Whamcloud - gitweb
LU-1403 ucred: ucred cleanup
[fs/lustre-release.git] / lustre / obdecho / echo_client.c
index e6471c8..0a11a3d 100644 (file)
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
+/*
+ * GPL HEADER START
  *
- *  Copyright (c) 2001-2003 Cluster File Systems, Inc.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
- *   This file is part of Lustre, http://www.lustre.org.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
  *
- *   Lustre is free software; you can redistribute it and/or
- *   modify it under the terms of version 2 of the GNU General Public
- *   License as published by the Free Software Foundation.
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
  *
- *   Lustre is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *   GNU General Public License for more details.
+ * 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
  *
- *   You should have received a copy of the GNU General Public License
- *   along with Lustre; if not, write to the Free Software
- *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 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.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Whamcloud, Inc.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
  */
 
 #define DEBUG_SUBSYSTEM S_ECHO
 #ifdef __KERNEL__
-#include <linux/version.h>
-#include <linux/module.h>
-#include <linux/fs.h>
-#include <linux/completion.h>
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
-#include <linux/iobuf.h>
-#endif
-#include <asm/div64.h>
+#include <libcfs/libcfs.h>
 #else
 #include <liblustre.h>
-#include <sys/capability.h>
 #endif
 
-#include <linux/obd.h>
-#include <linux/obd_support.h>
-#include <linux/obd_class.h>
-#include <linux/obd_echo.h>
-#include <linux/lustre_debug.h>
-#include <linux/lprocfs_status.h>
+#include <obd.h>
+#include <obd_support.h>
+#include <obd_class.h>
+#include <lustre_debug.h>
+#include <lprocfs_status.h>
+#include <cl_object.h>
+#include <lustre_fid.h>
+#include <lustre_acl.h>
+#include <lustre_net.h>
+#include <obd_lov.h>
+
+#include "echo_internal.h"
+
+/** \defgroup echo_client Echo Client
+ * @{
+ */
+
+struct echo_device {
+        struct cl_device        ed_cl;
+        struct echo_client_obd *ed_ec;
 
-static obd_id last_object_id;
+        struct cl_site          ed_site_myself;
+        struct cl_site         *ed_site;
+        struct lu_device       *ed_next;
+        int                     ed_next_islov;
+        int                     ed_next_ismd;
+        struct lu_client_seq   *ed_cl_seq;
+};
+
+struct echo_object {
+        struct cl_object        eo_cl;
+        struct cl_object_header eo_hdr;
+
+        struct echo_device     *eo_dev;
+        cfs_list_t              eo_obj_chain;
+        struct lov_stripe_md   *eo_lsm;
+        cfs_atomic_t            eo_npages;
+        int                     eo_deleted;
+};
+
+struct echo_object_conf {
+        struct cl_object_conf  eoc_cl;
+        struct lov_stripe_md **eoc_md;
+};
+
+struct echo_page {
+        struct cl_page_slice   ep_cl;
+       struct mutex            ep_lock;
+        cfs_page_t            *ep_vmpage;
+};
+
+struct echo_lock {
+        struct cl_lock_slice   el_cl;
+        cfs_list_t             el_chain;
+        struct echo_object    *el_object;
+        __u64                  el_cookie;
+        cfs_atomic_t           el_refcount;
+};
+
+struct echo_io {
+        struct cl_io_slice     ei_cl;
+};
 
 #if 0
-static void
-echo_printk_object (char *msg, struct ec_object *eco)
+struct echo_req {
+        struct cl_req_slice er_cl;
+};
+#endif
+
+static int echo_client_setup(const struct lu_env *env,
+                             struct obd_device *obddev,
+                             struct lustre_cfg *lcfg);
+static int echo_client_cleanup(struct obd_device *obddev);
+
+
+/** \defgroup echo_helpers Helper functions
+ * @{
+ */
+static inline struct echo_device *cl2echo_dev(const struct cl_device *dev)
+{
+        return container_of0(dev, struct echo_device, ed_cl);
+}
+
+static inline struct cl_device *echo_dev2cl(struct echo_device *d)
+{
+        return &d->ed_cl;
+}
+
+static inline struct echo_device *obd2echo_dev(const struct obd_device *obd)
+{
+        return cl2echo_dev(lu2cl_dev(obd->obd_lu_dev));
+}
+
+static inline struct cl_object *echo_obj2cl(struct echo_object *eco)
+{
+        return &eco->eo_cl;
+}
+
+static inline struct echo_object *cl2echo_obj(const struct cl_object *o)
+{
+        return container_of(o, struct echo_object, eo_cl);
+}
+
+static inline struct echo_page *cl2echo_page(const struct cl_page_slice *s)
+{
+        return container_of(s, struct echo_page, ep_cl);
+}
+
+static inline struct echo_lock *cl2echo_lock(const struct cl_lock_slice *s)
+{
+        return container_of(s, struct echo_lock, el_cl);
+}
+
+static inline struct cl_lock *echo_lock2cl(const struct echo_lock *ecl)
+{
+        return ecl->el_cl.cls_lock;
+}
+
+static struct lu_context_key echo_thread_key;
+static inline struct echo_thread_info *echo_env_info(const struct lu_env *env)
+{
+        struct echo_thread_info *info;
+        info = lu_context_key_get(&env->le_ctx, &echo_thread_key);
+        LASSERT(info != NULL);
+        return info;
+}
+
+static inline
+struct echo_object_conf *cl2echo_conf(const struct cl_object_conf *c)
+{
+        return container_of(c, struct echo_object_conf, eoc_cl);
+}
+
+static inline void lsm2fid(struct lov_stripe_md *lsm, struct lu_fid *fid)
+{
+        fid_zero(fid);
+        fid->f_seq = FID_SEQ_ECHO;
+        /* truncated to 32 bits by assignment */
+        fid->f_oid = lsm->lsm_object_id;
+        fid->f_ver = lsm->lsm_object_id >> 32;
+}
+/** @} echo_helpers */
+
+static struct echo_object *cl_echo_object_find(struct echo_device *d,
+                                               struct lov_stripe_md **lsm);
+static int cl_echo_object_put(struct echo_object *eco);
+static int cl_echo_enqueue   (struct echo_object *eco, obd_off start,
+                              obd_off end, int mode, __u64 *cookie);
+static int cl_echo_cancel    (struct echo_device *d, __u64 cookie);
+static int cl_echo_object_brw(struct echo_object *eco, int rw, obd_off offset,
+                              cfs_page_t **pages, int npages, int async);
+
+static struct echo_thread_info *echo_env_info(const struct lu_env *env);
+
+struct echo_thread_info {
+        struct echo_object_conf eti_conf;
+        struct lustre_md        eti_md;
+
+        struct cl_2queue        eti_queue;
+        struct cl_io            eti_io;
+        struct cl_lock_descr    eti_descr;
+        struct lu_fid           eti_fid;
+       struct lu_fid           eti_fid2;
+        struct md_op_spec       eti_spec;
+        struct lov_mds_md_v3    eti_lmm;
+        struct lov_user_md_v3   eti_lum;
+        struct md_attr          eti_ma;
+        struct lu_name          eti_lname;
+       /* per-thread values, can be re-used */
+       void                    *eti_big_lmm;
+       int                     eti_big_lmmsize;
+        char                    eti_name[20];
+        struct lu_buf           eti_buf;
+        char                    eti_xattr_buf[LUSTRE_POSIX_ACL_MAX_SIZE];
+};
+
+/* No session used right now */
+struct echo_session_info {
+        unsigned long dummy;
+};
+
+static cfs_mem_cache_t *echo_page_kmem;
+static cfs_mem_cache_t *echo_lock_kmem;
+static cfs_mem_cache_t *echo_object_kmem;
+static cfs_mem_cache_t *echo_thread_kmem;
+static cfs_mem_cache_t *echo_session_kmem;
+//static cfs_mem_cache_t *echo_req_kmem;
+
+static struct lu_kmem_descr echo_caches[] = {
+        {
+                .ckd_cache = &echo_page_kmem,
+                .ckd_name  = "echo_page_kmem",
+                .ckd_size  = sizeof (struct echo_page)
+        },
+        {
+                .ckd_cache = &echo_lock_kmem,
+                .ckd_name  = "echo_lock_kmem",
+                .ckd_size  = sizeof (struct echo_lock)
+        },
+        {
+                .ckd_cache = &echo_object_kmem,
+                .ckd_name  = "echo_object_kmem",
+                .ckd_size  = sizeof (struct echo_object)
+        },
+        {
+                .ckd_cache = &echo_thread_kmem,
+                .ckd_name  = "echo_thread_kmem",
+                .ckd_size  = sizeof (struct echo_thread_info)
+        },
+        {
+                .ckd_cache = &echo_session_kmem,
+                .ckd_name  = "echo_session_kmem",
+                .ckd_size  = sizeof (struct echo_session_info)
+        },
+#if 0
+        {
+                .ckd_cache = &echo_req_kmem,
+                .ckd_name  = "echo_req_kmem",
+                .ckd_size  = sizeof (struct echo_req)
+        },
+#endif
+        {
+                .ckd_cache = NULL
+        }
+};
+
+/** \defgroup echo_page Page operations
+ *
+ * Echo page operations.
+ *
+ * @{
+ */
+static cfs_page_t *echo_page_vmpage(const struct lu_env *env,
+                                    const struct cl_page_slice *slice)
+{
+        return cl2echo_page(slice)->ep_vmpage;
+}
+
+static int echo_page_own(const struct lu_env *env,
+                         const struct cl_page_slice *slice,
+                         struct cl_io *io, int nonblock)
+{
+        struct echo_page *ep = cl2echo_page(slice);
+
+        if (!nonblock)
+               mutex_lock(&ep->ep_lock);
+       else if (!mutex_trylock(&ep->ep_lock))
+                return -EAGAIN;
+        return 0;
+}
+
+static void echo_page_disown(const struct lu_env *env,
+                             const struct cl_page_slice *slice,
+                             struct cl_io *io)
+{
+        struct echo_page *ep = cl2echo_page(slice);
+
+       LASSERT(mutex_is_locked(&ep->ep_lock));
+       mutex_unlock(&ep->ep_lock);
+}
+
+static void echo_page_discard(const struct lu_env *env,
+                              const struct cl_page_slice *slice,
+                              struct cl_io *unused)
+{
+        cl_page_delete(env, slice->cpl_page);
+}
+
+static int echo_page_is_vmlocked(const struct lu_env *env,
+                                 const struct cl_page_slice *slice)
+{
+       if (mutex_is_locked(&cl2echo_page(slice)->ep_lock))
+                return -EBUSY;
+        return -ENODATA;
+}
+
+static void echo_page_completion(const struct lu_env *env,
+                                 const struct cl_page_slice *slice,
+                                 int ioret)
+{
+        LASSERT(slice->cpl_page->cp_sync_io != NULL);
+}
+
+static void echo_page_fini(const struct lu_env *env,
+                           struct cl_page_slice *slice)
+{
+        struct echo_page *ep    = cl2echo_page(slice);
+        struct echo_object *eco = cl2echo_obj(slice->cpl_obj);
+        cfs_page_t *vmpage      = ep->ep_vmpage;
+        ENTRY;
+
+        cfs_atomic_dec(&eco->eo_npages);
+        page_cache_release(vmpage);
+        OBD_SLAB_FREE_PTR(ep, echo_page_kmem);
+        EXIT;
+}
+
+static int echo_page_prep(const struct lu_env *env,
+                          const struct cl_page_slice *slice,
+                          struct cl_io *unused)
+{
+        return 0;
+}
+
+static int echo_page_print(const struct lu_env *env,
+                           const struct cl_page_slice *slice,
+                           void *cookie, lu_printer_t printer)
+{
+        struct echo_page *ep = cl2echo_page(slice);
+
+        (*printer)(env, cookie, LUSTRE_ECHO_CLIENT_NAME"-page@%p %d vm@%p\n",
+                  ep, mutex_is_locked(&ep->ep_lock), ep->ep_vmpage);
+        return 0;
+}
+
+static const struct cl_page_operations echo_page_ops = {
+        .cpo_own           = echo_page_own,
+        .cpo_disown        = echo_page_disown,
+        .cpo_discard       = echo_page_discard,
+        .cpo_vmpage        = echo_page_vmpage,
+        .cpo_fini          = echo_page_fini,
+        .cpo_print         = echo_page_print,
+        .cpo_is_vmlocked   = echo_page_is_vmlocked,
+        .io = {
+                [CRT_READ] = {
+                        .cpo_prep        = echo_page_prep,
+                        .cpo_completion  = echo_page_completion,
+                },
+                [CRT_WRITE] = {
+                        .cpo_prep        = echo_page_prep,
+                        .cpo_completion  = echo_page_completion,
+                }
+        }
+};
+/** @} echo_page */
+
+/** \defgroup echo_lock Locking
+ *
+ * echo lock operations
+ *
+ * @{
+ */
+static void echo_lock_fini(const struct lu_env *env,
+                           struct cl_lock_slice *slice)
+{
+        struct echo_lock *ecl = cl2echo_lock(slice);
+
+        LASSERT(cfs_list_empty(&ecl->el_chain));
+        OBD_SLAB_FREE_PTR(ecl, echo_lock_kmem);
+}
+
+static void echo_lock_delete(const struct lu_env *env,
+                             const struct cl_lock_slice *slice)
+{
+        struct echo_lock *ecl      = cl2echo_lock(slice);
+
+        LASSERT(cfs_list_empty(&ecl->el_chain));
+}
+
+static int echo_lock_fits_into(const struct lu_env *env,
+                               const struct cl_lock_slice *slice,
+                               const struct cl_lock_descr *need,
+                               const struct cl_io *unused)
+{
+        return 1;
+}
+
+static struct cl_lock_operations echo_lock_ops = {
+        .clo_fini      = echo_lock_fini,
+        .clo_delete    = echo_lock_delete,
+        .clo_fits_into = echo_lock_fits_into
+};
+
+/** @} echo_lock */
+
+/** \defgroup echo_cl_ops cl_object operations
+ *
+ * operations for cl_object
+ *
+ * @{
+ */
+static struct cl_page *echo_page_init(const struct lu_env *env,
+                                      struct cl_object *obj,
+                                      struct cl_page *page, cfs_page_t *vmpage)
+{
+        struct echo_page *ep;
+        ENTRY;
+
+        OBD_SLAB_ALLOC_PTR_GFP(ep, echo_page_kmem, CFS_ALLOC_IO);
+        if (ep != NULL) {
+                struct echo_object *eco = cl2echo_obj(obj);
+                ep->ep_vmpage = vmpage;
+                page_cache_get(vmpage);
+               mutex_init(&ep->ep_lock);
+                cl_page_slice_add(page, &ep->ep_cl, obj, &echo_page_ops);
+                cfs_atomic_inc(&eco->eo_npages);
+        }
+        RETURN(ERR_PTR(ep ? 0 : -ENOMEM));
+}
+
+static int echo_io_init(const struct lu_env *env, struct cl_object *obj,
+                        struct cl_io *io)
+{
+        return 0;
+}
+
+static int echo_lock_init(const struct lu_env *env,
+                          struct cl_object *obj, struct cl_lock *lock,
+                          const struct cl_io *unused)
+{
+        struct echo_lock *el;
+        ENTRY;
+
+        OBD_SLAB_ALLOC_PTR_GFP(el, echo_lock_kmem, CFS_ALLOC_IO);
+        if (el != NULL) {
+                cl_lock_slice_add(lock, &el->el_cl, obj, &echo_lock_ops);
+                el->el_object = cl2echo_obj(obj);
+                CFS_INIT_LIST_HEAD(&el->el_chain);
+                cfs_atomic_set(&el->el_refcount, 0);
+        }
+        RETURN(el == NULL ? -ENOMEM : 0);
+}
+
+static int echo_conf_set(const struct lu_env *env, struct cl_object *obj,
+                         const struct cl_object_conf *conf)
+{
+        return 0;
+}
+
+static const struct cl_object_operations echo_cl_obj_ops = {
+        .coo_page_init = echo_page_init,
+        .coo_lock_init = echo_lock_init,
+        .coo_io_init   = echo_io_init,
+        .coo_conf_set  = echo_conf_set
+};
+/** @} echo_cl_ops */
+
+/** \defgroup echo_lu_ops lu_object operations
+ *
+ * operations for echo lu object.
+ *
+ * @{
+ */
+static int echo_object_init(const struct lu_env *env, struct lu_object *obj,
+                            const struct lu_object_conf *conf)
+{
+        struct echo_device *ed         = cl2echo_dev(lu2cl_dev(obj->lo_dev));
+        struct echo_client_obd *ec     = ed->ed_ec;
+        struct echo_object *eco        = cl2echo_obj(lu2cl(obj));
+        ENTRY;
+
+        if (ed->ed_next) {
+                struct lu_object  *below;
+                struct lu_device  *under;
+
+                under = ed->ed_next;
+                below = under->ld_ops->ldo_object_alloc(env, obj->lo_header,
+                                                        under);
+                if (below == NULL)
+                        RETURN(-ENOMEM);
+                lu_object_add(obj, below);
+        }
+
+        if (!ed->ed_next_ismd) {
+                const struct cl_object_conf *cconf = lu2cl_conf(conf);
+                struct echo_object_conf *econf = cl2echo_conf(cconf);
+
+                LASSERT(econf->eoc_md);
+                eco->eo_lsm = *econf->eoc_md;
+                /* clear the lsm pointer so that it won't get freed. */
+                *econf->eoc_md = NULL;
+        } else {
+                eco->eo_lsm = NULL;
+        }
+
+        eco->eo_dev = ed;
+        cfs_atomic_set(&eco->eo_npages, 0);
+
+       spin_lock(&ec->ec_lock);
+       cfs_list_add_tail(&eco->eo_obj_chain, &ec->ec_objects);
+       spin_unlock(&ec->ec_lock);
+
+       RETURN(0);
+}
+
+/* taken from osc_unpackmd() */
+static int echo_alloc_memmd(struct echo_device *ed,
+                           struct lov_stripe_md **lsmp)
+{
+       int lsm_size;
+
+       ENTRY;
+
+       /* If export is lov/osc then use their obd method */
+       if (ed->ed_next != NULL)
+               return obd_alloc_memmd(ed->ed_ec->ec_exp, lsmp);
+       /* OFD has no unpackmd method, do everything here */
+       lsm_size = lov_stripe_md_size(1);
+
+       LASSERT(*lsmp == NULL);
+       OBD_ALLOC(*lsmp, lsm_size);
+       if (*lsmp == NULL)
+               RETURN(-ENOMEM);
+
+       OBD_ALLOC((*lsmp)->lsm_oinfo[0], sizeof(struct lov_oinfo));
+       if ((*lsmp)->lsm_oinfo[0] == NULL) {
+               OBD_FREE(*lsmp, lsm_size);
+               RETURN(-ENOMEM);
+       }
+
+       loi_init((*lsmp)->lsm_oinfo[0]);
+       (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES;
+
+       RETURN(lsm_size);
+}
+
+static int echo_free_memmd(struct echo_device *ed, struct lov_stripe_md **lsmp)
+{
+       int lsm_size;
+
+       ENTRY;
+
+       /* If export is lov/osc then use their obd method */
+       if (ed->ed_next != NULL)
+               return obd_free_memmd(ed->ed_ec->ec_exp, lsmp);
+       /* OFD has no unpackmd method, do everything here */
+       lsm_size = lov_stripe_md_size(1);
+
+       LASSERT(*lsmp != NULL);
+       OBD_FREE((*lsmp)->lsm_oinfo[0], sizeof(struct lov_oinfo));
+       OBD_FREE(*lsmp, lsm_size);
+       *lsmp = NULL;
+       RETURN(0);
+}
+
+static void echo_object_free(const struct lu_env *env, struct lu_object *obj)
+{
+        struct echo_object *eco    = cl2echo_obj(lu2cl(obj));
+        struct echo_client_obd *ec = eco->eo_dev->ed_ec;
+        ENTRY;
+
+        LASSERT(cfs_atomic_read(&eco->eo_npages) == 0);
+
+       spin_lock(&ec->ec_lock);
+        cfs_list_del_init(&eco->eo_obj_chain);
+       spin_unlock(&ec->ec_lock);
+
+        lu_object_fini(obj);
+        lu_object_header_fini(obj->lo_header);
+
+       if (eco->eo_lsm)
+               echo_free_memmd(eco->eo_dev, &eco->eo_lsm);
+       OBD_SLAB_FREE_PTR(eco, echo_object_kmem);
+       EXIT;
+}
+
+static int echo_object_print(const struct lu_env *env, void *cookie,
+                            lu_printer_t p, const struct lu_object *o)
+{
+        struct echo_object *obj = cl2echo_obj(lu2cl(o));
+
+        return (*p)(env, cookie, "echoclient-object@%p", obj);
+}
+
+static const struct lu_object_operations echo_lu_obj_ops = {
+        .loo_object_init      = echo_object_init,
+        .loo_object_delete    = NULL,
+        .loo_object_release   = NULL,
+        .loo_object_free      = echo_object_free,
+        .loo_object_print     = echo_object_print,
+        .loo_object_invariant = NULL
+};
+/** @} echo_lu_ops */
+
+/** \defgroup echo_lu_dev_ops  lu_device operations
+ *
+ * Operations for echo lu device.
+ *
+ * @{
+ */
+static struct lu_object *echo_object_alloc(const struct lu_env *env,
+                                           const struct lu_object_header *hdr,
+                                           struct lu_device *dev)
+{
+        struct echo_object *eco;
+        struct lu_object *obj = NULL;
+        ENTRY;
+
+        /* we're the top dev. */
+        LASSERT(hdr == NULL);
+        OBD_SLAB_ALLOC_PTR_GFP(eco, echo_object_kmem, CFS_ALLOC_IO);
+        if (eco != NULL) {
+                struct cl_object_header *hdr = &eco->eo_hdr;
+
+                obj = &echo_obj2cl(eco)->co_lu;
+                cl_object_header_init(hdr);
+                lu_object_init(obj, &hdr->coh_lu, dev);
+                lu_object_add_top(&hdr->coh_lu, obj);
+
+                eco->eo_cl.co_ops = &echo_cl_obj_ops;
+                obj->lo_ops       = &echo_lu_obj_ops;
+        }
+        RETURN(obj);
+}
+
+static struct lu_device_operations echo_device_lu_ops = {
+        .ldo_object_alloc   = echo_object_alloc,
+};
+
+/** @} echo_lu_dev_ops */
+
+static struct cl_device_operations echo_device_cl_ops = {
+};
+
+/** \defgroup echo_init Setup and teardown
+ *
+ * Init and fini functions for echo client.
+ *
+ * @{
+ */
+static int echo_site_init(const struct lu_env *env, struct echo_device *ed)
+{
+        struct cl_site *site = &ed->ed_site_myself;
+        int rc;
+
+        /* initialize site */
+        rc = cl_site_init(site, &ed->ed_cl);
+        if (rc) {
+                CERROR("Cannot initilize site for echo client(%d)\n", rc);
+                return rc;
+        }
+
+        rc = lu_site_init_finish(&site->cs_lu);
+        if (rc)
+                return rc;
+
+        ed->ed_site = site;
+        return 0;
+}
+
+static void echo_site_fini(const struct lu_env *env, struct echo_device *ed)
+{
+        if (ed->ed_site) {
+                if (!ed->ed_next_ismd)
+                        cl_site_fini(ed->ed_site);
+                ed->ed_site = NULL;
+        }
+}
+
+static void *echo_thread_key_init(const struct lu_context *ctx,
+                          struct lu_context_key *key)
+{
+        struct echo_thread_info *info;
+
+        OBD_SLAB_ALLOC_PTR_GFP(info, echo_thread_kmem, CFS_ALLOC_IO);
+        if (info == NULL)
+                info = ERR_PTR(-ENOMEM);
+        return info;
+}
+
+static void echo_thread_key_fini(const struct lu_context *ctx,
+                         struct lu_context_key *key, void *data)
+{
+        struct echo_thread_info *info = data;
+        OBD_SLAB_FREE_PTR(info, echo_thread_kmem);
+}
+
+static void echo_thread_key_exit(const struct lu_context *ctx,
+                         struct lu_context_key *key, void *data)
+{
+}
+
+static struct lu_context_key echo_thread_key = {
+        .lct_tags = LCT_CL_THREAD,
+        .lct_init = echo_thread_key_init,
+        .lct_fini = echo_thread_key_fini,
+        .lct_exit = echo_thread_key_exit
+};
+
+static void *echo_session_key_init(const struct lu_context *ctx,
+                                  struct lu_context_key *key)
 {
-        struct lov_stripe_md *lsm = eco->eco_lsm;
-        int                   i;
+        struct echo_session_info *session;
 
