selinux: fix overflow and 0 length allocations
[deliverable/linux.git] / drivers / md / md-cluster.c
1 /*
2 * Copyright (C) 2015, SUSE
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2, or (at your option)
7 * any later version.
8 *
9 */
10
11
12 #include <linux/module.h>
13 #include <linux/dlm.h>
14 #include <linux/sched.h>
15 #include <linux/raid/md_p.h>
16 #include "md.h"
17 #include "bitmap.h"
18 #include "md-cluster.h"
19
20 #define LVB_SIZE 64
21 #define NEW_DEV_TIMEOUT 5000
22
23 struct dlm_lock_resource {
24 dlm_lockspace_t *ls;
25 struct dlm_lksb lksb;
26 char *name; /* lock name. */
27 uint32_t flags; /* flags to pass to dlm_lock() */
28 struct completion completion; /* completion for synchronized locking */
29 void (*bast)(void *arg, int mode); /* blocking AST function pointer*/
30 struct mddev *mddev; /* pointing back to mddev. */
31 int mode;
32 };
33
34 struct suspend_info {
35 int slot;
36 sector_t lo;
37 sector_t hi;
38 struct list_head list;
39 };
40
41 struct resync_info {
42 __le64 lo;
43 __le64 hi;
44 };
45
46 /* md_cluster_info flags */
47 #define MD_CLUSTER_WAITING_FOR_NEWDISK 1
48 #define MD_CLUSTER_SUSPEND_READ_BALANCING 2
49 #define MD_CLUSTER_BEGIN_JOIN_CLUSTER 3
50
51 /* Lock the send communication. This is done through
52 * bit manipulation as opposed to a mutex in order to
53 * accomodate lock and hold. See next comment.
54 */
55 #define MD_CLUSTER_SEND_LOCK 4
56 /* If cluster operations (such as adding a disk) must lock the
57 * communication channel, so as to perform extra operations
58 * (update metadata) and no other operation is allowed on the
59 * MD. Token needs to be locked and held until the operation
60 * completes witha md_update_sb(), which would eventually release
61 * the lock.
62 */
63 #define MD_CLUSTER_SEND_LOCKED_ALREADY 5
64 /* We should receive message after node joined cluster and
65 * set up all the related infos such as bitmap and personality */
66 #define MD_CLUSTER_ALREADY_IN_CLUSTER 6
67 #define MD_CLUSTER_PENDING_RECV_EVENT 7
68
69
70 struct md_cluster_info {
71 /* dlm lock space and resources for clustered raid. */
72 dlm_lockspace_t *lockspace;
73 int slot_number;
74 struct completion completion;
75 struct mutex recv_mutex;
76 struct dlm_lock_resource *bitmap_lockres;
77 struct dlm_lock_resource **other_bitmap_lockres;
78 struct dlm_lock_resource *resync_lockres;
79 struct list_head suspend_list;
80 spinlock_t suspend_lock;
81 struct md_thread *recovery_thread;
82 unsigned long recovery_map;
83 /* communication loc resources */
84 struct dlm_lock_resource *ack_lockres;
85 struct dlm_lock_resource *message_lockres;
86 struct dlm_lock_resource *token_lockres;
87 struct dlm_lock_resource *no_new_dev_lockres;
88 struct md_thread *recv_thread;
89 struct completion newdisk_completion;
90 wait_queue_head_t wait;
91 unsigned long state;
92 /* record the region in RESYNCING message */
93 sector_t sync_low;
94 sector_t sync_hi;
95 };
96
97 enum msg_type {
98 METADATA_UPDATED = 0,
99 RESYNCING,
100 NEWDISK,
101 REMOVE,
102 RE_ADD,
103 BITMAP_NEEDS_SYNC,
104 };
105
106 struct cluster_msg {
107 __le32 type;
108 __le32 slot;
109 /* TODO: Unionize this for smaller footprint */
110 __le64 low;
111 __le64 high;
112 char uuid[16];
113 __le32 raid_slot;
114 };
115
116 static void sync_ast(void *arg)
117 {
118 struct dlm_lock_resource *res;
119
120 res = arg;
121 complete(&res->completion);
122 }
123
124 static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
125 {
126 int ret = 0;
127
128 ret = dlm_lock(res->ls, mode, &res->lksb,
129 res->flags, res->name, strlen(res->name),
130 0, sync_ast, res, res->bast);
131 if (ret)
132 return ret;
133 wait_for_completion(&res->completion);
134 if (res->lksb.sb_status == 0)
135 res->mode = mode;
136 return res->lksb.sb_status;
137 }
138
139 static int dlm_unlock_sync(struct dlm_lock_resource *res)
140 {
141 return dlm_lock_sync(res, DLM_LOCK_NL);
142 }
143
144 static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
145 char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
146 {
147 struct dlm_lock_resource *res = NULL;
148 int ret, namelen;
149 struct md_cluster_info *cinfo = mddev->cluster_info;
150
151 res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
152 if (!res)
153 return NULL;
154 init_completion(&res->completion);
155 res->ls = cinfo->lockspace;
156 res->mddev = mddev;
157 res->mode = DLM_LOCK_IV;
158 namelen = strlen(name);
159 res->name = kzalloc(namelen + 1, GFP_KERNEL);
160 if (!res->name) {
161 pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
162 goto out_err;
163 }
164 strlcpy(res->name, name, namelen + 1);
165 if (with_lvb) {
166 res->lksb.sb_lvbptr = kzalloc(LVB_SIZE, GFP_KERNEL);
167 if (!res->lksb.sb_lvbptr) {
168 pr_err("md-cluster: Unable to allocate LVB for resource %s\n", name);
169 goto out_err;
170 }
171 res->flags = DLM_LKF_VALBLK;
172 }
173
