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LU-2430 mdt: Add global rename lock.
[fs/lustre-release.git] / lustre / mdt / mdt_handler.c
index b5e0d74..0fa9e83 100644 (file)
 /* lu2dt_dev() */
 #include <dt_object.h>
 #include <lustre_mds.h>
-#include <lustre_mdt.h>
 #include <lustre_log.h>
 #include "mdt_internal.h"
 #include <lustre_acl.h>
 #include <lustre_param.h>
 #include <lustre_quota.h>
+#include <lustre_lfsck.h>
 
 mdl_mode_t mdt_mdl_lock_modes[] = {
         [LCK_MINMODE] = MDL_MINMODE,
@@ -91,16 +91,19 @@ ldlm_mode_t mdt_dlm_lock_modes[] = {
         [MDL_GROUP]   = LCK_GROUP
 };
 
-
 static struct mdt_device *mdt_dev(struct lu_device *d);
 static int mdt_unpack_req_pack_rep(struct mdt_thread_info *info, __u32 flags);
-static int mdt_fid2path(const struct lu_env *env, struct mdt_device *mdt,
-                        struct getinfo_fid2path *fp);
 
 static const struct lu_object_operations mdt_obj_ops;
 
 /* Slab for MDT object allocation */
-static cfs_mem_cache_t *mdt_object_kmem;
+static struct kmem_cache *mdt_object_kmem;
+
+/* For HSM restore handles */
+struct kmem_cache *mdt_hsm_cdt_kmem;
+
+/* For HSM request handles */
+struct kmem_cache *mdt_hsm_car_kmem;
 
 static struct lu_kmem_descr mdt_caches[] = {
        {
@@ -109,6 +112,16 @@ static struct lu_kmem_descr mdt_caches[] = {
                .ckd_size  = sizeof(struct mdt_object)
        },
        {
+               .ckd_cache      = &mdt_hsm_cdt_kmem,
+               .ckd_name       = "mdt_cdt_restore_handle",
+               .ckd_size       = sizeof(struct cdt_restore_handle)
+       },
+       {
+               .ckd_cache      = &mdt_hsm_car_kmem,
+               .ckd_name       = "mdt_cdt_agent_req",
+               .ckd_size       = sizeof(struct cdt_agent_req)
+       },
+       {
                .ckd_cache = NULL
        }
 };
@@ -121,43 +134,57 @@ int mdt_get_disposition(struct ldlm_reply *rep, int flag)
 }
 
 void mdt_clear_disposition(struct mdt_thread_info *info,
-                           struct ldlm_reply *rep, int flag)
+                          struct ldlm_reply *rep, int flag)
 {
-        if (info)
-                info->mti_opdata &= ~flag;
-        if (rep)
-                rep->lock_policy_res1 &= ~flag;
+       if (info) {
+               info->mti_opdata &= ~flag;
+               tgt_opdata_clear(info->mti_env, flag);
+       }
+       if (rep)
+               rep->lock_policy_res1 &= ~flag;
 }
 
 void mdt_set_disposition(struct mdt_thread_info *info,
-                         struct ldlm_reply *rep, int flag)
+                        struct ldlm_reply *rep, int flag)
 {
-        if (info)
-                info->mti_opdata |= flag;
-        if (rep)
-                rep->lock_policy_res1 |= flag;
+       if (info) {
+               info->mti_opdata |= flag;
+               tgt_opdata_set(info->mti_env, flag);
+       }
+       if (rep)
+               rep->lock_policy_res1 |= flag;
 }
 
 void mdt_lock_reg_init(struct mdt_lock_handle *lh, ldlm_mode_t lm)
 {
         lh->mlh_pdo_hash = 0;
         lh->mlh_reg_mode = lm;
+       lh->mlh_rreg_mode = lm;
         lh->mlh_type = MDT_REG_LOCK;
 }
 
-void mdt_lock_pdo_init(struct mdt_lock_handle *lh, ldlm_mode_t lm,
-                       const char *name, int namelen)
-{
-        lh->mlh_reg_mode = lm;
-        lh->mlh_type = MDT_PDO_LOCK;
-
-        if (name != NULL && (name[0] != '\0')) {
-                LASSERT(namelen > 0);
-                lh->mlh_pdo_hash = full_name_hash(name, namelen);
-        } else {
-                LASSERT(namelen == 0);
-                lh->mlh_pdo_hash = 0ull;
-        }
+void mdt_lock_pdo_init(struct mdt_lock_handle *lh, ldlm_mode_t lock_mode,
+                      const struct lu_name *lname)
+{
+       lh->mlh_reg_mode = lock_mode;
+       lh->mlh_rreg_mode = lock_mode;
+       lh->mlh_type = MDT_PDO_LOCK;
+
+       if (lu_name_is_valid(lname)) {
+               lh->mlh_pdo_hash = full_name_hash(lname->ln_name,
+                                                 lname->ln_namelen);
+               /* XXX Workaround for LU-2856
+                *
+                * Zero is a valid return value of full_name_hash, but
+                * several users of mlh_pdo_hash assume a non-zero
+                * hash value. We therefore map zero onto an
+                * arbitrary, but consistent value (1) to avoid
+                * problems further down the road. */
+               if (unlikely(lh->mlh_pdo_hash == 0))
+                       lh->mlh_pdo_hash = 1;
+       } else {
+               lh->mlh_pdo_hash = 0;
+       }
 }
 
 static void mdt_lock_pdo_mode(struct mdt_thread_info *info, struct mdt_object *o,
@@ -235,37 +262,34 @@ static void mdt_lock_pdo_mode(struct mdt_thread_info *info, struct mdt_object *o
         EXIT;
 }
 
-int mdt_getstatus(struct mdt_thread_info *info)
+int mdt_getstatus(struct tgt_session_info *tsi)
 {
-        struct mdt_device *mdt  = info->mti_mdt;
-        struct md_device  *next = mdt->mdt_child;
-        struct mdt_body   *repbody;
-        int                rc;
-
-        ENTRY;
+       struct mdt_thread_info  *info = tsi2mdt_info(tsi);
+       struct mdt_device       *mdt = info->mti_mdt;
+       struct mdt_body         *repbody;
+       int                      rc;
 
-        rc = mdt_check_ucred(info);
-        if (rc)
-                RETURN(err_serious(rc));
+       ENTRY;
 
-        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_GETSTATUS_PACK))
-                RETURN(err_serious(-ENOMEM));
+       rc = mdt_check_ucred(info);
+       if (rc)
+               GOTO(out, rc = err_serious(rc));
 
-        repbody = req_capsule_server_get(info->mti_pill, &RMF_MDT_BODY);
-        rc = next->md_ops->mdo_root_get(info->mti_env, next, &repbody->fid1);
-        if (rc != 0)
-                RETURN(rc);
+       if (OBD_FAIL_CHECK(OBD_FAIL_MDS_GETSTATUS_PACK))
+               GOTO(out, rc = err_serious(-ENOMEM));
 
-        repbody->valid |= OBD_MD_FLID;
+       repbody = req_capsule_server_get(info->mti_pill, &RMF_MDT_BODY);
+       repbody->fid1 = mdt->mdt_md_root_fid;
+       repbody->valid |= OBD_MD_FLID;
 
-        if (mdt->mdt_opts.mo_mds_capa &&
-            info->mti_exp->exp_connect_flags & OBD_CONNECT_MDS_CAPA) {
-                struct mdt_object  *root;
-                struct lustre_capa *capa;
+       if (tsi->tsi_tgt->lut_mds_capa &&
+           exp_connect_flags(info->mti_exp) & OBD_CONNECT_MDS_CAPA) {
+               struct mdt_object       *root;
+               struct lustre_capa      *capa;
 
-                root = mdt_object_find(info->mti_env, mdt, &repbody->fid1);
-                if (IS_ERR(root))
-                        RETURN(PTR_ERR(root));
+               root = mdt_object_find(info->mti_env, mdt, &repbody->fid1);
+               if (IS_ERR(root))
+                       GOTO(out, rc = PTR_ERR(root));
 
                 capa = req_capsule_server_get(info->mti_pill, &RMF_CAPA1);
                 LASSERT(capa);
@@ -276,13 +300,16 @@ int mdt_getstatus(struct mdt_thread_info *info)
                 if (rc == 0)
                         repbody->valid |= OBD_MD_FLMDSCAPA;
         }
-
-        RETURN(rc);
+       EXIT;
+out:
+       mdt_thread_info_fini(info);
+       return rc;
 }
 
-int mdt_statfs(struct mdt_thread_info *info)
+int mdt_statfs(struct tgt_session_info *tsi)
 {
-       struct ptlrpc_request           *req = mdt_info_req(info);
+       struct ptlrpc_request           *req = tgt_ses_req(tsi);
+       struct mdt_thread_info          *info = tsi2mdt_info(tsi);
        struct md_device                *next = info->mti_mdt->mdt_child;
        struct ptlrpc_service_part      *svcpt;
        struct obd_statfs               *osfs;
@@ -290,23 +317,23 @@ int mdt_statfs(struct mdt_thread_info *info)
 
        ENTRY;
 
-       svcpt = info->mti_pill->rc_req->rq_rqbd->rqbd_svcpt;
+       svcpt = req->rq_rqbd->rqbd_svcpt;
 
        /* This will trigger a watchdog timeout */
        OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_STATFS_LCW_SLEEP,
                         (MDT_SERVICE_WATCHDOG_FACTOR *
                          at_get(&svcpt->scp_at_estimate)) + 1);
 
-        rc = mdt_check_ucred(info);
-        if (rc)
-                RETURN(err_serious(rc));
+       rc = mdt_check_ucred(info);
+       if (rc)
+               GOTO(out, rc = err_serious(rc));
 
        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_STATFS_PACK))
-               RETURN(err_serious(-ENOMEM));
+               GOTO(out, rc = err_serious(-ENOMEM));
 
        osfs = req_capsule_server_get(info->mti_pill, &RMF_OBD_STATFS);
        if (!osfs)
-               RETURN(-EPROTO);
+               GOTO(out, rc = -EPROTO);
 
        /** statfs information are cached in the mdt_device */
        if (cfs_time_before_64(info->mti_mdt->mdt_osfs_age,
@@ -314,7 +341,7 @@ int mdt_statfs(struct mdt_thread_info *info)
                /** statfs data is too old, get up-to-date one */
                rc = next->md_ops->mdo_statfs(info->mti_env, next, osfs);
                if (rc)
-                       RETURN(rc);
+                       GOTO(out, rc);
                spin_lock(&info->mti_mdt->mdt_osfs_lock);
                info->mti_mdt->mdt_osfs = *osfs;
                info->mti_mdt->mdt_osfs_age = cfs_time_current_64();
@@ -328,7 +355,8 @@ int mdt_statfs(struct mdt_thread_info *info)
 
        if (rc == 0)
                mdt_counter_incr(req, LPROC_MDT_STATFS);
-
+out:
+       mdt_thread_info_fini(info);
        RETURN(rc);
 }
 
@@ -393,7 +421,18 @@ void mdt_pack_attr2body(struct mdt_thread_info *info, struct mdt_body *b,
                 b->blocks = 0;
                 /* if no object is allocated on osts, the size on mds is valid. b=22272 */
                 b->valid |= OBD_MD_FLSIZE | OBD_MD_FLBLOCKS;
-        }
+       } else if ((ma->ma_valid & MA_LOV) && ma->ma_lmm != NULL &&
+                  ma->ma_lmm->lmm_pattern & LOV_PATTERN_F_RELEASED) {
+               /* A released file stores its size on MDS. */
+               /* But return 1 block for released file, unless tools like tar
+                * will consider it fully sparse. (LU-3864)
+                */
+               if (unlikely(b->size == 0))
+                       b->blocks = 0;
+               else
+                       b->blocks = 1;
+               b->valid |= OBD_MD_FLSIZE | OBD_MD_FLBLOCKS;
+       }
 
         if (fid) {
                 b->fid1 = *fid;
@@ -405,7 +444,7 @@ void mdt_pack_attr2body(struct mdt_thread_info *info, struct mdt_body *b,
         if (info)
                 mdt_body_reverse_idmap(info, b);
 
-        if (b->valid & OBD_MD_FLSIZE)
+       if (fid != NULL && (b->valid & OBD_MD_FLSIZE))
                 CDEBUG(D_VFSTRACE, DFID": returning size %llu\n",
                        PFID(fid), (unsigned long long)b->size);
 }
@@ -426,9 +465,9 @@ void mdt_client_compatibility(struct mdt_thread_info *info)
         struct lu_attr        *la = &ma->ma_attr;
         ENTRY;
 
-        if (exp->exp_connect_flags & OBD_CONNECT_LAYOUTLOCK)
-                /* the client can deal with 16-bit lmm_stripe_count */
-                RETURN_EXIT;
+       if (exp_connect_layout(exp))
+               /* the client can deal with 16-bit lmm_stripe_count */
+               RETURN_EXIT;
 
         body = req_capsule_server_get(info->mti_pill, &RMF_MDT_BODY);
 
@@ -443,7 +482,7 @@ void mdt_client_compatibility(struct mdt_thread_info *info)
 }
 
 static int mdt_big_xattr_get(struct mdt_thread_info *info, struct mdt_object *o,
-                            char *name)
+                            const char *name)
 {
        const struct lu_env *env = info->mti_env;
        int rc;
@@ -481,30 +520,66 @@ static int mdt_big_xattr_get(struct mdt_thread_info *info, struct mdt_object *o,
        RETURN(rc);
 }
 
-int mdt_attr_get_lov(struct mdt_thread_info *info,
-                    struct mdt_object *o, struct md_attr *ma)
+int mdt_stripe_get(struct mdt_thread_info *info, struct mdt_object *o,
+                  struct md_attr *ma, const char *name)
 {
        struct md_object *next = mdt_object_child(o);
        struct lu_buf    *buf = &info->mti_buf;
        int rc;
 
-       buf->lb_buf = ma->ma_lmm;
-       buf->lb_len = ma->ma_lmm_size;
-       rc = mo_xattr_get(info->mti_env, next, buf, XATTR_NAME_LOV);
+       if (strcmp(name, XATTR_NAME_LOV) == 0) {
+               buf->lb_buf = ma->ma_lmm;
+               buf->lb_len = ma->ma_lmm_size;
+               LASSERT(!(ma->ma_valid & MA_LOV));
+       } else if (strcmp(name, XATTR_NAME_LMV) == 0) {
+               buf->lb_buf = ma->ma_lmv;
+               buf->lb_len = ma->ma_lmv_size;
+               LASSERT(!(ma->ma_valid & MA_LMV));
+       } else if (strcmp(name, XATTR_NAME_DEFAULT_LMV) == 0) {
+               buf->lb_buf = ma->ma_lmv;
+               buf->lb_len = ma->ma_lmv_size;
+               LASSERT(!(ma->ma_valid & MA_LMV_DEF));
+       } else {
+               return -EINVAL;
+       }
+
+       rc = mo_xattr_get(info->mti_env, next, buf, name);
        if (rc > 0) {
-               ma->ma_lmm_size = rc;
-               ma->ma_valid |= MA_LOV;
+               if (strcmp(name, XATTR_NAME_LOV) == 0) {
+                       ma->ma_lmm_size = rc;
+                       ma->ma_valid |= MA_LOV;
+               } else if (strcmp(name, XATTR_NAME_LMV) == 0) {
+                       ma->ma_lmv_size = rc;
+                       ma->ma_valid |= MA_LMV;
+               } else if (strcmp(name, XATTR_NAME_DEFAULT_LMV) == 0) {
+                       ma->ma_lmv_size = rc;
+                       ma->ma_valid |= MA_LMV_DEF;
+               }
+
                rc = 0;
        } else if (rc == -ENODATA) {
                /* no LOV EA */
                rc = 0;
        } else if (rc == -ERANGE) {
-               rc = mdt_big_xattr_get(info, o, XATTR_NAME_LOV);
+               /* Default LMV has fixed size, so it must be able to fit
+                * in the original buffer */
+               if (strcmp(name, XATTR_NAME_DEFAULT_LMV) == 0)
+                       return rc;
+               rc = mdt_big_xattr_get(info, o, name);
                if (rc > 0) {
                        info->mti_big_lmm_used = 1;
-                       ma->ma_valid |= MA_LOV;
-                       ma->ma_lmm = info->mti_big_lmm;
-                       ma->ma_lmm_size = rc;
+                       if (!strcmp(name, XATTR_NAME_LOV)) {
+                               ma->ma_valid |= MA_LOV;
+                               ma->ma_lmm = info->mti_big_lmm;
+                               ma->ma_lmm_size = rc;
+                       } else if (!strcmp(name, XATTR_NAME_LMV)) {
+                               ma->ma_valid |= MA_LMV;
+                               ma->ma_lmv = info->mti_big_lmm;
+                               ma->ma_lmv_size = rc;
+                       } else {
+                               return -EINVAL;
+                       }
+
                        /* update mdt_max_mdsize so all clients
                         * will be aware about that */
                        if (info->mti_mdt->mdt_max_mdsize < rc)
@@ -593,23 +668,21 @@ int mdt_attr_get_complex(struct mdt_thread_info *info,
        }
 
        if (need & MA_LOV && (S_ISREG(mode) || S_ISDIR(mode))) {
-               rc = mdt_attr_get_lov(info, o, ma);
+               rc = mdt_stripe_get(info, o, ma, XATTR_NAME_LOV);
                if (rc)
                        GOTO(out, rc);
        }
 
        if (need & MA_LMV && S_ISDIR(mode)) {
-               buf->lb_buf = ma->ma_lmv;
-               buf->lb_len = ma->ma_lmv_size;
-               rc2 = mo_xattr_get(env, next, buf, XATTR_NAME_LMV);
-               if (rc2 > 0) {
-                       ma->ma_lmv_size = rc2;
-                       ma->ma_valid |= MA_LMV;
-               } else if (rc2 == -ENODATA) {
-                       /* no LMV EA */
-                       ma->ma_lmv_size = 0;
-               } else
-                       GOTO(out, rc = rc2);
+               rc = mdt_stripe_get(info, o, ma, XATTR_NAME_LMV);
+               if (rc != 0)
+                       GOTO(out, rc);
+       }
+
+       if (need & MA_LMV_DEF && S_ISDIR(mode)) {
+               rc = mdt_stripe_get(info, o, ma, XATTR_NAME_DEFAULT_LMV);
+               if (rc != 0)
+                       GOTO(out, rc);
        }
 
        if (need & MA_SOM && S_ISREG(mode)) {
@@ -683,32 +756,50 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
 
         ma->ma_valid = 0;
 
-        rc = mdt_object_exists(o);
-        if (rc < 0) {
-                /* This object is located on remote node.*/
-                repbody->fid1 = *mdt_object_fid(o);
-                repbody->valid = OBD_MD_FLID | OBD_MD_MDS;
-                GOTO(out, rc = 0);
-        }
+       if (mdt_object_remote(o)) {
+               /* This object is located on remote node.*/
+               /* Return -EIO for old client */
+               if (!mdt_is_dne_client(req->rq_export))
+                       GOTO(out, rc = -EIO);
+
+               repbody->fid1 = *mdt_object_fid(o);
+               repbody->valid = OBD_MD_FLID | OBD_MD_MDS;
+               GOTO(out, rc = 0);
+       }
 
        buffer->lb_len = reqbody->eadatasize;
-       if (buffer->lb_len > 0)
+       if (buffer->lb_len > 0) {
                buffer->lb_buf = req_capsule_server_get(pill, &RMF_MDT_MD);
-       else
+               if (buffer->lb_buf == NULL)
+                       GOTO(out, rc = -EPROTO);
+       } else {
                buffer->lb_buf = NULL;
+               ma_need &= ~(MA_LOV | MA_LMV);
+               CDEBUG(D_INFO, "%s: RPC from %s: does not need LOVEA.\n",
+                      mdt_obd_name(info->mti_mdt),
+                      req->rq_export->exp_client_uuid.uuid);
+       }
 
-        /* If it is dir object and client require MEA, then we got MEA */
-        if (S_ISDIR(lu_object_attr(&next->mo_lu)) &&
-            reqbody->valid & OBD_MD_MEA) {
-                /* Assumption: MDT_MD size is enough for lmv size. */
-                ma->ma_lmv = buffer->lb_buf;
-                ma->ma_lmv_size = buffer->lb_len;
-                ma->ma_need = MA_LMV | MA_INODE;
-        } else {
-                ma->ma_lmm = buffer->lb_buf;
-                ma->ma_lmm_size = buffer->lb_len;
-               ma->ma_need = MA_LOV | MA_INODE | MA_HSM;
-        }
+       /* If it is dir object and client require MEA, then we got MEA */
+       if (S_ISDIR(lu_object_attr(&next->mo_lu)) &&
+           (reqbody->valid & (OBD_MD_MEA | OBD_MD_DEFAULT_MEA))) {
+               /* Assumption: MDT_MD size is enough for lmv size. */
+               ma->ma_lmv = buffer->lb_buf;
+               ma->ma_lmv_size = buffer->lb_len;
+               ma->ma_need = MA_INODE;
+               if (ma->ma_lmv_size > 0) {
+                       if (reqbody->valid & OBD_MD_MEA)
+                               ma->ma_need |= MA_LMV;
+                       else if (reqbody->valid & OBD_MD_DEFAULT_MEA)
+                               ma->ma_need |= MA_LMV_DEF;
+               }
+       } else {
+               ma->ma_lmm = buffer->lb_buf;
+               ma->ma_lmm_size = buffer->lb_len;
+               ma->ma_need = MA_INODE | MA_HSM;
+               if (ma->ma_lmm_size > 0)
+                       ma->ma_need |= MA_LOV;
+       }
 
         if (S_ISDIR(lu_object_attr(&next->mo_lu)) &&
             reqbody->valid & OBD_MD_FLDIREA  &&
@@ -721,18 +812,26 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
                 ma->ma_som = &info->mti_u.som.data;
 
        rc = mdt_attr_get_complex(info, o, ma);
-        if (unlikely(rc)) {
-                CERROR("getattr error for "DFID": %d\n",
-                        PFID(mdt_object_fid(o)), rc);
-                RETURN(rc);
-        }
+       if (unlikely(rc)) {
+               CERROR("%s: getattr error for "DFID": rc = %d\n",
+                      mdt_obd_name(info->mti_mdt),
+                      PFID(mdt_object_fid(o)), rc);
+               RETURN(rc);
+       }
+
+       /* if file is released, check if a restore is running */
+       if ((ma->ma_valid & MA_HSM) && (ma->ma_hsm.mh_flags & HS_RELEASED) &&
+           mdt_hsm_restore_is_running(info, mdt_object_fid(o))) {
+               repbody->t_state = MS_RESTORE;
+               repbody->valid |= OBD_MD_TSTATE;
+       }
 
        is_root = lu_fid_eq(mdt_object_fid(o), &info->mti_mdt->mdt_md_root_fid);
 
        /* the Lustre protocol supposes to return default striping
         * on the user-visible root if explicitly requested */
        if ((ma->ma_valid & MA_LOV) == 0 && S_ISDIR(la->la_mode) &&
-           (ma->ma_need & MA_LOV_DEF && is_root) && (ma->ma_need & MA_LOV)) {
+           (ma->ma_need & MA_LOV_DEF && is_root) && ma->ma_need & MA_LOV) {
                struct lu_fid      rootfid;
                struct mdt_object *root;
                struct mdt_device *mdt = info->mti_mdt;
@@ -743,11 +842,12 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
                root = mdt_object_find(env, mdt, &rootfid);
                if (IS_ERR(root))
                        RETURN(PTR_ERR(root));
-               rc = mdt_attr_get_lov(info, root, ma);
+               rc = mdt_stripe_get(info, root, ma, XATTR_NAME_LOV);
                mdt_object_put(info->mti_env, root);
                if (unlikely(rc)) {
-                       CERROR("getattr error for "DFID": %d\n",
-                                       PFID(mdt_object_fid(o)), rc);
+                       CERROR("%s: getattr error for "DFID": rc = %d\n",
+                              mdt_obd_name(info->mti_mdt),
+                              PFID(mdt_object_fid(o)), rc);
                        RETURN(rc);
                }
        }
@@ -767,23 +867,31 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
                         else
                                 repbody->valid |= OBD_MD_FLEASIZE;
                 }
-                if (ma->ma_valid & MA_LMV) {
-                        LASSERT(S_ISDIR(la->la_mode));
-                        repbody->eadatasize = ma->ma_lmv_size;
-                        repbody->valid |= (OBD_MD_FLDIREA|OBD_MD_MEA);
-                }
-        } else if (S_ISLNK(la->la_mode) &&
-                   reqbody->valid & OBD_MD_LINKNAME) {
-                buffer->lb_buf = ma->ma_lmm;
-                /* eadatasize from client includes NULL-terminator, so
-                 * there is no need to read it */
-                buffer->lb_len = reqbody->eadatasize - 1;
-                rc = mo_readlink(env, next, buffer);
-                if (unlikely(rc <= 0)) {
-                        CERROR("readlink failed: %d\n", rc);
-                        rc = -EFAULT;
-                } else {
-                       int print_limit = min_t(int, CFS_PAGE_SIZE - 128, rc);
+               if (ma->ma_valid & MA_LMV) {
+                       LASSERT(S_ISDIR(la->la_mode));
+                       mdt_dump_lmv(D_INFO, ma->ma_lmv);
+                       repbody->eadatasize = ma->ma_lmv_size;
+                       repbody->valid |= (OBD_MD_FLDIREA|OBD_MD_MEA);
+               }
+               if (ma->ma_valid & MA_LMV_DEF) {
+                       LASSERT(S_ISDIR(la->la_mode));
+                       repbody->eadatasize = ma->ma_lmv_size;
+                       repbody->valid |= (OBD_MD_FLDIREA|OBD_MD_DEFAULT_MEA);
+               }
+       } else if (S_ISLNK(la->la_mode) &&
+                  reqbody->valid & OBD_MD_LINKNAME) {
+               buffer->lb_buf = ma->ma_lmm;
+               /* eadatasize from client includes NULL-terminator, so
+                * there is no need to read it */
+               buffer->lb_len = reqbody->eadatasize - 1;
+               rc = mo_readlink(env, next, buffer);
+               if (unlikely(rc <= 0)) {
+                       CERROR("%s: readlink failed for "DFID": rc = %d\n",
+                              mdt_obd_name(info->mti_mdt),
+                              PFID(mdt_object_fid(o)), rc);
+                       rc = -EFAULT;
+               } else {
+                       int print_limit = min_t(int, PAGE_CACHE_SIZE - 128, rc);
 
                        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_READLINK_EPROTO))
                                rc -= 2;
@@ -792,8 +900,11 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
                         * because client expects that */
                        repbody->eadatasize = rc + 1;
                        if (repbody->eadatasize != reqbody->eadatasize)
-                               CERROR("Read shorter symlink %d, expected %d\n",
-                                      rc, reqbody->eadatasize - 1);
+                               CDEBUG(D_INODE, "%s: Read shorter symlink %d "
+                                      "on "DFID ", expected %d\n",
+                                      mdt_obd_name(info->mti_mdt),
+                                      rc, PFID(mdt_object_fid(o)),
+                                      reqbody->eadatasize - 1);
                        /* NULL terminate */
                        ((char *)ma->ma_lmm)[rc] = 0;
 
@@ -832,8 +943,8 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
                 }
         }
 #ifdef CONFIG_FS_POSIX_ACL
-        else if ((req->rq_export->exp_connect_flags & OBD_CONNECT_ACL) &&
-                 (reqbody->valid & OBD_MD_FLACL)) {
+       else if ((exp_connect_flags(req->rq_export) & OBD_CONNECT_ACL) &&
+                (reqbody->valid & OBD_MD_FLACL)) {
                 buffer->lb_buf = req_capsule_server_get(pill, &RMF_ACL);
                 buffer->lb_len = req_capsule_get_size(pill,
                                                       &RMF_ACL, RCL_SERVER);
@@ -847,9 +958,12 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
                                         rc = 0;
                                 } else if (rc == -EOPNOTSUPP) {
                                         rc = 0;
-                                } else {
-                                        CERROR("got acl size: %d\n", rc);
-                                }
+                               } else {
+                                       CERROR("%s: unable to read "DFID
+                                              " ACL: rc = %d\n",
+                                              mdt_obd_name(info->mti_mdt),
+                                              PFID(mdt_object_fid(o)), rc);
+                               }
                         } else {
                                 repbody->aclsize = rc;
                                 repbody->valid |= OBD_MD_FLACL;
@@ -859,9 +973,9 @@ static int mdt_getattr_internal(struct mdt_thread_info *info,
         }
 #endif
 
