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LU-3086 build: fix 'uninitialized variables' errors
[fs/lustre-release.git] / lustre / osc / osc_request.c
index 404bca2..4092d93 100644 (file)
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 /*
  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  */
 
-#ifndef EXPORT_SYMTAB
-# define EXPORT_SYMTAB
-#endif
 #define DEBUG_SUBSYSTEM S_OSC
 
 #include <libcfs/libcfs.h>
 #include <lustre_log.h>
 #include <lustre_debug.h>
 #include <lustre_param.h>
+#include <lustre_fid.h>
 #include "osc_internal.h"
-
-static quota_interface_t *quota_interface = NULL;
-extern quota_interface_t osc_quota_interface;
+#include "osc_cl_internal.h"
 
 static void osc_release_ppga(struct brw_page **ppga, obd_count count);
 static int brw_interpret(const struct lu_env *env,
@@ -73,92 +69,95 @@ int osc_cleanup(struct obd_device *obd);
 
 /* Pack OSC object metadata for disk storage (LE byte order). */
 static int osc_packmd(struct obd_export *exp, struct lov_mds_md **lmmp,
-                      struct lov_stripe_md *lsm)
+                     struct lov_stripe_md *lsm)
 {
-        int lmm_size;
-        ENTRY;
+       int lmm_size;
+       ENTRY;
 
-        lmm_size = sizeof(**lmmp);
-        if (!lmmp)
-                RETURN(lmm_size);
+       lmm_size = sizeof(**lmmp);
+       if (lmmp == NULL)
+               RETURN(lmm_size);
 
-        if (*lmmp && !lsm) {
-                OBD_FREE(*lmmp, lmm_size);
-                *lmmp = NULL;
-                RETURN(0);
-        }
+       if (*lmmp != NULL && lsm == NULL) {
+               OBD_FREE(*lmmp, lmm_size);
+               *lmmp = NULL;
+               RETURN(0);
+       } else if (unlikely(lsm != NULL && ostid_id(&lsm->lsm_oi) == 0)) {
+               RETURN(-EBADF);
+       }
 
-        if (!*lmmp) {
-                OBD_ALLOC(*lmmp, lmm_size);
-                if (!*lmmp)
-                        RETURN(-ENOMEM);
-        }
+       if (*lmmp == NULL) {
+               OBD_ALLOC(*lmmp, lmm_size);
+               if (*lmmp == NULL)
+                       RETURN(-ENOMEM);
+       }
 
-        if (lsm) {
-                LASSERT(lsm->lsm_object_id);
-                LASSERT_SEQ_IS_MDT(lsm->lsm_object_seq);
-                (*lmmp)->lmm_object_id = cpu_to_le64(lsm->lsm_object_id);
-                (*lmmp)->lmm_object_seq = cpu_to_le64(lsm->lsm_object_seq);
-        }
+       if (lsm)
+               ostid_cpu_to_le(&lsm->lsm_oi, &(*lmmp)->lmm_oi);
 
-        RETURN(lmm_size);
+       RETURN(lmm_size);
 }
 
 /* Unpack OSC object metadata from disk storage (LE byte order). */
 static int osc_unpackmd(struct obd_export *exp, struct lov_stripe_md **lsmp,
-                        struct lov_mds_md *lmm, int lmm_bytes)
-{
-        int lsm_size;
-        ENTRY;
-
-        if (lmm != NULL) {
-                if (lmm_bytes < sizeof (*lmm)) {
-                        CERROR("lov_mds_md too small: %d, need %d\n",
-                               lmm_bytes, (int)sizeof(*lmm));
-                        RETURN(-EINVAL);
-                }
-                /* XXX LOV_MAGIC etc check? */
-
-                if (lmm->lmm_object_id == 0) {
-                        CERROR("lov_mds_md: zero lmm_object_id\n");
-                        RETURN(-EINVAL);
-                }
-        }
-
-        lsm_size = lov_stripe_md_size(1);
-        if (lsmp == NULL)
-                RETURN(lsm_size);
-
-        if (*lsmp != NULL && lmm == NULL) {
-                OBD_FREE((*lsmp)->lsm_oinfo[0], sizeof(struct lov_oinfo));
-                OBD_FREE(*lsmp, lsm_size);
-                *lsmp = NULL;
-                RETURN(0);
-        }
-
-        if (*lsmp == NULL) {
-                OBD_ALLOC(*lsmp, lsm_size);
-                if (*lsmp == NULL)
-                        RETURN(-ENOMEM);
-                OBD_ALLOC((*lsmp)->lsm_oinfo[0], sizeof(struct lov_oinfo));
-                if ((*lsmp)->lsm_oinfo[0] == NULL) {
-                        OBD_FREE(*lsmp, lsm_size);
-                        RETURN(-ENOMEM);
-                }
-                loi_init((*lsmp)->lsm_oinfo[0]);
-        }
-
-        if (lmm != NULL) {
-                /* XXX zero *lsmp? */
-                (*lsmp)->lsm_object_id = le64_to_cpu (lmm->lmm_object_id);
-                (*lsmp)->lsm_object_seq = le64_to_cpu (lmm->lmm_object_seq);
-                LASSERT((*lsmp)->lsm_object_id);
-                LASSERT_SEQ_IS_MDT((*lsmp)->lsm_object_seq);
-        }
-
-        (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES;
-
-        RETURN(lsm_size);
+                       struct lov_mds_md *lmm, int lmm_bytes)
+{
+       int lsm_size;
+       struct obd_import *imp = class_exp2cliimp(exp);
+       ENTRY;
+
+       if (lmm != NULL) {
+               if (lmm_bytes < sizeof(*lmm)) {
+                       CERROR("%s: lov_mds_md too small: %d, need %d\n",
+                              exp->exp_obd->obd_name, lmm_bytes,
+                              (int)sizeof(*lmm));
+                       RETURN(-EINVAL);
+               }
+               /* XXX LOV_MAGIC etc check? */
+
+               if (unlikely(ostid_id(&lmm->lmm_oi) == 0)) {
+                       CERROR("%s: zero lmm_object_id: rc = %d\n",
+                              exp->exp_obd->obd_name, -EINVAL);
+                       RETURN(-EINVAL);
+               }
+       }
+
+       lsm_size = lov_stripe_md_size(1);
+       if (lsmp == NULL)
+               RETURN(lsm_size);
+
+       if (*lsmp != NULL && lmm == NULL) {
+               OBD_FREE((*lsmp)->lsm_oinfo[0], sizeof(struct lov_oinfo));
+               OBD_FREE(*lsmp, lsm_size);
+               *lsmp = NULL;
+               RETURN(0);
+       }
+
+       if (*lsmp == NULL) {
+               OBD_ALLOC(*lsmp, lsm_size);
+               if (unlikely(*lsmp == NULL))
+                       RETURN(-ENOMEM);
+               OBD_ALLOC((*lsmp)->lsm_oinfo[0], sizeof(struct lov_oinfo));
+               if (unlikely((*lsmp)->lsm_oinfo[0] == NULL)) {
+                       OBD_FREE(*lsmp, lsm_size);
+                       RETURN(-ENOMEM);
+               }
+               loi_init((*lsmp)->lsm_oinfo[0]);
+       } else if (unlikely(ostid_id(&(*lsmp)->lsm_oi) == 0)) {
+               RETURN(-EBADF);
+       }
+
+       if (lmm != NULL)
+               /* XXX zero *lsmp? */
+               ostid_le_to_cpu(&lmm->lmm_oi, &(*lsmp)->lsm_oi);
+
+       if (imp != NULL &&
+           (imp->imp_connect_data.ocd_connect_flags & OBD_CONNECT_MAXBYTES))
+               (*lsmp)->lsm_maxbytes = imp->imp_connect_data.ocd_maxbytes;
+       else
+               (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES;
+
+       RETURN(lsm_size);
 }
 
 static inline void osc_pack_capa(struct ptlrpc_request *req,
@@ -215,9 +214,9 @@ static int osc_getattr_interpret(const struct lu_env *env,
                 CDEBUG(D_INODE, "mode: %o\n", body->oa.o_mode);
                 lustre_get_wire_obdo(aa->aa_oi->oi_oa, &body->oa);
 
-                /* This should really be sent by the OST */
-                aa->aa_oi->oi_oa->o_blksize = PTLRPC_MAX_BRW_SIZE;
-                aa->aa_oi->oi_oa->o_valid |= OBD_MD_FLBLKSZ;
+               /* This should really be sent by the OST */
+               aa->aa_oi->oi_oa->o_blksize = DT_MAX_BRW_SIZE;
+               aa->aa_oi->oi_oa->o_valid |= OBD_MD_FLBLKSZ;
         } else {
                 CDEBUG(D_INFO, "can't unpack ost_body\n");
                 rc = -EPROTO;
@@ -260,7 +259,8 @@ static int osc_getattr_async(struct obd_export *exp, struct obd_info *oinfo,
         RETURN(0);
 }
 
-static int osc_getattr(struct obd_export *exp, struct obd_info *oinfo)
+static int osc_getattr(const struct lu_env *env, struct obd_export *exp,
+                       struct obd_info *oinfo)
 {
         struct ptlrpc_request *req;
         struct ost_body       *body;
@@ -293,9 +293,8 @@ static int osc_getattr(struct obd_export *exp, struct obd_info *oinfo)
         CDEBUG(D_INODE, "mode: %o\n", body->oa.o_mode);
         lustre_get_wire_obdo(oinfo->oi_oa, &body->oa);
 
-        /* This should really be sent by the OST */
-        oinfo->oi_oa->o_blksize = PTLRPC_MAX_BRW_SIZE;
-        oinfo->oi_oa->o_valid |= OBD_MD_FLBLKSZ;
+       oinfo->oi_oa->o_blksize = cli_brw_size(exp->exp_obd);
+       oinfo->oi_oa->o_valid |= OBD_MD_FLBLKSZ;
 
         EXIT;
  out:
@@ -303,8 +302,8 @@ static int osc_getattr(struct obd_export *exp, struct obd_info *oinfo)
         return rc;
 }
 
-static int osc_setattr(struct obd_export *exp, struct obd_info *oinfo,
-                       struct obd_trans_info *oti)
+static int osc_setattr(const struct lu_env *env, struct obd_export *exp,
+                       struct obd_info *oinfo, struct obd_trans_info *oti)
 {
         struct ptlrpc_request *req;
         struct ost_body       *body;
@@ -395,7 +394,7 @@ int osc_setattr_async_base(struct obd_export *exp, struct obd_info *oinfo,
         /* do mds to ost setattr asynchronously */
         if (!rqset) {
                 /* Do not wait for response. */
-                ptlrpcd_add_req(req, PSCOPE_OTHER);
+                ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
         } else {
                 req->rq_interpret_reply =
                         (ptlrpc_interpterer_t)osc_setattr_interpret;
@@ -407,7 +406,7 @@ int osc_setattr_async_base(struct obd_export *exp, struct obd_info *oinfo,
                 sa->sa_cookie = cookie;
 
                 if (rqset == PTLRPCD_SET)
-                        ptlrpcd_add_req(req, PSCOPE_OTHER);
+                        ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
                 else
                         ptlrpc_set_add_req(rqset, req);
         }
@@ -476,17 +475,15 @@ int osc_real_create(struct obd_export *exp, struct obdo *oa,
 
         lustre_get_wire_obdo(oa, &body->oa);
 
-        /* This should really be sent by the OST */
-        oa->o_blksize = PTLRPC_MAX_BRW_SIZE;
-        oa->o_valid |= OBD_MD_FLBLKSZ;
+       oa->o_blksize = cli_brw_size(exp->exp_obd);
+       oa->o_valid |= OBD_MD_FLBLKSZ;
 
-        /* XXX LOV STACKING: the lsm that is passed to us from LOV does not
-         * have valid lsm_oinfo data structs, so don't go touching that.
-         * This needs to be fixed in a big way.
-         */
-        lsm->lsm_object_id = oa->o_id;
-        lsm->lsm_object_seq = oa->o_seq;
-        *ea = lsm;
+       /* XXX LOV STACKING: the lsm that is passed to us from LOV does not
+        * have valid lsm_oinfo data structs, so don't go touching that.
+        * This needs to be fixed in a big way.
+        */
+       lsm->lsm_oi = oa->o_oi;
+       *ea = lsm;
 
         if (oti != NULL) {
                 oti->oti_transno = lustre_msg_get_transno(req->rq_repmsg);
@@ -538,7 +535,6 @@ int osc_punch_base(struct obd_export *exp, struct obd_info *oinfo,
 
         ptlrpc_request_set_replen(req);
 
-
         req->rq_interpret_reply = (ptlrpc_interpterer_t)osc_setattr_interpret;
         CLASSERT (sizeof(*sa) <= sizeof(req->rq_async_args));
         sa = ptlrpc_req_async_args(req);
@@ -546,15 +542,15 @@ int osc_punch_base(struct obd_export *exp, struct obd_info *oinfo,
         sa->sa_upcall = upcall;
         sa->sa_cookie = cookie;
         if (rqset == PTLRPCD_SET)
-                ptlrpcd_add_req(req, PSCOPE_OTHER);
+                ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
         else
                 ptlrpc_set_add_req(rqset, req);
 
         RETURN(0);
 }
 
-static int osc_punch(struct obd_export *exp, struct obd_info *oinfo,
-                     struct obd_trans_info *oti,
+static int osc_punch(const struct lu_env *env, struct obd_export *exp,
+                     struct obd_info *oinfo, struct obd_trans_info *oti,
                      struct ptlrpc_request_set *rqset)
 {
         oinfo->oi_oa->o_size   = oinfo->oi_policy.l_extent.start;
@@ -564,25 +560,44 @@ static int osc_punch(struct obd_export *exp, struct obd_info *oinfo,
                               oinfo->oi_cb_up, oinfo, rqset);
 }
 
-static int osc_sync(struct obd_export *exp, struct obdo *oa,
-                    struct lov_stripe_md *md, obd_size start, obd_size end,
-                    void *capa)
+static int osc_sync_interpret(const struct lu_env *env,
+                              struct ptlrpc_request *req,
+                              void *arg, int rc)
 {
-        struct ptlrpc_request *req;
-        struct ost_body       *body;
-        int                    rc;
+       struct osc_fsync_args *fa = arg;
+        struct ost_body *body;
         ENTRY;
 
-        if (!oa) {
-                CDEBUG(D_INFO, "oa NULL\n");
-                RETURN(-EINVAL);
+        if (rc)
+                GOTO(out, rc);
+
+        body = req_capsule_server_get(&req->rq_pill, &RMF_OST_BODY);
+        if (body == NULL) {
+                CERROR ("can't unpack ost_body\n");
+                GOTO(out, rc = -EPROTO);
         }
 
+       *fa->fa_oi->oi_oa = body->oa;
+out:
+       rc = fa->fa_upcall(fa->fa_cookie, rc);
+       RETURN(rc);
+}
+
+int osc_sync_base(struct obd_export *exp, struct obd_info *oinfo,
+                 obd_enqueue_update_f upcall, void *cookie,
+                  struct ptlrpc_request_set *rqset)
+{
+       struct ptlrpc_request *req;
+       struct ost_body       *body;
+       struct osc_fsync_args *fa;
+        int                    rc;
+        ENTRY;
+
         req = ptlrpc_request_alloc(class_exp2cliimp(exp), &RQF_OST_SYNC);
         if (req == NULL)
                 RETURN(-ENOMEM);
 
-        osc_set_capa_size(req, &RMF_CAPA1, capa);
+        osc_set_capa_size(req, &RMF_CAPA1, oinfo->oi_capa);
         rc = ptlrpc_request_pack(req, LUSTRE_OST_VERSION, OST_SYNC);
         if (rc) {
                 ptlrpc_request_free(req);
@@ -592,28 +607,42 @@ static int osc_sync(struct obd_export *exp, struct obdo *oa,
         /* overload the size and blocks fields in the oa with start/end */
         body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
         LASSERT(body);
-        lustre_set_wire_obdo(&body->oa, oa);
-        body->oa.o_size = start;
-        body->oa.o_blocks = end;
-        body->oa.o_valid |= (OBD_MD_FLSIZE | OBD_MD_FLBLOCKS);
-        osc_pack_capa(req, body, capa);
+        lustre_set_wire_obdo(&body->oa, oinfo->oi_oa);
+        osc_pack_capa(req, body, oinfo->oi_capa);
 
         ptlrpc_request_set_replen(req);
+        req->rq_interpret_reply = osc_sync_interpret;
 
-        rc = ptlrpc_queue_wait(req);
-        if (rc)
-                GOTO(out, rc);
+       CLASSERT(sizeof(*fa) <= sizeof(req->rq_async_args));
+       fa = ptlrpc_req_async_args(req);
+       fa->fa_oi = oinfo;
+       fa->fa_upcall = upcall;
+       fa->fa_cookie = cookie;
 
-        body = req_capsule_server_get(&req->rq_pill, &RMF_OST_BODY);
-        if (body == NULL)
-                GOTO(out, rc = -EPROTO);
+       if (rqset == PTLRPCD_SET)
+               ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
+       else
+               ptlrpc_set_add_req(rqset, req);
 
-        lustre_get_wire_obdo(oa, &body->oa);
+       RETURN (0);
+}
 
-        EXIT;
- out:
-        ptlrpc_req_finished(req);
-        return rc;
+static int osc_sync(const struct lu_env *env, struct obd_export *exp,
+                   struct obd_info *oinfo, obd_size start, obd_size end,
+                   struct ptlrpc_request_set *set)
+{
+       ENTRY;
+
+       if (!oinfo->oi_oa) {
+               CDEBUG(D_INFO, "oa NULL\n");
+               RETURN(-EINVAL);
+       }
+
+       oinfo->oi_oa->o_size = start;
+       oinfo->oi_oa->o_blocks = end;
+       oinfo->oi_oa->o_valid |= (OBD_MD_FLSIZE | OBD_MD_FLBLOCKS);
+
+       RETURN(osc_sync_base(exp, oinfo, oinfo->oi_cb_up, oinfo, set));
 }
 
 /* Find and cancel locally locks matched by @mode in the resource found by
@@ -629,10 +658,19 @@ static int osc_resource_get_unused(struct obd_export *exp, struct obdo *oa,
         int count;
         ENTRY;
 
-        osc_build_res_name(oa->o_id, oa->o_seq, &res_id);
-        res = ldlm_resource_get(ns, NULL, &res_id, 0, 0);
-        if (res == NULL)
-                RETURN(0);
+       /* Return, i.e. cancel nothing, only if ELC is supported (flag in
+        * export) but disabled through procfs (flag in NS).
+        *
+        * This distinguishes from a case when ELC is not supported originally,
+        * when we still want to cancel locks in advance and just cancel them
+        * locally, without sending any RPC. */
+       if (exp_connect_cancelset(exp) && !ns_connect_cancelset(ns))
+               RETURN(0);
+
+       ostid_build_res_name(&oa->o_oi, &res_id);
+       res = ldlm_resource_get(ns, NULL, &res_id, 0, 0);
+       if (res == NULL)
+               RETURN(0);
 
         LDLM_RESOURCE_ADDREF(res);
         count = ldlm_cancel_resource_local(res, cancels, NULL, mode,
@@ -671,6 +709,31 @@ static int osc_can_send_destroy(struct client_obd *cli)
         return 0;
 }
 
+int osc_create(const struct lu_env *env, struct obd_export *exp,
+              struct obdo *oa, struct lov_stripe_md **ea,
+              struct obd_trans_info *oti)
+{
+       int rc = 0;
+       ENTRY;
+
+       LASSERT(oa);
+       LASSERT(ea);
+       LASSERT(oa->o_valid & OBD_MD_FLGROUP);
+
+       if ((oa->o_valid & OBD_MD_FLFLAGS) &&
+           oa->o_flags == OBD_FL_RECREATE_OBJS) {
+               RETURN(osc_real_create(exp, oa, ea, oti));
+       }
+
+       if (!fid_seq_is_mdt(ostid_seq(&oa->o_oi)))
+               RETURN(osc_real_create(exp, oa, ea, oti));
+
+       /* we should not get here anymore */
+       LBUG();
+
+       RETURN(rc);
+}
+
 /* Destroy requests can be async always on the client, and we don't even really
  * care about the return code since the client cannot do anything at all about
  * a destroy failure.
@@ -681,9 +744,10 @@ static int osc_can_send_destroy(struct client_obd *cli)
  * the records are not cancelled, and when the OST reconnects to the MDS next,
  * it will retrieve the llog unlink logs and then sends the log cancellation
  * cookies to the MDS after committing destroy transactions. */
-static int osc_destroy(struct obd_export *exp, struct obdo *oa,
-                       struct lov_stripe_md *ea, struct obd_trans_info *oti,
-                       struct obd_export *md_export, void *capa)
+static int osc_destroy(const struct lu_env *env, struct obd_export *exp,
+                       struct obdo *oa, struct lov_stripe_md *ea,
+                       struct obd_trans_info *oti, struct obd_export *md_export,
+                       void *capa)
 {
         struct client_obd     *cli = &exp->exp_obd->u.cli;
         struct ptlrpc_request *req;
@@ -726,8 +790,11 @@ static int osc_destroy(struct obd_export *exp, struct obdo *oa,
         osc_pack_capa(req, body, (struct obd_capa *)capa);
         ptlrpc_request_set_replen(req);
 
-        /* don't throttle destroy RPCs for the MDT */
-        if (!(cli->cl_import->imp_connect_flags_orig & OBD_CONNECT_MDS)) {
+       /* If osc_destory is for destroying the unlink orphan,
+        * sent from MDT to OST, which should not be blocked here,
+        * because the process might be triggered by ptlrpcd, and
+        * it is not good to block ptlrpcd thread (b=16006)*/
+       if (!(oa->o_flags & OBD_FL_DELORPHAN)) {
                 req->rq_interpret_reply = osc_destroy_interpret;
                 if (!osc_can_send_destroy(cli)) {
                         struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP,
@@ -743,7 +810,7 @@ static int osc_destroy(struct obd_export *exp, struct obdo *oa,
         }
 
         /* Do not wait for response */
-        ptlrpcd_add_req(req, PSCOPE_OTHER);
+        ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
         RETURN(0);
 }
 
