diff options
Diffstat (limited to 'drivers/md/md-cluster.c')
| -rw-r--r-- | drivers/md/md-cluster.c | 1607 |
1 files changed, 1607 insertions, 0 deletions
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c new file mode 100644 index 0000000000..1e26eb2233 --- /dev/null +++ b/drivers/md/md-cluster.c @@ -0,0 +1,1607 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2015, SUSE + */ + + +#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 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 + * accommodate 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; + /* record the region which write should be suspended */ + sector_t suspend_lo; + sector_t suspend_hi; + int suspend_from; /* the slot which broadcast suspend_lo/hi */ + + struct md_thread __rcu *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 __rcu *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, + BITMAP_RESIZE, +}; + +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; + } + strscpy(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 int read_resync_info(struct mddev *mddev, + struct dlm_lock_resource *lockres) +{ + struct resync_info ri; + struct md_cluster_info *cinfo = mddev->cluster_info; + int ret = 0; + + dlm_lock_sync(lockres, DLM_LOCK_CR); + memcpy(&ri, lockres->lksb.sb_lvbptr, sizeof(struct resync_info)); + if (le64_to_cpu(ri.hi) > 0) { + cinfo->suspend_hi = le64_to_cpu(ri.hi); + cinfo->suspend_lo = le64_to_cpu(ri.lo); + ret = 1; + } + dlm_unlock_sync(lockres); + return ret; +} + +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; + 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); + cinfo->suspend_hi = 0; + cinfo->suspend_lo = 0; + cinfo->suspend_from = -1; + spin_unlock_irq(&cinfo->suspend_lock); + + /* Kick off a reshape if needed */ + if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) && + test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) && + mddev->reshape_position != MaxSector) + md_wakeup_thread(mddev->sync_thread); + + 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) { + rcu_assign_pointer(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 mddev *mddev, int slot) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + mddev->pers->quiesce(mddev, 1); + spin_lock_irq(&cinfo->suspend_lock); + cinfo->suspend_hi = 0; + cinfo->suspend_lo = 0; + 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 mdp_superblock_1 *sb = NULL; + struct md_rdev *rdev; + + 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; + } + + rdev_for_each(rdev, mddev) + if (rdev->raid_disk > -1 && !test_bit(Faulty, &rdev->flags)) { + sb = page_address(rdev->sb_page); + break; + } + + /* + * 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 md_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. + * + * Skip md_bitmap_sync_with_cluster in case reshape + * happening, because reshaping region is small and + * we don't want to trigger lots of WARN. + */ + if (sb && !(le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) + md_bitmap_sync_with_cluster(mddev, cinfo->sync_low, + cinfo->sync_hi, lo, hi); + cinfo->sync_low = lo; + cinfo->sync_hi = hi; + + mddev->pers->quiesce(mddev, 1); + spin_lock_irq(&cinfo->suspend_lock); + cinfo->suspend_from = slot; + cinfo->suspend_lo = lo; + cinfo->suspend_hi = hi; + 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_thread *thread; + 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); + + /* daemaon thread must exist */ + thread = rcu_dereference_protected(mddev->thread, true); + wait_event(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 its 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_and_notify(mddev->gendisk, mddev->array_sectors); + 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; + case BITMAP_RESIZE: + if (le64_to_cpu(msg->high) != mddev->pers->size(mddev, 0, 0)) + ret = md_bitmap_resize(mddev->bitmap, + le64_to_cpu(msg->high), 0, 0); + 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) +{ + int error; + + error = dlm_lock_sync(cinfo->token_lockres, DLM_LOCK_EX); + if (error) { + pr_err("md-cluster(%s:%d): failed to get EX on TOKEN (%d)\n", + __func__, __LINE__, error); + } else { + /* 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) +{ + int rv, 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 waiting 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)) { + rv = test_and_set_bit_lock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, + &cinfo->state); + WARN_ON_ONCE(rv); + md_wakeup_thread(mddev->thread); + set_bit = 1; + } + + wait_event(cinfo->wait, + !test_and_set_bit(MD_CLUSTER_SEND_LOCK, &cinfo->state)); + rv = lock_token(cinfo); + if (set_bit) + clear_bit_unlock(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state); + return rv; +} + +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; + + ret = lock_comm(cinfo, mddev_locked); + if (!ret) { + 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; + 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) { + if (read_resync_info(mddev, bm_lockres)) { + pr_info("%s:%d Resync[%llu..