Whamcloud - gitweb
LU-5398 ldlm: handle NULL lock in ldlm_handle_enqueue0()
[fs/lustre-release.git] / lustre / ldlm / ldlm_lockd.c
index 34cbf16..f56c776 100644 (file)
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -29,7 +27,7 @@
  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2011, 2012, Whamcloud, Inc.
+ * Copyright (c) 2010, 2013, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -41,9 +39,6 @@
  * Author: Phil Schwan <phil@clusterfs.com>
  */
 
-#ifndef EXPORT_SYMTAB
-# define EXPORT_SYMTAB
-#endif
 #define DEBUG_SUBSYSTEM S_LDLM
 
 #ifdef __KERNEL__
 #include <libcfs/list.h>
 #include "ldlm_internal.h"
 
-#ifdef __KERNEL__
 static int ldlm_num_threads;
 CFS_MODULE_PARM(ldlm_num_threads, "i", int, 0444,
                 "number of DLM service threads to start");
-#endif
 
-extern cfs_mem_cache_t *ldlm_resource_slab;
-extern cfs_mem_cache_t *ldlm_lock_slab;
-static cfs_mutex_t      ldlm_ref_mutex;
+static char *ldlm_cpts;
+CFS_MODULE_PARM(ldlm_cpts, "s", charp, 0444,
+               "CPU partitions ldlm threads should run on");
+
+extern struct kmem_cache *ldlm_resource_slab;
+extern struct kmem_cache *ldlm_lock_slab;
+static struct mutex    ldlm_ref_mutex;
 static int ldlm_refcount;
 
 struct ldlm_cb_async_args {
@@ -91,46 +88,32 @@ static inline unsigned int ldlm_get_rq_timeout(void)
         return timeout < 1 ? 1 : timeout;
 }
 
-#ifdef __KERNEL__
-/* w_l_spinlock protects both waiting_locks_list and expired_lock_thread */
-static cfs_spinlock_t waiting_locks_spinlock;   /* BH lock (timer) */
-static cfs_list_t waiting_locks_list;
-static cfs_timer_t waiting_locks_timer;
-
-static struct expired_lock_thread {
-        cfs_waitq_t               elt_waitq;
-        int                       elt_state;
-        int                       elt_dump;
-        cfs_list_t                elt_expired_locks;
-} expired_lock_thread;
-#endif
-
 #define ELT_STOPPED   0
 #define ELT_READY     1
 #define ELT_TERMINATE 2
 
 struct ldlm_bl_pool {
-        cfs_spinlock_t          blp_lock;
-
-        /*
-         * blp_prio_list is used for callbacks that should be handled
-         * as a priority. It is used for LDLM_FL_DISCARD_DATA requests.
-         * see bug 13843
-         */
-        cfs_list_t              blp_prio_list;
-
-        /*
-         * blp_list is used for all other callbacks which are likely
-         * to take longer to process.
-         */
-        cfs_list_t              blp_list;
-
-        cfs_waitq_t             blp_waitq;
-        cfs_completion_t        blp_comp;
-        cfs_atomic_t            blp_num_threads;
-        cfs_atomic_t            blp_busy_threads;
-        int                     blp_min_threads;
-        int                     blp_max_threads;
+       spinlock_t              blp_lock;
+
+       /*
+        * blp_prio_list is used for callbacks that should be handled
+        * as a priority. It is used for LDLM_FL_DISCARD_DATA requests.
+        * see bug 13843
+        */
+       cfs_list_t              blp_prio_list;
+
+       /*
+        * blp_list is used for all other callbacks which are likely
+        * to take longer to process.
+        */
+       cfs_list_t              blp_list;
+
+       wait_queue_head_t       blp_waitq;
+       struct completion       blp_comp;
+       atomic_t            blp_num_threads;
+       atomic_t            blp_busy_threads;
+       int                     blp_min_threads;
+       int                     blp_max_threads;
 };
 
 struct ldlm_bl_work_item {
@@ -140,116 +123,153 @@ struct ldlm_bl_work_item {
         struct ldlm_lock       *blwi_lock;
         cfs_list_t              blwi_head;
         int                     blwi_count;
-        cfs_completion_t        blwi_comp;
-        int                     blwi_mode;
+       struct completion        blwi_comp;
+       ldlm_cancel_flags_t     blwi_flags;
         int                     blwi_mem_pressure;
 };
 
-#ifdef __KERNEL__
+#if defined(HAVE_SERVER_SUPPORT) && defined(__KERNEL__)
+
+/**
+ * Protects both waiting_locks_list and expired_lock_thread.
+ */
+static spinlock_t waiting_locks_spinlock;   /* BH lock (timer) */
+
+/**
+ * List for contended locks.
+ *
+ * As soon as a lock is contended, it gets placed on this list and
+ * expected time to get a response is filled in the lock. A special
+ * thread walks the list looking for locks that should be released and
+ * schedules client evictions for those that have not been released in
+ * time.
+ *
+ * All access to it should be under waiting_locks_spinlock.
+ */
+static cfs_list_t waiting_locks_list;
+static struct timer_list waiting_locks_timer;
+
+static struct expired_lock_thread {
+       wait_queue_head_t       elt_waitq;
+       int                     elt_state;
+       int                     elt_dump;
+       cfs_list_t              elt_expired_locks;
+} expired_lock_thread;
 
 static inline int have_expired_locks(void)
 {
-        int need_to_run;
+       int need_to_run;
 
-        ENTRY;
-        cfs_spin_lock_bh(&waiting_locks_spinlock);
-        need_to_run = !cfs_list_empty(&expired_lock_thread.elt_expired_locks);
-        cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       ENTRY;
+       spin_lock_bh(&waiting_locks_spinlock);
+       need_to_run = !cfs_list_empty(&expired_lock_thread.elt_expired_locks);
+       spin_unlock_bh(&waiting_locks_spinlock);
 
-        RETURN(need_to_run);
+       RETURN(need_to_run);
 }
 
+/**
+ * Check expired lock list for expired locks and time them out.
+ */
 static int expired_lock_main(void *arg)
 {
-        cfs_list_t *expired = &expired_lock_thread.elt_expired_locks;
-        struct l_wait_info lwi = { 0 };
-        int do_dump;
-
-        ENTRY;
-        cfs_daemonize("ldlm_elt");
-
-        expired_lock_thread.elt_state = ELT_READY;
-        cfs_waitq_signal(&expired_lock_thread.elt_waitq);
-
-        while (1) {
-                l_wait_event(expired_lock_thread.elt_waitq,
-                             have_expired_locks() ||
-                             expired_lock_thread.elt_state == ELT_TERMINATE,
-                             &lwi);
-
-                cfs_spin_lock_bh(&waiting_locks_spinlock);
-                if (expired_lock_thread.elt_dump) {
-                        struct libcfs_debug_msg_data msgdata = {
-                                .msg_file = __FILE__,
-                                .msg_fn = "waiting_locks_callback",
-                                .msg_line = expired_lock_thread.elt_dump };
-                        cfs_spin_unlock_bh(&waiting_locks_spinlock);
-
-                        /* from waiting_locks_callback, but not in timer */
-                        libcfs_debug_dumplog();
-                        libcfs_run_lbug_upcall(&msgdata);
-
-                        cfs_spin_lock_bh(&waiting_locks_spinlock);
-                        expired_lock_thread.elt_dump = 0;
-                }
-
-                do_dump = 0;
-
-                while (!cfs_list_empty(expired)) {
-                        struct obd_export *export;
-                        struct ldlm_lock *lock;
-
-                        lock = cfs_list_entry(expired->next, struct ldlm_lock,
-                                          l_pending_chain);
-                        if ((void *)lock < LP_POISON + CFS_PAGE_SIZE &&
-                            (void *)lock >= LP_POISON) {
-                                cfs_spin_unlock_bh(&waiting_locks_spinlock);
-                                CERROR("free lock on elt list %p\n", lock);
-                                LBUG();
-                        }
-                        cfs_list_del_init(&lock->l_pending_chain);
-                        if ((void *)lock->l_export < LP_POISON + CFS_PAGE_SIZE &&
-                            (void *)lock->l_export >= LP_POISON) {
-                                CERROR("lock with free export on elt list %p\n",
-                                       lock->l_export);
-                                lock->l_export = NULL;
-                                LDLM_ERROR(lock, "free export");
-                                /* release extra ref grabbed by
-                                 * ldlm_add_waiting_lock() or
-                                 * ldlm_failed_ast() */
-                                LDLM_LOCK_RELEASE(lock);
-                                continue;
-                        }
-                        export = class_export_lock_get(lock->l_export, lock);
-                        cfs_spin_unlock_bh(&waiting_locks_spinlock);
-
-                        do_dump++;
-                        class_fail_export(export);
-                        class_export_lock_put(export, lock);
-
-                        /* release extra ref grabbed by ldlm_add_waiting_lock()
-                         * or ldlm_failed_ast() */
-                        LDLM_LOCK_RELEASE(lock);
-
-                        cfs_spin_lock_bh(&waiting_locks_spinlock);
-                }
-                cfs_spin_unlock_bh(&waiting_locks_spinlock);
-
-                if (do_dump && obd_dump_on_eviction) {
-                        CERROR("dump the log upon eviction\n");
-                        libcfs_debug_dumplog();
-                }
-
-                if (expired_lock_thread.elt_state == ELT_TERMINATE)
-                        break;
-        }
-
-        expired_lock_thread.elt_state = ELT_STOPPED;
-        cfs_waitq_signal(&expired_lock_thread.elt_waitq);
-        RETURN(0);
+       cfs_list_t *expired = &expired_lock_thread.elt_expired_locks;
+       struct l_wait_info lwi = { 0 };
+       int do_dump;
+
+       ENTRY;
+
+       expired_lock_thread.elt_state = ELT_READY;
+       wake_up(&expired_lock_thread.elt_waitq);
+
+       while (1) {
+               l_wait_event(expired_lock_thread.elt_waitq,
+                            have_expired_locks() ||
+                            expired_lock_thread.elt_state == ELT_TERMINATE,
+                            &lwi);
+
+               spin_lock_bh(&waiting_locks_spinlock);
+               if (expired_lock_thread.elt_dump) {
+                       struct libcfs_debug_msg_data msgdata = {
+                               .msg_file = __FILE__,
+                               .msg_fn = "waiting_locks_callback",
+                               .msg_line = expired_lock_thread.elt_dump };
+                       spin_unlock_bh(&waiting_locks_spinlock);
+
+                       /* from waiting_locks_callback, but not in timer */
+                       libcfs_debug_dumplog();
+                       libcfs_run_lbug_upcall(&msgdata);
+
+                       spin_lock_bh(&waiting_locks_spinlock);
+                       expired_lock_thread.elt_dump = 0;
+               }
+
+               do_dump = 0;
+
+               while (!cfs_list_empty(expired)) {
+                       struct obd_export *export;
+                       struct ldlm_lock *lock;
+
+                       lock = cfs_list_entry(expired->next, struct ldlm_lock,
+                                         l_pending_chain);
+                       if ((void *)lock < LP_POISON + PAGE_CACHE_SIZE &&
+                           (void *)lock >= LP_POISON) {
+                               spin_unlock_bh(&waiting_locks_spinlock);
+                               CERROR("free lock on elt list %p\n", lock);
+                               LBUG();
+                       }
+                       cfs_list_del_init(&lock->l_pending_chain);
+                       if ((void *)lock->l_export <
+                            LP_POISON + PAGE_CACHE_SIZE &&
+                           (void *)lock->l_export >= LP_POISON) {
+                               CERROR("lock with free export on elt list %p\n",
+                                      lock->l_export);
+                               lock->l_export = NULL;
+                               LDLM_ERROR(lock, "free export");
+                               /* release extra ref grabbed by
+                                * ldlm_add_waiting_lock() or
+                                * ldlm_failed_ast() */
+                               LDLM_LOCK_RELEASE(lock);
+                               continue;
+                       }
+
+                       if (ldlm_is_destroyed(lock)) {
+                               /* release the lock refcount where
+                                * waiting_locks_callback() founds */
+                               LDLM_LOCK_RELEASE(lock);
+                               continue;
+                       }
+                       export = class_export_lock_get(lock->l_export, lock);
+                       spin_unlock_bh(&waiting_locks_spinlock);
+
+                       do_dump++;
+                       class_fail_export(export);
+                       class_export_lock_put(export, lock);
+
+                       /* release extra ref grabbed by ldlm_add_waiting_lock()
+                        * or ldlm_failed_ast() */
+                       LDLM_LOCK_RELEASE(lock);
+
+                       spin_lock_bh(&waiting_locks_spinlock);
+               }
+               spin_unlock_bh(&waiting_locks_spinlock);
+
+               if (do_dump && obd_dump_on_eviction) {
+                       CERROR("dump the log upon eviction\n");
+                       libcfs_debug_dumplog();
+               }
+
+               if (expired_lock_thread.elt_state == ELT_TERMINATE)
+                       break;
+       }
+
+       expired_lock_thread.elt_state = ELT_STOPPED;
+       wake_up(&expired_lock_thread.elt_waitq);
+       RETURN(0);
 }
 
 static int ldlm_add_waiting_lock(struct ldlm_lock *lock);
+static int __ldlm_add_waiting_lock(struct ldlm_lock *lock, int seconds);
 
 /**
  * Check if there is a request in the export request list
@@ -257,33 +277,33 @@ static int ldlm_add_waiting_lock(struct ldlm_lock *lock);
  */
 static int ldlm_lock_busy(struct ldlm_lock *lock)
 {
-        struct ptlrpc_request *req;
-        int match = 0;
-        ENTRY;
+       struct ptlrpc_request *req;
+       int match = 0;
+       ENTRY;
 
-        if (lock->l_export == NULL)
-                return 0;
+       if (lock->l_export == NULL)
+               return 0;
 
-        cfs_spin_lock_bh(&lock->l_export->exp_rpc_lock);
-        cfs_list_for_each_entry(req, &lock->l_export->exp_hp_rpcs,
-                                rq_exp_list) {
-                if (req->rq_ops->hpreq_lock_match) {
-                        match = req->rq_ops->hpreq_lock_match(req, lock);
-                        if (match)
-                                break;
-                }
-        }
-        cfs_spin_unlock_bh(&lock->l_export->exp_rpc_lock);
-        RETURN(match);
+       spin_lock_bh(&lock->l_export->exp_rpc_lock);
+       cfs_list_for_each_entry(req, &lock->l_export->exp_hp_rpcs,
+                               rq_exp_list) {
+               if (req->rq_ops->hpreq_lock_match) {
+                       match = req->rq_ops->hpreq_lock_match(req, lock);
+                       if (match)
+                               break;
+               }
+       }
+       spin_unlock_bh(&lock->l_export->exp_rpc_lock);
+       RETURN(match);
 }
 
 /* This is called from within a timer interrupt and cannot schedule */
 static void waiting_locks_callback(unsigned long unused)
 {
-        struct ldlm_lock *lock;
+       struct ldlm_lock        *lock;
+       int                     need_dump = 0;
 
-repeat:
-        cfs_spin_lock_bh(&waiting_locks_spinlock);
+       spin_lock_bh(&waiting_locks_spinlock);
         while (!cfs_list_empty(&waiting_locks_list)) {
                 lock = cfs_list_entry(waiting_locks_list.next, struct ldlm_lock,
                                       l_pending_chain);
@@ -292,39 +312,6 @@ repeat:
                     (lock->l_req_mode == LCK_GROUP))
                         break;
 
-                if (ptlrpc_check_suspend()) {
-                        /* there is a case when we talk to one mds, holding
-                         * lock from another mds. this way we easily can get
-                         * here, if second mds is being recovered. so, we
-                         * suspend timeouts. bug 6019 */
-
-                        LDLM_ERROR(lock, "recharge timeout: %s@%s nid %s ",
-                                   lock->l_export->exp_client_uuid.uuid,
-                                   lock->l_export->exp_connection->c_remote_uuid.uuid,
-                                   libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid));
-
-                        cfs_list_del_init(&lock->l_pending_chain);
-                        cfs_spin_unlock_bh(&waiting_locks_spinlock);
-                        ldlm_add_waiting_lock(lock);
-                        goto repeat;
-                }
-
-                /* if timeout overlaps the activation time of suspended timeouts
-                 * then extend it to give a chance for client to reconnect */
-                if (cfs_time_before(cfs_time_sub(lock->l_callback_timeout,
-                                                 cfs_time_seconds(obd_timeout)/2),
-                                    ptlrpc_suspend_wakeup_time())) {
-                        LDLM_ERROR(lock, "extend timeout due to recovery: %s@%s nid %s ",
-                                   lock->l_export->exp_client_uuid.uuid,
-                                   lock->l_export->exp_connection->c_remote_uuid.uuid,
-                                   libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid));
-
-                        cfs_list_del_init(&lock->l_pending_chain);
-                        cfs_spin_unlock_bh(&waiting_locks_spinlock);
-                        ldlm_add_waiting_lock(lock);
-                        goto repeat;
-                }
-
                 /* Check if we need to prolong timeout */
                 if (!OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_HPREQ_TIMEOUT) &&
                     ldlm_lock_busy(lock)) {
@@ -335,11 +322,11 @@ repeat:
 