@@ -757,31 +824,36 @@ static void osc_announce_cached(struct client_obd *cli, struct obdo *oa,
         oa->o_valid |= bits;
         client_obd_list_lock(&cli->cl_loi_list_lock);
         oa->o_dirty = cli->cl_dirty;
-        if (cli->cl_dirty - cli->cl_dirty_transit > cli->cl_dirty_max) {
-                CERROR("dirty %lu - %lu > dirty_max %lu\n",
-                       cli->cl_dirty, cli->cl_dirty_transit, cli->cl_dirty_max);
-                oa->o_undirty = 0;
-        } else if (cfs_atomic_read(&obd_dirty_pages) -
-                   cfs_atomic_read(&obd_dirty_transit_pages) >
-                   obd_max_dirty_pages + 1){
-                /* The cfs_atomic_read() allowing the cfs_atomic_inc() are
-                 * not covered by a lock thus they may safely race and trip
-                 * this CERROR() unless we add in a small fudge factor (+1). */
-                CERROR("dirty %d - %d > system dirty_max %d\n",
-                       cfs_atomic_read(&obd_dirty_pages),
-                       cfs_atomic_read(&obd_dirty_transit_pages),
-                       obd_max_dirty_pages);
-                oa->o_undirty = 0;
-        } else if (cli->cl_dirty_max - cli->cl_dirty > 0x7fffffff) {
-                CERROR("dirty %lu - dirty_max %lu too big???\n",
-                       cli->cl_dirty, cli->cl_dirty_max);
-                oa->o_undirty = 0;
-        } else {
-                long max_in_flight = (cli->cl_max_pages_per_rpc << CFS_PAGE_SHIFT)*
-                                (cli->cl_max_rpcs_in_flight + 1);
+       if (unlikely(cli->cl_dirty - cli->cl_dirty_transit >
+                    cli->cl_dirty_max)) {
+               CERROR("dirty %lu - %lu > dirty_max %lu\n",
+                      cli->cl_dirty, cli->cl_dirty_transit, cli->cl_dirty_max);
+               oa->o_undirty = 0;
+       } else if (unlikely(cfs_atomic_read(&obd_unstable_pages) +
+                           cfs_atomic_read(&obd_dirty_pages) -
+                           cfs_atomic_read(&obd_dirty_transit_pages) >
+                           (long)(obd_max_dirty_pages + 1))) {
+               /* The cfs_atomic_read() allowing the cfs_atomic_inc() are
+                * not covered by a lock thus they may safely race and trip
+                * this CERROR() unless we add in a small fudge factor (+1). */
+               CERROR("%s: dirty %d + %d - %d > system dirty_max %d\n",
+                      cli->cl_import->imp_obd->obd_name,
+                      cfs_atomic_read(&obd_unstable_pages),
+                      cfs_atomic_read(&obd_dirty_pages),
+                      cfs_atomic_read(&obd_dirty_transit_pages),
+                      obd_max_dirty_pages);
+               oa->o_undirty = 0;
+       } else if (unlikely(cli->cl_dirty_max - cli->cl_dirty > 0x7fffffff)) {
+               CERROR("dirty %lu - dirty_max %lu too big???\n",
+                      cli->cl_dirty, cli->cl_dirty_max);
+               oa->o_undirty = 0;
+       } else {
+               long max_in_flight = (cli->cl_max_pages_per_rpc <<
+                                     CFS_PAGE_SHIFT)*
+                                    (cli->cl_max_rpcs_in_flight + 1);
                 oa->o_undirty = max(cli->cl_dirty_max, max_in_flight);
         }
-        oa->o_grant = cli->cl_avail_grant;
+       oa->o_grant = cli->cl_avail_grant + cli->cl_reserved_grant;
         oa->o_dropped = cli->cl_lost_grant;
         cli->cl_lost_grant = 0;
         client_obd_list_unlock(&cli->cl_loi_list_lock);
@@ -790,7 +862,7 @@ static void osc_announce_cached(struct client_obd *cli, struct obdo *oa,
 
 }
 
-static void osc_update_next_shrink(struct client_obd *cli)
+void osc_update_next_shrink(struct client_obd *cli)
 {
         cli->cl_next_shrink_grant =
                 cfs_time_shift(cli->cl_grant_shrink_interval);
@@ -798,115 +870,6 @@ static void osc_update_next_shrink(struct client_obd *cli)
                cli->cl_next_shrink_grant);
 }
 
-/* caller must hold loi_list_lock */
-static void osc_consume_write_grant(struct client_obd *cli,
-                                    struct brw_page *pga)
-{
-        LASSERT_SPIN_LOCKED(&cli->cl_loi_list_lock.lock);
-        LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
-        cfs_atomic_inc(&obd_dirty_pages);
-        cli->cl_dirty += CFS_PAGE_SIZE;
-        cli->cl_avail_grant -= CFS_PAGE_SIZE;
-        pga->flag |= OBD_BRW_FROM_GRANT;
-        CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
-               CFS_PAGE_SIZE, pga, pga->pg);
-        LASSERT(cli->cl_avail_grant >= 0);
-        osc_update_next_shrink(cli);
-}
-
-/* the companion to osc_consume_write_grant, called when a brw has completed.
- * must be called with the loi lock held. */
-static void osc_release_write_grant(struct client_obd *cli,
-                                    struct brw_page *pga, int sent)
-{
-        int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
-        ENTRY;
-
-        LASSERT_SPIN_LOCKED(&cli->cl_loi_list_lock.lock);
-        if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
-                EXIT;
-                return;
-        }
-
-        pga->flag &= ~OBD_BRW_FROM_GRANT;
-        cfs_atomic_dec(&obd_dirty_pages);
-        cli->cl_dirty -= CFS_PAGE_SIZE;
-        if (pga->flag & OBD_BRW_NOCACHE) {
-                pga->flag &= ~OBD_BRW_NOCACHE;
-                cfs_atomic_dec(&obd_dirty_transit_pages);
-                cli->cl_dirty_transit -= CFS_PAGE_SIZE;
-        }
-        if (!sent) {
-                cli->cl_lost_grant += CFS_PAGE_SIZE;
-                CDEBUG(D_CACHE, "lost grant: %lu avail grant: %lu dirty: %lu\n",
-                       cli->cl_lost_grant, cli->cl_avail_grant, cli->cl_dirty);
-        } else if (CFS_PAGE_SIZE != blocksize && pga->count != CFS_PAGE_SIZE) {
-                /* For short writes we shouldn't count parts of pages that
-                 * span a whole block on the OST side, or our accounting goes
-                 * wrong.  Should match the code in filter_grant_check. */
-                int offset = pga->off & ~CFS_PAGE_MASK;
-                int count = pga->count + (offset & (blocksize - 1));
-                int end = (offset + pga->count) & (blocksize - 1);
-                if (end)
-                        count += blocksize - end;
-
-                cli->cl_lost_grant += CFS_PAGE_SIZE - count;
-                CDEBUG(D_CACHE, "lost %lu grant: %lu avail: %lu dirty: %lu\n",
-                       CFS_PAGE_SIZE - count, cli->cl_lost_grant,
-                       cli->cl_avail_grant, cli->cl_dirty);
-        }
-
-        EXIT;
-}
-
-static unsigned long rpcs_in_flight(struct client_obd *cli)
-{
-        return cli->cl_r_in_flight + cli->cl_w_in_flight;
-}
-
-/* caller must hold loi_list_lock */
-void osc_wake_cache_waiters(struct client_obd *cli)
-{
-        cfs_list_t *l, *tmp;
-        struct osc_cache_waiter *ocw;
-
-        ENTRY;
-        cfs_list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
-                /* if we can't dirty more, we must wait until some is written */
-                if ((cli->cl_dirty + CFS_PAGE_SIZE > cli->cl_dirty_max) ||
-                   (cfs_atomic_read(&obd_dirty_pages) + 1 >
-                    obd_max_dirty_pages)) {
-                        CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
-                               "osc max %ld, sys max %d\n", cli->cl_dirty,
-                               cli->cl_dirty_max, obd_max_dirty_pages);
-                        return;
-                }
-
-                /* if still dirty cache but no grant wait for pending RPCs that
-                 * may yet return us some grant before doing sync writes */
-                if (cli->cl_w_in_flight && cli->cl_avail_grant < CFS_PAGE_SIZE) {
-                        CDEBUG(D_CACHE, "%u BRW writes in flight, no grant\n",
-                               cli->cl_w_in_flight);
-                        return;
-                }
-
-                ocw = cfs_list_entry(l, struct osc_cache_waiter, ocw_entry);
-                cfs_list_del_init(&ocw->ocw_entry);
-                if (cli->cl_avail_grant < CFS_PAGE_SIZE) {
-                        /* no more RPCs in flight to return grant, do sync IO */
-                        ocw->ocw_rc = -EDQUOT;
-                        CDEBUG(D_INODE, "wake oap %p for sync\n", ocw->ocw_oap);
-                } else {
-                        osc_consume_write_grant(cli,
-                                                &ocw->ocw_oap->oap_brw_page);
-                }
-
-                cfs_waitq_signal(&ocw->ocw_waitq);
-        }
-
-        EXIT;
-}
-
 static void __osc_update_grant(struct client_obd *cli, obd_size grant)
 {
         client_obd_list_lock(&cli->cl_loi_list_lock);
@@ -922,9 +885,9 @@ static void osc_update_grant(struct client_obd *cli, struct ost_body *body)
         }
 }
 
-static int osc_set_info_async(struct obd_export *exp, obd_count keylen,
-                              void *key, obd_count vallen, void *val,
-                              struct ptlrpc_request_set *set);
+static int osc_set_info_async(const struct lu_env *env, struct obd_export *exp,
+                              obd_count keylen, void *key, obd_count vallen,
+                              void *val, struct ptlrpc_request_set *set);
 
 static int osc_shrink_grant_interpret(const struct lu_env *env,
                                       struct ptlrpc_request *req,
@@ -953,6 +916,10 @@ static void osc_shrink_grant_local(struct client_obd *cli, struct obdo *oa)
         oa->o_grant = cli->cl_avail_grant / 4;
         cli->cl_avail_grant -= oa->o_grant;
         client_obd_list_unlock(&cli->cl_loi_list_lock);
+        if (!(oa->o_valid & OBD_MD_FLFLAGS)) {
+                oa->o_valid |= OBD_MD_FLFLAGS;
+                oa->o_flags = 0;
+        }
         oa->o_flags |= OBD_FL_SHRINK_GRANT;
         osc_update_next_shrink(cli);
 }
@@ -963,50 +930,54 @@ static void osc_shrink_grant_local(struct client_obd *cli, struct obdo *oa)
  * needed, and avoids shrinking the grant piecemeal. */
 static int osc_shrink_grant(struct client_obd *cli)
 {
-        long target = (cli->cl_max_rpcs_in_flight + 1) *
-                      cli->cl_max_pages_per_rpc;
+       __u64 target_bytes = (cli->cl_max_rpcs_in_flight + 1) *
+                            (cli->cl_max_pages_per_rpc << CFS_PAGE_SHIFT);
 
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-        if (cli->cl_avail_grant <= target)
-                target = cli->cl_max_pages_per_rpc;
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
+       client_obd_list_lock(&cli->cl_loi_list_lock);
+       if (cli->cl_avail_grant <= target_bytes)
+               target_bytes = cli->cl_max_pages_per_rpc << CFS_PAGE_SHIFT;
+       client_obd_list_unlock(&cli->cl_loi_list_lock);
 
-        return osc_shrink_grant_to_target(cli, target);
+       return osc_shrink_grant_to_target(cli, target_bytes);
 }
 
-int osc_shrink_grant_to_target(struct client_obd *cli, long target)
+int osc_shrink_grant_to_target(struct client_obd *cli, __u64 target_bytes)
 {
-        int    rc = 0;
-        struct ost_body     *body;
-        ENTRY;
+       int                     rc = 0;
+       struct ost_body        *body;
+       ENTRY;
 
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-        /* Don't shrink if we are already above or below the desired limit
-         * We don't want to shrink below a single RPC, as that will negatively
-         * impact block allocation and long-term performance. */
-        if (target < cli->cl_max_pages_per_rpc)
-                target = cli->cl_max_pages_per_rpc;
+       client_obd_list_lock(&cli->cl_loi_list_lock);
+       /* Don't shrink if we are already above or below the desired limit
+        * We don't want to shrink below a single RPC, as that will negatively
+        * impact block allocation and long-term performance. */
+       if (target_bytes < cli->cl_max_pages_per_rpc << CFS_PAGE_SHIFT)
+               target_bytes = cli->cl_max_pages_per_rpc << CFS_PAGE_SHIFT;
 
-        if (target >= cli->cl_avail_grant) {
-                client_obd_list_unlock(&cli->cl_loi_list_lock);
-                RETURN(0);
-        }
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
+       if (target_bytes >= cli->cl_avail_grant) {
+               client_obd_list_unlock(&cli->cl_loi_list_lock);
+               RETURN(0);
+       }
+       client_obd_list_unlock(&cli->cl_loi_list_lock);
 
-        OBD_ALLOC_PTR(body);
-        if (!body)
-                RETURN(-ENOMEM);
+       OBD_ALLOC_PTR(body);
+       if (!body)
+               RETURN(-ENOMEM);
 
-        osc_announce_cached(cli, &body->oa, 0);
+       osc_announce_cached(cli, &body->oa, 0);
 
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-        body->oa.o_grant = cli->cl_avail_grant - target;
-        cli->cl_avail_grant = target;
+       client_obd_list_lock(&cli->cl_loi_list_lock);
+       body->oa.o_grant = cli->cl_avail_grant - target_bytes;
+       cli->cl_avail_grant = target_bytes;
         client_obd_list_unlock(&cli->cl_loi_list_lock);
+        if (!(body->oa.o_valid & OBD_MD_FLFLAGS)) {
+                body->oa.o_valid |= OBD_MD_FLFLAGS;
+                body->oa.o_flags = 0;
+        }
         body->oa.o_flags |= OBD_FL_SHRINK_GRANT;
         osc_update_next_shrink(cli);
 
-        rc = osc_set_info_async(cli->cl_import->imp_obd->obd_self_export,
+        rc = osc_set_info_async(NULL, cli->cl_import->imp_obd->obd_self_export,
                                 sizeof(KEY_GRANT_SHRINK), KEY_GRANT_SHRINK,
                                 sizeof(*body), body, NULL);
         if (rc != 0)
@@ -1015,7 +986,6 @@ int osc_shrink_grant_to_target(struct client_obd *cli, long target)
         RETURN(rc);
 }
 
-#define GRANT_SHRINK_LIMIT PTLRPC_MAX_BRW_SIZE
 static int osc_should_shrink_grant(struct client_obd *client)
 {
         cfs_time_t time = cfs_time_current();
@@ -1025,13 +995,18 @@ static int osc_should_shrink_grant(struct client_obd *client)
              OBD_CONNECT_GRANT_SHRINK) == 0)
                 return 0;
 
-        if (cfs_time_aftereq(time, next_shrink - 5 * CFS_TICK)) {
-                if (client->cl_import->imp_state == LUSTRE_IMP_FULL &&
-                    client->cl_avail_grant > GRANT_SHRINK_LIMIT)
-                        return 1;
-                else
-                        osc_update_next_shrink(client);
-        }
+       if (cfs_time_aftereq(time, next_shrink - 5 * CFS_TICK)) {
+               /* Get the current RPC size directly, instead of going via:
+                * cli_brw_size(obd->u.cli.cl_import->imp_obd->obd_self_export)
+                * Keep comment here so that it can be found by searching. */
+               int brw_size = client->cl_max_pages_per_rpc << CFS_PAGE_SHIFT;
+
+               if (client->cl_import->imp_state == LUSTRE_IMP_FULL &&
+                   client->cl_avail_grant > brw_size)
+                       return 1;
+               else
+                       osc_update_next_shrink(client);
+       }
         return 0;
 }
 
@@ -1089,23 +1064,25 @@ static void osc_init_grant(struct client_obd *cli, struct obd_connect_data *ocd)
                 cli->cl_avail_grant = ocd->ocd_grant - cli->cl_dirty;
 
         if (cli->cl_avail_grant < 0) {
-                CWARN("%s: available grant < 0, the OSS is probably not running"
-                      " with patch from bug20278 (%ld) \n",
-                      cli->cl_import->imp_obd->obd_name, cli->cl_avail_grant);
-                /* workaround for 1.6 servers which do not have 
-                 * the patch from bug20278 */
-                cli->cl_avail_grant = ocd->ocd_grant;
+               CWARN("%s: available grant < 0: avail/ocd/dirty %ld/%u/%ld\n",
+                     cli->cl_import->imp_obd->obd_name, cli->cl_avail_grant,
+                     ocd->ocd_grant, cli->cl_dirty);
+               /* workaround for servers which do not have the patch from
+                * LU-2679 */
+               cli->cl_avail_grant = ocd->ocd_grant;
         }
 
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
+       /* determine the appropriate chunk size used by osc_extent. */
+       cli->cl_chunkbits = max_t(int, CFS_PAGE_SHIFT, ocd->ocd_blocksize);
+       client_obd_list_unlock(&cli->cl_loi_list_lock);
 
-        CDEBUG(D_CACHE, "%s, setting cl_avail_grant: %ld cl_lost_grant: %ld \n",
-               cli->cl_import->imp_obd->obd_name,
-               cli->cl_avail_grant, cli->cl_lost_grant);
+       CDEBUG(D_CACHE, "%s, setting cl_avail_grant: %ld cl_lost_grant: %ld."
+               "chunk bits: %d.\n", cli->cl_import->imp_obd->obd_name,
+               cli->cl_avail_grant, cli->cl_lost_grant, cli->cl_chunkbits);
 
-        if (ocd->ocd_connect_flags & OBD_CONNECT_GRANT_SHRINK &&
-            cfs_list_empty(&cli->cl_grant_shrink_list))
-                osc_add_shrink_grant(cli);
+       if (ocd->ocd_connect_flags & OBD_CONNECT_GRANT_SHRINK &&
+           cfs_list_empty(&cli->cl_grant_shrink_list))
+               osc_add_shrink_grant(cli);
 }
 
 /* We assume that the reason this OSC got a short read is because it read
@@ -1164,7 +1141,7 @@ static int check_write_rcs(struct ptlrpc_request *req,
 
         /* return error if any niobuf was in error */
         for (i = 0; i < niocount; i++) {
-                if (remote_rcs[i] < 0)
+                if ((int)remote_rcs[i] < 0)
                         return(remote_rcs[i]);
 
                 if (remote_rcs[i] != 0) {
@@ -1186,14 +1163,16 @@ static int check_write_rcs(struct ptlrpc_request *req,
 static inline int can_merge_pages(struct brw_page *p1, struct brw_page *p2)
 {
         if (p1->flag != p2->flag) {
-                unsigned mask = ~(OBD_BRW_FROM_GRANT|
-                                  OBD_BRW_NOCACHE|OBD_BRW_SYNC|OBD_BRW_ASYNC);
+                unsigned mask = ~(OBD_BRW_FROM_GRANT| OBD_BRW_NOCACHE|
+                                  OBD_BRW_SYNC|OBD_BRW_ASYNC|OBD_BRW_NOQUOTA);
 
                 /* warn if we try to combine flags that we don't know to be
                  * safe to combine */
-                if ((p1->flag & mask) != (p2->flag & mask))
-                        CERROR("is it ok to have flags 0x%x and 0x%x in the "
-                               "same brw?\n", p1->flag, p2->flag);
+                if (unlikely((p1->flag & mask) != (p2->flag & mask))) {
+                        CWARN("Saw flags 0x%x and 0x%x in the same brw, please "
+                              "report this at http://bugs.whamcloud.com/\n",
+                              p1->flag, p2->flag);
+                }
                 return 0;
         }
 
@@ -1201,46 +1180,68 @@ static inline int can_merge_pages(struct brw_page *p1, struct brw_page *p2)
 }
 
 static obd_count osc_checksum_bulk(int nob, obd_count pg_count,
-                                   struct brw_page **pga, int opc,
-                                   cksum_type_t cksum_type)
-{
-        __u32 cksum;
-        int i = 0;
-
-        LASSERT (pg_count > 0);
-        cksum = init_checksum(cksum_type);
-        while (nob > 0 && pg_count > 0) {
-                unsigned char *ptr = cfs_kmap(pga[i]->pg);
-                int off = pga[i]->off & ~CFS_PAGE_MASK;
-                int count = pga[i]->count > nob ? nob : pga[i]->count;
-
-                /* corrupt the data before we compute the checksum, to
-                 * simulate an OST->client data error */
-                if (i == 0 && opc == OST_READ &&
-                    OBD_FAIL_CHECK(OBD_FAIL_OSC_CHECKSUM_RECEIVE))
-                        memcpy(ptr + off, "bad1", min(4, nob));
-                cksum = compute_checksum(cksum, ptr + off, count, cksum_type);
-                cfs_kunmap(pga[i]->pg);
-                LL_CDEBUG_PAGE(D_PAGE, pga[i]->pg, "off %d checksum %x\n",
-                               off, cksum);
-
-                nob -= pga[i]->count;
-                pg_count--;
-                i++;
-        }
-        /* For sending we only compute the wrong checksum instead
-         * of corrupting the data so it is still correct on a redo */
-        if (opc == OST_WRITE && OBD_FAIL_CHECK(OBD_FAIL_OSC_CHECKSUM_SEND))
-                cksum++;
-
-        return cksum;
+                                  struct brw_page **pga, int opc,
+                                  cksum_type_t cksum_type)
+{
+       __u32                           cksum;
+       int                             i = 0;
+       struct cfs_crypto_hash_desc     *hdesc;
+       unsigned int                    bufsize;
+       int                             err;
+       unsigned char                   cfs_alg = cksum_obd2cfs(cksum_type);
+
+       LASSERT(pg_count > 0);
+
+       hdesc = cfs_crypto_hash_init(cfs_alg, NULL, 0);
+       if (IS_ERR(hdesc)) {
+               CERROR("Unable to initialize checksum hash %s\n",
+                      cfs_crypto_hash_name(cfs_alg));
+               return PTR_ERR(hdesc);
+       }
+
+       while (nob > 0 && pg_count > 0) {
+               int count = pga[i]->count > nob ? nob : pga[i]->count;
+
+               /* corrupt the data before we compute the checksum, to
+                * simulate an OST->client data error */
+               if (i == 0 && opc == OST_READ &&
+                   OBD_FAIL_CHECK(OBD_FAIL_OSC_CHECKSUM_RECEIVE)) {
+                       unsigned char *ptr = cfs_kmap(pga[i]->pg);
+                       int off = pga[i]->off & ~CFS_PAGE_MASK;
+                       memcpy(ptr + off, "bad1", min(4, nob));
+                       cfs_kunmap(pga[i]->pg);
+               }
+               cfs_crypto_hash_update_page(hdesc, pga[i]->pg,
+                                 pga[i]->off & ~CFS_PAGE_MASK,
+                                 count);
+               LL_CDEBUG_PAGE(D_PAGE, pga[i]->pg, "off %d\n",
+                              (int)(pga[i]->off & ~CFS_PAGE_MASK));
+
+               nob -= pga[i]->count;
+               pg_count--;
+               i++;
+       }
+
+       bufsize = 4;
+       err = cfs_crypto_hash_final(hdesc, (unsigned char *)&cksum, &bufsize);
+
+       if (err)
+               cfs_crypto_hash_final(hdesc, NULL, NULL);
+
+       /* For sending we only compute the wrong checksum instead
+        * of corrupting the data so it is still correct on a redo */
+       if (opc == OST_WRITE && OBD_FAIL_CHECK(OBD_FAIL_OSC_CHECKSUM_SEND))
+               cksum++;
+
+       return cksum;
 }
 
 static int osc_brw_prep_request(int cmd, struct client_obd *cli,struct obdo *oa,
                                 struct lov_stripe_md *lsm, obd_count page_count,
                                 struct brw_page **pga,
                                 struct ptlrpc_request **reqp,
-                                struct obd_capa *ocapa, int reserve)
+                                struct obd_capa *ocapa, int reserve,
+                                int resend)
 {
         struct ptlrpc_request   *req;
         struct ptlrpc_bulk_desc *desc;
@@ -1289,13 +1290,14 @@ static int osc_brw_prep_request(int cmd, struct client_obd *cli,struct obdo *oa,
         }
         req->rq_request_portal = OST_IO_PORTAL; /* bug 7198 */
         ptlrpc_at_set_req_timeout(req);
+       /* ask ptlrpc not to resend on EINPROGRESS since BRWs have their own
+        * retry logic */
+       req->rq_no_retry_einprogress = 1;
 
