/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- dlm_wait_timer_fn
- dlm_wait_function
- dlm_recover_status
- dlm_set_recover_status
- wait_status_all
- wait_status_low
- wait_status
- dlm_recover_members_wait
- dlm_recover_directory_wait
- dlm_recover_locks_wait
- dlm_recover_done_wait
- recover_list_empty
- recover_list_add
- recover_list_del
- recover_list_find
- recover_list_clear
- set_lock_master
- set_master_lkbs
- set_new_master
- recover_master
- recover_master_static
- dlm_recover_masters
- dlm_recover_master_reply
- recover_locks_queue
- recover_locks
- dlm_recover_locks
- dlm_recovered_lock
- recover_lvb
- recover_conversion
- set_locks_purged
- dlm_recover_rsbs
- dlm_create_root_list
- dlm_release_root_list
- dlm_clear_toss_list
/******************************************************************************
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
**
** This copyrighted material is made available to anyone wishing to use,
** modify, copy, or redistribute it subject to the terms and conditions
** of the GNU General Public License v.2.
**
*******************************************************************************
******************************************************************************/
#include "dlm_internal.h"
#include "lockspace.h"
#include "dir.h"
#include "config.h"
#include "ast.h"
#include "memory.h"
#include "rcom.h"
#include "lock.h"
#include "lowcomms.h"
#include "member.h"
#include "recover.h"
/*
* Recovery waiting routines: these functions wait for a particular reply from
* a remote node, or for the remote node to report a certain status. They need
* to abort if the lockspace is stopped indicating a node has failed (perhaps
* the one being waited for).
*/
/*
* Wait until given function returns non-zero or lockspace is stopped
* (LS_RECOVERY_STOP set due to failure of a node in ls_nodes). When another
* function thinks it could have completed the waited-on task, they should wake
* up ls_wait_general to get an immediate response rather than waiting for the
* timer to detect the result. A timer wakes us up periodically while waiting
* to see if we should abort due to a node failure. This should only be called
* by the dlm_recoverd thread.
*/
static void dlm_wait_timer_fn(unsigned long data)
{
struct dlm_ls *ls = (struct dlm_ls *) data;
mod_timer(&ls->ls_timer, jiffies + (dlm_config.ci_recover_timer * HZ));
wake_up(&ls->ls_wait_general);
}
int dlm_wait_function(struct dlm_ls *ls, int (*testfn) (struct dlm_ls *ls))
{
int error = 0;
init_timer(&ls->ls_timer);
ls->ls_timer.function = dlm_wait_timer_fn;
ls->ls_timer.data = (long) ls;
ls->ls_timer.expires = jiffies + (dlm_config.ci_recover_timer * HZ);
add_timer(&ls->ls_timer);
wait_event(ls->ls_wait_general, testfn(ls) || dlm_recovery_stopped(ls));
del_timer_sync(&ls->ls_timer);
if (dlm_recovery_stopped(ls)) {
log_debug(ls, "dlm_wait_function aborted");
error = -EINTR;
}
return error;
}
/*
* An efficient way for all nodes to wait for all others to have a certain
* status. The node with the lowest nodeid polls all the others for their
* status (wait_status_all) and all the others poll the node with the low id
* for its accumulated result (wait_status_low). When all nodes have set
* status flag X, then status flag X_ALL will be set on the low nodeid.
