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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
23struct 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
34struct suspend_info {
35 int slot;
36 sector_t lo;
37 sector_t hi;
38 struct list_head list;
39};
40
41struct 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
65
66struct md_cluster_info {
67 /* dlm lock space and resources for clustered raid. */
68 dlm_lockspace_t *lockspace;
69 int slot_number;
70 struct completion completion;
71 struct mutex recv_mutex;
72 struct dlm_lock_resource *bitmap_lockres;
73 struct dlm_lock_resource **other_bitmap_lockres;
74 struct dlm_lock_resource *resync_lockres;
75 struct list_head suspend_list;
76 spinlock_t suspend_lock;
77 struct md_thread *recovery_thread;
78 unsigned long recovery_map;
79 /* communication loc resources */
80 struct dlm_lock_resource *ack_lockres;
81 struct dlm_lock_resource *message_lockres;
82 struct dlm_lock_resource *token_lockres;
83 struct dlm_lock_resource *no_new_dev_lockres;
84 struct md_thread *recv_thread;
85 struct completion newdisk_completion;
86 wait_queue_head_t wait;
87 unsigned long state;
88};
89
90enum msg_type {
91 METADATA_UPDATED = 0,
92 RESYNCING,
93 NEWDISK,
94 REMOVE,
95 RE_ADD,
96 BITMAP_NEEDS_SYNC,
97};
98
99struct cluster_msg {
100 __le32 type;
101 __le32 slot;
102 /* TODO: Unionize this for smaller footprint */
103 __le64 low;
104 __le64 high;
105 char uuid[16];
106 __le32 raid_slot;
107};
108
109static void sync_ast(void *arg)
110{
111 struct dlm_lock_resource *res;
112
113 res = arg;
114 complete(&res->completion);
115}
116
117static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
118{
119 int ret = 0;
120
121 ret = dlm_lock(res->ls, mode, &res->lksb,
122 res->flags, res->name, strlen(res->name),
123 0, sync_ast, res, res->bast);
124 if (ret)
125 return ret;
126 wait_for_completion(&res->completion);
127 if (res->lksb.sb_status == 0)
128 res->mode = mode;
129 return res->lksb.sb_status;
130}
131
132static int dlm_unlock_sync(struct dlm_lock_resource *res)
133{
134 return dlm_lock_sync(res, DLM_LOCK_NL);
135}
136
137static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
138 char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
139{
140 struct dlm_lock_resource *res = NULL;
141 int ret, namelen;
142 struct md_cluster_info *cinfo = mddev->cluster_info;
143
144 res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
145 if (!res)
146 return NULL;
147 init_completion(&res->completion);
148 res->ls = cinfo->lockspace;
149 res->mddev = mddev;
150 res->mode = DLM_LOCK_IV;
151 namelen = strlen(name);
152 res->name = kzalloc(namelen + 1, GFP_KERNEL);
153 if (!res->name) {
154 pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
155 goto out_err;
156 }
157 strlcpy(res->name, name, namelen + 1);
158 if (with_lvb) {
159 res->lksb.sb_lvbptr = kzalloc(LVB_SIZE, GFP_KERNEL);
160 if (!res->lksb.sb_lvbptr) {
161 pr_err("md-cluster: Unable to allocate LVB for resource %s\n", name);
162 goto out_err;
163 }
164 res->flags = DLM_LKF_VALBLK;
165 }
166
167 if (bastfn)
168 res->bast = bastfn;
169
170 res->flags |= DLM_LKF_EXPEDITE;
171
172 ret = dlm_lock_sync(res, DLM_LOCK_NL);
173 if (ret) {
174 pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
175 goto out_err;
176 }
177 res->flags &= ~DLM_LKF_EXPEDITE;
178 res->flags |= DLM_LKF_CONVERT;
179
180 return res;
181out_err:
182 kfree(res->lksb.sb_lvbptr);
183 kfree(res->name);
184 kfree(res);
185 return NULL;
186}
187
188static void lockres_free(struct dlm_lock_resource *res)
189{
190 int ret;
191
192 if (!res)
193 return;
194
195 /* cancel a lock request or a conversion request that is blocked */
196 res->flags |= DLM_LKF_CANCEL;
197retry:
198 ret = dlm_unlock(res->ls, res->lksb.sb_lkid, 0, &res->lksb, res);
199 if (unlikely(ret != 0)) {
200 pr_info("%s: failed to unlock %s return %d\n", __func__, res->name, ret);
201
202 /* if a lock conversion is cancelled, then the lock is put
203 * back to grant queue, need to ensure it is unlocked */
204 if (ret == -DLM_ECANCEL)
205 goto retry;
206 }
207 res->flags &= ~DLM_LKF_CANCEL;
208 wait_for_completion(&res->completion);
209
210 kfree(res->name);
211 kfree(res->lksb.sb_lvbptr);
212 kfree(res);
213}
214
215static void add_resync_info(struct dlm_lock_resource *lockres,
216 sector_t lo, sector_t hi)
217{
218 struct resync_info *ri;
219
220 ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
221 ri->lo = cpu_to_le64(lo);
222 ri->hi = cpu_to_le64(hi);
223}
224
225static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
226{
227 struct resync_info ri;
228 struct suspend_info *s = NULL;
229 sector_t hi = 0;
230
231 dlm_lock_sync(lockres, DLM_LOCK_CR);
232 memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
233 hi = le64_to_cpu(ri.hi);
234 if (hi > 0) {
235 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
236 if (!s)
237 goto out;
238 s->hi = hi;
239 s->lo = le64_to_cpu(ri.lo);
240 }
241 dlm_unlock_sync(lockres);
242out:
243 return s;
244}
245
246static void recover_bitmaps(struct md_thread *thread)
247{
248 struct mddev *mddev = thread->mddev;
249 struct md_cluster_info *cinfo = mddev->cluster_info;
250 struct dlm_lock_resource *bm_lockres;
251 char str[64];
252 int slot, ret;
253 struct suspend_info *s, *tmp;
254 sector_t lo, hi;
255
256 while (cinfo->recovery_map) {
257 slot = fls64((u64)cinfo->recovery_map) - 1;
258
259 /* Clear suspend_area associated with the bitmap */
260 spin_lock_irq(&cinfo->suspend_lock);
261 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
262 if (slot == s->slot) {
263 list_del(&s->list);
264 kfree(s);
265 }
266 spin_unlock_irq(&cinfo->suspend_lock);
267
268 snprintf(str, 64, "bitmap%04d", slot);
269 bm_lockres = lockres_init(mddev, str, NULL, 1);
270 if (!bm_lockres) {
271 pr_err("md-cluster: Cannot initialize bitmaps\n");
272 goto clear_bit;
273 }
274
275 ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
276 if (ret) {
277 pr_err("md-cluster: Could not DLM lock %s: %d\n",
278 str, ret);
279 goto clear_bit;
280 }
281 ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
282 if (ret) {
283 pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
284 goto dlm_unlock;
285 }
286 if (hi > 0) {
287 /* TODO:Wait for current resync to get over */
288 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
289 if (lo < mddev->recovery_cp)
290 mddev->recovery_cp = lo;
291 md_check_recovery(mddev);
292 }
293dlm_unlock:
294 dlm_unlock_sync(bm_lockres);
295clear_bit:
296 lockres_free(bm_lockres);
297 clear_bit(slot, &cinfo->recovery_map);
298 }
299}
300
301static void recover_prep(void *arg)
302{
303 struct mddev *mddev = arg;
304 struct md_cluster_info *cinfo = mddev->cluster_info;
305 set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
306}
307
308static void __recover_slot(struct mddev *mddev, int slot)
309{
310 struct md_cluster_info *cinfo = mddev->cluster_info;
311
312 set_bit(slot, &cinfo->recovery_map);
313 if (!cinfo->recovery_thread) {
314 cinfo->recovery_thread = md_register_thread(recover_bitmaps,
315 mddev, "recover");
316 if (!cinfo->recovery_thread) {
317 pr_warn("md-cluster: Could not create recovery thread\n");
318 return;
319 }
320 }
321 md_wakeup_thread(cinfo->recovery_thread);
322}
323
324static void recover_slot(void *arg, struct dlm_slot *slot)
325{
326 struct mddev *mddev = arg;
327 struct md_cluster_info *cinfo = mddev->cluster_info;
328
329 pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
330 mddev->bitmap_info.cluster_name,
331 slot->nodeid, slot->slot,
332 cinfo->slot_number);
333 /* deduct one since dlm slot starts from one while the num of
334 * cluster-md begins with 0 */
335 __recover_slot(mddev, slot->slot - 1);
336}
337
338static void recover_done(void *arg, struct dlm_slot *slots,
339 int num_slots, int our_slot,
340 uint32_t generation)
341{
342 struct mddev *mddev = arg;
343 struct md_cluster_info *cinfo = mddev->cluster_info;
344
345 cinfo->slot_number = our_slot;
346 /* completion is only need to be complete when node join cluster,
347 * it doesn't need to run during another node's failure */
348 if (test_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state)) {
349 complete(&cinfo->completion);
350 clear_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
351 }
352 clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
353}
354
355/* the ops is called when node join the cluster, and do lock recovery
356 * if node failure occurs */
357static const struct dlm_lockspace_ops md_ls_ops = {
358 .recover_prep = recover_prep,
359 .recover_slot = recover_slot,
360 .recover_done = recover_done,
361};
362
363/*
364 * The BAST function for the ack lock resource
365 * This function wakes up the receive thread in
366 * order to receive and process the message.