-        if (opc == OST_WRITE)
-                desc = ptlrpc_prep_bulk_imp(req, page_count,
-                                            BULK_GET_SOURCE, OST_BULK_PORTAL);
-        else
-                desc = ptlrpc_prep_bulk_imp(req, page_count,
-                                            BULK_PUT_SINK, OST_BULK_PORTAL);
+       desc = ptlrpc_prep_bulk_imp(req, page_count,
+               cli->cl_import->imp_connect_data.ocd_brw_size >> LNET_MTU_BITS,
+               opc == OST_WRITE ? BULK_GET_SOURCE : BULK_PUT_SINK,
+               OST_BULK_PORTAL);
 
         if (desc == NULL)
                 GOTO(out, rc = -ENOMEM);
@@ -1308,18 +1310,30 @@ static int osc_brw_prep_request(int cmd, struct client_obd *cli,struct obdo *oa,
 
         lustre_set_wire_obdo(&body->oa, oa);
 
-        obdo_to_ioobj(oa, ioobj);
-        ioobj->ioo_bufcnt = niocount;
-        osc_pack_capa(req, body, ocapa);
-        LASSERT (page_count > 0);
-        pg_prev = pga[0];
+       obdo_to_ioobj(oa, ioobj);
+       ioobj->ioo_bufcnt = niocount;
+       /* The high bits of ioo_max_brw tells server _maximum_ number of bulks
+        * that might be send for this request.  The actual number is decided
+        * when the RPC is finally sent in ptlrpc_register_bulk(). It sends
+        * "max - 1" for old client compatibility sending "0", and also so the
+        * the actual maximum is a power-of-two number, not one less. LU-1431 */
+       ioobj_max_brw_set(ioobj, desc->bd_md_max_brw);
+       osc_pack_capa(req, body, ocapa);
+       LASSERT(page_count > 0);
+       pg_prev = pga[0];
         for (requested_nob = i = 0; i < page_count; i++, niobuf++) {
                 struct brw_page *pg = pga[i];
+                int poff = pg->off & ~CFS_PAGE_MASK;
 
                 LASSERT(pg->count > 0);
-                LASSERTF((pg->off & ~CFS_PAGE_MASK) + pg->count <= CFS_PAGE_SIZE,
-                         "i: %d pg: %p off: "LPU64", count: %u\n", i, pg,
-                         pg->off, pg->count);
+                /* make sure there is no gap in the middle of page array */
+                LASSERTF(page_count == 1 ||
+                         (ergo(i == 0, poff + pg->count == CFS_PAGE_SIZE) &&
+                          ergo(i > 0 && i < page_count - 1,
+                               poff == 0 && pg->count == CFS_PAGE_SIZE)   &&
+                          ergo(i == page_count - 1, poff == 0)),
+                         "i: %d/%d pg: %p off: "LPU64", count: %u\n",
+                         i, page_count, pg, pg->off, pg->count);
 #ifdef __linux__
                 LASSERTF(i == 0 || pg->off > pg_prev->off,
                          "i %d p_c %u pg %p [pri %lu ind %lu] off "LPU64
@@ -1335,8 +1349,7 @@ static int osc_brw_prep_request(int cmd, struct client_obd *cli,struct obdo *oa,
                 LASSERT((pga[0]->flag & OBD_BRW_SRVLOCK) ==
                         (pg->flag & OBD_BRW_SRVLOCK));
 
-                ptlrpc_prep_bulk_page(desc, pg->pg, pg->off & ~CFS_PAGE_MASK,
-                                      pg->count);
+               ptlrpc_prep_bulk_page_pin(desc, pg->pg, poff, pg->count);
                 requested_nob += pg->count;
 
                 if (i > 0 && can_merge_pages(pg_prev, pg)) {
@@ -1356,12 +1369,20 @@ static int osc_brw_prep_request(int cmd, struct client_obd *cli,struct obdo *oa,
                 &RMF_NIOBUF_REMOTE), (void *)(niobuf - niocount));
 
         osc_announce_cached(cli, &body->oa, opc == OST_WRITE ? requested_nob:0);
+        if (resend) {
+                if ((body->oa.o_valid & OBD_MD_FLFLAGS) == 0) {
+                        body->oa.o_valid |= OBD_MD_FLFLAGS;
+                        body->oa.o_flags = 0;
+                }
+                body->oa.o_flags |= OBD_FL_RECOV_RESEND;
+        }
+
         if (osc_should_shrink_grant(cli))
                 osc_shrink_grant_local(cli, &body->oa);
 
         /* size[REQ_REC_OFF] still sizeof (*body) */
         if (opc == OST_WRITE) {
-                if (unlikely(cli->cl_checksum) &&
+                if (cli->cl_checksum &&
                     !sptlrpc_flavor_has_bulk(&req->rq_flvr)) {
                         /* store cl_cksum_type in a local variable since
                          * it can be changed via lprocfs */
@@ -1392,7 +1413,7 @@ static int osc_brw_prep_request(int cmd, struct client_obd *cli,struct obdo *oa,
                 req_capsule_set_size(pill, &RMF_RCS, RCL_SERVER,
                                      sizeof(__u32) * niocount);
         } else {
-                if (unlikely(cli->cl_checksum) &&
+                if (cli->cl_checksum &&
                     !sptlrpc_flavor_has_bulk(&req->rq_flvr)) {
                         if ((body->oa.o_valid & OBD_MD_FLFLAGS) == 0)
                                 body->oa.o_flags = 0;
@@ -1437,15 +1458,8 @@ static int check_write_checksum(struct obdo *oa, const lnet_process_id_t *peer,
                 return 0;
         }
 
-        /* If this is mmaped file - it can be changed at any time */
-        if (oa->o_valid & OBD_MD_FLFLAGS && oa->o_flags & OBD_FL_MMAP)
-                return 1;
-
-        if (oa->o_valid & OBD_MD_FLFLAGS)
-                cksum_type = cksum_type_unpack(oa->o_flags);
-        else
-                cksum_type = OBD_CKSUM_CRC32;
-
+        cksum_type = cksum_type_unpack(oa->o_valid & OBD_MD_FLFLAGS ?
+                                       oa->o_flags : 0);
         new_cksum = osc_checksum_bulk(nob, page_count, pga, OST_WRITE,
                                       cksum_type);
 
@@ -1461,20 +1475,18 @@ static int check_write_checksum(struct obdo *oa, const lnet_process_id_t *peer,
                 msg = "changed in transit AND doesn't match the original - "
                       "likely false positive due to mmap IO (bug 11742)";
 
-        LCONSOLE_ERROR_MSG(0x132, "BAD WRITE CHECKSUM: %s: from %s inode "DFID
-                           " object "LPU64"/"LPU64" extent ["LPU64"-"LPU64"]\n",
-                           msg, libcfs_nid2str(peer->nid),
-                           oa->o_valid & OBD_MD_FLFID ? oa->o_parent_seq : (__u64)0,
-                           oa->o_valid & OBD_MD_FLFID ? oa->o_parent_oid : 0,
-                           oa->o_valid & OBD_MD_FLFID ? oa->o_parent_ver : 0,
-                           oa->o_id,
-                           oa->o_valid & OBD_MD_FLGROUP ? oa->o_seq : (__u64)0,
-                           pga[0]->off,
-                           pga[page_count-1]->off + pga[page_count-1]->count - 1);
-        CERROR("original client csum %x (type %x), server csum %x (type %x), "
-               "client csum now %x\n", client_cksum, client_cksum_type,
-               server_cksum, cksum_type, new_cksum);
-        return 1;
+       LCONSOLE_ERROR_MSG(0x132, "BAD WRITE CHECKSUM: %s: from %s inode "DFID
+                          " object "DOSTID" extent ["LPU64"-"LPU64"]\n",
+                          msg, libcfs_nid2str(peer->nid),
+                          oa->o_valid & OBD_MD_FLFID ? oa->o_parent_seq : (__u64)0,
+                          oa->o_valid & OBD_MD_FLFID ? oa->o_parent_oid : 0,
+                          oa->o_valid & OBD_MD_FLFID ? oa->o_parent_ver : 0,
+                          POSTID(&oa->o_oi), pga[0]->off,
+                          pga[page_count-1]->off + pga[page_count-1]->count - 1);
+       CERROR("original client csum %x (type %x), server csum %x (type %x), "
+              "client csum now %x\n", client_cksum, client_cksum_type,
+              server_cksum, cksum_type, new_cksum);
+       return 1;
 }
 
 /* Note rc enters this function as number of bytes transferred */
@@ -1500,7 +1512,6 @@ static int osc_brw_fini_request(struct ptlrpc_request *req, int rc)
                 RETURN(-EPROTO);
         }
 
-#ifdef HAVE_QUOTA_SUPPORT
         /* set/clear over quota flag for a uid/gid */
         if (lustre_msg_get_opc(req->rq_reqmsg) == OST_WRITE &&
             body->oa.o_valid & (OBD_MD_FLUSRQUOTA | OBD_MD_FLGRPQUOTA)) {
@@ -1509,10 +1520,8 @@ static int osc_brw_fini_request(struct ptlrpc_request *req, int rc)
                 CDEBUG(D_QUOTA, "setdq for [%u %u] with valid "LPX64", flags %x\n",
                        body->oa.o_uid, body->oa.o_gid, body->oa.o_valid,
                        body->oa.o_flags);
-                lquota_setdq(quota_interface, cli, qid, body->oa.o_valid,
-                             body->oa.o_flags);
+                osc_quota_setdq(cli, qid, body->oa.o_valid, body->oa.o_flags);
         }
-#endif
 
         osc_update_grant(cli, body);
 
@@ -1573,10 +1582,8 @@ static int osc_brw_fini_request(struct ptlrpc_request *req, int rc)
                 char      *router;
                 cksum_type_t cksum_type;
 
-                if (body->oa.o_valid & OBD_MD_FLFLAGS)
-                        cksum_type = cksum_type_unpack(body->oa.o_flags);
-                else
-                        cksum_type = OBD_CKSUM_CRC32;
+                cksum_type = cksum_type_unpack(body->oa.o_valid &OBD_MD_FLFLAGS?
+                                               body->oa.o_flags : 0);
                 client_cksum = osc_checksum_bulk(rc, aa->aa_page_count,
                                                  aa->aa_ppga, OST_READ,
                                                  cksum_type);
@@ -1588,42 +1595,39 @@ static int osc_brw_fini_request(struct ptlrpc_request *req, int rc)
                         router = libcfs_nid2str(req->rq_bulk->bd_sender);
                 }
 
-                if (server_cksum == ~0 && rc > 0) {
-                        CERROR("Protocol error: server %s set the 'checksum' "
-                               "bit, but didn't send a checksum.  Not fatal, "
-                               "but please notify on http://bugzilla.lustre.org/\n",
-                               libcfs_nid2str(peer->nid));
-                } else if (server_cksum != client_cksum) {
-                        LCONSOLE_ERROR_MSG(0x133, "%s: BAD READ CHECKSUM: from "
-                                           "%s%s%s inode "DFID" object "
-                                           LPU64"/"LPU64" extent "
-                                           "["LPU64"-"LPU64"]\n",
-                                           req->rq_import->imp_obd->obd_name,
-                                           libcfs_nid2str(peer->nid),
-                                           via, router,
-                                           body->oa.o_valid & OBD_MD_FLFID ?
-                                                body->oa.o_parent_seq : (__u64)0,
-                                           body->oa.o_valid & OBD_MD_FLFID ?
-                                                body->oa.o_parent_oid : 0,
-                                           body->oa.o_valid & OBD_MD_FLFID ?
-                                                body->oa.o_parent_ver : 0,
-                                           body->oa.o_id,
-                                           body->oa.o_valid & OBD_MD_FLGROUP ?
-                                                body->oa.o_seq : (__u64)0,
-                                           aa->aa_ppga[0]->off,
-                                           aa->aa_ppga[aa->aa_page_count-1]->off +
-                                           aa->aa_ppga[aa->aa_page_count-1]->count -
-                                                                        1);
-                        CERROR("client %x, server %x, cksum_type %x\n",
-                               client_cksum, server_cksum, cksum_type);
-                        cksum_counter = 0;
-                        aa->aa_oa->o_cksum = client_cksum;
-                        rc = -EAGAIN;
-                } else {
-                        cksum_counter++;
-                        CDEBUG(D_PAGE, "checksum %x confirmed\n", client_cksum);
-                        rc = 0;
-                }
+               if (server_cksum == ~0 && rc > 0) {
+                       CERROR("Protocol error: server %s set the 'checksum' "
+                              "bit, but didn't send a checksum.  Not fatal, "
+                              "but please notify on http://bugs.whamcloud.com/\n",
+                              libcfs_nid2str(peer->nid));
+               } else if (server_cksum != client_cksum) {
+                       LCONSOLE_ERROR_MSG(0x133, "%s: BAD READ CHECKSUM: from "
+                                          "%s%s%s inode "DFID" object "DOSTID
+                                          " extent ["LPU64"-"LPU64"]\n",
+                                          req->rq_import->imp_obd->obd_name,
+                                          libcfs_nid2str(peer->nid),
+                                          via, router,
+                                          body->oa.o_valid & OBD_MD_FLFID ?
+                                               body->oa.o_parent_seq : (__u64)0,
+                                          body->oa.o_valid & OBD_MD_FLFID ?
+                                               body->oa.o_parent_oid : 0,
+                                          body->oa.o_valid & OBD_MD_FLFID ?
+                                               body->oa.o_parent_ver : 0,
+                                          POSTID(&body->oa.o_oi),
+                                          aa->aa_ppga[0]->off,
+                                          aa->aa_ppga[aa->aa_page_count-1]->off +
+                                          aa->aa_ppga[aa->aa_page_count-1]->count -
+                                                                       1);
+                       CERROR("client %x, server %x, cksum_type %x\n",
+                              client_cksum, server_cksum, cksum_type);
+                       cksum_counter = 0;
+                       aa->aa_oa->o_cksum = client_cksum;
+                       rc = -EAGAIN;
+               } else {
+                       cksum_counter++;
+                       CDEBUG(D_PAGE, "checksum %x confirmed\n", client_cksum);
+                       rc = 0;
+               }
         } else if (unlikely(client_cksum)) {
                 static int cksum_missed;
 
@@ -1649,19 +1653,26 @@ static int osc_brw_internal(int cmd, struct obd_export *exp, struct obdo *oa,
         struct ptlrpc_request *req;
         int                    rc;
         cfs_waitq_t            waitq;
-        int                    resends = 0;
+        int                    generation, resends = 0;
         struct l_wait_info     lwi;
 
         ENTRY;
 
         cfs_waitq_init(&waitq);
+        generation = exp->exp_obd->u.cli.cl_import->imp_generation;
 
 restart_bulk:
         rc = osc_brw_prep_request(cmd, &exp->exp_obd->u.cli, oa, lsm,
-                                  page_count, pga, &req, ocapa, 0);
+                                  page_count, pga, &req, ocapa, 0, resends);
         if (rc != 0)
                 return (rc);
 
+        if (resends) {
+                req->rq_generation_set = 1;
+                req->rq_import_generation = generation;
+                req->rq_sent = cfs_time_current_sec() + resends;
+        }
+
         rc = ptlrpc_queue_wait(req);
 
         if (rc == -ETIMEDOUT && req->rq_resend) {
@@ -1673,57 +1684,63 @@ restart_bulk:
         rc = osc_brw_fini_request(req, rc);
 
         ptlrpc_req_finished(req);
+        /* When server return -EINPROGRESS, client should always retry
+         * regardless of the number of times the bulk was resent already.*/
         if (osc_recoverable_error(rc)) {
                 resends++;
-                if (!osc_should_resend(resends, &exp->exp_obd->u.cli)) {
-                        CERROR("too many resend retries, returning error\n");
-                        RETURN(-EIO);
+                if (rc != -EINPROGRESS &&
+                    !client_should_resend(resends, &exp->exp_obd->u.cli)) {
+                        CERROR("%s: too many resend retries for object: "
+                               ""DOSTID", rc = %d.\n", exp->exp_obd->obd_name,
+                              POSTID(&oa->o_oi), rc);
+                        goto out;
                 }
-
-                lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(resends), NULL, NULL, NULL);
+               if (generation !=
+                   exp->exp_obd->u.cli.cl_import->imp_generation) {
+                       CDEBUG(D_HA, "%s: resend cross eviction for object: "
+                              ""DOSTID", rc = %d.\n", exp->exp_obd->obd_name,
+                              POSTID(&oa->o_oi), rc);
+                       goto out;
+               }
+
+                lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(resends), NULL, NULL,
+                                       NULL);
                 l_wait_event(waitq, 0, &lwi);
 
                 goto restart_bulk;
         }
-
+out:
+        if (rc == -EAGAIN || rc == -EINPROGRESS)
+                rc = -EIO;
         RETURN (rc);
 }
 
-int osc_brw_redo_request(struct ptlrpc_request *request,
-                         struct osc_brw_async_args *aa)
+static int osc_brw_redo_request(struct ptlrpc_request *request,
+                               struct osc_brw_async_args *aa, int rc)
 {
         struct ptlrpc_request *new_req;
-        struct ptlrpc_request_set *set = request->rq_set;
         struct osc_brw_async_args *new_aa;
         struct osc_async_page *oap;
-        int rc = 0;
         ENTRY;
 
-        if (!osc_should_resend(aa->aa_resends, aa->aa_cli)) {
-                CERROR("too many resent retries, returning error\n");
-                RETURN(-EIO);
-        }
-
-        DEBUG_REQ(D_ERROR, request, "redo for recoverable error");
+       DEBUG_REQ(rc == -EINPROGRESS ? D_RPCTRACE : D_ERROR, request,
+                 "redo for recoverable error %d", rc);
 
         rc = osc_brw_prep_request(lustre_msg_get_opc(request->rq_reqmsg) ==
                                         OST_WRITE ? OBD_BRW_WRITE :OBD_BRW_READ,
                                   aa->aa_cli, aa->aa_oa,
                                   NULL /* lsm unused by osc currently */,
                                   aa->aa_page_count, aa->aa_ppga,
-                                  &new_req, aa->aa_ocapa, 0);
+                                  &new_req, aa->aa_ocapa, 0, 1);
         if (rc)
                 RETURN(rc);
 
-        client_obd_list_lock(&aa->aa_cli->cl_loi_list_lock);
-
         cfs_list_for_each_entry(oap, &aa->aa_oaps, oap_rpc_item) {
                 if (oap->oap_request != NULL) {
                         LASSERTF(request == oap->oap_request,
                                  "request %p != oap_request %p\n",
                                  request, oap->oap_request);
                         if (oap->oap_interrupted) {
-                                client_obd_list_unlock(&aa->aa_cli->cl_loi_list_lock);
                                 ptlrpc_req_finished(new_req);
                                 RETURN(-EINTR);
                         }
@@ -1734,13 +1751,23 @@ int osc_brw_redo_request(struct ptlrpc_request *request,
         aa->aa_resends++;
         new_req->rq_interpret_reply = request->rq_interpret_reply;
         new_req->rq_async_args = request->rq_async_args;
-        new_req->rq_sent = cfs_time_current_sec() + aa->aa_resends;
+       new_req->rq_commit_cb = request->rq_commit_cb;
+       /* cap resend delay to the current request timeout, this is similar to
+        * what ptlrpc does (see after_reply()) */
+       if (aa->aa_resends > new_req->rq_timeout)
+               new_req->rq_sent = cfs_time_current_sec() + new_req->rq_timeout;
+       else
+               new_req->rq_sent = cfs_time_current_sec() + aa->aa_resends;
+        new_req->rq_generation_set = 1;
+        new_req->rq_import_generation = request->rq_import_generation;
 
         new_aa = ptlrpc_req_async_args(new_req);
 
         CFS_INIT_LIST_HEAD(&new_aa->aa_oaps);
-        cfs_list_splice(&aa->aa_oaps, &new_aa->aa_oaps);
-        CFS_INIT_LIST_HEAD(&aa->aa_oaps);
+       cfs_list_splice_init(&aa->aa_oaps, &new_aa->aa_oaps);
+       CFS_INIT_LIST_HEAD(&new_aa->aa_exts);
+       cfs_list_splice_init(&aa->aa_exts, &new_aa->aa_exts);
+       new_aa->aa_resends = aa->aa_resends;
 
         cfs_list_for_each_entry(oap, &new_aa->aa_oaps, oap_rpc_item) {
                 if (oap->oap_request) {
@@ -1752,16 +1779,14 @@ int osc_brw_redo_request(struct ptlrpc_request *request,
         new_aa->aa_ocapa = aa->aa_ocapa;
         aa->aa_ocapa = NULL;
 
-        /* use ptlrpc_set_add_req is safe because interpret functions work
-         * in check_set context. only one way exist with access to request
-         * from different thread got -EINTR - this way protected with
-         * cl_loi_list_lock */
-        ptlrpc_set_add_req(set, new_req);
+       /* XXX: This code will run into problem if we're going to support
+        * to add a series of BRW RPCs into a self-defined ptlrpc_request_set
+        * and wait for all of them to be finished. We should inherit request
+        * set from old request. */
+       ptlrpcd_add_req(new_req, PDL_POLICY_SAME, -1);
 
-        client_obd_list_unlock(&aa->aa_cli->cl_loi_list_lock);
-
-        DEBUG_REQ(D_INFO, new_req, "new request");
-        RETURN(0);
+       DEBUG_REQ(D_INFO, new_req, "new request");
+       RETURN(0);
 }
 
 /*
@@ -1915,1228 +1940,372 @@ out:
         RETURN(rc);
 }
 
-/* The companion to osc_enter_cache(), called when @oap is no longer part of
- * the dirty accounting.  Writeback completes or truncate happens before
- * writing starts.  Must be called with the loi lock held. */
-static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap,
-                           int sent)
-{
-        osc_release_write_grant(cli, &oap->oap_brw_page, sent);
-}
-
-
-/* This maintains the lists of pending pages to read/write for a given object
- * (lop).  This is used by osc_check_rpcs->osc_next_loi() and loi_list_maint()
- * to quickly find objects that are ready to send an RPC. */
-static int lop_makes_rpc(struct client_obd *cli, struct loi_oap_pages *lop,
-                         int cmd)
+static int brw_interpret(const struct lu_env *env,
+                         struct ptlrpc_request *req, void *data, int rc)
 {
-        int optimal;
+       struct osc_brw_async_args *aa = data;
+       struct osc_extent *ext;
+       struct osc_extent *tmp;
+       struct cl_object  *obj = NULL;
+       struct client_obd *cli = aa->aa_cli;
         ENTRY;
 
