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LU-6852 ldlm: Do not evict MDS-MDS connection
[fs/lustre-release.git] / lustre / ldlm / ldlm_lockd.c
index 5517ed5..760feb5 100644 (file)
@@ -27,7 +27,7 @@
  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2010, 2012, Intel Corporation.
+ * Copyright (c) 2010, 2014, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
 
 #define DEBUG_SUBSYSTEM S_LDLM
 
-#ifdef __KERNEL__
-# include <libcfs/libcfs.h>
-#else
-# include <liblustre.h>
-#endif
-
+#include <linux/kthread.h>
+#include <libcfs/libcfs.h>
 #include <lustre_dlm.h>
 #include <obd_class.h>
 #include <libcfs/list.h>
@@ -60,8 +56,6 @@ static char *ldlm_cpts;
 CFS_MODULE_PARM(ldlm_cpts, "s", charp, 0444,
                "CPU partitions ldlm threads should run on");
 
-extern cfs_mem_cache_t *ldlm_resource_slab;
-extern cfs_mem_cache_t *ldlm_lock_slab;
 static struct mutex    ldlm_ref_mutex;
 static int ldlm_refcount;
 
@@ -95,40 +89,40 @@ static inline unsigned int ldlm_get_rq_timeout(void)
 struct ldlm_bl_pool {
        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;
-       struct completion        blp_comp;
-        cfs_atomic_t            blp_num_threads;
-        cfs_atomic_t            blp_busy_threads;
-        int                     blp_min_threads;
-        int                     blp_max_threads;
+       /*
+        * 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
+        */
+       struct list_head              blp_prio_list;
+
+       /*
+        * blp_list is used for all other callbacks which are likely
+        * to take longer to process.
+        */
+       struct list_head              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 {
-        cfs_list_t              blwi_entry;
-        struct ldlm_namespace  *blwi_ns;
-        struct ldlm_lock_desc   blwi_ld;
-        struct ldlm_lock       *blwi_lock;
-        cfs_list_t              blwi_head;
-        int                     blwi_count;
-       struct completion        blwi_comp;
-        int                     blwi_mode;
-        int                     blwi_mem_pressure;
+       struct list_head        blwi_entry;
+       struct ldlm_namespace   *blwi_ns;
+       struct ldlm_lock_desc   blwi_ld;
+       struct ldlm_lock        *blwi_lock;
+       struct list_head        blwi_head;
+       int                     blwi_count;
+       struct completion       blwi_comp;
+       enum ldlm_cancel_flags  blwi_flags;
+       int                     blwi_mem_pressure;
 };
 
-#if defined(HAVE_SERVER_SUPPORT) && defined(__KERNEL__)
+#ifdef HAVE_SERVER_SUPPORT
 
 /**
  * Protects both waiting_locks_list and expired_lock_thread.
@@ -146,14 +140,14 @@ static spinlock_t waiting_locks_spinlock;   /* BH lock (timer) */
  *
  * All access to it should be under waiting_locks_spinlock.
  */
-static cfs_list_t waiting_locks_list;
-static cfs_timer_t waiting_locks_timer;
+static struct list_head waiting_locks_list;
+static struct timer_list waiting_locks_timer;
 
 static struct expired_lock_thread {
-       cfs_waitq_t             elt_waitq;
+       wait_queue_head_t       elt_waitq;
        int                     elt_state;
        int                     elt_dump;
-       cfs_list_t              elt_expired_locks;
+       struct list_head                elt_expired_locks;
 } expired_lock_thread;
 
 static inline int have_expired_locks(void)
@@ -162,7 +156,7 @@ static inline int have_expired_locks(void)
 
        ENTRY;
        spin_lock_bh(&waiting_locks_spinlock);
-       need_to_run = !cfs_list_empty(&expired_lock_thread.elt_expired_locks);
+       need_to_run = !list_empty(&expired_lock_thread.elt_expired_locks);
        spin_unlock_bh(&waiting_locks_spinlock);
 
        RETURN(need_to_run);
@@ -173,21 +167,20 @@ static inline int have_expired_locks(void)
  */
 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;
+       struct list_head *expired = &expired_lock_thread.elt_expired_locks;
+       struct l_wait_info lwi = { 0 };
+       int do_dump;
 
-        ENTRY;
-        cfs_daemonize("ldlm_elt");
+       ENTRY;
 
-        expired_lock_thread.elt_state = ELT_READY;
-        cfs_waitq_signal(&expired_lock_thread.elt_waitq);
+       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);
+       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) {
@@ -202,38 +195,39 @@ static int expired_lock_main(void *arg)
                        libcfs_run_lbug_upcall(&msgdata);
 
                        spin_lock_bh(&waiting_locks_spinlock);
-                        expired_lock_thread.elt_dump = 0;
-                }
+                       expired_lock_thread.elt_dump = 0;
+               }
 
-                do_dump = 0;
+               do_dump = 0;
 
-                while (!cfs_list_empty(expired)) {
-                        struct obd_export *export;
-                        struct ldlm_lock *lock;
+               while (!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) {
+                       lock = 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 + 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;
-                        }
+                               CERROR("free lock on elt list %p\n", lock);
+                               LBUG();
+                       }
+                       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 (lock->l_destroyed) {
+                       if (ldlm_is_destroyed(lock)) {
                                /* release the lock refcount where
                                 * waiting_locks_callback() founds */
                                LDLM_LOCK_RELEASE(lock);
@@ -242,6 +236,10 @@ static int expired_lock_main(void *arg)
                        export = class_export_lock_get(lock->l_export, lock);
                        spin_unlock_bh(&waiting_locks_spinlock);
 
+                       spin_lock_bh(&export->exp_bl_list_lock);
+                       list_del_init(&lock->l_exp_list);
+                       spin_unlock_bh(&export->exp_bl_list_lock);
+
                        do_dump++;
                        class_fail_export(export);
                        class_export_lock_put(export, lock);
@@ -254,18 +252,18 @@ static int expired_lock_main(void *arg)
                }
                spin_unlock_bh(&waiting_locks_spinlock);
 
-                if (do_dump && obd_dump_on_eviction) {
-                        CERROR("dump the log upon eviction\n");
-                        libcfs_debug_dumplog();
-                }
+               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;
-        }
+               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);
+       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);
@@ -285,7 +283,7 @@ static int ldlm_lock_busy(struct ldlm_lock *lock)
                return 0;
 
        spin_lock_bh(&lock->l_export->exp_rpc_lock);
-       cfs_list_for_each_entry(req, &lock->l_export->exp_hp_rpcs,
+       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);
@@ -304,61 +302,14 @@ static void waiting_locks_callback(unsigned long unused)
        int                     need_dump = 0;
 
        spin_lock_bh(&waiting_locks_spinlock);
-        while (!cfs_list_empty(&waiting_locks_list)) {
-                lock = cfs_list_entry(waiting_locks_list.next, struct ldlm_lock,
+       while (!list_empty(&waiting_locks_list)) {
+               lock = list_entry(waiting_locks_list.next, struct ldlm_lock,
                                       l_pending_chain);
                 if (cfs_time_after(lock->l_callback_timeout,
                                    cfs_time_current()) ||
                     (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);
-                       if (lock->l_destroyed) {
-                               /* relay the lock refcount decrease to
-                                * expired lock thread */
-                               cfs_list_add(&lock->l_pending_chain,
-                                       &expired_lock_thread.elt_expired_locks);
-                       } else {
-                               __ldlm_add_waiting_lock(lock,
-                                               ldlm_get_enq_timeout(lock));
-                       }
-                       continue;
-                }
-
-                /* 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);
-                       if (lock->l_destroyed) {
-                               /* relay the lock refcount decrease to
-                                * expired lock thread */
-                               cfs_list_add(&lock->l_pending_chain,
-                                       &expired_lock_thread.elt_expired_locks);
-                       } else {
-                               __ldlm_add_waiting_lock(lock,
-                                               ldlm_get_enq_timeout(lock));
-                       }
-                       continue;
-                }
-
                 /* Check if we need to prolong timeout */
                 if (!OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_HPREQ_TIMEOUT) &&
                     ldlm_lock_busy(lock)) {
@@ -372,7 +323,7 @@ static void waiting_locks_callback(unsigned long unused)
                        spin_unlock_bh(&waiting_locks_spinlock);
                        LDLM_DEBUG(lock, "prolong the busy lock");
                        ldlm_refresh_waiting_lock(lock,
-                                                 ldlm_get_enq_timeout(lock));
+                                                 ldlm_bl_timeout(lock) >> 1);
                        spin_lock_bh(&waiting_locks_spinlock);
 
                         if (!cont) {
@@ -386,33 +337,33 @@ static void waiting_locks_callback(unsigned long unused)
                 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));
 