                         LDLM_LOCK_GET(lock);
 
-                        cfs_spin_unlock_bh(&waiting_locks_spinlock);
-                        LDLM_DEBUG(lock, "prolong the busy lock");
-                        ldlm_refresh_waiting_lock(lock,
-                                                  ldlm_get_enq_timeout(lock));
-                        cfs_spin_lock_bh(&waiting_locks_spinlock);
+                       spin_unlock_bh(&waiting_locks_spinlock);
+                       LDLM_DEBUG(lock, "prolong the busy lock");
+                       ldlm_refresh_waiting_lock(lock,
+                                                 ldlm_get_enq_timeout(lock));
+                       spin_lock_bh(&waiting_locks_spinlock);
 
                         if (!cont) {
                                 LDLM_LOCK_RELEASE(lock);
@@ -352,7 +339,7 @@ repeat:
                 ldlm_lock_to_ns(lock)->ns_timeouts++;
                 LDLM_ERROR(lock, "lock callback timer expired after %lds: "
                            "evicting client at %s ",
-                           cfs_time_current_sec()- lock->l_last_activity,
+                           cfs_time_current_sec() - lock->l_last_activity,
                            libcfs_nid2str(
                                    lock->l_export->exp_connection->c_peer.nid));
 
@@ -362,14 +349,15 @@ repeat:
                 cfs_list_del(&lock->l_pending_chain);
                 cfs_list_add(&lock->l_pending_chain,
                              &expired_lock_thread.elt_expired_locks);
-        }
+               need_dump = 1;
+       }
 
-        if (!cfs_list_empty(&expired_lock_thread.elt_expired_locks)) {
-                if (obd_dump_on_timeout)
-                        expired_lock_thread.elt_dump = __LINE__;
+       if (!cfs_list_empty(&expired_lock_thread.elt_expired_locks)) {
+               if (obd_dump_on_timeout && need_dump)
+                       expired_lock_thread.elt_dump = __LINE__;
 
-                cfs_waitq_signal(&expired_lock_thread.elt_waitq);
-        }
+               wake_up(&expired_lock_thread.elt_waitq);
+       }
 
         /*
          * Make sure the timer will fire again if we have any locks
@@ -382,10 +370,12 @@ repeat:
                 timeout_rounded = (cfs_time_t)round_timeout(lock->l_callback_timeout);
                 cfs_timer_arm(&waiting_locks_timer, timeout_rounded);
         }
-        cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       spin_unlock_bh(&waiting_locks_spinlock);
 }
 
-/*
+/**
+ * Add lock to the list of contended locks.
+ *
  * Indicate that we're waiting for a client to call us back cancelling a given
  * lock.  We add it to the pending-callback chain, and schedule the lock-timeout
  * timer to fire appropriately.  (We round up to the next second, to avoid
@@ -427,15 +417,19 @@ static int __ldlm_add_waiting_lock(struct ldlm_lock *lock, int seconds)
 
 static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
 {
-        int ret;
-        int timeout = ldlm_get_enq_timeout(lock);
+       int ret;
+       int timeout = ldlm_get_enq_timeout(lock);
+
+       /* NB: must be called with hold of lock_res_and_lock() */
+       LASSERT(ldlm_is_res_locked(lock));
+       ldlm_set_waited(lock);
 
-        LASSERT(!(lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK));
+       LASSERT(!ldlm_is_cancel_on_block(lock));
 
-        cfs_spin_lock_bh(&waiting_locks_spinlock);
-        if (lock->l_destroyed) {
-                static cfs_time_t next;
-                cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       spin_lock_bh(&waiting_locks_spinlock);
+       if (ldlm_is_destroyed(lock)) {
+               static cfs_time_t next;
+               spin_unlock_bh(&waiting_locks_spinlock);
                 LDLM_ERROR(lock, "not waiting on destroyed lock (bug 5653)");
                 if (cfs_time_after(cfs_time_current(), next)) {
                         next = cfs_time_shift(14400);
@@ -450,23 +444,23 @@ static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
                  * waiting list */
                 LDLM_LOCK_GET(lock);
         }
-        cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       spin_unlock_bh(&waiting_locks_spinlock);
 
-        if (ret) {
-                cfs_spin_lock_bh(&lock->l_export->exp_bl_list_lock);
-                if (cfs_list_empty(&lock->l_exp_list))
-                        cfs_list_add(&lock->l_exp_list,
-                                     &lock->l_export->exp_bl_list);
-                cfs_spin_unlock_bh(&lock->l_export->exp_bl_list_lock);
-        }
+       if (ret) {
+               spin_lock_bh(&lock->l_export->exp_bl_list_lock);
+               if (cfs_list_empty(&lock->l_exp_list))
+                       cfs_list_add(&lock->l_exp_list,
+                                    &lock->l_export->exp_bl_list);
+               spin_unlock_bh(&lock->l_export->exp_bl_list_lock);
+       }
 
-        LDLM_DEBUG(lock, "%sadding to wait list(timeout: %d, AT: %s)",
-                   ret == 0 ? "not re-" : "", timeout,
-                   AT_OFF ? "off" : "on");
-        return ret;
+       LDLM_DEBUG(lock, "%sadding to wait list(timeout: %d, AT: %s)",
+                  ret == 0 ? "not re-" : "", timeout,
+                  AT_OFF ? "off" : "on");
+       return ret;
 }
 
-/*
+/**
  * Remove a lock from the pending list, likely because it had its cancellation
  * callback arrive without incident.  This adjusts the lock-timeout timer if
  * needed.  Returns 0 if the lock wasn't pending after all, 1 if it was.
@@ -511,14 +505,14 @@ int ldlm_del_waiting_lock(struct ldlm_lock *lock)
                 return 0;
         }
 
-        cfs_spin_lock_bh(&waiting_locks_spinlock);
-        ret = __ldlm_del_waiting_lock(lock);
-        cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       spin_lock_bh(&waiting_locks_spinlock);
+       ret = __ldlm_del_waiting_lock(lock);
+       spin_unlock_bh(&waiting_locks_spinlock);
 
-        /* remove the lock out of export blocking list */
-        cfs_spin_lock_bh(&lock->l_export->exp_bl_list_lock);
-        cfs_list_del_init(&lock->l_exp_list);
-        cfs_spin_unlock_bh(&lock->l_export->exp_bl_list_lock);
+       /* remove the lock out of export blocking list */
+       spin_lock_bh(&lock->l_export->exp_bl_list_lock);
+       cfs_list_del_init(&lock->l_exp_list);
+       spin_unlock_bh(&lock->l_export->exp_bl_list_lock);
 
         if (ret) {
                 /* release lock ref if it has indeed been removed
@@ -529,44 +523,41 @@ int ldlm_del_waiting_lock(struct ldlm_lock *lock)
         LDLM_DEBUG(lock, "%s", ret == 0 ? "wasn't waiting" : "removed");
         return ret;
 }
+EXPORT_SYMBOL(ldlm_del_waiting_lock);
 
-/*
- * Prolong the lock
+/**
+ * Prolong the contended lock waiting time.
  *
  * Called with namespace lock held.
  */
 int ldlm_refresh_waiting_lock(struct ldlm_lock *lock, int timeout)
 {
-        if (lock->l_export == NULL) {
-                /* We don't have a "waiting locks list" on clients. */
-                LDLM_DEBUG(lock, "client lock: no-op");
-                return 0;
-        }
+       if (lock->l_export == NULL) {
+               /* We don't have a "waiting locks list" on clients. */
+               LDLM_DEBUG(lock, "client lock: no-op");
+               return 0;
+       }
 
-        cfs_spin_lock_bh(&waiting_locks_spinlock);
+       spin_lock_bh(&waiting_locks_spinlock);
 
-        if (cfs_list_empty(&lock->l_pending_chain)) {
-                cfs_spin_unlock_bh(&waiting_locks_spinlock);
-                LDLM_DEBUG(lock, "wasn't waiting");
-                return 0;
-        }
+       if (cfs_list_empty(&lock->l_pending_chain)) {
+               spin_unlock_bh(&waiting_locks_spinlock);
+               LDLM_DEBUG(lock, "wasn't waiting");
+               return 0;
+       }
 
-        /* we remove/add the lock to the waiting list, so no needs to
-         * release/take a lock reference */
-        __ldlm_del_waiting_lock(lock);
-        __ldlm_add_waiting_lock(lock, timeout);
-        cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       /* we remove/add the lock to the waiting list, so no needs to
+        * release/take a lock reference */
+       __ldlm_del_waiting_lock(lock);
+       __ldlm_add_waiting_lock(lock, timeout);
+       spin_unlock_bh(&waiting_locks_spinlock);
 
-        LDLM_DEBUG(lock, "refreshed");
-        return 1;
+       LDLM_DEBUG(lock, "refreshed");
+       return 1;
 }
-#else /* !__KERNEL__ */
+EXPORT_SYMBOL(ldlm_refresh_waiting_lock);
 
-static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
-{
-        LASSERT(!(lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK));
-        RETURN(1);
-}
+#else /* !HAVE_SERVER_SUPPORT ||  !__KERNEL__ */
 
 int ldlm_del_waiting_lock(struct ldlm_lock *lock)
 {
@@ -577,8 +568,22 @@ int ldlm_refresh_waiting_lock(struct ldlm_lock *lock, int timeout)
 {
         RETURN(0);
 }
-#endif /* __KERNEL__ */
 
+# ifdef HAVE_SERVER_SUPPORT
+static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
+{
+       LASSERT(ldlm_is_res_locked(lock) && !ldlm_is_cancel_on_block(lock));
+       RETURN(1);
+}
+
+# endif
+#endif /* HAVE_SERVER_SUPPORT && __KERNEL__ */
+
+#ifdef HAVE_SERVER_SUPPORT
+
+/**
+ * Perform lock cleanup if AST sending failed.
+ */
 static void ldlm_failed_ast(struct ldlm_lock *lock, int rc,
                             const char *ast_type)
 {
@@ -590,20 +595,23 @@ static void ldlm_failed_ast(struct ldlm_lock *lock, int rc,
         if (obd_dump_on_timeout)
                 libcfs_debug_dumplog();
 #ifdef __KERNEL__
-        cfs_spin_lock_bh(&waiting_locks_spinlock);
-        if (__ldlm_del_waiting_lock(lock) == 0)
-                /* the lock was not in any list, grab an extra ref before adding
-                 * the lock to the expired list */
-                LDLM_LOCK_GET(lock);
-        cfs_list_add(&lock->l_pending_chain,
-                     &expired_lock_thread.elt_expired_locks);
-        cfs_waitq_signal(&expired_lock_thread.elt_waitq);
-        cfs_spin_unlock_bh(&waiting_locks_spinlock);
+       spin_lock_bh(&waiting_locks_spinlock);
+       if (__ldlm_del_waiting_lock(lock) == 0)
+               /* the lock was not in any list, grab an extra ref before adding
+                * the lock to the expired list */
+               LDLM_LOCK_GET(lock);
+       cfs_list_add(&lock->l_pending_chain,
+                    &expired_lock_thread.elt_expired_locks);
+       wake_up(&expired_lock_thread.elt_waitq);
+       spin_unlock_bh(&waiting_locks_spinlock);
 #else
-        class_fail_export(lock->l_export);
+       class_fail_export(lock->l_export);
 #endif
 }
 
+/**
+ * Perform lock cleanup if AST reply came with error.
+ */
 static int ldlm_handle_ast_error(struct ldlm_lock *lock,
                                  struct ptlrpc_request *req, int rc,
                                  const char *ast_type)
@@ -618,7 +626,7 @@ static int ldlm_handle_ast_error(struct ldlm_lock *lock,
                                    libcfs_nid2str(peer.nid));
                         ldlm_lock_cancel(lock);
                         rc = -ERESTART;
-                } else if (lock->l_flags & LDLM_FL_CANCEL) {
+               } else if (ldlm_is_cancel(lock)) {
                         LDLM_DEBUG(lock, "%s AST timeout from nid %s, but "
                                    "cancel was received (AST reply lost?)",
                                    ast_type, libcfs_nid2str(peer.nid));
@@ -670,43 +678,69 @@ static int ldlm_cb_interpret(const struct lu_env *env,
         ENTRY;
 
         LASSERT(lock != NULL);
-        if (rc != 0) {
-                rc = ldlm_handle_ast_error(lock, req, rc,
-                                           arg->type == LDLM_BL_CALLBACK
-                                           ? "blocking" : "completion");
-                if (rc == -ERESTART)
-                        cfs_atomic_inc(&arg->restart);
-        }
+
+       switch (arg->type) {
+       case LDLM_GL_CALLBACK:
+               /* Update the LVB from disk if the AST failed
+                * (this is a legal race)
+                *
+                * - Glimpse callback of local lock just returns
+                *   -ELDLM_NO_LOCK_DATA.
+                * - Glimpse callback of remote lock might return
+                *   -ELDLM_NO_LOCK_DATA when inode is cleared. LU-274
+                */
+               if (rc == -ELDLM_NO_LOCK_DATA) {
+                       LDLM_DEBUG(lock, "lost race - client has a lock but no "
+                                  "inode");
+                       ldlm_res_lvbo_update(lock->l_resource, NULL, 1);
+               } else if (rc != 0) {
+                       rc = ldlm_handle_ast_error(lock, req, rc, "glimpse");
+               } else {
+                       rc = ldlm_res_lvbo_update(lock->l_resource, req, 1);
+               }
+               break;
+       case LDLM_BL_CALLBACK:
+               if (rc != 0)
+                       rc = ldlm_handle_ast_error(lock, req, rc, "blocking");
+               break;
+       case LDLM_CP_CALLBACK:
+               if (rc != 0)
+                       rc = ldlm_handle_ast_error(lock, req, rc, "completion");
+               break;
+       default:
+               LDLM_ERROR(lock, "invalid opcode for lock callback %d",
+                          arg->type);
+               LBUG();
+       }
+
+       /* release extra reference taken in ldlm_ast_fini() */
         LDLM_LOCK_RELEASE(lock);
 
-        if (cfs_atomic_dec_return(&arg->rpcs) < arg->threshold)
-                cfs_waitq_signal(&arg->waitq);
+       if (rc == -ERESTART)
+               atomic_inc(&arg->restart);
 
-        ldlm_csa_put(arg);
-        RETURN(0);
+       RETURN(0);
 }
 
-static inline int ldlm_bl_and_cp_ast_tail(struct ptlrpc_request *req,
-                                          struct ldlm_cb_set_arg *arg,
-                                          struct ldlm_lock *lock,
-                                          int instant_cancel)
+static inline int ldlm_ast_fini(struct ptlrpc_request *req,
+                               struct ldlm_cb_set_arg *arg,
+                               struct ldlm_lock *lock,
+                               int instant_cancel)
 {
-        int rc = 0;
-        ENTRY;
+       int rc = 0;
+       ENTRY;
 
-        if (unlikely(instant_cancel)) {
-                rc = ptl_send_rpc(req, 1);
-                ptlrpc_req_finished(req);
-                if (rc == 0)
-                        cfs_atomic_inc(&arg->restart);
-        } else {
-                LDLM_LOCK_GET(lock);
-                cfs_atomic_inc(&arg->rpcs);
-                cfs_atomic_inc(&arg->refcount);
-                ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
-        }
+       if (unlikely(instant_cancel)) {
+               rc = ptl_send_rpc(req, 1);
+               ptlrpc_req_finished(req);
+               if (rc == 0)
+                       atomic_inc(&arg->restart);
+       } else {
+               LDLM_LOCK_GET(lock);
+               ptlrpc_set_add_req(arg->set, req);
+       }
 