*/
uint32_t dlm_recover_status(struct dlm_ls *ls)
{
uint32_t status;
spin_lock(&ls->ls_recover_lock);
status = ls->ls_recover_status;
spin_unlock(&ls->ls_recover_lock);
return status;
}
void dlm_set_recover_status(struct dlm_ls *ls, uint32_t status)
{
spin_lock(&ls->ls_recover_lock);
ls->ls_recover_status |= status;
spin_unlock(&ls->ls_recover_lock);
}
static int wait_status_all(struct dlm_ls *ls, uint32_t wait_status)
{
struct dlm_rcom *rc = ls->ls_recover_buf;
struct dlm_member *memb;
int error = 0, delay;
list_for_each_entry(memb, &ls->ls_nodes, list) {
delay = 0;
for (;;) {
if (dlm_recovery_stopped(ls)) {
error = -EINTR;
goto out;
}
error = dlm_rcom_status(ls, memb->nodeid);
if (error)
goto out;
if (rc->rc_result & wait_status)
break;
if (delay < 1000)
delay += 20;
msleep(delay);
}
}
out:
return error;
}
static int wait_status_low(struct dlm_ls *ls, uint32_t wait_status)
{
struct dlm_rcom *rc = ls->ls_recover_buf;
int error = 0, delay = 0, nodeid = ls->ls_low_nodeid;
for (;;) {
if (dlm_recovery_stopped(ls)) {
error = -EINTR;
goto out;
}
error = dlm_rcom_status(ls, nodeid);
if (error)
break;
if (rc->rc_result & wait_status)
break;
if (delay < 1000)
delay += 20;
msleep(delay);
}
out:
return error;
}
static int wait_status(struct dlm_ls *ls, uint32_t status)
{
uint32_t status_all = status << 1;
int error;
if (ls->ls_low_nodeid == dlm_our_nodeid()) {
error = wait_status_all(ls, status);
if (!error)
dlm_set_recover_status(ls, status_all);
} else
error = wait_status_low(ls, status_all);
return error;
}
int dlm_recover_members_wait(struct dlm_ls *ls)
{
return wait_status(ls, DLM_RS_NODES);
}
int dlm_recover_directory_wait(struct dlm_ls *ls)
{
return wait_status(ls, DLM_RS_DIR);
}
int dlm_recover_locks_wait(struct dlm_ls *ls)
{
return wait_status(ls, DLM_RS_LOCKS);
}
int dlm_recover_done_wait(struct dlm_ls *ls)
{
return wait_status(ls, DLM_RS_DONE);
}
/*
* The recover_list contains all the rsb's for which we've requested the new
* master nodeid. As replies are returned from the resource directories the
* rsb's are removed from the list. When the list is empty we're done.
*
* The recover_list is later similarly used for all rsb's for which we've sent
* new lkb's and need to receive new corresponding lkid's.
*
* We use the address of the rsb struct as a simple local identifier for the
* rsb so we can match an rcom reply with the rsb it was sent for.
*/
static int recover_list_empty(struct dlm_ls *ls)
{
int empty;
spin_lock(&ls->ls_recover_list_lock);
empty = list_empty(&ls->ls_recover_list);
spin_unlock(&ls->ls_recover_list_lock);
return empty;
}
static void recover_list_add(struct dlm_rsb *r)
{
struct dlm_ls *ls = r->res_ls;
spin_lock(&ls->ls_recover_list_lock);
if (list_empty(&r->res_recover_list)) {
list_add_tail(&r->res_recover_list, &ls->ls_recover_list);
ls->ls_recover_list_count++;
dlm_hold_rsb(r);
}
spin_unlock(&ls->ls_recover_list_lock);
}
static void recover_list_del(struct dlm_rsb *r)
{
struct dlm_ls *ls = r->res_ls;
spin_lock(&ls->ls_recover_list_lock);
list_del_init(&r->res_recover_list);
ls->ls_recover_list_count--;
spin_unlock(&ls->ls_recover_list_lock);
dlm_put_rsb(r);
}
static struct dlm_rsb *recover_list_find(struct dlm_ls *ls, uint64_t id)
{
struct dlm_rsb *r = NULL;
spin_lock(&ls->ls_recover_list_lock);
list_for_each_entry(r, &ls->ls_recover_list, res_recover_list) {
if (id == (unsigned long) r)
goto out;
}
r = NULL;
out:
spin_unlock(&ls->ls_recover_list_lock);
return r;
}
static void recover_list_clear(struct dlm_ls *ls)
{
struct dlm_rsb *r, *s;
spin_lock(&ls->ls_recover_list_lock);
list_for_each_entry_safe(r, s, &ls->ls_recover_list, res_recover_list) {
list_del_init(&r->res_recover_list);
r->res_recover_locks_count = 0;
dlm_put_rsb(r);
ls->ls_recover_list_count--;
}
if (ls->ls_recover_list_count != 0) {
log_error(ls, "warning: recover_list_count %d",
ls->ls_recover_list_count);
ls->ls_recover_list_count = 0;
}
spin_unlock(&ls->ls_recover_list_lock);
}
/* Master recovery: find new master node for rsb's that were
mastered on nodes that have been removed.
dlm_recover_masters
recover_master
dlm_send_rcom_lookup -> receive_rcom_lookup
dlm_dir_lookup
receive_rcom_lookup_reply <-
dlm_recover_master_reply
set_new_master
set_master_lkbs
set_lock_master
*/
/*
* Set the lock master for all LKBs in a lock queue
* If we are the new master of the rsb, we may have received new
* MSTCPY locks from other nodes already which we need to ignore
* when setting the new nodeid.