                 /* no needs to take an extra ref on the lock since it was in
                  * the waiting_locks_list and ldlm_add_waiting_lock()
                  * already grabbed a ref */
-                cfs_list_del(&lock->l_pending_chain);
-                cfs_list_add(&lock->l_pending_chain,
+               list_del(&lock->l_pending_chain);
+               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 (!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
          * left.
          */
-        if (!cfs_list_empty(&waiting_locks_list)) {
+       if (!list_empty(&waiting_locks_list)) {
                 cfs_time_t timeout_rounded;
-                lock = cfs_list_entry(waiting_locks_list.next, struct ldlm_lock,
+               lock = list_entry(waiting_locks_list.next, struct ldlm_lock,
                                       l_pending_chain);
                 timeout_rounded = (cfs_time_t)round_timeout(lock->l_callback_timeout);
                 cfs_timer_arm(&waiting_locks_timer, timeout_rounded);
@@ -437,7 +388,7 @@ static int __ldlm_add_waiting_lock(struct ldlm_lock *lock, int seconds)
         cfs_time_t timeout;
         cfs_time_t timeout_rounded;
 
-        if (!cfs_list_empty(&lock->l_pending_chain))
+       if (!list_empty(&lock->l_pending_chain))
                 return 0;
 
         if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_HPREQ_NOTIMEOUT) ||
@@ -458,48 +409,77 @@ static int __ldlm_add_waiting_lock(struct ldlm_lock *lock, int seconds)
         /* if the new lock has a shorter timeout than something earlier on
            the list, we'll wait the longer amount of time; no big deal. */
         /* FIFO */
-        cfs_list_add_tail(&lock->l_pending_chain, &waiting_locks_list);
+       list_add_tail(&lock->l_pending_chain, &waiting_locks_list);
         return 1;
 }
 
+static void ldlm_add_blocked_lock(struct ldlm_lock *lock)
+{
+       spin_lock_bh(&lock->l_export->exp_bl_list_lock);
+       if (list_empty(&lock->l_exp_list)) {
+               if (lock->l_granted_mode != lock->l_req_mode)
+                       list_add_tail(&lock->l_exp_list,
+                                     &lock->l_export->exp_bl_list);
+               else
+                       list_add(&lock->l_exp_list,
+                                &lock->l_export->exp_bl_list);
+       }
+       spin_unlock_bh(&lock->l_export->exp_bl_list_lock);
+
+       /* A blocked lock is added. Adjust the position in
+        * the stale list if the export is in the list.
+        * If export is stale and not in the list - it is being
+        * processed and will be placed on the right position
+        * on obd_stale_export_put(). */
+       if (!list_empty(&lock->l_export->exp_stale_list))
+               obd_stale_export_adjust(lock->l_export);
+}
+
 static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
 {
        int ret;
-       int timeout = ldlm_get_enq_timeout(lock);
+       int timeout = ldlm_bl_timeout(lock);
 
        /* NB: must be called with hold of lock_res_and_lock() */
-       LASSERT(lock->l_res_locked);
-       lock->l_waited = 1;
+       LASSERT(ldlm_is_res_locked(lock));
+       LASSERT(!ldlm_is_cancel_on_block(lock));
 
-       LASSERT(!(lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK));
+       /* Do not put cross-MDT lock in the waiting list, since we
+        * will not evict it due to timeout for now */
+       if (lock->l_export != NULL &&
+           (exp_connect_flags(lock->l_export) & OBD_CONNECT_MDS_MDS))
+               return 0;
 
        spin_lock_bh(&waiting_locks_spinlock);
-       if (lock->l_destroyed) {
-               static cfs_time_t next;
+       if (ldlm_is_cancel(lock)) {
                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);
-                        libcfs_debug_dumpstack(NULL);
-                }
-                return 0;
-        }
+               return 0;
+       }
 
-        ret = __ldlm_add_waiting_lock(lock, timeout);
-        if (ret) {
-                /* grab ref on the lock if it has been added to the
-                 * waiting list */
-                LDLM_LOCK_GET(lock);
-        }
-       spin_unlock_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);
+                       libcfs_debug_dumpstack(NULL);
+               }
+               return 0;
+       }
 
+       ldlm_set_waited(lock);
+       lock->l_last_activity = cfs_time_current_sec();
+       ret = __ldlm_add_waiting_lock(lock, timeout);
        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);
+               /* grab ref on the lock if it has been added to the
+                * waiting list */
+               LDLM_LOCK_GET(lock);
        }
+       spin_unlock_bh(&waiting_locks_spinlock);
+
+       if (ret)
+               ldlm_add_blocked_lock(lock);
 
        LDLM_DEBUG(lock, "%sadding to wait list(timeout: %d, AT: %s)",
                   ret == 0 ? "not re-" : "", timeout,
@@ -518,9 +498,9 @@ static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
  */
 static int __ldlm_del_waiting_lock(struct ldlm_lock *lock)
 {
-        cfs_list_t *list_next;
+       struct list_head *list_next;
 
-        if (cfs_list_empty(&lock->l_pending_chain))
+       if (list_empty(&lock->l_pending_chain))
                 return 0;
 
         list_next = lock->l_pending_chain.next;
@@ -531,13 +511,13 @@ static int __ldlm_del_waiting_lock(struct ldlm_lock *lock)
                         cfs_timer_disarm(&waiting_locks_timer);
                 } else {
                         struct ldlm_lock *next;
-                        next = cfs_list_entry(list_next, struct ldlm_lock,
+                       next = list_entry(list_next, struct ldlm_lock,
                                               l_pending_chain);
                         cfs_timer_arm(&waiting_locks_timer,
                                       round_timeout(next->l_callback_timeout));
                 }
         }
-        cfs_list_del_init(&lock->l_pending_chain);
+       list_del_init(&lock->l_pending_chain);
 
         return 1;
 }
@@ -554,11 +534,12 @@ int ldlm_del_waiting_lock(struct ldlm_lock *lock)
 
        spin_lock_bh(&waiting_locks_spinlock);
        ret = __ldlm_del_waiting_lock(lock);
+       ldlm_clear_waited(lock);
        spin_unlock_bh(&waiting_locks_spinlock);
 
        /* 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);
+       list_del_init(&lock->l_exp_list);
        spin_unlock_bh(&lock->l_export->exp_bl_list_lock);
 
         if (ret) {
@@ -570,7 +551,6 @@ 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 contended lock waiting time.
@@ -585,9 +565,15 @@ int ldlm_refresh_waiting_lock(struct ldlm_lock *lock, int timeout)
                return 0;
        }
 
+       if (exp_connect_flags(lock->l_export) & OBD_CONNECT_MDS_MDS) {
+               /* We don't have a "waiting locks list" on OSP. */
+               LDLM_DEBUG(lock, "MDS-MDS lock: no-op");
+               return 0;
+       }
+
        spin_lock_bh(&waiting_locks_spinlock);
 
-       if (cfs_list_empty(&lock->l_pending_chain)) {
+       if (list_empty(&lock->l_pending_chain)) {
                spin_unlock_bh(&waiting_locks_spinlock);
                LDLM_DEBUG(lock, "wasn't waiting");
                return 0;
@@ -604,7 +590,7 @@ int ldlm_refresh_waiting_lock(struct ldlm_lock *lock, int timeout)
 }
 EXPORT_SYMBOL(ldlm_refresh_waiting_lock);
 
-#else /* !HAVE_SERVER_SUPPORT ||  !__KERNEL__ */
+#else /* HAVE_SERVER_SUPPORT */
 
 int ldlm_del_waiting_lock(struct ldlm_lock *lock)
 {
@@ -616,18 +602,34 @@ int ldlm_refresh_waiting_lock(struct ldlm_lock *lock, int timeout)
         RETURN(0);
 }
 
-# ifdef HAVE_SERVER_SUPPORT
-static int ldlm_add_waiting_lock(struct ldlm_lock *lock)
+#endif /* !HAVE_SERVER_SUPPORT */
+
+#ifdef HAVE_SERVER_SUPPORT
+
+/**
+ * Calculate the per-export Blocking timeout (covering BL AST, data flush,
+ * lock cancel, and their replies). Used for lock callback timeout and AST
+ * re-send period.
+ *
+ * \param[in] lock        lock which is getting the blocking callback
+ *
+ * \retval            timeout in seconds to wait for the client reply
+ */
+unsigned int ldlm_bl_timeout(struct ldlm_lock *lock)
 {
-       LASSERT(lock->l_res_locked);
-       LASSERT(!(lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK));
-       RETURN(1);
-}
+       unsigned int timeout;
 
-# endif
-#endif /* HAVE_SERVER_SUPPORT && __KERNEL__ */
+       if (AT_OFF)
+               return obd_timeout / 2;
 
