v4.19.13 snapshot.
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
new file mode 100644
index 0000000..0b2af6e
--- /dev/null
+++ b/drivers/md/md-cluster.c
@@ -0,0 +1,1517 @@
+/*
+ * Copyright (C) 2015, SUSE
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ */
+
+
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/dlm.h>
+#include <linux/sched.h>
+#include <linux/raid/md_p.h>
+#include "md.h"
+#include "md-bitmap.h"
+#include "md-cluster.h"
+
+#define LVB_SIZE 64
+#define NEW_DEV_TIMEOUT 5000
+
+struct dlm_lock_resource {
+ dlm_lockspace_t *ls;
+ struct dlm_lksb lksb;
+ char *name; /* lock name. */
+ uint32_t flags; /* flags to pass to dlm_lock() */
+ wait_queue_head_t sync_locking; /* wait queue for synchronized locking */
+ bool sync_locking_done;
+ void (*bast)(void *arg, int mode); /* blocking AST function pointer*/
+ struct mddev *mddev; /* pointing back to mddev. */
+ int mode;
+};
+
+struct suspend_info {
+ int slot;
+ sector_t lo;
+ sector_t hi;
+ struct list_head list;
+};
+
+struct resync_info {
+ __le64 lo;
+ __le64 hi;
+};
+
+/* md_cluster_info flags */
+#define MD_CLUSTER_WAITING_FOR_NEWDISK 1
+#define MD_CLUSTER_SUSPEND_READ_BALANCING 2
+#define MD_CLUSTER_BEGIN_JOIN_CLUSTER 3
+
+/* Lock the send communication. This is done through
+ * bit manipulation as opposed to a mutex in order to
+ * accomodate lock and hold. See next comment.
+ */
+#define MD_CLUSTER_SEND_LOCK 4
+/* If cluster operations (such as adding a disk) must lock the
+ * communication channel, so as to perform extra operations
+ * (update metadata) and no other operation is allowed on the
+ * MD. Token needs to be locked and held until the operation
+ * completes witha md_update_sb(), which would eventually release
+ * the lock.
+ */
+#define MD_CLUSTER_SEND_LOCKED_ALREADY 5
+/* We should receive message after node joined cluster and
+ * set up all the related infos such as bitmap and personality */
+#define MD_CLUSTER_ALREADY_IN_CLUSTER 6
+#define MD_CLUSTER_PENDING_RECV_EVENT 7
+#define MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD 8
+
+struct md_cluster_info {
+ struct mddev *mddev; /* the md device which md_cluster_info belongs to */
+ /* dlm lock space and resources for clustered raid. */
+ dlm_lockspace_t *lockspace;
+ int slot_number;
+ struct completion completion;
+ struct mutex recv_mutex;
+ struct dlm_lock_resource *bitmap_lockres;
+ struct dlm_lock_resource **other_bitmap_lockres;
+ struct dlm_lock_resource *resync_lockres;
+ struct list_head suspend_list;
+ spinlock_t suspend_lock;
+ struct md_thread *recovery_thread;
+ unsigned long recovery_map;
+ /* communication loc resources */
+ struct dlm_lock_resource *ack_lockres;
+ struct dlm_lock_resource *message_lockres;
+ struct dlm_lock_resource *token_lockres;
+ struct dlm_lock_resource *no_new_dev_lockres;
+ struct md_thread *recv_thread;
+ struct completion newdisk_completion;
+ wait_queue_head_t wait;
+ unsigned long state;
+ /* record the region in RESYNCING message */
+ sector_t sync_low;
+ sector_t sync_hi;
+};
+
+enum msg_type {
+ METADATA_UPDATED = 0,
+ RESYNCING,
+ NEWDISK,
+ REMOVE,
+ RE_ADD,
+ BITMAP_NEEDS_SYNC,
+ CHANGE_CAPACITY,
+};
+
+struct cluster_msg {
+ __le32 type;
+ __le32 slot;
+ /* TODO: Unionize this for smaller footprint */
+ __le64 low;
+ __le64 high;
+ char uuid[16];
+ __le32 raid_slot;
+};
+
+static void sync_ast(void *arg)
+{
+ struct dlm_lock_resource *res;
+
+ res = arg;
+ res->sync_locking_done = true;
+ wake_up(&res->sync_locking);
+}
+
+static int dlm_lock_sync(struct dlm_lock_resource *res, int mode)
+{
+ int ret = 0;
+
+ ret = dlm_lock(res->ls, mode, &res->lksb,
+ res->flags, res->name, strlen(res->name),
+ 0, sync_ast, res, res->bast);
+ if (ret)
+ return ret;
+ wait_event(res->sync_locking, res->sync_locking_done);
+ res->sync_locking_done = false;
+ if (res->lksb.sb_status == 0)
+ res->mode = mode;
+ return res->lksb.sb_status;
+}
+
+static int dlm_unlock_sync(struct dlm_lock_resource *res)
+{
+ return dlm_lock_sync(res, DLM_LOCK_NL);
+}
+
+/*
+ * An variation of dlm_lock_sync, which make lock request could
+ * be interrupted
+ */
+static int dlm_lock_sync_interruptible(struct dlm_lock_resource *res, int mode,
+ struct mddev *mddev)
+{
+ int ret = 0;
+
+ ret = dlm_lock(res->ls, mode, &res->lksb,
+ res->flags, res->name, strlen(res->name),
+ 0, sync_ast, res, res->bast);
+ if (ret)
+ return ret;
+
+ wait_event(res->sync_locking, res->sync_locking_done
+ || kthread_should_stop()
+ || test_bit(MD_CLOSING, &mddev->flags));
+ if (!res->sync_locking_done) {
+ /*
