drivers/staging/lustre/lustre/fld/fld_handler.c - kernel/msm-4.9 - Gitiles

 /*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 only,
  * as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License version 2 for more details (a copy is included
  * in the LICENSE file that accompanied this code).
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  *
  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  * GPL HEADER END
  */
 /*
  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
  * Copyright (c) 2011, 2013, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
  * lustre/fld/fld_handler.c
  *
  * FLD (Fids Location Database)
  *
  * Author: Yury Umanets <umka@clusterfs.com>
  * Author: WangDi <wangdi@clusterfs.com>
  * Author: Pravin Shelar <pravin.shelar@sun.com>
  */

 #define DEBUG_SUBSYSTEM S_FLD

 # include <linux/libcfs/libcfs.h>
 # include <linux/module.h>
 # include <linux/jbd.h>
 # include <asm/div64.h>

 #include <obd.h>
 #include <obd_class.h>
 #include <lustre_ver.h>
 #include <obd_support.h>
 #include <lprocfs_status.h>

 #include <md_object.h>
 #include <lustre_fid.h>
 #include <lustre_req_layout.h>
 #include "fld_internal.h"
 #include <lustre_fid.h>


 /* context key constructor/destructor: fld_key_init, fld_key_fini */
 LU_KEY_INIT_FINI(fld, struct fld_thread_info);

 /* context key: fld_thread_key */
 LU_CONTEXT_KEY_DEFINE(fld, LCT_MD_THREAD | LCT_DT_THREAD | LCT_MG_THREAD);

 proc_dir_entry_t *fld_type_proc_dir = NULL;

 static int __init fld_mod_init(void)
 {
 	fld_type_proc_dir = lprocfs_register(LUSTRE_FLD_NAME,
 					     proc_lustre_root,
 					     NULL, NULL);
 	if (IS_ERR(fld_type_proc_dir))
 		return PTR_ERR(fld_type_proc_dir);

 	LU_CONTEXT_KEY_INIT(&fld_thread_key);
 	lu_context_key_register(&fld_thread_key);
 	return 0;
 }

 static void __exit fld_mod_exit(void)
 {
 	lu_context_key_degister(&fld_thread_key);
 	if (fld_type_proc_dir != NULL && !IS_ERR(fld_type_proc_dir)) {
 		lprocfs_remove(&fld_type_proc_dir);
 		fld_type_proc_dir = NULL;
 	}
 }

 int fld_declare_server_create(const struct lu_env *env,
 			      struct lu_server_fld *fld,
 			      struct lu_seq_range *range,
 			      struct thandle *th)
 {
 	int rc;

 	rc = fld_declare_index_create(env, fld, range, th);
 	RETURN(rc);
 }
 EXPORT_SYMBOL(fld_declare_server_create);

 /**
  * Insert FLD index entry and update FLD cache.
  *
  * This function is called from the sequence allocator when a super-sequence
  * is granted to a server.
  */
 int fld_server_create(const struct lu_env *env, struct lu_server_fld *fld,
 		      struct lu_seq_range *range, struct thandle *th)
 {
 	int rc;

 	mutex_lock(&fld->lsf_lock);
 	rc = fld_index_create(env, fld, range, th);
 	mutex_unlock(&fld->lsf_lock);

 	RETURN(rc);
 }
 EXPORT_SYMBOL(fld_server_create);

 /**
  *  Lookup mds by seq, returns a range for given seq.
  *
  *  If that entry is not cached in fld cache, request is sent to super
  *  sequence controller node (MDT0). All other MDT[1...N] and client
  *  cache fld entries, but this cache is not persistent.
  */
 int fld_server_lookup(const struct lu_env *env, struct lu_server_fld *fld,
 		      seqno_t seq, struct lu_seq_range *range)
 {
 	struct lu_seq_range *erange;
 	struct fld_thread_info *info;
 	int rc;
 	ENTRY;

 	info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
 	LASSERT(info != NULL);
 	erange = &info->fti_lrange;