-        RETURN(rc);
+       RETURN(rc);
 }
 
 /**
@@ -715,34 +749,37 @@ static inline int ldlm_bl_and_cp_ast_tail(struct ptlrpc_request *req,
  */
 static void ldlm_lock_reorder_req(struct ldlm_lock *lock)
 {
-        struct ptlrpc_request *req;
-        ENTRY;
-
-        if (lock->l_export == NULL) {
-                LDLM_DEBUG(lock, "client lock: no-op");
-                RETURN_EXIT;
-        }
-
-        cfs_spin_lock_bh(&lock->l_export->exp_rpc_lock);
-        cfs_list_for_each_entry(req, &lock->l_export->exp_hp_rpcs,
-                                rq_exp_list) {
-                /* Do not process requests that were not yet added to there
-                 * incoming queue or were already removed from there for
-                 * processing */
-                if (!req->rq_hp && !cfs_list_empty(&req->rq_list) &&
-                    req->rq_ops->hpreq_lock_match &&
-                    req->rq_ops->hpreq_lock_match(req, lock))
-                        ptlrpc_hpreq_reorder(req);
-        }
-        cfs_spin_unlock_bh(&lock->l_export->exp_rpc_lock);
-        EXIT;
+       struct ptlrpc_request *req;
+       ENTRY;
+
+       if (lock->l_export == NULL) {
+               LDLM_DEBUG(lock, "client lock: no-op");
+               RETURN_EXIT;
+       }
+
+       spin_lock_bh(&lock->l_export->exp_rpc_lock);
+       cfs_list_for_each_entry(req, &lock->l_export->exp_hp_rpcs,
+                               rq_exp_list) {
+               /* Do not process requests that were not yet added to there
+                * incoming queue or were already removed from there for
+                * processing. We evaluate ptlrpc_nrs_req_can_move() without
+                * holding svcpt->scp_req_lock, and then redo the check with
+                * the lock held once we need to obtain a reliable result.
+                */
+               if (ptlrpc_nrs_req_can_move(req) &&
+                   req->rq_ops->hpreq_lock_match &&
+                   req->rq_ops->hpreq_lock_match(req, lock))
+                       ptlrpc_nrs_req_hp_move(req);
+       }
+       spin_unlock_bh(&lock->l_export->exp_rpc_lock);
+       EXIT;
 }
 
-/*
+/**
  * ->l_blocking_ast() method for server-side locks. This is invoked when newly
  * enqueued server lock conflicts with given one.
  *
- * Sends blocking ast rpc to the client owning that lock; arms timeout timer
+ * Sends blocking AST RPC to the client owning that lock; arms timeout timer
  * to wait for client response.
  */
 int ldlm_server_blocking_ast(struct ldlm_lock *lock,
@@ -763,10 +800,8 @@ int ldlm_server_blocking_ast(struct ldlm_lock *lock,
 
         LASSERT(lock);
         LASSERT(data != NULL);
-        if (lock->l_export->exp_obd->obd_recovering != 0) {
+        if (lock->l_export->exp_obd->obd_recovering != 0)
                 LDLM_ERROR(lock, "BUG 6063: lock collide during recovery");
-                ldlm_lock_dump(D_ERROR, lock, 0);
-        }
 
         ldlm_lock_reorder_req(lock);
 
@@ -784,59 +819,70 @@ int ldlm_server_blocking_ast(struct ldlm_lock *lock,
         req->rq_interpret_reply = ldlm_cb_interpret;
         req->rq_no_resend = 1;
 
-        lock_res(lock->l_resource);
-        if (lock->l_granted_mode != lock->l_req_mode) {
-                /* this blocking AST will be communicated as part of the
-                 * completion AST instead */
-                unlock_res(lock->l_resource);
-                ptlrpc_req_finished(req);
-                LDLM_DEBUG(lock, "lock not granted, not sending blocking AST");
-                RETURN(0);
-        }
-
-        if (lock->l_destroyed) {
-                /* What's the point? */
-                unlock_res(lock->l_resource);
-                ptlrpc_req_finished(req);
-                RETURN(0);
-        }
-
-        if (lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK)
+       lock_res_and_lock(lock);
+       if (lock->l_granted_mode != lock->l_req_mode) {
+               /* this blocking AST will be communicated as part of the
+                * completion AST instead */
+               unlock_res_and_lock(lock);
+
+               ptlrpc_req_finished(req);
+               LDLM_DEBUG(lock, "lock not granted, not sending blocking AST");
+               RETURN(0);
+       }
+
+       if (ldlm_is_destroyed(lock)) {
+               /* What's the point? */
+               unlock_res_and_lock(lock);
+               ptlrpc_req_finished(req);
+               RETURN(0);
+       }
+
+       if (ldlm_is_cancel_on_block(lock))
                 instant_cancel = 1;
 
         body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
         body->lock_handle[0] = lock->l_remote_handle;
         body->lock_desc = *desc;
-        body->lock_flags |= (lock->l_flags & LDLM_AST_FLAGS);
+       body->lock_flags |= ldlm_flags_to_wire(lock->l_flags & LDLM_FL_AST_MASK);
 
         LDLM_DEBUG(lock, "server preparing blocking AST");
 
         ptlrpc_request_set_replen(req);
-        if (instant_cancel) {
-                unlock_res(lock->l_resource);
-                ldlm_lock_cancel(lock);
-        } else {
-                LASSERT(lock->l_granted_mode == lock->l_req_mode);
-                ldlm_add_waiting_lock(lock);
-                unlock_res(lock->l_resource);
-        }
+       if (instant_cancel) {
+               unlock_res_and_lock(lock);
+               ldlm_lock_cancel(lock);
+       } else {
+               LASSERT(lock->l_granted_mode == lock->l_req_mode);
+               ldlm_add_waiting_lock(lock);
+               unlock_res_and_lock(lock);
+       }
 
         req->rq_send_state = LUSTRE_IMP_FULL;
         /* ptlrpc_request_alloc_pack already set timeout */
         if (AT_OFF)
                 req->rq_timeout = ldlm_get_rq_timeout();
 
+       lock->l_last_activity = cfs_time_current_sec();
+
         if (lock->l_export && lock->l_export->exp_nid_stats &&
             lock->l_export->exp_nid_stats->nid_ldlm_stats)
                 lprocfs_counter_incr(lock->l_export->exp_nid_stats->nid_ldlm_stats,
                                      LDLM_BL_CALLBACK - LDLM_FIRST_OPC);
 
-        rc = ldlm_bl_and_cp_ast_tail(req, arg, lock, instant_cancel);
+       rc = ldlm_ast_fini(req, arg, lock, instant_cancel);
 
         RETURN(rc);
 }
+EXPORT_SYMBOL(ldlm_server_blocking_ast);
 
-int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
+/**
+ * ->l_completion_ast callback for a remote lock in server namespace.
+ *
+ *  Sends AST to the client notifying it of lock granting.  If initial
+ *  lock response was not sent yet, instead of sending another RPC, just
+ *  mark the lock as granted and client will understand
+ */
+int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
 {
         struct ldlm_cb_set_arg *arg = data;
         struct ldlm_request    *body;
@@ -845,6 +891,7 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
         long                    total_enqueue_wait;
         int                     instant_cancel = 0;
         int                     rc = 0;
+       int                     lvb_len;
         ENTRY;
 
         LASSERT(lock != NULL);
@@ -853,17 +900,26 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
         total_enqueue_wait = cfs_time_sub(cfs_time_current_sec(),
                                           lock->l_last_activity);
 
+       if (OBD_FAIL_PRECHECK(OBD_FAIL_OST_LDLM_REPLY_NET)) {
+               LDLM_DEBUG(lock, "dropping CP AST");
+               RETURN(0);
+       }
+
         req = ptlrpc_request_alloc(lock->l_export->exp_imp_reverse,
                                     &RQF_LDLM_CP_CALLBACK);
         if (req == NULL)
                 RETURN(-ENOMEM);
 
-        /* server namespace, doesn't need lock */
-        if (lock->l_resource->lr_lvb_len) {
-                 req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_CLIENT,
-                                      lock->l_resource->lr_lvb_len);
-        }
+       /* server namespace, doesn't need lock */
+       lvb_len = ldlm_lvbo_size(lock);
+       /* LU-3124 & LU-2187: to not return layout in completion AST because
+        * it may deadlock for LU-2187, or client may not have enough space
+        * for large layout. The layout will be returned to client with an
+        * extra RPC to fetch xattr.lov */
+       if (ldlm_has_layout(lock))
+               lvb_len = 0;
 
+       req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_CLIENT, lvb_len);
         rc = ptlrpc_request_pack(req, LUSTRE_DLM_VERSION, LDLM_CP_CALLBACK);
         if (rc) {
                 ptlrpc_request_free(req);
@@ -880,20 +936,33 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
         body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
 
         body->lock_handle[0] = lock->l_remote_handle;
-        body->lock_flags = flags;
+       body->lock_flags = ldlm_flags_to_wire(flags);
         ldlm_lock2desc(lock, &body->lock_desc);
-        if (lock->l_resource->lr_lvb_len) {
-                void *lvb = req_capsule_client_get(&req->rq_pill, &RMF_DLM_LVB);
-
-                lock_res(lock->l_resource);
-                memcpy(lvb, lock->l_resource->lr_lvb_data,
-                       lock->l_resource->lr_lvb_len);
-                unlock_res(lock->l_resource);
+       if (lvb_len > 0) {
+               void *lvb = req_capsule_client_get(&req->rq_pill, &RMF_DLM_LVB);
+
+               lvb_len = ldlm_lvbo_fill(lock, lvb, lvb_len);
+               if (lvb_len < 0) {
+                       /* We still need to send the RPC to wake up the blocked
+                        * enqueue thread on the client.
+                        *
+                        * Consider old client, there is no better way to notify
+                        * the failure, just zero-sized the LVB, then the client
+                        * will fail out as "-EPROTO". */
+                       req_capsule_shrink(&req->rq_pill, &RMF_DLM_LVB, 0,
+                                          RCL_CLIENT);
+                       instant_cancel = 1;
+               } else {
+                       req_capsule_shrink(&req->rq_pill, &RMF_DLM_LVB, lvb_len,
+                                          RCL_CLIENT);
+               }
         }
 
         LDLM_DEBUG(lock, "server preparing completion AST (after %lds wait)",
                    total_enqueue_wait);
 
+       lock->l_last_activity = cfs_time_current_sec();
+
         /* Server-side enqueue wait time estimate, used in
             __ldlm_add_waiting_lock to set future enqueue timers */
         if (total_enqueue_wait < ldlm_get_enq_timeout(lock))
@@ -918,10 +987,11 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
 
         /* We only send real blocking ASTs after the lock is granted */
         lock_res_and_lock(lock);
-        if (lock->l_flags & LDLM_FL_AST_SENT) {
-                body->lock_flags |= LDLM_FL_AST_SENT;
-                /* copy ast flags like LDLM_FL_DISCARD_DATA */
-                body->lock_flags |= (lock->l_flags & LDLM_AST_FLAGS);
+       if (ldlm_is_ast_sent(lock)) {
+               body->lock_flags |= ldlm_flags_to_wire(LDLM_FL_AST_SENT);
+               /* Copy AST flags like LDLM_FL_DISCARD_DATA. */
+               body->lock_flags |= ldlm_flags_to_wire(lock->l_flags &
+                                                      LDLM_FL_AST_MASK);
 
                 /* We might get here prior to ldlm_handle_enqueue setting
                  * LDLM_FL_CANCEL_ON_BLOCK flag. Then we will put this lock
@@ -929,7 +999,7 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
                  * ldlm_handle_enqueue will call ldlm_lock_cancel() still,
                  * that would not only cancel the lock, but will also remove
                  * it from waiting list */
-                if (lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK) {
+               if (ldlm_is_cancel_on_block(lock)) {
                         unlock_res_and_lock(lock);
                         ldlm_lock_cancel(lock);
                         instant_cancel = 1;
@@ -946,77 +1016,113 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, int flags, void *data)
                 lprocfs_counter_incr(lock->l_export->exp_nid_stats->nid_ldlm_stats,
                                      LDLM_CP_CALLBACK - LDLM_FIRST_OPC);
 
-        rc = ldlm_bl_and_cp_ast_tail(req, arg, lock, instant_cancel);
+       rc = ldlm_ast_fini(req, arg, lock, instant_cancel);
 
-        RETURN(rc);
+       RETURN(lvb_len < 0 ? lvb_len : rc);
 }
+EXPORT_SYMBOL(ldlm_server_completion_ast);
 
+/**
+ * Server side ->l_glimpse_ast handler for client locks.
+ *
+ * Sends glimpse AST to the client and waits for reply. Then updates
+ * lvbo with the result.
+ */
 int ldlm_server_glimpse_ast(struct ldlm_lock *lock, void *data)
 {
-        struct ldlm_resource  *res = lock->l_resource;
-        struct ldlm_request   *body;
-        struct ptlrpc_request *req;
-        int                    rc;
+       struct ldlm_cb_set_arg          *arg = data;
+       struct ldlm_request             *body;
+       struct ptlrpc_request           *req;
+       struct ldlm_cb_async_args       *ca;
+       int                              rc;
+       struct req_format               *req_fmt;
         ENTRY;
 
         LASSERT(lock != NULL);
 
+       if (arg->gl_desc != NULL)
+               /* There is a glimpse descriptor to pack */
+               req_fmt = &RQF_LDLM_GL_DESC_CALLBACK;
+       else
+               req_fmt = &RQF_LDLM_GL_CALLBACK;
+
         req = ptlrpc_request_alloc_pack(lock->l_export->exp_imp_reverse,
-                                        &RQF_LDLM_GL_CALLBACK,
-                                        LUSTRE_DLM_VERSION, LDLM_GL_CALLBACK);
+                                       req_fmt, LUSTRE_DLM_VERSION,
+                                       LDLM_GL_CALLBACK);
 
         if (req == NULL)
                 RETURN(-ENOMEM);
 
+       if (arg->gl_desc != NULL) {
+               /* copy the GL descriptor */
+               union ldlm_gl_desc      *desc;
+               desc = req_capsule_client_get(&req->rq_pill, &RMF_DLM_GL_DESC);
+               *desc = *arg->gl_desc;
+       }
+
         body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
         body->lock_handle[0] = lock->l_remote_handle;
         ldlm_lock2desc(lock, &body->lock_desc);
 
+       CLASSERT(sizeof(*ca) <= sizeof(req->rq_async_args));
+       ca = ptlrpc_req_async_args(req);
+       ca->ca_set_arg = arg;
+       ca->ca_lock = lock;
+
         /* server namespace, doesn't need lock */
         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER,
-                             lock->l_resource->lr_lvb_len);
-        res = lock->l_resource;
+                             ldlm_lvbo_size(lock));
         ptlrpc_request_set_replen(req);
 
-
         req->rq_send_state = LUSTRE_IMP_FULL;
         /* ptlrpc_request_alloc_pack already set timeout */
         if (AT_OFF)
                 req->rq_timeout = ldlm_get_rq_timeout();
 
+       lock->l_last_activity = cfs_time_current_sec();
+
+       req->rq_interpret_reply = ldlm_cb_interpret;
+
         if (lock->l_export && lock->l_export->exp_nid_stats &&
             lock->l_export->exp_nid_stats->nid_ldlm_stats)
                 lprocfs_counter_incr(lock->l_export->exp_nid_stats->nid_ldlm_stats,
                                      LDLM_GL_CALLBACK - LDLM_FIRST_OPC);
 
-        rc = ptlrpc_queue_wait(req);
-        /* Update the LVB from disk if the AST failed (this is a legal race)
-         *
-         * - Glimpse callback of local lock just return -ELDLM_NO_LOCK_DATA.
-         * - Glimpse callback of remote lock might return -ELDLM_NO_LOCK_DATA
-         *   when inode is cleared. LU-274
-         */
-        if (rc == -ELDLM_NO_LOCK_DATA) {
-                LDLM_DEBUG(lock, "lost race - client has a lock but no inode");
-                ldlm_res_lvbo_update(res, NULL, 1);
-        } else if (rc != 0) {
-                rc = ldlm_handle_ast_error(lock, req, rc, "glimpse");
-        } else {
-                rc = ldlm_res_lvbo_update(res, req, 1);
-        }
+       rc = ldlm_ast_fini(req, arg, lock, 0);
 
-        ptlrpc_req_finished(req);
-        if (rc == -ERESTART)
-                ldlm_reprocess_all(res);
+       RETURN(rc);
+}
+EXPORT_SYMBOL(ldlm_server_glimpse_ast);
 
-        RETURN(rc);
+int ldlm_glimpse_locks(struct ldlm_resource *res, cfs_list_t *gl_work_list)
+{
+       int     rc;
+       ENTRY;
+
+       rc = ldlm_run_ast_work(ldlm_res_to_ns(res), gl_work_list,
+                              LDLM_WORK_GL_AST);
+       if (rc == -ERESTART)
+               ldlm_reprocess_all(res);
+
+       RETURN(rc);
 }
+EXPORT_SYMBOL(ldlm_glimpse_locks);
 
-#ifdef __KERNEL__
-extern unsigned long long lu_time_stamp_get(void);
-#else
-#define lu_time_stamp_get() time(NULL)
-#endif
+/* return LDLM lock associated with a lock callback request */
+struct ldlm_lock *ldlm_request_lock(struct ptlrpc_request *req)
+{
+       struct ldlm_cb_async_args       *ca;
+       struct ldlm_lock                *lock;
+       ENTRY;
+
+       ca = ptlrpc_req_async_args(req);
+       lock = ca->ca_lock;
+       if (lock == NULL)
+               RETURN(ERR_PTR(-EFAULT));
+
+       RETURN(lock);
+}
+EXPORT_SYMBOL(ldlm_request_lock);
 
 static void ldlm_svc_get_eopc(const struct ldlm_request *dlm_req,
                        struct lprocfs_stats *srv_stats)
@@ -1052,9 +1158,9 @@ static void ldlm_svc_get_eopc(const struct ldlm_request *dlm_req,
         return;
 }
 
