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v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright (C) 2015, SUSE
 
 
 
 
 
 
   4 */
   5
   6
   7#include <linux/module.h>
   8#include <linux/kthread.h>
   9#include <linux/dlm.h>
  10#include <linux/sched.h>
  11#include <linux/raid/md_p.h>
  12#include "md.h"
  13#include "md-bitmap.h"
  14#include "md-cluster.h"
  15
  16#define LVB_SIZE	64
  17#define NEW_DEV_TIMEOUT 5000
  18
  19struct dlm_lock_resource {
  20	dlm_lockspace_t *ls;
  21	struct dlm_lksb lksb;
  22	char *name; /* lock name. */
  23	uint32_t flags; /* flags to pass to dlm_lock() */
  24	wait_queue_head_t sync_locking; /* wait queue for synchronized locking */
  25	bool sync_locking_done;
  26	void (*bast)(void *arg, int mode); /* blocking AST function pointer*/
  27	struct mddev *mddev; /* pointing back to mddev. */
  28	int mode;
  29};
  30
 
 
 
 
 
 
 
  31struct resync_info {
  32	__le64 lo;
  33	__le64 hi;
  34};
  35
  36/* md_cluster_info flags */
  37#define		MD_CLUSTER_WAITING_FOR_NEWDISK		1
  38#define		MD_CLUSTER_SUSPEND_READ_BALANCING	2
  39#define		MD_CLUSTER_BEGIN_JOIN_CLUSTER		3
  40
  41/* Lock the send communication. This is done through
  42 * bit manipulation as opposed to a mutex in order to
  43 * accommodate lock and hold. See next comment.
  44 */
  45#define		MD_CLUSTER_SEND_LOCK			4
  46/* If cluster operations (such as adding a disk) must lock the
  47 * communication channel, so as to perform extra operations
  48 * (update metadata) and no other operation is allowed on the
  49 * MD. Token needs to be locked and held until the operation
  50 * completes witha md_update_sb(), which would eventually release
  51 * the lock.
  52 */
  53#define		MD_CLUSTER_SEND_LOCKED_ALREADY		5
  54/* We should receive message after node joined cluster and
  55 * set up all the related infos such as bitmap and personality */
  56#define		MD_CLUSTER_ALREADY_IN_CLUSTER		6
  57#define		MD_CLUSTER_PENDING_RECV_EVENT		7
  58#define 	MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD		8
  59
  60struct md_cluster_info {
  61	struct mddev *mddev; /* the md device which md_cluster_info belongs to */
  62	/* dlm lock space and resources for clustered raid. */
  63	dlm_lockspace_t *lockspace;
  64	int slot_number;
  65	struct completion completion;
  66	struct mutex recv_mutex;
  67	struct dlm_lock_resource *bitmap_lockres;
  68	struct dlm_lock_resource **other_bitmap_lockres;
  69	struct dlm_lock_resource *resync_lockres;
  70	struct list_head suspend_list;
  71
  72	spinlock_t suspend_lock;
  73	/* record the region which write should be suspended */
  74	sector_t suspend_lo;
  75	sector_t suspend_hi;
  76	int suspend_from; /* the slot which broadcast suspend_lo/hi */
  77
  78	struct md_thread *recovery_thread;
  79	unsigned long recovery_map;
  80	/* communication loc resources */
  81	struct dlm_lock_resource *ack_lockres;
  82	struct dlm_lock_resource *message_lockres;
  83	struct dlm_lock_resource *token_lockres;
  84	struct dlm_lock_resource *no_new_dev_lockres;
  85	struct md_thread *recv_thread;
  86	struct completion newdisk_completion;
  87	wait_queue_head_t wait;
  88	unsigned long state;
  89	/* record the region in RESYNCING message */
  90	sector_t sync_low;
  91	sector_t sync_hi;
  92};
  93
  94enum msg_type {
  95	METADATA_UPDATED = 0,
  96	RESYNCING,
  97	NEWDISK,
  98	REMOVE,
  99	RE_ADD,
 100	BITMAP_NEEDS_SYNC,
 101	CHANGE_CAPACITY,
 102	BITMAP_RESIZE,
 103};
 104
 105struct cluster_msg {
 106	__le32 type;
 107	__le32 slot;
 108	/* TODO: Unionize this for smaller footprint */
 109	__le64 low;
 110	__le64 high;
 111	char uuid[16];
 112	__le32 raid_slot;
 113};
 114
 115static void sync_ast(void *arg)
 116{
 117	struct dlm_lock_resource *res;
 118
 119	res = arg;
 120	res->sync_locking_done = true;
 121	wake_up(&res->sync_locking);
 122}
 123
 124static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
 125{
 126	int ret = 0;
 127
 128	ret = dlm_lock(res->ls, mode, &res->lksb,
 129			res->flags, res->name, strlen(res->name),
 130			0, sync_ast, res, res->bast);
 131	if (ret)
 132		return ret;
 133	wait_event(res->sync_locking, res->sync_locking_done);
 134	res->sync_locking_done = false;
 135	if (res->lksb.sb_status == 0)
 136		res->mode = mode;
 137	return res->lksb.sb_status;
 138}
 139
 140static int dlm_unlock_sync(struct dlm_lock_resource *res)
 141{
 142	return dlm_lock_sync(res, DLM_LOCK_NL);
 143}
 144
 145/*
 146 * An variation of dlm_lock_sync, which make lock request could
 147 * be interrupted
 148 */
 149static int dlm_lock_sync_interruptible(struct dlm_lock_resource *res, int mode,
 150				       struct mddev *mddev)
 151{
 152	int ret = 0;
 153
 154	ret = dlm_lock(res->ls, mode, &res->lksb,
 155			res->flags, res->name, strlen(res->name),
 156			0, sync_ast, res, res->bast);
 157	if (ret)
 158		return ret;
 159
 160	wait_event(res->sync_locking, res->sync_locking_done
 161				      || kthread_should_stop()
 162				      || test_bit(MD_CLOSING, &mddev->flags));
 163	if (!res->sync_locking_done) {
 164		/*
 165		 * the convert queue contains the lock request when request is
 166		 * interrupted, and sync_ast could still be run, so need to
 167		 * cancel the request and reset completion
 168		 */
 169		ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_CANCEL,
 170			&res->lksb, res);
 171		res->sync_locking_done = false;
 172		if (unlikely(ret != 0))
 173			pr_info("failed to cancel previous lock request "
 174				 "%s return %d\n", res->name, ret);
 175		return -EPERM;
 176	} else
 177		res->sync_locking_done = false;
 178	if (res->lksb.sb_status == 0)
 179		res->mode = mode;
 180	return res->lksb.sb_status;
 181}
 182
 183static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
 184		char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
 185{
 186	struct dlm_lock_resource *res = NULL;
 187	int ret, namelen;
 188	struct md_cluster_info *cinfo = mddev->cluster_info;
 189
 190	res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
 191	if (!res)
 192		return NULL;
 193	init_waitqueue_head(&res->sync_locking);
 194	res->sync_locking_done = false;
 195	res->ls = cinfo->lockspace;
 196	res->mddev = mddev;
 197	res->mode = DLM_LOCK_IV;
 198	namelen = strlen(name);
 199	res->name = kzalloc(namelen + 1, GFP_KERNEL);
 200	if (!res->name) {
 201		pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
 202		goto out_err;
 203	}
 204	strscpy(res->name, name, namelen + 1);
 205	if (with_lvb) {
 206		res->lksb.sb_lvbptr = kzalloc(LVB_SIZE, GFP_KERNEL);
 207		if (!res->lksb.sb_lvbptr) {
 208			pr_err("md-cluster: Unable to allocate LVB for resource %s\n", name);
 209			goto out_err;
 210		}
 211		res->flags = DLM_LKF_VALBLK;
 212	}
 213
 214	if (bastfn)
 215		res->bast = bastfn;
 216
 217	res->flags |= DLM_LKF_EXPEDITE;
 218
 219	ret = dlm_lock_sync(res, DLM_LOCK_NL);
 220	if (ret) {
 221		pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
 222		goto out_err;
 223	}
 224	res->flags &= ~DLM_LKF_EXPEDITE;
 225	res->flags |= DLM_LKF_CONVERT;
 226
 227	return res;
 228out_err:
 229	kfree(res->lksb.sb_lvbptr);
 230	kfree(res->name);
 231	kfree(res);
 232	return NULL;
 233}
 234
 235static void lockres_free(struct dlm_lock_resource *res)
 236{
 237	int ret = 0;
 238
 239	if (!res)
 240		return;
 241
 242	/*
 243	 * use FORCEUNLOCK flag, so we can unlock even the lock is on the
 244	 * waiting or convert queue
 245	 */
 246	ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_FORCEUNLOCK,
 247		&res->lksb, res);
 248	if (unlikely(ret != 0))
 249		pr_err("failed to unlock %s return %d\n", res->name, ret);
 250	else
 251		wait_event(res->sync_locking, res->sync_locking_done);
 252
 253	kfree(res->name);
 254	kfree(res->lksb.sb_lvbptr);
 255	kfree(res);
 256}
 257
 258static void add_resync_info(struct dlm_lock_resource *lockres,
 259			    sector_t lo, sector_t hi)
 260{
 261	struct resync_info *ri;
 262
 263	ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
 264	ri->lo = cpu_to_le64(lo);
 265	ri->hi = cpu_to_le64(hi);
 266}
 267
 268static int read_resync_info(struct mddev *mddev,
 269			    struct dlm_lock_resource *lockres)
 270{
 271	struct resync_info ri;
 272	struct md_cluster_info *cinfo = mddev->cluster_info;
 273	int ret = 0;
 274
 275	dlm_lock_sync(lockres, DLM_LOCK_CR);
 276	memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
 277	if (le64_to_cpu(ri.hi) > 0) {
 278		cinfo->suspend_hi = le64_to_cpu(ri.hi);
 279		cinfo->suspend_lo = le64_to_cpu(ri.lo);
 280		ret = 1;
 
 
 
 281	}
 282	dlm_unlock_sync(lockres);
 283	return ret;
 
 284}
 285
 286static void recover_bitmaps(struct md_thread *thread)
 287{
 288	struct mddev *mddev = thread->mddev;
 289	struct md_cluster_info *cinfo = mddev->cluster_info;
 290	struct dlm_lock_resource *bm_lockres;
 291	char str[64];
 292	int slot, ret;
 
 293	sector_t lo, hi;
 294
 295	while (cinfo->recovery_map) {
 296		slot = fls64((u64)cinfo->recovery_map) - 1;
 297
 
 
 
 
 
 
 
 
 
 298		snprintf(str, 64, "bitmap%04d", slot);
 299		bm_lockres = lockres_init(mddev, str, NULL, 1);
 300		if (!bm_lockres) {
 301			pr_err("md-cluster: Cannot initialize bitmaps\n");
 302			goto clear_bit;
 303		}
 304
 305		ret = dlm_lock_sync_interruptible(bm_lockres, DLM_LOCK_PW, mddev);
 306		if (ret) {
 307			pr_err("md-cluster: Could not DLM lock %s: %d\n",
 308					str, ret);
 309			goto clear_bit;
 310		}
 311		ret = md_bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
 312		if (ret) {
 313			pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
 314			goto clear_bit;
 315		}
 316
 317		/* Clear suspend_area associated with the bitmap */
 318		spin_lock_irq(&cinfo->suspend_lock);
 319		cinfo->suspend_hi = 0;
 320		cinfo->suspend_lo = 0;
 321		cinfo->suspend_from = -1;
 322		spin_unlock_irq(&cinfo->suspend_lock);
 323
 324		/* Kick off a reshape if needed */
 325		if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) &&
 326		    test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
 327		    mddev->reshape_position != MaxSector)
 328			md_wakeup_thread(mddev->sync_thread);
 329
 330		if (hi > 0) {
 331			if (lo < mddev->recovery_cp)
 332				mddev->recovery_cp = lo;
 333			/* wake up thread to continue resync in case resync
 334			 * is not finished */
 335			if (mddev->recovery_cp != MaxSector) {
 336				/*
 337				 * clear the REMOTE flag since we will launch
 338				 * resync thread in current node.
 339				 */
 340				clear_bit(MD_RESYNCING_REMOTE,
 341					  &mddev->recovery);
 342				set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 343				md_wakeup_thread(mddev->thread);
 344			}
 345		}
 346clear_bit:
 347		lockres_free(bm_lockres);
 348		clear_bit(slot, &cinfo->recovery_map);
 349	}
 350}
 351
 352static void recover_prep(void *arg)
 353{
 354	struct mddev *mddev = arg;
 355	struct md_cluster_info *cinfo = mddev->cluster_info;
 356	set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
 357}
 358
 359static void __recover_slot(struct mddev *mddev, int slot)
 360{
 361	struct md_cluster_info *cinfo = mddev->cluster_info;
 362
 363	set_bit(slot, &cinfo->recovery_map);
 364	if (!cinfo->recovery_thread) {
 365		cinfo->recovery_thread = md_register_thread(recover_bitmaps,
 366				mddev, "recover");
 367		if (!cinfo->recovery_thread) {
 368			pr_warn("md-cluster: Could not create recovery thread\n");
 369			return;
 370		}
 371	}
 372	md_wakeup_thread(cinfo->recovery_thread);
 373}
 374
 375static void recover_slot(void *arg, struct dlm_slot *slot)
 376{
 377	struct mddev *mddev = arg;
 378	struct md_cluster_info *cinfo = mddev->cluster_info;
 379
 380	pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
 381			mddev->bitmap_info.cluster_name,
 382			slot->nodeid, slot->slot,
 383			cinfo->slot_number);
 384	/* deduct one since dlm slot starts from one while the num of
 385	 * cluster-md begins with 0 */
 386	__recover_slot(mddev, slot->slot - 1);
 387}
 388
 389static void recover_done(void *arg, struct dlm_slot *slots,
 390		int num_slots, int our_slot,
 391		uint32_t generation)
 392{
 393	struct mddev *mddev = arg;
 394	struct md_cluster_info *cinfo = mddev->cluster_info;
 395
 396	cinfo->slot_number = our_slot;
 397	/* completion is only need to be complete when node join cluster,
 398	 * it doesn't need to run during another node's failure */
 399	if (test_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state)) {
 400		complete(&cinfo->completion);
 401		clear_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
 402	}
 403	clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
 404}
 405
 406/* the ops is called when node join the cluster, and do lock recovery
 407 * if node failure occurs */
 408static const struct dlm_lockspace_ops md_ls_ops = {
 409	.recover_prep = recover_prep,
 410	.recover_slot = recover_slot,
 411	.recover_done = recover_done,
 412};
 413
 414/*
 415 * The BAST function for the ack lock resource
 416 * This function wakes up the receive thread in
 417 * order to receive and process the message.
 418 */
 419static void ack_bast(void *arg, int mode)
 420{
 421	struct dlm_lock_resource *res = arg;
 422	struct md_cluster_info *cinfo = res->mddev->cluster_info;
 423
 424	if (mode == DLM_LOCK_EX) {
 425		if (test_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state))
 426			md_wakeup_thread(cinfo->recv_thread);
 427		else
 428			set_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state);
 429	}
 430}
 431
 