-#ifdef HAVE_SERVER_SUPPORT
+       /* Since these are non-updating timeouts, we should be conservative.
+        * Take more than usually, 150%
+        * It would be nice to have some kind of "early reply" mechanism for
+        * lock callbacks too... */
+       timeout = at_get(&lock->l_export->exp_bl_lock_at);
+       return max(timeout + (timeout >> 1), ldlm_enqueue_min);
+}
+EXPORT_SYMBOL(ldlm_bl_timeout);
 
 /**
  * Perform lock cleanup if AST sending failed.
@@ -642,19 +644,15 @@ static void ldlm_failed_ast(struct ldlm_lock *lock, int rc,
 
         if (obd_dump_on_timeout)
                 libcfs_debug_dumplog();
-#ifdef __KERNEL__
        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,
+       list_add(&lock->l_pending_chain,
                     &expired_lock_thread.elt_expired_locks);
-       cfs_waitq_signal(&expired_lock_thread.elt_waitq);
+       wake_up(&expired_lock_thread.elt_waitq);
        spin_unlock_bh(&waiting_locks_spinlock);
-#else
-       class_fail_export(lock->l_export);
-#endif
 }
 
 /**
@@ -664,57 +662,57 @@ static int ldlm_handle_ast_error(struct ldlm_lock *lock,
                                  struct ptlrpc_request *req, int rc,
                                  const char *ast_type)
 {
-        lnet_process_id_t peer = req->rq_import->imp_connection->c_peer;
-
-        if (rc == -ETIMEDOUT || rc == -EINTR || rc == -ENOTCONN) {
-                LASSERT(lock->l_export);
-                if (lock->l_export->exp_libclient) {
-                        LDLM_DEBUG(lock, "%s AST to liblustre client (nid %s)"
-                                   " timeout, just cancelling lock", ast_type,
-                                   libcfs_nid2str(peer.nid));
-                        ldlm_lock_cancel(lock);
-                        rc = -ERESTART;
-                } else if (lock->l_flags & LDLM_FL_CANCEL) {
-                        LDLM_DEBUG(lock, "%s AST timeout from nid %s, but "
-                                   "cancel was received (AST reply lost?)",
-                                   ast_type, libcfs_nid2str(peer.nid));
-                        ldlm_lock_cancel(lock);
-                        rc = -ERESTART;
-                } else {
-                        ldlm_del_waiting_lock(lock);
-                        ldlm_failed_ast(lock, rc, ast_type);
-                }
-        } else if (rc) {
-                if (rc == -EINVAL) {
-                        struct ldlm_resource *res = lock->l_resource;
-                        LDLM_DEBUG(lock, "client (nid %s) returned %d"
-                               " from %s AST - normal race",
-                               libcfs_nid2str(peer.nid),
-                               req->rq_repmsg ?
-                               lustre_msg_get_status(req->rq_repmsg) : -1,
-                               ast_type);
-                        if (res) {
-                                /* update lvbo to return proper attributes.
-                                 * see bug 23174 */
-                                ldlm_resource_getref(res);
-                                ldlm_res_lvbo_update(res, NULL, 1);
-                                ldlm_resource_putref(res);
-                        }
+       lnet_process_id_t peer = req->rq_import->imp_connection->c_peer;
+
+       if (!req->rq_replied || (rc && rc != -EINVAL)) {
+               if (lock->l_export && lock->l_export->exp_libclient) {
+                       LDLM_DEBUG(lock, "%s AST to liblustre client (nid %s)"
+                                  " timeout, just cancelling lock", ast_type,
+                                  libcfs_nid2str(peer.nid));
+                       ldlm_lock_cancel(lock);
+                       rc = -ERESTART;
+               } 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));
+                       ldlm_lock_cancel(lock);
+                       rc = -ERESTART;
+               } else {
+                       LDLM_ERROR(lock, "client (nid %s) %s %s AST "
+                                  "(req status %d rc %d), evict it",
+                                  libcfs_nid2str(peer.nid),
+                                  req->rq_replied ? "returned error from" :
+                                  "failed to reply to",
+                                  ast_type,
+                                  (req->rq_repmsg != NULL) ?
+                                  lustre_msg_get_status(req->rq_repmsg) : 0,
+                                  rc);
+                       ldlm_failed_ast(lock, rc, ast_type);
+               }
+               return rc;
+       }
 
-                } else {
-                        LDLM_ERROR(lock, "client (nid %s) returned %d "
-                                   "from %s AST", libcfs_nid2str(peer.nid),
-                                   (req->rq_repmsg != NULL) ?
-                                   lustre_msg_get_status(req->rq_repmsg) : 0,
-                                   ast_type);
-                }
-                ldlm_lock_cancel(lock);
-                /* Server-side AST functions are called from ldlm_reprocess_all,
-                 * which needs to be told to please restart its reprocessing. */
-                rc = -ERESTART;
-        }
+       if (rc == -EINVAL) {
+               struct ldlm_resource *res = lock->l_resource;
+
+               LDLM_DEBUG(lock, "client (nid %s) returned %d"
+                          " from %s AST - normal race",
+                          libcfs_nid2str(peer.nid),
+                          req->rq_repmsg ?
+                          lustre_msg_get_status(req->rq_repmsg) : -1,
+                          ast_type);
+               if (res) {
+                       /* update lvbo to return proper attributes.
+                        * see bug 23174 */
+                       ldlm_resource_getref(res);
+                       ldlm_res_lvbo_update(res, NULL, 1);
+                       ldlm_resource_putref(res);
+               }
+               ldlm_lock_cancel(lock);
+               rc = -ERESTART;
+       }
 
-        return rc;
+       return rc;
 }
 
 static int ldlm_cb_interpret(const struct lu_env *env,
@@ -765,9 +763,17 @@ static int ldlm_cb_interpret(const struct lu_env *env,
         LDLM_LOCK_RELEASE(lock);
 
        if (rc == -ERESTART)
-               cfs_atomic_inc(&arg->restart);
+               atomic_inc(&arg->restart);
 
-        RETURN(0);
+       RETURN(0);
+}
+
+static void ldlm_update_resend(struct ptlrpc_request *req, void *data)
+{
+       struct ldlm_cb_async_args *ca   = data;
+       struct ldlm_lock          *lock = ca->ca_lock;
+
+       ldlm_refresh_waiting_lock(lock, ldlm_bl_timeout(lock));
 }
 
 static inline int ldlm_ast_fini(struct ptlrpc_request *req,
@@ -782,7 +788,7 @@ static inline int ldlm_ast_fini(struct ptlrpc_request *req,
                rc = ptl_send_rpc(req, 1);
                ptlrpc_req_finished(req);
                if (rc == 0)
-                       cfs_atomic_inc(&arg->restart);
+                       atomic_inc(&arg->restart);
        } else {
                LDLM_LOCK_GET(lock);
                ptlrpc_set_add_req(arg->set, req);
@@ -797,25 +803,28 @@ static inline int ldlm_ast_fini(struct ptlrpc_request *req,
  */
 static void ldlm_lock_reorder_req(struct ldlm_lock *lock)
 {
-        struct ptlrpc_request *req;
-        ENTRY;
+       struct ptlrpc_request *req;
+       ENTRY;
 
-        if (lock->l_export == NULL) {
-                LDLM_DEBUG(lock, "client lock: no-op");
-                RETURN_EXIT;
-        }
+       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 */
-                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);
-        }
+       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;
 }
@@ -862,33 +871,34 @@ int ldlm_server_blocking_ast(struct ldlm_lock *lock,
         ca->ca_lock = lock;
 
         req->rq_interpret_reply = ldlm_cb_interpret;
-        req->rq_no_resend = 1;
 
        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 */
+       if (ldlm_is_destroyed(lock)) {
+               /* What's the point? */
                unlock_res_and_lock(lock);
-
                ptlrpc_req_finished(req);
-               LDLM_DEBUG(lock, "lock not granted, not sending blocking AST");
                RETURN(0);
        }
 
-       if (lock->l_destroyed) {
-               /* What's the point? */
+       if (lock->l_granted_mode != lock->l_req_mode) {
+               /* this blocking AST will be communicated as part of the
+                * completion AST instead */
+               ldlm_add_blocked_lock(lock);
+               ldlm_set_waited(lock);
                unlock_res_and_lock(lock);
+
                ptlrpc_req_finished(req);
+               LDLM_DEBUG(lock, "lock not granted, not sending blocking AST");
                RETURN(0);
        }
 
-        if (lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK)
+       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 |= ldlm_flags_to_wire(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");
 
