1 files changed, 454 insertions, 139 deletions

diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
index 805cbabac051..29b2845f370d 100644
--- a/fs/ocfs2/dlm/dlmrecovery.c
+++ b/fs/ocfs2/dlm/dlmrecovery.c
@@ -98,8 +98,8 @@ static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data);
 
 static u64 dlm_get_next_mig_cookie(void);
 
-static spinlock_t dlm_reco_state_lock = SPIN_LOCK_UNLOCKED;
-static spinlock_t dlm_mig_cookie_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(dlm_reco_state_lock);
+static DEFINE_SPINLOCK(dlm_mig_cookie_lock);
 static u64 dlm_mig_cookie = 1;
 
 static u64 dlm_get_next_mig_cookie(void)
@@ -115,12 +115,37 @@ static u64 dlm_get_next_mig_cookie(void)
         return c;
 }
 
+static inline void dlm_set_reco_dead_node(struct dlm_ctxt *dlm,
+                                          u8 dead_node)
+{
+        assert_spin_locked(&dlm->spinlock);
+        if (dlm->reco.dead_node != dead_node)
+                mlog(0, "%s: changing dead_node from %u to %u\n",
+                     dlm->name, dlm->reco.dead_node, dead_node);
+        dlm->reco.dead_node = dead_node;
+}
+
+static inline void dlm_set_reco_master(struct dlm_ctxt *dlm,
+                                       u8 master)
+{
+        assert_spin_locked(&dlm->spinlock);
+        mlog(0, "%s: changing new_master from %u to %u\n",
+             dlm->name, dlm->reco.new_master, master);
+        dlm->reco.new_master = master;
+}
+
+static inline void __dlm_reset_recovery(struct dlm_ctxt *dlm)
+{
+        assert_spin_locked(&dlm->spinlock);
+        clear_bit(dlm->reco.dead_node, dlm->recovery_map);
+        dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
+        dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
+}
+
 static inline void dlm_reset_recovery(struct dlm_ctxt *dlm)
 {
         spin_lock(&dlm->spinlock);
-        clear_bit(dlm->reco.dead_node, dlm->recovery_map);
-        dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
-        dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
+        __dlm_reset_recovery(dlm);
         spin_unlock(&dlm->spinlock);
 }
 
@@ -132,12 +157,21 @@ void dlm_dispatch_work(void *data)
         struct list_head *iter, *iter2;
         struct dlm_work_item *item;
         dlm_workfunc_t *workfunc;
+        int tot=0;
+
+        if (!dlm_joined(dlm))
+                return;
 
         spin_lock(&dlm->work_lock);
         list_splice_init(&dlm->work_list, &tmp_list);
         spin_unlock(&dlm->work_lock);
 
         list_for_each_safe(iter, iter2, &tmp_list) {
+                tot++;
+        }
+        mlog(0, "%s: work thread has %d work items\n", dlm->name, tot);
+
+        list_for_each_safe(iter, iter2, &tmp_list) {
                 item = list_entry(iter, struct dlm_work_item, list);
                 workfunc = item->func;
                 list_del_init(&item->list);
@@ -220,6 +254,52 @@ void dlm_complete_recovery_thread(struct dlm_ctxt *dlm)
  *
  */
 
+static void dlm_print_reco_node_status(struct dlm_ctxt *dlm)
+{
+        struct dlm_reco_node_data *ndata;
+        struct dlm_lock_resource *res;
+
+        mlog(ML_NOTICE, "%s(%d): recovery info, state=%s, dead=%u, master=%u\n",
+             dlm->name, dlm->dlm_reco_thread_task->pid,
+             dlm->reco.state & DLM_RECO_STATE_ACTIVE ? "ACTIVE" : "inactive",
+             dlm->reco.dead_node, dlm->reco.new_master);
+
+        list_for_each_entry(ndata, &dlm->reco.node_data, list) {
+                char *st = "unknown";
+                switch (ndata->state) {
+                        case DLM_RECO_NODE_DATA_INIT:
+                                st = "init";
+                                break;
+                        case DLM_RECO_NODE_DATA_REQUESTING:
+                                st = "requesting";
+                                break;
+                        case DLM_RECO_NODE_DATA_DEAD:
+                                st = "dead";
+                                break;
+                        case DLM_RECO_NODE_DATA_RECEIVING:
+                                st = "receiving";
+                                break;
+                        case DLM_RECO_NODE_DATA_REQUESTED:
+                                st = "requested";
+                                break;
+                        case DLM_RECO_NODE_DATA_DONE:
+                                st = "done";
+                                break;
+                        case DLM_RECO_NODE_DATA_FINALIZE_SENT:
+                                st = "finalize-sent";
+                                break;
+                        default:
+                                st = "bad";
+                                break;
+                }
+                mlog(ML_NOTICE, "%s: reco state, node %u, state=%s\n",
+                     dlm->name, ndata->node_num, st);
+        }
+        list_for_each_entry(res, &dlm->reco.resources, recovering) {
+                mlog(ML_NOTICE, "%s: lockres %.*s on recovering list\n",
+                     dlm->name, res->lockname.len, res->lockname.name);
+        }
+}
 
 #define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000)
 
@@ -267,11 +347,23 @@ int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node)
 {
         int dead;
         spin_lock(&dlm->spinlock);
-        dead = test_bit(node, dlm->domain_map);
+        dead = !test_bit(node, dlm->domain_map);
         spin_unlock(&dlm->spinlock);
         return dead;
 }
 