367 */
368static void ack_bast(void *arg, int mode)
369{
370 struct dlm_lock_resource *res = arg;
371 struct md_cluster_info *cinfo = res->mddev->cluster_info;
372
373 if (mode == DLM_LOCK_EX)
374 md_wakeup_thread(cinfo->recv_thread);
375}
376
377static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
378{
379 struct suspend_info *s, *tmp;
380
381 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
382 if (slot == s->slot) {
383 list_del(&s->list);
384 kfree(s);
385 break;
386 }
387}
388
389static void remove_suspend_info(struct mddev *mddev, int slot)
390{
391 struct md_cluster_info *cinfo = mddev->cluster_info;
392 spin_lock_irq(&cinfo->suspend_lock);
393 __remove_suspend_info(cinfo, slot);
394 spin_unlock_irq(&cinfo->suspend_lock);
395 mddev->pers->quiesce(mddev, 2);
396}
397
398
399static void process_suspend_info(struct mddev *mddev,
400 int slot, sector_t lo, sector_t hi)
401{
402 struct md_cluster_info *cinfo = mddev->cluster_info;
403 struct suspend_info *s;
404
405 if (!hi) {
406 remove_suspend_info(mddev, slot);
407 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
408 md_wakeup_thread(mddev->thread);
409 return;
410 }
411 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
412 if (!s)
413 return;
414 s->slot = slot;
415 s->lo = lo;
416 s->hi = hi;
417 mddev->pers->quiesce(mddev, 1);
418 mddev->pers->quiesce(mddev, 0);
419 spin_lock_irq(&cinfo->suspend_lock);
420 /* Remove existing entry (if exists) before adding */
421 __remove_suspend_info(cinfo, slot);
422 list_add(&s->list, &cinfo->suspend_list);
423 spin_unlock_irq(&cinfo->suspend_lock);
424 mddev->pers->quiesce(mddev, 2);
425}
426
427static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
428{
429 char disk_uuid[64];
430 struct md_cluster_info *cinfo = mddev->cluster_info;
431 char event_name[] = "EVENT=ADD_DEVICE";
432 char raid_slot[16];
433 char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
434 int len;
435
436 len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
437 sprintf(disk_uuid + len, "%pU", cmsg->uuid);
438 snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
439 pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
440 init_completion(&cinfo->newdisk_completion);
441 set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
442 kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
443 wait_for_completion_timeout(&cinfo->newdisk_completion,
444 NEW_DEV_TIMEOUT);
445 clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
446}
447
448
449static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
450{
451 struct md_cluster_info *cinfo = mddev->cluster_info;
452 mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
453 set_bit(MD_RELOAD_SB, &mddev->flags);
454 dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
455 md_wakeup_thread(mddev->thread);
456}
457
458static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
459{
460 struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev,
461 le32_to_cpu(msg->raid_slot));
462
463 if (rdev) {
464 set_bit(ClusterRemove, &rdev->flags);
465 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
466 md_wakeup_thread(mddev->thread);
467 }
468 else
469 pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
470 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
471}
472
473static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
474{
475 struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev,
476 le32_to_cpu(msg->raid_slot));
477
478 if (rdev && test_bit(Faulty, &rdev->flags))
479 clear_bit(Faulty, &rdev->flags);
480 else
481 pr_warn("%s: %d Could not find disk(%d) which is faulty",
482 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
483}
484
485static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
486{
487 if (WARN(mddev->cluster_info->slot_number - 1 == le32_to_cpu(msg->slot),
488 "node %d received it's own msg\n", le32_to_cpu(msg->slot)))
489 return;
490 switch (le32_to_cpu(msg->type)) {
491 case METADATA_UPDATED:
492 process_metadata_update(mddev, msg);
493 break;
494 case RESYNCING:
495 process_suspend_info(mddev, le32_to_cpu(msg->slot),
496 le64_to_cpu(msg->low),
497 le64_to_cpu(msg->high));
498 break;
499 case NEWDISK:
500 process_add_new_disk(mddev, msg);
501 break;
502 case REMOVE:
503 process_remove_disk(mddev, msg);
504 break;
505 case RE_ADD:
506 process_readd_disk(mddev, msg);
507 break;
508 case BITMAP_NEEDS_SYNC:
509 __recover_slot(mddev, le32_to_cpu(msg->slot));
510 break;
511 default:
512 pr_warn("%s:%d Received unknown message from %d\n",
513 __func__, __LINE__, msg->slot);
514 }
515}
516
517/*
518 * thread for receiving message
519 */
520static void recv_daemon(struct md_thread *thread)
521{
522 struct md_cluster_info *cinfo = thread->mddev->cluster_info;
523 struct dlm_lock_resource *ack_lockres = cinfo->ack_lockres;
524 struct dlm_lock_resource *message_lockres = cinfo->message_lockres;
525 struct cluster_msg msg;
526 int ret;
527
528 mutex_lock(&cinfo->recv_mutex);
529 /*get CR on Message*/
530 if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) {
531 pr_err("md/raid1:failed to get CR on MESSAGE\n");
532 mutex_unlock(&cinfo->recv_mutex);
533 return;
534 }
535
536 /* read lvb and wake up thread to process this message_lockres */
537 memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg));
538 process_recvd_msg(thread->mddev, &msg);
539
540 /*release CR on ack_lockres*/
541 ret = dlm_unlock_sync(ack_lockres);
542 if (unlikely(ret != 0))
543 pr_info("unlock ack failed return %d\n", ret);
544 /*up-convert to PR on message_lockres*/
545 ret = dlm_lock_sync(message_lockres, DLM_LOCK_PR);
546 if (unlikely(ret != 0))
547 pr_info("lock PR on msg failed return %d\n", ret);
548 /*get CR on ack_lockres again*/
549 ret = dlm_lock_sync(ack_lockres, DLM_LOCK_CR);
550 if (unlikely(ret != 0))
551 pr_info("lock CR on ack failed return %d\n", ret);
552 /*release CR on message_lockres*/
553 ret = dlm_unlock_sync(message_lockres);
554 if (unlikely(ret != 0))
555 pr_info("unlock msg failed return %d\n", ret);
556 mutex_unlock(&cinfo->recv_mutex);
557}
558
559/* lock_token()
560 * Takes the lock on the TOKEN lock resource so no other
561 * node can communicate while the operation is underway.
562 */
563static int lock_token(struct md_cluster_info *cinfo)
564{
565 int error;
566
567 error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
568 if (error)
569 pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
570 __func__, __LINE__, error);
571
572 /* Lock the receive sequence */
573 mutex_lock(&cinfo->recv_mutex);
574 return error;
575}
576
577/* lock_comm()
578 * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
579 */
580static int lock_comm(struct md_cluster_info *cinfo)
581{
582 wait_event(cinfo->wait,
583 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
584
585 return lock_token(cinfo);
586}
587
588static void unlock_comm(struct md_cluster_info *cinfo)
589{
590 WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
591 mutex_unlock(&cinfo->recv_mutex);
592 dlm_unlock_sync(cinfo->token_lockres);
593 clear_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state);
594 wake_up(&cinfo->wait);
595}
596
597/* __sendmsg()
598 * This function performs the actual sending of the message. This function is
599 * usually called after performing the encompassing operation
600 * The function:
601 * 1. Grabs the message lockresource in EX mode
602 * 2. Copies the message to the message LVB
603 * 3. Downconverts message lockresource to CW
604 * 4. Upconverts ack lock resource from CR to EX. This forces the BAST on other nodes
605 * and the other nodes read the message. The thread will wait here until all other
606 * nodes have released ack lock resource.
