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LU-11135 mdt: LASSERT(lu_object_exists(o)) fails
[fs/lustre-release.git] / lustre / mdt / mdt_reint.c
index 2ad5259..62308a8 100644 (file)
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
@@ -27,7 +23,7 @@
  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2011, 2015, Intel Corporation.
+ * Copyright (c) 2011, 2017, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -65,14 +61,15 @@ static inline void mdt_reint_init_ma(struct mdt_thread_info *info,
 static void mdt_obj_version_get(struct mdt_thread_info *info,
                                 struct mdt_object *o, __u64 *version)
 {
-        LASSERT(o);
+       LASSERT(o);
+
        if (mdt_object_exists(o) && !mdt_object_remote(o) &&
            !fid_is_obf(mdt_object_fid(o)))
-                *version = dt_version_get(info->mti_env, mdt_obj2dt(o));
-        else
-                *version = ENOENT_VERSION;
-        CDEBUG(D_INODE, "FID "DFID" version is "LPX64"\n",
-               PFID(mdt_object_fid(o)), *version);
+               *version = dt_version_get(info->mti_env, mdt_obj2dt(o));
+       else
+               *version = ENOENT_VERSION;
+       CDEBUG(D_INODE, "FID "DFID" version is %#llx\n",
+              PFID(mdt_object_fid(o)), *version);
 }
 
 /**
@@ -100,7 +97,7 @@ static int mdt_version_check(struct ptlrpc_request *req,
                spin_unlock(&req->rq_export->exp_lock);
                RETURN(-EOVERFLOW);
        } else if (pre_ver[idx] != version) {
-               CDEBUG(D_INODE, "Version mismatch "LPX64" != "LPX64"\n",
+               CDEBUG(D_INODE, "Version mismatch %#llx != %#llx\n",
                       pre_ver[idx], version);
                spin_lock(&req->rq_export->exp_lock);
                req->rq_export->exp_vbr_failed = 1;
@@ -292,6 +289,123 @@ static int mdt_remote_permission(struct mdt_thread_info *info)
        return 0;
 }
 
+static int mdt_unlock_slaves(struct mdt_thread_info *mti,
+                            struct mdt_object *obj,
+                            struct ldlm_enqueue_info *einfo,
+                            int decref)
+{
+       union ldlm_policy_data *policy = &mti->mti_policy;
+       struct mdt_lock_handle *lh = &mti->mti_lh[MDT_LH_LOCAL];
+       struct lustre_handle_array *slave_locks = einfo->ei_cbdata;
+       int i;
+
+       LASSERT(S_ISDIR(obj->mot_header.loh_attr));
+       LASSERT(slave_locks);
+
+       memset(policy, 0, sizeof(*policy));
+       policy->l_inodebits.bits = einfo->ei_inodebits;
+       mdt_lock_handle_init(lh);
+       mdt_lock_reg_init(lh, einfo->ei_mode);
+       for (i = 0; i < slave_locks->ha_count; i++) {
+               if (test_bit(i, (void *)slave_locks->ha_map))
+                       lh->mlh_rreg_lh = slave_locks->ha_handles[i];
+               else
+                       lh->mlh_reg_lh = slave_locks->ha_handles[i];
+               mdt_object_unlock(mti, NULL, lh, decref);
+               slave_locks->ha_handles[i].cookie = 0ull;
+       }
+
+       return mo_object_unlock(mti->mti_env, mdt_object_child(obj), einfo,
+                               policy);
+}
+
+static inline int mdt_object_striped(struct mdt_thread_info *mti,
+                                    struct mdt_object *obj)
+{
+       int rc;
+
+       if (!S_ISDIR(obj->mot_header.loh_attr))
+               return 0;
+
+       rc = mo_xattr_get(mti->mti_env, mdt_object_child(obj), &LU_BUF_NULL,
+                         XATTR_NAME_LMV);
+       if (rc <= 0)
+               return rc == -ENODATA ? 0 : rc;
+
+       return 1;
+}
+
+/**
+ * Lock slave stripes if necessary, the lock handles of slave stripes
+ * will be stored in einfo->ei_cbdata.
+ **/
+static int mdt_lock_slaves(struct mdt_thread_info *mti, struct mdt_object *obj,
+                          enum ldlm_mode mode, __u64 ibits,
+                          struct ldlm_enqueue_info *einfo)
+{
+       union ldlm_policy_data *policy = &mti->mti_policy;
+
+       LASSERT(S_ISDIR(obj->mot_header.loh_attr));
+
+       einfo->ei_type = LDLM_IBITS;
+       einfo->ei_mode = mode;
+       einfo->ei_cb_bl = mdt_remote_blocking_ast;
+       einfo->ei_cb_local_bl = mdt_blocking_ast;
+       einfo->ei_cb_cp = ldlm_completion_ast;
+       einfo->ei_enq_slave = 1;
+       einfo->ei_namespace = mti->mti_mdt->mdt_namespace;
+       einfo->ei_inodebits = ibits;
+       memset(policy, 0, sizeof(*policy));
+       policy->l_inodebits.bits = ibits;
+
+       return mo_object_lock(mti->mti_env, mdt_object_child(obj), NULL, einfo,
+                             policy);
+}
+
+static inline int mdt_reint_striped_lock(struct mdt_thread_info *info,
+                                        struct mdt_object *o,
+                                        struct mdt_lock_handle *lh,
+                                        __u64 ibits,
+                                        struct ldlm_enqueue_info *einfo,
+                                        bool cos_incompat)
+{
+       int rc;
+
+       LASSERT(!mdt_object_remote(o));
+
+       memset(einfo, 0, sizeof(*einfo));
+
+       rc = mdt_reint_object_lock(info, o, lh, ibits, cos_incompat);
+       if (rc)
+               return rc;
+
+       rc = mdt_object_striped(info, o);
+       if (rc != 1) {
+               if (rc < 0)
+                       mdt_object_unlock(info, o, lh, rc);
+               return rc;
+       }
+
+       rc = mdt_lock_slaves(info, o, lh->mlh_reg_mode, ibits, einfo);
+       if (rc) {
+               mdt_object_unlock(info, o, lh, rc);
+               if (rc == -EIO && OBD_FAIL_CHECK(OBD_FAIL_LFSCK_BAD_SLAVE_NAME))
+                       rc = 0;
+       }
+
+       return rc;
+}
+
+static inline void
+mdt_reint_striped_unlock(struct mdt_thread_info *info, struct mdt_object *o,
+                        struct mdt_lock_handle *lh,
+                        struct ldlm_enqueue_info *einfo, int decref)
+{
+       if (einfo->ei_cbdata)
+               mdt_unlock_slaves(info, o, einfo, decref);
+       mdt_object_unlock(info, o, lh, decref);
+}
+
 /*
  * VBR: we save three versions in reply:
  * 0 - parent. Check that parent version is the same during replay.
@@ -300,17 +414,17 @@ static int mdt_remote_permission(struct mdt_thread_info *info)
  * 2 - child. Version of child by FID. Must be ENOENT. It is mostly sanity
  * check.
  */
-static int mdt_md_create(struct mdt_thread_info *info)
+static int mdt_create(struct mdt_thread_info *info)
 {
-        struct mdt_device       *mdt = info->mti_mdt;
-        struct mdt_object       *parent;
-        struct mdt_object       *child;
-        struct mdt_lock_handle  *lh;
-        struct mdt_body         *repbody;
-        struct md_attr          *ma = &info->mti_attr;
-        struct mdt_reint_record *rr = &info->mti_rr;
-        int rc;
-        ENTRY;
+       struct mdt_device       *mdt = info->mti_mdt;
+       struct mdt_object       *parent;
+       struct mdt_object       *child;
+       struct mdt_lock_handle  *lh;
+       struct mdt_body         *repbody;
+       struct md_attr          *ma = &info->mti_attr;
+       struct mdt_reint_record *rr = &info->mti_rr;
+       int rc;
+       ENTRY;
 
        DEBUG_REQ(D_INODE, mdt_info_req(info), "Create  ("DNAME"->"DFID") "
                  "in "DFID,
@@ -357,153 +471,96 @@ static int mdt_md_create(struct mdt_thread_info *info)
        mdt_enoent_version_save(info, 1);
 
        child = mdt_object_new(info->mti_env, mdt, rr->rr_fid2);
-        if (likely(!IS_ERR(child))) {
-                struct md_object *next = mdt_object_child(parent);
-
-               rc = mdt_remote_permission(info);
-               if (rc != 0)
-                       GOTO(out_put_child, rc);
-
-               ma->ma_need = MA_INODE;
-                ma->ma_valid = 0;
-
-                mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
-                               OBD_FAIL_MDS_REINT_CREATE_WRITE);
+       if (unlikely(IS_ERR(child)))
+               GOTO(unlock_parent, rc = PTR_ERR(child));
 
-                /* Version of child will be updated on disk. */
-               tgt_vbr_obj_set(info->mti_env, mdt_obj2dt(child));
-                rc = mdt_version_get_check_save(info, child, 2);
-                if (rc)
-                        GOTO(out_put_child, rc);
+       rc = mdt_remote_permission(info);
+       if (rc != 0)
+               GOTO(put_child, rc);
 
-                /* Let lower layer know current lock mode. */
-                info->mti_spec.sp_cr_mode =
-                        mdt_dlm_mode2mdl_mode(lh->mlh_pdo_mode);
+       ma->ma_need = MA_INODE;
+       ma->ma_valid = 0;
 
-               /*
-                * Do not perform lookup sanity check. We know that name does
-                * not exist.
-                */
-               info->mti_spec.sp_cr_lookup = 0;
-                info->mti_spec.sp_feat = &dt_directory_features;
-
-               rc = mdo_create(info->mti_env, next, &rr->rr_name,
-                               mdt_object_child(child), &info->mti_spec, ma);
-               if (rc == 0)
-                       rc = mdt_attr_get_complex(info, child, ma);
-
-               if (rc == 0) {
-                       /* Return fid & attr to client. */
-                       if (ma->ma_valid & MA_INODE)
-                               mdt_pack_attr2body(info, repbody, &ma->ma_attr,
-                                                  mdt_object_fid(child));
-               }
-out_put_child:
-               mdt_object_put(info->mti_env, child);
-       } else {
-               rc = PTR_ERR(child);
-       }
-unlock_parent:
-       mdt_object_unlock(info, parent, lh, rc);
-put_parent:
-       mdt_object_put(info->mti_env, parent);
-       RETURN(rc);
-}
+       mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
+                       OBD_FAIL_MDS_REINT_CREATE_WRITE);
 