-        if (reqbody->valid & OBD_MD_FLMDSCAPA &&
-            info->mti_mdt->mdt_opts.mo_mds_capa &&
-            info->mti_exp->exp_connect_flags & OBD_CONNECT_MDS_CAPA) {
+       if (reqbody->valid & OBD_MD_FLMDSCAPA &&
+           info->mti_mdt->mdt_lut.lut_mds_capa &&
+           exp_connect_flags(info->mti_exp) & OBD_CONNECT_MDS_CAPA) {
                 struct lustre_capa *capa;
 
                 capa = req_capsule_server_get(pill, &RMF_CAPA1);
@@ -892,9 +1006,9 @@ static int mdt_renew_capa(struct mdt_thread_info *info)
          * return directly, client will find body->valid OBD_MD_FLOSSCAPA
          * flag not set.
          */
-        if (!obj || !info->mti_mdt->mdt_opts.mo_oss_capa ||
-            !(info->mti_exp->exp_connect_flags & OBD_CONNECT_OSS_CAPA))
-                RETURN(0);
+       if (!obj || !info->mti_mdt->mdt_lut.lut_oss_capa ||
+           !(exp_connect_flags(info->mti_exp) & OBD_CONNECT_OSS_CAPA))
+               RETURN(0);
 
         body = req_capsule_server_get(info->mti_pill, &RMF_MDT_BODY);
         LASSERT(body != NULL);
@@ -912,8 +1026,9 @@ static int mdt_renew_capa(struct mdt_thread_info *info)
         RETURN(rc);
 }
 
-int mdt_getattr(struct mdt_thread_info *info)
+int mdt_getattr(struct tgt_session_info *tsi)
 {
+       struct mdt_thread_info  *info = tsi2mdt_info(tsi);
         struct mdt_object       *obj = info->mti_object;
         struct req_capsule      *pill = info->mti_pill;
         struct mdt_body         *reqbody;
@@ -934,19 +1049,19 @@ int mdt_getattr(struct mdt_thread_info *info)
         }
 
         LASSERT(obj != NULL);
-        LASSERT(lu_object_assert_exists(&obj->mot_obj.mo_lu));
+       LASSERT(lu_object_assert_exists(&obj->mot_obj));
 
-        mode = lu_object_attr(&obj->mot_obj.mo_lu);
+       mode = lu_object_attr(&obj->mot_obj);
 
-        /* old clients may not report needed easize, use max value then */
-        req_capsule_set_size(pill, &RMF_MDT_MD, RCL_SERVER,
-                             reqbody->eadatasize == 0 ?
-                             info->mti_mdt->mdt_max_mdsize :
-                             reqbody->eadatasize);
+       /* old clients may not report needed easize, use max value then */
+       req_capsule_set_size(pill, &RMF_MDT_MD, RCL_SERVER,
+                            reqbody->eadatasize == 0 ?
+                            info->mti_mdt->mdt_max_mdsize :
+                            reqbody->eadatasize);
 
-        rc = req_capsule_server_pack(pill);
-        if (unlikely(rc != 0))
-                RETURN(err_serious(rc));
+       rc = req_capsule_server_pack(pill);
+       if (unlikely(rc != 0))
+               GOTO(out, rc = err_serious(rc));
 
         repbody = req_capsule_server_get(pill, &RMF_MDT_BODY);
         LASSERT(repbody != NULL);
@@ -976,11 +1091,14 @@ out_shrink:
         rc2 = mdt_fix_reply(info);
         if (rc == 0)
                 rc = rc2;
-        return rc;
+out:
+       mdt_thread_info_fini(info);
+       return rc;
 }
 
-int mdt_is_subdir(struct mdt_thread_info *info)
+int mdt_is_subdir(struct tgt_session_info *tsi)
 {
+       struct mdt_thread_info  *info = tsi2mdt_info(tsi);
         struct mdt_object     *o = info->mti_object;
         struct req_capsule    *pill = info->mti_pill;
         const struct mdt_body *body = info->mti_body;
@@ -992,18 +1110,112 @@ int mdt_is_subdir(struct mdt_thread_info *info)
 
         repbody = req_capsule_server_get(pill, &RMF_MDT_BODY);
 
-        /*
-         * We save last checked parent fid to @repbody->fid1 for remote
-         * directory case.
-         */
-        LASSERT(fid_is_sane(&body->fid2));
-        LASSERT(mdt_object_exists(o) > 0);
-        rc = mdo_is_subdir(info->mti_env, mdt_object_child(o),
-                           &body->fid2, &repbody->fid1);
-        if (rc == 0 || rc == -EREMOTE)
-                repbody->valid |= OBD_MD_FLID;
+       /*
+        * We save last checked parent fid to @repbody->fid1 for remote
+        * directory case.
+        */
+       LASSERT(fid_is_sane(&body->fid2));
+       LASSERT(mdt_object_exists(o) && !mdt_object_remote(o));
+       rc = mdo_is_subdir(info->mti_env, mdt_object_child(o),
+                          &body->fid2, &repbody->fid1);
+       if (rc == 0 || rc == -EREMOTE)
+               repbody->valid |= OBD_MD_FLID;
+
+       mdt_thread_info_fini(info);
+       RETURN(rc);
+}
 
-        RETURN(rc);
+int mdt_swap_layouts(struct tgt_session_info *tsi)
+{
+       struct mdt_thread_info  *info;
+       struct ptlrpc_request   *req = tgt_ses_req(tsi);
+       struct obd_export       *exp = req->rq_export;
+       struct mdt_object       *o1, *o2, *o;
+       struct mdt_lock_handle  *lh1, *lh2;
+       struct mdc_swap_layouts *msl;
+       int                      rc;
+       ENTRY;
+
+       /* client does not support layout lock, so layout swaping
+        * is disabled.
+        * FIXME: there is a problem for old clients which don't support
+        * layout lock yet. If those clients have already opened the file
+        * they won't be notified at all so that old layout may still be
+        * used to do IO. This can be fixed after file release is landed by
+        * doing exclusive open and taking full EX ibits lock. - Jinshan */
+       if (!exp_connect_layout(exp))
+               RETURN(-EOPNOTSUPP);
+
+       info = tsi2mdt_info(tsi);
+       if (req_capsule_get_size(info->mti_pill, &RMF_CAPA1, RCL_CLIENT))
+               mdt_set_capainfo(info, 0, &info->mti_body->fid1,
+                                req_capsule_client_get(info->mti_pill,
+                                                       &RMF_CAPA1));
+
+       if (req_capsule_get_size(info->mti_pill, &RMF_CAPA2, RCL_CLIENT))
+               mdt_set_capainfo(info, 1, &info->mti_body->fid2,
+                                req_capsule_client_get(info->mti_pill,
+                                                       &RMF_CAPA2));
+
+       o1 = info->mti_object;
+       o = o2 = mdt_object_find(info->mti_env, info->mti_mdt,
+                               &info->mti_body->fid2);
+       if (IS_ERR(o))
+               GOTO(out, rc = PTR_ERR(o));
+
+       if (mdt_object_remote(o) || !mdt_object_exists(o)) /* remote object */
+               GOTO(put, rc = -ENOENT);
+
+       rc = lu_fid_cmp(&info->mti_body->fid1, &info->mti_body->fid2);
+       if (unlikely(rc == 0)) /* same file, you kidding me? no-op. */
+               GOTO(put, rc);
+
+       if (rc < 0)
+               swap(o1, o2);
+
+       /* permission check. Make sure the calling process having permission
+        * to write both files. */
+       rc = mo_permission(info->mti_env, NULL, mdt_object_child(o1), NULL,
+                               MAY_WRITE);
+       if (rc < 0)
+               GOTO(put, rc);
+
+       rc = mo_permission(info->mti_env, NULL, mdt_object_child(o2), NULL,
+                               MAY_WRITE);
+       if (rc < 0)
+               GOTO(put, rc);
+
+       msl = req_capsule_client_get(info->mti_pill, &RMF_SWAP_LAYOUTS);
+       if (msl == NULL)
+               GOTO(put, rc = -EPROTO);
+
+       lh1 = &info->mti_lh[MDT_LH_NEW];
+       mdt_lock_reg_init(lh1, LCK_EX);
+       lh2 = &info->mti_lh[MDT_LH_OLD];
+       mdt_lock_reg_init(lh2, LCK_EX);
+
+       rc = mdt_object_lock(info, o1, lh1, MDS_INODELOCK_LAYOUT |
+                            MDS_INODELOCK_XATTR, MDT_LOCAL_LOCK);
+       if (rc < 0)
+               GOTO(put, rc);
+
+       rc = mdt_object_lock(info, o2, lh2, MDS_INODELOCK_LAYOUT |
+                            MDS_INODELOCK_XATTR, MDT_LOCAL_LOCK);
+       if (rc < 0)
+               GOTO(unlock1, rc);
+
+       rc = mo_swap_layouts(info->mti_env, mdt_object_child(o1),
+                            mdt_object_child(o2), msl->msl_flags);
+       GOTO(unlock2, rc);
+unlock2:
+       mdt_object_unlock(info, o2, lh2, rc);
+unlock1:
+       mdt_object_unlock(info, o1, lh1, rc);
+put:
+       mdt_object_put(info->mti_env, o);
+out:
+       mdt_thread_info_fini(info);
+       RETURN(rc);
 }
 
 static int mdt_raw_lookup(struct mdt_thread_info *info,
@@ -1064,8 +1276,6 @@ static int mdt_getattr_name_lock(struct mdt_thread_info *info,
         struct md_object       *next      = mdt_object_child(parent);
         struct lu_fid          *child_fid = &info->mti_tmp_fid1;
         struct lu_name         *lname     = NULL;
-        const char             *name      = NULL;
-        int                     namelen   = 0;
         struct mdt_lock_handle *lhp       = NULL;
         struct ldlm_lock       *lock;
         struct ldlm_res_id     *res_id;
@@ -1080,53 +1290,51 @@ static int mdt_getattr_name_lock(struct mdt_thread_info *info,
                      lustre_msg_get_flags(req->rq_reqmsg) & MSG_RESENT));
 
         LASSERT(parent != NULL);
-        name = req_capsule_client_get(info->mti_pill, &RMF_NAME);
-        if (name == NULL)
-                RETURN(err_serious(-EFAULT));
 
-        namelen = req_capsule_get_size(info->mti_pill, &RMF_NAME,
-                                       RCL_CLIENT) - 1;
-        if (!info->mti_cross_ref) {
-                /*
-                 * XXX: Check for "namelen == 0" is for getattr by fid
-                 * (OBD_CONNECT_ATTRFID), otherwise do not allow empty name,
-                 * that is the name must contain at least one character and
-                 * the terminating '\0'
-                 */
-                if (namelen == 0) {
-                        reqbody = req_capsule_client_get(info->mti_pill,
-                                                         &RMF_MDT_BODY);
-                        if (unlikely(reqbody == NULL))
-                                RETURN(err_serious(-EFAULT));
-
-                        if (unlikely(!fid_is_sane(&reqbody->fid2)))
-                                RETURN(err_serious(-EINVAL));
-
-                        name = NULL;
-                        CDEBUG(D_INODE, "getattr with lock for "DFID"/"DFID", "
-                               "ldlm_rep = %p\n",
-                               PFID(mdt_object_fid(parent)),
-                               PFID(&reqbody->fid2), ldlm_rep);
-                } else {
-                        lname = mdt_name(info->mti_env, (char *)name, namelen);
-                        CDEBUG(D_INODE, "getattr with lock for "DFID"/%s, "
-                               "ldlm_rep = %p\n", PFID(mdt_object_fid(parent)),
-                               name, ldlm_rep);
-                }
-        }
+       lname = &info->mti_name;
+       mdt_name_unpack(info->mti_pill, &RMF_NAME, lname, MNF_FIX_ANON);
+
+       if (!info->mti_cross_ref) {
+               /*
+                * XXX: Check for anonymous name is for getattr by fid
+                * (OBD_CONNECT_ATTRFID), otherwise do not allow empty name,
+                * that is the name must contain at least one character and
+                * the terminating '\0'.
+                */
+               if (!lu_name_is_valid(lname)) {
+                       reqbody = req_capsule_client_get(info->mti_pill,
+                                                        &RMF_MDT_BODY);
+                       if (unlikely(reqbody == NULL))
+                               RETURN(err_serious(-EFAULT));
+
+                       if (unlikely(!fid_is_sane(&reqbody->fid2)))
+                               RETURN(err_serious(-EINVAL));
+
+                       CDEBUG(D_INODE, "getattr with lock for "DFID"/"DFID", "
+                              "ldlm_rep = %p\n",
+                              PFID(mdt_object_fid(parent)),
+                              PFID(&reqbody->fid2), ldlm_rep);
+               } else {
+                       CDEBUG(D_INODE, "getattr with lock for "DFID"/"DNAME", "
+                              "ldlm_rep = %p\n", PFID(mdt_object_fid(parent)),
+                              PNAME(lname), ldlm_rep);
+               }
+       }
+
         mdt_set_disposition(info, ldlm_rep, DISP_LOOKUP_EXECD);
 
-       rc = mdt_object_exists(parent);
-       if (unlikely(rc == 0)) {
+       if (unlikely(!mdt_object_exists(parent)) && lu_name_is_valid(lname)) {
                LU_OBJECT_DEBUG(D_INODE, info->mti_env,
-                               &parent->mot_obj.mo_lu,
+                               &parent->mot_obj,
                                "Parent doesn't exist!\n");
                RETURN(-ESTALE);
        } else if (!info->mti_cross_ref) {
-               LASSERTF(rc > 0, "Parent "DFID" is on remote server\n",
+               LASSERTF(!mdt_object_remote(parent),
+                        "Parent "DFID" is on remote server\n",
                         PFID(mdt_object_fid(parent)));
        }
-        if (lname) {
+
+       if (lu_name_is_valid(lname)) {
                 rc = mdt_raw_lookup(info, parent, lname, ldlm_rep);
                 if (rc != 0) {
                         if (rc > 0)
@@ -1152,21 +1360,30 @@ static int mdt_getattr_name_lock(struct mdt_thread_info *info,
                         LDLM_LOCK_PUT(lock);
                         rc = 0;
                 } else {
-                        mdt_lock_handle_init(lhc);
-                        mdt_lock_reg_init(lhc, LCK_PR);
+                       mdt_lock_handle_init(lhc);
+                       mdt_lock_reg_init(lhc, LCK_PR);
 
-                        /*
-                         * Object's name is on another MDS, no lookup lock is
-                         * needed here but update is.
-                         */
-                        child_bits &= ~MDS_INODELOCK_LOOKUP;
-                        child_bits |= MDS_INODELOCK_UPDATE;
+                       /*
+                        * Object's name is on another MDS, no lookup or layout
+                        * lock is needed here but update lock is.
+                        */
+                       child_bits &= ~(MDS_INODELOCK_LOOKUP |
+                                       MDS_INODELOCK_LAYOUT);
+                       child_bits |= MDS_INODELOCK_PERM | MDS_INODELOCK_UPDATE;
 
-                        rc = mdt_object_lock(info, child, lhc, child_bits,
-                                             MDT_LOCAL_LOCK);
-                }
+                       rc = mdt_object_lock(info, child, lhc, child_bits,
+                                            MDT_LOCAL_LOCK);
+               }
                 if (rc == 0) {
                         /* Finally, we can get attr for child. */
+                       if (!mdt_object_exists(child)) {
+                               LU_OBJECT_DEBUG(D_INFO, info->mti_env,
+                                               &child->mot_obj,
+                                            "remote object doesn't exist.\n");
+                                mdt_object_unlock(info, child, lhc, 1);
+                               RETURN(-ENOENT);
+                       }
+
                         mdt_set_capainfo(info, 0, mdt_object_fid(child),
                                          BYPASS_CAPA);
                         rc = mdt_getattr_internal(info, child, 0);
@@ -1176,11 +1393,11 @@ static int mdt_getattr_name_lock(struct mdt_thread_info *info,
                 RETURN(rc);
         }
 
-        if (lname) {
-                /* step 1: lock parent only if parent is a directory */
-                if (S_ISDIR(lu_object_attr(&parent->mot_obj.mo_lu))) {
-                        lhp = &info->mti_lh[MDT_LH_PARENT];
-                        mdt_lock_pdo_init(lhp, LCK_PR, name, namelen);
+       if (lu_name_is_valid(lname)) {
+               /* step 1: lock parent only if parent is a directory */
+               if (S_ISDIR(lu_object_attr(&parent->mot_obj))) {
+                       lhp = &info->mti_lh[MDT_LH_PARENT];
+                       mdt_lock_pdo_init(lhp, LCK_PR, lname);
                         rc = mdt_object_lock(info, parent, lhp,
                                              MDS_INODELOCK_UPDATE,
                                              MDT_LOCAL_LOCK);
@@ -1205,41 +1422,50 @@ static int mdt_getattr_name_lock(struct mdt_thread_info *info,
                 mdt_set_disposition(info, ldlm_rep, DISP_LOOKUP_POS);
         }
 
-        /*
-         *step 3: find the child object by fid & lock it.
-         *        regardless if it is local or remote.
-         */
-        child = mdt_object_find(info->mti_env, info->mti_mdt, child_fid);
-
-        if (unlikely(IS_ERR(child)))
-                GOTO(out_parent, rc = PTR_ERR(child));
-        if (is_resent) {
-                /* Do not take lock for resent case. */
-                lock = ldlm_handle2lock(&lhc->mlh_reg_lh);
-                LASSERTF(lock != NULL, "Invalid lock handle "LPX64"\n",
-                         lhc->mlh_reg_lh.cookie);
-
-                res_id = &lock->l_resource->lr_name;
-                if (!fid_res_name_eq(mdt_object_fid(child),
-                                    &lock->l_resource->lr_name)) {
-                         LASSERTF(fid_res_name_eq(mdt_object_fid(parent),
-                                                 &lock->l_resource->lr_name),
-                                 "Lock res_id: %lu/%lu/%lu, Fid: "DFID".\n",
-                                 (unsigned long)res_id->name[0],
-                                 (unsigned long)res_id->name[1],
-                                 (unsigned long)res_id->name[2],
-                                 PFID(mdt_object_fid(parent)));
-                          CWARN("Although resent, but still not get child lock"
-                                "parent:"DFID" child:"DFID"\n",
-                                PFID(mdt_object_fid(parent)),
-                                PFID(mdt_object_fid(child)));
-                          lustre_msg_clear_flags(req->rq_reqmsg, MSG_RESENT);
-                          LDLM_LOCK_PUT(lock);
-                          GOTO(relock, 0);
-                }
-                LDLM_LOCK_PUT(lock);
-                rc = 0;
-        } else {
+       /*
+        *step 3: find the child object by fid & lock it.
+        *        regardless if it is local or remote.
+        *
+        *Note: LU-3240 (commit 762f2114d282a98ebfa4dbbeea9298a8088ad24e)
+        *      set parent dir fid the same as child fid in getattr by fid case
+        *      we should not lu_object_find() the object again, could lead
+        *      to hung if there is a concurrent unlink destroyed the object.
+        */
+       if (lu_fid_eq(mdt_object_fid(parent), child_fid)) {
+               mdt_object_get(info->mti_env, parent);
+               child = parent;
+       } else {
+               child = mdt_object_find(info->mti_env, info->mti_mdt,
+                                       child_fid);
+       }
+
+       if (unlikely(IS_ERR(child)))
+               GOTO(out_parent, rc = PTR_ERR(child));
+       if (is_resent) {
+               /* Do not take lock for resent case. */
+               lock = ldlm_handle2lock(&lhc->mlh_reg_lh);
+               LASSERTF(lock != NULL, "Invalid lock handle "LPX64"\n",
+                        lhc->mlh_reg_lh.cookie);
+
+               res_id = &lock->l_resource->lr_name;
+               if (!fid_res_name_eq(mdt_object_fid(child),
+                                    &lock->l_resource->lr_name)) {
+                       LASSERTF(fid_res_name_eq(mdt_object_fid(parent),
+                                                &lock->l_resource->lr_name),
+                                "Lock res_id: "DLDLMRES", fid: "DFID"\n",
+                                PLDLMRES(lock->l_resource),
+                                PFID(mdt_object_fid(parent)));
+                       CWARN("Although resent, but still not get child lock"
+                             "parent:"DFID" child:"DFID"\n",
+                             PFID(mdt_object_fid(parent)),
+                             PFID(mdt_object_fid(child)));
+                       lustre_msg_clear_flags(req->rq_reqmsg, MSG_RESENT);
+                       LDLM_LOCK_PUT(lock);
+                       GOTO(relock, 0);
+               }
+               LDLM_LOCK_PUT(lock);
+               rc = 0;
+       } else {
                bool try_layout = false;
 
 relock:
@@ -1247,14 +1473,15 @@ relock:
                 mdt_lock_handle_init(lhc);
                mdt_lock_reg_init(lhc, LCK_PR);
 
-                if (mdt_object_exists(child) == 0) {
-                        LU_OBJECT_DEBUG(D_INODE, info->mti_env,
-                                        &child->mot_obj.mo_lu,
-                                        "Object doesn't exist!\n");
-                        GOTO(out_child, rc = -ENOENT);
-                }
+               if (!mdt_object_exists(child)) {
+                       LU_OBJECT_DEBUG(D_INODE, info->mti_env,
+                                       &child->mot_obj,
+                                       "Object doesn't exist!\n");
+                       GOTO(out_child, rc = -ENOENT);
+               }
 
-                if (!(child_bits & MDS_INODELOCK_UPDATE)) {
+               if (!(child_bits & MDS_INODELOCK_UPDATE) &&
+                     mdt_object_exists(child) && !mdt_object_remote(child)) {
                         struct md_attr *ma = &info->mti_attr;
 
                         ma->ma_valid = 0;
@@ -1263,11 +1490,11 @@ relock:
                         if (unlikely(rc != 0))
                                 GOTO(out_child, rc);
 
-                        /* If the file has not been changed for some time, we
-                         * return not only a LOOKUP lock, but also an UPDATE
-                         * lock and this might save us RPC on later STAT. For
-                         * directories, it also let negative dentry starts
-                         * working for this dir. */
+                       /* If the file has not been changed for some time, we
+                        * return not only a LOOKUP lock, but also an UPDATE
+                        * lock and this might save us RPC on later STAT. For
+                        * directories, it also let negative dentry cache start
+                        * working for this dir. */
                         if (ma->ma_valid & MA_INODE &&
                             ma->ma_attr.la_valid & LA_CTIME &&
                             info->mti_mdt->mdt_namespace->ns_ctime_age_limit +
@@ -1280,8 +1507,8 @@ relock:
                LASSERT(!(child_bits & MDS_INODELOCK_LAYOUT));
                if (!OBD_FAIL_CHECK(OBD_FAIL_MDS_NO_LL_GETATTR) &&
                    exp_connect_layout(info->mti_exp) &&
-                   S_ISREG(lu_object_attr(&child->mot_obj.mo_lu)) &&
-                   ldlm_rep != NULL) {
+                   S_ISREG(lu_object_attr(&child->mot_obj)) &&
+                   !mdt_object_remote(child) && ldlm_rep != NULL) {
                        /* try to grant layout lock for regular file. */
                        try_layout = true;
                }
@@ -1301,6 +1528,10 @@ relock:
                                ma_need |= MA_LOV;
                        }
                } else {
+                       /* Do not enqueue the UPDATE lock from MDT(cross-MDT),
+                        * client will enqueue the lock to the remote MDT */
+                       if (mdt_object_remote(child))
+                               child_bits &= ~MDS_INODELOCK_UPDATE;
                        rc = mdt_object_lock(info, child, lhc, child_bits,
                                                MDT_CROSS_LOCK);
                }
@@ -1320,18 +1551,17 @@ relock:
         rc = mdt_getattr_internal(info, child, ma_need);
         if (unlikely(rc != 0)) {
                 mdt_object_unlock(info, child, lhc, 1);
-        } else if (lock) {
-                /* Debugging code. */
-                res_id = &lock->l_resource->lr_name;
-                LDLM_DEBUG(lock, "Returning lock to client");
-                LASSERTF(fid_res_name_eq(mdt_object_fid(child),
-                                         &lock->l_resource->lr_name),
-                         "Lock res_id: %lu/%lu/%lu, Fid: "DFID".\n",
-                         (unsigned long)res_id->name[0],
-                         (unsigned long)res_id->name[1],
-                         (unsigned long)res_id->name[2],
-                         PFID(mdt_object_fid(child)));
-                mdt_pack_size2body(info, child);
+       } else if (lock) {
+               /* Debugging code. */
+               res_id = &lock->l_resource->lr_name;
+               LDLM_DEBUG(lock, "Returning lock to client");
+               LASSERTF(fid_res_name_eq(mdt_object_fid(child),
+                                        &lock->l_resource->lr_name),
+                        "Lock res_id: "DLDLMRES", fid: "DFID"\n",
+                        PLDLMRES(lock->l_resource),
+                        PFID(mdt_object_fid(child)));
+               if (mdt_object_exists(child) && !mdt_object_remote(child))
+                       mdt_pack_size2body(info, child);
         }
         if (lock)
                 LDLM_LOCK_PUT(lock);
@@ -1346,8 +1576,9 @@ out_parent:
 }
 
 /* normal handler: should release the child lock */
-int mdt_getattr_name(struct mdt_thread_info *info)
+int mdt_getattr_name(struct tgt_session_info *tsi)
 {
+       struct mdt_thread_info  *info = tsi2mdt_info(tsi);
         struct mdt_lock_handle *lhc = &info->mti_lh[MDT_LH_CHILD];
         struct mdt_body        *reqbody;
         struct mdt_body        *repbody;
@@ -1379,239 +1610,150 @@ out_shrink:
         rc2 = mdt_fix_reply(info);
         if (rc == 0)
                 rc = rc2;
-        return rc;
+       mdt_thread_info_fini(info);
+       return rc;
 }
 
 static int mdt_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
                          void *karg, void *uarg);
 
-int mdt_set_info(struct mdt_thread_info *info)
+int mdt_set_info(struct tgt_session_info *tsi)
 {
-        struct ptlrpc_request *req = mdt_info_req(info);
-        char *key;
-        void *val;
-        int keylen, vallen, rc = 0;
-        ENTRY;
-
-        rc = req_capsule_server_pack(info->mti_pill);
-        if (rc)
-                RETURN(rc);
+       struct ptlrpc_request   *req = tgt_ses_req(tsi);
+       char                    *key;
+       void                    *val;
+       int                      keylen, vallen, rc = 0;
 
-        key = req_capsule_client_get(info->mti_pill, &RMF_SETINFO_KEY);
-        if (key == NULL) {
-                DEBUG_REQ(D_HA, req, "no set_info key");
-                RETURN(-EFAULT);
-        }
+       ENTRY;
 
-        keylen = req_capsule_get_size(info->mti_pill, &RMF_SETINFO_KEY,
-                                      RCL_CLIENT);
+       key = req_capsule_client_get(tsi->tsi_pill, &RMF_SETINFO_KEY);
+       if (key == NULL) {
+               DEBUG_REQ(D_HA, req, "no set_info key");
+               RETURN(err_serious(-EFAULT));
+       }
 
-        val = req_capsule_client_get(info->mti_pill, &RMF_SETINFO_VAL);
-        if (val == NULL) {
-                DEBUG_REQ(D_HA, req, "no set_info val");
-                RETURN(-EFAULT);
-        }
+       keylen = req_capsule_get_size(tsi->tsi_pill, &RMF_SETINFO_KEY,
+                                     RCL_CLIENT);
 
-        vallen = req_capsule_get_size(info->mti_pill, &RMF_SETINFO_VAL,
-                                      RCL_CLIENT);
+       val = req_capsule_client_get(tsi->tsi_pill, &RMF_SETINFO_VAL);
+       if (val == NULL) {
+               DEBUG_REQ(D_HA, req, "no set_info val");
+               RETURN(err_serious(-EFAULT));
+       }
 
-        /* Swab any part of val you need to here */
-        if (KEY_IS(KEY_READ_ONLY)) {
-                req->rq_status = 0;
-                lustre_msg_set_status(req->rq_repmsg, 0);
+       vallen = req_capsule_get_size(tsi->tsi_pill, &RMF_SETINFO_VAL,
+                                     RCL_CLIENT);
 