@@ -896,10 +906,16 @@ int ldlm_server_blocking_ast(struct ldlm_lock *lock,
        if (instant_cancel) {
                unlock_res_and_lock(lock);
                ldlm_lock_cancel(lock);
+
+               req->rq_no_resend = 1;
        } else {
                LASSERT(lock->l_granted_mode == lock->l_req_mode);
                ldlm_add_waiting_lock(lock);
                unlock_res_and_lock(lock);
+
+               /* Do not resend after lock callback timeout */
+               req->rq_delay_limit = ldlm_bl_timeout(lock);
+               req->rq_resend_cb = ldlm_update_resend;
        }
 
         req->rq_send_state = LUSTRE_IMP_FULL;
@@ -907,6 +923,8 @@ int ldlm_server_blocking_ast(struct ldlm_lock *lock,
         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,
@@ -916,7 +934,6 @@ int ldlm_server_blocking_ast(struct ldlm_lock *lock,
 
         RETURN(rc);
 }
-EXPORT_SYMBOL(ldlm_server_blocking_ast);
 
 /**
  * ->l_completion_ast callback for a remote lock in server namespace.
@@ -931,7 +948,6 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
         struct ldlm_request    *body;
         struct ptlrpc_request  *req;
         struct ldlm_cb_async_args *ca;
-        long                    total_enqueue_wait;
         int                     instant_cancel = 0;
         int                     rc = 0;
        int                     lvb_len;
@@ -940,8 +956,10 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
         LASSERT(lock != NULL);
         LASSERT(data != NULL);
 
-        total_enqueue_wait = cfs_time_sub(cfs_time_current_sec(),
-                                          lock->l_last_activity);
+       if (OBD_FAIL_PRECHECK(OBD_FAIL_LDLM_SRV_CP_AST)) {
+               LDLM_DEBUG(lock, "dropping CP AST");
+               RETURN(0);
+       }
 
         req = ptlrpc_request_alloc(lock->l_export->exp_imp_reverse,
                                     &RQF_LDLM_CP_CALLBACK);
@@ -950,6 +968,13 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
 
        /* 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) {
@@ -963,7 +988,6 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
         ca->ca_lock = lock;
 
         req->rq_interpret_reply = ldlm_cb_interpret;
-        req->rq_no_resend = 1;
         body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
 
         body->lock_handle[0] = lock->l_remote_handle;
@@ -973,27 +997,25 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
                void *lvb = req_capsule_client_get(&req->rq_pill, &RMF_DLM_LVB);
 
                lvb_len = ldlm_lvbo_fill(lock, lvb, lvb_len);
-               req_capsule_shrink(&req->rq_pill, &RMF_DLM_LVB,
-                                  lvb_len, RCL_CLIENT);
+               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))
-                at_measured(ldlm_lock_to_ns_at(lock),
-                            total_enqueue_wait);
-        else
-                /* bz18618. Don't add lock enqueue time we spend waiting for a
-                   previous callback to fail. Locks waiting legitimately will
-                   get extended by ldlm_refresh_waiting_lock regardless of the
-                   estimate, so it's okay to underestimate here. */
-                LDLM_DEBUG(lock, "lock completed after %lus; estimate was %ds. "
-                       "It is likely that a previous callback timed out.",
-                       total_enqueue_wait,
-                       at_get(ldlm_lock_to_ns_at(lock)));
+       LDLM_DEBUG(lock, "server preparing completion AST");
 
         ptlrpc_request_set_replen(req);
 
@@ -1004,11 +1026,11 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 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) {
+       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_AST_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
@@ -1016,15 +1038,21 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 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) {
-                        unlock_res_and_lock(lock);
-                        ldlm_lock_cancel(lock);
-                        instant_cancel = 1;
-                        lock_res_and_lock(lock);
-                } else {
-                        /* start the lock-timeout clock */
-                        ldlm_add_waiting_lock(lock);
-                }
+               if (ldlm_is_cancel_on_block(lock)) {
+                       unlock_res_and_lock(lock);
+                       ldlm_lock_cancel(lock);
+
+                       instant_cancel = 1;
+                       req->rq_no_resend = 1;
+
+                       lock_res_and_lock(lock);
+               } else {
+                       /* start the lock-timeout clock */
+                       ldlm_add_waiting_lock(lock);
+                       /* Do not resend after lock callback timeout */
+                       req->rq_delay_limit = ldlm_bl_timeout(lock);
+                       req->rq_resend_cb = ldlm_update_resend;
+               }
         }
         unlock_res_and_lock(lock);
 
@@ -1035,9 +1063,8 @@ int ldlm_server_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
 
        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.
@@ -1096,6 +1123,8 @@ int ldlm_server_glimpse_ast(struct ldlm_lock *lock, void *data)
         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 &&
@@ -1107,9 +1136,9 @@ int ldlm_server_glimpse_ast(struct ldlm_lock *lock, void *data)
 
        RETURN(rc);
 }
-EXPORT_SYMBOL(ldlm_server_glimpse_ast);
 
-int ldlm_glimpse_locks(struct ldlm_resource *res, cfs_list_t *gl_work_list)
+int ldlm_glimpse_locks(struct ldlm_resource *res,
+                      struct list_head *gl_work_list)
 {
        int     rc;
        ENTRY;
@@ -1178,24 +1207,25 @@ static void ldlm_svc_get_eopc(const struct ldlm_request *dlm_req,
  * service threads to carry out client lock enqueueing requests.
  */
 int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
-                         struct ptlrpc_request *req,
-                         const struct ldlm_request *dlm_req,
-                         const struct ldlm_callback_suite *cbs)
+                        struct ptlrpc_request *req,
+                        const struct ldlm_request *dlm_req,
+                        const struct ldlm_callback_suite *cbs)
 {
-        struct ldlm_reply *dlm_rep;
+       struct ldlm_reply *dlm_rep;
        __u64 flags;
-        ldlm_error_t err = ELDLM_OK;
-        struct ldlm_lock *lock = NULL;
-        void *cookie = NULL;
-        int rc = 0;
-        ENTRY;
+       enum ldlm_error err = ELDLM_OK;
+       struct ldlm_lock *lock = NULL;
+       void *cookie = NULL;
+       int rc = 0;
+       struct ldlm_resource *res = NULL;
+       ENTRY;
 
-        LDLM_DEBUG_NOLOCK("server-side enqueue handler START");
+       LDLM_DEBUG_NOLOCK("server-side enqueue handler START");
 
-        ldlm_request_cancel(req, dlm_req, LDLM_ENQUEUE_CANCEL_OFF);
+       ldlm_request_cancel(req, dlm_req, LDLM_ENQUEUE_CANCEL_OFF, LATF_SKIP);
        flags = ldlm_flags_from_wire(dlm_req->lock_flags);
 
-        LASSERT(req->rq_export);
+       LASSERT(req->rq_export);
 
        if (ptlrpc_req2svc(req)->srv_stats != NULL)
                ldlm_svc_get_eopc(dlm_req, ptlrpc_req2svc(req)->srv_stats);
@@ -1221,7 +1251,7 @@ 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,
@@ -1242,7 +1272,7 @@ 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 =
@@ -1252,7 +1282,8 @@ 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() */
@@ -1262,22 +1293,47 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
                 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);
-                }
-        }
+               }
+       } else {
+               if (ldlm_reclaim_full()) {
+                       DEBUG_REQ(D_DLMTRACE, req, "Too many granted locks, "
+                                 "reject current enqueue request and let the "
+                                 "client retry later.\n");
+                       GOTO(out, rc = -EINPROGRESS);
+               }
+       }
 
-        /* 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,
+       /* 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 (!lock)
-                GOTO(out, rc = -ENOMEM);
+       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];
         LDLM_DEBUG(lock, "server-side enqueue handler, new lock created");
 
+       /* Initialize resource lvb but not for a lock being replayed since
+        * Client already got lvb sent in this case.
+        * This must occur early since some policy methods assume resource
+        * lvb is available (lr_lvb_data != NULL).
+        */
+       res = lock->l_resource;
+       if (!(flags & LDLM_FL_REPLAY)) {
+               /* non-replayed lock, delayed lvb init may need to be done */
+               rc = ldlm_lvbo_init(res);
+               if (rc < 0) {
+                       LDLM_DEBUG(lock, "delayed lvb init failed (rc %d)", rc);
+                       GOTO(out, rc);
+               }
+       }
+
         OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_ENQUEUE_BLOCKED, obd_timeout * 2);
         /* Don't enqueue a lock onto the export if it is been disonnected
          * due to eviction (bug 3822) or server umount (bug 24324).
@@ -1294,6 +1350,11 @@ int ldlm_handle_enqueue0(struct ldlm_namespace *ns,
                              &lock->l_remote_handle,
                              &lock->l_exp_hash);
 