607 * 5. Downconvert ack lockresource to CR
608 */
609static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
610{
611 int error;
612 int slot = cinfo->slot_number - 1;
613
614 cmsg->slot = cpu_to_le32(slot);
615 /*get EX on Message*/
616 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
617 if (error) {
618 pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
619 goto failed_message;
620 }
621
622 memcpy(cinfo->message_lockres->lksb.sb_lvbptr, (void *)cmsg,
623 sizeof(struct cluster_msg));
624 /*down-convert EX to CW on Message*/
625 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CW);
626 if (error) {
627 pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
628 error);
629 goto failed_ack;
630 }
631
632 /*up-convert CR to EX on Ack*/
633 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
634 if (error) {
635 pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
636 error);
637 goto failed_ack;
638 }
639
640 /*down-convert EX to CR on Ack*/
641 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
642 if (error) {
643 pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
644 error);
645 goto failed_ack;
646 }
647
648failed_ack:
649 error = dlm_unlock_sync(cinfo->message_lockres);
650 if (unlikely(error != 0)) {
651 pr_err("md-cluster: failed convert to NL on MESSAGE(%d)\n",
652 error);
653 /* in case the message can't be released due to some reason */
654 goto failed_ack;
655 }
656failed_message:
657 return error;
658}
659
660static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
661{
662 int ret;
663
664 lock_comm(cinfo);
665 ret = __sendmsg(cinfo, cmsg);
666 unlock_comm(cinfo);
667 return ret;
668}
669
670static int gather_all_resync_info(struct mddev *mddev, int total_slots)
671{
672 struct md_cluster_info *cinfo = mddev->cluster_info;
673 int i, ret = 0;
674 struct dlm_lock_resource *bm_lockres;
675 struct suspend_info *s;
676 char str[64];
677 sector_t lo, hi;
678
679
680 for (i = 0; i < total_slots; i++) {
681 memset(str, '\0', 64);
682 snprintf(str, 64, "bitmap%04d", i);
683 bm_lockres = lockres_init(mddev, str, NULL, 1);
684 if (!bm_lockres)
685 return -ENOMEM;
686 if (i == (cinfo->slot_number - 1)) {
687 lockres_free(bm_lockres);
688 continue;
689 }
690
691 bm_lockres->flags |= DLM_LKF_NOQUEUE;
692 ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
693 if (ret == -EAGAIN) {
694 memset(bm_lockres->lksb.sb_lvbptr, '\0', LVB_SIZE);
695 s = read_resync_info(mddev, bm_lockres);
696 if (s) {
697 pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
698 __func__, __LINE__,
699 (unsigned long long) s->lo,
700 (unsigned long long) s->hi, i);
701 spin_lock_irq(&cinfo->suspend_lock);
702 s->slot = i;
703 list_add(&s->list, &cinfo->suspend_list);
704 spin_unlock_irq(&cinfo->suspend_lock);
705 }
706 ret = 0;
707 lockres_free(bm_lockres);
708 continue;
709 }
710 if (ret) {
711 lockres_free(bm_lockres);
712 goto out;
713 }
714
715 /* Read the disk bitmap sb and check if it needs recovery */
716 ret = bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
717 if (ret) {
718 pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
719 lockres_free(bm_lockres);
720 continue;
721 }
722 if ((hi > 0) && (lo < mddev->recovery_cp)) {
723 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
724 mddev->recovery_cp = lo;
725 md_check_recovery(mddev);
726 }
727
728 dlm_unlock_sync(bm_lockres);
729 lockres_free(bm_lockres);
730 }
731out:
732 return ret;
733}
734
735static int join(struct mddev *mddev, int nodes)
736{
737 struct md_cluster_info *cinfo;
738 int ret, ops_rv;
739 char str[64];
740
741 cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
742 if (!cinfo)
743 return -ENOMEM;
744
745 INIT_LIST_HEAD(&cinfo->suspend_list);
746 spin_lock_init(&cinfo->suspend_lock);
747 init_completion(&cinfo->completion);
748 set_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
749 init_waitqueue_head(&cinfo->wait);
750 mutex_init(&cinfo->recv_mutex);
751
752 mddev->cluster_info = cinfo;
753
754 memset(str, 0, 64);
755 sprintf(str, "%pU", mddev->uuid);
756 ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
757 DLM_LSFL_FS, LVB_SIZE,
758 &md_ls_ops, mddev, &ops_rv, &cinfo->lockspace);
759 if (ret)
760 goto err;
761 wait_for_completion(&cinfo->completion);
762 if (nodes < cinfo->slot_number) {
763 pr_err("md-cluster: Slot allotted(%d) is greater than available slots(%d).",
764 cinfo->slot_number, nodes);
765 ret = -ERANGE;
766 goto err;
767 }
768 /* Initiate the communication resources */
769 ret = -ENOMEM;
770 cinfo->recv_thread = md_register_thread(recv_daemon, mddev, "cluster_recv");
771 if (!cinfo->recv_thread) {
772 pr_err("md-cluster: cannot allocate memory for recv_thread!\n");
773 goto err;
774 }
775 cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
776 if (!cinfo->message_lockres)
777 goto err;
778 cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
779 if (!cinfo->token_lockres)
780 goto err;
781 cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
782 if (!cinfo->ack_lockres)
783 goto err;
784 cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
785 if (!cinfo->no_new_dev_lockres)
786 goto err;
787
788 /* get sync CR lock on ACK. */
789 if (dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR))
790 pr_err("md-cluster: failed to get a sync CR lock on ACK!(%d)\n",
791 ret);
792 /* get sync CR lock on no-new-dev. */
793 if (dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR))
794 pr_err("md-cluster: failed to get a sync CR lock on no-new-dev!(%d)\n", ret);
795
796
797 pr_info("md-cluster: Joined cluster %s slot %d\n", str, cinfo->slot_number);
798 snprintf(str, 64, "bitmap%04d", cinfo->slot_number - 1);
799 cinfo->bitmap_lockres = lockres_init(mddev, str, NULL, 1);
800 if (!cinfo->bitmap_lockres)
801 goto err;
802 if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
803 pr_err("Failed to get bitmap lock\n");
804 ret = -EINVAL;
805 goto err;
806 }
807
808 cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
809 if (!cinfo->resync_lockres)
810 goto err;
811
812 ret = gather_all_resync_info(mddev, nodes);
813 if (ret)
814 goto err;
815
816 return 0;
817err:
818 lockres_free(cinfo->message_lockres);
819 lockres_free(cinfo->token_lockres);
820 lockres_free(cinfo->ack_lockres);
821 lockres_free(cinfo->no_new_dev_lockres);
822 lockres_free(cinfo->resync_lockres);
823 lockres_free(cinfo->bitmap_lockres);
824 if (cinfo->lockspace)
825 dlm_release_lockspace(cinfo->lockspace, 2);
826 mddev->cluster_info = NULL;
827 kfree(cinfo);
828 return ret;
829}
830
831static void resync_bitmap(struct mddev *mddev)
832{
833 struct md_cluster_info *cinfo = mddev->cluster_info;
834 struct cluster_msg cmsg = {0};
835 int err;
836
837 cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
838 err = sendmsg(cinfo, &cmsg);
839 if (err)
840 pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
841 __func__, __LINE__, err);
842}
843
844static void unlock_all_bitmaps(struct mddev *mddev);
845static int leave(struct mddev *mddev)
846{
847 struct md_cluster_info *cinfo = mddev->cluster_info;
848
849 if (!cinfo)
850 return 0;
851
852 /* BITMAP_NEEDS_SYNC message should be sent when node
853 * is leaving the cluster with dirty bitmap, also we
854 * can only deliver it when dlm connection is available */
855 if (cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector)
856 resync_bitmap(mddev);
857
858 md_unregister_thread(&cinfo->recovery_thread);
859 md_unregister_thread(&cinfo->recv_thread);
860 lockres_free(cinfo->message_lockres);
861 lockres_free(cinfo->token_lockres);
862 lockres_free(cinfo->ack_lockres);
863 lockres_free(cinfo->no_new_dev_lockres);
864 lockres_free(cinfo->resync_lockres);
865 lockres_free(cinfo->bitmap_lockres);
866 unlock_all_bitmaps(mddev);
867 dlm_release_lockspace(cinfo->lockspace, 2);
868 return 0;
869}
870
871/* slot_number(): Returns the MD slot number to use
872 * DLM starts the slot numbers from 1, wheras cluster-md
873 * wants the number to be from zero, so we deduct one
874 */
875static int slot_number(struct mddev *mddev)
876{
877 struct md_cluster_info *cinfo = mddev->cluster_info;
878
879 return cinfo->slot_number - 1;
880}
881
882/*
883 * Check if the communication is already locked, else lock the communication
884 * channel.
885 * If it is already locked, token is in EX mode, and hence lock_token()
886 * should not be called.
887 */
888static int metadata_update_start(struct mddev *mddev)
889{
890 struct md_cluster_info *cinfo = mddev->cluster_info;
891
892 wait_event(cinfo->wait,
893 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state) ||
894 test_and_clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state));
895
896 /* If token is already locked, return 0 */
897 if (cinfo->token_lockres->mode == DLM_LOCK_EX)
898 return 0;
899
900 return lock_token(cinfo);
901}
902
903static int metadata_update_finish(struct mddev *mddev)
904{
905 struct md_cluster_info *cinfo = mddev->cluster_info;
906 struct cluster_msg cmsg;
907 struct md_rdev *rdev;
908 int ret = 0;
909 int raid_slot = -1;
910
911 memset(&cmsg, 0, sizeof(cmsg));
912 cmsg.type = cpu_to_le32(METADATA_UPDATED);
913 /* Pick up a good active device number to send.
914 */
915 rdev_for_each(rdev, mddev)
916 if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
917 raid_slot = rdev->desc_nr;
918 break;
919 }
920 if (raid_slot >= 0) {
921 cmsg.raid_slot = cpu_to_le32(raid_slot);
922 ret = __sendmsg(cinfo, &cmsg);
923 } else
924 pr_warn("md-cluster: No good device id found to send\n");
925 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
926 unlock_comm(cinfo);
927 return ret;
928}
929
930static void metadata_update_cancel(struct mddev *mddev)
931{
932 struct md_cluster_info *cinfo = mddev->cluster_info;
933 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
934 unlock_comm(cinfo);
935}
936
937static int resync_start(struct mddev *mddev)
938{
939 struct md_cluster_info *cinfo = mddev->cluster_info;
940 cinfo->resync_lockres->flags |= DLM_LKF_NOQUEUE;
941 return dlm_lock_sync(cinfo->resync_lockres, DLM_LOCK_EX);
942}
943
944static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
945{
946 struct md_cluster_info *cinfo = mddev->cluster_info;
947 struct resync_info ri;
948 struct cluster_msg cmsg = {0};
949
950 /* do not send zero again, if we have sent before */
951 if (hi == 0) {
952 memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
953 if (le64_to_cpu(ri.hi) == 0)
954 return 0;
955 }
956
957 add_resync_info(cinfo->bitmap_lockres, lo, hi);
958 /* Re-acquire the lock to refresh LVB */
959 dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
960 cmsg.type = cpu_to_le32(RESYNCING);
961 cmsg.low = cpu_to_le64(lo);
962 cmsg.high = cpu_to_le64(hi);
963
964 return sendmsg(cinfo, &cmsg);
965}
966
967static int resync_finish(struct mddev *mddev)
968{
969 struct md_cluster_info *cinfo = mddev->cluster_info;
970 cinfo->resync_lockres->flags &= ~DLM_LKF_NOQUEUE;
971 dlm_unlock_sync(cinfo->resync_lockres);
972 return resync_info_update(mddev, 0, 0);
973}
974
975static int area_resyncing(struct mddev *mddev, int direction,
976 sector_t lo, sector_t hi)
977{
978 struct md_cluster_info *cinfo = mddev->cluster_info;
979 int ret = 0;
980 struct suspend_info *s;
981
982 if ((direction == READ) &&
983 test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
984 return 1;
985
986 spin_lock_irq(&cinfo->suspend_lock);
987 if (list_empty(&cinfo->suspend_list))
988 goto out;
989 list_for_each_entry(s, &cinfo->suspend_list, list)
990 if (hi > s->lo && lo < s->hi) {
991 ret = 1;
992 break;
993 }
994out:
995 spin_unlock_irq(&cinfo->suspend_lock);
996 return ret;
997}
998
999/* add_new_disk() - initiates a disk add
1000 * However, if this fails before writing md_update_sb(),
1001 * add_new_disk_cancel() must be called to release token lock
1002 */
1003static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
1004{
1005 struct md_cluster_info *cinfo = mddev->cluster_info;
1006 struct cluster_msg cmsg;
1007 int ret = 0;
1008 struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1009 char *uuid = sb->device_uuid;
1010
1011 memset(&cmsg, 0, sizeof(cmsg));
1012 cmsg.type = cpu_to_le32(NEWDISK);
1013 memcpy(cmsg.uuid, uuid, 16);
1014 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1015 lock_comm(cinfo);
1016 ret = __sendmsg(cinfo, &cmsg);
1017 if (ret)
1018 return ret;
1019 cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
1020 ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
1021 cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;
1022 /* Some node does not "see" the device */
1023 if (ret == -EAGAIN)
1024 ret = -ENOENT;
1025 if (ret)
1026 unlock_comm(cinfo);
1027 else {
1028 dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
1029 /* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
1030 * will run soon after add_new_disk, the below path will be
1031 * invoked:
1032 * md_wakeup_thread(mddev->thread)
1033 * -> conf->thread (raid1d)
1034 * -> md_check_recovery -> md_update_sb
1035 * -> metadata_update_start/finish
1036 * MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
1037 *
1038 * For other failure cases, metadata_update_cancel and
1039 * add_new_disk_cancel also clear below bit as well.