-/*
- * Main server-side entry point into LDLM. This is called by ptlrpc service
- * threads to carry out client lock enqueueing requests.
+/**
+ * Main server-side entry point into LDLM for enqueue. This is called by ptlrpc
+ * service threads to carry out client lock enqueueing requests.
  */
 int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
                          struct ptlrpc_request *req,
@@ -1062,7 +1168,7 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
                          const struct ldlm_callback_suite *cbs)
 {
         struct ldlm_reply *dlm_rep;
-        __u32 flags;
+       __u64 flags;
         ldlm_error_t err = ELDLM_OK;
         struct ldlm_lock *lock = NULL;
         void *cookie = NULL;
@@ -1072,13 +1178,12 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
         LDLM_DEBUG_NOLOCK("server-side enqueue handler START");
 
         ldlm_request_cancel(req, dlm_req, LDLM_ENQUEUE_CANCEL_OFF);
-        flags = dlm_req->lock_flags;
+       flags = ldlm_flags_from_wire(dlm_req->lock_flags);
 
         LASSERT(req->rq_export);
 
-        if (req->rq_rqbd->rqbd_service->srv_stats)
-                ldlm_svc_get_eopc(dlm_req,
-                                  req->rq_rqbd->rqbd_service->srv_stats);
+       if (ptlrpc_req2svc(req)->srv_stats != NULL)
+               ldlm_svc_get_eopc(dlm_req, ptlrpc_req2svc(req)->srv_stats);
 
         if (req->rq_export && req->rq_export->exp_nid_stats &&
             req->rq_export->exp_nid_stats->nid_ldlm_stats)
@@ -1101,7 +1206,7 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
                 GOTO(out, rc = -EFAULT);
         }
 
-        if (req->rq_export->exp_connect_flags & OBD_CONNECT_IBITS) {
+       if (exp_connect_flags(req->rq_export) & OBD_CONNECT_IBITS) {
                 if (unlikely(dlm_req->lock_desc.l_resource.lr_type ==
                              LDLM_PLAIN)) {
                         DEBUG_REQ(D_ERROR, req,
@@ -1122,7 +1227,7 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
 
         /* INODEBITS_INTEROP: Perform conversion from plain lock to
          * inodebits lock if client does not support them. */
-        if (!(req->rq_export->exp_connect_flags & OBD_CONNECT_IBITS) &&
+       if (!(exp_connect_flags(req->rq_export) & OBD_CONNECT_IBITS) &&
             (dlm_req->lock_desc.l_resource.lr_type == LDLM_PLAIN)) {
                 dlm_req->lock_desc.l_resource.lr_type = LDLM_IBITS;
                 dlm_req->lock_desc.l_policy_data.l_inodebits.bits =
@@ -1132,25 +1237,32 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
         }
 #endif
 
-        if (unlikely(flags & LDLM_FL_REPLAY)) {
+       if (unlikely((flags & LDLM_FL_REPLAY) ||
+                    (lustre_msg_get_flags(req->rq_reqmsg) & MSG_RESENT))) {
                 /* Find an existing lock in the per-export lock hash */
+               /* In the function below, .hs_keycmp resolves to
+                * ldlm_export_lock_keycmp() */
+               /* coverity[overrun-buffer-val] */
                 lock = cfs_hash_lookup(req->rq_export->exp_lock_hash,
                                        (void *)&dlm_req->lock_handle[0]);
                 if (lock != NULL) {
                         DEBUG_REQ(D_DLMTRACE, req, "found existing lock cookie "
                                   LPX64, lock->l_handle.h_cookie);
+                       flags |= LDLM_FL_RESENT;
                         GOTO(existing_lock, rc = 0);
-                }
+               }
         }
 
-        /* The lock's callback data might be set in the policy function */
-        lock = ldlm_lock_create(ns, &dlm_req->lock_desc.l_resource.lr_name,
-                                dlm_req->lock_desc.l_resource.lr_type,
-                                dlm_req->lock_desc.l_req_mode,
-                                cbs, NULL, 0);
-
-        if (!lock)
-                GOTO(out, rc = -ENOMEM);
+       /* The lock's callback data might be set in the policy function */
+       lock = ldlm_lock_create(ns, &dlm_req->lock_desc.l_resource.lr_name,
+                               dlm_req->lock_desc.l_resource.lr_type,
+                               dlm_req->lock_desc.l_req_mode,
+                               cbs, NULL, 0, LVB_T_NONE);
+       if (IS_ERR(lock)) {
+               rc = PTR_ERR(lock);
+               lock = NULL;
+               GOTO(out, rc);
+       }
 
         lock->l_last_activity = cfs_time_current_sec();
         lock->l_remote_handle = dlm_req->lock_handle[0];
@@ -1182,11 +1294,8 @@ existing_lock:
                 /* based on the assumption that lvb size never changes during
                  * resource life time otherwise it need resource->lr_lock's
                  * protection */
-                if (lock->l_resource->lr_lvb_len) {
-                        req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB,
-                                             RCL_SERVER,
-                                             lock->l_resource->lr_lvb_len);
-                }
+               req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB,
+                                    RCL_SERVER, ldlm_lvbo_size(lock));
 
                 if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_ENQUEUE_EXTENT_ERR))
                         GOTO(out, rc = -ENOMEM);
@@ -1204,12 +1313,15 @@ existing_lock:
         if (dlm_req->lock_desc.l_resource.lr_type == LDLM_EXTENT)
                 lock->l_req_extent = lock->l_policy_data.l_extent;
 
-        err = ldlm_lock_enqueue(ns, &lock, cookie, (int *)&flags);
-        if (err)
-                GOTO(out, err);
+       err = ldlm_lock_enqueue(ns, &lock, cookie, &flags);
+       if (err) {
+               if ((int)err < 0)
+                       rc = (int)err;
+               GOTO(out, err);
+       }
 
         dlm_rep = req_capsule_server_get(&req->rq_pill, &RMF_DLM_REP);
-        dlm_rep->lock_flags = flags;
+       dlm_rep->lock_flags = ldlm_flags_to_wire(flags);
 
         ldlm_lock2desc(lock, &dlm_rep->lock_desc);
         ldlm_lock2handle(lock, &dlm_rep->lock_handle);
@@ -1220,8 +1332,9 @@ existing_lock:
 
         /* Now take into account flags to be inherited from original lock
            request both in reply to client and in our own lock flags. */
-        dlm_rep->lock_flags |= dlm_req->lock_flags & LDLM_INHERIT_FLAGS;
-        lock->l_flags |= dlm_req->lock_flags & LDLM_INHERIT_FLAGS;
+       dlm_rep->lock_flags |= dlm_req->lock_flags & LDLM_FL_INHERIT_MASK;
+       lock->l_flags |= ldlm_flags_from_wire(dlm_req->lock_flags &
+                                             LDLM_FL_INHERIT_MASK);
 
         /* Don't move a pending lock onto the export if it has already been
          * disconnected due to eviction (bug 5683) or server umount (bug 24324).
@@ -1230,8 +1343,8 @@ existing_lock:
                      OBD_FAIL_CHECK(OBD_FAIL_LDLM_ENQUEUE_OLD_EXPORT))) {
                 LDLM_ERROR(lock, "lock on destroyed export %p", req->rq_export);
                 rc = -ENOTCONN;
-        } else if (lock->l_flags & LDLM_FL_AST_SENT) {
-                dlm_rep->lock_flags |= LDLM_FL_AST_SENT;
+       } else if (ldlm_is_ast_sent(lock)) {
+               dlm_rep->lock_flags |= ldlm_flags_to_wire(LDLM_FL_AST_SENT);
                 if (lock->l_granted_mode == lock->l_req_mode) {
                         /*
                          * Only cancel lock if it was granted, because it would
@@ -1253,7 +1366,7 @@ existing_lock:
         if ((dlm_req->lock_desc.l_resource.lr_type == LDLM_PLAIN ||
             dlm_req->lock_desc.l_resource.lr_type == LDLM_IBITS) &&
              req->rq_export->exp_libclient) {
-                if (unlikely(!(lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK) ||
+               if (unlikely(!ldlm_is_cancel_on_block(lock) ||
                              !(dlm_rep->lock_flags & LDLM_FL_CANCEL_ON_BLOCK))){
                         CERROR("Granting sync lock to libclient. "
                                "req fl %d, rep fl %d, lock fl "LPX64"\n",
@@ -1286,26 +1399,37 @@ existing_lock:
 
         /* The LOCK_CHANGED code in ldlm_lock_enqueue depends on this
          * ldlm_reprocess_all.  If this moves, revisit that code. -phil */
-        if (lock) {
-                LDLM_DEBUG(lock, "server-side enqueue handler, sending reply"
-                           "(err=%d, rc=%d)", err, rc);
-
-                if (rc == 0) {
-                        if (lock->l_resource->lr_lvb_len > 0) {
-                                /* MDT path won't handle lr_lvb_data, so
-                                 * lock/unlock better be contained in the
-                                 * if block */
-                                void *lvb;
-
-                                lvb = req_capsule_server_get(&req->rq_pill,
-                                                             &RMF_DLM_LVB);
-                                LASSERTF(lvb != NULL, "req %p, lock %p\n",
-                                         req, lock);
-                                lock_res(lock->l_resource);
-                                memcpy(lvb, lock->l_resource->lr_lvb_data,
-                                       lock->l_resource->lr_lvb_len);
-                                unlock_res(lock->l_resource);
-                        }
+       if (lock != NULL) {
+               LDLM_DEBUG(lock, "server-side enqueue handler, sending reply"
+                          "(err=%d, rc=%d)", err, rc);
+
+               if (rc == 0) {
+                       if (req_capsule_has_field(&req->rq_pill, &RMF_DLM_LVB,
+                                                 RCL_SERVER) &&
+                           ldlm_lvbo_size(lock) > 0) {
+                               void *buf;
+                               int buflen;
+
+                               buf = req_capsule_server_get(&req->rq_pill,
+                                                            &RMF_DLM_LVB);
+                               LASSERTF(buf != NULL, "req %p, lock %p\n",
+                                        req, lock);
+                               buflen = req_capsule_get_size(&req->rq_pill,
+                                               &RMF_DLM_LVB, RCL_SERVER);
+                               if (buflen > 0) {
+                                       buflen = ldlm_lvbo_fill(lock, buf,
+                                                               buflen);
+                                       if (buflen >= 0)
+                                               req_capsule_shrink(
+                                                       &req->rq_pill,
+                                                       &RMF_DLM_LVB,
+                                                       buflen, RCL_SERVER);
+                                       else
+                                               rc = buflen;
+                               } else {
+                                       rc = buflen;
+                               }
+                       }
                 } else {
                         lock_res_and_lock(lock);
                         ldlm_resource_unlink_lock(lock);
@@ -1324,7 +1448,11 @@ existing_lock:
 
         return rc;
 }
+EXPORT_SYMBOL(ldlm_handle_enqueue0);
 
+/**
+ * Old-style LDLM main entry point for server code enqueue.
+ */
 int ldlm_handle_enqueue(struct ptlrpc_request *req,
                         ldlm_completion_callback completion_callback,
                         ldlm_blocking_callback blocking_callback,
@@ -1347,7 +1475,11 @@ int ldlm_handle_enqueue(struct ptlrpc_request *req,
         }
         return rc;
 }
+EXPORT_SYMBOL(ldlm_handle_enqueue);
 
+/**
+ * Main LDLM entry point for server code to process lock conversion requests.
+ */
 int ldlm_handle_convert0(struct ptlrpc_request *req,
                          const struct ldlm_request *dlm_req)
 {
@@ -1370,7 +1502,7 @@ int ldlm_handle_convert0(struct ptlrpc_request *req,
 
         lock = ldlm_handle2lock(&dlm_req->lock_handle[0]);
         if (!lock) {
-                req->rq_status = EINVAL;
+               req->rq_status = LUSTRE_EINVAL;
         } else {
                 void *res = NULL;
 
@@ -1384,7 +1516,7 @@ int ldlm_handle_convert0(struct ptlrpc_request *req,
                                 LDLM_DEBUG(lock, "converted waiting lock");
                         req->rq_status = 0;
                 } else {
-                        req->rq_status = EDEADLOCK;
+                       req->rq_status = LUSTRE_EDEADLK;
                 }
         }
 
@@ -1398,7 +1530,12 @@ int ldlm_handle_convert0(struct ptlrpc_request *req,
 
         RETURN(0);
 }
+EXPORT_SYMBOL(ldlm_handle_convert0);
 
+/**
+ * Old-style main LDLM entry point for server code to process lock conversion
+ * requests.
+ */
 int ldlm_handle_convert(struct ptlrpc_request *req)
 {
         int rc;
@@ -1413,8 +1550,14 @@ int ldlm_handle_convert(struct ptlrpc_request *req)
         }
         return rc;
 }
+EXPORT_SYMBOL(ldlm_handle_convert);
 
-/* Cancel all the locks whos handles are packed into ldlm_request */
+/**
+ * Cancel all the locks whose handles are packed into ldlm_request
+ *
+ * Called by server code expecting such combined cancel activity
+ * requests.
+ */
 int ldlm_request_cancel(struct ptlrpc_request *req,
                         const struct ldlm_request *dlm_req, int first)
 {
@@ -1427,6 +1570,9 @@ int ldlm_request_cancel(struct ptlrpc_request *req,
         if (first >= count)
                 RETURN(0);
 
+       if (count == 1 && dlm_req->lock_handle[0].cookie == 0)
+               RETURN(0);
+
         /* There is no lock on the server at the replay time,
          * skip lock cancelling to make replay tests to pass. */
         if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY)
@@ -1447,6 +1593,9 @@ int ldlm_request_cancel(struct ptlrpc_request *req,
                 res = lock->l_resource;
                 done++;
 
+               /* This code is an optimization to only attempt lock
+                * granting on the resource (that could be CPU-expensive)
+                * after we are done cancelling lock in that resource. */
                 if (res != pres) {
                         if (pres != NULL) {
                                 ldlm_reprocess_all(pres);
@@ -1471,7 +1620,13 @@ int ldlm_request_cancel(struct ptlrpc_request *req,
         LDLM_DEBUG_NOLOCK("server-side cancel handler END");
         RETURN(done);
 }
+EXPORT_SYMBOL(ldlm_request_cancel);
 
+/**
+ * Main LDLM entry point for server code to cancel locks.
+ *
+ * Typically gets called from service handler on LDLM_CANCEL opc.
+ */
 int ldlm_handle_cancel(struct ptlrpc_request *req)
 {
         struct ldlm_request *dlm_req;
@@ -1494,11 +1649,18 @@ int ldlm_handle_cancel(struct ptlrpc_request *req)
                 RETURN(rc);
 
         if (!ldlm_request_cancel(req, dlm_req, 0))
-                req->rq_status = ESTALE;
+               req->rq_status = LUSTRE_ESTALE;
 
         RETURN(ptlrpc_reply(req));
 }
+EXPORT_SYMBOL(ldlm_handle_cancel);
+#endif /* HAVE_SERVER_SUPPORT */
 
+/**
+ * Callback handler for receiving incoming blocking ASTs.
+ *
+ * This can only happen on client side.
+ */
 void ldlm_handle_bl_callback(struct ldlm_namespace *ns,
                              struct ldlm_lock_desc *ld, struct ldlm_lock *lock)
 {
@@ -1508,10 +1670,10 @@ void ldlm_handle_bl_callback(struct ldlm_namespace *ns,
         LDLM_DEBUG(lock, "client blocking AST callback handler");
 
         lock_res_and_lock(lock);
-        lock->l_flags |= LDLM_FL_CBPENDING;
+       ldlm_set_cbpending(lock);
 
-        if (lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK)
-                lock->l_flags |= LDLM_FL_CANCEL;
+       if (ldlm_is_cancel_on_block(lock))
+               ldlm_set_cancel(lock);
 
         do_ast = (!lock->l_readers && !lock->l_writers);
         unlock_res_and_lock(lock);
@@ -1532,89 +1694,125 @@ void ldlm_handle_bl_callback(struct ldlm_namespace *ns,
         EXIT;
 }
 