-        if (lop->lop_num_pending == 0)
-                RETURN(0);
-
-        /* if we have an invalid import we want to drain the queued pages
-         * by forcing them through rpcs that immediately fail and complete
-         * the pages.  recovery relies on this to empty the queued pages
-         * before canceling the locks and evicting down the llite pages */
-        if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
-                RETURN(1);
+        rc = osc_brw_fini_request(req, rc);
+        CDEBUG(D_INODE, "request %p aa %p rc %d\n", req, aa, rc);
+        /* When server return -EINPROGRESS, client should always retry
+         * regardless of the number of times the bulk was resent already. */
+       if (osc_recoverable_error(rc)) {
+               if (req->rq_import_generation !=
+                   req->rq_import->imp_generation) {
+                       CDEBUG(D_HA, "%s: resend cross eviction for object: "
+                              ""DOSTID", rc = %d.\n",
+                              req->rq_import->imp_obd->obd_name,
+                              POSTID(&aa->aa_oa->o_oi), rc);
+               } else if (rc == -EINPROGRESS ||
+                   client_should_resend(aa->aa_resends, aa->aa_cli)) {
+                       rc = osc_brw_redo_request(req, aa, rc);
+               } else {
+                       CERROR("%s: too many resent retries for object: "
+                              ""LPU64":"LPU64", rc = %d.\n",
+                              req->rq_import->imp_obd->obd_name,
+                              POSTID(&aa->aa_oa->o_oi), rc);
+               }
+
+               if (rc == 0)
+                       RETURN(0);
+               else if (rc == -EAGAIN || rc == -EINPROGRESS)
+                       rc = -EIO;
+       }
 
-        /* stream rpcs in queue order as long as as there is an urgent page
-         * queued.  this is our cheap solution for good batching in the case
-         * where writepage marks some random page in the middle of the file
-         * as urgent because of, say, memory pressure */
-        if (!cfs_list_empty(&lop->lop_urgent)) {
-                CDEBUG(D_CACHE, "urgent request forcing RPC\n");
-                RETURN(1);
-        }
-        /* fire off rpcs when we have 'optimal' rpcs as tuned for the wire. */
-        optimal = cli->cl_max_pages_per_rpc;
-        if (cmd & OBD_BRW_WRITE) {
-                /* trigger a write rpc stream as long as there are dirtiers
-                 * waiting for space.  as they're waiting, they're not going to
-                 * create more pages to coalesce with what's waiting.. */
-                if (!cfs_list_empty(&cli->cl_cache_waiters)) {
-                        CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
-                        RETURN(1);
-                }
-                /* +16 to avoid triggering rpcs that would want to include pages
-                 * that are being queued but which can't be made ready until
-                 * the queuer finishes with the page. this is a wart for
-                 * llite::commit_write() */
-                optimal += 16;
+        if (aa->aa_ocapa) {
+                capa_put(aa->aa_ocapa);
+                aa->aa_ocapa = NULL;
         }
-        if (lop->lop_num_pending >= optimal)
-                RETURN(1);
 
-        RETURN(0);
+       cfs_list_for_each_entry_safe(ext, tmp, &aa->aa_exts, oe_link) {
+               if (obj == NULL && rc == 0) {
+                       obj = osc2cl(ext->oe_obj);
+                       cl_object_get(obj);
+               }
+
+               cfs_list_del_init(&ext->oe_link);
+               osc_extent_finish(env, ext, 1, rc);
+       }
+       LASSERT(cfs_list_empty(&aa->aa_exts));
+       LASSERT(cfs_list_empty(&aa->aa_oaps));
+
+       if (obj != NULL) {
+               struct obdo *oa = aa->aa_oa;
+               struct cl_attr *attr  = &osc_env_info(env)->oti_attr;
+               unsigned long valid = 0;
+
+               LASSERT(rc == 0);
+               if (oa->o_valid & OBD_MD_FLBLOCKS) {
+                       attr->cat_blocks = oa->o_blocks;
+                       valid |= CAT_BLOCKS;
+               }
+               if (oa->o_valid & OBD_MD_FLMTIME) {
+                       attr->cat_mtime = oa->o_mtime;
+                       valid |= CAT_MTIME;
+               }
+               if (oa->o_valid & OBD_MD_FLATIME) {
+                       attr->cat_atime = oa->o_atime;
+                       valid |= CAT_ATIME;
+               }
+               if (oa->o_valid & OBD_MD_FLCTIME) {
+                       attr->cat_ctime = oa->o_ctime;
+                       valid |= CAT_CTIME;
+               }
+               if (valid != 0) {
+                       cl_object_attr_lock(obj);
+                       cl_object_attr_set(env, obj, attr, valid);
+                       cl_object_attr_unlock(obj);
+               }
+               cl_object_put(env, obj);
+       }
+       OBDO_FREE(aa->aa_oa);
+
+       cl_req_completion(env, aa->aa_clerq, rc < 0 ? rc :
+                         req->rq_bulk->bd_nob_transferred);
+       osc_release_ppga(aa->aa_ppga, aa->aa_page_count);
+       ptlrpc_lprocfs_brw(req, req->rq_bulk->bd_nob_transferred);
+
+       client_obd_list_lock(&cli->cl_loi_list_lock);
+       /* We need to decrement before osc_ap_completion->osc_wake_cache_waiters
+        * is called so we know whether to go to sync BRWs or wait for more
+        * RPCs to complete */
+       if (lustre_msg_get_opc(req->rq_reqmsg) == OST_WRITE)
+               cli->cl_w_in_flight--;
+       else
+               cli->cl_r_in_flight--;
+       osc_wake_cache_waiters(cli);
+       client_obd_list_unlock(&cli->cl_loi_list_lock);
+
+       osc_io_unplug(env, cli, NULL, PDL_POLICY_SAME);
+       RETURN(rc);
+}
+
+static void brw_commit(struct ptlrpc_request *req)
+{
+       spin_lock(&req->rq_lock);
+       /* If osc_inc_unstable_pages (via osc_extent_finish) races with
+        * this called via the rq_commit_cb, I need to ensure
+        * osc_dec_unstable_pages is still called. Otherwise unstable
+        * pages may be leaked. */
+       if (req->rq_unstable)
+               osc_dec_unstable_pages(req);
+       else
+               req->rq_committed = 1;
+       spin_unlock(&req->rq_lock);
 }
 
-static int lop_makes_hprpc(struct loi_oap_pages *lop)
-{
+/**
+ * Build an RPC by the list of extent @ext_list. The caller must ensure
+ * that the total pages in this list are NOT over max pages per RPC.
+ * Extents in the list must be in OES_RPC state.
+ */
+int osc_build_rpc(const struct lu_env *env, struct client_obd *cli,
+                 cfs_list_t *ext_list, int cmd, pdl_policy_t pol)
+{
+       struct ptlrpc_request *req = NULL;
+       struct osc_extent *ext;
+       CFS_LIST_HEAD(rpc_list);
+       struct brw_page **pga = NULL;
+       struct osc_brw_async_args *aa = NULL;
+        struct obdo *oa = NULL;
         struct osc_async_page *oap;
-        ENTRY;
+        struct osc_async_page *tmp;
+        struct cl_req *clerq = NULL;
+        enum cl_req_type crt = (cmd & OBD_BRW_WRITE) ? CRT_WRITE : CRT_READ;
+        struct ldlm_lock *lock = NULL;
+        struct cl_req_attr crattr;
+       obd_off starting_offset = OBD_OBJECT_EOF;
+       obd_off ending_offset = 0;
+       int i, rc, mpflag = 0, mem_tight = 0, page_count = 0;
+
+       ENTRY;
+       LASSERT(!cfs_list_empty(ext_list));
+
+       /* add pages into rpc_list to build BRW rpc */
+       cfs_list_for_each_entry(ext, ext_list, oe_link) {
+               LASSERT(ext->oe_state == OES_RPC);
+               mem_tight |= ext->oe_memalloc;
+               cfs_list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
+                       ++page_count;
+                       cfs_list_add_tail(&oap->oap_rpc_item, &rpc_list);
+                       if (starting_offset > oap->oap_obj_off)
+                               starting_offset = oap->oap_obj_off;
+                       else
+                               LASSERT(oap->oap_page_off == 0);
+                       if (ending_offset < oap->oap_obj_off + oap->oap_count)
+                               ending_offset = oap->oap_obj_off +
+                                               oap->oap_count;
+                       else
+                               LASSERT(oap->oap_page_off + oap->oap_count ==
+                                       CFS_PAGE_SIZE);
+               }
+       }
+
+       if (mem_tight)
+               mpflag = cfs_memory_pressure_get_and_set();
+
+       memset(&crattr, 0, sizeof crattr);
+       OBD_ALLOC(pga, sizeof(*pga) * page_count);
+       if (pga == NULL)
+               GOTO(out, rc = -ENOMEM);
+
+       OBDO_ALLOC(oa);
+       if (oa == NULL)
+               GOTO(out, rc = -ENOMEM);
+
+       i = 0;
+       cfs_list_for_each_entry(oap, &rpc_list, oap_rpc_item) {
+               struct cl_page *page = oap2cl_page(oap);
+               if (clerq == NULL) {
+                       clerq = cl_req_alloc(env, page, crt,
+                                            1 /* only 1-object rpcs for
+                                               * now */);
+                       if (IS_ERR(clerq))
+                               GOTO(out, rc = PTR_ERR(clerq));
+                       lock = oap->oap_ldlm_lock;
+               }
+               if (mem_tight)
+                       oap->oap_brw_flags |= OBD_BRW_MEMALLOC;
+                pga[i] = &oap->oap_brw_page;
+                pga[i]->off = oap->oap_obj_off + oap->oap_page_off;
+                CDEBUG(0, "put page %p index %lu oap %p flg %x to pga\n",
+                       pga[i]->pg, cfs_page_index(oap->oap_page), oap, pga[i]->flag);
+                i++;
+                cl_req_page_add(env, clerq, page);
+        }
 
-        if (cfs_list_empty(&lop->lop_urgent))
-                RETURN(0);
+        /* always get the data for the obdo for the rpc */
+       LASSERT(clerq != NULL);
+       crattr.cra_oa = oa;
+       crattr.cra_capa = NULL;
+       memset(crattr.cra_jobid, 0, JOBSTATS_JOBID_SIZE);
+        cl_req_attr_set(env, clerq, &crattr, ~0ULL);
+        if (lock) {
+                oa->o_handle = lock->l_remote_handle;
+                oa->o_valid |= OBD_MD_FLHANDLE;
+        }
 
-        oap = cfs_list_entry(lop->lop_urgent.next,
-                         struct osc_async_page, oap_urgent_item);
+        rc = cl_req_prep(env, clerq);
+        if (rc != 0) {
+                CERROR("cl_req_prep failed: %d\n", rc);
+               GOTO(out, rc);
+       }
 
-        if (oap->oap_async_flags & ASYNC_HP) {
-                CDEBUG(D_CACHE, "hp request forcing RPC\n");
-                RETURN(1);
-        }
+       sort_brw_pages(pga, page_count);
+       rc = osc_brw_prep_request(cmd, cli, oa, NULL, page_count,
+                       pga, &req, crattr.cra_capa, 1, 0);
+       if (rc != 0) {
+               CERROR("prep_req failed: %d\n", rc);
+               GOTO(out, rc);
+       }
 
-        RETURN(0);
-}
+       req->rq_commit_cb = brw_commit;
+       req->rq_interpret_reply = brw_interpret;
 
-static void on_list(cfs_list_t *item, cfs_list_t *list,
-                    int should_be_on)
-{
-        if (cfs_list_empty(item) && should_be_on)
-                cfs_list_add_tail(item, list);
-        else if (!cfs_list_empty(item) && !should_be_on)
-                cfs_list_del_init(item);
-}
+       if (mem_tight != 0)
+                req->rq_memalloc = 1;
 
-/* maintain the loi's cli list membership invariants so that osc_send_oap_rpc
- * can find pages to build into rpcs quickly */
-void loi_list_maint(struct client_obd *cli, struct lov_oinfo *loi)
-{
-        if (lop_makes_hprpc(&loi->loi_write_lop) ||
-            lop_makes_hprpc(&loi->loi_read_lop)) {
-                /* HP rpc */
-                on_list(&loi->loi_ready_item, &cli->cl_loi_ready_list, 0);
-                on_list(&loi->loi_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
-        } else {
-                on_list(&loi->loi_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
-                on_list(&loi->loi_ready_item, &cli->cl_loi_ready_list,
-                        lop_makes_rpc(cli, &loi->loi_write_lop, OBD_BRW_WRITE)||
-                        lop_makes_rpc(cli, &loi->loi_read_lop, OBD_BRW_READ));
-        }
+        /* Need to update the timestamps after the request is built in case
+         * we race with setattr (locally or in queue at OST).  If OST gets
+         * later setattr before earlier BRW (as determined by the request xid),
+         * the OST will not use BRW timestamps.  Sadly, there is no obvious
+         * way to do this in a single call.  bug 10150 */
+        cl_req_attr_set(env, clerq, &crattr,
+                        OBD_MD_FLMTIME|OBD_MD_FLCTIME|OBD_MD_FLATIME);
 
-        on_list(&loi->loi_write_item, &cli->cl_loi_write_list,
-                loi->loi_write_lop.lop_num_pending);
+       lustre_msg_set_jobid(req->rq_reqmsg, crattr.cra_jobid);
+
+       CLASSERT(sizeof(*aa) <= sizeof(req->rq_async_args));
+       aa = ptlrpc_req_async_args(req);
+       CFS_INIT_LIST_HEAD(&aa->aa_oaps);
+       cfs_list_splice_init(&rpc_list, &aa->aa_oaps);
+       CFS_INIT_LIST_HEAD(&aa->aa_exts);
+       cfs_list_splice_init(ext_list, &aa->aa_exts);
+       aa->aa_clerq = clerq;
+
+       /* queued sync pages can be torn down while the pages
+        * were between the pending list and the rpc */
+       tmp = NULL;
+       cfs_list_for_each_entry(oap, &aa->aa_oaps, oap_rpc_item) {
+               /* only one oap gets a request reference */
+               if (tmp == NULL)
+                       tmp = oap;
+               if (oap->oap_interrupted && !req->rq_intr) {
+                       CDEBUG(D_INODE, "oap %p in req %p interrupted\n",
+                                       oap, req);
+                       ptlrpc_mark_interrupted(req);
+               }
+       }
+       if (tmp != NULL)
+               tmp->oap_request = ptlrpc_request_addref(req);
+
+       client_obd_list_lock(&cli->cl_loi_list_lock);
+       starting_offset >>= CFS_PAGE_SHIFT;
+       if (cmd == OBD_BRW_READ) {
+               cli->cl_r_in_flight++;
+               lprocfs_oh_tally_log2(&cli->cl_read_page_hist, page_count);
+               lprocfs_oh_tally(&cli->cl_read_rpc_hist, cli->cl_r_in_flight);
+               lprocfs_oh_tally_log2(&cli->cl_read_offset_hist,
+                                     starting_offset + 1);
+       } else {
+               cli->cl_w_in_flight++;
+               lprocfs_oh_tally_log2(&cli->cl_write_page_hist, page_count);
+               lprocfs_oh_tally(&cli->cl_write_rpc_hist, cli->cl_w_in_flight);
+               lprocfs_oh_tally_log2(&cli->cl_write_offset_hist,
+                                     starting_offset + 1);
+       }
+       client_obd_list_unlock(&cli->cl_loi_list_lock);
+
+       DEBUG_REQ(D_INODE, req, "%d pages, aa %p. now %dr/%dw in flight",
+                 page_count, aa, cli->cl_r_in_flight,
+                 cli->cl_w_in_flight);
+
+       /* XXX: Maybe the caller can check the RPC bulk descriptor to
+        * see which CPU/NUMA node the majority of pages were allocated
+        * on, and try to assign the async RPC to the CPU core
+        * (PDL_POLICY_PREFERRED) to reduce cross-CPU memory traffic.
+        *
+        * But on the other hand, we expect that multiple ptlrpcd
+        * threads and the initial write sponsor can run in parallel,
+        * especially when data checksum is enabled, which is CPU-bound
+        * operation and single ptlrpcd thread cannot process in time.
+        * So more ptlrpcd threads sharing BRW load
+        * (with PDL_POLICY_ROUND) seems better.
+        */
+       ptlrpcd_add_req(req, pol, -1);
+       rc = 0;
+       EXIT;
 
-        on_list(&loi->loi_read_item, &cli->cl_loi_read_list,
-                loi->loi_read_lop.lop_num_pending);
-}
+out:
+       if (mem_tight != 0)
+               cfs_memory_pressure_restore(mpflag);
 
-static void lop_update_pending(struct client_obd *cli,
-                               struct loi_oap_pages *lop, int cmd, int delta)
-{
-        lop->lop_num_pending += delta;
-        if (cmd & OBD_BRW_WRITE)
-                cli->cl_pending_w_pages += delta;
-        else
-                cli->cl_pending_r_pages += delta;
+       capa_put(crattr.cra_capa);
+       if (rc != 0) {
+               LASSERT(req == NULL);
+
+                if (oa)
+                        OBDO_FREE(oa);
+                if (pga)
+                        OBD_FREE(pga, sizeof(*pga) * page_count);
+                /* this should happen rarely and is pretty bad, it makes the
+                 * pending list not follow the dirty order */
+               while (!cfs_list_empty(ext_list)) {
+                       ext = cfs_list_entry(ext_list->next, struct osc_extent,
+                                            oe_link);
+                       cfs_list_del_init(&ext->oe_link);
+                       osc_extent_finish(env, ext, 0, rc);
+               }
+               if (clerq && !IS_ERR(clerq))
+                       cl_req_completion(env, clerq, rc);
+       }
+       RETURN(rc);
 }
 
-/**
- * this is called when a sync waiter receives an interruption.  Its job is to
- * get the caller woken as soon as possible.  If its page hasn't been put in an
- * rpc yet it can dequeue immediately.  Otherwise it has to mark the rpc as
- * desiring interruption which will forcefully complete the rpc once the rpc
- * has timed out.
- */
-int osc_oap_interrupted(const struct lu_env *env, struct osc_async_page *oap)
+static int osc_set_lock_data_with_check(struct ldlm_lock *lock,
+                                        struct ldlm_enqueue_info *einfo)
 {
-        struct loi_oap_pages *lop;
-        struct lov_oinfo *loi;
-        int rc = -EBUSY;
-        ENTRY;
+        void *data = einfo->ei_cbdata;
+        int set = 0;
 
-        LASSERT(!oap->oap_interrupted);
-        oap->oap_interrupted = 1;
+        LASSERT(lock != NULL);
+        LASSERT(lock->l_blocking_ast == einfo->ei_cb_bl);
+        LASSERT(lock->l_resource->lr_type == einfo->ei_type);
+        LASSERT(lock->l_completion_ast == einfo->ei_cb_cp);
+        LASSERT(lock->l_glimpse_ast == einfo->ei_cb_gl);
 