1040 * */
1041 set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1042 wake_up(&cinfo->wait);
1043 }
1044 return ret;
1045}
1046
1047static void add_new_disk_cancel(struct mddev *mddev)
1048{
1049 struct md_cluster_info *cinfo = mddev->cluster_info;
1050 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1051 unlock_comm(cinfo);
1052}
1053
1054static int new_disk_ack(struct mddev *mddev, bool ack)
1055{
1056 struct md_cluster_info *cinfo = mddev->cluster_info;
1057
1058 if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
1059 pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
1060 return -EINVAL;
1061 }
1062
1063 if (ack)
1064 dlm_unlock_sync(cinfo->no_new_dev_lockres);
1065 complete(&cinfo->newdisk_completion);
1066 return 0;
1067}
1068
1069static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1070{
1071 struct cluster_msg cmsg = {0};
1072 struct md_cluster_info *cinfo = mddev->cluster_info;
1073 cmsg.type = cpu_to_le32(REMOVE);
1074 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1075 return sendmsg(cinfo, &cmsg);
1076}
1077
1078static int lock_all_bitmaps(struct mddev *mddev)
1079{
1080 int slot, my_slot, ret, held = 1, i = 0;
1081 char str[64];
1082 struct md_cluster_info *cinfo = mddev->cluster_info;
1083
1084 cinfo->other_bitmap_lockres = kzalloc((mddev->bitmap_info.nodes - 1) *
1085 sizeof(struct dlm_lock_resource *),
1086 GFP_KERNEL);
1087 if (!cinfo->other_bitmap_lockres) {
1088 pr_err("md: can't alloc mem for other bitmap locks\n");
1089 return 0;
1090 }
1091
1092 my_slot = slot_number(mddev);
1093 for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
1094 if (slot == my_slot)
1095 continue;
1096
1097 memset(str, '\0', 64);
1098 snprintf(str, 64, "bitmap%04d", slot);
1099 cinfo->other_bitmap_lockres[i] = lockres_init(mddev, str, NULL, 1);
1100 if (!cinfo->other_bitmap_lockres[i])
1101 return -ENOMEM;
1102
1103 cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
1104 ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
1105 if (ret)
1106 held = -1;
1107 i++;
1108 }
1109
1110 return held;
1111}
1112
1113static void unlock_all_bitmaps(struct mddev *mddev)
1114{
1115 struct md_cluster_info *cinfo = mddev->cluster_info;
1116 int i;
1117
1118 /* release other node's bitmap lock if they are existed */
1119 if (cinfo->other_bitmap_lockres) {
1120 for (i = 0; i < mddev->bitmap_info.nodes - 1; i++) {
1121 if (cinfo->other_bitmap_lockres[i]) {
1122 dlm_unlock_sync(cinfo->other_bitmap_lockres[i]);
1123 lockres_free(cinfo->other_bitmap_lockres[i]);
1124 }
1125 }
1126 kfree(cinfo->other_bitmap_lockres);
1127 }
1128}
1129
1130static int gather_bitmaps(struct md_rdev *rdev)
1131{
1132 int sn, err;
1133 sector_t lo, hi;
1134 struct cluster_msg cmsg = {0};
1135 struct mddev *mddev = rdev->mddev;
1136 struct md_cluster_info *cinfo = mddev->cluster_info;
1137
1138 cmsg.type = cpu_to_le32(RE_ADD);
1139 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1140 err = sendmsg(cinfo, &cmsg);
1141 if (err)
1142 goto out;
1143
1144 for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
1145 if (sn == (cinfo->slot_number - 1))
1146 continue;
1147 err = bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
1148 if (err) {
1149 pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
1150 goto out;
1151 }
1152 if ((hi > 0) && (lo < mddev->recovery_cp))
1153 mddev->recovery_cp = lo;
1154 }
1155out:
1156 return err;
1157}
1158
1159static struct md_cluster_operations cluster_ops = {
1160 .join = join,
1161 .leave = leave,
1162 .slot_number = slot_number,
1163 .resync_start = resync_start,
1164 .resync_finish = resync_finish,
1165 .resync_info_update = resync_info_update,
1166 .metadata_update_start = metadata_update_start,
1167 .metadata_update_finish = metadata_update_finish,
1168 .metadata_update_cancel = metadata_update_cancel,
1169 .area_resyncing = area_resyncing,
1170 .add_new_disk = add_new_disk,
1171 .add_new_disk_cancel = add_new_disk_cancel,
1172 .new_disk_ack = new_disk_ack,
1173 .remove_disk = remove_disk,
1174 .gather_bitmaps = gather_bitmaps,
1175 .lock_all_bitmaps = lock_all_bitmaps,
1176 .unlock_all_bitmaps = unlock_all_bitmaps,
1177};
1178
1179static int __init cluster_init(void)
1180{
1181 pr_warn("md-cluster: EXPERIMENTAL. Use with caution\n");
1182 pr_info("Registering Cluster MD functions\n");
1183 register_md_cluster_operations(&cluster_ops, THIS_MODULE);
1184 return 0;
1185}
1186
1187static void cluster_exit(void)
1188{
1189 unregister_md_cluster_operations();
1190}
1191
1192module_init(cluster_init);
1193module_exit(cluster_exit);
1194MODULE_AUTHOR("SUSE");
1195MODULE_LICENSE("GPL");
1196MODULE_DESCRIPTION("Clustering support for MD");
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/kthread.h>
14#include <linux/dlm.h>
15#include <linux/sched.h>
16#include <linux/raid/md_p.h>
17#include "md.h"
18#include "bitmap.h"
19#include "md-cluster.h"
20
21#define LVB_SIZE 64
22#define NEW_DEV_TIMEOUT 5000
23
24struct dlm_lock_resource {
25 dlm_lockspace_t *ls;
26 struct dlm_lksb lksb;
27 char *name; /* lock name. */
28 uint32_t flags; /* flags to pass to dlm_lock() */
29 wait_queue_head_t sync_locking; /* wait queue for synchronized locking */
30 bool sync_locking_done;
31 void (*bast)(void *arg, int mode); /* blocking AST function pointer*/
32 struct mddev *mddev; /* pointing back to mddev. */
33 int mode;
34};
35
36struct suspend_info {
37 int slot;
38 sector_t lo;
39 sector_t hi;
40 struct list_head list;
41};
42
43struct resync_info {
44 __le64 lo;
45 __le64 hi;
46};
47
48/* md_cluster_info flags */
49#define MD_CLUSTER_WAITING_FOR_NEWDISK 1
50#define MD_CLUSTER_SUSPEND_READ_BALANCING 2
51#define MD_CLUSTER_BEGIN_JOIN_CLUSTER 3
52
53/* Lock the send communication. This is done through
54 * bit manipulation as opposed to a mutex in order to
55 * accomodate lock and hold. See next comment.
56 */
57#define MD_CLUSTER_SEND_LOCK 4
58/* If cluster operations (such as adding a disk) must lock the
59 * communication channel, so as to perform extra operations
60 * (update metadata) and no other operation is allowed on the
61 * MD. Token needs to be locked and held until the operation
62 * completes witha md_update_sb(), which would eventually release
63 * the lock.