+/**
+ * Callback handler for receiving incoming completion ASTs.
+ *
+ * This only can happen on client side.
+ */
 static void ldlm_handle_cp_callback(struct ptlrpc_request *req,
                                     struct ldlm_namespace *ns,
                                     struct ldlm_request *dlm_req,
                                     struct ldlm_lock *lock)
 {
-        CFS_LIST_HEAD(ast_list);
-        ENTRY;
-
-        LDLM_DEBUG(lock, "client completion callback handler START");
-
-        if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_BL_CB_RACE)) {
-                int to = cfs_time_seconds(1);
-                while (to > 0) {
-                        cfs_schedule_timeout_and_set_state(
-                                CFS_TASK_INTERRUPTIBLE, to);
-                        if (lock->l_granted_mode == lock->l_req_mode ||
-                            lock->l_destroyed)
-                                break;
-                }
-        }
-
-        lock_res_and_lock(lock);
-        if (lock->l_destroyed ||
-            lock->l_granted_mode == lock->l_req_mode) {
-                /* bug 11300: the lock has already been granted */
-                unlock_res_and_lock(lock);
-                LDLM_DEBUG(lock, "Double grant race happened");
-                LDLM_LOCK_RELEASE(lock);
-                EXIT;
-                return;
-        }
-
-        /* If we receive the completion AST before the actual enqueue returned,
-         * then we might need to switch lock modes, resources, or extents. */
-        if (dlm_req->lock_desc.l_granted_mode != lock->l_req_mode) {
-                lock->l_req_mode = dlm_req->lock_desc.l_granted_mode;
-                LDLM_DEBUG(lock, "completion AST, new lock mode");
-        }
-
-        if (lock->l_resource->lr_type != LDLM_PLAIN) {
-                ldlm_convert_policy_to_local(req->rq_export,
-                                          dlm_req->lock_desc.l_resource.lr_type,
-                                          &dlm_req->lock_desc.l_policy_data,
-                                          &lock->l_policy_data);
-                LDLM_DEBUG(lock, "completion AST, new policy data");
-        }
+       int lvb_len;
+       CFS_LIST_HEAD(ast_list);
+       int rc = 0;
+       ENTRY;
+
+       LDLM_DEBUG(lock, "client completion callback handler START");
+
+       if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_BL_CB_RACE)) {
+               int to = cfs_time_seconds(1);
+               while (to > 0) {
+                       schedule_timeout_and_set_state(
+                               TASK_INTERRUPTIBLE, to);
+                       if (lock->l_granted_mode == lock->l_req_mode ||
+                           ldlm_is_destroyed(lock))
+                               break;
+               }
+       }
+
+       lvb_len = req_capsule_get_size(&req->rq_pill, &RMF_DLM_LVB, RCL_CLIENT);
+       if (lvb_len < 0) {
+               LDLM_ERROR(lock, "Fail to get lvb_len, rc = %d", lvb_len);
+               GOTO(out, rc = lvb_len);
+       } else if (lvb_len > 0) {
+               if (lock->l_lvb_len > 0) {
+                       /* for extent lock, lvb contains ost_lvb{}. */
+                       LASSERT(lock->l_lvb_data != NULL);
+
+                       if (unlikely(lock->l_lvb_len < lvb_len)) {
+                               LDLM_ERROR(lock, "Replied LVB is larger than "
+                                          "expectation, expected = %d, "
+                                          "replied = %d",
+                                          lock->l_lvb_len, lvb_len);
+                               GOTO(out, rc = -EINVAL);
+                       }
+               } else if (ldlm_has_layout(lock)) { /* for layout lock, lvb has
+                                                    * variable length */
+                       void *lvb_data;
+
+                       OBD_ALLOC_LARGE(lvb_data, lvb_len);
+                       if (lvb_data == NULL) {
+                               LDLM_ERROR(lock, "No memory: %d.\n", lvb_len);
+                               GOTO(out, rc = -ENOMEM);
+                       }
+
+                       lock_res_and_lock(lock);
+                       LASSERT(lock->l_lvb_data == NULL);
+                       lock->l_lvb_type = LVB_T_LAYOUT;
+                       lock->l_lvb_data = lvb_data;
+                       lock->l_lvb_len = lvb_len;
+                       unlock_res_and_lock(lock);
+               }
+       }
+
+       lock_res_and_lock(lock);
+       if (ldlm_is_destroyed(lock) ||
+           lock->l_granted_mode == lock->l_req_mode) {
+               /* bug 11300: the lock has already been granted */
+               unlock_res_and_lock(lock);
+               LDLM_DEBUG(lock, "Double grant race happened");
+               GOTO(out, rc = 0);
+       }
+
+       /* If we receive the completion AST before the actual enqueue returned,
+        * then we might need to switch lock modes, resources, or extents. */
+       if (dlm_req->lock_desc.l_granted_mode != lock->l_req_mode) {
+               lock->l_req_mode = dlm_req->lock_desc.l_granted_mode;
+               LDLM_DEBUG(lock, "completion AST, new lock mode");
+       }
+
+       if (lock->l_resource->lr_type != LDLM_PLAIN) {
+               ldlm_convert_policy_to_local(req->rq_export,
+                                         dlm_req->lock_desc.l_resource.lr_type,
+                                         &dlm_req->lock_desc.l_policy_data,
+                                         &lock->l_policy_data);
+               LDLM_DEBUG(lock, "completion AST, new policy data");
+       }
 
         ldlm_resource_unlink_lock(lock);
         if (memcmp(&dlm_req->lock_desc.l_resource.lr_name,
                    &lock->l_resource->lr_name,
                    sizeof(lock->l_resource->lr_name)) != 0) {
                 unlock_res_and_lock(lock);
-                if (ldlm_lock_change_resource(ns, lock,
-                                &dlm_req->lock_desc.l_resource.lr_name) != 0) {
-                        LDLM_ERROR(lock, "Failed to allocate resource");
-                        LDLM_LOCK_RELEASE(lock);
-                        EXIT;
-                        return;
-                }
+               rc = ldlm_lock_change_resource(ns, lock,
+                               &dlm_req->lock_desc.l_resource.lr_name);
+               if (rc < 0) {
+                       LDLM_ERROR(lock, "Failed to allocate resource");
+                       GOTO(out, rc);
+               }
                 LDLM_DEBUG(lock, "completion AST, new resource");
                 CERROR("change resource!\n");
                 lock_res_and_lock(lock);
         }
 
         if (dlm_req->lock_flags & LDLM_FL_AST_SENT) {
-                /* BL_AST locks are not needed in lru.
-                 * let ldlm_cancel_lru() be fast. */
+               /* BL_AST locks are not needed in LRU.
+                * Let ldlm_cancel_lru() be fast. */
                 ldlm_lock_remove_from_lru(lock);
-                lock->l_flags |= LDLM_FL_CBPENDING | LDLM_FL_BL_AST;
+               lock->l_flags |= LDLM_FL_CBPENDING | LDLM_FL_BL_AST;
                 LDLM_DEBUG(lock, "completion AST includes blocking AST");
         }
 
-        if (lock->l_lvb_len) {
-                if (req_capsule_get_size(&req->rq_pill, &RMF_DLM_LVB,
-                                         RCL_CLIENT) < lock->l_lvb_len) {
-                        LDLM_ERROR(lock, "completion AST did not contain "
-                                   "expected LVB!");
-                } else {
-                        void *lvb = req_capsule_client_get(&req->rq_pill,
-                                                           &RMF_DLM_LVB);
-                        memcpy(lock->l_lvb_data, lvb, lock->l_lvb_len);
-                }
-        }
+       if (lock->l_lvb_len > 0) {
+               rc = ldlm_fill_lvb(lock, &req->rq_pill, RCL_CLIENT,
+                                  lock->l_lvb_data, lvb_len);
+               if (rc < 0) {
+                       unlock_res_and_lock(lock);
+                       GOTO(out, rc);
+               }
+       }
 
         ldlm_grant_lock(lock, &ast_list);
         unlock_res_and_lock(lock);
@@ -1629,10 +1827,25 @@ static void ldlm_handle_cp_callback(struct ptlrpc_request *req,
 
         LDLM_DEBUG_NOLOCK("client completion callback handler END (lock %p)",
                           lock);
-        LDLM_LOCK_RELEASE(lock);
-        EXIT;
+       GOTO(out, rc);
+
+out:
+       if (rc < 0) {
+               lock_res_and_lock(lock);
+               ldlm_set_failed(lock);
+               unlock_res_and_lock(lock);
+               wake_up(&lock->l_waitq);
+       }
+       LDLM_LOCK_RELEASE(lock);
 }
 
+/**
+ * Callback handler for receiving incoming glimpse ASTs.
+ *
+ * This only can happen on client side.  After handling the glimpse AST
+ * we also consider dropping the lock here if it is unused locally for a
+ * long time.
+ */
 static void ldlm_handle_gl_callback(struct ptlrpc_request *req,
                                     struct ldlm_namespace *ns,
                                     struct ldlm_request *dlm_req,
@@ -1686,46 +1899,48 @@ static int ldlm_callback_reply(struct ptlrpc_request *req, int rc)
 }
 
 #ifdef __KERNEL__
-static int __ldlm_bl_to_thread(struct ldlm_bl_work_item *blwi, int mode)
+static int __ldlm_bl_to_thread(struct ldlm_bl_work_item *blwi,
+                              ldlm_cancel_flags_t cancel_flags)
 {
-        struct ldlm_bl_pool *blp = ldlm_state->ldlm_bl_pool;
-        ENTRY;
+       struct ldlm_bl_pool *blp = ldlm_state->ldlm_bl_pool;
+       ENTRY;
 
-        cfs_spin_lock(&blp->blp_lock);
-        if (blwi->blwi_lock && blwi->blwi_lock->l_flags & LDLM_FL_DISCARD_DATA) {
-                /* add LDLM_FL_DISCARD_DATA requests to the priority list */
-                cfs_list_add_tail(&blwi->blwi_entry, &blp->blp_prio_list);
-        } else {
-                /* other blocking callbacks are added to the regular list */
-                cfs_list_add_tail(&blwi->blwi_entry, &blp->blp_list);
-        }
-        cfs_spin_unlock(&blp->blp_lock);
+       spin_lock(&blp->blp_lock);
+       if (blwi->blwi_lock &&
+           ldlm_is_discard_data(blwi->blwi_lock)) {
+               /* add LDLM_FL_DISCARD_DATA requests to the priority list */
+               cfs_list_add_tail(&blwi->blwi_entry, &blp->blp_prio_list);
+       } else {
+               /* other blocking callbacks are added to the regular list */
+               cfs_list_add_tail(&blwi->blwi_entry, &blp->blp_list);
+       }
+       spin_unlock(&blp->blp_lock);
 
-        cfs_waitq_signal(&blp->blp_waitq);
+       wake_up(&blp->blp_waitq);
 
-        /* can not use blwi->blwi_mode as blwi could be already freed in
-           LDLM_ASYNC mode */
-        if (mode == LDLM_SYNC)
-                cfs_wait_for_completion(&blwi->blwi_comp);
+       /* can not check blwi->blwi_flags as blwi could be already freed in
+          LCF_ASYNC mode */
+       if (!(cancel_flags & LCF_ASYNC))
+               wait_for_completion(&blwi->blwi_comp);
 
-        RETURN(0);
+       RETURN(0);
 }
 
 static inline void init_blwi(struct ldlm_bl_work_item *blwi,
-                             struct ldlm_namespace *ns,
-                             struct ldlm_lock_desc *ld,
-                             cfs_list_t *cancels, int count,
-                             struct ldlm_lock *lock,
-                             int mode)
+                            struct ldlm_namespace *ns,
+                            struct ldlm_lock_desc *ld,
+                            cfs_list_t *cancels, int count,
+                            struct ldlm_lock *lock,
+                            ldlm_cancel_flags_t cancel_flags)
 {
-        cfs_init_completion(&blwi->blwi_comp);
+       init_completion(&blwi->blwi_comp);
         CFS_INIT_LIST_HEAD(&blwi->blwi_head);
 
-        if (cfs_memory_pressure_get())
+       if (memory_pressure_get())
                 blwi->blwi_mem_pressure = 1;
 
         blwi->blwi_ns = ns;
-        blwi->blwi_mode = mode;
+       blwi->blwi_flags = cancel_flags;
         if (ld != NULL)
                 blwi->blwi_ld = *ld;
         if (count) {
@@ -1737,53 +1952,67 @@ static inline void init_blwi(struct ldlm_bl_work_item *blwi,
         }
 }
 
+/**
+ * Queues a list of locks \a cancels containing \a count locks
+ * for later processing by a blocking thread.  If \a count is zero,
+ * then the lock referenced as \a lock is queued instead.
+ *
+ * The blocking thread would then call ->l_blocking_ast callback in the lock.
+ * If list addition fails an error is returned and caller is supposed to
+ * call ->l_blocking_ast itself.
+ */
 static int ldlm_bl_to_thread(struct ldlm_namespace *ns,
-                             struct ldlm_lock_desc *ld, struct ldlm_lock *lock,
-                             cfs_list_t *cancels, int count, int mode)
+                            struct ldlm_lock_desc *ld,
+                            struct ldlm_lock *lock,
+                            cfs_list_t *cancels, int count,
+                            ldlm_cancel_flags_t cancel_flags)
 {
-        ENTRY;
+       ENTRY;
 
-        if (cancels && count == 0)
-                RETURN(0);
+       if (cancels && count == 0)
+               RETURN(0);
 
-        if (mode == LDLM_SYNC) {
-                /* if it is synchronous call do minimum mem alloc, as it could
-                 * be triggered from kernel shrinker
-                 */
-                struct ldlm_bl_work_item blwi;
-                memset(&blwi, 0, sizeof(blwi));
-                init_blwi(&blwi, ns, ld, cancels, count, lock, LDLM_SYNC);
-                RETURN(__ldlm_bl_to_thread(&blwi, LDLM_SYNC));
-        } else {
-                struct ldlm_bl_work_item *blwi;
-                OBD_ALLOC(blwi, sizeof(*blwi));
-                if (blwi == NULL)
-                        RETURN(-ENOMEM);
-                init_blwi(blwi, ns, ld, cancels, count, lock, LDLM_ASYNC);
+       if (cancel_flags & LCF_ASYNC) {
+               struct ldlm_bl_work_item *blwi;
 
-                RETURN(__ldlm_bl_to_thread(blwi, LDLM_ASYNC));
-        }
+               OBD_ALLOC(blwi, sizeof(*blwi));
+               if (blwi == NULL)
+                       RETURN(-ENOMEM);
+               init_blwi(blwi, ns, ld, cancels, count, lock, cancel_flags);
+
+               RETURN(__ldlm_bl_to_thread(blwi, cancel_flags));
+       } else {
+               /* if it is synchronous call do minimum mem alloc, as it could
+                * be triggered from kernel shrinker
+                */
+               struct ldlm_bl_work_item blwi;
+
+               memset(&blwi, 0, sizeof(blwi));
+               init_blwi(&blwi, ns, ld, cancels, count, lock, cancel_flags);
+               RETURN(__ldlm_bl_to_thread(&blwi, cancel_flags));
+       }
 }
 
 #endif
 
 int ldlm_bl_to_thread_lock(struct ldlm_namespace *ns, struct ldlm_lock_desc *ld,
-                           struct ldlm_lock *lock)
+                          struct ldlm_lock *lock)
 {
 #ifdef __KERNEL__
-        RETURN(ldlm_bl_to_thread(ns, ld, lock, NULL, 0, LDLM_ASYNC));
+       return ldlm_bl_to_thread(ns, ld, lock, NULL, 0, LCF_ASYNC);
 #else
-        RETURN(-ENOSYS);
+       return -ENOSYS;
 #endif
 }
 
 int ldlm_bl_to_thread_list(struct ldlm_namespace *ns, struct ldlm_lock_desc *ld,
-                           cfs_list_t *cancels, int count, int mode)
+                          cfs_list_t *cancels, int count,
+                          ldlm_cancel_flags_t cancel_flags)
 {
 #ifdef __KERNEL__
-        RETURN(ldlm_bl_to_thread(ns, ld, NULL, cancels, count, mode));
+       return ldlm_bl_to_thread(ns, ld, NULL, cancels, count, cancel_flags);
 #else
-        RETURN(-ENOSYS);
+       return -ENOSYS;
 #endif
 }
 
@@ -1820,7 +2049,8 @@ static int ldlm_handle_setinfo(struct ptlrpc_request *req)
 
         if (KEY_IS(KEY_HSM_COPYTOOL_SEND))
                 /* Pass it on to mdc (the "export" in this case) */
-                rc = obd_set_info_async(req->rq_export,
+                rc = obd_set_info_async(req->rq_svc_thread->t_env,
+                                        req->rq_export,
                                         sizeof(KEY_HSM_COPYTOOL_SEND),
                                         KEY_HSM_COPYTOOL_SEND,
                                         vallen, val, NULL);
@@ -1844,6 +2074,23 @@ static inline void ldlm_callback_errmsg(struct ptlrpc_request *req,
                 CWARN("Send reply failed, maybe cause bug 21636.\n");
 }
 