+/* returns true if node is no longer in the domain
+ * could be dead or just not joined */
+static int dlm_is_node_recovered(struct dlm_ctxt *dlm, u8 node)
+{
+        int recovered;
+        spin_lock(&dlm->spinlock);
+        recovered = !test_bit(node, dlm->recovery_map);
+        spin_unlock(&dlm->spinlock);
+        return recovered;
+}
+
+
 int dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
 {
         if (timeout) {
@@ -290,6 +382,24 @@ int dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout)
         return 0;
 }
 
+int dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout)
+{
+        if (timeout) {
+                mlog(0, "%s: waiting %dms for notification of "
+                     "recovery of node %u\n", dlm->name, timeout, node);
+                wait_event_timeout(dlm->dlm_reco_thread_wq,
+                           dlm_is_node_recovered(dlm, node),
+                           msecs_to_jiffies(timeout));
+        } else {
+                mlog(0, "%s: waiting indefinitely for notification "
+                     "of recovery of node %u\n", dlm->name, node);
+                wait_event(dlm->dlm_reco_thread_wq,
+                           dlm_is_node_recovered(dlm, node));
+        }
+        /* for now, return 0 */
+        return 0;
+}
+
 /* callers of the top-level api calls (dlmlock/dlmunlock) should
  * block on the dlm->reco.event when recovery is in progress.
  * the dlm recovery thread will set this state when it begins
@@ -308,6 +418,13 @@ static int dlm_in_recovery(struct dlm_ctxt *dlm)
 
 void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
 {
+        if (dlm_in_recovery(dlm)) {
+                mlog(0, "%s: reco thread %d in recovery: "
+                     "state=%d, master=%u, dead=%u\n",
+                     dlm->name, dlm->dlm_reco_thread_task->pid,
+                     dlm->reco.state, dlm->reco.new_master,
+                     dlm->reco.dead_node);
+        }
         wait_event(dlm->reco.event, !dlm_in_recovery(dlm));
 }
 
@@ -341,7 +458,7 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
                 mlog(0, "new master %u died while recovering %u!\n",
                      dlm->reco.new_master, dlm->reco.dead_node);
                 /* unset the new_master, leave dead_node */
-                dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
+                dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
         }
 
         /* select a target to recover */
@@ -350,14 +467,14 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
 
                 bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES+1, 0);
                 if (bit >= O2NM_MAX_NODES || bit < 0)
-                        dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
+                        dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
                 else
-                        dlm->reco.dead_node = bit;
+                        dlm_set_reco_dead_node(dlm, bit);
         } else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) {
                 /* BUG? */
                 mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n",
                      dlm->reco.dead_node);
-                dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
+                dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
         }
 
         if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) {
@@ -366,7 +483,8 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
                 /* return to main thread loop and sleep. */
                 return 0;
         }
-        mlog(0, "recovery thread found node %u in the recovery map!\n",
+        mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
+             dlm->name, dlm->dlm_reco_thread_task->pid,
              dlm->reco.dead_node);
         spin_unlock(&dlm->spinlock);
 
@@ -389,8 +507,8 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
                 }
                 mlog(0, "another node will master this recovery session.\n");
         }
-        mlog(0, "dlm=%s, new_master=%u, this node=%u, dead_node=%u\n",
-             dlm->name, dlm->reco.new_master,
+        mlog(0, "dlm=%s (%d), new_master=%u, this node=%u, dead_node=%u\n",
+             dlm->name, dlm->dlm_reco_thread_task->pid, dlm->reco.new_master,
              dlm->node_num, dlm->reco.dead_node);
 
         /* it is safe to start everything back up here
@@ -402,11 +520,13 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
         return 0;
 
 master_here:
-        mlog(0, "mastering recovery of %s:%u here(this=%u)!\n",
+        mlog(0, "(%d) mastering recovery of %s:%u here(this=%u)!\n",
+             dlm->dlm_reco_thread_task->pid,
              dlm->name, dlm->reco.dead_node, dlm->node_num);
 
         status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
         if (status < 0) {
+                /* we should never hit this anymore */
                 mlog(ML_ERROR, "error %d remastering locks for node %u, "
                      "retrying.\n", status, dlm->reco.dead_node);
                 /* yield a bit to allow any final network messages
@@ -433,9 +553,16 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
         int destroy = 0;
         int pass = 0;
 
-        status = dlm_init_recovery_area(dlm, dead_node);
-        if (status < 0)
-                goto leave;
+        do {
+                /* we have become recovery master.  there is no escaping
+                 * this, so just keep trying until we get it. */
+                status = dlm_init_recovery_area(dlm, dead_node);
+                if (status < 0) {
+                        mlog(ML_ERROR, "%s: failed to alloc recovery area, "
+                             "retrying\n", dlm->name);
+                        msleep(1000);
+                }
+        } while (status != 0);
 
         /* safe to access the node data list without a lock, since this
          * process is the only one to change the list */
@@ -452,16 +579,36 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
                         continue;
                 }
 
