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LU-9753 ofd: 64-bits diff variable to avoid overflow
[fs/lustre-release.git] / lustre / ofd / ofd_dev.c
index f6dbfeb..2476f9e 100644 (file)
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2012, 2013, Intel Corporation.
+ * Copyright (c) 2012, 2016, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
- * lustre/ofd/ofd.c
+ * lustre/ofd/ofd_dev.c
+ *
+ * This file contains OSD API methods for OBD Filter Device (OFD),
+ * request handlers and supplemental functions to set OFD up and clean it up.
+ *
+ * Author: Alex Zhuravlev <alexey.zhuravlev@intel.com>
+ * Author: Mike Pershin <mike.pershin@intel.com>
+ * Author: Johann Lombardi <johann.lombardi@intel.com>
+ */
+/*
+ * The OBD Filter Device (OFD) module belongs to the Object Storage
+ * Server stack and connects the RPC oriented Unified Target (TGT)
+ * layer (see lustre/include/lu_target.h) to the storage oriented OSD
+ * layer (see Documentation/osd-api.txt).
+ *
+ *     TGT
+ *      |      DT and OBD APIs
+ *     OFD
+ *      |      DT API
+ *     OSD
+ *
+ * OFD implements the LU and OBD device APIs and is responsible for:
+ *
+ * - Handling client requests (create, destroy, bulk IO, setattr,
+ *   get_info, set_info, statfs) for the objects belonging to the OST
+ *   (together with TGT).
  *
- * Author: Alex Zhuravlev <bzzz@whamcloud.com>
- * Author: Mike Pershin <tappro@whamcloud.com>
- * Author: Johann Lombardi <johann@whamcloud.com>
+ * - Providing grant space management which allows clients to reserve
+ *   disk space for data writeback. OFD tracks grants on global and
+ *   per client levels.
+ *
+ * - Handling object precreation requests from MDTs.
+ *
+ * - Operating the LDLM service that allows clients to maintain object
+ *   data cache coherence.
  */
 
 #define DEBUG_SUBSYSTEM S_FILTER
 
 #include <obd_class.h>
-#include <lustre_param.h>
+#include <obd_cksum.h>
+#include <uapi/linux/lustre_param.h>
 #include <lustre_fid.h>
 #include <lustre_lfsck.h>
 #include <lustre/lustre_idl.h>
 #include <lustre_dlm.h>
 #include <lustre_quota.h>
+#include <lustre_nodemap.h>
+#include <lustre_log.h>
 
 #include "ofd_internal.h"
 
@@ -66,6 +95,20 @@ static struct lu_kmem_descr ofd_caches[] = {
        }
 };
 
+/**
+ * Connect OFD to the next device in the stack.
+ *
+ * This function is used for device stack configuration and links OFD
+ * device with bottom OSD device.
+ *
+ * \param[in]  env     execution environment
+ * \param[in]  m       OFD device
+ * \param[in]  next    name of next device in the stack
+ * \param[out] exp     export to return
+ *
+ * \retval             0 and export in \a exp if successful
+ * \retval             negative value on error
+ */
 static int ofd_connect_to_next(const struct lu_env *env, struct ofd_device *m,
                               const char *next, struct obd_export **exp)
 {
@@ -107,6 +150,18 @@ out:
        RETURN(rc);
 }
 
+/**
+ * Initialize stack of devices.
+ *
+ * This function initializes OFD-OSD device stack to serve OST requests
+ *
+ * \param[in] env      execution environment
+ * \param[in] m                OFD device
+ * \param[in] cfg      Lustre config for this server
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_stack_init(const struct lu_env *env,
                          struct ofd_device *m, struct lustre_cfg *cfg)
 {
@@ -114,6 +169,7 @@ static int ofd_stack_init(const struct lu_env *env,
        struct lu_device        *d;
        struct ofd_thread_info  *info = ofd_info(env);
        struct lustre_mount_info *lmi;
+       struct lustre_mount_data *lmd;
        int                      rc;
        char                    *osdname;
 
@@ -125,6 +181,10 @@ static int ofd_stack_init(const struct lu_env *env,
                RETURN(-ENODEV);
        }
 
+       lmd = s2lsi(lmi->lmi_sb)->lsi_lmd;
+       if (lmd != NULL && lmd->lmd_flags & LMD_FLG_SKIP_LFSCK)
+               m->ofd_skip_lfsck = 1;
+
        /* find bottom osd */
        OBD_ALLOC(osdname, MTI_NAME_MAXLEN);
        if (osdname == NULL)
@@ -146,6 +206,19 @@ static int ofd_stack_init(const struct lu_env *env,
        RETURN(rc);
 }
 
+/**
+ * Finalize the device stack OFD-OSD.
+ *
+ * This function cleans OFD-OSD device stack and
+ * disconnects OFD from the OSD.
+ *
+ * \param[in] env      execution environment
+ * \param[in] m                OFD device
+ * \param[in] top      top device of stack
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static void ofd_stack_fini(const struct lu_env *env, struct ofd_device *m,
                           struct lu_device *top)
 {
@@ -164,15 +237,14 @@ static void ofd_stack_fini(const struct lu_env *env, struct ofd_device *m,
        if (obd->obd_fail)
                strcat(flags, "A");
        lustre_cfg_bufs_set_string(&bufs, 1, flags);
-       lcfg = lustre_cfg_new(LCFG_CLEANUP, &bufs);
-       if (!lcfg) {
-               CERROR("Cannot alloc lcfg!\n");
+       OBD_ALLOC(lcfg, lustre_cfg_len(bufs.lcfg_bufcount, bufs.lcfg_buflen));
+       if (!lcfg)
                RETURN_EXIT;
-       }
+       lustre_cfg_init(lcfg, LCFG_CLEANUP, &bufs);
 
        LASSERT(top);
        top->ld_ops->ldo_process_config(env, top, lcfg);
-       lustre_cfg_free(lcfg);
+       OBD_FREE(lcfg, lustre_cfg_len(lcfg->lcfg_bufcount, lcfg->lcfg_buflens));
 
        lu_site_purge(env, top->ld_site, ~0);
        if (!cfs_hash_is_empty(top->ld_site->ls_obj_hash)) {
@@ -192,16 +264,24 @@ static struct cfg_interop_param ofd_interop_param[] = {
        { NULL }
 };
 
-/* Some parameters were moved from ofd to osd and only their
+/**
+ * Check if parameters are symlinks to the OSD.
+ *
+ * Some parameters were moved from ofd to osd and only their
  * symlinks were kept in ofd by LU-3106. They are:
  * -writehthrough_cache_enable
- * -readcache_max_filese
+ * -readcache_max_filesize
  * -read_cache_enable
  * -brw_stats
- * Since they are not included by the static lprocfs var list,
- * a pre-check is added for them to avoid "unknown param" error
- * message confuses the customer. If they are matched in this
- * check, they will be passed to the osd directly.
+ *
+ * Since they are not included by the static lprocfs var list, a pre-check
+ * is added for them to avoid "unknown param" errors. If they are matched
+ * in this check, they will be passed to the OSD directly.
+ *
+ * \param[in] param    parameters to check
+ *
+ * \retval             true if param is symlink to OSD param
+ *                     false otherwise
  */
 static bool match_symlink_param(char *param)
 {
@@ -226,7 +306,19 @@ static bool match_symlink_param(char *param)
        return false;
 }
 
-/* used by MGS to process specific configurations */
+/**
+ * Process various configuration parameters.
+ *
+ * This function is used by MGS to process specific configurations and
+ * pass them through to the next device in server stack, i.e. the OSD.
+ *
+ * \param[in] env      execution environment
+ * \param[in] d                LU device of OFD
+ * \param[in] cfg      parameters to process
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_process_config(const struct lu_env *env, struct lu_device *d,
                              struct lustre_cfg *cfg)
 {
@@ -239,8 +331,7 @@ static int ofd_process_config(const struct lu_env *env, struct lu_device *d,
 
        switch (cfg->lcfg_command) {
        case LCFG_PARAM: {
-               struct lprocfs_static_vars lvars;
-
+               struct obd_device       *obd = ofd_obd(m);
                /* For interoperability */
                struct cfg_interop_param   *ptr = NULL;
                struct lustre_cfg          *old_cfg = NULL;
@@ -278,8 +369,7 @@ static int ofd_process_config(const struct lu_env *env, struct lu_device *d,
                        break;
                }
 
-               lprocfs_ofd_init_vars(&lvars);
-               rc = class_process_proc_param(PARAM_OST, lvars.obd_vars, cfg,
+               rc = class_process_proc_param(PARAM_OST, obd->obd_vars, cfg,
                                              d->ld_obd);
                if (rc > 0 || rc == -ENOSYS) {
                        CDEBUG(D_CONFIG, "pass param %s down the stack.\n",
@@ -301,6 +391,18 @@ static int ofd_process_config(const struct lu_env *env, struct lu_device *d,
        RETURN(rc);
 }
 
+/**
+ * Implementation of lu_object_operations::loo_object_init for OFD
+ *
+ * Allocate just the next object (OSD) in stack.
+ *
+ * \param[in] env      execution environment
+ * \param[in] o                lu_object of OFD object
+ * \param[in] conf     additional configuration parameters, not used here
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_object_init(const struct lu_env *env, struct lu_object *o,
                           const struct lu_object_conf *conf)
 {
@@ -324,6 +426,14 @@ static int ofd_object_init(const struct lu_env *env, struct lu_object *o,
        RETURN(rc);
 }
 
+/**
+ * Implementation of lu_object_operations::loo_object_free.
+ *
+ * Finish OFD object lifecycle and free its memory.
+ *
+ * \param[in] env      execution environment
+ * \param[in] o                LU object of OFD object
+ */
 static void ofd_object_free(const struct lu_env *env, struct lu_object *o)
 {
        struct ofd_object       *of = ofd_obj(o);
@@ -341,18 +451,45 @@ static void ofd_object_free(const struct lu_env *env, struct lu_object *o)
        EXIT;
 }
 
+/**
+ * Implementation of lu_object_operations::loo_object_print.
+ *
+ * Print OFD part of compound OFD-OSD object. See lu_object_print() and
+ * LU_OBJECT_DEBUG() for more details about the compound object printing.
+ *
+ * \param[in] env      execution environment
+ * \param[in] cookie   opaque data passed to the printer function
+ * \param[in] p                printer function to use
+ * \param[in] o                LU object of OFD object
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_object_print(const struct lu_env *env, void *cookie,
                            lu_printer_t p, const struct lu_object *o)
 {
        return (*p)(env, cookie, LUSTRE_OST_NAME"-object@%p", o);
 }
 
-struct lu_object_operations ofd_obj_ops = {
+static struct lu_object_operations ofd_obj_ops = {
        .loo_object_init        = ofd_object_init,
        .loo_object_free        = ofd_object_free,
        .loo_object_print       = ofd_object_print
 };
 
+/**
+ * Implementation of lu_device_operations::lod_object_alloc.
+ *
+ * This function allocates OFD part of compound OFD-OSD object and
+ * initializes its header, because OFD is the top device in stack
+ *
+ * \param[in] env      execution environment
+ * \param[in] hdr      object header, NULL for OFD
+ * \param[in] d                lu_device
+ *
+ * \retval             allocated object if successful
+ * \retval             NULL value on failed allocation
+ */
 static struct lu_object *ofd_object_alloc(const struct lu_env *env,
                                          const struct lu_object_header *hdr,
                                          struct lu_device *d)
@@ -378,8 +515,19 @@ static struct lu_object *ofd_object_alloc(const struct lu_env *env,
        }
 }
 
-extern int ost_handle(struct ptlrpc_request *req);
-
+/**
+ * Return the result of LFSCK run to the OFD.
+ *
+ * Notify OFD about result of LFSCK run. That may block the new object
+ * creation until problem is fixed by LFSCK.
+ *
+ * \param[in] env      execution environment
+ * \param[in] data     pointer to the OFD device
+ * \param[in] event    LFSCK event type
+ *
+ * \retval             0 if successful
+ * \retval             negative value on unknown event
+ */
 static int ofd_lfsck_out_notify(const struct lu_env *env, void *data,
                                enum lfsck_events event)
 {
@@ -401,6 +549,8 @@ static int ofd_lfsck_out_notify(const struct lu_env *env, void *data,
                ofd->ofd_lastid_rebuilding = 0;
                ofd->ofd_lastid_gen++;
                up_write(&ofd->ofd_lastid_rwsem);
+               CWARN("%s: Rebuilt crashed LAST_ID files successfully.\n",
+                     obd->obd_name);
                break;
        }
        default:
@@ -412,6 +562,20 @@ static int ofd_lfsck_out_notify(const struct lu_env *env, void *data,
        return 0;
 }
 
+/**
+ * Implementation of lu_device_operations::ldo_prepare.
+ *
+ * This method is called after layer has been initialized and before it starts
+ * serving user requests. In OFD it starts lfsk check routines and initializes
+ * recovery.
+ *
+ * \param[in] env      execution environment
+ * \param[in] pdev     higher device in stack, NULL for OFD
+ * \param[in] dev      lu_device of OFD device
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_prepare(const struct lu_env *env, struct lu_device *pdev,
                       struct lu_device *dev)
 {
@@ -457,27 +621,49 @@ static int ofd_prepare(const struct lu_env *env, struct lu_device *pdev,
        RETURN(rc);
 }
 
+/**
+ * Implementation of lu_device_operations::ldo_recovery_complete.
+ *
+ * This method notifies all layers about 'recovery complete' event. That means
+ * device is in full state and consistent. An OFD calculates available grant
+ * space upon this event.
+ *
+ * \param[in] env      execution environment
+ * \param[in] dev      lu_device of OFD device
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_recovery_complete(const struct lu_env *env,
                                 struct lu_device *dev)
 {
+       struct ofd_thread_info  *oti = ofd_info(env);
        struct ofd_device       *ofd = ofd_dev(dev);
        struct lu_device        *next = &ofd->ofd_osd->dd_lu_dev;
-       int                      rc = 0, max_precreate;
+       int                      rc = 0;
 
        ENTRY;
 
-       /* Grant space for object precreation on the self export.
-        * This initial reserved space (i.e. 10MB for zfs and 280KB for ldiskfs)
+       /*
+        * Grant space for object precreation on the self export.
+        * The initial reserved space (i.e. 10MB for zfs and 280KB for ldiskfs)
         * is enough to create 10k objects. More space is then acquired for
-        * precreation in ofd_grant_create().
+        * precreation in tgt_grant_create().
         */
-       max_precreate = OST_MAX_PRECREATE * ofd->ofd_dt_conf.ddp_inodespace / 2;
-       ofd_grant_connect(env, dev->ld_obd->obd_self_export, max_precreate,
-                         false);
+       memset(&oti->fti_ocd, 0, sizeof(oti->fti_ocd));
+       oti->fti_ocd.ocd_grant = OST_MAX_PRECREATE / 2;
+       oti->fti_ocd.ocd_grant *= ofd->ofd_lut.lut_dt_conf.ddp_inodespace;
+       oti->fti_ocd.ocd_connect_flags = OBD_CONNECT_GRANT |
+                                        OBD_CONNECT_GRANT_PARAM;
+       tgt_grant_connect(env, dev->ld_obd->obd_self_export, &oti->fti_ocd,
+                         true);
        rc = next->ld_ops->ldo_recovery_complete(env, next);
        RETURN(rc);
 }
 
+/**
+ * lu_device_operations matrix for OFD device.
+ */
 static struct lu_device_operations ofd_lu_ops = {
        .ldo_object_alloc       = ofd_object_alloc,
        .ldo_process_config     = ofd_process_config,
@@ -485,19 +671,28 @@ static struct lu_device_operations ofd_lu_ops = {
        .ldo_prepare            = ofd_prepare,
 };
 
+LPROC_SEQ_FOPS(lprocfs_nid_stats_clear);
+
+/**
+ * Initialize all needed procfs entries for OFD device.
+ *
+ * \param[in] ofd      OFD device
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_procfs_init(struct ofd_device *ofd)
 {
-       struct lprocfs_static_vars       lvars;
        struct obd_device               *obd = ofd_obd(ofd);
-       cfs_proc_dir_entry_t            *entry;
+       struct proc_dir_entry           *entry;
        int                              rc = 0;
 
        ENTRY;
 
        /* lprocfs must be setup before the ofd so state can be safely added
         * to /proc incrementally as the ofd is setup */
-       lprocfs_ofd_init_vars(&lvars);
-       rc = lprocfs_obd_setup(obd, lvars.obd_vars);
+       obd->obd_vars = lprocfs_ofd_obd_vars;
+       rc = lprocfs_obd_setup(obd);
        if (rc) {
                CERROR("%s: lprocfs_obd_setup failed: %d.\n",
                       obd->obd_name, rc);
@@ -523,8 +718,7 @@ static int ofd_procfs_init(struct ofd_device *ofd)
        obd->obd_proc_exports_entry = entry;
 
        entry = lprocfs_add_simple(obd->obd_proc_exports_entry, "clear",
-                                  lprocfs_nid_stats_clear_read,
-                                  lprocfs_nid_stats_clear_write, obd, NULL);
+                                  obd, &lprocfs_nid_stats_clear_fops);
        if (IS_ERR(entry)) {
                rc = PTR_ERR(entry);
                CERROR("%s: add proc entry 'clear' failed: %d.\n",
@@ -537,10 +731,8 @@ static int ofd_procfs_init(struct ofd_device *ofd)
        rc = lprocfs_job_stats_init(obd, LPROC_OFD_STATS_LAST,
                                    ofd_stats_counter_init);
        if (rc)
-               GOTO(remove_entry_clear, rc);
+               GOTO(obd_cleanup, rc);
        RETURN(0);
-remove_entry_clear:
-       lprocfs_remove_proc_entry("clear", obd->obd_proc_exports_entry);
 obd_cleanup:
        lprocfs_obd_cleanup(obd);
        lprocfs_free_obd_stats(obd);
@@ -548,64 +740,90 @@ obd_cleanup:
        return rc;
 }
 
+/**
+ * Expose OSD statistics to OFD layer.
+ *
+ * The osd interfaces to the backend file system exposes useful data
+ * such as brw_stats and read or write cache states. This same data
+ * needs to be exposed into the obdfilter (ofd) layer to maintain
+ * backwards compatibility. This function creates the symlinks in the
+ * proc layer to enable this.
+ *
+ * \param[in] ofd      OFD device
+ */
 static void ofd_procfs_add_brw_stats_symlink(struct ofd_device *ofd)
 {
        struct obd_device       *obd = ofd_obd(ofd);
        struct obd_device       *osd_obd = ofd->ofd_osd_exp->exp_obd;
-       cfs_proc_dir_entry_t    *osd_root = osd_obd->obd_type->typ_procroot;
-       cfs_proc_dir_entry_t    *osd_dir;
 
-       osd_dir = lprocfs_srch(osd_root, obd->obd_name);
-       if (osd_dir == NULL)
+       if (obd->obd_proc_entry == NULL)
                return;
 
-       if (lprocfs_srch(osd_dir, "brw_stats") != NULL)
-               lprocfs_add_symlink("brw_stats", obd->obd_proc_entry,
-                                   "../../%s/%s/brw_stats",
-                                   osd_root->name, osd_dir->name);
-
-       if (lprocfs_srch(osd_dir, "read_cache_enable") != NULL)
-               lprocfs_add_symlink("read_cache_enable", obd->obd_proc_entry,
-                                   "../../%s/%s/read_cache_enable",
-                                   osd_root->name, osd_dir->name);
-
-       if (lprocfs_srch(osd_dir, "readcache_max_filesize") != NULL)
-               lprocfs_add_symlink("readcache_max_filesize",
-                                   obd->obd_proc_entry,
-                                   "../../%s/%s/readcache_max_filesize",
-                                   osd_root->name, osd_dir->name);
-
-       if (lprocfs_srch(osd_dir, "writethrough_cache_enable") != NULL)
-               lprocfs_add_symlink("writethrough_cache_enable",
-                                   obd->obd_proc_entry,
-                                   "../../%s/%s/writethrough_cache_enable",
-                                   osd_root->name, osd_dir->name);
+       lprocfs_add_symlink("brw_stats", obd->obd_proc_entry,
+                           "../../%s/%s/brw_stats",
+                           osd_obd->obd_type->typ_name, obd->obd_name);
+
+       lprocfs_add_symlink("read_cache_enable", obd->obd_proc_entry,
+                           "../../%s/%s/read_cache_enable",
+                           osd_obd->obd_type->typ_name, obd->obd_name);
+
+       lprocfs_add_symlink("readcache_max_filesize",
+                           obd->obd_proc_entry,
+                           "../../%s/%s/readcache_max_filesize",
+                           osd_obd->obd_type->typ_name, obd->obd_name);
+
+       lprocfs_add_symlink("writethrough_cache_enable",
+                           obd->obd_proc_entry,
+                           "../../%s/%s/writethrough_cache_enable",
+                           osd_obd->obd_type->typ_name, obd->obd_name);
 }
 
+/**
+ * Cleanup all procfs entries in OFD.
+ *
+ * \param[in] ofd      OFD device
+ */
 static void ofd_procfs_fini(struct ofd_device *ofd)
 {
        struct obd_device *obd = ofd_obd(ofd);
 
-       lprocfs_remove_proc_entry("writethrough_cache_enable",
-                                 obd->obd_proc_entry);
-       lprocfs_remove_proc_entry("readcache_max_filesize",
-                                 obd->obd_proc_entry);
-       lprocfs_remove_proc_entry("read_cache_enable", obd->obd_proc_entry);
-       lprocfs_remove_proc_entry("brw_stats", obd->obd_proc_entry);
-       lprocfs_remove_proc_entry("clear", obd->obd_proc_exports_entry);
        lprocfs_free_per_client_stats(obd);
        lprocfs_obd_cleanup(obd);
        lprocfs_free_obd_stats(obd);
        lprocfs_job_stats_fini(obd);
 }
 
-extern int ost_handle(struct ptlrpc_request *req);
-
+/**
+ * Stop SEQ/FID server on OFD.
+ *
+ * \param[in] env      execution environment
+ * \param[in] ofd      OFD device
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 int ofd_fid_fini(const struct lu_env *env, struct ofd_device *ofd)
 {
        return seq_site_fini(env, &ofd->ofd_seq_site);
 }
 
+/**
+ * Start SEQ/FID server on OFD.
+ *
+ * The SEQ/FID server on OFD is needed to allocate FIDs for new objects.
+ * It also connects to the master server to get own FID sequence (SEQ) range
+ * to this particular OFD. Typically that happens when the OST is first
+ * formatted or in the rare case that it exhausts the local sequence range.
+ *
+ * The sequence range is allocated out to the MDTs for OST object allocations,
+ * and not directly to the clients.
+ *
+ * \param[in] env      execution environment
+ * \param[in] ofd      OFD device
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 int ofd_fid_init(const struct lu_env *env, struct ofd_device *ofd)
 {
        struct seq_server_site  *ss = &ofd->ofd_seq_site;
@@ -619,72 +837,73 @@ int ofd_fid_init(const struct lu_env *env, struct ofd_device *ofd)
        ss->ss_lu = lu->ld_site;
        ss->ss_node_id = ofd->ofd_lut.lut_lsd.lsd_osd_index;
 
+       OBD_ALLOC(name, sizeof(obd_name) * 2 + 10);
+       if (name == NULL)
+               return -ENOMEM;
+
        OBD_ALLOC_PTR(ss->ss_server_seq);
        if (ss->ss_server_seq == NULL)
-               GOTO(out_free, rc = -ENOMEM);
-
-       OBD_ALLOC(name, strlen(obd_name) + 10);
-       if (!name) {
-               OBD_FREE_PTR(ss->ss_server_seq);
-               ss->ss_server_seq = NULL;
-               GOTO(out_free, rc = -ENOMEM);
-       }
+               GOTO(out_name, rc = -ENOMEM);
 
        rc = seq_server_init(env, ss->ss_server_seq, ofd->ofd_osd, obd_name,
                             LUSTRE_SEQ_SERVER, ss);
        if (rc) {
                CERROR("%s : seq server init error %d\n", obd_name, rc);
-               GOTO(out_free, rc);
+               GOTO(out_server, rc);
        }
        ss->ss_server_seq->lss_space.lsr_index = ss->ss_node_id;
 
        OBD_ALLOC_PTR(ss->ss_client_seq);
        if (ss->ss_client_seq == NULL)
-               GOTO(out_free, rc = -ENOMEM);
+               GOTO(out_server, rc = -ENOMEM);
 
-       snprintf(name, strlen(obd_name) + 6, "%p-super", obd_name);
+       /*
+        * It always printed as "%p", so that the name is unique in the kernel,
+        * even if the filesystem is mounted twice. So sizeof(.) * 2 is enough.
+        */
+       snprintf(name, sizeof(obd_name) * 2 + 7, "%p-super", obd_name);
        rc = seq_client_init(ss->ss_client_seq, NULL, LUSTRE_SEQ_DATA,
                             name, NULL);
        if (rc) {
                CERROR("%s : seq client init error %d\n", obd_name, rc);
-               GOTO(out_free, rc);
+               GOTO(out_client, rc);
        }
-       OBD_FREE(name, strlen(obd_name) + 10);
-       name = NULL;
 
        rc = seq_server_set_cli(env, ss->ss_server_seq, ss->ss_client_seq);
 
-out_free:
        if (rc) {
-               if (ss->ss_server_seq) {
-                       seq_server_fini(ss->ss_server_seq, env);
-                       OBD_FREE_PTR(ss->ss_server_seq);
-                       ss->ss_server_seq = NULL;
-               }
-
-               if (ss->ss_client_seq) {
-                       seq_client_fini(ss->ss_client_seq);
-                       OBD_FREE_PTR(ss->ss_client_seq);
-                       ss->ss_client_seq = NULL;
-               }
-
-               if (name) {
-                       OBD_FREE(name, strlen(obd_name) + 10);
-                       name = NULL;
-               }
+out_client:
+               seq_client_fini(ss->ss_client_seq);
+               OBD_FREE_PTR(ss->ss_client_seq);
+               ss->ss_client_seq = NULL;
+out_server:
+               seq_server_fini(ss->ss_server_seq, env);
+               OBD_FREE_PTR(ss->ss_server_seq);
+               ss->ss_server_seq = NULL;
        }
+out_name:
+       OBD_FREE(name, sizeof(obd_name) * 2 + 10);
 
        return rc;
 }
 
-int ofd_set_info_hdl(struct tgt_session_info *tsi)
+/**
+ * OFD request handler for OST_SET_INFO RPC.
+ *
+ * This is OFD-specific part of request handling
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
+static int ofd_set_info_hdl(struct tgt_session_info *tsi)
 {
        struct ptlrpc_request   *req = tgt_ses_req(tsi);
        struct ost_body         *body = NULL, *repbody;
        void                    *key, *val = NULL;
        int                      keylen, vallen, rc = 0;
        bool                     is_grant_shrink;
-       struct ofd_device       *ofd = ofd_exp(tsi->tsi_exp);
 
        ENTRY;
 
@@ -721,16 +940,12 @@ int ofd_set_info_hdl(struct tgt_session_info *tsi)
                *repbody = *body;
 
                /** handle grant shrink, similar to a read request */
-               ofd_grant_prepare_read(tsi->tsi_env, tsi->tsi_exp,
+               tgt_grant_prepare_read(tsi->tsi_env, tsi->tsi_exp,
                                       &repbody->oa);
        } else if (KEY_IS(KEY_EVICT_BY_NID)) {
                if (vallen > 0)
                        obd_export_evict_by_nid(tsi->tsi_exp->exp_obd, val);
                rc = 0;
-       } else if (KEY_IS(KEY_CAPA_KEY)) {
-               rc = ofd_update_capa_key(ofd, val);
-       } else if (KEY_IS(KEY_SPTLRPC_CONF)) {
-               rc = tgt_adapt_sptlrpc_conf(tsi->tsi_tgt, 0);
        } else {
                CERROR("%s: Unsupported key %s\n",
                       tgt_name(tsi->tsi_tgt), (char *)key);
@@ -742,8 +957,22 @@ int ofd_set_info_hdl(struct tgt_session_info *tsi)
        RETURN(rc);
 }
 
+/**
+ * Get FIEMAP (FIle Extent MAPping) for object with the given FID.
+ *
+ * This function returns a list of extents which describes how a file's
+ * blocks are laid out on the disk.
+ *
+ * \param[in] env      execution environment
+ * \param[in] ofd      OFD device
+ * \param[in] fid      FID of object
+ * \param[in] fiemap   fiemap structure to fill with data
+ *
+ * \retval             0 if \a fiemap is filled with data successfully
+ * \retval             negative value on error
+ */
 int ofd_fiemap_get(const struct lu_env *env, struct ofd_device *ofd,
-                  struct lu_fid *fid, struct ll_user_fiemap *fiemap)
+                  struct lu_fid *fid, struct fiemap *fiemap)
 {
        struct ofd_object       *fo;
        int                      rc;
@@ -766,13 +995,29 @@ int ofd_fiemap_get(const struct lu_env *env, struct ofd_device *ofd,
 }
 
 struct locked_region {
-       cfs_list_t              list;
+       struct list_head        list;
        struct lustre_handle    lh;
 };
 
+/**
+ * Lock single extent and save lock handle in the list.
+ *
+ * This is supplemental function for lock_zero_regions(). It allocates
+ * new locked_region structure and locks it with extent lock, then adds
+ * it to the list of all such regions.
+ *
+ * \param[in] ns       LDLM namespace
+ * \param[in] res_id   resource ID
+ * \param[in] begin    start of region
+ * \param[in] end      end of region
+ * \param[in] locked   list head of regions list
+ *
+ * \retval             0 if successful locking
+ * \retval             negative value on error
+ */
 static int lock_region(struct ldlm_namespace *ns, struct ldlm_res_id *res_id,
                       unsigned long long begin, unsigned long long end,
-                      cfs_list_t *locked)
+                      struct list_head *locked)
 {
        struct locked_region    *region = NULL;
        __u64                    flags = 0;
@@ -790,20 +1035,38 @@ static int lock_region(struct ldlm_namespace *ns, struct ldlm_res_id *res_id,
 
        CDEBUG(D_OTHER, "ost lock [%llu,%llu], lh=%p\n", begin, end,
               &region->lh);
-       cfs_list_add(&region->list, locked);
+       list_add(&region->list, locked);
 
        return 0;
 }
 
+/**
+ * Lock the sparse areas of given resource.
+ *
+ * The locking of sparse areas will cause dirty data to be flushed back from
+ * clients. This is used when getting the FIEMAP of an object to make sure
+ * there is no unaccounted cached data on clients.
+ *
+ * This function goes through \a fiemap list of extents and locks only sparse
+ * areas between extents.
+ *
+ * \param[in] ns       LDLM namespace
+ * \param[in] res_id   resource ID
+ * \param[in] fiemap   file extents mapping on disk
+ * \param[in] locked   list head of regions list
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int lock_zero_regions(struct ldlm_namespace *ns,
                             struct ldlm_res_id *res_id,
-                            struct ll_user_fiemap *fiemap,
-                            cfs_list_t *locked)
+                            struct fiemap *fiemap,
+                            struct list_head *locked)
 {
        __u64 begin = fiemap->fm_start;
        unsigned int i;
        int rc = 0;
-       struct ll_fiemap_extent *fiemap_start = fiemap->fm_extents;
+       struct fiemap_extent *fiemap_start = fiemap->fm_extents;
 
        ENTRY;
 
@@ -831,19 +1094,47 @@ static int lock_zero_regions(struct ldlm_namespace *ns,
        RETURN(rc);
 }
 
-static void unlock_zero_regions(struct ldlm_namespace *ns, cfs_list_t *locked)
+/**
+ * Unlock all previously locked sparse areas for given resource.
+ *
+ * This function goes through list of locked regions, unlocking and freeing
+ * them one-by-one.
+ *
+ * \param[in] ns       LDLM namespace
+ * \param[in] locked   list head of regions list
+ */
+static void
+unlock_zero_regions(struct ldlm_namespace *ns, struct list_head *locked)
 {
        struct locked_region *entry, *temp;
 
-       cfs_list_for_each_entry_safe(entry, temp, locked, list) {
+       list_for_each_entry_safe(entry, temp, locked, list) {
                CDEBUG(D_OTHER, "ost unlock lh=%p\n", &entry->lh);
                tgt_extent_unlock(&entry->lh, LCK_PR);
-               cfs_list_del(&entry->list);
+               list_del(&entry->list);
                OBD_FREE_PTR(entry);
        }
 }
 
-int ofd_get_info_hdl(struct tgt_session_info *tsi)
+/**
+ * OFD request handler for OST_GET_INFO RPC.
+ *
+ * This is OFD-specific part of request handling. The OFD-specific keys are:
+ * - KEY_LAST_ID (obsolete)
+ * - KEY_FIEMAP
+ * - KEY_LAST_FID
+ *
+ * This function reads needed data from storage and fills reply with it.
+ *
+ * Note: the KEY_LAST_ID is obsolete, replaced by KEY_LAST_FID on newer MDTs,
+ * and is kept for compatibility.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
+static int ofd_get_info_hdl(struct tgt_session_info *tsi)
 {
        struct obd_export               *exp = tsi->tsi_exp;
        struct ofd_device               *ofd = ofd_exp(exp);
@@ -864,7 +1155,7 @@ int ofd_get_info_hdl(struct tgt_session_info *tsi)
                                      RCL_CLIENT);
 
        if (KEY_IS(KEY_LAST_ID)) {
-               obd_id          *last_id;
+               u64             *last_id;
                struct ofd_seq  *oseq;
 
                req_capsule_extend(tsi->tsi_pill, &RQF_OST_GET_INFO_LAST_ID);
@@ -875,7 +1166,7 @@ int ofd_get_info_hdl(struct tgt_session_info *tsi)
                last_id = req_capsule_server_get(tsi->tsi_pill, &RMF_OBD_ID);
 
                oseq = ofd_seq_load(tsi->tsi_env, ofd,
-                                   (obd_seq)exp->exp_filter_data.fed_group);
+                                   (u64)exp->exp_filter_data.fed_group);
                if (IS_ERR(oseq))
                        rc = -EFAULT;
                else
@@ -883,21 +1174,22 @@ int ofd_get_info_hdl(struct tgt_session_info *tsi)
                ofd_seq_put(tsi->tsi_env, oseq);
        } else if (KEY_IS(KEY_FIEMAP)) {
                struct ll_fiemap_info_key       *fm_key;
-               struct ll_user_fiemap           *fiemap;
+               struct fiemap                   *fiemap;
                struct lu_fid                   *fid;
 
                req_capsule_extend(tsi->tsi_pill, &RQF_OST_GET_INFO_FIEMAP);
 
                fm_key = req_capsule_client_get(tsi->tsi_pill, &RMF_FIEMAP_KEY);
-               rc = tgt_validate_obdo(tsi, &fm_key->oa);
+               rc = tgt_validate_obdo(tsi, &fm_key->lfik_oa);
                if (rc)
                        RETURN(err_serious(rc));
 
-               fid = &fm_key->oa.o_oi.oi_fid;
+               fid = &fm_key->lfik_oa.o_oi.oi_fid;
 
                CDEBUG(D_INODE, "get FIEMAP of object "DFID"\n", PFID(fid));
 
-               replylen = fiemap_count_to_size(fm_key->fiemap.fm_extent_count);
+               replylen = fiemap_count_to_size(
+                                       fm_key->lfik_fiemap.fm_extent_count);
                req_capsule_set_size(tsi->tsi_pill, &RMF_FIEMAP_VAL,
                                     RCL_SERVER, replylen);
 
@@ -909,20 +1201,21 @@ int ofd_get_info_hdl(struct tgt_session_info *tsi)
                if (fiemap == NULL)
                        RETURN(-ENOMEM);
 
-               *fiemap = fm_key->fiemap;
+               *fiemap = fm_key->lfik_fiemap;
                rc = ofd_fiemap_get(tsi->tsi_env, ofd, fid, fiemap);
 
                /* LU-3219: Lock the sparse areas to make sure dirty
                 * flushed back from client, then call fiemap again. */
-               if (fm_key->oa.o_valid & OBD_MD_FLFLAGS &&
-                   fm_key->oa.o_flags & OBD_FL_SRVLOCK) {
-                       cfs_list_t locked = CFS_LIST_HEAD_INIT(locked);
+               if (fm_key->lfik_oa.o_valid & OBD_MD_FLFLAGS &&
+                   fm_key->lfik_oa.o_flags & OBD_FL_SRVLOCK) {
+                       struct list_head locked;
 
+                       INIT_LIST_HEAD(&locked);
                        ost_fid_build_resid(fid, &fti->fti_resid);
                        rc = lock_zero_regions(ofd->ofd_namespace,
                                               &fti->fti_resid, fiemap,
                                               &locked);
-                       if (rc == 0 && !cfs_list_empty(&locked)) {
+                       if (rc == 0 && !list_empty(&locked)) {
                                rc = ofd_fiemap_get(tsi->tsi_env, ofd, fid,
                                                    fiemap);
                                unlock_zero_regions(ofd->ofd_namespace,
@@ -975,6 +1268,17 @@ out_put:
        RETURN(rc);
 }
 
+/**
+ * OFD request handler for OST_GETATTR RPC.
+ *
+ * This is OFD-specific part of request handling. It finds the OFD object
+ * by its FID, gets attributes from storage and packs result to the reply.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_getattr_hdl(struct tgt_session_info *tsi)
 {
        struct ofd_thread_info  *fti = tsi2ofd_info(tsi);
@@ -983,7 +1287,7 @@ static int ofd_getattr_hdl(struct tgt_session_info *tsi)
        struct lustre_handle     lh = { 0 };
        struct ofd_object       *fo;
        __u64                    flags = 0;
-       ldlm_mode_t              lock_mode = LCK_PR;
+       enum ldlm_mode           lock_mode = LCK_PR;
        bool                     srvlock;
        int                      rc;
        ENTRY;
@@ -1020,8 +1324,7 @@ static int ofd_getattr_hdl(struct tgt_session_info *tsi)
                __u64    curr_version;
 
                obdo_from_la(&repbody->oa, &fti->fti_attr,
-                            OFD_VALID_FLAGS | LA_UID | LA_GID);
-               tgt_drop_id(tsi->tsi_exp, &repbody->oa);
+                            OFD_VALID_FLAGS | LA_UID | LA_GID | LA_PROJID);
 
                /* Store object version in reply */
                curr_version = dt_version_get(tsi->tsi_env,
@@ -1046,6 +1349,17 @@ out:
        RETURN(rc);
 }
 
+/**
+ * OFD request handler for OST_SETATTR RPC.
+ *
+ * This is OFD-specific part of request handling. It finds the OFD object
+ * by its FID, sets attributes from request and packs result to the reply.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_setattr_hdl(struct tgt_session_info *tsi)
 {
        struct ofd_thread_info  *fti = tsi2ofd_info(tsi);
@@ -1105,8 +1419,7 @@ static int ofd_setattr_hdl(struct tgt_session_info *tsi)
                GOTO(out_put, rc);
 
        obdo_from_la(&repbody->oa, &fti->fti_attr,
-                    OFD_VALID_FLAGS | LA_UID | LA_GID);
-       tgt_drop_id(tsi->tsi_exp, &repbody->oa);
+                    OFD_VALID_FLAGS | LA_UID | LA_GID | LA_PROJID);
 
        ofd_counter_incr(tsi->tsi_exp, LPROC_OFD_STATS_SETATTR,
                         tsi->tsi_jobid, 1);
@@ -1130,6 +1443,20 @@ out:
        return rc;
 }
 