+ * the convert queue contains the lock request when request is
+ * interrupted, and sync_ast could still be run, so need to
+ * cancel the request and reset completion
+ */
+ ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_CANCEL,
+ &res->lksb, res);
+ res->sync_locking_done = false;
+ if (unlikely(ret != 0))
+ pr_info("failed to cancel previous lock request "
+ "%s return %d\n", res->name, ret);
+ return -EPERM;
+ } else
+ res->sync_locking_done = false;
+ if (res->lksb.sb_status == 0)
+ res->mode = mode;
+ return res->lksb.sb_status;
+}
+
+static struct dlm_lock_resource *lockres_init(struct mddev *mddev,
+ char *name, void (*bastfn)(void *arg, int mode), int with_lvb)
+{
+ struct dlm_lock_resource *res = NULL;
+ int ret, namelen;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ res = kzalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
+ if (!res)
+ return NULL;
+ init_waitqueue_head(&res->sync_locking);
+ res->sync_locking_done = false;
+ res->ls = cinfo->lockspace;
+ res->mddev = mddev;
+ res->mode = DLM_LOCK_IV;
+ namelen = strlen(name);
+ res->name = kzalloc(namelen + 1, GFP_KERNEL);
+ if (!res->name) {
+ pr_err("md-cluster: Unable to allocate resource name for resource %s\n", name);
+ goto out_err;
+ }
+ strlcpy(res->name, name, namelen + 1);
+ if (with_lvb) {
+ res->lksb.sb_lvbptr = kzalloc(LVB_SIZE, GFP_KERNEL);
+ if (!res->lksb.sb_lvbptr) {
+ pr_err("md-cluster: Unable to allocate LVB for resource %s\n", name);
+ goto out_err;
+ }
+ res->flags = DLM_LKF_VALBLK;
+ }
+
+ if (bastfn)
+ res->bast = bastfn;
+
+ res->flags |= DLM_LKF_EXPEDITE;
+
+ ret = dlm_lock_sync(res, DLM_LOCK_NL);
+ if (ret) {
+ pr_err("md-cluster: Unable to lock NL on new lock resource %s\n", name);
+ goto out_err;
+ }
+ res->flags &= ~DLM_LKF_EXPEDITE;
+ res->flags |= DLM_LKF_CONVERT;
+
+ return res;
+out_err:
+ kfree(res->lksb.sb_lvbptr);
+ kfree(res->name);
+ kfree(res);
+ return NULL;
+}
+
+static void lockres_free(struct dlm_lock_resource *res)
+{
+ int ret = 0;
+
+ if (!res)
+ return;
+
+ /*
+ * use FORCEUNLOCK flag, so we can unlock even the lock is on the
+ * waiting or convert queue
+ */
+ ret = dlm_unlock(res->ls, res->lksb.sb_lkid, DLM_LKF_FORCEUNLOCK,
+ &res->lksb, res);
+ if (unlikely(ret != 0))
+ pr_err("failed to unlock %s return %d\n", res->name, ret);
+ else
+ wait_event(res->sync_locking, res->sync_locking_done);
+
+ kfree(res->name);
+ kfree(res->lksb.sb_lvbptr);
+ kfree(res);
+}
+
+static void add_resync_info(struct dlm_lock_resource *lockres,
+ sector_t lo, sector_t hi)
+{
+ struct resync_info *ri;
+
+ ri = (struct resync_info *)lockres->lksb.sb_lvbptr;
+ ri->lo = cpu_to_le64(lo);
+ ri->hi = cpu_to_le64(hi);
+}
+
+static struct suspend_info *read_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres)
+{
+ struct resync_info ri;
+ struct suspend_info *s = NULL;
+ sector_t hi = 0;
+
+ dlm_lock_sync(lockres, DLM_LOCK_CR);
+ memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
+ hi = le64_to_cpu(ri.hi);
+ if (hi > 0) {
+ s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
+ if (!s)
+ goto out;
+ s->hi = hi;
+ s->lo = le64_to_cpu(ri.lo);
+ }
+ dlm_unlock_sync(lockres);
+out:
+ return s;
+}
+
+static void recover_bitmaps(struct md_thread *thread)
+{
+ struct mddev *mddev = thread->mddev;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct dlm_lock_resource *bm_lockres;
+ char str[64];
+ int slot, ret;
+ struct suspend_info *s, *tmp;
+ sector_t lo, hi;
+
+ while (cinfo->recovery_map) {
+ slot = fls64((u64)cinfo->recovery_map) - 1;
+
+ snprintf(str, 64, "bitmap%04d", slot);
+ bm_lockres = lockres_init(mddev, str, NULL, 1);
+ if (!bm_lockres) {
+ pr_err("md-cluster: Cannot initialize bitmaps\n");
+ goto clear_bit;
+ }
+
+ ret = dlm_lock_sync_interruptible(bm_lockres, DLM_LOCK_PW, mddev);
+ if (ret) {
+ pr_err("md-cluster: Could not DLM lock %s: %d\n",
+ str, ret);
+ goto clear_bit;
+ }
+ ret = md_bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
+ if (ret) {
+ pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
+ goto clear_bit;
+ }
+
+ /* Clear suspend_area associated with the bitmap */
+ spin_lock_irq(&cinfo->suspend_lock);
+ list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
+ if (slot == s->slot) {
+ list_del(&s->list);
+ kfree(s);
+ }
+ spin_unlock_irq(&cinfo->suspend_lock);
+
+ if (hi > 0) {
+ if (lo < mddev->recovery_cp)
+ mddev->recovery_cp = lo;
+ /* wake up thread to continue resync in case resync
+ * is not finished */
+ if (mddev->recovery_cp != MaxSector) {
+ /*
+ * clear the REMOTE flag since we will launch
+ * resync thread in current node.
