diff options
| -rw-r--r-- | fs/ocfs2/dlm/dlmcommon.h | 1 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmrecovery.c | 40 |
2 files changed, 35 insertions, 6 deletions
diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h index 1f939631ab7..dc8ea666efd 100644 --- a/fs/ocfs2/dlm/dlmcommon.h +++ b/fs/ocfs2/dlm/dlmcommon.h @@ -176,6 +176,7 @@ struct dlm_mig_lockres_priv { struct dlm_lock_resource *lockres; u8 real_master; + u8 extra_ref; }; struct dlm_assert_master_priv diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index db17727594a..f9468355242 100644 --- a/fs/ocfs2/dlm/dlmrecovery.c +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -1327,6 +1327,7 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data, (struct dlm_migratable_lockres *)msg->buf; int ret = 0; u8 real_master; + u8 extra_refs = 0; char *buf = NULL; struct dlm_work_item *item = NULL; struct dlm_lock_resource *res = NULL; @@ -1404,16 +1405,28 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data, __dlm_insert_lockres(dlm, res); spin_unlock(&dlm->spinlock); + /* Add an extra ref for this lock-less lockres lest the + * dlm_thread purges it before we get the chance to add + * locks to it */ + dlm_lockres_get(res); + + /* There are three refs that need to be put. + * 1. Taken above. + * 2. kref_init in dlm_new_lockres()->dlm_init_lockres(). + * 3. dlm_lookup_lockres() + * The first one is handled at the end of this function. The + * other two are handled in the worker thread after locks have + * been attached. Yes, we don't wait for purge time to match + * kref_init. The lockres will still have atleast one ref + * added because it is in the hash __dlm_insert_lockres() */ + extra_refs++; + /* now that the new lockres is inserted, * make it usable by other processes */ spin_lock(&res->spinlock); res->state &= ~DLM_LOCK_RES_IN_PROGRESS; spin_unlock(&res->spinlock); wake_up(&res->wq); - - /* add an extra ref for just-allocated lockres - * otherwise the lockres will be purged immediately */ - dlm_lockres_get(res); } /* at this point we have allocated everything we need, @@ -1443,12 +1456,17 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data, dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf); item->u.ml.lockres = res; /* already have a ref */ item->u.ml.real_master = real_master; + item->u.ml.extra_ref = extra_refs; spin_lock(&dlm->work_lock); list_add_tail(&item->list, &dlm->work_list); spin_unlock(&dlm->work_lock); queue_work(dlm->dlm_worker, &dlm->dispatched_work); leave: + /* One extra ref taken needs to be put here */ + if (extra_refs) + dlm_lockres_put(res); + dlm_put(dlm); if (ret < 0) { if (buf) @@ -1464,17 +1482,19 @@ leave: static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data) { - struct dlm_ctxt *dlm = data; + struct dlm_ctxt *dlm; struct dlm_migratable_lockres *mres; int ret = 0; struct dlm_lock_resource *res; u8 real_master; + u8 extra_ref; dlm = item->dlm; mres = (struct dlm_migratable_lockres *)data; res = item->u.ml.lockres; real_master = item->u.ml.real_master; + extra_ref = item->u.ml.extra_ref; if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { /* this case is super-rare. only occurs if @@ -1517,6 +1537,12 @@ again: } leave: + /* See comment in dlm_mig_lockres_handler() */ + if (res) { + if (extra_ref) + dlm_lockres_put(res); + dlm_lockres_put(res); + } kfree(data); mlog_exit(ret); } @@ -1644,7 +1670,8 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data, /* retry!? */ BUG(); } - } + } else /* put.. incase we are not the master */ + dlm_lockres_put(res); spin_unlock(&res->spinlock); } spin_unlock(&dlm->spinlock); @@ -1921,6 +1948,7 @@ void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm, "Recovering res %s:%.*s, is already on recovery list!\n", dlm->name, res->lockname.len, res->lockname.name); list_del_init(&res->recovering); + dlm_lockres_put(res); } /* We need to hold a reference while on the recovery list */ dlm_lockres_get(res); |