-        printk (KERN_INFO "Lustre: %s: object %p: "LPX64", refs %d%s: "LPX64
-                "=%u!%u\n", msg, eco, eco->eco_id, eco->eco_refcount,
-                eco->eco_deleted ? "(deleted) " : "",
-                lsm->lsm_object_id, lsm->lsm_stripe_size,
-                lsm->lsm_stripe_count);
+        OBD_SLAB_ALLOC_PTR_GFP(session, echo_session_kmem, CFS_ALLOC_IO);
+        if (session == NULL)
+                session = ERR_PTR(-ENOMEM);
+        return session;
+}
+
+static void echo_session_key_fini(const struct lu_context *ctx,
+                                 struct lu_context_key *key, void *data)
+{
+        struct echo_session_info *session = data;
+        OBD_SLAB_FREE_PTR(session, echo_session_kmem);
+}
+
+static void echo_session_key_exit(const struct lu_context *ctx,
+                                 struct lu_context_key *key, void *data)
+{
+}
+
+static struct lu_context_key echo_session_key = {
+        .lct_tags = LCT_SESSION,
+        .lct_init = echo_session_key_init,
+        .lct_fini = echo_session_key_fini,
+        .lct_exit = echo_session_key_exit
+};
+
+LU_TYPE_INIT_FINI(echo, &echo_thread_key, &echo_session_key);
+
+#define ECHO_SEQ_WIDTH 0xffffffff
+static int echo_fid_init(struct echo_device *ed, char *obd_name,
+                         struct md_site *ms)
+{
+        char *prefix;
+        int rc;
+        ENTRY;
+
+        OBD_ALLOC_PTR(ed->ed_cl_seq);
+        if (ed->ed_cl_seq == NULL)
+                RETURN(-ENOMEM);
+
+        OBD_ALLOC(prefix, MAX_OBD_NAME + 5);
+        if (prefix == NULL)
+                GOTO(out_free_seq, rc = -ENOMEM);
+
+        snprintf(prefix, MAX_OBD_NAME + 5, "srv-%s", obd_name);
+
+        /* Init client side sequence-manager */
+        rc = seq_client_init(ed->ed_cl_seq, NULL,
+                             LUSTRE_SEQ_METADATA,
+                             prefix, ms->ms_server_seq);
+        ed->ed_cl_seq->lcs_width = ECHO_SEQ_WIDTH;
+        OBD_FREE(prefix, MAX_OBD_NAME + 5);
+        if (rc)
+                GOTO(out_free_seq, rc);
+
+        RETURN(0);
+
+out_free_seq:
+        OBD_FREE_PTR(ed->ed_cl_seq);
+        ed->ed_cl_seq = NULL;
+        RETURN(rc);
+}
+
+static int echo_fid_fini(struct obd_device *obddev)
+{
+        struct echo_device *ed = obd2echo_dev(obddev);
+        ENTRY;
+
+        if (ed->ed_cl_seq != NULL) {
+                seq_client_fini(ed->ed_cl_seq);
+                OBD_FREE_PTR(ed->ed_cl_seq);
+                ed->ed_cl_seq = NULL;
+        }
+
+        RETURN(0);
+}
+
+static struct lu_device *echo_device_alloc(const struct lu_env *env,
+                                           struct lu_device_type *t,
+                                           struct lustre_cfg *cfg)
+{
+        struct lu_device   *next;
+        struct echo_device *ed;
+        struct cl_device   *cd;
+        struct obd_device  *obd = NULL; /* to keep compiler happy */
+        struct obd_device  *tgt;
+        const char *tgt_type_name;
+        int rc;
+        int cleanup = 0;
+        ENTRY;
+
+        OBD_ALLOC_PTR(ed);
+        if (ed == NULL)
+                GOTO(out, rc = -ENOMEM);
+
+        cleanup = 1;
+        cd = &ed->ed_cl;
+        rc = cl_device_init(cd, t);
+        if (rc)
+                GOTO(out, rc);
+
+        cd->cd_lu_dev.ld_ops = &echo_device_lu_ops;
+        cd->cd_ops = &echo_device_cl_ops;
+
+        cleanup = 2;
+        obd = class_name2obd(lustre_cfg_string(cfg, 0));
+        LASSERT(obd != NULL);
+        LASSERT(env != NULL);
+
+        tgt = class_name2obd(lustre_cfg_string(cfg, 1));
+        if (tgt == NULL) {
+                CERROR("Can not find tgt device %s\n",
+                        lustre_cfg_string(cfg, 1));
+                GOTO(out, rc = -ENODEV);
+        }
+
+        next = tgt->obd_lu_dev;
+        if (!strcmp(tgt->obd_type->typ_name, LUSTRE_MDT_NAME)) {
+                ed->ed_next_ismd = 1;
+        } else {
+                ed->ed_next_ismd = 0;
+                rc = echo_site_init(env, ed);
+                if (rc)
+                        GOTO(out, rc);
+        }
+        cleanup = 3;
+
+        rc = echo_client_setup(env, obd, cfg);
+        if (rc)
+                GOTO(out, rc);
+
+        ed->ed_ec = &obd->u.echo_client;
+        cleanup = 4;
+
+        if (ed->ed_next_ismd) {
+                /* Suppose to connect to some Metadata layer */
+                struct lu_site *ls;
+                struct lu_device *ld;
+                int    found = 0;
+
+                if (next == NULL) {
+                        CERROR("%s is not lu device type!\n",
+                               lustre_cfg_string(cfg, 1));
+                        GOTO(out, rc = -EINVAL);
+                }
+
+                tgt_type_name = lustre_cfg_string(cfg, 2);
+                if (!tgt_type_name) {
+                        CERROR("%s no type name for echo %s setup\n",
+                                lustre_cfg_string(cfg, 1),
+                                tgt->obd_type->typ_name);
+                        GOTO(out, rc = -EINVAL);
+                }
+
+                ls = next->ld_site;
+
+               spin_lock(&ls->ls_ld_lock);
+               cfs_list_for_each_entry(ld, &ls->ls_ld_linkage, ld_linkage) {
+                       if (strcmp(ld->ld_type->ldt_name, tgt_type_name) == 0) {
+                               found = 1;
+                               break;
+                       }
+               }
+               spin_unlock(&ls->ls_ld_lock);
+
+                if (found == 0) {
+                        CERROR("%s is not lu device type!\n",
+                               lustre_cfg_string(cfg, 1));
+                        GOTO(out, rc = -EINVAL);
+                }
+
+                next = ld;
+                /* For MD echo client, it will use the site in MDS stack */
+                ed->ed_site_myself.cs_lu = *ls;
+                ed->ed_site = &ed->ed_site_myself;
+                ed->ed_cl.cd_lu_dev.ld_site = &ed->ed_site_myself.cs_lu;
+                rc = echo_fid_init(ed, obd->obd_name, lu_site2md(ls));
+                if (rc) {
+                        CERROR("echo fid init error %d\n", rc);
+                        GOTO(out, rc);
+                }
+        } else {
+                 /* if echo client is to be stacked upon ost device, the next is
+                  * NULL since ost is not a clio device so far */
+                if (next != NULL && !lu_device_is_cl(next))
+                        next = NULL;
+
+                tgt_type_name = tgt->obd_type->typ_name;
+                if (next != NULL) {
+                        LASSERT(next != NULL);
+                        if (next->ld_site != NULL)
+                                GOTO(out, rc = -EBUSY);
+
+                        next->ld_site = &ed->ed_site->cs_lu;
+                        rc = next->ld_type->ldt_ops->ldto_device_init(env, next,
+                                                     next->ld_type->ldt_name,
+                                                     NULL);
+                        if (rc)
+                                GOTO(out, rc);
+
+                        /* Tricky case, I have to determine the obd type since
+                         * CLIO uses the different parameters to initialize
+                         * objects for lov & osc. */
+                        if (strcmp(tgt_type_name, LUSTRE_LOV_NAME) == 0)
+                                ed->ed_next_islov = 1;
+                        else
+                                LASSERT(strcmp(tgt_type_name,
+                                               LUSTRE_OSC_NAME) == 0);
+                } else
+                        LASSERT(strcmp(tgt_type_name, LUSTRE_OST_NAME) == 0);
+        }
+
+        ed->ed_next = next;
+        RETURN(&cd->cd_lu_dev);
+out:
+        switch(cleanup) {
+        case 4: {
+                int rc2;
+                rc2 = echo_client_cleanup(obd);
+                if (rc2)
+                        CERROR("Cleanup obd device %s error(%d)\n",
+                               obd->obd_name, rc2);
+        }
+
+        case 3:
+                echo_site_fini(env, ed);
+        case 2:
+                cl_device_fini(&ed->ed_cl);
+        case 1:
+                OBD_FREE_PTR(ed);
+        case 0:
+        default:
+                break;
+        }
+        return(ERR_PTR(rc));
+}
+
+static int echo_device_init(const struct lu_env *env, struct lu_device *d,
+                          const char *name, struct lu_device *next)
+{
+        LBUG();
+        return 0;
+}
+
+static struct lu_device *echo_device_fini(const struct lu_env *env,
+                                          struct lu_device *d)
+{
+        struct echo_device *ed = cl2echo_dev(lu2cl_dev(d));
+        struct lu_device *next = ed->ed_next;
+
+        while (next && !ed->ed_next_ismd)
+                next = next->ld_type->ldt_ops->ldto_device_fini(env, next);
+        return NULL;
+}
+
+static void echo_lock_release(const struct lu_env *env,
+                              struct echo_lock *ecl,
+                              int still_used)
+{
+        struct cl_lock *clk = echo_lock2cl(ecl);
+
+        cl_lock_get(clk);
+        cl_unuse(env, clk);
+        cl_lock_release(env, clk, "ec enqueue", ecl->el_object);
+        if (!still_used) {
+                cl_lock_mutex_get(env, clk);
+                cl_lock_cancel(env, clk);
+                cl_lock_delete(env, clk);
+                cl_lock_mutex_put(env, clk);
+        }
+        cl_lock_put(env, clk);
+}
+
+static struct lu_device *echo_device_free(const struct lu_env *env,
+                                          struct lu_device *d)
+{
+        struct echo_device     *ed   = cl2echo_dev(lu2cl_dev(d));
+        struct echo_client_obd *ec   = ed->ed_ec;
+        struct echo_object     *eco;
+        struct lu_device       *next = ed->ed_next;
+
+        CDEBUG(D_INFO, "echo device:%p is going to be freed, next = %p\n",
+               ed, next);
+
+        lu_site_purge(env, &ed->ed_site->cs_lu, -1);
+
+        /* check if there are objects still alive.
+         * It shouldn't have any object because lu_site_purge would cleanup
+         * all of cached objects. Anyway, probably the echo device is being
+         * parallelly accessed.
+         */
+       spin_lock(&ec->ec_lock);
+       cfs_list_for_each_entry(eco, &ec->ec_objects, eo_obj_chain)
+               eco->eo_deleted = 1;
+       spin_unlock(&ec->ec_lock);
+
+       /* purge again */
+       lu_site_purge(env, &ed->ed_site->cs_lu, -1);
+
+       CDEBUG(D_INFO,
+              "Waiting for the reference of echo object to be dropped\n");
+
+       /* Wait for the last reference to be dropped. */
+       spin_lock(&ec->ec_lock);
+       while (!cfs_list_empty(&ec->ec_objects)) {
+               spin_unlock(&ec->ec_lock);
+               CERROR("echo_client still has objects at cleanup time, "
+                      "wait for 1 second\n");
+               cfs_schedule_timeout_and_set_state(CFS_TASK_UNINT,
+                                                  cfs_time_seconds(1));
+               lu_site_purge(env, &ed->ed_site->cs_lu, -1);
+               spin_lock(&ec->ec_lock);
+       }
+       spin_unlock(&ec->ec_lock);
+
+        LASSERT(cfs_list_empty(&ec->ec_locks));
+
+        CDEBUG(D_INFO, "No object exists, exiting...\n");
+
+        echo_client_cleanup(d->ld_obd);
+        echo_fid_fini(d->ld_obd);
+        while (next && !ed->ed_next_ismd)
+                next = next->ld_type->ldt_ops->ldto_device_free(env, next);
+
+        LASSERT(ed->ed_site == lu2cl_site(d->ld_site));
+        echo_site_fini(env, ed);
+        cl_device_fini(&ed->ed_cl);
+        OBD_FREE_PTR(ed);
+
+        return NULL;
+}
+
+static const struct lu_device_type_operations echo_device_type_ops = {
+        .ldto_init = echo_type_init,
+        .ldto_fini = echo_type_fini,
+
+        .ldto_start = echo_type_start,
+        .ldto_stop  = echo_type_stop,
+
+        .ldto_device_alloc = echo_device_alloc,
+        .ldto_device_free  = echo_device_free,
+        .ldto_device_init  = echo_device_init,
+        .ldto_device_fini  = echo_device_fini
+};
+
+static struct lu_device_type echo_device_type = {
+        .ldt_tags     = LU_DEVICE_CL,
+        .ldt_name     = LUSTRE_ECHO_CLIENT_NAME,
+        .ldt_ops      = &echo_device_type_ops,
+        .ldt_ctx_tags = LCT_CL_THREAD | LCT_MD_THREAD | LCT_DT_THREAD,
+};
+/** @} echo_init */
+
+/** \defgroup echo_exports Exported operations
+ *
+ * exporting functions to echo client
+ *
+ * @{
+ */
+
+/* Interfaces to echo client obd device */
+static struct echo_object *cl_echo_object_find(struct echo_device *d,
+                                               struct lov_stripe_md **lsmp)
+{
+        struct lu_env *env;
+        struct echo_thread_info *info;
+        struct echo_object_conf *conf;
+        struct lov_stripe_md    *lsm;
+        struct echo_object *eco;
+        struct cl_object   *obj;
+        struct lu_fid *fid;
+        int refcheck;
+        ENTRY;
+
+        LASSERT(lsmp);
+        lsm = *lsmp;
+        LASSERT(lsm);
+        LASSERT(lsm->lsm_object_id);
+
+        /* Never return an object if the obd is to be freed. */
+        if (echo_dev2cl(d)->cd_lu_dev.ld_obd->obd_stopping)
+                RETURN(ERR_PTR(-ENODEV));
+
+        env = cl_env_get(&refcheck);
+        if (IS_ERR(env))
+                RETURN((void *)env);
+
+        info = echo_env_info(env);
+        conf = &info->eti_conf;
+        if (d->ed_next) {
+                if (!d->ed_next_islov) {
+                        struct lov_oinfo *oinfo = lsm->lsm_oinfo[0];
+                        LASSERT(oinfo != NULL);
+                        oinfo->loi_id = lsm->lsm_object_id;
+                        oinfo->loi_seq = lsm->lsm_object_seq;
+                        conf->eoc_cl.u.coc_oinfo = oinfo;
+                } else {
+                        struct lustre_md *md;
+                        md = &info->eti_md;
+                        memset(md, 0, sizeof *md);
+                        md->lsm = lsm;
+                        conf->eoc_cl.u.coc_md = md;
+                }
+        }
+        conf->eoc_md = lsmp;
+
+        fid  = &info->eti_fid;
+        lsm2fid(lsm, fid);
+
+       /* In the function below, .hs_keycmp resolves to
+        * lu_obj_hop_keycmp() */
+       /* coverity[overrun-buffer-val] */
+        obj = cl_object_find(env, echo_dev2cl(d), fid, &conf->eoc_cl);
+        if (IS_ERR(obj))
+                GOTO(out, eco = (void*)obj);
+
+        eco = cl2echo_obj(obj);
+        if (eco->eo_deleted) {
+                cl_object_put(env, obj);
+                eco = ERR_PTR(-EAGAIN);
+        }
+
+out:
+        cl_env_put(env, &refcheck);
+        RETURN(eco);
+}
+
+static int cl_echo_object_put(struct echo_object *eco)
+{
+        struct lu_env *env;
+        struct cl_object *obj = echo_obj2cl(eco);
+        int refcheck;
+        ENTRY;
+
+        env = cl_env_get(&refcheck);
+        if (IS_ERR(env))
+                RETURN(PTR_ERR(env));
+
+        /* an external function to kill an object? */
+        if (eco->eo_deleted) {
+                struct lu_object_header *loh = obj->co_lu.lo_header;
+                LASSERT(&eco->eo_hdr == luh2coh(loh));
+               set_bit(LU_OBJECT_HEARD_BANSHEE, &loh->loh_flags);
+        }
+
+        cl_object_put(env, obj);
+        cl_env_put(env, &refcheck);
+        RETURN(0);
+}
+
+static int cl_echo_enqueue0(struct lu_env *env, struct echo_object *eco,
+                            obd_off start, obd_off end, int mode,
+                            __u64 *cookie , __u32 enqflags)
+{
+        struct cl_io *io;
+        struct cl_lock *lck;
+        struct cl_object *obj;
+        struct cl_lock_descr *descr;
+        struct echo_thread_info *info;
+        int rc = -ENOMEM;
+        ENTRY;
+
+        info = echo_env_info(env);
+        io = &info->eti_io;
+        descr = &info->eti_descr;
+        obj = echo_obj2cl(eco);
+
+        descr->cld_obj   = obj;
+        descr->cld_start = cl_index(obj, start);
+        descr->cld_end   = cl_index(obj, end);
+        descr->cld_mode  = mode == LCK_PW ? CLM_WRITE : CLM_READ;
+        descr->cld_enq_flags = enqflags;
+        io->ci_obj = obj;
+
+        lck = cl_lock_request(env, io, descr, "ec enqueue", eco);
+        if (lck) {
+                struct echo_client_obd *ec = eco->eo_dev->ed_ec;
+                struct echo_lock *el;
+
+                rc = cl_wait(env, lck);
+                if (rc == 0) {
+                        el = cl2echo_lock(cl_lock_at(lck, &echo_device_type));
+                       spin_lock(&ec->ec_lock);
+                       if (cfs_list_empty(&el->el_chain)) {
+                               cfs_list_add(&el->el_chain, &ec->ec_locks);
+                               el->el_cookie = ++ec->ec_unique;
+                       }
+                       cfs_atomic_inc(&el->el_refcount);
+                       *cookie = el->el_cookie;
+                       spin_unlock(&ec->ec_lock);
+               } else {
+                       cl_lock_release(env, lck, "ec enqueue", cfs_current());
+               }
+       }
+       RETURN(rc);
+}
+
+static int cl_echo_enqueue(struct echo_object *eco, obd_off start, obd_off end,
+                           int mode, __u64 *cookie)
+{
+        struct echo_thread_info *info;
+        struct lu_env *env;
+        struct cl_io *io;
+        int refcheck;
+        int result;
+        ENTRY;
+
+        env = cl_env_get(&refcheck);
+        if (IS_ERR(env))
+                RETURN(PTR_ERR(env));
+
+        info = echo_env_info(env);
+        io = &info->eti_io;
+
+       io->ci_ignore_layout = 1;
+        result = cl_io_init(env, io, CIT_MISC, echo_obj2cl(eco));
+        if (result < 0)
+                GOTO(out, result);
+        LASSERT(result == 0);
+
+        result = cl_echo_enqueue0(env, eco, start, end, mode, cookie, 0);
+        cl_io_fini(env, io);
+
+        EXIT;
+out:
+        cl_env_put(env, &refcheck);
+        return result;
+}
+
+static int cl_echo_cancel0(struct lu_env *env, struct echo_device *ed,
+                           __u64 cookie)
+{
+        struct echo_client_obd *ec = ed->ed_ec;
+        struct echo_lock       *ecl = NULL;
+        cfs_list_t             *el;
+        int found = 0, still_used = 0;
+        ENTRY;
+
+        LASSERT(ec != NULL);
+       spin_lock(&ec->ec_lock);
+        cfs_list_for_each (el, &ec->ec_locks) {
+                ecl = cfs_list_entry (el, struct echo_lock, el_chain);
+                CDEBUG(D_INFO, "ecl: %p, cookie: "LPX64"\n", ecl, ecl->el_cookie);
+                found = (ecl->el_cookie == cookie);
+                if (found) {
+                        if (cfs_atomic_dec_and_test(&ecl->el_refcount))
+                                cfs_list_del_init(&ecl->el_chain);
+                        else
+                                still_used = 1;
+                        break;
+                }
+        }
+       spin_unlock(&ec->ec_lock);
+
+        if (!found)
+                RETURN(-ENOENT);
+
+        echo_lock_release(env, ecl, still_used);
+        RETURN(0);
+}
+
+static int cl_echo_cancel(struct echo_device *ed, __u64 cookie)
+{
+        struct lu_env *env;
+        int refcheck;
+        int rc;
+        ENTRY;
+
+        env = cl_env_get(&refcheck);
+        if (IS_ERR(env))
+                RETURN(PTR_ERR(env));
+
+        rc = cl_echo_cancel0(env, ed, cookie);
+
+        cl_env_put(env, &refcheck);
+        RETURN(rc);
+}
+
+static int cl_echo_async_brw(const struct lu_env *env, struct cl_io *io,
+                             enum cl_req_type unused, struct cl_2queue *queue)
+{
+        struct cl_page *clp;
+        struct cl_page *temp;
+        int result = 0;
+        ENTRY;
+
+        cl_page_list_for_each_safe(clp, temp, &queue->c2_qin) {
+                int rc;
+                rc = cl_page_cache_add(env, io, clp, CRT_WRITE);
+                if (rc == 0)
+                        continue;
+                result = result ?: rc;
+        }
+        RETURN(result);
+}
+
+static int cl_echo_object_brw(struct echo_object *eco, int rw, obd_off offset,
+                              cfs_page_t **pages, int npages, int async)
+{
+        struct lu_env           *env;
+        struct echo_thread_info *info;
+        struct cl_object        *obj = echo_obj2cl(eco);
+        struct echo_device      *ed  = eco->eo_dev;
+        struct cl_2queue        *queue;
+        struct cl_io            *io;
+        struct cl_page          *clp;
+        struct lustre_handle    lh = { 0 };
+        int page_size = cl_page_size(obj);
+        int refcheck;
+        int rc;
+        int i;
+        ENTRY;
+
+        LASSERT((offset & ~CFS_PAGE_MASK) == 0);
+        LASSERT(ed->ed_next != NULL);
+        env = cl_env_get(&refcheck);
+        if (IS_ERR(env))
+                RETURN(PTR_ERR(env));
+
+        info    = echo_env_info(env);
+        io      = &info->eti_io;
+        queue   = &info->eti_queue;
+
+        cl_2queue_init(queue);
+
+       io->ci_ignore_layout = 1;
+        rc = cl_io_init(env, io, CIT_MISC, obj);
+        if (rc < 0)
+                GOTO(out, rc);
+        LASSERT(rc == 0);
+
+
+        rc = cl_echo_enqueue0(env, eco, offset,
+                              offset + npages * CFS_PAGE_SIZE - 1,
+                              rw == READ ? LCK_PR : LCK_PW, &lh.cookie,
+                              CEF_NEVER);
+        if (rc < 0)
+                GOTO(error_lock, rc);
+
+        for (i = 0; i < npages; i++) {
+                LASSERT(pages[i]);
+                clp = cl_page_find(env, obj, cl_index(obj, offset),
+                                   pages[i], CPT_TRANSIENT);
+                if (IS_ERR(clp)) {
+                        rc = PTR_ERR(clp);
+                        break;
+                }
+                LASSERT(clp->cp_type == CPT_TRANSIENT);
+
+                rc = cl_page_own(env, io, clp);
+                if (rc) {
+                        LASSERT(clp->cp_state == CPS_FREEING);
+                        cl_page_put(env, clp);
+                        break;
+                }
+
+                cl_2queue_add(queue, clp);
+
+                /* drop the reference count for cl_page_find, so that the page
+                 * will be freed in cl_2queue_fini. */
+                cl_page_put(env, clp);
+                cl_page_clip(env, clp, 0, page_size);
+
+                offset += page_size;
+        }
+
+        if (rc == 0) {
+                enum cl_req_type typ = rw == READ ? CRT_READ : CRT_WRITE;
+
+                async = async && (typ == CRT_WRITE);
+                if (async)
+                        rc = cl_echo_async_brw(env, io, typ, queue);
+                else
+                       rc = cl_io_submit_sync(env, io, typ, queue, 0);
+                CDEBUG(D_INFO, "echo_client %s write returns %d\n",
+                       async ? "async" : "sync", rc);
+        }
+
+        cl_echo_cancel0(env, ed, lh.cookie);
+        EXIT;
+error_lock:
+        cl_2queue_discard(env, io, queue);
+        cl_2queue_disown(env, io, queue);
+        cl_2queue_fini(env, queue);
+        cl_io_fini(env, io);
+out:
+        cl_env_put(env, &refcheck);
+        return rc;
+}
+/** @} echo_exports */
+
+
+static obd_id last_object_id;
+
+static int
+echo_copyout_lsm (struct lov_stripe_md *lsm, void *_ulsm, int ulsm_nob)
+{
+        struct lov_stripe_md *ulsm = _ulsm;
+        int nob, i;
+
+        nob = offsetof (struct lov_stripe_md, lsm_oinfo[lsm->lsm_stripe_count]);
+        if (nob > ulsm_nob)
+                return (-EINVAL);
+
+        if (cfs_copy_to_user (ulsm, lsm, sizeof(ulsm)))
+                return (-EFAULT);
+
+        for (i = 0; i < lsm->lsm_stripe_count; i++) {
+                if (cfs_copy_to_user (ulsm->lsm_oinfo[i], lsm->lsm_oinfo[i],
+                                      sizeof(lsm->lsm_oinfo[0])))
+                        return (-EFAULT);
+        }
+        return 0;
+}
+
+static int
+echo_copyin_lsm (struct echo_device *ed, struct lov_stripe_md *lsm,
+                 void *ulsm, int ulsm_nob)
+{
+        struct echo_client_obd *ec = ed->ed_ec;
+        int                     i;
+
+        if (ulsm_nob < sizeof (*lsm))
+                return (-EINVAL);
+
+        if (cfs_copy_from_user (lsm, ulsm, sizeof (*lsm)))
+                return (-EFAULT);
+
+        if (lsm->lsm_stripe_count > ec->ec_nstripes ||
+            lsm->lsm_magic != LOV_MAGIC ||
+            (lsm->lsm_stripe_size & (~CFS_PAGE_MASK)) != 0 ||
+            ((__u64)lsm->lsm_stripe_size * lsm->lsm_stripe_count > ~0UL))
+                return (-EINVAL);
+
+
+        for (i = 0; i < lsm->lsm_stripe_count; i++) {
+                if (cfs_copy_from_user(lsm->lsm_oinfo[i],
+                                       ((struct lov_stripe_md *)ulsm)-> \
+                                       lsm_oinfo[i],
+                                       sizeof(lsm->lsm_oinfo[0])))
+                        return (-EFAULT);
+        }
+        return (0);
+}
+
+static inline void echo_md_build_name(struct lu_name *lname, char *name,
+                                     __u64 id)
+{
+       sprintf(name, LPU64, id);
+       lname->ln_name = name;
+       lname->ln_namelen = strlen(name);
+}
+
+/* similar to mdt_attr_get_complex */
+static int echo_big_lmm_get(const struct lu_env *env, struct md_object *o,
+                           struct md_attr *ma)
+{
+       struct echo_thread_info *info = echo_env_info(env);
+       int                      rc;
+
+       ENTRY;
+
+       LASSERT(ma->ma_lmm_size > 0);
+
+       rc = mo_xattr_get(env, o, &LU_BUF_NULL, XATTR_NAME_LOV);
+       if (rc < 0)
+               RETURN(rc);
+
+       /* big_lmm may need to be grown */
+       if (info->eti_big_lmmsize < rc) {
+               int size = size_roundup_power2(rc);
+
+               if (info->eti_big_lmmsize > 0) {
+                       /* free old buffer */
+                       LASSERT(info->eti_big_lmm);
+                       OBD_FREE_LARGE(info->eti_big_lmm,
+                                      info->eti_big_lmmsize);
+                       info->eti_big_lmm = NULL;
+                       info->eti_big_lmmsize = 0;
+               }
+
+               OBD_ALLOC_LARGE(info->eti_big_lmm, size);
+               if (info->eti_big_lmm == NULL)
+                       RETURN(-ENOMEM);
+               info->eti_big_lmmsize = size;
+       }
+       LASSERT(info->eti_big_lmmsize >= rc);
+
+       info->eti_buf.lb_buf = info->eti_big_lmm;
+       info->eti_buf.lb_len = info->eti_big_lmmsize;
+       rc = mo_xattr_get(env, o, &info->eti_buf, XATTR_NAME_LOV);
+       if (rc < 0)
+               RETURN(rc);
+
+       ma->ma_valid |= MA_LOV;
+       ma->ma_lmm = info->eti_big_lmm;
+       ma->ma_lmm_size = rc;
+
+       RETURN(0);
+}
+
+int echo_attr_get_complex(const struct lu_env *env, struct md_object *next,
+                         struct md_attr *ma)
+{
+       struct echo_thread_info *info = echo_env_info(env);
+       struct lu_buf           *buf = &info->eti_buf;
+       cfs_umode_t              mode = lu_object_attr(&next->mo_lu);
+       int                      need = ma->ma_need;
+       int                      rc = 0, rc2;
+
+       ENTRY;
+
+       ma->ma_valid = 0;
+
+       if (need & MA_INODE) {
+               ma->ma_need = MA_INODE;
+               rc = mo_attr_get(env, next, ma);
+               if (rc)
+                       GOTO(out, rc);
+               ma->ma_valid |= MA_INODE;
+       }
+
+       if (need & MA_LOV) {
+               if (S_ISREG(mode) || S_ISDIR(mode)) {
+                       LASSERT(ma->ma_lmm_size > 0);
+                       buf->lb_buf = ma->ma_lmm;
+                       buf->lb_len = ma->ma_lmm_size;
+                       rc2 = mo_xattr_get(env, next, buf, XATTR_NAME_LOV);
+                       if (rc2 > 0) {
+                               ma->ma_lmm_size = rc2;
+                               ma->ma_valid |= MA_LOV;
+                       } else if (rc2 == -ENODATA) {
+                               /* no LOV EA */
+                               ma->ma_lmm_size = 0;
+                       } else if (rc2 == -ERANGE) {
+                               rc2 = echo_big_lmm_get(env, next, ma);
+                               if (rc2 < 0)
+                                       GOTO(out, rc = rc2);
+                       } else {
+                               GOTO(out, rc = rc2);
+                       }
+               }
+       }
+
+#ifdef CONFIG_FS_POSIX_ACL
+       if (need & MA_ACL_DEF && S_ISDIR(mode)) {
+               buf->lb_buf = ma->ma_acl;
+               buf->lb_len = ma->ma_acl_size;
+               rc2 = mo_xattr_get(env, next, buf, XATTR_NAME_ACL_DEFAULT);
+               if (rc2 > 0) {
+                       ma->ma_acl_size = rc2;
+                       ma->ma_valid |= MA_ACL_DEF;
+               } else if (rc2 == -ENODATA) {
+                       /* no ACLs */
+                       ma->ma_acl_size = 0;
+               } else {
+                       GOTO(out, rc = rc2);
+               }
+       }
+#endif
+out:
+       ma->ma_need = need;
+       CDEBUG(D_INODE, "after getattr rc = %d, ma_valid = "LPX64" ma_lmm=%p\n",
+              rc, ma->ma_valid, ma->ma_lmm);
+       RETURN(rc);
+}
+
+static int
+echo_md_create_internal(const struct lu_env *env, struct echo_device *ed,
+                       struct md_object *parent, struct lu_fid *fid,
+                       struct lu_name *lname, struct md_op_spec *spec,
+                       struct md_attr *ma)
+{
+       struct lu_object        *ec_child, *child;
+       struct lu_device        *ld = ed->ed_next;
+       struct echo_thread_info *info = echo_env_info(env);
+       struct lu_fid           *fid2 = &info->eti_fid2;
+       struct lu_object_conf    conf = { .loc_flags = LOC_F_NEW };
+       int                      rc;
+
+       ENTRY;
+
+       rc = mdo_lookup(env, parent, lname, fid2, spec);
+       if (rc == 0)
+               return -EEXIST;
+       else if (rc != -ENOENT)
+               return rc;
+
+       ec_child = lu_object_find_at(env, &ed->ed_cl.cd_lu_dev,
+                                    fid, &conf);
+        if (IS_ERR(ec_child)) {
+                CERROR("Can not find the child "DFID": rc = %ld\n", PFID(fid),
+                        PTR_ERR(ec_child));
+               RETURN(PTR_ERR(ec_child));
+        }
+
+        child = lu_object_locate(ec_child->lo_header, ld->ld_type);
+        if (child == NULL) {
+                CERROR("Can not locate the child "DFID"\n", PFID(fid));
+                GOTO(out_put, rc = -EINVAL);
+        }
+
+        CDEBUG(D_RPCTRACE, "Start creating object "DFID" %s %p\n",
+               PFID(lu_object_fid(&parent->mo_lu)), lname->ln_name, parent);
+
+       /*
+        * Do not perform lookup sanity check. We know that name does not exist.
+        */
+       spec->sp_cr_lookup = 0;
+        rc = mdo_create(env, parent, lname, lu2md(child), spec, ma);
+        if (rc) {
+                CERROR("Can not create child "DFID": rc = %d\n", PFID(fid), rc);
+                GOTO(out_put, rc);
+        }
+        CDEBUG(D_RPCTRACE, "End creating object "DFID" %s %p rc  = %d\n",
+               PFID(lu_object_fid(&parent->mo_lu)), lname->ln_name, parent, rc);
+       EXIT;
+out_put:
+        lu_object_put(env, ec_child);
+        return rc;
+}
+
+static int echo_set_lmm_size(const struct lu_env *env, struct lu_device *ld,
+                            struct md_attr *ma)
+{
+       struct echo_thread_info *info = echo_env_info(env);
+
+       if (strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME)) {
+               ma->ma_lmm = (void *)&info->eti_lmm;
+               ma->ma_lmm_size = sizeof(info->eti_lmm);
+       } else {
+               LASSERT(info->eti_big_lmmsize);
+               ma->ma_lmm = info->eti_big_lmm;
+               ma->ma_lmm_size = info->eti_big_lmmsize;
+       }
+
+       return 0;
+}
+
+static int echo_create_md_object(const struct lu_env *env,
+                                 struct echo_device *ed,
+                                 struct lu_object *ec_parent,
+                                 struct lu_fid *fid,
+                                 char *name, int namelen,
+                                 __u64 id, __u32 mode, int count,
+                                 int stripe_count, int stripe_offset)
+{
+        struct lu_object        *parent;
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_name          *lname = &info->eti_lname;
+        struct md_op_spec       *spec = &info->eti_spec;
+        struct md_attr          *ma = &info->eti_ma;
+        struct lu_device        *ld = ed->ed_next;
+        int                      rc = 0;
+        int                      i;
+
+       ENTRY;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+       if (parent == NULL)
+               RETURN(-ENXIO);
+
+        memset(ma, 0, sizeof(*ma));
+        memset(spec, 0, sizeof(*spec));
+        if (stripe_count != 0) {
+                spec->sp_cr_flags |= FMODE_WRITE;
+               echo_set_lmm_size(env, ld, ma);
+                if (stripe_count != -1) {
+                        struct lov_user_md_v3 *lum = &info->eti_lum;
+
+                        lum->lmm_magic = LOV_USER_MAGIC_V3;
+                        lum->lmm_stripe_count = stripe_count;
+                        lum->lmm_stripe_offset = stripe_offset;
+                        lum->lmm_pattern = 0;
+                        spec->u.sp_ea.eadata = lum;
+                       spec->u.sp_ea.eadatalen = sizeof(*lum);
+                        spec->sp_cr_flags |= MDS_OPEN_HAS_EA;
+                }
+        }
+
+        ma->ma_attr.la_mode = mode;
+       ma->ma_attr.la_valid = LA_CTIME | LA_MODE;
+        ma->ma_attr.la_ctime = cfs_time_current_64();
+
+        if (name != NULL) {
+                lname->ln_name = name;
+                lname->ln_namelen = namelen;
+                /* If name is specified, only create one object by name */
+                rc = echo_md_create_internal(env, ed, lu2md(parent), fid, lname,
+                                             spec, ma);
+               RETURN(rc);
+        }
+
+        /* Create multiple object sequenced by id */
+        for (i = 0; i < count; i++) {
+                char *tmp_name = info->eti_name;
+
+                echo_md_build_name(lname, tmp_name, id);
+
+                rc = echo_md_create_internal(env, ed, lu2md(parent), fid, lname,
+                                             spec, ma);
+                if (rc) {
+                        CERROR("Can not create child %s: rc = %d\n", tmp_name,
+                                rc);
+                        break;
+                }
+                id++;
+                fid->f_oid++;
+        }
+
+       RETURN(rc);
+}
+
+static struct lu_object *echo_md_lookup(const struct lu_env *env,
+                                        struct echo_device *ed,
+                                        struct md_object *parent,
+                                        struct lu_name *lname)
+{
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_fid           *fid = &info->eti_fid;
+        struct lu_object        *child;
+        int    rc;
+        ENTRY;
+
+        CDEBUG(D_INFO, "lookup %s in parent "DFID" %p\n", lname->ln_name,
+               PFID(fid), parent);
+        rc = mdo_lookup(env, parent, lname, fid, NULL);
+        if (rc) {
+                CERROR("lookup %s: rc = %d\n", lname->ln_name, rc);
+                RETURN(ERR_PTR(rc));
+        }
+
+        child = lu_object_find_at(env, &ed->ed_cl.cd_lu_dev, fid, NULL);
+
+        RETURN(child);
+}
+
+static int echo_setattr_object(const struct lu_env *env,
+                               struct echo_device *ed,
+                               struct lu_object *ec_parent,
+                               __u64 id, int count)
+{
+        struct lu_object        *parent;
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_name          *lname = &info->eti_lname;
+        char                    *name = info->eti_name;
+        struct lu_device        *ld = ed->ed_next;
+        struct lu_buf           *buf = &info->eti_buf;
+        int                      rc = 0;
+        int                      i;
+
+       ENTRY;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+       if (parent == NULL)
+               RETURN(-ENXIO);
+
+        for (i = 0; i < count; i++) {
+                struct lu_object *ec_child, *child;
+
+                echo_md_build_name(lname, name, id);
+
+                ec_child = echo_md_lookup(env, ed, lu2md(parent), lname);
+                if (IS_ERR(ec_child)) {
+                        CERROR("Can't find child %s: rc = %ld\n",
+                                lname->ln_name, PTR_ERR(ec_child));
+                        RETURN(PTR_ERR(ec_child));
+                }
+
+                child = lu_object_locate(ec_child->lo_header, ld->ld_type);
+                if (child == NULL) {
+                        CERROR("Can not locate the child %s\n", lname->ln_name);
+                        lu_object_put(env, ec_child);
+                        rc = -EINVAL;
+                        break;
+                }
+
+                CDEBUG(D_RPCTRACE, "Start setattr object "DFID"\n",
+                       PFID(lu_object_fid(child)));
+
+               buf->lb_buf = info->eti_xattr_buf;
+               buf->lb_len = sizeof(info->eti_xattr_buf);
+
+                sprintf(name, "%s.test1", XATTR_USER_PREFIX);
+                rc = mo_xattr_set(env, lu2md(child), buf, name,
+                                  LU_XATTR_CREATE);
+               if (rc < 0) {
+                        CERROR("Can not setattr child "DFID": rc = %d\n",
+                                PFID(lu_object_fid(child)), rc);
+                        lu_object_put(env, ec_child);
+                        break;
+                }
+                CDEBUG(D_RPCTRACE, "End setattr object "DFID"\n",
+                       PFID(lu_object_fid(child)));
+                id++;
+                lu_object_put(env, ec_child);
+        }
+       RETURN(rc);
+}
+
+static int echo_getattr_object(const struct lu_env *env,
+                               struct echo_device *ed,
+                               struct lu_object *ec_parent,
+                               __u64 id, int count)
+{
+        struct lu_object        *parent;
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_name          *lname = &info->eti_lname;
+        char                    *name = info->eti_name;
+        struct md_attr          *ma = &info->eti_ma;
+        struct lu_device        *ld = ed->ed_next;
+        int                      rc = 0;
+        int                      i;
+
+       ENTRY;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+       if (parent == NULL)
+               RETURN(-ENXIO);
+
+        memset(ma, 0, sizeof(*ma));
+        ma->ma_need |= MA_INODE | MA_LOV | MA_PFID | MA_HSM | MA_ACL_DEF;
+        ma->ma_acl = info->eti_xattr_buf;
+        ma->ma_acl_size = sizeof(info->eti_xattr_buf);
+
+        for (i = 0; i < count; i++) {
+                struct lu_object *ec_child, *child;
+
+                ma->ma_valid = 0;
+                echo_md_build_name(lname, name, id);
+               echo_set_lmm_size(env, ld, ma);
+
+                ec_child = echo_md_lookup(env, ed, lu2md(parent), lname);
+                if (IS_ERR(ec_child)) {
+                        CERROR("Can't find child %s: rc = %ld\n",
+                               lname->ln_name, PTR_ERR(ec_child));
+                        RETURN(PTR_ERR(ec_child));
+                }
+
+                child = lu_object_locate(ec_child->lo_header, ld->ld_type);
+                if (child == NULL) {
+                        CERROR("Can not locate the child %s\n", lname->ln_name);
+                        lu_object_put(env, ec_child);
+                       RETURN(-EINVAL);
+                }
+
+                CDEBUG(D_RPCTRACE, "Start getattr object "DFID"\n",
+                       PFID(lu_object_fid(child)));
+               rc = echo_attr_get_complex(env, lu2md(child), ma);
+                if (rc) {
+                        CERROR("Can not getattr child "DFID": rc = %d\n",
+                                PFID(lu_object_fid(child)), rc);
+                        lu_object_put(env, ec_child);
+                        break;
+                }
+                CDEBUG(D_RPCTRACE, "End getattr object "DFID"\n",
+                       PFID(lu_object_fid(child)));
+                id++;
+                lu_object_put(env, ec_child);
+        }
+
+       RETURN(rc);
+}
+
+static int echo_lookup_object(const struct lu_env *env,
+                              struct echo_device *ed,
+                              struct lu_object *ec_parent,
+                              __u64 id, int count)
+{
+        struct lu_object        *parent;
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_name          *lname = &info->eti_lname;
+        char                    *name = info->eti_name;
+        struct lu_fid           *fid = &info->eti_fid;
+        struct lu_device        *ld = ed->ed_next;
+        int                      rc = 0;
+        int                      i;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+       if (parent == NULL)
+               return -ENXIO;
+
+        /*prepare the requests*/
+        for (i = 0; i < count; i++) {
+                echo_md_build_name(lname, name, id);
+
+                CDEBUG(D_RPCTRACE, "Start lookup object "DFID" %s %p\n",
+                       PFID(lu_object_fid(parent)), lname->ln_name, parent);
+
+                rc = mdo_lookup(env, lu2md(parent), lname, fid, NULL);
+                if (rc) {
+                        CERROR("Can not lookup child %s: rc = %d\n", name, rc);
+                        break;
+                }
+                CDEBUG(D_RPCTRACE, "End lookup object "DFID" %s %p\n",
+                       PFID(lu_object_fid(parent)), lname->ln_name, parent);
+
+                id++;
+        }
+        return rc;
+}
+
+static int echo_md_destroy_internal(const struct lu_env *env,
+                                    struct echo_device *ed,
+                                    struct md_object *parent,
+                                    struct lu_name *lname,
+                                    struct md_attr *ma)
+{
+        struct lu_device   *ld = ed->ed_next;
+        struct lu_object   *ec_child;
+        struct lu_object   *child;
+        int                 rc;
+
+       ENTRY;
+
+        ec_child = echo_md_lookup(env, ed, parent, lname);
+        if (IS_ERR(ec_child)) {
+                CERROR("Can't find child %s: rc = %ld\n", lname->ln_name,
+                        PTR_ERR(ec_child));
+                RETURN(PTR_ERR(ec_child));
+        }
+
+        child = lu_object_locate(ec_child->lo_header, ld->ld_type);
+        if (child == NULL) {
+                CERROR("Can not locate the child %s\n", lname->ln_name);
+                GOTO(out_put, rc = -EINVAL);
+        }
+
+        CDEBUG(D_RPCTRACE, "Start destroy object "DFID" %s %p\n",
+               PFID(lu_object_fid(&parent->mo_lu)), lname->ln_name, parent);
+
+        rc = mdo_unlink(env, parent, lu2md(child), lname, ma);
+        if (rc) {
+                CERROR("Can not unlink child %s: rc = %d\n",
+                        lname->ln_name, rc);
+                GOTO(out_put, rc);
+        }
+        CDEBUG(D_RPCTRACE, "End destroy object "DFID" %s %p\n",
+               PFID(lu_object_fid(&parent->mo_lu)), lname->ln_name, parent);
+out_put:
+        lu_object_put(env, ec_child);
+        return rc;
+}
+
+static int echo_destroy_object(const struct lu_env *env,
+                               struct echo_device *ed,
+                               struct lu_object *ec_parent,
+                               char *name, int namelen,
+                               __u64 id, __u32 mode,
+                               int count)
+{
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_name          *lname = &info->eti_lname;
+        struct md_attr          *ma = &info->eti_ma;
+        struct lu_device        *ld = ed->ed_next;
+        struct lu_object        *parent;
+        int                      rc = 0;
+        int                      i;
+        ENTRY;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+        if (parent == NULL)
+                RETURN(-EINVAL);
+
+        memset(ma, 0, sizeof(*ma));
+        ma->ma_attr.la_mode = mode;
+        ma->ma_attr.la_valid = LA_CTIME;
+        ma->ma_attr.la_ctime = cfs_time_current_64();
+        ma->ma_need = MA_INODE;
+        ma->ma_valid = 0;
+
+        if (name != NULL) {
+                lname->ln_name = name;
+                lname->ln_namelen = namelen;
+                rc = echo_md_destroy_internal(env, ed, lu2md(parent), lname,
+                                              ma);
+               RETURN(rc);
+        }
+
+        /*prepare the requests*/
+        for (i = 0; i < count; i++) {
+                char *tmp_name = info->eti_name;
+
+                ma->ma_valid = 0;
+                echo_md_build_name(lname, tmp_name, id);
+
+                rc = echo_md_destroy_internal(env, ed, lu2md(parent), lname,
+                                              ma);
+                if (rc) {
+                        CERROR("Can not unlink child %s: rc = %d\n", name, rc);
+                        break;
+                }
+                id++;
+        }
 
-        for (i = 0; i < lsm->lsm_stripe_count; i++)
-                printk (KERN_INFO "Lustre:   @%2u:"LPX64"\n",
-                        lsm->lsm_oinfo[i].loi_ost_idx,
-                        lsm->lsm_oinfo[i].loi_id);
+       RETURN(rc);
 }
-#endif
 
-static struct ec_object *
-echo_find_object_locked (struct obd_device *obd, obd_id id)
+static struct lu_object *echo_resolve_path(const struct lu_env *env,
+                                           struct echo_device *ed, char *path,
+                                           int path_len)
 {
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct ec_object       *eco = NULL;
-        struct list_head       *el;
+        struct lu_device        *ld = ed->ed_next;
+        struct md_device        *md = lu2md_dev(ld);
+        struct echo_thread_info *info = echo_env_info(env);
+        struct lu_fid           *fid = &info->eti_fid;
+        struct lu_name          *lname = &info->eti_lname;
+        struct lu_object        *parent = NULL;
+        struct lu_object        *child = NULL;
+        int rc = 0;
+        ENTRY;
 
-        list_for_each (el, &ec->ec_objects) {
-                eco = list_entry (el, struct ec_object, eco_obj_chain);
+        /*Only support MDD layer right now*/
+        rc = md->md_ops->mdo_root_get(env, md, fid);
+        if (rc) {
+                CERROR("get root error: rc = %d\n", rc);
+                RETURN(ERR_PTR(rc));
+        }
 
-                if (eco->eco_id == id)
-                        return (eco);
+        parent = lu_object_find_at(env, &ed->ed_cl.cd_lu_dev, fid, NULL);
+        if (IS_ERR(parent)) {
+                CERROR("Can not find the parent "DFID": rc = %ld\n",
+                        PFID(fid), PTR_ERR(parent));
+                RETURN(parent);
         }
-        return (NULL);
-}
 
-static int
-echo_copyout_lsm (struct lov_stripe_md *lsm, void *ulsm, int ulsm_nob)
-{
-        int nob;
+        while (1) {
+                struct lu_object *ld_parent;
+                char *e;
 
-        nob = offsetof (struct lov_stripe_md, lsm_oinfo[lsm->lsm_stripe_count]);
-        if (nob > ulsm_nob)
-                return (-EINVAL);
+                e = strsep(&path, "/");
+                if (e == NULL)
+                        break;
 
-        if (copy_to_user (ulsm, lsm, nob))
-                return (-EFAULT);
+                if (e[0] == 0) {
+                        if (!path || path[0] == '\0')
+                                break;
+                        continue;
+                }
 
-        return (0);
+                lname->ln_name = e;
+                lname->ln_namelen = strlen(e);
+
+                ld_parent = lu_object_locate(parent->lo_header, ld->ld_type);
+                if (ld_parent == NULL) {
+                        lu_object_put(env, parent);
+                        rc = -EINVAL;
+                        break;
+                }
+
+                child = echo_md_lookup(env, ed, lu2md(ld_parent), lname);
+                lu_object_put(env, parent);
+                if (IS_ERR(child)) {
+                        rc = (int)PTR_ERR(child);
+                        CERROR("lookup %s under parent "DFID": rc = %d\n",
+                                lname->ln_name, PFID(lu_object_fid(ld_parent)),
+                                rc);
+                        break;
+                }
+                parent = child;
+        }
+        if (rc)
+                RETURN(ERR_PTR(rc));
+
+        RETURN(parent);
 }
 
-static int
-echo_copyin_lsm (struct obd_device *obd, struct lov_stripe_md *lsm,
-                 void *ulsm, int ulsm_nob)
+static void echo_ucred_init(struct lu_env *env)
 {
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        int                     nob;
+       struct lu_ucred *ucred = lu_ucred(env);
 
-        if (ulsm_nob < sizeof (*lsm))
-                return (-EINVAL);
-
-        if (copy_from_user (lsm, ulsm, sizeof (*lsm)))
-                return (-EFAULT);
+       ucred->uc_valid = UCRED_INVALID;
 
-        nob = lsm->lsm_stripe_count * sizeof (lsm->lsm_oinfo[0]);
+       ucred->uc_suppgids[0] = -1;
+       ucred->uc_suppgids[1] = -1;
 
-        if (ulsm_nob < nob ||
-            lsm->lsm_stripe_count > ec->ec_nstripes ||
-            lsm->lsm_magic != LOV_MAGIC ||
-            (lsm->lsm_stripe_size & (PAGE_SIZE - 1)) != 0 ||
-            ((__u64)lsm->lsm_stripe_size * lsm->lsm_stripe_count > ~0UL))
-                return (-EINVAL);
+       ucred->uc_uid   = ucred->uc_o_uid   = cfs_curproc_uid();
+       ucred->uc_gid   = ucred->uc_o_gid   = cfs_curproc_gid();
+       ucred->uc_fsuid = ucred->uc_o_fsuid = cfs_curproc_fsuid();
+       ucred->uc_fsgid = ucred->uc_o_fsgid = cfs_curproc_fsgid();
+       ucred->uc_cap   = cfs_curproc_cap_pack();
 
-        if (copy_from_user(lsm->lsm_oinfo,
-                           ((struct lov_stripe_md *)ulsm)->lsm_oinfo, nob))
-                return (-EFAULT);
+       /* remove fs privilege for non-root user. */
+       if (ucred->uc_fsuid)
+               ucred->uc_cap &= ~CFS_CAP_FS_MASK;
+       ucred->uc_valid = UCRED_NEW;
+}
 
-        return (0);
+static void echo_ucred_fini(struct lu_env *env)
+{
+       struct lu_ucred *ucred = lu_ucred(env);
+       ucred->uc_valid = UCRED_INIT;
 }
 
-static struct ec_object *
-echo_allocate_object (struct obd_device *obd)
+#define ECHO_MD_CTX_TAG (LCT_REMEMBER | LCT_MD_THREAD)
+#define ECHO_MD_SES_TAG (LCT_REMEMBER | LCT_SESSION)
+static int echo_md_handler(struct echo_device *ed, int command,
+                           char *path, int path_len, int id, int count,
+                           struct obd_ioctl_data *data)
 {
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct ec_object       *eco;
-        int rc;
+       struct echo_thread_info *info;
+        struct lu_device      *ld = ed->ed_next;
+        struct lu_env         *env;
+        int                    refcheck;
+        struct lu_object      *parent;
+        char                  *name = NULL;
+        int                    namelen = data->ioc_plen2;
+        int                    rc = 0;
+        ENTRY;
 
-        OBD_ALLOC(eco, sizeof (*eco));
-        if (eco == NULL)
-                return NULL;
+        if (ld == NULL) {
+                CERROR("MD echo client is not being initialized properly\n");
+                RETURN(-EINVAL);
+        }
 
-        rc = obd_alloc_memmd(ec->ec_exp, &eco->eco_lsm);
-        if (rc < 0) {
-                OBD_FREE(eco, sizeof (*eco));
-                return NULL;
+        if (strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME)) {
+                CERROR("Only support MDD layer right now!\n");
+                RETURN(-EINVAL);
         }
 
-        eco->eco_device = obd;
-        eco->eco_deleted = 0;
-        eco->eco_refcount = 0;
-        eco->eco_lsm->lsm_magic = LOV_MAGIC;
-        /* leave stripe count 0 by default */
+        env = cl_env_get(&refcheck);
+        if (IS_ERR(env))
+                RETURN(PTR_ERR(env));
+
+        rc = lu_env_refill_by_tags(env, ECHO_MD_CTX_TAG, ECHO_MD_SES_TAG);
+       if (rc != 0)
+               GOTO(out_env, rc);
+
+       /* init big_lmm buffer */
+       info = echo_env_info(env);
+       LASSERT(info->eti_big_lmm == NULL);
+       OBD_ALLOC_LARGE(info->eti_big_lmm, MIN_MD_SIZE);
+       if (info->eti_big_lmm == NULL)
+               GOTO(out_env, rc = -ENOMEM);
+       info->eti_big_lmmsize = MIN_MD_SIZE;
+
+        parent = echo_resolve_path(env, ed, path, path_len);
+        if (IS_ERR(parent)) {
+                CERROR("Can not resolve the path %s: rc = %ld\n", path,
+                        PTR_ERR(parent));
+               GOTO(out_free, rc = PTR_ERR(parent));
+        }
 
-        return (eco);
-}
+        if (namelen > 0) {
+                OBD_ALLOC(name, namelen + 1);
+                if (name == NULL)
+                       GOTO(out_put, rc = -ENOMEM);
+               if (cfs_copy_from_user(name, data->ioc_pbuf2, namelen))
+                       GOTO(out_name, rc = -EFAULT);
+        }
 
-static void
-echo_free_object (struct ec_object *eco)
-{
-        struct obd_device      *obd = eco->eco_device;
-        struct echo_client_obd *ec = &obd->u.echo_client;
+       echo_ucred_init(env);
+
+        switch (command) {
+        case ECHO_MD_CREATE:
+        case ECHO_MD_MKDIR: {
+                struct echo_thread_info *info = echo_env_info(env);
+                __u32 mode = data->ioc_obdo2.o_mode;
+                struct lu_fid *fid = &info->eti_fid;
+                int stripe_count = (int)data->ioc_obdo2.o_misc;
+                int stripe_index = (int)data->ioc_obdo2.o_stripe_idx;
+
+                fid->f_seq = data->ioc_obdo1.o_seq;
+                fid->f_oid = (__u32)data->ioc_obdo1.o_id;
+                fid->f_ver = 0;
+               /* In the function below, .hs_keycmp resolves to
+                * lu_obj_hop_keycmp() */
+               /* coverity[overrun-buffer-val] */
+                rc = echo_create_md_object(env, ed, parent, fid, name, namelen,
+                                           id, mode, count, stripe_count,
+                                           stripe_index);
+                break;
+        }
+        case ECHO_MD_DESTROY:
+        case ECHO_MD_RMDIR: {
+                __u32 mode = data->ioc_obdo2.o_mode;
 
-        LASSERT (eco->eco_refcount == 0);
-        obd_free_memmd(ec->ec_exp, &eco->eco_lsm);
-        OBD_FREE (eco, sizeof (*eco));
+                rc = echo_destroy_object(env, ed, parent, name, namelen,
+                                         id, mode, count);
+                break;
+        }
+        case ECHO_MD_LOOKUP:
+                rc = echo_lookup_object(env, ed, parent, id, count);
+                break;
+        case ECHO_MD_GETATTR:
+                rc = echo_getattr_object(env, ed, parent, id, count);
+                break;
+        case ECHO_MD_SETATTR:
+                rc = echo_setattr_object(env, ed, parent, id, count);
+                break;
+        default:
+                CERROR("unknown command %d\n", command);
+                rc = -EINVAL;
+                break;
+        }
+       echo_ucred_fini(env);
+
+out_name:
+        if (name != NULL)
+                OBD_FREE(name, namelen + 1);
+out_put:
+        lu_object_put(env, parent);
+out_free:
+       LASSERT(info->eti_big_lmm);
+       OBD_FREE_LARGE(info->eti_big_lmm, info->eti_big_lmmsize);
+       info->eti_big_lmm = NULL;
+       info->eti_big_lmmsize = 0;
+out_env:
+        cl_env_put(env, &refcheck);
+        return rc;
 }
 
-static int echo_create_object(struct obd_device *obd, int on_target,
-                              struct obdo *oa, void *ulsm, int ulsm_nob,
-                              struct obd_trans_info *oti)
+static int echo_create_object(const struct lu_env *env, struct echo_device *ed,
+                              int on_target, struct obdo *oa, void *ulsm,
+                              int ulsm_nob, struct obd_trans_info *oti)
 {
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct ec_object       *eco2;
-        struct ec_object       *eco;
-        struct lov_stripe_md   *lsm;
+        struct echo_object     *eco;
+        struct echo_client_obd *ec = ed->ed_ec;
+        struct lov_stripe_md   *lsm = NULL;
         int                     rc;
-        int                     i, idx;
+        int                     created = 0;
+        ENTRY;
 
         if ((oa->o_valid & OBD_MD_FLID) == 0 && /* no obj id */
             (on_target ||                       /* set_stripe */
              ec->ec_nstripes != 0)) {           /* LOV */
                 CERROR ("No valid oid\n");
-                return (-EINVAL);
+                RETURN(-EINVAL);
         }
 
-        if (ulsm != NULL) {
-                eco = echo_allocate_object (obd);
-                if (eco == NULL)
-                        return (-ENOMEM);
+       rc = echo_alloc_memmd(ed, &lsm);
+        if (rc < 0) {
+                CERROR("Cannot allocate md: rc = %d\n", rc);
+                GOTO(failed, rc);
+        }
 
-                lsm = eco->eco_lsm;
+        if (ulsm != NULL) {
+                int i, idx;
 
-                rc = echo_copyin_lsm (obd, lsm, ulsm, ulsm_nob);
+                rc = echo_copyin_lsm (ed, lsm, ulsm, ulsm_nob);
                 if (rc != 0)
-                        goto failed;
-
-                /* setup object ID here for !on_target and LOV hint */
-                if ((oa->o_valid & OBD_MD_FLID) != 0)
-                        eco->eco_id = lsm->lsm_object_id = oa->o_id;
+                        GOTO(failed, rc);
 
                 if (lsm->lsm_stripe_count == 0)
                         lsm->lsm_stripe_count = ec->ec_nstripes;
 
                 if (lsm->lsm_stripe_size == 0)
-                        lsm->lsm_stripe_size = PAGE_SIZE;
+                        lsm->lsm_stripe_size = CFS_PAGE_SIZE;
 
-                idx = ll_insecure_random_int();
+                idx = cfs_rand();
 
                 /* setup stripes: indices + default ids if required */
                 for (i = 0; i < lsm->lsm_stripe_count; i++) {
-                        if (lsm->lsm_oinfo[i].loi_id == 0)
-                                lsm->lsm_oinfo[i].loi_id = lsm->lsm_object_id;
+                        if (lsm->lsm_oinfo[i]->loi_id == 0)
+                                lsm->lsm_oinfo[i]->loi_id = lsm->lsm_object_id;
 
-                        lsm->lsm_oinfo[i].loi_ost_idx =
+                        lsm->lsm_oinfo[i]->loi_ost_idx =
                                 (idx + i) % ec->ec_nstripes;
                 }
-        } else {
-                OBD_ALLOC(eco, sizeof(*eco));
-                eco->eco_device = obd;
-                lsm = NULL;
         }
 
-        if (oa->o_id == 0)
-                oa->o_id = ++last_object_id;
-
-        if (on_target) {
-                /* XXX get some filter group constants */
-                oa->o_gr = 2;
-                oa->o_valid |= OBD_MD_FLGROUP;
-                rc = obd_create(ec->ec_exp, oa, &lsm, oti);
-                if (rc != 0)
-                        goto failed;
+        /* setup object ID here for !on_target and LOV hint */
+        if (oa->o_valid & OBD_MD_FLID)
+                lsm->lsm_object_id = oa->o_id;
 
-                /* See what object ID we were given */
-                eco->eco_id = oa->o_id = lsm->lsm_object_id;
-                oa->o_valid |= OBD_MD_FLID;
+        if (lsm->lsm_object_id == 0)
+                lsm->lsm_object_id = ++last_object_id;
 
-                LASSERT(eco->eco_lsm == NULL || eco->eco_lsm == lsm);
-                eco->eco_lsm = lsm;
+        rc = 0;
+        if (on_target) {
+                /* Only echo objects are allowed to be created */
+                LASSERT((oa->o_valid & OBD_MD_FLGROUP) &&
+                        (oa->o_seq == FID_SEQ_ECHO));
+                rc = obd_create(env, ec->ec_exp, oa, &lsm, oti);
+                if (rc != 0) {
+                        CERROR("Cannot create objects: rc = %d\n", rc);
+                        GOTO(failed, rc);
+                }
+                created = 1;
         }
 
-        spin_lock (&ec->ec_lock);
-
-        eco2 = echo_find_object_locked (obd, oa->o_id);
-        if (eco2 != NULL) {                     /* conflict */
-                spin_unlock (&ec->ec_lock);
-
-                CERROR ("Can't create object id "LPX64": id already exists%s\n",
-                        oa->o_id, on_target ? " (undoing create)" : "");
-
-                if (on_target)
-                        obd_destroy(ec->ec_exp, oa, lsm, oti);
+        /* See what object ID we were given */
+        oa->o_id = lsm->lsm_object_id;
+        oa->o_valid |= OBD_MD_FLID;
 
-                rc = -EEXIST;
-                goto failed;
-        }
+        eco = cl_echo_object_find(ed, &lsm);
+        if (IS_ERR(eco))
+                GOTO(failed, rc = PTR_ERR(eco));
+        cl_echo_object_put(eco);
 
-        list_add (&eco->eco_obj_chain, &ec->ec_objects);
-        spin_unlock (&ec->ec_lock);
-        CDEBUG (D_INFO,
-                "created %p: "LPX64"=%u#%u@%u refs %d del %d\n",
-                eco, eco->eco_id,
-                eco->eco_lsm->lsm_stripe_size,
-                eco->eco_lsm->lsm_stripe_count,
-                eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
-                eco->eco_refcount, eco->eco_deleted);
-        return (0);
+        CDEBUG(D_INFO, "oa->o_id = %lx\n", (long)oa->o_id);
+        EXIT;
 
  failed:
-        echo_free_object (eco);
+        if (created && rc)
+                obd_destroy(env, ec->ec_exp, oa, lsm, oti, NULL, NULL);
+        if (lsm)
+               echo_free_memmd(ed, &lsm);
+        if (rc)
+                CERROR("create object failed with: rc = %d\n", rc);
         return (rc);
 }
 
-static int
-echo_get_object (struct ec_object **ecop, struct obd_device *obd,
-                 struct obdo *oa)
+static int echo_get_object(struct echo_object **ecop, struct echo_device *ed,
+                           struct obdo *oa)
 {
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct ec_object       *eco;
-        struct ec_object       *eco2;
+        struct lov_stripe_md   *lsm = NULL;
+        struct echo_object     *eco;
         int                     rc;
+        ENTRY;
 
         if ((oa->o_valid & OBD_MD_FLID) == 0 ||
-            oa->o_id == 0)                      /* disallow use of object id 0 */
+            oa->o_id == 0)  /* disallow use of object id 0 */
         {
                 CERROR ("No valid oid\n");
-                return (-EINVAL);
-        }
-
-        spin_lock (&ec->ec_lock);
-        eco = echo_find_object_locked (obd, oa->o_id);
-        if (eco != NULL) {
-                if (eco->eco_deleted)           /* being deleted */
-                        return (-EAGAIN);       /* (see comment in cleanup) */
-
-                eco->eco_refcount++;
-                spin_unlock (&ec->ec_lock);
-                *ecop = eco;
-                CDEBUG (D_INFO,
-                        "found %p: "LPX64"=%u#%u@%u refs %d del %d\n",
-                        eco, eco->eco_id,
-                        eco->eco_lsm->lsm_stripe_size,
-                        eco->eco_lsm->lsm_stripe_count,
-                        eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
-                        eco->eco_refcount, eco->eco_deleted);
-                return (0);
+                RETURN(-EINVAL);
         }
-        spin_unlock (&ec->ec_lock);
-
-        if (ec->ec_nstripes != 0)               /* striping required */
-                return (-ENOENT);
 
-        eco = echo_allocate_object (obd);
-        if (eco == NULL)
-                return (-ENOMEM);
-
-        eco->eco_id = eco->eco_lsm->lsm_object_id = oa->o_id;
+       rc = echo_alloc_memmd(ed, &lsm);
+        if (rc < 0)
+                RETURN(rc);
 
-        spin_lock (&ec->ec_lock);
+        lsm->lsm_object_id = oa->o_id;
+        if (oa->o_valid & OBD_MD_FLGROUP)
+                lsm->lsm_object_seq = oa->o_seq;
+        else
+                lsm->lsm_object_seq = FID_SEQ_ECHO;
 
-        eco2 = echo_find_object_locked (obd, oa->o_id);
-        if (eco2 == NULL) {                     /* didn't race */
-                list_add (&eco->eco_obj_chain, &ec->ec_objects);
-                spin_unlock (&ec->ec_lock);
-                eco->eco_refcount = 1;
+        rc = 0;
+        eco = cl_echo_object_find(ed, &lsm);
+        if (!IS_ERR(eco))
                 *ecop = eco;
-                CDEBUG (D_INFO,
-                        "created %p: "LPX64"=%u#%u@%d refs %d del %d\n",
-                        eco, eco->eco_id,
-                        eco->eco_lsm->lsm_stripe_size,
-                        eco->eco_lsm->lsm_stripe_count,
-                        eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
-                        eco->eco_refcount, eco->eco_deleted);
-                return (0);
-        }
-
-        if (eco2->eco_deleted)
-                rc = -EAGAIN;                   /* lose race */
-        else {
-                eco2->eco_refcount++;           /* take existing */
-                *ecop = eco2;
-                rc = 0;
-                LASSERT (eco2->eco_id == eco2->eco_lsm->lsm_object_id);
-                CDEBUG (D_INFO,
-                        "found(2) %p: "LPX64"=%u#%u@%d refs %d del %d\n",
-                        eco2, eco2->eco_id,
-                        eco2->eco_lsm->lsm_stripe_size,
-                        eco2->eco_lsm->lsm_stripe_count,
-                        eco2->eco_lsm->lsm_oinfo[0].loi_ost_idx,
-                        eco2->eco_refcount, eco2->eco_deleted);
-        }
-
-        spin_unlock (&ec->ec_lock);
-
-        echo_free_object (eco);
-        return (rc);
+        else
+                rc = PTR_ERR(eco);
+        if (lsm)
+               echo_free_memmd(ed, &lsm);
+        RETURN(rc);
 }
 
-static void
-echo_put_object (struct ec_object *eco)
+static void echo_put_object(struct echo_object *eco)
 {
-        struct obd_device      *obd = eco->eco_device;
-        struct echo_client_obd *ec = &obd->u.echo_client;
-
-        /* Release caller's ref on the object.
-         * delete => mark for deletion when last ref goes
-         */
-
-        spin_lock (&ec->ec_lock);
-
-        eco->eco_refcount--;
-        LASSERT (eco->eco_refcount >= 0);
-
-        CDEBUG(D_INFO, "put %p: "LPX64"=%u#%u@%d refs %d del %d\n",
-               eco, eco->eco_id,
-               eco->eco_lsm->lsm_stripe_size,
-               eco->eco_lsm->lsm_stripe_count,
-               eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
-               eco->eco_refcount, eco->eco_deleted);
-
-        if (eco->eco_refcount != 0 || !eco->eco_deleted) {
-                spin_unlock (&ec->ec_lock);
-                return;
-        }
-
-        spin_unlock (&ec->ec_lock);
-
-        /* NB leave obj in the object list.  We must prevent anyone from
-         * attempting to enqueue on this object number until we can be
-         * sure there will be no more lock callbacks.
-         */
-        obd_cancel_unused(ec->ec_exp, eco->eco_lsm, 0, NULL);
-
-        /* now we can let it go */
-        spin_lock (&ec->ec_lock);
-        list_del (&eco->eco_obj_chain);
-        spin_unlock (&ec->ec_lock);
-
-        LASSERT (eco->eco_refcount == 0);
-
-        echo_free_object (eco);
+        if (cl_echo_object_put(eco))
+                CERROR("echo client: drop an object failed");
 }
 
 static void
@@ -421,13 +2394,13 @@ echo_get_stripe_off_id (struct lov_stripe_md *lsm, obd_off *offp, obd_id *idp)
 
         stripe_index = woffset / stripe_size;
 
-        *idp = lsm->lsm_oinfo[stripe_index].loi_id;
+        *idp = lsm->lsm_oinfo[stripe_index]->loi_id;
         *offp = offset * stripe_size + woffset % stripe_size;
 }
 
-static void 
-echo_client_page_debug_setup(struct lov_stripe_md *lsm, 
-                             struct page *page, int rw, obd_id id, 
+static void
+echo_client_page_debug_setup(struct lov_stripe_md *lsm,
+                             cfs_page_t *page, int rw, obd_id id,
                              obd_off offset, obd_off count)
 {
         char    *addr;
@@ -436,11 +2409,11 @@ echo_client_page_debug_setup(struct lov_stripe_md *lsm,
         int      delta;
 
         /* no partial pages on the client */
-        LASSERT(count == PAGE_SIZE);
+        LASSERT(count == CFS_PAGE_SIZE);
 
-        addr = kmap(page);
+        addr = cfs_kmap(page);
 
-        for (delta = 0; delta < PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
+        for (delta = 0; delta < CFS_PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
                 if (rw == OBD_BRW_WRITE) {
                         stripe_off = offset + delta;
                         stripe_id = id;
@@ -449,474 +2422,165 @@ echo_client_page_debug_setup(struct lov_stripe_md *lsm,
                         stripe_off = 0xdeadbeef00c0ffeeULL;
                         stripe_id = 0xdeadbeef00c0ffeeULL;
                 }
-                block_debug_setup(addr + delta, OBD_ECHO_BLOCK_SIZE, 
-                                  stripe_off, stripe_id);
-        }
-
-        kunmap(page);
-}
-
-static int
-echo_client_page_debug_check(struct lov_stripe_md *lsm, 
-                             struct page *page, obd_id id, 
-                             obd_off offset, obd_off count)
-{
-        obd_off stripe_off;
-        obd_id  stripe_id;
-        char   *addr;
-        int     delta;
-        int     rc;
-        int     rc2;
-
-        /* no partial pages on the client */
-        LASSERT(count == PAGE_SIZE);
-
-        addr = kmap(page);
-
-        for (rc = delta = 0; delta < PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
-                stripe_off = offset + delta;
-                stripe_id = id;
-                echo_get_stripe_off_id (lsm, &stripe_off, &stripe_id);
-
-                rc2 = block_debug_check("test_brw", 
-                                        addr + delta, OBD_ECHO_BLOCK_SIZE, 
-                                        stripe_off, stripe_id);
-                if (rc2 != 0)
-                        rc = rc2;
-        }
-
-        kunmap(page);
-        return rc;
-}
-
-static int echo_client_kbrw(struct obd_device *obd, int rw, struct obdo *oa,
-                            struct lov_stripe_md *lsm, obd_off offset,
-                            obd_size count, struct obd_trans_info *oti)
-{
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        obd_count               npages;
-        struct brw_page        *pga;
-        struct brw_page        *pgp;
-        obd_off                 off;
-        int                     i;
-        int                     rc;
-        int                     verify = 0;
-        int                     gfp_mask;
-
-        /* oa_id == ECHO_PERSISTENT_OBJID => speed test (no verification).
-         * oa & 1                         => use HIGHMEM */
-
-        verify = (oa->o_id) != ECHO_PERSISTENT_OBJID;
-        gfp_mask = ((oa->o_id & 2) == 0) ? GFP_KERNEL : GFP_HIGHUSER;
-
-        LASSERT(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ);
-
-        if (count <= 0 ||
-            (count & (PAGE_SIZE - 1)) != 0 ||
-            (lsm != NULL &&
-             lsm->lsm_object_id != oa->o_id))
-                return (-EINVAL);
-
-        /* XXX think again with misaligned I/O */
-        npages = count >> PAGE_SHIFT;
-
-        OBD_ALLOC(pga, npages * sizeof(*pga));
-        if (pga == NULL)
-                return (-ENOMEM);
-
-        for (i = 0, pgp = pga, off = offset;
-             i < npages;
-             i++, pgp++, off += PAGE_SIZE) {
-
-                LASSERT (pgp->pg == NULL);      /* for cleanup */
-
-                rc = -ENOMEM;
-                pgp->pg = alloc_pages (gfp_mask, 0);
-                if (pgp->pg == NULL)
-                        goto out;
-
-                pgp->count = PAGE_SIZE;
-                pgp->off = off;
-                pgp->flag = 0;
-
-                if (verify)
-                        echo_client_page_debug_setup(lsm, pgp->pg, rw, 
-                                                     oa->o_id, off, pgp->count);
-        }
-
-        rc = obd_brw(rw, ec->ec_exp, oa, lsm, npages, pga, oti);
-
- out:
-        if (rc != 0 || rw != OBD_BRW_READ)
-                verify = 0;
-
-        for (i = 0, pgp = pga; i < npages; i++, pgp++) {
-                if (pgp->pg == NULL)
-                        continue;
-
-                if (verify) {
-                        int vrc;
-                        vrc = echo_client_page_debug_check(lsm, pgp->pg, oa->o_id,
-                                                           pgp->off, pgp->count);
-                        if (vrc != 0 && rc == 0)
-                                rc = vrc;
-                }
-                __free_pages(pgp->pg, 0);
-        }
-        OBD_FREE(pga, npages * sizeof(*pga));
-        return (rc);
-}
-
-#ifdef __KERNEL__
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
-static int echo_client_ubrw(struct obd_device *obd, int rw,
-                            struct obdo *oa, struct lov_stripe_md *lsm,
-                            obd_off offset, obd_size count, char *buffer,
-                            struct obd_trans_info *oti)
-{
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        obd_count               npages;
-        struct brw_page        *pga;
-        struct brw_page        *pgp;
-        obd_off                 off;
-        struct kiobuf          *kiobuf;
-        int                     i;
-        int                     rc;
-
-        LASSERT (rw == OBD_BRW_WRITE ||
-                 rw == OBD_BRW_READ);
-
-        /* NB: for now, only whole pages, page aligned */
-
-        if (count <= 0 ||
-            ((long)buffer & (PAGE_SIZE - 1)) != 0 ||
-            (count & (PAGE_SIZE - 1)) != 0 ||
-            (lsm != NULL && lsm->lsm_object_id != oa->o_id))
-                return (-EINVAL);
-
-        /* XXX think again with misaligned I/O */
-        npages = count >> PAGE_SHIFT;
-
-        OBD_ALLOC(pga, npages * sizeof(*pga));
-        if (pga == NULL)
-                return (-ENOMEM);
-
-        rc = alloc_kiovec (1, &kiobuf);
-        if (rc != 0)
-                goto out_1;
-
-        rc = map_user_kiobuf ((rw == OBD_BRW_READ) ? READ : WRITE,
-                              kiobuf, (unsigned long)buffer, count);
-        if (rc != 0)
-                goto out_2;
-
-        LASSERT (kiobuf->offset == 0);
-        LASSERT (kiobuf->nr_pages == npages);
-
-        for (i = 0, off = offset, pgp = pga;
-             i < npages;
-             i++, off += PAGE_SIZE, pgp++) {
-                pgp->off = off;
-                pgp->pg = kiobuf->maplist[i];
-                pgp->count = PAGE_SIZE;
-                pgp->flag = 0;
-        }
-
-        rc = obd_brw(rw, ec->ec_exp, oa, lsm, npages, pga, oti);
-
-        //        if (rw == OBD_BRW_READ)
-        //                mark_dirty_kiobuf (kiobuf, count);
-
-        unmap_kiobuf (kiobuf);
- out_2:
-        free_kiovec (1, &kiobuf);
- out_1:
-        OBD_FREE(pga, npages * sizeof(*pga));
-        return (rc);
-}
-#else
-static int echo_client_ubrw(struct obd_device *obd, int rw,
-                            struct obdo *oa, struct lov_stripe_md *lsm,
-                            obd_off offset, obd_size count, char *buffer,
-                            struct obd_trans_info *oti)
-{
-#warning "echo_client_ubrw() needs to be ported on 2.6 yet"
-        LBUG();
-        return 0;
-}
-#endif
-#endif
-
-struct echo_async_state;
-
-#define EAP_MAGIC 79277927
-struct echo_async_page {
-        int                     eap_magic;
-        struct page             *eap_page;
-        void                    *eap_cookie;
-        obd_off                 eap_off;
-        struct echo_async_state *eap_eas;
-        struct list_head        eap_item;
-};
-
-struct echo_async_state {
-        spinlock_t              eas_lock;
-        obd_off                 eas_next_offset;
-        obd_off                 eas_end_offset;
-        int                     eas_in_flight;
-        int                     eas_rc;
-        wait_queue_head_t       eas_waitq;
-        struct list_head        eas_avail;
-        struct obdo             eas_oa;
-        struct lov_stripe_md    *eas_lsm;
-};
-
-static int eas_should_wake(struct echo_async_state *eas)
-{
-        unsigned long flags;
-        int rc = 0;
-        spin_lock_irqsave(&eas->eas_lock, flags);
-        if (eas->eas_rc == 0 && !list_empty(&eas->eas_avail))
-            rc = 1;
-        spin_unlock_irqrestore(&eas->eas_lock, flags);
-        return rc;
-};
-
-struct echo_async_page *eap_from_cookie(void *cookie)
-{
-        struct echo_async_page *eap = cookie;
-        if (eap->eap_magic != EAP_MAGIC)
-                return ERR_PTR(-EINVAL);
-        return eap;
-};
+                block_debug_setup(addr + delta, OBD_ECHO_BLOCK_SIZE,
+                                  stripe_off, stripe_id);
+        }
 
-static int ec_ap_make_ready(void *data, int cmd)
-{
-        /* our pages are issued ready */
-        LBUG();
-        return 0;
-}
-static int ec_ap_refresh_count(void *data, int cmd)
-{
-        /* our pages are issued with a stable count */
-        LBUG();
-        return PAGE_SIZE;
+        cfs_kunmap(page);
 }
-static void ec_ap_fill_obdo(void *data, int cmd, struct obdo *oa)
+
+static int echo_client_page_debug_check(struct lov_stripe_md *lsm,
+                                        cfs_page_t *page, obd_id id,
+                                        obd_off offset, obd_off count)
 {
-        struct echo_async_page *eap;
-        eap = eap_from_cookie(data);
-        if (IS_ERR(eap))
-                return;
+        obd_off stripe_off;
+        obd_id  stripe_id;
+        char   *addr;
+        int     delta;
+        int     rc;
+        int     rc2;
 
-        memcpy(oa, &eap->eap_eas->eas_oa, sizeof(*oa));
-}
+        /* no partial pages on the client */
+        LASSERT(count == CFS_PAGE_SIZE);
 
-static void ec_ap_completion(void *data, int cmd, struct obdo *oa, int rc)
-{
-        struct echo_async_page *eap = eap_from_cookie(data);
-        struct echo_async_state *eas;
-        unsigned long flags;
+        addr = cfs_kmap(page);
 
-        if (IS_ERR(eap))
-                return;
-        eas = eap->eap_eas;
-
-        if (cmd == OBD_BRW_READ &&
-            eas->eas_oa.o_id != ECHO_PERSISTENT_OBJID)
-                echo_client_page_debug_check(eas->eas_lsm, eap->eap_page, 
-                                             eas->eas_oa.o_id, eap->eap_off,
-                                             PAGE_SIZE);
-
-        spin_lock_irqsave(&eas->eas_lock, flags);
-        if (rc && !eas->eas_rc)
-                eas->eas_rc = rc;
-        eas->eas_in_flight--;
-        list_add(&eap->eap_item, &eas->eas_avail);
-        wake_up(&eas->eas_waitq);
-        spin_unlock_irqrestore(&eas->eas_lock, flags);
-}
-
-static struct obd_async_page_ops ec_async_page_ops = {
-        .ap_make_ready =        ec_ap_make_ready,
-        .ap_refresh_count =     ec_ap_refresh_count,
-        .ap_fill_obdo =         ec_ap_fill_obdo,
-        .ap_completion =        ec_ap_completion,
-};
+        for (rc = delta = 0; delta < CFS_PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
+                stripe_off = offset + delta;
+                stripe_id = id;
+                echo_get_stripe_off_id (lsm, &stripe_off, &stripe_id);
+
+                rc2 = block_debug_check("test_brw",
+                                        addr + delta, OBD_ECHO_BLOCK_SIZE,
+                                        stripe_off, stripe_id);
+                if (rc2 != 0) {
+                        CERROR ("Error in echo object "LPX64"\n", id);
+                        rc = rc2;
+                }
+        }
+
+        cfs_kunmap(page);
+        return rc;
+}
 
-static int echo_client_async_page(struct obd_export *exp, int rw,
-                                   struct obdo *oa, struct lov_stripe_md *lsm,
-                                   obd_off offset, obd_size count,
-                                   obd_size batching)
+static int echo_client_kbrw(struct echo_device *ed, int rw, struct obdo *oa,
+                            struct echo_object *eco, obd_off offset,
+                            obd_size count, int async,
+                            struct obd_trans_info *oti)
 {
-        obd_count npages, i;
-        struct echo_async_page *eap;
-        struct echo_async_state eas;
-        struct list_head *pos, *n;
-        int rc = 0;
-        unsigned long flags;
-        LIST_HEAD(pages);
-#if 0
+        struct lov_stripe_md   *lsm = eco->eo_lsm;
+        obd_count               npages;
+        struct brw_page        *pga;
+        struct brw_page        *pgp;
+        cfs_page_t            **pages;
+        obd_off                 off;
+        int                     i;
+        int                     rc;
         int                     verify;
         int                     gfp_mask;
-        /* oa_id  == 0    => speed test (no verification) else...
-         * oa & 1         => use HIGHMEM
-         */
-        verify = (oa->o_id != 0);
-        gfp_mask = ((oa->o_id & 1) == 0) ? GFP_KERNEL : GFP_HIGHUSER;
-#endif
+        int                     brw_flags = 0;
+        ENTRY;
+
+        verify = ((oa->o_id) != ECHO_PERSISTENT_OBJID &&
+                  (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
+                  (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
+
+        gfp_mask = ((oa->o_id & 2) == 0) ? CFS_ALLOC_STD : CFS_ALLOC_HIGHUSER;
 
         LASSERT(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ);
+        LASSERT(lsm != NULL);
+        LASSERT(lsm->lsm_object_id == oa->o_id);
 
         if (count <= 0 ||
-            (count & (PAGE_SIZE - 1)) != 0 ||
-            (lsm != NULL &&
-             lsm->lsm_object_id != oa->o_id))
-                return (-EINVAL);
+            (count & (~CFS_PAGE_MASK)) != 0)
+                RETURN(-EINVAL);
 
         /* XXX think again with misaligned I/O */
-        npages = batching >> PAGE_SHIFT;
-
-        memcpy(&eas.eas_oa, oa, sizeof(*oa));
-        eas.eas_next_offset = offset;
-        eas.eas_end_offset = offset + count;
-        spin_lock_init(&eas.eas_lock);
-        init_waitqueue_head(&eas.eas_waitq);
-        eas.eas_in_flight = 0;
-        eas.eas_rc = 0;
-        eas.eas_lsm = lsm;
-        INIT_LIST_HEAD(&eas.eas_avail);
-
-        /* prepare the group of pages that we're going to be keeping
-         * in flight */
-        for (i = 0; i < npages; i++) {
-                struct page *page = alloc_page(GFP_KERNEL);
-                if (page == NULL)
-                        GOTO(out, rc = -ENOMEM);
+        npages = count >> CFS_PAGE_SHIFT;
 
-                page->private = 0;
-                list_add_tail(&PAGE_LIST(page), &pages);
+        if (rw == OBD_BRW_WRITE)
+                brw_flags = OBD_BRW_ASYNC;
 
-                OBD_ALLOC(eap, sizeof(*eap));
-                if (eap == NULL)
-                        GOTO(out, rc = -ENOMEM);
+        OBD_ALLOC(pga, npages * sizeof(*pga));
+        if (pga == NULL)
+                RETURN(-ENOMEM);
 
-                eap->eap_magic = EAP_MAGIC;
-                eap->eap_page = page;
-                eap->eap_eas = &eas;
-                page->private = (unsigned long)eap;
-                list_add_tail(&eap->eap_item, &eas.eas_avail);
+        OBD_ALLOC(pages, npages * sizeof(*pages));
+        if (pages == NULL) {
+                OBD_FREE(pga, npages * sizeof(*pga));
+                RETURN(-ENOMEM);
         }
 
-        /* first we spin queueing io and being woken by its completion */
-        spin_lock_irqsave(&eas.eas_lock, flags);
-        for(;;) {
-                int rc;
+        for (i = 0, pgp = pga, off = offset;
+             i < npages;
+             i++, pgp++, off += CFS_PAGE_SIZE) {
 
-                /* sleep until we have a page to send */
-                spin_unlock_irqrestore(&eas.eas_lock, flags);
-                rc = wait_event_interruptible(eas.eas_waitq, 
-                                              eas_should_wake(&eas));
-                spin_lock_irqsave(&eas.eas_lock, flags);
-                if (rc && !eas.eas_rc)
-                        eas.eas_rc = rc;
-                if (eas.eas_rc)
-                        break;
-                if (list_empty(&eas.eas_avail))
-                        continue;
-                eap = list_entry(eas.eas_avail.next, struct echo_async_page,
-                                 eap_item);
-                list_del(&eap->eap_item);
-                spin_unlock_irqrestore(&eas.eas_lock, flags);
-
-                /* unbind the eap from its old page offset */
-                if (eap->eap_cookie != NULL) {
-                        obd_teardown_async_page(exp, lsm, NULL, 
-                                                eap->eap_cookie);
-                        eap->eap_cookie = NULL;
-                }
+                LASSERT (pgp->pg == NULL);      /* for cleanup */
 
-                eas.eas_next_offset += PAGE_SIZE;
-                eap->eap_off = eas.eas_next_offset;
+                rc = -ENOMEM;
+                OBD_PAGE_ALLOC(pgp->pg, gfp_mask);
+                if (pgp->pg == NULL)
+                        goto out;
 
-                rc = obd_prep_async_page(exp, lsm, NULL, eap->eap_page,
-                                         eap->eap_off, &ec_async_page_ops,
-                                         eap, &eap->eap_cookie);
-                if (rc) {
-                        spin_lock_irqsave(&eas.eas_lock, flags);
-                        eas.eas_rc = rc;
-                        break;
-                }
+                pages[i] = pgp->pg;
+                pgp->count = CFS_PAGE_SIZE;
+                pgp->off = off;
+                pgp->flag = brw_flags;
 
-                if (oa->o_id != ECHO_PERSISTENT_OBJID)
-                        echo_client_page_debug_setup(lsm, eap->eap_page, rw, 
-                                                     oa->o_id, 
-                                                     eap->eap_off, PAGE_SIZE);
-
-                /* always asserts urgent, which isn't quite right */
-                rc = obd_queue_async_io(exp, lsm, NULL, eap->eap_cookie,
-                                        rw, 0, PAGE_SIZE, 0,
-                                        ASYNC_READY | ASYNC_URGENT |
-                                        ASYNC_COUNT_STABLE);
-                spin_lock_irqsave(&eas.eas_lock, flags);
-                if (rc && !eas.eas_rc) {
-                        eas.eas_rc = rc;
-                        break;
-                }
-                eas.eas_in_flight++;
-                if (eas.eas_next_offset == eas.eas_end_offset)
-                        break;
-        } 
+                if (verify)
+                        echo_client_page_debug_setup(lsm, pgp->pg, rw,
+                                                     oa->o_id, off, pgp->count);
+        }
 
-        /* still hold the eas_lock here.. */
+        /* brw mode can only be used at client */
+        LASSERT(ed->ed_next != NULL);
+        rc = cl_echo_object_brw(eco, rw, offset, pages, npages, async);
 
-        /* now we just spin waiting for all the rpcs to complete */
-        while(eas.eas_in_flight) {
-                spin_unlock_irqrestore(&eas.eas_lock, flags);
-                wait_event_interruptible(eas.eas_waitq, 
-                                         eas.eas_in_flight == 0);
-                spin_lock_irqsave(&eas.eas_lock, flags);
-        }
-        spin_unlock_irqrestore(&eas.eas_lock, flags);
+ out:
+        if (rc != 0 || rw != OBD_BRW_READ)
+                verify = 0;
 
-out:
-        list_for_each_safe(pos, n, &pages) {
-                struct page *page = list_entry(pos, struct page, 
-                                               PAGE_LIST_ENTRY);
-
-                list_del(&PAGE_LIST(page));
-                if (page->private != 0) {
-                        eap = (struct echo_async_page *)page->private;
-                        if (eap->eap_cookie != NULL)
-                                obd_teardown_async_page(exp, lsm, NULL, 
-                                                        eap->eap_cookie);
-                        OBD_FREE(eap, sizeof(*eap));
+        for (i = 0, pgp = pga; i < npages; i++, pgp++) {
+                if (pgp->pg == NULL)
+                        continue;
+
+                if (verify) {
+                        int vrc;
+                        vrc = echo_client_page_debug_check(lsm, pgp->pg, oa->o_id,
+                                                           pgp->off, pgp->count);
+                        if (vrc != 0 && rc == 0)
+                                rc = vrc;
                 }
-                __free_page(page);
+                OBD_PAGE_FREE(pgp->pg);
         }
-
+        OBD_FREE(pga, npages * sizeof(*pga));
+        OBD_FREE(pages, npages * sizeof(*pages));
         RETURN(rc);
 }
 
-static int echo_client_prep_commit(struct obd_export *exp, int rw,
-                                   struct obdo *oa, struct lov_stripe_md *lsm,
-                                   obd_off offset, obd_size count,  
-                                   obd_size batch, struct obd_trans_info *oti)
+static int echo_client_prep_commit(const struct lu_env *env,
+                                  struct obd_export *exp, int rw,
+                                  struct obdo *oa, struct echo_object *eco,
+                                  obd_off offset, obd_size count,
+                                  obd_size batch, struct obd_trans_info *oti,
+                                  int async)
 {
+        struct lov_stripe_md *lsm = eco->eo_lsm;
         struct obd_ioobj ioo;
         struct niobuf_local *lnb;
         struct niobuf_remote *rnb;
         obd_off off;
         obd_size npages, tot_pages;
-        int i, ret = 0;
+       int i, ret = 0, brw_flags = 0;
+
         ENTRY;
 
-        if (count <= 0 || (count & (PAGE_SIZE - 1)) != 0 ||
+        if (count <= 0 || (count & (~CFS_PAGE_MASK)) != 0 ||
             (lsm != NULL && lsm->lsm_object_id != oa->o_id))
                 RETURN(-EINVAL);
 
-        npages = batch >> PAGE_SHIFT;
-        tot_pages = count >> PAGE_SHIFT;
+        npages = batch >> CFS_PAGE_SHIFT;
+        tot_pages = count >> CFS_PAGE_SHIFT;
 
         OBD_ALLOC(lnb, npages * sizeof(struct niobuf_local));
         OBD_ALLOC(rnb, npages * sizeof(struct niobuf_remote));
@@ -924,35 +2588,48 @@ static int echo_client_prep_commit(struct obd_export *exp, int rw,
         if (lnb == NULL || rnb == NULL)
                 GOTO(out, ret = -ENOMEM);
 
+       if (rw == OBD_BRW_WRITE && async)
+               brw_flags |= OBD_BRW_ASYNC;
+
         obdo_to_ioobj(oa, &ioo);
 
         off = offset;
 
         for(; tot_pages; tot_pages -= npages) {
+                int lpages;
+
                 if (tot_pages < npages)
                         npages = tot_pages;
 
-                for (i = 0; i < npages; i++, off += PAGE_SIZE) {
+                for (i = 0; i < npages; i++, off += CFS_PAGE_SIZE) {
                         rnb[i].offset = off;
-                        rnb[i].len = PAGE_SIZE;
+                        rnb[i].len = CFS_PAGE_SIZE;
+                       rnb[i].flags = brw_flags;
                 }
 
-                /* XXX this can't be the best.. */
-                memset(oti, 0, sizeof(*oti));
                 ioo.ioo_bufcnt = npages;
+                oti->oti_transno = 0;
 
-                ret = obd_preprw(rw, exp, oa, 1, &ioo, npages, rnb, lnb, oti);
+                lpages = npages;
+               ret = obd_preprw(env, rw, exp, oa, 1, &ioo, rnb, &lpages,
+                                 lnb, oti, NULL);
                 if (ret != 0)
                         GOTO(out, ret);
+                LASSERT(lpages == npages);
 
-                for (i = 0; i < npages; i++) {
-                        struct page *page = lnb[i].page;
+                for (i = 0; i < lpages; i++) {
+                        cfs_page_t *page = lnb[i].page;
 
                         /* read past eof? */
                         if (page == NULL && lnb[i].rc == 0)
                                 continue;
 
-                        if (oa->o_id == ECHO_PERSISTENT_OBJID)
+                        if (async)
+                                lnb[i].flags |= OBD_BRW_ASYNC;
+
+                        if (oa->o_id == ECHO_PERSISTENT_OBJID ||
+                            (oa->o_valid & OBD_MD_FLFLAGS) == 0 ||
+                            (oa->o_flags & OBD_FL_DEBUG_CHECK) == 0)
                                 continue;
 
                         if (rw == OBD_BRW_WRITE)
@@ -967,9 +2644,13 @@ static int echo_client_prep_commit(struct obd_export *exp, int rw,
                                                              rnb[i].len);
                 }
 
-                ret = obd_commitrw(rw, exp, oa, 1, &ioo, npages, lnb, oti, ret);
+               ret = obd_commitrw(env, rw, exp, oa, 1, &ioo,
+                                  rnb, npages, lnb, oti, ret);
                 if (ret != 0)
                         GOTO(out, ret);
+
+                /* Reset oti otherwise it would confuse ldiskfs. */
+                memset(oti, 0, sizeof(*oti));
         }
 
 out:
@@ -980,51 +2661,56 @@ out:
         RETURN(ret);
 }
 
-int echo_client_brw_ioctl(int rw, struct obd_export *exp,
-                          struct obd_ioctl_data *data)
+static int echo_client_brw_ioctl(const struct lu_env *env, int rw,
+                                struct obd_export *exp,
+                                struct obd_ioctl_data *data,
+                                struct obd_trans_info *dummy_oti)
 {
         struct obd_device *obd = class_exp2obd(exp);
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct obd_trans_info dummy_oti;
-        struct ec_object *eco;
+        struct echo_device *ed = obd2echo_dev(obd);
+        struct echo_client_obd *ec = ed->ed_ec;
+        struct obdo *oa = &data->ioc_obdo1;
+        struct echo_object *eco;
         int rc;
+        int async = 1;
+        long test_mode;
         ENTRY;
 
-        rc = echo_get_object(&eco, obd, &data->ioc_obdo1);
+        LASSERT(oa->o_valid & OBD_MD_FLGROUP);
+
+        rc = echo_get_object(&eco, ed, oa);
         if (rc)
                 RETURN(rc);
 
-        memset(&dummy_oti, 0, sizeof(dummy_oti));
+        oa->o_valid &= ~OBD_MD_FLHANDLE;
+
+       /* OFD/obdfilter works only via prep/commit */
+        test_mode = (long)data->ioc_pbuf1;
+        if (test_mode == 1)
+                async = 0;
 
-        data->ioc_obdo1.o_valid &= ~OBD_MD_FLHANDLE;
-        data->ioc_obdo1.o_valid |= OBD_MD_FLGROUP;
-        data->ioc_obdo1.o_gr = 2;
+        if (ed->ed_next == NULL && test_mode != 3) {
+                test_mode = 3;
+                data->ioc_plen1 = data->ioc_count;
+        }
+
+        /* Truncate batch size to maximum */
+        if (data->ioc_plen1 > PTLRPC_MAX_BRW_SIZE)
+                data->ioc_plen1 = PTLRPC_MAX_BRW_SIZE;
 
-        switch((long)data->ioc_pbuf1) {
+        switch (test_mode) {
         case 1:
-                if (data->ioc_pbuf2 == NULL) { // NULL user data pointer
-                        rc = echo_client_kbrw(obd, rw, &data->ioc_obdo1,
-                                              eco->eco_lsm, data->ioc_offset,
-                                              data->ioc_count, &dummy_oti);
-                } else {
-#ifdef __KERNEL__
-                        rc = echo_client_ubrw(obd, rw, &data->ioc_obdo1,
-                                              eco->eco_lsm, data->ioc_offset,
-                                              data->ioc_count, data->ioc_pbuf2,
-                                              &dummy_oti);
-#endif
-                }
-                break;
+                /* fall through */
         case 2:
-                rc = echo_client_async_page(ec->ec_exp, rw, &data->ioc_obdo1,
-                                           eco->eco_lsm, data->ioc_offset,
-                                           data->ioc_count, data->ioc_plen1);
+                rc = echo_client_kbrw(ed, rw, oa,
+                                      eco, data->ioc_offset,
+                                     data->ioc_count, async, dummy_oti);
                 break;
         case 3:
-                rc = echo_client_prep_commit(ec->ec_exp, rw, &data->ioc_obdo1,
-                                            eco->eco_lsm, data->ioc_offset,
-                                            data->ioc_count, data->ioc_plen1,
-                                            &dummy_oti);
+               rc = echo_client_prep_commit(env, ec->ec_exp, rw, oa,
+                                            eco, data->ioc_offset,
+                                            data->ioc_count, data->ioc_plen1,
+                                            dummy_oti, async);
                 break;
         default:
                 rc = -EINVAL;
@@ -1034,162 +2720,67 @@ int echo_client_brw_ioctl(int rw, struct obd_export *exp,
 }
 
 static int
-echo_ldlm_callback (struct ldlm_lock *lock, struct ldlm_lock_desc *new,
-                    void *data, int flag)
-{
-        struct ec_object       *eco = (struct ec_object *)data;
-        struct echo_client_obd *ec = &(eco->eco_device->u.echo_client);
-        struct lustre_handle    lockh;
-        struct list_head       *el;
-        int                     found = 0;
-        int                     rc;
-
-        ldlm_lock2handle (lock, &lockh);
-
-        /* #ifdef this out if we're not feeling paranoid */
-        spin_lock (&ec->ec_lock);
-        list_for_each (el, &ec->ec_objects) {
-                found = (eco == list_entry(el, struct ec_object,
-                                           eco_obj_chain));
-                if (found)
-                        break;
-        }
-        spin_unlock (&ec->ec_lock);
-        LASSERT (found);
-
-        switch (flag) {
-        case LDLM_CB_BLOCKING:
-                CDEBUG(D_INFO, "blocking callback on "LPX64", handle "LPX64"\n",
-                       eco->eco_id, lockh.cookie);
-                rc = ldlm_cli_cancel (&lockh);
-                if (rc != ELDLM_OK)
-                        CERROR ("ldlm_cli_cancel failed: %d\n", rc);
-                break;
-
-        case LDLM_CB_CANCELING:
-                CDEBUG(D_INFO, "cancel callback on "LPX64", handle "LPX64"\n",
-                       eco->eco_id, lockh.cookie);
-                break;
-
-        default:
-                LBUG ();
-        }
-
-        return (0);
-}
-
-static int
 echo_client_enqueue(struct obd_export *exp, struct obdo *oa,
                     int mode, obd_off offset, obd_size nob)
 {
-        struct obd_device      *obd = exp->exp_obd;
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct lustre_handle   *ulh = obdo_handle (oa);
-        struct ec_object       *eco;
-        struct ec_lock         *ecl;
-        int                     flags;
+        struct echo_device     *ed = obd2echo_dev(exp->exp_obd);
+        struct lustre_handle   *ulh = &oa->o_handle;
+        struct echo_object     *eco;
+        obd_off                 end;
         int                     rc;
+        ENTRY;
 
-        if (!(mode == LCK_PR || mode == LCK_PW))
-                return -EINVAL;
-
-        if ((offset & (PAGE_SIZE - 1)) != 0 ||
-            (nob & (PAGE_SIZE - 1)) != 0)
-                return -EINVAL;
+        if (ed->ed_next == NULL)
+                RETURN(-EOPNOTSUPP);
 
-        rc = echo_get_object (&eco, obd, oa);
-        if (rc != 0)
-                return rc;
+        if (!(mode == LCK_PR || mode == LCK_PW))
+                RETURN(-EINVAL);
 
-        rc = -ENOMEM;
-        OBD_ALLOC (ecl, sizeof (*ecl));
-        if (ecl == NULL)
-                goto failed_0;
+        if ((offset & (~CFS_PAGE_MASK)) != 0 ||
+            (nob & (~CFS_PAGE_MASK)) != 0)
+                RETURN(-EINVAL);
 
-        ecl->ecl_mode = mode;
-        ecl->ecl_object = eco;
-        ecl->ecl_policy.l_extent.start = offset;
-        ecl->ecl_policy.l_extent.end =
-                (nob == 0) ? ((obd_off) -1) : (offset + nob - 1);
-
-        flags = 0;
-        rc = obd_enqueue(ec->ec_exp, eco->eco_lsm, LDLM_EXTENT,
-                         &ecl->ecl_policy, mode, &flags, echo_ldlm_callback,
-                         ldlm_completion_ast, NULL, eco, sizeof(struct ost_lvb),
-                         lustre_swab_ost_lvb, &ecl->ecl_lock_handle);
+        rc = echo_get_object (&eco, ed, oa);
         if (rc != 0)
-                goto failed_1;
-
-        CDEBUG(D_INFO, "enqueue handle "LPX64"\n", ecl->ecl_lock_handle.cookie);
-
-        /* NB ecl takes object ref from echo_get_object() above */
-        spin_lock(&ec->ec_lock);
-
-        list_add(&ecl->ecl_exp_chain, &exp->exp_ec_data.eced_locks);
-        ulh->cookie = ecl->ecl_cookie = ec->ec_unique++;
-
-        spin_unlock(&ec->ec_lock);
-
-        oa->o_valid |= OBD_MD_FLHANDLE;
-        return 0;
+                RETURN(rc);
 
- failed_1:
-        OBD_FREE (ecl, sizeof (*ecl));
- failed_0:
-        echo_put_object (eco);
-        return (rc);
+        end = (nob == 0) ? ((obd_off) -1) : (offset + nob - 1);
+        rc = cl_echo_enqueue(eco, offset, end, mode, &ulh->cookie);
+        if (rc == 0) {
+                oa->o_valid |= OBD_MD_FLHANDLE;
+                CDEBUG(D_INFO, "Cookie is "LPX64"\n", ulh->cookie);
+        }
+        echo_put_object(eco);
+        RETURN(rc);
 }
 
 static int
 echo_client_cancel(struct obd_export *exp, struct obdo *oa)
 {
-        struct obd_device      *obd = exp->exp_obd;
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct lustre_handle   *ulh = obdo_handle (oa);
-        struct ec_lock         *ecl = NULL;
-        int                     found = 0;
-        struct list_head       *el;
-        int                     rc;
+        struct echo_device *ed     = obd2echo_dev(exp->exp_obd);
+        __u64               cookie = oa->o_handle.cookie;
 
         if ((oa->o_valid & OBD_MD_FLHANDLE) == 0)
                 return -EINVAL;
 
-        spin_lock (&ec->ec_lock);
-
-        list_for_each (el, &exp->exp_ec_data.eced_locks) {
-                ecl = list_entry (el, struct ec_lock, ecl_exp_chain);
-                found = (ecl->ecl_cookie == ulh->cookie);
-                if (found) {
-                        list_del (&ecl->ecl_exp_chain);
-                        break;
-                }
-        }
-
-        spin_unlock (&ec->ec_lock);
-
-        if (!found)
-                return (-ENOENT);
-
-        rc = obd_cancel(ec->ec_exp, ecl->ecl_object->eco_lsm, ecl->ecl_mode,
-                        &ecl->ecl_lock_handle);
-
-        echo_put_object (ecl->ecl_object);
-        OBD_FREE (ecl, sizeof (*ecl));
-
-        return rc;
+        CDEBUG(D_INFO, "Cookie is "LPX64"\n", cookie);
+        return cl_echo_cancel(ed, cookie);
 }
 
 static int
-echo_client_iocontrol(unsigned int cmd, struct obd_export *exp,
-                      int len, void *karg, void *uarg)
+echo_client_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
+                      void *karg, void *uarg)
 {
-        struct obd_device      *obd;
-        struct echo_client_obd *ec;
-        struct ec_object       *eco;
+        struct obd_device      *obd = exp->exp_obd;
+        struct echo_device     *ed = obd2echo_dev(obd);
+        struct echo_client_obd *ec = ed->ed_ec;
+        struct echo_object     *eco;
         struct obd_ioctl_data  *data = karg;
         struct obd_trans_info   dummy_oti;
+        struct lu_env          *env;
         struct oti_req_ack_lock *ack_lock;
         struct obdo            *oa;
+        struct lu_fid           fid;
         int                     rw = OBD_BRW_READ;
         int                     rc = 0;
         int                     i;
@@ -1197,104 +2788,188 @@ echo_client_iocontrol(unsigned int cmd, struct obd_export *exp,
 
         memset(&dummy_oti, 0, sizeof(dummy_oti));
 
-        obd = exp->exp_obd;
-        ec = &obd->u.echo_client;
+        oa = &data->ioc_obdo1;
+        if (!(oa->o_valid & OBD_MD_FLGROUP)) {
+                oa->o_valid |= OBD_MD_FLGROUP;
+                oa->o_seq = FID_SEQ_ECHO;
+        }
+
+        /* This FID is unpacked just for validation at this point */
+        rc = fid_ostid_unpack(&fid, &oa->o_oi, 0);
+        if (rc < 0)
+                RETURN(rc);
+
+        OBD_ALLOC_PTR(env);
+        if (env == NULL)
+                RETURN(-ENOMEM);
+
+        rc = lu_env_init(env, LCT_DT_THREAD);
+        if (rc)
+                GOTO(out, rc = -ENOMEM);
 
         switch (cmd) {
         case OBD_IOC_CREATE:                    /* may create echo object */
-                if (!capable (CAP_SYS_ADMIN))
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
                         GOTO (out, rc = -EPERM);
 
