WSL2-Linux-Kernel/drivers/md/md-cluster.c

1497 строки
41 KiB
C

/*
* 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 "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;
/* 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_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 = 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;
}
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) {
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;
spin_lock_irq(&cinfo->suspend_lock);
__remove_suspend_info(cinfo, slot);
spin_unlock_irq(&cinfo->suspend_lock);
mddev->pers->quiesce(mddev, 2);
}
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) {
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 */
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);
mddev->pers->quiesce(mddev, 0);
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, 2);
}
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:
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 = 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
*/
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);
bitmap_free(bitmap);
return -1;
}
bm_lockres->flags |= DLM_LKF_NOQUEUE;
rv = dlm_lock_sync(bm_lockres, DLM_LOCK_PW);
if (!rv)
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);
bitmap_free(bitmap);
return -1;
}
kunmap_atomic(sb);
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;
dlm_unlock_sync(cinfo->resync_lockres);
return resync_info_update(mddev, 0, 0);
}
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 = kzalloc((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 = 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: 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_AUTHOR("SUSE");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Clustering support for MD");