+ */
+ clear_bit(MD_RESYNCING_REMOTE,
+ &mddev->recovery);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+ md_wakeup_thread(mddev->thread);
+ }
+ }
+clear_bit:
+ lockres_free(bm_lockres);
+ clear_bit(slot, &cinfo->recovery_map);
+ }
+}
+
+static void recover_prep(void *arg)
+{
+ struct mddev *mddev = arg;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ set_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
+}
+
+static void __recover_slot(struct mddev *mddev, int slot)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ set_bit(slot, &cinfo->recovery_map);
+ if (!cinfo->recovery_thread) {
+ cinfo->recovery_thread = md_register_thread(recover_bitmaps,
+ mddev, "recover");
+ if (!cinfo->recovery_thread) {
+ pr_warn("md-cluster: Could not create recovery thread\n");
+ return;
+ }
+ }
+ md_wakeup_thread(cinfo->recovery_thread);
+}
+
+static void recover_slot(void *arg, struct dlm_slot *slot)
+{
+ struct mddev *mddev = arg;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
+ mddev->bitmap_info.cluster_name,
+ slot->nodeid, slot->slot,
+ cinfo->slot_number);
+ /* deduct one since dlm slot starts from one while the num of
+ * cluster-md begins with 0 */
+ __recover_slot(mddev, slot->slot - 1);
+}
+
+static void recover_done(void *arg, struct dlm_slot *slots,
+ int num_slots, int our_slot,
+ uint32_t generation)
+{
+ struct mddev *mddev = arg;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ cinfo->slot_number = our_slot;
+ /* completion is only need to be complete when node join cluster,
+ * it doesn't need to run during another node's failure */
+ if (test_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state)) {
+ complete(&cinfo->completion);
+ clear_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
+ }
+ clear_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state);
+}
+
+/* the ops is called when node join the cluster, and do lock recovery
+ * if node failure occurs */
+static const struct dlm_lockspace_ops md_ls_ops = {
+ .recover_prep = recover_prep,
+ .recover_slot = recover_slot,
+ .recover_done = recover_done,
+};
+
+/*
+ * The BAST function for the ack lock resource
+ * This function wakes up the receive thread in
+ * order to receive and process the message.
+ */
+static void ack_bast(void *arg, int mode)
+{
+ struct dlm_lock_resource *res = arg;
+ struct md_cluster_info *cinfo = res->mddev->cluster_info;
+
+ if (mode == DLM_LOCK_EX) {
+ if (test_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state))
+ md_wakeup_thread(cinfo->recv_thread);
+ else
+ set_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state);
+ }
+}
+
+static void __remove_suspend_info(struct md_cluster_info *cinfo, int slot)
+{
+ struct suspend_info *s, *tmp;
+
+ list_for_each_entry_safe(s, tmp, &cinfo->suspend_list, list)
+ if (slot == s->slot) {
+ list_del(&s->list);
+ kfree(s);
+ break;
+ }
+}
+
+static void remove_suspend_info(struct mddev *mddev, int slot)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ mddev->pers->quiesce(mddev, 1);
+ spin_lock_irq(&cinfo->suspend_lock);
+ __remove_suspend_info(cinfo, slot);
+ spin_unlock_irq(&cinfo->suspend_lock);
+ mddev->pers->quiesce(mddev, 0);
+}
+
+
+static void process_suspend_info(struct mddev *mddev,
+ int slot, sector_t lo, sector_t hi)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct suspend_info *s;
+
+ if (!hi) {
+ /*
+ * clear the REMOTE flag since resync or recovery is finished
+ * in remote node.
+ */
+ clear_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
+ remove_suspend_info(mddev, slot);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+ md_wakeup_thread(mddev->thread);
+ return;
+ }
+
+ /*
+ * The bitmaps are not same for different nodes
+ * if RESYNCING is happening in one node, then
+ * the node which received the RESYNCING message
+ * probably will perform resync with the region
+ * [lo, hi] again, so we could reduce resync time
+ * a lot if we can ensure that the bitmaps among
+ * different nodes are match up well.
+ *
+ * sync_low/hi is used to record the region which
+ * arrived in the previous RESYNCING message,
+ *
+ * Call bitmap_sync_with_cluster to clear
+ * NEEDED_MASK and set RESYNC_MASK since
+ * resync thread is running in another node,
+ * so we don't need to do the resync again
+ * with the same section */
+ md_bitmap_sync_with_cluster(mddev, cinfo->sync_low, cinfo->sync_hi, lo, hi);
+ cinfo->sync_low = lo;
+ cinfo->sync_hi = hi;
+
+ s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
+ if (!s)
+ return;
+ s->slot = slot;
+ s->lo = lo;
+ s->hi = hi;
+ mddev->pers->quiesce(mddev, 1);
+ spin_lock_irq(&cinfo->suspend_lock);
+ /* Remove existing entry (if exists) before adding */
+ __remove_suspend_info(cinfo, slot);
+ list_add(&s->list, &cinfo->suspend_list);
+ spin_unlock_irq(&cinfo->suspend_lock);
+ mddev->pers->quiesce(mddev, 0);
+}
+
+static void process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
+{
+ char disk_uuid[64];
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ char event_name[] = "EVENT=ADD_DEVICE";
+ char raid_slot[16];
+ char *envp[] = {event_name, disk_uuid, raid_slot, NULL};
+ int len;
+
+ len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
+ sprintf(disk_uuid + len, "%pU", cmsg->uuid);
+ snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
+ pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
+ init_completion(&cinfo->newdisk_completion);
+ set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
+ kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
+ wait_for_completion_timeout(&cinfo->newdisk_completion,
+ NEW_DEV_TIMEOUT);
+ clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
+}
+
+
+static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg)
+{
+ int got_lock = 0;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
+
+ dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
