rdev_addable(struct md_rdev *rdev)
9344 {
9345 	/* rdev is already used, don't add it again. */
9346 	if (test_bit(Candidate, &rdev->flags) || rdev->raid_disk >= 0 ||
9347 	    test_bit(Faulty, &rdev->flags))
9348 		return false;
9349 
9350 	/* Allow to add journal disk. */
9351 	if (test_bit(Journal, &rdev->flags))
9352 		return true;
9353 
9354 	/* Allow to add if array is read-write. */
9355 	if (md_is_rdwr(rdev->mddev))
9356 		return true;
9357 
9358 	/*
9359 	 * For read-only array, only allow to readd a rdev. And if bitmap is
9360 	 * used, don't allow to readd a rdev that is too old.
9361 	 */
9362 	if (rdev->saved_raid_disk >= 0 && !test_bit(Bitmap_sync, &rdev->flags))
9363 		return true;
9364 
9365 	return false;
9366 }
9367 
md_spares_need_change(struct mddev * mddev)9368 static bool md_spares_need_change(struct mddev *mddev)
9369 {
9370 	struct md_rdev *rdev;
9371 
9372 	rcu_read_lock();
9373 	rdev_for_each_rcu(rdev, mddev) {
9374 		if (rdev_removeable(rdev) || rdev_addable(rdev)) {
9375 			rcu_read_unlock();
9376 			return true;
9377 		}
9378 	}
9379 	rcu_read_unlock();
9380 	return false;
9381 }
9382 
remove_and_add_spares(struct mddev * mddev,struct md_rdev * this)9383 static int remove_and_add_spares(struct mddev *mddev,
9384 				 struct md_rdev *this)
9385 {
9386 	struct md_rdev *rdev;
9387 	int spares = 0;
9388 	int removed = 0;
9389 
9390 	if (this && test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
9391 		/* Mustn't remove devices when resync thread is running */
9392 		return 0;
9393 
9394 	rdev_for_each(rdev, mddev) {
9395 		if ((this == NULL || rdev == this) && rdev_removeable(rdev) &&
9396 		    !mddev->pers->hot_remove_disk(mddev, rdev)) {
9397 			sysfs_unlink_rdev(mddev, rdev);
9398 			rdev->saved_raid_disk = rdev->raid_disk;
9399 			rdev->raid_disk = -1;
9400 			removed++;
9401 		}
9402 	}
9403 
9404 	if (removed && mddev->kobj.sd)
9405 		sysfs_notify_dirent_safe(mddev->sysfs_degraded);
9406 
9407 	if (this && removed)
9408 		goto no_add;
9409 
9410 	rdev_for_each(rdev, mddev) {
9411 		if (this && this != rdev)
9412 			continue;
9413 		if (rdev_is_spare(rdev))
9414 			spares++;
9415 		if (!rdev_addable(rdev))
9416 			continue;
9417 		if (!test_bit(Journal, &rdev->flags))
9418 			rdev->recovery_offset = 0;
9419 		if (mddev->pers->hot_add_disk(mddev, rdev) == 0) {
9420 			/* failure here is OK */
9421 			sysfs_link_rdev(mddev, rdev);
9422 			if (!test_bit(Journal, &rdev->flags))
9423 				spares++;
9424 			md_new_event();
9425 			set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
9426 		}
9427 	}
9428 no_add:
9429 	if (removed)
9430 		set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
9431 	return spares;
9432 }
9433 
md_choose_sync_action(struct mddev * mddev,int * spares)9434 static bool md_choose_sync_action(struct mddev *mddev, int *spares)
9435 {
9436 	/* Check if reshape is in progress first. */
9437 	if (mddev->reshape_position != MaxSector) {
9438 		if (mddev->pers->check_reshape == NULL ||
9439 		    mddev->pers->check_reshape(mddev) != 0)
9440 			return false;
9441 
9442 		set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
9443 		clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9444 		return true;
9445 	}
9446 
9447 	/* Check if resync is in progress. */
9448 	if (mddev->recovery_cp < MaxSector) {
9449 		set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9450 		clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9451 		return true;
9452 	}
9453 
9454 	/*
9455 	 * Remove any failed drives, then add spares if possible. Spares are
9456 	 * also removed and re-added, to allow the personality to fail the
9457 	 * re-add.