+       /* Swab any part of val you need to here */
+       if (KEY_IS(KEY_READ_ONLY)) {
                spin_lock(&req->rq_export->exp_lock);
                if (*(__u32 *)val)
-                       req->rq_export->exp_connect_flags |= OBD_CONNECT_RDONLY;
+                       *exp_connect_flags_ptr(req->rq_export) |=
+                               OBD_CONNECT_RDONLY;
                else
-                       req->rq_export->exp_connect_flags &=~OBD_CONNECT_RDONLY;
+                       *exp_connect_flags_ptr(req->rq_export) &=
+                               ~OBD_CONNECT_RDONLY;
                spin_unlock(&req->rq_export->exp_lock);
+       } else if (KEY_IS(KEY_CHANGELOG_CLEAR)) {
+               struct changelog_setinfo *cs = val;
 
-        } else if (KEY_IS(KEY_CHANGELOG_CLEAR)) {
-                struct changelog_setinfo *cs =
-                        (struct changelog_setinfo *)val;
-                if (vallen != sizeof(*cs)) {
-                        CERROR("Bad changelog_clear setinfo size %d\n", vallen);
-                        RETURN(-EINVAL);
-                }
-                if (ptlrpc_req_need_swab(req)) {
-                        __swab64s(&cs->cs_recno);
-                        __swab32s(&cs->cs_id);
-                }
-
-                rc = mdt_iocontrol(OBD_IOC_CHANGELOG_CLEAR, info->mti_exp,
-                                   vallen, val, NULL);
-                lustre_msg_set_status(req->rq_repmsg, rc);
+               if (vallen != sizeof(*cs)) {
+                       CERROR("%s: bad changelog_clear setinfo size %d\n",
+                              tgt_name(tsi->tsi_tgt), vallen);
+                       RETURN(-EINVAL);
+               }
+               if (ptlrpc_req_need_swab(req)) {
+                       __swab64s(&cs->cs_recno);
+                       __swab32s(&cs->cs_id);
+               }
 
-        } else {
-                RETURN(-EINVAL);
-        }
-        RETURN(0);
+               rc = mdt_iocontrol(OBD_IOC_CHANGELOG_CLEAR, req->rq_export,
+                                  vallen, val, NULL);
+       } else {
+               RETURN(-EINVAL);
+       }
+       RETURN(rc);
 }
 
-/**
- * Top-level handler for MDT connection requests.
- */
-int mdt_connect(struct mdt_thread_info *info)
+int mdt_readpage(struct tgt_session_info *tsi)
 {
-       int rc;
-       struct obd_connect_data *reply;
-       struct obd_export *exp;
-       struct ptlrpc_request *req = mdt_info_req(info);
+       struct mdt_thread_info  *info = mdt_th_info(tsi->tsi_env);
+       struct mdt_object       *object = mdt_obj(tsi->tsi_corpus);
+       struct lu_rdpg          *rdpg = &info->mti_u.rdpg.mti_rdpg;
+       const struct mdt_body   *reqbody = tsi->tsi_mdt_body;
+       struct mdt_body         *repbody;
+       int                      rc;
+       int                      i;
 
-       rc = target_handle_connect(req);
-       if (rc != 0)
-               return err_serious(rc);
+       ENTRY;
 
-       LASSERT(req->rq_export != NULL);
-       info->mti_mdt = mdt_dev(req->rq_export->exp_obd->obd_lu_dev);
-       rc = mdt_init_sec_level(info);
-       if (rc != 0) {
-               obd_disconnect(class_export_get(req->rq_export));
-               return rc;
-       }
+       if (OBD_FAIL_CHECK(OBD_FAIL_MDS_READPAGE_PACK))
+               RETURN(err_serious(-ENOMEM));
 
-       /* To avoid exposing partially initialized connection flags, changes up
-        * to this point have been staged in reply->ocd_connect_flags. Now that
-        * connection handling has completed successfully, atomically update
-        * the connect flags in the shared export data structure. LU-1623 */
-       reply = req_capsule_server_get(info->mti_pill, &RMF_CONNECT_DATA);
-       exp = req->rq_export;
-       spin_lock(&exp->exp_lock);
-       exp->exp_connect_flags = reply->ocd_connect_flags;
-       spin_unlock(&exp->exp_lock);
+       repbody = req_capsule_server_get(tsi->tsi_pill, &RMF_MDT_BODY);
+       if (repbody == NULL || reqbody == NULL)
+                RETURN(err_serious(-EFAULT));
 
-       rc = mdt_init_idmap(info);
-       if (rc != 0)
-               obd_disconnect(class_export_get(req->rq_export));
+        /*
+         * prepare @rdpg before calling lower layers and transfer itself. Here
+         * reqbody->size contains offset of where to start to read and
+         * reqbody->nlink contains number bytes to read.
+         */
+        rdpg->rp_hash = reqbody->size;
+        if (rdpg->rp_hash != reqbody->size) {
+                CERROR("Invalid hash: "LPX64" != "LPX64"\n",
+                       rdpg->rp_hash, reqbody->size);
+                RETURN(-EFAULT);
+        }
 
-       return rc;
-}
+        rdpg->rp_attrs = reqbody->mode;
+       if (exp_connect_flags(tsi->tsi_exp) & OBD_CONNECT_64BITHASH)
+               rdpg->rp_attrs |= LUDA_64BITHASH;
+       rdpg->rp_count  = min_t(unsigned int, reqbody->nlink,
+                               exp_max_brw_size(tsi->tsi_exp));
+       rdpg->rp_npages = (rdpg->rp_count + PAGE_CACHE_SIZE - 1) >>
+                         PAGE_CACHE_SHIFT;
+        OBD_ALLOC(rdpg->rp_pages, rdpg->rp_npages * sizeof rdpg->rp_pages[0]);
+        if (rdpg->rp_pages == NULL)
+                RETURN(-ENOMEM);
 
-int mdt_disconnect(struct mdt_thread_info *info)
-{
-        int rc;
-        ENTRY;
-
-        rc = target_handle_disconnect(mdt_info_req(info));
-        if (rc)
-                rc = err_serious(rc);
-        RETURN(rc);
-}
-
-static int mdt_sendpage(struct mdt_thread_info *info,
-                        struct lu_rdpg *rdpg, int nob)
-{
-        struct ptlrpc_request   *req = mdt_info_req(info);
-        struct obd_export       *exp = req->rq_export;
-        struct ptlrpc_bulk_desc *desc;
-        struct l_wait_info      *lwi = &info->mti_u.rdpg.mti_wait_info;
-        int                      tmpcount;
-        int                      tmpsize;
-        int                      i;
-        int                      rc;
-        ENTRY;
-
-        desc = ptlrpc_prep_bulk_exp(req, rdpg->rp_npages, BULK_PUT_SOURCE,
-                                    MDS_BULK_PORTAL);
-        if (desc == NULL)
-                RETURN(-ENOMEM);
-
-       if (!(exp->exp_connect_flags & OBD_CONNECT_BRW_SIZE))
-               /* old client requires reply size in it's PAGE_SIZE,
-                * which is rdpg->rp_count */
-               nob = rdpg->rp_count;
-
-       for (i = 0, tmpcount = nob; i < rdpg->rp_npages && tmpcount > 0;
-            i++, tmpcount -= tmpsize) {
-                tmpsize = min_t(int, tmpcount, CFS_PAGE_SIZE);
-               ptlrpc_prep_bulk_page_pin(desc, rdpg->rp_pages[i], 0, tmpsize);
-        }
-
-        LASSERT(desc->bd_nob == nob);
-        rc = target_bulk_io(exp, desc, lwi);
-       ptlrpc_free_bulk_pin(desc);
-        RETURN(rc);
-}
-
-int mdt_readpage(struct mdt_thread_info *info)
-{
-        struct mdt_object *object = info->mti_object;
-        struct lu_rdpg    *rdpg = &info->mti_u.rdpg.mti_rdpg;
-        struct mdt_body   *reqbody;
-        struct mdt_body   *repbody;
-        int                rc;
-        int                i;
-        ENTRY;
-
-        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_READPAGE_PACK))
-                RETURN(err_serious(-ENOMEM));
-
-        reqbody = req_capsule_client_get(info->mti_pill, &RMF_MDT_BODY);
-        repbody = req_capsule_server_get(info->mti_pill, &RMF_MDT_BODY);
-        if (reqbody == NULL || repbody == NULL)
-                RETURN(err_serious(-EFAULT));
-
-        /*
-         * prepare @rdpg before calling lower layers and transfer itself. Here
-         * reqbody->size contains offset of where to start to read and
-         * reqbody->nlink contains number bytes to read.
-         */
-        rdpg->rp_hash = reqbody->size;
-        if (rdpg->rp_hash != reqbody->size) {
-                CERROR("Invalid hash: "LPX64" != "LPX64"\n",
-                       rdpg->rp_hash, reqbody->size);
-                RETURN(-EFAULT);
-        }
-
-        rdpg->rp_attrs = reqbody->mode;
-        if (info->mti_exp->exp_connect_flags & OBD_CONNECT_64BITHASH)
-                rdpg->rp_attrs |= LUDA_64BITHASH;
-        rdpg->rp_count  = min_t(unsigned int, reqbody->nlink,
-                                PTLRPC_MAX_BRW_SIZE);
-        rdpg->rp_npages = (rdpg->rp_count + CFS_PAGE_SIZE - 1) >>
-                          CFS_PAGE_SHIFT;
-        OBD_ALLOC(rdpg->rp_pages, rdpg->rp_npages * sizeof rdpg->rp_pages[0]);
-        if (rdpg->rp_pages == NULL)
-                RETURN(-ENOMEM);
-
-        for (i = 0; i < rdpg->rp_npages; ++i) {
-                rdpg->rp_pages[i] = cfs_alloc_page(CFS_ALLOC_STD);
-                if (rdpg->rp_pages[i] == NULL)
-                        GOTO(free_rdpg, rc = -ENOMEM);
-        }
+        for (i = 0; i < rdpg->rp_npages; ++i) {
+               rdpg->rp_pages[i] = alloc_page(GFP_IOFS);
+                if (rdpg->rp_pages[i] == NULL)
+                        GOTO(free_rdpg, rc = -ENOMEM);
+        }
 
         /* call lower layers to fill allocated pages with directory data */
-        rc = mo_readpage(info->mti_env, mdt_object_child(object), rdpg);
-        if (rc < 0)
-                GOTO(free_rdpg, rc);
+       rc = mo_readpage(tsi->tsi_env, mdt_object_child(object), rdpg);
+       if (rc < 0)
+               GOTO(free_rdpg, rc);
 
-        /* send pages to client */
-        rc = mdt_sendpage(info, rdpg, rc);
+       /* send pages to client */
+       rc = tgt_sendpage(tsi, rdpg, rc);
 
-        EXIT;
+       EXIT;
 free_rdpg:
 
-        for (i = 0; i < rdpg->rp_npages; i++)
-                if (rdpg->rp_pages[i] != NULL)
-                        cfs_free_page(rdpg->rp_pages[i]);
-        OBD_FREE(rdpg->rp_pages, rdpg->rp_npages * sizeof rdpg->rp_pages[0]);
+       for (i = 0; i < rdpg->rp_npages; i++)
+               if (rdpg->rp_pages[i] != NULL)
+                       __free_page(rdpg->rp_pages[i]);
+       OBD_FREE(rdpg->rp_pages, rdpg->rp_npages * sizeof rdpg->rp_pages[0]);
 
-        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_SENDPAGE))
-                RETURN(0);
+       if (OBD_FAIL_CHECK(OBD_FAIL_MDS_SENDPAGE))
+               RETURN(0);
 
-        return rc;
+       return rc;
 }
 
 static int mdt_reint_internal(struct mdt_thread_info *info,
                               struct mdt_lock_handle *lhc,
                               __u32 op)
 {
-        struct req_capsule      *pill = info->mti_pill;
-        struct mdt_body         *repbody;
-        int                      rc = 0, rc2;
-        ENTRY;
+       struct req_capsule      *pill = info->mti_pill;
+       struct mdt_body         *repbody;
+       int                      rc = 0, rc2;
 
+       ENTRY;
 
         rc = mdt_reint_unpack(info, op);
         if (rc != 0) {
@@ -1657,7 +1799,8 @@ static int mdt_reint_internal(struct mdt_thread_info *info,
                 GOTO(out_ucred, rc = err_serious(rc));
 
         if (mdt_check_resent(info, mdt_reconstruct, lhc)) {
-                rc = lustre_msg_get_status(mdt_info_req(info)->rq_repmsg);
+               DEBUG_REQ(D_INODE, mdt_info_req(info), "resent opt.");
+               rc = lustre_msg_get_status(mdt_info_req(info)->rq_repmsg);
                 GOTO(out_ucred, rc);
         }
         rc = mdt_reint_rec(info, lhc);
@@ -1672,57 +1815,65 @@ out_shrink:
         return rc;
 }
 
-static long mdt_reint_opcode(struct mdt_thread_info *info,
-                             const struct req_format **fmt)
-{
-        struct mdt_rec_reint *rec;
-        long opc;
-
-        opc = err_serious(-EFAULT);
-        rec = req_capsule_client_get(info->mti_pill, &RMF_REC_REINT);
-        if (rec != NULL) {
-                opc = rec->rr_opcode;
-                DEBUG_REQ(D_INODE, mdt_info_req(info), "reint opt = %ld", opc);
-                if (opc < REINT_MAX && fmt[opc] != NULL)
-                        req_capsule_extend(info->mti_pill, fmt[opc]);
-                else {
-                        CERROR("Unsupported opc: %ld\n", opc);
-                        opc = err_serious(opc);
-                }
-        }
-        return opc;
+static long mdt_reint_opcode(struct ptlrpc_request *req,
+                            const struct req_format **fmt)
+{
+       struct mdt_device       *mdt;
+       struct mdt_rec_reint    *rec;
+       long                     opc;
+
+       rec = req_capsule_client_get(&req->rq_pill, &RMF_REC_REINT);
+       if (rec != NULL) {
+               opc = rec->rr_opcode;
+               DEBUG_REQ(D_INODE, req, "reint opt = %ld", opc);
+               if (opc < REINT_MAX && fmt[opc] != NULL)
+                       req_capsule_extend(&req->rq_pill, fmt[opc]);
+               else {
+                       mdt = mdt_exp2dev(req->rq_export);
+                       CERROR("%s: Unsupported opcode '%ld' from client '%s':"
+                              " rc = %d\n", req->rq_export->exp_obd->obd_name,
+                              opc, mdt->mdt_ldlm_client->cli_name, -EFAULT);
+                       opc = err_serious(-EFAULT);
+               }
+       } else {
+               opc = err_serious(-EFAULT);
+       }
+       return opc;
 }
 
-int mdt_reint(struct mdt_thread_info *info)
+int mdt_reint(struct tgt_session_info *tsi)
 {
-        long opc;
-        int  rc;
-
-        static const struct req_format *reint_fmts[REINT_MAX] = {
-                [REINT_SETATTR]  = &RQF_MDS_REINT_SETATTR,
-                [REINT_CREATE]   = &RQF_MDS_REINT_CREATE,
-                [REINT_LINK]     = &RQF_MDS_REINT_LINK,
-                [REINT_UNLINK]   = &RQF_MDS_REINT_UNLINK,
-                [REINT_RENAME]   = &RQF_MDS_REINT_RENAME,
-                [REINT_OPEN]     = &RQF_MDS_REINT_OPEN,
-                [REINT_SETXATTR] = &RQF_MDS_REINT_SETXATTR
-        };
+       long opc;
+       int  rc;
+       static const struct req_format *reint_fmts[REINT_MAX] = {
+               [REINT_SETATTR]  = &RQF_MDS_REINT_SETATTR,
+               [REINT_CREATE]   = &RQF_MDS_REINT_CREATE,
+               [REINT_LINK]     = &RQF_MDS_REINT_LINK,
+               [REINT_UNLINK]   = &RQF_MDS_REINT_UNLINK,
+               [REINT_RENAME]   = &RQF_MDS_REINT_RENAME,
+               [REINT_OPEN]     = &RQF_MDS_REINT_OPEN,
+               [REINT_SETXATTR] = &RQF_MDS_REINT_SETXATTR,
+               [REINT_RMENTRY]  = &RQF_MDS_REINT_UNLINK,
+               [REINT_MIGRATE]  = &RQF_MDS_REINT_RENAME
+       };
 
-        ENTRY;
+       ENTRY;
 
-        opc = mdt_reint_opcode(info, reint_fmts);
-        if (opc >= 0) {
-                /*
-                 * No lock possible here from client to pass it to reint code
-                 * path.
-                 */
-                rc = mdt_reint_internal(info, NULL, opc);
-        } else {
-                rc = opc;
-        }
+       opc = mdt_reint_opcode(tgt_ses_req(tsi), reint_fmts);
+       if (opc >= 0) {
+               struct mdt_thread_info *info = tsi2mdt_info(tsi);
+               /*
+                * No lock possible here from client to pass it to reint code
+                * path.
+                */
+               rc = mdt_reint_internal(info, NULL, opc);
+               mdt_thread_info_fini(info);
+       } else {
+               rc = opc;
+       }
 
-        info->mti_fail_id = OBD_FAIL_MDS_REINT_NET_REP;
-        RETURN(rc);
+       tsi->tsi_reply_fail_id = OBD_FAIL_MDS_REINT_NET_REP;
+       RETURN(rc);
 }
 
 /* this should sync the whole device */
@@ -1754,93 +1905,60 @@ static int mdt_object_sync(struct mdt_thread_info *info)
         RETURN(rc);
 }
 
-int mdt_sync(struct mdt_thread_info *info)
-{
-        struct ptlrpc_request *req = mdt_info_req(info);
-        struct req_capsule *pill = info->mti_pill;
-        struct mdt_body *body;
-        int rc;
-        ENTRY;
-
-        /* The fid may be zero, so we req_capsule_set manually */
-        req_capsule_set(pill, &RQF_MDS_SYNC);
-
-        body = req_capsule_client_get(pill, &RMF_MDT_BODY);
-        if (body == NULL)
-                RETURN(err_serious(-EINVAL));
-
-        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_SYNC_PACK))
-                RETURN(err_serious(-ENOMEM));
-
-        if (fid_seq(&body->fid1) == 0) {
-                /* sync the whole device */
-                rc = req_capsule_server_pack(pill);
-                if (rc == 0)
-                        rc = mdt_device_sync(info->mti_env, info->mti_mdt);
-                else
-                        rc = err_serious(rc);
-        } else {
-                /* sync an object */
-                rc = mdt_unpack_req_pack_rep(info, HABEO_CORPUS|HABEO_REFERO);
-                if (rc == 0) {
-                        rc = mdt_object_sync(info);
-                        if (rc == 0) {
-                                const struct lu_fid *fid;
-                                struct lu_attr *la = &info->mti_attr.ma_attr;
-
-                                info->mti_attr.ma_need = MA_INODE;
-                                info->mti_attr.ma_valid = 0;
-                               rc = mdt_attr_get_complex(info, info->mti_object,
-                                                         &info->mti_attr);
-                                if (rc == 0) {
-                                        body = req_capsule_server_get(pill,
-                                                                &RMF_MDT_BODY);
-                                        fid = mdt_object_fid(info->mti_object);
-                                        mdt_pack_attr2body(info, body, la, fid);
-                                }
-                        }
-                } else
-                        rc = err_serious(rc);
-        }
-        if (rc == 0)
-               mdt_counter_incr(req, LPROC_MDT_SYNC);
-
-        RETURN(rc);
-}
-
-/*
- * Quotacheck handler.
- * in-kernel quotacheck isn't supported any more.
- */
-int mdt_quotacheck(struct mdt_thread_info *info)
+int mdt_sync(struct tgt_session_info *tsi)
 {
-       struct obd_quotactl     *oqctl;
+       struct ptlrpc_request   *req = tgt_ses_req(tsi);
+       struct req_capsule      *pill = tsi->tsi_pill;
+       struct mdt_body         *body;
        int                      rc;
+
        ENTRY;
 
-       oqctl = req_capsule_client_get(info->mti_pill, &RMF_OBD_QUOTACTL);
-       if (oqctl == NULL)
-               RETURN(err_serious(-EPROTO));
+       if (OBD_FAIL_CHECK(OBD_FAIL_MDS_SYNC_PACK))
+               RETURN(err_serious(-ENOMEM));
 
-       rc = req_capsule_server_pack(info->mti_pill);
-       if (rc)
-               RETURN(err_serious(rc));
+       if (fid_seq(&tsi->tsi_mdt_body->fid1) == 0) {
+               rc = mdt_device_sync(tsi->tsi_env, mdt_exp2dev(tsi->tsi_exp));
+       } else {
+               struct mdt_thread_info *info = tsi2mdt_info(tsi);
+
+               /* sync an object */
+               rc = mdt_object_sync(info);
+               if (rc == 0) {
+                       const struct lu_fid *fid;
+                       struct lu_attr *la = &info->mti_attr.ma_attr;
+
+                       info->mti_attr.ma_need = MA_INODE;
+                       info->mti_attr.ma_valid = 0;
+                       rc = mdt_attr_get_complex(info, info->mti_object,
+                                                 &info->mti_attr);
+                       if (rc == 0) {
+                               body = req_capsule_server_get(pill,
+                                                             &RMF_MDT_BODY);
+                               fid = mdt_object_fid(info->mti_object);
+                               mdt_pack_attr2body(info, body, la, fid);
+                       }
+               }
+               mdt_thread_info_fini(info);
+       }
+       if (rc == 0)
+               mdt_counter_incr(req, LPROC_MDT_SYNC);
 
-       /* deprecated, not used any more */
-       RETURN(-EOPNOTSUPP);
+       RETURN(rc);
 }
 
 /*
  * Handle quota control requests to consult current usage/limit, but also
  * to configure quota enforcement
  */
-int mdt_quotactl(struct mdt_thread_info *info)
+int mdt_quotactl(struct tgt_session_info *tsi)
 {
-       struct obd_export       *exp  = info->mti_exp;
-       struct req_capsule      *pill = info->mti_pill;
+       struct obd_export       *exp  = tsi->tsi_exp;
+       struct req_capsule      *pill = tsi->tsi_pill;
        struct obd_quotactl     *oqctl, *repoqc;
        int                      id, rc;
-       struct lu_device        *qmt = info->mti_mdt->mdt_qmt_dev;
+       struct mdt_device       *mdt = mdt_exp2dev(exp);
+       struct lu_device        *qmt = mdt->mdt_qmt_dev;
        ENTRY;
 
        oqctl = req_capsule_client_get(pill, &RMF_OBD_QUOTACTL);
@@ -1881,7 +1999,7 @@ int mdt_quotactl(struct mdt_thread_info *info)
        if (exp_connect_rmtclient(exp)) {
                struct lustre_idmap_table *idmap;
 
-               idmap = mdt_req2med(mdt_info_req(info))->med_idmap;
+               idmap = exp->exp_mdt_data.med_idmap;
 
                if (unlikely(oqctl->qc_cmd != Q_GETQUOTA &&
                             oqctl->qc_cmd != Q_GETINFO))
@@ -1916,13 +2034,13 @@ int mdt_quotactl(struct mdt_thread_info *info)
        case Q_SETQUOTA:
        case Q_GETQUOTA:
                /* forward quotactl request to QMT */
-               rc = qmt_hdls.qmth_quotactl(info->mti_env, qmt, oqctl);
+               rc = qmt_hdls.qmth_quotactl(tsi->tsi_env, qmt, oqctl);
                break;
 
        case Q_GETOINFO:
        case Q_GETOQUOTA:
                /* slave quotactl */
-               rc = lquotactl_slv(info->mti_env, info->mti_mdt->mdt_bottom,
+               rc = lquotactl_slv(tsi->tsi_env, tsi->tsi_tgt->lut_bottom,
                                   oqctl);
                break;
 
@@ -1938,119 +2056,6 @@ int mdt_quotactl(struct mdt_thread_info *info)
        RETURN(rc);
 }
 
-/*
- * OBD PING and other handlers.
- */
-int mdt_obd_ping(struct mdt_thread_info *info)
-{
-        int rc;
-        ENTRY;
-
-        req_capsule_set(info->mti_pill, &RQF_OBD_PING);
-
-        rc = target_handle_ping(mdt_info_req(info));
-        if (rc < 0)
-                rc = err_serious(rc);
-        RETURN(rc);
-}
-
-/*
- * OBD_IDX_READ handler
- */
-int mdt_obd_idx_read(struct mdt_thread_info *info)
-{
-       struct mdt_device       *mdt = info->mti_mdt;
-       struct lu_rdpg          *rdpg = &info->mti_u.rdpg.mti_rdpg;
-       struct idx_info         *req_ii, *rep_ii;
-       int                      rc, i;
-       ENTRY;
-
-       memset(rdpg, 0, sizeof(*rdpg));
-       req_capsule_set(info->mti_pill, &RQF_OBD_IDX_READ);
-
-       /* extract idx_info buffer from request & reply */
-       req_ii = req_capsule_client_get(info->mti_pill, &RMF_IDX_INFO);
-       if (req_ii == NULL || req_ii->ii_magic != IDX_INFO_MAGIC)
-               RETURN(err_serious(-EPROTO));
-
-       rc = req_capsule_server_pack(info->mti_pill);
-       if (rc)
-               RETURN(err_serious(rc));
-
-       rep_ii = req_capsule_server_get(info->mti_pill, &RMF_IDX_INFO);
-       if (rep_ii == NULL)
-               RETURN(err_serious(-EFAULT));
-       rep_ii->ii_magic = IDX_INFO_MAGIC;
-
-       /* extract hash to start with */
-       rdpg->rp_hash = req_ii->ii_hash_start;
-
-       /* extract requested attributes */
-       rdpg->rp_attrs = req_ii->ii_attrs;
-
-       /* check that fid packed in request is valid and supported */
-       if (!fid_is_sane(&req_ii->ii_fid))
-               RETURN(-EINVAL);
-       rep_ii->ii_fid = req_ii->ii_fid;
-
-       /* copy flags */
-       rep_ii->ii_flags = req_ii->ii_flags;
-
-       /* compute number of pages to allocate, ii_count is the number of 4KB
-        * containers */
-       if (req_ii->ii_count <= 0)
-               GOTO(out, rc = -EFAULT);
-       rdpg->rp_count = min_t(unsigned int, req_ii->ii_count << LU_PAGE_SHIFT,
-                              PTLRPC_MAX_BRW_SIZE);
-       rdpg->rp_npages = (rdpg->rp_count + CFS_PAGE_SIZE -1) >> CFS_PAGE_SHIFT;
-
-       /* allocate pages to store the containers */
-       OBD_ALLOC(rdpg->rp_pages, rdpg->rp_npages * sizeof(rdpg->rp_pages[0]));
-       if (rdpg->rp_pages == NULL)
-               GOTO(out, rc = -ENOMEM);
-       for (i = 0; i < rdpg->rp_npages; i++) {
-               rdpg->rp_pages[i] = cfs_alloc_page(CFS_ALLOC_STD);
-               if (rdpg->rp_pages[i] == NULL)
-                       GOTO(out, rc = -ENOMEM);
-       }
-
-       /* populate pages with key/record pairs */
-       rc = dt_index_read(info->mti_env, mdt->mdt_bottom, rep_ii, rdpg);
-       if (rc < 0)
-               GOTO(out, rc);
-
-       LASSERTF(rc <= rdpg->rp_count, "dt_index_read() returned more than "
-                "asked %d > %d\n", rc, rdpg->rp_count);
-
-       /* send pages to client */
-       rc = mdt_sendpage(info, rdpg, rc);
-
-       GOTO(out, rc);
-out:
-       if (rdpg->rp_pages) {
-               for (i = 0; i < rdpg->rp_npages; i++)
-                       if (rdpg->rp_pages[i])
-                               cfs_free_page(rdpg->rp_pages[i]);
-               OBD_FREE(rdpg->rp_pages,
-                        rdpg->rp_npages * sizeof(rdpg->rp_pages[0]));
-       }
-       return rc;
-}
-
-int mdt_obd_log_cancel(struct mdt_thread_info *info)
-{
-        return err_serious(-EOPNOTSUPP);
-}
-
-int mdt_obd_qc_callback(struct mdt_thread_info *info)
-{
-        return err_serious(-EOPNOTSUPP);
-}
-
-/*
- * LLOG handlers.
- */
-
 /** clone llog ctxt from child (mdd)
  * This allows remote llog (replicator) access.
  * We can either pass all llog RPCs (eg mdt_llog_create) on to child where the
@@ -2095,150 +2100,45 @@ static int mdt_llog_ctxt_unclone(const struct lu_env *env,
         return 0;
 }
 