64 */
65#define MD_CLUSTER_SEND_LOCKED_ALREADY 5
66/* We should receive message after node joined cluster and
67 * set up all the related infos such as bitmap and personality */
68#define MD_CLUSTER_ALREADY_IN_CLUSTER 6
69#define MD_CLUSTER_PENDING_RECV_EVENT 7
70
71
72struct md_cluster_info {
73 /* dlm lock space and resources for clustered raid. */
74 dlm_lockspace_t *lockspace;
75 int slot_number;
76 struct completion completion;
77 struct mutex recv_mutex;
78 struct dlm_lock_resource *bitmap_lockres;
79 struct dlm_lock_resource **other_bitmap_lockres;
80 struct dlm_lock_resource *resync_lockres;
81 struct list_head suspend_list;
82 spinlock_t suspend_lock;
83 struct md_thread *recovery_thread;
84 unsigned long recovery_map;
85 /* communication loc resources */
86 struct dlm_lock_resource *ack_lockres;
87 struct dlm_lock_resource *message_lockres;
88 struct dlm_lock_resource *token_lockres;
89 struct dlm_lock_resource *no_new_dev_lockres;
90 struct md_thread *recv_thread;
91 struct completion newdisk_completion;
92 wait_queue_head_t wait;
93 unsigned long state;
94 /* record the region in RESYNCING message */
95 sector_t sync_low;
96 sector_t sync_hi;
97};
98
99enum msg_type {
100 METADATA_UPDATED = 0,
101 RESYNCING,
102 NEWDISK,
103 REMOVE,
104 RE_ADD,
105 BITMAP_NEEDS_SYNC,
106};
107
108struct cluster_msg {
109 __le32 type;
110 __le32 slot;
111 /* TODO: Unionize this for smaller footprint */
112 __le64 low;
113 __le64 high;
114 char uuid[16];
115 __le32 raid_slot;
116};
117
118static void sync_ast(void *arg)
119{
120 struct dlm_lock_resource *res;
121
122 res = arg;
123 res->sync_locking_done = true;
124 wake_up(&res->sync_locking);
125}
126
127static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
128{
129 int ret = 0;
130
131 ret = dlm_lock(res->ls, mode, &res->lksb,
132 res->flags, res->name, strlen(res->name),
133 0, sync_ast, res, res->bast);
134 if (ret)
135 return ret;
136 wait_event(res->sync_locking, res->sync_locking_done);
137 res->sync_locking_done = false;
138 if (res->lksb.sb_status == 0)
139 res->mode = mode;
140 return res->lksb.sb_status;
141}
142
143static int dlm_unlock_sync(struct dlm_lock_resource *res)
144{
145 return dlm_lock_sync(res, DLM_LOCK_NL);
146}
147
148/*
149 * An variation of dlm_lock_sync, which make lock request could
150 * be interrupted
151 */
152static int dlm_lock_sync_interruptible(struct dlm_lock_resource *res, int mode,
153 struct mddev *mddev)
154{
155 int ret = 0;
156
157 ret = dlm_lock(res->ls, mode, &res->lksb,
158 res->flags, res->name, strlen(res->name),
159 0, sync_ast, res, res->bast);
160 if (ret)
161 return ret;
162
163 wait_event(res->sync_locking, res->sync_locking_done
164 || kthread_should_stop()
165 || test_bit(MD_CLOSING, &mddev->flags));
166 if (!res->sync_locking_done) {
167 /*
168 * the convert queue contains the lock request when request is
169 * interrupted, and sync_ast could still be run, so need to
170 * cancel the request and reset completion
171 */
172 ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_CANCEL,
173 &res->lksb, res);
174 res->sync_locking_done = false;
175 if (unlikely(ret != 0))
176 pr_info("failed to cancel previous lock request "
177 "%s return %d\n", res->name, ret);
178 return -EPERM;
179 } else
180 res->sync_locking_done = false;
181 if (res->lksb.sb_status == 0)
182 res->mode = mode;
183 return res->lksb.sb_status;
184}
185
186static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
187 char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
188{
189 struct dlm_lock_resource *res = NULL;
190 int ret, namelen;
191 struct md_cluster_info *cinfo = mddev->cluster_info;
192
193 res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
194 if (!res)
195 return NULL;
196 init_waitqueue_head(&res->sync_locking);
197 res->sync_locking_done = false;
198 res->ls = cinfo->lockspace;
199 res->mddev = mddev;
200 res->mode = DLM_LOCK_IV;
201 namelen = strlen(name);
202 res->name = kzalloc(namelen + 1, GFP_KERNEL);
203 if (!res->name) {
204 pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
205 goto out_err;
206 }
207 strlcpy(res->name, name, namelen + 1);
208 if (with_lvb) {
209 res->lksb.sb_lvbptr = kzalloc(LVB_SIZE, GFP_KERNEL);
210 if (!res->lksb.sb_lvbptr) {
211 pr_err("md-cluster: Unable to allocate LVB for resource %s\n", name);
212 goto out_err;
213 }
214 res->flags = DLM_LKF_VALBLK;
215 }
216
217 if (bastfn)
218 res->bast = bastfn;
219
220 res->flags |= DLM_LKF_EXPEDITE;
221
222 ret = dlm_lock_sync(res, DLM_LOCK_NL);
223 if (ret) {
224 pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
225 goto out_err;
226 }
227 res->flags &= ~DLM_LKF_EXPEDITE;
228 res->flags |= DLM_LKF_CONVERT;
229
230 return res;
231out_err:
232 kfree(res->lksb.sb_lvbptr);
233 kfree(res->name);
234 kfree(res);
235 return NULL;
236}
237
238static void lockres_free(struct dlm_lock_resource *res)
239{
240 int ret = 0;
241
242 if (!res)
243 return;
244
245 /*
246 * use FORCEUNLOCK flag, so we can unlock even the lock is on the
247 * waiting or convert queue
248 */
249 ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_FORCEUNLOCK,
250 &res->lksb, res);
251 if (unlikely(ret != 0))
252 pr_err("failed to unlock %s return %d\n", res->name, ret);
253 else
254 wait_event(res->sync_locking, res->sync_locking_done);
255
256 kfree(res->name);
257 kfree(res->lksb.sb_lvbptr);
258 kfree(res);
259}
260
261static void add_resync_info(struct dlm_lock_resource *lockres,
262 sector_t lo, sector_t hi)
263{
264 struct resync_info *ri;
265
266 ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
267 ri->lo = cpu_to_le64(lo);
268 ri->hi = cpu_to_le64(hi);
269}
270
271static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
272{
273 struct resync_info ri;
274 struct suspend_info *s = NULL;
275 sector_t hi = 0;
276
277 dlm_lock_sync(lockres, DLM_LOCK_CR);
278 memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
279 hi = le64_to_cpu(ri.hi);
280 if (hi > 0) {
281 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
282 if (!s)
283 goto out;
284 s->hi = hi;
285 s->lo = le64_to_cpu(ri.lo);
286 }
287 dlm_unlock_sync(lockres);
288out:
289 return s;
290}
291
292static void recover_bitmaps(struct md_thread *thread)
293{
294 struct mddev *mddev = thread->mddev;
295 struct md_cluster_info *cinfo = mddev->cluster_info;
296 struct dlm_lock_resource *bm_lockres;
297 char str[64];
298 int slot, ret;
299 struct suspend_info *s, *tmp;
300 sector_t lo, hi;
301
302 while (cinfo->recovery_map) {
303 slot = fls64((u64)cinfo->recovery_map) - 1;
304
305 /* Clear suspend_area associated with the bitmap */
306 spin_lock_irq(&cinfo->suspend_lock);
307 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
308 if (slot == s->slot) {
309 list_del(&s->list);
310 kfree(s);
311 }
312 spin_unlock_irq(&cinfo->suspend_lock);
313
314 snprintf(str, 64, "bitmap%04d", slot);
315 bm_lockres = lockres_init(mddev, str, NULL, 1);
316 if (!bm_lockres) {
317 pr_err("md-cluster: Cannot initialize bitmaps\n");
318 goto clear_bit;
319 }
320
321 ret = dlm_lock_sync_interruptible(bm_lockres, DLM_LOCK_PW, mddev);
322 if (ret) {
323 pr_err("md-cluster: Could not DLM lock %s: %d\n",
324 str, ret);
325 goto clear_bit;
326 }
327 ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
328 if (ret) {
329 pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
330 goto clear_bit;
331 }
332 if (hi > 0) {
333 if (lo < mddev->recovery_cp)
334 mddev->recovery_cp = lo;
335 /* wake up thread to continue resync in case resync
336 * is not finished */
337 if (mddev->recovery_cp != MaxSector) {
338 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
339 md_wakeup_thread(mddev->thread);
340 }
341 }
342clear_bit:
343 lockres_free(bm_lockres);
344 clear_bit(slot, &cinfo->recovery_map);
345 }
346}
347
348static void recover_prep(void *arg)
349{
350 struct mddev *mddev = arg;
351 struct md_cluster_info *cinfo = mddev->cluster_info;
352 set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
353}
354
355static void __recover_slot(struct mddev *mddev, int slot)
356{
357 struct md_cluster_info *cinfo = mddev->cluster_info;
358
359 set_bit(slot, &cinfo->recovery_map);
360 if (!cinfo->recovery_thread) {
361 cinfo->recovery_thread = md_register_thread(recover_bitmaps,
362 mddev, "recover");
363 if (!cinfo->recovery_thread) {
364 pr_warn("md-cluster: Could not create recovery thread\n");
365 return;
366 }
367 }
368 md_wakeup_thread(cinfo->recovery_thread);
369}
370
371static void recover_slot(void *arg, struct dlm_slot *slot)
372{
373 struct mddev *mddev = arg;
374 struct md_cluster_info *cinfo = mddev->cluster_info;
375
376 pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
377 mddev->bitmap_info.cluster_name,
378 slot->nodeid, slot->slot,
379 cinfo->slot_number);
380 /* deduct one since dlm slot starts from one while the num of
381 * cluster-md begins with 0 */
382 __recover_slot(mddev, slot->slot - 1);
383}
384
385static void recover_done(void *arg, struct dlm_slot *slots,
386 int num_slots, int our_slot,
387 uint32_t generation)
388{
389 struct mddev *mddev = arg;
390 struct md_cluster_info *cinfo = mddev->cluster_info;
391
392 cinfo->slot_number = our_slot;
393 /* completion is only need to be complete when node join cluster,
394 * it doesn't need to run during another node's failure */
395 if (test_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state)) {
396 complete(&cinfo->completion);
397 clear_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
398 }
399 clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
400}
401
402/* the ops is called when node join the cluster, and do lock recovery
403 * if node failure occurs */
404static const struct dlm_lockspace_ops md_ls_ops = {
405 .recover_prep = recover_prep,
406 .recover_slot = recover_slot,
407 .recover_done = recover_done,
408};
409
410/*
411 * The BAST function for the ack lock resource
412 * This function wakes up the receive thread in
413 * order to receive and process the message.