-static int mdt_unlock_slaves(struct mdt_thread_info *mti,
-                            struct mdt_object *obj, __u64 ibits,
-                            struct mdt_lock_handle *s0_lh,
-                            struct mdt_object *s0_obj,
-                            struct ldlm_enqueue_info *einfo)
-{
-       union ldlm_policy_data *policy = &mti->mti_policy;
-       int rc;
-       ENTRY;
+       /* Version of child will be updated on disk. */
+       tgt_vbr_obj_set(info->mti_env, mdt_obj2dt(child));
+       rc = mdt_version_get_check_save(info, child, 2);
+       if (rc)
+               GOTO(put_child, rc);
 
-       if (!S_ISDIR(obj->mot_header.loh_attr))
-               RETURN(0);
+       /* Let lower layer know current lock mode. */
+       info->mti_spec.sp_cr_mode = mdt_dlm_mode2mdl_mode(lh->mlh_pdo_mode);
 
-       /* Unlock stripe 0 */
-       if (s0_lh != NULL && lustre_handle_is_used(&s0_lh->mlh_reg_lh)) {
-               LASSERT(s0_obj != NULL);
-               mdt_object_unlock_put(mti, s0_obj, s0_lh, 1);
-       }
+       /*
+        * Do not perform lookup sanity check. We know that name does
+        * not exist.
+        */
+       info->mti_spec.sp_cr_lookup = 0;
+       info->mti_spec.sp_feat = &dt_directory_features;
 
-       memset(policy, 0, sizeof(*policy));
-       policy->l_inodebits.bits = ibits;
+       rc = mdo_create(info->mti_env, mdt_object_child(parent), &rr->rr_name,
+                       mdt_object_child(child), &info->mti_spec, ma);
+       if (rc == 0)
+               rc = mdt_attr_get_complex(info, child, ma);
 
-       rc = mo_object_unlock(mti->mti_env, mdt_object_child(obj), einfo,
-                             policy);
-       RETURN(rc);
-}
+       if (rc < 0)
+               GOTO(put_child, rc);
 
-/**
- * Lock slave stripes if necessary, the lock handles of slave stripes
- * will be stored in einfo->ei_cbdata.
- **/
-static int mdt_lock_slaves(struct mdt_thread_info *mti, struct mdt_object *obj,
-                          enum ldlm_mode mode, __u64 ibits,
-                          struct mdt_lock_handle *s0_lh,
-                          struct mdt_object **s0_objp,
-                          struct ldlm_enqueue_info *einfo)
-{
-       union ldlm_policy_data *policy = &mti->mti_policy;
-       struct lu_buf *buf = &mti->mti_buf;
-       struct lmv_mds_md_v1 *lmv;
-       struct lu_fid *fid = &mti->mti_tmp_fid1;
-       int rc;
-       ENTRY;
+       /*
+        * On DNE, we need to eliminate dependey between 'mkdir a' and
+        * 'mkdir a/b' if b is a striped directory, to achieve this, two
+        * things are done below:
+        * 1. save child and slaves lock.
+        * 2. if the child is a striped directory, relock parent so to
+        *    compare against with COS locks to ensure parent was
+        *    committed to disk.
+        */
+       if (mdt_slc_is_enabled(mdt) && S_ISDIR(ma->ma_attr.la_mode)) {
+               struct mdt_lock_handle *lhc;
+               struct ldlm_enqueue_info *einfo = &info->mti_einfo;
+               bool cos_incompat;
 
-       if (!S_ISDIR(obj->mot_header.loh_attr))
-               RETURN(0);
+               rc = mdt_object_striped(info, child);
+               if (rc < 0)
+                       GOTO(put_child, rc);
 
-       buf->lb_buf = mti->mti_xattr_buf;
-       buf->lb_len = sizeof(mti->mti_xattr_buf);
-       rc = mo_xattr_get(mti->mti_env, mdt_object_child(obj), buf,
-                         XATTR_NAME_LMV);
-       if (rc == -ERANGE) {
-               rc = mdt_big_xattr_get(mti, obj, XATTR_NAME_LMV);
-               if (rc > 0) {
-                       buf->lb_buf = mti->mti_big_lmm;
-                       buf->lb_len = mti->mti_big_lmmsize;
+               cos_incompat = rc;
+               if (cos_incompat) {
+                       if (!mdt_object_remote(parent)) {
+                               mdt_object_unlock(info, parent, lh, 1);
+                               mdt_lock_pdo_init(lh, LCK_PW, &rr->rr_name);
+                               rc = mdt_reint_object_lock(info, parent, lh,
+                                                          MDS_INODELOCK_UPDATE,
+                                                          true);
+                               if (rc)
+                                       GOTO(put_child, rc);
+                       }
                }
-       }
 
-       if (rc == -ENODATA || rc == -ENOENT)
-               RETURN(0);
-
-       if (rc <= 0)
-               RETURN(rc);
+               lhc = &info->mti_lh[MDT_LH_CHILD];
+               mdt_lock_handle_init(lhc);
+               mdt_lock_reg_init(lhc, LCK_PW);
+               rc = mdt_reint_striped_lock(info, child, lhc,
+                                           MDS_INODELOCK_UPDATE, einfo,
+                                           cos_incompat);
+               if (rc)
+                       GOTO(put_child, rc);
 
-       lmv = buf->lb_buf;
-       if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_V1)
-               RETURN(-EINVAL);
-
-       fid_le_to_cpu(fid, &lmv->lmv_stripe_fids[0]);
-       if (!lu_fid_eq(fid, mdt_object_fid(obj))) {
-               /* Except migrating object, whose 0_stripe and master
-                * object are the same object, 0_stripe and master
-                * object are different, though they are in the same
-                * MDT, to avoid adding osd_object_lock here, so we
-                * will enqueue the stripe0 lock in MDT0 for now */
-               *s0_objp = mdt_object_find_lock(mti, fid, s0_lh, ibits);
-               if (IS_ERR(*s0_objp))
-                       RETURN(PTR_ERR(*s0_objp));
+               mdt_reint_striped_unlock(info, child, lhc, einfo, rc);
        }
 
-       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_local_bl = mdt_blocking_ast;
-       einfo->ei_cb_cp = ldlm_completion_ast;
-       einfo->ei_enq_slave = 1;
-       einfo->ei_namespace = mti->mti_mdt->mdt_namespace;
-       memset(policy, 0, sizeof(*policy));
-       policy->l_inodebits.bits = ibits;
-
-       rc = mo_object_lock(mti->mti_env, mdt_object_child(obj), NULL, einfo,
-                           policy);
+       /* Return fid & attr to client. */
+       if (ma->ma_valid & MA_INODE)
+               mdt_pack_attr2body(info, repbody, &ma->ma_attr,
+                                  mdt_object_fid(child));
+put_child:
+       mdt_object_put(info->mti_env, child);
+unlock_parent:
+       mdt_object_unlock(info, parent, lh, rc);
+put_parent:
+       mdt_object_put(info->mti_env, parent);
        RETURN(rc);
 }
 
@@ -511,16 +568,22 @@ static int mdt_attr_set(struct mdt_thread_info *info, struct mdt_object *mo,
                        struct md_attr *ma)
 {
        struct mdt_lock_handle  *lh;
-       int do_vbr = ma->ma_attr.la_valid & (LA_MODE|LA_UID|LA_GID|LA_FLAGS);
+       int do_vbr = ma->ma_attr.la_valid &
+                       (LA_MODE | LA_UID | LA_GID | LA_PROJID | LA_FLAGS);
        __u64 lockpart = MDS_INODELOCK_UPDATE;
        struct ldlm_enqueue_info *einfo = &info->mti_einfo;
-       struct mdt_lock_handle  *s0_lh;
-       struct mdt_object       *s0_obj = NULL;
+       bool cos_incompat;
        int rc;
        ENTRY;
 
-        lh = &info->mti_lh[MDT_LH_PARENT];
-        mdt_lock_reg_init(lh, LCK_PW);
+       rc = mdt_object_striped(info, mo);
+       if (rc < 0)
+               RETURN(rc);
+
+       cos_incompat = rc;
+
+       lh = &info->mti_lh[MDT_LH_PARENT];
+       mdt_lock_reg_init(lh, LCK_PW);
 
        /* Even though the new MDT will grant PERM lock to the old
         * client, but the old client will almost ignore that during
@@ -529,51 +592,41 @@ static int mdt_attr_set(struct mdt_thread_info *info, struct mdt_object *mo,
        if (ma->ma_attr.la_valid & (LA_MODE|LA_UID|LA_GID))
                lockpart |= MDS_INODELOCK_LOOKUP | MDS_INODELOCK_PERM;
 
-       rc = mdt_object_lock(info, mo, lh, lockpart);
+       rc = mdt_reint_striped_lock(info, mo, lh, lockpart, einfo,
+                                   cos_incompat);
        if (rc != 0)
                RETURN(rc);
 
-       s0_lh = &info->mti_lh[MDT_LH_LOCAL];
-       mdt_lock_reg_init(s0_lh, LCK_PW);
-       rc = mdt_lock_slaves(info, mo, LCK_PW, lockpart, s0_lh, &s0_obj, einfo);
-       if (rc != 0)
-               GOTO(out_unlock, rc);
-
-        /* all attrs are packed into mti_attr in unpack_setattr */
-        mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
-                       OBD_FAIL_MDS_REINT_SETATTR_WRITE);
-
-        /* This is only for set ctime when rename's source is on remote MDS. */
-        if (unlikely(ma->ma_attr.la_valid == LA_CTIME))
-                ma->ma_attr_flags |= MDS_VTX_BYPASS;
+       /* all attrs are packed into mti_attr in unpack_setattr */
+       mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
+                      OBD_FAIL_MDS_REINT_SETATTR_WRITE);
 
-        /* VBR: update version if attr changed are important for recovery */
-        if (do_vbr) {
-                /* update on-disk version of changed object */
+       /* VBR: update version if attr changed are important for recovery */
+       if (do_vbr) {
+               /* update on-disk version of changed object */
                tgt_vbr_obj_set(info->mti_env, mdt_obj2dt(mo));
-                rc = mdt_version_get_check_save(info, mo, 0);
-                if (rc)
-                        GOTO(out_unlock, rc);
-        }
+               rc = mdt_version_get_check_save(info, mo, 0);
+               if (rc)
+                       GOTO(out_unlock, rc);
+       }
 