+/**
+ * Destroy OST orphans.
+ *
+ * This is part of OST_CREATE RPC handling. If there is flag OBD_FL_DELORPHAN
+ * set then we must destroy possible orphaned objects.
+ *
+ * \param[in] env      execution environment
+ * \param[in] exp      OBD export
+ * \param[in] ofd      OFD device
+ * \param[in] oa       obdo structure for reply
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_orphans_destroy(const struct lu_env *env,
                               struct obd_export *exp,
                               struct ofd_device *ofd, struct obdo *oa)
@@ -1138,10 +1465,10 @@ static int ofd_orphans_destroy(const struct lu_env *env,
        struct lu_fid           *fid    = &info->fti_fid;
        struct ost_id           *oi     = &oa->o_oi;
        struct ofd_seq          *oseq;
-       obd_seq                  seq    = ostid_seq(oi);
-       obd_id                   end_id = ostid_id(oi);
-       obd_id                   last;
-       obd_id                   oid;
+       u64                      seq    = ostid_seq(oi);
+       u64                      end_id = ostid_id(oi);
+       u64                      last;
+       u64                      oid;
        int                      skip_orphan;
        int                      rc     = 0;
 
@@ -1200,8 +1527,7 @@ done:
                rc = ofd_seq_last_oid_write(env, ofd, oseq);
        } else {
                /* don't reuse orphan object, return last used objid */
-               ostid_set_id(oi, last);
-               rc = 0;
+               rc = ostid_set_id(oi, last);
        }
 
        GOTO(out_put, rc);
@@ -1211,18 +1537,32 @@ out_put:
        return rc;
 }
 
+/**
+ * OFD request handler for OST_CREATE RPC.
+ *
+ * This is OFD-specific part of request handling. Its main purpose is to
+ * create new data objects on OST, but it also used to destroy orphans.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_create_hdl(struct tgt_session_info *tsi)
 {
+       struct ptlrpc_request   *req = tgt_ses_req(tsi);
        struct ost_body         *repbody;
        const struct obdo       *oa = &tsi->tsi_ost_body->oa;
        struct obdo             *rep_oa;
        struct obd_export       *exp = tsi->tsi_exp;
        struct ofd_device       *ofd = ofd_exp(exp);
-       obd_seq                  seq = ostid_seq(&oa->o_oi);
-       obd_id                   oid = ostid_id(&oa->o_oi);
+       u64                      seq = ostid_seq(&oa->o_oi);
+       u64                      oid = ostid_id(&oa->o_oi);
        struct ofd_seq          *oseq;
-       int                      rc = 0, diff;
+       s64 diff;
+       int rc = 0;
        int                      sync_trans = 0;
+       long                     granted = 0;
 
        ENTRY;
 
@@ -1243,14 +1583,13 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
        rep_oa = &repbody->oa;
        rep_oa->o_oi = oa->o_oi;
 
-       LASSERT(seq >= FID_SEQ_OST_MDT0);
        LASSERT(oa->o_valid & OBD_MD_FLGROUP);
 
        CDEBUG(D_INFO, "ofd_create("DOSTID")\n", POSTID(&oa->o_oi));
 
        oseq = ofd_seq_load(tsi->tsi_env, ofd, seq);
        if (IS_ERR(oseq)) {
-               CERROR("%s: Can't find FID Sequence "LPX64": rc = %ld\n",
+               CERROR("%s: Can't find FID Sequence %#llx: rc = %ld\n",
                       ofd_name(ofd), seq, PTR_ERR(oseq));
                GOTO(out_sem, rc = -EINVAL);
        }
@@ -1259,7 +1598,7 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
            (oa->o_flags & OBD_FL_RECREATE_OBJS)) {
                if (!ofd_obd(ofd)->obd_recovering ||
                    oid > ofd_seq_last_oid(oseq)) {
-                       CERROR("%s: recreate objid "DOSTID" > last id "LPU64
+                       CERROR("%s: recreate objid "DOSTID" > last id %llu"
                               "\n", ofd_name(ofd), POSTID(&oa->o_oi),
                               ofd_seq_last_oid(oseq));
                        GOTO(out_nolock, rc = -EINVAL);
@@ -1284,17 +1623,26 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
                oseq->os_destroys_in_progress = 1;
                mutex_lock(&oseq->os_create_lock);
                if (!oseq->os_destroys_in_progress) {
-                       CERROR("%s:["LPU64"] destroys_in_progress already"
+                       CERROR("%s:[%llu] destroys_in_progress already"
                               " cleared\n", ofd_name(ofd), seq);
-                       ostid_set_id(&rep_oa->o_oi, ofd_seq_last_oid(oseq));
-                       GOTO(out, rc = 0);
+                       rc = ostid_set_id(&rep_oa->o_oi,
+                                         ofd_seq_last_oid(oseq));
+                       GOTO(out, rc);
                }
                diff = oid - ofd_seq_last_oid(oseq);
-               CDEBUG(D_HA, "ofd_last_id() = "LPU64" -> diff = %d\n",
-                       ofd_seq_last_oid(oseq), diff);
+               CDEBUG(D_HA, "ofd_last_id() = %llu -> diff = %lld\n",
+                      ofd_seq_last_oid(oseq), diff);
                if (-diff > OST_MAX_PRECREATE) {
-                       /* FIXME: should reset precreate_next_id on MDS */
-                       rc = 0;
+                       LCONSOLE(D_INFO, "%s: too large difference between MDS "
+                                "LAST_ID "DFID" (%llu) and OST LAST_ID "DFID" "
+                                "(%llu), trust the OST\n",
+                                ofd_name(ofd), PFID(&oa->o_oi.oi_fid), oid,
+                                PFID(&oseq->os_oi.oi_fid),
+                                ofd_seq_last_oid(oseq));
+
+                       /* Let MDS know that we are so far ahead. */
+                       rc = ostid_set_id(&rep_oa->o_oi,
+                                         ofd_seq_last_oid(oseq) + 1);
                } else if (diff < 0) {
                        rc = ofd_orphans_destroy(tsi->tsi_env, exp,
                                                 ofd, rep_oa);
@@ -1306,7 +1654,8 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
        } else {
                if (unlikely(exp->exp_filter_data.fed_lastid_gen !=
                             ofd->ofd_lastid_gen)) {
-                       ofd_obd_disconnect(exp);
+                       /* Keep the export ref so we can send the reply. */
+                       ofd_obd_disconnect(class_export_get(exp));
                        GOTO(out_nolock, rc = -ENOTCONN);
                }
 
@@ -1337,23 +1686,35 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
                                       ofd_name(ofd), POSTID(&oa->o_oi));
                                GOTO(out, rc = -EINVAL);
                        }
+
+                       if (diff < 0) {
+                               /* LU-5648 */
+                               CERROR("%s: invalid precreate request for "
+                                      DOSTID", last_id %llu. "
+                                      "Likely MDS last_id corruption\n",
+                                      ofd_name(ofd), POSTID(&oa->o_oi),
+                                      ofd_seq_last_oid(oseq));
+                               GOTO(out, rc = -EINVAL);
+                       }
                }
        }
        if (diff > 0) {
                cfs_time_t       enough_time = cfs_time_shift(DISK_TIMEOUT);
-               obd_id           next_id;
+               u64              next_id;
                int              created = 0;
                int              count;
 
                if (!(oa->o_valid & OBD_MD_FLFLAGS) ||
                    !(oa->o_flags & OBD_FL_DELORPHAN)) {
                        /* don't enforce grant during orphan recovery */
-                       rc = ofd_grant_create(tsi->tsi_env,
-                                             ofd_obd(ofd)->obd_self_export,
-                                             &diff);
-                       if (rc) {
+                       granted = tgt_grant_create(tsi->tsi_env,
+                                               ofd_obd(ofd)->obd_self_export,
+                                               &diff);
+                       if (granted < 0) {
+                               rc = granted;
+                               granted = 0;
                                CDEBUG(D_HA, "%s: failed to acquire grant "
-                                      "space for precreate (%d): rc = %d\n",
+                                      "space for precreate (%lld): rc = %d\n",
                                       ofd_name(ofd), diff, rc);
                                diff = 0;
                        }
@@ -1366,29 +1727,34 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
                 * LFSCK will eventually clean up any orphans. LU-14 */
                if (diff > 5 * OST_MAX_PRECREATE) {
                        diff = OST_MAX_PRECREATE / 2;
-                       LCONSOLE_WARN("%s: precreate FID "DOSTID" is over %u "
-                                     "larger than the LAST_ID "DOSTID", only "
-                                     "precreating the last %u objects.\n",
-                                     ofd_name(ofd), POSTID(&oa->o_oi),
-                                     5 * OST_MAX_PRECREATE,
-                                     POSTID(&oseq->os_oi), diff);
+                       LCONSOLE_WARN("%s: Too many FIDs to precreate "
+                                     "OST replaced or reformatted: "
+                                     "LFSCK will clean up",
+                                     ofd_name(ofd));
+
+                       CDEBUG(D_HA, "%s: precreate FID "DOSTID" is over "
+                              "%u larger than the LAST_ID "DOSTID", only "
+                              "precreating the last %lld objects.\n",
+                              ofd_name(ofd), POSTID(&oa->o_oi),
+                              5 * OST_MAX_PRECREATE,
+                              POSTID(&oseq->os_oi), diff);
                        ofd_seq_last_oid_set(oseq, ostid_id(&oa->o_oi) - diff);
                }
 
                while (diff > 0) {
                        next_id = ofd_seq_last_oid(oseq) + 1;
-                       count = ofd_precreate_batch(ofd, diff);
+                       count = ofd_precreate_batch(ofd, (int)diff);
 
-                       CDEBUG(D_HA, "%s: reserve %d objects in group "LPX64
-                              " at "LPU64"\n", ofd_name(ofd),
+                       CDEBUG(D_HA, "%s: reserve %d objects in group %#llx"
+                              " at %llu\n", ofd_name(ofd),
                               count, seq, next_id);
 
-                       if (cfs_time_after(jiffies, enough_time)) {
-                               LCONSOLE_WARN("%s: Slow creates, %d/%d objects"
-                                             " created at a rate of %d/s\n",
-                                             ofd_name(ofd), created,
-                                             diff + created,
-                                             created / DISK_TIMEOUT);
+                       if (!(lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY)
+                           && cfs_time_after(jiffies, enough_time)) {
+                               CDEBUG(D_HA, "%s: Slow creates, %d/%lld objects"
+                                     " created at a rate of %d/s\n",
+                                     ofd_name(ofd), created, diff + created,
+                                     created / DISK_TIMEOUT);
                                break;
                        }
 
@@ -1401,6 +1767,14 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
                                break;
                        }
                }
+
+               if (diff > 0 &&
+                   lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY)
+                       LCONSOLE_WARN("%s: can't create the same count of"
+                                     " objects when replaying the request"
+                                     " (diff is %lld). see LU-4621\n",
+                                     ofd_name(ofd), diff);
+
                if (created > 0)
                        /* some objects got created, we can return
                         * them, even if last creation failed */
@@ -1410,11 +1784,13 @@ static int ofd_create_hdl(struct tgt_session_info *tsi)
                               ofd_name(ofd), rc);
 
                if (!(oa->o_valid & OBD_MD_FLFLAGS) ||
-                   !(oa->o_flags & OBD_FL_DELORPHAN))
-                       ofd_grant_commit(tsi->tsi_env,
-                                        ofd_obd(ofd)->obd_self_export, rc);
+                   !(oa->o_flags & OBD_FL_DELORPHAN)) {
+                       tgt_grant_commit(ofd_obd(ofd)->obd_self_export,
+                                        granted, rc);
+                       granted = 0;
+               }
 
-               ostid_set_id(&rep_oa->o_oi, ofd_seq_last_oid(oseq));
+               rc = ostid_set_id(&rep_oa->o_oi, ofd_seq_last_oid(oseq));
        }
        EXIT;
        ofd_counter_incr(exp, LPROC_OFD_STATS_CREATE,
@@ -1441,6 +1817,17 @@ out_sem:
        return rc;
 }
 
+/**
+ * OFD request handler for OST_DESTROY RPC.
+ *
+ * This is OFD-specific part of request handling. It destroys data objects
+ * related to destroyed object on MDT.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_destroy_hdl(struct tgt_session_info *tsi)
 {
        const struct ost_body   *body = tsi->tsi_ost_body;
@@ -1448,8 +1835,8 @@ static int ofd_destroy_hdl(struct tgt_session_info *tsi)
        struct ofd_device       *ofd = ofd_exp(tsi->tsi_exp);
        struct ofd_thread_info  *fti = tsi2ofd_info(tsi);
        struct lu_fid           *fid = &fti->fti_fid;
-       obd_id                   oid;
-       obd_count                count;
+       u64                      oid;
+       u32                      count;
        int                      rc = 0;
 
        ENTRY;
@@ -1466,7 +1853,7 @@ static int ofd_destroy_hdl(struct tgt_session_info *tsi)
                dlm = req_capsule_client_get(tsi->tsi_pill, &RMF_DLM_REQ);
                if (dlm == NULL)
                        RETURN(-EFAULT);
-               ldlm_request_cancel(tgt_ses_req(tsi), dlm, 0);
+               ldlm_request_cancel(tgt_ses_req(tsi), dlm, 0, LATF_SKIP);
        }
 
        *fid = body->oa.o_oi.oi_fid;
@@ -1518,6 +1905,17 @@ out:
        return rc;
 }
 
+/**
+ * OFD request handler for OST_STATFS RPC.
+ *
+ * This function gets statfs data from storage as part of request
+ * processing.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_statfs_hdl(struct tgt_session_info *tsi)
 {
        struct obd_statfs       *osfs;
@@ -1542,6 +1940,17 @@ static int ofd_statfs_hdl(struct tgt_session_info *tsi)
        RETURN(rc);
 }
 
+/**
+ * OFD request handler for OST_SYNC RPC.
+ *
+ * Sync object data or all filesystem data to the disk and pack the
+ * result in reply.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_sync_hdl(struct tgt_session_info *tsi)
 {
        struct ost_body         *body = tsi->tsi_ost_body;
@@ -1590,6 +1999,17 @@ put:
        return rc;
 }
 
+/**
+ * OFD request handler for OST_PUNCH RPC.
+ *
+ * This is part of request processing. Validate request fields,
+ * punch (truncate) the given OFD object and pack reply.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_punch_hdl(struct tgt_session_info *tsi)
 {
        const struct obdo       *oa = &tsi->tsi_ost_body->oa;
@@ -1607,6 +2027,8 @@ static int ofd_punch_hdl(struct tgt_session_info *tsi)
 
        ENTRY;
 
+       OBD_FAIL_TIMEOUT(OBD_FAIL_OST_PAUSE_PUNCH, cfs_fail_val);
+
        /* check that we do support OBD_CONNECT_TRUNCLOCK. */
        CLASSERT(OST_CONNECT_SUPPORTED & OBD_CONNECT_TRUNCLOCK);
 
@@ -1643,8 +2065,8 @@ static int ofd_punch_hdl(struct tgt_session_info *tsi)
                        RETURN(rc);
        }
 
-       CDEBUG(D_INODE, "calling punch for object "DFID", valid = "LPX64
-              ", start = "LPD64", end = "LPD64"\n", PFID(&tsi->tsi_fid),
+       CDEBUG(D_INODE, "calling punch for object "DFID", valid = %#llx"
+              ", start = %lld, end = %lld\n", PFID(&tsi->tsi_fid),
               oa->o_valid, start, end);
 
        fo = ofd_object_find_exists(tsi->tsi_env, ofd_exp(tsi->tsi_exp),
@@ -1691,10 +2113,201 @@ out:
        return rc;
 }
 
+static int ofd_ladvise_prefetch(const struct lu_env *env,
+                               struct ofd_object *fo,
+                               struct niobuf_local *lnb,
+                               __u64 start, __u64 end)
+{
+       struct ofd_thread_info  *info = ofd_info(env);
+       pgoff_t                  start_index, end_index, pages;
+       struct niobuf_remote     rnb;
+       unsigned long            nr_local;
+       int                      rc = 0;
+
+       if (end <= start)
+               RETURN(-EINVAL);
+
+       ofd_read_lock(env, fo);
+       if (!ofd_object_exists(fo))
+               GOTO(out_unlock, rc = -ENOENT);
+
+       rc = ofd_attr_get(env, fo, &info->fti_attr);
+       if (rc)
+               GOTO(out_unlock, rc);
+
+       if (end > info->fti_attr.la_size)
+               end = info->fti_attr.la_size;
+
+       if (end == 0)
+               GOTO(out_unlock, rc);
+
+       /* We need page aligned offset and length */
+       start_index = start >> PAGE_SHIFT;
+       end_index = (end - 1) >> PAGE_SHIFT;
+       pages = end_index - start_index + 1;
+       while (pages > 0) {
+               nr_local = pages <= PTLRPC_MAX_BRW_PAGES ? pages :
+                       PTLRPC_MAX_BRW_PAGES;
+               rnb.rnb_offset = start_index << PAGE_SHIFT;
+               rnb.rnb_len = nr_local << PAGE_SHIFT;
+               rc = dt_bufs_get(env, ofd_object_child(fo), &rnb, lnb, 0);
+               if (unlikely(rc < 0))
+                       break;
+               nr_local = rc;
+               rc = dt_read_prep(env, ofd_object_child(fo), lnb, nr_local);
+               dt_bufs_put(env, ofd_object_child(fo), lnb, nr_local);
+               if (unlikely(rc))
+                       break;
+               start_index += nr_local;
+               pages -= nr_local;
+       }
+
+out_unlock:
+       ofd_read_unlock(env, fo);
+       RETURN(rc);
+}
+
+/**
+ * OFD request handler for OST_LADVISE RPC.
+ *
+ * Tune cache or perfetch policies according to advices.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative errno on error
+ */
+static int ofd_ladvise_hdl(struct tgt_session_info *tsi)
+{
+       struct ptlrpc_request *req = tgt_ses_req(tsi);
+       struct obd_export *exp = tsi->tsi_exp;
+       struct ofd_device *ofd = ofd_exp(exp);
+       struct ost_body *body, *repbody;
+       struct ofd_thread_info *info;
+       struct ofd_object *fo;
+       struct ptlrpc_thread *svc_thread = req->rq_svc_thread;
+       const struct lu_env *env = svc_thread->t_env;
+       struct tgt_thread_big_cache *tbc = svc_thread->t_data;
+       int rc = 0;
+       struct lu_ladvise *ladvise;
+       int num_advise;
+       struct ladvise_hdr *ladvise_hdr;
+       struct obd_ioobj ioo;
+       struct lustre_handle lockh = { 0 };
+       __u64 flags = 0;
+       int i;
+       struct dt_object *dob;
+       __u64 start;
+       __u64 end;
+       ENTRY;
+
+       CFS_FAIL_TIMEOUT(OBD_FAIL_OST_LADVISE_PAUSE, cfs_fail_val);
+       body = tsi->tsi_ost_body;
+
+       if ((body->oa.o_valid & OBD_MD_FLID) != OBD_MD_FLID)
+               RETURN(err_serious(-EPROTO));
+
+       ladvise_hdr = req_capsule_client_get(tsi->tsi_pill,
+                                            &RMF_OST_LADVISE_HDR);
+       if (ladvise_hdr == NULL)
+               RETURN(err_serious(-EPROTO));
+
+       if (ladvise_hdr->lah_magic != LADVISE_MAGIC ||
+           ladvise_hdr->lah_count < 1)
+               RETURN(err_serious(-EPROTO));
+
+       if ((ladvise_hdr->lah_flags & (~LF_MASK)) != 0)
+               RETURN(err_serious(-EPROTO));
+
+       ladvise = req_capsule_client_get(tsi->tsi_pill, &RMF_OST_LADVISE);
+       if (ladvise == NULL)
+               RETURN(err_serious(-EPROTO));
+
+       num_advise = req_capsule_get_size(&req->rq_pill,
+                                         &RMF_OST_LADVISE, RCL_CLIENT) /
+                                         sizeof(*ladvise);
+       if (num_advise < ladvise_hdr->lah_count)
+               RETURN(err_serious(-EPROTO));
+
+       repbody = req_capsule_server_get(&req->rq_pill, &RMF_OST_BODY);
+       repbody->oa = body->oa;
+
+       info = ofd_info_init(env, exp);
+
+       rc = ostid_to_fid(&info->fti_fid, &body->oa.o_oi,
+                         ofd->ofd_lut.lut_lsd.lsd_osd_index);
+       if (rc != 0)
+               RETURN(rc);
+
+       fo = ofd_object_find(env, ofd, &info->fti_fid);
+       if (IS_ERR(fo)) {
+               rc = PTR_ERR(fo);
+               RETURN(rc);
+       }
+       LASSERT(fo != NULL);
+       dob = ofd_object_child(fo);
+
+       for (i = 0; i < num_advise; i++, ladvise++) {
+               start = ladvise->lla_start;
+               end = ladvise->lla_end;
+               if (end <= start) {
+                       rc = err_serious(-EPROTO);
+                       break;
+               }
+
+               /* Handle different advice types */
+               switch (ladvise->lla_advice) {
+               default:
+                       rc = -ENOTSUPP;
+                       break;
+               case LU_LADVISE_WILLREAD:
+                       if (tbc == NULL)
+                               RETURN(-ENOMEM);
+
+                       ioo.ioo_oid = body->oa.o_oi;
+                       ioo.ioo_bufcnt = 1;
+                       rc = tgt_extent_lock(exp->exp_obd->obd_namespace,
+                                            &tsi->tsi_resid, start, end - 1,
+                                            &lockh, LCK_PR, &flags);
+                       if (rc != 0)
+                               break;
+
+                       req->rq_status = ofd_ladvise_prefetch(env, fo,
+                                                             tbc->local,
+                                                             start, end);
+                       tgt_extent_unlock(&lockh, LCK_PR);
+                       break;
+               case LU_LADVISE_DONTNEED:
+                       rc = dt_ladvise(env, dob, ladvise->lla_start,
+                                       ladvise->lla_end, LU_LADVISE_DONTNEED);
+                       break;
+               }
+               if (rc != 0)
+                       break;
+       }
+
+       ofd_object_put(env, fo);
+       req->rq_status = rc;
+       RETURN(rc);
+}
+
+/**
+ * OFD request handler for OST_QUOTACTL RPC.
+ *
+ * This is part of request processing to validate incoming request fields,
+ * get the requested data from OSD and pack reply.
+ *
+ * \param[in] tsi      target session environment for this request
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_quotactl(struct tgt_session_info *tsi)
 {
-       struct obd_quotactl     *oqctl, *repoqc;
-       int                      rc;
+       struct obd_quotactl *oqctl, *repoqc;
+       struct lu_nodemap *nodemap;
+       int id;
+       int rc;
 
        ENTRY;
 
@@ -1706,77 +2319,101 @@ static int ofd_quotactl(struct tgt_session_info *tsi)
        if (repoqc == NULL)
                RETURN(err_serious(-ENOMEM));
 
-       /* report success for quota on/off for interoperability with current MDT
-        * stack */
-       if (oqctl->qc_cmd == Q_QUOTAON || oqctl->qc_cmd == Q_QUOTAOFF)
-               RETURN(0);
-
        *repoqc = *oqctl;
+
+       nodemap = nodemap_get_from_exp(tsi->tsi_exp);
+       if (IS_ERR(nodemap))
+               RETURN(PTR_ERR(nodemap));
+
+       id = repoqc->qc_id;
+       if (oqctl->qc_type == USRQUOTA)
+               id = nodemap_map_id(nodemap, NODEMAP_UID,
+                                   NODEMAP_CLIENT_TO_FS,
+                                   repoqc->qc_id);
+       else if (oqctl->qc_type == GRPQUOTA)
+               id = nodemap_map_id(nodemap, NODEMAP_GID,
+                                   NODEMAP_CLIENT_TO_FS,
+                                   repoqc->qc_id);
+
+       nodemap_putref(nodemap);
+
+       if (repoqc->qc_id != id)
+               swap(repoqc->qc_id, id);
+
        rc = lquotactl_slv(tsi->tsi_env, tsi->tsi_tgt->lut_bottom, repoqc);
 
        ofd_counter_incr(tsi->tsi_exp, LPROC_OFD_STATS_QUOTACTL,
                         tsi->tsi_jobid, 1);
 
+       if (repoqc->qc_id != id)
+               swap(repoqc->qc_id, id);
+
        RETURN(rc);
 }
 
-/* High priority request handlers for OFD */
-
-/* prolong locks for the current service time of the corresponding
- * portal (= OST_IO_PORTAL)
+/**
+ * Calculate the amount of time for lock prolongation.
+ *
+ * This is helper for ofd_prolong_extent_locks() function to get
+ * the timeout extra time.
+ *
+ * \param[in] req      current request
+ *
+ * \retval             amount of time to extend the timeout with
  */
 static inline int prolong_timeout(struct ptlrpc_request *req)
 {
        struct ptlrpc_service_part *svcpt = req->rq_rqbd->rqbd_svcpt;
+       time_t req_timeout;
 
        if (AT_OFF)
                return obd_timeout / 2;
 
-       return max(at_est2timeout(at_get(&svcpt->scp_at_estimate)),
-                  ldlm_timeout);
-}
-
-static int ofd_prolong_one_lock(struct tgt_session_info *tsi,
-                               struct ldlm_lock *lock,
-                               struct ldlm_extent *extent, int timeout)
-{
-
-       if (lock->l_flags & LDLM_FL_DESTROYED) /* lock already cancelled */
-               return 0;
-
-       /* XXX: never try to grab resource lock here because we're inside
-        * exp_bl_list_lock; in ldlm_lockd.c to handle waiting list we take
-        * res lock and then exp_bl_list_lock. */
-
-       if (!(lock->l_flags & LDLM_FL_AST_SENT))
-               /* ignore locks not being cancelled */
-               return 0;
-
-       LDLM_DEBUG(lock, "refreshed for req x"LPU64" ext("LPU64"->"LPU64") "
-                        "to %ds.\n", tgt_ses_req(tsi)->rq_xid, extent->start,
-                        extent->end, timeout);
-
-       /* OK. this is a possible lock the user holds doing I/O
-        * let's refresh eviction timer for it */
-       ldlm_refresh_waiting_lock(lock, timeout);
-       return 1;
+       req_timeout = req->rq_deadline - req->rq_arrival_time.tv_sec;
+       return max_t(time_t, at_est2timeout(at_get(&svcpt->scp_at_estimate)),
+                    req_timeout);
 }
 
-static int ofd_prolong_extent_locks(struct tgt_session_info *tsi,
-                                   __u64 start, __u64 end)
+/**
+ * Prolong lock timeout for the given extent.
+ *
+ * This function finds all locks related with incoming request and
+ * prolongs their timeout.
+ *
+ * If a client is holding a lock for a long time while it sends
+ * read or write RPCs to the OST for the object under this lock,
+ * then we don't want the OST to evict the client. Otherwise,
+ * if the network or disk is very busy then the client may not
+ * be able to make any progress to clear out dirty pages under
+ * the lock and the application will fail.
+ *
+ * Every time a Bulk Read/Write (BRW) request arrives for the object
+ * covered by the lock, extend the timeout on that lock. The RPC should
+ * contain a lock handle for the lock it is using, but this
+ * isn't handled correctly by all client versions, and the
+ * request may cover multiple locks.
+ *
+ * \param[in] tsi      target session environment for this request
+ * \param[in] data     struct of data to prolong locks
+ *
+ */
+static void ofd_prolong_extent_locks(struct tgt_session_info *tsi,
+                                   struct ldlm_prolong_args *data)
 {
-       struct obd_export       *exp = tsi->tsi_exp;
        struct obdo             *oa  = &tsi->tsi_ost_body->oa;
-       struct ldlm_extent       extent = {
-               .start = start,
-               .end = end
-       };
        struct ldlm_lock        *lock;
-       int                      timeout = prolong_timeout(tgt_ses_req(tsi));
-       int                      lock_count = 0;
 
        ENTRY;
 
+       data->lpa_timeout = prolong_timeout(tgt_ses_req(tsi));
+       data->lpa_export = tsi->tsi_exp;
+       data->lpa_resid = tsi->tsi_resid;
+
+       CDEBUG(D_RPCTRACE, "Prolong locks for req %p with x%llu"
+              " ext(%llu->%llu)\n", tgt_ses_req(tsi),
+              tgt_ses_req(tsi)->rq_xid, data->lpa_extent.start,
+              data->lpa_extent.end);
+
        if (oa->o_valid & OBD_MD_FLHANDLE) {
                /* mostly a request should be covered by only one lock, try
                 * fast path. */
@@ -1784,51 +2421,50 @@ static int ofd_prolong_extent_locks(struct tgt_session_info *tsi,
                if (lock != NULL) {
                        /* Fast path to check if the lock covers the whole IO
                         * region exclusively. */
-                       if (lock->l_granted_mode == LCK_PW &&
-                           ldlm_extent_contain(&lock->l_policy_data.l_extent,
-                                               &extent)) {
+                       if (ldlm_extent_contain(&lock->l_policy_data.l_extent,
+                                               &data->lpa_extent)) {
                                /* bingo */
-                               LASSERT(lock->l_export == exp);
-                               lock_count = ofd_prolong_one_lock(tsi, lock,
-                                                            &extent, timeout);
+                               LASSERT(lock->l_export == data->lpa_export);
+                               ldlm_lock_prolong_one(lock, data);
                                LDLM_LOCK_PUT(lock);
-                               RETURN(lock_count);
+                               RETURN_EXIT;
                        }
+                       lock->l_last_used = cfs_time_current();
                        LDLM_LOCK_PUT(lock);
                }
        }
 
-       spin_lock_bh(&exp->exp_bl_list_lock);
-       list_for_each_entry(lock, &exp->exp_bl_list, l_exp_list) {
-               LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
-               LASSERT(lock->l_resource->lr_type == LDLM_EXTENT);
-
-               if (!ldlm_res_eq(&tsi->tsi_resid, &lock->l_resource->lr_name))
-                       continue;
-
-               if (!ldlm_extent_overlap(&lock->l_policy_data.l_extent,
-                                        &extent))
-                       continue;
-
-               lock_count += ofd_prolong_one_lock(tsi, lock, &extent, timeout);
-       }
-       spin_unlock_bh(&exp->exp_bl_list_lock);
-
-       RETURN(lock_count);
+       ldlm_resource_prolong(data);
+       EXIT;
 }
 
 /**
- * Returns 1 if the given PTLRPC matches the given LDLM lock, or 0 if it does
- * not.
+ * Implementation of ptlrpc_hpreq_ops::hpreq_lock_match for OFD RW requests.
+ *
+ * Determine if \a lock and the lock from request \a req are equivalent
+ * by comparing their resource names, modes, and extents.
+ *
+ * It is used to give priority to read and write RPCs being done
+ * under this lock so that the client can drop the contended
+ * lock more quickly and let other clients use it. This improves
+ * overall performance in the case where the first client gets a
+ * very large lock extent that prevents other clients from
+ * submitting their writes.
+ *
+ * \param[in] req      ptlrpc_request being processed
+ * \param[in] lock     contended lock to match
+ *
+ * \retval             1 if lock is matched
+ * \retval             0 otherwise
  */
 static int ofd_rw_hpreq_lock_match(struct ptlrpc_request *req,
                                   struct ldlm_lock *lock)
 {
-       struct niobuf_remote    *rnb;
-       struct obd_ioobj        *ioo;
-       ldlm_mode_t              mode;
-       struct ldlm_extent       ext;
-       __u32                    opc = lustre_msg_get_opc(req->rq_reqmsg);
+       struct niobuf_remote *rnb;
+       struct obd_ioobj *ioo;
+       enum ldlm_mode  mode;
+       struct ldlm_extent ext;
+       __u32 opc = lustre_msg_get_opc(req->rq_reqmsg);
 
        ENTRY;
 
@@ -1838,16 +2474,21 @@ static int ofd_rw_hpreq_lock_match(struct ptlrpc_request *req,
        rnb = req_capsule_client_get(&req->rq_pill, &RMF_NIOBUF_REMOTE);
        LASSERT(rnb != NULL);
 
-       ext.start = rnb->offset;
+       ext.start = rnb->rnb_offset;
        rnb += ioo->ioo_bufcnt - 1;
-       ext.end = rnb->offset + rnb->len - 1;
+       ext.end = rnb->rnb_offset + rnb->rnb_len - 1;
 
        LASSERT(lock->l_resource != NULL);
        if (!ostid_res_name_eq(&ioo->ioo_oid, &lock->l_resource->lr_name))
                RETURN(0);
 
-       mode = LCK_PW;
+       /* a bulk write can only hold a reference on a PW extent lock
+        * or GROUP lock.
+        */
+       mode = LCK_PW | LCK_GROUP;
        if (opc == OST_READ)
+               /* whereas a bulk read can be protected by either a PR or PW
+                * extent lock */
                mode |= LCK_PR;
 
        if (!(lock->l_granted_mode & mode))
@@ -1857,92 +2498,153 @@ static int ofd_rw_hpreq_lock_match(struct ptlrpc_request *req,
 }
 
 /**
- * High-priority queue request check for whether the given PTLRPC request
- * (\a req) is blocking an LDLM lock cancel.
+ * Implementation of ptlrpc_hpreq_ops::hpreq_lock_check for OFD RW requests.
  *
- * Returns 1 if the given given PTLRPC request (\a req) is blocking an LDLM lock
- * cancel, 0 if it is not, and -EFAULT if the request is malformed.
+ * Check for whether the given PTLRPC request (\a req) is blocking
+ * an LDLM lock cancel. Also checks whether the request is covered by an LDLM
+ * lock.
  *
- * Only OST_READs, OST_WRITEs and OST_PUNCHes go on the h-p RPC queue.  This
- * function looks only at OST_READs and OST_WRITEs.
+ * \param[in] req      the incoming request
+ *
+ * \retval             1 if \a req is blocking an LDLM lock cancel
+ * \retval             0 if it is not
+ * \retval             -ESTALE if lock is not found
  */
 static int ofd_rw_hpreq_check(struct ptlrpc_request *req)
 {
        struct tgt_session_info *tsi;
        struct obd_ioobj        *ioo;
        struct niobuf_remote    *rnb;
-       __u64                    start, end;
-       int                      lock_count;
+       int opc;
+       struct ldlm_prolong_args pa = { 0 };
 
        ENTRY;
 
        /* Don't use tgt_ses_info() to get session info, because lock_match()
         * can be called while request has no processing thread yet. */
        tsi = lu_context_key_get(&req->rq_session, &tgt_session_key);
-       LASSERT(tsi != NULL);
 
        /*
         * Use LASSERT below because malformed RPCs should have
         * been filtered out in tgt_hpreq_handler().
         */
+       opc = lustre_msg_get_opc(req->rq_reqmsg);
+       LASSERT(opc == OST_READ || opc == OST_WRITE);
+
        ioo = req_capsule_client_get(&req->rq_pill, &RMF_OBD_IOOBJ);
        LASSERT(ioo != NULL);
 
        rnb = req_capsule_client_get(&req->rq_pill, &RMF_NIOBUF_REMOTE);
        LASSERT(rnb != NULL);
-       LASSERT(!(rnb->flags & OBD_BRW_SRVLOCK));
+       LASSERT(!(rnb->rnb_flags & OBD_BRW_SRVLOCK));
 
-       start = rnb->offset;
+       pa.lpa_mode = LCK_PW | LCK_GROUP;
+       if (opc == OST_READ)
+               pa.lpa_mode |= LCK_PR;
+
+       pa.lpa_extent.start = rnb->rnb_offset;
        rnb += ioo->ioo_bufcnt - 1;
-       end = rnb->offset + rnb->len - 1;
+       pa.lpa_extent.end = rnb->rnb_offset + rnb->rnb_len - 1;
 
        DEBUG_REQ(D_RPCTRACE, req, "%s %s: refresh rw locks: "DFID
-                                  " ("LPU64"->"LPU64")\n",
-                 tgt_name(tsi->tsi_tgt), current->comm,
-                 PFID(&tsi->tsi_fid), start, end);
+                 " (%llu->%llu)\n", tgt_name(tsi->tsi_tgt),
+                 current->comm, PFID(&tsi->tsi_fid), pa.lpa_extent.start,
+                 pa.lpa_extent.end);
 
-       lock_count = ofd_prolong_extent_locks(tsi, start, end);
+       ofd_prolong_extent_locks(tsi, &pa);
 
        CDEBUG(D_DLMTRACE, "%s: refreshed %u locks timeout for req %p.\n",
-              tgt_name(tsi->tsi_tgt), lock_count, req);
+              tgt_name(tsi->tsi_tgt), pa.lpa_blocks_cnt, req);
 
-       RETURN(lock_count > 0);
+       if (pa.lpa_blocks_cnt > 0)
+               RETURN(1);
+
+       RETURN(pa.lpa_locks_cnt > 0 ? 0 : -ESTALE);
 }
 
+/**
+ * Implementation of ptlrpc_hpreq_ops::hpreq_lock_fini for OFD RW requests.
+ *
+ * Called after the request has been handled. It refreshes lock timeout again
+ * so that client has more time to send lock cancel RPC.
+ *
+ * \param[in] req      request which is being processed.
+ */
 static void ofd_rw_hpreq_fini(struct ptlrpc_request *req)
 {
        ofd_rw_hpreq_check(req);
 }
 
 /**
- * Like tgt_rw_hpreq_lock_match(), but for OST_PUNCH RPCs.
+ * Implementation of ptlrpc_hpreq_ops::hpreq_lock_match for OST_PUNCH request.
+ *
+ * This function checks if the given lock is the same by its resname, mode
+ * and extent as one taken from the request.
+ * It is used to give priority to punch/truncate RPCs that might lead to
+ * the fastest release of that lock when a lock is contended.
+ *
+ * \param[in] req      ptlrpc_request being processed
+ * \param[in] lock     contended lock to match
+ *
+ * \retval             1 if lock is matched
+ * \retval             0 otherwise
  */
 static int ofd_punch_hpreq_lock_match(struct ptlrpc_request *req,
                                      struct ldlm_lock *lock)
 {
        struct tgt_session_info *tsi;
+       struct obdo             *oa;
+       struct ldlm_extent       ext;
+
+       ENTRY;
 
        /* Don't use tgt_ses_info() to get session info, because lock_match()
         * can be called while request has no processing thread yet. */
        tsi = lu_context_key_get(&req->rq_session, &tgt_session_key);
-       LASSERT(tsi != NULL);
 
+       /*
+        * Use LASSERT below because malformed RPCs should have
+        * been filtered out in tgt_hpreq_handler().
+        */
        LASSERT(tsi->tsi_ost_body != NULL);
        if (tsi->tsi_ost_body->oa.o_valid & OBD_MD_FLHANDLE &&
            tsi->tsi_ost_body->oa.o_handle.cookie == lock->l_handle.h_cookie)
-               return 1;
+               RETURN(1);
 
-       return 0;
+       oa = &tsi->tsi_ost_body->oa;
+       ext.start = oa->o_size;
+       ext.end   = oa->o_blocks;
+
+       LASSERT(lock->l_resource != NULL);
+       if (!ostid_res_name_eq(&oa->o_oi, &lock->l_resource->lr_name))
+               RETURN(0);
+
+       if (!(lock->l_granted_mode & (LCK_PW | LCK_GROUP)))
+               RETURN(0);
+
+       RETURN(ldlm_extent_overlap(&lock->l_policy_data.l_extent, &ext));
 }
 
 /**
- * Like ost_rw_hpreq_check(), but for OST_PUNCH RPCs.
+ * Implementation of ptlrpc_hpreq_ops::hpreq_lock_check for OST_PUNCH request.
+ *
+ * High-priority queue request check for whether the given punch request
+ * (\a req) is blocking an LDLM lock cancel. Also checks whether the request is
+ * covered by an LDLM lock.
+ *
+
+ *
+ * \param[in] req      the incoming request
+ *
+ * \retval             1 if \a req is blocking an LDLM lock cancel
+ * \retval             0 if it is not
+ * \retval             -ESTALE if lock is not found
  */
 static int ofd_punch_hpreq_check(struct ptlrpc_request *req)
 {
        struct tgt_session_info *tsi;
        struct obdo             *oa;
-       int                      lock_count;
+       struct ldlm_prolong_args pa = { 0 };
 
        ENTRY;
 
@@ -1955,37 +2657,60 @@ static int ofd_punch_hpreq_check(struct ptlrpc_request *req)
        LASSERT(!(oa->o_valid & OBD_MD_FLFLAGS &&
                  oa->o_flags & OBD_FL_SRVLOCK));
 
+       pa.lpa_mode = LCK_PW | LCK_GROUP;
+       pa.lpa_extent.start = oa->o_size;
+       pa.lpa_extent.end   = oa->o_blocks;
+
        CDEBUG(D_DLMTRACE,
-              "%s: refresh locks: "LPU64"/"LPU64" ("LPU64"->"LPU64")\n",
+              "%s: refresh locks: %llu/%llu (%llu->%llu)\n",
               tgt_name(tsi->tsi_tgt), tsi->tsi_resid.name[0],
-              tsi->tsi_resid.name[1], oa->o_size, oa->o_blocks);
+              tsi->tsi_resid.name[1], pa.lpa_extent.start, pa.lpa_extent.end);
 
-       lock_count = ofd_prolong_extent_locks(tsi, oa->o_size, oa->o_blocks);
+       ofd_prolong_extent_locks(tsi, &pa);
 
        CDEBUG(D_DLMTRACE, "%s: refreshed %u locks timeout for req %p.\n",
-              tgt_name(tsi->tsi_tgt), lock_count, req);
+              tgt_name(tsi->tsi_tgt), pa.lpa_blocks_cnt, req);
 
-       RETURN(lock_count > 0);
+       if (pa.lpa_blocks_cnt > 0)
+               RETURN(1);
+
+       RETURN(pa.lpa_locks_cnt > 0 ? 0 : -ESTALE);
 }
 
+/**
+ * Implementation of ptlrpc_hpreq_ops::hpreq_lock_fini for OST_PUNCH request.
+ *
+ * Called after the request has been handled. It refreshes lock timeout again
+ * so that client has more time to send lock cancel RPC.
+ *
+ * \param[in] req      request which is being processed.
+ */
 static void ofd_punch_hpreq_fini(struct ptlrpc_request *req)
 {
        ofd_punch_hpreq_check(req);
 }
 
-struct ptlrpc_hpreq_ops ofd_hpreq_rw = {
+static struct ptlrpc_hpreq_ops ofd_hpreq_rw = {
        .hpreq_lock_match       = ofd_rw_hpreq_lock_match,
        .hpreq_check            = ofd_rw_hpreq_check,
        .hpreq_fini             = ofd_rw_hpreq_fini
 };
 
-struct ptlrpc_hpreq_ops ofd_hpreq_punch = {
+static struct ptlrpc_hpreq_ops ofd_hpreq_punch = {
        .hpreq_lock_match       = ofd_punch_hpreq_lock_match,
        .hpreq_check            = ofd_punch_hpreq_check,
        .hpreq_fini             = ofd_punch_hpreq_fini
 };
 
-/** Assign high priority operations to the IO requests */
+/**
+ * Assign high priority operations to an IO request.
+ *
+ * Check if the incoming request is a candidate for
+ * high-priority processing. If it is, assign it a high
+ * priority operations table.
+ *
+ * \param[in] tsi      target session environment for this request
+ */
 static void ofd_hp_brw(struct tgt_session_info *tsi)
 {
        struct niobuf_remote    *rnb;
@@ -2000,18 +2725,31 @@ static void ofd_hp_brw(struct tgt_session_info *tsi)
                LASSERT(rnb != NULL); /* must exist after request preprocessing */
 
                /* no high priority if server lock is needed */
-               if (rnb->flags & OBD_BRW_SRVLOCK)
+               if (rnb->rnb_flags & OBD_BRW_SRVLOCK ||
+                   (lustre_msg_get_flags(tgt_ses_req(tsi)->rq_reqmsg)
+                    & MSG_REPLAY))
                        return;
        }
        tgt_ses_req(tsi)->rq_ops = &ofd_hpreq_rw;
 }
 
+/**
+ * Assign high priority operations to an punch request.
+ *
+ * Check if the incoming request is a candidate for
+ * high-priority processing. If it is, assign it a high
+ * priority operations table.
+ *
+ * \param[in] tsi      target session environment for this request
+ */
 static void ofd_hp_punch(struct tgt_session_info *tsi)
 {
        LASSERT(tsi->tsi_ost_body != NULL); /* must exists if we are here */
        /* no high-priority if server lock is needed */
-       if (tsi->tsi_ost_body->oa.o_valid & OBD_MD_FLFLAGS &&
-           tsi->tsi_ost_body->oa.o_flags & OBD_FL_SRVLOCK)
+       if ((tsi->tsi_ost_body->oa.o_valid & OBD_MD_FLFLAGS &&
+            tsi->tsi_ost_body->oa.o_flags & OBD_FL_SRVLOCK) ||
+           tgt_conn_flags(tsi) & OBD_CONNECT_MDS ||
+           lustre_msg_get_flags(tgt_ses_req(tsi)->rq_reqmsg) & MSG_REPLAY)
                return;
        tgt_ses_req(tsi)->rq_ops = &ofd_hpreq_punch;
 }
@@ -2021,6 +2759,14 @@ static void ofd_hp_punch(struct tgt_session_info *tsi)
 #define OST_BRW_READ   OST_READ
 #define OST_BRW_WRITE  OST_WRITE
 
+/**
+ * Table of OFD-specific request handlers
+ *
+ * This table contains all opcodes accepted by OFD and
+ * specifies handlers for them. The tgt_request_handler()
+ * uses such table from each target to process incoming
+ * requests.
+ */
 static struct tgt_handler ofd_tgt_handlers[] = {
 TGT_RPC_HANDLER(OST_FIRST_OPC,
                0,                      OST_CONNECT,    tgt_connect,
@@ -2051,6 +2797,7 @@ TGT_OST_HDL_HP(HABEO_CORPUS| HABEO_REFERO | MUTABOR,
                                                        ofd_hp_punch),
 TGT_OST_HDL(HABEO_CORPUS| HABEO_REFERO,        OST_SYNC,       ofd_sync_hdl),
 TGT_OST_HDL(0          | HABEO_REFERO, OST_QUOTACTL,   ofd_quotactl),
+TGT_OST_HDL(HABEO_CORPUS | HABEO_REFERO, OST_LADVISE,  ofd_ladvise_hdl),
 };
 
 static struct tgt_opc_slice ofd_common_slice[] = {
@@ -2085,18 +2832,78 @@ static struct tgt_opc_slice ofd_common_slice[] = {
                .tos_hs         = tgt_lfsck_handlers
        },
        {
+               .tos_opc_start  = SEC_FIRST_OPC,
+               .tos_opc_end    = SEC_LAST_OPC,
+               .tos_hs         = tgt_sec_ctx_handlers
+       },
+       {
                .tos_hs         = NULL
        }
 };
 
+/* context key constructor/destructor: ofd_key_init(), ofd_key_fini() */
+LU_KEY_INIT_FINI(ofd, struct ofd_thread_info);
+
+/**
+ * Implementation of lu_context_key::lct_key_exit.
+ *
+ * Optional method called on lu_context_exit() for all allocated
+ * keys.
+ * It is used in OFD to sanitize context values which may be re-used
+ * during another request processing by the same thread.
+ *
+ * \param[in] ctx      execution context
+ * \param[in] key      context key
+ * \param[in] data     ofd_thread_info
+ */
+static void ofd_key_exit(const struct lu_context *ctx,
+                        struct lu_context_key *key, void *data)
+{
+       struct ofd_thread_info *info = data;
+
+       info->fti_env = NULL;
+       info->fti_exp = NULL;
+
+       info->fti_xid = 0;
+       info->fti_pre_version = 0;
+
+       memset(&info->fti_attr, 0, sizeof info->fti_attr);
+}
+
+struct lu_context_key ofd_thread_key = {
+       .lct_tags = LCT_DT_THREAD,
+       .lct_init = ofd_key_init,
+       .lct_fini = ofd_key_fini,
+       .lct_exit = ofd_key_exit
+};
+
+/**
+ * Initialize OFD device according to parameters in the config log \a cfg.
+ *
+ * This is the main starting point of OFD initialization. It fills all OFD
+ * parameters with their initial values and calls other initializing functions
+ * to set up all OFD subsystems.
+ *
+ * \param[in] env      execution environment
+ * \param[in] m                OFD device
+ * \param[in] ldt      LU device type of OFD
+ * \param[in] cfg      configuration log
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
 static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
                     struct lu_device_type *ldt, struct lustre_cfg *cfg)
 {
-       const char              *dev = lustre_cfg_string(cfg, 0);
-       struct ofd_thread_info  *info = NULL;
-       struct obd_device       *obd;
-       struct obd_statfs       *osfs;
-       int                      rc;
+       const char *dev = lustre_cfg_string(cfg, 0);
+       struct ofd_thread_info *info = NULL;
+       struct obd_device *obd;
+       struct tg_grants_data *tgd = &m->ofd_lut.lut_tgd;
+       struct obd_statfs *osfs;
+       struct lu_fid fid;
+       struct nm_config_file *nodemap_config;
+       struct obd_device_target *obt;
+       int rc;
 
        ENTRY;
 
@@ -2110,7 +2917,8 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
        if (rc != 0)
                RETURN(rc);
 
-       obd->u.obt.obt_magic = OBT_MAGIC;
+       obt = &obd->u.obt;
+       obt->obt_magic = OBT_MAGIC;
 
        m->ofd_fmd_max_num = OFD_FMD_MAX_NUM_DEFAULT;
        m->ofd_fmd_max_age = OFD_FMD_MAX_AGE_DEFAULT;
@@ -2119,21 +2927,22 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
        m->ofd_raid_degraded = 0;
        m->ofd_syncjournal = 0;
        ofd_slc_set(m);
-       m->ofd_grant_compat_disable = 0;
+       tgd->tgd_grant_compat_disable = 0;
        m->ofd_soft_sync_limit = OFD_SOFT_SYNC_LIMIT_DEFAULT;
 
        /* statfs data */
-       spin_lock_init(&m->ofd_osfs_lock);
-       m->ofd_osfs_age = cfs_time_shift_64(-1000);
-       m->ofd_osfs_unstable = 0;
-       m->ofd_statfs_inflight = 0;
-       m->ofd_osfs_inflight = 0;
+       spin_lock_init(&tgd->tgd_osfs_lock);
+       tgd->tgd_osfs_age = cfs_time_shift_64(-1000);
+       tgd->tgd_osfs_unstable = 0;
+       tgd->tgd_statfs_inflight = 0;
+       tgd->tgd_osfs_inflight = 0;
 
        /* grant data */
-       spin_lock_init(&m->ofd_grant_lock);
-       m->ofd_tot_dirty = 0;
-       m->ofd_tot_granted = 0;
-       m->ofd_tot_pending = 0;
+       spin_lock_init(&tgd->tgd_grant_lock);
+       tgd->tgd_tot_dirty = 0;
+       tgd->tgd_tot_granted = 0;
+       tgd->tgd_tot_pending = 0;
+
        m->ofd_seq_count = 0;
        init_waitqueue_head(&m->ofd_inconsistency_thread.t_ctl_waitq);
        INIT_LIST_HEAD(&m->ofd_inconsistency_list);
@@ -2142,12 +2951,6 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
        spin_lock_init(&m->ofd_batch_lock);
        init_rwsem(&m->ofd_lastid_rwsem);
 
-       obd->u.filter.fo_fl_oss_capa = 0;
-       CFS_INIT_LIST_HEAD(&obd->u.filter.fo_capa_keys);
-       obd->u.filter.fo_capa_hash = init_capa_hash();
-       if (obd->u.filter.fo_capa_hash == NULL)
-               RETURN(-ENOMEM);
-
        m->ofd_dt_dev.dd_lu_dev.ld_ops = &ofd_lu_ops;
        m->ofd_dt_dev.dd_lu_dev.ld_obd = obd;
        /* set this lu_device to obd, because error handling need it */
@@ -2175,7 +2978,7 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
 
        info = ofd_info_init(env, NULL);
        if (info == NULL)
-               RETURN(-EFAULT);
+               GOTO(err_fini_proc, rc = -EFAULT);
 
        rc = ofd_stack_init(env, m, cfg);
        if (rc) {
@@ -2185,24 +2988,6 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
 
        ofd_procfs_add_brw_stats_symlink(m);
 
-       /* populate cached statfs data */
-       osfs = &ofd_info(env)->fti_u.osfs;
-       rc = ofd_statfs_internal(env, m, osfs, 0, NULL);
-       if (rc != 0) {
-               CERROR("%s: can't get statfs data, rc %d\n", obd->obd_name, rc);
-               GOTO(err_fini_stack, rc);
-       }
-       if (!IS_PO2(osfs->os_bsize)) {
-               CERROR("%s: blocksize (%d) is not a power of 2\n",
-                               obd->obd_name, osfs->os_bsize);
-               GOTO(err_fini_stack, rc = -EPROTO);
-       }
-       m->ofd_blockbits = fls(osfs->os_bsize) - 1;
-
-       m->ofd_precreate_batch = OFD_PRECREATE_BATCH_DEFAULT;
-       if (osfs->os_bsize * osfs->os_blocks < OFD_PRECREATE_SMALL_FS)
-               m->ofd_precreate_batch = OFD_PRECREATE_BATCH_SMALL;
-
        snprintf(info->fti_u.name, sizeof(info->fti_u.name), "%s-%s",
                 "filter"/*LUSTRE_OST_NAME*/, obd->obd_uuid.uuid);
        m->ofd_namespace = ldlm_namespace_new(obd, info->fti_u.name,
@@ -2220,15 +3005,7 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
        ptlrpc_init_client(LDLM_CB_REQUEST_PORTAL, LDLM_CB_REPLY_PORTAL,
                           "filter_ldlm_cb_client", &obd->obd_ldlm_client);
 
-       dt_conf_get(env, m->ofd_osd, &m->ofd_dt_conf);
-
-       /* Allow at most ddp_grant_reserved% of the available filesystem space
-        * to be granted to clients, so that any errors in the grant overhead
-        * calculations do not allow granting more space to clients than can be
-        * written. Assumes that in aggregate the grant overhead calculations do
-        * not have more than ddp_grant_reserved% estimation error in them. */
-       m->ofd_grant_ratio =
-               ofd_grant_ratio_conv(m->ofd_dt_conf.ddp_grant_reserved);
+       dt_conf_get(env, m->ofd_osd, &m->ofd_lut.lut_dt_conf);
 
        rc = tgt_init(env, &m->ofd_lut, obd, m->ofd_osd, ofd_common_slice,
                      OBD_FAIL_OST_ALL_REQUEST_NET,
@@ -2236,22 +3013,72 @@ static int ofd_init0(const struct lu_env *env, struct ofd_device *m,
        if (rc)
                GOTO(err_free_ns, rc);
 
+       /* populate cached statfs data */
+       osfs = &ofd_info(env)->fti_u.osfs;
+       rc = tgt_statfs_internal(env, &m->ofd_lut, osfs, 0, NULL);
+       if (rc != 0) {
+               CERROR("%s: can't get statfs data, rc %d\n", obd->obd_name, rc);
+               GOTO(err_fini_lut, rc);
+       }
+       if (!is_power_of_2(osfs->os_bsize)) {
+               CERROR("%s: blocksize (%d) is not a power of 2\n",
+                       obd->obd_name, osfs->os_bsize);
+               GOTO(err_fini_lut, rc = -EPROTO);
+       }
+       tgd->tgd_blockbits = fls(osfs->os_bsize) - 1;
+
+       if (DT_DEF_BRW_SIZE < (1U << tgd->tgd_blockbits))
+               m->ofd_brw_size = 1U << tgd->tgd_blockbits;
+       else
+               m->ofd_brw_size = DT_DEF_BRW_SIZE;
+
+       m->ofd_cksum_types_supported = cksum_types_supported_server();
+       m->ofd_precreate_batch = OFD_PRECREATE_BATCH_DEFAULT;
+       if (osfs->os_bsize * osfs->os_blocks < OFD_PRECREATE_SMALL_FS)
+               m->ofd_precreate_batch = OFD_PRECREATE_BATCH_SMALL;
+
        rc = ofd_fs_setup(env, m, obd);
        if (rc)
                GOTO(err_fini_lut, rc);
 
-       rc = ofd_start_inconsistency_verification_thread(m);
+       fid.f_seq = FID_SEQ_LOCAL_NAME;
+       fid.f_oid = 1;
+       fid.f_ver = 0;
+       rc = local_oid_storage_init(env, m->ofd_osd, &fid,
+                                   &m->ofd_los);
        if (rc != 0)
                GOTO(err_fini_fs, rc);
 
+       nodemap_config = nm_config_file_register_tgt(env, m->ofd_osd,
+                                                    m->ofd_los);
+       if (IS_ERR(nodemap_config)) {
+               rc = PTR_ERR(nodemap_config);
+               if (rc != -EROFS)
+                       GOTO(err_fini_los, rc);
+       } else {
+               obt->obt_nodemap_config_file = nodemap_config;
+       }
+
+       rc = ofd_start_inconsistency_verification_thread(m);
+       if (rc != 0)
+               GOTO(err_fini_nm, rc);
+
+       tgt_adapt_sptlrpc_conf(&m->ofd_lut);
+
        RETURN(0);
 
+err_fini_nm:
+       nm_config_file_deregister_tgt(env, obt->obt_nodemap_config_file);
+       obt->obt_nodemap_config_file = NULL;
+err_fini_los:
+       local_oid_storage_fini(env, m->ofd_los);
+       m->ofd_los = NULL;
 err_fini_fs:
        ofd_fs_cleanup(env, m);
 err_fini_lut:
        tgt_fini(env, &m->ofd_lut);
 err_free_ns:
-       ldlm_namespace_free(m->ofd_namespace, 0, obd->obd_force);
+       ldlm_namespace_free(m->ofd_namespace, NULL, obd->obd_force);
        obd->obd_namespace = m->ofd_namespace = NULL;
 err_fini_stack:
        ofd_stack_fini(env, m, &m->ofd_osd->dd_lu_dev);
@@ -2260,6 +3087,15 @@ err_fini_proc:
        return rc;
 }
 
+/**
+ * Stop the OFD device
+ *
+ * This function stops the OFD device and all its subsystems.
+ * This is the end of OFD lifecycle.
+ *
+ * \param[in] env      execution environment
+ * \param[in] m                OFD device
+ */
 static void ofd_fini(const struct lu_env *env, struct ofd_device *m)
 {
        struct obd_device       *obd = ofd_obd(m);
@@ -2270,6 +3106,10 @@ static void ofd_fini(const struct lu_env *env, struct ofd_device *m)
        stop.ls_flags = 0;
        lfsck_stop(env, m->ofd_osd, &stop);
        target_recovery_fini(obd);
+       if (m->ofd_namespace != NULL)
+               ldlm_namespace_free_prior(m->ofd_namespace, NULL,
+                                         d->ld_obd->obd_force);
+
        obd_exports_barrier(obd);
        obd_zombie_barrier();
 
@@ -2277,13 +3117,16 @@ static void ofd_fini(const struct lu_env *env, struct ofd_device *m)
        ofd_stop_inconsistency_verification_thread(m);
        lfsck_degister(env, m->ofd_osd);
        ofd_fs_cleanup(env, m);
+       nm_config_file_deregister_tgt(env, obd->u.obt.obt_nodemap_config_file);
+       obd->u.obt.obt_nodemap_config_file = NULL;
 
-       ofd_free_capa_keys(m);
-       cleanup_capa_hash(obd->u.filter.fo_capa_hash);
+       if (m->ofd_los != NULL) {
+               local_oid_storage_fini(env, m->ofd_los);
+               m->ofd_los = NULL;
+       }
 
        if (m->ofd_namespace != NULL) {
-               ldlm_namespace_free(m->ofd_namespace, NULL,
-                                   d->ld_obd->obd_force);
+               ldlm_namespace_free_post(m->ofd_namespace);
                d->ld_obd->obd_namespace = m->ofd_namespace = NULL;
        }
 
@@ -2294,6 +3137,17 @@ static void ofd_fini(const struct lu_env *env, struct ofd_device *m)
        EXIT;
 }
 
+/**
+ * Implementation of lu_device_type_operations::ldto_device_fini.
+ *
+ * Finalize device. Dual to ofd_device_init(). It is called from
+ * obd_precleanup() and stops the current device.
+ *
+ * \param[in] env      execution environment
+ * \param[in] d                LU device of OFD
+ *
+ * \retval             NULL
+ */
 static struct lu_device *ofd_device_fini(const struct lu_env *env,
                                         struct lu_device *d)
 {
@@ -2302,6 +3156,16 @@ static struct lu_device *ofd_device_fini(const struct lu_env *env,
        RETURN(NULL);
 }
 
+/**
+ * Implementation of lu_device_type_operations::ldto_device_free.
+ *
+ * Free OFD device. Dual to ofd_device_alloc().
+ *
+ * \param[in] env      execution environment
+ * \param[in] d                LU device of OFD
+ *
+ * \retval             NULL
+ */
 static struct lu_device *ofd_device_free(const struct lu_env *env,
                                         struct lu_device *d)
 {
@@ -2312,6 +3176,19 @@ static struct lu_device *ofd_device_free(const struct lu_env *env,
        RETURN(NULL);
 }
 
+/**
+ * Implementation of lu_device_type_operations::ldto_device_alloc.
+ *
+ * This function allocates the new OFD device. It is called from
+ * obd_setup() if OBD device had lu_device_type defined.
+ *
+ * \param[in] env      execution environment
+ * \param[in] t                lu_device_type of OFD device
+ * \param[in] cfg      configuration log
+ *
+ * \retval             pointer to the lu_device of just allocated OFD
+ * \retval             ERR_PTR of return value on error
+ */
 static struct lu_device *ofd_device_alloc(const struct lu_env *env,
                                          struct lu_device_type *t,
                                          struct lustre_cfg *cfg)
@@ -2335,32 +3212,7 @@ static struct lu_device *ofd_device_alloc(const struct lu_env *env,
        return l;
 }
 
-/* thread context key constructor/destructor */
-LU_KEY_INIT_FINI(ofd, struct ofd_thread_info);
-
-static void ofd_key_exit(const struct lu_context *ctx,
-                        struct lu_context_key *key, void *data)
-{
-       struct ofd_thread_info *info = data;
-
-       info->fti_env = NULL;
-       info->fti_exp = NULL;
-
-       info->fti_xid = 0;
-       info->fti_pre_version = 0;
-       info->fti_used = 0;
-
-       memset(&info->fti_attr, 0, sizeof info->fti_attr);
-}
-
-struct lu_context_key ofd_thread_key = {
-       .lct_tags = LCT_DT_THREAD,
-       .lct_init = ofd_key_init,
-       .lct_fini = ofd_key_fini,
-       .lct_exit = ofd_key_exit
-};
-
-/* type constructor/destructor: mdt_type_init, mdt_type_fini */
+/* type constructor/destructor: ofd_type_init(), ofd_type_fini() */
 LU_TYPE_INIT_FINI(ofd, &ofd_thread_key);
 
 static struct lu_device_type_operations ofd_device_type_ops = {
@@ -2382,9 +3234,17 @@ static struct lu_device_type ofd_device_type = {
        .ldt_ctx_tags   = LCT_DT_THREAD
 };
 
-int __init ofd_init(void)
+/**
+ * Initialize OFD module.
+ *
+ * This function is called upon module loading. It registers OFD device type
+ * and prepares all in-memory structures used by all OFD devices.
+ *
+ * \retval             0 if successful
+ * \retval             negative value on error
+ */
+static int __init ofd_init(void)
 {
-       struct lprocfs_static_vars      lvars;
        int                             rc;
 
        rc = lu_kmem_init(ofd_caches);
@@ -2397,25 +3257,27 @@ int __init ofd_init(void)
                return(rc);
        }
 
-       lprocfs_ofd_init_vars(&lvars);
-
        rc = class_register_type(&ofd_obd_ops, NULL, true, NULL,
-#ifndef HAVE_ONLY_PROCFS_SEQ
-                                lvars.module_vars,
-#endif
                                 LUSTRE_OST_NAME, &ofd_device_type);
        return rc;
 }
 
-void __exit ofd_exit(void)
+/**
+ * Stop OFD module.
+ *
+ * This function is called upon OFD module unloading.
+ * It frees all related structures and unregisters OFD device type.
+ */
+static void __exit ofd_exit(void)
 {
        ofd_fmd_exit();
        lu_kmem_fini(ofd_caches);
        class_unregister_type(LUSTRE_OST_NAME);
 }
 
-MODULE_AUTHOR("Whamcloud, Inc. <http://www.whamcloud.com/>");
+MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
 MODULE_DESCRIPTION("Lustre Object Filtering Device");
+MODULE_VERSION(LUSTRE_VERSION_STRING);
 MODULE_LICENSE("GPL");
 
 module_init(ofd_init);