414 */
415static void ack_bast(void *arg, int mode)
416{
417 struct dlm_lock_resource *res = arg;
418 struct md_cluster_info *cinfo = res->mddev->cluster_info;
419
420 if (mode == DLM_LOCK_EX) {
421 if (test_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state))
422 md_wakeup_thread(cinfo->recv_thread);
423 else
424 set_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state);
425 }
426}
427
428static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
429{
430 struct suspend_info *s, *tmp;
431
432 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
433 if (slot == s->slot) {
434 list_del(&s->list);
435 kfree(s);
436 break;
437 }
438}
439
440static void remove_suspend_info(struct mddev *mddev, int slot)
441{
442 struct md_cluster_info *cinfo = mddev->cluster_info;
443 spin_lock_irq(&cinfo->suspend_lock);
444 __remove_suspend_info(cinfo, slot);
445 spin_unlock_irq(&cinfo->suspend_lock);
446 mddev->pers->quiesce(mddev, 2);
447}
448
449
450static void process_suspend_info(struct mddev *mddev,
451 int slot, sector_t lo, sector_t hi)
452{
453 struct md_cluster_info *cinfo = mddev->cluster_info;
454 struct suspend_info *s;
455
456 if (!hi) {
457 remove_suspend_info(mddev, slot);
458 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
459 md_wakeup_thread(mddev->thread);
460 return;
461 }
462
463 /*
464 * The bitmaps are not same for different nodes
465 * if RESYNCING is happening in one node, then
466 * the node which received the RESYNCING message
467 * probably will perform resync with the region
468 * [lo, hi] again, so we could reduce resync time
469 * a lot if we can ensure that the bitmaps among
470 * different nodes are match up well.
471 *
472 * sync_low/hi is used to record the region which
473 * arrived in the previous RESYNCING message,
474 *
475 * Call bitmap_sync_with_cluster to clear
476 * NEEDED_MASK and set RESYNC_MASK since
477 * resync thread is running in another node,
478 * so we don't need to do the resync again
479 * with the same section */
480 bitmap_sync_with_cluster(mddev, cinfo->sync_low,
481 cinfo->sync_hi,
482 lo, hi);
483 cinfo->sync_low = lo;
484 cinfo->sync_hi = hi;
485
486 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
487 if (!s)
488 return;
489 s->slot = slot;
490 s->lo = lo;
491 s->hi = hi;
492 mddev->pers->quiesce(mddev, 1);
493 mddev->pers->quiesce(mddev, 0);
494 spin_lock_irq(&cinfo->suspend_lock);
495 /* Remove existing entry (if exists) before adding */
496 __remove_suspend_info(cinfo, slot);
497 list_add(&s->list, &cinfo->suspend_list);
498 spin_unlock_irq(&cinfo->suspend_lock);
499 mddev->pers->quiesce(mddev, 2);
500}
501
502static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
503{
504 char disk_uuid[64];
505 struct md_cluster_info *cinfo = mddev->cluster_info;
506 char event_name[] = "EVENT=ADD_DEVICE";
507 char raid_slot[16];
508 char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
509 int len;
510
511 len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
512 sprintf(disk_uuid + len, "%pU", cmsg->uuid);
513 snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
514 pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
515 init_completion(&cinfo->newdisk_completion);
516 set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
517 kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
518 wait_for_completion_timeout(&cinfo->newdisk_completion,
519 NEW_DEV_TIMEOUT);
520 clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
521}
522
523
524static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
525{
526 struct md_cluster_info *cinfo = mddev->cluster_info;
527 mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
528 set_bit(MD_RELOAD_SB, &mddev->flags);
529 dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
530 md_wakeup_thread(mddev->thread);
531}
532
533static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
534{
535 struct md_rdev *rdev;
536
537 rcu_read_lock();
538 rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
539 if (rdev) {
540 set_bit(ClusterRemove, &rdev->flags);
541 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
542 md_wakeup_thread(mddev->thread);
543 }
544 else
545 pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
546 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
547 rcu_read_unlock();
548}
549
550static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
551{
552 struct md_rdev *rdev;
553
554 rcu_read_lock();
555 rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
556 if (rdev && test_bit(Faulty, &rdev->flags))
557 clear_bit(Faulty, &rdev->flags);
558 else
559 pr_warn("%s: %d Could not find disk(%d) which is faulty",
560 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
561 rcu_read_unlock();
562}
563
564static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
565{
566 int ret = 0;
567
568 if (WARN(mddev->cluster_info->slot_number - 1 == le32_to_cpu(msg->slot),
569 "node %d received it's own msg\n", le32_to_cpu(msg->slot)))
570 return -1;
571 switch (le32_to_cpu(msg->type)) {
572 case METADATA_UPDATED:
573 process_metadata_update(mddev, msg);
574 break;
575 case RESYNCING:
576 process_suspend_info(mddev, le32_to_cpu(msg->slot),
577 le64_to_cpu(msg->low),
578 le64_to_cpu(msg->high));
579 break;
580 case NEWDISK:
581 process_add_new_disk(mddev, msg);
582 break;
583 case REMOVE:
584 process_remove_disk(mddev, msg);
585 break;
586 case RE_ADD:
587 process_readd_disk(mddev, msg);
588 break;
589 case BITMAP_NEEDS_SYNC:
590 __recover_slot(mddev, le32_to_cpu(msg->slot));
591 break;
592 default:
593 ret = -1;
594 pr_warn("%s:%d Received unknown message from %d\n",
595 __func__, __LINE__, msg->slot);
596 }
597 return ret;
598}
599
600/*
601 * thread for receiving message
602 */
603static void recv_daemon(struct md_thread *thread)
604{
605 struct md_cluster_info *cinfo = thread->mddev->cluster_info;
606 struct dlm_lock_resource *ack_lockres = cinfo->ack_lockres;
607 struct dlm_lock_resource *message_lockres = cinfo->message_lockres;
608 struct cluster_msg msg;
609 int ret;
610
611 mutex_lock(&cinfo->recv_mutex);
612 /*get CR on Message*/
613 if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) {
614 pr_err("md/raid1:failed to get CR on MESSAGE\n");
615 mutex_unlock(&cinfo->recv_mutex);
616 return;
617 }
618
619 /* read lvb and wake up thread to process this message_lockres */
620 memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg));
621 ret = process_recvd_msg(thread->mddev, &msg);
622 if (ret)
623 goto out;
624
625 /*release CR on ack_lockres*/
626 ret = dlm_unlock_sync(ack_lockres);
627 if (unlikely(ret != 0))
628 pr_info("unlock ack failed return %d\n", ret);
629 /*up-convert to PR on message_lockres*/
630 ret = dlm_lock_sync(message_lockres, DLM_LOCK_PR);
631 if (unlikely(ret != 0))
632 pr_info("lock PR on msg failed return %d\n", ret);
633 /*get CR on ack_lockres again*/
634 ret = dlm_lock_sync(ack_lockres, DLM_LOCK_CR);
635 if (unlikely(ret != 0))
636 pr_info("lock CR on ack failed return %d\n", ret);
637out:
638 /*release CR on message_lockres*/
639 ret = dlm_unlock_sync(message_lockres);
640 if (unlikely(ret != 0))
641 pr_info("unlock msg failed return %d\n", ret);
642 mutex_unlock(&cinfo->recv_mutex);
643}
644
645/* lock_token()
646 * Takes the lock on the TOKEN lock resource so no other
647 * node can communicate while the operation is underway.
648 */
649static int lock_token(struct md_cluster_info *cinfo)
650{
651 int error;
652
653 error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
654 if (error)
655 pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
656 __func__, __LINE__, error);
657
658 /* Lock the receive sequence */
659 mutex_lock(&cinfo->recv_mutex);
660 return error;
661}
662
663/* lock_comm()
664 * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
665 */
666static int lock_comm(struct md_cluster_info *cinfo)
667{
668 wait_event(cinfo->wait,
669 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
670
671 return lock_token(cinfo);
672}
673
674static void unlock_comm(struct md_cluster_info *cinfo)
675{
676 WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
677 mutex_unlock(&cinfo->recv_mutex);
678 dlm_unlock_sync(cinfo->token_lockres);
679 clear_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state);
680 wake_up(&cinfo->wait);
681}
682
683/* __sendmsg()
684 * This function performs the actual sending of the message. This function is
685 * usually called after performing the encompassing operation
686 * The function:
687 * 1. Grabs the message lockresource in EX mode
688 * 2. Copies the message to the message LVB
689 * 3. Downconverts message lockresource to CW
690 * 4. Upconverts ack lock resource from CR to EX. This forces the BAST on other nodes
691 * and the other nodes read the message. The thread will wait here until all other
692 * nodes have released ack lock resource.