 	/* Lookup it in the cache. */
 	rc = fld_cache_lookup(fld->lsf_cache, seq, erange);
 	if (rc == 0) {
 		if (unlikely(fld_range_type(erange) != fld_range_type(range) &&
 			     !fld_range_is_any(range))) {
 			CERROR("%s: FLD cache range "DRANGE" does not match"
 			       "requested flag %x: rc = %d\n", fld->lsf_name,
 			       PRANGE(erange), range->lsr_flags, -EIO);
 			RETURN(-EIO);
 		}
 		*range = *erange;
 		RETURN(0);
 	}

 	if (fld->lsf_obj) {
 		/* On server side, all entries should be in cache.
 		 * If we can not find it in cache, just return error */
 		CERROR("%s: Cannot find sequence "LPX64": rc = %d\n",
 			fld->lsf_name, seq, -EIO);
 		RETURN(-EIO);
 	} else {
 		LASSERT(fld->lsf_control_exp);
 		/* send request to mdt0 i.e. super seq. controller.
 		 * This is temporary solution, long term solution is fld
 		 * replication on all mdt servers.
 		 */
 		range->lsr_start = seq;
 		rc = fld_client_rpc(fld->lsf_control_exp,
 				    range, FLD_LOOKUP);
 		if (rc == 0)
 			fld_cache_insert(fld->lsf_cache, range);
 	}
 	RETURN(rc);
 }
 EXPORT_SYMBOL(fld_server_lookup);

 /**
  * All MDT server handle fld lookup operation. But only MDT0 has fld index.
  * if entry is not found in cache we need to forward lookup request to MDT0
  */

 static int fld_server_handle(struct lu_server_fld *fld,
 			     const struct lu_env *env,
 			     __u32 opc, struct lu_seq_range *range,
 			     struct fld_thread_info *info)
 {
 	int rc;
 	ENTRY;

 	switch (opc) {
 	case FLD_LOOKUP:
 		rc = fld_server_lookup(env, fld, range->lsr_start, range);
 		break;
 	default:
 		rc = -EINVAL;
 		break;
 	}

 	CDEBUG(D_INFO, "%s: FLD req handle: error %d (opc: %d, range: "
 	       DRANGE"\n", fld->lsf_name, rc, opc, PRANGE(range));

 	RETURN(rc);

 }

 static int fld_req_handle(struct ptlrpc_request *req,
 			  struct fld_thread_info *info)
 {
 	struct obd_export *exp = req->rq_export;
 	struct lu_site *site = exp->exp_obd->obd_lu_dev->ld_site;
 	struct lu_seq_range *in;
 	struct lu_seq_range *out;
 	int rc;
 	__u32 *opc;
 	ENTRY;

 	rc = req_capsule_server_pack(info->fti_pill);
 	if (rc)
 		RETURN(err_serious(rc));

 	opc = req_capsule_client_get(info->fti_pill, &RMF_FLD_OPC);
 	if (opc != NULL) {
 		in = req_capsule_client_get(info->fti_pill, &RMF_FLD_MDFLD);
 		if (in == NULL)
 			RETURN(err_serious(-EPROTO));
 		out = req_capsule_server_get(info->fti_pill, &RMF_FLD_MDFLD);
 		if (out == NULL)
 			RETURN(err_serious(-EPROTO));
 		*out = *in;

 		/* For old 2.0 client, the 'lsr_flags' is uninitialized.
 		 * Set it as 'LU_SEQ_RANGE_MDT' by default. */
 		if (!(exp_connect_flags(exp) & OBD_CONNECT_64BITHASH) &&
 		    !(exp_connect_flags(exp) & OBD_CONNECT_MDS_MDS) &&
 		    !(exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT) &&
 		    !exp->exp_libclient)
 			fld_range_set_mdt(out);

 		rc = fld_server_handle(lu_site2seq(site)->ss_server_fld,
 				       req->rq_svc_thread->t_env,
 				       *opc, out, info);
 	} else {
 		rc = err_serious(-EPROTO);
 	}