        /* Ensure constant striping during chown(). See LU-2789. */
-       if (ma->ma_attr.la_valid & (LA_UID|LA_GID))
+       if (ma->ma_attr.la_valid & (LA_UID|LA_GID|LA_PROJID))
                mutex_lock(&mo->mot_lov_mutex);
 
-        /* all attrs are packed into mti_attr in unpack_setattr */
-        rc = mo_attr_set(info->mti_env, mdt_object_child(mo), ma);
+       /* all attrs are packed into mti_attr in unpack_setattr */
+       rc = mo_attr_set(info->mti_env, mdt_object_child(mo), ma);
 
-       if (ma->ma_attr.la_valid & (LA_UID|LA_GID))
+       if (ma->ma_attr.la_valid & (LA_UID|LA_GID|LA_PROJID))
                mutex_unlock(&mo->mot_lov_mutex);
 
-        if (rc != 0)
-                GOTO(out_unlock, rc);
-
-        EXIT;
+       if (rc != 0)
+               GOTO(out_unlock, rc);
+       mdt_dom_obj_lvb_update(info->mti_env, mo, false);
+       EXIT;
 out_unlock:
-       mdt_unlock_slaves(info, mo, lockpart, s0_lh, s0_obj, einfo);
-        mdt_object_unlock(info, mo, lh, rc);
-        return rc;
+       mdt_reint_striped_unlock(info, mo, lh, einfo, rc);
+       return rc;
 }
 
 /**
@@ -600,20 +653,12 @@ int mdt_add_dirty_flag(struct mdt_thread_info *info, struct mdt_object *mo,
        /* If an up2date copy exists in the backend, add dirty flag */
        if ((ma->ma_valid & MA_HSM) && (ma->ma_hsm.mh_flags & HS_EXISTS)
            && !(ma->ma_hsm.mh_flags & (HS_DIRTY|HS_RELEASED))) {
-               struct mdt_lock_handle  *lh = &info->mti_lh[MDT_LH_CHILD];
-
                ma->ma_hsm.mh_flags |= HS_DIRTY;
 
-               mdt_lock_reg_init(lh, LCK_PW);
-               rc = mdt_object_lock(info, mo, lh, MDS_INODELOCK_XATTR);
-               if (rc != 0)
-                       RETURN(rc);
-
                rc = mdt_hsm_attr_set(info, mo, &ma->ma_hsm);
                if (rc)
                        CERROR("file attribute change error for "DFID": %d\n",
                                PFID(mdt_object_fid(mo)), rc);
-               mdt_object_unlock(info, mo, lh, rc);
        }
 
        RETURN(rc);
@@ -647,11 +692,30 @@ static int mdt_reint_setattr(struct mdt_thread_info *info,
        if (mdt_object_remote(mo))
                GOTO(out_put, rc = -EREMOTE);
 
-       if ((ma->ma_attr.la_valid & LA_SIZE) ||
-           (rr->rr_flags & MRF_OPEN_TRUNC)) {
+       if (ma->ma_attr.la_valid & LA_SIZE || rr->rr_flags & MRF_OPEN_TRUNC) {
                /* Check write access for the O_TRUNC case */
                if (mdt_write_read(mo) < 0)
                        GOTO(out_put, rc = -ETXTBSY);
+
+               /* LU-10286: compatibility check for FLR.
+                * Please check the comment in mdt_finish_open() for details */
+               if (!exp_connect_flr(info->mti_exp)) {
+                       rc = mdt_big_xattr_get(info, mo, XATTR_NAME_LOV);
+                       if (rc < 0 && rc != -ENODATA)
+                               GOTO(out_put, rc);
+
+                       if (rc > 0 && mdt_lmm_is_flr(info->mti_big_lmm))
+                               GOTO(out_put, rc = -EOPNOTSUPP);
+               }
+
+               /* For truncate, the file size sent from client
+                * is believable, but the blocks are incorrect,
+                * which makes the block size in LSOM attribute
+                * inconsisent with the real block size.
+                */
+               rc = mdt_lsom_update(info, mo, true);
+               if (rc)
+                       GOTO(out_put, rc);
        }
 
        if ((ma->ma_valid & MA_INODE) && ma->ma_attr.la_valid) {
@@ -659,21 +723,10 @@ static int mdt_reint_setattr(struct mdt_thread_info *info,
                        GOTO(out_put, rc = -EPROTO);
 
                rc = mdt_attr_set(info, mo, ma);
-                if (rc)
-                        GOTO(out_put, rc);
-       } else if ((ma->ma_valid & MA_LOV) && (ma->ma_valid & MA_INODE)) {
-               struct lu_buf *buf  = &info->mti_buf;
-
-               if (ma->ma_attr.la_valid != 0)
-                       GOTO(out_put, rc = -EPROTO);
-
-               buf->lb_buf = ma->ma_lmm;
-               buf->lb_len = ma->ma_lmm_size;
-               rc = mo_xattr_set(info->mti_env, mdt_object_child(mo),
-                                 buf, XATTR_NAME_LOV, 0);
                if (rc)
                        GOTO(out_put, rc);
-       } else if ((ma->ma_valid & MA_LMV) && (ma->ma_valid & MA_INODE)) {
+       } else if ((ma->ma_valid & (MA_LOV | MA_LMV)) &&
+                  (ma->ma_valid & MA_INODE)) {
                struct lu_buf *buf  = &info->mti_buf;
                struct mdt_lock_handle  *lh;
 
@@ -687,15 +740,21 @@ static int mdt_reint_setattr(struct mdt_thread_info *info,
                lh = &info->mti_lh[MDT_LH_PARENT];
                mdt_lock_reg_init(lh, LCK_PW);
 
-               rc = mdt_object_lock(info, mo, lh,
-                                    MDS_INODELOCK_XATTR);
+               rc = mdt_object_lock(info, mo, lh, MDS_INODELOCK_XATTR);
                if (rc != 0)
                        GOTO(out_put, rc);
 
-               buf->lb_buf = ma->ma_lmv;
-               buf->lb_len = ma->ma_lmv_size;
-               rc = mo_xattr_set(info->mti_env, mdt_object_child(mo),
-                                 buf, XATTR_NAME_DEFAULT_LMV, 0);
+               if (ma->ma_valid & MA_LOV) {
+                       buf->lb_buf = ma->ma_lmm;
+                       buf->lb_len = ma->ma_lmm_size;
+               } else {
+                       buf->lb_buf = ma->ma_lmv;
+                       buf->lb_len = ma->ma_lmv_size;
+               }
+               rc = mo_xattr_set(info->mti_env, mdt_object_child(mo), buf,
+                                 (ma->ma_valid & MA_LOV) ?
+                                       XATTR_NAME_LOV : XATTR_NAME_DEFAULT_LMV,
+                                 0);
 
                mdt_object_unlock(info, mo, lh, rc);
                if (rc)
@@ -716,11 +775,11 @@ static int mdt_reint_setattr(struct mdt_thread_info *info,
 
        mdt_pack_attr2body(info, repbody, &ma->ma_attr, mdt_object_fid(mo));
 
-        EXIT;
+       EXIT;
 out_put:
-        mdt_object_put(info->mti_env, mo);
+       mdt_object_put(info->mti_env, mo);
 out:
-        if (rc == 0)
+       if (rc == 0)
                mdt_counter_incr(req, LPROC_MDT_SETATTR);
 
         mdt_client_compatibility(info);
@@ -767,7 +826,7 @@ static int mdt_reint_create(struct mdt_thread_info *info,
                RETURN(err_serious(-EOPNOTSUPP));
        }
 
-       rc = mdt_md_create(info);
+       rc = mdt_create(info);
        RETURN(rc);
 }
 
@@ -776,22 +835,22 @@ static int mdt_reint_create(struct mdt_thread_info *info,
  * Version of child is getting and checking during its lookup. If
  */
 static int mdt_reint_unlink(struct mdt_thread_info *info,
-                            struct mdt_lock_handle *lhc)
+                           struct mdt_lock_handle *lhc)
 {
-        struct mdt_reint_record *rr = &info->mti_rr;
-        struct ptlrpc_request   *req = mdt_info_req(info);
-        struct md_attr          *ma = &info->mti_attr;
-        struct lu_fid           *child_fid = &info->mti_tmp_fid1;
-        struct mdt_object       *mp;
-        struct mdt_object       *mc;
-        struct mdt_lock_handle  *parent_lh;
-        struct mdt_lock_handle  *child_lh;
+       struct mdt_reint_record *rr = &info->mti_rr;
+       struct ptlrpc_request *req = mdt_info_req(info);
+       struct md_attr *ma = &info->mti_attr;
+       struct lu_fid *child_fid = &info->mti_tmp_fid1;
+       struct mdt_object *mp;
+       struct mdt_object *mc;
+       struct mdt_lock_handle *parent_lh;
+       struct mdt_lock_handle *child_lh;
        struct ldlm_enqueue_info *einfo = &info->mti_einfo;
-       struct mdt_lock_handle  *s0_lh = NULL;
-       struct mdt_object       *s0_obj = NULL;
-       __u64                   lock_ibits;
-       int                     rc;
-       int                     no_name = 0;
+       __u64 lock_ibits;
+       bool cos_incompat = false, discard = false;
+       int no_name = 0;
+       int rc;
+
        ENTRY;
 
        DEBUG_REQ(D_INODE, req, "unlink "DFID"/"DNAME"", PFID(rr->rr_fid1),
@@ -800,34 +859,32 @@ static int mdt_reint_unlink(struct mdt_thread_info *info,
        if (info->mti_dlm_req)
                ldlm_request_cancel(req, info->mti_dlm_req, 0, LATF_SKIP);
 
-        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_UNLINK))
-                RETURN(err_serious(-ENOENT));
+       if (OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_UNLINK))
+               RETURN(err_serious(-ENOENT));
 
        if (!fid_is_md_operative(rr->rr_fid1))
                RETURN(-EPERM);
 