-int mdt_llog_create(struct mdt_thread_info *info)
-{
-       int rc;
-
-       req_capsule_set(info->mti_pill, &RQF_LLOG_ORIGIN_HANDLE_CREATE);
-       rc = llog_origin_handle_open(mdt_info_req(info));
-       return (rc < 0 ? err_serious(rc) : rc);
-}
-
-int mdt_llog_destroy(struct mdt_thread_info *info)
-{
-        int rc;
-
-        req_capsule_set(info->mti_pill, &RQF_LLOG_ORIGIN_HANDLE_DESTROY);
-        rc = llog_origin_handle_destroy(mdt_info_req(info));
-        return (rc < 0 ? err_serious(rc) : rc);
-}
-
-int mdt_llog_read_header(struct mdt_thread_info *info)
-{
-        int rc;
-
-        req_capsule_set(info->mti_pill, &RQF_LLOG_ORIGIN_HANDLE_READ_HEADER);
-        rc = llog_origin_handle_read_header(mdt_info_req(info));
-        return (rc < 0 ? err_serious(rc) : rc);
-}
-
-int mdt_llog_next_block(struct mdt_thread_info *info)
-{
-        int rc;
-
-        req_capsule_set(info->mti_pill, &RQF_LLOG_ORIGIN_HANDLE_NEXT_BLOCK);
-        rc = llog_origin_handle_next_block(mdt_info_req(info));
-        return (rc < 0 ? err_serious(rc) : rc);
-}
-
-int mdt_llog_prev_block(struct mdt_thread_info *info)
-{
-        int rc;
-
-        req_capsule_set(info->mti_pill, &RQF_LLOG_ORIGIN_HANDLE_PREV_BLOCK);
-        rc = llog_origin_handle_prev_block(mdt_info_req(info));
-        return (rc < 0 ? err_serious(rc) : rc);
-}
-
-
-/*
- * DLM handlers.
- */
-
-static struct ldlm_callback_suite cbs = {
-       .lcs_completion = ldlm_server_completion_ast,
-       .lcs_blocking   = ldlm_server_blocking_ast,
-       .lcs_glimpse    = ldlm_server_glimpse_ast
-};
-
-int mdt_enqueue(struct mdt_thread_info *info)
-{
-        struct ptlrpc_request *req;
-        int rc;
-
-        /*
-         * info->mti_dlm_req already contains swapped and (if necessary)
-         * converted dlm request.
-         */
-        LASSERT(info->mti_dlm_req != NULL);
-
-        req = mdt_info_req(info);
-        rc = ldlm_handle_enqueue0(info->mti_mdt->mdt_namespace,
-                                  req, info->mti_dlm_req, &cbs);
-        info->mti_fail_id = OBD_FAIL_LDLM_REPLY;
-        return rc ? err_serious(rc) : req->rq_status;
-}
-
-int mdt_convert(struct mdt_thread_info *info)
-{
-        int rc;
-        struct ptlrpc_request *req;
-
-        LASSERT(info->mti_dlm_req);
-        req = mdt_info_req(info);
-        rc = ldlm_handle_convert0(req, info->mti_dlm_req);
-        return rc ? err_serious(rc) : req->rq_status;
-}
-
-int mdt_bl_callback(struct mdt_thread_info *info)
-{
-        CERROR("bl callbacks should not happen on MDS\n");
-        LBUG();
-        return err_serious(-EOPNOTSUPP);
-}
-
-int mdt_cp_callback(struct mdt_thread_info *info)
-{
-        CERROR("cp callbacks should not happen on MDS\n");
-        LBUG();
-        return err_serious(-EOPNOTSUPP);
-}
-
 /*
  * sec context handlers
  */
-int mdt_sec_ctx_handle(struct mdt_thread_info *info)
+int mdt_sec_ctx_handle(struct tgt_session_info *tsi)
 {
-        int rc;
-
-        rc = mdt_handle_idmap(info);
+       int rc;
 
-        if (unlikely(rc)) {
-                struct ptlrpc_request *req = mdt_info_req(info);
-                __u32                  opc;
+       rc = mdt_handle_idmap(tsi);
+       if (unlikely(rc)) {
+               struct ptlrpc_request   *req = tgt_ses_req(tsi);
+               __u32                    opc;
 
-                opc = lustre_msg_get_opc(req->rq_reqmsg);
-                if (opc == SEC_CTX_INIT || opc == SEC_CTX_INIT_CONT)
-                        sptlrpc_svc_ctx_invalidate(req);
-        }
+               opc = lustre_msg_get_opc(req->rq_reqmsg);
+               if (opc == SEC_CTX_INIT || opc == SEC_CTX_INIT_CONT)
+                       sptlrpc_svc_ctx_invalidate(req);
+       }
 
-        CFS_FAIL_TIMEOUT(OBD_FAIL_SEC_CTX_HDL_PAUSE, cfs_fail_val);
+       CFS_FAIL_TIMEOUT(OBD_FAIL_SEC_CTX_HDL_PAUSE, cfs_fail_val);
 
-        return rc;
+       return rc;
 }
 
 /*
  * quota request handlers
  */
-int mdt_quota_dqacq(struct mdt_thread_info *info)
+int mdt_quota_dqacq(struct tgt_session_info *tsi)
 {
-       struct lu_device        *qmt = info->mti_mdt->mdt_qmt_dev;
+       struct mdt_device       *mdt = mdt_exp2dev(tsi->tsi_exp);
+       struct lu_device        *qmt = mdt->mdt_qmt_dev;
        int                      rc;
        ENTRY;
 
        if (qmt == NULL)
                RETURN(err_serious(-EOPNOTSUPP));
 
-       rc = qmt_hdls.qmth_dqacq(info->mti_env, qmt, mdt_info_req(info));
+       rc = qmt_hdls.qmth_dqacq(tsi->tsi_env, qmt, tgt_ses_req(tsi));
        RETURN(rc);
 }
 
-static struct mdt_object *mdt_obj(struct lu_object *o)
-{
-        LASSERT(lu_device_is_mdt(o->lo_dev));
-        return container_of0(o, struct mdt_object, mot_obj.mo_lu);
-}
-
 struct mdt_object *mdt_object_new(const struct lu_env *env,
                                  struct mdt_device *d,
                                  const struct lu_fid *f)
@@ -2249,7 +2149,7 @@ struct mdt_object *mdt_object_new(const struct lu_env *env,
        ENTRY;
 
        CDEBUG(D_INFO, "Allocate object for "DFID"\n", PFID(f));
-       o = lu_object_find(env, &d->mdt_md_dev.md_lu_dev, f, &conf);
+       o = lu_object_find(env, &d->mdt_lu_dev, f, &conf);
        if (unlikely(IS_ERR(o)))
                m = (struct mdt_object *)o;
        else
@@ -2258,20 +2158,21 @@ struct mdt_object *mdt_object_new(const struct lu_env *env,
 }
 
 struct mdt_object *mdt_object_find(const struct lu_env *env,
-                                   struct mdt_device *d,
-                                   const struct lu_fid *f)
+                                  struct mdt_device *d,
+                                  const struct lu_fid *f)
 {
-        struct lu_object *o;
-        struct mdt_object *m;
-        ENTRY;
+       struct lu_object *o;
+       struct mdt_object *m;
+       ENTRY;
 
-        CDEBUG(D_INFO, "Find object for "DFID"\n", PFID(f));
-        o = lu_object_find(env, &d->mdt_md_dev.md_lu_dev, f, NULL);
-        if (unlikely(IS_ERR(o)))
-                m = (struct mdt_object *)o;
-        else
-                m = mdt_obj(o);
-        RETURN(m);
+       CDEBUG(D_INFO, "Find object for "DFID"\n", PFID(f));
+       o = lu_object_find(env, &d->mdt_lu_dev, f, NULL);
+       if (unlikely(IS_ERR(o)))
+               m = (struct mdt_object *)o;
+       else
+               m = mdt_obj(o);
+
+       RETURN(m);
 }
 
 /**
@@ -2376,9 +2277,68 @@ int mdt_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
         RETURN(rc);
 }
 
-static int mdt_object_lock0(struct mdt_thread_info *info, struct mdt_object *o,
-                           struct mdt_lock_handle *lh, __u64 ibits,
-                           bool nonblock, int locality)
+/* Used for cross-MDT lock */
+int mdt_remote_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
+                           void *data, int flag)
+{
+       struct lustre_handle lockh;
+       int               rc;
+
+       switch (flag) {
+       case LDLM_CB_BLOCKING:
+               ldlm_lock2handle(lock, &lockh);
+               rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
+               if (rc < 0) {
+                       CDEBUG(D_INODE, "ldlm_cli_cancel: %d\n", rc);
+                       RETURN(rc);
+               }
+               break;
+       case LDLM_CB_CANCELING:
+               LDLM_DEBUG(lock, "Revoke remote lock\n");
+               break;
+       default:
+               LBUG();
+       }
+       RETURN(0);
+}
+
+int mdt_remote_object_lock(struct mdt_thread_info *mti,
+                          struct mdt_object *o, const struct lu_fid *fid,
+                          struct lustre_handle *lh, ldlm_mode_t mode,
+                          __u64 ibits)
+{
+       struct ldlm_enqueue_info *einfo = &mti->mti_einfo;
+       ldlm_policy_data_t *policy = &mti->mti_policy;
+       struct ldlm_res_id *res_id = &mti->mti_res_id;
+       int rc = 0;
+       ENTRY;
+
+       LASSERT(mdt_object_remote(o));
+
+       LASSERT(ibits == MDS_INODELOCK_UPDATE);
+
+       fid_build_reg_res_name(fid, res_id);
+
+       memset(einfo, 0, sizeof(*einfo));
+       einfo->ei_type = LDLM_IBITS;
+       einfo->ei_mode = mode;
+       einfo->ei_cb_bl = mdt_remote_blocking_ast;
+       einfo->ei_cb_cp = ldlm_completion_ast;
+       einfo->ei_enq_slave = 0;
+       einfo->ei_res_id = res_id;
+
+       memset(policy, 0, sizeof(*policy));
+       policy->l_inodebits.bits = ibits;
+
+       rc = mo_object_lock(mti->mti_env, mdt_object_child(o), lh, einfo,
+                           policy);
+       RETURN(rc);
+}
+
+static int mdt_object_local_lock(struct mdt_thread_info *info,
+                                struct mdt_object *o,
+                                struct mdt_lock_handle *lh, __u64 ibits,
+                                bool nonblock, int locality)
 {
         struct ldlm_namespace *ns = info->mti_mdt->mdt_namespace;
         ldlm_policy_data_t *policy = &info->mti_policy;
@@ -2392,28 +2352,19 @@ static int mdt_object_lock0(struct mdt_thread_info *info, struct mdt_object *o,
         LASSERT(lh->mlh_reg_mode != LCK_MINMODE);
         LASSERT(lh->mlh_type != MDT_NUL_LOCK);
 
-        if (mdt_object_exists(o) < 0) {
-                if (locality == MDT_CROSS_LOCK) {
-                        /* cross-ref object fix */
-                        ibits &= ~MDS_INODELOCK_UPDATE;
-                        ibits |= MDS_INODELOCK_LOOKUP;
-                } else {
-                        LASSERT(!(ibits & MDS_INODELOCK_UPDATE));
-                        LASSERT(ibits & MDS_INODELOCK_LOOKUP);
-                }
-                /* No PDO lock on remote object */
-                LASSERT(lh->mlh_type != MDT_PDO_LOCK);
-        }
+       /* Only enqueue LOOKUP lock for remote object */
+       if (mdt_object_remote(o))
+               LASSERT(ibits == MDS_INODELOCK_LOOKUP);
 
-        if (lh->mlh_type == MDT_PDO_LOCK) {
+       if (lh->mlh_type == MDT_PDO_LOCK) {
                 /* check for exists after object is locked */
                 if (mdt_object_exists(o) == 0) {
                         /* Non-existent object shouldn't have PDO lock */
                         RETURN(-ESTALE);
                 } else {
                         /* Non-dir object shouldn't have PDO lock */
-                        if (!S_ISDIR(lu_object_attr(&o->mot_obj.mo_lu)))
-                                RETURN(-ENOTDIR);
+                       if (!S_ISDIR(lu_object_attr(&o->mot_obj)))
+                               RETURN(-ENOTDIR);
                 }
         }
 
@@ -2473,10 +2424,65 @@ static int mdt_object_lock0(struct mdt_thread_info *info, struct mdt_object *o,
         RETURN(rc);
 }
 
+int mdt_object_lock_internal(struct mdt_thread_info *info, struct mdt_object *o,
+                            struct mdt_lock_handle *lh, __u64 ibits,
+                            bool nonblock, int locality)
+{
+       int rc;
+       ENTRY;
+
+       if (!mdt_object_remote(o))
+               return mdt_object_local_lock(info, o, lh, ibits, nonblock,
+                                            locality);
+
+       if (locality == MDT_LOCAL_LOCK) {
+               CERROR("%s: try to get local lock for remote object"
+                      DFID".\n", mdt_obd_name(info->mti_mdt),
+                      PFID(mdt_object_fid(o)));
+               RETURN(-EPROTO);
+       }
+
+       /* XXX do not support PERM/LAYOUT/XATTR lock for remote object yet */
+       ibits &= ~(MDS_INODELOCK_PERM | MDS_INODELOCK_LAYOUT |
+                  MDS_INODELOCK_XATTR);
+       if (ibits & MDS_INODELOCK_UPDATE) {
+               /* Sigh, PDO needs to enqueue 2 locks right now, but
+                * enqueue RPC can only request 1 lock, to avoid extra
+                * RPC, so it will instead enqueue EX lock for remote
+                * object anyway XXX*/
+               if (lh->mlh_type == MDT_PDO_LOCK &&
+                   lh->mlh_pdo_hash != 0) {
+                       CDEBUG(D_INFO, "%s: "DFID" convert PDO lock to"
+                              "EX lock.\n", mdt_obd_name(info->mti_mdt),
+                              PFID(mdt_object_fid(o)));
+                       lh->mlh_pdo_hash = 0;
+                       lh->mlh_rreg_mode = LCK_EX;
+                       lh->mlh_type = MDT_REG_LOCK;
+               }
+               rc = mdt_remote_object_lock(info, o, mdt_object_fid(o),
+                                           &lh->mlh_rreg_lh,
+                                           lh->mlh_rreg_mode,
+                                           MDS_INODELOCK_UPDATE);
+               if (rc != ELDLM_OK)
+                       RETURN(rc);
+       }
+
+       /* Only enqueue LOOKUP lock for remote object */
+       if (ibits & MDS_INODELOCK_LOOKUP) {
+               rc = mdt_object_local_lock(info, o, lh,
+                                          MDS_INODELOCK_LOOKUP,
+                                          nonblock, locality);
+               if (rc != ELDLM_OK)
+                       RETURN(rc);
+       }
+
+       RETURN(0);
+}
+
 int mdt_object_lock(struct mdt_thread_info *info, struct mdt_object *o,
                    struct mdt_lock_handle *lh, __u64 ibits, int locality)
 {
-       return mdt_object_lock0(info, o, lh, ibits, false, locality);
+       return mdt_object_lock_internal(info, o, lh, ibits, false, locality);
 }
 
 int mdt_object_lock_try(struct mdt_thread_info *info, struct mdt_object *o,
@@ -2485,7 +2491,7 @@ int mdt_object_lock_try(struct mdt_thread_info *info, struct mdt_object *o,
        struct mdt_lock_handle tmp = *lh;
        int rc;
 
-       rc = mdt_object_lock0(info, o, &tmp, ibits, true, locality);
+       rc = mdt_object_lock_internal(info, o, &tmp, ibits, true, locality);
        if (rc == 0)
                *lh = tmp;
 
@@ -2523,15 +2529,21 @@ void mdt_save_lock(struct mdt_thread_info *info, struct lustre_handle *h,
 
                         LASSERTF(lock != NULL, "no lock for cookie "LPX64"\n",
                                  h->cookie);
-                        CDEBUG(D_HA, "request = %p reply state = %p"
-                               " transno = "LPD64"\n",
-                               req, req->rq_reply_state, req->rq_transno);
-                        if (mdt_cos_is_enabled(mdt)) {
-                                no_ack = 1;
-                                ldlm_lock_downgrade(lock, LCK_COS);
-                                mode = LCK_COS;
-                        }
-                        ptlrpc_save_lock(req, h, mode, no_ack);
+                       /* there is no request if mdt_object_unlock() is called
+                        * from mdt_export_cleanup()->mdt_add_dirty_flag() */
+                       if (likely(req != NULL)) {
+                               CDEBUG(D_HA, "request = %p reply state = %p"
+                                      " transno = "LPD64"\n", req,
+                                      req->rq_reply_state, req->rq_transno);
+                               if (mdt_cos_is_enabled(mdt)) {
+                                       no_ack = 1;
+                                       ldlm_lock_downgrade(lock, LCK_COS);
+                                       mode = LCK_COS;
+                               }
+                               ptlrpc_save_lock(req, h, mode, no_ack);
+                       } else {
+                               ldlm_lock_decref(h, mode);
+                       }
                         if (mdt_is_lock_sync(lock)) {
                                 CDEBUG(D_HA, "found sync-lock,"
                                        " async commit started\n");
@@ -2566,6 +2578,9 @@ void mdt_object_unlock(struct mdt_thread_info *info, struct mdt_object *o,
         mdt_save_lock(info, &lh->mlh_pdo_lh, lh->mlh_pdo_mode, decref);
         mdt_save_lock(info, &lh->mlh_reg_lh, lh->mlh_reg_mode, decref);
 
+       if (lustre_handle_is_used(&lh->mlh_rreg_lh))
+               ldlm_lock_decref(&lh->mlh_rreg_lh, lh->mlh_rreg_mode);
+
         EXIT;
 }
 
@@ -2599,40 +2614,6 @@ void mdt_object_unlock_put(struct mdt_thread_info * info,
         mdt_object_put(info->mti_env, o);
 }
 
-struct mdt_handler *mdt_handler_find(__u32 opc, struct mdt_opc_slice *supported)
-{
-        struct mdt_opc_slice *s;
-        struct mdt_handler   *h;
-
-        h = NULL;
-        for (s = supported; s->mos_hs != NULL; s++) {
-                if (s->mos_opc_start <= opc && opc < s->mos_opc_end) {
-                        h = s->mos_hs + (opc - s->mos_opc_start);
-                        if (likely(h->mh_opc != 0))
-                                LASSERTF(h->mh_opc == opc,
-                                         "opcode mismatch %d != %d\n",
-                                         h->mh_opc, opc);
-                        else
-                                h = NULL; /* unsupported opc */
-                        break;
-                }
-        }
-        return h;
-}
-
-static int mdt_lock_resname_compat(struct mdt_device *m,
-                                   struct ldlm_request *req)
-{
-        /* XXX something... later. */
-        return 0;
-}
-
-static int mdt_lock_reply_compat(struct mdt_device *m, struct ldlm_reply *rep)
-{
-        /* XXX something... later. */
-        return 0;
-}
-
 /*
  * Generic code handling requests that have struct mdt_body passed in:
  *
@@ -2727,150 +2708,13 @@ static int mdt_unpack_req_pack_rep(struct mdt_thread_info *info, __u32 flags)
 
 static int mdt_init_capa_ctxt(const struct lu_env *env, struct mdt_device *m)
 {
-        struct md_device *next = m->mdt_child;
+       struct md_device *next = m->mdt_child;
 
-        return next->md_ops->mdo_init_capa_ctxt(env, next,
-                                                m->mdt_opts.mo_mds_capa,
-                                                m->mdt_capa_timeout,
-                                                m->mdt_capa_alg,
-                                                m->mdt_capa_keys);
-}
-
-/*
- * Invoke handler for this request opc. Also do necessary preprocessing
- * (according to handler ->mh_flags), and post-processing (setting of
- * ->last_{xid,committed}).
- */
-static int mdt_req_handle(struct mdt_thread_info *info,
-                          struct mdt_handler *h, struct ptlrpc_request *req)
-{
-        int   rc, serious = 0;
-        __u32 flags;
-
-        ENTRY;
-
-        LASSERT(h->mh_act != NULL);
-        LASSERT(h->mh_opc == lustre_msg_get_opc(req->rq_reqmsg));
-        LASSERT(current->journal_info == NULL);
-
-        /*
-         * Checking for various OBD_FAIL_$PREF_$OPC_NET codes. _Do_ not try
-         * to put same checks into handlers like mdt_close(), mdt_reint(),
-         * etc., without talking to mdt authors first. Checking same thing
-         * there again is useless and returning 0 error without packing reply
-         * is buggy! Handlers either pack reply or return error.
-         *
-         * We return 0 here and do not send any reply in order to emulate
-         * network failure. Do not send any reply in case any of NET related
-         * fail_id has occured.
-         */
-        if (OBD_FAIL_CHECK_ORSET(h->mh_fail_id, OBD_FAIL_ONCE))
-                RETURN(0);
-
-        rc = 0;
-        flags = h->mh_flags;
-        LASSERT(ergo(flags & (HABEO_CORPUS|HABEO_REFERO), h->mh_fmt != NULL));
-
-        if (h->mh_fmt != NULL) {
-                req_capsule_set(info->mti_pill, h->mh_fmt);
-                rc = mdt_unpack_req_pack_rep(info, flags);
-        }
-
-        if (rc == 0 && flags & MUTABOR &&
-            req->rq_export->exp_connect_flags & OBD_CONNECT_RDONLY)
-                /* should it be rq_status? */
-                rc = -EROFS;
-
-        if (rc == 0 && flags & HABEO_CLAVIS) {
-                struct ldlm_request *dlm_req;
-
-                LASSERT(h->mh_fmt != NULL);
-
-                dlm_req = req_capsule_client_get(info->mti_pill, &RMF_DLM_REQ);
-                if (dlm_req != NULL) {
-                        if (unlikely(dlm_req->lock_desc.l_resource.lr_type ==
-                                        LDLM_IBITS &&
-                                     dlm_req->lock_desc.l_policy_data.\
-                                        l_inodebits.bits == 0)) {
-                                /*
-                                 * Lock without inodebits makes no sense and
-                                 * will oops later in ldlm. If client miss to
-                                 * set such bits, do not trigger ASSERTION.
-                                 *
-                                 * For liblustre flock case, it maybe zero.
-                                 */
-                                rc = -EPROTO;
-                        } else {
-                                if (info->mti_mdt->mdt_opts.mo_compat_resname)
-                                        rc = mdt_lock_resname_compat(
-                                                                info->mti_mdt,
-                                                                dlm_req);
-                                info->mti_dlm_req = dlm_req;
-                        }
-                } else {
-                        rc = -EFAULT;
-                }
-        }
-
-        /* capability setting changed via /proc, needs reinitialize ctxt */
-        if (info->mti_mdt && info->mti_mdt->mdt_capa_conf) {
-                mdt_init_capa_ctxt(info->mti_env, info->mti_mdt);
-                info->mti_mdt->mdt_capa_conf = 0;
-        }
-
-        if (likely(rc == 0)) {
-                /*
-                 * Process request, there can be two types of rc:
-                 * 1) errors with msg unpack/pack, other failures outside the
-                 * operation itself. This is counted as serious errors;
-                 * 2) errors during fs operation, should be placed in rq_status
-                 * only
-                 */
-                rc = h->mh_act(info);
-                if (rc == 0 &&
-                    !req->rq_no_reply && req->rq_reply_state == NULL) {
-                        DEBUG_REQ(D_ERROR, req, "MDT \"handler\" %s did not "
-                                  "pack reply and returned 0 error\n",
-                                  h->mh_name);
-                        LBUG();
-                }
-                serious = is_serious(rc);
-                rc = clear_serious(rc);
-        } else
-                serious = 1;
-
-        req->rq_status = rc;
-
-        /*
-         * ELDLM_* codes which > 0 should be in rq_status only as well as
-         * all non-serious errors.
-         */
-        if (rc > 0 || !serious)
-                rc = 0;
-
-        LASSERT(current->journal_info == NULL);
-
-        if (rc == 0 && (flags & HABEO_CLAVIS) &&
-            info->mti_mdt->mdt_opts.mo_compat_resname) {
-                struct ldlm_reply *dlmrep;
-
-                dlmrep = req_capsule_server_get(info->mti_pill, &RMF_DLM_REP);
-                if (dlmrep != NULL)
-                        rc = mdt_lock_reply_compat(info->mti_mdt, dlmrep);
-        }
-
-        /* If we're DISCONNECTing, the mdt_export_data is already freed */
-        if (likely(rc == 0 && req->rq_export && h->mh_opc != MDS_DISCONNECT))
-                target_committed_to_req(req);
-
-        if (unlikely(req_is_replay(req) &&
-                     lustre_msg_get_transno(req->rq_reqmsg) == 0)) {
-                DEBUG_REQ(D_ERROR, req, "transno is 0 during REPLAY");
-                LBUG();
-        }
-
-        target_send_reply(req, rc, info->mti_fail_id);
-        RETURN(0);
+       return next->md_ops->mdo_init_capa_ctxt(env, next,
+                                               m->mdt_lut.lut_mds_capa,
+                                               m->mdt_capa_timeout,
+                                               m->mdt_capa_alg,
+                                               m->mdt_capa_keys);
 }
 
 void mdt_lock_handle_init(struct mdt_lock_handle *lh)
@@ -2880,6 +2724,8 @@ void mdt_lock_handle_init(struct mdt_lock_handle *lh)
         lh->mlh_reg_mode = LCK_MINMODE;
         lh->mlh_pdo_lh.cookie = 0ull;
         lh->mlh_pdo_mode = LCK_MINMODE;
+       lh->mlh_rreg_lh.cookie = 0ull;
+       lh->mlh_rreg_mode = LCK_MINMODE;
 }
 
 void mdt_lock_handle_fini(struct mdt_lock_handle *lh)
@@ -2893,12 +2739,11 @@ void mdt_lock_handle_fini(struct mdt_lock_handle *lh)
  * uninitialized state, because it's too expensive to zero out whole
  * mdt_thread_info (> 1K) on each request arrival.
  */
-static void mdt_thread_info_init(struct ptlrpc_request *req,
-                                 struct mdt_thread_info *info)
+void mdt_thread_info_init(struct ptlrpc_request *req,
+                         struct mdt_thread_info *info)
 {
         int i;
 
-        req_capsule_init(&req->rq_pill, req, RCL_SERVER);
         info->mti_pill = &req->rq_pill;
 
         /* lock handle */
@@ -2911,13 +2756,12 @@ static void mdt_thread_info_init(struct ptlrpc_request *req,
                 info->mti_exp = req->rq_export;
         } else
                 info->mti_mdt = NULL;
-        info->mti_env = req->rq_svc_thread->t_env;
-        info->mti_fail_id = OBD_FAIL_MDS_ALL_REPLY_NET;
-        info->mti_transno = lustre_msg_get_transno(req->rq_reqmsg);
-        info->mti_mos = NULL;
+       info->mti_env = req->rq_svc_thread->t_env;
+       info->mti_transno = lustre_msg_get_transno(req->rq_reqmsg);
 
         memset(&info->mti_attr, 0, sizeof(info->mti_attr));
-        info->mti_body = NULL;
+       info->mti_big_buf = LU_BUF_NULL;
+       info->mti_body = NULL;
         info->mti_object = NULL;
         info->mti_dlm_req = NULL;
         info->mti_has_trans = 0;
@@ -2925,321 +2769,81 @@ static void mdt_thread_info_init(struct ptlrpc_request *req,
         info->mti_opdata = 0;
        info->mti_big_lmm_used = 0;
 
-        /* To not check for split by default. */
         info->mti_spec.no_create = 0;
-}
+       info->mti_spec.sp_rm_entry = 0;
 
-static void mdt_thread_info_fini(struct mdt_thread_info *info)
-{
-        int i;
-
-        req_capsule_fini(info->mti_pill);
-        if (info->mti_object != NULL) {
-                mdt_object_put(info->mti_env, info->mti_object);
-                info->mti_object = NULL;
-        }
-        for (i = 0; i < ARRAY_SIZE(info->mti_lh); i++)
-                mdt_lock_handle_fini(&info->mti_lh[i]);
-        info->mti_env = NULL;
+       info->mti_spec.u.sp_ea.eadata = NULL;
+       info->mti_spec.u.sp_ea.eadatalen = 0;
 }
 