+static int ldlm_handle_qc_callback(struct ptlrpc_request *req)
+{
+       struct obd_quotactl *oqctl;
+       struct client_obd *cli = &req->rq_export->exp_obd->u.cli;
+
+       oqctl = req_capsule_client_get(&req->rq_pill, &RMF_OBD_QUOTACTL);
+       if (oqctl == NULL) {
+               CERROR("Can't unpack obd_quotactl\n");
+               RETURN(-EPROTO);
+       }
+
+       oqctl->qc_stat = ptlrpc_status_ntoh(oqctl->qc_stat);
+
+       cli->cl_qchk_stat = oqctl->qc_stat;
+       return 0;
+}
+
 /* TODO: handle requests in a similar way as MDT: see mdt_handle_common() */
 static int ldlm_callback_handler(struct ptlrpc_request *req)
 {
@@ -1874,51 +2121,28 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
         LASSERT(req->rq_export != NULL);
         LASSERT(req->rq_export->exp_obd != NULL);
 
-        switch (lustre_msg_get_opc(req->rq_reqmsg)) {
-        case LDLM_BL_CALLBACK:
-                if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_BL_CALLBACK))
-                        RETURN(0);
-                break;
-        case LDLM_CP_CALLBACK:
-                if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CP_CALLBACK))
-                        RETURN(0);
-                break;
-        case LDLM_GL_CALLBACK:
-                if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_GL_CALLBACK))
-                        RETURN(0);
-                break;
+       switch (lustre_msg_get_opc(req->rq_reqmsg)) {
+       case LDLM_BL_CALLBACK:
+               if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_BL_CALLBACK_NET))
+                       RETURN(0);
+               break;
+       case LDLM_CP_CALLBACK:
+               if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CP_CALLBACK_NET))
+                       RETURN(0);
+               break;
+       case LDLM_GL_CALLBACK:
+               if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_GL_CALLBACK_NET))
+                       RETURN(0);
+               break;
         case LDLM_SET_INFO:
                 rc = ldlm_handle_setinfo(req);
                 ldlm_callback_reply(req, rc);
                 RETURN(0);
-        case OBD_LOG_CANCEL: /* remove this eventually - for 1.4.0 compat */
-                CERROR("shouldn't be handling OBD_LOG_CANCEL on DLM thread\n");
-                req_capsule_set(&req->rq_pill, &RQF_LOG_CANCEL);
-                if (OBD_FAIL_CHECK(OBD_FAIL_OBD_LOG_CANCEL_NET))
-                        RETURN(0);
-                rc = llog_origin_handle_cancel(req);
-                if (OBD_FAIL_CHECK(OBD_FAIL_OBD_LOG_CANCEL_REP))
-                        RETURN(0);
-                ldlm_callback_reply(req, rc);
-                RETURN(0);
-        case OBD_QC_CALLBACK:
-                req_capsule_set(&req->rq_pill, &RQF_QC_CALLBACK);
-                if (OBD_FAIL_CHECK(OBD_FAIL_OBD_QC_CALLBACK_NET))
-                        RETURN(0);
-                rc = target_handle_qc_callback(req);
-                ldlm_callback_reply(req, rc);
-                RETURN(0);
-        case QUOTA_DQACQ:
-        case QUOTA_DQREL:
-                /* reply in handler */
-                req_capsule_set(&req->rq_pill, &RQF_MDS_QUOTA_DQACQ);
-                rc = target_handle_dqacq_callback(req);
-                RETURN(0);
         case LLOG_ORIGIN_HANDLE_CREATE:
                 req_capsule_set(&req->rq_pill, &RQF_LLOG_ORIGIN_HANDLE_CREATE);
                 if (OBD_FAIL_CHECK(OBD_FAIL_OBD_LOGD_NET))
                         RETURN(0);
-                rc = llog_origin_handle_create(req);
+               rc = llog_origin_handle_open(req);
                 ldlm_callback_reply(req, rc);
                 RETURN(0);
         case LLOG_ORIGIN_HANDLE_NEXT_BLOCK:
@@ -1943,6 +2167,13 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
                 rc = llog_origin_handle_close(req);
                 ldlm_callback_reply(req, rc);
                 RETURN(0);
+       case OBD_QC_CALLBACK:
+               req_capsule_set(&req->rq_pill, &RQF_QC_CALLBACK);
+               if (OBD_FAIL_CHECK(OBD_FAIL_OBD_QC_CALLBACK_NET))
+                       RETURN(0);
+               rc = ldlm_handle_qc_callback(req);
+               ldlm_callback_reply(req, rc);
+               RETURN(0);
         default:
                 CERROR("unknown opcode %u\n",
                        lustre_msg_get_opc(req->rq_reqmsg));
@@ -1967,7 +2198,7 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
          * which the server has already started a blocking callback on. */
         if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_BL_CB_RACE) &&
             lustre_msg_get_opc(req->rq_reqmsg) == LDLM_BL_CALLBACK) {
-                rc = ldlm_cli_cancel(&dlm_req->lock_handle[0]);
+               rc = ldlm_cli_cancel(&dlm_req->lock_handle[0], 0);
                 if (rc < 0)
                         CERROR("ldlm_cli_cancel: %d\n", rc);
         }
@@ -1982,21 +2213,21 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
                 RETURN(0);
         }
 
-        if ((lock->l_flags & LDLM_FL_FAIL_LOC) &&
+       if (ldlm_is_fail_loc(lock) &&
             lustre_msg_get_opc(req->rq_reqmsg) == LDLM_BL_CALLBACK)
                 OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 
         /* Copy hints/flags (e.g. LDLM_FL_DISCARD_DATA) from AST. */
         lock_res_and_lock(lock);
-        lock->l_flags |= (dlm_req->lock_flags & LDLM_AST_FLAGS);
+       lock->l_flags |= ldlm_flags_from_wire(dlm_req->lock_flags &
+                                             LDLM_FL_AST_MASK);
         if (lustre_msg_get_opc(req->rq_reqmsg) == LDLM_BL_CALLBACK) {
                 /* If somebody cancels lock and cache is already dropped,
                  * or lock is failed before cp_ast received on client,
                  * we can tell the server we have no lock. Otherwise, we
                  * should send cancel after dropping the cache. */
-                if (((lock->l_flags & LDLM_FL_CANCELING) &&
-                    (lock->l_flags & LDLM_FL_BL_DONE)) ||
-                    (lock->l_flags & LDLM_FL_FAILED)) {
+               if ((ldlm_is_canceling(lock) && ldlm_is_bl_done(lock)) ||
+                   ldlm_is_failed(lock)) {
                         LDLM_DEBUG(lock, "callback on lock "
                                    LPX64" - lock disappeared\n",
                                    dlm_req->lock_handle[0].cookie);
@@ -2007,10 +2238,10 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
                                              &dlm_req->lock_handle[0]);
                         RETURN(0);
                 }
-                /* BL_AST locks are not needed in lru.
-                 * let ldlm_cancel_lru() be fast. */
+               /* BL_AST locks are not needed in LRU.
+                * Let ldlm_cancel_lru() be fast. */
                 ldlm_lock_remove_from_lru(lock);
-                lock->l_flags |= LDLM_FL_BL_AST;
+               ldlm_set_bl_ast(lock);
         }
         unlock_res_and_lock(lock);
 
@@ -2027,7 +2258,7 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
         case LDLM_BL_CALLBACK:
                 CDEBUG(D_INODE, "blocking ast\n");
                 req_capsule_extend(&req->rq_pill, &RQF_LDLM_BL_CALLBACK);
-                if (!(lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK)) {
+               if (!ldlm_is_cancel_on_block(lock)) {
                         rc = ldlm_callback_reply(req, 0);
                         if (req->rq_no_reply || rc)
                                 ldlm_callback_errmsg(req, "Normal process", rc,
@@ -2054,6 +2285,12 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
         RETURN(0);
 }
 
+#ifdef HAVE_SERVER_SUPPORT
+/**
+ * Main handler for canceld thread.
+ *
+ * Separated into its own thread to avoid deadlocks.
+ */
 static int ldlm_cancel_handler(struct ptlrpc_request *req)
 {
         int rc;
@@ -2094,21 +2331,13 @@ static int ldlm_cancel_handler(struct ptlrpc_request *req)
         case LDLM_CANCEL:
                 req_capsule_set(&req->rq_pill, &RQF_LDLM_CANCEL);
                 CDEBUG(D_INODE, "cancel\n");
-                if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL))
-                        RETURN(0);
+               if (CFS_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_NET) ||
+                   CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_CANCEL_RESEND))
+                       RETURN(0);
                 rc = ldlm_handle_cancel(req);
                 if (rc)
                         break;
                 RETURN(0);
-        case OBD_LOG_CANCEL:
-                req_capsule_set(&req->rq_pill, &RQF_LOG_CANCEL);
-                if (OBD_FAIL_CHECK(OBD_FAIL_OBD_LOG_CANCEL_NET))
-                        RETURN(0);
-                rc = llog_origin_handle_cancel(req);
-                if (OBD_FAIL_CHECK(OBD_FAIL_OBD_LOG_CANCEL_REP))
-                        RETURN(0);
-                ldlm_callback_reply(req, rc);
-                RETURN(0);
         default:
                 CERROR("invalid opcode %d\n",
                        lustre_msg_get_opc(req->rq_reqmsg));
@@ -2170,7 +2399,7 @@ static int ldlm_cancel_hpreq_check(struct ptlrpc_request *req)
                 if (lock == NULL)
                         continue;
 
-                rc = !!(lock->l_flags & LDLM_FL_AST_SENT);
+               rc = ldlm_is_ast_sent(lock) ? 1 : 0;
                 if (rc)
                         LDLM_DEBUG(lock, "hpreq cancel lock");
                 LDLM_LOCK_PUT(lock);
@@ -2184,7 +2413,8 @@ static int ldlm_cancel_hpreq_check(struct ptlrpc_request *req)
 
 static struct ptlrpc_hpreq_ops ldlm_cancel_hpreq_ops = {
         .hpreq_lock_match = ldlm_cancel_hpreq_lock_match,
-        .hpreq_check      = ldlm_cancel_hpreq_check
+       .hpreq_check      = ldlm_cancel_hpreq_check,
+       .hpreq_fini       = NULL,
 };
 
 static int ldlm_hpreq_handler(struct ptlrpc_request *req)
@@ -2224,7 +2454,7 @@ int ldlm_revoke_lock_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
                 return 0;
         }
 
-        if (lock->l_flags & LDLM_FL_AST_SENT) {
+       if (ldlm_is_ast_sent(lock)) {
                 unlock_res_and_lock(lock);
                 return 0;
         }
@@ -2232,11 +2462,17 @@ int ldlm_revoke_lock_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
         LASSERT(lock->l_blocking_ast);
         LASSERT(!lock->l_blocking_lock);
 
-        lock->l_flags |= LDLM_FL_AST_SENT;
-        if (lock->l_export && lock->l_export->exp_lock_hash &&
-            !cfs_hlist_unhashed(&lock->l_exp_hash))
-                cfs_hash_del(lock->l_export->exp_lock_hash,
-                             &lock->l_remote_handle, &lock->l_exp_hash);
+       ldlm_set_ast_sent(lock);
+        if (lock->l_export && lock->l_export->exp_lock_hash) {
+               /* NB: it's safe to call cfs_hash_del() even lock isn't
+                * in exp_lock_hash. */
+               /* In the function below, .hs_keycmp resolves to
+                * ldlm_export_lock_keycmp() */
+               /* coverity[overrun-buffer-val] */
+               cfs_hash_del(lock->l_export->exp_lock_hash,
+                            &lock->l_remote_handle, &lock->l_exp_hash);
+       }
+
         cfs_list_add_tail(&lock->l_rk_ast, rpc_list);
         LDLM_LOCK_GET(lock);
 
@@ -2257,142 +2493,149 @@ void ldlm_revoke_export_locks(struct obd_export *exp)
 
         EXIT;
 }
+EXPORT_SYMBOL(ldlm_revoke_export_locks);
+#endif /* HAVE_SERVER_SUPPORT */
 
 #ifdef __KERNEL__
 static struct ldlm_bl_work_item *ldlm_bl_get_work(struct ldlm_bl_pool *blp)
 {
-        struct ldlm_bl_work_item *blwi = NULL;
-        static unsigned int num_bl = 0;
+       struct ldlm_bl_work_item *blwi = NULL;
+       static unsigned int num_bl = 0;
 
-        cfs_spin_lock(&blp->blp_lock);
-        /* process a request from the blp_list at least every blp_num_threads */
-        if (!cfs_list_empty(&blp->blp_list) &&
-            (cfs_list_empty(&blp->blp_prio_list) || num_bl == 0))
-                blwi = cfs_list_entry(blp->blp_list.next,
-                                      struct ldlm_bl_work_item, blwi_entry);
-        else
-                if (!cfs_list_empty(&blp->blp_prio_list))
-                        blwi = cfs_list_entry(blp->blp_prio_list.next,
-                                              struct ldlm_bl_work_item,
-                                              blwi_entry);
-
-        if (blwi) {
-                if (++num_bl >= cfs_atomic_read(&blp->blp_num_threads))
-                        num_bl = 0;
-                cfs_list_del(&blwi->blwi_entry);
-        }
-        cfs_spin_unlock(&blp->blp_lock);
+       spin_lock(&blp->blp_lock);
+       /* process a request from the blp_list at least every blp_num_threads */
+       if (!cfs_list_empty(&blp->blp_list) &&
+           (cfs_list_empty(&blp->blp_prio_list) || num_bl == 0))
+               blwi = cfs_list_entry(blp->blp_list.next,
+                                     struct ldlm_bl_work_item, blwi_entry);
+       else
+               if (!cfs_list_empty(&blp->blp_prio_list))
+                       blwi = cfs_list_entry(blp->blp_prio_list.next,
+                                             struct ldlm_bl_work_item,
+                                             blwi_entry);
+
+       if (blwi) {
+               if (++num_bl >= atomic_read(&blp->blp_num_threads))
+                       num_bl = 0;
+               cfs_list_del(&blwi->blwi_entry);
+       }
+       spin_unlock(&blp->blp_lock);
 
-        return blwi;
+       return blwi;
 }
 
 /* This only contains temporary data until the thread starts */
 struct ldlm_bl_thread_data {
-        char                    bltd_name[CFS_CURPROC_COMM_MAX];
-        struct ldlm_bl_pool     *bltd_blp;
-        cfs_completion_t        bltd_comp;
-        int                     bltd_num;
+       char                    bltd_name[CFS_CURPROC_COMM_MAX];
+       struct ldlm_bl_pool     *bltd_blp;
+       struct completion       bltd_comp;
+       int                     bltd_num;
 };
 
 static int ldlm_bl_thread_main(void *arg);
 
 static int ldlm_bl_thread_start(struct ldlm_bl_pool *blp)
 {
-        struct ldlm_bl_thread_data bltd = { .bltd_blp = blp };
-        int rc;
+       struct ldlm_bl_thread_data bltd = { .bltd_blp = blp };
+       struct task_struct *task;
 
-        cfs_init_completion(&bltd.bltd_comp);
-        rc = cfs_create_thread(ldlm_bl_thread_main, &bltd, 0);
-        if (rc < 0) {
-                CERROR("cannot start LDLM thread ldlm_bl_%02d: rc %d\n",
-                       cfs_atomic_read(&blp->blp_num_threads), rc);
-                return rc;
-        }
-        cfs_wait_for_completion(&bltd.bltd_comp);
+       init_completion(&bltd.bltd_comp);
+       bltd.bltd_num = atomic_read(&blp->blp_num_threads);
+       snprintf(bltd.bltd_name, sizeof(bltd.bltd_name) - 1,
+               "ldlm_bl_%02d", bltd.bltd_num);
+       task = kthread_run(ldlm_bl_thread_main, &bltd, bltd.bltd_name);
+       if (IS_ERR(task)) {
+               CERROR("cannot start LDLM thread ldlm_bl_%02d: rc %ld\n",
+                      atomic_read(&blp->blp_num_threads), PTR_ERR(task));
+               return PTR_ERR(task);
+       }
+       wait_for_completion(&bltd.bltd_comp);
 
-        return 0;
+       return 0;
 }
 
+/**
+ * Main blocking requests processing thread.
+ *
+ * Callers put locks into its queue by calling ldlm_bl_to_thread.
+ * This thread in the end ends up doing actual call to ->l_blocking_ast
+ * for queued locks.
+ */
 static int ldlm_bl_thread_main(void *arg)
 {
         struct ldlm_bl_pool *blp;
+       struct ldlm_bl_thread_data *bltd = arg;
         ENTRY;
 
-        {
-                struct ldlm_bl_thread_data *bltd = arg;
-
-                blp = bltd->bltd_blp;
+       blp = bltd->bltd_blp;
 
