ocfs2/dlm: Do not purge lockres that is being migrated dlm_purge_lockres()
This patch attempts to fix a fine race between purging and migration.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c
index 4060bb3..d490b66 100644
--- a/fs/ocfs2/dlm/dlmthread.c
+++ b/fs/ocfs2/dlm/dlmthread.c
@@ -162,12 +162,28 @@
spin_lock(&res->spinlock);
if (!__dlm_lockres_unused(res)) {
- spin_unlock(&res->spinlock);
mlog(0, "%s:%.*s: tried to purge but not unused\n",
dlm->name, res->lockname.len, res->lockname.name);
- return -ENOTEMPTY;
+ __dlm_print_one_lock_resource(res);
+ spin_unlock(&res->spinlock);
+ BUG();
}
+
+ if (res->state & DLM_LOCK_RES_MIGRATING) {
+ mlog(0, "%s:%.*s: Delay dropref as this lockres is "
+ "being remastered\n", dlm->name, res->lockname.len,
+ res->lockname.name);
+ /* Re-add the lockres to the end of the purge list */
+ if (!list_empty(&res->purge)) {
+ list_del_init(&res->purge);
+ list_add_tail(&res->purge, &dlm->purge_list);
+ }
+ spin_unlock(&res->spinlock);
+ return 0;
+ }
+
master = (res->owner == dlm->node_num);
+
if (!master)
res->state |= DLM_LOCK_RES_DROPPING_REF;
spin_unlock(&res->spinlock);