[PATCH 3.16 115/366] ocfs2/dlm: wait for dlm recovery done when migrating all lock resources

Ben Hutchings
2018-10-14T23:38:42Z

From: piaojun <piaojun@huawei.com>

commit 60c7ec9ee4a3410c2cb08850102d363c7e207f48 upstream.

Wait for dlm recovery done when migrating all lock resources in case that
new lock resource left after leaving dlm domain. And the left lock
resource will cause other nodes BUG.

NodeA NodeB NodeC

umount:
dlm_unregister_domain()
dlm_migrate_all_locks()

NodeB down

do recovery for NodeB
and collect a new lockres
form other live nodes:

dlm_do_recovery
dlm_remaster_locks
dlm_request_all_locks:

dlm_mig_lockres_handler
dlm_new_lockres
__dlm_insert_lockres

at last NodeA become the
master of the new lockres
and leave domain:
dlm_leave_domain()

mount:
dlm_join_domain()

touch file and request
for the owner of the new
lockres, but all the
other nodes said 'NO',
so NodeC decide to be
the owner, and send do
assert msg to other
nodes:
dlmlock()
dlm_get_lock_resource()
dlm_do_assert_master()

other nodes receive the msg
and found two masters exist.
at last cause BUG in
dlm_assert_master_handler()
-->BUG();

Link: http://lkml.kernel.org/r/5AAA6E25.7090303@huawei.com
Fixes: bc9838c4d44a ("dlm: allow dlm do recovery during shutdown")
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/ocfs2/dlm/dlmcommon.h | 1 +
fs/ocfs2/dlm/dlmdomain.c | 15 +++++++++++++++
fs/ocfs2/dlm/dlmrecovery.c | 13 ++++++++++---
3 files changed, 26 insertions(+), 3 deletions(-)

--- a/fs/ocfs2/dlm/dlmcommon.h
+++ b/fs/ocfs2/dlm/dlmcommon.h
@@ -140,6 +140,7 @@ struct dlm_ctxt
u8 node_num;
u32 key;
u8 joining_node;
+ u8 migrate_done; /* set to 1 means node has migrated all lock resources */
wait_queue_head_t dlm_join_events;
unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -460,6 +460,19 @@ redo_bucket:
cond_resched_lock(&dlm->spinlock);
num += n;
}
+
+ if (!num) {
+ if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
+ mlog(0, "%s: perhaps there are more lock resources "
+ "need to be migrated after dlm recovery\n", dlm->name);
+ ret = -EAGAIN;
+ } else {
+ mlog(0, "%s: we won't do dlm recovery after migrating "
+ "all lock resources\n", dlm->name);
+ dlm->migrate_done = 1;
+ }
+ }
+
spin_unlock(&dlm->spinlock);
wake_up(&dlm->dlm_thread_wq);

@@ -2063,6 +2076,8 @@ static struct dlm_ctxt *dlm_alloc_ctxt(c
dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
init_waitqueue_head(&dlm->dlm_join_events);

+ dlm->migrate_done = 0;
+
dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;

--- a/fs/ocfs2/dlm/dlmrecovery.c
+++ b/fs/ocfs2/dlm/dlmrecovery.c
@@ -423,12 +423,11 @@ void dlm_wait_for_recovery(struct dlm_ct

static void dlm_begin_recovery(struct dlm_ctxt *dlm)
{
- spin_lock(&dlm->spinlock);
+ assert_spin_locked(&dlm->spinlock);
BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
printk(KERN_NOTICE "o2dlm: Begin recovery on domain %s for node %u\n",
dlm->name, dlm->reco.dead_node);
dlm->reco.state |= DLM_RECO_STATE_ACTIVE;
- spin_unlock(&dlm->spinlock);
}

static void dlm_end_recovery(struct dlm_ctxt *dlm)
@@ -456,6 +455,13 @@ static int dlm_do_recovery(struct dlm_ct

spin_lock(&dlm->spinlock);

+ if (dlm->migrate_done) {
+ mlog(0, "%s: no need do recovery after migrating all "
+ "lock resources\n", dlm->name);
+ spin_unlock(&dlm->spinlock);
+ return 0;
+ }
+
/* check to see if the new master has died */
if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
test_bit(dlm->reco.new_master, dlm->recovery_map)) {
@@ -490,12 +496,13 @@ static int dlm_do_recovery(struct dlm_ct
mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
dlm->reco.dead_node);
- spin_unlock(&dlm->spinlock);

/* take write barrier */
/* (stops the list reshuffling thread, proxy ast handling) */
dlm_begin_recovery(dlm);

+ spin_unlock(&dlm->spinlock);
+
if (dlm->reco.new_master == dlm->node_num)
goto master_here;