-                status = dlm_request_all_locks(dlm, ndata->node_num, dead_node);
-                if (status < 0) {
-                        mlog_errno(status);
-                        if (dlm_is_host_down(status))
-                                ndata->state = DLM_RECO_NODE_DATA_DEAD;
-                        else {
-                                destroy = 1;
-                                goto leave;
+                do {
+                        status = dlm_request_all_locks(dlm, ndata->node_num,
+                                                       dead_node);
+                        if (status < 0) {
+                                mlog_errno(status);
+                                if (dlm_is_host_down(status)) {
+                                        /* node died, ignore it for recovery */
+                                        status = 0;
+                                        ndata->state = DLM_RECO_NODE_DATA_DEAD;
+                                        /* wait for the domain map to catch up
+                                         * with the network state. */
+                                        wait_event_timeout(dlm->dlm_reco_thread_wq,
+                                                           dlm_is_node_dead(dlm,
+                                                                ndata->node_num),
+                                                           msecs_to_jiffies(1000));
+                                        mlog(0, "waited 1 sec for %u, "
+                                             "dead? %s\n", ndata->node_num,
+                                             dlm_is_node_dead(dlm, ndata->node_num) ?
+                                             "yes" : "no");
+                                } else {
+                                        /* -ENOMEM on the other node */
+                                        mlog(0, "%s: node %u returned "
+                                             "%d during recovery, retrying "
+                                             "after a short wait\n",
+                                             dlm->name, ndata->node_num,
+                                             status);
+                                        msleep(100);
+                                }
                         }
-                }
+                } while (status != 0);
 
                 switch (ndata->state) {
                         case DLM_RECO_NODE_DATA_INIT:
@@ -473,10 +620,9 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
                                 mlog(0, "node %u died after requesting "
                                      "recovery info for node %u\n",
                                      ndata->node_num, dead_node);
-                                // start all over
-                                destroy = 1;
-                                status = -EAGAIN;
-                                goto leave;
+                                /* fine.  don't need this node's info.
+                                 * continue without it. */
+                                break;
                         case DLM_RECO_NODE_DATA_REQUESTING:
                                 ndata->state = DLM_RECO_NODE_DATA_REQUESTED;
                                 mlog(0, "now receiving recovery data from "
@@ -520,35 +666,26 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
                                         BUG();
                                         break;
                                 case DLM_RECO_NODE_DATA_DEAD:
-                                        mlog(ML_NOTICE, "node %u died after "
+                                        mlog(0, "node %u died after "
                                              "requesting recovery info for "
                                              "node %u\n", ndata->node_num,
                                              dead_node);
-                                        spin_unlock(&dlm_reco_state_lock);
-                                        // start all over
-                                        destroy = 1;
-                                        status = -EAGAIN;
-                                        /* instead of spinning like crazy here,
-                                         * wait for the domain map to catch up
-                                         * with the network state.  otherwise this
-                                         * can be hit hundreds of times before
-                                         * the node is really seen as dead. */
-                                        wait_event_timeout(dlm->dlm_reco_thread_wq,
-                                                           dlm_is_node_dead(dlm,
-                                                                ndata->node_num),
-                                                           msecs_to_jiffies(1000));
-                                        mlog(0, "waited 1 sec for %u, "
-                                             "dead? %s\n", ndata->node_num,
-                                             dlm_is_node_dead(dlm, ndata->node_num) ?
-                                             "yes" : "no");
-                                        goto leave;
+                                        break;
                                 case DLM_RECO_NODE_DATA_RECEIVING:
                                 case DLM_RECO_NODE_DATA_REQUESTED:
+                                        mlog(0, "%s: node %u still in state %s\n",
+                                             dlm->name, ndata->node_num,
+                                             ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
+                                             "receiving" : "requested");
                                         all_nodes_done = 0;
                                         break;
                                 case DLM_RECO_NODE_DATA_DONE:
+                                        mlog(0, "%s: node %u state is done\n",
+                                             dlm->name, ndata->node_num);
                                         break;
                                 case DLM_RECO_NODE_DATA_FINALIZE_SENT:
+                                        mlog(0, "%s: node %u state is finalize\n",
+                                             dlm->name, ndata->node_num);
                                         break;
                         }
                 }
@@ -578,7 +715,7 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
                              jiffies, dlm->reco.dead_node,
                              dlm->node_num, dlm->reco.new_master);
                         destroy = 1;
-                        status = ret;
+                        status = 0;
                         /* rescan everything marked dirty along the way */
                         dlm_kick_thread(dlm, NULL);
                         break;
@@ -591,7 +728,6 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node)
 
         }
 
-leave:
         if (destroy)
                 dlm_destroy_recovery_area(dlm, dead_node);
 
@@ -617,7 +753,7 @@ static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node)
                 }
                 BUG_ON(num == dead_node);
 
-                ndata = kcalloc(1, sizeof(*ndata), GFP_KERNEL);
+                ndata = kcalloc(1, sizeof(*ndata), GFP_NOFS);
                 if (!ndata) {
                         dlm_destroy_recovery_area(dlm, dead_node);
                         return -ENOMEM;
@@ -691,16 +827,25 @@ int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data)
         if (!dlm_grab(dlm))
                 return -EINVAL;
 
+        if (lr->dead_node != dlm->reco.dead_node) {
+                mlog(ML_ERROR, "%s: node %u sent dead_node=%u, but local "
+                     "dead_node is %u\n", dlm->name, lr->node_idx,
+                     lr->dead_node, dlm->reco.dead_node);
+                dlm_print_reco_node_status(dlm);
+                /* this is a hack */
+                dlm_put(dlm);
+                return -ENOMEM;
+        }
         BUG_ON(lr->dead_node != dlm->reco.dead_node);
 