*/
static void set_lock_master(struct list_head *queue, int nodeid)
{
struct dlm_lkb *lkb;
list_for_each_entry(lkb, queue, lkb_statequeue)
if (!(lkb->lkb_flags & DLM_IFL_MSTCPY))
lkb->lkb_nodeid = nodeid;
}
static void set_master_lkbs(struct dlm_rsb *r)
{
set_lock_master(&r->res_grantqueue, r->res_nodeid);
set_lock_master(&r->res_convertqueue, r->res_nodeid);
set_lock_master(&r->res_waitqueue, r->res_nodeid);
}
/*
* Propogate the new master nodeid to locks
* The NEW_MASTER flag tells dlm_recover_locks() which rsb's to consider.
* The NEW_MASTER2 flag tells recover_lvb() and set_locks_purged() which
* rsb's to consider.
*/
static void set_new_master(struct dlm_rsb *r, int nodeid)
{
lock_rsb(r);
r->res_nodeid = nodeid;
set_master_lkbs(r);
rsb_set_flag(r, RSB_NEW_MASTER);
rsb_set_flag(r, RSB_NEW_MASTER2);
unlock_rsb(r);
}
/*
* We do async lookups on rsb's that need new masters. The rsb's
* waiting for a lookup reply are kept on the recover_list.
*/
static int recover_master(struct dlm_rsb *r)
{
struct dlm_ls *ls = r->res_ls;
int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
dir_nodeid = dlm_dir_nodeid(r);
if (dir_nodeid == our_nodeid) {
error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
r->res_length, &ret_nodeid);
if (error)
log_error(ls, "recover dir lookup error %d", error);
if (ret_nodeid == our_nodeid)
ret_nodeid = 0;
set_new_master(r, ret_nodeid);
} else {
recover_list_add(r);
error = dlm_send_rcom_lookup(r, dir_nodeid);
}
return error;
}
/*
* When not using a directory, most resource names will hash to a new static
* master nodeid and the resource will need to be remastered.
*/
static int recover_master_static(struct dlm_rsb *r)
{
int master = dlm_dir_nodeid(r);
if (master == dlm_our_nodeid())
master = 0;
if (r->res_nodeid != master) {
if (is_master(r))
dlm_purge_mstcpy_locks(r);
set_new_master(r, master);
return 1;
}
return 0;
}
/*
* Go through local root resources and for each rsb which has a master which
* has departed, get the new master nodeid from the directory. The dir will
* assign mastery to the first node to look up the new master. That means
* we'll discover in this lookup if we're the new master of any rsb's.
*
* We fire off all the dir lookup requests individually and asynchronously to
* the correct dir node.
*/
int dlm_recover_masters(struct dlm_ls *ls)
{
struct dlm_rsb *r;
int error = 0, count = 0;
log_debug(ls, "dlm_recover_masters");
down_read(&ls->ls_root_sem);
list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
if (dlm_recovery_stopped(ls)) {
up_read(&ls->ls_root_sem);
error = -EINTR;
goto out;
}
if (dlm_no_directory(ls))
count += recover_master_static(r);
else if (!is_master(r) &&
(dlm_is_removed(ls, r->res_nodeid) ||
rsb_flag(r, RSB_NEW_MASTER))) {
recover_master(r);
count++;
}
schedule();
}
up_read(&ls->ls_root_sem);
log_debug(ls, "dlm_recover_masters %d resources", count);
error = dlm_wait_function(ls, &recover_list_empty);
out:
if (error)
recover_list_clear(ls);
return error;
}
int dlm_recover_master_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
{
struct dlm_rsb *r;
int nodeid;
r = recover_list_find(ls, rc->rc_id);
if (!r) {
log_error(ls, "dlm_recover_master_reply no id %llx",
(unsigned long long)rc->rc_id);
goto out;
}
nodeid = rc->rc_result;
if (nodeid == dlm_our_nodeid())
nodeid = 0;
set_new_master(r, nodeid);
recover_list_del(r);
if (recover_list_empty(ls))
wake_up(&ls->ls_wait_general);
out:
return 0;
}
/* Lock recovery: rebuild the process-copy locks we hold on a
remastered rsb on the new rsb master.