 
 
 
 
 
 
 
 
 
 
 
 432static void remove_suspend_info(struct mddev *mddev, int slot)
 433{
 434	struct md_cluster_info *cinfo = mddev->cluster_info;
 435	mddev->pers->quiesce(mddev, 1);
 436	spin_lock_irq(&cinfo->suspend_lock);
 437	cinfo->suspend_hi = 0;
 438	cinfo->suspend_lo = 0;
 439	spin_unlock_irq(&cinfo->suspend_lock);
 440	mddev->pers->quiesce(mddev, 0);
 441}
 442
 
 443static void process_suspend_info(struct mddev *mddev,
 444		int slot, sector_t lo, sector_t hi)
 445{
 446	struct md_cluster_info *cinfo = mddev->cluster_info;
 447	struct mdp_superblock_1 *sb = NULL;
 448	struct md_rdev *rdev;
 449
 450	if (!hi) {
 451		/*
 452		 * clear the REMOTE flag since resync or recovery is finished
 453		 * in remote node.
 454		 */
 455		clear_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
 456		remove_suspend_info(mddev, slot);
 457		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 458		md_wakeup_thread(mddev->thread);
 459		return;
 460	}
 461
 462	rdev_for_each(rdev, mddev)
 463		if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
 464			sb = page_address(rdev->sb_page);
 465			break;
 466		}
 467
 468	/*
 469	 * The bitmaps are not same for different nodes
 470	 * if RESYNCING is happening in one node, then
 471	 * the node which received the RESYNCING message
 472	 * probably will perform resync with the region
 473	 * [lo, hi] again, so we could reduce resync time
 474	 * a lot if we can ensure that the bitmaps among
 475	 * different nodes are match up well.
 476	 *
 477	 * sync_low/hi is used to record the region which
 478	 * arrived in the previous RESYNCING message,
 479	 *
 480	 * Call md_bitmap_sync_with_cluster to clear NEEDED_MASK
 481	 * and set RESYNC_MASK since  resync thread is running
 482	 * in another node, so we don't need to do the resync
 483	 * again with the same section.
 484	 *
 485	 * Skip md_bitmap_sync_with_cluster in case reshape
 486	 * happening, because reshaping region is small and
 487	 * we don't want to trigger lots of WARN.
 488	 */
 489	if (sb && !(le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE))
 490		md_bitmap_sync_with_cluster(mddev, cinfo->sync_low,
 491					    cinfo->sync_hi, lo, hi);
 492	cinfo->sync_low = lo;
 493	cinfo->sync_hi = hi;
 494
 
 
 
 
 
 
 495	mddev->pers->quiesce(mddev, 1);
 496	spin_lock_irq(&cinfo->suspend_lock);
 497	cinfo->suspend_from = slot;
 498	cinfo->suspend_lo = lo;
 499	cinfo->suspend_hi = hi;
 500	spin_unlock_irq(&cinfo->suspend_lock);
 501	mddev->pers->quiesce(mddev, 0);
 502}
 503
 504static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
 505{
 506	char disk_uuid[64];
 507	struct md_cluster_info *cinfo = mddev->cluster_info;
 508	char event_name[] = "EVENT=ADD_DEVICE";
 509	char raid_slot[16];
 510	char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
 511	int len;
 512
 513	len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
 514	sprintf(disk_uuid + len, "%pU", cmsg->uuid);
 515	snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
 516	pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
 517	init_completion(&cinfo->newdisk_completion);
 518	set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
 519	kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
 520	wait_for_completion_timeout(&cinfo->newdisk_completion,
 521			NEW_DEV_TIMEOUT);
 522	clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
 523}
 524
 525
 526static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
 527{
 528	int got_lock = 0;
 529	struct md_cluster_info *cinfo = mddev->cluster_info;
 530	mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
 531
 532	dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
 533	wait_event(mddev->thread->wqueue,
 534		   (got_lock = mddev_trylock(mddev)) ||
 535		    test_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state));
 536	md_reload_sb(mddev, mddev->good_device_nr);
 537	if (got_lock)
 538		mddev_unlock(mddev);
 539}
 540
 541static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
 542{
 543	struct md_rdev *rdev;
 544
 545	rcu_read_lock();
 546	rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
 547	if (rdev) {
 548		set_bit(ClusterRemove, &rdev->flags);
 549		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 550		md_wakeup_thread(mddev->thread);
 551	}
 552	else
 553		pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
 554			__func__, __LINE__, le32_to_cpu(msg->raid_slot));
 555	rcu_read_unlock();
 556}
 557
 558static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
 559{
 560	struct md_rdev *rdev;
 561
 562	rcu_read_lock();
 563	rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
 564	if (rdev && test_bit(Faulty, &rdev->flags))
 565		clear_bit(Faulty, &rdev->flags);
 566	else
 567		pr_warn("%s: %d Could not find disk(%d) which is faulty",
 568			__func__, __LINE__, le32_to_cpu(msg->raid_slot));
 569	rcu_read_unlock();
 570}
 571
 572static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
 573{
 574	int ret = 0;
 575
 576	if (WARN(mddev->cluster_info->slot_number - 1 == le32_to_cpu(msg->slot),
 577		"node %d received its own msg\n", le32_to_cpu(msg->slot)))
 578		return -1;
 579	switch (le32_to_cpu(msg->type)) {
 580	case METADATA_UPDATED:
 581		process_metadata_update(mddev, msg);
 582		break;
 583	case CHANGE_CAPACITY:
 584		set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 
 585		break;
 586	case RESYNCING:
 587		set_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
 588		process_suspend_info(mddev, le32_to_cpu(msg->slot),
 589				     le64_to_cpu(msg->low),
 590				     le64_to_cpu(msg->high));
 591		break;
 592	case NEWDISK:
 593		process_add_new_disk(mddev, msg);
 594		break;
 595	case REMOVE:
 596		process_remove_disk(mddev, msg);
 597		break;
 598	case RE_ADD:
 599		process_readd_disk(mddev, msg);
 600		break;
 601	case BITMAP_NEEDS_SYNC:
 602		__recover_slot(mddev, le32_to_cpu(msg->slot));
 603		break;
 604	case BITMAP_RESIZE:
 605		if (le64_to_cpu(msg->high) != mddev->pers->size(mddev, 0, 0))
 606			ret = md_bitmap_resize(mddev->bitmap,
 607					    le64_to_cpu(msg->high), 0, 0);
 608		break;
 609	default:
 610		ret = -1;
 611		pr_warn("%s:%d Received unknown message from %d\n",
 612			__func__, __LINE__, msg->slot);
 613	}
 614	return ret;
 615}
 616
 617/*
 618 * thread for receiving message
 619 */
 620static void recv_daemon(struct md_thread *thread)
 621{
 622	struct md_cluster_info *cinfo = thread->mddev->cluster_info;
 623	struct dlm_lock_resource *ack_lockres = cinfo->ack_lockres;
 624	struct dlm_lock_resource *message_lockres = cinfo->message_lockres;
 625	struct cluster_msg msg;
 626	int ret;
 627
 628	mutex_lock(&cinfo->recv_mutex);
 629	/*get CR on Message*/
 630	if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) {
 631		pr_err("md/raid1:failed to get CR on MESSAGE\n");
 632		mutex_unlock(&cinfo->recv_mutex);
 633		return;
 634	}
 635
 636	/* read lvb and wake up thread to process this message_lockres */
 637	memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg));
 638	ret = process_recvd_msg(thread->mddev, &msg);
 639	if (ret)
 640		goto out;
 641
 642	/*release CR on ack_lockres*/
 643	ret = dlm_unlock_sync(ack_lockres);
 644	if (unlikely(ret != 0))
 645		pr_info("unlock ack failed return %d\n", ret);
 646	/*up-convert to PR on message_lockres*/
 647	ret = dlm_lock_sync(message_lockres, DLM_LOCK_PR);
 648	if (unlikely(ret != 0))
 649		pr_info("lock PR on msg failed return %d\n", ret);
 650	/*get CR on ack_lockres again*/
 651	ret = dlm_lock_sync(ack_lockres, DLM_LOCK_CR);
 652	if (unlikely(ret != 0))
 653		pr_info("lock CR on ack failed return %d\n", ret);
 654out:
 655	/*release CR on message_lockres*/
 656	ret = dlm_unlock_sync(message_lockres);
 657	if (unlikely(ret != 0))
 658		pr_info("unlock msg failed return %d\n", ret);
 659	mutex_unlock(&cinfo->recv_mutex);
 660}
 661
 662/* lock_token()
 663 * Takes the lock on the TOKEN lock resource so no other
 664 * node can communicate while the operation is underway.
 665 */
 666static int lock_token(struct md_cluster_info *cinfo)
 667{
 668	int error;
 669
 670	error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
 671	if (error) {
 672		pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
 673				__func__, __LINE__, error);
 674	} else {
 675		/* Lock the receive sequence */
 676		mutex_lock(&cinfo->recv_mutex);
 677	}
 678	return error;
 679}
 680
 681/* lock_comm()
 682 * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
 683 */
 684static int lock_comm(struct md_cluster_info *cinfo, bool mddev_locked)
 685{
 686	int rv, set_bit = 0;
 687	struct mddev *mddev = cinfo->mddev;
 688
 689	/*
 690	 * If resync thread run after raid1d thread, then process_metadata_update
 691	 * could not continue if raid1d held reconfig_mutex (and raid1d is blocked
 692	 * since another node already got EX on Token and waiting the EX of Ack),
 693	 * so let resync wake up thread in case flag is set.
 694	 */
 695	if (mddev_locked && !test_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
 696				      &cinfo->state)) {
 697		rv = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
 698					      &cinfo->state);
 699		WARN_ON_ONCE(rv);
 700		md_wakeup_thread(mddev->thread);
 701		set_bit = 1;
 702	}
 
 
 
 
 
 
 
 
 
 
 
 
 703
 
 
 
 
 
 704	wait_event(cinfo->wait,
 705		   !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
 706	rv = lock_token(cinfo);
 707	if (set_bit)
 708		clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
 709	return rv;
 710}
 711
 712static void unlock_comm(struct md_cluster_info *cinfo)
 713{
 714	WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
 715	mutex_unlock(&cinfo->recv_mutex);
 716	dlm_unlock_sync(cinfo->token_lockres);
 717	clear_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state);
 718	wake_up(&cinfo->wait);
 719}
 720
 721/* __sendmsg()
 722 * This function performs the actual sending of the message. This function is
 723 * usually called after performing the encompassing operation
 724 * The function:
 725 * 1. Grabs the message lockresource in EX mode
 726 * 2. Copies the message to the message LVB
 727 * 3. Downconverts message lockresource to CW
 728 * 4. Upconverts ack lock resource from CR to EX. This forces the BAST on other nodes
 729 *    and the other nodes read the message. The thread will wait here until all other
 730 *    nodes have released ack lock resource.
 731 * 5. Downconvert ack lockresource to CR
 732 */
 733static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
 734{
 735	int error;
 736	int slot = cinfo->slot_number - 1;
 737
 738	cmsg->slot = cpu_to_le32(slot);
 739	/*get EX on Message*/
 740	error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
 741	if (error) {
 742		pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
 743		goto failed_message;
 744	}
 745
 746	memcpy(cinfo->message_lockres->lksb.sb_lvbptr, (void *)cmsg,
 747			sizeof(struct cluster_msg));
 748	/*down-convert EX to CW on Message*/
 749	error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CW);
 750	if (error) {
 751		pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
 752				error);
 753		goto failed_ack;
 754	}
 755
 756	/*up-convert CR to EX on Ack*/
 757	error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
 758	if (error) {
 759		pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
 760				error);
 761		goto failed_ack;
 762	}
 763
 764	/*down-convert EX to CR on Ack*/
 765	error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
 766	if (error) {
 767		pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
 768				error);
 769		goto failed_ack;
 770	}
 771
 772failed_ack:
 773	error = dlm_unlock_sync(cinfo->message_lockres);
 774	if (unlikely(error != 0)) {
 775		pr_err("md-cluster: failed convert to NL on MESSAGE(%d)\n",
 776			error);
 777		/* in case the message can't be released due to some reason */
 778		goto failed_ack;
 779	}
 780failed_message:
 781	return error;
 782}
 783
 784static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg,
 785		   bool mddev_locked)
 786{
 787	int ret;
 788
 789	ret = lock_comm(cinfo, mddev_locked);
 790	if (!ret) {
 791		ret = __sendmsg(cinfo, cmsg);
 792		unlock_comm(cinfo);
 793	}
 794	return ret;
 795}
 796
 797static int gather_all_resync_info(struct mddev *mddev, int total_slots)
 798{
 799	struct md_cluster_info *cinfo = mddev->cluster_info;
 800	int i, ret = 0;
 801	struct dlm_lock_resource *bm_lockres;
 