9458 	 */
9459 	*spares = remove_and_add_spares(mddev, NULL);
9460 	if (*spares) {
9461 		clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9462 		clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
9463 		clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
9464 
9465 		/* Start new recovery. */
9466 		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9467 		return true;
9468 	}
9469 
9470 	/* Delay to choose resync/check/repair in md_do_sync(). */
9471 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
9472 		return true;
9473 
9474 	/* Nothing to be done */
9475 	return false;
9476 }
9477 
md_start_sync(struct work_struct * ws)9478 static void md_start_sync(struct work_struct *ws)
9479 {
9480 	struct mddev *mddev = container_of(ws, struct mddev, sync_work);
9481 	int spares = 0;
9482 	bool suspend = false;
9483 	char *name;
9484 
9485 	/*
9486 	 * If reshape is still in progress, spares won't be added or removed
9487 	 * from conf until reshape is done.
9488 	 */
9489 	if (mddev->reshape_position == MaxSector &&
9490 	    md_spares_need_change(mddev)) {
9491 		suspend = true;
9492 		mddev_suspend(mddev, false);
9493 	}
9494 
9495 	mddev_lock_nointr(mddev);
9496 	if (!md_is_rdwr(mddev)) {
9497 		/*
9498 		 * On a read-only array we can:
9499 		 * - remove failed devices
9500 		 * - add already-in_sync devices if the array itself is in-sync.
9501 		 * As we only add devices that are already in-sync, we can
9502 		 * activate the spares immediately.
9503 		 */
9504 		remove_and_add_spares(mddev, NULL);
9505 		goto not_running;
9506 	}
9507 
9508 	if (!md_choose_sync_action(mddev, &spares))
9509 		goto not_running;
9510 
9511 	if (!mddev->pers->sync_request)
9512 		goto not_running;
9513 
9514 	/*
9515 	 * We are adding a device or devices to an array which has the bitmap
9516 	 * stored on all devices. So make sure all bitmap pages get written.
9517 	 */
9518 	if (spares)
9519 		mddev->bitmap_ops->write_all(mddev);
9520 
9521 	name = test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ?
9522 			"reshape" : "resync";
9523 	rcu_assign_pointer(mddev->sync_thread,
9524 			   md_register_thread(md_do_sync, mddev, name));
9525 	if (!mddev->sync_thread) {
9526 		pr_warn("%s: could not start resync thread...\n",
9527 			mdname(mddev));
9528 		/* leave the spares where they are, it shouldn't hurt */
9529 		goto not_running;
9530 	}
9531 
9532 	mddev_unlock(mddev);
9533 	/*
9534 	 * md_start_sync was triggered by MD_RECOVERY_NEEDED, so we should
9535 	 * not set it again. Otherwise, we may cause issue like this one:
9536 	 *     https://bugzilla.kernel.org/show_bug.cgi?id=218200
9537 	 * Therefore, use __mddev_resume(mddev, false).
9538 	 */
9539 	if (suspend)
9540 		__mddev_resume(mddev, false);
9541 	md_wakeup_thread(mddev->sync_thread);
9542 	sysfs_notify_dirent_safe(mddev->sysfs_action);
9543 	md_new_event();
9544 	return;
9545 
9546 not_running:
9547 	clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9548 	clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
9549 	clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
9550 	clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
9551 	clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9552 	mddev_unlock(mddev);
9553 	/*
9554 	 * md_start_sync was triggered by MD_RECOVERY_NEEDED, so we should
9555 	 * not set it again. Otherwise, we may cause issue like this one:
9556 	 *     https://bugzilla.kernel.org/show_bug.cgi?id=218200
9557 	 * Therefore, use __mddev_resume(mddev, false).
9558 	 */
9559 	if (suspend)
9560 		__mddev_resume(mddev, false);
9561 
9562 	wake_up(&resync_wait);
9563 	if (test_and_clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery) &&
9564 	    mddev->sysfs_action)
9565 		sysfs_notify_dirent_safe(mddev->sysfs_action);
9566 }
9567 
unregister_sync_thread(struct mddev * mddev)9568 static void unregister_sync_thread(struct mddev *mddev)
9569 {
9570 	if (!test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
9571 		/* resync/recovery still happening */
9572 		clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9573 		return;
9574 	}
9575 
9576 	if (WARN_ON_ONCE(!mddev->sync_thread))
9577 		return;
9578 
9579 	md_reap_sync_thread(mddev);
9580 }
9581 
9582 /*
9583  * This routine is regularly called by all per-raid-array threads to
9584  * deal with generic issues like resync and super-block update.
9585  * Raid personalities that don't have a thread (linear/raid0) do not
9586  * need this as they never do any recovery or update the superblock.
9587  *
9588  * It does not do any resync itself, but rather "forks" off other threads
9589  * to do that as needed.
9590  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
9591  * "->recovery" and create a thread at ->sync_thread.
9592  * When the thread finishes it sets MD_RECOVERY_DONE
9593  * and wakeups up this thread which will reap the thread and finish up.
9594  * This thread also removes any faulty devices (with nr_pending == 0).