dlm_recover_locks
recover_locks
recover_locks_queue
dlm_send_rcom_lock -> receive_rcom_lock
dlm_recover_master_copy
receive_rcom_lock_reply <-
dlm_recover_process_copy
*/
/*
* keep a count of the number of lkb's we send to the new master; when we get
* an equal number of replies then recovery for the rsb is done
*/
static int recover_locks_queue(struct dlm_rsb *r, struct list_head *head)
{
struct dlm_lkb *lkb;
int error = 0;
list_for_each_entry(lkb, head, lkb_statequeue) {
error = dlm_send_rcom_lock(r, lkb);
if (error)
break;
r->res_recover_locks_count++;
}
return error;
}
static int recover_locks(struct dlm_rsb *r)
{
int error = 0;
lock_rsb(r);
DLM_ASSERT(!r->res_recover_locks_count, dlm_dump_rsb(r););
error = recover_locks_queue(r, &r->res_grantqueue);
if (error)
goto out;
error = recover_locks_queue(r, &r->res_convertqueue);
if (error)
goto out;
error = recover_locks_queue(r, &r->res_waitqueue);
if (error)
goto out;
if (r->res_recover_locks_count)
recover_list_add(r);
else
rsb_clear_flag(r, RSB_NEW_MASTER);
out:
unlock_rsb(r);
return error;
}
int dlm_recover_locks(struct dlm_ls *ls)
{
struct dlm_rsb *r;
int error, count = 0;
log_debug(ls, "dlm_recover_locks");
down_read(&ls->ls_root_sem);
list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
if (is_master(r)) {
rsb_clear_flag(r, RSB_NEW_MASTER);
continue;
}
if (!rsb_flag(r, RSB_NEW_MASTER))
continue;
if (dlm_recovery_stopped(ls)) {
error = -EINTR;
up_read(&ls->ls_root_sem);
goto out;
}
error = recover_locks(r);
if (error) {
up_read(&ls->ls_root_sem);
goto out;
}
count += r->res_recover_locks_count;
}
up_read(&ls->ls_root_sem);
log_debug(ls, "dlm_recover_locks %d locks", count);
error = dlm_wait_function(ls, &recover_list_empty);
out:
if (error)
recover_list_clear(ls);
else
dlm_set_recover_status(ls, DLM_RS_LOCKS);
return error;
}
void dlm_recovered_lock(struct dlm_rsb *r)
{
DLM_ASSERT(rsb_flag(r, RSB_NEW_MASTER), dlm_dump_rsb(r););
r->res_recover_locks_count--;
if (!r->res_recover_locks_count) {
rsb_clear_flag(r, RSB_NEW_MASTER);
recover_list_del(r);
}
if (recover_list_empty(r->res_ls))
wake_up(&r->res_ls->ls_wait_general);
}
/*
* The lvb needs to be recovered on all master rsb's. This includes setting
* the VALNOTVALID flag if necessary, and determining the correct lvb contents
* based on the lvb's of the locks held on the rsb.
*
* RSB_VALNOTVALID is set if there are only NL/CR locks on the rsb. If it
* was already set prior to recovery, it's not cleared, regardless of locks.
*
* The LVB contents are only considered for changing when this is a new master
* of the rsb (NEW_MASTER2). Then, the rsb's lvb is taken from any lkb with
* mode > CR. If no lkb's exist with mode above CR, the lvb contents are taken
* from the lkb with the largest lvb sequence number.
*/
static void recover_lvb(struct dlm_rsb *r)
{
struct dlm_lkb *lkb, *high_lkb = NULL;
uint32_t high_seq = 0;
int lock_lvb_exists = 0;
int big_lock_exists = 0;
int lvblen = r->res_ls->ls_lvblen;
list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
continue;
lock_lvb_exists = 1;
if (lkb->lkb_grmode > DLM_LOCK_CR) {
big_lock_exists = 1;
goto setflag;
}
if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
high_lkb = lkb;
high_seq = lkb->lkb_lvbseq;
}
}
list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
continue;
lock_lvb_exists = 1;
if (lkb->lkb_grmode > DLM_LOCK_CR) {
big_lock_exists = 1;
goto setflag;
}
if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
high_lkb = lkb;
high_seq = lkb->lkb_lvbseq;
}
}
setflag:
if (!lock_lvb_exists)
goto out;
if (!big_lock_exists)
rsb_set_flag(r, RSB_VALNOTVALID);
/* don't mess with the lvb unless we're the new master */
if (!rsb_flag(r, RSB_NEW_MASTER2))
goto out;
if (!r->res_lvbptr) {