 802	char str[64];
 803	sector_t lo, hi;
 804
 805
 806	for (i = 0; i < total_slots; i++) {
 807		memset(str, '\0', 64);
 808		snprintf(str, 64, "bitmap%04d", i);
 809		bm_lockres = lockres_init(mddev, str, NULL, 1);
 810		if (!bm_lockres)
 811			return -ENOMEM;
 812		if (i == (cinfo->slot_number - 1)) {
 813			lockres_free(bm_lockres);
 814			continue;
 815		}
 816
 817		bm_lockres->flags |= DLM_LKF_NOQUEUE;
 818		ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
 819		if (ret == -EAGAIN) {
 820			if (read_resync_info(mddev, bm_lockres)) {
 
 821				pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
 822						__func__, __LINE__,
 823					(unsigned long long) cinfo->suspend_lo,
 824					(unsigned long long) cinfo->suspend_hi,
 825					i);
 826				cinfo->suspend_from = i;
 
 
 827			}
 828			ret = 0;
 829			lockres_free(bm_lockres);
 830			continue;
 831		}
 832		if (ret) {
 833			lockres_free(bm_lockres);
 834			goto out;
 835		}
 836
 837		/* Read the disk bitmap sb and check if it needs recovery */
 838		ret = md_bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
 839		if (ret) {
 840			pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
 841			lockres_free(bm_lockres);
 842			continue;
 843		}
 844		if ((hi > 0) && (lo < mddev->recovery_cp)) {
 845			set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 846			mddev->recovery_cp = lo;
 847			md_check_recovery(mddev);
 848		}
 849
 850		lockres_free(bm_lockres);
 851	}
 852out:
 853	return ret;
 854}
 855
 856static int join(struct mddev *mddev, int nodes)
 857{
 858	struct md_cluster_info *cinfo;
 859	int ret, ops_rv;
 860	char str[64];
 861
 862	cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
 863	if (!cinfo)
 864		return -ENOMEM;
 865
 866	INIT_LIST_HEAD(&cinfo->suspend_list);
 867	spin_lock_init(&cinfo->suspend_lock);
 868	init_completion(&cinfo->completion);
 869	set_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
 870	init_waitqueue_head(&cinfo->wait);
 871	mutex_init(&cinfo->recv_mutex);
 872
 873	mddev->cluster_info = cinfo;
 874	cinfo->mddev = mddev;
 875
 876	memset(str, 0, 64);
 877	sprintf(str, "%pU", mddev->uuid);
 878	ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
 879				0, LVB_SIZE, &md_ls_ops, mddev,
 880				&ops_rv, &cinfo->lockspace);
 881	if (ret)
 882		goto err;
 883	wait_for_completion(&cinfo->completion);
 884	if (nodes < cinfo->slot_number) {
 885		pr_err("md-cluster: Slot allotted(%d) is greater than available slots(%d).",
 886			cinfo->slot_number, nodes);
 887		ret = -ERANGE;
 888		goto err;
 889	}
 890	/* Initiate the communication resources */
 891	ret = -ENOMEM;
 892	cinfo->recv_thread = md_register_thread(recv_daemon, mddev, "cluster_recv");
 893	if (!cinfo->recv_thread) {
 894		pr_err("md-cluster: cannot allocate memory for recv_thread!\n");
 895		goto err;
 896	}
 897	cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
 898	if (!cinfo->message_lockres)
 899		goto err;
 900	cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
 901	if (!cinfo->token_lockres)
 902		goto err;
 903	cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
 904	if (!cinfo->no_new_dev_lockres)
 905		goto err;
 906
 907	ret = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
 908	if (ret) {
 909		ret = -EAGAIN;
 910		pr_err("md-cluster: can't join cluster to avoid lock issue\n");
 911		goto err;
 912	}
 913	cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
 914	if (!cinfo->ack_lockres) {
 915		ret = -ENOMEM;
 916		goto err;
 917	}
 918	/* get sync CR lock on ACK. */
 919	if (dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR))
 920		pr_err("md-cluster: failed to get a sync CR lock on ACK!(%d)\n",
 921				ret);
 922	dlm_unlock_sync(cinfo->token_lockres);
 923	/* get sync CR lock on no-new-dev. */
 924	if (dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR))
 925		pr_err("md-cluster: failed to get a sync CR lock on no-new-dev!(%d)\n", ret);
 926
 927
 928	pr_info("md-cluster: Joined cluster %s slot %d\n", str, cinfo->slot_number);
 929	snprintf(str, 64, "bitmap%04d", cinfo->slot_number - 1);
 930	cinfo->bitmap_lockres = lockres_init(mddev, str, NULL, 1);
 931	if (!cinfo->bitmap_lockres) {
 932		ret = -ENOMEM;
 933		goto err;
 934	}
 935	if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
 936		pr_err("Failed to get bitmap lock\n");
 937		ret = -EINVAL;
 938		goto err;
 939	}
 940
 941	cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
 942	if (!cinfo->resync_lockres) {
 943		ret = -ENOMEM;
 944		goto err;
 945	}
 946
 947	return 0;
 948err:
 949	set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
 950	md_unregister_thread(&cinfo->recovery_thread);
 951	md_unregister_thread(&cinfo->recv_thread);
 952	lockres_free(cinfo->message_lockres);
 953	lockres_free(cinfo->token_lockres);
 954	lockres_free(cinfo->ack_lockres);
 955	lockres_free(cinfo->no_new_dev_lockres);
 956	lockres_free(cinfo->resync_lockres);
 957	lockres_free(cinfo->bitmap_lockres);
 958	if (cinfo->lockspace)
 959		dlm_release_lockspace(cinfo->lockspace, 2);
 960	mddev->cluster_info = NULL;
 961	kfree(cinfo);
 962	return ret;
 963}
 964
 965static void load_bitmaps(struct mddev *mddev, int total_slots)
 966{
 967	struct md_cluster_info *cinfo = mddev->cluster_info;
 968
 969	/* load all the node's bitmap info for resync */
 970	if (gather_all_resync_info(mddev, total_slots))
 971		pr_err("md-cluster: failed to gather all resyn infos\n");
 972	set_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state);
 973	/* wake up recv thread in case something need to be handled */
 974	if (test_and_clear_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state))
 975		md_wakeup_thread(cinfo->recv_thread);
 976}
 977
 978static void resync_bitmap(struct mddev *mddev)
 979{
 980	struct md_cluster_info *cinfo = mddev->cluster_info;
 981	struct cluster_msg cmsg = {0};
 982	int err;
 983
 984	cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
 985	err = sendmsg(cinfo, &cmsg, 1);
 986	if (err)
 987		pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
 988			__func__, __LINE__, err);
 989}
 990
 991static void unlock_all_bitmaps(struct mddev *mddev);
 992static int leave(struct mddev *mddev)
 993{
 994	struct md_cluster_info *cinfo = mddev->cluster_info;
 995
 996	if (!cinfo)
 997		return 0;
 998
 999	/*
1000	 * BITMAP_NEEDS_SYNC message should be sent when node
1001	 * is leaving the cluster with dirty bitmap, also we
1002	 * can only deliver it when dlm connection is available.
1003	 *
1004	 * Also, we should send BITMAP_NEEDS_SYNC message in
1005	 * case reshaping is interrupted.
1006	 */
1007	if ((cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector) ||
1008	    (mddev->reshape_position != MaxSector &&
1009	     test_bit(MD_CLOSING, &mddev->flags)))
1010		resync_bitmap(mddev);
1011
1012	set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
1013	md_unregister_thread(&cinfo->recovery_thread);
1014	md_unregister_thread(&cinfo->recv_thread);
1015	lockres_free(cinfo->message_lockres);
1016	lockres_free(cinfo->token_lockres);
1017	lockres_free(cinfo->ack_lockres);
1018	lockres_free(cinfo->no_new_dev_lockres);
1019	lockres_free(cinfo->resync_lockres);
1020	lockres_free(cinfo->bitmap_lockres);
1021	unlock_all_bitmaps(mddev);
1022	dlm_release_lockspace(cinfo->lockspace, 2);
1023	kfree(cinfo);
1024	return 0;
1025}
1026
1027/* slot_number(): Returns the MD slot number to use
1028 * DLM starts the slot numbers from 1, wheras cluster-md
1029 * wants the number to be from zero, so we deduct one
1030 */
1031static int slot_number(struct mddev *mddev)
1032{
1033	struct md_cluster_info *cinfo = mddev->cluster_info;
1034
1035	return cinfo->slot_number - 1;
1036}
1037
1038/*
1039 * Check if the communication is already locked, else lock the communication
1040 * channel.
1041 * If it is already locked, token is in EX mode, and hence lock_token()
1042 * should not be called.
1043 */
1044static int metadata_update_start(struct mddev *mddev)
1045{
1046	struct md_cluster_info *cinfo = mddev->cluster_info;
1047	int ret;
1048
1049	/*
1050	 * metadata_update_start is always called with the protection of
1051	 * reconfig_mutex, so set WAITING_FOR_TOKEN here.
1052	 */
1053	ret = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
1054				    &cinfo->state);
1055	WARN_ON_ONCE(ret);
1056	md_wakeup_thread(mddev->thread);
1057
1058	wait_event(cinfo->wait,
1059		   !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state) ||
1060		   test_and_clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state));
1061
1062	/* If token is already locked, return 0 */
1063	if (cinfo->token_lockres->mode == DLM_LOCK_EX) {
1064		clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
1065		return 0;
1066	}
1067
1068	ret = lock_token(cinfo);
1069	clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
1070	return ret;
1071}
1072
1073static int metadata_update_finish(struct mddev *mddev)
1074{
1075	struct md_cluster_info *cinfo = mddev->cluster_info;
1076	struct cluster_msg cmsg;
1077	struct md_rdev *rdev;
1078	int ret = 0;
1079	int raid_slot = -1;
1080
1081	memset(&cmsg, 0, sizeof(cmsg));
1082	cmsg.type = cpu_to_le32(METADATA_UPDATED);
1083	/* Pick up a good active device number to send.
1084	 */
1085	rdev_for_each(rdev, mddev)
1086		if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
1087			raid_slot = rdev->desc_nr;
1088			break;
1089		}
1090	if (raid_slot >= 0) {
1091		cmsg.raid_slot = cpu_to_le32(raid_slot);
1092		ret = __sendmsg(cinfo, &cmsg);
1093	} else
1094		pr_warn("md-cluster: No good device id found to send\n");
1095	clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1096	unlock_comm(cinfo);
1097	return ret;
1098}
1099
1100static void metadata_update_cancel(struct mddev *mddev)
1101{
1102	struct md_cluster_info *cinfo = mddev->cluster_info;
1103	clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1104	unlock_comm(cinfo);
1105}
1106
1107static int update_bitmap_size(struct mddev *mddev, sector_t size)
1108{
1109	struct md_cluster_info *cinfo = mddev->cluster_info;
1110	struct cluster_msg cmsg = {0};
1111	int ret;
1112
1113	cmsg.type = cpu_to_le32(BITMAP_RESIZE);
1114	cmsg.high = cpu_to_le64(size);
1115	ret = sendmsg(cinfo, &cmsg, 0);
1116	if (ret)
1117		pr_err("%s:%d: failed to send BITMAP_RESIZE message (%d)\n",
1118			__func__, __LINE__, ret);
1119	return ret;
1120}
1121
1122static int resize_bitmaps(struct mddev *mddev, sector_t newsize, sector_t oldsize)
1123{
1124	struct bitmap_counts *counts;
1125	char str[64];
1126	struct dlm_lock_resource *bm_lockres;
1127	struct bitmap *bitmap = mddev->bitmap;
1128	unsigned long my_pages = bitmap->counts.pages;
1129	int i, rv;
1130
1131	/*
1132	 * We need to ensure all the nodes can grow to a larger
1133	 * bitmap size before make the reshaping.
1134	 */
1135	rv = update_bitmap_size(mddev, newsize);
1136	if (rv)
1137		return rv;
1138
1139	for (i = 0; i < mddev->bitmap_info.nodes; i++) {
1140		if (i == md_cluster_ops->slot_number(mddev))
1141			continue;
1142
1143		bitmap = get_bitmap_from_slot(mddev, i);
1144		if (IS_ERR(bitmap)) {
1145			pr_err("can't get bitmap from slot %d\n", i);
1146			bitmap = NULL;
1147			goto out;
1148		}
1149		counts = &bitmap->counts;
1150
1151		/*
1152		 * If we can hold the bitmap lock of one node then
1153		 * the slot is not occupied, update the pages.
1154		 */
1155		snprintf(str, 64, "bitmap%04d", i);
1156		bm_lockres = lockres_init(mddev, str, NULL, 1);
1157		if (!bm_lockres) {
1158			pr_err("Cannot initialize %s lock\n", str);
1159			goto out;
1160		}
1161		bm_lockres->flags |= DLM_LKF_NOQUEUE;
1162		rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
1163		if (!rv)
1164			counts->pages = my_pages;
1165		lockres_free(bm_lockres);
1166
1167		if (my_pages != counts->pages)
1168			/*
1169			 * Let's revert the bitmap size if one node
1170			 * can't resize bitmap
1171			 */
1172			goto out;
1173		md_bitmap_free(bitmap);
1174	}
1175
1176	return 0;
1177out:
1178	md_bitmap_free(bitmap);
1179	update_bitmap_size(mddev, oldsize);
1180	return -1;
1181}
1182
1183/*
1184 * return 0 if all the bitmaps have the same sync_size
1185 */
1186static int cluster_check_sync_size(struct mddev *mddev)
1187{
1188	int i, rv;
1189	bitmap_super_t *sb;
1190	unsigned long my_sync_size, sync_size = 0;
1191	int node_num = mddev->bitmap_info.nodes;
1192	int current_slot = md_cluster_ops->slot_number(mddev);
1193	struct bitmap *bitmap = mddev->bitmap;
1194	char str[64];
1195	struct dlm_lock_resource *bm_lockres;
1196
1197	sb = kmap_atomic(bitmap->storage.sb_page);
1198	my_sync_size = sb->sync_size;
1199	kunmap_atomic(sb);
1200
1201	for (i = 0; i < node_num; i++) {
1202		if (i == current_slot)
1203			continue;
1204
1205		bitmap = get_bitmap_from_slot(mddev, i);
1206		if (IS_ERR(bitmap)) {
1207			pr_err("can't get bitmap from slot %d\n", i);
1208			return -1;
1209		}
1210
1211		/*
1212		 * If we can hold the bitmap lock of one node then
1213		 * the slot is not occupied, update the sb.
1214		 */
1215		snprintf(str, 64, "bitmap%04d", i);
1216		bm_lockres = lockres_init(mddev, str, NULL, 1);
1217		if (!bm_lockres) {
1218			pr_err("md-cluster: Cannot initialize %s\n", str);
1219			md_bitmap_free(bitmap);
1220			return -1;
1221		}
1222		bm_lockres->flags |= DLM_LKF_NOQUEUE;
1223		rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
1224		if (!rv)
1225			md_bitmap_update_sb(bitmap);
1226		lockres_free(bm_lockres);
1227
1228		sb = kmap_atomic(bitmap->storage.sb_page);
1229		if (sync_size == 0)
1230			sync_size = sb->sync_size;
1231		else if (sync_size != sb->sync_size) {
1232			kunmap_atomic(sb);
1233			md_bitmap_free(bitmap);
1234			return -1;
1235		}
1236		kunmap_atomic(sb);
1237		md_bitmap_free(bitmap);
1238	}
1239
1240	return (my_sync_size == sync_size) ? 0 : -1;
1241}
1242
1243/*
1244 * Update the size for cluster raid is a little more complex, we perform it
1245 * by the steps:
1246 * 1. hold token lock and update superblock in initiator node.
1247 * 2. send METADATA_UPDATED msg to other nodes.
1248 * 3. The initiator node continues to check each bitmap's sync_size, if all
1249 *    bitmaps have the same value of sync_size, then we can set capacity and
1250 *    let other nodes to perform it. If one node can't update sync_size
1251 *    accordingly, we need to revert to previous value.
1252 */
1253static void update_size(struct mddev *mddev, sector_t old_dev_sectors)
1254{
1255	struct md_cluster_info *cinfo = mddev->cluster_info;
1256	struct cluster_msg cmsg;
1257	struct md_rdev *rdev;
1258	int ret = 0;
1259	int raid_slot = -1;
1260
1261	md_update_sb(mddev, 1);
1262	if (lock_comm(cinfo, 1)) {
1263		pr_err("%s: lock_comm failed\n", __func__);
1264		return;
1265	}
1266
1267	memset(&cmsg, 0, sizeof(cmsg));
1268	cmsg.type = cpu_to_le32(METADATA_UPDATED);
1269	rdev_for_each(rdev, mddev)
1270		if (rdev->raid_disk >= 0 && !test_bit(Faulty, &rdev->flags)) {
1271			raid_slot = rdev->desc_nr;
1272			break;
1273		}
1274	if (raid_slot >= 0) {
1275		cmsg.raid_slot = cpu_to_le32(raid_slot);
1276		/*
1277		 * We can only change capiticy after all the nodes can do it,
1278		 * so need to wait after other nodes already received the msg
1279		 * and handled the change
1280		 */
1281		ret = __sendmsg(cinfo, &cmsg);
1282		if (ret) {
1283			pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",
1284			       __func__, __LINE__);
1285			unlock_comm(cinfo);
1286			return;
1287		}
1288	} else {
1289		pr_err("md-cluster: No good device id found to send\n");
1290		unlock_comm(cinfo);
1291		return;
1292	}
1293
1294	/*
1295	 * check the sync_size from other node's bitmap, if sync_size
1296	 * have already updated in other nodes as expected, send an
1297	 * empty metadata msg to permit the change of capacity
1298	 */
1299	if (cluster_check_sync_size(mddev) == 0) {
1300		memset(&cmsg, 0, sizeof(cmsg));
1301		cmsg.type = cpu_to_le32(CHANGE_CAPACITY);
1302		ret = __sendmsg(cinfo, &cmsg);
1303		if (ret)
1304			pr_err("%s:%d: failed to send CHANGE_CAPACITY msg\n",
1305			       __func__, __LINE__);
1306		set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 
1307	} else {
1308		/* revert to previous sectors */
1309		ret = mddev->pers->resize(mddev, old_dev_sectors);
 