-static int mdt_filter_recovery_request(struct ptlrpc_request *req,
-                                       struct obd_device *obd, int *process)
+void mdt_thread_info_fini(struct mdt_thread_info *info)
 {
-        switch (lustre_msg_get_opc(req->rq_reqmsg)) {
-        case MDS_CONNECT: /* This will never get here, but for completeness. */
-        case OST_CONNECT: /* This will never get here, but for completeness. */
-        case MDS_DISCONNECT:
-        case OST_DISCONNECT:
-       case OBD_IDX_READ:
-               *process = 1;
-               RETURN(0);
-
-        case MDS_CLOSE:
-        case MDS_DONE_WRITING:
-        case MDS_SYNC: /* used in unmounting */
-        case OBD_PING:
-        case MDS_REINT:
-        case SEQ_QUERY:
-        case FLD_QUERY:
-        case LDLM_ENQUEUE:
-                *process = target_queue_recovery_request(req, obd);
-                RETURN(0);
-
-        default:
-                DEBUG_REQ(D_ERROR, req, "not permitted during recovery");
-                *process = -EAGAIN;
-                RETURN(0);
-        }
-}
-
-/*
- * Handle recovery. Return:
- *        +1: continue request processing;
- *       -ve: abort immediately with the given error code;
- *         0: send reply with error code in req->rq_status;
- */
-static int mdt_recovery(struct mdt_thread_info *info)
-{
-        struct ptlrpc_request *req = mdt_info_req(info);
-        struct obd_device *obd;
-
-        ENTRY;
-
-        switch (lustre_msg_get_opc(req->rq_reqmsg)) {
-        case MDS_CONNECT:
-        case SEC_CTX_INIT:
-        case SEC_CTX_INIT_CONT:
-        case SEC_CTX_FINI:
-                {
-#if 0
-                        int rc;
-
-                        rc = mdt_handle_idmap(info);
-                        if (rc)
-                                RETURN(rc);
-                        else
-#endif
-                                RETURN(+1);
-                }
-        }
-
-        if (unlikely(!class_connected_export(req->rq_export))) {
-               CDEBUG(D_HA, "operation %d on unconnected MDS from %s\n",
-                      lustre_msg_get_opc(req->rq_reqmsg),
-                      libcfs_id2str(req->rq_peer));
-                /* FIXME: For CMD cleanup, when mds_B stop, the req from
-                 * mds_A will get -ENOTCONN(especially for ping req),
-                 * which will cause that mds_A deactive timeout, then when
-                 * mds_A cleanup, the cleanup process will be suspended since
-                 * deactive timeout is not zero.
-                 */
-                req->rq_status = -ENOTCONN;
-                target_send_reply(req, -ENOTCONN, info->mti_fail_id);
-                RETURN(0);
-        }
-
-        /* sanity check: if the xid matches, the request must be marked as a
-         * resent or replayed */
-        if (req_xid_is_last(req)) {
-                if (!(lustre_msg_get_flags(req->rq_reqmsg) &
-                      (MSG_RESENT | MSG_REPLAY))) {
-                        DEBUG_REQ(D_WARNING, req, "rq_xid "LPU64" matches last_xid, "
-                                  "expected REPLAY or RESENT flag (%x)", req->rq_xid,
-                                  lustre_msg_get_flags(req->rq_reqmsg));
-                        LBUG();
-                        req->rq_status = -ENOTCONN;
-                        RETURN(-ENOTCONN);
-                }
-        }
+       int i;
 
-        /* else: note the opposite is not always true; a RESENT req after a
-         * failover will usually not match the last_xid, since it was likely
-         * never committed. A REPLAYed request will almost never match the
-         * last xid, however it could for a committed, but still retained,
-         * open. */
-
-        obd = req->rq_export->exp_obd;
-
-        /* Check for aborted recovery... */
-        if (unlikely(obd->obd_recovering)) {
-                int rc;
-                int should_process;
-                DEBUG_REQ(D_INFO, req, "Got new replay");
-                rc = mdt_filter_recovery_request(req, obd, &should_process);
-                if (rc != 0 || !should_process)
-                        RETURN(rc);
-                else if (should_process < 0) {
-                        req->rq_status = should_process;
-                        rc = ptlrpc_error(req);
-                        RETURN(rc);
-                }
-        }
-        RETURN(+1);
-}
+       if (info->mti_object != NULL) {
+               mdt_object_put(info->mti_env, info->mti_object);
+               info->mti_object = NULL;
+       }
 
-static int mdt_msg_check_version(struct lustre_msg *msg)
-{
-        int rc;
+       for (i = 0; i < ARRAY_SIZE(info->mti_lh); i++)
+               mdt_lock_handle_fini(&info->mti_lh[i]);
+       info->mti_env = NULL;
+       info->mti_pill = NULL;
+       info->mti_exp = NULL;
 
-        switch (lustre_msg_get_opc(msg)) {
-        case MDS_CONNECT:
-        case MDS_DISCONNECT:
-        case OBD_PING:
-        case SEC_CTX_INIT:
-        case SEC_CTX_INIT_CONT:
-        case SEC_CTX_FINI:
-       case OBD_IDX_READ:
-                rc = lustre_msg_check_version(msg, LUSTRE_OBD_VERSION);
-                if (rc)
-                        CERROR("bad opc %u version %08x, expecting %08x\n",
-                               lustre_msg_get_opc(msg),
-                               lustre_msg_get_version(msg),
-                               LUSTRE_OBD_VERSION);
-                break;
-        case MDS_GETSTATUS:
-        case MDS_GETATTR:
-        case MDS_GETATTR_NAME:
-        case MDS_STATFS:
-        case MDS_READPAGE:
-        case MDS_WRITEPAGE:
-        case MDS_IS_SUBDIR:
-        case MDS_REINT:
-        case MDS_CLOSE:
-        case MDS_DONE_WRITING:
-        case MDS_PIN:
-        case MDS_SYNC:
-        case MDS_GETXATTR:
-        case MDS_SETXATTR:
-        case MDS_SET_INFO:
-        case MDS_GET_INFO:
-       case MDS_HSM_PROGRESS:
-       case MDS_HSM_REQUEST:
-       case MDS_HSM_CT_REGISTER:
-       case MDS_HSM_CT_UNREGISTER:
-       case MDS_HSM_STATE_GET:
-       case MDS_HSM_STATE_SET:
-       case MDS_HSM_ACTION:
-        case MDS_QUOTACHECK:
-        case MDS_QUOTACTL:
-       case UPDATE_OBJ:
-        case QUOTA_DQACQ:
-        case QUOTA_DQREL:
-        case SEQ_QUERY:
-        case FLD_QUERY:
-                rc = lustre_msg_check_version(msg, LUSTRE_MDS_VERSION);
-                if (rc)
-                        CERROR("bad opc %u version %08x, expecting %08x\n",
-                               lustre_msg_get_opc(msg),
-                               lustre_msg_get_version(msg),
-                               LUSTRE_MDS_VERSION);
-                break;
-        case LDLM_ENQUEUE:
-        case LDLM_CONVERT:
-        case LDLM_BL_CALLBACK:
-        case LDLM_CP_CALLBACK:
-                rc = lustre_msg_check_version(msg, LUSTRE_DLM_VERSION);
-                if (rc)
-                        CERROR("bad opc %u version %08x, expecting %08x\n",
-                               lustre_msg_get_opc(msg),
-                               lustre_msg_get_version(msg),
-                               LUSTRE_DLM_VERSION);
-                break;
-        case OBD_LOG_CANCEL:
-        case LLOG_ORIGIN_HANDLE_CREATE:
-        case LLOG_ORIGIN_HANDLE_NEXT_BLOCK:
-        case LLOG_ORIGIN_HANDLE_READ_HEADER:
-        case LLOG_ORIGIN_HANDLE_CLOSE:
-        case LLOG_ORIGIN_HANDLE_DESTROY:
-        case LLOG_ORIGIN_HANDLE_PREV_BLOCK:
-        case LLOG_CATINFO:
-                rc = lustre_msg_check_version(msg, LUSTRE_LOG_VERSION);
-                if (rc)
-                        CERROR("bad opc %u version %08x, expecting %08x\n",
-                               lustre_msg_get_opc(msg),
-                               lustre_msg_get_version(msg),
-                               LUSTRE_LOG_VERSION);
-                break;
-        default:
-                CERROR("MDS unknown opcode %d\n", lustre_msg_get_opc(msg));
-                rc = -ENOTSUPP;
-        }
-        return rc;
+       if (unlikely(info->mti_big_buf.lb_buf != NULL))
+               lu_buf_free(&info->mti_big_buf);
 }
 
-static int mdt_handle0(struct ptlrpc_request *req,
-                       struct mdt_thread_info *info,
-                       struct mdt_opc_slice *supported)
+struct mdt_thread_info *tsi2mdt_info(struct tgt_session_info *tsi)
 {
-        struct mdt_handler *h;
-        struct lustre_msg  *msg;
-        int                 rc;
+       struct mdt_thread_info  *mti;
+       struct lustre_capa      *lc;
 
-        ENTRY;
+       mti = mdt_th_info(tsi->tsi_env);
+       LASSERT(mti != NULL);
 
-        if (OBD_FAIL_CHECK_ORSET(OBD_FAIL_MDS_ALL_REQUEST_NET, OBD_FAIL_ONCE))
-                RETURN(0);
+       mdt_thread_info_init(tgt_ses_req(tsi), mti);
+       if (tsi->tsi_corpus != NULL) {
+               struct req_capsule *pill = tsi->tsi_pill;
 
-        LASSERT(current->journal_info == NULL);
-
-        msg = req->rq_reqmsg;
-        rc = mdt_msg_check_version(msg);
-        if (likely(rc == 0)) {
-                rc = mdt_recovery(info);
-                if (likely(rc == +1)) {
-                        h = mdt_handler_find(lustre_msg_get_opc(msg),
-                                             supported);
-                        if (likely(h != NULL)) {
-                                rc = mdt_req_handle(info, h, req);
-                        } else {
-                                CERROR("The unsupported opc: 0x%x\n",
-                                       lustre_msg_get_opc(msg) );
-                                req->rq_status = -ENOTSUPP;
-                                rc = ptlrpc_error(req);
-                                RETURN(rc);
-                        }
-                }
-        } else
-                CERROR(LUSTRE_MDT_NAME" drops mal-formed request\n");
-        RETURN(rc);
-}
+               mti->mti_object = mdt_obj(tsi->tsi_corpus);
+               lu_object_get(tsi->tsi_corpus);
 
-/*
- * MDT handler function called by ptlrpc service thread when request comes.
- *
- * XXX common "target" functionality should be factored into separate module
- * shared by mdt, ost and stand-alone services like fld.
- */
-int mdt_handle_common(struct ptlrpc_request *req,
-                     struct mdt_opc_slice *supported)
-{
-        struct lu_env          *env;
-        struct mdt_thread_info *info;
-        int                     rc;
-        ENTRY;
-
-        env = req->rq_svc_thread->t_env;
-       /* Refill(initilize) the context(mdt_thread_info), in case it is
-        * not initialized yet. Usually it happens during start up, after
-        * MDS(ptlrpc threads) is start up, it gets the first CONNECT request,
-        * before MDT_thread_info is initialized */
-       lu_env_refill(env);
-        LASSERT(env != NULL);
-        LASSERT(env->le_ses != NULL);
-        LASSERT(env->le_ctx.lc_thread == req->rq_svc_thread);
-        info = lu_context_key_get(&env->le_ctx, &mdt_thread_key);
-        LASSERT(info != NULL);
-
-        mdt_thread_info_init(req, info);
-
-        rc = mdt_handle0(req, info, supported);
+               /*
+                * XXX: must be part of tgt_mdt_body_unpack but moved here
+                * due to mdt_set_capainfo().
+                */
+               if (req_capsule_has_field(pill, &RMF_CAPA1, RCL_CLIENT) &&
+                   req_capsule_get_size(pill, &RMF_CAPA1, RCL_CLIENT) > 0) {
+                       lc = req_capsule_client_get(pill, &RMF_CAPA1);
+                       mdt_set_capainfo(mti, 0, &tsi->tsi_mdt_body->fid1, lc);
+               }
+       }
+       mti->mti_body = tsi->tsi_mdt_body;
+       mti->mti_dlm_req = tsi->tsi_dlm_req;
 
-        mdt_thread_info_fini(info);
-        RETURN(rc);
+       return mti;
 }
 
-/*
- * This is called from recovery code as handler of _all_ RPC types, FLD and SEQ
- * as well.
- */
-int mdt_recovery_handle(struct ptlrpc_request *req)
+int mdt_tgt_connect(struct tgt_session_info *tsi)
 {
-        int rc;
-        ENTRY;
+       struct ptlrpc_request   *req = tgt_ses_req(tsi);
+       int                      rc;
 
-        switch (lustre_msg_get_opc(req->rq_reqmsg)) {
-        case FLD_QUERY:
-                rc = mdt_handle_common(req, mdt_fld_handlers);
-                break;
-        case SEQ_QUERY:
-                rc = mdt_handle_common(req, mdt_seq_handlers);
-                break;
-        default:
-                rc = mdt_handle_common(req, mdt_regular_handlers);
-                break;
-        }
+       ENTRY;
 
-        RETURN(rc);
+       rc = tgt_connect(tsi);
+       if (rc != 0)
+               RETURN(rc);
+
+       rc = mdt_init_idmap(tsi);
+       if (rc != 0)
+               GOTO(err, rc);
+       RETURN(0);
+err:
+       obd_disconnect(class_export_get(req->rq_export));
+       return rc;
 }
 
 enum mdt_it_code {
@@ -3261,6 +2865,12 @@ static int mdt_intent_getattr(enum mdt_it_code opcode,
                               struct mdt_thread_info *info,
                               struct ldlm_lock **,
                              __u64);
+
+static int mdt_intent_getxattr(enum mdt_it_code opcode,
+                               struct mdt_thread_info *info,
+                               struct ldlm_lock **lockp,
+                               __u64 flags);
+
 static int mdt_intent_layout(enum mdt_it_code opcode,
                             struct mdt_thread_info *info,
                             struct ldlm_lock **,
@@ -3288,7 +2898,14 @@ static struct mdt_it_flavor {
         },
         [MDT_IT_OCREAT]   = {
                 .it_fmt   = &RQF_LDLM_INTENT,
-                .it_flags = MUTABOR,
+               /*
+                * OCREAT is not a MUTABOR request as if the file
+                * already exists.
+                * We do the extra check of OBD_CONNECT_RDONLY in
+                * mdt_reint_open() when we really need to create
+                * the object.
+                */
+               .it_flags = 0,
                 .it_act   = mdt_intent_reint,
                 .it_reint = REINT_OPEN
         },
@@ -3325,9 +2942,9 @@ static struct mdt_it_flavor {
                 .it_act   = NULL
         },
         [MDT_IT_GETXATTR] = {
-                .it_fmt   = NULL,
-                .it_flags = 0,
-                .it_act   = NULL
+               .it_fmt   = &RQF_LDLM_INTENT_GETXATTR,
+               .it_flags = HABEO_CORPUS,
+               .it_act   = mdt_intent_getxattr
         },
        [MDT_IT_LAYOUT] = {
                .it_fmt   = &RQF_LDLM_INTENT_LAYOUT,
@@ -3422,9 +3039,10 @@ int mdt_intent_lock_replace(struct mdt_thread_info *info,
 }
 
 static void mdt_intent_fixup_resent(struct mdt_thread_info *info,
-                                    struct ldlm_lock *new_lock,
-                                    struct ldlm_lock **old_lock,
-                                    struct mdt_lock_handle *lh)
+                                   struct ldlm_lock *new_lock,
+                                   struct ldlm_lock **old_lock,
+                                   struct mdt_lock_handle *lh,
+                                   enum mdt_it_code opcode)
 {
         struct ptlrpc_request  *req = mdt_info_req(info);
         struct obd_export      *exp = req->rq_export;
@@ -3437,29 +3055,37 @@ static void mdt_intent_fixup_resent(struct mdt_thread_info *info,
 
         dlmreq = req_capsule_client_get(info->mti_pill, &RMF_DLM_REQ);
         remote_hdl = dlmreq->lock_handle[0];
-
-       /* In the function below, .hs_keycmp resolves to
-        * ldlm_export_lock_keycmp() */
-       /* coverity[overrun-buffer-val] */
-        lock = cfs_hash_lookup(exp->exp_lock_hash, &remote_hdl);
-        if (lock) {
-                if (lock != new_lock) {
-                        lh->mlh_reg_lh.cookie = lock->l_handle.h_cookie;
-                        lh->mlh_reg_mode = lock->l_granted_mode;
-
-                        LDLM_DEBUG(lock, "Restoring lock cookie");
-                        DEBUG_REQ(D_DLMTRACE, req,
-                                  "restoring lock cookie "LPX64,
-                                  lh->mlh_reg_lh.cookie);
-                        if (old_lock)
-                                *old_lock = LDLM_LOCK_GET(lock);
-                        cfs_hash_put(exp->exp_lock_hash, &lock->l_exp_hash);
-                        return;
-                }
-
-                cfs_hash_put(exp->exp_lock_hash, &lock->l_exp_hash);
-        }
-
+       /* If the client does not require open lock, it does not need to
+        * search lock in exp_lock_hash, since the server thread will
+        * make sure the lock will be released, and the resend request
+        * can always re-enqueue the lock */
+       if ((opcode != MDT_IT_OPEN) || (opcode == MDT_IT_OPEN &&
+           info->mti_spec.sp_cr_flags & MDS_OPEN_LOCK)) {
+               /* In the function below, .hs_keycmp resolves to
+                * ldlm_export_lock_keycmp() */
+               /* coverity[overrun-buffer-val] */
+               lock = cfs_hash_lookup(exp->exp_lock_hash, &remote_hdl);
+               if (lock) {
+                       lock_res_and_lock(lock);
+                       if (lock != new_lock) {
+                               lh->mlh_reg_lh.cookie = lock->l_handle.h_cookie;
+                               lh->mlh_reg_mode = lock->l_granted_mode;
+
+                               LDLM_DEBUG(lock, "Restoring lock cookie");
+                               DEBUG_REQ(D_DLMTRACE, req,
+                                         "restoring lock cookie "LPX64,
+                                         lh->mlh_reg_lh.cookie);
+                               if (old_lock)
+                                       *old_lock = LDLM_LOCK_GET(lock);
+                               cfs_hash_put(exp->exp_lock_hash,
+                                            &lock->l_exp_hash);
+                               unlock_res_and_lock(lock);
+                               return;
+                       }
+                       cfs_hash_put(exp->exp_lock_hash, &lock->l_exp_hash);
+                       unlock_res_and_lock(lock);
+               }
+       }
         /*
          * If the xid matches, then we know this is a resent request, and allow
          * it. (It's probably an OPEN, for which we don't send a lock.
@@ -3478,6 +3104,44 @@ static void mdt_intent_fixup_resent(struct mdt_thread_info *info,
                   remote_hdl.cookie);
 }
 
+static int mdt_intent_getxattr(enum mdt_it_code opcode,
+                               struct mdt_thread_info *info,
+                               struct ldlm_lock **lockp,
+                               __u64 flags)
+{
+       struct mdt_lock_handle *lhc = &info->mti_lh[MDT_LH_RMT];
+       struct ldlm_reply      *ldlm_rep = NULL;
+       int rc, grc;
+
+       /*
+        * Initialize lhc->mlh_reg_lh either from a previously granted lock
+        * (for the resend case) or a new lock. Below we will use it to
+        * replace the original lock.
+        */
+       mdt_intent_fixup_resent(info, *lockp, NULL, lhc, opcode);
+       if (!lustre_handle_is_used(&lhc->mlh_reg_lh)) {
+               mdt_lock_reg_init(lhc, (*lockp)->l_req_mode);
+               rc = mdt_object_lock(info, info->mti_object, lhc,
+                                       MDS_INODELOCK_XATTR,
+                                       MDT_LOCAL_LOCK);
+               if (rc)
+                       return rc;
+       }
+
+       grc = mdt_getxattr(info);
+
+       rc = mdt_intent_lock_replace(info, lockp, NULL, lhc, flags);
+
+       if (mdt_info_req(info)->rq_repmsg != NULL)
+               ldlm_rep = req_capsule_server_get(info->mti_pill, &RMF_DLM_REP);
+       if (ldlm_rep == NULL)
+               RETURN(err_serious(-EFAULT));
+
+       ldlm_rep->lock_policy_res2 = grc;
+
+       return rc;
+}
+
 static int mdt_intent_getattr(enum mdt_it_code opcode,
                               struct mdt_thread_info *info,
                               struct ldlm_lock **lockp,
@@ -3505,10 +3169,11 @@ static int mdt_intent_getattr(enum mdt_it_code opcode,
 
         switch (opcode) {
         case MDT_IT_LOOKUP:
-                child_bits = MDS_INODELOCK_LOOKUP;
+               child_bits = MDS_INODELOCK_LOOKUP | MDS_INODELOCK_PERM;
                 break;
         case MDT_IT_GETATTR:
-                child_bits = MDS_INODELOCK_LOOKUP | MDS_INODELOCK_UPDATE;
+               child_bits = MDS_INODELOCK_LOOKUP | MDS_INODELOCK_UPDATE |
+                            MDS_INODELOCK_PERM;
                 break;
         default:
                 CERROR("Unsupported intent (%d)\n", opcode);
@@ -3523,11 +3188,11 @@ static int mdt_intent_getattr(enum mdt_it_code opcode,
         ldlm_rep = req_capsule_server_get(info->mti_pill, &RMF_DLM_REP);
         mdt_set_disposition(info, ldlm_rep, DISP_IT_EXECD);
 
-        /* Get lock from request for possible resent case. */
-        mdt_intent_fixup_resent(info, *lockp, &new_lock, lhc);
+       /* Get lock from request for possible resent case. */
+       mdt_intent_fixup_resent(info, *lockp, &new_lock, lhc, opcode);
 
-        ldlm_rep->lock_policy_res2 =
-                mdt_getattr_name_lock(info, lhc, child_bits, ldlm_rep);
+       rc = mdt_getattr_name_lock(info, lhc, child_bits, ldlm_rep);
+       ldlm_rep->lock_policy_res2 = clear_serious(rc);
 
         if (mdt_get_disposition(ldlm_rep, DISP_LOOKUP_NEG))
                 ldlm_rep->lock_policy_res2 = 0;
@@ -3555,15 +3220,38 @@ static int mdt_intent_layout(enum mdt_it_code opcode,
                             __u64 flags)
 {
        struct layout_intent *layout;
+       struct lu_fid *fid;
+       struct mdt_object *obj = NULL;
+       struct md_object *child = NULL;
        int rc;
        ENTRY;
 
        if (opcode != MDT_IT_LAYOUT) {
-               CERROR("%s: Unknown intent (%d)\n",
-                       info->mti_exp->exp_obd->obd_name, opcode);
+               CERROR("%s: Unknown intent (%d)\n", mdt_obd_name(info->mti_mdt),
+                       opcode);
                RETURN(-EINVAL);
        }
 
+       fid = &info->mti_tmp_fid2;
+       fid_extract_from_res_name(fid, &(*lockp)->l_resource->lr_name);
+
+       obj = mdt_object_find(info->mti_env, info->mti_mdt, fid);
+       if (IS_ERR(obj))
+               RETURN(PTR_ERR(obj));
+
+       if (mdt_object_exists(obj) && !mdt_object_remote(obj)) {
+               child = mdt_object_child(obj);
+
+               /* get the length of lsm */
+               rc = mo_xattr_get(info->mti_env, child, &LU_BUF_NULL,
+                                 XATTR_NAME_LOV);
+
+               if (rc > info->mti_mdt->mdt_max_mdsize)
+                       info->mti_mdt->mdt_max_mdsize = rc;
+       }
+
+       mdt_object_put(info->mti_env, obj);
+
        (*lockp)->l_lvb_type = LVB_T_LAYOUT;
        req_capsule_set_size(info->mti_pill, &RMF_DLM_LVB, RCL_SERVER,
                        ldlm_lvbo_size(*lockp));
@@ -3578,7 +3266,7 @@ static int mdt_intent_layout(enum mdt_it_code opcode,
                RETURN(0);
 
        CERROR("%s: Unsupported layout intent (%d)\n",
-               info->mti_exp->exp_obd->obd_name, layout->li_opc);
+               mdt_obd_name(info->mti_mdt), layout->li_opc);
        RETURN(-EINVAL);
 }
 
@@ -3599,7 +3287,7 @@ static int mdt_intent_reint(enum mdt_it_code opcode,
 
         ENTRY;
 
-        opc = mdt_reint_opcode(info, intent_fmts);
+       opc = mdt_reint_opcode(mdt_info_req(info), intent_fmts);
         if (opc < 0)
                 RETURN(opc);
 
@@ -3609,8 +3297,8 @@ static int mdt_intent_reint(enum mdt_it_code opcode,
                 RETURN(err_serious(-EPROTO));
         }
 
-        /* Get lock from request for possible resent case. */
-        mdt_intent_fixup_resent(info, *lockp, NULL, lhc);
+       /* Get lock from request for possible resent case. */
+       mdt_intent_fixup_resent(info, *lockp, NULL, lhc, opcode);
 
         rc = mdt_reint_internal(info, lhc, opc);
 
@@ -3624,14 +3312,16 @@ static int mdt_intent_reint(enum mdt_it_code opcode,
         if (rc != 0)
                 mdt_set_disposition(info, rep, DISP_LOOKUP_EXECD);
 
-        /* Cross-ref case, the lock should be returned to the client */
-        if (rc == -EREMOTE) {
-                LASSERT(lustre_handle_is_used(&lhc->mlh_reg_lh));
-                rep->lock_policy_res2 = 0;
-                rc = mdt_intent_lock_replace(info, lockp, NULL, lhc, flags);
-                RETURN(rc);
-        }
-        rep->lock_policy_res2 = clear_serious(rc);
+       /* the open lock or the lock for cross-ref object should be
+        * returned to the client */
+       if (rc == -EREMOTE || mdt_get_disposition(rep, DISP_OPEN_LOCK)) {
+               LASSERT(lustre_handle_is_used(&lhc->mlh_reg_lh));
+               rep->lock_policy_res2 = 0;
+               rc = mdt_intent_lock_replace(info, lockp, NULL, lhc, flags);
+               RETURN(rc);
+       }
+
+       rep->lock_policy_res2 = clear_serious(rc);
 
         if (rep->lock_policy_res2 == -ENOENT &&
             mdt_get_disposition(rep, DISP_LOOKUP_NEG))
@@ -3752,35 +3442,47 @@ static int mdt_intent_opc(long itopc, struct mdt_thread_info *info,
         rc = mdt_unpack_req_pack_rep(info, flv->it_flags);
         if (rc == 0) {
                 struct ptlrpc_request *req = mdt_info_req(info);
-                if (flv->it_flags & MUTABOR &&
-                    req->rq_export->exp_connect_flags & OBD_CONNECT_RDONLY)
-                        RETURN(-EROFS);
+               if (flv->it_flags & MUTABOR &&
+                   exp_connect_flags(req->rq_export) & OBD_CONNECT_RDONLY)
+                       RETURN(-EROFS);
         }
         if (rc == 0 && flv->it_act != NULL) {
-                /* execute policy */
-                rc = flv->it_act(opc, info, lockp, flags);
-        } else {
-                rc = -EOPNOTSUPP;
-        }
-        RETURN(rc);
+               struct ldlm_reply *rep;
+
+               /* execute policy */
+               rc = flv->it_act(opc, info, lockp, flags);
+
+               /* Check whether the reply has been packed successfully. */
+               if (mdt_info_req(info)->rq_repmsg != NULL) {
+                       rep = req_capsule_server_get(info->mti_pill,
+                                                    &RMF_DLM_REP);
+                       rep->lock_policy_res2 =
+                               ptlrpc_status_hton(rep->lock_policy_res2);
+               }
+       } else {
+               rc = -EPROTO;
+       }
+       RETURN(rc);
 }
 
 static int mdt_intent_policy(struct ldlm_namespace *ns,
                              struct ldlm_lock **lockp, void *req_cookie,
                             ldlm_mode_t mode, __u64 flags, void *data)
 {
-        struct mdt_thread_info *info;
-        struct ptlrpc_request  *req  =  req_cookie;
-        struct ldlm_intent     *it;
-        struct req_capsule     *pill;
-        int rc;
+       struct tgt_session_info *tsi;
+       struct mdt_thread_info  *info;
+       struct ptlrpc_request   *req  =  req_cookie;
+       struct ldlm_intent      *it;
+       struct req_capsule      *pill;
+       int rc;
 
-        ENTRY;
+       ENTRY;
+
+       LASSERT(req != NULL);
 
-        LASSERT(req != NULL);
+       tsi = tgt_ses_info(req->rq_svc_thread->t_env);
 