+ wait_event(mddev->thread->wqueue,
+ (got_lock = mddev_trylock(mddev)) ||
+ test_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state));
+ md_reload_sb(mddev, mddev->good_device_nr);
+ if (got_lock)
+ mddev_unlock(mddev);
+}
+
+static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
+{
+ struct md_rdev *rdev;
+
+ rcu_read_lock();
+ rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
+ if (rdev) {
+ set_bit(ClusterRemove, &rdev->flags);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+ md_wakeup_thread(mddev->thread);
+ }
+ else
+ pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
+ __func__, __LINE__, le32_to_cpu(msg->raid_slot));
+ rcu_read_unlock();
+}
+
+static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
+{
+ struct md_rdev *rdev;
+
+ rcu_read_lock();
+ rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
+ if (rdev && test_bit(Faulty, &rdev->flags))
+ clear_bit(Faulty, &rdev->flags);
+ else
+ pr_warn("%s: %d Could not find disk(%d) which is faulty",
+ __func__, __LINE__, le32_to_cpu(msg->raid_slot));
+ rcu_read_unlock();
+}
+
+static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
+{
+ int ret = 0;
+
+ if (WARN(mddev->cluster_info->slot_number - 1 == le32_to_cpu(msg->slot),
+ "node %d received it's own msg\n", le32_to_cpu(msg->slot)))
+ return -1;
+ switch (le32_to_cpu(msg->type)) {
+ case METADATA_UPDATED:
+ process_metadata_update(mddev, msg);
+ break;
+ case CHANGE_CAPACITY:
+ set_capacity(mddev->gendisk, mddev->array_sectors);
+ revalidate_disk(mddev->gendisk);
+ break;
+ case RESYNCING:
+ set_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
+ process_suspend_info(mddev, le32_to_cpu(msg->slot),
+ le64_to_cpu(msg->low),
+ le64_to_cpu(msg->high));
+ break;
+ case NEWDISK:
+ process_add_new_disk(mddev, msg);
+ break;
+ case REMOVE:
+ process_remove_disk(mddev, msg);
+ break;
+ case RE_ADD:
+ process_readd_disk(mddev, msg);
+ break;
+ case BITMAP_NEEDS_SYNC:
+ __recover_slot(mddev, le32_to_cpu(msg->slot));
+ break;
+ default:
+ ret = -1;
+ pr_warn("%s:%d Received unknown message from %d\n",
+ __func__, __LINE__, msg->slot);
+ }
+ return ret;
+}
+
+/*
+ * thread for receiving message
+ */
+static void recv_daemon(struct md_thread *thread)
+{
+ struct md_cluster_info *cinfo = thread->mddev->cluster_info;
+ struct dlm_lock_resource *ack_lockres = cinfo->ack_lockres;
+ struct dlm_lock_resource *message_lockres = cinfo->message_lockres;
+ struct cluster_msg msg;
+ int ret;
+
+ mutex_lock(&cinfo->recv_mutex);
+ /*get CR on Message*/
+ if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) {
+ pr_err("md/raid1:failed to get CR on MESSAGE\n");
+ mutex_unlock(&cinfo->recv_mutex);
+ return;
+ }
+
+ /* read lvb and wake up thread to process this message_lockres */
+ memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg));
+ ret = process_recvd_msg(thread->mddev, &msg);
+ if (ret)
+ goto out;
+
+ /*release CR on ack_lockres*/
+ ret = dlm_unlock_sync(ack_lockres);
+ if (unlikely(ret != 0))
+ pr_info("unlock ack failed return %d\n", ret);
+ /*up-convert to PR on message_lockres*/
+ ret = dlm_lock_sync(message_lockres, DLM_LOCK_PR);
+ if (unlikely(ret != 0))
+ pr_info("lock PR on msg failed return %d\n", ret);
+ /*get CR on ack_lockres again*/
+ ret = dlm_lock_sync(ack_lockres, DLM_LOCK_CR);
+ if (unlikely(ret != 0))
+ pr_info("lock CR on ack failed return %d\n", ret);
+out:
+ /*release CR on message_lockres*/
+ ret = dlm_unlock_sync(message_lockres);
+ if (unlikely(ret != 0))
+ pr_info("unlock msg failed return %d\n", ret);
+ mutex_unlock(&cinfo->recv_mutex);
+}
+
+/* lock_token()
+ * Takes the lock on the TOKEN lock resource so no other
+ * node can communicate while the operation is underway.
+ */
+static int lock_token(struct md_cluster_info *cinfo, bool mddev_locked)
+{
+ int error, set_bit = 0;
+ struct mddev *mddev = cinfo->mddev;
+
+ /*
+ * If resync thread run after raid1d thread, then process_metadata_update
+ * could not continue if raid1d held reconfig_mutex (and raid1d is blocked
+ * since another node already got EX on Token and waitting the EX of Ack),
+ * so let resync wake up thread in case flag is set.
+ */
+ if (mddev_locked && !test_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
+ &cinfo->state)) {
+ error = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
+ &cinfo->state);
+ WARN_ON_ONCE(error);
+ md_wakeup_thread(mddev->thread);
+ set_bit = 1;
+ }
+ error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
+ if (set_bit)
+ clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
+
+ if (error)
+ pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n",
+ __func__, __LINE__, error);
+
+ /* Lock the receive sequence */
+ mutex_lock(&cinfo->recv_mutex);
+ return error;
+}
+
+/* lock_comm()
+ * Sets the MD_CLUSTER_SEND_LOCK bit to lock the send channel.
+ */
+static int lock_comm(struct md_cluster_info *cinfo, bool mddev_locked)
+{
+ wait_event(cinfo->wait,
+ !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state));
+
+ return lock_token(cinfo, mddev_locked);
+}
+
+static void unlock_comm(struct md_cluster_info *cinfo)
+{
+ WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
+ mutex_unlock(&cinfo->recv_mutex);
+ dlm_unlock_sync(cinfo->token_lockres);
+ clear_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state);
+ wake_up(&cinfo->wait);
+}
+
+/* __sendmsg()
+ * This function performs the actual sending of the message. This function is
+ * usually called after performing the encompassing operation
+ * The function:
+ * 1. Grabs the message lockresource in EX mode
+ * 2. Copies the message to the message LVB
+ * 3. Downconverts message lockresource to CW
+ * 4. Upconverts ack lock resource from CR to EX. This forces the BAST on other nodes
+ * and the other nodes read the message. The thread will wait here until all other
+ * nodes have released ack lock resource.