 
1310		ret = __sendmsg(cinfo, &cmsg);
1311		if (ret)
1312			pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",
1313			       __func__, __LINE__);
1314	}
1315	unlock_comm(cinfo);
1316}
1317
1318static int resync_start(struct mddev *mddev)
1319{
1320	struct md_cluster_info *cinfo = mddev->cluster_info;
1321	return dlm_lock_sync_interruptible(cinfo->resync_lockres, DLM_LOCK_EX, mddev);
1322}
1323
1324static void resync_info_get(struct mddev *mddev, sector_t *lo, sector_t *hi)
1325{
1326	struct md_cluster_info *cinfo = mddev->cluster_info;
1327
1328	spin_lock_irq(&cinfo->suspend_lock);
1329	*lo = cinfo->suspend_lo;
1330	*hi = cinfo->suspend_hi;
1331	spin_unlock_irq(&cinfo->suspend_lock);
1332}
1333
1334static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
1335{
1336	struct md_cluster_info *cinfo = mddev->cluster_info;
1337	struct resync_info ri;
1338	struct cluster_msg cmsg = {0};
1339
1340	/* do not send zero again, if we have sent before */
1341	if (hi == 0) {
1342		memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
1343		if (le64_to_cpu(ri.hi) == 0)
1344			return 0;
1345	}
1346
1347	add_resync_info(cinfo->bitmap_lockres, lo, hi);
1348	/* Re-acquire the lock to refresh LVB */
1349	dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
1350	cmsg.type = cpu_to_le32(RESYNCING);
1351	cmsg.low = cpu_to_le64(lo);
1352	cmsg.high = cpu_to_le64(hi);
1353
1354	/*
1355	 * mddev_lock is held if resync_info_update is called from
1356	 * resync_finish (md_reap_sync_thread -> resync_finish)
1357	 */
1358	if (lo == 0 && hi == 0)
1359		return sendmsg(cinfo, &cmsg, 1);
1360	else
1361		return sendmsg(cinfo, &cmsg, 0);
1362}
1363
1364static int resync_finish(struct mddev *mddev)
1365{
1366	struct md_cluster_info *cinfo = mddev->cluster_info;
1367	int ret = 0;
1368
1369	clear_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
1370
1371	/*
1372	 * If resync thread is interrupted so we can't say resync is finished,
1373	 * another node will launch resync thread to continue.
1374	 */
1375	if (!test_bit(MD_CLOSING, &mddev->flags))
1376		ret = resync_info_update(mddev, 0, 0);
1377	dlm_unlock_sync(cinfo->resync_lockres);
1378	return ret;
1379}
1380
1381static int area_resyncing(struct mddev *mddev, int direction,
1382		sector_t lo, sector_t hi)
1383{
1384	struct md_cluster_info *cinfo = mddev->cluster_info;
1385	int ret = 0;
 
1386
1387	if ((direction == READ) &&
1388		test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
1389		return 1;
1390
1391	spin_lock_irq(&cinfo->suspend_lock);
1392	if (hi > cinfo->suspend_lo && lo < cinfo->suspend_hi)
1393		ret = 1;
 
 
 
 
 
 
1394	spin_unlock_irq(&cinfo->suspend_lock);
1395	return ret;
1396}
1397
1398/* add_new_disk() - initiates a disk add
1399 * However, if this fails before writing md_update_sb(),
1400 * add_new_disk_cancel() must be called to release token lock
1401 */
1402static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
1403{
1404	struct md_cluster_info *cinfo = mddev->cluster_info;
1405	struct cluster_msg cmsg;
1406	int ret = 0;
1407	struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1408	char *uuid = sb->device_uuid;
1409
1410	memset(&cmsg, 0, sizeof(cmsg));
1411	cmsg.type = cpu_to_le32(NEWDISK);
1412	memcpy(cmsg.uuid, uuid, 16);
1413	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1414	if (lock_comm(cinfo, 1))
1415		return -EAGAIN;
1416	ret = __sendmsg(cinfo, &cmsg);
1417	if (ret) {
1418		unlock_comm(cinfo);
1419		return ret;
1420	}
1421	cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
1422	ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
1423	cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;
1424	/* Some node does not "see" the device */
1425	if (ret == -EAGAIN)
1426		ret = -ENOENT;
1427	if (ret)
1428		unlock_comm(cinfo);
1429	else {
1430		dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
1431		/* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
1432		 * will run soon after add_new_disk, the below path will be
1433		 * invoked:
1434		 *   md_wakeup_thread(mddev->thread)
1435		 *	-> conf->thread (raid1d)
1436		 *	-> md_check_recovery -> md_update_sb
1437		 *	-> metadata_update_start/finish
1438		 * MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
1439		 *
1440		 * For other failure cases, metadata_update_cancel and
1441		 * add_new_disk_cancel also clear below bit as well.
1442		 * */
1443		set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1444		wake_up(&cinfo->wait);
1445	}
1446	return ret;
1447}
1448
1449static void add_new_disk_cancel(struct mddev *mddev)
1450{
1451	struct md_cluster_info *cinfo = mddev->cluster_info;
1452	clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1453	unlock_comm(cinfo);
1454}
1455
1456static int new_disk_ack(struct mddev *mddev, bool ack)
1457{
1458	struct md_cluster_info *cinfo = mddev->cluster_info;
1459
1460	if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
1461		pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
1462		return -EINVAL;
1463	}
1464
1465	if (ack)
1466		dlm_unlock_sync(cinfo->no_new_dev_lockres);
1467	complete(&cinfo->newdisk_completion);
1468	return 0;
1469}
1470
1471static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1472{
1473	struct cluster_msg cmsg = {0};
1474	struct md_cluster_info *cinfo = mddev->cluster_info;
1475	cmsg.type = cpu_to_le32(REMOVE);
1476	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1477	return sendmsg(cinfo, &cmsg, 1);
1478}
1479
1480static int lock_all_bitmaps(struct mddev *mddev)
1481{
1482	int slot, my_slot, ret, held = 1, i = 0;
1483	char str[64];
1484	struct md_cluster_info *cinfo = mddev->cluster_info;
1485
1486	cinfo->other_bitmap_lockres =
1487		kcalloc(mddev->bitmap_info.nodes - 1,
1488			sizeof(struct dlm_lock_resource *), GFP_KERNEL);
1489	if (!cinfo->other_bitmap_lockres) {
1490		pr_err("md: can't alloc mem for other bitmap locks\n");
1491		return 0;
1492	}
1493
1494	my_slot = slot_number(mddev);
1495	for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
1496		if (slot == my_slot)
1497			continue;
1498
1499		memset(str, '\0', 64);
1500		snprintf(str, 64, "bitmap%04d", slot);
1501		cinfo->other_bitmap_lockres[i] = lockres_init(mddev, str, NULL, 1);
1502		if (!cinfo->other_bitmap_lockres[i])
1503			return -ENOMEM;
1504
1505		cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
1506		ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
1507		if (ret)
1508			held = -1;
1509		i++;
1510	}
1511
1512	return held;
1513}
1514
1515static void unlock_all_bitmaps(struct mddev *mddev)
1516{
1517	struct md_cluster_info *cinfo = mddev->cluster_info;
1518	int i;
1519
1520	/* release other node's bitmap lock if they are existed */
1521	if (cinfo->other_bitmap_lockres) {
1522		for (i = 0; i < mddev->bitmap_info.nodes - 1; i++) {
1523			if (cinfo->other_bitmap_lockres[i]) {
1524				lockres_free(cinfo->other_bitmap_lockres[i]);
1525			}
1526		}
1527		kfree(cinfo->other_bitmap_lockres);
1528		cinfo->other_bitmap_lockres = NULL;
1529	}
1530}
1531
1532static int gather_bitmaps(struct md_rdev *rdev)
1533{
1534	int sn, err;
1535	sector_t lo, hi;
1536	struct cluster_msg cmsg = {0};
1537	struct mddev *mddev = rdev->mddev;
1538	struct md_cluster_info *cinfo = mddev->cluster_info;
1539
1540	cmsg.type = cpu_to_le32(RE_ADD);
1541	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1542	err = sendmsg(cinfo, &cmsg, 1);
1543	if (err)
1544		goto out;
1545
1546	for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
1547		if (sn == (cinfo->slot_number - 1))
1548			continue;
1549		err = md_bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
1550		if (err) {
1551			pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
1552			goto out;
1553		}
1554		if ((hi > 0) && (lo < mddev->recovery_cp))
1555			mddev->recovery_cp = lo;
1556	}
1557out:
1558	return err;
1559}
1560
1561static struct md_cluster_operations cluster_ops = {
1562	.join   = join,
1563	.leave  = leave,
1564	.slot_number = slot_number,
1565	.resync_start = resync_start,
1566	.resync_finish = resync_finish,
1567	.resync_info_update = resync_info_update,
1568	.resync_info_get = resync_info_get,
1569	.metadata_update_start = metadata_update_start,
1570	.metadata_update_finish = metadata_update_finish,
1571	.metadata_update_cancel = metadata_update_cancel,
1572	.area_resyncing = area_resyncing,
1573	.add_new_disk = add_new_disk,
1574	.add_new_disk_cancel = add_new_disk_cancel,
1575	.new_disk_ack = new_disk_ack,
1576	.remove_disk = remove_disk,
1577	.load_bitmaps = load_bitmaps,
1578	.gather_bitmaps = gather_bitmaps,
1579	.resize_bitmaps = resize_bitmaps,
1580	.lock_all_bitmaps = lock_all_bitmaps,
1581	.unlock_all_bitmaps = unlock_all_bitmaps,
1582	.update_size = update_size,
1583};
1584
1585static int __init cluster_init(void)
1586{
1587	pr_warn("md-cluster: support raid1 and raid10 (limited support)\n");
1588	pr_info("Registering Cluster MD functions\n");
1589	register_md_cluster_operations(&cluster_ops, THIS_MODULE);
1590	return 0;
1591}
1592
1593static void cluster_exit(void)
1594{
1595	unregister_md_cluster_operations();
1596}
1597
1598module_init(cluster_init);
1599module_exit(cluster_exit);
1600MODULE_AUTHOR("SUSE");
1601MODULE_LICENSE("GPL");
1602MODULE_DESCRIPTION("Clustering support for MD");
v4.17
 