9595  *
9596  * The overall approach is:
9597  *  1/ if the superblock needs updating, update it.
9598  *  2/ If a recovery thread is running, don't do anything else.
9599  *  3/ If recovery has finished, clean up, possibly marking spares active.
9600  *  4/ If there are any faulty devices, remove them.
9601  *  5/ If array is degraded, try to add spares devices
9602  *  6/ If array has spares or is not in-sync, start a resync thread.
9603  */
md_check_recovery(struct mddev * mddev)9604 void md_check_recovery(struct mddev *mddev)
9605 {
9606 	if (mddev->bitmap)
9607 		mddev->bitmap_ops->daemon_work(mddev);
9608 
9609 	if (signal_pending(current)) {
9610 		if (mddev->pers->sync_request && !mddev->external) {
9611 			pr_debug("md: %s in immediate safe mode\n",
9612 				 mdname(mddev));
9613 			mddev->safemode = 2;
9614 		}
9615 		flush_signals(current);
9616 	}
9617 
9618 	if (!md_is_rdwr(mddev) &&
9619 	    !test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) &&
9620 	    !test_bit(MD_RECOVERY_DONE, &mddev->recovery))
9621 		return;
9622 	if ( ! (
9623 		(mddev->sb_flags & ~ (1<<MD_SB_CHANGE_PENDING)) ||
9624 		test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
9625 		test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
9626 		(mddev->external == 0 && mddev->safemode == 1) ||
9627 		(mddev->safemode == 2
9628 		 && !mddev->in_sync && mddev->recovery_cp == MaxSector)
9629 		))
9630 		return;
9631 
9632 	if (mddev_trylock(mddev)) {
9633 		bool try_set_sync = mddev->safemode != 0;
9634 
9635 		if (!mddev->external && mddev->safemode == 1)
9636 			mddev->safemode = 0;
9637 
9638 		if (!md_is_rdwr(mddev)) {
9639 			struct md_rdev *rdev;
9640 
9641 			if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
9642 				unregister_sync_thread(mddev);
9643 				goto unlock;
9644 			}
9645 
9646 			if (!mddev->external && mddev->in_sync)
9647 				/*
9648 				 * 'Blocked' flag not needed as failed devices
9649 				 * will be recorded if array switched to read/write.
9650 				 * Leaving it set will prevent the device
9651 				 * from being removed.
9652 				 */
9653 				rdev_for_each(rdev, mddev)
9654 					clear_bit(Blocked, &rdev->flags);
9655 
9656 			/*
9657 			 * There is no thread, but we need to call
9658 			 * ->spare_active and clear saved_raid_disk
9659 			 */
9660 			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
9661 			md_reap_sync_thread(mddev);
9662 
9663 			/*
9664 			 * Let md_start_sync() to remove and add rdevs to the
9665 			 * array.
9666 			 */
9667 			if (md_spares_need_change(mddev)) {
9668 				set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9669 				queue_work(md_misc_wq, &mddev->sync_work);
9670 			}
9671 
9672 			clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9673 			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9674 			clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
9675 
9676 			goto unlock;
9677 		}
9678 
9679 		if (mddev_is_clustered(mddev)) {
9680 			struct md_rdev *rdev, *tmp;
9681 			/* kick the device if another node issued a
9682 			 * remove disk.
9683 			 */
9684 			rdev_for_each_safe(rdev, tmp, mddev) {
9685 				if (test_and_clear_bit(ClusterRemove, &rdev->flags) &&
9686 						rdev->raid_disk < 0)
9687 					md_kick_rdev_from_array(rdev);
9688 			}
9689 		}
9690 
9691 		if (try_set_sync && !mddev->external && !mddev->in_sync) {
9692 			spin_lock(&mddev->lock);
9693 			set_in_sync(mddev);
9694 			spin_unlock(&mddev->lock);
9695 		}
9696 
9697 		if (mddev->sb_flags)
9698 			md_update_sb(mddev, 0);
9699 
9700 		/*
9701 		 * Never start a new sync thread if MD_RECOVERY_RUNNING is
9702 		 * still set.
9703 		 */
9704 		if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
9705 			unregister_sync_thread(mddev);
9706 			goto unlock;
9707 		}
9708 
9709 		/* Set RUNNING before clearing NEEDED to avoid
9710 		 * any transients in the value of "sync_action".