+       /* Inherit the enqueue flags before the operation, because we do not
+        * keep the res lock on return and next operations (BL AST) may proceed
+        * without them. */
+       lock->l_flags |= ldlm_flags_from_wire(dlm_req->lock_flags &
+                                             LDLM_FL_INHERIT_MASK);
 existing_lock:
 
         if (flags & LDLM_FL_HAS_INTENT) {
@@ -1324,24 +1385,28 @@ existing_lock:
                 lock->l_req_extent = lock->l_policy_data.l_extent;
 
        err = ldlm_lock_enqueue(ns, &lock, cookie, &flags);
-        if (err)
-                GOTO(out, err);
+       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 = ldlm_flags_to_wire(flags);
 
         ldlm_lock2desc(lock, &dlm_rep->lock_desc);
         ldlm_lock2handle(lock, &dlm_rep->lock_handle);
 
+       if (lock && lock->l_resource->lr_type == LDLM_EXTENT)
+               OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_BL_EVICT, 6);
+
         /* We never send a blocking AST until the lock is granted, but
          * we can tell it right now */
         lock_res_and_lock(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 |= ldlm_flags_from_wire(dlm_req->lock_flags &
-                                             LDLM_INHERIT_FLAGS);
+       dlm_rep->lock_flags = ldlm_flags_to_wire(flags);
+       lock->l_flags |= 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).
@@ -1350,7 +1415,7 @@ 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) {
+       } 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) {
                         /*
@@ -1373,7 +1438,7 @@ 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",
@@ -1406,14 +1471,14 @@ 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) {
-                       int lvb_len = ldlm_lvbo_size(lock);
-
-                       if (lvb_len > 0) {
+       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;
 
@@ -1423,16 +1488,44 @@ existing_lock:
                                         req, lock);
                                buflen = req_capsule_get_size(&req->rq_pill,
                                                &RMF_DLM_LVB, RCL_SERVER);
-                               buflen = ldlm_lvbo_fill(lock, buf, buflen);
-                               req_capsule_shrink(&req->rq_pill, &RMF_DLM_LVB,
-                                                  buflen, RCL_SERVER);
+                               /* non-replayed lock, delayed lvb init may
+                                * need to be occur now */
+                               if ((buflen > 0) && !(flags & LDLM_FL_REPLAY)) {
+                                       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 if (flags & LDLM_FL_REPLAY) {
+                                       /* no LVB resend upon replay */
+                                       if (buflen > 0)
+                                               req_capsule_shrink(
+                                                       &req->rq_pill,
+                                                       &RMF_DLM_LVB,
+                                                       0, RCL_SERVER);
+                                       else
+                                               rc = buflen;
+                               } else {
+                                       rc = buflen;
+                               }
                        }
-                } else {
-                        lock_res_and_lock(lock);
-                        ldlm_resource_unlink_lock(lock);
-                        ldlm_lock_destroy_nolock(lock);
-                        unlock_res_and_lock(lock);
-                }
+               }
+
+               if (rc != 0) {
+                       if (lock->l_export) {
+                               ldlm_lock_cancel(lock);
+                       } else {
+                               lock_res_and_lock(lock);
+                               ldlm_resource_unlink_lock(lock);
+                               ldlm_lock_destroy_nolock(lock);
+                               unlock_res_and_lock(lock);
+
+                       }
+               }
 
                 if (!err && dlm_req->lock_desc.l_resource.lr_type != LDLM_FLOCK)
                         ldlm_reprocess_all(lock->l_resource);
@@ -1445,7 +1538,6 @@ existing_lock:
 
         return rc;
 }
-EXPORT_SYMBOL(ldlm_handle_enqueue0);
 
 /**
  * Old-style LDLM main entry point for server code enqueue.
@@ -1472,7 +1564,6 @@ 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.
@@ -1499,13 +1590,12 @@ 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;
 
                 LDLM_DEBUG(lock, "server-side convert handler START");
 
-                lock->l_last_activity = cfs_time_current_sec();
                 res = ldlm_lock_convert(lock, dlm_req->lock_desc.l_req_mode,
                                         &dlm_rep->lock_flags);
                 if (res) {
@@ -1513,7 +1603,7 @@ 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;
                 }
         }
 
@@ -1527,7 +1617,6 @@ 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
@@ -1547,7 +1636,6 @@ int ldlm_handle_convert(struct ptlrpc_request *req)
         }
         return rc;
 }
-EXPORT_SYMBOL(ldlm_handle_convert);
 
 /**
  * Cancel all the locks whose handles are packed into ldlm_request
@@ -1556,7 +1644,8 @@ EXPORT_SYMBOL(ldlm_handle_convert);
  * requests.
  */
 int ldlm_request_cancel(struct ptlrpc_request *req,
-                        const struct ldlm_request *dlm_req, int first)
+                       const struct ldlm_request *dlm_req,
+                       int first, enum lustre_at_flags flags)
 {
         struct ldlm_resource *res, *pres = NULL;
         struct ldlm_lock *lock;
@@ -1606,6 +1695,14 @@ int ldlm_request_cancel(struct ptlrpc_request *req,
                         }
                         pres = res;
                 }
+
+               if ((flags & LATF_STATS) && ldlm_is_ast_sent(lock)) {
+                       long delay = cfs_time_sub(cfs_time_current_sec(),
+                                                 lock->l_last_activity);
+                       LDLM_DEBUG(lock, "server cancels blocked lock after "
+                                  CFS_DURATION_T"s", delay);
+                       at_measured(&lock->l_export->exp_bl_lock_at, delay);
+               }
                 ldlm_lock_cancel(lock);
                 LDLM_LOCK_PUT(lock);
         }
@@ -1645,12 +1742,11 @@ int ldlm_handle_cancel(struct ptlrpc_request *req)
         if (rc)
                 RETURN(rc);
 
-        if (!ldlm_request_cancel(req, dlm_req, 0))
-                req->rq_status = ESTALE;
+       if (!ldlm_request_cancel(req, dlm_req, 0, LATF_STATS))
+               req->rq_status = LUSTRE_ESTALE;
 
         RETURN(ptlrpc_reply(req));
 }
-EXPORT_SYMBOL(ldlm_handle_cancel);
 #endif /* HAVE_SERVER_SUPPORT */
 
 /**
@@ -1667,10 +1763,10 @@ 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);
@@ -1701,23 +1797,24 @@ static void ldlm_handle_cp_callback(struct ptlrpc_request *req,
                                     struct ldlm_request *dlm_req,
                                     struct ldlm_lock *lock)
 {
+       struct list_head ast_list;
        int lvb_len;
-        CFS_LIST_HEAD(ast_list);
        int rc = 0;
-        ENTRY;
+       ENTRY;
 
-        LDLM_DEBUG(lock, "client completion callback handler START");
+       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;
-                }
-        }
+       INIT_LIST_HEAD(&ast_list);
+       if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_BL_CB_RACE)) {
+               int to = cfs_time_seconds(1);
+               while (to > 0) {
+                       set_current_state(TASK_INTERRUPTIBLE);
+                       schedule_timeout(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) {
@@ -1735,46 +1832,32 @@ static void ldlm_handle_cp_callback(struct ptlrpc_request *req,
                                           lock->l_lvb_len, lvb_len);
                                GOTO(out, rc = -EINVAL);
                        }
-               } else { /* for layout lock, lvb has variable length */
-                       void *lvb_data;
-
-                       OBD_ALLOC(lvb_data, lvb_len);
-                       if (lvb_data == NULL) {
-                               LDLM_ERROR(lock, "No memory.\n");
-                               GOTO(out, rc = -ENOMEM);
-                       }
-
-                       lock_res_and_lock(lock);
-                       LASSERT(lock->l_lvb_data == NULL);
-                       lock->l_lvb_data = lvb_data;
-                       lock->l_lvb_len = lvb_len;
-                       unlock_res_and_lock(lock);
                }
        }
 
-        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");
+       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 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");
-        }
+       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,
@@ -1796,7 +1879,7 @@ static void ldlm_handle_cp_callback(struct ptlrpc_request *req,
                /* 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");
         }
 
@@ -1827,8 +1910,9 @@ static void ldlm_handle_cp_callback(struct ptlrpc_request *req,
 out:
        if (rc < 0) {
                lock_res_and_lock(lock);
-               lock->l_flags |= LDLM_FL_FAILED;
+               ldlm_set_failed(lock);
                unlock_res_and_lock(lock);
+               wake_up(&lock->l_waitq);
        }
        LDLM_LOCK_RELEASE(lock);
 }
@@ -1892,53 +1976,53 @@ static int ldlm_callback_reply(struct ptlrpc_request *req, int rc)
         return ptlrpc_reply(req);
 }
 