-        info = lu_context_key_get(&req->rq_svc_thread->t_env->le_ctx,
-                                  &mdt_thread_key);
+       info = tsi2mdt_info(tsi);
         LASSERT(info != NULL);
         pill = info->mti_pill;
         LASSERT(pill->rc_req == req);
@@ -3812,100 +3514,205 @@ static int mdt_intent_policy(struct ldlm_namespace *ns,
                 if (rc)
                         rc = err_serious(rc);
         }
-        RETURN(rc);
+       mdt_thread_info_fini(info);
+       RETURN(rc);
 }
 
-static int mdt_seq_fini(const struct lu_env *env,
-                        struct mdt_device *m)
+static void mdt_deregister_seq_exp(struct mdt_device *mdt)
 {
-       return seq_site_fini(env, mdt_seq_site(m));
+       struct seq_server_site  *ss = mdt_seq_site(mdt);
+
+       if (ss->ss_node_id == 0)
+               return;
+
+       if (ss->ss_client_seq != NULL) {
+               lustre_deregister_lwp_item(&ss->ss_client_seq->lcs_exp);
+               ss->ss_client_seq->lcs_exp = NULL;
+       }
+
+       if (ss->ss_server_fld != NULL) {
+               lustre_deregister_lwp_item(&ss->ss_server_fld->lsf_control_exp);
+               ss->ss_server_fld->lsf_control_exp = NULL;
+       }
 }
 
-static int mdt_seq_init(const struct lu_env *env,
-                        const char *uuid,
-                        struct mdt_device *m)
+static void mdt_seq_fini_cli(struct mdt_device *mdt)
 {
-       struct seq_server_site *ss;
-       char *prefix;
-       int rc;
+       struct seq_server_site *ss = mdt_seq_site(mdt);
+
+       if (ss == NULL)
+               return;
+
+       if (ss->ss_server_seq == NULL)
+               seq_server_set_cli(NULL, ss->ss_server_seq, NULL);
+
+       return;
+}
+
+static int mdt_seq_fini(const struct lu_env *env, struct mdt_device *mdt)
+{
+       mdt_seq_fini_cli(mdt);
+       mdt_deregister_seq_exp(mdt);
+
+       return seq_site_fini(env, mdt_seq_site(mdt));
+}
+
+/**
+ * It will retrieve its FLDB entries from MDT0, and it only happens
+ * when upgrading existent FS to 2.6 or when local FLDB is corrupted,
+ * and it needs to refresh FLDB from the MDT0.
+ **/
+static int mdt_register_lwp_callback(void *data)
+{
+       struct lu_env           env;
+       struct mdt_device       *mdt = data;
+       struct lu_server_fld    *fld = mdt_seq_site(mdt)->ss_server_fld;
+       int                     rc;
        ENTRY;
 
-       ss = mdt_seq_site(m);
+       LASSERT(mdt_seq_site(mdt)->ss_node_id != 0);
 
-       /*
-        * This is sequence-controller node. Init seq-controller server on local
-        * MDT.
-        */
-       if (ss->ss_node_id == 0) {
-               LASSERT(ss->ss_control_seq == NULL);
+       if (!likely(fld->lsf_new))
+               RETURN(0);
 
-               OBD_ALLOC_PTR(ss->ss_control_seq);
-               if (ss->ss_control_seq == NULL)
-                       RETURN(-ENOMEM);
+       rc = lu_env_init(&env, LCT_MD_THREAD);
+       if (rc) {
+               CERROR("%s: cannot init env: rc = %d\n", mdt_obd_name(mdt), rc);
+               RETURN(rc);
+       }
+
+       rc = fld_update_from_controller(&env, fld);
+       if (rc != 0) {
+               CERROR("%s: cannot update controller: rc = %d\n",
+                      mdt_obd_name(mdt), rc);
+               GOTO(out, rc);
+       }
+out:
+       lu_env_fini(&env);
+       RETURN(rc);
+}
 
-               rc = seq_server_init(ss->ss_control_seq,
-                                    m->mdt_bottom, uuid,
-                                    LUSTRE_SEQ_CONTROLLER,
-                                    ss,
-                                    env);
+static int mdt_register_seq_exp(struct mdt_device *mdt)
+{
+       struct seq_server_site  *ss = mdt_seq_site(mdt);
+       char                    *lwp_name = NULL;
+       int                     rc;
 
-               if (rc)
-                       GOTO(out_seq_fini, rc);
+       if (ss->ss_node_id == 0)
+               return 0;
 
-               OBD_ALLOC_PTR(ss->ss_client_seq);
-               if (ss->ss_client_seq == NULL)
-                       GOTO(out_seq_fini, rc = -ENOMEM);
+       OBD_ALLOC(lwp_name, MAX_OBD_NAME);
+       if (lwp_name == NULL)
+               GOTO(out_free, rc = -ENOMEM);
 
-               OBD_ALLOC(prefix, MAX_OBD_NAME + 5);
-               if (prefix == NULL) {
-                       OBD_FREE_PTR(ss->ss_client_seq);
-                       GOTO(out_seq_fini, rc = -ENOMEM);
-               }
+       rc = tgt_name2lwp_name(mdt_obd_name(mdt), lwp_name, MAX_OBD_NAME, 0);
+       if (rc != 0)
+               GOTO(out_free, rc);
 
-               snprintf(prefix, MAX_OBD_NAME + 5, "ctl-%s",
-                        uuid);
+       rc = lustre_register_lwp_item(lwp_name, &ss->ss_client_seq->lcs_exp,
+                                     NULL, NULL);
+       if (rc != 0)
+               GOTO(out_free, rc);
 
-               /*
-                * Init seq-controller client after seq-controller server is
-                * ready. Pass ss->ss_control_seq to it for direct talking.
-                */
-               rc = seq_client_init(ss->ss_client_seq, NULL,
-                                    LUSTRE_SEQ_METADATA, prefix,
-                                    ss->ss_control_seq);
-               OBD_FREE(prefix, MAX_OBD_NAME + 5);
+       rc = lustre_register_lwp_item(lwp_name,
+                                     &ss->ss_server_fld->lsf_control_exp,
+                                     mdt_register_lwp_callback, mdt);
+       if (rc != 0) {
+               lustre_deregister_lwp_item(&ss->ss_client_seq->lcs_exp);
+               ss->ss_client_seq->lcs_exp = NULL;
+               GOTO(out_free, rc);
+       }
+out_free:
+       if (lwp_name != NULL)
+               OBD_FREE(lwp_name, MAX_OBD_NAME);
+
+       return rc;
+}
+
+/*
+ * Init client sequence manager which is used by local MDS to talk to sequence
+ * controller on remote node.
+ */
+static int mdt_seq_init_cli(const struct lu_env *env, struct mdt_device *mdt)
+{
+       struct seq_server_site  *ss = mdt_seq_site(mdt);
+       int                     rc;
+       char                    *prefix;
+       ENTRY;
+
+       /* check if this is adding the first MDC and controller is not yet
+        * initialized. */
+       OBD_ALLOC_PTR(ss->ss_client_seq);
+       if (ss->ss_client_seq == NULL)
+               RETURN(-ENOMEM);
+
+       OBD_ALLOC(prefix, MAX_OBD_NAME + 5);
+       if (prefix == NULL) {
+               OBD_FREE_PTR(ss->ss_client_seq);
+               ss->ss_client_seq = NULL;
+               RETURN(-ENOMEM);
+       }
+
+       /* Note: seq_client_fini will be called in seq_site_fini */
+       snprintf(prefix, MAX_OBD_NAME + 5, "ctl-%s", mdt_obd_name(mdt));
+       rc = seq_client_init(ss->ss_client_seq, NULL, LUSTRE_SEQ_METADATA,
+                            prefix, ss->ss_node_id == 0 ?  ss->ss_control_seq :
+                                                           NULL);
+       OBD_FREE(prefix, MAX_OBD_NAME + 5);
+       if (rc != 0) {
+               OBD_FREE_PTR(ss->ss_client_seq);
+               ss->ss_client_seq = NULL;
+               RETURN(rc);
+       }
+
+       rc = seq_server_set_cli(env, ss->ss_server_seq, ss->ss_client_seq);
+
+       RETURN(rc);
+}
+
+static int mdt_seq_init(const struct lu_env *env, struct mdt_device *mdt)
+{
+       struct seq_server_site  *ss;
+       int                     rc;
+       ENTRY;
+
+       ss = mdt_seq_site(mdt);
+       /* init sequence controller server(MDT0) */
+       if (ss->ss_node_id == 0) {
+               OBD_ALLOC_PTR(ss->ss_control_seq);
+               if (ss->ss_control_seq == NULL)
+                       RETURN(-ENOMEM);
 
+               rc = seq_server_init(env, ss->ss_control_seq, mdt->mdt_bottom,
+                                    mdt_obd_name(mdt), LUSTRE_SEQ_CONTROLLER,
+                                    ss);
                if (rc)
                        GOTO(out_seq_fini, rc);
        }
 
-       /* Init seq-server on local MDT */
-       LASSERT(ss->ss_server_seq == NULL);
-
+       /* Init normal sequence server */
        OBD_ALLOC_PTR(ss->ss_server_seq);
        if (ss->ss_server_seq == NULL)
                GOTO(out_seq_fini, rc = -ENOMEM);
 
-       rc = seq_server_init(ss->ss_server_seq,
-                            m->mdt_bottom, uuid,
-                            LUSTRE_SEQ_SERVER,
-                            ss,
-                            env);
+       rc = seq_server_init(env, ss->ss_server_seq, mdt->mdt_bottom,
+                            mdt_obd_name(mdt), LUSTRE_SEQ_SERVER, ss);
        if (rc)
-               GOTO(out_seq_fini, rc = -ENOMEM);
+               GOTO(out_seq_fini, rc);
 
-       /* Assign seq-controller client to local seq-server. */
-       if (ss->ss_node_id == 0) {
-               LASSERT(ss->ss_client_seq != NULL);
+       /* init seq client for seq server to talk to seq controller(MDT0) */
+       rc = mdt_seq_init_cli(env, mdt);
+       if (rc != 0)
+               GOTO(out_seq_fini, rc);
 
-               rc = seq_server_set_cli(ss->ss_server_seq,
-                                       ss->ss_client_seq,
-                                       env);
-       }
+       if (ss->ss_node_id != 0)
+               /* register controler export through lwp */
+               rc = mdt_register_seq_exp(mdt);
 
        EXIT;
 out_seq_fini:
        if (rc)
-               mdt_seq_fini(env, m);
+               mdt_seq_fini(env, mdt);
 
        return rc;
 }
@@ -3943,7 +3750,7 @@ static int mdt_fld_init(const struct lu_env *env,
                RETURN(rc = -ENOMEM);
 
        rc = fld_server_init(env, ss->ss_server_fld, m->mdt_bottom, uuid,
-                            ss->ss_node_id, LU_SEQ_RANGE_MDT);
+                            LU_SEQ_RANGE_MDT);
        if (rc) {
                OBD_FREE_PTR(ss->ss_server_fld);
                ss->ss_server_fld = NULL;
@@ -3956,7 +3763,7 @@ static int mdt_fld_init(const struct lu_env *env,
 static void mdt_stack_pre_fini(const struct lu_env *env,
                           struct mdt_device *m, struct lu_device *top)
 {
-       struct obd_device       *obd = mdt2obd_dev(m);
+       struct obd_device       *obd;
        struct lustre_cfg_bufs  *bufs;
        struct lustre_cfg       *lcfg;
        struct mdt_thread_info  *info;
@@ -3978,7 +3785,7 @@ static void mdt_stack_pre_fini(const struct lu_env *env,
         * objects (some of them are pinned by osd, for example *
         * the proper solution should be a model where object used
         * by osd only doesn't have mdt/mdd slices -bzzz */
-       lustre_cfg_bufs_reset(bufs, obd->obd_name);
+       lustre_cfg_bufs_reset(bufs, mdt_obd_name(m));
        lustre_cfg_bufs_set_string(bufs, 1, NULL);
        lcfg = lustre_cfg_new(LCFG_PRE_CLEANUP, bufs);
        if (!lcfg) {
@@ -3991,44 +3798,44 @@ static void mdt_stack_pre_fini(const struct lu_env *env,
 }
 
 static void mdt_stack_fini(const struct lu_env *env,
-                           struct mdt_device *m, struct lu_device *top)
+                          struct mdt_device *m, struct lu_device *top)
 {
-        struct obd_device       *obd = mdt2obd_dev(m);
-        struct lustre_cfg_bufs  *bufs;
-        struct lustre_cfg       *lcfg;
-        struct mdt_thread_info  *info;
-        char flags[3]="";
-        ENTRY;
+       struct obd_device       *obd = mdt2obd_dev(m);
+       struct lustre_cfg_bufs  *bufs;
+       struct lustre_cfg       *lcfg;
+       struct mdt_thread_info  *info;
+       char                     flags[3] = "";
+       ENTRY;
 
-        info = lu_context_key_get(&env->le_ctx, &mdt_thread_key);
-        LASSERT(info != NULL);
+       info = lu_context_key_get(&env->le_ctx, &mdt_thread_key);
+       LASSERT(info != NULL);
 
        lu_dev_del_linkage(top->ld_site, top);
 
        lu_site_purge(env, top->ld_site, -1);
 
-        bufs = &info->mti_u.bufs;
-        /* process cleanup, pass mdt obd name to get obd umount flags */
+       bufs = &info->mti_u.bufs;
+       /* process cleanup, pass mdt obd name to get obd umount flags */
        /* another purpose is to let all layers to release their objects */
-        lustre_cfg_bufs_reset(bufs, obd->obd_name);
-        if (obd->obd_force)
-                strcat(flags, "F");
-        if (obd->obd_fail)
-                strcat(flags, "A");
-        lustre_cfg_bufs_set_string(bufs, 1, flags);
-        lcfg = lustre_cfg_new(LCFG_CLEANUP, bufs);
-        if (!lcfg) {
-                CERROR("Cannot alloc lcfg!\n");
-                return;
-        }
-        LASSERT(top);
-        top->ld_ops->ldo_process_config(env, top, lcfg);
-        lustre_cfg_free(lcfg);
+       lustre_cfg_bufs_reset(bufs, mdt_obd_name(m));
+       if (obd->obd_force)
+               strcat(flags, "F");
+       if (obd->obd_fail)
+               strcat(flags, "A");
+       lustre_cfg_bufs_set_string(bufs, 1, flags);
+       lcfg = lustre_cfg_new(LCFG_CLEANUP, bufs);
+       if (!lcfg) {
+               CERROR("Cannot alloc lcfg!\n");
+               return;
+       }
+       LASSERT(top);
+       top->ld_ops->ldo_process_config(env, top, lcfg);
+       lustre_cfg_free(lcfg);
 
        lu_site_purge(env, top->ld_site, -1);
 
-        m->mdt_child = NULL;
-        m->mdt_bottom = NULL;
+       m->mdt_child = NULL;
+       m->mdt_bottom = NULL;
 
        obd_disconnect(m->mdt_child_exp);
        m->mdt_child_exp = NULL;
@@ -4052,7 +3859,7 @@ static int mdt_connect_to_next(const struct lu_env *env, struct mdt_device *m,
        obd = class_name2obd(next);
        if (obd == NULL) {
                CERROR("%s: can't locate next device: %s\n",
-                      m->mdt_md_dev.md_lu_dev.ld_obd->obd_name, next);
+                      mdt_obd_name(m), next);
                GOTO(out, rc = -ENOTCONN);
        }
 
@@ -4062,7 +3869,7 @@ static int mdt_connect_to_next(const struct lu_env *env, struct mdt_device *m,
        rc = obd_connect(NULL, exp, obd, &obd->obd_uuid, data, NULL);
        if (rc) {
                CERROR("%s: cannot connect to next dev %s (%d)\n",
-                      m->mdt_md_dev.md_lu_dev.ld_obd->obd_name, next, rc);
+                      mdt_obd_name(m), next, rc);
                GOTO(out, rc);
        }
 
@@ -4126,7 +3933,7 @@ static int mdt_stack_init(const struct lu_env *env, struct mdt_device *mdt,
        strcpy(name, dev);
        p = strstr(name, "-MDT");
        if (p == NULL)
-               GOTO(cleanup_mem, rc = -ENOMEM);
+               GOTO(free_bufs, rc = -ENOMEM);
        p[3] = 'D';
 
        snprintf(uuid, MAX_OBD_NAME, "%s_UUID", name);
@@ -4135,7 +3942,7 @@ static int mdt_stack_init(const struct lu_env *env, struct mdt_device *mdt,
        if (lprof == NULL || lprof->lp_dt == NULL) {
                CERROR("can't find the profile: %s\n",
                       lustre_cfg_string(cfg, 0));
-               GOTO(cleanup_mem, rc = -EINVAL);
+               GOTO(free_bufs, rc = -EINVAL);
        }
 
        lustre_cfg_bufs_reset(bufs, name);
@@ -4174,30 +3981,28 @@ static int mdt_stack_init(const struct lu_env *env, struct mdt_device *mdt,
        /* connect to MDD we just setup */
        rc = mdt_connect_to_next(env, mdt, name, &mdt->mdt_child_exp);
        if (rc)
-               RETURN(rc);
+               GOTO(class_detach, rc);
 
        site = mdt->mdt_child_exp->exp_obd->obd_lu_dev->ld_site;
        LASSERT(site);
-       LASSERT(mdt->mdt_md_dev.md_lu_dev.ld_site == NULL);
-       mdt->mdt_md_dev.md_lu_dev.ld_site = site;
-       site->ls_top_dev = &mdt->mdt_md_dev.md_lu_dev;
+       LASSERT(mdt_lu_site(mdt) == NULL);
+       mdt->mdt_lu_dev.ld_site = site;
+       site->ls_top_dev = &mdt->mdt_lu_dev;
        mdt->mdt_child = lu2md_dev(mdt->mdt_child_exp->exp_obd->obd_lu_dev);
 
-
        /* now connect to bottom OSD */
        snprintf(name, MAX_OBD_NAME, "%s-osd", dev);
        rc = mdt_connect_to_next(env, mdt, name, &mdt->mdt_bottom_exp);
        if (rc)
-               RETURN(rc);
+               GOTO(class_detach, rc);
        mdt->mdt_bottom =
                lu2dt_dev(mdt->mdt_bottom_exp->exp_obd->obd_lu_dev);
 
-
        rc = lu_env_refill((struct lu_env *)env);
        if (rc != 0)
                CERROR("Failure to refill session: '%d'\n", rc);
 
-       lu_dev_add_linkage(site, &mdt->mdt_md_dev.md_lu_dev);
+       lu_dev_add_linkage(site, &mdt->mdt_lu_dev);
 
        EXIT;
 class_detach:
@@ -4308,7 +4113,7 @@ static int mdt_quota_init(const struct lu_env *env, struct mdt_device *mdt,
 
        /* configure local quota objects */
        rc = mdt->mdt_qmt_dev->ld_ops->ldo_prepare(env,
-                                                  &mdt->mdt_md_dev.md_lu_dev,
+                                                  &mdt->mdt_lu_dev,
                                                   mdt->mdt_qmt_dev);
        if (rc)
                GOTO(class_cleanup, rc);
@@ -4363,19 +4168,147 @@ static void mdt_quota_fini(const struct lu_env *env, struct mdt_device *mdt)
        EXIT;
 }
 
-static void mdt_fini(const struct lu_env *env, struct mdt_device *m)
+/* mdt_getxattr() is used from mdt_intent_getxattr(), use this wrapper
+ * for now. This will be removed along with converting rest of MDT code
+ * to use tgt_session_info */
+int mdt_tgt_getxattr(struct tgt_session_info *tsi)
 {
-        struct md_device  *next = m->mdt_child;
-        struct lu_device  *d    = &m->mdt_md_dev.md_lu_dev;
-        struct obd_device *obd = mdt2obd_dev(m);
-        ENTRY;
+       struct mdt_thread_info  *info = tsi2mdt_info(tsi);
+       int                      rc;
+
+       rc = mdt_getxattr(info);
+
+       mdt_thread_info_fini(info);
+       return rc;
+}
+
+static struct tgt_handler mdt_tgt_handlers[] = {
+TGT_RPC_HANDLER(MDS_FIRST_OPC,
+               0,                      MDS_CONNECT,    mdt_tgt_connect,
+               &RQF_CONNECT, LUSTRE_OBD_VERSION),
+TGT_RPC_HANDLER(MDS_FIRST_OPC,
+               0,                      MDS_DISCONNECT, tgt_disconnect,
+               &RQF_MDS_DISCONNECT, LUSTRE_OBD_VERSION),
+TGT_RPC_HANDLER(MDS_FIRST_OPC,
+               HABEO_REFERO,           MDS_SET_INFO,   mdt_set_info,
+               &RQF_OBD_SET_INFO, LUSTRE_MDS_VERSION),
+TGT_MDT_HDL(0,                         MDS_GET_INFO,   mdt_get_info),
+TGT_MDT_HDL(0          | HABEO_REFERO, MDS_GETSTATUS,  mdt_getstatus),
+TGT_MDT_HDL(HABEO_CORPUS,              MDS_GETATTR,    mdt_getattr),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO,        MDS_GETATTR_NAME,
+                                                       mdt_getattr_name),
+TGT_MDT_HDL(HABEO_CORPUS,              MDS_GETXATTR,   mdt_tgt_getxattr),
+TGT_MDT_HDL(0          | HABEO_REFERO, MDS_STATFS,     mdt_statfs),
+TGT_MDT_HDL(0          | MUTABOR,      MDS_REINT,      mdt_reint),
+TGT_MDT_HDL(HABEO_CORPUS,              MDS_CLOSE,      mdt_close),
+TGT_MDT_HDL(HABEO_CORPUS,              MDS_DONE_WRITING,
+                                                       mdt_done_writing),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO,        MDS_READPAGE,   mdt_readpage),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO,        MDS_SYNC,       mdt_sync),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO,        MDS_IS_SUBDIR,  mdt_is_subdir),
+TGT_MDT_HDL(0,                         MDS_QUOTACTL,   mdt_quotactl),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO | MUTABOR, MDS_HSM_PROGRESS,
+                                                       mdt_hsm_progress),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO | MUTABOR, MDS_HSM_CT_REGISTER,
+                                                       mdt_hsm_ct_register),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO | MUTABOR, MDS_HSM_CT_UNREGISTER,
+                                                       mdt_hsm_ct_unregister),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO, MDS_HSM_STATE_GET,
+                                                       mdt_hsm_state_get),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO | MUTABOR, MDS_HSM_STATE_SET,
+                                                       mdt_hsm_state_set),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO, MDS_HSM_ACTION,        mdt_hsm_action),
+TGT_MDT_HDL(HABEO_CORPUS| HABEO_REFERO, MDS_HSM_REQUEST,
+                                                       mdt_hsm_request),
+TGT_MDT_HDL(HABEO_CORPUS|HABEO_REFERO | MUTABOR, MDS_SWAP_LAYOUTS,
+                                                       mdt_swap_layouts)
+};
+
+static struct tgt_handler mdt_sec_ctx_ops[] = {
+TGT_SEC_HDL_VAR(0,                     SEC_CTX_INIT,     mdt_sec_ctx_handle),
+TGT_SEC_HDL_VAR(0,                     SEC_CTX_INIT_CONT,mdt_sec_ctx_handle),
+TGT_SEC_HDL_VAR(0,                     SEC_CTX_FINI,     mdt_sec_ctx_handle)
+};
+
+static struct tgt_handler mdt_quota_ops[] = {
+TGT_QUOTA_HDL(HABEO_REFERO,            QUOTA_DQACQ,      mdt_quota_dqacq),
+};
 
-        target_recovery_fini(obd);
+static struct tgt_opc_slice mdt_common_slice[] = {
+       {
+               .tos_opc_start  = MDS_FIRST_OPC,
+               .tos_opc_end    = MDS_LAST_OPC,
+               .tos_hs         = mdt_tgt_handlers
+       },
+       {
+               .tos_opc_start  = OBD_FIRST_OPC,
+               .tos_opc_end    = OBD_LAST_OPC,
+               .tos_hs         = tgt_obd_handlers
+       },
+       {
+               .tos_opc_start  = LDLM_FIRST_OPC,
+               .tos_opc_end    = LDLM_LAST_OPC,
+               .tos_hs         = tgt_dlm_handlers
+       },
+       {
+               .tos_opc_start  = SEC_FIRST_OPC,
+               .tos_opc_end    = SEC_LAST_OPC,
+               .tos_hs         = mdt_sec_ctx_ops
+       },
+       {
+               .tos_opc_start  = OUT_UPDATE_FIRST_OPC,
+               .tos_opc_end    = OUT_UPDATE_LAST_OPC,
+               .tos_hs         = tgt_out_handlers
+       },
+       {
+               .tos_opc_start  = FLD_FIRST_OPC,
+               .tos_opc_end    = FLD_LAST_OPC,
+               .tos_hs         = fld_handlers
+       },
+       {
+               .tos_opc_start  = SEQ_FIRST_OPC,
+               .tos_opc_end    = SEQ_LAST_OPC,
+               .tos_hs         = seq_handlers
+       },
+       {
+               .tos_opc_start  = QUOTA_DQACQ,
+               .tos_opc_end    = QUOTA_LAST_OPC,
+               .tos_hs         = mdt_quota_ops
+       },
+       {
+               .tos_opc_start  = LLOG_FIRST_OPC,
+               .tos_opc_end    = LLOG_LAST_OPC,
+               .tos_hs         = tgt_llog_handlers
+       },
+       {
+               .tos_opc_start  = LFSCK_FIRST_OPC,
+               .tos_opc_end    = LFSCK_LAST_OPC,
+               .tos_hs         = tgt_lfsck_handlers
+       },
 
-        ping_evictor_stop();
+       {
+               .tos_hs         = NULL
+       }
+};
 
+static void mdt_fini(const struct lu_env *env, struct mdt_device *m)
+{
+       struct md_device        *next = m->mdt_child;
+       struct lu_device        *d    = &m->mdt_lu_dev;
+       struct obd_device       *obd  = mdt2obd_dev(m);
+       struct lfsck_stop        stop;
+       ENTRY;
 
+       target_recovery_fini(obd);
+       ping_evictor_stop();
        mdt_stack_pre_fini(env, m, md2lu_dev(m->mdt_child));
+
+       if (m->mdt_opts.mo_coordinator)
+               mdt_hsm_cdt_stop(m);
+
+       mdt_hsm_cdt_fini(m);
+
+       mdt_llog_ctxt_unclone(env, m, LLOG_AGENT_ORIG_CTXT);
         mdt_llog_ctxt_unclone(env, m, LLOG_CHANGELOG_ORIG_CTXT);
         obd_exports_barrier(obd);
         obd_zombie_barrier();
@@ -4402,48 +4335,27 @@ static void mdt_fini(const struct lu_env *env, struct mdt_device *m)
                 m->mdt_nosquash_strlen = 0;
         }
 
+       stop.ls_status = LS_PAUSED;
+       stop.ls_flags = 0;
+       next->md_ops->mdo_iocontrol(env, next, OBD_IOC_STOP_LFSCK, 0, &stop);
+
         mdt_seq_fini(env, m);
         mdt_fld_fini(env, m);
-        sptlrpc_rule_set_free(&m->mdt_sptlrpc_rset);
 
         next->md_ops->mdo_init_capa_ctxt(env, next, 0, 0, 0, NULL);
         cfs_timer_disarm(&m->mdt_ck_timer);
         mdt_ck_thread_stop(m);
 
-        /*
-         * Finish the stack
-         */
-        mdt_stack_fini(env, m, md2lu_dev(m->mdt_child));
-
-        LASSERT(cfs_atomic_read(&d->ld_ref) == 0);
-
-       server_put_mount(mdt2obd_dev(m)->obd_name, NULL);
-
-        EXIT;
-}
-
-static int mdt_adapt_sptlrpc_conf(struct obd_device *obd, int initial)
-{
-        struct mdt_device       *m = mdt_dev(obd->obd_lu_dev);
-        struct sptlrpc_rule_set  tmp_rset;
-        int                      rc;
-
-        sptlrpc_rule_set_init(&tmp_rset);
-        rc = sptlrpc_conf_target_get_rules(obd, &tmp_rset, initial);
-        if (rc) {
-                CERROR("mdt %s: failed get sptlrpc rules: %d\n",
-                       obd->obd_name, rc);
-                return rc;
-        }
+       /*
+        * Finish the stack
+        */
+       mdt_stack_fini(env, m, md2lu_dev(m->mdt_child));
 
-        sptlrpc_target_update_exp_flavor(obd, &tmp_rset);
+       LASSERT(atomic_read(&d->ld_ref) == 0);
 