+ * 5. Downconvert ack lockresource to CR
+ */
+static int __sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg)
+{
+ int error;
+ int slot = cinfo->slot_number - 1;
+
+ cmsg->slot = cpu_to_le32(slot);
+ /*get EX on Message*/
+ error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_EX);
+ if (error) {
+ pr_err("md-cluster: failed to get EX on MESSAGE (%d)\n", error);
+ goto failed_message;
+ }
+
+ memcpy(cinfo->message_lockres->lksb.sb_lvbptr, (void *)cmsg,
+ sizeof(struct cluster_msg));
+ /*down-convert EX to CW on Message*/
+ error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CW);
+ if (error) {
+ pr_err("md-cluster: failed to convert EX to CW on MESSAGE(%d)\n",
+ error);
+ goto failed_ack;
+ }
+
+ /*up-convert CR to EX on Ack*/
+ error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_EX);
+ if (error) {
+ pr_err("md-cluster: failed to convert CR to EX on ACK(%d)\n",
+ error);
+ goto failed_ack;
+ }
+
+ /*down-convert EX to CR on Ack*/
+ error = dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR);
+ if (error) {
+ pr_err("md-cluster: failed to convert EX to CR on ACK(%d)\n",
+ error);
+ goto failed_ack;
+ }
+
+failed_ack:
+ error = dlm_unlock_sync(cinfo->message_lockres);
+ if (unlikely(error != 0)) {
+ pr_err("md-cluster: failed convert to NL on MESSAGE(%d)\n",
+ error);
+ /* in case the message can't be released due to some reason */
+ goto failed_ack;
+ }
+failed_message:
+ return error;
+}
+
+static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg,
+ bool mddev_locked)
+{
+ int ret;
+
+ lock_comm(cinfo, mddev_locked);
+ ret = __sendmsg(cinfo, cmsg);
+ unlock_comm(cinfo);
+ return ret;
+}
+
+static int gather_all_resync_info(struct mddev *mddev, int total_slots)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ int i, ret = 0;
+ struct dlm_lock_resource *bm_lockres;
+ struct suspend_info *s;
+ char str[64];
+ sector_t lo, hi;
+
+
+ for (i = 0; i < total_slots; i++) {
+ memset(str, '\0', 64);
+ snprintf(str, 64, "bitmap%04d", i);
+ bm_lockres = lockres_init(mddev, str, NULL, 1);
+ if (!bm_lockres)
+ return -ENOMEM;
+ if (i == (cinfo->slot_number - 1)) {
+ lockres_free(bm_lockres);
+ continue;
+ }
+
+ bm_lockres->flags |= DLM_LKF_NOQUEUE;
+ ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
+ if (ret == -EAGAIN) {
+ s = read_resync_info(mddev, bm_lockres);
+ if (s) {
+ pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n",
+ __func__, __LINE__,
+ (unsigned long long) s->lo,
+ (unsigned long long) s->hi, i);
+ spin_lock_irq(&cinfo->suspend_lock);
+ s->slot = i;
+ list_add(&s->list, &cinfo->suspend_list);
+ spin_unlock_irq(&cinfo->suspend_lock);
+ }
+ ret = 0;
+ lockres_free(bm_lockres);
+ continue;
+ }
+ if (ret) {
+ lockres_free(bm_lockres);
+ goto out;
+ }
+
+ /* Read the disk bitmap sb and check if it needs recovery */
+ ret = md_bitmap_copy_from_slot(mddev, i, &lo, &hi, false);
+ if (ret) {
+ pr_warn("md-cluster: Could not gather bitmaps from slot %d", i);
+ lockres_free(bm_lockres);
+ continue;
+ }
+ if ((hi > 0) && (lo < mddev->recovery_cp)) {
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+ mddev->recovery_cp = lo;
+ md_check_recovery(mddev);
+ }
+
+ lockres_free(bm_lockres);
+ }
+out:
+ return ret;
+}
+
+static int join(struct mddev *mddev, int nodes)
+{
+ struct md_cluster_info *cinfo;
+ int ret, ops_rv;
+ char str[64];
+
+ cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL);
+ if (!cinfo)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&cinfo->suspend_list);
+ spin_lock_init(&cinfo->suspend_lock);
+ init_completion(&cinfo->completion);
+ set_bit(MD_CLUSTER_BEGIN_JOIN_CLUSTER, &cinfo->state);
+ init_waitqueue_head(&cinfo->wait);
+ mutex_init(&cinfo->recv_mutex);
+
+ mddev->cluster_info = cinfo;
+ cinfo->mddev = mddev;
+
+ memset(str, 0, 64);
+ sprintf(str, "%pU", mddev->uuid);
+ ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
+ DLM_LSFL_FS, LVB_SIZE,
+ &md_ls_ops, mddev, &ops_rv, &cinfo->lockspace);
+ if (ret)
+ goto err;
+ wait_for_completion(&cinfo->completion);
+ if (nodes < cinfo->slot_number) {
+ pr_err("md-cluster: Slot allotted(%d) is greater than available slots(%d).",
+ cinfo->slot_number, nodes);
+ ret = -ERANGE;
+ goto err;
+ }
+ /* Initiate the communication resources */
+ ret = -ENOMEM;
+ cinfo->recv_thread = md_register_thread(recv_daemon, mddev, "cluster_recv");
+ if (!cinfo->recv_thread) {
+ pr_err("md-cluster: cannot allocate memory for recv_thread!\n");
+ goto err;
+ }
+ cinfo->message_lockres = lockres_init(mddev, "message", NULL, 1);
+ if (!cinfo->message_lockres)
+ goto err;
+ cinfo->token_lockres = lockres_init(mddev, "token", NULL, 0);
+ if (!cinfo->token_lockres)
+ goto err;
+ cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0);
+ if (!cinfo->no_new_dev_lockres)
+ goto err;
+
+ ret = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX);
+ if (ret) {
+ ret = -EAGAIN;
+ pr_err("md-cluster: can't join cluster to avoid lock issue\n");
+ goto err;
+ }
+ cinfo->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0);
+ if (!cinfo->ack_lockres) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ /* get sync CR lock on ACK. */
+ if (dlm_lock_sync(cinfo->ack_lockres, DLM_LOCK_CR))
+ pr_err("md-cluster: failed to get a sync CR lock on ACK!(%d)\n",
+ ret);
+ dlm_unlock_sync(cinfo->token_lockres);
+ /* get sync CR lock on no-new-dev. */
+ if (dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR))
+ pr_err("md-cluster: failed to get a sync CR lock on no-new-dev!(%d)\n", ret);
+
+
+ pr_info("md-cluster: Joined cluster %s slot %d\n", str, cinfo->slot_number);