-#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,
+                              enum ldlm_cancel_flags cancel_flags)
 {
        struct ldlm_bl_pool *blp = ldlm_state->ldlm_bl_pool;
        ENTRY;
 
        spin_lock(&blp->blp_lock);
        if (blwi->blwi_lock &&
-           blwi->blwi_lock->l_flags & LDLM_FL_DISCARD_DATA) {
+           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);
+               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);
+               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)
+       /* 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);
 }
 
 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,
+                            struct list_head *cancels, int count,
+                            struct ldlm_lock *lock,
+                            enum ldlm_cancel_flags cancel_flags)
 {
        init_completion(&blwi->blwi_comp);
-        CFS_INIT_LIST_HEAD(&blwi->blwi_head);
+       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) {
-                cfs_list_add(&blwi->blwi_head, cancels);
-                cfs_list_del_init(cancels);
+               list_add(&blwi->blwi_head, cancels);
+               list_del_init(cancels);
                 blwi->blwi_count = count;
         } else {
                 blwi->blwi_lock = lock;
@@ -1955,53 +2039,55 @@ static inline void init_blwi(struct ldlm_bl_work_item *blwi,
  * 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,
+                            struct list_head *cancels, int count,
+                            enum ldlm_cancel_flags 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));
-#else
-        RETURN(-ENOSYS);
-#endif
+       return ldlm_bl_to_thread(ns, ld, lock, NULL, 0, LCF_ASYNC);
 }
 
 int ldlm_bl_to_thread_list(struct ldlm_namespace *ns, struct ldlm_lock_desc *ld,
-                           cfs_list_t *cancels, int count, int mode)
+                          struct list_head *cancels, int count,
+                          enum ldlm_cancel_flags cancel_flags)
 {
-#ifdef __KERNEL__
-        RETURN(ldlm_bl_to_thread(ns, ld, NULL, cancels, count, mode));
-#else
-        RETURN(-ENOSYS);
-#endif
+       return ldlm_bl_to_thread(ns, ld, NULL, cancels, count, cancel_flags);
+}
+
+int ldlm_bl_thread_wakeup(void)
+{
+       wake_up(&ldlm_state->ldlm_bl_pool->blp_waitq);
+       return 0;
 }
 
 /* Setinfo coming from Server (eg MDT) to Client (eg MDC)! */
@@ -2062,21 +2148,6 @@ 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);
-       }
-
-       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)
 {
@@ -2109,8 +2180,11 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
 
        switch (lustre_msg_get_opc(req->rq_reqmsg)) {
        case LDLM_BL_CALLBACK:
-               if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_BL_CALLBACK_NET))
+               if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_BL_CALLBACK_NET)) {
+                       if (cfs_fail_err)
+                               ldlm_callback_reply(req, -(int)cfs_fail_err);
                        RETURN(0);
+               }
                break;
        case LDLM_CP_CALLBACK:
                if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_CP_CALLBACK_NET))
@@ -2124,16 +2198,6 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
                 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 LLOG_ORIGIN_HANDLE_CREATE:
                 req_capsule_set(&req->rq_pill, &RQF_LLOG_ORIGIN_HANDLE_CREATE);
                 if (OBD_FAIL_CHECK(OBD_FAIL_OBD_LOGD_NET))
@@ -2163,13 +2227,6 @@ 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));
@@ -2194,7 +2251,7 @@ 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);
         }
@@ -2209,22 +2266,21 @@ 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 |= ldlm_flags_from_wire(dlm_req->lock_flags &
-                                             LDLM_AST_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);
@@ -2238,7 +2294,7 @@ static int ldlm_callback_handler(struct ptlrpc_request *req)
                /* 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);
 
@@ -2255,7 +2311,7 @@ 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,
@@ -2329,21 +2385,13 @@ static int ldlm_cancel_handler(struct ptlrpc_request *req)
                 req_capsule_set(&req->rq_pill, &RQF_LDLM_CANCEL);
                 CDEBUG(D_INODE, "cancel\n");
                if (CFS_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_NET) ||
-                   CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_CANCEL_RESEND))
+                   CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_CANCEL_RESEND) ||
+                   CFS_FAIL_CHECK(OBD_FAIL_LDLM_BL_EVICT))
                        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));
@@ -2405,7 +2453,7 @@ 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);
@@ -2439,11 +2487,11 @@ static int ldlm_hpreq_handler(struct ptlrpc_request *req)
         RETURN(0);
 }
 
-int ldlm_revoke_lock_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
-                        cfs_hlist_node_t *hnode, void *data)
+static int ldlm_revoke_lock_cb(struct cfs_hash *hs, struct cfs_hash_bd *bd,
+                              struct hlist_node *hnode, void *data)
 
 {
-        cfs_list_t         *rpc_list = data;
+       struct list_head         *rpc_list = data;
         struct ldlm_lock   *lock = cfs_hash_object(hs, hnode);
 
         lock_res_and_lock(lock);
@@ -2460,7 +2508,7 @@ 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;
         }
@@ -2468,7 +2516,7 @@ 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;
+       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. */
@@ -2479,7 +2527,7 @@ int ldlm_revoke_lock_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
                             &lock->l_remote_handle, &lock->l_exp_hash);
        }
 
-        cfs_list_add_tail(&lock->l_rk_ast, rpc_list);
+       list_add_tail(&lock->l_rk_ast, rpc_list);
         LDLM_LOCK_GET(lock);
 
         unlock_res_and_lock(lock);
@@ -2488,10 +2536,10 @@ int ldlm_revoke_lock_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
 
 void ldlm_revoke_export_locks(struct obd_export *exp)
 {
-        cfs_list_t  rpc_list;
+       struct list_head  rpc_list;
         ENTRY;
 
-        CFS_INIT_LIST_HEAD(&rpc_list);
+       INIT_LIST_HEAD(&rpc_list);
         cfs_hash_for_each_empty(exp->exp_lock_hash,
                                 ldlm_revoke_lock_cb, &rpc_list);
         ldlm_run_ast_work(exp->exp_obd->obd_namespace, &rpc_list,
@@ -2502,32 +2550,52 @@ void ldlm_revoke_export_locks(struct obd_export *exp)
 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)
+static int ldlm_bl_get_work(struct ldlm_bl_pool *blp,
+                           struct ldlm_bl_work_item **p_blwi,
+                           struct obd_export **p_exp)
 {
        struct ldlm_bl_work_item *blwi = NULL;
        static unsigned int num_bl = 0;
+       static unsigned int num_stale;
+       int num_th = atomic_read(&blp->blp_num_threads);
+
+       *p_exp = obd_stale_export_get();
 
        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);
-        }
+       if (*p_exp != NULL) {
+               if (num_th == 1 || ++num_stale < num_th) {
+                       spin_unlock(&blp->blp_lock);
+                       return 1;
+               } else {
+                       num_stale = 0;
+               }
+       }
+
+       /* process a request from the blp_list at least every blp_num_threads */
+       if (!list_empty(&blp->blp_list) &&
+           (list_empty(&blp->blp_prio_list) || num_bl == 0))
+               blwi = list_entry(blp->blp_list.next,
+                                 struct ldlm_bl_work_item, blwi_entry);
+       else
+               if (!list_empty(&blp->blp_prio_list))
+                       blwi = list_entry(blp->blp_prio_list.next,
+                                         struct ldlm_bl_work_item,
+                                         blwi_entry);
+
+       if (blwi) {
+               if (++num_bl >= num_th)
+                       num_bl = 0;
+               list_del(&blwi->blwi_entry);
+       }
        spin_unlock(&blp->blp_lock);
+       *p_blwi = blwi;
 
-       return blwi;
+       if (*p_exp != NULL && *p_blwi != NULL) {
+               obd_stale_export_put(*p_exp);
+               *p_exp = NULL;
+       }
+
+       return (*p_blwi != NULL || *p_exp != NULL) ? 1 : 0;
 }
 
 /* This only contains temporary data until the thread starts */
@@ -2543,20 +2611,106 @@ 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 task_struct *task;
 
        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;
+       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;
 }
 