174 if (bastfn)
175 res->bast = bastfn;
176
177 res->flags |= DLM_LKF_EXPEDITE;
178
179 ret = dlm_lock_sync(res, DLM_LOCK_NL);
180 if (ret) {
181 pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
182 goto out_err;
183 }
184 res->flags &= ~DLM_LKF_EXPEDITE;
185 res->flags |= DLM_LKF_CONVERT;
186
187 return res;
188 out_err:
189 kfree(res->lksb.sb_lvbptr);
190 kfree(res->name);
191 kfree(res);
192 return NULL;
193 }
194
195 static void lockres_free(struct dlm_lock_resource *res)
196 {
197 int ret;
198
199 if (!res)
200 return;
201
202 /* cancel a lock request or a conversion request that is blocked */
203 res->flags |= DLM_LKF_CANCEL;
204 retry:
205 ret = dlm_unlock(res->ls, res->lksb.sb_lkid, 0, &res->lksb, res);
206 if (unlikely(ret != 0)) {
207 pr_info("%s: failed to unlock %s return %d\n", __func__, res->name, ret);
208
209 /* if a lock conversion is cancelled, then the lock is put
210 * back to grant queue, need to ensure it is unlocked */
211 if (ret == -DLM_ECANCEL)
212 goto retry;
213 }
214 res->flags &= ~DLM_LKF_CANCEL;
215 wait_for_completion(&res->completion);
216
217 kfree(res->name);
218 kfree(res->lksb.sb_lvbptr);
219 kfree(res);
220 }
221
222 static void add_resync_info(struct dlm_lock_resource *lockres,
223 sector_t lo, sector_t hi)
224 {
225 struct resync_info *ri;
226
227 ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
228 ri->lo = cpu_to_le64(lo);
229 ri->hi = cpu_to_le64(hi);
230 }
231
232 static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
233 {
234 struct resync_info ri;
235 struct suspend_info *s = NULL;
236 sector_t hi = 0;
237
238 dlm_lock_sync(lockres, DLM_LOCK_CR);
239 memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
240 hi = le64_to_cpu(ri.hi);
241 if (hi > 0) {
242 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
243 if (!s)
244 goto out;
245 s->hi = hi;
246 s->lo = le64_to_cpu(ri.lo);
247 }
248 dlm_unlock_sync(lockres);
249 out:
250 return s;
251 }
252
253 static void recover_bitmaps(struct md_thread *thread)
254 {
255 struct mddev *mddev = thread->mddev;
256 struct md_cluster_info *cinfo = mddev->cluster_info;
257 struct dlm_lock_resource *bm_lockres;
258 char str[64];
259 int slot, ret;
260 struct suspend_info *s, *tmp;
261 sector_t lo, hi;
262
263 while (cinfo->recovery_map) {
264 slot = fls64((u64)cinfo->recovery_map) - 1;
265
266 /* Clear suspend_area associated with the bitmap */
267 spin_lock_irq(&cinfo->suspend_lock);
268 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
269 if (slot == s->slot) {
270 list_del(&s->list);
271 kfree(s);
272 }
273 spin_unlock_irq(&cinfo->suspend_lock);
274
275 snprintf(str, 64, "bitmap%04d", slot);
276 bm_lockres = lockres_init(mddev, str, NULL, 1);
277 if (!bm_lockres) {
278 pr_err("md-cluster: Cannot initialize bitmaps\n");
279 goto clear_bit;
280 }
281
282 ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
283 if (ret) {
284 pr_err("md-cluster: Could not DLM lock %s: %d\n",
285 str, ret);
286 goto clear_bit;
287 }
288 ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
289 if (ret) {
290 pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
291 goto dlm_unlock;
292 }
293 if (hi > 0) {
294 if (lo < mddev->recovery_cp)
295 mddev->recovery_cp = lo;
296 /* wake up thread to continue resync in case resync
297 * is not finished */
298 if (mddev->recovery_cp != MaxSector) {
299 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
300 md_wakeup_thread(mddev->thread);
301 }
302 }
303 dlm_unlock:
304 dlm_unlock_sync(bm_lockres);
305 clear_bit:
306 lockres_free(bm_lockres);
307 clear_bit(slot, &cinfo->recovery_map);
308 }
309 }
310
311 static void recover_prep(void *arg)
312 {
313 struct mddev *mddev = arg;
314 struct md_cluster_info *cinfo = mddev->cluster_info;
315 set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
316 }
317
318 static void __recover_slot(struct mddev *mddev, int slot)
319 {
320 struct md_cluster_info *cinfo = mddev->cluster_info;
321
322 set_bit(slot, &cinfo->recovery_map);
323 if (!cinfo->recovery_thread) {
324 cinfo->recovery_thread = md_register_thread(recover_bitmaps,
325 mddev, "recover");
326 if (!cinfo->recovery_thread) {
327 pr_warn("md-cluster: Could not create recovery thread\n");
328 return;
329 }
330 }
331 md_wakeup_thread(cinfo->recovery_thread);
332 }
333
334 static void recover_slot(void *arg, struct dlm_slot *slot)
335 {
336 struct mddev *mddev = arg;
337 struct md_cluster_info *cinfo = mddev->cluster_info;
338
339 pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
340 mddev->bitmap_info.cluster_name,
341 slot->nodeid, slot->slot,
342 cinfo->slot_number);
343 /* deduct one since dlm slot starts from one while the num of
344 * cluster-md begins with 0 */
345 __recover_slot(mddev, slot->slot - 1);
346 }
347
348 static void recover_done(void *arg, struct dlm_slot *slots,
349 int num_slots, int our_slot,
350 uint32_t generation)
351 {
