linux/fs/dlm/recoverd.c
Alexander Aring aee742c992 fs: dlm: fix return -EINTR on recovery stopped
This patch will return -EINTR instead of 1 if recovery is stopped. In
case of ping_members() the return value will be checked if the error is
-EINTR for signaling another recovery was triggered and the whole
recovery process will come to a clean end to process the next one.
Returning 1 will abort the recovery process and can leave the recovery
in a broken state.

It was reported with the following kernel log message attached and a gfs2
mount stopped working:

"dlm: bobvirt1: dlm_recover_members error 1"

whereas 1 was returned because of a conversion of "dlm_recovery_stopped()"
to an errno was missing which this patch will introduce. While on it all
other possible missing errno conversions at other places were added as
they are done as in other places.

It might be worth to check the error case at this recovery level,
because some of the functionality also returns -ENOBUFS and check why
recovery ends in a broken state. However this will fix the issue if
another recovery was triggered at some points of recovery handling.

Reported-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-08-19 11:33:03 -05:00

355 lines
8.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/******************************************************************************
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
** Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
**
**
*******************************************************************************
******************************************************************************/
#include "dlm_internal.h"
#include "lockspace.h"
#include "member.h"
#include "dir.h"
#include "ast.h"
#include "recover.h"
#include "lowcomms.h"
#include "lock.h"
#include "requestqueue.h"
#include "recoverd.h"
/* If the start for which we're re-enabling locking (seq) has been superseded
by a newer stop (ls_recover_seq), we need to leave locking disabled.
We suspend dlm_recv threads here to avoid the race where dlm_recv a) sees
locking stopped and b) adds a message to the requestqueue, but dlm_recoverd
enables locking and clears the requestqueue between a and b. */
static int enable_locking(struct dlm_ls *ls, uint64_t seq)
{
int error = -EINTR;
down_write(&ls->ls_recv_active);
spin_lock(&ls->ls_recover_lock);
if (ls->ls_recover_seq == seq) {
set_bit(LSFL_RUNNING, &ls->ls_flags);
/* unblocks processes waiting to enter the dlm */
up_write(&ls->ls_in_recovery);
clear_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
error = 0;
}
spin_unlock(&ls->ls_recover_lock);
up_write(&ls->ls_recv_active);
return error;
}
static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv)
{
unsigned long start;
int error, neg = 0;
log_rinfo(ls, "dlm_recover %llu", (unsigned long long)rv->seq);
mutex_lock(&ls->ls_recoverd_active);
dlm_callback_suspend(ls);
dlm_clear_toss(ls);
/*
* This list of root rsb's will be the basis of most of the recovery
* routines.
*/
dlm_create_root_list(ls);
/*
* Add or remove nodes from the lockspace's ls_nodes list.
*/
error = dlm_recover_members(ls, rv, &neg);
if (error) {
log_rinfo(ls, "dlm_recover_members error %d", error);
goto fail;
}
dlm_recover_dir_nodeid(ls);
ls->ls_recover_dir_sent_res = 0;
ls->ls_recover_dir_sent_msg = 0;
ls->ls_recover_locks_in = 0;
dlm_set_recover_status(ls, DLM_RS_NODES);
error = dlm_recover_members_wait(ls);
if (error) {
log_rinfo(ls, "dlm_recover_members_wait error %d", error);
goto fail;
}
start = jiffies;
/*
* Rebuild our own share of the directory by collecting from all other
* nodes their master rsb names that hash to us.
*/
error = dlm_recover_directory(ls);
if (error) {
log_rinfo(ls, "dlm_recover_directory error %d", error);
goto fail;
}
dlm_set_recover_status(ls, DLM_RS_DIR);
error = dlm_recover_directory_wait(ls);
if (error) {
log_rinfo(ls, "dlm_recover_directory_wait error %d", error);
goto fail;
}
log_rinfo(ls, "dlm_recover_directory %u out %u messages",
ls->ls_recover_dir_sent_res, ls->ls_recover_dir_sent_msg);
/*
* We may have outstanding operations that are waiting for a reply from
* a failed node. Mark these to be resent after recovery. Unlock and
* cancel ops can just be completed.
*/
dlm_recover_waiters_pre(ls);
error = dlm_recovery_stopped(ls);
if (error) {
error = -EINTR;
goto fail;
}
if (neg || dlm_no_directory(ls)) {
/*
* Clear lkb's for departed nodes.
*/
dlm_recover_purge(ls);
/*
* Get new master nodeid's for rsb's that were mastered on
* departed nodes.
