2 * Copyright (C) 2015, SUSE
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)
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>
19 #include "md-cluster.h"
22 #define NEW_DEV_TIMEOUT 5000
24 struct dlm_lock_resource {
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. */
40 struct list_head list;
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
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.
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
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
72 struct md_cluster_info {
73 /* dlm lock space and resources for clustered raid. */
74 dlm_lockspace_t *lockspace;
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;
94 /* record the region in RESYNCING message */
100 METADATA_UPDATED = 0,
111 /* TODO: Unionize this for smaller footprint */
118 static void sync_ast(void *arg)
120 struct dlm_lock_resource *res;
123 res->sync_locking_done = true;
124 wake_up(&res->sync_locking);
127 static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
131 ret = dlm_lock(res->ls, mode, &res->lksb,
132 res->flags, res->name, strlen(res->name),
133 0, sync_ast, res, res->bast);
136 wait_event(res->sync_locking, res->sync_locking_done);
137 res->sync_locking_done = false;
138 if (res->lksb.sb_status == 0)
140 return res->lksb.sb_status;
143 static int dlm_unlock_sync(struct dlm_lock_resource *res)
145 return dlm_lock_sync(res, DLM_LOCK_NL);
149 * An variation of dlm_lock_sync, which make lock request could
152 static int dlm_lock_sync_interruptible(struct dlm_lock_resource *res, int mode,
157 ret = dlm_lock(res->ls, mode, &res->lksb,
158 res->flags, res->name, strlen(res->name),
159 0, sync_ast, res, res->bast);
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) {
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
172 ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_CANCEL,
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);
180 res->sync_locking_done = false;
181 if (res->lksb.sb_status == 0)
183 return res->lksb.sb_status;
186 static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
187 char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
189 struct dlm_lock_resource *res = NULL;
191 struct md_cluster_info *cinfo = mddev->cluster_info;
193 res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
196 init_waitqueue_head(&res->sync_locking);
197 res->sync_locking_done = false;
198 res->ls = cinfo->lockspace;
200 res->mode = DLM_LOCK_IV;
201 namelen = strlen(name);
202 res->name = kzalloc(namelen + 1, GFP_KERNEL);
204 pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
207 strlcpy(res->name, name, namelen + 1);
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);
214 res->flags = DLM_LKF_VALBLK;
220 res->flags |= DLM_LKF_EXPEDITE;
222 ret = dlm_lock_sync(res, DLM_LOCK_NL);
224 pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
227 res->flags &= ~DLM_LKF_EXPEDITE;
228 res->flags |= DLM_LKF_CONVERT;
232 kfree(res->lksb.sb_lvbptr);
238 static void lockres_free(struct dlm_lock_resource *res)
246 * use FORCEUNLOCK flag, so we can unlock even the lock is on the
247 * waiting or convert queue
249 ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_FORCEUNLOCK,
251 if (unlikely(ret != 0))
252 pr_err("failed to unlock %s return %d\n", res->name, ret);
254 wait_event(res->sync_locking, res->sync_locking_done);
257 kfree(res->lksb.sb_lvbptr);
261 static void add_resync_info(struct dlm_lock_resource *lockres,
262 sector_t lo, sector_t hi)
264 struct resync_info *ri;
266 ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
267 ri->lo = cpu_to_le64(lo);
268 ri->hi = cpu_to_le64(hi);
271 static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
273 struct resync_info ri;
274 struct suspend_info *s = NULL;
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);
281 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
285 s->lo = le64_to_cpu(ri.lo);
287 dlm_unlock_sync(lockres);
292 static void recover_bitmaps(struct md_thread *thread)
294 struct mddev *mddev = thread->mddev;
295 struct md_cluster_info *cinfo = mddev->cluster_info;
296 struct dlm_lock_resource *bm_lockres;
299 struct suspend_info *s, *tmp;
302 while (cinfo->recovery_map) {
303 slot = fls64((u64)cinfo->recovery_map) - 1;
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) {
312 spin_unlock_irq(&cinfo->suspend_lock);
314 snprintf(str, 64, "bitmap%04d", slot);
315 bm_lockres = lockres_init(mddev, str, NULL, 1);
317 pr_err("md-cluster: Cannot initialize bitmaps\n");
321 ret = dlm_lock_sync_interruptible(bm_lockres, DLM_LOCK_PW, mddev);
323 pr_err("md-cluster: Could not DLM lock %s: %d\n",
327 ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
329 pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
333 if (lo < mddev->recovery_cp)
334 mddev->recovery_cp = lo;
335 /* wake up thread to continue resync in case resync
337 if (mddev->recovery_cp != MaxSector) {
338 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
339 md_wakeup_thread(mddev->thread);
343 lockres_free(bm_lockres);
344 clear_bit(slot, &cinfo->recovery_map);