352 struct mddev *mddev = arg;
353 struct md_cluster_info *cinfo = mddev->cluster_info;
354
355 cinfo->slot_number = our_slot;
356 /* completion is only need to be complete when node join cluster,
357 * it doesn't need to run during another node's failure */
358 if (test_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state)) {
359 complete(&cinfo->completion);
360 clear_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
361 }
362 clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
363 }
364
365 /* the ops is called when node join the cluster, and do lock recovery
366 * if node failure occurs */
367 static const struct dlm_lockspace_ops md_ls_ops = {
368 .recover_prep = recover_prep,
369 .recover_slot = recover_slot,
370 .recover_done = recover_done,
371 };
372
373 /*
374 * The BAST function for the ack lock resource
375 * This function wakes up the receive thread in
376 * order to receive and process the message.
377 */
378 static void ack_bast(void *arg, int mode)
379 {
380 struct dlm_lock_resource *res = arg;
381 struct md_cluster_info *cinfo = res->mddev->cluster_info;
382
383 if (mode == DLM_LOCK_EX) {
384 if (test_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state))
385 md_wakeup_thread(cinfo->recv_thread);
386 else
387 set_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state);
388 }
389 }
390
391 static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
392 {
393 struct suspend_info *s, *tmp;
394
395 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
396 if (slot == s->slot) {
397 list_del(&s->list);
398 kfree(s);
399 break;
400 }
401 }
402
403 static void remove_suspend_info(struct mddev *mddev, int slot)
404 {
405 struct md_cluster_info *cinfo = mddev->cluster_info;
406 spin_lock_irq(&cinfo->suspend_lock);
407 __remove_suspend_info(cinfo, slot);
408 spin_unlock_irq(&cinfo->suspend_lock);
409 mddev->pers->quiesce(mddev, 2);
410 }
411
412
413 static void process_suspend_info(struct mddev *mddev,
414 int slot, sector_t lo, sector_t hi)
415 {
416 struct md_cluster_info *cinfo = mddev->cluster_info;
417 struct suspend_info *s;
418
419 if (!hi) {
420 remove_suspend_info(mddev, slot);
421 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
422 md_wakeup_thread(mddev->thread);
423 return;
424 }
425
426 /*
427 * The bitmaps are not same for different nodes
428 * if RESYNCING is happening in one node, then
429 * the node which received the RESYNCING message
430 * probably will perform resync with the region
431 * [lo, hi] again, so we could reduce resync time
432 * a lot if we can ensure that the bitmaps among
433 * different nodes are match up well.
434 *
435 * sync_low/hi is used to record the region which
436 * arrived in the previous RESYNCING message,
437 *
438 * Call bitmap_sync_with_cluster to clear
439 * NEEDED_MASK and set RESYNC_MASK since
440 * resync thread is running in another node,
441 * so we don't need to do the resync again
442 * with the same section */
443 bitmap_sync_with_cluster(mddev, cinfo->sync_low,
444 cinfo->sync_hi,
445 lo, hi);
446 cinfo->sync_low = lo;
447 cinfo->sync_hi = hi;
448
449 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
450 if (!s)
451 return;
452 s->slot = slot;
453 s->lo = lo;
454 s->hi = hi;
455 mddev->pers->quiesce(mddev, 1);
456 mddev->pers->quiesce(mddev, 0);
457 spin_lock_irq(&cinfo->suspend_lock);
458 /* Remove existing entry (if exists) before adding */
459 __remove_suspend_info(cinfo, slot);
460 list_add(&s->list, &cinfo->suspend_list);
461 spin_unlock_irq(&cinfo->suspend_lock);
462 mddev->pers->quiesce(mddev, 2);
463 }
464
465 static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
466 {
467 char disk_uuid[64];
468 struct md_cluster_info *cinfo = mddev->cluster_info;
469 char event_name[] = "EVENT=ADD_DEVICE";
470 char raid_slot[16];
471 char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
472 int len;
473
474 len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
475 sprintf(disk_uuid + len, "%pU", cmsg->uuid);
476 snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
477 pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
478 init_completion(&cinfo->newdisk_completion);
479 set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
480 kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
481 wait_for_completion_timeout(&cinfo->newdisk_completion,
482 NEW_DEV_TIMEOUT);
483 clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
484 }
485
486
487 static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
488 {
489 struct md_cluster_info *cinfo = mddev->cluster_info;
490 mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
491 set_bit(MD_RELOAD_SB, &mddev->flags);
492 dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
493 md_wakeup_thread(mddev->thread);
494 }
495
496 static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
497 {
498 struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev,