 	RETURN(rc);
 }

 static void fld_thread_info_init(struct ptlrpc_request *req,
 				 struct fld_thread_info *info)
 {
 	info->fti_pill = &req->rq_pill;
 	/* Init request capsule. */
 	req_capsule_init(info->fti_pill, req, RCL_SERVER);
 	req_capsule_set(info->fti_pill, &RQF_FLD_QUERY);
 }

 static void fld_thread_info_fini(struct fld_thread_info *info)
 {
 	req_capsule_fini(info->fti_pill);
 }

 static int fld_handle(struct ptlrpc_request *req)
 {
 	struct fld_thread_info *info;
 	const struct lu_env *env;
 	int rc;

 	env = req->rq_svc_thread->t_env;
 	LASSERT(env != NULL);

 	info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
 	LASSERT(info != NULL);

 	fld_thread_info_init(req, info);
 	rc = fld_req_handle(req, info);
 	fld_thread_info_fini(info);

 	return rc;
 }

 /*
  * Entry point for handling FLD RPCs called from MDT.
  */
 int fld_query(struct com_thread_info *info)
 {
 	return fld_handle(info->cti_pill->rc_req);
 }
 EXPORT_SYMBOL(fld_query);

 /*
  * Returns true, if fid is local to this server node.
  *
  * WARNING: this function is *not* guaranteed to return false if fid is
  * remote: it makes an educated conservative guess only.
  *
  * fid_is_local() is supposed to be used in assertion checks only.
  */
 int fid_is_local(const struct lu_env *env,
 		 struct lu_site *site, const struct lu_fid *fid)
 {
 	int result;
 	struct seq_server_site *ss_site;
 	struct lu_seq_range *range;
 	struct fld_thread_info *info;
 	ENTRY;

 	info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
 	range = &info->fti_lrange;

 	result = 1; /* conservatively assume fid is local */
 	ss_site = lu_site2seq(site);
 	if (ss_site->ss_client_fld != NULL) {
 		int rc;

 		rc = fld_cache_lookup(ss_site->ss_client_fld->lcf_cache,
 				      fid_seq(fid), range);
 		if (rc == 0)
 			result = (range->lsr_index == ss_site->ss_node_id);
 	}
 	return result;
 }
 EXPORT_SYMBOL(fid_is_local);

 static void fld_server_proc_fini(struct lu_server_fld *fld);

 #ifdef LPROCFS
 static int fld_server_proc_init(struct lu_server_fld *fld)
 {
 	int rc = 0;
 	ENTRY;

 	fld->lsf_proc_dir = lprocfs_register(fld->lsf_name,
 					     fld_type_proc_dir,
 					     fld_server_proc_list, fld);
 	if (IS_ERR(fld->lsf_proc_dir)) {
 		rc = PTR_ERR(fld->lsf_proc_dir);
 		RETURN(rc);
 	}

 	rc = lprocfs_seq_create(fld->lsf_proc_dir, "fldb", 0444,
 				&fld_proc_seq_fops, fld);
 	if (rc) {
 		lprocfs_remove(&fld->lsf_proc_dir);
 		fld->lsf_proc_dir = NULL;
 	}

 	RETURN(rc);
 }

 static void fld_server_proc_fini(struct lu_server_fld *fld)
 {
 	ENTRY;
 	if (fld->lsf_proc_dir != NULL) {
 		if (!IS_ERR(fld->lsf_proc_dir))
 			lprocfs_remove(&fld->lsf_proc_dir);
 		fld->lsf_proc_dir = NULL;
 	}
 	EXIT;
 }
 #else
 static int fld_server_proc_init(struct lu_server_fld *fld)
 {
 	return 0;
 }

 static void fld_server_proc_fini(struct lu_server_fld *fld)
 {
 	return;
 }
 #endif

