Whamcloud - gitweb
LU-1067 obdecho: Recheck client env ctx for echo md client.
[fs/lustre-release.git] / lustre / obdecho / echo_client.c
index 4ccc043..5deec15 100644 (file)
 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
  * vim:expandtab:shiftwidth=8:tabstop=8:
  *
- *  Copyright (c) 2001, 2002 Cluster File Systems, Inc.
+ * GPL HEADER START
  *
- *   This file is part of Lustre, http://www.lustre.org.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
- *   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 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 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.
+ * 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).
  *
- *   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.
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011 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 <libcfs/libcfs.h>
+#else
+#include <liblustre.h>
+#endif
+
+#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 "echo_internal.h"
+
+/** \defgroup echo_client Echo Client
+ * @{
+ */
+
+struct echo_device {
+        struct cl_device        ed_cl;
+        struct echo_client_obd *ed_ec;
+
+        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;
+        cfs_mutex_t            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
+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 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;
+        char                    eti_name[20];
+        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.
+ *
+ * @{
+ */
+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)
+                cfs_mutex_lock(&ep->ep_lock);
+        else if (!cfs_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(cfs_mutex_is_locked(&ep->ep_lock));
+        cfs_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 (cfs_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, cfs_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);
+                cfs_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);
+
+        cfs_spin_lock(&ec->ec_lock);
+        cfs_list_add_tail(&eco->eo_obj_chain, &ec->ec_objects);
+        cfs_spin_unlock(&ec->ec_lock);
+
+        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;
+        struct lov_stripe_md *lsm  = eco->eo_lsm;
+        ENTRY;
+
+        LASSERT(cfs_atomic_read(&eco->eo_npages) == 0);
+
+        cfs_spin_lock(&ec->ec_lock);
+        cfs_list_del_init(&eco->eo_obj_chain);
+        cfs_spin_unlock(&ec->ec_lock);
+
+        lu_object_fini(obj);
+        lu_object_header_fini(obj->lo_header);
+
+        if (lsm)
+                obd_free_memmd(ec->ec_exp, &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 echo_session_info *session;
+
+        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);
+        }
+
+        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;
+
+                cfs_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;
+                        }
+                }
+                cfs_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.
+         */
+        cfs_spin_lock(&ec->ec_lock);
+        cfs_list_for_each_entry(eco, &ec->ec_objects, eo_obj_chain)
+                eco->eo_deleted = 1;
+        cfs_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. */
+        cfs_spin_lock(&ec->ec_lock);
+        while (!cfs_list_empty(&ec->ec_objects)) {
+                cfs_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);
+                cfs_spin_lock(&ec->ec_lock);
+        }
+        cfs_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);
+
+        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));
+                cfs_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));
+                        cfs_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;
+                        cfs_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;
+
+        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);
+        cfs_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;
+                }
+        }
+        cfs_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);
+        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,
+                                               CRP_NORMAL, 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, "%llu", id);
+        lname->ln_name = name;
+        lname->ln_namelen = strlen(name);
+}
+
+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;
+        int                      rc;
+
+        ec_child = lu_object_find_at(env, &ed->ed_cl.cd_lu_dev,
+                                     fid, NULL);
+        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);
+
+        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);
+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,
+                             int *max_lmm_size)
+{
+        struct echo_thread_info *info = echo_env_info(env);
+        struct md_device *md = lu2md_dev(ld);
+        int tmp, rc;
+        ENTRY;
+
+        LASSERT(max_lmm_size != NULL);
+        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);
+                *max_lmm_size = 0;
+                RETURN(0);
+        }
+
+        md = lu2md_dev(ld);
+        rc = md->md_ops->mdo_maxsize_get(env, md,
+                                         max_lmm_size, &tmp);
+        if (rc)
+                RETURN(rc);
+
+        if (*max_lmm_size == 0)
+                /* In case xattr is set in echo_setattr_object */
+                *max_lmm_size = sizeof(struct lov_user_md_v3);
+
+        ma->ma_lmm_size = *max_lmm_size;
+        OBD_ALLOC(ma->ma_lmm, ma->ma_lmm_size);
+        if (ma->ma_lmm == NULL)
+                RETURN(-ENOMEM);
+
+        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                      max_lmm_size = 0;
+        int                      i;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+        if (ec_parent == NULL) {
+                lu_object_put(env, ec_parent);
+                RETURN(PTR_ERR(parent));
+        }
+
+        memset(ma, 0, sizeof(*ma));
+        memset(spec, 0, sizeof(*spec));
+        if (stripe_count != 0) {
+                spec->sp_cr_flags |= FMODE_WRITE;
+                rc = echo_set_lmm_size(env, ld, ma, &max_lmm_size);
+                if (rc)
+                        GOTO(out_free, rc);
+                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->sp_cr_flags |= MDS_OPEN_HAS_EA;
+                }
+        }
+
+        ma->ma_attr.la_mode = mode;
+        ma->ma_attr.la_valid = LA_CTIME;