499 le32_to_cpu(msg->raid_slot));
500
501 if (rdev) {
502 set_bit(ClusterRemove, &rdev->flags);
503 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
504 md_wakeup_thread(mddev->thread);
505 }
506 else
507 pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
508 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
509 }
510
511 static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
512 {
513 struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev,
514 le32_to_cpu(msg->raid_slot));
515
516 if (rdev && test_bit(Faulty, &rdev->flags))
517 clear_bit(Faulty, &rdev->flags);
518 else
519 pr_warn("%s: %d Could not find disk(%d) which is faulty",
520 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
521 }
522
523 static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
524 {
525 int ret = 0;
526
527 if (WARN(mddev->cluster_info->slot_number - 1 == le32_to_cpu(msg->slot),
528 "node %d received it's own msg\n", le32_to_cpu(msg->slot)))
529 return -1;
530 switch (le32_to_cpu(msg->type)) {
531 case METADATA_UPDATED:
532 process_metadata_update(mddev, msg);
533 break;
534 case RESYNCING:
535 process_suspend_info(mddev, le32_to_cpu(msg->slot),
536 le64_to_cpu(msg->low),
537 le64_to_cpu(msg->high));
538 break;
539 case NEWDISK:
540 process_add_new_disk(mddev, msg);
541 break;
542 case REMOVE:
543 process_remove_disk(mddev, msg);
544 break;
545 case RE_ADD:
546 process_readd_disk(mddev, msg);
547 break;
548 case BITMAP_NEEDS_SYNC:
549 __recover_slot(mddev, le32_to_cpu(msg->slot));
550 break;
551 default:
552 ret = -1;
553 pr_warn("%s:%d Received unknown message from %d\n",
554 __func__, __LINE__, msg->slot);
555 }
556 return ret;
557 }
558
559 /*
560 * thread for receiving message
561 */
562 static void recv_daemon(struct md_thread *thread)
563 {
564 struct md_cluster_info *cinfo = thread->mddev->cluster_info;
565 struct dlm_lock_resource *ack_lockres = cinfo->ack_lockres;
566 struct dlm_lock_resource *message_lockres = cinfo->message_lockres;
567 struct cluster_msg msg;
568 int ret;
569
570 mutex_lock(&cinfo->recv_mutex);
571 /*get CR on Message*/
572 if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) {
573 pr_err("md/raid1:failed to get CR on MESSAGE\n");
574 mutex_unlock(&cinfo->recv_mutex);
575 return;
576 }
577
578 /* read lvb and wake up thread to process this message_lockres */
579 memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg));
580 ret = process_recvd_msg(thread->mddev, &msg);
581 if (ret)
582 goto out;
583
584 /*release CR on ack_lockres*/
585 ret = dlm_unlock_sync(ack_lockres);
586 if (unlikely(ret != 0))
587 pr_info("unlock ack failed return %d\n", ret);
588 /*up-convert to PR on message_lockres*/
589 ret = dlm_lock_sync(message_lockres, DLM_LOCK_PR);
590 if (unlikely(ret != 0))
591 pr_info("lock PR on msg failed return %d\n", ret);
592 /*get CR on ack_lockres again*/
593 ret = dlm_lock_sync(ack_lockres, DLM_LOCK_CR);
594 if (unlikely(ret != 0))
595 pr_info("lock CR on ack failed return %d\n", ret);
596 out:
597 /*release CR on message_lockres*/
598 ret = dlm_unlock_sync(message_lockres);
599 if (unlikely(ret != 0))
600 pr_info("unlock msg failed return %d\n", ret);
601 mutex_unlock(&cinfo->recv_mutex);
602 }
603
604 /* lock_token()
605 * Takes the lock on the TOKEN lock resource so no other
606 * node can communicate while the operation is underway.
607 */
608 static int lock_token(struct md_cluster_info *cinfo)
609 {
610 int error;
611
612 error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
613 if (error)
614 pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
615 __func__, __LINE__, error);
616
617 /* Lock the receive sequence */
618 mutex_lock(&cinfo->recv_mutex);
619 return error;
620 }
621
622 /* lock_comm()
623 * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
624 */
625 static int lock_comm(struct md_cluster_info *cinfo)
626 {
627 wait_event(cinfo->wait,
628 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
629
630 return lock_token(cinfo);
631 }
632
633 static void unlock_comm(struct md_cluster_info *cinfo)
634 {
635 WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
636 mutex_unlock(&cinfo->recv_mutex);
637 dlm_unlock_sync(cinfo->token_lockres);
638 clear_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state);
639 wake_up(&cinfo->wait);
640 }
641
642 /* __sendmsg()
643 * This function performs the actual sending of the message. This function is
644 * usually called after performing the encompassing operation
645 * The function:
646 * 1. Grabs the message lockresource in EX mode
647 * 2. Copies the message to the message LVB
648 * 3. Downconverts message lockresource to CW
649 * 4. Upconverts ack lock resource from CR to EX. This forces the BAST on other nodes
650 * and the other nodes read the message. The thread will wait here until all other
651 * nodes have released ack lock resource.