9711 		 */
9712 		mddev->curr_resync_completed = 0;
9713 		spin_lock(&mddev->lock);
9714 		set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9715 		spin_unlock(&mddev->lock);
9716 		/* Clear some bits that don't mean anything, but
9717 		 * might be left set
9718 		 */
9719 		clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
9720 		clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
9721 
9722 		if (test_and_clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery) &&
9723 		    !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
9724 			queue_work(md_misc_wq, &mddev->sync_work);
9725 		} else {
9726 			clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9727 			wake_up(&resync_wait);
9728 		}
9729 
9730 	unlock:
9731 		wake_up(&mddev->sb_wait);
9732 		mddev_unlock(mddev);
9733 	}
9734 }
9735 EXPORT_SYMBOL(md_check_recovery);
9736 
md_reap_sync_thread(struct mddev * mddev)9737 void md_reap_sync_thread(struct mddev *mddev)
9738 {
9739 	struct md_rdev *rdev;
9740 	sector_t old_dev_sectors = mddev->dev_sectors;
9741 	bool is_reshaped = false;
9742 
9743 	/* resync has finished, collect result */
9744 	md_unregister_thread(mddev, &mddev->sync_thread);
9745 	atomic_inc(&mddev->sync_seq);
9746 
9747 	if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
9748 	    !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
9749 	    mddev->degraded != mddev->raid_disks) {
9750 		/* success...*/
9751 		/* activate any spares */
9752 		if (mddev->pers->spare_active(mddev)) {
9753 			sysfs_notify_dirent_safe(mddev->sysfs_degraded);
9754 			set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
9755 		}
9756 	}
9757 	if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9758 	    mddev->pers->finish_reshape) {
9759 		mddev->pers->finish_reshape(mddev);
9760 		if (mddev_is_clustered(mddev))
9761 			is_reshaped = true;
9762 	}
9763 
9764 	/* If array is no-longer degraded, then any saved_raid_disk
9765 	 * information must be scrapped.
9766 	 */
9767 	if (!mddev->degraded)
9768 		rdev_for_each(rdev, mddev)
9769 			rdev->saved_raid_disk = -1;
9770 
9771 	md_update_sb(mddev, 1);
9772 	/* MD_SB_CHANGE_PENDING should be cleared by md_update_sb, so we can
9773 	 * call resync_finish here if MD_CLUSTER_RESYNC_LOCKED is set by
9774 	 * clustered raid */
9775 	if (test_and_clear_bit(MD_CLUSTER_RESYNC_LOCKED, &mddev->flags))
9776 		mddev->cluster_ops->resync_finish(mddev);
9777 	clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9778 	clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
9779 	clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9780 	clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
9781 	clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
9782 	clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
9783 	/*
9784 	 * We call mddev->cluster_ops->update_size here because sync_size could
9785 	 * be changed by md_update_sb, and MD_RECOVERY_RESHAPE is cleared,
9786 	 * so it is time to update size across cluster.
9787 	 */
9788 	if (mddev_is_clustered(mddev) && is_reshaped
9789 				      && !test_bit(MD_CLOSING, &mddev->flags))
9790 		mddev->cluster_ops->update_size(mddev, old_dev_sectors);
9791 	/* flag recovery needed just to double check */
9792 	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9793 	sysfs_notify_dirent_safe(mddev->sysfs_completed);
9794 	sysfs_notify_dirent_safe(mddev->sysfs_action);
9795 	md_new_event();
9796 	if (mddev->event_work.func)
9797 		queue_work(md_misc_wq, &mddev->event_work);
9798 	wake_up(&resync_wait);
9799 }
9800 EXPORT_SYMBOL(md_reap_sync_thread);
9801 
md_wait_for_blocked_rdev(struct md_rdev * rdev,struct mddev * mddev)9802 void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev)
9803 {
9804 	sysfs_notify_dirent_safe(rdev->sysfs_state);
9805 	wait_event_timeout(rdev->blocked_wait, !rdev_blocked(rdev),
9806 			   msecs_to_jiffies(5000));
9807 	rdev_dec_pending(rdev, mddev);
9808 }
9809 EXPORT_SYMBOL(md_wait_for_blocked_rdev);
9810 
md_finish_reshape(struct mddev * mddev)9811 void md_finish_reshape(struct mddev *mddev)
9812 {
9813 	/* called be personality module when reshape completes. */
9814 	struct md_rdev *rdev;
9815 
9816 	rdev_for_each(rdev, mddev) {
9817 		if (rdev->data_offset > rdev->new_data_offset)
9818 			rdev->sectors += rdev->data_offset - rdev->new_data_offset;
9819 		else
9820 			rdev->sectors -= rdev->new_data_offset - rdev->data_offset;
9821 		rdev->data_offset = rdev->new_data_offset;
9822 	}
9823 }
9824 EXPORT_SYMBOL(md_finish_reshape);
9825 
9826 /* Bad block management */
9827 
9828 /* Returns true on success, false on failure */
rdev_set_badblocks(struct md_rdev * rdev,sector_t s,int sectors,int is_new)9829 bool rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
9830 			int is_new)
9831 {
9832 	struct mddev *mddev = rdev->mddev;
9833 
9834 	/*
9835 	 * Recording new badblocks for faulty rdev will force unnecessary
9836 	 * super block updating. This is fragile for external management because
9837 	 * userspace daemon may trying to remove this device and deadlock may
9838 	 * occur. This will be probably solved in the mdadm, but it is safer to
9839 	 * avoid it.