+/* Not fatal if racy and have a few too many threads */
+static int ldlm_bl_thread_need_create(struct ldlm_bl_pool *blp,
+                                     struct ldlm_bl_work_item *blwi)
+{
+       int busy = atomic_read(&blp->blp_busy_threads);
+
+       if (busy >= blp->blp_max_threads)
+               return 0;
+
+       if (busy < atomic_read(&blp->blp_num_threads))
+               return 0;
+
+       if (blwi != NULL && (blwi->blwi_ns == NULL ||
+                            blwi->blwi_mem_pressure))
+               return 0;
+
+       return 1;
+}
+
+static int ldlm_bl_thread_blwi(struct ldlm_bl_pool *blp,
+                              struct ldlm_bl_work_item *blwi)
+{
+       ENTRY;
+
+       if (blwi->blwi_ns == NULL)
+               /* added by ldlm_cleanup() */
+               RETURN(LDLM_ITER_STOP);
+
+       if (blwi->blwi_mem_pressure)
+               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
+                * 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,
+                                    blwi->blwi_flags);
+       } else {
+               ldlm_handle_bl_callback(blwi->blwi_ns, &blwi->blwi_ld,
+                                       blwi->blwi_lock);
+       }
+       if (blwi->blwi_mem_pressure)
+               memory_pressure_clr();
+
+       if (blwi->blwi_flags & LCF_ASYNC)
+               OBD_FREE(blwi, sizeof(*blwi));
+       else
+               complete(&blwi->blwi_comp);
+
+       RETURN(0);
+}
+
+/**
+ * Cancel stale locks on export. Cancel blocked locks first.
+ * If the given export has blocked locks, the next in the list may have
+ * them too, thus cancel not blocked locks only if the current export has
+ * no blocked locks.
+ **/
+static int ldlm_bl_thread_exports(struct ldlm_bl_pool *blp,
+                                 struct obd_export *exp)
+{
+       int num;
+       ENTRY;
+
+       OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_BL_EVICT, 4);
+
+       num = ldlm_export_cancel_blocked_locks(exp);
+       if (num == 0)
+               ldlm_export_cancel_locks(exp);
+
+       obd_stale_export_put(exp);
+
+       RETURN(0);
+}
+
+
 /**
  * Main blocking requests processing thread.
  *
@@ -2567,86 +2721,53 @@ static int ldlm_bl_thread_start(struct ldlm_bl_pool *blp)
 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;
+       atomic_inc(&blp->blp_num_threads);
+       atomic_inc(&blp->blp_busy_threads);
 
-                bltd->bltd_num =
-                        cfs_atomic_inc_return(&blp->blp_num_threads) - 1;
-                cfs_atomic_inc(&blp->blp_busy_threads);
+       complete(&bltd->bltd_comp);
+       /* cannot use bltd after this, it is only on caller's stack */
 
-                snprintf(bltd->bltd_name, sizeof(bltd->bltd_name) - 1,
-                        "ldlm_bl_%02d", bltd->bltd_num);
-                cfs_daemonize(bltd->bltd_name);
+       while (1) {
+               struct l_wait_info lwi = { 0 };
+               struct ldlm_bl_work_item *blwi = NULL;
+               struct obd_export *exp = NULL;
+               int rc;
 
-               complete(&bltd->bltd_comp);
-                /* cannot use bltd after this, it is only on caller's stack */
-        }
+               rc = ldlm_bl_get_work(blp, &blwi, &exp);
 
-        while (1) {
-                struct l_wait_info lwi = { 0 };
-                struct ldlm_bl_work_item *blwi = NULL;
-                int busy;
-
-                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 (rc == 0) {
+                       atomic_dec(&blp->blp_busy_threads);
+                       l_wait_event_exclusive(blp->blp_waitq,
+                                              ldlm_bl_get_work(blp, &blwi,
+                                                               &exp),
+                                              &lwi);
+                       atomic_inc(&blp->blp_busy_threads);
+               }
 
-                if (blwi->blwi_ns == NULL)
-                        /* added by ldlm_cleanup() */
-                        break;
+               if (ldlm_bl_thread_need_create(blp, blwi))
+                       /* 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 >= cfs_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();
-
-                if (blwi->blwi_count) {
-                        int count;
-                       /* 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);
-                } else {
-                        ldlm_handle_bl_callback(blwi->blwi_ns, &blwi->blwi_ld,
-                                                blwi->blwi_lock);
-                }
-                if (blwi->blwi_mem_pressure)
-                        cfs_memory_pressure_clr();
+               if (exp)
+                       rc = ldlm_bl_thread_exports(blp, exp);
+               else if (blwi)
+                       rc = ldlm_bl_thread_blwi(blp, blwi);
 
-                if (blwi->blwi_mode == LDLM_ASYNC)
-                        OBD_FREE(blwi, sizeof(*blwi));
-                else
-                       complete(&blwi->blwi_comp);
-        }
+               if (rc == LDLM_ITER_STOP)
+                       break;
+       }
 
-        cfs_atomic_dec(&blp->blp_busy_threads);
-        cfs_atomic_dec(&blp->blp_num_threads);
+       atomic_dec(&blp->blp_busy_threads);
+       atomic_dec(&blp->blp_num_threads);
        complete(&blp->blp_comp);
-        RETURN(0);
+       RETURN(0);
 }
 
-#endif
 
 static int ldlm_setup(void);
 static int ldlm_cleanup(void);
@@ -2665,7 +2786,6 @@ int ldlm_get_ref(void)
 
         RETURN(rc);
 }
-EXPORT_SYMBOL(ldlm_get_ref);
 
 void ldlm_put_ref(void)
 {
@@ -2684,66 +2804,65 @@ void ldlm_put_ref(void)
 
         EXIT;
 }
-EXPORT_SYMBOL(ldlm_put_ref);
 
 /*
  * Export handle<->lock hash operations.
  */
 static unsigned
-ldlm_export_lock_hash(cfs_hash_t *hs, const void *key, unsigned mask)
+ldlm_export_lock_hash(struct cfs_hash *hs, const void *key, unsigned mask)
 {
         return cfs_hash_u64_hash(((struct lustre_handle *)key)->cookie, mask);
 }
 
 static void *
-ldlm_export_lock_key(cfs_hlist_node_t *hnode)
+ldlm_export_lock_key(struct hlist_node *hnode)
 {
         struct ldlm_lock *lock;
 
-        lock = cfs_hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
+       lock = hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
         return &lock->l_remote_handle;
 }
 
 static void
-ldlm_export_lock_keycpy(cfs_hlist_node_t *hnode, void *key)
+ldlm_export_lock_keycpy(struct hlist_node *hnode, void *key)
 {
         struct ldlm_lock     *lock;
 
-        lock = cfs_hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
+       lock = hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
         lock->l_remote_handle = *(struct lustre_handle *)key;
 }
 
 static int
-ldlm_export_lock_keycmp(const void *key, cfs_hlist_node_t *hnode)
+ldlm_export_lock_keycmp(const void *key, struct hlist_node *hnode)
 {
         return lustre_handle_equal(ldlm_export_lock_key(hnode), key);
 }
 
 static void *
-ldlm_export_lock_object(cfs_hlist_node_t *hnode)
+ldlm_export_lock_object(struct hlist_node *hnode)
 {
-        return cfs_hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
+       return hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
 }
 
 static void
-ldlm_export_lock_get(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
+ldlm_export_lock_get(struct cfs_hash *hs, struct hlist_node *hnode)
 {
         struct ldlm_lock *lock;
 
-        lock = cfs_hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
+       lock = hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
         LDLM_LOCK_GET(lock);
 }
 
 static void
-ldlm_export_lock_put(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
+ldlm_export_lock_put(struct cfs_hash *hs, struct hlist_node *hnode)
 {
         struct ldlm_lock *lock;
 
-        lock = cfs_hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
+       lock = hlist_entry(hnode, struct ldlm_lock, l_exp_hash);
         LDLM_LOCK_RELEASE(lock);
 }
 
-static cfs_hash_ops_t ldlm_export_lock_ops = {
+static struct cfs_hash_ops ldlm_export_lock_ops = {
         .hs_hash        = ldlm_export_lock_hash,
         .hs_key         = ldlm_export_lock_key,
         .hs_keycmp      = ldlm_export_lock_keycmp,
@@ -2756,6 +2875,7 @@ static cfs_hash_ops_t ldlm_export_lock_ops = {
 
 int ldlm_init_export(struct obd_export *exp)
 {
+       int rc;
         ENTRY;
 
         exp->exp_lock_hash =
@@ -2771,7 +2891,14 @@ 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);
 
@@ -2789,11 +2916,13 @@ EXPORT_SYMBOL(ldlm_destroy_export);
 static int ldlm_setup(void)
 {
        static struct ptlrpc_service_conf       conf;
-       struct ldlm_bl_pool                     *blp = NULL;
-        int rc = 0;
-#ifdef __KERNEL__
-        int i;
-#endif
+       struct ldlm_bl_pool                    *blp = NULL;
+#ifdef HAVE_SERVER_SUPPORT
+       struct task_struct *task;
+#endif /* HAVE_SERVER_SUPPORT */
+       int i;
+       int rc = 0;
+
         ENTRY;
 
         if (ldlm_state != NULL)
@@ -2803,18 +2932,18 @@ static int ldlm_setup(void)
         if (ldlm_state == NULL)
                 RETURN(-ENOMEM);
 