652 * 5. Downconvert ack lockresource to CR
653 */
654 static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
655 {
656 int error;
657 int slot = cinfo->slot_number - 1;
658
659 cmsg->slot = cpu_to_le32(slot);
660 /*get EX on Message*/
661 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
662 if (error) {
663 pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
664 goto failed_message;
665 }
666
667 memcpy(cinfo->message_lockres->lksb.sb_lvbptr, (void *)cmsg,
668 sizeof(struct cluster_msg));
669 /*down-convert EX to CW on Message*/
670 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CW);
671 if (error) {
672 pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
673 error);
674 goto failed_ack;
675 }
676
677 /*up-convert CR to EX on Ack*/
678 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
679 if (error) {
680 pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
681 error);
682 goto failed_ack;
683 }
684
685 /*down-convert EX to CR on Ack*/
686 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
687 if (error) {
688 pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
689 error);
690 goto failed_ack;
691 }
692
693 failed_ack:
694 error = dlm_unlock_sync(cinfo->message_lockres);
695 if (unlikely(error != 0)) {
696 pr_err("md-cluster: failed convert to NL on MESSAGE(%d)\n",
697 error);
698 /* in case the message can't be released due to some reason */
699 goto failed_ack;
700 }
701 failed_message:
702 return error;
703 }
704
705 static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
706 {
707 int ret;
708
709 lock_comm(cinfo);
710 ret = __sendmsg(cinfo, cmsg);
711 unlock_comm(cinfo);
712 return ret;
713 }
714
715 static int gather_all_resync_info(struct mddev *mddev, int total_slots)
716 {
717 struct md_cluster_info *cinfo = mddev->cluster_info;
718 int i, ret = 0;
719 struct dlm_lock_resource *bm_lockres;
720 struct suspend_info *s;
721 char str[64];
722 sector_t lo, hi;
723
724
725 for (i = 0; i < total_slots; i++) {
726 memset(str, '\0', 64);
727 snprintf(str, 64, "bitmap%04d", i);
728 bm_lockres = lockres_init(mddev, str, NULL, 1);
729 if (!bm_lockres)
730 return -ENOMEM;
731 if (i == (cinfo->slot_number - 1)) {
732 lockres_free(bm_lockres);
733 continue;
734 }
735
736 bm_lockres->flags |= DLM_LKF_NOQUEUE;
737 ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
738 if (ret == -EAGAIN) {
739 memset(bm_lockres->lksb.sb_lvbptr, '\0', LVB_SIZE);
740 s = read_resync_info(mddev, bm_lockres);
741 if (s) {
742 pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
743 __func__, __LINE__,
744 (unsigned long long) s->lo,
745 (unsigned long long) s->hi, i);
746 spin_lock_irq(&cinfo->suspend_lock);
747 s->slot = i;
748 list_add(&s->list, &cinfo->suspend_list);
749 spin_unlock_irq(&cinfo->suspend_lock);
750 }
751 ret = 0;
752 lockres_free(bm_lockres);
753 continue;
754 }
755 if (ret) {
756 lockres_free(bm_lockres);
757 goto out;
758 }
759
760 /* Read the disk bitmap sb and check if it needs recovery */
761 ret = bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
762 if (ret) {
763 pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
764 lockres_free(bm_lockres);
765 continue;
766 }
767 if ((hi > 0) && (lo < mddev->recovery_cp)) {
768 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
769 mddev->recovery_cp = lo;
770 md_check_recovery(mddev);
771 }
772
773 dlm_unlock_sync(bm_lockres);
774 lockres_free(bm_lockres);
775 }
776 out:
777 return ret;
778 }
779
780 static int join(struct mddev *mddev, int nodes)
781 {
782 struct md_cluster_info *cinfo;
783 int ret, ops_rv;
784 char str[64];
785
786 cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
787 if (!cinfo)
788 return -ENOMEM;
789
790 INIT_LIST_HEAD(&cinfo->suspend_list);
791 spin_lock_init(&cinfo->suspend_lock);
792 init_completion(&cinfo->completion);
793 set_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
794 init_waitqueue_head(&cinfo->wait);
795 mutex_init(&cinfo->recv_mutex);
796
797 mddev->cluster_info = cinfo;
798
799 memset(str, 0, 64);
800 sprintf(str, "%pU", mddev->uuid);
801 ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
802 DLM_LSFL_FS, LVB_SIZE,
803 &md_ls_ops, mddev, &ops_rv, &cinfo->lockspace);
804 if (ret)
805 goto err;
806 wait_for_completion(&cinfo->completion);
807 if (nodes < cinfo->slot_number) {
808 pr_err("md-cluster: Slot allotted(%d) is greater than available slots(%d).",
809 cinfo->slot_number, nodes);
810 ret = -ERANGE;
811 goto err;
812 }
813 /* Initiate the communication resources */
814 ret = -ENOMEM;
815 cinfo->recv_thread = md_register_thread(recv_daemon, mddev, "cluster_recv");