-       write_lock(&m->mdt_sptlrpc_lock);
-        sptlrpc_rule_set_free(&m->mdt_sptlrpc_rset);
-        m->mdt_sptlrpc_rset = tmp_rset;
-       write_unlock(&m->mdt_sptlrpc_lock);
+       server_put_mount(mdt_obd_name(m));
 
-        return 0;
+       EXIT;
 }
 
 int mdt_postrecov(const struct lu_env *, struct mdt_device *);
@@ -4462,11 +4374,11 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
         const char                *identity_upcall = "NONE";
         struct md_device          *next;
         int                        rc;
-        int                        node_id;
+       long                       node_id;
         mntopt_t                   mntopts;
         ENTRY;
 
-        md_device_init(&m->mdt_md_dev, ldt);
+       lu_device_init(&m->mdt_lu_dev, ldt);
         /*
          * Environment (env) might be missing mdt_thread_key values at that
          * point, if device is allocated when mdt_thread_key is in QUIESCENT
@@ -4490,6 +4402,11 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
         m->mdt_som_conf = 0;
 
         m->mdt_opts.mo_cos = MDT_COS_DEFAULT;
+
+       /* default is coordinator off, it is started through conf_param
+        * or /proc */
+       m->mdt_opts.mo_coordinator = 0;
+
        lmi = server_get_mount(dev);
         if (lmi == NULL) {
                 CERROR("Cannot get mount info for %s!\n", dev);
@@ -4500,15 +4417,9 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
                 LASSERT(num);
                 node_id = simple_strtol(num, NULL, 10);
                obd->u.obt.obt_magic = OBT_MAGIC;
-        }
-
-       rwlock_init(&m->mdt_sptlrpc_lock);
-        sptlrpc_rule_set_init(&m->mdt_sptlrpc_rset);
+       }
 
        spin_lock_init(&m->mdt_ioepoch_lock);
-        m->mdt_opts.mo_compat_resname = 0;
-        m->mdt_opts.mo_mds_capa = 1;
-        m->mdt_opts.mo_oss_capa = 1;
         m->mdt_capa_timeout = CAPA_TIMEOUT;
         m->mdt_capa_alg = CAPA_HMAC_ALG_SHA1;
         m->mdt_ck_timeout = CAPA_KEY_TIMEOUT;
@@ -4521,21 +4432,23 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
        spin_lock_init(&m->mdt_osfs_lock);
        m->mdt_osfs_age = cfs_time_shift_64(-1000);
        m->mdt_enable_remote_dir = 0;
+       m->mdt_enable_remote_dir_gid = 0;
 
-        m->mdt_md_dev.md_lu_dev.ld_ops = &mdt_lu_ops;
-        m->mdt_md_dev.md_lu_dev.ld_obd = obd;
-        /* set this lu_device to obd, because error handling need it */
-        obd->obd_lu_dev = &m->mdt_md_dev.md_lu_dev;
+       m->mdt_lu_dev.ld_ops = &mdt_lu_ops;
+       m->mdt_lu_dev.ld_obd = obd;
+       /* Set this lu_device to obd for error handling purposes. */
+       obd->obd_lu_dev = &m->mdt_lu_dev;
 
        /* init the stack */
        rc = mdt_stack_init((struct lu_env *)env, m, cfg);
        if (rc) {
-               CERROR("Can't init device stack, rc %d\n", rc);
+               CERROR("%s: Can't init device stack, rc %d\n",
+                      mdt_obd_name(m), rc);
                GOTO(err_lmi, rc);
        }
 
-       s = m->mdt_md_dev.md_lu_dev.ld_site;
-       ss_site = &m->mdt_seq_site;
+       s = mdt_lu_site(m);
+       ss_site = mdt_seq_site(m);
        s->ld_seq_site = ss_site;
        ss_site->ss_lu = s;
 
@@ -4550,28 +4463,24 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
         /* No connection accepted until configurations will finish */
         obd->obd_no_conn = 1;
 
-        if (cfg->lcfg_bufcount > 4 && LUSTRE_CFG_BUFLEN(cfg, 4) > 0) {
-                char *str = lustre_cfg_string(cfg, 4);
-                if (strchr(str, 'n')) {
-                        CWARN("%s: recovery disabled\n", obd->obd_name);
-                        obd->obd_replayable = 0;
-                }
-        }
-
-        rc = tgt_init(env, &m->mdt_lut, obd, m->mdt_bottom);
-        if (rc)
-                GOTO(err_fini_stack, rc);
+       if (cfg->lcfg_bufcount > 4 && LUSTRE_CFG_BUFLEN(cfg, 4) > 0) {
+               char *str = lustre_cfg_string(cfg, 4);
+               if (strchr(str, 'n')) {
+                       CWARN("%s: recovery disabled\n", mdt_obd_name(m));
+                       obd->obd_replayable = 0;
+               }
+       }
 
-       rc = mdt_fld_init(env, obd->obd_name, m);
+       rc = mdt_fld_init(env, mdt_obd_name(m), m);
        if (rc)
-               GOTO(err_lut, rc);
+               GOTO(err_fini_stack, rc);
 
-       rc = mdt_seq_init(env, obd->obd_name, m);
+       rc = mdt_seq_init(env, m);
        if (rc)
                GOTO(err_fini_fld, rc);
 
-        snprintf(info->mti_u.ns_name, sizeof info->mti_u.ns_name,
-                 LUSTRE_MDT_NAME"-%p", m);
+       snprintf(info->mti_u.ns_name, sizeof(info->mti_u.ns_name), "%s-%s",
+                LUSTRE_MDT_NAME, obd->obd_uuid.uuid);
         m->mdt_namespace = ldlm_namespace_new(obd, info->mti_u.ns_name,
                                               LDLM_NAMESPACE_SERVER,
                                               LDLM_NAMESPACE_GREEDY,
@@ -4588,44 +4497,62 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
 
         cfs_timer_init(&m->mdt_ck_timer, mdt_ck_timer_callback, m);
 
-        rc = mdt_ck_thread_start(m);
-        if (rc)
+       rc = mdt_hsm_cdt_init(m);
+       if (rc != 0) {
+               CERROR("%s: error initializing coordinator, rc %d\n",
+                      mdt_obd_name(m), rc);
                 GOTO(err_free_ns, rc);
+       }
 
-        rc = mdt_fs_setup(env, m, obd, lsi);
+        rc = mdt_ck_thread_start(m);
         if (rc)
-                GOTO(err_capa, rc);
+                GOTO(err_free_hsm, rc);
+
+       rc = tgt_init(env, &m->mdt_lut, obd, m->mdt_bottom, mdt_common_slice,
+                     OBD_FAIL_MDS_ALL_REQUEST_NET,
+                     OBD_FAIL_MDS_ALL_REPLY_NET);
+       if (rc)
+               GOTO(err_capa, rc);
 
-        mdt_adapt_sptlrpc_conf(obd, 1);
+       rc = mdt_fs_setup(env, m, obd, lsi);
+       if (rc)
+               GOTO(err_tgt, rc);
+
+       tgt_adapt_sptlrpc_conf(&m->mdt_lut, 1);
 
         next = m->mdt_child;
         rc = next->md_ops->mdo_iocontrol(env, next, OBD_IOC_GET_MNTOPT, 0,
                                          &mntopts);
         if (rc)
-               GOTO(err_llog_cleanup, rc);
+               GOTO(err_fs_cleanup, rc);
 
         if (mntopts & MNTOPT_USERXATTR)
                 m->mdt_opts.mo_user_xattr = 1;
         else
                 m->mdt_opts.mo_user_xattr = 0;
 
+       rc = next->md_ops->mdo_maxeasize_get(env, next, &m->mdt_max_ea_size);
+       if (rc)
+               GOTO(err_fs_cleanup, rc);
+
         if (mntopts & MNTOPT_ACL)
                 m->mdt_opts.mo_acl = 1;
         else
                 m->mdt_opts.mo_acl = 0;
 
-        /* XXX: to support suppgid for ACL, we enable identity_upcall
-         * by default, otherwise, maybe got unexpected -EACCESS. */
-        if (m->mdt_opts.mo_acl)
-                identity_upcall = MDT_IDENTITY_UPCALL_PATH;
-
-        m->mdt_identity_cache = upcall_cache_init(obd->obd_name,identity_upcall,
-                                                &mdt_identity_upcall_cache_ops);
-        if (IS_ERR(m->mdt_identity_cache)) {
-                rc = PTR_ERR(m->mdt_identity_cache);
-                m->mdt_identity_cache = NULL;
-               GOTO(err_llog_cleanup, rc);
-        }
+       /* XXX: to support suppgid for ACL, we enable identity_upcall
+        * by default, otherwise, maybe got unexpected -EACCESS. */
+       if (m->mdt_opts.mo_acl)
+               identity_upcall = MDT_IDENTITY_UPCALL_PATH;
+
+       m->mdt_identity_cache = upcall_cache_init(mdt_obd_name(m),
+                                               identity_upcall,
+                                               &mdt_identity_upcall_cache_ops);
+       if (IS_ERR(m->mdt_identity_cache)) {
+               rc = PTR_ERR(m->mdt_identity_cache);
+               m->mdt_identity_cache = NULL;
+               GOTO(err_fs_cleanup, rc);
+       }
 
         rc = mdt_procfs_init(m, dev);
         if (rc) {
@@ -4641,7 +4568,7 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
        ptlrpc_init_client(LDLM_CB_REQUEST_PORTAL, LDLM_CB_REPLY_PORTAL,
                           "mdt_ldlm_client", m->mdt_ldlm_client);
 
-        ping_evictor_start();
+       ping_evictor_start();
 
        /* recovery will be started upon mdt_prepare()
         * when the whole stack is complete and ready
@@ -4656,34 +4583,34 @@ static int mdt_init0(const struct lu_env *env, struct mdt_device *m,
                 ldlm_timeout = MDS_LDLM_TIMEOUT_DEFAULT;
 
         RETURN(0);
-
 err_procfs:
-        mdt_procfs_fini(m);
+       mdt_procfs_fini(m);
 err_recovery:
-        target_recovery_fini(obd);
-        upcall_cache_cleanup(m->mdt_identity_cache);
-        m->mdt_identity_cache = NULL;
-err_llog_cleanup:
-        mdt_llog_ctxt_unclone(env, m, LLOG_CHANGELOG_ORIG_CTXT);
-        mdt_fs_cleanup(env, m);
+       target_recovery_fini(obd);
+       upcall_cache_cleanup(m->mdt_identity_cache);
+       m->mdt_identity_cache = NULL;
+err_fs_cleanup:
+       mdt_fs_cleanup(env, m);
+err_tgt:
+       tgt_fini(env, &m->mdt_lut);
 err_capa:
-        cfs_timer_disarm(&m->mdt_ck_timer);
-        mdt_ck_thread_stop(m);
+       cfs_timer_disarm(&m->mdt_ck_timer);
+       mdt_ck_thread_stop(m);
+err_free_hsm:
+       mdt_hsm_cdt_fini(m);
 err_free_ns:
-        ldlm_namespace_free(m->mdt_namespace, NULL, 0);
-        obd->obd_namespace = m->mdt_namespace = NULL;
+       ldlm_namespace_free(m->mdt_namespace, NULL, 0);
+       obd->obd_namespace = m->mdt_namespace = NULL;
 err_fini_seq:
        mdt_seq_fini(env, m);
 err_fini_fld:
        mdt_fld_fini(env, m);
-err_lut:
-       tgt_fini(env, &m->mdt_lut);
 err_fini_stack:
-        mdt_stack_fini(env, m, md2lu_dev(m->mdt_child));
+       mdt_stack_fini(env, m, md2lu_dev(m->mdt_child));
 err_lmi:
        if (lmi)
-               server_put_mount(dev, lmi->lmi_mnt);
-        return (rc);
+               server_put_mount(dev);
+       return(rc);
 }
 
 /* For interoperability, the left element is old parameter, the right one
@@ -4748,9 +4675,16 @@ static int mdt_process_config(const struct lu_env *env,
                lprocfs_mdt_init_vars(&lvars);
                rc = class_process_proc_param(PARAM_MDT, lvars.obd_vars,
                                              cfg, obd);
-               if (rc > 0 || rc == -ENOSYS)
-                       /* we don't understand; pass it on */
-                       rc = next->ld_ops->ldo_process_config(env, next, cfg);
+               if (rc > 0 || rc == -ENOSYS) {
+                       /* is it an HSM var ? */
+                       rc = class_process_proc_param(PARAM_HSM,
+                                                     hsm_cdt_get_proc_vars(),
+                                                     cfg, obd);
+                       if (rc > 0 || rc == -ENOSYS)
+                               /* we don't understand; pass it on */
+                               rc = next->ld_ops->ldo_process_config(env, next,
+                                                                     cfg);
+               }
 
                if (old_cfg != NULL)
                        lustre_cfg_free(cfg);
@@ -4766,29 +4700,30 @@ static int mdt_process_config(const struct lu_env *env,
 }
 
 static struct lu_object *mdt_object_alloc(const struct lu_env *env,
-                                          const struct lu_object_header *hdr,
-                                          struct lu_device *d)
+                                         const struct lu_object_header *hdr,
+                                         struct lu_device *d)
 {
-        struct mdt_object *mo;
+       struct mdt_object *mo;
 
-        ENTRY;
+       ENTRY;
 
-       OBD_SLAB_ALLOC_PTR_GFP(mo, mdt_object_kmem, CFS_ALLOC_IO);
-        if (mo != NULL) {
-                struct lu_object *o;
-                struct lu_object_header *h;
-
-                o = &mo->mot_obj.mo_lu;
-                h = &mo->mot_header;
-                lu_object_header_init(h);
-                lu_object_init(o, h, d);
-                lu_object_add_top(h, o);
-                o->lo_ops = &mdt_obj_ops;
+       OBD_SLAB_ALLOC_PTR_GFP(mo, mdt_object_kmem, GFP_NOFS);
+       if (mo != NULL) {
+               struct lu_object *o;
+               struct lu_object_header *h;
+
+               o = &mo->mot_obj;
+               h = &mo->mot_header;
+               lu_object_header_init(h);
+               lu_object_init(o, h, d);
+               lu_object_add_top(h, o);
+               o->lo_ops = &mdt_obj_ops;
                mutex_init(&mo->mot_ioepoch_mutex);
                mutex_init(&mo->mot_lov_mutex);
-                RETURN(o);
-        } else
-                RETURN(NULL);
+               init_rwsem(&mo->mot_open_sem);
+               RETURN(o);
+       }
+       RETURN(NULL);
 }
 
 static int mdt_object_init(const struct lu_env *env, struct lu_object *o,
@@ -4823,11 +4758,14 @@ static void mdt_object_free(const struct lu_env *env, struct lu_object *o)
         CDEBUG(D_INFO, "object free, fid = "DFID"\n",
                PFID(lu_object_fid(o)));
 
-        lu_object_fini(o);
-        lu_object_header_fini(h);
+       LASSERT(atomic_read(&mo->mot_open_count) == 0);
+       LASSERT(atomic_read(&mo->mot_lease_count) == 0);
+
+       lu_object_fini(o);
+       lu_object_header_fini(h);
        OBD_SLAB_FREE_PTR(mo, mdt_object_kmem);
 
-        EXIT;
+       EXIT;
 }
 
 static int mdt_object_print(const struct lu_env *env, void *cookie,
@@ -4847,6 +4785,7 @@ static int mdt_prepare(const struct lu_env *env,
        struct mdt_device *mdt = mdt_dev(cdev);
        struct lu_device *next = &mdt->mdt_child->md_lu_dev;
        struct obd_device *obd = cdev->ld_obd;
+       struct lfsck_start_param lsp;
        int rc;
 
        ENTRY;
@@ -4861,13 +4800,35 @@ static int mdt_prepare(const struct lu_env *env,
        if (rc)
                RETURN(rc);
 
-       rc = mdt->mdt_child->md_ops->mdo_root_get(env, mdt->mdt_child,
-                                                 &mdt->mdt_md_root_fid);
+       rc = mdt_llog_ctxt_clone(env, mdt, LLOG_AGENT_ORIG_CTXT);
        if (rc)
                RETURN(rc);
 
+       rc = lfsck_register_namespace(env, mdt->mdt_bottom, mdt->mdt_namespace);
+       /* The LFSCK instance is registered just now, so it must be there when
+        * register the namespace to such instance. */
+       LASSERTF(rc == 0, "register namespace failed: rc = %d\n", rc);
+
+       lsp.lsp_start = NULL;
+       lsp.lsp_index_valid = 0;
+       rc = mdt->mdt_child->md_ops->mdo_iocontrol(env, mdt->mdt_child,
+                                                  OBD_IOC_START_LFSCK,
+                                                  0, &lsp);
+       if (rc != 0) {
+               CWARN("%s: auto trigger paused LFSCK failed: rc = %d\n",
+                     mdt_obd_name(mdt), rc);
+               rc = 0;
+       }
+
+       if (mdt->mdt_seq_site.ss_node_id == 0) {
+               rc = mdt->mdt_child->md_ops->mdo_root_get(env, mdt->mdt_child,
+                                                        &mdt->mdt_md_root_fid);
+               if (rc)
+                       RETURN(rc);
+       }
+
        LASSERT(!test_bit(MDT_FL_CFGLOG, &mdt->mdt_state));
-       target_recovery_init(&mdt->mdt_lut, mdt_recovery_handle);
+       target_recovery_init(&mdt->mdt_lut, tgt_request_handle);
        set_bit(MDT_FL_CFGLOG, &mdt->mdt_state);
        LASSERT(obd->obd_no_conn);
        spin_lock(&obd->obd_dev_lock);
@@ -4898,18 +4859,16 @@ static int mdt_obd_set_info_async(const struct lu_env *env,
                                   __u32 vallen, void *val,
                                   struct ptlrpc_request_set *set)
 {
-        struct obd_device     *obd = exp->exp_obd;
-        int                    rc;
-        ENTRY;
+       int rc;
 
-        LASSERT(obd);
+       ENTRY;
 
-        if (KEY_IS(KEY_SPTLRPC_CONF)) {
-                rc = mdt_adapt_sptlrpc_conf(obd, 0);
-                RETURN(rc);
-        }
+       if (KEY_IS(KEY_SPTLRPC_CONF)) {
+               rc = tgt_adapt_sptlrpc_conf(class_exp2tgt(exp), 0);
+               RETURN(rc);
+       }
 
-        RETURN(0);
+       RETURN(0);
 }
 
 /**
@@ -4918,12 +4877,12 @@ static int mdt_obd_set_info_async(const struct lu_env *env,
  * Compute the compatibility flags for a connection request based on
  * features mutually supported by client and server.
  *
- * The obd_export::exp_connect_flags field in \a exp must not be updated
- * here, otherwise a partially initialized value may be exposed. After
- * the connection request is successfully processed, the top-level MDT
- * connect request handler atomically updates the export connect flags
- * from the obd_connect_data::ocd_connect_flags field of the reply.
- * \see mdt_connect().
+ * The obd_export::exp_connect_data.ocd_connect_flags field in \a exp
+ * must not be updated here, otherwise a partially initialized value may
+ * be exposed. After the connection request is successfully processed,
+ * the top-level MDT connect request handler atomically updates the export
+ * connect flags from the obd_connect_data::ocd_connect_flags field of the
+ * reply. \see mdt_connect().
  *
  * \param exp   the obd_export associated with this client/target pair
  * \param mdt   the target device for the connection
@@ -4960,7 +4919,7 @@ static int mdt_connect_internal(struct obd_export *exp,
 
        if (data->ocd_connect_flags & OBD_CONNECT_BRW_SIZE) {
                data->ocd_brw_size = min(data->ocd_brw_size,
-                       (__u32)(PTLRPC_MAX_BRW_PAGES << CFS_PAGE_SHIFT));
+                                        (__u32)MD_MAX_BRW_SIZE);
                if (data->ocd_brw_size == 0) {
                        CERROR("%s: cli %s/%p ocd_connect_flags: "LPX64
                               " ocd_version: %x ocd_grant: %d "
@@ -4968,7 +4927,7 @@ static int mdt_connect_internal(struct obd_export *exp,
                               "unexpectedly zero, network data "
                               "corruption? Refusing connection of this"
                               " client\n",
-                              exp->exp_obd->obd_name,
+                              mdt_obd_name(mdt),
                               exp->exp_client_uuid.uuid,
                               exp, data->ocd_connect_flags, data->ocd_version,
                               data->ocd_grant, data->ocd_index);
@@ -4976,22 +4935,22 @@ static int mdt_connect_internal(struct obd_export *exp,
                }
        }
 
-       /* NB: Disregard the rule against updating exp_connect_flags in this
-        * case, since tgt_client_new() needs to know if this is a lightweight
-        * connection, and it is safe to expose this flag before connection
-        * processing completes. */
+       /* NB: Disregard the rule against updating
+        * exp_connect_data.ocd_connect_flags in this case, since
+        * tgt_client_new() needs to know if this is a lightweight
+        * connection, and it is safe to expose this flag before
+        * connection processing completes. */
        if (data->ocd_connect_flags & OBD_CONNECT_LIGHTWEIGHT) {
                spin_lock(&exp->exp_lock);
-               exp->exp_connect_flags |=  OBD_CONNECT_LIGHTWEIGHT;
+               *exp_connect_flags_ptr(exp) |= OBD_CONNECT_LIGHTWEIGHT;
                spin_unlock(&exp->exp_lock);
        }
 
        data->ocd_version = LUSTRE_VERSION_CODE;
-       exp->exp_mdt_data.med_ibits_known = data->ocd_ibits_known;
 
        if ((data->ocd_connect_flags & OBD_CONNECT_FID) == 0) {
                CWARN("%s: MDS requires FID support, but client not\n",
-                     mdt->mdt_md_dev.md_lu_dev.ld_obd->obd_name);
+                     mdt_obd_name(mdt));
                return -EBADE;
        }
 
@@ -5000,55 +4959,23 @@ static int mdt_connect_internal(struct obd_export *exp,
                                         OBD_CONNECT_MDS_MDS |
                                         OBD_CONNECT_SOM))) {
                CWARN("%s: MDS has SOM enabled, but client does not support "
-                     "it\n", mdt->mdt_md_dev.md_lu_dev.ld_obd->obd_name);
+                     "it\n", mdt_obd_name(mdt));
                return -EBADE;
        }
 
-       return 0;
-}
-
-static int mdt_connect_check_sptlrpc(struct mdt_device *mdt,
-                                    struct obd_export *exp,
-                                    struct ptlrpc_request *req)
-{
-       struct sptlrpc_flavor   flvr;
-       int                     rc = 0;
-
-       if (exp->exp_flvr.sf_rpc == SPTLRPC_FLVR_INVALID) {
-               read_lock(&mdt->mdt_sptlrpc_lock);
-               sptlrpc_target_choose_flavor(&mdt->mdt_sptlrpc_rset,
-                                            req->rq_sp_from,
-                                            req->rq_peer.nid,
-                                            &flvr);
-               read_unlock(&mdt->mdt_sptlrpc_lock);
-
-               spin_lock(&exp->exp_lock);
-
-                exp->exp_sp_peer = req->rq_sp_from;
-                exp->exp_flvr = flvr;
-
-                if (exp->exp_flvr.sf_rpc != SPTLRPC_FLVR_ANY &&
-                    exp->exp_flvr.sf_rpc != req->rq_flvr.sf_rpc) {
-                        CERROR("unauthorized rpc flavor %x from %s, "
-                               "expect %x\n", req->rq_flvr.sf_rpc,
-                               libcfs_nid2str(req->rq_peer.nid),
-                               exp->exp_flvr.sf_rpc);
-                        rc = -EACCES;
-                }
+       if (OCD_HAS_FLAG(data, PINGLESS)) {
+               if (ptlrpc_pinger_suppress_pings()) {
+                       spin_lock(&exp->exp_obd->obd_dev_lock);
+                       list_del_init(&exp->exp_obd_chain_timed);
+                       spin_unlock(&exp->exp_obd->obd_dev_lock);
+               } else {
+                       data->ocd_connect_flags &= ~OBD_CONNECT_PINGLESS;
+               }
+       }
 
-               spin_unlock(&exp->exp_lock);
-        } else {
-                if (exp->exp_sp_peer != req->rq_sp_from) {
-                        CERROR("RPC source %s doesn't match %s\n",
-                               sptlrpc_part2name(req->rq_sp_from),
-                               sptlrpc_part2name(exp->exp_sp_peer));
-                        rc = -EACCES;
-                } else {
-                        rc = sptlrpc_target_export_check(exp, req);
-                }
-        }
+       data->ocd_max_easize = mdt->mdt_max_ea_size;
 
-        return rc;
+       return 0;
 }
 
 /* mds_connect copy */
@@ -5058,11 +4985,9 @@ static int mdt_obd_connect(const struct lu_env *env,
                            struct obd_connect_data *data,
                            void *localdata)
 {
-        struct mdt_thread_info *info;
         struct obd_export      *lexp;
         struct lustre_handle    conn = { 0 };
         struct mdt_device      *mdt;
-        struct ptlrpc_request  *req;
         int                     rc;
         ENTRY;
 
@@ -5070,18 +4995,18 @@ static int mdt_obd_connect(const struct lu_env *env,
         if (!exp || !obd || !cluuid)
                 RETURN(-EINVAL);
 
-        info = lu_context_key_get(&env->le_ctx, &mdt_thread_key);
-        req = info->mti_pill->rc_req;
-        mdt = mdt_dev(obd->obd_lu_dev);
+       mdt = mdt_dev(obd->obd_lu_dev);
 
        /*
         * first, check whether the stack is ready to handle requests
         * XXX: probably not very appropriate method is used now
         *      at some point we should find a better one
         */
-       if (!test_bit(MDT_FL_SYNCED, &mdt->mdt_state) &&
+       if (!test_bit(MDT_FL_SYNCED, &mdt->mdt_state) && data != NULL &&
            !(data->ocd_connect_flags & OBD_CONNECT_LIGHTWEIGHT)) {
-               rc = obd_health_check(env, mdt->mdt_child_exp->exp_obd);
+               rc = obd_get_info(env, mdt->mdt_child_exp,
+                                 sizeof(KEY_OSP_CONNECTED),
+                                 KEY_OSP_CONNECTED, NULL, NULL, NULL);
                if (rc)
                        RETURN(-EAGAIN);
                set_bit(MDT_FL_SYNCED, &mdt->mdt_state);
@@ -5094,26 +5019,20 @@ static int mdt_obd_connect(const struct lu_env *env,
         lexp = class_conn2export(&conn);
         LASSERT(lexp != NULL);
 
-        rc = mdt_connect_check_sptlrpc(mdt, lexp, req);
-        if (rc)
-                GOTO(out, rc);
-
-        if (OBD_FAIL_CHECK(OBD_FAIL_TGT_RCVG_FLAG))
-                lustre_msg_add_op_flags(req->rq_repmsg, MSG_CONNECT_RECOVERING);
-
         rc = mdt_connect_internal(lexp, mdt, data);
         if (rc == 0) {
                 struct lsd_client_data *lcd = lexp->exp_target_data.ted_lcd;
 
                 LASSERT(lcd);
-               info->mti_exp = lexp;
                memcpy(lcd->lcd_uuid, cluuid, sizeof lcd->lcd_uuid);
                rc = tgt_client_new(env, lexp);
                 if (rc == 0)
                         mdt_export_stats_init(obd, lexp, localdata);
+
+               /* For phase I, sync for cross-ref operation. */
+               lexp->exp_keep_sync = 1;
         }
 
-out:
         if (rc != 0) {
                 class_disconnect(lexp);
                 *exp = NULL;
@@ -5130,23 +5049,12 @@ static int mdt_obd_reconnect(const struct lu_env *env,
                              struct obd_connect_data *data,
                              void *localdata)
 {
-        struct mdt_thread_info *info;
-        struct mdt_device      *mdt;
-        struct ptlrpc_request  *req;
         int                     rc;
         ENTRY;
 
         if (exp == NULL || obd == NULL || cluuid == NULL)
                 RETURN(-EINVAL);
 
-        info = lu_context_key_get(&env->le_ctx, &mdt_thread_key);
-        req = info->mti_pill->rc_req;
-        mdt = mdt_dev(obd->obd_lu_dev);
-
-        rc = mdt_connect_check_sptlrpc(mdt, exp, req);
-        if (rc)
-                RETURN(rc);
-
         rc = mdt_connect_internal(exp, mdt_dev(obd->obd_lu_dev), data);
         if (rc == 0)
                 mdt_export_stats_init(obd, exp, localdata);
@@ -5154,6 +5062,31 @@ static int mdt_obd_reconnect(const struct lu_env *env,
         RETURN(rc);
 }
 