r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
if (!r->res_lvbptr)
goto out;
}
if (big_lock_exists) {
r->res_lvbseq = lkb->lkb_lvbseq;
memcpy(r->res_lvbptr, lkb->lkb_lvbptr, lvblen);
} else if (high_lkb) {
r->res_lvbseq = high_lkb->lkb_lvbseq;
memcpy(r->res_lvbptr, high_lkb->lkb_lvbptr, lvblen);
} else {
r->res_lvbseq = 0;
memset(r->res_lvbptr, 0, lvblen);
}
out:
return;
}
/* All master rsb's flagged RECOVER_CONVERT need to be looked at. The locks
converting PR->CW or CW->PR need to have their lkb_grmode set. */
static void recover_conversion(struct dlm_rsb *r)
{
struct dlm_lkb *lkb;
int grmode = -1;
list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
if (lkb->lkb_grmode == DLM_LOCK_PR ||
lkb->lkb_grmode == DLM_LOCK_CW) {
grmode = lkb->lkb_grmode;
break;
}
}
list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
if (lkb->lkb_grmode != DLM_LOCK_IV)
continue;
if (grmode == -1)
lkb->lkb_grmode = lkb->lkb_rqmode;
else
lkb->lkb_grmode = grmode;
}
}
/* We've become the new master for this rsb and waiting/converting locks may
need to be granted in dlm_grant_after_purge() due to locks that may have
existed from a removed node. */
static void set_locks_purged(struct dlm_rsb *r)
{
if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
rsb_set_flag(r, RSB_LOCKS_PURGED);
}
void dlm_recover_rsbs(struct dlm_ls *ls)
{
struct dlm_rsb *r;
int count = 0;
log_debug(ls, "dlm_recover_rsbs");
down_read(&ls->ls_root_sem);
list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
lock_rsb(r);
if (is_master(r)) {
if (rsb_flag(r, RSB_RECOVER_CONVERT))
recover_conversion(r);
if (rsb_flag(r, RSB_NEW_MASTER2))
set_locks_purged(r);
recover_lvb(r);
count++;
}
rsb_clear_flag(r, RSB_RECOVER_CONVERT);
rsb_clear_flag(r, RSB_NEW_MASTER2);
unlock_rsb(r);
}
up_read(&ls->ls_root_sem);
log_debug(ls, "dlm_recover_rsbs %d rsbs", count);
}
/* Create a single list of all root rsb's to be used during recovery */
int dlm_create_root_list(struct dlm_ls *ls)
{
struct dlm_rsb *r;
int i, error = 0;
down_write(&ls->ls_root_sem);
if (!list_empty(&ls->ls_root_list)) {
log_error(ls, "root list not empty");
error = -EINVAL;
goto out;
}
for (i = 0; i < ls->ls_rsbtbl_size; i++) {
read_lock(&ls->ls_rsbtbl[i].lock);
list_for_each_entry(r, &ls->ls_rsbtbl[i].list, res_hashchain) {
list_add(&r->res_root_list, &ls->ls_root_list);
dlm_hold_rsb(r);
}
/* If we're using a directory, add tossed rsbs to the root
list; they'll have entries created in the new directory,
but no other recovery steps should do anything with them. */
if (dlm_no_directory(ls)) {
read_unlock(&ls->ls_rsbtbl[i].lock);
continue;
}
list_for_each_entry(r, &ls->ls_rsbtbl[i].toss, res_hashchain) {
list_add(&r->res_root_list, &ls->ls_root_list);
dlm_hold_rsb(r);
}
read_unlock(&ls->ls_rsbtbl[i].lock);
}
out:
up_write(&ls->ls_root_sem);
return error;
}
void dlm_release_root_list(struct dlm_ls *ls)
{
struct dlm_rsb *r, *safe;
down_write(&ls->ls_root_sem);
list_for_each_entry_safe(r, safe, &ls->ls_root_list, res_root_list) {
list_del_init(&r->res_root_list);
dlm_put_rsb(r);
}
up_write(&ls->ls_root_sem);
}
/* If not using a directory, clear the entire toss list, there's no benefit to
caching the master value since it's fixed. If we are using a dir, keep the
rsb's we're the master of. Recovery will add them to the root list and from
there they'll be entered in the rebuilt directory. */
void dlm_clear_toss_list(struct dlm_ls *ls)
{
struct dlm_rsb *r, *safe;
int i;
for (i = 0; i < ls->ls_rsbtbl_size; i++) {
write_lock(&ls->ls_rsbtbl[i].lock);
list_for_each_entry_safe(r, safe, &ls->ls_rsbtbl[i].toss,
res_hashchain) {
if (dlm_no_directory(ls) || !is_master(r)) {
list_del(&r->res_hashchain);
dlm_free_rsb(r);
}
}
write_unlock(&ls->ls_rsbtbl[i].lock);
}
}