-                bltd->bltd_num =
-                        cfs_atomic_inc_return(&blp->blp_num_threads) - 1;
-                cfs_atomic_inc(&blp->blp_busy_threads);
+       atomic_inc(&blp->blp_num_threads);
+       atomic_inc(&blp->blp_busy_threads);
 
-                snprintf(bltd->bltd_name, sizeof(bltd->bltd_name) - 1,
-                        "ldlm_bl_%02d", bltd->bltd_num);
-                cfs_daemonize(bltd->bltd_name);
+       complete(&bltd->bltd_comp);
+       /* cannot use bltd after this, it is only on caller's stack */
 
-                cfs_complete(&bltd->bltd_comp);
-                /* cannot use bltd after this, it is only on caller's stack */
-        }
-
-        while (1) {
-                struct l_wait_info lwi = { 0 };
-                struct ldlm_bl_work_item *blwi = NULL;
-                int busy;
+       while (1) {
+               struct l_wait_info lwi = { 0 };
+               struct ldlm_bl_work_item *blwi = NULL;
+               int busy;
 
-                blwi = ldlm_bl_get_work(blp);
+               blwi = ldlm_bl_get_work(blp);
 
-                if (blwi == NULL) {
-                        cfs_atomic_dec(&blp->blp_busy_threads);
-                        l_wait_event_exclusive(blp->blp_waitq,
-                                         (blwi = ldlm_bl_get_work(blp)) != NULL,
-                                         &lwi);
-                        busy = cfs_atomic_inc_return(&blp->blp_busy_threads);
-                } else {
-                        busy = cfs_atomic_read(&blp->blp_busy_threads);
-                }
+               if (blwi == NULL) {
+                       atomic_dec(&blp->blp_busy_threads);
+                       l_wait_event_exclusive(blp->blp_waitq,
+                                        (blwi = ldlm_bl_get_work(blp)) != NULL,
+                                        &lwi);
+                       busy = atomic_inc_return(&blp->blp_busy_threads);
+               } else {
+                       busy = atomic_read(&blp->blp_busy_threads);
+               }
 
-                if (blwi->blwi_ns == NULL)
-                        /* added by ldlm_cleanup() */
-                        break;
+               if (blwi->blwi_ns == NULL)
+                       /* added by ldlm_cleanup() */
+                       break;
 
-                /* Not fatal if racy and have a few too many threads */
-                if (unlikely(busy < blp->blp_max_threads &&
-                             busy >= cfs_atomic_read(&blp->blp_num_threads) &&
-                             !blwi->blwi_mem_pressure))
-                        /* discard the return value, we tried */
-                        ldlm_bl_thread_start(blp);
+               /* Not fatal if racy and have a few too many threads */
+               if (unlikely(busy < blp->blp_max_threads &&
+                            busy >= atomic_read(&blp->blp_num_threads) &&
+                            !blwi->blwi_mem_pressure))
+                       /* discard the return value, we tried */
+                       ldlm_bl_thread_start(blp);
 
                 if (blwi->blwi_mem_pressure)
-                        cfs_memory_pressure_set();
+                       memory_pressure_set();
+
+               OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_PAUSE_CANCEL2, 4);
 
                 if (blwi->blwi_count) {
                         int count;
-                        /* The special case when we cancel locks in lru
+                       /* The special case when we cancel locks in LRU
                          * asynchronously, we pass the list of locks here.
                          * Thus locks are marked LDLM_FL_CANCELING, but NOT
                          * canceled locally yet. */
                         count = ldlm_cli_cancel_list_local(&blwi->blwi_head,
                                                            blwi->blwi_count,
                                                            LCF_BL_AST);
-                        ldlm_cli_cancel_list(&blwi->blwi_head, count, NULL, 0);
+                       ldlm_cli_cancel_list(&blwi->blwi_head, count, NULL,
+                                            blwi->blwi_flags);
                 } else {
                         ldlm_handle_bl_callback(blwi->blwi_ns, &blwi->blwi_ld,
                                                 blwi->blwi_lock);
                 }
                 if (blwi->blwi_mem_pressure)
-                        cfs_memory_pressure_clr();
+                       memory_pressure_clr();
 
-                if (blwi->blwi_mode == LDLM_ASYNC)
-                        OBD_FREE(blwi, sizeof(*blwi));
-                else
-                        cfs_complete(&blwi->blwi_comp);
-        }
+               if (blwi->blwi_flags & LCF_ASYNC)
+                       OBD_FREE(blwi, sizeof(*blwi));
+               else
+                       complete(&blwi->blwi_comp);
+       }
 
-        cfs_atomic_dec(&blp->blp_busy_threads);
-        cfs_atomic_dec(&blp->blp_num_threads);
-        cfs_complete(&blp->blp_comp);
-        RETURN(0);
+       atomic_dec(&blp->blp_busy_threads);
+       atomic_dec(&blp->blp_num_threads);
+       complete(&blp->blp_comp);
+       RETURN(0);
 }
 
 #endif
@@ -2404,21 +2647,22 @@ int ldlm_get_ref(void)
 {
         int rc = 0;
         ENTRY;
-        cfs_mutex_lock(&ldlm_ref_mutex);
+       mutex_lock(&ldlm_ref_mutex);
         if (++ldlm_refcount == 1) {
                 rc = ldlm_setup();
                 if (rc)
                         ldlm_refcount--;
         }
-        cfs_mutex_unlock(&ldlm_ref_mutex);
+       mutex_unlock(&ldlm_ref_mutex);
 
         RETURN(rc);
 }
+EXPORT_SYMBOL(ldlm_get_ref);
 
 void ldlm_put_ref(void)
 {
         ENTRY;
-        cfs_mutex_lock(&ldlm_ref_mutex);
+       mutex_lock(&ldlm_ref_mutex);
         if (ldlm_refcount == 1) {
                 int rc = ldlm_cleanup();
                 if (rc)
@@ -2428,10 +2672,11 @@ void ldlm_put_ref(void)
         } else {
                 ldlm_refcount--;
         }
-        cfs_mutex_unlock(&ldlm_ref_mutex);
+       mutex_unlock(&ldlm_ref_mutex);
 
         EXIT;
 }
+EXPORT_SYMBOL(ldlm_put_ref);
 
 /*
  * Export handle<->lock hash operations.
@@ -2503,6 +2748,7 @@ static cfs_hash_ops_t ldlm_export_lock_ops = {
 
 int ldlm_init_export(struct obd_export *exp)
 {
+       int rc;
         ENTRY;
 
         exp->exp_lock_hash =
@@ -2518,7 +2764,14 @@ int ldlm_init_export(struct obd_export *exp)
         if (!exp->exp_lock_hash)
                 RETURN(-ENOMEM);
 
+       rc = ldlm_init_flock_export(exp);
+       if (rc)
+               GOTO(err, rc);
+
         RETURN(0);
+err:
+       ldlm_destroy_export(exp);
+       RETURN(rc);
 }
 EXPORT_SYMBOL(ldlm_init_export);
 
@@ -2527,19 +2780,24 @@ void ldlm_destroy_export(struct obd_export *exp)
         ENTRY;
         cfs_hash_putref(exp->exp_lock_hash);
         exp->exp_lock_hash = NULL;
+
+       ldlm_destroy_flock_export(exp);
         EXIT;
 }
 EXPORT_SYMBOL(ldlm_destroy_export);
 
 static int ldlm_setup(void)
 {
-        struct ldlm_bl_pool *blp;
-        int rc = 0;
-        int ldlm_min_threads = LDLM_THREADS_AUTO_MIN;
-        int ldlm_max_threads = LDLM_THREADS_AUTO_MAX;
+       static struct ptlrpc_service_conf       conf;
+       struct ldlm_bl_pool                    *blp = NULL;
 #ifdef __KERNEL__
-        int i;
+# ifdef HAVE_SERVER_SUPPORT
+       struct task_struct *task;
+# endif
+       int i;
 #endif
+       int rc = 0;
+
         ENTRY;
 
         if (ldlm_state != NULL)
@@ -2552,126 +2810,154 @@ static int ldlm_setup(void)
 #ifdef LPROCFS
         rc = ldlm_proc_setup();
         if (rc != 0)
-                GOTO(out_free, rc);
+               GOTO(out, rc);
 #endif
 
-#ifdef __KERNEL__
-        if (ldlm_num_threads) {
-                /* If ldlm_num_threads is set, it is the min and the max. */
-                if (ldlm_num_threads > LDLM_THREADS_AUTO_MAX)
-                        ldlm_num_threads = LDLM_THREADS_AUTO_MAX;
-                if (ldlm_num_threads < LDLM_THREADS_AUTO_MIN)
-                        ldlm_num_threads = LDLM_THREADS_AUTO_MIN;
-                ldlm_min_threads = ldlm_max_threads = ldlm_num_threads;
-        }
+       memset(&conf, 0, sizeof(conf));
+       conf = (typeof(conf)) {
+               .psc_name               = "ldlm_cbd",
+               .psc_watchdog_factor    = 2,
+               .psc_buf                = {
+                       .bc_nbufs               = LDLM_CLIENT_NBUFS,
+                       .bc_buf_size            = LDLM_BUFSIZE,
+                       .bc_req_max_size        = LDLM_MAXREQSIZE,
+                       .bc_rep_max_size        = LDLM_MAXREPSIZE,
+                       .bc_req_portal          = LDLM_CB_REQUEST_PORTAL,
+                       .bc_rep_portal          = LDLM_CB_REPLY_PORTAL,
+               },
+               .psc_thr                = {
+                       .tc_thr_name            = "ldlm_cb",
+                       .tc_thr_factor          = LDLM_THR_FACTOR,
+                       .tc_nthrs_init          = LDLM_NTHRS_INIT,
+                       .tc_nthrs_base          = LDLM_NTHRS_BASE,
+                       .tc_nthrs_max           = LDLM_NTHRS_MAX,
+                       .tc_nthrs_user          = ldlm_num_threads,
+                       .tc_cpu_affinity        = 1,
+                       .tc_ctx_tags            = LCT_MD_THREAD | LCT_DT_THREAD,
+               },
+               .psc_cpt                = {
+                       .cc_pattern             = ldlm_cpts,
+               },
+               .psc_ops                = {
+                       .so_req_handler         = ldlm_callback_handler,
+               },
+       };
+       ldlm_state->ldlm_cb_service = \
+                       ptlrpc_register_service(&conf, ldlm_svc_proc_dir);
+       if (IS_ERR(ldlm_state->ldlm_cb_service)) {
+               CERROR("failed to start service\n");
+               rc = PTR_ERR(ldlm_state->ldlm_cb_service);
+               ldlm_state->ldlm_cb_service = NULL;
+               GOTO(out, rc);
+       }
+
+#ifdef HAVE_SERVER_SUPPORT
+       memset(&conf, 0, sizeof(conf));
+       conf = (typeof(conf)) {
+               .psc_name               = "ldlm_canceld",
+               .psc_watchdog_factor    = 6,
+               .psc_buf                = {
+                       .bc_nbufs               = LDLM_SERVER_NBUFS,
+                       .bc_buf_size            = LDLM_BUFSIZE,
+                       .bc_req_max_size        = LDLM_MAXREQSIZE,
+                       .bc_rep_max_size        = LDLM_MAXREPSIZE,
+                       .bc_req_portal          = LDLM_CANCEL_REQUEST_PORTAL,
+                       .bc_rep_portal          = LDLM_CANCEL_REPLY_PORTAL,
+
+               },
+               .psc_thr                = {
+                       .tc_thr_name            = "ldlm_cn",
+                       .tc_thr_factor          = LDLM_THR_FACTOR,
+                       .tc_nthrs_init          = LDLM_NTHRS_INIT,
+                       .tc_nthrs_base          = LDLM_NTHRS_BASE,
+                       .tc_nthrs_max           = LDLM_NTHRS_MAX,
+                       .tc_nthrs_user          = ldlm_num_threads,
+                       .tc_cpu_affinity        = 1,
+                       .tc_ctx_tags            = LCT_MD_THREAD | \
+                                                 LCT_DT_THREAD | \
+                                                 LCT_CL_THREAD,
+               },
+               .psc_cpt                = {
+                       .cc_pattern             = ldlm_cpts,
+               },
+               .psc_ops                = {
+                       .so_req_handler         = ldlm_cancel_handler,
+                       .so_hpreq_handler       = ldlm_hpreq_handler,
+               },
+       };
+       ldlm_state->ldlm_cancel_service = \
+                       ptlrpc_register_service(&conf, ldlm_svc_proc_dir);
+       if (IS_ERR(ldlm_state->ldlm_cancel_service)) {
+               CERROR("failed to start service\n");
+               rc = PTR_ERR(ldlm_state->ldlm_cancel_service);
+               ldlm_state->ldlm_cancel_service = NULL;
+               GOTO(out, rc);
+       }
 #endif
 
-        ldlm_state->ldlm_cb_service =
-                ptlrpc_init_svc(LDLM_NBUFS, LDLM_BUFSIZE, LDLM_MAXREQSIZE,
-                                LDLM_MAXREPSIZE, LDLM_CB_REQUEST_PORTAL,
-                                LDLM_CB_REPLY_PORTAL, 2,
-                                ldlm_callback_handler, "ldlm_cbd",
-                                ldlm_svc_proc_dir, NULL,
-                                ldlm_min_threads, ldlm_max_threads,
-                                "ldlm_cb",
-                                LCT_MD_THREAD|LCT_DT_THREAD, NULL);
-
-        if (!ldlm_state->ldlm_cb_service) {
-                CERROR("failed to start service\n");
-                GOTO(out_proc, rc = -ENOMEM);
-        }
-
-        ldlm_state->ldlm_cancel_service =
-                ptlrpc_init_svc(LDLM_NBUFS, LDLM_BUFSIZE, LDLM_MAXREQSIZE,
-                                LDLM_MAXREPSIZE, LDLM_CANCEL_REQUEST_PORTAL,
-                                LDLM_CANCEL_REPLY_PORTAL, 6,
-                                ldlm_cancel_handler, "ldlm_canceld",
-                                ldlm_svc_proc_dir, NULL,
-                                ldlm_min_threads, ldlm_max_threads,
-                                "ldlm_cn",
-                                LCT_MD_THREAD|LCT_DT_THREAD|LCT_CL_THREAD,
-                                ldlm_hpreq_handler);
-
-        if (!ldlm_state->ldlm_cancel_service) {
-                CERROR("failed to start service\n");
-                GOTO(out_proc, rc = -ENOMEM);
-        }
-
-        OBD_ALLOC(blp, sizeof(*blp));
-        if (blp == NULL)
-                GOTO(out_proc, rc = -ENOMEM);
-        ldlm_state->ldlm_bl_pool = blp;
-
-        cfs_spin_lock_init(&blp->blp_lock);
-        CFS_INIT_LIST_HEAD(&blp->blp_list);
-        CFS_INIT_LIST_HEAD(&blp->blp_prio_list);
-        cfs_waitq_init(&blp->blp_waitq);
-        cfs_atomic_set(&blp->blp_num_threads, 0);
-        cfs_atomic_set(&blp->blp_busy_threads, 0);
-        blp->blp_min_threads = ldlm_min_threads;
-        blp->blp_max_threads = ldlm_max_threads;
-
-#ifdef __KERNEL__
-        for (i = 0; i < blp->blp_min_threads; i++) {
-                rc = ldlm_bl_thread_start(blp);
-                if (rc < 0)
-                        GOTO(out_thread, rc);
-        }
-
-        rc = ptlrpc_start_threads(ldlm_state->ldlm_cancel_service);
-        if (rc)
-                GOTO(out_thread, rc);
-
-        rc = ptlrpc_start_threads(ldlm_state->ldlm_cb_service);
-        if (rc)
-                GOTO(out_thread, rc);
-
-        CFS_INIT_LIST_HEAD(&expired_lock_thread.elt_expired_locks);
-        expired_lock_thread.elt_state = ELT_STOPPED;
-        cfs_waitq_init(&expired_lock_thread.elt_waitq);
-
-        CFS_INIT_LIST_HEAD(&waiting_locks_list);
-        cfs_spin_lock_init(&waiting_locks_spinlock);
-        cfs_timer_init(&waiting_locks_timer, waiting_locks_callback, 0);
-
-        rc = cfs_create_thread(expired_lock_main, NULL, CFS_DAEMON_FLAGS);
-        if (rc < 0) {
-                CERROR("Cannot start ldlm expired-lock thread: %d\n", rc);
-                GOTO(out_thread, rc);
-        }
-
-        cfs_wait_event(expired_lock_thread.elt_waitq,
-                       expired_lock_thread.elt_state == ELT_READY);
-#endif
+       OBD_ALLOC(blp, sizeof(*blp));
+       if (blp == NULL)
+               GOTO(out, rc = -ENOMEM);
+       ldlm_state->ldlm_bl_pool = blp;
 