+ snprintf(str, 64, "bitmap%04d", cinfo->slot_number - 1);
+ cinfo->bitmap_lockres = lockres_init(mddev, str, NULL, 1);
+ if (!cinfo->bitmap_lockres) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) {
+ pr_err("Failed to get bitmap lock\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
+ if (!cinfo->resync_lockres) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ return 0;
+err:
+ set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
+ md_unregister_thread(&cinfo->recovery_thread);
+ md_unregister_thread(&cinfo->recv_thread);
+ lockres_free(cinfo->message_lockres);
+ lockres_free(cinfo->token_lockres);
+ lockres_free(cinfo->ack_lockres);
+ lockres_free(cinfo->no_new_dev_lockres);
+ lockres_free(cinfo->resync_lockres);
+ lockres_free(cinfo->bitmap_lockres);
+ if (cinfo->lockspace)
+ dlm_release_lockspace(cinfo->lockspace, 2);
+ mddev->cluster_info = NULL;
+ kfree(cinfo);
+ return ret;
+}
+
+static void load_bitmaps(struct mddev *mddev, int total_slots)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ /* load all the node's bitmap info for resync */
+ if (gather_all_resync_info(mddev, total_slots))
+ pr_err("md-cluster: failed to gather all resyn infos\n");
+ set_bit(MD_CLUSTER_ALREADY_IN_CLUSTER, &cinfo->state);
+ /* wake up recv thread in case something need to be handled */
+ if (test_and_clear_bit(MD_CLUSTER_PENDING_RECV_EVENT, &cinfo->state))
+ md_wakeup_thread(cinfo->recv_thread);
+}
+
+static void resync_bitmap(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct cluster_msg cmsg = {0};
+ int err;
+
+ cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
+ err = sendmsg(cinfo, &cmsg, 1);
+ if (err)
+ pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
+ __func__, __LINE__, err);
+}
+
+static void unlock_all_bitmaps(struct mddev *mddev);
+static int leave(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ if (!cinfo)
+ return 0;
+
+ /* BITMAP_NEEDS_SYNC message should be sent when node
+ * is leaving the cluster with dirty bitmap, also we
+ * can only deliver it when dlm connection is available */
+ if (cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector)
+ resync_bitmap(mddev);
+
+ set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
+ md_unregister_thread(&cinfo->recovery_thread);
+ md_unregister_thread(&cinfo->recv_thread);
+ lockres_free(cinfo->message_lockres);
+ lockres_free(cinfo->token_lockres);
+ lockres_free(cinfo->ack_lockres);
+ lockres_free(cinfo->no_new_dev_lockres);
+ lockres_free(cinfo->resync_lockres);
+ lockres_free(cinfo->bitmap_lockres);
+ unlock_all_bitmaps(mddev);
+ dlm_release_lockspace(cinfo->lockspace, 2);
+ kfree(cinfo);
+ return 0;
+}
+
+/* slot_number(): Returns the MD slot number to use
+ * DLM starts the slot numbers from 1, wheras cluster-md
+ * wants the number to be from zero, so we deduct one
+ */
+static int slot_number(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ return cinfo->slot_number - 1;
+}
+
+/*
+ * Check if the communication is already locked, else lock the communication
+ * channel.
+ * If it is already locked, token is in EX mode, and hence lock_token()
+ * should not be called.
+ */
+static int metadata_update_start(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ int ret;
+
+ /*
+ * metadata_update_start is always called with the protection of
+ * reconfig_mutex, so set WAITING_FOR_TOKEN here.
+ */
+ ret = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
+ &cinfo->state);
+ WARN_ON_ONCE(ret);
+ md_wakeup_thread(mddev->thread);
+
+ wait_event(cinfo->wait,
+ !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state) ||
+ test_and_clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state));
+
+ /* If token is already locked, return 0 */
+ if (cinfo->token_lockres->mode == DLM_LOCK_EX) {
+ clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
+ return 0;
+ }
+
+ ret = lock_token(cinfo, 1);
+ clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);
+ return ret;
+}
+
+static int metadata_update_finish(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct cluster_msg cmsg;
+ struct md_rdev *rdev;
+ int ret = 0;
+ int raid_slot = -1;
+
+ memset(&cmsg, 0, sizeof(cmsg));
+ cmsg.type = cpu_to_le32(METADATA_UPDATED);
+ /* Pick up a good active device number to send.
+ */
+ rdev_for_each(rdev, mddev)
+ if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) {
+ raid_slot = rdev->desc_nr;
+ break;
+ }
+ if (raid_slot >= 0) {
+ cmsg.raid_slot = cpu_to_le32(raid_slot);
+ ret = __sendmsg(cinfo, &cmsg);
+ } else
+ pr_warn("md-cluster: No good device id found to send\n");
+ clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
+ unlock_comm(cinfo);
+ return ret;
+}
+
+static void metadata_update_cancel(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
+ unlock_comm(cinfo);
+}
+
+/*
+ * return 0 if all the bitmaps have the same sync_size
+ */
+static int cluster_check_sync_size(struct mddev *mddev)
+{
+ int i, rv;
+ bitmap_super_t *sb;
+ unsigned long my_sync_size, sync_size = 0;
+ int node_num = mddev->bitmap_info.nodes;
+ int current_slot = md_cluster_ops->slot_number(mddev);
+ struct bitmap *bitmap = mddev->bitmap;
+ char str[64];
+ struct dlm_lock_resource *bm_lockres;
+
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ my_sync_size = sb->sync_size;
+ kunmap_atomic(sb);
+
+ for (i = 0; i < node_num; i++) {
+ if (i == current_slot)
+ continue;
+
+ bitmap = get_bitmap_from_slot(mddev, i);
+ if (IS_ERR(bitmap)) {
+ pr_err("can't get bitmap from slot %d\n", i);
+ return -1;
+ }
+
+ /*
+ * If we can hold the bitmap lock of one node then
+ * the slot is not occupied, update the sb.