 int fld_server_init(const struct lu_env *env, struct lu_server_fld *fld,
 		    struct dt_device *dt, const char *prefix, int mds_node_id,
 		    int type)
 {
 	int cache_size, cache_threshold;
 	int rc;
 	ENTRY;

 	snprintf(fld->lsf_name, sizeof(fld->lsf_name),
 		 "srv-%s", prefix);

 	cache_size = FLD_SERVER_CACHE_SIZE /
 		sizeof(struct fld_cache_entry);

 	cache_threshold = cache_size *
 		FLD_SERVER_CACHE_THRESHOLD / 100;

 	mutex_init(&fld->lsf_lock);
 	fld->lsf_cache = fld_cache_init(fld->lsf_name,
 					cache_size, cache_threshold);
 	if (IS_ERR(fld->lsf_cache)) {
 		rc = PTR_ERR(fld->lsf_cache);
 		fld->lsf_cache = NULL;
 		GOTO(out, rc);
 	}

 	if (!mds_node_id && type == LU_SEQ_RANGE_MDT) {
 		rc = fld_index_init(env, fld, dt);
 		if (rc)
 			GOTO(out, rc);
 	} else {
 		fld->lsf_obj = NULL;
 	}

 	rc = fld_server_proc_init(fld);
 	if (rc)
 		GOTO(out, rc);

 	fld->lsf_control_exp = NULL;

 	GOTO(out, rc);

 out:
 	if (rc)
 		fld_server_fini(env, fld);
 	return rc;
 }
 EXPORT_SYMBOL(fld_server_init);

 void fld_server_fini(const struct lu_env *env, struct lu_server_fld *fld)
 {
 	ENTRY;

 	fld_server_proc_fini(fld);
 	fld_index_fini(env, fld);

 	if (fld->lsf_cache != NULL) {
 		if (!IS_ERR(fld->lsf_cache))
 			fld_cache_fini(fld->lsf_cache);
 		fld->lsf_cache = NULL;
 	}

 	EXIT;
 }
 EXPORT_SYMBOL(fld_server_fini);

 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
 MODULE_DESCRIPTION("Lustre FLD");
 MODULE_LICENSE("GPL");

 cfs_module(mdd, "0.1.0", fld_mod_init, fld_mod_exit);
	/*
	* GPL HEADER START
	*
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 only,
	* as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License version 2 for more details (a copy is included
	* in the LICENSE file that accompanied this code).
	*
	* You should have received a copy of the GNU General Public License
	* version 2 along with this program; If not, see
	* http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
	*
	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
	* CA 95054 USA or visit www.sun.com if you need additional information or
	* have any questions.
	*
	* GPL HEADER END
	*/
	/*
	* Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
	* Use is subject to license terms.
	*
	* Copyright (c) 2011, 2013, Intel Corporation.
	*/
	/*
	* This file is part of Lustre, http://www.lustre.org/
	* Lustre is a trademark of Sun Microsystems, Inc.
	*
	* lustre/fld/fld_handler.c
	*
	* FLD (Fids Location Database)
	*
	* Author: Yury Umanets <umka@clusterfs.com>
	* Author: WangDi <wangdi@clusterfs.com>
	* Author: Pravin Shelar <pravin.shelar@sun.com>
	*/

	#define DEBUG_SUBSYSTEM S_FLD

	# include <linux/libcfs/libcfs.h>
	# include <linux/module.h>
	# include <linux/jbd.h>
	# include <asm/div64.h>

	#include <obd.h>
	#include <obd_class.h>
	#include <lustre_ver.h>
	#include <obd_support.h>
	#include <lprocfs_status.h>

	#include <md_object.h>
	#include <lustre_fid.h>
	#include <lustre_req_layout.h>
	#include "fld_internal.h"
	#include <lustre_fid.h>


	/* context key constructor/destructor: fld_key_init, fld_key_fini */
	LU_KEY_INIT_FINI(fld, struct fld_thread_info);

	/* context key: fld_thread_key */
	LU_CONTEXT_KEY_DEFINE(fld, LCT_MD_THREAD \| LCT_DT_THREAD \| LCT_MG_THREAD);

	proc_dir_entry_t *fld_type_proc_dir = NULL;

	static int __init fld_mod_init(void)
	{
	fld_type_proc_dir = lprocfs_register(LUSTRE_FLD_NAME,
	proc_lustre_root,
	NULL, NULL);
	if (IS_ERR(fld_type_proc_dir))
	return PTR_ERR(fld_type_proc_dir);

	LU_CONTEXT_KEY_INIT(&fld_thread_key);
	lu_context_key_register(&fld_thread_key);
	return 0;
	}

	static void __exit fld_mod_exit(void)
	{
	lu_context_key_degister(&fld_thread_key);
	if (fld_type_proc_dir != NULL && !IS_ERR(fld_type_proc_dir)) {
	lprocfs_remove(&fld_type_proc_dir);
	fld_type_proc_dir = NULL;
	}
	}

	int fld_declare_server_create(const struct lu_env *env,
	struct lu_server_fld *fld,
	struct lu_seq_range *range,
	struct thandle *th)
	{
	int rc;

	rc = fld_declare_index_create(env, fld, range, th);
	RETURN(rc);
	}
	EXPORT_SYMBOL(fld_declare_server_create);

	/**
	* Insert FLD index entry and update FLD cache.
	*
	* This function is called from the sequence allocator when a super-sequence
	* is granted to a server.
	*/
	int fld_server_create(const struct lu_env env, struct lu_server_fld fld,
	struct lu_seq_range range, struct thandle th)
	{
	int rc;

	mutex_lock(&fld->lsf_lock);
	rc = fld_index_create(env, fld, range, th);
	mutex_unlock(&fld->lsf_lock);

	RETURN(rc);
	}
	EXPORT_SYMBOL(fld_server_create);

	/**
	* Lookup mds by seq, returns a range for given seq.
	*
	* If that entry is not cached in fld cache, request is sent to super
	* sequence controller node (MDT0). All other MDT[1...N] and client
	* cache fld entries, but this cache is not persistent.
	*/
	int fld_server_lookup(const struct lu_env env, struct lu_server_fld fld,
	seqno_t seq, struct lu_seq_range *range)
	{
	struct lu_seq_range *erange;
	struct fld_thread_info *info;
	int rc;
	ENTRY;

	info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
	LASSERT(info != NULL);
	erange = &info->fti_lrange;

	/* Lookup it in the cache. */
	rc = fld_cache_lookup(fld->lsf_cache, seq, erange);
	if (rc == 0) {
	if (unlikely(fld_range_type(erange) != fld_range_type(range) &&
	!fld_range_is_any(range))) {
	CERROR("%s: FLD cache range "DRANGE" does not match"
	"requested flag %x: rc = %d\n", fld->lsf_name,
	PRANGE(erange), range->lsr_flags, -EIO);
	RETURN(-EIO);
	}
	range = erange;
	RETURN(0);
	}

	if (fld->lsf_obj) {
	/* On server side, all entries should be in cache.
	* If we can not find it in cache, just return error */
	CERROR("%s: Cannot find sequence "LPX64": rc = %d\n",
	fld->lsf_name, seq, -EIO);
	RETURN(-EIO);
	} else {
	LASSERT(fld->lsf_control_exp);
	/* send request to mdt0 i.e. super seq. controller.
	* This is temporary solution, long term solution is fld
	* replication on all mdt servers.
	*/
	range->lsr_start = seq;
	rc = fld_client_rpc(fld->lsf_control_exp,
	range, FLD_LOOKUP);
	if (rc == 0)
	fld_cache_insert(fld->lsf_cache, range);
	}
	RETURN(rc);
	}
	EXPORT_SYMBOL(fld_server_lookup);