9840 	 */
9841 	if (test_bit(Faulty, &rdev->flags))
9842 		return true;
9843 
9844 	if (is_new)
9845 		s += rdev->new_data_offset;
9846 	else
9847 		s += rdev->data_offset;
9848 
9849 	if (!badblocks_set(&rdev->badblocks, s, sectors, 0))
9850 		return false;
9851 
9852 	/* Make sure they get written out promptly */
9853 	if (test_bit(ExternalBbl, &rdev->flags))
9854 		sysfs_notify_dirent_safe(rdev->sysfs_unack_badblocks);
9855 	sysfs_notify_dirent_safe(rdev->sysfs_state);
9856 	set_mask_bits(&mddev->sb_flags, 0,
9857 		      BIT(MD_SB_CHANGE_CLEAN) | BIT(MD_SB_CHANGE_PENDING));
9858 	md_wakeup_thread(rdev->mddev->thread);
9859 	return true;
9860 }
9861 EXPORT_SYMBOL_GPL(rdev_set_badblocks);
9862 
rdev_clear_badblocks(struct md_rdev * rdev,sector_t s,int sectors,int is_new)9863 void rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
9864 			  int is_new)
9865 {
9866 	if (is_new)
9867 		s += rdev->new_data_offset;
9868 	else
9869 		s += rdev->data_offset;
9870 
9871 	if (!badblocks_clear(&rdev->badblocks, s, sectors))
9872 		return;
9873 
9874 	if (test_bit(ExternalBbl, &rdev->flags))
9875 		sysfs_notify_dirent_safe(rdev->sysfs_badblocks);
9876 }
9877 EXPORT_SYMBOL_GPL(rdev_clear_badblocks);
9878 
md_notify_reboot(struct notifier_block * this,unsigned long code,void * x)9879 static int md_notify_reboot(struct notifier_block *this,
9880 			    unsigned long code, void *x)
9881 {
9882 	struct mddev *mddev;
9883 	int need_delay = 0;
9884 
9885 	spin_lock(&all_mddevs_lock);
9886 	list_for_each_entry(mddev, &all_mddevs, all_mddevs) {
9887 		if (!mddev_get(mddev))
9888 			continue;
9889 		spin_unlock(&all_mddevs_lock);
9890 		if (mddev_trylock(mddev)) {
9891 			if (mddev->pers)
9892 				__md_stop_writes(mddev);
9893 			if (mddev->persistent)
9894 				mddev->safemode = 2;
9895 			mddev_unlock(mddev);
9896 		}
9897 		need_delay = 1;
9898 		spin_lock(&all_mddevs_lock);
9899 		mddev_put_locked(mddev);
9900 	}
9901 	spin_unlock(&all_mddevs_lock);
9902 
9903 	/*
9904 	 * certain more exotic SCSI devices are known to be
9905 	 * volatile wrt too early system reboots. While the
9906 	 * right place to handle this issue is the given
9907 	 * driver, we do want to have a safe RAID driver ...
9908 	 */
9909 	if (need_delay)
9910 		msleep(1000);
9911 
9912 	return NOTIFY_DONE;
9913 }
9914 
9915 static struct notifier_block md_notifier = {
9916 	.notifier_call	= md_notify_reboot,
9917 	.next		= NULL,
9918 	.priority	= INT_MAX, /* before any real devices */
9919 };
9920 
md_geninit(void)9921 static void md_geninit(void)
9922 {
9923 	pr_debug("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
9924 
9925 	proc_create("mdstat", S_IRUGO, NULL, &mdstat_proc_ops);
9926 }
9927 
md_init(void)9928 static int __init md_init(void)
9929 {
9930 	int ret = -ENOMEM;
9931 
9932 	md_wq = alloc_workqueue("md", WQ_MEM_RECLAIM, 0);
9933 	if (!md_wq)
9934 		goto err_wq;
9935 
9936 	md_misc_wq = alloc_workqueue("md_misc", 0, 0);
9937 	if (!md_misc_wq)
9938 		goto err_misc_wq;
9939 
9940 	md_bitmap_wq = alloc_workqueue("md_bitmap", WQ_MEM_RECLAIM | WQ_UNBOUND,
9941 				       0);
9942 	if (!md_bitmap_wq)
9943 		goto err_bitmap_wq;
9944 
9945 	ret = __register_blkdev(MD_MAJOR, "md", md_probe);
9946 	if (ret < 0)
9947 		goto err_md;
9948 
9949 	ret = __register_blkdev(0, "mdp", md_probe);
9950 	if (ret < 0)
9951 		goto err_mdp;
9952 	mdp_major = ret;
9953 
9954 	register_reboot_notifier(&md_notifier);
9955 	raid_table_header = register_sysctl("dev/raid", raid_table);
9956 
9957 	md_geninit();
9958 	return 0;
9959 
9960 err_mdp:
9961 	unregister_blkdev(MD_MAJOR, "md");
9962 err_md:
9963 	destroy_workqueue(md_bitmap_wq);
9964 err_bitmap_wq:
9965 	destroy_workqueue(md_misc_wq);
9966 err_misc_wq:
9967 	destroy_workqueue(md_wq);
9968 err_wq:
9969 	return ret;
9970 }
9971 
check_sb_changes(struct mddev * mddev,struct md_rdev * rdev)9972 static void check_sb_changes(struct mddev *mddev, struct md_rdev *rdev)
9973 {
9974 	struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
9975 	struct md_rdev *rdev2, *tmp;
9976 	int role, ret;
9977 
9978 	/*
9979 	 * If size is changed in another node then we need to
9980 	 * do resize as well.