-                rc = echo_create_object (obd, 1, &data->ioc_obdo1,
-                                         data->ioc_pbuf1, data->ioc_plen1,
-                                         &dummy_oti);
+                rc = echo_create_object(env, ed, 1, oa, data->ioc_pbuf1,
+                                        data->ioc_plen1, &dummy_oti);
+                GOTO(out, rc);
+
+        case OBD_IOC_ECHO_MD: {
+                int count;
+                int cmd;
+                char *dir = NULL;
+                int dirlen;
+                __u64 id;
+
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO(out, rc = -EPERM);
+
+                count = data->ioc_count;
+                cmd = data->ioc_command;
+
+                id = data->ioc_obdo2.o_id;
+
+                dirlen = data->ioc_plen1;
+                OBD_ALLOC(dir, dirlen + 1);
+                if (dir == NULL)
+                        GOTO(out, rc = -ENOMEM);
+
+                if (cfs_copy_from_user(dir, data->ioc_pbuf1, dirlen)) {
+                        OBD_FREE(dir, data->ioc_plen1 + 1);
+                        GOTO(out, rc = -EFAULT);
+                }
+
+                rc = echo_md_handler(ed, cmd, dir, dirlen, id, count, data);
+                OBD_FREE(dir, dirlen + 1);
                 GOTO(out, rc);
+        }
+        case OBD_IOC_ECHO_ALLOC_SEQ: {
+                struct lu_env   *cl_env;
+                int              refcheck;
+                __u64            seq;
+                int              max_count;
+
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO(out, rc = -EPERM);
+
+                cl_env = cl_env_get(&refcheck);
+                if (IS_ERR(cl_env))
+                        GOTO(out, rc = PTR_ERR(cl_env));
+
+                rc = lu_env_refill_by_tags(cl_env, ECHO_MD_CTX_TAG,
+                                            ECHO_MD_SES_TAG);
+                if (rc != 0) {
+                        cl_env_put(cl_env, &refcheck);
+                        GOTO(out, rc);
+                }
+
+                rc = seq_client_get_seq(cl_env, ed->ed_cl_seq, &seq);
+                cl_env_put(cl_env, &refcheck);
+                if (rc < 0) {
+                        CERROR("%s: Can not alloc seq: rc = %d\n",
+                               obd->obd_name, rc);
+                        GOTO(out, rc);
+                }
+
+                if (cfs_copy_to_user(data->ioc_pbuf1, &seq, data->ioc_plen1))
+                        return -EFAULT;
 
+                max_count = LUSTRE_SEQ_MAX_WIDTH;
+                if (cfs_copy_to_user(data->ioc_pbuf2, &max_count,
+                                     data->ioc_plen2))
+                        return -EFAULT;
+                GOTO(out, rc);
+        }
         case OBD_IOC_DESTROY:
-                if (!capable (CAP_SYS_ADMIN))
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
                         GOTO (out, rc = -EPERM);
 
-                rc = echo_get_object (&eco, obd, &data->ioc_obdo1);
+                rc = echo_get_object(&eco, ed, oa);
                 if (rc == 0) {
-                        oa = &data->ioc_obdo1;
-                        oa->o_gr = 2;
-                        oa->o_valid |= OBD_MD_FLGROUP;
-                        rc = obd_destroy(ec->ec_exp, oa, eco->eco_lsm, 
-                                         &dummy_oti);
+                        rc = obd_destroy(env, ec->ec_exp, oa, eco->eo_lsm,
+                                         &dummy_oti, NULL, NULL);
                         if (rc == 0)
-                                eco->eco_deleted = 1;
+                                eco->eo_deleted = 1;
                         echo_put_object(eco);
                 }
                 GOTO(out, rc);
 
         case OBD_IOC_GETATTR:
-                rc = echo_get_object (&eco, obd, &data->ioc_obdo1);
+                rc = echo_get_object(&eco, ed, oa);
                 if (rc == 0) {
-                        rc = obd_getattr(ec->ec_exp, &data->ioc_obdo1,
-                                         eco->eco_lsm);
+                        struct obd_info oinfo = { { { 0 } } };
+                        oinfo.oi_md = eco->eo_lsm;
+                        oinfo.oi_oa = oa;
+                        rc = obd_getattr(env, ec->ec_exp, &oinfo);
                         echo_put_object(eco);
                 }
                 GOTO(out, rc);
 
         case OBD_IOC_SETATTR:
-                if (!capable (CAP_SYS_ADMIN))
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
                         GOTO (out, rc = -EPERM);
 
-                rc = echo_get_object (&eco, obd, &data->ioc_obdo1);
+                rc = echo_get_object(&eco, ed, oa);
                 if (rc == 0) {
-                        rc = obd_setattr(ec->ec_exp, &data->ioc_obdo1,
-                                         eco->eco_lsm, NULL);
+                        struct obd_info oinfo = { { { 0 } } };
+                        oinfo.oi_oa = oa;
+                        oinfo.oi_md = eco->eo_lsm;
+
+                        rc = obd_setattr(env, ec->ec_exp, &oinfo, NULL);
                         echo_put_object(eco);
                 }
                 GOTO(out, rc);
 
         case OBD_IOC_BRW_WRITE:
-                if (!capable (CAP_SYS_ADMIN))
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
                         GOTO (out, rc = -EPERM);
 
                 rw = OBD_BRW_WRITE;
                 /* fall through */
         case OBD_IOC_BRW_READ:
-                rc = echo_client_brw_ioctl(rw, exp, data);
+               rc = echo_client_brw_ioctl(env, rw, exp, data, &dummy_oti);
                 GOTO(out, rc);
 
         case ECHO_IOC_GET_STRIPE:
-                rc = echo_get_object(&eco, obd, &data->ioc_obdo1);
+                rc = echo_get_object(&eco, ed, oa);
                 if (rc == 0) {
-                        rc = echo_copyout_lsm(eco->eco_lsm, data->ioc_pbuf1,
+                        rc = echo_copyout_lsm(eco->eo_lsm, data->ioc_pbuf1,
                                               data->ioc_plen1);
                         echo_put_object(eco);
                 }
                 GOTO(out, rc);
 
         case ECHO_IOC_SET_STRIPE:
-                if (!capable (CAP_SYS_ADMIN))
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
                         GOTO (out, rc = -EPERM);
 
                 if (data->ioc_pbuf1 == NULL) {  /* unset */
-                        rc = echo_get_object(&eco, obd, &data->ioc_obdo1);
+                        rc = echo_get_object(&eco, ed, oa);
                         if (rc == 0) {
-                                eco->eco_deleted = 1;
+                                eco->eo_deleted = 1;
                                 echo_put_object(eco);
                         }
                 } else {
-                        rc = echo_create_object(obd, 0, &data->ioc_obdo1,
+                        rc = echo_create_object(env, ed, 0, oa,
                                                 data->ioc_pbuf1,
                                                 data->ioc_plen1, &dummy_oti);
                 }
                 GOTO (out, rc);
 
         case ECHO_IOC_ENQUEUE:
-                if (!capable (CAP_SYS_ADMIN))
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
                         GOTO (out, rc = -EPERM);
 
-                rc = echo_client_enqueue(exp, &data->ioc_obdo1,
+                rc = echo_client_enqueue(exp, oa,
                                          data->ioc_conn1, /* lock mode */
-                                   data->ioc_offset, data->ioc_count);/*extent*/
+                                         data->ioc_offset,
+                                         data->ioc_count);/*extent*/
                 GOTO (out, rc);
 
         case ECHO_IOC_CANCEL:
-                rc = echo_client_cancel(exp, &data->ioc_obdo1);
+                rc = echo_client_cancel(exp, oa);
                 GOTO (out, rc);
 
         default:
@@ -1303,10 +2978,12 @@ echo_client_iocontrol(unsigned int cmd, struct obd_export *exp,
         }
 
         EXIT;
- out:
+out:
+        lu_env_fini(env);
+        OBD_FREE_PTR(env);
 
         /* XXX this should be in a helper also called by target_send_reply */
-        for (ack_lock = dummy_oti.oti_ack_locks, i = 0; i < 4; 
+        for (ack_lock = dummy_oti.oti_ack_locks, i = 0; i < 4;
              i++, ack_lock++) {
                 if (!ack_lock->mode)
                         break;
@@ -1316,109 +2993,141 @@ echo_client_iocontrol(unsigned int cmd, struct obd_export *exp,
         return rc;
 }
 
-static int
-echo_client_setup(struct obd_device *obddev, obd_count len, void *buf)
+static int echo_client_setup(const struct lu_env *env,
+                             struct obd_device *obddev, struct lustre_cfg *lcfg)
 {
-        struct lustre_cfg* lcfg = buf;
         struct echo_client_obd *ec = &obddev->u.echo_client;
         struct obd_device *tgt;
-        struct lustre_handle conn = {0, };
         struct obd_uuid echo_uuid = { "ECHO_UUID" };
+        struct obd_connect_data *ocd = NULL;
         int rc;
         ENTRY;
 
-        if (lcfg->lcfg_inllen1 < 1) {
+        if (lcfg->lcfg_bufcount < 2 || LUSTRE_CFG_BUFLEN(lcfg, 1) < 1) {
                 CERROR("requires a TARGET OBD name\n");
                 RETURN(-EINVAL);
         }
 
-        tgt = class_name2obd(lcfg->lcfg_inlbuf1);
+        tgt = class_name2obd(lustre_cfg_string(lcfg, 1));
         if (!tgt || !tgt->obd_attached || !tgt->obd_set_up) {
                 CERROR("device not attached or not set up (%s)\n",
-                       lcfg->lcfg_inlbuf1);
+                       lustre_cfg_string(lcfg, 1));
                 RETURN(-EINVAL);
         }
 
-        spin_lock_init (&ec->ec_lock);
-        INIT_LIST_HEAD (&ec->ec_objects);
+       spin_lock_init(&ec->ec_lock);
+        CFS_INIT_LIST_HEAD (&ec->ec_objects);
+        CFS_INIT_LIST_HEAD (&ec->ec_locks);
         ec->ec_unique = 0;
+        ec->ec_nstripes = 0;
 
-        rc = obd_connect(&conn, tgt, &echo_uuid);
-        if (rc) {
-                CERROR("fail to connect to device %s\n", lcfg->lcfg_inlbuf1);
+        if (!strcmp(tgt->obd_type->typ_name, LUSTRE_MDT_NAME)) {
+                lu_context_tags_update(ECHO_MD_CTX_TAG);
+                lu_session_tags_update(ECHO_MD_SES_TAG);
+                RETURN(0);
+        }
+
+        OBD_ALLOC(ocd, sizeof(*ocd));
+        if (ocd == NULL) {
+                CERROR("Can't alloc ocd connecting to %s\n",
+                       lustre_cfg_string(lcfg, 1));
+                return -ENOMEM;
+        }
+
+        ocd->ocd_connect_flags = OBD_CONNECT_VERSION | OBD_CONNECT_REQPORTAL |
+                                 OBD_CONNECT_GRANT | OBD_CONNECT_FULL20 |
+                                OBD_CONNECT_64BITHASH | OBD_CONNECT_LVB_TYPE;
+        ocd->ocd_version = LUSTRE_VERSION_CODE;
+        ocd->ocd_group = FID_SEQ_ECHO;
+
+        rc = obd_connect(env, &ec->ec_exp, tgt, &echo_uuid, ocd, NULL);
+        if (rc == 0) {
+                /* Turn off pinger because it connects to tgt obd directly. */
+               spin_lock(&tgt->obd_dev_lock);
+               cfs_list_del_init(&ec->ec_exp->exp_obd_chain_timed);
+               spin_unlock(&tgt->obd_dev_lock);
+        }
+
+        OBD_FREE(ocd, sizeof(*ocd));
+
+        if (rc != 0) {
+                CERROR("fail to connect to device %s\n",
+                       lustre_cfg_string(lcfg, 1));
                 return (rc);
         }
-        ec->ec_exp = class_conn2export(&conn);
 
         RETURN(rc);
 }
 
-static int echo_client_cleanup(struct obd_device *obddev, int flags)
+static int echo_client_cleanup(struct obd_device *obddev)
 {
-        struct list_head       *el;
-        struct ec_object       *eco;
+        struct echo_device *ed = obd2echo_dev(obddev);
         struct echo_client_obd *ec = &obddev->u.echo_client;
         int rc;
         ENTRY;
 
-        if (!list_empty(&obddev->obd_exports)) {
-                CERROR("still has clients!\n");
-                RETURN(-EBUSY);
-        }
+        /*Do nothing for Metadata echo client*/
+        if (ed == NULL )
+                RETURN(0);
 
-        /* XXX assuming sole access */
-        while (!list_empty(&ec->ec_objects)) {
-                el = ec->ec_objects.next;
-                eco = list_entry(el, struct ec_object, eco_obj_chain);
+        if (ed->ed_next_ismd) {
+                lu_context_tags_clear(ECHO_MD_CTX_TAG);
+                lu_session_tags_clear(ECHO_MD_SES_TAG);
+                RETURN(0);
+        }
 
-                LASSERT(eco->eco_refcount == 0);
-                eco->eco_refcount = 1;
-                eco->eco_deleted = 1;
-                echo_put_object(eco);
+        if (!cfs_list_empty(&obddev->obd_exports)) {
+                CERROR("still has clients!\n");
+                RETURN(-EBUSY);
         }
 
-        rc = obd_disconnect(ec->ec_exp, 0);
+        LASSERT(cfs_atomic_read(&ec->ec_exp->exp_refcount) > 0);
+        rc = obd_disconnect(ec->ec_exp);
         if (rc != 0)
                 CERROR("fail to disconnect device: %d\n", rc);
 
         RETURN(rc);
 }
 
-static int echo_client_connect(struct lustre_handle *conn,
-                               struct obd_device *src, struct obd_uuid *cluuid)
+static int echo_client_connect(const struct lu_env *env,
+                               struct obd_export **exp,
+                               struct obd_device *src, struct obd_uuid *cluuid,
+                               struct obd_connect_data *data, void *localdata)
 {
-        struct obd_export *exp;
         int                rc;
+        struct lustre_handle conn = { 0 };
 
-        rc = class_connect(conn, src, cluuid);
+        ENTRY;
+        rc = class_connect(&conn, src, cluuid);
         if (rc == 0) {
-                exp = class_conn2export(conn);
-                INIT_LIST_HEAD(&exp->exp_ec_data.eced_locks);
-                class_export_put(exp);
+                *exp = class_conn2export(&conn);
         }
 
         RETURN (rc);
 }
 
-static int echo_client_disconnect(struct obd_export *exp, int flags)
+static int echo_client_disconnect(struct obd_export *exp)
 {
+#if 0
         struct obd_device      *obd;
         struct echo_client_obd *ec;
         struct ec_lock         *ecl;
+#endif
         int                     rc;
         ENTRY;
 
         if (exp == NULL)
                 GOTO(out, rc = -EINVAL);
 
+#if 0
         obd = exp->exp_obd;
         ec = &obd->u.echo_client;
 
         /* no more contention on export's lock list */
-        while (!list_empty (&exp->exp_ec_data.eced_locks)) {
-                ecl = list_entry (exp->exp_ec_data.eced_locks.next,
-                                  struct ec_lock, ecl_exp_chain);
-                list_del (&ecl->ecl_exp_chain);
+        while (!cfs_list_empty (&exp->exp_ec_data.eced_locks)) {
+                ecl = cfs_list_entry (exp->exp_ec_data.eced_locks.next,
+                                      struct ec_lock, ecl_exp_chain);
+                cfs_list_del (&ecl->ecl_exp_chain);
 
                 rc = obd_cancel(ec->ec_exp, ecl->ecl_object->eco_lsm,
                                  ecl->ecl_mode, &ecl->ecl_lock_handle);
@@ -1429,17 +3138,22 @@ static int echo_client_disconnect(struct obd_export *exp, int flags)
                 echo_put_object (ecl->ecl_object);
                 OBD_FREE (ecl, sizeof (*ecl));
         }
+#endif
 
-        rc = class_disconnect(exp, 0);
+        rc = class_disconnect(exp);
         GOTO(out, rc);
  out:
         return rc;
 }
 
-static struct obd_ops echo_obd_ops = {
+static struct obd_ops echo_client_obd_ops = {
         .o_owner       = THIS_MODULE,
+
+#if 0
         .o_setup       = echo_client_setup,
         .o_cleanup     = echo_client_cleanup,
+#endif
+
         .o_iocontrol   = echo_client_iocontrol,
         .o_connect     = echo_client_connect,
         .o_disconnect  = echo_client_disconnect
@@ -1447,14 +3161,82 @@ static struct obd_ops echo_obd_ops = {
 
 int echo_client_init(void)
 {
-        struct lprocfs_static_vars lvars;
+        struct lprocfs_static_vars lvars = { 0 };
+        int rc;
+
+        lprocfs_echo_init_vars(&lvars);
 
-        lprocfs_init_vars(echo, &lvars);
-        return class_register_type(&echo_obd_ops, lvars.module_vars,
-                                   OBD_ECHO_CLIENT_DEVICENAME);
+        rc = lu_kmem_init(echo_caches);
+        if (rc == 0) {
+                rc = class_register_type(&echo_client_obd_ops, NULL,
+                                         lvars.module_vars,
+                                         LUSTRE_ECHO_CLIENT_NAME,
+                                         &echo_device_type);
+                if (rc)
+                        lu_kmem_fini(echo_caches);
+        }
+        return rc;
 }
 
 void echo_client_exit(void)
 {
-        class_unregister_type(OBD_ECHO_CLIENT_DEVICENAME);
+        class_unregister_type(LUSTRE_ECHO_CLIENT_NAME);
+        lu_kmem_fini(echo_caches);
+}
+
+#ifdef __KERNEL__
+static int __init obdecho_init(void)
+{
+        struct lprocfs_static_vars lvars;
+        int rc;
+
+        ENTRY;
+        LCONSOLE_INFO("Echo OBD driver; http://www.lustre.org/\n");
+
+        LASSERT(CFS_PAGE_SIZE % OBD_ECHO_BLOCK_SIZE == 0);
+
+        lprocfs_echo_init_vars(&lvars);
+
+# ifdef HAVE_SERVER_SUPPORT
+        rc = echo_persistent_pages_init();
+        if (rc != 0)
+                goto failed_0;
+
+        rc = class_register_type(&echo_obd_ops, NULL, lvars.module_vars,
+                                 LUSTRE_ECHO_NAME, NULL);
+        if (rc != 0)
+                goto failed_1;
+# endif
+
+        rc = echo_client_init();
+
+# ifdef HAVE_SERVER_SUPPORT
+        if (rc == 0)
+                RETURN(0);
+
+        class_unregister_type(LUSTRE_ECHO_NAME);
+failed_1:
+        echo_persistent_pages_fini();
+failed_0:
+# endif
+        RETURN(rc);
+}
+
+static void /*__exit*/ obdecho_exit(void)
+{
+        echo_client_exit();
+
+# ifdef HAVE_SERVER_SUPPORT
+        class_unregister_type(LUSTRE_ECHO_NAME);
+        echo_persistent_pages_fini();
+# endif
 }
+
+MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
+MODULE_DESCRIPTION("Lustre Testing Echo OBD driver");
+MODULE_LICENSE("GPL");
+
+cfs_module(obdecho, LUSTRE_VERSION_STRING, obdecho_init, obdecho_exit);
+#endif /* __KERNEL__ */
+
+/** @} echo_client */