%llu] in progress on %d\n", + __func__, __LINE__, + (unsigned long long) cinfo->suspend_lo, + (unsigned long long) cinfo->suspend_hi, + i); + cinfo->suspend_from = i; + } + 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, + 0, 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; + rcu_assign_pointer(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(mddev, &cinfo->recovery_thread); + md_unregister_thread(mddev, &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. + * + * Also, we should send BITMAP_NEEDS_SYNC message in + * case reshaping is interrupted. + */ + if ((cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector) || + (mddev->reshape_position != MaxSector && + test_bit(MD_CLOSING, &mddev->flags))) + resync_bitmap(mddev); + + set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state); + md_unregister_thread(mddev, &cinfo->recovery_thread); + md_unregister_thread(mddev, &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); + 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); +} + +static int update_bitmap_size(struct mddev *mddev, sector_t size) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + struct cluster_msg cmsg = {0}; + int ret; + + cmsg.type = cpu_to_le32(BITMAP_RESIZE); + cmsg.high = cpu_to_le64(size); + ret = sendmsg(cinfo, &cmsg, 0); + if (ret) + pr_err("%s:%d: failed to send BITMAP_RESIZE message (%d)\n", + __func__, __LINE__, ret); + return ret; +} + +static int resize_bitmaps(struct mddev *mddev, sector_t newsize, sector_t oldsize) +{ + struct bitmap_counts *counts; + char str[64]; + struct dlm_lock_resource *bm_lockres; + struct bitmap *bitmap = mddev->bitmap; + unsigned long my_pages = bitmap->counts.pages; + int i, rv; + + /* + * We need to ensure all the nodes can grow to a larger + * bitmap size before make the reshaping. + */ + rv = update_bitmap_size(mddev, newsize); + if (rv) + return rv; + + for (i = 0; i < mddev->bitmap_info.nodes; i++) { + if (i == md_cluster_ops->slot_number(mddev)) + continue; + + bitmap = get_bitmap_from_slot(mddev, i); + if (IS_ERR(bitmap)) { + pr_err("can't get bitmap from slot %d\n", i); + bitmap = NULL; + goto out; + } + counts = &bitmap->counts; + + /* + * If we can hold the bitmap lock of one node then + * the slot is not occupied, update the pages. + */ + snprintf(str, 64, "bitmap%04d", i); + bm_lockres = lockres_init(mddev, str, NULL, 1); + if (!bm_lockres) { + pr_err("Cannot initialize %s lock\n", str); + goto out; + } + bm_lockres->flags |= DLM_LKF_NOQUEUE; + rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW); + if (!rv) + counts->pages = my_pages; + lockres_free(bm_lockres); + + if (my_pages != counts->pages) + /* + * Let's revert the bitmap size if one node + * can't resize bitmap + */ + goto out; + md_bitmap_free(bitmap); + } + + return 0; +out: + md_bitmap_free(bitmap); + update_bitmap_size(mddev, oldsize); + return -1; +} + +/* + * 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); + if (lock_comm(cinfo, 1)) { + pr_err("%s: lock_comm failed\n", __func__); + return; + } + + 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_and_notify(mddev->gendisk, mddev->array_sectors); + } else { + /* revert to previous sectors */ + ret = mddev->pers->resize(mddev, old_dev_sectors); + 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 void resync_info_get(struct mddev *mddev, sector_t *lo, sector_t *hi) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + + spin_lock_irq(&cinfo->suspend_lock); + *lo = cinfo->suspend_lo; + *hi = cinfo->suspend_hi; + spin_unlock_irq(&cinfo->suspend_lock); +} + +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; + + if ((direction == READ) && + test_bit(MD_CLUSTER_SUSPEND_READ_BALANCING, &cinfo->state)) + return 1; + + spin_lock_irq(&cinfo->suspend_lock); + if (hi > cinfo->suspend_lo && lo < cinfo->suspend_hi) + ret = 1; + 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); + if (lock_comm(cinfo, 1)) + return -EAGAIN; + 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); + cinfo->other_bitmap_lockres = NULL; + } +} + +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, + .resync_info_get = resync_info_get, + .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, + .resize_bitmaps = resize_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"); |