+        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);
+                GOTO(out_free, 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++;
+        }
+
+out_free:
+        if (!strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME) &&
+             max_lmm_size > 0  && ma->ma_lmm != NULL)
+                OBD_FREE(ma->ma_lmm, max_lmm_size);
+
+        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 md_attr          *ma = &info->eti_ma;
+        struct lu_device        *ld = ed->ed_next;
+        struct lov_user_md_v3   *lum = &info->eti_lum;
+        int                      rc = 0;
+        int                      i;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+        if (ec_parent == NULL) {
+                lu_object_put(env, ec_parent);
+                return PTR_ERR(parent);
+        }
+
+        memset(ma, 0, sizeof(*ma));
+        lum->lmm_magic = LOV_USER_MAGIC_V3;
+        lum->lmm_stripe_count = 1;
+        lum->lmm_stripe_offset = -1;
+        lum->lmm_pattern = 0;
+
+        ma->ma_lmm = (struct lov_mds_md *)lum;
+        ma->ma_lmm_size = sizeof(*lum);
+        ma->ma_valid = MA_LOV | MA_HSM;
+        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 getattr object "DFID"\n",
+                       PFID(lu_object_fid(child)));
+                rc = mo_attr_set(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_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                      max_lmm_size;
+        int                      rc = 0;
+        int                      i;
+
+        parent = lu_object_locate(ec_parent->lo_header, ld->ld_type);
+        if (ec_parent == NULL) {
+                lu_object_put(env, ec_parent);
+                return PTR_ERR(parent);
+        }
+
+        memset(ma, 0, sizeof(*ma));
+        rc = echo_set_lmm_size(env, ld, ma, &max_lmm_size);
+        if (rc)
+                GOTO(out_free, rc);
+
+        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;
+
+                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);
+                        GOTO(out_free, rc = -EINVAL);
+                }
+
+                CDEBUG(D_RPCTRACE, "Start getattr object "DFID"\n",
+                       PFID(lu_object_fid(child)));
+                rc = mo_attr_get(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);
+        }
+
+out_free:
+        if (!strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME) &&
+             max_lmm_size > 0 && ma->ma_lmm)
+                OBD_FREE(ma->ma_lmm, max_lmm_size);
+
+        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 (ec_parent == NULL) {
+                lu_object_put(env, ec_parent);
+                return PTR_ERR(parent);
+        }
+
+        /*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;
+
+        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                      max_lmm_size = 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;
+
+        rc = echo_set_lmm_size(env, ld, ma, &max_lmm_size);
+        if (rc)
+                GOTO(out_free, rc);
+
+        /*FIXME: Do not need logcookie for now, and check stripes*/
+        ma->ma_cookie = NULL;
+        ma->ma_cookie_size = 0;
+        ma->ma_need = MA_INODE | MA_LOV;
+        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);
+                GOTO(out_free, rc);
+        }
+
+        /*prepare the requests*/
+        for (i = 0; i < count; i++) {
+                char *tmp_name = info->eti_name;
+
+                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++;
+        }
+
+out_free:
+        if (!strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME) &&
+             max_lmm_size > 0 && ma->ma_lmm)
+                OBD_FREE(ma->ma_lmm, max_lmm_size);
+
+        RETURN(rc);
+}
+
+struct lu_object *echo_resolve_path(const struct lu_env *env,
+                                    struct echo_device *ed, char *path,
+                                    int path_len)
+{
+        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;
+
+        /*Only support MDD layer right now*/
+        LASSERT(!strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME));
+
+        rc = md->md_ops->mdo_root_get(env, md, fid);
+        if (rc) {
+                CERROR("get root error: rc = %d\n", rc);
+                RETURN(ERR_PTR(rc));
+        }
+
+        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);
+        }
+
+        while (1) {
+                struct lu_object *ld_parent;
+                char *e;
+
+                e = strsep(&path, "/");
+                if (e == NULL)
+                        break;
+
+                if (e[0] == 0) {
+                        if (!path || path[0] == '\0')
+                                break;
+                        continue;
+                }
+
+                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);
+}
+
+#define ECHO_MD_CTX_TAG (LCT_REMEMBER | LCT_NOREF | LCT_MD_THREAD)
+#define ECHO_MD_SES_TAG (LCT_SESSION | LCT_REMEMBER | LCT_NOREF)
+
+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 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;
+
+        if (ld == NULL) {
+                CERROR("MD echo client is not being initialized properly\n");
+                RETURN(-EINVAL);
+        }
+
+        if (strcmp(ld->ld_type->ldt_name, LUSTRE_MDD_NAME)) {
+                CERROR("Only support MDD layer right now!\n");
+                RETURN(-EINVAL);
+        }
+
+        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) {
+                cl_env_put(env, &refcheck);
+                RETURN(rc);
+        }
+
+        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));
+                cl_env_put(env, &refcheck);
+                RETURN(PTR_ERR(parent));
+        }
+
+        if (namelen > 0) {
+                OBD_ALLOC(name, namelen + 1);
+                if (name == NULL)
+                        RETURN(-ENOMEM);
+                if (cfs_copy_from_user(name, data->ioc_pbuf2, namelen)) {
+                        OBD_FREE(name, namelen + 1);
+                        RETURN(-EFAULT);
+                }
+        }
+
+        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;
+                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;
+
+                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;
+        }
+        if (name != NULL)
+                OBD_FREE(name, namelen + 1);
+        lu_object_put(env, parent);
+        cl_env_put(env, &refcheck);
+        return rc;
+}
 