-        /* ok, it's been put in an rpc. only one oap gets a request reference */
-        if (oap->oap_request != NULL) {
-                ptlrpc_mark_interrupted(oap->oap_request);
-                ptlrpcd_wake(oap->oap_request);
-                ptlrpc_req_finished(oap->oap_request);
-                oap->oap_request = NULL;
-        }
-
-        /*
-         * page completion may be called only if ->cpo_prep() method was
-         * executed by osc_io_submit(), that also adds page the to pending list
-         */
-        if (!cfs_list_empty(&oap->oap_pending_item)) {
-                cfs_list_del_init(&oap->oap_pending_item);
-                cfs_list_del_init(&oap->oap_urgent_item);
-
-                loi = oap->oap_loi;
-                lop = (oap->oap_cmd & OBD_BRW_WRITE) ?
-                        &loi->loi_write_lop : &loi->loi_read_lop;
-                lop_update_pending(oap->oap_cli, lop, oap->oap_cmd, -1);
-                loi_list_maint(oap->oap_cli, oap->oap_loi);
-                rc = oap->oap_caller_ops->ap_completion(env,
-                                          oap->oap_caller_data,
-                                          oap->oap_cmd, NULL, -EINTR);
-        }
-
-        RETURN(rc);
-}
-
-/* this is trying to propogate async writeback errors back up to the
- * application.  As an async write fails we record the error code for later if
- * the app does an fsync.  As long as errors persist we force future rpcs to be
- * sync so that the app can get a sync error and break the cycle of queueing
- * pages for which writeback will fail. */
-static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
-                           int rc)
-{
-        if (rc) {
-                if (!ar->ar_rc)
-                        ar->ar_rc = rc;
-
-                ar->ar_force_sync = 1;
-                ar->ar_min_xid = ptlrpc_sample_next_xid();
-                return;
-
-        }
-
-        if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
-                ar->ar_force_sync = 0;
-}
-
-void osc_oap_to_pending(struct osc_async_page *oap)
-{
-        struct loi_oap_pages *lop;
-
-        if (oap->oap_cmd & OBD_BRW_WRITE)
-                lop = &oap->oap_loi->loi_write_lop;
-        else
-                lop = &oap->oap_loi->loi_read_lop;
-
-        if (oap->oap_async_flags & ASYNC_HP)
-                cfs_list_add(&oap->oap_urgent_item, &lop->lop_urgent);
-        else if (oap->oap_async_flags & ASYNC_URGENT)
-                cfs_list_add_tail(&oap->oap_urgent_item, &lop->lop_urgent);
-        cfs_list_add_tail(&oap->oap_pending_item, &lop->lop_pending);
-        lop_update_pending(oap->oap_cli, lop, oap->oap_cmd, 1);
-}
-
-/* this must be called holding the loi list lock to give coverage to exit_cache,
- * async_flag maintenance, and oap_request */
-static void osc_ap_completion(const struct lu_env *env,
-                              struct client_obd *cli, struct obdo *oa,
-                              struct osc_async_page *oap, int sent, int rc)
-{
-        __u64 xid = 0;
-
-        ENTRY;
-        if (oap->oap_request != NULL) {
-                xid = ptlrpc_req_xid(oap->oap_request);
-                ptlrpc_req_finished(oap->oap_request);
-                oap->oap_request = NULL;
-        }
-
-        cfs_spin_lock(&oap->oap_lock);
-        oap->oap_async_flags = 0;
-        cfs_spin_unlock(&oap->oap_lock);
-        oap->oap_interrupted = 0;
-
-        if (oap->oap_cmd & OBD_BRW_WRITE) {
-                osc_process_ar(&cli->cl_ar, xid, rc);
-                osc_process_ar(&oap->oap_loi->loi_ar, xid, rc);
-        }
-
-        if (rc == 0 && oa != NULL) {
-                if (oa->o_valid & OBD_MD_FLBLOCKS)
-                        oap->oap_loi->loi_lvb.lvb_blocks = oa->o_blocks;
-                if (oa->o_valid & OBD_MD_FLMTIME)
-                        oap->oap_loi->loi_lvb.lvb_mtime = oa->o_mtime;
-                if (oa->o_valid & OBD_MD_FLATIME)
-                        oap->oap_loi->loi_lvb.lvb_atime = oa->o_atime;
-                if (oa->o_valid & OBD_MD_FLCTIME)
-                        oap->oap_loi->loi_lvb.lvb_ctime = oa->o_ctime;
-        }
-
-        rc = oap->oap_caller_ops->ap_completion(env, oap->oap_caller_data,
-                                                oap->oap_cmd, oa, rc);
-
-        /* ll_ap_completion (from llite) drops PG_locked. so, a new
-         * I/O on the page could start, but OSC calls it under lock
-         * and thus we can add oap back to pending safely */
-        if (rc)
-                /* upper layer wants to leave the page on pending queue */
-                osc_oap_to_pending(oap);
-        else
-                osc_exit_cache(cli, oap, sent);
-        EXIT;
-}
-
-static int brw_interpret(const struct lu_env *env,
-                         struct ptlrpc_request *req, void *data, int rc)
-{
-        struct osc_brw_async_args *aa = data;
-        struct client_obd *cli;
-        int async;
-        ENTRY;
-
-        rc = osc_brw_fini_request(req, rc);
-        CDEBUG(D_INODE, "request %p aa %p rc %d\n", req, aa, rc);
-        if (osc_recoverable_error(rc)) {
-                /* Only retry once for mmaped files since the mmaped page
-                 * might be modified at anytime. We have to retry at least
-                 * once in case there WAS really a corruption of the page
-                 * on the network, that was not caused by mmap() modifying
-                 * the page. Bug11742 */
-                if ((rc == -EAGAIN) && (aa->aa_resends > 0) &&
-                    aa->aa_oa->o_valid & OBD_MD_FLFLAGS &&
-                    aa->aa_oa->o_flags & OBD_FL_MMAP) {
-                        rc = 0;
-                } else {
-                        rc = osc_brw_redo_request(req, aa);
-                        if (rc == 0)
-                                RETURN(0);
-                }
-        }
-
-        if (aa->aa_ocapa) {
-                capa_put(aa->aa_ocapa);
-                aa->aa_ocapa = NULL;
-        }
-
-        cli = aa->aa_cli;
-
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-
-        /* We need to decrement before osc_ap_completion->osc_wake_cache_waiters
-         * is called so we know whether to go to sync BRWs or wait for more
-         * RPCs to complete */
-        if (lustre_msg_get_opc(req->rq_reqmsg) == OST_WRITE)
-                cli->cl_w_in_flight--;
-        else
-                cli->cl_r_in_flight--;
-
-        async = cfs_list_empty(&aa->aa_oaps);
-        if (!async) { /* from osc_send_oap_rpc() */
-                struct osc_async_page *oap, *tmp;
-                /* the caller may re-use the oap after the completion call so
-                 * we need to clean it up a little */
-                cfs_list_for_each_entry_safe(oap, tmp, &aa->aa_oaps,
-                                             oap_rpc_item) {
-                        cfs_list_del_init(&oap->oap_rpc_item);
-                        osc_ap_completion(env, cli, aa->aa_oa, oap, 1, rc);
-                }
-                OBDO_FREE(aa->aa_oa);
-        } else { /* from async_internal() */
-                obd_count i;
-                for (i = 0; i < aa->aa_page_count; i++)
-                        osc_release_write_grant(aa->aa_cli, aa->aa_ppga[i], 1);
-        }
-        osc_wake_cache_waiters(cli);
-        osc_check_rpcs(env, cli);
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
-        if (!async)
-                cl_req_completion(env, aa->aa_clerq, rc);
-        osc_release_ppga(aa->aa_ppga, aa->aa_page_count);
-
-        RETURN(rc);
-}
-
-static struct ptlrpc_request *osc_build_req(const struct lu_env *env,
-                                            struct client_obd *cli,
-                                            cfs_list_t *rpc_list,
-                                            int page_count, int cmd)
-{
-        struct ptlrpc_request *req;
-        struct brw_page **pga = NULL;
-        struct osc_brw_async_args *aa;
-        struct obdo *oa = NULL;
-        const struct obd_async_page_ops *ops = NULL;
-        void *caller_data = NULL;
-        struct osc_async_page *oap;
-        struct osc_async_page *tmp;
-        struct ost_body *body;
-        struct cl_req *clerq = NULL;
-        enum cl_req_type crt = (cmd & OBD_BRW_WRITE) ? CRT_WRITE : CRT_READ;
-        struct ldlm_lock *lock = NULL;
-        struct cl_req_attr crattr;
-        int i, rc, mpflag = 0;
-
-        ENTRY;
-        LASSERT(!cfs_list_empty(rpc_list));
-
-        if (cmd & OBD_BRW_MEMALLOC)
-                mpflag = cfs_memory_pressure_get_and_set();
-
-        memset(&crattr, 0, sizeof crattr);
-        OBD_ALLOC(pga, sizeof(*pga) * page_count);
-        if (pga == NULL)
-                GOTO(out, req = ERR_PTR(-ENOMEM));
-
-        OBDO_ALLOC(oa);
-        if (oa == NULL)
-                GOTO(out, req = ERR_PTR(-ENOMEM));
-
-        i = 0;
-        cfs_list_for_each_entry(oap, rpc_list, oap_rpc_item) {
-                struct cl_page *page = osc_oap2cl_page(oap);
-                if (ops == NULL) {
-                        ops = oap->oap_caller_ops;
-                        caller_data = oap->oap_caller_data;
-
-                        clerq = cl_req_alloc(env, page, crt,
-                                             1 /* only 1-object rpcs for
-                                                * now */);
-                        if (IS_ERR(clerq))
-                                GOTO(out, req = (void *)clerq);
-                        lock = oap->oap_ldlm_lock;
-                }
-                pga[i] = &oap->oap_brw_page;
-                pga[i]->off = oap->oap_obj_off + oap->oap_page_off;
-                CDEBUG(0, "put page %p index %lu oap %p flg %x to pga\n",
-                       pga[i]->pg, cfs_page_index(oap->oap_page), oap, pga[i]->flag);
-                i++;
-                cl_req_page_add(env, clerq, page);
-        }
-
-        /* always get the data for the obdo for the rpc */
-        LASSERT(ops != NULL);
-        crattr.cra_oa = oa;
-        crattr.cra_capa = NULL;
-        cl_req_attr_set(env, clerq, &crattr, ~0ULL);
-        if (lock) {
-                oa->o_handle = lock->l_remote_handle;
-                oa->o_valid |= OBD_MD_FLHANDLE;
-        }
-
-        rc = cl_req_prep(env, clerq);
-        if (rc != 0) {
-                CERROR("cl_req_prep failed: %d\n", rc);
-                GOTO(out, req = ERR_PTR(rc));
-        }
-
-        sort_brw_pages(pga, page_count);
-        rc = osc_brw_prep_request(cmd, cli, oa, NULL, page_count,
-                                  pga, &req, crattr.cra_capa, 1);
-        if (rc != 0) {
-                CERROR("prep_req failed: %d\n", rc);
-                GOTO(out, req = ERR_PTR(rc));
-        }
-
-        if (cmd & OBD_BRW_MEMALLOC)
-                req->rq_memalloc = 1;
-
-        /* Need to update the timestamps after the request is built in case
-         * we race with setattr (locally or in queue at OST).  If OST gets
-         * later setattr before earlier BRW (as determined by the request xid),
-         * the OST will not use BRW timestamps.  Sadly, there is no obvious
-         * way to do this in a single call.  bug 10150 */
-        body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
-        cl_req_attr_set(env, clerq, &crattr,
-                        OBD_MD_FLMTIME|OBD_MD_FLCTIME|OBD_MD_FLATIME);
-
-        CLASSERT(sizeof(*aa) <= sizeof(req->rq_async_args));
-        aa = ptlrpc_req_async_args(req);
-        CFS_INIT_LIST_HEAD(&aa->aa_oaps);
-        cfs_list_splice(rpc_list, &aa->aa_oaps);
-        CFS_INIT_LIST_HEAD(rpc_list);
-        aa->aa_clerq = clerq;
-out:
-        if (cmd & OBD_BRW_MEMALLOC)
-                cfs_memory_pressure_restore(mpflag);
-
-        capa_put(crattr.cra_capa);
-        if (IS_ERR(req)) {
-                if (oa)
-                        OBDO_FREE(oa);
-                if (pga)
-                        OBD_FREE(pga, sizeof(*pga) * page_count);
-                /* this should happen rarely and is pretty bad, it makes the
-                 * pending list not follow the dirty order */
-                client_obd_list_lock(&cli->cl_loi_list_lock);
-                cfs_list_for_each_entry_safe(oap, tmp, rpc_list, oap_rpc_item) {
-                        cfs_list_del_init(&oap->oap_rpc_item);
-
-                        /* queued sync pages can be torn down while the pages
-                         * were between the pending list and the rpc */
-                        if (oap->oap_interrupted) {
-                                CDEBUG(D_INODE, "oap %p interrupted\n", oap);
-                                osc_ap_completion(env, cli, NULL, oap, 0,
-                                                  oap->oap_count);
-                                continue;
-                        }
-                        osc_ap_completion(env, cli, NULL, oap, 0, PTR_ERR(req));
-                }
-                if (clerq && !IS_ERR(clerq))
-                        cl_req_completion(env, clerq, PTR_ERR(req));
-        }
-        RETURN(req);
-}
-
-/**
- * prepare pages for ASYNC io and put pages in send queue.
- *
- * \param cmd OBD_BRW_* macroses
- * \param lop pending pages
- *
- * \return zero if no page added to send queue.
- * \return 1 if pages successfully added to send queue.
- * \return negative on errors.
- */
-static int
-osc_send_oap_rpc(const struct lu_env *env, struct client_obd *cli,
-                 struct lov_oinfo *loi,
-                 int cmd, struct loi_oap_pages *lop)
-{
-        struct ptlrpc_request *req;
-        obd_count page_count = 0;
-        struct osc_async_page *oap = NULL, *tmp;
-        struct osc_brw_async_args *aa;
-        const struct obd_async_page_ops *ops;
-        CFS_LIST_HEAD(rpc_list);
-        CFS_LIST_HEAD(tmp_list);
-        unsigned int ending_offset;
-        unsigned  starting_offset = 0;
-        int srvlock = 0, mem_tight = 0;
-        struct cl_object *clob = NULL;
-        ENTRY;
-
-        /* ASYNC_HP pages first. At present, when the lock the pages is
-         * to be canceled, the pages covered by the lock will be sent out
-         * with ASYNC_HP. We have to send out them as soon as possible. */
-        cfs_list_for_each_entry_safe(oap, tmp, &lop->lop_urgent, oap_urgent_item) {
-                if (oap->oap_async_flags & ASYNC_HP) 
-                        cfs_list_move(&oap->oap_pending_item, &tmp_list);
-                else
-                        cfs_list_move_tail(&oap->oap_pending_item, &tmp_list);
-                if (++page_count >= cli->cl_max_pages_per_rpc)
-                        break;
-        }
-
-        cfs_list_splice(&tmp_list, &lop->lop_pending);
-        page_count = 0;
-
-        /* first we find the pages we're allowed to work with */
-        cfs_list_for_each_entry_safe(oap, tmp, &lop->lop_pending,
-                                     oap_pending_item) {
-                ops = oap->oap_caller_ops;
-
-                LASSERTF(oap->oap_magic == OAP_MAGIC, "Bad oap magic: oap %p, "
-                         "magic 0x%x\n", oap, oap->oap_magic);
-
-                if (clob == NULL) {
-                        /* pin object in memory, so that completion call-backs
-                         * can be safely called under client_obd_list lock. */
-                        clob = osc_oap2cl_page(oap)->cp_obj;
-                        cl_object_get(clob);
-                }
-
-                if (page_count != 0 &&
-                    srvlock != !!(oap->oap_brw_flags & OBD_BRW_SRVLOCK)) {
-                        CDEBUG(D_PAGE, "SRVLOCK flag mismatch,"
-                               " oap %p, page %p, srvlock %u\n",
-                               oap, oap->oap_brw_page.pg, (unsigned)!srvlock);
-                        break;
-                }
-
-                /* If there is a gap at the start of this page, it can't merge
-                 * with any previous page, so we'll hand the network a
-                 * "fragmented" page array that it can't transfer in 1 RDMA */
-                if (page_count != 0 && oap->oap_page_off != 0)
-                        break;
-
-                /* in llite being 'ready' equates to the page being locked
-                 * until completion unlocks it.  commit_write submits a page
-                 * as not ready because its unlock will happen unconditionally
-                 * as the call returns.  if we race with commit_write giving
-                 * us that page we don't want to create a hole in the page
-                 * stream, so we stop and leave the rpc to be fired by
-                 * another dirtier or kupdated interval (the not ready page
-                 * will still be on the dirty list).  we could call in
-                 * at the end of ll_file_write to process the queue again. */
-                if (!(oap->oap_async_flags & ASYNC_READY)) {
-                        int rc = ops->ap_make_ready(env, oap->oap_caller_data,
-                                                    cmd);
-                        if (rc < 0)
-                                CDEBUG(D_INODE, "oap %p page %p returned %d "
-                                                "instead of ready\n", oap,
-                                                oap->oap_page, rc);
-                        switch (rc) {
-                        case -EAGAIN:
-                                /* llite is telling us that the page is still
-                                 * in commit_write and that we should try
-                                 * and put it in an rpc again later.  we
-                                 * break out of the loop so we don't create
-                                 * a hole in the sequence of pages in the rpc
-                                 * stream.*/
-                                oap = NULL;
-                                break;
-                        case -EINTR:
-                                /* the io isn't needed.. tell the checks
-                                 * below to complete the rpc with EINTR */
-                                cfs_spin_lock(&oap->oap_lock);
-                                oap->oap_async_flags |= ASYNC_COUNT_STABLE;
-                                cfs_spin_unlock(&oap->oap_lock);
-                                oap->oap_count = -EINTR;
-                                break;
-                        case 0:
-                                cfs_spin_lock(&oap->oap_lock);
-                                oap->oap_async_flags |= ASYNC_READY;
-                                cfs_spin_unlock(&oap->oap_lock);
-                                break;
-                        default:
-                                LASSERTF(0, "oap %p page %p returned %d "
-                                            "from make_ready\n", oap,
-                                            oap->oap_page, rc);
-                                break;
-                        }
-                }
-                if (oap == NULL)
-                        break;
-                /*
-                 * Page submitted for IO has to be locked. Either by
-                 * ->ap_make_ready() or by higher layers.
-                 */
-#if defined(__KERNEL__) && defined(__linux__)
-                {
-                        struct cl_page *page;
-
-                        page = osc_oap2cl_page(oap);
-
-                        if (page->cp_type == CPT_CACHEABLE &&
-                            !(PageLocked(oap->oap_page) &&
-                              (CheckWriteback(oap->oap_page, cmd)))) {
-                                CDEBUG(D_PAGE, "page %p lost wb %lx/%x\n",
-                                       oap->oap_page,
-                                       (long)oap->oap_page->flags,
-                                       oap->oap_async_flags);
-                                LBUG();
-                        }
-                }
-#endif
-
-                /* take the page out of our book-keeping */
-                cfs_list_del_init(&oap->oap_pending_item);
-                lop_update_pending(cli, lop, cmd, -1);
-                cfs_list_del_init(&oap->oap_urgent_item);
-
-                if (page_count == 0)
-                        starting_offset = (oap->oap_obj_off+oap->oap_page_off) &
-                                          (PTLRPC_MAX_BRW_SIZE - 1);
-
-                /* ask the caller for the size of the io as the rpc leaves. */
-                if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
-                        oap->oap_count =
-                                ops->ap_refresh_count(env, oap->oap_caller_data,
-                                                      cmd);
-                        LASSERT(oap->oap_page_off + oap->oap_count <= CFS_PAGE_SIZE);
-                }
-                if (oap->oap_count <= 0) {
-                        CDEBUG(D_CACHE, "oap %p count %d, completing\n", oap,
-                               oap->oap_count);
-                        osc_ap_completion(env, cli, NULL,
-                                          oap, 0, oap->oap_count);
-                        continue;
-                }
-
-                /* now put the page back in our accounting */
-                cfs_list_add_tail(&oap->oap_rpc_item, &rpc_list);
-                if (oap->oap_brw_flags & OBD_BRW_MEMALLOC)
-                        mem_tight = 1;
-                if (page_count == 0)
-                        srvlock = !!(oap->oap_brw_flags & OBD_BRW_SRVLOCK);
-                if (++page_count >= cli->cl_max_pages_per_rpc)
-                        break;
-
-                /* End on a PTLRPC_MAX_BRW_SIZE boundary.  We want full-sized
-                 * RPCs aligned on PTLRPC_MAX_BRW_SIZE boundaries to help reads
-                 * have the same alignment as the initial writes that allocated
-                 * extents on the server. */
-                ending_offset = (oap->oap_obj_off + oap->oap_page_off +
-                                 oap->oap_count) & (PTLRPC_MAX_BRW_SIZE - 1);
-                if (ending_offset == 0)
-                        break;
-
-                /* If there is a gap at the end of this page, it can't merge
-                 * with any subsequent pages, so we'll hand the network a
-                 * "fragmented" page array that it can't transfer in 1 RDMA */
-                if (oap->oap_page_off + oap->oap_count < CFS_PAGE_SIZE)
-                        break;
-        }
-
-        osc_wake_cache_waiters(cli);
-
-        loi_list_maint(cli, loi);
-
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
-
-        if (clob != NULL)
-                cl_object_put(env, clob);
-
-        if (page_count == 0) {
-                client_obd_list_lock(&cli->cl_loi_list_lock);
-                RETURN(0);
-        }
-
-        req = osc_build_req(env, cli, &rpc_list, page_count,
-                            mem_tight ? (cmd | OBD_BRW_MEMALLOC) : cmd);
-        if (IS_ERR(req)) {
-                LASSERT(cfs_list_empty(&rpc_list));
-                loi_list_maint(cli, loi);
-                RETURN(PTR_ERR(req));
-        }
-
-        aa = ptlrpc_req_async_args(req);
-
-        if (cmd == OBD_BRW_READ) {
-                lprocfs_oh_tally_log2(&cli->cl_read_page_hist, page_count);
-                lprocfs_oh_tally(&cli->cl_read_rpc_hist, cli->cl_r_in_flight);
-                lprocfs_oh_tally_log2(&cli->cl_read_offset_hist,
-                                      (starting_offset >> CFS_PAGE_SHIFT) + 1);
-        } else {
-                lprocfs_oh_tally_log2(&cli->cl_write_page_hist, page_count);
-                lprocfs_oh_tally(&cli->cl_write_rpc_hist,
-                                 cli->cl_w_in_flight);
-                lprocfs_oh_tally_log2(&cli->cl_write_offset_hist,
-                                      (starting_offset >> CFS_PAGE_SHIFT) + 1);
-        }
-        ptlrpc_lprocfs_brw(req, aa->aa_requested_nob);
-
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-
-        if (cmd == OBD_BRW_READ)
-                cli->cl_r_in_flight++;
-        else
-                cli->cl_w_in_flight++;
-
-        /* queued sync pages can be torn down while the pages
-         * were between the pending list and the rpc */
-        tmp = NULL;
-        cfs_list_for_each_entry(oap, &aa->aa_oaps, oap_rpc_item) {
-                /* only one oap gets a request reference */
-                if (tmp == NULL)
-                        tmp = oap;
-                if (oap->oap_interrupted && !req->rq_intr) {
-                        CDEBUG(D_INODE, "oap %p in req %p interrupted\n",
-                               oap, req);
-                        ptlrpc_mark_interrupted(req);
-                }
-        }
-        if (tmp != NULL)
-                tmp->oap_request = ptlrpc_request_addref(req);
-
-        DEBUG_REQ(D_INODE, req, "%d pages, aa %p. now %dr/%dw in flight",
-                  page_count, aa, cli->cl_r_in_flight, cli->cl_w_in_flight);
-
-        req->rq_interpret_reply = brw_interpret;
-        ptlrpcd_add_req(req, PSCOPE_BRW);
-        RETURN(1);
-}
-
-#define LOI_DEBUG(LOI, STR, args...)                                     \
-        CDEBUG(D_INODE, "loi ready %d wr %d:%d rd %d:%d " STR,           \
-               !cfs_list_empty(&(LOI)->loi_ready_item) ||                \
-               !cfs_list_empty(&(LOI)->loi_hp_ready_item),               \
-               (LOI)->loi_write_lop.lop_num_pending,                     \
-               !cfs_list_empty(&(LOI)->loi_write_lop.lop_urgent),        \
-               (LOI)->loi_read_lop.lop_num_pending,                      \
-               !cfs_list_empty(&(LOI)->loi_read_lop.lop_urgent),         \
-               args)                                                     \
-
-/* This is called by osc_check_rpcs() to find which objects have pages that
- * we could be sending.  These lists are maintained by lop_makes_rpc(). */
-struct lov_oinfo *osc_next_loi(struct client_obd *cli)
-{
-        ENTRY;
-
-        /* First return objects that have blocked locks so that they
-         * will be flushed quickly and other clients can get the lock,
-         * then objects which have pages ready to be stuffed into RPCs */
-        if (!cfs_list_empty(&cli->cl_loi_hp_ready_list))
-                RETURN(cfs_list_entry(cli->cl_loi_hp_ready_list.next,
-                                      struct lov_oinfo, loi_hp_ready_item));
-        if (!cfs_list_empty(&cli->cl_loi_ready_list))
-                RETURN(cfs_list_entry(cli->cl_loi_ready_list.next,
-                                      struct lov_oinfo, loi_ready_item));
-
-        /* then if we have cache waiters, return all objects with queued
-         * writes.  This is especially important when many small files
-         * have filled up the cache and not been fired into rpcs because
-         * they don't pass the nr_pending/object threshhold */
-        if (!cfs_list_empty(&cli->cl_cache_waiters) &&
-            !cfs_list_empty(&cli->cl_loi_write_list))
-                RETURN(cfs_list_entry(cli->cl_loi_write_list.next,
-                                      struct lov_oinfo, loi_write_item));
-
-        /* then return all queued objects when we have an invalid import
-         * so that they get flushed */
-        if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
-                if (!cfs_list_empty(&cli->cl_loi_write_list))
-                        RETURN(cfs_list_entry(cli->cl_loi_write_list.next,
-                                              struct lov_oinfo,
-                                              loi_write_item));
-                if (!cfs_list_empty(&cli->cl_loi_read_list))
-                        RETURN(cfs_list_entry(cli->cl_loi_read_list.next,
-                                              struct lov_oinfo, loi_read_item));
-        }
-        RETURN(NULL);
-}
-
-static int osc_max_rpc_in_flight(struct client_obd *cli, struct lov_oinfo *loi)
-{
-        struct osc_async_page *oap;
-        int hprpc = 0;
-
-        if (!cfs_list_empty(&loi->loi_write_lop.lop_urgent)) {
-                oap = cfs_list_entry(loi->loi_write_lop.lop_urgent.next,
-                                     struct osc_async_page, oap_urgent_item);
-                hprpc = !!(oap->oap_async_flags & ASYNC_HP);
-        }
-
-        if (!hprpc && !cfs_list_empty(&loi->loi_read_lop.lop_urgent)) {
-                oap = cfs_list_entry(loi->loi_read_lop.lop_urgent.next,
-                                     struct osc_async_page, oap_urgent_item);
-                hprpc = !!(oap->oap_async_flags & ASYNC_HP);
-        }
-
-        return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
-}
-
-/* called with the loi list lock held */
-void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli)
-{
-        struct lov_oinfo *loi;
-        int rc = 0, race_counter = 0;
-        ENTRY;
-
-        while ((loi = osc_next_loi(cli)) != NULL) {
-                LOI_DEBUG(loi, "%lu in flight\n", rpcs_in_flight(cli));
-
-                if (osc_max_rpc_in_flight(cli, loi))
-                        break;
-
-                /* attempt some read/write balancing by alternating between
-                 * reads and writes in an object.  The makes_rpc checks here
-                 * would be redundant if we were getting read/write work items
-                 * instead of objects.  we don't want send_oap_rpc to drain a
-                 * partial read pending queue when we're given this object to
-                 * do io on writes while there are cache waiters */
-                if (lop_makes_rpc(cli, &loi->loi_write_lop, OBD_BRW_WRITE)) {
-                        rc = osc_send_oap_rpc(env, cli, loi, OBD_BRW_WRITE,
-                                              &loi->loi_write_lop);
-                        if (rc < 0) {
-                                CERROR("Write request failed with %d\n", rc);
-
-                                /* osc_send_oap_rpc failed, mostly because of
-                                 * memory pressure.
-                                 *
-                                 * It can't break here, because if:
-                                 *  - a page was submitted by osc_io_submit, so
-                                 *    page locked;
-                                 *  - no request in flight
-                                 *  - no subsequent request
-                                 * The system will be in live-lock state,
-                                 * because there is no chance to call
-                                 * osc_io_unplug() and osc_check_rpcs() any
-                                 * more. pdflush can't help in this case,
-                                 * because it might be blocked at grabbing
-                                 * the page lock as we mentioned.
-                                 *
-                                 * Anyway, continue to drain pages. */
-                                /* break; */
-                        }
-
-                        if (rc > 0)
-                                race_counter = 0;
-                        else
-                                race_counter++;
-                }
-                if (lop_makes_rpc(cli, &loi->loi_read_lop, OBD_BRW_READ)) {
-                        rc = osc_send_oap_rpc(env, cli, loi, OBD_BRW_READ,
-                                              &loi->loi_read_lop);
-                        if (rc < 0)
-                                CERROR("Read request failed with %d\n", rc);
-
-                        if (rc > 0)
-                                race_counter = 0;
-                        else
-                                race_counter++;
-                }
-
-                /* attempt some inter-object balancing by issuing rpcs
-                 * for each object in turn */
-                if (!cfs_list_empty(&loi->loi_hp_ready_item))
-                        cfs_list_del_init(&loi->loi_hp_ready_item);
-                if (!cfs_list_empty(&loi->loi_ready_item))
-                        cfs_list_del_init(&loi->loi_ready_item);
-                if (!cfs_list_empty(&loi->loi_write_item))
-                        cfs_list_del_init(&loi->loi_write_item);
-                if (!cfs_list_empty(&loi->loi_read_item))
-                        cfs_list_del_init(&loi->loi_read_item);
-
-                loi_list_maint(cli, loi);
-
-                /* send_oap_rpc fails with 0 when make_ready tells it to
-                 * back off.  llite's make_ready does this when it tries
-                 * to lock a page queued for write that is already locked.
-                 * we want to try sending rpcs from many objects, but we
-                 * don't want to spin failing with 0.  */
-                if (race_counter == 10)
-                        break;
-        }
-        EXIT;
-}
-
-/* we're trying to queue a page in the osc so we're subject to the
- * 'cl_dirty_max' limit on the number of pages that can be queued in the osc.
- * If the osc's queued pages are already at that limit, then we want to sleep
- * until there is space in the osc's queue for us.  We also may be waiting for
- * write credits from the OST if there are RPCs in flight that may return some
- * before we fall back to sync writes.
- *
- * We need this know our allocation was granted in the presence of signals */
-static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
-{
-        int rc;
-        ENTRY;
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-        rc = cfs_list_empty(&ocw->ocw_entry) || rpcs_in_flight(cli) == 0;
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
-        RETURN(rc);
-};
-
-/**
- * Non-blocking version of osc_enter_cache() that consumes grant only when it
- * is available.
- */
-int osc_enter_cache_try(const struct lu_env *env,
-                        struct client_obd *cli, struct lov_oinfo *loi,
-                        struct osc_async_page *oap, int transient)
-{
-        int has_grant;
-
-        has_grant = cli->cl_avail_grant >= CFS_PAGE_SIZE;
-        if (has_grant) {
-                osc_consume_write_grant(cli, &oap->oap_brw_page);
-                if (transient) {
-                        cli->cl_dirty_transit += CFS_PAGE_SIZE;
-                        cfs_atomic_inc(&obd_dirty_transit_pages);
-                        oap->oap_brw_flags |= OBD_BRW_NOCACHE;
-                }
-        }
-        return has_grant;
-}
-
-/* Caller must hold loi_list_lock - we drop/regain it if we need to wait for
- * grant or cache space. */
-static int osc_enter_cache(const struct lu_env *env,
-                           struct client_obd *cli, struct lov_oinfo *loi,
-                           struct osc_async_page *oap)
-{
-        struct osc_cache_waiter ocw;
-        struct l_wait_info lwi = { 0 };
-
-        ENTRY;
-
-        CDEBUG(D_CACHE, "dirty: %ld/%d dirty_max: %ld/%d dropped: %lu "
-               "grant: %lu\n", cli->cl_dirty, cfs_atomic_read(&obd_dirty_pages),
-               cli->cl_dirty_max, obd_max_dirty_pages,
-               cli->cl_lost_grant, cli->cl_avail_grant);
-
-        /* force the caller to try sync io.  this can jump the list
-         * of queued writes and create a discontiguous rpc stream */
-        if (cli->cl_dirty_max < CFS_PAGE_SIZE || cli->cl_ar.ar_force_sync ||
-            loi->loi_ar.ar_force_sync)
-                RETURN(-EDQUOT);
-
-        /* Hopefully normal case - cache space and write credits available */
-        if (cli->cl_dirty + CFS_PAGE_SIZE <= cli->cl_dirty_max &&
-            cfs_atomic_read(&obd_dirty_pages) + 1 <= obd_max_dirty_pages &&
-            osc_enter_cache_try(env, cli, loi, oap, 0))
-                RETURN(0);
-
-        /* It is safe to block as a cache waiter as long as there is grant
-         * space available or the hope of additional grant being returned
-         * when an in flight write completes.  Using the write back cache
-         * if possible is preferable to sending the data synchronously
-         * because write pages can then be merged in to large requests.
-         * The addition of this cache waiter will causing pending write
-         * pages to be sent immediately. */
-        if (cli->cl_w_in_flight || cli->cl_avail_grant >= CFS_PAGE_SIZE) {
-                cfs_list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
-                cfs_waitq_init(&ocw.ocw_waitq);
-                ocw.ocw_oap = oap;
-                ocw.ocw_rc = 0;
-
-                loi_list_maint(cli, loi);
-                osc_check_rpcs(env, cli);
-                client_obd_list_unlock(&cli->cl_loi_list_lock);
-
-                CDEBUG(D_CACHE, "sleeping for cache space\n");
-                l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
-
-                client_obd_list_lock(&cli->cl_loi_list_lock);
-                if (!cfs_list_empty(&ocw.ocw_entry)) {
-                        cfs_list_del(&ocw.ocw_entry);
-                        RETURN(-EINTR);
-                }
-                RETURN(ocw.ocw_rc);
-        }
-
-        RETURN(-EDQUOT);
-}
-
-
-int osc_prep_async_page(struct obd_export *exp, struct lov_stripe_md *lsm,
-                        struct lov_oinfo *loi, cfs_page_t *page,
-                        obd_off offset, const struct obd_async_page_ops *ops,
-                        void *data, void **res, int nocache,
-                        struct lustre_handle *lockh)
-{
-        struct osc_async_page *oap;
-
-        ENTRY;
-
-        if (!page)
-                return cfs_size_round(sizeof(*oap));
-
-        oap = *res;
-        oap->oap_magic = OAP_MAGIC;
-        oap->oap_cli = &exp->exp_obd->u.cli;
-        oap->oap_loi = loi;
-
-        oap->oap_caller_ops = ops;
-        oap->oap_caller_data = data;
-
-        oap->oap_page = page;
-        oap->oap_obj_off = offset;
-        if (!client_is_remote(exp) &&
-            cfs_capable(CFS_CAP_SYS_RESOURCE))
-                oap->oap_brw_flags = OBD_BRW_NOQUOTA;
-
-        LASSERT(!(offset & ~CFS_PAGE_MASK));
-
-        CFS_INIT_LIST_HEAD(&oap->oap_pending_item);
-        CFS_INIT_LIST_HEAD(&oap->oap_urgent_item);
-        CFS_INIT_LIST_HEAD(&oap->oap_rpc_item);
-        CFS_INIT_LIST_HEAD(&oap->oap_page_list);
-
-        cfs_spin_lock_init(&oap->oap_lock);
-        CDEBUG(D_CACHE, "oap %p page %p obj off "LPU64"\n", oap, page, offset);
-        RETURN(0);
-}
-
-struct osc_async_page *oap_from_cookie(void *cookie)
-{
-        struct osc_async_page *oap = cookie;
-        if (oap->oap_magic != OAP_MAGIC)
-                return ERR_PTR(-EINVAL);
-        return oap;
-};
-
-int osc_queue_async_io(const struct lu_env *env,
-                       struct obd_export *exp, struct lov_stripe_md *lsm,
-                       struct lov_oinfo *loi, void *cookie,
-                       int cmd, obd_off off, int count,
-                       obd_flag brw_flags, enum async_flags async_flags)
-{
-        struct client_obd *cli = &exp->exp_obd->u.cli;
-        struct osc_async_page *oap;
-        int rc = 0;
-        ENTRY;
-
-        oap = oap_from_cookie(cookie);
-        if (IS_ERR(oap))
-                RETURN(PTR_ERR(oap));
-
-        if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
-                RETURN(-EIO);
-
-        if (!cfs_list_empty(&oap->oap_pending_item) ||
-            !cfs_list_empty(&oap->oap_urgent_item) ||
-            !cfs_list_empty(&oap->oap_rpc_item))
-                RETURN(-EBUSY);
-
-        /* check if the file's owner/group is over quota */
-        if ((cmd & OBD_BRW_WRITE) && !(cmd & OBD_BRW_NOQUOTA)) {
-                struct cl_object *obj;
-                struct cl_attr    attr; /* XXX put attr into thread info */
-                unsigned int qid[MAXQUOTAS];
-
-                obj = cl_object_top(osc_oap2cl_page(oap)->cp_obj);
-
-                cl_object_attr_lock(obj);
-                rc = cl_object_attr_get(env, obj, &attr);
-                cl_object_attr_unlock(obj);
-
-                qid[USRQUOTA] = attr.cat_uid;
-                qid[GRPQUOTA] = attr.cat_gid;
-                if (rc == 0 &&
-                    lquota_chkdq(quota_interface, cli, qid) == NO_QUOTA)
-                        rc = -EDQUOT;
-                if (rc)
-                        RETURN(rc);
-        }
-
-        if (loi == NULL)
-                loi = lsm->lsm_oinfo[0];
-
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-
-        LASSERT(off + count <= CFS_PAGE_SIZE);
-        oap->oap_cmd = cmd;
-        oap->oap_page_off = off;
-        oap->oap_count = count;
-        oap->oap_brw_flags = brw_flags;
-        /* Give a hint to OST that requests are coming from kswapd - bug19529 */
-        if (cfs_memory_pressure_get())
-                oap->oap_brw_flags |= OBD_BRW_MEMALLOC;
-        cfs_spin_lock(&oap->oap_lock);
-        oap->oap_async_flags = async_flags;
-        cfs_spin_unlock(&oap->oap_lock);
-
-        if (cmd & OBD_BRW_WRITE) {
-                rc = osc_enter_cache(env, cli, loi, oap);
-                if (rc) {
-                        client_obd_list_unlock(&cli->cl_loi_list_lock);
-                        RETURN(rc);
-                }
-        }
-
-        osc_oap_to_pending(oap);
-        loi_list_maint(cli, loi);
-
-        LOI_DEBUG(loi, "oap %p page %p added for cmd %d\n", oap, oap->oap_page,
-                  cmd);
-
-        osc_check_rpcs(env, cli);
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
-
-        RETURN(0);
-}
-
-/* aka (~was & now & flag), but this is more clear :) */
-#define SETTING(was, now, flag) (!(was & flag) && (now & flag))
-
-int osc_set_async_flags_base(struct client_obd *cli,
-                             struct lov_oinfo *loi, struct osc_async_page *oap,
-                             obd_flag async_flags)
-{
-        struct loi_oap_pages *lop;
-        int flags = 0;
-        ENTRY;
-
-        LASSERT(!cfs_list_empty(&oap->oap_pending_item));
-
-        if (oap->oap_cmd & OBD_BRW_WRITE) {
-                lop = &loi->loi_write_lop;
-        } else {
-                lop = &loi->loi_read_lop;
-        }
-
-        if ((oap->oap_async_flags & async_flags) == async_flags)
-                RETURN(0);
-
-        if (SETTING(oap->oap_async_flags, async_flags, ASYNC_READY))
-                flags |= ASYNC_READY;
-
-        if (SETTING(oap->oap_async_flags, async_flags, ASYNC_URGENT) &&
-            cfs_list_empty(&oap->oap_rpc_item)) {
-                if (oap->oap_async_flags & ASYNC_HP)
-                        cfs_list_add(&oap->oap_urgent_item, &lop->lop_urgent);
-                else
-                        cfs_list_add_tail(&oap->oap_urgent_item,
-                                          &lop->lop_urgent);
-                flags |= ASYNC_URGENT;
-                loi_list_maint(cli, loi);
-        }
-        cfs_spin_lock(&oap->oap_lock);
-        oap->oap_async_flags |= flags;
-        cfs_spin_unlock(&oap->oap_lock);
-
-        LOI_DEBUG(loi, "oap %p page %p has flags %x\n", oap, oap->oap_page,
-                        oap->oap_async_flags);
-        RETURN(0);
-}
-
-int osc_teardown_async_page(struct obd_export *exp,
-                            struct lov_stripe_md *lsm,
-                            struct lov_oinfo *loi, void *cookie)
-{
-        struct client_obd *cli = &exp->exp_obd->u.cli;
-        struct loi_oap_pages *lop;
-        struct osc_async_page *oap;
-        int rc = 0;
-        ENTRY;
-
-        oap = oap_from_cookie(cookie);
-        if (IS_ERR(oap))
-                RETURN(PTR_ERR(oap));
-
-        if (loi == NULL)
-                loi = lsm->lsm_oinfo[0];
-
-        if (oap->oap_cmd & OBD_BRW_WRITE) {
-                lop = &loi->loi_write_lop;
-        } else {
-                lop = &loi->loi_read_lop;
-        }
-
-        client_obd_list_lock(&cli->cl_loi_list_lock);
-
-        if (!cfs_list_empty(&oap->oap_rpc_item))
-                GOTO(out, rc = -EBUSY);
-
-        osc_exit_cache(cli, oap, 0);
-        osc_wake_cache_waiters(cli);
-
-        if (!cfs_list_empty(&oap->oap_urgent_item)) {
-                cfs_list_del_init(&oap->oap_urgent_item);
-                cfs_spin_lock(&oap->oap_lock);
-                oap->oap_async_flags &= ~(ASYNC_URGENT | ASYNC_HP);
-                cfs_spin_unlock(&oap->oap_lock);
-        }
-        if (!cfs_list_empty(&oap->oap_pending_item)) {
-                cfs_list_del_init(&oap->oap_pending_item);
-                lop_update_pending(cli, lop, oap->oap_cmd, -1);
-        }
-        loi_list_maint(cli, loi);
-        LOI_DEBUG(loi, "oap %p page %p torn down\n", oap, oap->oap_page);
-out:
-        client_obd_list_unlock(&cli->cl_loi_list_lock);
-        RETURN(rc);
-}
+        lock_res_and_lock(lock);
+       spin_lock(&osc_ast_guard);
 