348 static void recover_prep(void *arg)
350 struct mddev *mddev = arg;
351 struct md_cluster_info *cinfo = mddev->cluster_info;
352 set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
355 static void __recover_slot(struct mddev *mddev, int slot)
357 struct md_cluster_info *cinfo = mddev->cluster_info;
359 set_bit(slot, &cinfo->recovery_map);
360 if (!cinfo->recovery_thread) {
361 cinfo->recovery_thread = md_register_thread(recover_bitmaps,
363 if (!cinfo->recovery_thread) {
364 pr_warn("md-cluster: Could not create recovery thread\n");
368 md_wakeup_thread(cinfo->recovery_thread);
371 static void recover_slot(void *arg, struct dlm_slot *slot)
373 struct mddev *mddev = arg;
374 struct md_cluster_info *cinfo = mddev->cluster_info;
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,
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);
385 static void recover_done(void *arg, struct dlm_slot *slots,
386 int num_slots, int our_slot,
389 struct mddev *mddev = arg;
390 struct md_cluster_info *cinfo = mddev->cluster_info;
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);
399 clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
402 /* the ops is called when node join the cluster, and do lock recovery
403 * if node failure occurs */
404 static const struct dlm_lockspace_ops md_ls_ops = {
405 .recover_prep = recover_prep,
406 .recover_slot = recover_slot,
407 .recover_done = recover_done,
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.
415 static void ack_bast(void *arg, int mode)
417 struct dlm_lock_resource *res = arg;
418 struct md_cluster_info *cinfo = res->mddev->cluster_info;
420 if (mode == DLM_LOCK_EX) {
421 if (test_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state))
422 md_wakeup_thread(cinfo->recv_thread);
424 set_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state);
428 static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
430 struct suspend_info *s, *tmp;
432 list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
433 if (slot == s->slot) {
440 static void remove_suspend_info(struct mddev *mddev, int slot)
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);
450 static void process_suspend_info(struct mddev *mddev,
451 int slot, sector_t lo, sector_t hi)
453 struct md_cluster_info *cinfo = mddev->cluster_info;
454 struct suspend_info *s;
457 remove_suspend_info(mddev, slot);
458 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
459 md_wakeup_thread(mddev->thread);
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.
472 * sync_low/hi is used to record the region which
473 * arrived in the previous RESYNCING message,
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,
483 cinfo->sync_low = lo;
486 s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
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);
502 static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
505 struct md_cluster_info *cinfo = mddev->cluster_info;
506 char event_name[] = "EVENT=ADD_DEVICE";
508 char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
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,
520 clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
524 static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
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);
533 static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
535 struct md_rdev *rdev;
538 rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
540 set_bit(ClusterRemove, &rdev->flags);
541 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
542 md_wakeup_thread(mddev->thread);
545 pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
546 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
550 static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
552 struct md_rdev *rdev;
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);
559 pr_warn("%s: %d Could not find disk(%d) which is faulty",
560 __func__, __LINE__, le32_to_cpu(msg->raid_slot));
564 static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
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)))
571 switch (le32_to_cpu(msg->type)) {
572 case METADATA_UPDATED:
573 process_metadata_update(mddev, msg);
576 process_suspend_info(mddev, le32_to_cpu(msg->slot),
577 le64_to_cpu(msg->low),
578 le64_to_cpu(msg->high));
581 process_add_new_disk(mddev, msg);
584 process_remove_disk(mddev, msg);
587 process_readd_disk(mddev, msg);
589 case BITMAP_NEEDS_SYNC:
590 __recover_slot(mddev, le32_to_cpu(msg->slot));
594 pr_warn("%s:%d Received unknown message from %d\n",
595 __func__, __LINE__, msg->slot);
601 * thread for receiving message
603 static void recv_daemon(struct md_thread *thread)
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;
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);
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);
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);
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);
646 * Takes the lock on the TOKEN lock resource so no other
647 * node can communicate while the operation is underway.
649 static int lock_token(struct md_cluster_info *cinfo)
653 error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
655 pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
656 __func__, __LINE__, error);
658 /* Lock the receive sequence */
659 mutex_lock(&cinfo->recv_mutex);
664 * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
666 static int lock_comm(struct md_cluster_info *cinfo)
668 wait_event(cinfo->wait,
669 !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
671 return lock_token(cinfo);
674 static void unlock_comm(struct md_cluster_info *cinfo)
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);
684 * This function performs the actual sending of the message. This function is
685 * usually called after performing the encompassing operation
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
695 static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
698 int slot = cinfo->slot_number - 1;
700 cmsg->slot = cpu_to_le32(slot);
701 /*get EX on Message*/
702 error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
704 pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
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);
713 pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
718 /*up-convert CR to EX on Ack*/
719 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
721 pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
726 /*down-convert EX to CR on Ack*/
727 error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
729 pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
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",
739 /* in case the message can't be released due to some reason */
746 static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
751 ret = __sendmsg(cinfo, cmsg);
756 static int gather_all_resync_info(struct mddev *mddev, int total_slots)
758 struct md_cluster_info *cinfo = mddev->cluster_info;
760 struct dlm_lock_resource *bm_lockres;
761 struct suspend_info *s;
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);
772 if (i == (cinfo->slot_number - 1)) {
773 lockres_free(bm_lockres);
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);
783 pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
785 (unsigned long long) s->lo,
786 (unsigned long long) s->hi, i);
787 spin_lock_irq(&cinfo->suspend_lock);
789 list_add(&s->list, &cinfo->suspend_list);
790 spin_unlock_irq(&cinfo->suspend_lock);
793 lockres_free(bm_lockres);
797 lockres_free(bm_lockres);
801 /* Read the disk bitmap sb and check if it needs recovery */
802 ret = bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
804 pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
805 lockres_free(bm_lockres);
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);
814 lockres_free(bm_lockres);
820 static int join(struct mddev *mddev, int nodes)
822 struct md_cluster_info *cinfo;
826 cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
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);
837 mddev->cluster_info = cinfo;
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);
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);
853 /* Initiate the communication resources */
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");
860 cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
861 if (!cinfo->message_lockres)
863 cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
864 if (!cinfo->token_lockres)
866 cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
867 if (!cinfo->no_new_dev_lockres)
870 ret = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
873 pr_err("md-cluster: can't join cluster to avoid lock issue\n");
876 cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
877 if (!cinfo->ack_lockres) {
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",
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);
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) {
898 if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
899 pr_err("Failed to get bitmap lock\n");
904 cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
905 if (!cinfo->resync_lockres) {
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;
927 static void load_bitmaps(struct mddev *mddev, int total_slots)
929 struct md_cluster_info *cinfo = mddev->cluster_info;
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);
940 static void resync_bitmap(struct mddev *mddev)
942 struct md_cluster_info *cinfo = mddev->cluster_info;
943 struct cluster_msg cmsg = {0};
946 cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
947 err = sendmsg(cinfo, &cmsg);
949 pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
950 __func__, __LINE__, err);
953 static void unlock_all_bitmaps(struct mddev *mddev);
954 static int leave(struct mddev *mddev)
956 struct md_cluster_info *cinfo = mddev->cluster_info;
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);
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);
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
984 static int slot_number(struct mddev *mddev)
986 struct md_cluster_info *cinfo = mddev->cluster_info;
988 return cinfo->slot_number - 1;
992 * Check if the communication is already locked, else lock the communication
994 * If it is already locked, token is in EX mode, and hence lock_token()
995 * should not be called.
997 static int metadata_update_start(struct mddev *mddev)
999 struct md_cluster_info *cinfo = mddev->cluster_info;
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));
1005 /* If token is already locked, return 0 */
1006 if (cinfo->token_lockres->mode == DLM_LOCK_EX)
1009 return lock_token(cinfo);
1012 static int metadata_update_finish(struct mddev *mddev)
1014 struct md_cluster_info *cinfo = mddev->cluster_info;
1015 struct cluster_msg cmsg;
1016 struct md_rdev *rdev;
1020 memset(&cmsg, 0, sizeof(cmsg));
1021 cmsg.type = cpu_to_le32(METADATA_UPDATED);
1022 /* Pick up a good active device number to send.
1024 rdev_for_each(rdev, mddev)
1025 if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
1026 raid_slot = rdev->desc_nr;
1029 if (raid_slot >= 0) {
1030 cmsg.raid_slot = cpu_to_le32(raid_slot);
1031 ret = __sendmsg(cinfo, &cmsg);
1033 pr_warn("md-cluster: No good device id found to send\n");
1034 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1039 static void metadata_update_cancel(struct mddev *mddev)
1041 struct md_cluster_info *cinfo = mddev->cluster_info;
1042 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1046 static int resync_start(struct mddev *mddev)
1048 struct md_cluster_info *cinfo = mddev->cluster_info;
1049 return dlm_lock_sync_interruptible(cinfo->resync_lockres, DLM_LOCK_EX, mddev);
1052 static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
1054 struct md_cluster_info *cinfo = mddev->cluster_info;
1055 struct resync_info ri;
1056 struct cluster_msg cmsg = {0};
1058 /* do not send zero again, if we have sent before */
1060 memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
1061 if (le64_to_cpu(ri.hi) == 0)
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);
1072 return sendmsg(cinfo, &cmsg);
1075 static int resync_finish(struct mddev *mddev)
1077 struct md_cluster_info *cinfo = mddev->cluster_info;
1078 dlm_unlock_sync(cinfo->resync_lockres);
1079 return resync_info_update(mddev, 0, 0);
1082 static int area_resyncing(struct mddev *mddev, int direction,
1083 sector_t lo, sector_t hi)
1085 struct md_cluster_info *cinfo = mddev->cluster_info;
1087 struct suspend_info *s;
1089 if ((direction == READ) &&
1090 test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
1093 spin_lock_irq(&cinfo->suspend_lock);
1094 if (list_empty(&cinfo->suspend_list))
1096 list_for_each_entry(s, &cinfo->suspend_list, list)
1097 if (hi > s->lo && lo < s->hi) {
1102 spin_unlock_irq(&cinfo->suspend_lock);
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
1110 static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
1112 struct md_cluster_info *cinfo = mddev->cluster_info;
1113 struct cluster_msg cmsg;
1115 struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1116 char *uuid = sb->device_uuid;
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);
1123 ret = __sendmsg(cinfo, &cmsg);
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 */
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
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.
1145 * For other failure cases, metadata_update_cancel and
1146 * add_new_disk_cancel also clear below bit as well.
1148 set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1149 wake_up(&cinfo->wait);
1154 static void add_new_disk_cancel(struct mddev *mddev)
1156 struct md_cluster_info *cinfo = mddev->cluster_info;
1157 clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1161 static int new_disk_ack(struct mddev *mddev, bool ack)
1163 struct md_cluster_info *cinfo = mddev->cluster_info;
1165 if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
1166 pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
1171 dlm_unlock_sync(cinfo->no_new_dev_lockres);
1172 complete(&cinfo->newdisk_completion);
1176 static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
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);
1185 static int lock_all_bitmaps(struct mddev *mddev)
1187 int slot, my_slot, ret, held = 1, i = 0;
1189 struct md_cluster_info *cinfo = mddev->cluster_info;
1191 cinfo->other_bitmap_lockres = kzalloc((mddev->bitmap_info.nodes - 1) *
1192 sizeof(struct dlm_lock_resource *),
1194 if (!cinfo->other_bitmap_lockres) {
1195 pr_err("md: can't alloc mem for other bitmap locks\n");
1199 my_slot = slot_number(mddev);
1200 for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
1201 if (slot == my_slot)
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])
1210 cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
1211 ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
1220 static void unlock_all_bitmaps(struct mddev *mddev)
1222 struct md_cluster_info *cinfo = mddev->cluster_info;
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]);
1232 kfree(cinfo->other_bitmap_lockres);
1236 static int gather_bitmaps(struct md_rdev *rdev)
1240 struct cluster_msg cmsg = {0};
1241 struct mddev *mddev = rdev->mddev;
1242 struct md_cluster_info *cinfo = mddev->cluster_info;
1244 cmsg.type = cpu_to_le32(RE_ADD);
1245 cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1246 err = sendmsg(cinfo, &cmsg);
1250 for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
1251 if (sn == (cinfo->slot_number - 1))
1253 err = bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
1255 pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
1258 if ((hi > 0) && (lo < mddev->recovery_cp))
1259 mddev->recovery_cp = lo;
1265 static struct md_cluster_operations cluster_ops = {
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,
1286 static int __init cluster_init(void)
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);
1294 static void cluster_exit(void)
1296 unregister_md_cluster_operations();
1299 module_init(cluster_init);
1300 module_exit(cluster_exit);
1301 MODULE_AUTHOR("SUSE");
1302 MODULE_LICENSE("GPL");
1303 MODULE_DESCRIPTION("Clustering support for MD");