   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 "md-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#define 	MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD		8
  71
  72struct md_cluster_info {
  73	struct mddev *mddev; /* the md device which md_cluster_info belongs to */
  74	/* dlm lock space and resources for clustered raid. */
  75	dlm_lockspace_t *lockspace;
  76	int slot_number;
  77	struct completion completion;
  78	struct mutex recv_mutex;
  79	struct dlm_lock_resource *bitmap_lockres;
  80	struct dlm_lock_resource **other_bitmap_lockres;
  81	struct dlm_lock_resource *resync_lockres;
  82	struct list_head suspend_list;
 
  83	spinlock_t suspend_lock;
 
 
 
 
 
  84	struct md_thread *recovery_thread;
  85	unsigned long recovery_map;
  86	/* communication loc resources */
  87	struct dlm_lock_resource *ack_lockres;
  88	struct dlm_lock_resource *message_lockres;
  89	struct dlm_lock_resource *token_lockres;
  90	struct dlm_lock_resource *no_new_dev_lockres;
  91	struct md_thread *recv_thread;
  92	struct completion newdisk_completion;
  93	wait_queue_head_t wait;
  94	unsigned long state;
  95	/* record the region in RESYNCING message */
  96	sector_t sync_low;
  97	sector_t sync_hi;
  98};
  99
 100enum msg_type {
 101	METADATA_UPDATED = 0,
 102	RESYNCING,
 103	NEWDISK,
 104	REMOVE,
 105	RE_ADD,
 106	BITMAP_NEEDS_SYNC,
 107	CHANGE_CAPACITY,
 
 108};
 109
 110struct cluster_msg {
 111	__le32 type;
 112	__le32 slot;
 113	/* TODO: Unionize this for smaller footprint */
 114	__le64 low;
 115	__le64 high;
 116	char uuid[16];
 117	__le32 raid_slot;
 118};
 119
 120static void sync_ast(void *arg)
 121{
 122	struct dlm_lock_resource *res;
 123
 124	res = arg;
 125	res->sync_locking_done = true;
 126	wake_up(&res->sync_locking);
 127}
 128
 129static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
 130{
 131	int ret = 0;
 132
 133	ret = dlm_lock(res->ls, mode, &res->lksb,
 134			res->flags, res->name, strlen(res->name),
 135			0, sync_ast, res, res->bast);
 136	if (ret)
 137		return ret;
 138	wait_event(res->sync_locking, res->sync_locking_done);
 139	res->sync_locking_done = false;
 140	if (res->lksb.sb_status == 0)
 141		res->mode = mode;
 142	return res->lksb.sb_status;
 143}
 144
 145static int dlm_unlock_sync(struct dlm_lock_resource *res)
 146{
 147	return dlm_lock_sync(res, DLM_LOCK_NL);
 148}
 149
 150/*
 151 * An variation of dlm_lock_sync, which make lock request could
 152 * be interrupted
 153 */
 154static int dlm_lock_sync_interruptible(struct dlm_lock_resource *res, int mode,
 155				       struct mddev *mddev)
 156{
 157	int ret = 0;
 158
 159	ret = dlm_lock(res->ls, mode, &res->lksb,
 160			res->flags, res->name, strlen(res->name),
 161			0, sync_ast, res, res->bast);
 162	if (ret)
 163		return ret;
 164
 165	wait_event(res->sync_locking, res->sync_locking_done
 166				      || kthread_should_stop()
 167				      || test_bit(MD_CLOSING, &mddev->flags));
 168	if (!res->sync_locking_done) {
 169		/*
 170		 * the convert queue contains the lock request when request is
 171		 * interrupted, and sync_ast could still be run, so need to
 172		 * cancel the request and reset completion
 173		 */
 174		ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_CANCEL,
 175			&res->lksb, res);
 176		res->sync_locking_done = false;
 177		if (unlikely(ret != 0))
 178			pr_info("failed to cancel previous lock request "
 179				 "%s return %d\n", res->name, ret);
 180		return -EPERM;
 181	} else
 182		res->sync_locking_done = false;
 183	if (res->lksb.sb_status == 0)
 184		res->mode = mode;
 185	return res->lksb.sb_status;
 186}
 187
 188static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
 189		char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
 190{
 191	struct dlm_lock_resource *res = NULL;
 192	int ret, namelen;
 193	struct md_cluster_info *cinfo = mddev->cluster_info;
 194
 195	res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
 196	if (!res)
 197		return NULL;
 198	init_waitqueue_head(&res->sync_locking);
 199	res->sync_locking_done = false;
 200	res->ls = cinfo->lockspace;
 201	res->mddev = mddev;
 202	res->mode = DLM_LOCK_IV;
 203	namelen = strlen(name);
 204	res->name = kzalloc(namelen + 1, GFP_KERNEL);
 205	if (!res->name) {
 206		pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
 207		goto out_err;
 208	}
 209	strlcpy(res->name, name, namelen + 1);
 210	if (with_lvb) {
 211		res->lksb.sb_lvbptr = kzalloc(LVB_SIZE, GFP_KERNEL);
 212		if (!res->lksb.sb_lvbptr) {
 213			pr_err("md-cluster: Unable to allocate LVB for resource %s\n", name);
 214			goto out_err;
 215		}
 216		res->flags = DLM_LKF_VALBLK;
 217	}
 218
 219	if (bastfn)
 220		res->bast = bastfn;
 221
 222	res->flags |= DLM_LKF_EXPEDITE;
 223
 224	ret = dlm_lock_sync(res, DLM_LOCK_NL);
 225	if (ret) {
 226		pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
 227		goto out_err;
 228	}
 229	res->flags &= ~DLM_LKF_EXPEDITE;
 230	res->flags |= DLM_LKF_CONVERT;
 231
 232	return res;
 233out_err:
 234	kfree(res->lksb.sb_lvbptr);
 235	kfree(res->name);
 236	kfree(res);
 237	return NULL;
 238}
 239
 240static void lockres_free(struct dlm_lock_resource *res)
 241{
 242	int ret = 0;
 243
 244	if (!res)
 245		return;
 246
 247	/*
 248	 * use FORCEUNLOCK flag, so we can unlock even the lock is on the
 249	 * waiting or convert queue
 250	 */
 251	ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_FORCEUNLOCK,
 252		&res->lksb, res);
 253	if (unlikely(ret != 0))
 254		pr_err("failed to unlock %s return %d\n", res->name, ret);
 255	else
 256		wait_event(res->sync_locking, res->sync_locking_done);
 257
 258	kfree(res->name);
 259	kfree(res->lksb.sb_lvbptr);
 260	kfree(res);
 261}
 262
 263static void add_resync_info(struct dlm_lock_resource *lockres,
 264			    sector_t lo, sector_t hi)
 265{
 266	struct resync_info *ri;
 267
 268	ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
 269	ri->lo = cpu_to_le64(lo);
 270	ri->hi = cpu_to_le64(hi);
 271}
 272
 273static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
 
 274{
 275	struct resync_info ri;
 276	struct suspend_info *s = NULL;
 277	sector_t hi = 0;
 278
 279	dlm_lock_sync(lockres, DLM_LOCK_CR);
 280	memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
 281	hi = le64_to_cpu(ri.hi);
 282	if (hi > 0) {
 283		s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
 284		if (!s)
 285			goto out;
 286		s->hi = hi;
 287		s->lo = le64_to_cpu(ri.lo);
 288	}
 289	dlm_unlock_sync(lockres);
 290out:
 291	return s;
 292}
 293
 294static void recover_bitmaps(struct md_thread *thread)
 295{
 296	struct mddev *mddev = thread->mddev;
 297	struct md_cluster_info *cinfo = mddev->cluster_info;
 298	struct dlm_lock_resource *bm_lockres;
 299	char str[64];
 300	int slot, ret;
 301	struct suspend_info *s, *tmp;
 302	sector_t lo, hi;
 303
 304	while (cinfo->recovery_map) {
 305		slot = fls64((u64)cinfo->recovery_map) - 1;
 306
 307		/* Clear suspend_area associated with the bitmap */
 308		spin_lock_irq(&cinfo->suspend_lock);
 309		list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
 310			if (slot == s->slot) {
 311				list_del(&s->list);
 312				kfree(s);
 313			}
 314		spin_unlock_irq(&cinfo->suspend_lock);
 315
 316		snprintf(str, 64, "bitmap%04d", slot);
 317		bm_lockres = lockres_init(mddev, str, NULL, 1);
 318		if (!bm_lockres) {
 319			pr_err("md-cluster: Cannot initialize bitmaps\n");
 320			goto clear_bit;
 321		}
 322
 323		ret = dlm_lock_sync_interruptible(bm_lockres, DLM_LOCK_PW, mddev);
 324		if (ret) {
 325			pr_err("md-cluster: Could not DLM lock %s: %d\n",
 326					str, ret);
 327			goto clear_bit;
 328		}
 329		ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
 330		if (ret) {
 331			pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
 332			goto clear_bit;
 333		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 334		if (hi > 0) {
 335			if (lo < mddev->recovery_cp)
 336				mddev->recovery_cp = lo;
 337			/* wake up thread to continue resync in case resync
 338			 * is not finished */
 339			if (mddev->recovery_cp != MaxSector) {
 340			    set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 341			    md_wakeup_thread(mddev->thread);
 
 
 
 
 