-#include <linux/version.h>
-#include <linux/module.h>
-#include <linux/fs.h>
+static int echo_create_object(struct echo_device *ed, int on_target,
+                              struct obdo *oa, void *ulsm, int ulsm_nob,
+                              struct obd_trans_info *oti)
+{
+        struct echo_object     *eco;
+        struct echo_client_obd *ec = ed->ed_ec;
+        struct lov_stripe_md   *lsm = NULL;
+        int                     rc;
+        int                     created = 0;
+        ENTRY;
 
-#define DEBUG_SUBSYSTEM S_ECHO
+        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);
+        }
+
+        rc = obd_alloc_memmd(ec->ec_exp, &lsm);
+        if (rc < 0) {
+                CERROR("Cannot allocate md: rc = %d\n", rc);
+                GOTO(failed, rc);
+        }
+
+        if (ulsm != NULL) {
+                int i, idx;
+
+                rc = echo_copyin_lsm (ed, lsm, ulsm, ulsm_nob);
+                if (rc != 0)
+                        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 = CFS_PAGE_SIZE;
+
+                idx = cfs_rand();
 
-#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>
+                /* 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;
 
-static int echo_iocontrol(unsigned int cmd, struct lustre_handle *obdconn, int len,
-                          void *karg, void *uarg)
+                        lsm->lsm_oinfo[i]->loi_ost_idx =
+                                (idx + i) % ec->ec_nstripes;
+                }
+        }
+
+        /* setup object ID here for !on_target and LOV hint */
+        if (oa->o_valid & OBD_MD_FLID)
+                lsm->lsm_object_id = oa->o_id;
+
+        if (lsm->lsm_object_id == 0)
+                lsm->lsm_object_id = ++last_object_id;
+
+        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(ec->ec_exp, oa, &lsm, oti);
+                if (rc != 0) {
+                        CERROR("Cannot create objects: rc = %d\n", rc);
+                        GOTO(failed, rc);
+                }
+                created = 1;
+        }
+
+        /* See what object ID we were given */
+        oa->o_id = lsm->lsm_object_id;
+        oa->o_valid |= OBD_MD_FLID;
+
+        eco = cl_echo_object_find(ed, &lsm);
+        if (IS_ERR(eco))
+                GOTO(failed, rc = PTR_ERR(eco));
+        cl_echo_object_put(eco);
+
+        CDEBUG(D_INFO, "oa->o_id = %lx\n", (long)oa->o_id);
+        EXIT;
+
+ failed:
+        if (created && rc)
+                obd_destroy(ec->ec_exp, oa, lsm, oti, NULL, NULL);
+        if (lsm)
+                obd_free_memmd(ec->ec_exp, &lsm);
+        if (rc)
+                CERROR("create object failed with: rc = %d\n", rc);
+        return (rc);
+}
+
+static int echo_get_object(struct echo_object **ecop, struct echo_device *ed,
+                           struct obdo *oa)
 {
-        struct obd_device *obd = class_conn2obd(obdconn);
-        struct echo_client_obd *ec = &obd->u.echo_client;
-        struct obd_ioctl_data *data = karg;
-        int rw = OBD_BRW_READ, rc = 0;
-        struct lov_stripe_md *lsm = NULL;
+        struct echo_client_obd *ec  = ed->ed_ec;
+        struct lov_stripe_md   *lsm = NULL;
+        struct echo_object     *eco;
+        int                     rc;
         ENTRY;
 
-        if (obd == NULL) {
-                CERROR("ioctl: No device\n");
-                GOTO(out, rc = -EINVAL);
+        if ((oa->o_valid & OBD_MD_FLID) == 0 ||
+            oa->o_id == 0)  /* disallow use of object id 0 */
+        {
+                CERROR ("No valid oid\n");
+                RETURN(-EINVAL);
         }
 