-        item = kcalloc(1, sizeof(*item), GFP_KERNEL);
+        item = kcalloc(1, sizeof(*item), GFP_NOFS);
         if (!item) {
                 dlm_put(dlm);
                 return -ENOMEM;
         }
 
         /* this will get freed by dlm_request_all_locks_worker */
-        buf = (char *) __get_free_page(GFP_KERNEL);
+        buf = (char *) __get_free_page(GFP_NOFS);
         if (!buf) {
                 kfree(item);
                 dlm_put(dlm);
@@ -715,7 +860,7 @@ int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data)
         spin_lock(&dlm->work_lock);
         list_add_tail(&item->list, &dlm->work_list);
         spin_unlock(&dlm->work_lock);
-        schedule_work(&dlm->dispatched_work);
+        queue_work(dlm->dlm_worker, &dlm->dispatched_work);
 
         dlm_put(dlm);
         return 0;
@@ -730,32 +875,34 @@ static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
         struct list_head *iter;
         int ret;
         u8 dead_node, reco_master;
+        int skip_all_done = 0;
 
         dlm = item->dlm;
         dead_node = item->u.ral.dead_node;
         reco_master = item->u.ral.reco_master;
         mres = (struct dlm_migratable_lockres *)data;
 
+        mlog(0, "%s: recovery worker started, dead=%u, master=%u\n",
+             dlm->name, dead_node, reco_master);
+
         if (dead_node != dlm->reco.dead_node ||
             reco_master != dlm->reco.new_master) {
-                /* show extra debug info if the recovery state is messed */
-                mlog(ML_ERROR, "%s: bad reco state: reco(dead=%u, master=%u), "
-                     "request(dead=%u, master=%u)\n",
-                     dlm->name, dlm->reco.dead_node, dlm->reco.new_master,
-                     dead_node, reco_master);
-                mlog(ML_ERROR, "%s: name=%.*s master=%u locks=%u/%u flags=%u "
-                     "entry[0]={c=%u:%llu,l=%u,f=%u,t=%d,ct=%d,hb=%d,n=%u}\n",
-                     dlm->name, mres->lockname_len, mres->lockname, mres->master,
-                     mres->num_locks, mres->total_locks, mres->flags,
-                     dlm_get_lock_cookie_node(mres->ml[0].cookie),
-                     dlm_get_lock_cookie_seq(mres->ml[0].cookie),
-                     mres->ml[0].list, mres->ml[0].flags,
-                     mres->ml[0].type, mres->ml[0].convert_type,
-                     mres->ml[0].highest_blocked, mres->ml[0].node);
-                BUG();
+                /* worker could have been created before the recovery master
+                 * died.  if so, do not continue, but do not error. */
+                if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) {
+                        mlog(ML_NOTICE, "%s: will not send recovery state, "
+                             "recovery master %u died, thread=(dead=%u,mas=%u)"
+                             " current=(dead=%u,mas=%u)\n", dlm->name,
+                             reco_master, dead_node, reco_master,
+                             dlm->reco.dead_node, dlm->reco.new_master);
+                } else {
+                        mlog(ML_NOTICE, "%s: reco state invalid: reco(dead=%u, "
+                             "master=%u), request(dead=%u, master=%u)\n",
+                             dlm->name, dlm->reco.dead_node,
+                             dlm->reco.new_master, dead_node, reco_master);
+                }
+                goto leave;
         }
-        BUG_ON(dead_node != dlm->reco.dead_node);
-        BUG_ON(reco_master != dlm->reco.new_master);
 
         /* lock resources should have already been moved to the
          * dlm->reco.resources list.  now move items from that list
@@ -766,12 +913,20 @@ static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
         dlm_move_reco_locks_to_list(dlm, &resources, dead_node);
 
         /* now we can begin blasting lockreses without the dlm lock */
+
+        /* any errors returned will be due to the new_master dying,
+         * the dlm_reco_thread should detect this */
         list_for_each(iter, &resources) {
                 res = list_entry (iter, struct dlm_lock_resource, recovering);
                 ret = dlm_send_one_lockres(dlm, res, mres, reco_master,
                                         DLM_MRES_RECOVERY);
-                if (ret < 0)
-                        mlog_errno(ret);
+                if (ret < 0) {
+                        mlog(ML_ERROR, "%s: node %u went down while sending "
+                             "recovery state for dead node %u, ret=%d\n", dlm->name,
+                             reco_master, dead_node, ret);
+                        skip_all_done = 1;
+                        break;
+                }
         }
 
         /* move the resources back to the list */
@@ -779,10 +934,15 @@ static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data)
         list_splice_init(&resources, &dlm->reco.resources);
         spin_unlock(&dlm->spinlock);
 
-        ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
-        if (ret < 0)
-                mlog_errno(ret);
-
+        if (!skip_all_done) {
+                ret = dlm_send_all_done_msg(dlm, dead_node, reco_master);
+                if (ret < 0) {
+                        mlog(ML_ERROR, "%s: node %u went down while sending "
+                             "recovery all-done for dead node %u, ret=%d\n",
+                             dlm->name, reco_master, dead_node, ret);
+                }
+        }
+leave:
         free_page((unsigned long)data);
 }
 
@@ -801,8 +961,14 @@ static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to)
 
         ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg,
                                  sizeof(done_msg), send_to, &tmpret);
-        /* negative status is ignored by the caller */
-        if (ret >= 0)
+        if (ret < 0) {
+                if (!dlm_is_host_down(ret)) {
+                        mlog_errno(ret);
+                        mlog(ML_ERROR, "%s: unknown error sending data-done "
+                             "to %u\n", dlm->name, send_to);
+                        BUG();
+                }
+        } else
                 ret = tmpret;
         return ret;
 }
@@ -822,7 +988,11 @@ int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data)
         mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, "
              "node_idx=%u, this node=%u\n", done->dead_node,
              dlm->reco.dead_node, done->node_idx, dlm->node_num);
-        BUG_ON(done->dead_node != dlm->reco.dead_node);
+
+        mlog_bug_on_msg((done->dead_node != dlm->reco.dead_node),
+                        "Got DATA DONE: dead_node=%u, reco.dead_node=%u, "
+                        "node_idx=%u, this node=%u\n", done->dead_node,
+                        dlm->reco.dead_node, done->node_idx, dlm->node_num);
 
         spin_lock(&dlm_reco_state_lock);
         list_for_each(iter, &dlm->reco.node_data) {
@@ -905,13 +1075,11 @@ static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm,
                         mlog(0, "found lockres owned by dead node while "
                                   "doing recovery for node %u. sending it.\n",
                                   dead_node);
-                        list_del_init(&res->recovering);
-                        list_add_tail(&res->recovering, list);
+                        list_move_tail(&res->recovering, list);
                 } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
                         mlog(0, "found UNKNOWN owner while doing recovery "
                                   "for node %u. sending it.\n", dead_node);
-                        list_del_init(&res->recovering);
-                        list_add_tail(&res->recovering, list);
+                        list_move_tail(&res->recovering, list);
                 }
         }
         spin_unlock(&dlm->spinlock);
@@ -1023,8 +1191,9 @@ static int dlm_add_lock_to_array(struct dlm_lock *lock,
                     ml->type == LKM_PRMODE) {
                         /* if it is already set, this had better be a PR
                          * and it has to match */
-                        if (mres->lvb[0] && (ml->type == LKM_EXMODE ||
-                            memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))) {
+                        if (!dlm_lvb_is_empty(mres->lvb) &&
+                            (ml->type == LKM_EXMODE ||
+                             memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))) {
                                 mlog(ML_ERROR, "mismatched lvbs!\n");
                                 __dlm_print_one_lock_resource(lock->lockres);
                                 BUG();
@@ -1083,22 +1252,25 @@ int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
                          * we must send it immediately. */
                         ret = dlm_send_mig_lockres_msg(dlm, mres, send_to,
                                                        res, total_locks);
-                        if (ret < 0) {
-                                // TODO
-                                mlog(ML_ERROR, "dlm_send_mig_lockres_msg "
-                                     "returned %d, TODO\n", ret);
-                                BUG();
-                        }
+                        if (ret < 0)
+                                goto error;
                 }
         }
         /* flush any remaining locks */
         ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks);
-        if (ret < 0) {
-                // TODO
-                mlog(ML_ERROR, "dlm_send_mig_lockres_msg returned %d, "
-                     "TODO\n", ret);
+        if (ret < 0)
+                goto error;
+        return ret;
+
+error:
+        mlog(ML_ERROR, "%s: dlm_send_mig_lockres_msg returned %d\n",
+             dlm->name, ret);
+        if (!dlm_is_host_down(ret))
                 BUG();
-        }
+        mlog(0, "%s: node %u went down while sending %s "
+             "lockres %.*s\n", dlm->name, send_to,
+             flags & DLM_MRES_RECOVERY ?  "recovery" : "migration",
+             res->lockname.len, res->lockname.name);
         return ret;
 }
 
@@ -1146,8 +1318,8 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data)
                 mlog(0, "all done flag.  all lockres data received!\n");
 
         ret = -ENOMEM;
-        buf = kmalloc(be16_to_cpu(msg->data_len), GFP_KERNEL);
-        item = kcalloc(1, sizeof(*item), GFP_KERNEL);
+        buf = kmalloc(be16_to_cpu(msg->data_len), GFP_NOFS);
+        item = kcalloc(1, sizeof(*item), GFP_NOFS);
         if (!buf || !item)
                 goto leave;
 
@@ -1238,7 +1410,7 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data)
         spin_lock(&dlm->work_lock);
         list_add_tail(&item->list, &dlm->work_list);
         spin_unlock(&dlm->work_lock);
-        schedule_work(&dlm->dispatched_work);
+        queue_work(dlm->dlm_worker, &dlm->dispatched_work);
 
 leave:
         dlm_put(dlm);
@@ -1406,6 +1578,7 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data)
         struct dlm_ctxt *dlm = data;
         struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf;
         struct dlm_lock_resource *res = NULL;
+        unsigned int hash;
         int master = DLM_LOCK_RES_OWNER_UNKNOWN;
         u32 flags = DLM_ASSERT_MASTER_REQUERY;
 
@@ -1415,8 +1588,10 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data)
                 return master;
         }
 
+        hash = dlm_lockid_hash(req->name, req->namelen);
+
         spin_lock(&dlm->spinlock);
-        res = __dlm_lookup_lockres(dlm, req->name, req->namelen);
+        res = __dlm_lookup_lockres(dlm, req->name, req->namelen, hash);
         if (res) {
                 spin_lock(&res->spinlock);
                 master = res->owner;
@@ -1483,7 +1658,7 @@ static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
         struct dlm_lock *newlock = NULL;
         struct dlm_lockstatus *lksb = NULL;
         int ret = 0;
-        int i;
+        int i, bad;
         struct list_head *iter;
         struct dlm_lock *lock = NULL;
 