816 if (!cinfo->recv_thread) {
817 pr_err("md-cluster: cannot allocate memory for recv_thread!\n");
818 goto err;
819 }
820 cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
821 if (!cinfo->message_lockres)
822 goto err;
823 cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
824 if (!cinfo->token_lockres)
825 goto err;
826 cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
827 if (!cinfo->no_new_dev_lockres)
828 goto err;
829
830 ret = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
831 if (ret) {
832 ret = -EAGAIN;
833 pr_err("md-cluster: can't join cluster to avoid lock issue\n");
834 goto err;
835 }
836 cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
837 if (!cinfo->ack_lockres)
838 goto err;
839 /* get sync CR lock on ACK. */
840 if (dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR))
841 pr_err("md-cluster: failed to get a sync CR lock on ACK!(%d)\n",
842 ret);
843 dlm_unlock_sync(cinfo->token_lockres);
844 /* get sync CR lock on no-new-dev. */
845 if (dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR))
846 pr_err("md-cluster: failed to get a sync CR lock on no-new-dev!(%d)\n", ret);
847
848
849 pr_info("md-cluster: Joined cluster %s slot %d\n", str, cinfo->slot_number);
850 snprintf(str, 64, "bitmap%04d", cinfo->slot_number - 1);
851 cinfo->bitmap_lockres = lockres_init(mddev, str, NULL, 1);
852 if (!cinfo->bitmap_lockres)
853 goto err;
854 if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
855 pr_err("Failed to get bitmap lock\n");
856 ret = -EINVAL;
857 goto err;
858 }
859
860 cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
861 if (!cinfo->resync_lockres)
862 goto err;
863
864 return 0;
865 err:
866 md_unregister_thread(&cinfo->recovery_thread);
867 md_unregister_thread(&cinfo->recv_thread);
868 lockres_free(cinfo->message_lockres);
869 lockres_free(cinfo->token_lockres);
870 lockres_free(cinfo->ack_lockres);
871 lockres_free(cinfo->no_new_dev_lockres);
872 lockres_free(cinfo->resync_lockres);
873 lockres_free(cinfo->bitmap_lockres);
874 if (cinfo->lockspace)
875 dlm_release_lockspace(cinfo->lockspace, 2);
876 mddev->cluster_info = NULL;
877 kfree(cinfo);
878 return ret;
879 }
880
881 static void load_bitmaps(struct mddev *mddev, int total_slots)
882 {
883 struct md_cluster_info *cinfo = mddev->cluster_info;
884
885 /* load all the node's bitmap info for resync */
886 if (gather_all_resync_info(mddev, total_slots))
887 pr_err("md-cluster: failed to gather all resyn infos\n");
888 set_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state);
889 /* wake up recv thread in case something need to be handled */
890 if (test_and_clear_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state))
891 md_wakeup_thread(cinfo->recv_thread);
892 }
893
894 static void resync_bitmap(struct mddev *mddev)
895 {
896 struct md_cluster_info *cinfo = mddev->cluster_info;
897 struct cluster_msg cmsg = {0};
898 int err;
899
900 cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
901 err = sendmsg(cinfo, &cmsg);
902 if (err)
903 pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
904 __func__, __LINE__, err);
905 }
906
907 static void unlock_all_bitmaps(struct mddev *mddev);
908 static int leave(struct mddev *mddev)
909 {
910 struct md_cluster_info *cinfo = mddev->cluster_info;
911
912 if (!cinfo)
913 return 0;
914
915 /* BITMAP_NEEDS_SYNC message should be sent when node
916 * is leaving the cluster with dirty bitmap, also we
917 * can only deliver it when dlm connection is available */
918 if (cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector)
919 resync_bitmap(mddev);
920
921 md_unregister_thread(&cinfo->recovery_thread);
922 md_unregister_thread(&cinfo->recv_thread);
923 lockres_free(cinfo->message_lockres);
924 lockres_free(cinfo->token_lockres);
925 lockres_free(cinfo->ack_lockres);
926 lockres_free(cinfo->no_new_dev_lockres);
927 lockres_free(cinfo->resync_lockres);
928 lockres_free(cinfo->bitmap_lockres);
929 unlock_all_bitmaps(mddev);
930 dlm_release_lockspace(cinfo->lockspace, 2);
931 return 0;
932 }
933
934 /* slot_number(): Returns the MD slot number to use
935 * DLM starts the slot numbers from 1, wheras cluster-md
936 * wants the number to be from zero, so we deduct one
937 */
938 static int slot_number(struct mddev *mddev)
939 {
940 struct md_cluster_info *cinfo = mddev->cluster_info;
941
942 return cinfo->slot_number - 1;
943 }
944
945 /*
946 * Check if the communication is already locked, else lock the communication
947 * channel.
948 * If it is already locked, token is in EX mode, and hence lock_token()
949 * should not be called.