-        if (data->ioc_inllen1 == sizeof(*lsm)) {
-                lsm = (struct lov_stripe_md *)data->ioc_inlbuf1;
-        } else if (data->ioc_inllen1 != 0) {
-                CERROR("nonzero ioc_inllen1 != sizeof(struct lov_stripe_md)\n");
-                GOTO(out, rc = -EINVAL);
+        rc = obd_alloc_memmd(ec->ec_exp, &lsm);
+        if (rc < 0)
+                RETURN(rc);
+
+        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;
+
+        rc = 0;
+        eco = cl_echo_object_find(ed, &lsm);
+        if (!IS_ERR(eco))
+                *ecop = eco;
+        else
+                rc = PTR_ERR(eco);
+        if (lsm)
+                obd_free_memmd(ec->ec_exp, &lsm);
+        RETURN(rc);
+}
+
+static void echo_put_object(struct echo_object *eco)
+{
+        if (cl_echo_object_put(eco))
+                CERROR("echo client: drop an object failed");
+}
+
+static void
+echo_get_stripe_off_id (struct lov_stripe_md *lsm, obd_off *offp, obd_id *idp)
+{
+        unsigned long stripe_count;
+        unsigned long stripe_size;
+        unsigned long width;
+        unsigned long woffset;
+        int           stripe_index;
+        obd_off       offset;
+
+        if (lsm->lsm_stripe_count <= 1)
+                return;
+
+        offset       = *offp;
+        stripe_size  = lsm->lsm_stripe_size;
+        stripe_count = lsm->lsm_stripe_count;
+
+        /* width = # bytes in all stripes */
+        width = stripe_size * stripe_count;
+
+        /* woffset = offset within a width; offset = whole number of widths */
+        woffset = do_div (offset, width);
+
+        stripe_index = woffset / stripe_size;
+
+        *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,
+                             cfs_page_t *page, int rw, obd_id id,
+                             obd_off offset, obd_off count)
+{
+        char    *addr;
+        obd_off  stripe_off;
+        obd_id   stripe_id;
+        int      delta;
+
+        /* no partial pages on the client */
+        LASSERT(count == CFS_PAGE_SIZE);
+
+        addr = cfs_kmap(page);
+
+        for (delta = 0; delta < CFS_PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
+                if (rw == OBD_BRW_WRITE) {
+                        stripe_off = offset + delta;
+                        stripe_id = id;
+                        echo_get_stripe_off_id(lsm, &stripe_off, &stripe_id);
+                } else {
+                        stripe_off = 0xdeadbeef00c0ffeeULL;
+                        stripe_id = 0xdeadbeef00c0ffeeULL;
+                }
+                block_debug_setup(addr + delta, OBD_ECHO_BLOCK_SIZE,
+                                  stripe_off, stripe_id);
         }
 
-        switch (cmd) {
-        case OBD_IOC_CREATE: {
-                struct lov_stripe_md *tmp_lsm = NULL;
-                rc = obd_create(&ec->conn, &data->ioc_obdo1, &tmp_lsm);
-                if (lsm)
-                        memcpy(lsm, tmp_lsm, sizeof(*tmp_lsm));
+        cfs_kunmap(page);
+}
 
-                GOTO(out, rc);
+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)
+{
+        obd_off stripe_off;
+        obd_id  stripe_id;
+        char   *addr;
+        int     delta;
+        int     rc;
+        int     rc2;
+
+        /* no partial pages on the client */
+        LASSERT(count == CFS_PAGE_SIZE);
+
+        addr = cfs_kmap(page);
+
+        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;
+                }
         }
 
-        case OBD_IOC_GETATTR:
-                rc = obd_getattr(&ec->conn, &data->ioc_obdo1, lsm);
-                GOTO(out, rc);
+        cfs_kunmap(page);
+        return rc;
+}
 
-        case OBD_IOC_SETATTR:
-                rc = obd_setattr(&ec->conn, &data->ioc_obdo1, lsm);
-                GOTO(out, rc);
+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)
+{
+        struct echo_client_obd *ec  = ed->ed_ec;
+        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;
+        int                     brw_flags = 0;
+        ENTRY;
 
-        case OBD_IOC_DESTROY:
-                rc = obd_destroy(&ec->conn, &data->ioc_obdo1, lsm);
-                GOTO(out, rc);
+        verify = ((oa->o_id) != ECHO_PERSISTENT_OBJID &&
+                  (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
+                  (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 
-        case OBD_IOC_OPEN:
-                rc = obd_open(&ec->conn, &data->ioc_obdo1, lsm);
-                GOTO(out, rc);
+        gfp_mask = ((oa->o_id & 2) == 0) ? CFS_ALLOC_STD : CFS_ALLOC_HIGHUSER;
 
-        case OBD_IOC_CLOSE:
-                rc = obd_close(&ec->conn, &data->ioc_obdo1, lsm);
-                GOTO(out, rc);
+        LASSERT(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ);
+        LASSERT(lsm != NULL);
+        LASSERT(lsm->lsm_object_id == oa->o_id);
 
-        case OBD_IOC_BRW_WRITE:
-                rw = OBD_BRW_WRITE;
-        case OBD_IOC_BRW_READ: {
-                struct lov_stripe_md tmp_lsm;
-                struct obd_brw_set *set;
-                obd_count pages = 0;
-                struct brw_page *pga, *pgp;
-                __u64 off, id = data->ioc_obdo1.o_id;
-                int gfp_mask = (id & 1) ? GFP_HIGHUSER : GFP_KERNEL;
-                int j, verify = (id != 0);
-
-                if (lsm && lsm->lsm_object_id != id) {
-                        CERROR("LSM object ID ("LPU64") != id ("LPU64")\n",
-                               lsm->lsm_object_id, id);
-                        GOTO(out, rc = -EINVAL);
+        if (count <= 0 ||
+            (count & (~CFS_PAGE_MASK)) != 0)
+                RETURN(-EINVAL);
+
+        /* XXX think again with misaligned I/O */
+        npages = count >> CFS_PAGE_SHIFT;
+
+        if (rw == OBD_BRW_WRITE)
+                brw_flags = OBD_BRW_ASYNC;
+
+        OBD_ALLOC(pga, npages * sizeof(*pga));
+        if (pga == NULL)
+                RETURN(-ENOMEM);
+
+        OBD_ALLOC(pages, npages * sizeof(*pages));
+        if (pages == NULL) {
+                OBD_FREE(pga, npages * sizeof(*pga));
+                RETURN(-ENOMEM);
+        }
+
+        for (i = 0, pgp = pga, off = offset;
+             i < npages;
+             i++, pgp++, off += CFS_PAGE_SIZE) {
+
+                LASSERT (pgp->pg == NULL);      /* for cleanup */
+
+                rc = -ENOMEM;
+                OBD_PAGE_ALLOC(pgp->pg, gfp_mask);
+                if (pgp->pg == NULL)
+                        goto out;
+
+                pages[i] = pgp->pg;
+                pgp->count = CFS_PAGE_SIZE;
+                pgp->off = off;
+                pgp->flag = brw_flags;
+
+                if (verify)
+                        echo_client_page_debug_setup(lsm, pgp->pg, rw,
+                                                     oa->o_id, off, pgp->count);
+        }
+
+        if (ed->ed_next == NULL) {
+                struct obd_info oinfo = { { { 0 } } };
+                oinfo.oi_oa = oa;
+                oinfo.oi_md = lsm;
+                rc = obd_brw(rw, ec->ec_exp, &oinfo, npages, pga, oti);
+        } else
+                rc = cl_echo_object_brw(eco, rw, offset, pages, npages, async);
+
+ 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;
                 }
+                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 echo_object *eco,
+                                   obd_off offset, obd_size count,
+                                   obd_size batch, struct obd_trans_info *oti)
+{
+        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;
+        ENTRY;
+
+        if (count <= 0 || (count & (~CFS_PAGE_MASK)) != 0 ||
+            (lsm != NULL && lsm->lsm_object_id != oa->o_id))
+                RETURN(-EINVAL);
+
+        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));
 
-                if (!lsm) {
-                        memset(&tmp_lsm, 0, sizeof(tmp_lsm));
-                        lsm = &tmp_lsm;
-                        lsm->lsm_object_id = id;
+        if (lnb == NULL || rnb == NULL)
+                GOTO(out, ret = -ENOMEM);
+
+        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 += CFS_PAGE_SIZE) {
+                        rnb[i].offset = off;
+                        rnb[i].len = CFS_PAGE_SIZE;
                 }
 
-                if (data->ioc_count < 0) {
-                        CERROR("invalid buffer size: "LPD64"\n",
-                               data->ioc_count);
-                        GOTO(out, rc = -EINVAL);
+                ioo.ioo_bufcnt = npages;
+                oti->oti_transno = 0;
+
+                lpages = npages;
+                ret = obd_preprw(rw, exp, oa, 1, &ioo, rnb, &lpages, lnb, oti,
+                                 NULL);
+                if (ret != 0)
+                        GOTO(out, ret);
+                LASSERT(lpages == npages);
+
+                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 ||
+                            (oa->o_valid & OBD_MD_FLFLAGS) == 0 ||
+                            (oa->o_flags & OBD_FL_DEBUG_CHECK) == 0)
+                                continue;
+
+                        if (rw == OBD_BRW_WRITE)
+                                echo_client_page_debug_setup(lsm, page, rw,
+                                                             oa->o_id,
+                                                             rnb[i].offset,
+                                                             rnb[i].len);
+                        else
+                                echo_client_page_debug_check(lsm, page,
+                                                             oa->o_id,
+                                                             rnb[i].offset,
+                                                             rnb[i].len);
                 }
 
-                set = obd_brw_set_new();
-                if (set == NULL)
+                ret = obd_commitrw(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:
+        if (lnb)
+                OBD_FREE(lnb, npages * sizeof(struct niobuf_local));
+        if (rnb)
+                OBD_FREE(rnb, npages * sizeof(struct niobuf_remote));
+        RETURN(ret);
+}
+
+static int echo_client_brw_ioctl(int rw, struct obd_export *exp,
+                                 struct obd_ioctl_data *data)
+{
+        struct obd_device *obd = class_exp2obd(exp);
+        struct echo_device *ed = obd2echo_dev(obd);
+        struct echo_client_obd *ec = ed->ed_ec;
+        struct obd_trans_info dummy_oti = { 0 };
+        struct obdo *oa = &data->ioc_obdo1;
+        struct echo_object *eco;
+        int rc;
+        int async = 1;
+        ENTRY;
+
+        LASSERT(oa->o_valid & OBD_MD_FLGROUP);
+
+        rc = echo_get_object(&eco, ed, oa);
+        if (rc)
+                RETURN(rc);
+
+        oa->o_valid &= ~OBD_MD_FLHANDLE;
+
+        switch((long)data->ioc_pbuf1) {
+        case 1:
+                async = 0;
+                /* fall through */
+        case 2:
+                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, oa,
+                                            eco, data->ioc_offset,
+                                            data->ioc_count, data->ioc_plen1,
+                                            &dummy_oti);
+                break;
+        default:
+                rc = -EINVAL;
+        }
+        echo_put_object(eco);
+        RETURN(rc);
+}
+
+static int
+echo_client_enqueue(struct obd_export *exp, struct obdo *oa,
+                    int mode, obd_off offset, obd_size nob)
+{
+        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 (ed->ed_next == NULL)
+                RETURN(-EOPNOTSUPP);
+
+        if (!(mode == LCK_PR || mode == LCK_PW))
+                RETURN(-EINVAL);
+
+        if ((offset & (~CFS_PAGE_MASK)) != 0 ||
+            (nob & (~CFS_PAGE_MASK)) != 0)
+                RETURN(-EINVAL);
+
+        rc = echo_get_object (&eco, ed, oa);
+        if (rc != 0)
+                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 echo_device *ed     = obd2echo_dev(exp->exp_obd);
+        __u64               cookie = oa->o_handle.cookie;
+
+        if ((oa->o_valid & OBD_MD_FLHANDLE) == 0)
+                return -EINVAL;
+
+        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)
+{
+        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 oti_req_ack_lock *ack_lock;
+        struct obdo            *oa;
+        struct lu_fid           fid;
+        int                     rw = OBD_BRW_READ;
+        int                     rc = 0;
+        int                     i;
+        ENTRY;
+
+#ifndef HAVE_UNLOCKED_IOCTL
+        cfs_unlock_kernel();
+#endif
+
+        memset(&dummy_oti, 0, sizeof(dummy_oti));
+
+        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);
+
+        switch (cmd) {
+        case OBD_IOC_CREATE:                    /* may create echo object */
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO (out, rc = -EPERM);
+
+                rc = echo_create_object (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);
 
-                pages = data->ioc_count / PAGE_SIZE;
-                off = data->ioc_offset;
+                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   *env;
+                int              refcheck;
+                __u64            seq;
+                int              max_count;
 
-                CDEBUG(D_INODE, "BRW %s with %d pages @ "LPX64"\n",
-                       rw == OBD_BRW_READ ? "read" : "write", pages, off);
-                OBD_ALLOC(pga, pages * sizeof(*pga));
-                if (!pga) {
-                        CERROR("no memory for %d BRW per-page data\n", pages);
-                        GOTO(brw_free, rc = -ENOMEM);
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO(out, rc = -EPERM);
+
+                env = cl_env_get(&refcheck);
+                if (IS_ERR(env))
+                        GOTO(out, rc = PTR_ERR(env));
+
+                rc = lu_env_refill_by_tags(env, ECHO_MD_CTX_TAG,
+                                            ECHO_MD_SES_TAG);
+                if (rc != 0) {
+                        cl_env_put(env, &refcheck);
+                        GOTO(out, rc);
                 }
 
-                for (j = 0, pgp = pga; j < pages; j++, off += PAGE_SIZE, pgp++){
-                        pgp->pg = alloc_pages(gfp_mask, 0);
-                        if (!pgp->pg) {
-                                CERROR("no memory for brw pages\n");
-                                GOTO(brw_cleanup, rc = -ENOMEM);
-                        }
-                        pgp->count = PAGE_SIZE;
-                        pgp->off = off;
-                        pgp->flag = 0;
-
-                        if (verify) {
-                                void *addr = kmap(pgp->pg);
-
-                                if (rw == OBD_BRW_WRITE)
-                                        page_debug_setup(addr, pgp->count,
-                                                         pgp->off, id);
-                                else
-                                        page_debug_setup(addr, pgp->count,
-                                                         0xdeadbeef00c0ffee,
-                                                         0xdeadbeef00c0ffee);
-                                kunmap(pgp->pg);
-                        }
+                rc = seq_client_get_seq(env, ed->ed_cl_seq, &seq);
+                cl_env_put(env, &refcheck);
+                if (rc < 0) {
+                        CERROR("%s: Can not alloc seq: rc = %d\n",
+                               obd->obd_name, rc);
+                        GOTO(out, rc);
                 }
 
-                set->brw_callback = ll_brw_sync_wait;
-                rc = obd_brw(rw, &ec->conn, lsm, j, pga, set);
-                if (rc)
-                        CERROR("test_brw: error from obd_brw: rc = %d\n", rc);
-                else {
-                        rc = ll_brw_sync_wait(set, CB_PHASE_START);
-                        if (rc)
-                                CERROR("test_brw: error from callback: rc = "
-                                       "%d\n", 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 (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO (out, rc = -EPERM);
+
+                rc = echo_get_object (&eco, ed, oa);
+                if (rc == 0) {
+                        rc = obd_destroy(ec->ec_exp, oa, eco->eo_lsm,
+                                         &dummy_oti, NULL, NULL);
+                        if (rc == 0)
+                                eco->eo_deleted = 1;
+                        echo_put_object(eco);
                 }
-                EXIT;
-        brw_cleanup:
-                for (j = 0, pgp = pga; j < pages; j++, pgp++) {
-                        if (pgp->pg == NULL)
-                                continue;
+                GOTO(out, rc);
+
+        case OBD_IOC_GETATTR:
+                rc = echo_get_object (&eco, ed, oa);
+                if (rc == 0) {
+                        struct obd_info oinfo = { { { 0 } } };
+                        oinfo.oi_md = eco->eo_lsm;
+                        oinfo.oi_oa = oa;
+                        rc = obd_getattr(ec->ec_exp, &oinfo);
+                        echo_put_object(eco);
+                }
+                GOTO(out, rc);
+
+        case OBD_IOC_SETATTR:
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO (out, rc = -EPERM);
 
-                        if (verify && !rc) {
-                                void *addr = kmap(pgp->pg);
+                rc = echo_get_object (&eco, ed, oa);
+                if (rc == 0) {
+                        struct obd_info oinfo = { { { 0 } } };
+                        oinfo.oi_oa = oa;
+                        oinfo.oi_md = eco->eo_lsm;
 
-                                rc = page_debug_check("test_brw", addr,
-                                                       PAGE_SIZE, pgp->off, id);
-                                kunmap(pgp->pg);
-                        }
-                        __free_pages(pgp->pg, 0);
+                        rc = obd_setattr(ec->ec_exp, &oinfo, NULL);
+                        echo_put_object(eco);
                 }
-        brw_free:
-                obd_brw_set_free(set);
-                OBD_FREE(pga, pages * sizeof(*pga));
                 GOTO(out, rc);
-        }
+
+        case OBD_IOC_BRW_WRITE:
+                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);
+                GOTO(out, rc);
+
+        case ECHO_IOC_GET_STRIPE:
+                rc = echo_get_object(&eco, ed, oa);
+                if (rc == 0) {
+                        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 (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO (out, rc = -EPERM);
+
+                if (data->ioc_pbuf1 == NULL) {  /* unset */
+                        rc = echo_get_object(&eco, ed, oa);
+                        if (rc == 0) {
+                                eco->eo_deleted = 1;
+                                echo_put_object(eco);
+                        }
+                } else {
+                        rc = echo_create_object(ed, 0, oa,
+                                                data->ioc_pbuf1,
+                                                data->ioc_plen1, &dummy_oti);
+                }
+                GOTO (out, rc);
+
+        case ECHO_IOC_ENQUEUE:
+                if (!cfs_capable(CFS_CAP_SYS_ADMIN))
+                        GOTO (out, rc = -EPERM);
+
+                rc = echo_client_enqueue(exp, oa,
+                                         data->ioc_conn1, /* lock mode */
+                                         data->ioc_offset,
+                                         data->ioc_count);/*extent*/
+                GOTO (out, rc);
+
+        case ECHO_IOC_CANCEL:
+                rc = echo_client_cancel(exp, oa);
+                GOTO (out, rc);
+
         default:
-                CERROR ("echo_ioctl(): unrecognised ioctl %#lx\n", cmd);
+                CERROR ("echo_ioctl(): unrecognised ioctl %#x\n", cmd);
                 GOTO (out, rc = -ENOTTY);
         }
 
+        EXIT;
  out:
-        RETURN(rc);
+
+        /* 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;
+             i++, ack_lock++) {
+                if (!ack_lock->mode)
+                        break;
+                ldlm_lock_decref(&ack_lock->lock, ack_lock->mode);
+        }
+
+#ifndef HAVE_UNLOCKED_IOCTL
+        cfs_lock_kernel();
+#endif
+
+        return rc;
 }
 
-static int echo_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 obd_ioctl_data* data = buf;
         struct echo_client_obd *ec = &obddev->u.echo_client;
         struct obd_device *tgt;
+        struct obd_uuid echo_uuid = { "ECHO_UUID" };
+        struct obd_connect_data *ocd = NULL;
         int rc;
         ENTRY;
 
-        if (data->ioc_inllen1 < 1) {
-                CERROR("requires a TARGET OBD UUID\n");
+        if (lcfg->lcfg_bufcount < 2 || LUSTRE_CFG_BUFLEN(lcfg, 1) < 1) {
+                CERROR("requires a TARGET OBD name\n");
                 RETURN(-EINVAL);
         }
-        if (data->ioc_inllen1 > 37) {
-                CERROR("OBD UUID must be less than 38 characters\n");
+
+        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",
+                       lustre_cfg_string(lcfg, 1));
                 RETURN(-EINVAL);
         }
 
-        MOD_INC_USE_COUNT;
-        tgt = class_uuid2obd(data->ioc_inlbuf1);
-        if (!tgt || !(tgt->obd_flags & OBD_ATTACHED) ||
-            !(tgt->obd_flags & OBD_SET_UP)) {
-                CERROR("device not attached or not set up (%d)\n",
-                       data->ioc_dev);
-                GOTO(error_dec, rc = -EINVAL);
+        cfs_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;
+
+        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;
         }
 
-        rc = obd_connect(&ec->conn, tgt, NULL, NULL, NULL);
-        if (rc) {
-                CERROR("fail to connect to device %d\n", data->ioc_dev);
-                GOTO(error_dec, rc = -EINVAL);
+        ocd->ocd_connect_flags = OBD_CONNECT_VERSION | OBD_CONNECT_REQPORTAL |
+                                 OBD_CONNECT_GRANT | OBD_CONNECT_FULL20 |
+                                 OBD_CONNECT_64BITHASH;
+        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. */
+                cfs_spin_lock(&tgt->obd_dev_lock);
+                cfs_list_del_init(&ec->ec_exp->exp_obd_chain_timed);
+                cfs_spin_unlock(&tgt->obd_dev_lock);
         }
-        RETURN(rc);
-error_dec:
-        MOD_DEC_USE_COUNT;
+
+        OBD_FREE(ocd, sizeof(*ocd));
+
+        if (rc != 0) {
+                CERROR("fail to connect to device %s\n",
+                       lustre_cfg_string(lcfg, 1));
+                return (rc);
+        }
+
         RETURN(rc);
 }
 
-static int echo_cleanup(struct obd_device * obddev)
+static int echo_client_cleanup(struct obd_device *obddev)
 {
+        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)) {
+        /*Do nothing for Metadata echo client*/
+        if (ed == NULL )
+                RETURN(0);
+
+        if (ed->ed_next_ismd) {
+                lu_context_tags_clear(ECHO_MD_CTX_TAG);
+                lu_session_tags_clear(ECHO_MD_SES_TAG);
+                RETURN(0);
+        }
+
+        if (!cfs_list_empty(&obddev->obd_exports)) {
                 CERROR("still has clients!\n");
                 RETURN(-EBUSY);
         }
 
-        rc = obd_disconnect(&ec->conn);
-        if (rc) {
+        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(-EINVAL);
+
+        RETURN(rc);
+}
+
+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)
+{
+        int                rc;
+        struct lustre_handle conn = { 0 };
+
+        ENTRY;
+        rc = class_connect(&conn, src, cluuid);
+        if (rc == 0) {
+                *exp = class_conn2export(&conn);
         }
 
-        MOD_DEC_USE_COUNT;
-        RETURN(0);
+        RETURN (rc);
 }
 
-static int echo_connect(struct lustre_handle *conn, struct obd_device *src,
-                        obd_uuid_t cluuid, struct recovd_obd *recovd,
-                        ptlrpc_recovery_cb_t recover)
+static int echo_client_disconnect(struct obd_export *exp)
 {
-        return class_connect(conn, src, cluuid);
+#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 (!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);
+
+                CDEBUG (D_INFO, "Cancel lock on object "LPX64" on disconnect "
+                        "(%d)\n", ecl->ecl_object->eco_id, rc);
+
+                echo_put_object (ecl->ecl_object);
+                OBD_FREE (ecl, sizeof (*ecl));
+        }
+#endif
+
+        rc = class_disconnect(exp);
+        GOTO(out, rc);
+ out:
+        return rc;
 }
 
 static struct obd_ops echo_obd_ops = {
-        o_setup:       echo_setup,
-        o_cleanup:     echo_cleanup,
-        o_iocontrol:   echo_iocontrol,
-        o_connect:     echo_connect,
-        o_disconnect:  class_disconnect
+        .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
 };
 
 int echo_client_init(void)
 {
-        extern struct lprocfs_vars status_class_var[];
+        struct lprocfs_static_vars lvars = { 0 };
+        int rc;
 
-        return class_register_type(&echo_obd_ops, status_class_var,
-                                   OBD_ECHO_CLIENT_DEVICENAME);
+        lprocfs_echo_init_vars(&lvars);
+
+        rc = lu_kmem_init(echo_caches);
+        if (rc == 0) {
+                rc = class_register_type(&echo_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_cleanup(void)
+void echo_client_exit(void)
 {
-        class_unregister_type(OBD_ECHO_CLIENT_DEVICENAME);
+        class_unregister_type(LUSTRE_ECHO_CLIENT_NAME);
+        lu_kmem_fini(echo_caches);
 }
+
+/** @} echo_client */