diff options
Diffstat (limited to 'kernel/drivers/md/md-cluster.c')
| -rw-r--r-- | kernel/drivers/md/md-cluster.c | 965 |
1 files changed, 965 insertions, 0 deletions
diff --git a/kernel/drivers/md/md-cluster.c b/kernel/drivers/md/md-cluster.c new file mode 100644 index 000000000..fcfc4b9b2 --- /dev/null +++ b/kernel/drivers/md/md-cluster.c @@ -0,0 +1,965 @@ +/* + * 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/dlm.h> +#include <linux/sched.h> +#include <linux/raid/md_p.h> +#include "md.h" +#include "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() */ + struct completion completion; /* completion for synchronized locking */ + void (*bast)(void *arg, int mode); /* blocking AST function pointer*/ + struct mddev *mddev; /* pointing back to mddev. */ +}; + +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 + + +struct md_cluster_info { + /* dlm lock space and resources for clustered raid. */ + dlm_lockspace_t *lockspace; + int slot_number; + struct completion completion; + struct dlm_lock_resource *sb_lock; + struct mutex sb_mutex; + struct dlm_lock_resource *bitmap_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; + unsigned long state; +}; + +enum msg_type { + METADATA_UPDATED = 0, + RESYNCING, + NEWDISK, + REMOVE, + RE_ADD, +}; + +struct cluster_msg { + int type; + int slot; + /* TODO: Unionize this for smaller footprint */ + sector_t low; + sector_t high; + char uuid[16]; + int raid_slot; +}; + +static void sync_ast(void *arg) +{ + struct dlm_lock_resource *res; + + res = (struct dlm_lock_resource *) arg; + complete(&res->completion); +} + +static int dlm_lock_sync(struct dlm_lock_resource *res, int mode) +{ + int ret = 0; + + init_completion(&res->completion); + 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_for_completion(&res->completion); + return res->lksb.sb_status; +} + +static int dlm_unlock_sync(struct dlm_lock_resource *res) +{ + return dlm_lock_sync(res, DLM_LOCK_NL); +} + +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; + res->ls = cinfo->lockspace; + res->mddev = mddev; + 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) +{ + if (!res) + return; + + init_completion(&res->completion); + dlm_unlock(res->ls, res->lksb.sb_lkid, 0, &res->lksb, res); + wait_for_completion(&res->completion); + + kfree(res->name); + kfree(res->lksb.sb_lvbptr); + kfree(res); +} + +static char *pretty_uuid(char *dest, char *src) +{ + int i, len = 0; + + for (i = 0; i < 16; i++) { + if (i == 4 || i == 6 || i == 8 || i == 10) + len += sprintf(dest + len, "-"); + len += sprintf(dest + len, "%02x", (__u8)src[i]); + } + return dest; +} + +static void add_resync_info(struct mddev *mddev, 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 (ri.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; + + /* 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); + + 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(bm_lockres, DLM_LOCK_PW); + if (ret) { + pr_err("md-cluster: Could not DLM lock %s: %d\n", + str, ret); + goto clear_bit; + } + ret = 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 dlm_unlock; + } + if (hi > 0) { + /* TODO:Wait for current resync to get over */ + set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); + if (lo < mddev->recovery_cp) + mddev->recovery_cp = lo; + md_check_recovery(mddev); + } +dlm_unlock: + dlm_unlock_sync(bm_lockres); +clear_bit: + clear_bit(slot, &cinfo->recovery_map); + } +} + +static void recover_prep(void *arg) +{ +} + +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); + set_bit(slot->slot - 1, &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_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; + complete(&cinfo->completion); +} + +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 = (struct dlm_lock_resource *)arg; + struct md_cluster_info *cinfo = res->mddev->cluster_info; + + if (mode == DLM_LOCK_EX) + md_wakeup_thread(cinfo->recv_thread); +} + +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) { + pr_info("%s:%d Deleting suspend_info: %d\n", + __func__, __LINE__, slot); + list_del(&s->list); + kfree(s); + break; + } +} + +static void remove_suspend_info(struct md_cluster_info *cinfo, int slot) +{ + spin_lock_irq(&cinfo->suspend_lock); + __remove_suspend_info(cinfo, slot); + spin_unlock_irq(&cinfo->suspend_lock); +} + + +static void process_suspend_info(struct md_cluster_info *cinfo, + int slot, sector_t lo, sector_t hi) +{ + struct suspend_info *s; + + if (!hi) { + remove_suspend_info(cinfo, slot); + return; + } + s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL); + if (!s) + return; + s->slot = slot; + s->lo = lo; + s->hi = hi; + 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); +} + +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="); + pretty_uuid(disk_uuid + len, cmsg->uuid); + snprintf(raid_slot, 16, "RAID_DISK=%d", 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) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + + md_reload_sb(mddev); + dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR); +} + +static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg) +{ + struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev, msg->raid_slot); + + if (rdev) + md_kick_rdev_from_array(rdev); + else + pr_warn("%s: %d Could not find disk(%d) to REMOVE\n", __func__, __LINE__, msg->raid_slot); +} + +static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg) +{ + struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev, 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__, msg->raid_slot); +} + +static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg) +{ + switch (msg->type) { + case METADATA_UPDATED: + pr_info("%s: %d Received message: METADATA_UPDATE from %d\n", + __func__, __LINE__, msg->slot); + process_metadata_update(mddev, msg); + break; + case RESYNCING: + pr_info("%s: %d Received message: RESYNCING from %d\n", + __func__, __LINE__, msg->slot); + process_suspend_info(mddev->cluster_info, msg->slot, + msg->low, msg->high); + break; + case NEWDISK: + pr_info("%s: %d Received message: NEWDISK from %d\n", + __func__, __LINE__, msg->slot); + process_add_new_disk(mddev, msg); + break; + case REMOVE: + pr_info("%s: %d Received REMOVE from %d\n", + __func__, __LINE__, msg->slot); + process_remove_disk(mddev, msg); + break; + case RE_ADD: + pr_info("%s: %d Received RE_ADD from %d\n", + __func__, __LINE__, msg->slot); + process_readd_disk(mddev, msg); + break; + default: + pr_warn("%s:%d Received unknown message from %d\n", + __func__, __LINE__, msg->slot); + } +} + +/* + * 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; + + /*get CR on Message*/ + if (dlm_lock_sync(message_lockres, DLM_LOCK_CR)) { + pr_err("md/raid1:failed to get CR on MESSAGE\n"); + return; + } + + /* read lvb and wake up thread to process this message_lockres */ + memcpy(&msg, message_lockres->lksb.sb_lvbptr, sizeof(struct cluster_msg)); + process_recvd_msg(thread->mddev, &msg); + + /*release CR on ack_lockres*/ + dlm_unlock_sync(ack_lockres); + /*up-convert to EX on message_lockres*/ + dlm_lock_sync(message_lockres, DLM_LOCK_EX); + /*get CR on ack_lockres again*/ + dlm_lock_sync(ack_lockres, DLM_LOCK_CR); + /*release CR on message_lockres*/ + dlm_unlock_sync(message_lockres); +} + +/* lock_comm() + * Takes the lock on the TOKEN lock resource so no other + * node can communicate while the operation is underway. + */ +static int lock_comm(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); + return error; +} + +static void unlock_comm(struct md_cluster_info *cinfo) +{ + dlm_unlock_sync(cinfo->token_lockres); +} + +/* __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 CR + * 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 CR on Message*/ + error = dlm_lock_sync(cinfo->message_lockres, DLM_LOCK_CR); + if (error) { + pr_err("md-cluster: failed to convert EX to CR on MESSAGE(%d)\n", + error); + goto failed_message; + } + + /*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: + dlm_unlock_sync(cinfo->message_lockres); +failed_message: + return error; +} + +static int sendmsg(struct md_cluster_info *cinfo, struct cluster_msg *cmsg) +{ + int ret; + + lock_comm(cinfo); + 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]; + + + 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)) + continue; + + bm_lockres->flags |= DLM_LKF_NOQUEUE; + ret = dlm_lock_sync(bm_lockres, DLM_LOCK_PW); + if (ret == -EAGAIN) { + memset(bm_lockres->lksb.sb_lvbptr, '\0', LVB_SIZE); + 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) + goto out; + /* TODO: Read the disk bitmap sb and check if it needs recovery */ + dlm_unlock_sync(bm_lockres); + 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]; + + if (!try_module_get(THIS_MODULE)) + return -ENOENT; + + cinfo = kzalloc(sizeof(struct md_cluster_info), GFP_KERNEL); + if (!cinfo) + return -ENOMEM; + + init_completion(&cinfo->completion); + + mutex_init(&cinfo->sb_mutex); + mddev->cluster_info = cinfo; + + memset(str, 0, 64); + pretty_uuid(str, 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; + } + cinfo->sb_lock = lockres_init(mddev, "cmd-super", + NULL, 0); + if (!cinfo->sb_lock) { + ret = -ENOMEM; + 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->ack_lockres = lockres_init(mddev, "ack", ack_bast, 0); + if (!cinfo->ack_lockres) + goto err; + cinfo->no_new_dev_lockres = lockres_init(mddev, "no-new-dev", NULL, 0); + if (!cinfo->no_new_dev_lockres) + 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); + /* 