693 * 5. Downconvert ack lockresource to CR
694 */
695static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
696{
697 int error;
698 int slot = cinfo->slot_number - 1;
699
700 cmsg->slot = cpu_to_le32(slot);
701 /*get EX on Message*/
702 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
703 if (error) {
704 pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
705 goto failed_message;
706 }
707
708 memcpy(cinfo->message_lockres->lksb.sb_lvbptr, (void *)cmsg,
709 sizeof(struct cluster_msg));
710 /*down-convert EX to CW on Message*/
711 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CW);
712 if (error) {
713 pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
714 error);
715 goto failed_ack;
716 }
717
718 /*up-convert CR to EX on Ack*/
719 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
720 if (error) {
721 pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
722 error);
723 goto failed_ack;
724 }
725
726 /*down-convert EX to CR on Ack*/
727 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
728 if (error) {
729 pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
730 error);
731 goto failed_ack;
732 }
733
734failed_ack:
735 error = dlm_unlock_sync(cinfo->message_lockres);
736 if (unlikely(error != 0)) {
737 pr_err("md-cluster: failed convert to NL on MESSAGE(%d)\n",
738 error);
739 /* in case the message can't be released due to some reason */
740 goto failed_ack;
741 }
742failed_message:
743 return error;
744}
745
746static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
747{
748 int ret;
749
750 lock_comm(cinfo);
751 ret = __sendmsg(cinfo, cmsg);
752 unlock_comm(cinfo);
753 return ret;
754}
755
756static int gather_all_resync_info(struct mddev *mddev, int total_slots)
757{
758 struct md_cluster_info *cinfo = mddev->cluster_info;
759 int i, ret = 0;
760 struct dlm_lock_resource *bm_lockres;
761 struct suspend_info *s;
762 char str[64];
763 sector_t lo, hi;
764
765
766 for (i = 0; i < total_slots; i++) {
767 memset(str, '\0', 64);
768 snprintf(str, 64, "bitmap%04d", i);
769 bm_lockres = lockres_init(mddev, str, NULL, 1);
770 if (!bm_lockres)
771 return -ENOMEM;
772 if (i == (cinfo->slot_number - 1)) {
773 lockres_free(bm_lockres);
774 continue;
775 }
776
777 bm_lockres->flags |= DLM_LKF_NOQUEUE;
778 ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
779 if (ret == -EAGAIN) {
780 memset(bm_lockres->lksb.sb_lvbptr, '\0', LVB_SIZE);
781 s = read_resync_info(mddev, bm_lockres);
782 if (s) {
783 pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
784 __func__, __LINE__,
785 (unsigned long long) s->lo,
786 (unsigned long long) s->hi, i);
787 spin_lock_irq(&cinfo->suspend_lock);
788 s->slot = i;
789 list_add(&s->list, &cinfo->suspend_list);
790 spin_unlock_irq(&cinfo->suspend_lock);
791 }
792 ret = 0;
793 lockres_free(bm_lockres);
794 continue;
795 }
796 if (ret) {
797 lockres_free(bm_lockres);
798 goto out;
799 }
800
801 /* Read the disk bitmap sb and check if it needs recovery */
802 ret = bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
803 if (ret) {
804 pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
805 lockres_free(bm_lockres);
806 continue;
807 }
808 if ((hi > 0) && (lo < mddev->recovery_cp)) {
809 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
810 mddev->recovery_cp = lo;
811 md_check_recovery(mddev);
812 }
813
814 lockres_free(bm_lockres);
815 }
816out:
817 return ret;
818}
819
820static int join(struct mddev *mddev, int nodes)
821{
822 struct md_cluster_info *cinfo;
823 int ret, ops_rv;
824 char str[64];
825
826 cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
827 if (!cinfo)
828 return -ENOMEM;
829
830 INIT_LIST_HEAD(&cinfo->suspend_list);
831 spin_lock_init(&cinfo->suspend_lock);
832 init_completion(&cinfo->completion);
833 set_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
834 init_waitqueue_head(&cinfo->wait);
835 mutex_init(&cinfo->recv_mutex);
836
837 mddev->cluster_info = cinfo;
838
839 memset(str, 0, 64);
840 sprintf(str, "%pU", mddev->uuid);
841 ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
842 DLM_LSFL_FS, LVB_SIZE,
843 &md_ls_ops, mddev, &ops_rv, &cinfo->lockspace);
844 if (ret)
845 goto err;
846 wait_for_completion(&cinfo->completion);
847 if (nodes < cinfo->slot_number) {
848 pr_err("md-cluster: Slot allotted(%d) is greater than available slots(%d).",
849 cinfo->slot_number, nodes);
850 ret = -ERANGE;
851 goto err;
852 }
853 /* Initiate the communication resources */
854 ret = -ENOMEM;
855 cinfo->recv_thread = md_register_thread(recv_daemon, mddev, "cluster_recv");
856 if (!cinfo->recv_thread) {
857 pr_err("md-cluster: cannot allocate memory for recv_thread!\n");
858 goto err;
859 }
860 cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
861 if (!cinfo->message_lockres)
862 goto err;
863 cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
864 if (!cinfo->token_lockres)
865 goto err;
866 cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
867 if (!cinfo->no_new_dev_lockres)
868 goto err;
869
870 ret = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
871 if (ret) {
872 ret = -EAGAIN;
873 pr_err("md-cluster: can't join cluster to avoid lock issue\n");
874 goto err;
875 }
876 cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
877 if (!cinfo->ack_lockres) {
878 ret = -ENOMEM;
879 goto err;
880 }
881 /* get sync CR lock on ACK. */
882 if (dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR))
883 pr_err("md-cluster: failed to get a sync CR lock on ACK!(%d)\n",
884 ret);
885 dlm_unlock_sync(cinfo->token_lockres);
886 /* get sync CR lock on no-new-dev. */
887 if (dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR))
888 pr_err("md-cluster: failed to get a sync CR lock on no-new-dev!(%d)\n", ret);
889
890
891 pr_info("md-cluster: Joined cluster %s slot %d\n", str, cinfo->slot_number);
892 snprintf(str, 64, "bitmap%04d", cinfo->slot_number - 1);
893 cinfo->bitmap_lockres = lockres_init(mddev, str, NULL, 1);
894 if (!cinfo->bitmap_lockres) {
895 ret = -ENOMEM;
896 goto err;
897 }
898 if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
899 pr_err("Failed to get bitmap lock\n");
900 ret = -EINVAL;
901 goto err;
902 }
903
904 cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
905 if (!cinfo->resync_lockres) {
906 ret = -ENOMEM;
907 goto err;
908 }
909
910 return 0;
911err:
912 md_unregister_thread(&cinfo->recovery_thread);
913 md_unregister_thread(&cinfo->recv_thread);
914 lockres_free(cinfo->message_lockres);
915 lockres_free(cinfo->token_lockres);
916 lockres_free(cinfo->ack_lockres);
917 lockres_free(cinfo->no_new_dev_lockres);
918 lockres_free(cinfo->resync_lockres);
919 lockres_free(cinfo->bitmap_lockres);
920 if (cinfo->lockspace)
921 dlm_release_lockspace(cinfo->lockspace, 2);
922 mddev->cluster_info = NULL;
923 kfree(cinfo);
924 return ret;
925}
926
927static void load_bitmaps(struct mddev *mddev, int total_slots)
928{
929 struct md_cluster_info *cinfo = mddev->cluster_info;
930
931 /* load all the node's bitmap info for resync */
932 if (gather_all_resync_info(mddev, total_slots))
933 pr_err("md-cluster: failed to gather all resyn infos\n");
934 set_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state);
935 /* wake up recv thread in case something need to be handled */
936 if (test_and_clear_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state))
937 md_wakeup_thread(cinfo->recv_thread);
938}
939
940static void resync_bitmap(struct mddev *mddev)
941{
942 struct md_cluster_info *cinfo = mddev->cluster_info;
943 struct cluster_msg cmsg = {0};
944 int err;
945
946 cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
947 err = sendmsg(cinfo, &cmsg);
948 if (err)
949 pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
950 __func__, __LINE__, err);
951}
952
953static void unlock_all_bitmaps(struct mddev *mddev);
954static int leave(struct mddev *mddev)
955{
956 struct md_cluster_info *cinfo = mddev->cluster_info;
957
958 if (!cinfo)
959 return 0;
960
961 /* BITMAP_NEEDS_SYNC message should be sent when node
962 * is leaving the cluster with dirty bitmap, also we
963 * can only deliver it when dlm connection is available */
964 if (cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector)
965 resync_bitmap(mddev);
966
967 md_unregister_thread(&cinfo->recovery_thread);
968 md_unregister_thread(&cinfo->recv_thread);
969 lockres_free(cinfo->message_lockres);
970 lockres_free(cinfo->token_lockres);
971 lockres_free(cinfo->ack_lockres);
972 lockres_free(cinfo->no_new_dev_lockres);
973 lockres_free(cinfo->resync_lockres);
974 lockres_free(cinfo->bitmap_lockres);
975 unlock_all_bitmaps(mddev);
976 dlm_release_lockspace(cinfo->lockspace, 2);
977 return 0;
978}
979
980/* slot_number(): Returns the MD slot number to use
981 * DLM starts the slot numbers from 1, wheras cluster-md
982 * wants the number to be from zero, so we deduct one
983 */
984static int slot_number(struct mddev *mddev)
985{
986 struct md_cluster_info *cinfo = mddev->cluster_info;
987
988 return cinfo->slot_number - 1;
989}
990
991/*
992 * Check if the communication is already locked, else lock the communication
993 * channel.
994 * If it is already locked, token is in EX mode, and hence lock_token()
995 * should not be called.
996 */
997static int metadata_update_start(struct mddev *mddev)
998{
999 struct md_cluster_info *cinfo = mddev->cluster_info;
1000
1001 wait_event(cinfo->wait,
1002 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state) ||
1003 test_and_clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state));
1004
1005 /* If token is already locked, return 0 */
1006 if (cinfo->token_lockres->mode == DLM_LOCK_EX)
1007 return 0;
1008
1009 return lock_token(cinfo);
1010}
1011
1012static int metadata_update_finish(struct mddev *mddev)
1013{
1014 struct md_cluster_info *cinfo = mddev->cluster_info;
1015 struct cluster_msg cmsg;
1016 struct md_rdev *rdev;
1017 int ret = 0;
1018 int raid_slot = -1;
1019
1020 memset(&cmsg, 0, sizeof(cmsg));
1021 cmsg.type = cpu_to_le32(METADATA_UPDATED);
1022 /* Pick up a good active device number to send.