-        /*
-        * step 1: Found the parent.
-         */
        mp = mdt_object_find(info->mti_env, info->mti_mdt, rr->rr_fid1);
-       if (IS_ERR(mp)) {
-               rc = PTR_ERR(mp);
-               GOTO(out, rc);
+       if (IS_ERR(mp))
+               RETURN(PTR_ERR(mp));
+
+       if (mdt_object_remote(mp)) {
+               cos_incompat = true;
+       } else {
+               rc = mdt_version_get_check_save(info, mp, 0);
+               if (rc)
+                       GOTO(put_parent, rc);
        }
 
+relock:
        parent_lh = &info->mti_lh[MDT_LH_PARENT];
        mdt_lock_pdo_init(parent_lh, LCK_PW, &rr->rr_name);
-       rc = mdt_object_lock(info, mp, parent_lh, MDS_INODELOCK_UPDATE);
+       rc = mdt_reint_object_lock(info, mp, parent_lh, MDS_INODELOCK_UPDATE,
+                                  cos_incompat);
        if (rc != 0)
                GOTO(put_parent, rc);
 
-       if (!mdt_object_remote(mp)) {
-               rc = mdt_version_get_check_save(info, mp, 0);
-               if (rc)
-                       GOTO(unlock_parent, rc);
-       }
-
-       /* step 2: find & lock the child */
        /* lookup child object along with version checking */
        fid_zero(child_fid);
        rc = mdt_lookup_version_check(info, mp, &rr->rr_name, child_fid, 1);
@@ -864,8 +921,21 @@ static int mdt_reint_unlink(struct mdt_thread_info *info,
        if (IS_ERR(mc))
                GOTO(unlock_parent, rc = PTR_ERR(mc));
 
-        child_lh = &info->mti_lh[MDT_LH_CHILD];
-        mdt_lock_reg_init(child_lh, LCK_EX);
+       if (!cos_incompat) {
+               rc = mdt_object_striped(info, mc);
+               if (rc < 0)
+                       GOTO(unlock_parent, rc = PTR_ERR(mc));
+
+               cos_incompat = rc;
+               if (cos_incompat) {
+                       mdt_object_put(info->mti_env, mc);
+                       mdt_object_unlock(info, mp, parent_lh, -EAGAIN);
+                       goto relock;
+               }
+       }
+
+       child_lh = &info->mti_lh[MDT_LH_CHILD];
+       mdt_lock_reg_init(child_lh, LCK_EX);
        if (info->mti_spec.sp_rm_entry) {
                struct lu_ucred *uc  = mdt_ucred(info);
 
@@ -928,9 +998,11 @@ static int mdt_reint_unlink(struct mdt_thread_info *info,
                lock_ibits &= ~MDS_INODELOCK_LOOKUP;
        }
 
-       rc = mdt_object_lock(info, mc, child_lh, lock_ibits);
+       rc = mdt_reint_striped_lock(info, mc, child_lh, lock_ibits, einfo,
+                                   cos_incompat);
        if (rc != 0)
                GOTO(put_child, rc);
+
        /*
         * Now we can only make sure we need MA_INODE, in mdd layer, will check
         * whether need MA_LOV and MA_COOKIE.
@@ -938,13 +1010,6 @@ static int mdt_reint_unlink(struct mdt_thread_info *info,
        ma->ma_need = MA_INODE;
        ma->ma_valid = 0;
 
-       s0_lh = &info->mti_lh[MDT_LH_LOCAL];
-       mdt_lock_reg_init(s0_lh, LCK_EX);
-       rc = mdt_lock_slaves(info, mc, LCK_EX, MDS_INODELOCK_UPDATE, s0_lh,
-                            &s0_obj, einfo);
-       if (rc != 0)
-               GOTO(unlock_child, rc);
-
        mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
                       OBD_FAIL_MDS_REINT_UNLINK_WRITE);
        /* save version when object is locked */
@@ -956,43 +1021,50 @@ static int mdt_reint_unlink(struct mdt_thread_info *info,
                        mdt_object_child(mc), &rr->rr_name, ma, no_name);
 
        mutex_unlock(&mc->mot_lov_mutex);
+       if (rc != 0)
+               GOTO(unlock_child, rc);
 
-       if (rc == 0 && !lu_object_is_dying(&mc->mot_header))
+       if (!lu_object_is_dying(&mc->mot_header)) {
                rc = mdt_attr_get_complex(info, mc, ma);
-       if (rc == 0)
-               mdt_handle_last_unlink(info, mc, ma);
+               if (rc)
+                       GOTO(out_stat, rc);
+       } else {
+               discard = true;
+       }
+       mdt_handle_last_unlink(info, mc, ma);
 
-        if (ma->ma_valid & MA_INODE) {
-                switch (ma->ma_attr.la_mode & S_IFMT) {
-                case S_IFDIR:
+out_stat:
+       if (ma->ma_valid & MA_INODE) {
+               switch (ma->ma_attr.la_mode & S_IFMT) {
+               case S_IFDIR:
                        mdt_counter_incr(req, LPROC_MDT_RMDIR);
-                        break;
-                case S_IFREG:
-                case S_IFLNK:
-                case S_IFCHR:
-                case S_IFBLK:
-                case S_IFIFO:
-                case S_IFSOCK:
+                       break;
+               case S_IFREG:
+               case S_IFLNK:
+               case S_IFCHR:
+               case S_IFBLK:
+               case S_IFIFO:
+               case S_IFSOCK:
                        mdt_counter_incr(req, LPROC_MDT_UNLINK);
-                        break;
-                default:
-                        LASSERTF(0, "bad file type %o unlinking\n",
-                                 ma->ma_attr.la_mode);
-                }
-        }
+                       break;
+               default:
+                       LASSERTF(0, "bad file type %o unlinking\n",
+                               ma->ma_attr.la_mode);
+               }
+       }
 
-        EXIT;
+       EXIT;
 
 unlock_child:
-       mdt_unlock_slaves(info, mc, MDS_INODELOCK_UPDATE, s0_lh, s0_obj, einfo);
-       mdt_object_unlock(info, mc, child_lh, rc);
+       mdt_reint_striped_unlock(info, mc, child_lh, einfo, rc);
 put_child:
+       if (discard)
+               mdt_dom_check_and_discard(info, mc);
        mdt_object_put(info->mti_env, mc);
 unlock_parent:
        mdt_object_unlock(info, mp, parent_lh, rc);
 put_parent:
        mdt_object_put(info->mti_env, mp);
-out:
         return rc;
 }
 
@@ -1001,109 +1073,117 @@ out:
  * name.
  */
 static int mdt_reint_link(struct mdt_thread_info *info,
-                          struct mdt_lock_handle *lhc)
+                         struct mdt_lock_handle *lhc)
 {
-        struct mdt_reint_record *rr = &info->mti_rr;
-        struct ptlrpc_request   *req = mdt_info_req(info);
-        struct md_attr          *ma = &info->mti_attr;
-        struct mdt_object       *ms;
-        struct mdt_object       *mp;
-        struct mdt_lock_handle  *lhs;
-        struct mdt_lock_handle  *lhp;
-        int rc;
-        ENTRY;
+       struct mdt_reint_record *rr = &info->mti_rr;
+       struct ptlrpc_request   *req = mdt_info_req(info);
+       struct md_attr          *ma = &info->mti_attr;
+       struct mdt_object       *ms;
+       struct mdt_object       *mp;
+       struct mdt_lock_handle  *lhs;
+       struct mdt_lock_handle  *lhp;
+       bool cos_incompat;
+       int rc;
+       ENTRY;
 
        DEBUG_REQ(D_INODE, req, "link "DFID" to "DFID"/"DNAME,
                  PFID(rr->rr_fid1), PFID(rr->rr_fid2), PNAME(&rr->rr_name));
 
-        if (OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_LINK))
-                RETURN(err_serious(-ENOENT));
+       if (OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_LINK))
+               RETURN(err_serious(-ENOENT));
 
        if (info->mti_dlm_req)
                ldlm_request_cancel(req, info->mti_dlm_req, 0, LATF_SKIP);
 
-        /* Invalid case so return error immediately instead of
-         * processing it */
-        if (lu_fid_eq(rr->rr_fid1, rr->rr_fid2))
-                RETURN(-EPERM);
+       /* Invalid case so return error immediately instead of
+        * processing it */
+       if (lu_fid_eq(rr->rr_fid1, rr->rr_fid2))
+               RETURN(-EPERM);
 
        if (!fid_is_md_operative(rr->rr_fid1) ||
            !fid_is_md_operative(rr->rr_fid2))
                RETURN(-EPERM);
 
-        /* step 1: find & lock the target parent dir */
-        lhp = &info->mti_lh[MDT_LH_PARENT];
-       mdt_lock_pdo_init(lhp, LCK_PW, &rr->rr_name);
-        mp = mdt_object_find_lock(info, rr->rr_fid2, lhp,
-                                  MDS_INODELOCK_UPDATE);
-        if (IS_ERR(mp))
-                RETURN(PTR_ERR(mp));
-
-        rc = mdt_version_get_check_save(info, mp, 0);
-        if (rc)
-                GOTO(out_unlock_parent, rc);
-
-       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME3, 5);
+       /* step 1: find target parent dir */
+       mp = mdt_object_find(info->mti_env, info->mti_mdt, rr->rr_fid2);
+       if (IS_ERR(mp))
+               RETURN(PTR_ERR(mp));
 
-        /* step 2: find & lock the source */
-        lhs = &info->mti_lh[MDT_LH_CHILD];
-        mdt_lock_reg_init(lhs, LCK_EX);
+       rc = mdt_version_get_check_save(info, mp, 0);
+       if (rc)
+               GOTO(put_parent, rc);
 
-        ms = mdt_object_find(info->mti_env, info->mti_mdt, rr->rr_fid1);
-        if (IS_ERR(ms))
-                GOTO(out_unlock_parent, rc = PTR_ERR(ms));
+       /* step 2: find source */
+       ms = mdt_object_find(info->mti_env, info->mti_mdt, rr->rr_fid1);
+       if (IS_ERR(ms))
+               GOTO(put_parent, rc = PTR_ERR(ms));
 
        if (!mdt_object_exists(ms)) {
-               mdt_object_put(info->mti_env, ms);
                CDEBUG(D_INFO, "%s: "DFID" does not exist.\n",
                       mdt_obd_name(info->mti_mdt), PFID(rr->rr_fid1));
-               GOTO(out_unlock_parent, rc = -ENOENT);
+               GOTO(put_source, rc = -ENOENT);
        }
 