950 */
951 static int metadata_update_start(struct mddev *mddev)
952 {
953 struct md_cluster_info *cinfo = mddev->cluster_info;
954
955 wait_event(cinfo->wait,
956 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state) ||
957 test_and_clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state));
958
959 /* If token is already locked, return 0 */
960 if (cinfo->token_lockres->mode == DLM_LOCK_EX)
961 return 0;
962
963 return lock_token(cinfo);
964 }
965
966 static int metadata_update_finish(struct mddev *mddev)
967 {
968 struct md_cluster_info *cinfo = mddev->cluster_info;
969 struct cluster_msg cmsg;
970 struct md_rdev *rdev;
971 int ret = 0;
972 int raid_slot = -1;
973
974 memset(&cmsg, 0, sizeof(cmsg));
975 cmsg.type = cpu_to_le32(METADATA_UPDATED);
976 /* Pick up a good active device number to send.
977 */
978 rdev_for_each(rdev, mddev)
979 if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
980 raid_slot = rdev->desc_nr;
981 break;
982 }
983 if (raid_slot >= 0) {
984 cmsg.raid_slot = cpu_to_le32(raid_slot);
985 ret = __sendmsg(cinfo, &cmsg);
986 } else
987 pr_warn("md-cluster: No good device id found to send\n");
988 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
989 unlock_comm(cinfo);
990 return ret;
991 }
992
993 static void metadata_update_cancel(struct mddev *mddev)
994 {
995 struct md_cluster_info *cinfo = mddev->cluster_info;
996 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
997 unlock_comm(cinfo);
998 }
999
1000 static int resync_start(struct mddev *mddev)
1001 {
1002 struct md_cluster_info *cinfo = mddev->cluster_info;
1003 return dlm_lock_sync(cinfo->resync_lockres, DLM_LOCK_EX);
1004 }
1005
1006 static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
1007 {
1008 struct md_cluster_info *cinfo = mddev->cluster_info;
1009 struct resync_info ri;
1010 struct cluster_msg cmsg = {0};
1011
1012 /* do not send zero again, if we have sent before */
1013 if (hi == 0) {
1014 memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
1015 if (le64_to_cpu(ri.hi) == 0)
1016 return 0;
1017 }
1018
1019 add_resync_info(cinfo->bitmap_lockres, lo, hi);
1020 /* Re-acquire the lock to refresh LVB */
1021 dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
1022 cmsg.type = cpu_to_le32(RESYNCING);
1023 cmsg.low = cpu_to_le64(lo);
1024 cmsg.high = cpu_to_le64(hi);
1025
1026 return sendmsg(cinfo, &cmsg);
1027 }
1028
1029 static int resync_finish(struct mddev *mddev)
1030 {
1031 struct md_cluster_info *cinfo = mddev->cluster_info;
1032 dlm_unlock_sync(cinfo->resync_lockres);
1033 return resync_info_update(mddev, 0, 0);
1034 }
1035
1036 static int area_resyncing(struct mddev *mddev, int direction,
1037 sector_t lo, sector_t hi)
1038 {
1039 struct md_cluster_info *cinfo = mddev->cluster_info;
1040 int ret = 0;
1041 struct suspend_info *s;
1042
1043 if ((direction == READ) &&
1044 test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
1045 return 1;
1046
1047 spin_lock_irq(&cinfo->suspend_lock);
1048 if (list_empty(&cinfo->suspend_list))
1049 goto out;
1050 list_for_each_entry(s, &cinfo->suspend_list, list)
1051 if (hi > s->lo && lo < s->hi) {
1052 ret = 1;
1053 break;
1054 }
1055 out:
1056 spin_unlock_irq(&cinfo->suspend_lock);
1057 return ret;
1058 }
1059
1060 /* add_new_disk() - initiates a disk add
1061 * However, if this fails before writing md_update_sb(),
1062 * add_new_disk_cancel() must be called to release token lock
1063 */
1064 static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
1065 {
1066 struct md_cluster_info *cinfo = mddev->cluster_info;
1067 struct cluster_msg cmsg;
1068 int ret = 0;
1069 struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1070 char *uuid = sb->device_uuid;
1071
1072 memset(&cmsg, 0, sizeof(cmsg));
1073 cmsg.type = cpu_to_le32(NEWDISK);
1074 memcpy(cmsg.uuid, uuid, 16);
1075 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1076 lock_comm(cinfo);
1077 ret = __sendmsg(cinfo, &cmsg);
1078 if (ret)
1079 return ret;
1080 cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
1081 ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
1082 cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;
1083 /* Some node does not "see" the device */
1084 if (ret == -EAGAIN)
1085 ret = -ENOENT;
1086 if (ret)
1087 unlock_comm(cinfo);
1088 else {
1089 dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
1090 /* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
1091 * will run soon after add_new_disk, the below path will be
1092 * invoked:
1093 * md_wakeup_thread(mddev->thread)
1094 * -> conf->thread (raid1d)
1095 * -> md_check_recovery -> md_update_sb
1096 * -> metadata_update_start/finish
1097 * MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
1098 *
1099 * For other failure cases, metadata_update_cancel and
1100 * add_new_disk_cancel also clear below bit as well.