-static void osc_set_lock_data_with_check(struct ldlm_lock *lock,
-                                         struct ldlm_enqueue_info *einfo,
-                                         int flags)
-{
-        void *data = einfo->ei_cbdata;
+       if (lock->l_ast_data == NULL)
+               lock->l_ast_data = data;
+       if (lock->l_ast_data == data)
+               set = 1;
 
-        LASSERT(lock != NULL);
-        LASSERT(lock->l_blocking_ast == einfo->ei_cb_bl);
-        LASSERT(lock->l_resource->lr_type == einfo->ei_type);
-        LASSERT(lock->l_completion_ast == einfo->ei_cb_cp);
-        LASSERT(lock->l_glimpse_ast == einfo->ei_cb_gl);
+       spin_unlock(&osc_ast_guard);
+       unlock_res_and_lock(lock);
 
-        lock_res_and_lock(lock);
-        cfs_spin_lock(&osc_ast_guard);
-        LASSERT(lock->l_ast_data == NULL || lock->l_ast_data == data);
-        lock->l_ast_data = data;
-        cfs_spin_unlock(&osc_ast_guard);
-        unlock_res_and_lock(lock);
+       return set;
 }
 
-static void osc_set_data_with_check(struct lustre_handle *lockh,
-                                    struct ldlm_enqueue_info *einfo,
-                                    int flags)
+static int osc_set_data_with_check(struct lustre_handle *lockh,
+                                   struct ldlm_enqueue_info *einfo)
 {
         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
+        int set = 0;
 
         if (lock != NULL) {
-                osc_set_lock_data_with_check(lock, einfo, flags);
+                set = osc_set_lock_data_with_check(lock, einfo);
                 LDLM_LOCK_PUT(lock);
         } else
                 CERROR("lockh %p, data %p - client evicted?\n",
                        lockh, einfo->ei_cbdata);
+        return set;
 }
 
 static int osc_change_cbdata(struct obd_export *exp, struct lov_stripe_md *lsm,
@@ -3145,7 +2314,7 @@ static int osc_change_cbdata(struct obd_export *exp, struct lov_stripe_md *lsm,
         struct ldlm_res_id res_id;
         struct obd_device *obd = class_exp2obd(exp);
 
-        osc_build_res_name(lsm->lsm_object_id, lsm->lsm_object_seq, &res_id);
+       ostid_build_res_name(&lsm->lsm_oi, &res_id);
         ldlm_resource_iterate(obd->obd_namespace, &res_id, replace, data);
         return 0;
 }
@@ -3161,7 +2330,7 @@ static int osc_find_cbdata(struct obd_export *exp, struct lov_stripe_md *lsm,
         struct obd_device *obd = class_exp2obd(exp);
         int rc = 0;
 
-        osc_build_res_name(lsm->lsm_object_id, lsm->lsm_object_seq, &res_id);
+       ostid_build_res_name(&lsm->lsm_oi, &res_id);
         rc = ldlm_resource_iterate(obd->obd_namespace, &res_id, replace, data);
         if (rc == LDLM_ITER_STOP)
                 return(1);
@@ -3172,7 +2341,7 @@ static int osc_find_cbdata(struct obd_export *exp, struct lov_stripe_md *lsm,
 
 static int osc_enqueue_fini(struct ptlrpc_request *req, struct ost_lvb *lvb,
                             obd_enqueue_update_f upcall, void *cookie,
-                            int *flags, int rc)
+                           __u64 *flags, int agl, int rc)
 {
         int intent = *flags & LDLM_FL_HAS_INTENT;
         ENTRY;
@@ -3190,7 +2359,8 @@ static int osc_enqueue_fini(struct ptlrpc_request *req, struct ost_lvb *lvb,
                 }
         }
 
-        if ((intent && rc == ELDLM_LOCK_ABORTED) || !rc) {
+        if ((intent != 0 && rc == ELDLM_LOCK_ABORTED && agl == 0) ||
+            (rc == 0)) {
                 *flags |= LDLM_FL_LVB_READY;
                 CDEBUG(D_INODE,"got kms "LPU64" blocks "LPU64" mtime "LPU64"\n",
                        lvb->lvb_size, lvb->lvb_blocks, lvb->lvb_mtime);
@@ -3208,6 +2378,9 @@ static int osc_enqueue_interpret(const struct lu_env *env,
         struct ldlm_lock *lock;
         struct lustre_handle handle;
         __u32 mode;
+        struct ost_lvb *lvb;
+        __u32 lvb_len;
+       __u64 *flags = aa->oa_flags;
 
         /* Make a local copy of a lock handle and a mode, because aa->oa_*
          * might be freed anytime after lock upcall has been called. */
@@ -3227,13 +2400,20 @@ static int osc_enqueue_interpret(const struct lu_env *env,
         /* Let CP AST to grant the lock first. */
         OBD_FAIL_TIMEOUT(OBD_FAIL_OSC_CP_ENQ_RACE, 1);
 
+        if (aa->oa_agl && rc == ELDLM_LOCK_ABORTED) {
+                lvb = NULL;
+                lvb_len = 0;
+        } else {
+                lvb = aa->oa_lvb;
+                lvb_len = sizeof(*aa->oa_lvb);
+        }
+
         /* Complete obtaining the lock procedure. */
         rc = ldlm_cli_enqueue_fini(aa->oa_exp, req, aa->oa_ei->ei_type, 1,
-                                   mode, aa->oa_flags, aa->oa_lvb,
-                                   sizeof(*aa->oa_lvb), &handle, rc);
+                                   mode, flags, lvb, lvb_len, &handle, rc);
         /* Complete osc stuff. */
-        rc = osc_enqueue_fini(req, aa->oa_lvb,
-                              aa->oa_upcall, aa->oa_cookie, aa->oa_flags, rc);
+        rc = osc_enqueue_fini(req, aa->oa_lvb, aa->oa_upcall, aa->oa_cookie,
+                              flags, aa->oa_agl, rc);
 
         OBD_FAIL_TIMEOUT(OBD_FAIL_OSC_CP_CANCEL_RACE, 10);
 