@@ -1529,8 +1704,7 @@ static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
 
                         /* move the lock to its proper place */
                         /* do not alter lock refcount.  switching lists. */
-                        list_del_init(&lock->list);
-                        list_add_tail(&lock->list, queue);
+                        list_move_tail(&lock->list, queue);
                         spin_unlock(&res->spinlock);
 
                         mlog(0, "just reordered a local lock!\n");
@@ -1553,28 +1727,48 @@ static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
                 }
                 lksb->flags |= (ml->flags &
                                 (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
-                        
-                if (mres->lvb[0]) {
+
+                if (ml->type == LKM_NLMODE)
+                        goto skip_lvb;
+
+                if (!dlm_lvb_is_empty(mres->lvb)) {
                         if (lksb->flags & DLM_LKSB_PUT_LVB) {
                                 /* other node was trying to update
                                  * lvb when node died.  recreate the
                                  * lksb with the updated lvb. */
                                 memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN);
+                                /* the lock resource lvb update must happen
+                                 * NOW, before the spinlock is dropped.
+                                 * we no longer wait for the AST to update
+                                 * the lvb. */
+                                memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
                         } else {
                                 /* otherwise, the node is sending its 
                                  * most recent valid lvb info */
                                 BUG_ON(ml->type != LKM_EXMODE &&
                                        ml->type != LKM_PRMODE);
-                                if (res->lvb[0] && (ml->type == LKM_EXMODE ||
-                                    memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
-                                        mlog(ML_ERROR, "received bad lvb!\n");
-                                        __dlm_print_one_lock_resource(res);
-                                        BUG();
+                                if (!dlm_lvb_is_empty(res->lvb) &&
+                                    (ml->type == LKM_EXMODE ||
+                                     memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) {
+                                        int i;
+                                        mlog(ML_ERROR, "%s:%.*s: received bad "
+                                             "lvb! type=%d\n", dlm->name,
+                                             res->lockname.len,
+                                             res->lockname.name, ml->type);
+                                        printk("lockres lvb=[");
+                                        for (i=0; i<DLM_LVB_LEN; i++)
+                                                printk("%02x", res->lvb[i]);
+                                        printk("]\nmigrated lvb=[");
+                                        for (i=0; i<DLM_LVB_LEN; i++)
+                                                printk("%02x", mres->lvb[i]);
+                                        printk("]\n");
+                                        dlm_print_one_lock_resource(res);
+                                        BUG();
                                 }
                                 memcpy(res->lvb, mres->lvb, DLM_LVB_LEN);
                         }
                 }
-
+skip_lvb:
 
                 /* NOTE:
                  * wrt lock queue ordering and recovery:
@@ -1592,9 +1786,33 @@ static int dlm_process_recovery_data(struct dlm_ctxt *dlm,
                  * relative to each other, but clearly *not*
                  * preserved relative to locks from other nodes.
                  */
+                bad = 0;
                 spin_lock(&res->spinlock);
-                dlm_lock_get(newlock);
-                list_add_tail(&newlock->list, queue);
+                list_for_each_entry(lock, queue, list) {
+                        if (lock->ml.cookie == ml->cookie) {
+                                u64 c = lock->ml.cookie;
+                                mlog(ML_ERROR, "%s:%.*s: %u:%llu: lock already "
+                                     "exists on this lockres!\n", dlm->name,
+                                     res->lockname.len, res->lockname.name,
+                                     dlm_get_lock_cookie_node(c),
+                                     dlm_get_lock_cookie_seq(c));
+
+                                mlog(ML_NOTICE, "sent lock: type=%d, conv=%d, "
+                                     "node=%u, cookie=%u:%llu, queue=%d\n",
+                                     ml->type, ml->convert_type, ml->node,
+                                     dlm_get_lock_cookie_node(ml->cookie),
+                                     dlm_get_lock_cookie_seq(ml->cookie),
+                                     ml->list);
+
+                                __dlm_print_one_lock_resource(res);
+                                bad = 1;
+                                break;
+                        }
+                }
+                if (!bad) {
+                        dlm_lock_get(newlock);
+                        list_add_tail(&newlock->list, queue);
+                }
                 spin_unlock(&res->spinlock);
         }
         mlog(0, "done running all the locks\n");
@@ -1618,8 +1836,14 @@ void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
         struct dlm_lock *lock;
 
         res->state |= DLM_LOCK_RES_RECOVERING;
-        if (!list_empty(&res->recovering))
+        if (!list_empty(&res->recovering)) {
+                mlog(0,
+                     "Recovering res %s:%.*s, is already on recovery list!\n",
+                     dlm->name, res->lockname.len, res->lockname.name);
                 list_del_init(&res->recovering);
+        }
+        /* We need to hold a reference while on the recovery list */
+        dlm_lockres_get(res);
         list_add_tail(&res->recovering, &dlm->reco.resources);
 
         /* find any pending locks and put them back on proper list */
@@ -1708,9 +1932,11 @@ static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
                         spin_lock(&res->spinlock);
                         dlm_change_lockres_owner(dlm, res, new_master);
                         res->state &= ~DLM_LOCK_RES_RECOVERING;
-                        __dlm_dirty_lockres(dlm, res);
+                        if (!__dlm_lockres_unused(res))
+                                __dlm_dirty_lockres(dlm, res);
                         spin_unlock(&res->spinlock);
                         wake_up(&res->wq);
+                        dlm_lockres_put(res);
                 }
         }
 