-       rc = mdt_object_lock(info, ms, lhs, MDS_INODELOCK_UPDATE |
-                            MDS_INODELOCK_XATTR);
-        if (rc != 0) {
-                mdt_object_put(info->mti_env, ms);
-                GOTO(out_unlock_parent, rc);
-        }
+       cos_incompat = (mdt_object_remote(mp) || mdt_object_remote(ms));
 
-        /* step 3: link it */
-        mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
-                       OBD_FAIL_MDS_REINT_LINK_WRITE);
+       lhp = &info->mti_lh[MDT_LH_PARENT];
+       mdt_lock_pdo_init(lhp, LCK_PW, &rr->rr_name);
+       rc = mdt_reint_object_lock(info, mp, lhp, MDS_INODELOCK_UPDATE,
+                                  cos_incompat);
+       if (rc != 0)
+               GOTO(put_source, rc);
+
+       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME3, 5);
+
+       lhs = &info->mti_lh[MDT_LH_CHILD];
+       mdt_lock_reg_init(lhs, LCK_EX);
+       rc = mdt_reint_object_lock(info, ms, lhs,
+                                  MDS_INODELOCK_UPDATE | MDS_INODELOCK_XATTR,
+                                  cos_incompat);
+       if (rc != 0)
+               GOTO(unlock_parent, rc);
+
+       /* step 3: link it */
+       mdt_fail_write(info->mti_env, info->mti_mdt->mdt_bottom,
+                       OBD_FAIL_MDS_REINT_LINK_WRITE);
 
        tgt_vbr_obj_set(info->mti_env, mdt_obj2dt(ms));
-        rc = mdt_version_get_check_save(info, ms, 1);
-        if (rc)
-                GOTO(out_unlock_child, rc);
+       rc = mdt_version_get_check_save(info, ms, 1);
+       if (rc)
+               GOTO(unlock_source, rc);
 
-        /** check target version by name during replay */
+       /** check target version by name during replay */
        rc = mdt_lookup_version_check(info, mp, &rr->rr_name,
                                      &info->mti_tmp_fid1, 2);
-        if (rc != 0 && rc != -ENOENT)
-                GOTO(out_unlock_child, rc);
-        /* save version of file name for replay, it must be ENOENT here */
-        if (!req_is_replay(mdt_info_req(info))) {
+       if (rc != 0 && rc != -ENOENT)
+               GOTO(unlock_source, rc);
+       /* save version of file name for replay, it must be ENOENT here */
+       if (!req_is_replay(mdt_info_req(info))) {
                if (rc != -ENOENT) {
                        CDEBUG(D_INFO, "link target "DNAME" existed!\n",
                               PNAME(&rr->rr_name));
-                       GOTO(out_unlock_child, rc = -EEXIST);
+                       GOTO(unlock_source, rc = -EEXIST);
                }
-                info->mti_ver[2] = ENOENT_VERSION;
-                mdt_version_save(mdt_info_req(info), info->mti_ver[2], 2);
-        }
+               info->mti_ver[2] = ENOENT_VERSION;
+               mdt_version_save(mdt_info_req(info), info->mti_ver[2], 2);
+       }
 
        rc = mdo_link(info->mti_env, mdt_object_child(mp),
-             mdt_object_child(ms), &rr->rr_name, ma);
+                     mdt_object_child(ms), &rr->rr_name, ma);
 
-        if (rc == 0)
+       if (rc == 0)
                mdt_counter_incr(req, LPROC_MDT_LINK);
 
-        EXIT;
-out_unlock_child:
-        mdt_object_unlock_put(info, ms, lhs, rc);
-out_unlock_parent:
-        mdt_object_unlock_put(info, mp, lhp, rc);
-        return rc;
+       EXIT;
+unlock_source:
+       mdt_object_unlock(info, ms, lhs, rc);
+unlock_parent:
+       mdt_object_unlock(info, mp, lhp, rc);
+put_source:
+       mdt_object_put(info->mti_env, ms);
+put_parent:
+       mdt_object_put(info->mti_env, mp);
+       return rc;
 }
 /**
  * lock the part of the directory according to the hash of the name
@@ -1111,11 +1191,13 @@ out_unlock_parent:
  */
 static int mdt_pdir_hash_lock(struct mdt_thread_info *info,
                              struct mdt_lock_handle *lh,
-                             struct mdt_object *obj, __u64 ibits)
+                             struct mdt_object *obj, __u64 ibits,
+                             bool cos_incompat)
 {
        struct ldlm_res_id *res = &info->mti_res_id;
        struct ldlm_namespace *ns = info->mti_mdt->mdt_namespace;
        union ldlm_policy_data *policy = &info->mti_policy;
+       __u64 dlmflags = LDLM_FL_LOCAL_ONLY | LDLM_FL_ATOMIC_CB;
        int rc;
 
        /*
@@ -1126,14 +1208,16 @@ static int mdt_pdir_hash_lock(struct mdt_thread_info *info,
        fid_build_pdo_res_name(mdt_object_fid(obj), lh->mlh_pdo_hash, res);
        memset(policy, 0, sizeof(*policy));
        policy->l_inodebits.bits = ibits;
+       if (cos_incompat &&
+           (lh->mlh_reg_mode == LCK_PW || lh->mlh_reg_mode == LCK_EX))
+               dlmflags |= LDLM_FL_COS_INCOMPAT;
        /*
         * Use LDLM_FL_LOCAL_ONLY for this lock. We do not know yet if it is
         * going to be sent to client. If it is - mdt_intent_policy() path will
         * fix it up and turn FL_LOCAL flag off.
         */
        rc = mdt_fid_lock(ns, &lh->mlh_reg_lh, lh->mlh_reg_mode, policy,
-                         res, LDLM_FL_LOCAL_ONLY | LDLM_FL_ATOMIC_CB,
-                         &info->mti_exp->exp_handle.h_cookie);
+                         res, dlmflags, &info->mti_exp->exp_handle.h_cookie);
        return rc;
 }
 
@@ -1193,45 +1277,6 @@ static void mdt_rename_unlock(struct lustre_handle *lh)
        EXIT;
 }
 
-/*
- * This is is_subdir() variant, it is CMD if cmm forwards it to correct
- * target. Source should not be ancestor of target dir. May be other rename
- * checks can be moved here later.
- */
-static int mdt_is_subdir(struct mdt_thread_info *info,
-                        struct mdt_object *dir,
-                        const struct lu_fid *fid)
-{
-       struct lu_fid dir_fid = dir->mot_header.loh_fid;
-        int rc = 0;
-        ENTRY;
-
-       /* If the source and target are in the same directory, they can not
-        * be parent/child relationship, so subdir check is not needed */
-       if (lu_fid_eq(&dir_fid, fid))
-               return 0;
-
-       if (!mdt_object_exists(dir))
-               RETURN(-ENOENT);
-
-       rc = mdo_is_subdir(info->mti_env, mdt_object_child(dir),
-                          fid, &dir_fid);
-       if (rc < 0) {
-               CERROR("%s: failed subdir check in "DFID" for "DFID
-                      ": rc = %d\n", mdt_obd_name(info->mti_mdt),
-                      PFID(&dir_fid), PFID(fid), rc);
-               /* Return EINVAL only if a parent is the @fid */
-               if (rc == -EINVAL)
-                       rc = -EIO;
-       } else {
-               /* check the found fid */
-               if (lu_fid_eq(&dir_fid, fid))
-                       rc = -EINVAL;
-       }
-
-        RETURN(rc);
-}
-
 /* Update object linkEA */
 struct mdt_lock_list {
        struct mdt_object       *mll_obj;
@@ -1291,6 +1336,7 @@ again:
                struct mdt_lock_list *mll;
                struct lu_name name;
                struct lu_fid  fid;
+               __u64 ibits;
 
                linkea_entry_unpack(ldata.ld_lee, &ldata.ld_reclen,
                                    &name, &fid);
@@ -1335,13 +1381,15 @@ again:
                 * cannot be gotten because of conflicting locks, then drop all
                 * current locks, send an AST to the client, and start again. */
                mdt_lock_pdo_init(&mll->mll_lh, LCK_PW, &name);
-               rc = mdt_object_lock_try(info, mdt_pobj, &mll->mll_lh,
-                                        MDS_INODELOCK_UPDATE);
-               if (rc == 0) {
-                       mdt_unlock_list(info, lock_list, rc);
+               ibits = 0;
+               rc = mdt_object_lock_try(info, mdt_pobj, &mll->mll_lh, &ibits,
+                                        MDS_INODELOCK_UPDATE, true);
+               if (!(ibits & MDS_INODELOCK_UPDATE)) {
+                       mdt_unlock_list(info, lock_list, 0);
 
-                       CDEBUG(D_INFO, "%s: busy lock on "DFID".\n",
-                              mdt_obd_name(mdt), PFID(&fid));
+                       CDEBUG(D_INFO, "%s: busy lock on "DFID" %s retry %d\n",
+                              mdt_obd_name(mdt), PFID(&fid), name.ln_name,
+                              retry_count);
 
                        if (retry_count == 0) {
                                mdt_object_put(info->mti_env, mdt_pobj);
@@ -1349,6 +1397,7 @@ again:
                                GOTO(out, rc = -EBUSY);
                        }
 
+                       mdt_lock_pdo_init(&mll->mll_lh, LCK_PW, &name);
                        rc = mdt_object_lock(info, mdt_pobj, &mll->mll_lh,
                                             MDS_INODELOCK_UPDATE);
                        if (rc != 0) {
@@ -1417,7 +1466,7 @@ static int mdt_reint_migrate_internal(struct mdt_thread_info *info,
        /* 1: lock the source dir. */
        msrcdir = mdt_object_find(info->mti_env, info->mti_mdt, rr->rr_fid1);
        if (IS_ERR(msrcdir)) {
-               CERROR("%s: cannot find source dir "DFID" : rc = %d\n",
+               CDEBUG(D_OTHER, "%s: cannot find source dir "DFID" : rc = %d\n",
                        mdt_obd_name(info->mti_mdt), PFID(rr->rr_fid1),
                        (int)PTR_ERR(msrcdir));
                RETURN(PTR_ERR(msrcdir));
@@ -1425,8 +1474,8 @@ static int mdt_reint_migrate_internal(struct mdt_thread_info *info,
 
        lh_dirp = &info->mti_lh[MDT_LH_PARENT];
        mdt_lock_pdo_init(lh_dirp, LCK_PW, &rr->rr_name);
-       rc = mdt_object_lock(info, msrcdir, lh_dirp,
-                            MDS_INODELOCK_UPDATE);
+       rc = mdt_reint_object_lock(info, msrcdir, lh_dirp, MDS_INODELOCK_UPDATE,
+                                  true);
        if (rc)
                GOTO(out_put_parent, rc);
 