+static int mdt_ctxt_add_dirty_flag(struct lu_env *env,
+                                  struct mdt_thread_info *info,
+                                  struct mdt_file_data *mfd)
+{
+       struct lu_context ses;
+       int rc;
+       ENTRY;
+
+       rc = lu_context_init(&ses, LCT_SERVER_SESSION);
+       if (rc)
+               RETURN(rc);
+
+       env->le_ses = &ses;
+       lu_context_enter(&ses);
+
+       mdt_ucred(info)->uc_valid = UCRED_OLD;
+       rc = mdt_add_dirty_flag(info, mfd->mfd_object, &info->mti_attr);
+
+       lu_context_exit(&ses);
+       lu_context_fini(&ses);
+       env->le_ses = NULL;
+
+       RETURN(rc);
+}
+
 static int mdt_export_cleanup(struct obd_export *exp)
 {
         struct mdt_export_data *med = &exp->exp_mdt_data;
@@ -5198,6 +5131,24 @@ static int mdt_export_cleanup(struct obd_export *exp)
                 cfs_list_for_each_entry_safe(mfd, n, &closing_list, mfd_list) {
                         cfs_list_del_init(&mfd->mfd_list);
                        ma->ma_need = ma->ma_valid = 0;
+
+                       /* This file is being closed due to an eviction, it
+                        * could have been modified and now dirty regarding to
+                        * HSM archive, check this!
+                        * The logic here is to mark a file dirty if there's a
+                        * chance it was dirtied before the client was evicted,
+                        * so that we don't have to wait for a release attempt
+                        * before finding out the file was actually dirty and
+                        * fail the release. Aggressively marking it dirty here
+                        * will cause the policy engine to attempt to
+                        * re-archive it; when rearchiving, we can compare the
+                        * current version to the HSM data_version and make the
+                        * archive request into a noop if it's not actually
+                        * dirty.
+                        */
+                       if (mfd->mfd_mode & (FMODE_WRITE|MDS_FMODE_TRUNC))
+                               rc = mdt_ctxt_add_dirty_flag(&env, info, mfd);
+
                        /* Don't unlink orphan on failover umount, LU-184 */
                        if (exp->exp_flags & OBD_OPT_FAILOVER) {
                                ma->ma_valid = MA_FLAGS;
@@ -5294,32 +5245,199 @@ static int mdt_destroy_export(struct obd_export *exp)
         RETURN(0);
 }
 
-static int mdt_rpc_fid2path(struct mdt_thread_info *info, void *key,
-                            void *val, int vallen)
+/** The maximum depth that fid2path() will search.
+ * This is limited only because we want to store the fids for
+ * historical path lookup purposes.
+ */
+#define MAX_PATH_DEPTH 100
+
+/** mdt_path() lookup structure. */
+struct path_lookup_info {
+       __u64                   pli_recno;      /**< history point */
+       __u64                   pli_currec;     /**< current record */
+       struct lu_fid           pli_fid;
+       struct lu_fid           pli_fids[MAX_PATH_DEPTH]; /**< path, in fids */
+       struct mdt_object       *pli_mdt_obj;
+       char                    *pli_path;      /**< full path */
+       int                     pli_pathlen;
+       int                     pli_linkno;     /**< which hardlink to follow */
+       int                     pli_fidcount;   /**< number of \a pli_fids */
+};
+
+int mdt_links_read(struct mdt_thread_info *info, struct mdt_object *mdt_obj,
+                  struct linkea_data *ldata)
 {
-        struct mdt_device *mdt = mdt_dev(info->mti_exp->exp_obd->obd_lu_dev);
-        struct getinfo_fid2path *fpout, *fpin;
-        int rc = 0;
+       int rc;
 
-        fpin = key + cfs_size_round(sizeof(KEY_FID2PATH));
-        fpout = val;
+       LASSERT(ldata->ld_buf->lb_buf != NULL);
+
+       if (!mdt_object_exists(mdt_obj))
+               return -ENODATA;
+
+       rc = mo_xattr_get(info->mti_env, mdt_object_child(mdt_obj),
+                         ldata->ld_buf, XATTR_NAME_LINK);
+       if (rc == -ERANGE) {
+               /* Buf was too small, figure out what we need. */
+               lu_buf_free(ldata->ld_buf);
+               rc = mo_xattr_get(info->mti_env, mdt_object_child(mdt_obj),
+                                 ldata->ld_buf, XATTR_NAME_LINK);
+               if (rc < 0)
+                       return rc;
+               ldata->ld_buf = lu_buf_check_and_alloc(ldata->ld_buf, rc);
+               if (ldata->ld_buf->lb_buf == NULL)
+                       return -ENOMEM;
+               rc = mo_xattr_get(info->mti_env, mdt_object_child(mdt_obj),
+                                 ldata->ld_buf, XATTR_NAME_LINK);
+       }
+       if (rc < 0)
+               return rc;
 
-        if (ptlrpc_req_need_swab(info->mti_pill->rc_req))
-                lustre_swab_fid2path(fpin);
+       return linkea_init(ldata);
+}
 
-        memcpy(fpout, fpin, sizeof(*fpin));
-        if (fpout->gf_pathlen != vallen - sizeof(*fpin))
-                RETURN(-EINVAL);
+static int mdt_path_current(struct mdt_thread_info *info,
+                           struct path_lookup_info *pli)
+{
+       struct mdt_device       *mdt = info->mti_mdt;
+       struct mdt_object       *mdt_obj;
+       struct link_ea_header   *leh;
+       struct link_ea_entry    *lee;
+       struct lu_name          *tmpname = &info->mti_name;
+       struct lu_fid           *tmpfid = &info->mti_tmp_fid1;
+       struct lu_buf           *buf = &info->mti_big_buf;
+       char                    *ptr;
+       int                     reclen;
+       struct linkea_data      ldata = { 0 };
+       int                     rc = 0;
+       ENTRY;
 
-        rc = mdt_fid2path(info->mti_env, mdt, fpout);
-        RETURN(rc);
+       /* temp buffer for path element, the buffer will be finally freed
+        * in mdt_thread_info_fini */
+       buf = lu_buf_check_and_alloc(buf, PATH_MAX);
+       if (buf->lb_buf == NULL)
+               RETURN(-ENOMEM);
+
+       ldata.ld_buf = buf;
+       ptr = pli->pli_path + pli->pli_pathlen - 1;
+       *ptr = 0;
+       --ptr;
+       pli->pli_fidcount = 0;
+       pli->pli_fids[0] = *(struct lu_fid *)mdt_object_fid(pli->pli_mdt_obj);
+
+       /* root FID only exists on MDT0, and fid2path should also ends at MDT0,
+        * so checking root_fid can only happen on MDT0. */
+       while (!lu_fid_eq(&mdt->mdt_md_root_fid,
+                         &pli->pli_fids[pli->pli_fidcount])) {
+               mdt_obj = mdt_object_find(info->mti_env, mdt,
+                                         &pli->pli_fids[pli->pli_fidcount]);
+               if (IS_ERR(mdt_obj))
+                       GOTO(out, rc = PTR_ERR(mdt_obj));
+               if (mdt_object_remote(mdt_obj)) {
+                       mdt_object_put(info->mti_env, mdt_obj);
+                       GOTO(remote_out, rc = -EREMOTE);
+               }
+               if (!mdt_object_exists(mdt_obj)) {
+                       mdt_object_put(info->mti_env, mdt_obj);
+                       GOTO(out, rc = -ENOENT);
+               }
+
+               rc = mdt_links_read(info, mdt_obj, &ldata);
+               mdt_object_put(info->mti_env, mdt_obj);
+               if (rc != 0)
+                       GOTO(out, rc);
+
+               leh = buf->lb_buf;
+               lee = (struct link_ea_entry *)(leh + 1); /* link #0 */
+               linkea_entry_unpack(lee, &reclen, tmpname, tmpfid);
+               /* If set, use link #linkno for path lookup, otherwise use
+                  link #0.  Only do this for the final path element. */
+               if (pli->pli_fidcount == 0 &&
+                   pli->pli_linkno < leh->leh_reccount) {
+                       int count;
+                       for (count = 0; count < pli->pli_linkno; count++) {
+                               lee = (struct link_ea_entry *)
+                                    ((char *)lee + reclen);
+                               linkea_entry_unpack(lee, &reclen, tmpname,
+                                                   tmpfid);
+                       }
+                       if (pli->pli_linkno < leh->leh_reccount - 1)
+                               /* indicate to user there are more links */
+                               pli->pli_linkno++;
+               }
+
+               /* Pack the name in the end of the buffer */
+               ptr -= tmpname->ln_namelen;
+               if (ptr - 1 <= pli->pli_path)
+                       GOTO(out, rc = -EOVERFLOW);
+               strncpy(ptr, tmpname->ln_name, tmpname->ln_namelen);
+               *(--ptr) = '/';
+
+               /* Store the parent fid for historic lookup */
+               if (++pli->pli_fidcount >= MAX_PATH_DEPTH)
+                       GOTO(out, rc = -EOVERFLOW);
+               pli->pli_fids[pli->pli_fidcount] = *tmpfid;
+       }
+
+remote_out:
+       ptr++; /* skip leading / */
+       memmove(pli->pli_path, ptr, pli->pli_path + pli->pli_pathlen - ptr);
+
+       EXIT;
+out:
+       return rc;
+}
+
+/* Returns the full path to this fid, as of changelog record recno. */
+static int mdt_path(struct mdt_thread_info *info, struct mdt_object *obj,
+                   char *path, int pathlen, __u64 *recno, int *linkno,
+                   struct lu_fid *fid)
+{
+       struct mdt_device       *mdt = info->mti_mdt;
+       struct path_lookup_info *pli;
+       int                     tries = 3;
+       int                     rc = -EAGAIN;
+       ENTRY;
+
+       if (pathlen < 3)
+               RETURN(-EOVERFLOW);
+
+       if (lu_fid_eq(&mdt->mdt_md_root_fid, mdt_object_fid(obj))) {
+               path[0] = '\0';
+               RETURN(0);
+       }
+
+       OBD_ALLOC_PTR(pli);
+       if (pli == NULL)
+               RETURN(-ENOMEM);
+
+       pli->pli_mdt_obj = obj;
+       pli->pli_recno = *recno;
+       pli->pli_path = path;
+       pli->pli_pathlen = pathlen;
+       pli->pli_linkno = *linkno;
+
+       /* Retry multiple times in case file is being moved */
+       while (tries-- && rc == -EAGAIN)
+               rc = mdt_path_current(info, pli);
+
+       /* return the last resolved fids to the client, so the client will
+        * build the left path on another MDT for remote object */
+       *fid = pli->pli_fids[pli->pli_fidcount];
+
+       *recno = pli->pli_currec;
+       /* Return next link index to caller */
+       *linkno = pli->pli_linkno;
+
+       OBD_FREE_PTR(pli);
+
+       RETURN(rc);
 }
 
-static int mdt_fid2path(const struct lu_env *env, struct mdt_device *mdt,
-               struct getinfo_fid2path *fp)
+static int mdt_fid2path(struct mdt_thread_info *info,
+                       struct getinfo_fid2path *fp)
 {
+       struct mdt_device *mdt = info->mti_mdt;
        struct mdt_object *obj;
-       struct obd_device *obd = mdt2obd_dev(mdt);
        int    rc;
        ENTRY;
 
@@ -5329,119 +5447,156 @@ static int mdt_fid2path(const struct lu_env *env, struct mdt_device *mdt,
        if (!fid_is_sane(&fp->gf_fid))
                RETURN(-EINVAL);
 
-       if (!fid_is_norm(&fp->gf_fid) && !fid_is_igif(&fp->gf_fid)) {
+       if (!fid_is_namespace_visible(&fp->gf_fid)) {
                CWARN("%s: "DFID" is invalid, sequence should be "
-                       ">= "LPX64"\n", obd->obd_name,
-                       PFID(&fp->gf_fid), (__u64)FID_SEQ_NORMAL);
+                     ">= "LPX64"\n", mdt_obd_name(mdt),
+                     PFID(&fp->gf_fid), (__u64)FID_SEQ_NORMAL);
                RETURN(-EINVAL);
        }
 
-       obj = mdt_object_find(env, mdt, &fp->gf_fid);
+       obj = mdt_object_find(info->mti_env, mdt, &fp->gf_fid);
        if (obj == NULL || IS_ERR(obj)) {
                CDEBUG(D_IOCTL, "no object "DFID": %ld\n", PFID(&fp->gf_fid),
-                       PTR_ERR(obj));
+                      PTR_ERR(obj));
                RETURN(-EINVAL);
        }
 
-       rc = lu_object_exists(&obj->mot_obj.mo_lu);
-       if (rc <= 0) {
-               if (rc == -1)
-                       rc = -EREMOTE;
-               else
-                       rc = -ENOENT;
-               mdt_object_put(env, obj);
+       if (mdt_object_remote(obj))
+               rc = -EREMOTE;
+       else if (!mdt_object_exists(obj))
+               rc = -ENOENT;
+       else
+               rc = 0;
+
+       if (rc < 0) {
+               mdt_object_put(info->mti_env, obj);
                CDEBUG(D_IOCTL, "nonlocal object "DFID": %d\n",
-                       PFID(&fp->gf_fid), rc);
+                      PFID(&fp->gf_fid), rc);
                RETURN(rc);
        }
 
-       rc = mo_path(env, md_object_next(&obj->mot_obj), fp->gf_path,
-                       fp->gf_pathlen, &fp->gf_recno, &fp->gf_linkno);
-       mdt_object_put(env, obj);
+       rc = mdt_path(info, obj, fp->gf_path, fp->gf_pathlen, &fp->gf_recno,
+                     &fp->gf_linkno, &fp->gf_fid);
+
+       CDEBUG(D_INFO, "fid "DFID", path %s recno "LPX64" linkno %u\n",
+              PFID(&fp->gf_fid), fp->gf_path, fp->gf_recno, fp->gf_linkno);
+
+       mdt_object_put(info->mti_env, obj);
 
        RETURN(rc);
 }
 
-int mdt_get_info(struct mdt_thread_info *info)
+static int mdt_rpc_fid2path(struct mdt_thread_info *info, void *key,
+                           void *val, int vallen)
 {
-        struct ptlrpc_request *req = mdt_info_req(info);
-        char *key;
-        int keylen;
-        __u32 *vallen;
-        void *valout;
-        int rc;
-        ENTRY;
+       struct getinfo_fid2path *fpout, *fpin;
+       int rc = 0;
 
-        key = req_capsule_client_get(info->mti_pill, &RMF_GETINFO_KEY);
-        if (key == NULL) {
-                CDEBUG(D_IOCTL, "No GETINFO key");
-                RETURN(-EFAULT);
-        }
-        keylen = req_capsule_get_size(info->mti_pill, &RMF_GETINFO_KEY,
-                                      RCL_CLIENT);
+       fpin = key + cfs_size_round(sizeof(KEY_FID2PATH));
+       fpout = val;
 
-        vallen = req_capsule_client_get(info->mti_pill, &RMF_GETINFO_VALLEN);
-        if (vallen == NULL) {
-                CDEBUG(D_IOCTL, "Unable to get RMF_GETINFO_VALLEN buffer");
-                RETURN(-EFAULT);
-        }
+       if (ptlrpc_req_need_swab(info->mti_pill->rc_req))
+               lustre_swab_fid2path(fpin);
 
-        req_capsule_set_size(info->mti_pill, &RMF_GETINFO_VAL, RCL_SERVER,
-                             *vallen);
-        rc = req_capsule_server_pack(info->mti_pill);
-        valout = req_capsule_server_get(info->mti_pill, &RMF_GETINFO_VAL);
-        if (valout == NULL) {
-                CDEBUG(D_IOCTL, "Unable to get get-info RPC out buffer");
-                RETURN(-EFAULT);
-        }
+       memcpy(fpout, fpin, sizeof(*fpin));
+       if (fpout->gf_pathlen != vallen - sizeof(*fpin))
+               RETURN(-EINVAL);
 
-        if (KEY_IS(KEY_FID2PATH))
-                rc = mdt_rpc_fid2path(info, key, valout, *vallen);
-        else
-                rc = -EINVAL;
+       rc = mdt_fid2path(info, fpout);
+       RETURN(rc);
+}
+
+int mdt_get_info(struct tgt_session_info *tsi)
+{
+       char    *key;
+       int      keylen;
+       __u32   *vallen;
+       void    *valout;
+       int      rc;
 
-        lustre_msg_set_status(req->rq_repmsg, rc);
+       ENTRY;
 
-        RETURN(rc);
+       key = req_capsule_client_get(tsi->tsi_pill, &RMF_GETINFO_KEY);
+       if (key == NULL) {
+               CDEBUG(D_IOCTL, "No GETINFO key");
+               RETURN(err_serious(-EFAULT));
+       }
+       keylen = req_capsule_get_size(tsi->tsi_pill, &RMF_GETINFO_KEY,
+                                     RCL_CLIENT);
+
+       vallen = req_capsule_client_get(tsi->tsi_pill, &RMF_GETINFO_VALLEN);
+       if (vallen == NULL) {
+               CDEBUG(D_IOCTL, "Unable to get RMF_GETINFO_VALLEN buffer");
+               RETURN(err_serious(-EFAULT));
+       }
+
+       req_capsule_set_size(tsi->tsi_pill, &RMF_GETINFO_VAL, RCL_SERVER,
+                            *vallen);
+       rc = req_capsule_server_pack(tsi->tsi_pill);
+       if (rc)
+               RETURN(err_serious(rc));
+
+       valout = req_capsule_server_get(tsi->tsi_pill, &RMF_GETINFO_VAL);
+       if (valout == NULL) {
+               CDEBUG(D_IOCTL, "Unable to get get-info RPC out buffer");
+               RETURN(err_serious(-EFAULT));
+       }
+
+       if (KEY_IS(KEY_FID2PATH)) {
+               struct mdt_thread_info  *info = tsi2mdt_info(tsi);
+
+               rc = mdt_rpc_fid2path(info, key, valout, *vallen);
+               mdt_thread_info_fini(info);
+       } else {
+               rc = -EINVAL;
+       }
+       RETURN(rc);
 }
 
 /* Pass the ioc down */
 static int mdt_ioc_child(struct lu_env *env, struct mdt_device *mdt,
-                         unsigned int cmd, int len, void *data)
+                        unsigned int cmd, int len, void *data)
 {
-        struct lu_context ioctl_session;
-        struct md_device *next = mdt->mdt_child;
-        int rc;
-        ENTRY;
+       struct lu_context ioctl_session;
+       struct md_device *next = mdt->mdt_child;
+       int rc;
+       ENTRY;
 
-        rc = lu_context_init(&ioctl_session, LCT_SESSION);
-        if (rc)
-                RETURN(rc);
-        ioctl_session.lc_thread = (struct ptlrpc_thread *)cfs_current();
-        lu_context_enter(&ioctl_session);
-        env->le_ses = &ioctl_session;
+        rc = lu_context_init(&ioctl_session, LCT_SERVER_SESSION);
+       if (rc)
+               RETURN(rc);
+       ioctl_session.lc_thread = (struct ptlrpc_thread *)current;
+       lu_context_enter(&ioctl_session);
+       env->le_ses = &ioctl_session;
 
-        LASSERT(next->md_ops->mdo_iocontrol);
-        rc = next->md_ops->mdo_iocontrol(env, next, cmd, len, data);
+       LASSERT(next->md_ops->mdo_iocontrol);
+       rc = next->md_ops->mdo_iocontrol(env, next, cmd, len, data);
 
-        lu_context_exit(&ioctl_session);
-        lu_context_fini(&ioctl_session);
-        RETURN(rc);
+       lu_context_exit(&ioctl_session);
+       lu_context_fini(&ioctl_session);
+       RETURN(rc);
 }
 
 static int mdt_ioc_version_get(struct mdt_thread_info *mti, void *karg)
 {
-        struct obd_ioctl_data *data = karg;
-        struct lu_fid *fid = (struct lu_fid *)data->ioc_inlbuf1;
-        __u64 version;
-        struct mdt_object *obj;
-        struct mdt_lock_handle  *lh;
-        int rc;
-        ENTRY;
+       struct obd_ioctl_data *data = karg;
+       struct lu_fid *fid;
+       __u64 version;
+       struct mdt_object *obj;
+       struct mdt_lock_handle  *lh;
+       int rc;
+       ENTRY;
 
-        CDEBUG(D_IOCTL, "getting version for "DFID"\n", PFID(fid));
-        if (!fid_is_sane(fid))
-                RETURN(-EINVAL);
+       if (data->ioc_inlbuf1 == NULL || data->ioc_inllen1 != sizeof(*fid) ||
+           data->ioc_inlbuf2 == NULL || data->ioc_inllen2 != sizeof(version))
+               RETURN(-EINVAL);
+
+       fid = (struct lu_fid *)data->ioc_inlbuf1;
+
+       if (!fid_is_sane(fid))
+               RETURN(-EINVAL);
+
+       CDEBUG(D_IOCTL, "getting version for "DFID"\n", PFID(fid));
 
         lh = &mti->mti_lh[MDT_LH_PARENT];
         mdt_lock_reg_init(lh, LCK_CR);
@@ -5450,24 +5605,23 @@ static int mdt_ioc_version_get(struct mdt_thread_info *mti, void *karg)
         if (IS_ERR(obj))
                 RETURN(PTR_ERR(obj));
 
-        rc = mdt_object_exists(obj);
-        if (rc < 0) {
-                rc = -EREMOTE;
-                /**
-                 * before calling version get the correct MDS should be
-                 * fid, this is error to find remote object here
-                 */
-                CERROR("nonlocal object "DFID"\n", PFID(fid));
-        } else if (rc == 0) {
-                *(__u64 *)data->ioc_inlbuf2 = ENOENT_VERSION;
-                rc = -ENOENT;
-        } else {
-                version = dt_version_get(mti->mti_env, mdt_obj2dt(obj));
-               *(__u64 *)data->ioc_inlbuf2 = version;
-                rc = 0;
-        }
-        mdt_object_unlock_put(mti, obj, lh, 1);
-        RETURN(rc);
+       if (mdt_object_remote(obj)) {
+               rc = -EREMOTE;
+               /**
+                * before calling version get the correct MDS should be
+                * fid, this is error to find remote object here
+                */
+               CERROR("nonlocal object "DFID"\n", PFID(fid));
+       } else if (!mdt_object_exists(obj)) {
+               *(__u64 *)data->ioc_inlbuf2 = ENOENT_VERSION;
+               rc = -ENOENT;
+       } else {
+               version = dt_version_get(mti->mti_env, mdt_obj2dt(obj));
+              *(__u64 *)data->ioc_inlbuf2 = version;
+               rc = 0;
+       }
+       mdt_object_unlock_put(mti, obj, lh, 1);
+       RETURN(rc);
 }
 
 /* ioctls on obd dev */
@@ -5493,29 +5647,45 @@ static int mdt_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
         case OBD_IOC_SET_READONLY:
                 rc = dt->dd_ops->dt_ro(&env, dt);
                 break;
-        case OBD_IOC_ABORT_RECOVERY:
-                CERROR("Aborting recovery for device %s\n", obd->obd_name);
-                target_stop_recovery_thread(obd);
-                rc = 0;
-                break;
+       case OBD_IOC_ABORT_RECOVERY:
+               CERROR("%s: Aborting recovery for device\n", mdt_obd_name(mdt));
+               target_stop_recovery_thread(obd);
+               rc = 0;
+               break;
         case OBD_IOC_CHANGELOG_REG:
         case OBD_IOC_CHANGELOG_DEREG:
         case OBD_IOC_CHANGELOG_CLEAR:
                 rc = mdt_ioc_child(&env, mdt, cmd, len, karg);
                 break;
-       case OBD_IOC_START_LFSCK:
-       case OBD_IOC_STOP_LFSCK: {
+       case OBD_IOC_START_LFSCK: {
                struct md_device *next = mdt->mdt_child;
                struct obd_ioctl_data *data = karg;
+               struct lfsck_start_param lsp;
 
                if (unlikely(data == NULL)) {
                        rc = -EINVAL;
                        break;
                }
 
-               rc = next->md_ops->mdo_iocontrol(&env, next, cmd,
-                                                data->ioc_inllen1,
-                                                data->ioc_inlbuf1);
+               lsp.lsp_start = (struct lfsck_start *)(data->ioc_inlbuf1);
+               lsp.lsp_index_valid = 0;
+               rc = next->md_ops->mdo_iocontrol(&env, next, cmd, 0, &lsp);
+               break;
+       }
+       case OBD_IOC_STOP_LFSCK: {
+               struct md_device        *next = mdt->mdt_child;
+               struct obd_ioctl_data   *data = karg;
+               struct lfsck_stop        stop;
+
+               stop.ls_status = LS_STOPPED;
+               /* Old lfsck utils may pass NULL @stop. */
+               if (data->ioc_inlbuf1 == NULL)
+                       stop.ls_flags = 0;
+               else
+                       stop.ls_flags =
+                       ((struct lfsck_stop *)(data->ioc_inlbuf1))->ls_flags;
+
+               rc = next->md_ops->mdo_iocontrol(&env, next, cmd, 0, &stop);
                break;
        }
         case OBD_IOC_GET_OBJ_VERSION: {
@@ -5529,11 +5699,20 @@ static int mdt_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
                 rc = mdt_ioc_version_get(mti, karg);
                 break;
         }
-        default:
-                CERROR("Not supported cmd = %d for device %s\n",
-                       cmd, obd->obd_name);
-                rc = -EOPNOTSUPP;
-        }
+       case OBD_IOC_CATLOGLIST: {
+               struct mdt_thread_info *mti;
+
+               mti = lu_context_key_get(&env.le_ctx, &mdt_thread_key);
+               lu_local_obj_fid(&mti->mti_tmp_fid1, LLOG_CATALOGS_OID);
+               rc = llog_catalog_list(&env, mdt->mdt_bottom, 0, karg,
+                                      &mti->mti_tmp_fid1);
+               break;
+        }
+       default:
+               rc = -EOPNOTSUPP;
+               CERROR("%s: Not supported cmd = %d, rc = %d\n",
+                       mdt_obd_name(mdt), cmd, rc);
+       }
 
         lu_env_fini(&env);
         RETURN(rc);
@@ -5587,12 +5766,13 @@ static struct lu_device* mdt_device_fini(const struct lu_env *env,
 static struct lu_device *mdt_device_free(const struct lu_env *env,
                                          struct lu_device *d)
 {
-        struct mdt_device *m = mdt_dev(d);
-        ENTRY;
+       struct mdt_device *m = mdt_dev(d);
+       ENTRY;
 
-        md_device_fini(&m->mdt_md_dev);
-        OBD_FREE_PTR(m);
-        RETURN(NULL);
+       lu_device_fini(&m->mdt_lu_dev);
+       OBD_FREE_PTR(m);
+
+       RETURN(NULL);
 }
 
 static struct lu_device *mdt_device_alloc(const struct lu_env *env,
@@ -5606,7 +5786,7 @@ static struct lu_device *mdt_device_alloc(const struct lu_env *env,
         if (m != NULL) {
                 int rc;
 
-                l = &m->mdt_md_dev.md_lu_dev;
+               l = &m->mdt_lu_dev;
                 rc = mdt_init0(env, m, t, cfg);
                 if (rc != 0) {
                         mdt_device_free(env, l);
@@ -5701,6 +5881,10 @@ static int __init mdt_mod_init(void)
        struct lprocfs_static_vars lvars;
        int rc;
 
+       CLASSERT(sizeof("0x0123456789ABCDEF:0x01234567:0x01234567") ==
+                FID_NOBRACE_LEN + 1);
+       CLASSERT(sizeof("[0x0123456789ABCDEF:0x01234567:0x01234567]") ==
+                FID_LEN + 1);
        rc = lu_kmem_init(mdt_caches);
        if (rc)
                return rc;
@@ -5710,9 +5894,11 @@ static int __init mdt_mod_init(void)
                GOTO(lu_fini, rc);
 
        lprocfs_mdt_init_vars(&lvars);
-       rc = class_register_type(&mdt_obd_device_ops, NULL,
-                                lvars.module_vars, LUSTRE_MDT_NAME,
-                                &mdt_device_type);
+       rc = class_register_type(&mdt_obd_device_ops, NULL, NULL,
+#ifndef HAVE_ONLY_PROCFS_SEQ
+                               lvars.module_vars,
+#endif
+                               LUSTRE_MDT_NAME, &mdt_device_type);
        if (rc)
                GOTO(mds_fini, rc);
 lu_fini: