// SPDX-License-Identifier: GPL-2.0

/*
 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2011, 2017, Intel Corporation.
 */

/*
 * This file is part of Lustre, http://www.lustre.org/
 *
 * Author: Phil Schwan <phil@clusterfs.com>
 * Author: Peter Braam <braam@clusterfs.com>
 * Author: Mike Shaver <shaver@clusterfs.com>
 * Author: Nathan Rutman <nathan@clusterfs.com>
 */

#define DEBUG_SUBSYSTEM S_LOV

#include <cl_object.h>
#include <lustre_dlm.h>
#include <lustre_fid.h>
#include <uapi/linux/lustre/lustre_ioctl.h>
#include <lustre_ioctl_old.h>
#include <lustre_lib.h>
#include <lustre_mds.h>
#include <lustre_net.h>
#include <uapi/linux/lustre/lustre_param.h>
#include <lustre_swab.h>
#include <lprocfs_status.h>
#include <obd_class.h>
#include <obd_support.h>

#include "lov_internal.h"

/* Keep a refcount of lov->tgt usage to prevent racing with addition/deletion.
 * Any function that expects lov_tgts to remain stationary must take a ref.
 */
void lov_tgts_getref(struct obd_device *obd)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;

	/* nobody gets through here until lov_putref is done */
	mutex_lock(&ltd->ltd_mutex);
	atomic_inc(&ltd->ltd_refcount);
	mutex_unlock(&ltd->ltd_mutex);
}

static void __lov_del_obd(struct obd_device *obd, struct lov_tgt_desc *tgt);

void lov_tgts_putref(struct obd_device *obd)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_obd *lov = &obd->u.lov;

	mutex_lock(&ltd->ltd_mutex);
	/* ok to dec to 0 more than once -- ltd_exp's will be null */
	if (atomic_dec_and_test(&ltd->ltd_refcount) && ltd->ltd_death_row) {
		struct lov_tgt_desc *tgt, *n;
		LIST_HEAD(kill);

		CDEBUG(D_CONFIG, "destroying %d lov targets\n",
		       ltd->ltd_death_row);
		lov_foreach_tgt(lov, tgt) {
			if (!tgt->ltd_reap)
				continue;

			list_add(&tgt->ltd_kill, &kill);
			lu_tgt_pool_remove(&ltd->ltd_tgt_pool,
					   tgt->ltd_index);
			ltd_del_tgt(ltd, tgt);
			ltd->ltd_death_row--;
		}
		mutex_unlock(&ltd->ltd_mutex);

		list_for_each_entry_safe(tgt, n, &kill, ltd_kill) {
			list_del(&tgt->ltd_kill);
			/* Disconnect */
			__lov_del_obd(obd, tgt);
		}
	} else {
		mutex_unlock(&ltd->ltd_mutex);
	}
}

static int lov_notify(struct obd_device *obd, struct obd_device *watched,
		      enum obd_notify_event ev);

static int lov_connect_osc(struct obd_device *obd, u32 index, int activate,
			   struct obd_connect_data *data)
{
	struct lov_obd *lov = &obd->u.lov;
	struct obd_uuid *tgt_uuid;
	struct obd_device *tgt_obd;
	static struct obd_uuid lov_osc_uuid = { "LOV_OSC_UUID" };
	struct obd_import *imp;
	struct lov_tgt_desc *tgt;
	int rc;

	ENTRY;
	tgt = lov_tgt(lov, index);
	if (!tgt)
		RETURN(-EINVAL);

	tgt_uuid = &tgt->ltd_uuid;
	tgt_obd = tgt->ltd_obd;

	if (!test_bit(OBDF_SET_UP, tgt_obd->obd_flags)) {
		rc = -EINVAL;
		CERROR("%s: target not set up: rc = %d\n",
		       obd_uuid2str(tgt_uuid), rc);
		RETURN(rc);
	}

	/* override the sp_me from lov */
	tgt_obd->u.cli.cl_sp_me = lov->lov_sp_me;

	if (data && (data->ocd_connect_flags & OBD_CONNECT_INDEX))
		data->ocd_index = index;

	/*
	 * Divine LOV knows that OBDs under it are OSCs.
	 */
	imp = tgt_obd->u.cli.cl_import;

	if (activate) {
		tgt_obd->obd_no_recov = 0;
		/* FIXME this is probably supposed to be
		   ptlrpc_set_import_active.  Horrible naming. */
		ptlrpc_activate_import(imp, false);
	}

	rc = obd_register_observer(tgt_obd, obd);
	if (rc) {
		CERROR("%s: target register_observer error: rc = %d\n",
		       obd_uuid2str(tgt_uuid), rc);
		RETURN(rc);
	}

	if (imp->imp_invalid) {
		CDEBUG(D_CONFIG, "%s: not connecting - administratively disabled\n",
		       obd_uuid2str(tgt_uuid));
		RETURN(0);
	}

	rc = obd_connect(NULL, &tgt->ltd_exp, tgt_obd, &lov_osc_uuid, data,
			lov->lov_cache);
	if (rc || !tgt->ltd_exp) {
		CERROR("%s: target connect error: rc = %d\n",
		       obd_uuid2str(tgt_uuid), rc);
		obd_register_observer(tgt_obd, NULL);
		RETURN(-ENODEV);
	}

	tgt->ltd_reap = 0;