@@ -1448,19 +1497,29 @@ static int mdt_reint_migrate_internal(struct mdt_thread_info *info,
        if (!fid_is_md_operative(old_fid))
                GOTO(out_unlock_parent, rc = -EPERM);
 
+       if (lu_fid_eq(old_fid, &info->mti_mdt->mdt_md_root_fid))
+               GOTO(out_unlock_parent, rc = -EPERM);
+
        mold = mdt_object_find(info->mti_env, info->mti_mdt, old_fid);
        if (IS_ERR(mold))
                GOTO(out_unlock_parent, rc = PTR_ERR(mold));
 
+       if (!mdt_object_exists(mold)) {
+               LU_OBJECT_DEBUG(D_INODE, info->mti_env,
+                               &mold->mot_obj,
+                               "object does not exist");
+               GOTO(out_put_child, rc = -ENOENT);
+       }
+
        if (mdt_object_remote(mold)) {
-               CERROR("%s: source "DFID" is on the remote MDT\n",
+               CDEBUG(D_OTHER, "%s: source "DFID" is on the remote MDT\n",
                       mdt_obd_name(info->mti_mdt), PFID(old_fid));
                GOTO(out_put_child, rc = -EREMOTE);
        }
 
        if (S_ISREG(lu_object_attr(&mold->mot_obj)) &&
            !mdt_object_remote(msrcdir)) {
-               CERROR("%s: parent "DFID" is still on the same"
+               CDEBUG(D_OTHER, "%s: parent "DFID" is still on the same"
                       " MDT, which should be migrated first:"
                       " rc = %d\n", mdt_obd_name(info->mti_mdt),
                       PFID(mdt_object_fid(msrcdir)), -EPERM);
@@ -1508,7 +1567,7 @@ static int mdt_reint_migrate_internal(struct mdt_thread_info *info,
                lease_broken = ldlm_is_cancel(lease);
                unlock_res_and_lock(lease);
 
-               LDLM_DEBUG(lease, DFID " lease broken? %d\n",
+               LDLM_DEBUG(lease, DFID " lease broken? %d",
                           PFID(mdt_object_fid(mold)), lease_broken);
 
                /* Cancel server side lease. Client side counterpart should
@@ -1543,7 +1602,7 @@ out_lease:
                lock_ibits &= ~MDS_INODELOCK_LOOKUP;
        }
 
-       rc = mdt_object_lock(info, mold, lh_childp, lock_ibits);
+       rc = mdt_reint_object_lock(info, mold, lh_childp, lock_ibits, true);
        if (rc != 0)
                GOTO(out_unlock_child, rc);
 
@@ -1556,7 +1615,8 @@ out_lease:
 
        if ((ma->ma_valid & MA_HSM) && ma->ma_hsm.mh_flags != 0) {
                rc = -ENOSYS;
-               CERROR("%s: cannot migrate HSM archived file "DFID": rc = %d\n",
+               CDEBUG(D_OTHER,
+                      "%s: cannot migrate HSM archived file "DFID": rc = %d\n",
                       mdt_obd_name(info->mti_mdt), PFID(old_fid), rc);
                GOTO(out_unlock_child, rc);
        }
@@ -1575,7 +1635,7 @@ out_lease:
                lmv_le_to_cpu(ma->ma_lmv, ma->ma_lmv);
                lmm1 = &ma->ma_lmv->lmv_md_v1;
                if (!(lmm1->lmv_hash_type & LMV_HASH_FLAG_MIGRATION)) {
-                       CERROR("%s: can not migrate striped dir "DFID
+                       CDEBUG(D_OTHER, "%s: can not migrate striped dir "DFID
                               ": rc = %d\n", mdt_obd_name(info->mti_mdt),
                               PFID(mdt_object_fid(mold)), -EPERM);
                        GOTO(out_unlock_child, rc = -EPERM);
@@ -1590,7 +1650,8 @@ out_lease:
                        GOTO(out_unlock_child, rc = PTR_ERR(mnew));
 
                if (!mdt_object_remote(mnew)) {
-                       CERROR("%s: "DFID" being migrated is on this MDT:"
+                       CDEBUG(D_OTHER,
+                              "%s: "DFID" being migrated is on this MDT:"
                               " rc  = %d\n", mdt_obd_name(info->mti_mdt),
                               PFID(rr->rr_fid2), -EPERM);
                        GOTO(out_put_new, rc = -EPERM);
@@ -1613,7 +1674,7 @@ out_lease:
                if (IS_ERR(mnew))
                        GOTO(out_unlock_child, rc = PTR_ERR(mnew));
                if (!mdt_object_remote(mnew)) {
-                       CERROR("%s: Migration "DFID" is on this MDT:"
+                       CDEBUG(D_OTHER, "%s: Migration "DFID" is on this MDT:"
                               " rc = %d\n", mdt_obd_name(info->mti_mdt),
                               PFID(rr->rr_fid2), -EXDEV);
                        GOTO(out_put_new, rc = -EXDEV);
@@ -1641,7 +1702,10 @@ out_put_new:
 out_unlock_child:
        mdt_object_unlock(info, mold, lh_childp, rc);
 out_unlock_list:
-       mdt_unlock_list(info, &lock_list, rc);
+       /* we don't really modify linkea objects, so we can safely decref these
+        * locks, and this can avoid saving them as COS locks, which may prevent
+        * subsequent migrate. */
+       mdt_unlock_list(info, &lock_list, 1);
        if (lease != NULL) {
                ldlm_reprocess_all(lease->l_resource);
                LDLM_LOCK_PUT(lease);
@@ -1685,12 +1749,13 @@ out_put:
 static int mdt_object_lock_save(struct mdt_thread_info *info,
                                struct mdt_object *dir,
                                struct mdt_lock_handle *lh,
-                               int idx)
+                               int idx, bool cos_incompat)
 {
        int rc;
 
        /* we lock the target dir if it is local */
-       rc = mdt_object_lock(info, dir, lh, MDS_INODELOCK_UPDATE);
+       rc = mdt_reint_object_lock(info, dir, lh, MDS_INODELOCK_UPDATE,
+                                  cos_incompat);
        if (rc != 0)
                return rc;
 
@@ -1699,97 +1764,102 @@ static int mdt_object_lock_save(struct mdt_thread_info *info,
        return 0;
 }
 
-
-static int mdt_rename_parents_lock(struct mdt_thread_info *info,
-                                  struct mdt_object **srcp,
-                                  struct mdt_object **tgtp)
+/*
+ * determine lock order of sobj and tobj
+ *
+ * there are two situations we need to lock tobj before sobj:
+ * 1. sobj is child of tobj
+ * 2. sobj and tobj are stripes of a directory, and stripe index of sobj is
+ *    larger than that of tobj
+ *
+ * \retval     1 lock tobj before sobj
+ * \retval     0 lock sobj before tobj
+ * \retval     -ev negative errno upon error
+ */
+static int mdt_rename_determine_lock_order(struct mdt_thread_info *info,
+                                          struct mdt_object *sobj,
+                                          struct mdt_object *tobj)
 {
-       struct mdt_reint_record *rr = &info->mti_rr;
-       const struct lu_fid     *fid_src = rr->rr_fid1;
-       const struct lu_fid     *fid_tgt = rr->rr_fid2;
-       struct mdt_lock_handle  *lh_src = &info->mti_lh[MDT_LH_PARENT];
-       struct mdt_lock_handle  *lh_tgt = &info->mti_lh[MDT_LH_CHILD];
-       struct mdt_object       *src;
-       struct mdt_object       *tgt;
-       int                      reverse = 0;
-       int                      rc;
-       ENTRY;
+       struct md_attr *ma = &info->mti_attr;
+       struct lu_fid *spfid = &info->mti_tmp_fid1;
+       struct lu_fid *tpfid = &info->mti_tmp_fid2;
+       struct lmv_mds_md_v1 *lmv;
+       __u32 sindex;
+       __u32 tindex;
+       int rc;
 
-       /* find both parents. */
-       src = mdt_object_find_check(info, fid_src, 0);
-       if (IS_ERR(src))
-               RETURN(PTR_ERR(src));
+       /* sobj and tobj are the same */
+       if (sobj == tobj)
+               return 0;
 
-       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME3, 5);
+       if (fid_is_root(mdt_object_fid(sobj)))
+               return 0;
 
-       if (lu_fid_eq(fid_src, fid_tgt)) {
-               tgt = src;
-               mdt_object_get(info->mti_env, tgt);
-       } else {
-               /* Check if the @src is not a child of the @tgt, otherwise a
-                * reverse locking must take place. */
-               rc = mdt_is_subdir(info, src, fid_tgt);
-               if (rc == -EINVAL)
-                       reverse = 1;
-               else if (rc)
-                       GOTO(err_src_put, rc);
-
-               tgt = mdt_object_find_check(info, fid_tgt, 1);
-               if (IS_ERR(tgt))
-                       GOTO(err_src_put, rc = PTR_ERR(tgt));
-       }
+       if (fid_is_root(mdt_object_fid(tobj)))
+               return 1;
 
-       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME4, 5);
+       /* check whether sobj is child of tobj */
+       rc = mdo_is_subdir(info->mti_env, mdt_object_child(sobj),
+                          mdt_object_fid(tobj));
+       if (rc < 0)
+               return rc;
 
-       /* lock parents in the proper order. */
-       if (reverse) {
-               rc = mdt_object_lock_save(info, tgt, lh_tgt, 1);
-               if (rc)
-                       GOTO(err_tgt_put, rc);
+       if (rc == 1)
+               return 1;
 
-               OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME, 5);
+       /* check whether sobj and tobj are children of the same parent */
+       rc = mdt_attr_get_pfid(info, sobj, spfid);
+       if (rc)
+               return rc;
 
