- 根目录:
- drivers
- md
- md-cluster.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/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. */
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
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 *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;
unsigned long state;
};
enum msg_type {
METADATA_UPDATED = 0,
RESYNCING,
NEWDISK,
REMOVE,
RE_ADD,
BITMAP_NEEDS_SYNC,
};
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;
complete(&res->completion);
}
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_for_completion(&res->completion);
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);
}
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_completion(&res->completion);
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;
if (!res)
return;
/* cancel a lock request or a conversion request that is blocked */
res->flags |= DLM_LKF_CANCEL;
retry:
ret = dlm_unlock(res->ls, res->lksb.sb_lkid, 0, &res->lksb, res);
if (unlikely(ret != 0)) {
pr_info("%s: failed to unlock %s return %d\n", __func__, res->name, ret);
/* if a lock conversion is cancelled, then the lock is put
* back to grant queue, need to ensure it is unlocked */
if (ret == -DLM_ECANCEL)
goto retry;
}
res->flags &= ~DLM_LKF_CANCEL;
wait_for_completion(&res->completion);
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(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)
{
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)
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) {
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;
}
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)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
md_reload_sb(mddev, le32_to_cpu(msg->raid_slot));
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,
le32_to_cpu(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__, le32_to_cpu(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,
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));
}
static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
{
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;
switch (le32_to_cpu(msg->type)) {
case METADATA_UPDATED:
process_metadata_update(mddev, msg);
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:
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;
int ret;
/*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*/
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);
/*release CR on message_lockres*/
ret = dlm_unlock_sync(message_lockres);
if (unlikely(ret != 0))
pr_info("unlock msg failed return %d\n", ret);
}
/* lock_comm()
* Takes the lock on the TOKEN lock resource so no other
* node can communicate while the operation is underway.
* If called again, and the TOKEN lock is alread in EX mode
* return success. However, care must be taken that unlock_comm()
* is called only once.
*/
static int lock_comm(struct md_cluster_info *cinfo)
{
int error;
if (cinfo->token_lockres->mode == DLM_LOCK_EX)
return 0;
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)
{
WARN_ON(cinfo->token_lockres->mode != DLM_LOCK_EX);
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 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)
{
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];
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))
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) {
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);
}
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];
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);
mddev->cluster_info = cinfo;
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->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;
}
cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
if (!cinfo->resync_lockres)
goto err;
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->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 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);
if (err)
pr_err("%s:%d: failed to send BITMAP_NEEDS_SYNC message (%d)\n",
__func__, __LINE__, err);
}
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);
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->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 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;
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");
unlock_comm(cinfo);
return ret;
}
static void metadata_update_cancel(struct mddev *mddev)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
unlock_comm(cinfo);
}
static int resync_start(struct mddev *mddev)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
cinfo->resync_lockres->flags |= DLM_LKF_NOQUEUE;
return dlm_lock_sync(cinfo->resync_lockres, DLM_LOCK_EX);
}
static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
struct cluster_msg cmsg = {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);
return sendmsg(cinfo, &cmsg);
}
static int resync_finish(struct mddev *mddev)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
cinfo->resync_lockres->flags &= ~DLM_LKF_NOQUEUE;
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);
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;
if (ret)
unlock_comm(cinfo);
else
dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
return ret;
}
static void add_new_disk_cancel(struct mddev *mddev)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
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);
}
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);
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,
.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_AUTHOR("SUSE");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Clustering support for MD");