@@ -3257,8 +2437,9 @@ void osc_update_enqueue(struct lustre_handle *lov_lockhp,
                         struct lov_oinfo *loi, int flags,
                         struct ost_lvb *lvb, __u32 mode, int rc)
 {
+        struct ldlm_lock *lock = ldlm_handle2lock(lov_lockhp);
+
         if (rc == ELDLM_OK) {
-                struct ldlm_lock *lock = ldlm_handle2lock(lov_lockhp);
                 __u64 tmp;
 
                 LASSERT(lock != NULL);
@@ -3279,13 +2460,21 @@ void osc_update_enqueue(struct lustre_handle *lov_lockhp,
                                    lock->l_policy_data.l_extent.end);
                 }
                 ldlm_lock_allow_match(lock);
-                LDLM_LOCK_PUT(lock);
         } else if (rc == ELDLM_LOCK_ABORTED && (flags & LDLM_FL_HAS_INTENT)) {
+                LASSERT(lock != NULL);
                 loi->loi_lvb = *lvb;
+                ldlm_lock_allow_match(lock);
                 CDEBUG(D_INODE, "glimpsed, setting rss="LPU64"; leaving"
                        " kms="LPU64"\n", loi->loi_lvb.lvb_size, loi->loi_kms);
                 rc = ELDLM_OK;
         }
+
+        if (lock != NULL) {
+                if (rc != ELDLM_OK)
+                        ldlm_lock_fail_match(lock);
+
+                LDLM_LOCK_PUT(lock);
+        }
 }
 EXPORT_SYMBOL(osc_update_enqueue);
 
@@ -3299,16 +2488,17 @@ struct ptlrpc_request_set *PTLRPCD_SET = (void *)1;
  * is excluded from the cluster -- such scenarious make the life difficult, so
  * release locks just after they are obtained. */
 int osc_enqueue_base(struct obd_export *exp, struct ldlm_res_id *res_id,
-                     int *flags, ldlm_policy_data_t *policy,
+                    __u64 *flags, ldlm_policy_data_t *policy,
                      struct ost_lvb *lvb, int kms_valid,
                      obd_enqueue_update_f upcall, void *cookie,
                      struct ldlm_enqueue_info *einfo,
                      struct lustre_handle *lockh,
-                     struct ptlrpc_request_set *rqset, int async)
+                     struct ptlrpc_request_set *rqset, int async, int agl)
 {
         struct obd_device *obd = exp->exp_obd;
         struct ptlrpc_request *req = NULL;
         int intent = *flags & LDLM_FL_HAS_INTENT;
+        int match_lvb = (agl != 0 ? 0 : LDLM_FL_LVB_READY);
         ldlm_mode_t mode;
         int rc;
         ENTRY;
@@ -3342,38 +2532,47 @@ int osc_enqueue_base(struct obd_export *exp, struct ldlm_res_id *res_id,
         mode = einfo->ei_mode;
         if (einfo->ei_mode == LCK_PR)
                 mode |= LCK_PW;
-        mode = ldlm_lock_match(obd->obd_namespace,
-                               *flags | LDLM_FL_LVB_READY, res_id,
+        mode = ldlm_lock_match(obd->obd_namespace, *flags | match_lvb, res_id,
                                einfo->ei_type, policy, mode, lockh, 0);
         if (mode) {
                 struct ldlm_lock *matched = ldlm_handle2lock(lockh);
 
-                if (matched->l_ast_data == NULL ||
-                    matched->l_ast_data == einfo->ei_cbdata) {
+                if ((agl != 0) && !(matched->l_flags & LDLM_FL_LVB_READY)) {
+                        /* For AGL, if enqueue RPC is sent but the lock is not
+                         * granted, then skip to process this strpe.
+                         * Return -ECANCELED to tell the caller. */
+                        ldlm_lock_decref(lockh, mode);
+                        LDLM_LOCK_PUT(matched);
+                        RETURN(-ECANCELED);
+                } else if (osc_set_lock_data_with_check(matched, einfo)) {
+                        *flags |= LDLM_FL_LVB_READY;
                         /* addref the lock only if not async requests and PW
                          * lock is matched whereas we asked for PR. */
                         if (!rqset && einfo->ei_mode != mode)
                                 ldlm_lock_addref(lockh, LCK_PR);
-                        osc_set_lock_data_with_check(matched, einfo, *flags);
                         if (intent) {
                                 /* I would like to be able to ASSERT here that
                                  * rss <= kms, but I can't, for reasons which
                                  * are explained in lov_enqueue() */
                         }
 
-                        /* We already have a lock, and it's referenced */
+                       /* We already have a lock, and it's referenced.
+                        *
+                        * At this point, the cl_lock::cll_state is CLS_QUEUING,
+                        * AGL upcall may change it to CLS_HELD directly. */
                         (*upcall)(cookie, ELDLM_OK);
 
-                        /* For async requests, decref the lock. */
                         if (einfo->ei_mode != mode)
                                 ldlm_lock_decref(lockh, LCK_PW);
                         else if (rqset)
+                                /* For async requests, decref the lock. */
                                 ldlm_lock_decref(lockh, einfo->ei_mode);
                         LDLM_LOCK_PUT(matched);
                         RETURN(ELDLM_OK);
-                } else
+                } else {
                         ldlm_lock_decref(lockh, mode);
-                LDLM_LOCK_PUT(matched);
+                        LDLM_LOCK_PUT(matched);
+                }
         }
 
  no_match:
@@ -3399,7 +2598,7 @@ int osc_enqueue_base(struct obd_export *exp, struct ldlm_res_id *res_id,
         *flags &= ~LDLM_FL_BLOCK_GRANTED;
 
         rc = ldlm_cli_enqueue(exp, &req, einfo, res_id, policy, flags, lvb,
-                              sizeof(*lvb), lockh, async);
+                             sizeof(*lvb), LVB_T_OST, lockh, async);
         if (rqset) {
                 if (!rc) {
                         struct osc_enqueue_args *aa;
@@ -3412,11 +2611,12 @@ int osc_enqueue_base(struct obd_export *exp, struct ldlm_res_id *res_id,
                         aa->oa_cookie = cookie;
                         aa->oa_lvb    = lvb;
                         aa->oa_lockh  = lockh;
+                        aa->oa_agl    = !!agl;
 
                         req->rq_interpret_reply =
                                 (ptlrpc_interpterer_t)osc_enqueue_interpret;
                         if (rqset == PTLRPCD_SET)
-                                ptlrpcd_add_req(req, PSCOPE_OTHER);
+                                ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
                         else
                                 ptlrpc_set_add_req(rqset, req);
                 } else if (intent) {
@@ -3425,7 +2625,7 @@ int osc_enqueue_base(struct obd_export *exp, struct ldlm_res_id *res_id,
                 RETURN(rc);
         }
 
-        rc = osc_enqueue_fini(req, lvb, upcall, cookie, flags, rc);
+        rc = osc_enqueue_fini(req, lvb, upcall, cookie, flags, agl, rc);
         if (intent)
                 ptlrpc_req_finished(req);
 
@@ -3440,14 +2640,12 @@ static int osc_enqueue(struct obd_export *exp, struct obd_info *oinfo,
         int rc;
         ENTRY;
 
-        osc_build_res_name(oinfo->oi_md->lsm_object_id,
-                           oinfo->oi_md->lsm_object_seq, &res_id);
-
+       ostid_build_res_name(&oinfo->oi_md->lsm_oi, &res_id);
         rc = osc_enqueue_base(exp, &res_id, &oinfo->oi_flags, &oinfo->oi_policy,
                               &oinfo->oi_md->lsm_oinfo[0]->loi_lvb,
                               oinfo->oi_md->lsm_oinfo[0]->loi_kms_valid,
                               oinfo->oi_cb_up, oinfo, einfo, oinfo->oi_lockh,
-                              rqset, rqset != NULL);
+                              rqset, rqset != NULL, 0);
         RETURN(rc);
 }
 
@@ -3479,8 +2677,13 @@ int osc_match_base(struct obd_export *exp, struct ldlm_res_id *res_id,
         rc = ldlm_lock_match(obd->obd_namespace, lflags,
                              res_id, type, policy, rc, lockh, unref);
         if (rc) {
-                if (data != NULL)
-                        osc_set_data_with_check(lockh, data, lflags);
+                if (data != NULL) {
+                        if (!osc_set_data_with_check(lockh, data)) {
+                                if (!(lflags & LDLM_FL_TEST_LOCK))
+                                        ldlm_lock_decref(lockh, rc);
+                                RETURN(0);
+                        }
+                }
                 if (!(lflags & LDLM_FL_TEST_LOCK) && mode != rc) {
                         ldlm_lock_addref(lockh, LCK_PR);
                         ldlm_lock_decref(lockh, LCK_PW);
@@ -3517,10 +2720,10 @@ static int osc_cancel_unused(struct obd_export *exp,
         struct obd_device *obd = class_exp2obd(exp);
         struct ldlm_res_id res_id, *resp = NULL;
 
-        if (lsm != NULL) {
-                resp = osc_build_res_name(lsm->lsm_object_id,
-                                          lsm->lsm_object_seq, &res_id);
-        }
+       if (lsm != NULL) {
+               ostid_build_res_name(&lsm->lsm_oi, &res_id);
+               resp = &res_id;
+       }
 
         return ldlm_cli_cancel_unused(obd->obd_namespace, resp, flags, opaque);
 }
@@ -3529,9 +2732,7 @@ static int osc_statfs_interpret(const struct lu_env *env,
                                 struct ptlrpc_request *req,
                                 struct osc_async_args *aa, int rc)
 {
-        struct client_obd *cli = &req->rq_import->imp_obd->u.cli;
         struct obd_statfs *msfs;
-        __u64 used;
         ENTRY;
 
         if (rc == -EBADR)
@@ -3554,53 +2755,17 @@ static int osc_statfs_interpret(const struct lu_env *env,
                 GOTO(out, rc = -EPROTO);
         }
 
-        /* Reinitialize the RDONLY and DEGRADED flags at the client
-         * on each statfs, so they don't stay set permanently. */
-        cfs_spin_lock(&cli->cl_oscc.oscc_lock);
-
-        if (unlikely(msfs->os_state & OS_STATE_DEGRADED))
-                cli->cl_oscc.oscc_flags |= OSCC_FLAG_DEGRADED;
-        else if (unlikely(cli->cl_oscc.oscc_flags & OSCC_FLAG_DEGRADED))
-                cli->cl_oscc.oscc_flags &= ~OSCC_FLAG_DEGRADED;
-
-        if (unlikely(msfs->os_state & OS_STATE_READONLY))
-                cli->cl_oscc.oscc_flags |= OSCC_FLAG_RDONLY;
-        else if (unlikely(cli->cl_oscc.oscc_flags & OSCC_FLAG_RDONLY))
-                cli->cl_oscc.oscc_flags &= ~OSCC_FLAG_RDONLY;
-
-        /* Add a bit of hysteresis so this flag isn't continually flapping,
-         * and ensure that new files don't get extremely fragmented due to
-         * only a small amount of available space in the filesystem.
-         * We want to set the NOSPC flag when there is less than ~0.1% free
-         * and clear it when there is at least ~0.2% free space, so:
-         *                   avail < ~0.1% max          max = avail + used
-         *            1025 * avail < avail + used       used = blocks - free
-         *            1024 * avail < used
-         *            1024 * avail < blocks - free                      
-         *                   avail < ((blocks - free) >> 10)    
-         *
-         * On very large disk, say 16TB 0.1% will be 16 GB. We don't want to
-         * lose that amount of space so in those cases we report no space left
-         * if their is less than 1 GB left.                             */
-        used = min_t(__u64,(msfs->os_blocks - msfs->os_bfree) >> 10, 1 << 30);
-        if (unlikely(((cli->cl_oscc.oscc_flags & OSCC_FLAG_NOSPC) == 0) &&
-                     ((msfs->os_ffree < 32) || (msfs->os_bavail < used))))
-                cli->cl_oscc.oscc_flags |= OSCC_FLAG_NOSPC;
-        else if (unlikely(((cli->cl_oscc.oscc_flags & OSCC_FLAG_NOSPC) != 0) &&
-                (msfs->os_ffree > 64) && (msfs->os_bavail > (used << 1))))
-                        cli->cl_oscc.oscc_flags &= ~OSCC_FLAG_NOSPC;
-
-        cfs_spin_unlock(&cli->cl_oscc.oscc_lock);
-
         *aa->aa_oi->oi_osfs = *msfs;
 out:
         rc = aa->aa_oi->oi_cb_up(aa->aa_oi, rc);
         RETURN(rc);
 }
 
-static int osc_statfs_async(struct obd_device *obd, struct obd_info *oinfo,
-                            __u64 max_age, struct ptlrpc_request_set *rqset)
+static int osc_statfs_async(struct obd_export *exp,
+                            struct obd_info *oinfo, __u64 max_age,
+                            struct ptlrpc_request_set *rqset)
 {
+        struct obd_device     *obd = class_exp2obd(exp);
         struct ptlrpc_request *req;
         struct osc_async_args *aa;
         int                    rc;
@@ -3640,9 +2805,10 @@ static int osc_statfs_async(struct obd_device *obd, struct obd_info *oinfo,
         RETURN(0);
 }
 
-static int osc_statfs(struct obd_device *obd, struct obd_statfs *osfs,
-                      __u64 max_age, __u32 flags)
+static int osc_statfs(const struct lu_env *env, struct obd_export *exp,
+                      struct obd_statfs *osfs, __u64 max_age, __u32 flags)
 {
+        struct obd_device     *obd = class_exp2obd(exp);
         struct obd_statfs     *msfs;
         struct ptlrpc_request *req;
         struct obd_import     *imp = NULL;
@@ -3651,10 +2817,10 @@ static int osc_statfs(struct obd_device *obd, struct obd_statfs *osfs,
 
         /*Since the request might also come from lprocfs, so we need
          *sync this with client_disconnect_export Bug15684*/
-        cfs_down_read(&obd->u.cli.cl_sem);
+       down_read(&obd->u.cli.cl_sem);
         if (obd->u.cli.cl_import)
                 imp = class_import_get(obd->u.cli.cl_import);
-        cfs_up_read(&obd->u.cli.cl_sem);
+       up_read(&obd->u.cli.cl_sem);
         if (!imp)
                 RETURN(-ENODEV);
 
@@ -3743,18 +2909,18 @@ static int osc_getstripe(struct lov_stripe_md *lsm, struct lov_user_md *lump)
                 if (!lumk)
                         RETURN(-ENOMEM);
 
-                if (lum.lmm_magic == LOV_USER_MAGIC_V1)
-                        lmm_objects = &(((struct lov_user_md_v1 *)lumk)->lmm_objects[0]);
-                else
-                        lmm_objects = &(lumk->lmm_objects[0]);
-                lmm_objects->l_object_id = lsm->lsm_object_id;
-        } else {
-                lum_size = lov_mds_md_size(0, lum.lmm_magic);
-                lumk = &lum;
-        }
-
-        lumk->lmm_object_id = lsm->lsm_object_id;
-        lumk->lmm_object_seq = lsm->lsm_object_seq;
+               if (lum.lmm_magic == LOV_USER_MAGIC_V1)
+                       lmm_objects =
+                           &(((struct lov_user_md_v1 *)lumk)->lmm_objects[0]);
+               else
+                       lmm_objects = &(lumk->lmm_objects[0]);
+               lmm_objects->l_ost_oi = lsm->lsm_oi;
+       } else {
+               lum_size = lov_mds_md_size(0, lum.lmm_magic);
+               lumk = &lum;
+       }
+
+       lumk->lmm_oi = lsm->lsm_oi;
         lumk->lmm_stripe_count = 1;
 
         if (cfs_copy_to_user(lump, lumk, lum_size))
@@ -3829,7 +2995,7 @@ static int osc_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
                 GOTO(out, err);
         case OBD_IOC_CLIENT_RECOVER:
                 err = ptlrpc_recover_import(obd->u.cli.cl_import,
-                                            data->ioc_inlbuf1);
+                                            data->ioc_inlbuf1, 0);
                 if (err > 0)
                         err = 0;
                 GOTO(out, err);
@@ -3838,8 +3004,7 @@ static int osc_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
                                                data->ioc_offset);
                 GOTO(out, err);
         case OBD_IOC_POLL_QUOTACHECK:
-                err = lquota_poll_check(quota_interface, exp,
-                                        (struct if_quotacheck *)karg);
+                err = osc_quota_poll_check(exp, (struct if_quotacheck *)karg);
                 GOTO(out, err);
         case OBD_IOC_PING_TARGET:
                 err = ptlrpc_obd_ping(obd);
@@ -3854,8 +3019,8 @@ out:
         return err;
 }
 
-static int osc_get_info(struct obd_export *exp, obd_count keylen,
-                        void *key, __u32 *vallen, void *val,
+static int osc_get_info(const struct lu_env *env, struct obd_export *exp,
+                        obd_count keylen, void *key, __u32 *vallen, void *val,
                         struct lov_stripe_md *lsm)
 {
         ENTRY;
@@ -3951,43 +3116,9 @@ static int osc_get_info(struct obd_export *exp, obd_count keylen,
         RETURN(-EINVAL);
 }
 
-static int osc_setinfo_mds_connect_import(struct obd_import *imp)
-{
-        struct llog_ctxt *ctxt;
-        int rc = 0;
-        ENTRY;
-
-        ctxt = llog_get_context(imp->imp_obd, LLOG_MDS_OST_ORIG_CTXT);
-        if (ctxt) {
-                rc = llog_initiator_connect(ctxt);
-                llog_ctxt_put(ctxt);
-        } else {
-                /* XXX return an error? skip setting below flags? */
-        }
-
-        cfs_spin_lock(&imp->imp_lock);
-        imp->imp_server_timeout = 1;
-        imp->imp_pingable = 1;
-        cfs_spin_unlock(&imp->imp_lock);
-        CDEBUG(D_RPCTRACE, "pinging OST %s\n", obd2cli_tgt(imp->imp_obd));
-
-        RETURN(rc);
-}
-
-static int osc_setinfo_mds_conn_interpret(const struct lu_env *env,
-                                          struct ptlrpc_request *req,
-                                          void *aa, int rc)
-{
-        ENTRY;
-        if (rc != 0)
-                RETURN(rc);
-
-        RETURN(osc_setinfo_mds_connect_import(req->rq_import));
-}
-
-static int osc_set_info_async(struct obd_export *exp, obd_count keylen,
-                              void *key, obd_count vallen, void *val,
-                              struct ptlrpc_request_set *set)
+static int osc_set_info_async(const struct lu_env *env, struct obd_export *exp,
+                              obd_count keylen, void *key, obd_count vallen,
+                              void *val, struct ptlrpc_request_set *set)
 {
         struct ptlrpc_request *req;
         struct obd_device     *obd = exp->exp_obd;
@@ -3998,32 +3129,6 @@ static int osc_set_info_async(struct obd_export *exp, obd_count keylen,
 
         OBD_FAIL_TIMEOUT(OBD_FAIL_OSC_SHUTDOWN, 10);
 
-        if (KEY_IS(KEY_NEXT_ID)) {
-                obd_id new_val;
-                struct osc_creator *oscc = &obd->u.cli.cl_oscc;
-
-                if (vallen != sizeof(obd_id))
-                        RETURN(-ERANGE);
-                if (val == NULL)
-                        RETURN(-EINVAL);
-
-                if (vallen != sizeof(obd_id))
-                        RETURN(-EINVAL);
-
-                /* avoid race between allocate new object and set next id
-                 * from ll_sync thread */
-                cfs_spin_lock(&oscc->oscc_lock);
-                new_val = *((obd_id*)val) + 1;
-                if (new_val > oscc->oscc_next_id)
-                        oscc->oscc_next_id = new_val;
-                cfs_spin_unlock(&oscc->oscc_lock);
-                CDEBUG(D_HA, "%s: set oscc_next_id = "LPU64"\n",
-                       exp->exp_obd->obd_name,
-                       obd->u.cli.cl_oscc.oscc_next_id);
-
-                RETURN(0);
-        }
-
         if (KEY_IS(KEY_CHECKSUM)) {
                 if (vallen != sizeof(int))
                         RETURN(-EINVAL);
@@ -4041,6 +3146,33 @@ static int osc_set_info_async(struct obd_export *exp, obd_count keylen,
                 RETURN(0);
         }
 
+       if (KEY_IS(KEY_CACHE_SET)) {
+               struct client_obd *cli = &obd->u.cli;
+
+               LASSERT(cli->cl_cache == NULL); /* only once */
+               cli->cl_cache = (struct cl_client_cache *)val;
+               cfs_atomic_inc(&cli->cl_cache->ccc_users);
+               cli->cl_lru_left = &cli->cl_cache->ccc_lru_left;
+
+               /* add this osc into entity list */
+               LASSERT(cfs_list_empty(&cli->cl_lru_osc));
+               spin_lock(&cli->cl_cache->ccc_lru_lock);
+               cfs_list_add(&cli->cl_lru_osc, &cli->cl_cache->ccc_lru);
+               spin_unlock(&cli->cl_cache->ccc_lru_lock);
+
+               RETURN(0);
+       }
+
+       if (KEY_IS(KEY_CACHE_LRU_SHRINK)) {
+               struct client_obd *cli = &obd->u.cli;
+               int nr = cfs_atomic_read(&cli->cl_lru_in_list) >> 1;
+               int target = *(int *)val;
+
+               nr = osc_lru_shrink(cli, min(nr, target));
+               *(int *)val -= nr;
+               RETURN(0);
+       }
+
         if (!set && !KEY_IS(KEY_GRANT_SHRINK))
                 RETURN(-EINVAL);
 
@@ -4051,38 +3183,31 @@ static int osc_set_info_async(struct obd_export *exp, obd_count keylen,
            Even if something bad goes through, we'd get a -EINVAL from OST
            anyway. */
 
-        if (KEY_IS(KEY_GRANT_SHRINK))
-                req = ptlrpc_request_alloc(imp, &RQF_OST_SET_GRANT_INFO);
-        else
-                req = ptlrpc_request_alloc(imp, &RQF_OBD_SET_INFO);
-
-        if (req == NULL)
-                RETURN(-ENOMEM);
-
-        req_capsule_set_size(&req->rq_pill, &RMF_SETINFO_KEY,
-                             RCL_CLIENT, keylen);
-        req_capsule_set_size(&req->rq_pill, &RMF_SETINFO_VAL,
-                             RCL_CLIENT, vallen);
-        rc = ptlrpc_request_pack(req, LUSTRE_OST_VERSION, OST_SET_INFO);
-        if (rc) {
-                ptlrpc_request_free(req);
-                RETURN(rc);
-        }
-
-        tmp = req_capsule_client_get(&req->rq_pill, &RMF_SETINFO_KEY);
-        memcpy(tmp, key, keylen);
-        tmp = req_capsule_client_get(&req->rq_pill, &RMF_SETINFO_VAL);
+       req = ptlrpc_request_alloc(imp, KEY_IS(KEY_GRANT_SHRINK) ?
+                                               &RQF_OST_SET_GRANT_INFO :
+                                               &RQF_OBD_SET_INFO);
+       if (req == NULL)
+               RETURN(-ENOMEM);
+
+       req_capsule_set_size(&req->rq_pill, &RMF_SETINFO_KEY,
+                            RCL_CLIENT, keylen);
+       if (!KEY_IS(KEY_GRANT_SHRINK))
+               req_capsule_set_size(&req->rq_pill, &RMF_SETINFO_VAL,
+                                    RCL_CLIENT, vallen);
+       rc = ptlrpc_request_pack(req, LUSTRE_OST_VERSION, OST_SET_INFO);
+       if (rc) {
+               ptlrpc_request_free(req);
+               RETURN(rc);
+       }
+
+       tmp = req_capsule_client_get(&req->rq_pill, &RMF_SETINFO_KEY);
+       memcpy(tmp, key, keylen);
+       tmp = req_capsule_client_get(&req->rq_pill, KEY_IS(KEY_GRANT_SHRINK) ?
+                                                       &RMF_OST_BODY :
+                                                       &RMF_SETINFO_VAL);
         memcpy(tmp, val, vallen);
 