	/**
	* All MDT server handle fld lookup operation. But only MDT0 has fld index.
	* if entry is not found in cache we need to forward lookup request to MDT0
	*/

	static int fld_server_handle(struct lu_server_fld *fld,
	const struct lu_env *env,
	__u32 opc, struct lu_seq_range *range,
	struct fld_thread_info *info)
	{
	int rc;
	ENTRY;

	switch (opc) {
	case FLD_LOOKUP:
	rc = fld_server_lookup(env, fld, range->lsr_start, range);
	break;
	default:
	rc = -EINVAL;
	break;
	}

	CDEBUG(D_INFO, "%s: FLD req handle: error %d (opc: %d, range: "
	DRANGE"\n", fld->lsf_name, rc, opc, PRANGE(range));

	RETURN(rc);

	}

	static int fld_req_handle(struct ptlrpc_request *req,
	struct fld_thread_info *info)
	{
	struct obd_export *exp = req->rq_export;
	struct lu_site *site = exp->exp_obd->obd_lu_dev->ld_site;
	struct lu_seq_range *in;
	struct lu_seq_range *out;
	int rc;
	__u32 *opc;
	ENTRY;

	rc = req_capsule_server_pack(info->fti_pill);
	if (rc)
	RETURN(err_serious(rc));

	opc = req_capsule_client_get(info->fti_pill, &RMF_FLD_OPC);
	if (opc != NULL) {
	in = req_capsule_client_get(info->fti_pill, &RMF_FLD_MDFLD);
	if (in == NULL)
	RETURN(err_serious(-EPROTO));
	out = req_capsule_server_get(info->fti_pill, &RMF_FLD_MDFLD);
	if (out == NULL)
	RETURN(err_serious(-EPROTO));
	out = in;

	/* For old 2.0 client, the 'lsr_flags' is uninitialized.
	* Set it as 'LU_SEQ_RANGE_MDT' by default. */
	if (!(exp_connect_flags(exp) & OBD_CONNECT_64BITHASH) &&
	!(exp_connect_flags(exp) & OBD_CONNECT_MDS_MDS) &&
	!(exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT) &&
	!exp->exp_libclient)
	fld_range_set_mdt(out);

	rc = fld_server_handle(lu_site2seq(site)->ss_server_fld,
	req->rq_svc_thread->t_env,
	*opc, out, info);
	} else {
	rc = err_serious(-EPROTO);
	}

	RETURN(rc);
	}

	static void fld_thread_info_init(struct ptlrpc_request *req,
	struct fld_thread_info *info)
	{
	info->fti_pill = &req->rq_pill;
	/* Init request capsule. */
	req_capsule_init(info->fti_pill, req, RCL_SERVER);
	req_capsule_set(info->fti_pill, &RQF_FLD_QUERY);
	}

	static void fld_thread_info_fini(struct fld_thread_info *info)
	{
	req_capsule_fini(info->fti_pill);
	}

	static int fld_handle(struct ptlrpc_request *req)
	{
	struct fld_thread_info *info;
	const struct lu_env *env;
	int rc;

	env = req->rq_svc_thread->t_env;
	LASSERT(env != NULL);

	info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
	LASSERT(info != NULL);

	fld_thread_info_init(req, info);
	rc = fld_req_handle(req, info);
	fld_thread_info_fini(info);

	return rc;
	}

	/*
	* Entry point for handling FLD RPCs called from MDT.
	*/
	int fld_query(struct com_thread_info *info)
	{
	return fld_handle(info->cti_pill->rc_req);
	}
	EXPORT_SYMBOL(fld_query);

	/*
	* Returns true, if fid is local to this server node.
	*
	* WARNING: this function is not guaranteed to return false if fid is
	* remote: it makes an educated conservative guess only.
	*
	* fid_is_local() is supposed to be used in assertion checks only.
	*/
	int fid_is_local(const struct lu_env *env,
	struct lu_site site, const struct lu_fid fid)
	{
	int result;
	struct seq_server_site *ss_site;
	struct lu_seq_range *range;
	struct fld_thread_info *info;
	ENTRY;

	info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
	range = &info->fti_lrange;

	result = 1; /* conservatively assume fid is local */
	ss_site = lu_site2seq(site);
	if (ss_site->ss_client_fld != NULL) {
	int rc;

	rc = fld_cache_lookup(ss_site->ss_client_fld->lcf_cache,
	fid_seq(fid), range);
	if (rc == 0)
	result = (range->lsr_index == ss_site->ss_node_id);
	}
	return result;
	}
	EXPORT_SYMBOL(fid_is_local);

	static void fld_server_proc_fini(struct lu_server_fld *fld);