1023 */
1024 rdev_for_each(rdev, mddev)
1025 if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
1026 raid_slot = rdev->desc_nr;
1027 break;
1028 }
1029 if (raid_slot >= 0) {
1030 cmsg.raid_slot = cpu_to_le32(raid_slot);
1031 ret = __sendmsg(cinfo, &cmsg);
1032 } else
1033 pr_warn("md-cluster: No good device id found to send\n");
1034 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1035 unlock_comm(cinfo);
1036 return ret;
1037}
1038
1039static void metadata_update_cancel(struct mddev *mddev)
1040{
1041 struct md_cluster_info *cinfo = mddev->cluster_info;
1042 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1043 unlock_comm(cinfo);
1044}
1045
1046static int resync_start(struct mddev *mddev)
1047{
1048 struct md_cluster_info *cinfo = mddev->cluster_info;
1049 return dlm_lock_sync_interruptible(cinfo->resync_lockres, DLM_LOCK_EX, mddev);
1050}
1051
1052static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
1053{
1054 struct md_cluster_info *cinfo = mddev->cluster_info;
1055 struct resync_info ri;
1056 struct cluster_msg cmsg = {0};
1057
1058 /* do not send zero again, if we have sent before */
1059 if (hi == 0) {
1060 memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
1061 if (le64_to_cpu(ri.hi) == 0)
1062 return 0;
1063 }
1064
1065 add_resync_info(cinfo->bitmap_lockres, lo, hi);
1066 /* Re-acquire the lock to refresh LVB */
1067 dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
1068 cmsg.type = cpu_to_le32(RESYNCING);
1069 cmsg.low = cpu_to_le64(lo);
1070 cmsg.high = cpu_to_le64(hi);
1071
1072 return sendmsg(cinfo, &cmsg);
1073}
1074
1075static int resync_finish(struct mddev *mddev)
1076{
1077 struct md_cluster_info *cinfo = mddev->cluster_info;
1078 dlm_unlock_sync(cinfo->resync_lockres);
1079 return resync_info_update(mddev, 0, 0);
1080}
1081
1082static int area_resyncing(struct mddev *mddev, int direction,
1083 sector_t lo, sector_t hi)
1084{
1085 struct md_cluster_info *cinfo = mddev->cluster_info;
1086 int ret = 0;
1087 struct suspend_info *s;
1088
1089 if ((direction == READ) &&
1090 test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
1091 return 1;
1092
1093 spin_lock_irq(&cinfo->suspend_lock);
1094 if (list_empty(&cinfo->suspend_list))
1095 goto out;
1096 list_for_each_entry(s, &cinfo->suspend_list, list)
1097 if (hi > s->lo && lo < s->hi) {
1098 ret = 1;
1099 break;
1100 }
1101out:
1102 spin_unlock_irq(&cinfo->suspend_lock);
1103 return ret;
1104}
1105
1106/* add_new_disk() - initiates a disk add
1107 * However, if this fails before writing md_update_sb(),
1108 * add_new_disk_cancel() must be called to release token lock
1109 */
1110static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
1111{
1112 struct md_cluster_info *cinfo = mddev->cluster_info;
1113 struct cluster_msg cmsg;
1114 int ret = 0;
1115 struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1116 char *uuid = sb->device_uuid;
1117
1118 memset(&cmsg, 0, sizeof(cmsg));
1119 cmsg.type = cpu_to_le32(NEWDISK);
1120 memcpy(cmsg.uuid, uuid, 16);
1121 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1122 lock_comm(cinfo);
1123 ret = __sendmsg(cinfo, &cmsg);
1124 if (ret)
1125 return ret;
1126 cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
1127 ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
1128 cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;
1129 /* Some node does not "see" the device */
1130 if (ret == -EAGAIN)
1131 ret = -ENOENT;
1132 if (ret)
1133 unlock_comm(cinfo);
1134 else {
1135 dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
1136 /* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
1137 * will run soon after add_new_disk, the below path will be
1138 * invoked:
1139 * md_wakeup_thread(mddev->thread)
1140 * -> conf->thread (raid1d)
1141 * -> md_check_recovery -> md_update_sb
1142 * -> metadata_update_start/finish
1143 * MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
1144 *
1145 * For other failure cases, metadata_update_cancel and
1146 * add_new_disk_cancel also clear below bit as well.
1147 * */
1148 set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1149 wake_up(&cinfo->wait);
1150 }
1151 return ret;
1152}
1153
1154static void add_new_disk_cancel(struct mddev *mddev)
1155{
1156 struct md_cluster_info *cinfo = mddev->cluster_info;
1157 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1158 unlock_comm(cinfo);
1159}
1160
1161static int new_disk_ack(struct mddev *mddev, bool ack)
1162{
1163 struct md_cluster_info *cinfo = mddev->cluster_info;
1164
1165 if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
1166 pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
1167 return -EINVAL;
1168 }
1169
1170 if (ack)
1171 dlm_unlock_sync(cinfo->no_new_dev_lockres);
1172 complete(&cinfo->newdisk_completion);
1173 return 0;
1174}
1175
1176static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1177{
1178 struct cluster_msg cmsg = {0};
1179 struct md_cluster_info *cinfo = mddev->cluster_info;
1180 cmsg.type = cpu_to_le32(REMOVE);
1181 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1182 return sendmsg(cinfo, &cmsg);
1183}
1184
1185static int lock_all_bitmaps(struct mddev *mddev)
1186{
1187 int slot, my_slot, ret, held = 1, i = 0;
1188 char str[64];
1189 struct md_cluster_info *cinfo = mddev->cluster_info;
1190
1191 cinfo->other_bitmap_lockres = kzalloc((mddev->bitmap_info.nodes - 1) *
1192 sizeof(struct dlm_lock_resource *),
1193 GFP_KERNEL);
1194 if (!cinfo->other_bitmap_lockres) {
1195 pr_err("md: can't alloc mem for other bitmap locks\n");
1196 return 0;
1197 }
1198
1199 my_slot = slot_number(mddev);
1200 for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
1201 if (slot == my_slot)
1202 continue;
1203
1204 memset(str, '\0', 64);
1205 snprintf(str, 64, "bitmap%04d", slot);
1206 cinfo->other_bitmap_lockres[i] = lockres_init(mddev, str, NULL, 1);
1207 if (!cinfo->other_bitmap_lockres[i])
1208 return -ENOMEM;
1209
1210 cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
1211 ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
1212 if (ret)
1213 held = -1;
1214 i++;
1215 }
1216
1217 return held;
1218}
1219
1220static void unlock_all_bitmaps(struct mddev *mddev)
1221{
1222 struct md_cluster_info *cinfo = mddev->cluster_info;
1223 int i;
1224
1225 /* release other node's bitmap lock if they are existed */
1226 if (cinfo->other_bitmap_lockres) {
1227 for (i = 0; i < mddev->bitmap_info.nodes - 1; i++) {
1228 if (cinfo->other_bitmap_lockres[i]) {
1229 lockres_free(cinfo->other_bitmap_lockres[i]);
1230 }
1231 }
1232 kfree(cinfo->other_bitmap_lockres);
1233 }
1234}
1235
1236static int gather_bitmaps(struct md_rdev *rdev)
1237{
1238 int sn, err;
1239 sector_t lo, hi;
1240 struct cluster_msg cmsg = {0};
1241 struct mddev *mddev = rdev->mddev;
1242 struct md_cluster_info *cinfo = mddev->cluster_info;
1243
1244 cmsg.type = cpu_to_le32(RE_ADD);
1245 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1246 err = sendmsg(cinfo, &cmsg);
1247 if (err)
1248 goto out;
1249
1250 for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
1251 if (sn == (cinfo->slot_number - 1))
1252 continue;
1253 err = bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
1254 if (err) {
1255 pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
1256 goto out;
1257 }
1258 if ((hi > 0) && (lo < mddev->recovery_cp))
1259 mddev->recovery_cp = lo;
1260 }
1261out:
1262 return err;
1263}
1264
1265static struct md_cluster_operations cluster_ops = {
1266 .join = join,
1267 .leave = leave,
1268 .slot_number = slot_number,
1269 .resync_start = resync_start,
1270 .resync_finish = resync_finish,
1271 .resync_info_update = resync_info_update,
1272 .metadata_update_start = metadata_update_start,
1273 .metadata_update_finish = metadata_update_finish,
1274 .metadata_update_cancel = metadata_update_cancel,
1275 .area_resyncing = area_resyncing,
1276 .add_new_disk = add_new_disk,
1277 .add_new_disk_cancel = add_new_disk_cancel,
1278 .new_disk_ack = new_disk_ack,
1279 .remove_disk = remove_disk,
1280 .load_bitmaps = load_bitmaps,
1281 .gather_bitmaps = gather_bitmaps,
1282 .lock_all_bitmaps = lock_all_bitmaps,
1283 .unlock_all_bitmaps = unlock_all_bitmaps,
1284};
1285
1286static int __init cluster_init(void)
1287{
1288 pr_warn("md-cluster: EXPERIMENTAL. Use with caution\n");
1289 pr_info("Registering Cluster MD functions\n");
1290 register_md_cluster_operations(&cluster_ops, THIS_MODULE);
1291 return 0;
1292}
1293
1294static void cluster_exit(void)
1295{
1296 unregister_md_cluster_operations();
1297}
1298
1299module_init(cluster_init);
1300module_exit(cluster_exit);
1301MODULE_AUTHOR("SUSE");
1302MODULE_LICENSE("GPL");
1303MODULE_DESCRIPTION("Clustering support for MD");