-#ifdef LPROCFS
+#ifdef CONFIG_PROC_FS
         rc = ldlm_proc_setup();
         if (rc != 0)
                GOTO(out, rc);
-#endif
+#endif /* CONFIG_PROC_FS */
 
        memset(&conf, 0, sizeof(conf));
        conf = (typeof(conf)) {
                .psc_name               = "ldlm_cbd",
                .psc_watchdog_factor    = 2,
                .psc_buf                = {
-                       .bc_nbufs               = LDLM_NBUFS,
+                       .bc_nbufs               = LDLM_CLIENT_NBUFS,
                        .bc_buf_size            = LDLM_BUFSIZE,
                        .bc_req_max_size        = LDLM_MAXREQSIZE,
                        .bc_rep_max_size        = LDLM_MAXREPSIZE,
@@ -2853,7 +2982,7 @@ static int ldlm_setup(void)
                .psc_name               = "ldlm_canceld",
                .psc_watchdog_factor    = 6,
                .psc_buf                = {
-                       .bc_nbufs               = LDLM_NBUFS,
+                       .bc_nbufs               = LDLM_SERVER_NBUFS,
                        .bc_buf_size            = LDLM_BUFSIZE,
                        .bc_req_max_size        = LDLM_MAXREQSIZE,
                        .bc_rep_max_size        = LDLM_MAXREPSIZE,
@@ -2889,7 +3018,7 @@ static int ldlm_setup(void)
                ldlm_state->ldlm_cancel_service = NULL;
                GOTO(out, rc);
        }
-#endif
+#endif /* HAVE_SERVER_SUPPORT */
 
        OBD_ALLOC(blp, sizeof(*blp));
        if (blp == NULL)
@@ -2897,13 +3026,12 @@ static int ldlm_setup(void)
        ldlm_state->ldlm_bl_pool = blp;
 
        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);
+       INIT_LIST_HEAD(&blp->blp_list);
+       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__
        if (ldlm_num_threads == 0) {
                blp->blp_min_threads = LDLM_NTHRS_INIT;
                blp->blp_max_threads = LDLM_NTHRS_MAX;
@@ -2919,31 +3047,37 @@ static int ldlm_setup(void)
                        GOTO(out, rc);
        }
 
-# ifdef HAVE_SERVER_SUPPORT
-        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);
+#ifdef HAVE_SERVER_SUPPORT
+       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);
+       INIT_LIST_HEAD(&waiting_locks_list);
        spin_lock_init(&waiting_locks_spinlock);
-        cfs_timer_init(&waiting_locks_timer, waiting_locks_callback, 0);
+       cfs_timer_init(&waiting_locks_timer, waiting_locks_callback, NULL);
 
-        rc = cfs_create_thread(expired_lock_main, NULL, CFS_DAEMON_FLAGS);
-       if (rc < 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);
        }
 
-        cfs_wait_event(expired_lock_thread.elt_waitq,
-                       expired_lock_thread.elt_state == ELT_READY);
-# endif /* HAVE_SERVER_SUPPORT */
+       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
+
+       rc = ldlm_reclaim_setup();
+       if (rc) {
+               CERROR("Failed to setup reclaim thread: rc = %d\n", rc);
+               GOTO(out, rc);
+       }
        RETURN(0);
 
  out:
@@ -2955,28 +3089,28 @@ static int ldlm_cleanup(void)
 {
         ENTRY;
 
-        if (!cfs_list_empty(ldlm_namespace_list(LDLM_NAMESPACE_SERVER)) ||
-            !cfs_list_empty(ldlm_namespace_list(LDLM_NAMESPACE_CLIENT))) {
+       if (!list_empty(ldlm_namespace_list(LDLM_NAMESPACE_SERVER)) ||
+           !list_empty(ldlm_namespace_list(LDLM_NAMESPACE_CLIENT))) {
                 CERROR("ldlm still has namespaces; clean these up first.\n");
                 ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
                 ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
                 RETURN(-EBUSY);
         }
 
-#ifdef __KERNEL__
-        ldlm_pools_fini();
+       ldlm_reclaim_cleanup();
+       ldlm_pools_fini();
 
        if (ldlm_state->ldlm_bl_pool != NULL) {
                struct ldlm_bl_pool *blp = ldlm_state->ldlm_bl_pool;
 
-               while (cfs_atomic_read(&blp->blp_num_threads) > 0) {
+               while (atomic_read(&blp->blp_num_threads) > 0) {
                        struct ldlm_bl_work_item blwi = { .blwi_ns = NULL };
 
                        init_completion(&blp->blp_comp);
 
                        spin_lock(&blp->blp_lock);
-                       cfs_list_add_tail(&blwi.blwi_entry, &blp->blp_list);
-                       cfs_waitq_signal(&blp->blp_waitq);
+                       list_add_tail(&blwi.blwi_entry, &blp->blp_list);
+                       wake_up(&blp->blp_waitq);
                        spin_unlock(&blp->blp_lock);
 
                        wait_for_completion(&blp->blp_comp);
@@ -2984,27 +3118,24 @@ static int ldlm_cleanup(void)
 
                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
+#ifdef HAVE_SERVER_SUPPORT
        if (ldlm_state->ldlm_cancel_service != NULL)
                ptlrpc_unregister_service(ldlm_state->ldlm_cancel_service);
-# endif
+#endif
 
-#ifdef __KERNEL__
        ldlm_proc_cleanup();
 
-# ifdef HAVE_SERVER_SUPPORT
+#ifdef HAVE_SERVER_SUPPORT
        if (expired_lock_thread.elt_state != ELT_STOPPED) {
                expired_lock_thread.elt_state = ELT_TERMINATE;
-               cfs_waitq_signal(&expired_lock_thread.elt_waitq);
-               cfs_wait_event(expired_lock_thread.elt_waitq,
+               wake_up(&expired_lock_thread.elt_waitq);
+               wait_event(expired_lock_thread.elt_waitq,
                               expired_lock_thread.elt_state == ELT_STOPPED);
        }
-# endif
-#endif /* __KERNEL__ */
+#endif
 
         OBD_FREE(ldlm_state, sizeof(*ldlm_state));
         ldlm_state = NULL;
@@ -3017,49 +3148,60 @@ int ldlm_init(void)
        mutex_init(&ldlm_ref_mutex);
        mutex_init(ldlm_namespace_lock(LDLM_NAMESPACE_SERVER));
        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 | SLAB_DESTROY_BY_RCU);
-       if (ldlm_lock_slab == NULL) {
-               cfs_mem_cache_destroy(ldlm_resource_slab);
+       INIT_LIST_HEAD(&ldlm_srv_namespace_list);
+       INIT_LIST_HEAD(&ldlm_cli_active_namespace_list);
+       INIT_LIST_HEAD(&ldlm_cli_inactive_namespace_list);
+
+       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_interval_slab = cfs_mem_cache_create("interval_node",
+       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)
+               goto out_resource;
+
+       ldlm_interval_slab = kmem_cache_create("interval_node",
                                         sizeof(struct ldlm_interval),
-                                        0, CFS_SLAB_HWCACHE_ALIGN);
-        if (ldlm_interval_slab == NULL) {
-                cfs_mem_cache_destroy(ldlm_resource_slab);
-                cfs_mem_cache_destroy(ldlm_lock_slab);
-                return -ENOMEM;
-        }
+                                       0, SLAB_HWCACHE_ALIGN, NULL);
+       if (ldlm_interval_slab == NULL)
+               goto out_lock;
+
+       ldlm_interval_tree_slab = kmem_cache_create("interval_tree",
+                       sizeof(struct ldlm_interval_tree) * LCK_MODE_NUM,
+                       0, SLAB_HWCACHE_ALIGN, NULL);
+       if (ldlm_interval_tree_slab == NULL)
+               goto out_interval;
+
 #if LUSTRE_TRACKS_LOCK_EXP_REFS
-        class_export_dump_hook = ldlm_dump_export_locks;
+       class_export_dump_hook = ldlm_dump_export_locks;
 #endif
-        return 0;
+       return 0;
+
+out_interval:
+       kmem_cache_destroy(ldlm_interval_slab);
+out_lock:
+       kmem_cache_destroy(ldlm_lock_slab);
+out_resource:
+       kmem_cache_destroy(ldlm_resource_slab);
+
+       return -ENOMEM;
 }
 
 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");
-#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();
-#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");
+       if (ldlm_refcount)
+               CERROR("ldlm_refcount is %d in ldlm_exit!\n", ldlm_refcount);
+       kmem_cache_destroy(ldlm_resource_slab);
+       /* 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();
+       kmem_cache_destroy(ldlm_lock_slab);
+       kmem_cache_destroy(ldlm_interval_slab);
+       kmem_cache_destroy(ldlm_interval_tree_slab);
 }