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) + goto err; + if (dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW)) { + pr_err("Failed to get bitmap lock\n"); + ret = -EINVAL; + goto err; + } + + INIT_LIST_HEAD(&cinfo->suspend_list); + spin_lock_init(&cinfo->suspend_lock); + + ret = gather_all_resync_info(mddev, nodes); + if (ret) + goto err; + + return 0; +err: + 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->bitmap_lockres); + lockres_free(cinfo->sb_lock); + if (cinfo->lockspace) + dlm_release_lockspace(cinfo->lockspace, 2); + mddev->cluster_info = NULL; + kfree(cinfo); + module_put(THIS_MODULE); + return ret; +} + +static int leave(struct mddev *mddev) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + + if (!cinfo) + return 0; + 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->sb_lock); + lockres_free(cinfo->bitmap_lockres); + dlm_release_lockspace(cinfo->lockspace, 2); + 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; +} + +static void resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + + add_resync_info(mddev, cinfo->bitmap_lockres, lo, hi); + /* Re-acquire the lock to refresh LVB */ + dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW); +} + +static int metadata_update_start(struct mddev *mddev) +{ + return lock_comm(mddev->cluster_info); +} + +static int metadata_update_finish(struct mddev *mddev) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + struct cluster_msg cmsg; + int ret; + + memset(&cmsg, 0, sizeof(cmsg)); + cmsg.type = cpu_to_le32(METADATA_UPDATED); + ret = __sendmsg(cinfo, &cmsg); + unlock_comm(cinfo); + return ret; +} + +static int metadata_update_cancel(struct mddev *mddev) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + + return dlm_unlock_sync(cinfo->token_lockres); +} + +static int resync_send(struct mddev *mddev, enum msg_type type, + sector_t lo, sector_t hi) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + struct cluster_msg cmsg; + int slot = cinfo->slot_number - 1; + + pr_info("%s:%d lo: %llu hi: %llu\n", __func__, __LINE__, + (unsigned long long)lo, + (unsigned long long)hi); + resync_info_update(mddev, lo, hi); + cmsg.type = cpu_to_le32(type); + cmsg.slot = cpu_to_le32(slot); + cmsg.low = cpu_to_le64(lo); + cmsg.high = cpu_to_le64(hi); + return sendmsg(cinfo, &cmsg); +} + +static int resync_start(struct mddev *mddev, sector_t lo, sector_t hi) +{ + pr_info("%s:%d\n", __func__, __LINE__); + return resync_send(mddev, RESYNCING, lo, hi); +} + +static void resync_finish(struct mddev *mddev) +{ + pr_info("%s:%d\n", __func__, __LINE__); + resync_send(mddev, RESYNCING, 0, 0); +} + +static int area_resyncing(struct mddev *mddev, sector_t lo, sector_t hi) +{ + struct md_cluster_info *cinfo = mddev->cluster_info; + int ret = 0; + struct suspend_info *s; + + 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; +} + +static int add_new_disk_start(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 = rdev->desc_nr; + lock_comm(cinfo); + ret = __sendmsg(cinfo, &cmsg); + if (ret) + 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; + else + dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR); + return ret; +} + +static int add_new_disk_finish(struct mddev *mddev) +{ + struct cluster_msg cmsg; + struct md_cluster_info *cinfo = mddev->cluster_info; + int ret; + /* Write sb and inform others */ + md_update_sb(mddev, 1); + cmsg.type = METADATA_UPDATED; + ret = __sendmsg(cinfo, &cmsg); + unlock_comm(cinfo); + return ret; +} + +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; + struct md_cluster_info *cinfo = mddev->cluster_info; + cmsg.type = REMOVE; + cmsg.raid_slot = rdev->desc_nr; + return __sendmsg(cinfo, &cmsg); +} + +static int gather_bitmaps(struct md_rdev *rdev) +{ + int sn, err; + sector_t lo, hi; + struct cluster_msg cmsg; + struct mddev *mddev = rdev->mddev; + struct md_cluster_info *cinfo = mddev->cluster_info; + + cmsg.type = RE_ADD; + cmsg.raid_slot = rdev->desc_nr; + err = sendmsg(cinfo, &cmsg); + if (err) + goto out; + + for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) { + if (sn == (cinfo->slot_number - 1)) + continue; + err = 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_info_update = resync_info_update, + .resync_start = resync_start, + .resync_finish = resync_finish, + .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_start = add_new_disk_start, + .add_new_disk_finish = add_new_disk_finish, + .new_disk_ack = new_disk_ack, + .remove_disk = remove_disk, + .gather_bitmaps = gather_bitmaps, +}; + +static int __init cluster_init(void) +{ + pr_warn("md-cluster: EXPERIMENTAL. Use with caution\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_LICENSE("GPL"); +MODULE_DESCRIPTION("Clustering support for MD"); |