1101 * */
1102 set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1103 wake_up(&cinfo->wait);
1104 }
1105 return ret;
1106 }
1107
1108 static void add_new_disk_cancel(struct mddev *mddev)
1109 {
1110 struct md_cluster_info *cinfo = mddev->cluster_info;
1111 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1112 unlock_comm(cinfo);
1113 }
1114
1115 static int new_disk_ack(struct mddev *mddev, bool ack)
1116 {
1117 struct md_cluster_info *cinfo = mddev->cluster_info;
1118
1119 if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
1120 pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
1121 return -EINVAL;
1122 }
1123
1124 if (ack)
1125 dlm_unlock_sync(cinfo->no_new_dev_lockres);
1126 complete(&cinfo->newdisk_completion);
1127 return 0;
1128 }
1129
1130 static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1131 {
1132 struct cluster_msg cmsg = {0};
1133 struct md_cluster_info *cinfo = mddev->cluster_info;
1134 cmsg.type = cpu_to_le32(REMOVE);
1135 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1136 return sendmsg(cinfo, &cmsg);
1137 }
1138
1139 static int lock_all_bitmaps(struct mddev *mddev)
1140 {
1141 int slot, my_slot, ret, held = 1, i = 0;
1142 char str[64];
1143 struct md_cluster_info *cinfo = mddev->cluster_info;
1144
1145 cinfo->other_bitmap_lockres = kzalloc((mddev->bitmap_info.nodes - 1) *
1146 sizeof(struct dlm_lock_resource *),
1147 GFP_KERNEL);
1148 if (!cinfo->other_bitmap_lockres) {
1149 pr_err("md: can't alloc mem for other bitmap locks\n");
1150 return 0;
1151 }
1152
1153 my_slot = slot_number(mddev);
1154 for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
1155 if (slot == my_slot)
1156 continue;
1157
1158 memset(str, '\0', 64);
1159 snprintf(str, 64, "bitmap%04d", slot);
1160 cinfo->other_bitmap_lockres[i] = lockres_init(mddev, str, NULL, 1);
1161 if (!cinfo->other_bitmap_lockres[i])
1162 return -ENOMEM;
1163
1164 cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
1165 ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
1166 if (ret)
1167 held = -1;
1168 i++;
1169 }
1170
1171 return held;
1172 }
1173
1174 static void unlock_all_bitmaps(struct mddev *mddev)
1175 {
1176 struct md_cluster_info *cinfo = mddev->cluster_info;
1177 int i;
1178
1179 /* release other node's bitmap lock if they are existed */
1180 if (cinfo->other_bitmap_lockres) {
1181 for (i = 0; i < mddev->bitmap_info.nodes - 1; i++) {
1182 if (cinfo->other_bitmap_lockres[i]) {
1183 dlm_unlock_sync(cinfo->other_bitmap_lockres[i]);
1184 lockres_free(cinfo->other_bitmap_lockres[i]);
1185 }
1186 }
1187 kfree(cinfo->other_bitmap_lockres);
1188 }
1189 }
1190
1191 static int gather_bitmaps(struct md_rdev *rdev)
1192 {
1193 int sn, err;
1194 sector_t lo, hi;
1195 struct cluster_msg cmsg = {0};
1196 struct mddev *mddev = rdev->mddev;
1197 struct md_cluster_info *cinfo = mddev->cluster_info;
1198
1199 cmsg.type = cpu_to_le32(RE_ADD);
1200 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1201 err = sendmsg(cinfo, &cmsg);
1202 if (err)
1203 goto out;
1204
1205 for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
1206 if (sn == (cinfo->slot_number - 1))
1207 continue;
1208 err = bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
1209 if (err) {
1210 pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
1211 goto out;
1212 }
1213 if ((hi > 0) && (lo < mddev->recovery_cp))
1214 mddev->recovery_cp = lo;
1215 }
1216 out:
1217 return err;
1218 }
1219
1220 static struct md_cluster_operations cluster_ops = {
1221 .join = join,
1222 .leave = leave,
1223 .slot_number = slot_number,
1224 .resync_start = resync_start,
1225 .resync_finish = resync_finish,
1226 .resync_info_update = resync_info_update,
1227 .metadata_update_start = metadata_update_start,
1228 .metadata_update_finish = metadata_update_finish,
1229 .metadata_update_cancel = metadata_update_cancel,
1230 .area_resyncing = area_resyncing,
1231 .add_new_disk = add_new_disk,
1232 .add_new_disk_cancel = add_new_disk_cancel,
1233 .new_disk_ack = new_disk_ack,
1234 .remove_disk = remove_disk,
1235 .load_bitmaps = load_bitmaps,
1236 .gather_bitmaps = gather_bitmaps,
1237 .lock_all_bitmaps = lock_all_bitmaps,
1238 .unlock_all_bitmaps = unlock_all_bitmaps,
1239 };
1240
1241 static int __init cluster_init(void)
1242 {
1243 pr_warn("md-cluster: EXPERIMENTAL. Use with caution\n");
1244 pr_info("Registering Cluster MD functions\n");
1245 register_md_cluster_operations(&cluster_ops, THIS_MODULE);
1246 return 0;
1247 }
1248
1249 static void cluster_exit(void)
1250 {
1251 unregister_md_cluster_operations();
1252 }
1253
1254 module_init(cluster_init);
1255 module_exit(cluster_exit);
1256 MODULE_AUTHOR("SUSE");
1257 MODULE_LICENSE("GPL");
1258 MODULE_DESCRIPTION("Clustering support for MD");
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