9981 	 */
9982 	if (mddev->dev_sectors != le64_to_cpu(sb->size)) {
9983 		ret = mddev->pers->resize(mddev, le64_to_cpu(sb->size));
9984 		if (ret)
9985 			pr_info("md-cluster: resize failed\n");
9986 		else
9987 			mddev->bitmap_ops->update_sb(mddev->bitmap);
9988 	}
9989 
9990 	/* Check for change of roles in the active devices */
9991 	rdev_for_each_safe(rdev2, tmp, mddev) {
9992 		if (test_bit(Faulty, &rdev2->flags))
9993 			continue;
9994 
9995 		/* Check if the roles changed */
9996 		role = le16_to_cpu(sb->dev_roles[rdev2->desc_nr]);
9997 
9998 		if (test_bit(Candidate, &rdev2->flags)) {
9999 			if (role == MD_DISK_ROLE_FAULTY) {
10000 				pr_info("md: Removing Candidate device %pg because add failed\n",
10001 					rdev2->bdev);
10002 				md_kick_rdev_from_array(rdev2);
10003 				continue;
10004 			}
10005 			else
10006 				clear_bit(Candidate, &rdev2->flags);
10007 		}
10008 
10009 		if (role != rdev2->raid_disk) {
10010 			/*
10011 			 * got activated except reshape is happening.
10012 			 */
10013 			if (rdev2->raid_disk == -1 && role != MD_DISK_ROLE_SPARE &&
10014 			    !(le32_to_cpu(sb->feature_map) &
10015 			      MD_FEATURE_RESHAPE_ACTIVE) &&
10016 			    !mddev->cluster_ops->resync_status_get(mddev)) {
10017 				/*
10018 				 * -1 to make raid1_add_disk() set conf->fullsync
10019 				 * to 1. This could avoid skipping sync when the
10020 				 * remote node is down during resyncing.
10021 				 */
10022 				if ((le32_to_cpu(sb->feature_map)
10023 				    & MD_FEATURE_RECOVERY_OFFSET))
10024 					rdev2->saved_raid_disk = -1;
10025 				else
10026 					rdev2->saved_raid_disk = role;
10027 				ret = remove_and_add_spares(mddev, rdev2);
10028 				pr_info("Activated spare: %pg\n",
10029 					rdev2->bdev);
10030 				/* wakeup mddev->thread here, so array could
10031 				 * perform resync with the new activated disk */
10032 				set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
10033 				md_wakeup_thread(mddev->thread);
10034 			}
10035 			/* device faulty
10036 			 * We just want to do the minimum to mark the disk
10037 			 * as faulty. The recovery is performed by the
10038 			 * one who initiated the error.
10039 			 */
10040 			if (role == MD_DISK_ROLE_FAULTY ||
10041 			    role == MD_DISK_ROLE_JOURNAL) {
10042 				md_error(mddev, rdev2);
10043 				clear_bit(Blocked, &rdev2->flags);
10044 			}
10045 		}
10046 	}
10047 
10048 	if (mddev->raid_disks != le32_to_cpu(sb->raid_disks)) {
10049 		ret = update_raid_disks(mddev, le32_to_cpu(sb->raid_disks));
10050 		if (ret)
10051 			pr_warn("md: updating array disks failed. %d\n", ret);
10052 	}
10053 
10054 	/*
10055 	 * Since mddev->delta_disks has already updated in update_raid_disks,
10056 	 * so it is time to check reshape.
10057 	 */
10058 	if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) &&
10059 	    (le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
10060 		/*
10061 		 * reshape is happening in the remote node, we need to
10062 		 * update reshape_position and call start_reshape.
10063 		 */
10064 		mddev->reshape_position = le64_to_cpu(sb->reshape_position);
10065 		if (mddev->pers->update_reshape_pos)
10066 			mddev->pers->update_reshape_pos(mddev);
10067 		if (mddev->pers->start_reshape)
10068 			mddev->pers->start_reshape(mddev);
10069 	} else if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) &&
10070 		   mddev->reshape_position != MaxSector &&
10071 		   !(le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
10072 		/* reshape is just done in another node. */
10073 		mddev->reshape_position = MaxSector;
10074 		if (mddev->pers->update_reshape_pos)
10075 			mddev->pers->update_reshape_pos(mddev);
10076 	}
10077 
10078 	/* Finally set the event to be up to date */
10079 	mddev->events = le64_to_cpu(sb->events);
10080 }
10081 
read_rdev(struct mddev * mddev,struct md_rdev * rdev)10082 static int read_rdev(struct mddev *mddev, struct md_rdev *rdev)
10083 {
10084 	int err;
10085 	struct page *swapout = rdev->sb_page;
10086 	struct mdp_superblock_1 *sb;
10087 
10088 	/* Store the sb page of the rdev in the swapout temporary
10089 	 * variable in case we err in the future
10090 	 */
10091 	rdev->sb_page = NULL;
10092 	err = alloc_disk_sb(rdev);
10093 	if (err == 0) {
10094 		ClearPageUptodate(rdev->sb_page);
10095 		rdev->sb_loaded = 0;
10096 		err = super_types[mddev->major_version].
10097 			load_super(rdev, NULL, mddev->minor_version);
10098 	}
10099 	if (err < 0) {
10100 		pr_warn("%s: %d Could not reload rdev(%d) err: %d. Restoring old values\n",
10101 				__func__, __LINE__, rdev->desc_nr, err);
10102 		if (rdev->sb_page)
10103 			put_page(rdev->sb_page);
10104 		rdev->sb_page = swapout;
10105 		rdev->sb_loaded = 1;
10106 		return err;
10107 	}
10108 
10109 	sb = page_address(rdev->sb_page);
10110 	/* Read the offset unconditionally, even if MD_FEATURE_RECOVERY_OFFSET
10111 	 * is not set
10112 	 */
10113 
10114 	if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RECOVERY_OFFSET))
10115 		rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
10116 
10117 	/* The other node finished recovery, call spare_active to set
10118 	 * device In_sync and mddev->degraded
10119 	 */
10120 	if (rdev->recovery_offset == MaxSector &&
10121 	    !test_bit(In_sync, &rdev->flags) &&
10122 	    mddev->pers->spare_active(mddev))
10123 		sysfs_notify_dirent_safe(mddev->sysfs_degraded);
10124 
10125 	put_page(swapout);
10126 	return 0;
10127 }
10128 
md_reload_sb(struct mddev * mddev,int nr)10129 void md_reload_sb(struct mddev *mddev, int nr)
10130 {
10131 	struct md_rdev *rdev = NULL, *iter;
10132 	int err;
10133 
10134 	/* Find the rdev */
10135 	rdev_for_each_rcu(iter, mddev) {
10136 		if (iter->desc_nr == nr) {
10137 			rdev = iter;
10138 			break;
10139 		}
10140 	}
10141 
10142 	if (!rdev) {
10143 		pr_warn("%s: %d Could not find rdev with nr %d\n", __func__, __LINE__, nr);
10144 		return;
10145 	}
10146 
10147 	err = read_rdev(mddev, rdev);
10148 	if (err < 0)
10149 		return;
10150 
10151 	check_sb_changes(mddev, rdev);
10152 
10153 	/* Read all rdev's to update recovery_offset */
10154 	rdev_for_each_rcu(rdev, mddev) {
10155 		if (!test_bit(Faulty, &rdev->flags))
10156 			read_rdev(mddev, rdev);
10157 	}
10158 }
10159 EXPORT_SYMBOL(md_reload_sb);
10160 
10161 #ifndef MODULE
10162 
10163 /*
10164  * Searches all registered partitions for autorun RAID arrays
10165  * at boot time.
10166  */
10167 
10168 static DEFINE_MUTEX(detected_devices_mutex);
10169 static LIST_HEAD(all_detected_devices);
10170 struct detected_devices_node {
10171 	struct list_head list;
10172 	dev_t dev;
10173 };
10174 
md_autodetect_dev(dev_t dev)10175 void md_autodetect_dev(dev_t dev)
10176 {
10177 	struct detected_devices_node *node_detected_dev;
10178 
10179 	node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL);
10180 	if (node_detected_dev) {
10181 		node_detected_dev->dev = dev;
10182 		mutex_lock(&detected_devices_mutex);
10183 		list_add_tail(&node_detected_dev->list, &all_detected_devices);
10184 		mutex_unlock(&detected_devices_mutex);
10185 	}
10186 }
10187 
md_autostart_arrays(int part)10188 void md_autostart_arrays(int part)
10189 {
10190 	struct md_rdev *rdev;
10191 	struct detected_devices_node *node_detected_dev;
10192 	dev_t dev;
10193 	int i_scanned, i_passed;
10194 
10195 	i_scanned = 0;
10196 	i_passed = 0;
10197 
10198 	pr_info("md: Autodetecting RAID arrays.\n");
10199 
10200 	mutex_lock(&detected_devices_mutex);
10201 	while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) {
10202 		i_scanned++;
10203 		node_detected_dev = list_entry(all_detected_devices.next,
10204 					struct detected_devices_node, list);
10205 		list_del(&node_detected_dev->list);
10206 		dev = node_detected_dev->dev;
10207 		kfree(node_detected_dev);
10208 		mutex_unlock(&detected_devices_mutex);
10209 		rdev = md_import_device(dev,0, 90);
10210 		mutex_lock(&detected_devices_mutex);
10211 		if (IS_ERR(rdev))
10212 			continue;
10213 
10214 		if (test_bit(Faulty, &rdev->flags))
10215 			continue;
10216 
10217 		set_bit(AutoDetected, &rdev->flags);
10218 		list_add(&rdev->same_set, &pending_raid_disks);
10219 		i_passed++;
10220 	}
10221 	mutex_unlock(&detected_devices_mutex);
10222 
10223 	pr_debug("md: Scanned %d and added %d devices.\n", i_scanned, i_passed);
10224 
10225 	autorun_devices(part);
10226 }
10227 
10228 #endif /* !MODULE */
10229 
md_exit(void)10230 static __exit void md_exit(void)
10231 {
10232 	struct mddev *mddev;
10233 	int delay = 1;
10234 
10235 	unregister_blkdev(MD_MAJOR,"md");
10236 	unregister_blkdev(mdp_major, "mdp");
10237 	unregister_reboot_notifier(&md_notifier);
10238 	unregister_sysctl_table(raid_table_header);
10239 
10240 	/* We cannot unload the modules while some process is
10241 	 * waiting for us in select() or poll() - wake them up
10242 	 */
10243 	md_unloading = 1;
10244 	while (waitqueue_active(&md_event_waiters)) {
10245 		/* not safe to leave yet */
10246 		wake_up(&md_event_waiters);
10247 		msleep(delay);
10248 		delay += delay;
10249 	}
10250 	remove_proc_entry("mdstat", NULL);
10251 
10252 	spin_lock(&all_mddevs_lock);
10253 	list_for_each_entry(mddev, &all_mddevs, all_mddevs) {
10254 		if (!mddev_get(mddev))
10255 			continue;
10256 		spin_unlock(&all_mddevs_lock);
10257 		export_array(mddev);
10258 		mddev->ctime = 0;
10259 		mddev->hold_active = 0;
10260 		/*
10261 		 * As the mddev is now fully clear, mddev_put will schedule
10262 		 * the mddev for destruction by a workqueue, and the
10263 		 * destroy_workqueue() below will wait for that to complete.
10264 		 */
10265 		spin_lock(&all_mddevs_lock);
10266 		mddev_put_locked(mddev);
10267 	}
10268 	spin_unlock(&all_mddevs_lock);
10269 
10270 	destroy_workqueue(md_misc_wq);
10271 	destroy_workqueue(md_bitmap_wq);
10272 	destroy_workqueue(md_wq);
10273 }
10274 
10275 subsys_initcall(md_init);
module_exit(md_exit)10276 module_exit(md_exit)
10277 
10278 static int get_ro(char *buffer, const struct kernel_param *kp)
10279 {
10280 	return sprintf(buffer, "%d\n", start_readonly);
10281 }
set_ro(const char * val,const struct kernel_param * kp)10282 static int set_ro(const char *val, const struct kernel_param *kp)
10283 {
10284 	return kstrtouint(val, 10, (unsigned int *)&start_readonly);
10285 }
10286 
10287 module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR);
10288 module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR);
10289 module_param_call(new_array, add_named_array, NULL, NULL, S_IWUSR);
10290 module_param(create_on_open, bool, S_IRUSR|S_IWUSR);
10291 
10292 MODULE_LICENSE("GPL");
10293 MODULE_DESCRIPTION("MD RAID framework");
10294 MODULE_ALIAS("md");
10295 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);
10296