-        if (KEY_IS(KEY_MDS_CONN)) {
-                struct osc_creator *oscc = &obd->u.cli.cl_oscc;
-
-                oscc->oscc_oa.o_seq = (*(__u32 *)val);
-                oscc->oscc_oa.o_valid |= OBD_MD_FLGROUP;
-                LASSERT_SEQ_IS_MDT(oscc->oscc_oa.o_seq);
-                req->rq_no_delay = req->rq_no_resend = 1;
-                req->rq_interpret_reply = osc_setinfo_mds_conn_interpret;
-        } else if (KEY_IS(KEY_GRANT_SHRINK)) {
+       if (KEY_IS(KEY_GRANT_SHRINK)) {
                 struct osc_grant_args *aa;
                 struct obdo *oa;
 
@@ -4104,107 +3229,37 @@ static int osc_set_info_async(struct obd_export *exp, obd_count keylen,
                 ptlrpc_set_add_req(set, req);
                 ptlrpc_check_set(NULL, set);
         } else
-                ptlrpcd_add_req(req, PSCOPE_OTHER);
+                ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
 
         RETURN(0);
 }
 
 
-static struct llog_operations osc_size_repl_logops = {
-        lop_cancel: llog_obd_repl_cancel
-};
-
-static struct llog_operations osc_mds_ost_orig_logops;
-
-static int __osc_llog_init(struct obd_device *obd, struct obd_llog_group *olg,
-                           struct obd_device *tgt, struct llog_catid *catid)
-{
-        int rc;
-        ENTRY;
-
-        rc = llog_setup(obd, &obd->obd_olg, LLOG_MDS_OST_ORIG_CTXT, tgt, 1,
-                        &catid->lci_logid, &osc_mds_ost_orig_logops);
-        if (rc) {
-                CERROR("failed LLOG_MDS_OST_ORIG_CTXT\n");
-                GOTO(out, rc);
-        }
-
-        rc = llog_setup(obd, &obd->obd_olg, LLOG_SIZE_REPL_CTXT, tgt, 1,
-                        NULL, &osc_size_repl_logops);
-        if (rc) {
-                struct llog_ctxt *ctxt =
-                        llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT);
-                if (ctxt)
-                        llog_cleanup(ctxt);
-                CERROR("failed LLOG_SIZE_REPL_CTXT\n");
-        }
-        GOTO(out, rc);
-out:
-        if (rc) {
-                CERROR("osc '%s' tgt '%s' catid %p rc=%d\n",
-                       obd->obd_name, tgt->obd_name, catid, rc);
-                CERROR("logid "LPX64":0x%x\n",
-                       catid->lci_logid.lgl_oid, catid->lci_logid.lgl_ogen);
-        }
-        return rc;
-}
-
 static int osc_llog_init(struct obd_device *obd, struct obd_llog_group *olg,
                          struct obd_device *disk_obd, int *index)
 {
-        struct llog_catid catid;
-        static char name[32] = CATLIST;
-        int rc;
-        ENTRY;
-
-        LASSERT(olg == &obd->obd_olg);
-
-        cfs_mutex_down(&olg->olg_cat_processing);
-        rc = llog_get_cat_list(disk_obd, name, *index, 1, &catid);
-        if (rc) {
-                CERROR("rc: %d\n", rc);
-                GOTO(out, rc);
-        }
-
-        CDEBUG(D_INFO, "%s: Init llog for %d - catid "LPX64"/"LPX64":%x\n",
-               obd->obd_name, *index, catid.lci_logid.lgl_oid,
-               catid.lci_logid.lgl_oseq, catid.lci_logid.lgl_ogen);
-
-        rc = __osc_llog_init(obd, olg, disk_obd, &catid);
-        if (rc) {
-                CERROR("rc: %d\n", rc);
-                GOTO(out, rc);
-        }
-
-        rc = llog_put_cat_list(disk_obd, name, *index, 1, &catid);
-        if (rc) {
-                CERROR("rc: %d\n", rc);
-                GOTO(out, rc);
-        }
-
- out:
-        cfs_mutex_up(&olg->olg_cat_processing);
-
-        return rc;
+       /* this code is not supposed to be used with LOD/OSP
+        * to be removed soon */
+       LBUG();
+       return 0;
 }
 
 static int osc_llog_finish(struct obd_device *obd, int count)
 {
-        struct llog_ctxt *ctxt;
-        int rc = 0, rc2 = 0;
-        ENTRY;
+       struct llog_ctxt *ctxt;
 
-        ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT);
-        if (ctxt)
-                rc = llog_cleanup(ctxt);
+       ENTRY;
 
-        ctxt = llog_get_context(obd, LLOG_SIZE_REPL_CTXT);
-        if (ctxt)
-                rc2 = llog_cleanup(ctxt);
-        if (!rc)
-                rc = rc2;
+       ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT);
+       if (ctxt) {
+               llog_cat_close(NULL, ctxt->loc_handle);
+               llog_cleanup(NULL, ctxt);
+       }
 
-        RETURN(rc);
+       ctxt = llog_get_context(obd, LLOG_SIZE_REPL_CTXT);
+       if (ctxt)
+               llog_cleanup(NULL, ctxt);
+       RETURN(0);
 }
 
 static int osc_reconnect(const struct lu_env *env,
@@ -4220,20 +3275,17 @@ static int osc_reconnect(const struct lu_env *env,
 
                 client_obd_list_lock(&cli->cl_loi_list_lock);
                 data->ocd_grant = (cli->cl_avail_grant + cli->cl_dirty) ?:
-                                2 * cli->cl_max_pages_per_rpc << CFS_PAGE_SHIFT;
+                               2 * cli_brw_size(obd);
                 lost_grant = cli->cl_lost_grant;
                 cli->cl_lost_grant = 0;
                 client_obd_list_unlock(&cli->cl_loi_list_lock);
 
-                CDEBUG(D_CACHE, "request ocd_grant: %d cl_avail_grant: %ld "
-                       "cl_dirty: %ld cl_lost_grant: %ld\n", data->ocd_grant,
-                       cli->cl_avail_grant, cli->cl_dirty, lost_grant);
                 CDEBUG(D_RPCTRACE, "ocd_connect_flags: "LPX64" ocd_version: %d"
-                       " ocd_grant: %d\n", data->ocd_connect_flags,
-                       data->ocd_version, data->ocd_grant);
-        }
+                      " ocd_grant: %d, lost: %ld.\n", data->ocd_connect_flags,
+                      data->ocd_version, data->ocd_grant, lost_grant);
+       }
 
-        RETURN(0);
+       RETURN(0);
 }
 
 static int osc_disconnect(struct obd_export *exp)
@@ -4247,7 +3299,7 @@ static int osc_disconnect(struct obd_export *exp)
                 if (obd->u.cli.cl_conn_count == 1) {
                         /* Flush any remaining cancel messages out to the
                          * target */
-                        llog_sync(ctxt, exp);
+                       llog_sync(ctxt, exp, 0);
                 }
                 llog_ctxt_put(ctxt);
         } else {
@@ -4290,14 +3342,6 @@ static int osc_import_event(struct obd_device *obd,
 
         switch (event) {
         case IMP_EVENT_DISCON: {
-                /* Only do this on the MDS OSC's */
-                if (imp->imp_server_timeout) {
-                        struct osc_creator *oscc = &obd->u.cli.cl_oscc;
-
-                        cfs_spin_lock(&oscc->oscc_lock);
-                        oscc->oscc_flags |= OSCC_FLAG_RECOVERING;
-                        cfs_spin_unlock(&oscc->oscc_lock);
-                }
                 cli = &obd->u.cli;
                 client_obd_list_lock(&cli->cl_loi_list_lock);
                 cli->cl_avail_grant = 0;
@@ -4318,11 +3362,9 @@ static int osc_import_event(struct obd_device *obd,
                 if (!IS_ERR(env)) {
                         /* Reset grants */
                         cli = &obd->u.cli;
-                        client_obd_list_lock(&cli->cl_loi_list_lock);
                         /* all pages go to failing rpcs due to the invalid
                          * import */
-                        osc_check_rpcs(env, cli);
-                        client_obd_list_unlock(&cli->cl_loi_list_lock);
+                       osc_io_unplug(env, cli, NULL, PDL_POLICY_ROUND);
 
                         ldlm_namespace_cleanup(ns, LDLM_FL_LOCAL_ONLY);
                         cl_env_put(env, &refcheck);
@@ -4331,14 +3373,6 @@ static int osc_import_event(struct obd_device *obd,
                 break;
         }
         case IMP_EVENT_ACTIVE: {
-                /* Only do this on the MDS OSC's */
-                if (imp->imp_server_timeout) {
-                        struct osc_creator *oscc = &obd->u.cli.cl_oscc;
-
-                        cfs_spin_lock(&oscc->oscc_lock);
-                        oscc->oscc_flags &= ~OSCC_FLAG_NOSPC;
-                        cfs_spin_unlock(&oscc->oscc_lock);
-                }
                 rc = obd_notify_observer(obd, obd, OBD_NOTIFY_ACTIVE, NULL);
                 break;
         }
@@ -4355,6 +3389,14 @@ static int osc_import_event(struct obd_device *obd,
                 rc = obd_notify_observer(obd, obd, OBD_NOTIFY_OCD, NULL);
                 break;
         }
+        case IMP_EVENT_DEACTIVATE: {
+                rc = obd_notify_observer(obd, obd, OBD_NOTIFY_DEACTIVATE, NULL);
+                break;
+        }
+        case IMP_EVENT_ACTIVATE: {
+                rc = obd_notify_observer(obd, obd, OBD_NOTIFY_ACTIVATE, NULL);
+                break;
+        }
         default:
                 CERROR("Unknown import event %d\n", event);
                 LBUG();
@@ -4362,47 +3404,96 @@ static int osc_import_event(struct obd_device *obd,
         RETURN(rc);
 }
 
-int osc_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
+/**
+ * Determine whether the lock can be canceled before replaying the lock
+ * during recovery, see bug16774 for detailed information.
+ *
+ * \retval zero the lock can't be canceled
+ * \retval other ok to cancel
+ */
+static int osc_cancel_for_recovery(struct ldlm_lock *lock)
 {
-        int rc;
-        ENTRY;
+        check_res_locked(lock->l_resource);
 
-        ENTRY;
-        rc = ptlrpcd_addref();
-        if (rc)
-                RETURN(rc);
+        /*
+         * Cancel all unused extent lock in granted mode LCK_PR or LCK_CR.
+         *
+         * XXX as a future improvement, we can also cancel unused write lock
+         * if it doesn't have dirty data and active mmaps.
+         */
+        if (lock->l_resource->lr_type == LDLM_EXTENT &&
+            (lock->l_granted_mode == LCK_PR ||
+             lock->l_granted_mode == LCK_CR) &&
+            (osc_dlm_lock_pageref(lock) == 0))
+                RETURN(1);
 
-        rc = client_obd_setup(obd, lcfg);
-        if (rc) {
-                ptlrpcd_decref();
-        } else {
-                struct lprocfs_static_vars lvars = { 0 };
-                struct client_obd *cli = &obd->u.cli;
+        RETURN(0);
+}
 
-                cli->cl_grant_shrink_interval = GRANT_SHRINK_INTERVAL;
-                lprocfs_osc_init_vars(&lvars);
-                if (lprocfs_obd_setup(obd, lvars.obd_vars) == 0) {
-                        lproc_osc_attach_seqstat(obd);
-                        sptlrpc_lprocfs_cliobd_attach(obd);
-                        ptlrpc_lprocfs_register_obd(obd);
-                }
+static int brw_queue_work(const struct lu_env *env, void *data)
+{
+       struct client_obd *cli = data;
 
-                oscc_init(obd);
-                /* We need to allocate a few requests more, because
-                   brw_interpret tries to create new requests before freeing
-                   previous ones. Ideally we want to have 2x max_rpcs_in_flight
-                   reserved, but I afraid that might be too much wasted RAM
-                   in fact, so 2 is just my guess and still should work. */
-                cli->cl_import->imp_rq_pool =
-                        ptlrpc_init_rq_pool(cli->cl_max_rpcs_in_flight + 2,
-                                            OST_MAXREQSIZE,
-                                            ptlrpc_add_rqs_to_pool);
-
-                CFS_INIT_LIST_HEAD(&cli->cl_grant_shrink_list);
-                cfs_sema_init(&cli->cl_grant_sem, 1);
-        }
+       CDEBUG(D_CACHE, "Run writeback work for client obd %p.\n", cli);
 
-        RETURN(rc);
+       osc_io_unplug(env, cli, NULL, PDL_POLICY_SAME);
+       RETURN(0);
+}
+
+int osc_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
+{
+       struct lprocfs_static_vars lvars = { 0 };
+       struct client_obd          *cli = &obd->u.cli;
+       void                       *handler;
+       int                        rc;
+       ENTRY;
+
+       rc = ptlrpcd_addref();
+       if (rc)
+               RETURN(rc);
+
+       rc = client_obd_setup(obd, lcfg);
+       if (rc)
+               GOTO(out_ptlrpcd, rc);
+
+       handler = ptlrpcd_alloc_work(cli->cl_import, brw_queue_work, cli);
+       if (IS_ERR(handler))
+               GOTO(out_client_setup, rc = PTR_ERR(handler));
+       cli->cl_writeback_work = handler;
+
+       rc = osc_quota_setup(obd);
+       if (rc)
+               GOTO(out_ptlrpcd_work, rc);
+
+       cli->cl_grant_shrink_interval = GRANT_SHRINK_INTERVAL;
+       lprocfs_osc_init_vars(&lvars);
+       if (lprocfs_obd_setup(obd, lvars.obd_vars) == 0) {
+               lproc_osc_attach_seqstat(obd);
+               sptlrpc_lprocfs_cliobd_attach(obd);
+               ptlrpc_lprocfs_register_obd(obd);
+       }
+
+       /* We need to allocate a few requests more, because
+        * brw_interpret tries to create new requests before freeing
+        * previous ones, Ideally we want to have 2x max_rpcs_in_flight
+        * reserved, but I'm afraid that might be too much wasted RAM
+        * in fact, so 2 is just my guess and still should work. */
+       cli->cl_import->imp_rq_pool =
+               ptlrpc_init_rq_pool(cli->cl_max_rpcs_in_flight + 2,
+                                   OST_MAXREQSIZE,
+                                   ptlrpc_add_rqs_to_pool);
+
+       CFS_INIT_LIST_HEAD(&cli->cl_grant_shrink_list);
+       ns_register_cancel(obd->obd_namespace, osc_cancel_for_recovery);
+       RETURN(rc);
+
+out_ptlrpcd_work:
+       ptlrpcd_destroy_work(handler);
+out_client_setup:
+       client_obd_cleanup(obd);
+out_ptlrpcd:
+       ptlrpcd_decref();
+       RETURN(rc);
 }
 
 static int osc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
@@ -4417,29 +3508,30 @@ static int osc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
                 CDEBUG(D_HA, "Deactivating import %s\n", obd->obd_name);
                 /* ptlrpc_abort_inflight to stop an mds_lov_synchronize */
                 ptlrpc_deactivate_import(imp);
-                cfs_spin_lock(&imp->imp_lock);
-                imp->imp_pingable = 0;
-                cfs_spin_unlock(&imp->imp_lock);
+               spin_lock(&imp->imp_lock);
+               imp->imp_pingable = 0;
+               spin_unlock(&imp->imp_lock);
                 break;
         }
         case OBD_CLEANUP_EXPORTS: {
-                /* If we set up but never connected, the
-                   client import will not have been cleaned. */
-                if (obd->u.cli.cl_import) {
-                        struct obd_import *imp;
-                        cfs_down_write(&obd->u.cli.cl_sem);
-                        imp = obd->u.cli.cl_import;
-                        CDEBUG(D_CONFIG, "%s: client import never connected\n",
-                               obd->obd_name);
-                        ptlrpc_invalidate_import(imp);
-                        if (imp->imp_rq_pool) {
-                                ptlrpc_free_rq_pool(imp->imp_rq_pool);
-                                imp->imp_rq_pool = NULL;
-                        }
-                        class_destroy_import(imp);
-                        cfs_up_write(&obd->u.cli.cl_sem);
-                        obd->u.cli.cl_import = NULL;
+                struct client_obd *cli = &obd->u.cli;
+                /* LU-464
+                 * for echo client, export may be on zombie list, wait for
+                 * zombie thread to cull it, because cli.cl_import will be
+                 * cleared in client_disconnect_export():
+                 *   class_export_destroy() -> obd_cleanup() ->
+                 *   echo_device_free() -> echo_client_cleanup() ->
+                 *   obd_disconnect() -> osc_disconnect() ->
+                 *   client_disconnect_export()
+                 */
+                obd_zombie_barrier();
+                if (cli->cl_writeback_work) {
+                        ptlrpcd_destroy_work(cli->cl_writeback_work);
+                        cli->cl_writeback_work = NULL;
                 }
+                obd_cleanup_client_import(obd);
+                ptlrpc_lprocfs_unregister_obd(obd);
+                lprocfs_obd_cleanup(obd);
                 rc = obd_llog_finish(obd, 0);
                 if (rc != 0)
                         CERROR("failed to cleanup llogging subsystems\n");
@@ -4451,14 +3543,24 @@ static int osc_precleanup(struct obd_device *obd, enum obd_cleanup_stage stage)
 
 int osc_cleanup(struct obd_device *obd)
 {
-        int rc;
+       struct client_obd *cli = &obd->u.cli;
+       int rc;
 
-        ENTRY;
-        ptlrpc_lprocfs_unregister_obd(obd);
-        lprocfs_obd_cleanup(obd);
+       ENTRY;
+
+       /* lru cleanup */
+       if (cli->cl_cache != NULL) {
+               LASSERT(cfs_atomic_read(&cli->cl_cache->ccc_users) > 0);
+               spin_lock(&cli->cl_cache->ccc_lru_lock);
+               cfs_list_del_init(&cli->cl_lru_osc);
+               spin_unlock(&cli->cl_cache->ccc_lru_lock);
+               cli->cl_lru_left = NULL;
+               cfs_atomic_dec(&cli->cl_cache->ccc_users);
+               cli->cl_cache = NULL;
+       }
 
         /* free memory of osc quota cache */
-        lquota_cleanup(quota_interface, obd);
+        osc_quota_cleanup(obd);
 
         rc = client_obd_cleanup(obd);
 
@@ -4504,9 +3606,7 @@ struct obd_ops osc_obd_ops = {
         .o_statfs_async         = osc_statfs_async,
         .o_packmd               = osc_packmd,
         .o_unpackmd             = osc_unpackmd,
-        .o_precreate            = osc_precreate,
         .o_create               = osc_create,
-        .o_create_async         = osc_create_async,
         .o_destroy              = osc_destroy,
         .o_getattr              = osc_getattr,
         .o_getattr_async        = osc_getattr_async,
@@ -4527,11 +3627,13 @@ struct obd_ops osc_obd_ops = {
         .o_llog_init            = osc_llog_init,
         .o_llog_finish          = osc_llog_finish,
         .o_process_config       = osc_process_config,
+        .o_quotactl             = osc_quotactl,
+        .o_quotacheck           = osc_quotacheck,
 };
 
 extern struct lu_kmem_descr osc_caches[];
-extern cfs_spinlock_t       osc_ast_guard;
-extern cfs_lock_class_key_t osc_ast_guard_class;
+extern spinlock_t osc_ast_guard;
+extern struct lock_class_key osc_ast_guard_class;
 
 int __init osc_init(void)
 {
@@ -4542,49 +3644,30 @@ int __init osc_init(void)
         /* print an address of _any_ initialized kernel symbol from this
          * module, to allow debugging with gdb that doesn't support data
          * symbols from modules.*/
-        CDEBUG(D_CONSOLE, "Lustre OSC module (%p).\n", &osc_caches);
+        CDEBUG(D_INFO, "Lustre OSC module (%p).\n", &osc_caches);
 
         rc = lu_kmem_init(osc_caches);
 
         lprocfs_osc_init_vars(&lvars);
 
-        cfs_request_module("lquota");
-        quota_interface = PORTAL_SYMBOL_GET(osc_quota_interface);
-        lquota_init(quota_interface);
-        init_obd_quota_ops(quota_interface, &osc_obd_ops);
-
         rc = class_register_type(&osc_obd_ops, NULL, lvars.module_vars,
                                  LUSTRE_OSC_NAME, &osc_device_type);
         if (rc) {
-                if (quota_interface)
-                        PORTAL_SYMBOL_PUT(osc_quota_interface);
                 lu_kmem_fini(osc_caches);
                 RETURN(rc);
         }
 
-        cfs_spin_lock_init(&osc_ast_guard);
-        cfs_lockdep_set_class(&osc_ast_guard, &osc_ast_guard_class);
+       spin_lock_init(&osc_ast_guard);
+       lockdep_set_class(&osc_ast_guard, &osc_ast_guard_class);
 
-        osc_mds_ost_orig_logops = llog_lvfs_ops;
-        osc_mds_ost_orig_logops.lop_setup = llog_obd_origin_setup;
-        osc_mds_ost_orig_logops.lop_cleanup = llog_obd_origin_cleanup;
-        osc_mds_ost_orig_logops.lop_add = llog_obd_origin_add;
-        osc_mds_ost_orig_logops.lop_connect = llog_origin_connect;
-
-        RETURN(rc);
+       RETURN(rc);
 }
 
 #ifdef __KERNEL__
 static void /*__exit*/ osc_exit(void)
 {
-        lu_device_type_fini(&osc_device_type);
-
-        lquota_exit(quota_interface);
-        if (quota_interface)
-                PORTAL_SYMBOL_PUT(osc_quota_interface);
-
-        class_unregister_type(LUSTRE_OSC_NAME);
-        lu_kmem_fini(osc_caches);
+       class_unregister_type(LUSTRE_OSC_NAME);
+       lu_kmem_fini(osc_caches);
 }
 
 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");