-               rc = mdt_object_lock_save(info, src, lh_src, 0);
-       } else {
-               rc = mdt_object_lock_save(info, src, lh_src, 0);
-               if (rc)
-                       GOTO(err_tgt_put, rc);
+       rc = mdt_attr_get_pfid(info, tobj, tpfid);
+       if (rc)
+               return rc;
 
-               OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME, 5);
+       if (!lu_fid_eq(spfid, tpfid))
+               return 0;
 
-               if (tgt != src)
-                       rc = mdt_object_lock_save(info, tgt, lh_tgt, 1);
-               else if (lh_src->mlh_pdo_hash != lh_tgt->mlh_pdo_hash) {
-                       rc = mdt_pdir_hash_lock(info, lh_tgt, tgt,
-                                               MDS_INODELOCK_UPDATE);
-                       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_PDO_LOCK2, 10);
-               }
-       }
+       /* check whether sobj and tobj are sibling stripes */
+       ma->ma_need = MA_LMV;
+       ma->ma_valid = 0;
+       ma->ma_lmv = (union lmv_mds_md *)info->mti_xattr_buf;
+       ma->ma_lmv_size = sizeof(info->mti_xattr_buf);
+       rc = mdt_stripe_get(info, sobj, ma, XATTR_NAME_LMV);
        if (rc)
-               GOTO(err_unlock, rc);
+               return rc;
 
-       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME4, 5);
+       if (!(ma->ma_valid & MA_LMV))
+               return 0;
 
-       *srcp = src;
-       *tgtp = tgt;
-       RETURN(0);
+       lmv = &ma->ma_lmv->lmv_md_v1;
+       if (!(le32_to_cpu(lmv->lmv_magic) & LMV_MAGIC_STRIPE))
+               return 0;
+       sindex = le32_to_cpu(lmv->lmv_master_mdt_index);
 
-err_unlock:
-       /* The order does not matter as the handle is checked inside,
-        * as well as not used handle. */
-       mdt_object_unlock(info, src, lh_src, rc);
-       mdt_object_unlock(info, tgt, lh_tgt, rc);
-err_tgt_put:
-       mdt_object_put(info->mti_env, tgt);
-err_src_put:
-       mdt_object_put(info->mti_env, src);
-       RETURN(rc);
+       ma->ma_valid = 0;
+       rc = mdt_stripe_get(info, tobj, ma, XATTR_NAME_LMV);
+       if (rc)
+               return rc;
+
+       if (!(ma->ma_valid & MA_LMV))
+               return -ENODATA;
+
+       lmv = &ma->ma_lmv->lmv_md_v1;
+       if (!(le32_to_cpu(lmv->lmv_magic) & LMV_MAGIC_STRIPE))
+               return -EINVAL;
+       tindex = le32_to_cpu(lmv->lmv_master_mdt_index);
+
+       /* check stripe index of sobj and tobj */
+       if (sindex == tindex)
+               return -EINVAL;
+
+       return sindex < tindex ? 0 : 1;
 }
 
 /*
- * VBR: rename versions in reply: 0 - src parent; 1 - tgt parent;
- * 2 - src child; 3 - tgt child.
- * Update on disk version of src child.
+ * VBR: rename versions in reply: 0 - srcdir parent; 1 - tgtdir parent;
+ * 2 - srcdir child; 3 - tgtdir child.
+ * Update on disk version of srcdir child.
  */
 /**
  * For DNE phase I, only these renames are allowed
@@ -1806,39 +1876,109 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
                                     struct mdt_lock_handle *lhc)
 {
        struct mdt_reint_record *rr = &info->mti_rr;
-       struct md_attr          *ma = &info->mti_attr;
-       struct ptlrpc_request   *req = mdt_info_req(info);
-       struct mdt_object       *msrcdir = NULL;
-       struct mdt_object       *mtgtdir = NULL;
-       struct mdt_object       *mold;
-       struct mdt_object       *mnew = NULL;
-       struct mdt_lock_handle  *lh_srcdirp;
-       struct mdt_lock_handle  *lh_tgtdirp;
-       struct mdt_lock_handle  *lh_oldp = NULL;
-       struct mdt_lock_handle  *lh_newp = NULL;
-       struct lu_fid           *old_fid = &info->mti_tmp_fid1;
-       struct lu_fid           *new_fid = &info->mti_tmp_fid2;
-       __u64                   lock_ibits;
-       int                      rc;
+       struct md_attr *ma = &info->mti_attr;
+       struct ptlrpc_request *req = mdt_info_req(info);
+       struct mdt_object *msrcdir = NULL;
+       struct mdt_object *mtgtdir = NULL;
+       struct mdt_object *mold;
+       struct mdt_object *mnew = NULL;
+       struct mdt_lock_handle *lh_srcdirp;
+       struct mdt_lock_handle *lh_tgtdirp;
+       struct mdt_lock_handle *lh_oldp = NULL;
+       struct mdt_lock_handle *lh_newp = NULL;
+       struct lu_fid *old_fid = &info->mti_tmp_fid1;
+       struct lu_fid *new_fid = &info->mti_tmp_fid2;
+       __u64 lock_ibits;
+       bool reverse = false;
+       bool cos_incompat, discard = false;
+       int rc;
        ENTRY;
 
        DEBUG_REQ(D_INODE, req, "rename "DFID"/"DNAME" to "DFID"/"DNAME,
                  PFID(rr->rr_fid1), PNAME(&rr->rr_name),
                  PFID(rr->rr_fid2), PNAME(&rr->rr_tgt_name));
 
+       /* find both parents. */
+       msrcdir = mdt_object_find_check(info, rr->rr_fid1, 0);
+       if (IS_ERR(msrcdir))
+               RETURN(PTR_ERR(msrcdir));
+
+       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME3, 5);
+
+       if (lu_fid_eq(rr->rr_fid1, rr->rr_fid2)) {
+               mtgtdir = msrcdir;
+               mdt_object_get(info->mti_env, mtgtdir);
+       } else {
+               mtgtdir = mdt_object_find_check(info, rr->rr_fid2, 1);
+               if (IS_ERR(mtgtdir))
+                       GOTO(out_put_srcdir, rc = PTR_ERR(mtgtdir));
+       }
+
+       rc = mdt_rename_determine_lock_order(info, msrcdir, mtgtdir);
+       if (rc < 0)
+               GOTO(out_put_tgtdir, rc);
+
+       reverse = rc;
+
+       /* source needs to be looked up after locking source parent, otherwise
+        * this rename may race with unlink source, and cause rename hang, see
+        * sanityn.sh 55b, so check parents first, if later we found source is
+        * remote, relock parents. */
+       cos_incompat = (mdt_object_remote(msrcdir) ||
+                       mdt_object_remote(mtgtdir));
+
+       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME4, 5);
+
+       /* lock parents in the proper order. */
        lh_srcdirp = &info->mti_lh[MDT_LH_PARENT];
-       mdt_lock_pdo_init(lh_srcdirp, LCK_PW, &rr->rr_name);
        lh_tgtdirp = &info->mti_lh[MDT_LH_CHILD];
+
+relock:
+       mdt_lock_pdo_init(lh_srcdirp, LCK_PW, &rr->rr_name);
        mdt_lock_pdo_init(lh_tgtdirp, LCK_PW, &rr->rr_tgt_name);
 
-       /* step 1&2: lock the source and target dirs. */
-       rc = mdt_rename_parents_lock(info, &msrcdir, &mtgtdir);
-       if (rc)
-               RETURN(rc);
+       if (reverse) {
+               rc = mdt_object_lock_save(info, mtgtdir, lh_tgtdirp, 1,
+                                         cos_incompat);
+               if (rc)
+                       GOTO(out_put_tgtdir, rc);
 
+               OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME, 5);
+
+               rc = mdt_object_lock_save(info, msrcdir, lh_srcdirp, 0,
+                                         cos_incompat);
+               if (rc != 0) {
+                       mdt_object_unlock(info, mtgtdir, lh_tgtdirp, rc);
+                       GOTO(out_put_tgtdir, rc);
+               }
+       } else {
+               rc = mdt_object_lock_save(info, msrcdir, lh_srcdirp, 0,
+                                         cos_incompat);
+               if (rc)
+                       GOTO(out_put_tgtdir, rc);
+
+               OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME, 5);
+
+               if (mtgtdir != msrcdir) {
+                       rc = mdt_object_lock_save(info, mtgtdir, lh_tgtdirp, 1,
+                                                 cos_incompat);
+               } else if (lh_srcdirp->mlh_pdo_hash !=
+                          lh_tgtdirp->mlh_pdo_hash) {
+                       rc = mdt_pdir_hash_lock(info, lh_tgtdirp, mtgtdir,
+                                               MDS_INODELOCK_UPDATE,
+                                               cos_incompat);
+                       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_PDO_LOCK2, 10);
+               }
+               if (rc != 0) {
+                       mdt_object_unlock(info, msrcdir, lh_srcdirp, rc);
+                       GOTO(out_put_tgtdir, rc);
+               }
+       }
+
+       OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME4, 5);
        OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_RENAME2, 5);
 
-       /* step 3: find & lock the old object. */
+       /* find mold object. */
        fid_zero(old_fid);
        rc = mdt_lookup_version_check(info, msrcdir, &rr->rr_name, old_fid, 2);
        if (rc != 0)
@@ -1854,19 +1994,40 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
        if (IS_ERR(mold))
                GOTO(out_unlock_parents, rc = PTR_ERR(mold));
 
+       if (!mdt_object_exists(mold)) {
+               LU_OBJECT_DEBUG(D_INODE, info->mti_env,
+                               &mold->mot_obj,
+                               "object does not exist");
+               GOTO(out_put_old, rc = -ENOENT);
+       }
+
        /* Check if @mtgtdir is subdir of @mold, before locking child
         * to avoid reverse locking. */
-       rc = mdt_is_subdir(info, mtgtdir, old_fid);
-       if (rc)
-               GOTO(out_put_old, rc);
+       if (mtgtdir != msrcdir) {
+               rc = mdo_is_subdir(info->mti_env, mdt_object_child(mtgtdir),
+                                  old_fid);
+               if (rc) {
+                       if (rc == 1)
+                               rc = -EINVAL;
+                       GOTO(out_put_old, rc);
+               }
+       }
 
        tgt_vbr_obj_set(info->mti_env, mdt_obj2dt(mold));
        /* save version after locking */
        mdt_version_get_save(info, mold, 2);
 