 
 342			}
 343		}
 344clear_bit:
 345		lockres_free(bm_lockres);
 346		clear_bit(slot, &cinfo->recovery_map);
 347	}
 348}
 349
 350static void recover_prep(void *arg)
 351{
 352	struct mddev *mddev = arg;
 353	struct md_cluster_info *cinfo = mddev->cluster_info;
 354	set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
 355}
 356
 357static void __recover_slot(struct mddev *mddev, int slot)
 358{
 359	struct md_cluster_info *cinfo = mddev->cluster_info;
 360
 361	set_bit(slot, &cinfo->recovery_map);
 362	if (!cinfo->recovery_thread) {
 363		cinfo->recovery_thread = md_register_thread(recover_bitmaps,
 364				mddev, "recover");
 365		if (!cinfo->recovery_thread) {
 366			pr_warn("md-cluster: Could not create recovery thread\n");
 367			return;
 368		}
 369	}
 370	md_wakeup_thread(cinfo->recovery_thread);
 371}
 372
 373static void recover_slot(void *arg, struct dlm_slot *slot)
 374{
 375	struct mddev *mddev = arg;
 376	struct md_cluster_info *cinfo = mddev->cluster_info;
 377
 378	pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
 379			mddev->bitmap_info.cluster_name,
 380			slot->nodeid, slot->slot,
 381			cinfo->slot_number);
 382	/* deduct one since dlm slot starts from one while the num of
 383	 * cluster-md begins with 0 */
 384	__recover_slot(mddev, slot->slot - 1);
 385}
 386
 387static void recover_done(void *arg, struct dlm_slot *slots,
 388		int num_slots, int our_slot,
 389		uint32_t generation)
 390{
 391	struct mddev *mddev = arg;
 392	struct md_cluster_info *cinfo = mddev->cluster_info;
 393
 394	cinfo->slot_number = our_slot;
 395	/* completion is only need to be complete when node join cluster,
 396	 * it doesn't need to run during another node's failure */
 397	if (test_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state)) {
 398		complete(&cinfo->completion);
 399		clear_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
 400	}
 401	clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
 402}
 403
 404/* the ops is called when node join the cluster, and do lock recovery
 405 * if node failure occurs */
 406static const struct dlm_lockspace_ops md_ls_ops = {
 407	.recover_prep = recover_prep,
 408	.recover_slot = recover_slot,
 409	.recover_done = recover_done,
 410};
 411
 412/*
 413 * The BAST function for the ack lock resource
 414 * This function wakes up the receive thread in
 415 * order to receive and process the message.
 416 */
 417static void ack_bast(void *arg, int mode)
 418{
 419	struct dlm_lock_resource *res = arg;
 420	struct md_cluster_info *cinfo = res->mddev->cluster_info;
 421
 422	if (mode == DLM_LOCK_EX) {
 423		if (test_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state))
 424			md_wakeup_thread(cinfo->recv_thread);
 425		else
 426			set_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state);
 427	}
 428}
 429
 430static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
 431{
 432	struct suspend_info *s, *tmp;
 433
 434	list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
 435		if (slot == s->slot) {
 436			list_del(&s->list);
 437			kfree(s);
 438			break;
 439		}
 440}
 441
 442static void remove_suspend_info(struct mddev *mddev, int slot)
 443{
 444	struct md_cluster_info *cinfo = mddev->cluster_info;
 445	mddev->pers->quiesce(mddev, 1);
 446	spin_lock_irq(&cinfo->suspend_lock);
 447	__remove_suspend_info(cinfo, slot);
 
 448	spin_unlock_irq(&cinfo->suspend_lock);
 449	mddev->pers->quiesce(mddev, 0);
 450}
 451
 452
 453static void process_suspend_info(struct mddev *mddev,
 454		int slot, sector_t lo, sector_t hi)
 455{
 456	struct md_cluster_info *cinfo = mddev->cluster_info;
 457	struct suspend_info *s;
 
 458
 459	if (!hi) {
 
 
 
 
 
 460		remove_suspend_info(mddev, slot);
 461		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 462		md_wakeup_thread(mddev->thread);
 463		return;
 464	}
 465
 
 
 
 
 
 
 466	/*
 467	 * The bitmaps are not same for different nodes
 468	 * if RESYNCING is happening in one node, then
 469	 * the node which received the RESYNCING message
 470	 * probably will perform resync with the region
 471	 * [lo, hi] again, so we could reduce resync time
 472	 * a lot if we can ensure that the bitmaps among
 473	 * different nodes are match up well.
 474	 *
 475	 * sync_low/hi is used to record the region which
 476	 * arrived in the previous RESYNCING message,
 477	 *
 478	 * Call bitmap_sync_with_cluster to clear
 479	 * NEEDED_MASK and set RESYNC_MASK since
 480	 * resync thread is running in another node,
 481	 * so we don't need to do the resync again
 482	 * with the same section */
 483	bitmap_sync_with_cluster(mddev, cinfo->sync_low,
 484					cinfo->sync_hi,
 485					lo, hi);
 
 
 
 
 486	cinfo->sync_low = lo;
 487	cinfo->sync_hi = hi;
 488
 489	s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
 490	if (!s)
 491		return;
 492	s->slot = slot;
 493	s->lo = lo;
 494	s->hi = hi;
 495	mddev->pers->quiesce(mddev, 1);
 496	spin_lock_irq(&cinfo->suspend_lock);
 497	/* Remove existing entry (if exists) before adding */
 498	__remove_suspend_info(cinfo, slot);
 499	list_add(&s->list, &cinfo->suspend_list);
 500	spin_unlock_irq(&cinfo->suspend_lock);
 501	mddev->pers->quiesce(mddev, 0);
 502}
 503
 504static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
 505{
 506	char disk_uuid[64];
 507	struct md_cluster_info *cinfo = mddev->cluster_info;
 508	char event_name[] = "EVENT=ADD_DEVICE";
 509	char raid_slot[16];
 510	char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
 511	int len;
 512
 513	len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
 514	sprintf(disk_uuid + len, "%pU", cmsg->uuid);
 515	snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
 516	pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
 517	init_completion(&cinfo->newdisk_completion);
 518	set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
 519	kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
 520	wait_for_completion_timeout(&cinfo->newdisk_completion,
 521			NEW_DEV_TIMEOUT);
 522	clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
 523}
 524
 525
 526static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
 527{
 528	int got_lock = 0;
 529	struct md_cluster_info *cinfo = mddev->cluster_info;
 530	mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
 531
 532	dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
 533	wait_event(mddev->thread->wqueue,
 534		   (got_lock = mddev_trylock(mddev)) ||
 535		    test_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state));
 536	md_reload_sb(mddev, mddev->good_device_nr);
 537	if (got_lock)
 538		mddev_unlock(mddev);
 539}
 540
 541static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
 542{
 543	struct md_rdev *rdev;
 544
 545	rcu_read_lock();
 546	rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
 547	if (rdev) {
 548		set_bit(ClusterRemove, &rdev->flags);
 549		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 550		md_wakeup_thread(mddev->thread);
 551	}
 552	else
 553		pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
 554			__func__, __LINE__, le32_to_cpu(msg->raid_slot));
 555	rcu_read_unlock();
 556}
 557
 558static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
 559{
 560	struct md_rdev *rdev;
 561
 562	rcu_read_lock();
 563	rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
 564	if (rdev && test_bit(Faulty, &rdev->flags))
 565		clear_bit(Faulty, &rdev->flags);
 566	else
 567		pr_warn("%s: %d Could not find disk(%d) which is faulty",
 568			__func__, __LINE__, le32_to_cpu(msg->raid_slot));
 569	rcu_read_unlock();
 570}
 571
 572static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
 573{
 574	int ret = 0;
 575
 576	if (WARN(mddev->cluster_info->slot_number - 1 == le32_to_cpu(msg->slot),
 577		"node %d received it's own msg\n", le32_to_cpu(msg->slot)))
 578		return -1;
 579	switch (le32_to_cpu(msg->type)) {
 580	case METADATA_UPDATED:
 581		process_metadata_update(mddev, msg);
 582		break;
 583	case CHANGE_CAPACITY:
 584		set_capacity(mddev->gendisk, mddev->array_sectors);
 585		revalidate_disk(mddev->gendisk);
 586		break;
 587	case RESYNCING:
 
 588		process_suspend_info(mddev, le32_to_cpu(msg->slot),
 589				     le64_to_cpu(msg->low),
 590				     le64_to_cpu(msg->high));
 591		break;
 592	case NEWDISK:
 593		process_add_new_disk(mddev, msg);
 594		break;
 595	case REMOVE:
 596		process_remove_disk(mddev, msg);
 597		break;
 598	case RE_ADD:
 599		process_readd_disk(mddev, msg);
 600		break;
 601	case BITMAP_NEEDS_SYNC:
 602		__recover_slot(mddev, le32_to_cpu(msg->slot));
 603		break;
 
 
 
 
 
 604	default:
 605		ret = -1;
 606		pr_warn("%s:%d Received unknown message from %d\n",
 607			__func__, __LINE__, msg->slot);
 608	}
 609	return ret;
 610}
 611
 612/*
 613 * thread for receiving message
 614 */
 615static void recv_daemon(struct md_thread *thread)
 616{
 617	struct md_cluster_info *cinfo = thread->mddev->cluster_info;
 618	struct dlm_lock_resource *ack_lockres = cinfo->ack_lockres;
 619	struct dlm_lock_resource *message_lockres = cinfo->message_lockres;
 620	struct cluster_msg msg;
 621	int ret;
 622
 623	mutex_lock(&cinfo->recv_mutex);
 624	/*get CR on Message*/
 625	if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) {
 626		pr_err("md/raid1:failed to get CR on MESSAGE\n");
 627		mutex_unlock(&cinfo->recv_mutex);
 628		return;
 629	}
 630
 631	/* read lvb and wake up thread to process this message_lockres */
 632	memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg));
 633	ret = process_recvd_msg(thread->mddev, &msg);
 634	if (ret)
 635		goto out;
 636
 637	/*release CR on ack_lockres*/
 638	ret = dlm_unlock_sync(ack_lockres);
 639	if (unlikely(ret != 0))
 640		pr_info("unlock ack failed return %d\n", ret);
 641	/*up-convert to PR on message_lockres*/
 642	ret = dlm_lock_sync(message_lockres, DLM_LOCK_PR);
 643	if (unlikely(ret != 0))
 644		pr_info("lock PR on msg failed return %d\n", ret);
 645	/*get CR on ack_lockres again*/
 646	ret = dlm_lock_sync(ack_lockres, DLM_LOCK_CR);
 647	if (unlikely(ret != 0))
 648		pr_info("lock CR on ack failed return %d\n", ret);
 649out:
 650	/*release CR on message_lockres*/
 651	ret = dlm_unlock_sync(message_lockres);
 652	if (unlikely(ret != 0))
 653		pr_info("unlock msg failed return %d\n", ret);
 654	mutex_unlock(&cinfo->recv_mutex);
 655}
 656
 657/* lock_token()
 658 * Takes the lock on the TOKEN lock resource so no other
 659 * node can communicate while the operation is underway.
 660 */
 661static int lock_token(struct md_cluster_info *cinfo, bool mddev_locked)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 662{
 663	int error, set_bit = 0;
 664	struct mddev *mddev = cinfo->mddev;
 665
 666	/*
 667	 * If resync thread run after raid1d thread, then process_metadata_update
 668	 * could not continue if raid1d held reconfig_mutex (and raid1d is blocked
 669	 * since another node already got EX on Token and waitting the EX of Ack),
 670	 * so let resync wake up thread in case flag is set.
 671	 */
 672	if (mddev_locked && !test_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
 673				      &cinfo->state)) {
 674		error = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
 675					      &cinfo->state);
 676		WARN_ON_ONCE(error);
 677		md_wakeup_thread(mddev->thread);
 678		set_bit = 1;
 679	}
 680	error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
 681	if (set_bit)
 682		clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
 683
 684	if (error)
 685		pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
 686				__func__, __LINE__, error);
 687
 688	/* Lock the receive sequence */
 689	mutex_lock(&cinfo->recv_mutex);
 690	return error;
 691}
 692
 693/* lock_comm()
 694 * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
 695 */
 696static int lock_comm(struct md_cluster_info *cinfo, bool mddev_locked)
 697{
 698	wait_event(cinfo->wait,
 699		   !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
 700
 701	return lock_token(cinfo, mddev_locked);
 
 
 702}
 703
 704static void unlock_comm(struct md_cluster_info *cinfo)
 705{
 706	WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
 707	mutex_unlock(&cinfo->recv_mutex);
 708	dlm_unlock_sync(cinfo->token_lockres);
 709	clear_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state);
 710	wake_up(&cinfo->wait);
 711}
 712
 713/* __sendmsg()
 714 * This function performs the actual sending of the message. This function is
 715 * usually called after performing the encompassing operation
 716 * The function:
 717 * 1. Grabs the message lockresource in EX mode
 718 * 2. Copies the message to the message LVB
 719 * 3. Downconverts message lockresource to CW
 720 * 4. Upconverts ack lock resource from CR to EX. This forces the BAST on other nodes
 721 *    and the other nodes read the message. The thread will wait here until all other
 722 *    nodes have released ack lock resource.
 723 * 5. Downconvert ack lockresource to CR
 724 */
 725static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
 726{
 727	int error;
 728	int slot = cinfo->slot_number - 1;
 729
 730	cmsg->slot = cpu_to_le32(slot);
 731	/*get EX on Message*/
 732	error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
 733	if (error) {
 734		pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
 735		goto failed_message;
 736	}
 737
 738	memcpy(cinfo->message_lockres->lksb.sb_lvbptr, (void *)cmsg,
 739			sizeof(struct cluster_msg));
 740	/*down-convert EX to CW on Message*/
 741	error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CW);
 742	if (error) {
 743		pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
 744				error);
 745		goto failed_ack;
 746	}
 747
 748	/*up-convert CR to EX on Ack*/
 749	error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
 750	if (error) {
 751		pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
 752				error);
 753		goto failed_ack;
 754	}
 755
 756	/*down-convert EX to CR on Ack*/
 757	error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
 758	if (error) {
 759		pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
 760				error);
 761		goto failed_ack;
 762	}
 763
 764failed_ack:
 765	error = dlm_unlock_sync(cinfo->message_lockres);
 766	if (unlikely(error != 0)) {
 767		pr_err("md-cluster: failed convert to NL on MESSAGE(%d)\n",
 768			error);
 769		/* in case the message can't be released due to some reason */
 770		goto failed_ack;
 771	}
 772failed_message:
 773	return error;
 774}
 775
 776static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg,
 777		   bool mddev_locked)
 778{
 779	int ret;
 780
 781	lock_comm(cinfo, mddev_locked);
 782	ret = __sendmsg(cinfo, cmsg);
 783	unlock_comm(cinfo);
 
 
 784	return ret;
 785}
 786
 787static int gather_all_resync_info(struct mddev *mddev, int total_slots)
 788{
 789	struct md_cluster_info *cinfo = mddev->cluster_info;
 790	int i, ret = 0;
 791	struct dlm_lock_resource *bm_lockres;
 792	struct suspend_info *s;
 793	char str[64];
 794	sector_t lo, hi;
 795
 796
 797	for (i = 0; i < total_slots; i++) {
 798		memset(str, '\0', 64);
 799		snprintf(str, 64, "bitmap%04d", i);
 800		bm_lockres = lockres_init(mddev, str, NULL, 1);
 801		if (!bm_lockres)
 802			return -ENOMEM;
 803		if (i == (cinfo->slot_number - 1)) {
 804			lockres_free(bm_lockres);
 805			continue;
 806		}
 807
 808		bm_lockres->flags |= DLM_LKF_NOQUEUE;
 809		ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
 810		if (ret == -EAGAIN) {
 811			s = read_resync_info(mddev, bm_lockres);
 812			if (s) {
 813				pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
 814						__func__, __LINE__,
 815						(unsigned long long) s->lo,
 816						(unsigned long long) s->hi, i);
 817				spin_lock_irq(&cinfo->suspend_lock);
 818				s->slot = i;
 819				list_add(&s->list, &cinfo->suspend_list);
 820				spin_unlock_irq(&cinfo->suspend_lock);
 821			}
 822			ret = 0;
 823			lockres_free(bm_lockres);
 824			continue;
 825		}
 826		if (ret) {
 827			lockres_free(bm_lockres);
 828			goto out;
 829		}
 830
 831		/* Read the disk bitmap sb and check if it needs recovery */
 832		ret = bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
 833		if (ret) {
 834			pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
 835			lockres_free(bm_lockres);
 836			continue;
 837		}
 838		if ((hi > 0) && (lo < mddev->recovery_cp)) {
 839			set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 840			mddev->recovery_cp = lo;
 841			md_check_recovery(mddev);
 842		}
 843
 844		lockres_free(bm_lockres);
 845	}
 846out:
 847	return ret;
 848}
 849
 850static int join(struct mddev *mddev, int nodes)
 851{
 852	struct md_cluster_info *cinfo;
 853	int ret, ops_rv;
 854	char str[64];
 855
 856	cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
 857	if (!cinfo)
 858		return -ENOMEM;
 859
 860	INIT_LIST_HEAD(&cinfo->suspend_list);
 861	spin_lock_init(&cinfo->suspend_lock);
 862	init_completion(&cinfo->completion);
 863	set_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
 864	init_waitqueue_head(&cinfo->wait);
 865	mutex_init(&cinfo->recv_mutex);
 866
 867	mddev->cluster_info = cinfo;
 868	cinfo->mddev = mddev;
 869
 870	memset(str, 0, 64);
 871	sprintf(str, "%pU", mddev->uuid);
 872	ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
 873				DLM_LSFL_FS, LVB_SIZE,
 874				&md_ls_ops, mddev, &ops_rv, &cinfo->lockspace);
 875	if (ret)
 876		goto err;
 877	wait_for_completion(&cinfo->completion);
 878	if (nodes < cinfo->slot_number) {
 879		pr_err("md-cluster: Slot allotted(%d) is greater than available slots(%d).",
 880			cinfo->slot_number, nodes);
 881		ret = -ERANGE;
 882		goto err;
 883	}
 884	/* Initiate the communication resources */
 885	ret = -ENOMEM;
 886	cinfo->recv_thread = md_register_thread(recv_daemon, mddev, "cluster_recv");
 887	if (!cinfo->recv_thread) {
 888		pr_err("md-cluster: cannot allocate memory for recv_thread!\n");
 889		goto err;
 890	}
 891	cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
 892	if (!cinfo->message_lockres)
 893		goto err;
 894	cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
 895	if (!cinfo->token_lockres)
 896		goto err;
 897	cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
 898	if (!cinfo->no_new_dev_lockres)
 899		goto err;
 900
 901	ret = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
 902	if (ret) {
 903		ret = -EAGAIN;
 904		pr_err("md-cluster: can't join cluster to avoid lock issue\n");
 905		goto err;
 906	}
 907	cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
 908	if (!cinfo->ack_lockres) {
 909		ret = -ENOMEM;
 910		goto err;
 911	}
 912	/* get sync CR lock on ACK. */
 913	if (dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR))
 914		pr_err("md-cluster: failed to get a sync CR lock on ACK!(%d)\n",
 915				ret);
 916	dlm_unlock_sync(cinfo->token_lockres);
 917	/* get sync CR lock on no-new-dev. */
 918	if (dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR))
 919		pr_err("md-cluster: failed to get a sync CR lock on no-new-dev!(%d)\n", ret);
 920
 921
 922	pr_info("md-cluster: Joined cluster %s slot %d\n", str, cinfo->slot_number);
 923	snprintf(str, 64, "bitmap%04d", cinfo->slot_number - 1);
 924	cinfo->bitmap_lockres = lockres_init(mddev, str, NULL, 1);
 925	if (!cinfo->bitmap_lockres) {
 926		ret = -ENOMEM;
 927		goto err;
 928	}
 929	if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
 930		pr_err("Failed to get bitmap lock\n");
 931		ret = -EINVAL;
 932		goto err;
 933	}
 934
 935	cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
 936	if (!cinfo->resync_lockres) {
 937		ret = -ENOMEM;
 938		goto err;
 939	}
 940
 941	return 0;
 942err:
 943	set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
 944	md_unregister_thread(&cinfo->recovery_thread);
 945	md_unregister_thread(&cinfo->recv_thread);
 946	lockres_free(cinfo->message_lockres);
 947	lockres_free(cinfo->token_lockres);
 948	lockres_free(cinfo->ack_lockres);
 949	lockres_free(cinfo->no_new_dev_lockres);
 950	lockres_free(cinfo->resync_lockres);
 951	lockres_free(cinfo->bitmap_lockres);
 952	if (cinfo->lockspace)
 953		dlm_release_lockspace(cinfo->lockspace, 2);
 954	mddev->cluster_info = NULL;
 955	kfree(cinfo);
 956	return ret;
 957}
 958
 959static void load_bitmaps(struct mddev *mddev, int total_slots)
 960{
 961	struct md_cluster_info *cinfo = mddev->cluster_info;
 962
 963	/* load all the node's bitmap info for resync */
 964	if (gather_all_resync_info(mddev, total_slots))
 965		pr_err("md-cluster: failed to gather all resyn infos\n");
 966	set_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state);
 967	/* wake up recv thread in case something need to be handled */
 968	if (test_and_clear_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state))
 969		md_wakeup_thread(cinfo->recv_thread);
 970}
 971
 972static void resync_bitmap(struct mddev *mddev)
 973{
 974	struct md_cluster_info *cinfo = mddev->cluster_info;
 975	struct cluster_msg cmsg = {0};
 976	int err;
 977
 978	cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
 979	err = sendmsg(cinfo, &cmsg, 1);
 980	if (err)
 981		pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
 982			__func__, __LINE__, err);
 983}
 984
 985static void unlock_all_bitmaps(struct mddev *mddev);
 986static int leave(struct mddev *mddev)
 987{
 988	struct md_cluster_info *cinfo = mddev->cluster_info;
 989
 990	if (!cinfo)
 991		return 0;
 992
 993	/* BITMAP_NEEDS_SYNC message should be sent when node
 
 994	 * is leaving the cluster with dirty bitmap, also we
 995	 * can only deliver it when dlm connection is available */
 996	if (cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector)
 
 
 
 
 
 
 997		resync_bitmap(mddev);
 998
 999	set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
1000	md_unregister_thread(&cinfo->recovery_thread);
1001	md_unregister_thread(&cinfo->recv_thread);
1002	lockres_free(cinfo->message_lockres);
1003	lockres_free(cinfo->token_lockres);
1004	lockres_free(cinfo->ack_lockres);
1005	lockres_free(cinfo->no_new_dev_lockres);
1006	lockres_free(cinfo->resync_lockres);
1007	lockres_free(cinfo->bitmap_lockres);
1008	unlock_all_bitmaps(mddev);
1009	dlm_release_lockspace(cinfo->lockspace, 2);
1010	kfree(cinfo);
1011	return 0;
1012}
1013
1014/* slot_number(): Returns the MD slot number to use
1015 * DLM starts the slot numbers from 1, wheras cluster-md
1016 * wants the number to be from zero, so we deduct one
1017 */
1018static int slot_number(struct mddev *mddev)
1019{
1020	struct md_cluster_info *cinfo = mddev->cluster_info;
1021
1022	return cinfo->slot_number - 1;
1023}
1024
1025/*
1026 * Check if the communication is already locked, else lock the communication
1027 * channel.
1028 * If it is already locked, token is in EX mode, and hence lock_token()
1029 * should not be called.
1030 */
1031static int metadata_update_start(struct mddev *mddev)
1032{
1033	struct md_cluster_info *cinfo = mddev->cluster_info;
1034	int ret;
1035
1036	/*
1037	 * metadata_update_start is always called with the protection of
1038	 * reconfig_mutex, so set WAITING_FOR_TOKEN here.
1039	 */
1040	ret = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
1041				    &cinfo->state);
1042	WARN_ON_ONCE(ret);
1043	md_wakeup_thread(mddev->thread);
1044
1045	wait_event(cinfo->wait,
1046		   !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state) ||
1047		   test_and_clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state));
1048
1049	/* If token is already locked, return 0 */
1050	if (cinfo->token_lockres->mode == DLM_LOCK_EX) {
1051		clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
1052		return 0;
1053	}
1054
1055	ret = lock_token(cinfo, 1);
1056	clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
1057	return ret;
1058}
1059
1060static int metadata_update_finish(struct mddev *mddev)
1061{
1062	struct md_cluster_info *cinfo = mddev->cluster_info;
1063	struct cluster_msg cmsg;
1064	struct md_rdev *rdev;
1065	int ret = 0;
1066	int raid_slot = -1;
1067
1068	memset(&cmsg, 0, sizeof(cmsg));
1069	cmsg.type = cpu_to_le32(METADATA_UPDATED);
1070	/* Pick up a good active device number to send.
1071	 */
1072	rdev_for_each(rdev, mddev)
1073		if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
1074			raid_slot = rdev->desc_nr;
1075			break;
1076		}
1077	if (raid_slot >= 0) {
1078		cmsg.raid_slot = cpu_to_le32(raid_slot);
1079		ret = __sendmsg(cinfo, &cmsg);
1080	} else
1081		pr_warn("md-cluster: No good device id found to send\n");
1082	clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1083	unlock_comm(cinfo);
1084	return ret;
1085}
1086
1087static void metadata_update_cancel(struct mddev *mddev)
1088{
1089	struct md_cluster_info *cinfo = mddev->cluster_info;
1090	clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1091	unlock_comm(cinfo);
1092}
1093
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1094/*
1095 * return 0 if all the bitmaps have the same sync_size
1096 */
1097static int cluster_check_sync_size(struct mddev *mddev)
1098{
1099	int i, rv;
1100	bitmap_super_t *sb;
1101	unsigned long my_sync_size, sync_size = 0;
1102	int node_num = mddev->bitmap_info.nodes;
1103	int current_slot = md_cluster_ops->slot_number(mddev);
1104	struct bitmap *bitmap = mddev->bitmap;
1105	char str[64];
1106	struct dlm_lock_resource *bm_lockres;
1107
1108	sb = kmap_atomic(bitmap->storage.sb_page);
1109	my_sync_size = sb->sync_size;
1110	kunmap_atomic(sb);
1111
1112	for (i = 0; i < node_num; i++) {
1113		if (i == current_slot)
1114			continue;
1115
1116		bitmap = get_bitmap_from_slot(mddev, i);
1117		if (IS_ERR(bitmap)) {
1118			pr_err("can't get bitmap from slot %d\n", i);
1119			return -1;
1120		}
1121
1122		/*
1123		 * If we can hold the bitmap lock of one node then
1124		 * the slot is not occupied, update the sb.
1125		 */
1126		snprintf(str, 64, "bitmap%04d", i);
1127		bm_lockres = lockres_init(mddev, str, NULL, 1);
1128		if (!bm_lockres) {
1129			pr_err("md-cluster: Cannot initialize %s\n", str);
1130			bitmap_free(bitmap);
1131			return -1;
1132		}
1133		bm_lockres->flags |= DLM_LKF_NOQUEUE;
1134		rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
1135		if (!rv)
1136			bitmap_update_sb(bitmap);
1137		lockres_free(bm_lockres);
1138
1139		sb = kmap_atomic(bitmap->storage.sb_page);
1140		if (sync_size == 0)
1141			sync_size = sb->sync_size;
1142		else if (sync_size != sb->sync_size) {
1143			kunmap_atomic(sb);
1144			bitmap_free(bitmap);
1145			return -1;
1146		}
1147		kunmap_atomic(sb);
1148		bitmap_free(bitmap);
1149	}
1150
1151	return (my_sync_size == sync_size) ? 0 : -1;
1152}
1153
1154/*
1155 * Update the size for cluster raid is a little more complex, we perform it
1156 * by the steps:
1157 * 1. hold token lock and update superblock in initiator node.
1158 * 2. send METADATA_UPDATED msg to other nodes.
1159 * 3. The initiator node continues to check each bitmap's sync_size, if all
1160 *    bitmaps have the same value of sync_size, then we can set capacity and
1161 *    let other nodes to perform it. If one node can't update sync_size
1162 *    accordingly, we need to revert to previous value.
1163 */
1164static void update_size(struct mddev *mddev, sector_t old_dev_sectors)
1165{
1166	struct md_cluster_info *cinfo = mddev->cluster_info;
1167	struct cluster_msg cmsg;
1168	struct md_rdev *rdev;
1169	int ret = 0;
1170	int raid_slot = -1;
1171
1172	md_update_sb(mddev, 1);
1173	lock_comm(cinfo, 1);
 
 
 
1174
1175	memset(&cmsg, 0, sizeof(cmsg));
1176	cmsg.type = cpu_to_le32(METADATA_UPDATED);
1177	rdev_for_each(rdev, mddev)
1178		if (rdev->raid_disk >= 0 && !test_bit(Faulty, &rdev->flags)) {
1179			raid_slot = rdev->desc_nr;
1180			break;
1181		}
1182	if (raid_slot >= 0) {
1183		cmsg.raid_slot = cpu_to_le32(raid_slot);
1184		/*
1185		 * We can only change capiticy after all the nodes can do it,
1186		 * so need to wait after other nodes already received the msg
1187		 * and handled the change
1188		 */
1189		ret = __sendmsg(cinfo, &cmsg);
1190		if (ret) {
1191			pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",
1192			       __func__, __LINE__);
1193			unlock_comm(cinfo);
1194			return;
1195		}
1196	} else {
1197		pr_err("md-cluster: No good device id found to send\n");
1198		unlock_comm(cinfo);
1199		return;
1200	}
1201
1202	/*
1203	 * check the sync_size from other node's bitmap, if sync_size
1204	 * have already updated in other nodes as expected, send an
1205	 * empty metadata msg to permit the change of capacity
1206	 */
1207	if (cluster_check_sync_size(mddev) == 0) {
1208		memset(&cmsg, 0, sizeof(cmsg));
1209		cmsg.type = cpu_to_le32(CHANGE_CAPACITY);
1210		ret = __sendmsg(cinfo, &cmsg);
1211		if (ret)
1212			pr_err("%s:%d: failed to send CHANGE_CAPACITY msg\n",
1213			       __func__, __LINE__);
1214		set_capacity(mddev->gendisk, mddev->array_sectors);
1215		revalidate_disk(mddev->gendisk);
1216	} else {
1217		/* revert to previous sectors */
1218		ret = mddev->pers->resize(mddev, old_dev_sectors);
1219		if (!ret)
1220			revalidate_disk(mddev->gendisk);
1221		ret = __sendmsg(cinfo, &cmsg);
1222		if (ret)
1223			pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",
1224			       __func__, __LINE__);
1225	}
1226	unlock_comm(cinfo);
1227}
1228
1229static int resync_start(struct mddev *mddev)
1230{
1231	struct md_cluster_info *cinfo = mddev->cluster_info;
1232	return dlm_lock_sync_interruptible(cinfo->resync_lockres, DLM_LOCK_EX, mddev);
1233}
1234
 
 
 
 
 
 
 
 
 
 
1235static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
1236{
1237	struct md_cluster_info *cinfo = mddev->cluster_info;
1238	struct resync_info ri;
1239	struct cluster_msg cmsg = {0};
1240
1241	/* do not send zero again, if we have sent before */
1242	if (hi == 0) {
1243		memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
1244		if (le64_to_cpu(ri.hi) == 0)
1245			return 0;
1246	}
1247
1248	add_resync_info(cinfo->bitmap_lockres, lo, hi);
1249	/* Re-acquire the lock to refresh LVB */
1250	dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
1251	cmsg.type = cpu_to_le32(RESYNCING);
1252	cmsg.low = cpu_to_le64(lo);
1253	cmsg.high = cpu_to_le64(hi);
1254
1255	/*
1256	 * mddev_lock is held if resync_info_update is called from
1257	 * resync_finish (md_reap_sync_thread -> resync_finish)
1258	 */
1259	if (lo == 0 && hi == 0)
1260		return sendmsg(cinfo, &cmsg, 1);
1261	else
1262		return sendmsg(cinfo, &cmsg, 0);
1263}
1264
1265static int resync_finish(struct mddev *mddev)
1266{
1267	struct md_cluster_info *cinfo = mddev->cluster_info;
 
 
 
 
 
 
 
 
 
 
1268	dlm_unlock_sync(cinfo->resync_lockres);
1269	return resync_info_update(mddev, 0, 0);
1270}
1271
1272static int area_resyncing(struct mddev *mddev, int direction,
1273		sector_t lo, sector_t hi)
1274{
1275	struct md_cluster_info *cinfo = mddev->cluster_info;
1276	int ret = 0;
1277	struct suspend_info *s;
1278
1279	if ((direction == READ) &&
1280		test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
1281		return 1;
1282
1283	spin_lock_irq(&cinfo->suspend_lock);
1284	if (list_empty(&cinfo->suspend_list))
1285		goto out;
1286	list_for_each_entry(s, &cinfo->suspend_list, list)
1287		if (hi > s->lo && lo < s->hi) {
1288			ret = 1;
1289			break;
1290		}
1291out:
1292	spin_unlock_irq(&cinfo->suspend_lock);
1293	return ret;
1294}
1295
1296/* add_new_disk() - initiates a disk add
1297 * However, if this fails before writing md_update_sb(),
1298 * add_new_disk_cancel() must be called to release token lock
1299 */
1300static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
1301{
1302	struct md_cluster_info *cinfo = mddev->cluster_info;
1303	struct cluster_msg cmsg;
1304	int ret = 0;
1305	struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1306	char *uuid = sb->device_uuid;
1307
1308	memset(&cmsg, 0, sizeof(cmsg));
1309	cmsg.type = cpu_to_le32(NEWDISK);
1310	memcpy(cmsg.uuid, uuid, 16);
1311	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1312	lock_comm(cinfo, 1);
 
1313	ret = __sendmsg(cinfo, &cmsg);
1314	if (ret) {
1315		unlock_comm(cinfo);
1316		return ret;
1317	}
1318	cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
1319	ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
1320	cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;
1321	/* Some node does not "see" the device */
1322	if (ret == -EAGAIN)
1323		ret = -ENOENT;
1324	if (ret)
1325		unlock_comm(cinfo);
1326	else {
1327		dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
1328		/* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
1329		 * will run soon after add_new_disk, the below path will be
1330		 * invoked:
1331		 *   md_wakeup_thread(mddev->thread)
1332		 *	-> conf->thread (raid1d)
1333		 *	-> md_check_recovery -> md_update_sb
1334		 *	-> metadata_update_start/finish
1335		 * MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
1336		 *
1337		 * For other failure cases, metadata_update_cancel and
1338		 * add_new_disk_cancel also clear below bit as well.
1339		 * */
1340		set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1341		wake_up(&cinfo->wait);
1342	}
1343	return ret;
1344}
1345
1346static void add_new_disk_cancel(struct mddev *mddev)
1347{
1348	struct md_cluster_info *cinfo = mddev->cluster_info;
1349	clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
1350	unlock_comm(cinfo);
1351}
1352
1353static int new_disk_ack(struct mddev *mddev, bool ack)
1354{
1355	struct md_cluster_info *cinfo = mddev->cluster_info;
1356
1357	if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
1358		pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
1359		return -EINVAL;
1360	}
1361
1362	if (ack)
1363		dlm_unlock_sync(cinfo->no_new_dev_lockres);
1364	complete(&cinfo->newdisk_completion);
1365	return 0;
1366}
1367
1368static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1369{
1370	struct cluster_msg cmsg = {0};
1371	struct md_cluster_info *cinfo = mddev->cluster_info;
1372	cmsg.type = cpu_to_le32(REMOVE);
1373	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1374	return sendmsg(cinfo, &cmsg, 1);
1375}
1376
1377static int lock_all_bitmaps(struct mddev *mddev)
1378{
1379	int slot, my_slot, ret, held = 1, i = 0;
1380	char str[64];
1381	struct md_cluster_info *cinfo = mddev->cluster_info;
1382
1383	cinfo->other_bitmap_lockres = kzalloc((mddev->bitmap_info.nodes - 1) *
1384					     sizeof(struct dlm_lock_resource *),
1385					     GFP_KERNEL);
1386	if (!cinfo->other_bitmap_lockres) {
1387		pr_err("md: can't alloc mem for other bitmap locks\n");
1388		return 0;
1389	}
1390
1391	my_slot = slot_number(mddev);
1392	for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
1393		if (slot == my_slot)
1394			continue;
1395
1396		memset(str, '\0', 64);
1397		snprintf(str, 64, "bitmap%04d", slot);
1398		cinfo->other_bitmap_lockres[i] = lockres_init(mddev, str, NULL, 1);
1399		if (!cinfo->other_bitmap_lockres[i])
1400			return -ENOMEM;
1401
1402		cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
1403		ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
1404		if (ret)
1405			held = -1;
1406		i++;
1407	}
1408
1409	return held;
1410}
1411
1412static void unlock_all_bitmaps(struct mddev *mddev)
1413{
1414	struct md_cluster_info *cinfo = mddev->cluster_info;
1415	int i;
1416
1417	/* release other node's bitmap lock if they are existed */
1418	if (cinfo->other_bitmap_lockres) {
1419		for (i = 0; i < mddev->bitmap_info.nodes - 1; i++) {
1420			if (cinfo->other_bitmap_lockres[i]) {
1421				lockres_free(cinfo->other_bitmap_lockres[i]);
1422			}
1423		}
1424		kfree(cinfo->other_bitmap_lockres);
 
1425	}
1426}
1427
1428static int gather_bitmaps(struct md_rdev *rdev)
1429{
1430	int sn, err;
1431	sector_t lo, hi;
1432	struct cluster_msg cmsg = {0};
1433	struct mddev *mddev = rdev->mddev;
1434	struct md_cluster_info *cinfo = mddev->cluster_info;
1435
1436	cmsg.type = cpu_to_le32(RE_ADD);
1437	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
1438	err = sendmsg(cinfo, &cmsg, 1);
1439	if (err)
1440		goto out;
1441
1442	for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
1443		if (sn == (cinfo->slot_number - 1))
1444			continue;
1445		err = bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
1446		if (err) {
1447			pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
1448			goto out;
1449		}
1450		if ((hi > 0) && (lo < mddev->recovery_cp))
1451			mddev->recovery_cp = lo;
1452	}
1453out:
1454	return err;
1455}
1456
1457static struct md_cluster_operations cluster_ops = {
1458	.join   = join,
1459	.leave  = leave,
1460	.slot_number = slot_number,
1461	.resync_start = resync_start,
1462	.resync_finish = resync_finish,
1463	.resync_info_update = resync_info_update,
 
1464	.metadata_update_start = metadata_update_start,
1465	.metadata_update_finish = metadata_update_finish,
1466	.metadata_update_cancel = metadata_update_cancel,
1467	.area_resyncing = area_resyncing,
1468	.add_new_disk = add_new_disk,
1469	.add_new_disk_cancel = add_new_disk_cancel,
1470	.new_disk_ack = new_disk_ack,
1471	.remove_disk = remove_disk,
1472	.load_bitmaps = load_bitmaps,
1473	.gather_bitmaps = gather_bitmaps,
 
1474	.lock_all_bitmaps = lock_all_bitmaps,
1475	.unlock_all_bitmaps = unlock_all_bitmaps,
1476	.update_size = update_size,
1477};
1478
1479static int __init cluster_init(void)
1480{
1481	pr_warn("md-cluster: support raid1 and raid10 (limited support)\n");
1482	pr_info("Registering Cluster MD functions\n");
1483	register_md_cluster_operations(&cluster_ops, THIS_MODULE);
1484	return 0;
1485}
1486
1487static void cluster_exit(void)
1488{
1489	unregister_md_cluster_operations();
1490}
1491
1492module_init(cluster_init);
1493module_exit(cluster_exit);
1494MODULE_AUTHOR("SUSE");
1495MODULE_LICENSE("GPL");
1496MODULE_DESCRIPTION("Clustering support for MD");