@@ -1719,7 +1945,7 @@ static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
          * the RECOVERING state and set the owner
          * if necessary */
         for (i = 0; i < DLM_HASH_BUCKETS; i++) {
-                bucket = &(dlm->lockres_hash[i]);
+                bucket = dlm_lockres_hash(dlm, i);
                 hlist_for_each_entry(res, hash_iter, bucket, hash_node) {
                         if (res->state & DLM_LOCK_RES_RECOVERING) {
                                 if (res->owner == dead_node) {
@@ -1743,11 +1969,13 @@ static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm,
                                              dlm->name, res->lockname.len,
                                              res->lockname.name, res->owner);
                                         list_del_init(&res->recovering);
+                                        dlm_lockres_put(res);
                                 }
                                 spin_lock(&res->spinlock);
                                 dlm_change_lockres_owner(dlm, res, new_master);
                                 res->state &= ~DLM_LOCK_RES_RECOVERING;
-                                __dlm_dirty_lockres(dlm, res);
+                                if (!__dlm_lockres_unused(res))
+                                        __dlm_dirty_lockres(dlm, res);
                                 spin_unlock(&res->spinlock);
                                 wake_up(&res->wq);
                         }
@@ -1884,7 +2112,7 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node)
          *    need to be fired as a result.
          */
         for (i = 0; i < DLM_HASH_BUCKETS; i++) {
-                bucket = &(dlm->lockres_hash[i]);
+                bucket = dlm_lockres_hash(dlm, i);
                 hlist_for_each_entry(res, iter, bucket, hash_node) {
                         /* always prune any $RECOVERY entries for dead nodes,
                          * otherwise hangs can occur during later recovery */
@@ -1924,6 +2152,20 @@ static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx)
 {
         assert_spin_locked(&dlm->spinlock);
 
+        if (dlm->reco.new_master == idx) {
+                mlog(0, "%s: recovery master %d just died\n",
+                     dlm->name, idx);
+                if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
+                        /* finalize1 was reached, so it is safe to clear
+                         * the new_master and dead_node.  that recovery
+                         * is complete. */
+                        mlog(0, "%s: dead master %d had reached "
+                             "finalize1 state, clearing\n", dlm->name, idx);
+                        dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
+                        __dlm_reset_recovery(dlm);
+                }
+        }
+
         /* check to see if the node is already considered dead */
         if (!test_bit(idx, dlm->live_nodes_map)) {
                 mlog(0, "for domain %s, node %d is already dead. "
@@ -2087,7 +2329,7 @@ again:
 
                         /* set the new_master to this node */
                         spin_lock(&dlm->spinlock);
-                        dlm->reco.new_master = dlm->node_num;
+                        dlm_set_reco_master(dlm, dlm->node_num);
                         spin_unlock(&dlm->spinlock);
                 }
 
@@ -2125,6 +2367,10 @@ again:
                 mlog(0, "%s: reco master %u is ready to recover %u\n",
                      dlm->name, dlm->reco.new_master, dlm->reco.dead_node);
                 status = -EEXIST;
+        } else if (ret == DLM_RECOVERING) {
+                mlog(0, "dlm=%s dlmlock says master node died (this=%u)\n",
+                     dlm->name, dlm->node_num);
+                goto again;
         } else {
                 struct dlm_lock_resource *res;
 
@@ -2156,7 +2402,7 @@ static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node)
 
         mlog_entry("%u\n", dead_node);
 
-        mlog(0, "dead node is %u\n", dead_node);
+        mlog(0, "%s: dead node is %u\n", dlm->name, dead_node);
 
         spin_lock(&dlm->spinlock);
         dlm_node_iter_init(dlm->domain_map, &iter);
@@ -2214,6 +2460,14 @@ retry:
                          * another ENOMEM */
                         msleep(100);
                         goto retry;
+                } else if (ret == EAGAIN) {
+                        mlog(0, "%s: trying to start recovery of node "
+                             "%u, but node %u is waiting for last recovery "
+                             "to complete, backoff for a bit\n", dlm->name,
+                             dead_node, nodenum);
+                        /* TODO Look into replacing msleep with cond_resched() */
+                        msleep(100);
+                        goto retry;
                 }
         }
 
@@ -2229,8 +2483,20 @@ int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data)
         if (!dlm_grab(dlm))
                 return 0;
 
-        mlog(0, "node %u wants to recover node %u\n",
-                  br->node_idx, br->dead_node);
+        spin_lock(&dlm->spinlock);
+        if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
+                mlog(0, "%s: node %u wants to recover node %u (%u:%u) "
+                     "but this node is in finalize state, waiting on finalize2\n",
+                     dlm->name, br->node_idx, br->dead_node,
+                     dlm->reco.dead_node, dlm->reco.new_master);
+                spin_unlock(&dlm->spinlock);
+                return EAGAIN;
+        }
+        spin_unlock(&dlm->spinlock);
+
+        mlog(0, "%s: node %u wants to recover node %u (%u:%u)\n",
+             dlm->name, br->node_idx, br->dead_node,
+             dlm->reco.dead_node, dlm->reco.new_master);
 
         dlm_fire_domain_eviction_callbacks(dlm, br->dead_node);
 
@@ -2252,8 +2518,8 @@ int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data)
                      "node %u changing it to %u\n", dlm->name, 
                      dlm->reco.dead_node, br->node_idx, br->dead_node);
         }
-        dlm->reco.new_master = br->node_idx;
-        dlm->reco.dead_node = br->dead_node;
+        dlm_set_reco_master(dlm, br->node_idx);
+        dlm_set_reco_dead_node(dlm, br->dead_node);
         if (!test_bit(br->dead_node, dlm->recovery_map)) {
                 mlog(0, "recovery master %u sees %u as dead, but this "
                      "node has not yet.  marking %u as dead\n",
@@ -2272,10 +2538,16 @@ int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data)
         spin_unlock(&dlm->spinlock);
 
         dlm_kick_recovery_thread(dlm);
+
+        mlog(0, "%s: recovery started by node %u, for %u (%u:%u)\n",
+             dlm->name, br->node_idx, br->dead_node,
+             dlm->reco.dead_node, dlm->reco.new_master);
+
         dlm_put(dlm);
         return 0;
 }
 
+#define DLM_FINALIZE_STAGE2  0x01
 static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
 {
         int ret = 0;
@@ -2283,25 +2555,31 @@ static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
         struct dlm_node_iter iter;
         int nodenum;
         int status;
+        int stage = 1;
 
-        mlog(0, "finishing recovery for node %s:%u\n",
-             dlm->name, dlm->reco.dead_node);
+        mlog(0, "finishing recovery for node %s:%u, "
+             "stage %d\n", dlm->name, dlm->reco.dead_node, stage);
 
         spin_lock(&dlm->spinlock);
         dlm_node_iter_init(dlm->domain_map, &iter);
         spin_unlock(&dlm->spinlock);
 
+stage2:
         memset(&fr, 0, sizeof(fr));
         fr.node_idx = dlm->node_num;
         fr.dead_node = dlm->reco.dead_node;
+        if (stage == 2)
+                fr.flags |= DLM_FINALIZE_STAGE2;
 
         while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
                 if (nodenum == dlm->node_num)
                         continue;
                 ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key,
                                          &fr, sizeof(fr), nodenum, &status);
-                if (ret >= 0) {
+                if (ret >= 0)
                         ret = status;
+                if (ret < 0) {
+                        mlog_errno(ret);
                         if (dlm_is_host_down(ret)) {
                                 /* this has no effect on this recovery 
                                  * session, so set the status to zero to 
@@ -2309,13 +2587,17 @@ static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm)
                                 mlog(ML_ERROR, "node %u went down after this "
                                      "node finished recovery.\n", nodenum);
                                 ret = 0;
+                                continue;
                         }
-                }
-                if (ret < 0) {
-                        mlog_errno(ret);
                         break;
                 }
         }
+        if (stage == 1) {
+                /* reset the node_iter back to the top and send finalize2 */
+                iter.curnode = -1;
+                stage = 2;
+                goto stage2;
+        }
 
         return ret;
 }
@@ -2324,14 +2606,19 @@ int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data)
 {
         struct dlm_ctxt *dlm = data;
         struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf;
+        int stage = 1;
 
         /* ok to return 0, domain has gone away */
         if (!dlm_grab(dlm))
                 return 0;
 
-        mlog(0, "node %u finalizing recovery of node %u\n",
-             fr->node_idx, fr->dead_node);
+        if (fr->flags & DLM_FINALIZE_STAGE2)
+                stage = 2;
 
+        mlog(0, "%s: node %u finalizing recovery stage%d of "
+             "node %u (%u:%u)\n", dlm->name, fr->node_idx, stage,
+             fr->dead_node, dlm->reco.dead_node, dlm->reco.new_master);
+ 
         spin_lock(&dlm->spinlock);
 
         if (dlm->reco.new_master != fr->node_idx) {
@@ -2347,13 +2634,41 @@ int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data)
                 BUG();
         }
 
-        dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
-
-        spin_unlock(&dlm->spinlock);
+        switch (stage) {
+                case 1:
+                        dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx);
+                        if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
+                                mlog(ML_ERROR, "%s: received finalize1 from "
+                                     "new master %u for dead node %u, but "
+                                     "this node has already received it!\n",
+                                     dlm->name, fr->node_idx, fr->dead_node);
+                                dlm_print_reco_node_status(dlm);
+                                BUG();
+                        }
+                        dlm->reco.state |= DLM_RECO_STATE_FINALIZE;
+                        spin_unlock(&dlm->spinlock);
+                        break;
+                case 2:
+                        if (!(dlm->reco.state & DLM_RECO_STATE_FINALIZE)) {
+                                mlog(ML_ERROR, "%s: received finalize2 from "
+                                     "new master %u for dead node %u, but "
+                                     "this node did not have finalize1!\n",
+                                     dlm->name, fr->node_idx, fr->dead_node);
+                                dlm_print_reco_node_status(dlm);
+                                BUG();
+                        }
+                        dlm->reco.state &= ~DLM_RECO_STATE_FINALIZE;
+                        spin_unlock(&dlm->spinlock);
+                        dlm_reset_recovery(dlm);
+                        dlm_kick_recovery_thread(dlm);
+                        break;
+                default:
+                        BUG();
+        }
 
-        dlm_reset_recovery(dlm);
+        mlog(0, "%s: recovery done, reco master was %u, dead now %u, master now %u\n",
+             dlm->name, fr->node_idx, dlm->reco.dead_node, dlm->reco.new_master);
 
-        dlm_kick_recovery_thread(dlm);
         dlm_put(dlm);
         return 0;
 }