-       /* step 4: find & lock the new object. */
-       /* new target object may not exist now */
-       /* lookup with version checking */
+       if (!cos_incompat && mdt_object_remote(mold)) {
+               cos_incompat = true;
+               mdt_object_put(info->mti_env, mold);
+               mdt_object_unlock(info, mtgtdir, lh_tgtdirp, -EAGAIN);
+               mdt_object_unlock(info, msrcdir, lh_srcdirp, -EAGAIN);
+               goto relock;
+       }
+
+       /* find mnew object:
+        * mnew target object may not exist now
+        * lookup with version checking */
        fid_zero(new_fid);
        rc = mdt_lookup_version_check(info, mtgtdir, &rr->rr_tgt_name, new_fid,
                                      3);
@@ -1886,6 +2047,13 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
                if (IS_ERR(mnew))
                        GOTO(out_put_old, rc = PTR_ERR(mnew));
 
+               if (!mdt_object_exists(mnew)) {
+                       LU_OBJECT_DEBUG(D_INODE, info->mti_env,
+                                       &mnew->mot_obj,
+                                       "object does not exist");
+                       GOTO(out_put_new, rc = -ENOENT);
+               }
+
                if (mdt_object_remote(mnew)) {
                        struct mdt_body  *repbody;
 
@@ -1907,7 +2075,6 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
 
                lh_oldp = &info->mti_lh[MDT_LH_OLD];
                mdt_lock_reg_init(lh_oldp, LCK_EX);
-
                lock_ibits = MDS_INODELOCK_LOOKUP | MDS_INODELOCK_XATTR;
                if (mdt_object_remote(msrcdir)) {
                        /* Enqueue lookup lock from the parent MDT */
@@ -1923,15 +2090,22 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
                        lock_ibits &= ~MDS_INODELOCK_LOOKUP;
                }
 
-               rc = mdt_object_lock(info, mold, lh_oldp, lock_ibits);
+               rc = mdt_reint_object_lock(info, mold, lh_oldp, lock_ibits,
+                                          cos_incompat);
                if (rc != 0)
                        GOTO(out_unlock_old, rc);
 
                /* Check if @msrcdir is subdir of @mnew, before locking child
                 * to avoid reverse locking. */
-               rc = mdt_is_subdir(info, msrcdir, new_fid);
-               if (rc)
-                       GOTO(out_unlock_old, rc);
+               if (mtgtdir != msrcdir) {
+                       rc = mdo_is_subdir(info->mti_env,
+                                          mdt_object_child(msrcdir), new_fid);
+                       if (rc) {
+                               if (rc == 1)
+                                       rc = -EINVAL;
+                               GOTO(out_unlock_old, rc);
+                       }
+               }
 
                /* We used to acquire MDS_INODELOCK_FULL here but we
                 * can't do this now because a running HSM restore on
@@ -1940,9 +2114,10 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
 
                lh_newp = &info->mti_lh[MDT_LH_NEW];
                mdt_lock_reg_init(lh_newp, LCK_EX);
-               rc = mdt_object_lock(info, mnew, lh_newp,
-                                    MDS_INODELOCK_LOOKUP |
-                                    MDS_INODELOCK_UPDATE);
+               rc = mdt_reint_object_lock(info, mnew, lh_newp,
+                                          MDS_INODELOCK_LOOKUP |
+                                          MDS_INODELOCK_UPDATE,
+                                          cos_incompat);
                if (rc != 0)
                        GOTO(out_unlock_old, rc);
 
@@ -1953,7 +2128,6 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
        } else {
                lh_oldp = &info->mti_lh[MDT_LH_OLD];
                mdt_lock_reg_init(lh_oldp, LCK_EX);
-
                lock_ibits = MDS_INODELOCK_LOOKUP | MDS_INODELOCK_XATTR;
                if (mdt_object_remote(msrcdir)) {
                        /* Enqueue lookup lock from the parent MDT */
@@ -1964,14 +2138,15 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
                                                    MDS_INODELOCK_LOOKUP,
                                                    false);
                        if (rc != ELDLM_OK)
-                               GOTO(out_put_new, rc);
+                               GOTO(out_put_old, rc);
 
                        lock_ibits &= ~MDS_INODELOCK_LOOKUP;
                }
 
-               rc = mdt_object_lock(info, mold, lh_oldp, lock_ibits);
+               rc = mdt_reint_object_lock(info, mold, lh_oldp, lock_ibits,
+                                          cos_incompat);
                if (rc != 0)
-                       GOTO(out_put_old, rc);
+                       GOTO(out_unlock_old, rc);
 
                mdt_enoent_version_save(info, 3);
        }
@@ -1996,8 +2171,10 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
        /* handle last link of tgt object */
        if (rc == 0) {
                mdt_counter_incr(req, LPROC_MDT_RENAME);
-               if (mnew)
+               if (mnew) {
                        mdt_handle_last_unlink(info, mnew, ma);
+                       discard = true;
+               }
 
                mdt_rename_counter_tally(info, info->mti_mdt, req,
                                         msrcdir, mtgtdir);
@@ -2009,13 +2186,20 @@ static int mdt_reint_rename_internal(struct mdt_thread_info *info,
 out_unlock_old:
        mdt_object_unlock(info, mold, lh_oldp, rc);
 out_put_new:
-       if (mnew != NULL)
+       if (mnew != NULL) {
+               if (discard)
+                       mdt_dom_check_and_discard(info, mnew);
                mdt_object_put(info->mti_env, mnew);
+       }
 out_put_old:
        mdt_object_put(info->mti_env, mold);
 out_unlock_parents:
-       mdt_object_unlock_put(info, mtgtdir, lh_tgtdirp, rc);
-       mdt_object_unlock_put(info, msrcdir, lh_srcdirp, rc);
+       mdt_object_unlock(info, mtgtdir, lh_tgtdirp, rc);
+       mdt_object_unlock(info, msrcdir, lh_srcdirp, rc);
+out_put_tgtdir:
+       mdt_object_put(info->mti_env, mtgtdir);
+out_put_srcdir:
+       mdt_object_put(info->mti_env, msrcdir);
        return rc;
 }
 
@@ -2071,6 +2255,85 @@ static int mdt_reint_migrate(struct mdt_thread_info *info,
        return mdt_reint_rename_or_migrate(info, lhc, false);
 }
 
+static int mdt_reint_resync(struct mdt_thread_info *info,
+                           struct mdt_lock_handle *lhc)
+{
+       struct mdt_reint_record *rr = &info->mti_rr;
+       struct ptlrpc_request   *req = mdt_info_req(info);
+       struct md_attr          *ma = &info->mti_attr;
+       struct mdt_object       *mo;
+       struct ldlm_lock        *lease;
+       struct mdt_body         *repbody;
+       struct md_layout_change  layout = { 0 };
+       bool                     lease_broken;
+       int                      rc, rc2;
+       ENTRY;
+
+       DEBUG_REQ(D_INODE, req, DFID": FLR file resync\n", PFID(rr->rr_fid1));
+
+       if (info->mti_dlm_req)
+               ldlm_request_cancel(req, info->mti_dlm_req, 0, LATF_SKIP);
+
+       mo = mdt_object_find(info->mti_env, info->mti_mdt, rr->rr_fid1);
+       if (IS_ERR(mo))
+               GOTO(out, rc = PTR_ERR(mo));
+
+       if (!mdt_object_exists(mo))
+               GOTO(out_obj, rc = -ENOENT);
+
+       if (!S_ISREG(lu_object_attr(&mo->mot_obj)))
+               GOTO(out_obj, rc = -EINVAL);
+
+       if (mdt_object_remote(mo))
+               GOTO(out_obj, rc = -EREMOTE);
+
+       lease = ldlm_handle2lock(rr->rr_handle);
+       if (lease == NULL)
+               GOTO(out_obj, rc = -ESTALE);
+
+       /* It's really necessary to grab open_sem and check if the lease lock
+        * has been lost. There would exist a concurrent writer coming in and
+        * generating some dirty data in memory cache, the writeback would fail
+        * after the layout version is increased by MDS_REINT_RESYNC RPC. */
+       if (!down_write_trylock(&mo->mot_open_sem))
+               GOTO(out_put_lease, rc = -EBUSY);
+
+       lock_res_and_lock(lease);
+       lease_broken = ldlm_is_cancel(lease);
+       unlock_res_and_lock(lease);
+       if (lease_broken)
+               GOTO(out_unlock, rc = -EBUSY);
+
+       /* the file has yet opened by anyone else after we took the lease. */
+       layout.mlc_opc = MD_LAYOUT_RESYNC;
+       rc = mdt_layout_change(info, mo, &layout);
+       if (rc)
+               GOTO(out_unlock, rc);
+
+       ma->ma_need = MA_INODE;
+       ma->ma_valid = 0;
+       rc = mdt_attr_get_complex(info, mo, ma);
+       if (rc != 0)
+               GOTO(out_unlock, rc);
+
+       repbody = req_capsule_server_get(info->mti_pill, &RMF_MDT_BODY);
+       mdt_pack_attr2body(info, repbody, &ma->ma_attr, mdt_object_fid(mo));
+
+       EXIT;
+out_unlock:
+       up_write(&mo->mot_open_sem);
+out_put_lease:
+       LDLM_LOCK_PUT(lease);
+out_obj:
+       mdt_object_put(info->mti_env, mo);
+out:
+       mdt_client_compatibility(info);
+       rc2 = mdt_fix_reply(info);
+       if (rc == 0)
+               rc = rc2;
+       return rc;
+}
+
 struct mdt_reinter {
        int (*mr_handler)(struct mdt_thread_info *, struct mdt_lock_handle *);
        enum lprocfs_extra_opc mr_extra_opc;
@@ -2113,6 +2376,10 @@ static const struct mdt_reinter mdt_reinters[] = {
                .mr_handler = &mdt_reint_migrate,
                .mr_extra_opc = MDS_REINT_RENAME,
        },
+       [REINT_RESYNC] = {
+               .mr_handler = &mdt_reint_resync,
+               .mr_extra_opc = MDS_REINT_RESYNC,
+       },
 };
 
 int mdt_reint_rec(struct mdt_thread_info *info,