*/
error = dlm_recover_masters(ls);
if (error) {
log_rinfo(ls, "dlm_recover_masters error %d", error);
goto fail;
}
/*
* Send our locks on remastered rsb's to the new masters.
*/
error = dlm_recover_locks(ls);
if (error) {
log_rinfo(ls, "dlm_recover_locks error %d", error);
goto fail;
}
dlm_set_recover_status(ls, DLM_RS_LOCKS);
error = dlm_recover_locks_wait(ls);
if (error) {
log_rinfo(ls, "dlm_recover_locks_wait error %d", error);
goto fail;
}
log_rinfo(ls, "dlm_recover_locks %u in",
ls->ls_recover_locks_in);
/*
* Finalize state in master rsb's now that all locks can be
* checked. This includes conversion resolution and lvb
* settings.
*/
dlm_recover_rsbs(ls);
} else {
/*
* Other lockspace members may be going through the "neg" steps
* while also adding us to the lockspace, in which case they'll
* be doing the recover_locks (RS_LOCKS) barrier.
*/
dlm_set_recover_status(ls, DLM_RS_LOCKS);
error = dlm_recover_locks_wait(ls);
if (error) {
log_rinfo(ls, "dlm_recover_locks_wait error %d", error);
goto fail;
}
}
dlm_release_root_list(ls);
/*
* Purge directory-related requests that are saved in requestqueue.
* All dir requests from before recovery are invalid now due to the dir
* rebuild and will be resent by the requesting nodes.
*/
dlm_purge_requestqueue(ls);
dlm_set_recover_status(ls, DLM_RS_DONE);
error = dlm_recover_done_wait(ls);
if (error) {
log_rinfo(ls, "dlm_recover_done_wait error %d", error);
goto fail;
}
dlm_clear_members_gone(ls);
dlm_adjust_timeouts(ls);
dlm_callback_resume(ls);
error = enable_locking(ls, rv->seq);
if (error) {
log_rinfo(ls, "enable_locking error %d", error);
goto fail;
}
error = dlm_process_requestqueue(ls);
if (error) {
log_rinfo(ls, "dlm_process_requestqueue error %d", error);
goto fail;
}
error = dlm_recover_waiters_post(ls);
if (error) {
log_rinfo(ls, "dlm_recover_waiters_post error %d", error);
goto fail;
}
dlm_recover_grant(ls);
log_rinfo(ls, "dlm_recover %llu generation %u done: %u ms",
(unsigned long long)rv->seq, ls->ls_generation,
jiffies_to_msecs(jiffies - start));
mutex_unlock(&ls->ls_recoverd_active);
dlm_lsop_recover_done(ls);
return 0;
fail:
dlm_release_root_list(ls);
log_rinfo(ls, "dlm_recover %llu error %d",
(unsigned long long)rv->seq, error);
mutex_unlock(&ls->ls_recoverd_active);
return error;
}
/* The dlm_ls_start() that created the rv we take here may already have been
stopped via dlm_ls_stop(); in that case we need to leave the RECOVERY_STOP
flag set. */
static void do_ls_recovery(struct dlm_ls *ls)
{
struct dlm_recover *rv = NULL;
spin_lock(&ls->ls_recover_lock);
rv = ls->ls_recover_args;
ls->ls_recover_args = NULL;
if (rv && ls->ls_recover_seq == rv->seq)
clear_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
spin_unlock(&ls->ls_recover_lock);
if (rv) {
ls_recover(ls, rv);
kfree(rv->nodes);
kfree(rv);
}
}
static int dlm_recoverd(void *arg)
{
struct dlm_ls *ls;
ls = dlm_find_lockspace_local(arg);
if (!ls) {
log_print("dlm_recoverd: no lockspace %p", arg);
return -1;
}
down_write(&ls->ls_in_recovery);
set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
wake_up(&ls->ls_recover_lock_wait);
while (1) {
/*
* We call kthread_should_stop() after set_current_state().
* This is because it works correctly if kthread_stop() is
* called just before set_current_state().
*/
set_current_state(TASK_INTERRUPTIBLE);
if (kthread_should_stop()) {
set_current_state(TASK_RUNNING);
break;
}
if (!test_bit(LSFL_RECOVER_WORK, &ls->ls_flags) &&
!test_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) {
if (kthread_should_stop())
break;
schedule();
}
set_current_state(TASK_RUNNING);
if (test_and_clear_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) {
down_write(&ls->ls_in_recovery);
set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
wake_up(&ls->ls_recover_lock_wait);
}
if (test_and_clear_bit(LSFL_RECOVER_WORK, &ls->ls_flags))
do_ls_recovery(ls);
}
if (test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags))
up_write(&ls->ls_in_recovery);
dlm_put_lockspace(ls);
return 0;
}
int dlm_recoverd_start(struct dlm_ls *ls)
{
struct task_struct *p;
int error = 0;
p = kthread_run(dlm_recoverd, ls, "dlm_recoverd");
if (IS_ERR(p))
error = PTR_ERR(p);
else
ls->ls_recoverd_task = p;
return error;
}
void dlm_recoverd_stop(struct dlm_ls *ls)
{
kthread_stop(ls->ls_recoverd_task);
}
void dlm_recoverd_suspend(struct dlm_ls *ls)
{
wake_up(&ls->ls_wait_general);
mutex_lock(&ls->ls_recoverd_active);
}
void dlm_recoverd_resume(struct dlm_ls *ls)
{
mutex_unlock(&ls->ls_recoverd_active);
}