+ */
+ snprintf(str, 64, "bitmap%04d", i);
+ bm_lockres = lockres_init(mddev, str, NULL, 1);
+ if (!bm_lockres) {
+ pr_err("md-cluster: Cannot initialize %s\n", str);
+ md_bitmap_free(bitmap);
+ return -1;
+ }
+ bm_lockres->flags |= DLM_LKF_NOQUEUE;
+ rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
+ if (!rv)
+ md_bitmap_update_sb(bitmap);
+ lockres_free(bm_lockres);
+
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ if (sync_size == 0)
+ sync_size = sb->sync_size;
+ else if (sync_size != sb->sync_size) {
+ kunmap_atomic(sb);
+ md_bitmap_free(bitmap);
+ return -1;
+ }
+ kunmap_atomic(sb);
+ md_bitmap_free(bitmap);
+ }
+
+ return (my_sync_size == sync_size) ? 0 : -1;
+}
+
+/*
+ * Update the size for cluster raid is a little more complex, we perform it
+ * by the steps:
+ * 1. hold token lock and update superblock in initiator node.
+ * 2. send METADATA_UPDATED msg to other nodes.
+ * 3. The initiator node continues to check each bitmap's sync_size, if all
+ * bitmaps have the same value of sync_size, then we can set capacity and
+ * let other nodes to perform it. If one node can't update sync_size
+ * accordingly, we need to revert to previous value.
+ */
+static void update_size(struct mddev *mddev, sector_t old_dev_sectors)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct cluster_msg cmsg;
+ struct md_rdev *rdev;
+ int ret = 0;
+ int raid_slot = -1;
+
+ md_update_sb(mddev, 1);
+ lock_comm(cinfo, 1);
+
+ memset(&cmsg, 0, sizeof(cmsg));
+ cmsg.type = cpu_to_le32(METADATA_UPDATED);
+ rdev_for_each(rdev, mddev)
+ if (rdev->raid_disk >= 0 && !test_bit(Faulty, &rdev->flags)) {
+ raid_slot = rdev->desc_nr;
+ break;
+ }
+ if (raid_slot >= 0) {
+ cmsg.raid_slot = cpu_to_le32(raid_slot);
+ /*
+ * We can only change capiticy after all the nodes can do it,
+ * so need to wait after other nodes already received the msg
+ * and handled the change
+ */
+ ret = __sendmsg(cinfo, &cmsg);
+ if (ret) {
+ pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",
+ __func__, __LINE__);
+ unlock_comm(cinfo);
+ return;
+ }
+ } else {
+ pr_err("md-cluster: No good device id found to send\n");
+ unlock_comm(cinfo);
+ return;
+ }
+
+ /*
+ * check the sync_size from other node's bitmap, if sync_size
+ * have already updated in other nodes as expected, send an
+ * empty metadata msg to permit the change of capacity
+ */
+ if (cluster_check_sync_size(mddev) == 0) {
+ memset(&cmsg, 0, sizeof(cmsg));
+ cmsg.type = cpu_to_le32(CHANGE_CAPACITY);
+ ret = __sendmsg(cinfo, &cmsg);
+ if (ret)
+ pr_err("%s:%d: failed to send CHANGE_CAPACITY msg\n",
+ __func__, __LINE__);
+ set_capacity(mddev->gendisk, mddev->array_sectors);
+ revalidate_disk(mddev->gendisk);
+ } else {
+ /* revert to previous sectors */
+ ret = mddev->pers->resize(mddev, old_dev_sectors);
+ if (!ret)
+ revalidate_disk(mddev->gendisk);
+ ret = __sendmsg(cinfo, &cmsg);
+ if (ret)
+ pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",
+ __func__, __LINE__);
+ }
+ unlock_comm(cinfo);
+}
+
+static int resync_start(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ return dlm_lock_sync_interruptible(cinfo->resync_lockres, DLM_LOCK_EX, mddev);
+}
+
+static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct resync_info ri;
+ struct cluster_msg cmsg = {0};
+
+ /* do not send zero again, if we have sent before */
+ if (hi == 0) {
+ memcpy(&ri, cinfo->bitmap_lockres->lksb.sb_lvbptr, sizeof(struct resync_info));
+ if (le64_to_cpu(ri.hi) == 0)
+ return 0;
+ }
+
+ add_resync_info(cinfo->bitmap_lockres, lo, hi);
+ /* Re-acquire the lock to refresh LVB */
+ dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
+ cmsg.type = cpu_to_le32(RESYNCING);
+ cmsg.low = cpu_to_le64(lo);
+ cmsg.high = cpu_to_le64(hi);
+
+ /*
+ * mddev_lock is held if resync_info_update is called from
+ * resync_finish (md_reap_sync_thread -> resync_finish)
+ */
+ if (lo == 0 && hi == 0)
+ return sendmsg(cinfo, &cmsg, 1);
+ else
+ return sendmsg(cinfo, &cmsg, 0);
+}
+
+static int resync_finish(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ int ret = 0;
+
+ clear_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
+
+ /*
+ * If resync thread is interrupted so we can't say resync is finished,
+ * another node will launch resync thread to continue.