	#ifdef LPROCFS
	static int fld_server_proc_init(struct lu_server_fld *fld)
	{
	int rc = 0;
	ENTRY;

	fld->lsf_proc_dir = lprocfs_register(fld->lsf_name,
	fld_type_proc_dir,
	fld_server_proc_list, fld);
	if (IS_ERR(fld->lsf_proc_dir)) {
	rc = PTR_ERR(fld->lsf_proc_dir);
	RETURN(rc);
	}

	rc = lprocfs_seq_create(fld->lsf_proc_dir, "fldb", 0444,
	&fld_proc_seq_fops, fld);
	if (rc) {
	lprocfs_remove(&fld->lsf_proc_dir);
	fld->lsf_proc_dir = NULL;
	}

	RETURN(rc);
	}

	static void fld_server_proc_fini(struct lu_server_fld *fld)
	{
	ENTRY;
	if (fld->lsf_proc_dir != NULL) {
	if (!IS_ERR(fld->lsf_proc_dir))
	lprocfs_remove(&fld->lsf_proc_dir);
	fld->lsf_proc_dir = NULL;
	}
	EXIT;
	}
	#else
	static int fld_server_proc_init(struct lu_server_fld *fld)
	{
	return 0;
	}

	static void fld_server_proc_fini(struct lu_server_fld *fld)
	{
	return;
	}
	#endif

	int fld_server_init(const struct lu_env env, struct lu_server_fld fld,
	struct dt_device dt, const char prefix, int mds_node_id,
	int type)
	{
	int cache_size, cache_threshold;
	int rc;
	ENTRY;

	snprintf(fld->lsf_name, sizeof(fld->lsf_name),
	"srv-%s", prefix);

	cache_size = FLD_SERVER_CACHE_SIZE /
	sizeof(struct fld_cache_entry);

	cache_threshold = cache_size *
	FLD_SERVER_CACHE_THRESHOLD / 100;

	mutex_init(&fld->lsf_lock);
	fld->lsf_cache = fld_cache_init(fld->lsf_name,
	cache_size, cache_threshold);
	if (IS_ERR(fld->lsf_cache)) {
	rc = PTR_ERR(fld->lsf_cache);
	fld->lsf_cache = NULL;
	GOTO(out, rc);
	}

	if (!mds_node_id && type == LU_SEQ_RANGE_MDT) {
	rc = fld_index_init(env, fld, dt);
	if (rc)
	GOTO(out, rc);
	} else {
	fld->lsf_obj = NULL;
	}

	rc = fld_server_proc_init(fld);
	if (rc)
	GOTO(out, rc);

	fld->lsf_control_exp = NULL;

	GOTO(out, rc);

	out:
	if (rc)
	fld_server_fini(env, fld);
	return rc;
	}
	EXPORT_SYMBOL(fld_server_init);

	void fld_server_fini(const struct lu_env env, struct lu_server_fld fld)
	{
	ENTRY;

	fld_server_proc_fini(fld);
	fld_index_fini(env, fld);

	if (fld->lsf_cache != NULL) {
	if (!IS_ERR(fld->lsf_cache))
	fld_cache_fini(fld->lsf_cache);
	fld->lsf_cache = NULL;
	}

	EXIT;
	}
	EXPORT_SYMBOL(fld_server_fini);

	MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
	MODULE_DESCRIPTION("Lustre FLD");
	MODULE_LICENSE("GPL");

	cfs_module(mdd, "0.1.0", fld_mod_init, fld_mod_exit);