-#ifdef __KERNEL__
-        rc = ldlm_pools_init();
-        if (rc)
-                GOTO(out_thread, rc);
-#endif
-        RETURN(0);
+       spin_lock_init(&blp->blp_lock);
+       CFS_INIT_LIST_HEAD(&blp->blp_list);
+       CFS_INIT_LIST_HEAD(&blp->blp_prio_list);
+       init_waitqueue_head(&blp->blp_waitq);
+       atomic_set(&blp->blp_num_threads, 0);
+       atomic_set(&blp->blp_busy_threads, 0);
 
 #ifdef __KERNEL__
- out_thread:
-        ptlrpc_unregister_service(ldlm_state->ldlm_cancel_service);
-        ptlrpc_unregister_service(ldlm_state->ldlm_cb_service);
+       if (ldlm_num_threads == 0) {
+               blp->blp_min_threads = LDLM_NTHRS_INIT;
+               blp->blp_max_threads = LDLM_NTHRS_MAX;
+       } else {
+               blp->blp_min_threads = blp->blp_max_threads = \
+                       min_t(int, LDLM_NTHRS_MAX, max_t(int, LDLM_NTHRS_INIT,
+                                                        ldlm_num_threads));
+       }
+
+       for (i = 0; i < blp->blp_min_threads; i++) {
+               rc = ldlm_bl_thread_start(blp);
+               if (rc < 0)
+                       GOTO(out, rc);
+       }
+
+# ifdef HAVE_SERVER_SUPPORT
+       CFS_INIT_LIST_HEAD(&expired_lock_thread.elt_expired_locks);
+       expired_lock_thread.elt_state = ELT_STOPPED;
+       init_waitqueue_head(&expired_lock_thread.elt_waitq);
+
+       CFS_INIT_LIST_HEAD(&waiting_locks_list);
+       spin_lock_init(&waiting_locks_spinlock);
+       cfs_timer_init(&waiting_locks_timer, waiting_locks_callback, 0);
+
+       task = kthread_run(expired_lock_main, NULL, "ldlm_elt");
+       if (IS_ERR(task)) {
+               rc = PTR_ERR(task);
+               CERROR("Cannot start ldlm expired-lock thread: %d\n", rc);
+               GOTO(out, rc);
+       }
+
+       wait_event(expired_lock_thread.elt_waitq,
+                      expired_lock_thread.elt_state == ELT_READY);
+# endif /* HAVE_SERVER_SUPPORT */
+
+       rc = ldlm_pools_init();
+       if (rc) {
+               CERROR("Failed to initialize LDLM pools: %d\n", rc);
+               GOTO(out, rc);
+       }
 #endif
+       RETURN(0);
 
- out_proc:
-#ifdef LPROCFS
-        ldlm_proc_cleanup();
- out_free:
-#endif
-        OBD_FREE(ldlm_state, sizeof(*ldlm_state));
-        ldlm_state = NULL;
-        return rc;
+ out:
+       ldlm_cleanup();
+       RETURN(rc);
 }
 
 static int ldlm_cleanup(void)
 {
-#ifdef __KERNEL__
-        struct ldlm_bl_pool *blp = ldlm_state->ldlm_bl_pool;
-#endif
         ENTRY;
 
         if (!cfs_list_empty(ldlm_namespace_list(LDLM_NAMESPACE_SERVER)) ||
@@ -2684,35 +2970,46 @@ static int ldlm_cleanup(void)
 
 #ifdef __KERNEL__
         ldlm_pools_fini();
-#endif
 
-#ifdef __KERNEL__
-        while (cfs_atomic_read(&blp->blp_num_threads) > 0) {
-                struct ldlm_bl_work_item blwi = { .blwi_ns = NULL };
+       if (ldlm_state->ldlm_bl_pool != NULL) {
+               struct ldlm_bl_pool *blp = ldlm_state->ldlm_bl_pool;
 
-                cfs_init_completion(&blp->blp_comp);
+               while (atomic_read(&blp->blp_num_threads) > 0) {
+                       struct ldlm_bl_work_item blwi = { .blwi_ns = NULL };
 
-                cfs_spin_lock(&blp->blp_lock);
-                cfs_list_add_tail(&blwi.blwi_entry, &blp->blp_list);
-                cfs_waitq_signal(&blp->blp_waitq);
-                cfs_spin_unlock(&blp->blp_lock);
+                       init_completion(&blp->blp_comp);
 
-                cfs_wait_for_completion(&blp->blp_comp);
-        }
-        OBD_FREE(blp, sizeof(*blp));
+                       spin_lock(&blp->blp_lock);
+                       cfs_list_add_tail(&blwi.blwi_entry, &blp->blp_list);
+                       wake_up(&blp->blp_waitq);
+                       spin_unlock(&blp->blp_lock);
 
-        ptlrpc_unregister_service(ldlm_state->ldlm_cb_service);
-        ptlrpc_unregister_service(ldlm_state->ldlm_cancel_service);
-        ldlm_proc_cleanup();
+                       wait_for_completion(&blp->blp_comp);
+               }
 
-        expired_lock_thread.elt_state = ELT_TERMINATE;
-        cfs_waitq_signal(&expired_lock_thread.elt_waitq);
-        cfs_wait_event(expired_lock_thread.elt_waitq,
-                       expired_lock_thread.elt_state == ELT_STOPPED);
-#else
-        ptlrpc_unregister_service(ldlm_state->ldlm_cb_service);
-        ptlrpc_unregister_service(ldlm_state->ldlm_cancel_service);
-#endif
+               OBD_FREE(blp, sizeof(*blp));
+       }
+#endif /* __KERNEL__ */
+
+       if (ldlm_state->ldlm_cb_service != NULL)
+               ptlrpc_unregister_service(ldlm_state->ldlm_cb_service);
+# ifdef HAVE_SERVER_SUPPORT
+       if (ldlm_state->ldlm_cancel_service != NULL)
+               ptlrpc_unregister_service(ldlm_state->ldlm_cancel_service);
+# endif
+
+#ifdef __KERNEL__
+       ldlm_proc_cleanup();
+
+# ifdef HAVE_SERVER_SUPPORT
+       if (expired_lock_thread.elt_state != ELT_STOPPED) {
+               expired_lock_thread.elt_state = ELT_TERMINATE;
+               wake_up(&expired_lock_thread.elt_waitq);
+               wait_event(expired_lock_thread.elt_waitq,
+                              expired_lock_thread.elt_state == ELT_STOPPED);
+       }
+# endif
+#endif /* __KERNEL__ */
 
         OBD_FREE(ldlm_state, sizeof(*ldlm_state));
         ldlm_state = NULL;
@@ -2722,29 +3019,29 @@ static int ldlm_cleanup(void)
 
 int ldlm_init(void)
 {
-        cfs_mutex_init(&ldlm_ref_mutex);
-        cfs_mutex_init(ldlm_namespace_lock(LDLM_NAMESPACE_SERVER));
-        cfs_mutex_init(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
-        ldlm_resource_slab = cfs_mem_cache_create("ldlm_resources",
-                                               sizeof(struct ldlm_resource), 0,
-                                               CFS_SLAB_HWCACHE_ALIGN);
-        if (ldlm_resource_slab == NULL)
-                return -ENOMEM;
-
-        ldlm_lock_slab = cfs_mem_cache_create("ldlm_locks",
-                              sizeof(struct ldlm_lock), 0,
-                              CFS_SLAB_HWCACHE_ALIGN | CFS_SLAB_DESTROY_BY_RCU);
-        if (ldlm_lock_slab == NULL) {
-                cfs_mem_cache_destroy(ldlm_resource_slab);
-                return -ENOMEM;
-        }
-
-        ldlm_interval_slab = cfs_mem_cache_create("interval_node",
+       mutex_init(&ldlm_ref_mutex);
+       mutex_init(ldlm_namespace_lock(LDLM_NAMESPACE_SERVER));
+       mutex_init(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
+       ldlm_resource_slab = kmem_cache_create("ldlm_resources",
+                                              sizeof(struct ldlm_resource), 0,
+                                              SLAB_HWCACHE_ALIGN, NULL);
+       if (ldlm_resource_slab == NULL)
+               return -ENOMEM;
+
+       ldlm_lock_slab = kmem_cache_create("ldlm_locks",
+                             sizeof(struct ldlm_lock), 0,
+                             SLAB_HWCACHE_ALIGN | SLAB_DESTROY_BY_RCU, NULL);
+       if (ldlm_lock_slab == NULL) {
+               kmem_cache_destroy(ldlm_resource_slab);
+               return -ENOMEM;
+       }
+
+       ldlm_interval_slab = kmem_cache_create("interval_node",
                                         sizeof(struct ldlm_interval),
-                                        0, CFS_SLAB_HWCACHE_ALIGN);
+                                       0, SLAB_HWCACHE_ALIGN, NULL);
         if (ldlm_interval_slab == NULL) {
-                cfs_mem_cache_destroy(ldlm_resource_slab);
-                cfs_mem_cache_destroy(ldlm_lock_slab);
+               kmem_cache_destroy(ldlm_resource_slab);
+               kmem_cache_destroy(ldlm_lock_slab);
                 return -ENOMEM;
         }
 #if LUSTRE_TRACKS_LOCK_EXP_REFS
@@ -2755,122 +3052,15 @@ int ldlm_init(void)
 
 void ldlm_exit(void)
 {
-        int rc;
-        if (ldlm_refcount)
-                CERROR("ldlm_refcount is %d in ldlm_exit!\n", ldlm_refcount);
-        rc = cfs_mem_cache_destroy(ldlm_resource_slab);
-        LASSERTF(rc == 0, "couldn't free ldlm resource slab\n");
+       if (ldlm_refcount)
+               CERROR("ldlm_refcount is %d in ldlm_exit!\n", ldlm_refcount);
+       kmem_cache_destroy(ldlm_resource_slab);
 #ifdef __KERNEL__
-        /* ldlm_lock_put() use RCU to call ldlm_lock_free, so need call
-         * synchronize_rcu() to wait a grace period elapsed, so that
-         * ldlm_lock_free() get a chance to be called. */
-        synchronize_rcu();
+       /* ldlm_lock_put() use RCU to call ldlm_lock_free, so need call
+        * synchronize_rcu() to wait a grace period elapsed, so that
+        * ldlm_lock_free() get a chance to be called. */
+       synchronize_rcu();
 #endif
-        rc = cfs_mem_cache_destroy(ldlm_lock_slab);
-        LASSERTF(rc == 0, "couldn't free ldlm lock slab\n");
-        rc = cfs_mem_cache_destroy(ldlm_interval_slab);
-        LASSERTF(rc == 0, "couldn't free interval node slab\n");
-}
-
-/* ldlm_extent.c */
-EXPORT_SYMBOL(ldlm_extent_shift_kms);
-
-/* ldlm_lock.c */
-EXPORT_SYMBOL(ldlm_get_processing_policy);
-EXPORT_SYMBOL(ldlm_lock2desc);
-EXPORT_SYMBOL(ldlm_register_intent);
-EXPORT_SYMBOL(ldlm_lockname);
-EXPORT_SYMBOL(ldlm_typename);
-EXPORT_SYMBOL(ldlm_lock2handle);
-EXPORT_SYMBOL(__ldlm_handle2lock);
-EXPORT_SYMBOL(ldlm_lock_get);
-EXPORT_SYMBOL(ldlm_lock_put);
-EXPORT_SYMBOL(ldlm_lock_match);
-EXPORT_SYMBOL(ldlm_lock_cancel);
-EXPORT_SYMBOL(ldlm_lock_addref);
-EXPORT_SYMBOL(ldlm_lock_addref_try);
-EXPORT_SYMBOL(ldlm_lock_decref);
-EXPORT_SYMBOL(ldlm_lock_decref_and_cancel);
-EXPORT_SYMBOL(ldlm_lock_change_resource);
-EXPORT_SYMBOL(ldlm_it2str);
-EXPORT_SYMBOL(ldlm_lock_dump);
-EXPORT_SYMBOL(ldlm_lock_dump_handle);
-EXPORT_SYMBOL(ldlm_reprocess_all_ns);
-EXPORT_SYMBOL(ldlm_lock_allow_match_locked);
-EXPORT_SYMBOL(ldlm_lock_allow_match);
-EXPORT_SYMBOL(ldlm_lock_downgrade);
-EXPORT_SYMBOL(ldlm_lock_convert);
-
-/* ldlm_request.c */
-EXPORT_SYMBOL(ldlm_completion_ast_async);
-EXPORT_SYMBOL(ldlm_blocking_ast_nocheck);
-EXPORT_SYMBOL(ldlm_completion_ast);
-EXPORT_SYMBOL(ldlm_blocking_ast);
-EXPORT_SYMBOL(ldlm_glimpse_ast);
-EXPORT_SYMBOL(ldlm_expired_completion_wait);
-EXPORT_SYMBOL(ldlm_prep_enqueue_req);
-EXPORT_SYMBOL(ldlm_prep_elc_req);
-EXPORT_SYMBOL(ldlm_cli_convert);
-EXPORT_SYMBOL(ldlm_cli_enqueue);
-EXPORT_SYMBOL(ldlm_cli_enqueue_fini);
-EXPORT_SYMBOL(ldlm_cli_enqueue_local);
-EXPORT_SYMBOL(ldlm_cli_cancel);
-EXPORT_SYMBOL(ldlm_cli_cancel_unused);
-EXPORT_SYMBOL(ldlm_cli_cancel_unused_resource);
-EXPORT_SYMBOL(ldlm_cli_cancel_req);
-EXPORT_SYMBOL(ldlm_replay_locks);
-EXPORT_SYMBOL(ldlm_resource_foreach);
-EXPORT_SYMBOL(ldlm_namespace_foreach);
-EXPORT_SYMBOL(ldlm_resource_iterate);
-EXPORT_SYMBOL(ldlm_cancel_resource_local);
-EXPORT_SYMBOL(ldlm_cli_cancel_list_local);
-EXPORT_SYMBOL(ldlm_cli_cancel_list);
-
-/* ldlm_lockd.c */
-EXPORT_SYMBOL(ldlm_server_blocking_ast);
-EXPORT_SYMBOL(ldlm_server_completion_ast);
-EXPORT_SYMBOL(ldlm_server_glimpse_ast);
-EXPORT_SYMBOL(ldlm_handle_enqueue);
-EXPORT_SYMBOL(ldlm_handle_enqueue0);
-EXPORT_SYMBOL(ldlm_handle_cancel);
-EXPORT_SYMBOL(ldlm_request_cancel);
-EXPORT_SYMBOL(ldlm_handle_convert);
-EXPORT_SYMBOL(ldlm_handle_convert0);
-EXPORT_SYMBOL(ldlm_del_waiting_lock);
-EXPORT_SYMBOL(ldlm_get_ref);
-EXPORT_SYMBOL(ldlm_put_ref);
-EXPORT_SYMBOL(ldlm_refresh_waiting_lock);
-EXPORT_SYMBOL(ldlm_revoke_export_locks);
-
-/* ldlm_resource.c */
-EXPORT_SYMBOL(ldlm_namespace_new);
-EXPORT_SYMBOL(ldlm_namespace_cleanup);
-EXPORT_SYMBOL(ldlm_namespace_free);
-EXPORT_SYMBOL(ldlm_namespace_dump);
-EXPORT_SYMBOL(ldlm_dump_all_namespaces);
-EXPORT_SYMBOL(ldlm_resource_get);
-EXPORT_SYMBOL(ldlm_resource_putref);
-EXPORT_SYMBOL(ldlm_resource_unlink_lock);
-
-/* ldlm_lib.c */
-EXPORT_SYMBOL(client_import_add_conn);
-EXPORT_SYMBOL(client_import_del_conn);
-EXPORT_SYMBOL(client_obd_setup);
-EXPORT_SYMBOL(client_obd_cleanup);
-EXPORT_SYMBOL(client_connect_import);
-EXPORT_SYMBOL(client_disconnect_export);
-EXPORT_SYMBOL(server_disconnect_export);
-EXPORT_SYMBOL(target_stop_recovery_thread);
-EXPORT_SYMBOL(target_handle_connect);
-EXPORT_SYMBOL(target_cleanup_recovery);
-EXPORT_SYMBOL(target_destroy_export);
-EXPORT_SYMBOL(target_cancel_recovery_timer);
-EXPORT_SYMBOL(target_send_reply);
-EXPORT_SYMBOL(target_queue_recovery_request);
-EXPORT_SYMBOL(target_handle_ping);
-EXPORT_SYMBOL(target_pack_pool_reply);
-EXPORT_SYMBOL(target_handle_disconnect);
-
-/* l_lock.c */
-EXPORT_SYMBOL(lock_res_and_lock);
-EXPORT_SYMBOL(unlock_res_and_lock);
+       kmem_cache_destroy(ldlm_lock_slab);
+       kmem_cache_destroy(ldlm_interval_slab);
+}