+ */
+ if (!test_bit(MD_CLOSING, &mddev->flags))
+ ret = resync_info_update(mddev, 0, 0);
+ dlm_unlock_sync(cinfo->resync_lockres);
+ return ret;
+}
+
+static int area_resyncing(struct mddev *mddev, int direction,
+ sector_t lo, sector_t hi)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ int ret = 0;
+ struct suspend_info *s;
+
+ if ((direction == READ) &&
+ test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state))
+ return 1;
+
+ spin_lock_irq(&cinfo->suspend_lock);
+ if (list_empty(&cinfo->suspend_list))
+ goto out;
+ list_for_each_entry(s, &cinfo->suspend_list, list)
+ if (hi > s->lo && lo < s->hi) {
+ ret = 1;
+ break;
+ }
+out:
+ spin_unlock_irq(&cinfo->suspend_lock);
+ return ret;
+}
+
+/* add_new_disk() - initiates a disk add
+ * However, if this fails before writing md_update_sb(),
+ * add_new_disk_cancel() must be called to release token lock
+ */
+static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ struct cluster_msg cmsg;
+ int ret = 0;
+ struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
+ char *uuid = sb->device_uuid;
+
+ memset(&cmsg, 0, sizeof(cmsg));
+ cmsg.type = cpu_to_le32(NEWDISK);
+ memcpy(cmsg.uuid, uuid, 16);
+ cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
+ lock_comm(cinfo, 1);
+ ret = __sendmsg(cinfo, &cmsg);
+ if (ret) {
+ unlock_comm(cinfo);
+ return ret;
+ }
+ cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
+ ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
+ cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;
+ /* Some node does not "see" the device */
+ if (ret == -EAGAIN)
+ ret = -ENOENT;
+ if (ret)
+ unlock_comm(cinfo);
+ else {
+ dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
+ /* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
+ * will run soon after add_new_disk, the below path will be
+ * invoked:
+ * md_wakeup_thread(mddev->thread)
+ * -> conf->thread (raid1d)
+ * -> md_check_recovery -> md_update_sb
+ * -> metadata_update_start/finish
+ * MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
+ *
+ * For other failure cases, metadata_update_cancel and
+ * add_new_disk_cancel also clear below bit as well.
+ * */
+ set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
+ wake_up(&cinfo->wait);
+ }
+ return ret;
+}
+
+static void add_new_disk_cancel(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ clear_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
+ unlock_comm(cinfo);
+}
+
+static int new_disk_ack(struct mddev *mddev, bool ack)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
+ pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
+ return -EINVAL;
+ }
+
+ if (ack)
+ dlm_unlock_sync(cinfo->no_new_dev_lockres);
+ complete(&cinfo->newdisk_completion);
+ return 0;
+}
+
+static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
+{
+ struct cluster_msg cmsg = {0};
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ cmsg.type = cpu_to_le32(REMOVE);
+ cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
+ return sendmsg(cinfo, &cmsg, 1);
+}
+
+static int lock_all_bitmaps(struct mddev *mddev)
+{
+ int slot, my_slot, ret, held = 1, i = 0;
+ char str[64];
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ cinfo->other_bitmap_lockres =
+ kcalloc(mddev->bitmap_info.nodes - 1,
+ sizeof(struct dlm_lock_resource *), GFP_KERNEL);
+ if (!cinfo->other_bitmap_lockres) {
+ pr_err("md: can't alloc mem for other bitmap locks\n");
+ return 0;
+ }
+
+ my_slot = slot_number(mddev);
+ for (slot = 0; slot < mddev->bitmap_info.nodes; slot++) {
+ if (slot == my_slot)
+ continue;
+
+ memset(str, '\0', 64);
+ snprintf(str, 64, "bitmap%04d", slot);
+ cinfo->other_bitmap_lockres[i] = lockres_init(mddev, str, NULL, 1);
+ if (!cinfo->other_bitmap_lockres[i])
+ return -ENOMEM;
+
+ cinfo->other_bitmap_lockres[i]->flags |= DLM_LKF_NOQUEUE;
+ ret = dlm_lock_sync(cinfo->other_bitmap_lockres[i], DLM_LOCK_PW);
+ if (ret)
+ held = -1;
+ i++;
+ }
+
+ return held;
+}
+
+static void unlock_all_bitmaps(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ int i;
+
+ /* release other node's bitmap lock if they are existed */
+ if (cinfo->other_bitmap_lockres) {
+ for (i = 0; i < mddev->bitmap_info.nodes - 1; i++) {
+ if (cinfo->other_bitmap_lockres[i]) {
+ lockres_free(cinfo->other_bitmap_lockres[i]);
+ }
+ }
+ kfree(cinfo->other_bitmap_lockres);
+ }
+}
+
+static int gather_bitmaps(struct md_rdev *rdev)
+{
+ int sn, err;
+ sector_t lo, hi;
+ struct cluster_msg cmsg = {0};
+ struct mddev *mddev = rdev->mddev;
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+
+ cmsg.type = cpu_to_le32(RE_ADD);
+ cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
+ err = sendmsg(cinfo, &cmsg, 1);
+ if (err)
+ goto out;
+
+ for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
+ if (sn == (cinfo->slot_number - 1))
+ continue;
+ err = md_bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
+ if (err) {
+ pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
+ goto out;
+ }
+ if ((hi > 0) && (lo < mddev->recovery_cp))
+ mddev->recovery_cp = lo;
+ }
+out:
+ return err;
+}
+
+static struct md_cluster_operations cluster_ops = {
+ .join = join,
+ .leave = leave,
+ .slot_number = slot_number,
+ .resync_start = resync_start,
+ .resync_finish = resync_finish,
+ .resync_info_update = resync_info_update,
+ .metadata_update_start = metadata_update_start,
+ .metadata_update_finish = metadata_update_finish,
+ .metadata_update_cancel = metadata_update_cancel,
+ .area_resyncing = area_resyncing,
+ .add_new_disk = add_new_disk,
+ .add_new_disk_cancel = add_new_disk_cancel,
+ .new_disk_ack = new_disk_ack,
+ .remove_disk = remove_disk,
+ .load_bitmaps = load_bitmaps,
+ .gather_bitmaps = gather_bitmaps,
+ .lock_all_bitmaps = lock_all_bitmaps,
+ .unlock_all_bitmaps = unlock_all_bitmaps,
+ .update_size = update_size,
+};
+
+static int __init cluster_init(void)
+{
+ pr_warn("md-cluster: support raid1 and raid10 (limited support)\n");
+ pr_info("Registering Cluster MD functions\n");
+ register_md_cluster_operations(&cluster_ops, THIS_MODULE);
+ return 0;
+}
+
+static void cluster_exit(void)
+{
+ unregister_md_cluster_operations();
+}
+
+module_init(cluster_init);
+module_exit(cluster_exit);
+MODULE_AUTHOR("SUSE");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Clustering support for MD");