	CDEBUG(D_CONFIG, "Connected tgt idx %d %s (%s) %sactive\n", index,
	       obd_uuid2str(tgt_uuid), tgt_obd->obd_name, activate ? "":"in");

	if (lov->lov_tgts_kobj) {
		/* Even if we failed, that's ok */
		rc = sysfs_create_link(lov->lov_tgts_kobj,
				       &tgt_obd->obd_kset.kobj,
				       tgt_obd->obd_name);
		if (rc) {
			CERROR("%s: can't register LOV target /sys/fs/lustre/%s/%s/target_obds/%s : rc = %d\n",
			       obd->obd_name, obd->obd_type->typ_name,
			       obd->obd_name, tgt->ltd_exp->exp_obd->obd_name,
			       rc);
		}
	}
	RETURN(0);
}

static int lov_connect(const struct lu_env *env, struct obd_export **exp,
		       struct obd_device *obd, struct obd_uuid *cluuid,
		       struct obd_connect_data *data, void *localdata)
{
	struct lov_obd *lov = &obd->u.lov;
	struct lov_tgt_desc *tgt;
	struct lustre_handle conn;
	int rc;

	ENTRY;
	CDEBUG(D_CONFIG, "connect #%d\n", lov->lov_connects);

	rc = class_connect(&conn, obd, cluuid);
	if (rc)
		RETURN(rc);

	*exp = class_conn2export(&conn);

	/* Why should there ever be more than 1 connect? */
	lov->lov_connects++;
	LASSERT(lov->lov_connects == 1);

	memset(&lov->lov_ocd, 0, sizeof(lov->lov_ocd));
	if (data)
		lov->lov_ocd = *data;

	lov_tgts_getref(obd);

	if (localdata) {
		lov->lov_cache = localdata;
		cl_cache_incref(lov->lov_cache);
	}

	lov_foreach_tgt(lov, tgt) {
		if (obd_uuid_empty(&tgt->ltd_uuid))
			continue;

		/* Flags will be lowest common denominator */
		rc = lov_connect_osc(obd, tgt->ltd_index, tgt->ltd_activate,
				     &lov->lov_ocd);
		if (rc) {
			CERROR("%s: lov connect tgt %d failed: rc = %d\n",
			       obd->obd_name, tgt->ltd_index, rc);
			continue;
		}
		/* connect to administrative disabled ost */
		if (!tgt->ltd_exp)
			continue;

		rc = lov_notify(obd, tgt->ltd_exp->exp_obd,
				OBD_NOTIFY_CONNECT);
		if (rc) {
			CERROR("%s: error sending notify: rc = %d\n",
			       obd->obd_name, rc);
		}
	}

	lov_tgts_putref(obd);

	RETURN(0);
}

static int lov_disconnect_obd(struct obd_device *obd, struct lov_tgt_desc *tgt)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_obd *lov = &obd->u.lov;
	struct obd_device *osc_obd;
	int rc;

	ENTRY;
	osc_obd = class_exp2obd(tgt->ltd_exp);
	CDEBUG(D_CONFIG, "%s: disconnecting target %s\n", obd->obd_name,
	       osc_obd ? osc_obd->obd_name : "<no obd>");

	if (tgt->ltd_active) {
		tgt->ltd_active = 0;
		ltd->ltd_lov_desc.ld_active_tgt_count--;
		tgt->ltd_exp->exp_obd->obd_inactive = 1;
	}

	if (osc_obd) {
		if (lov->lov_tgts_kobj)
			sysfs_remove_link(lov->lov_tgts_kobj,
					  osc_obd->obd_name);

		/* Pass it on to our clients.
		 * XXX This should be an argument to disconnect,
		 * XXX not a back-door flag on the OBD.  Ah well.
		 */
		osc_obd->obd_force = obd->obd_force;
		osc_obd->obd_fail = obd->obd_fail;
		osc_obd->obd_no_recov = obd->obd_no_recov;
	}

	obd_register_observer(osc_obd, NULL);

	rc = obd_disconnect(tgt->ltd_exp);
	if (rc) {
		CERROR("%s: Target %s disconnect error %d\n",
		       obd->obd_name, tgt->ltd_uuid.uuid, rc);
		rc = 0;
	}

	tgt->ltd_exp = NULL;
	RETURN(0);
}

static int lov_disconnect(struct obd_export *exp)
{
	struct obd_device *obd = class_exp2obd(exp);
	struct lov_obd *lov = &obd->u.lov;
	struct lu_tgt_desc *tgt;
	int rc;

	ENTRY;
	if (!lov->lov_ost_descs.ltd_tgts_size)
		goto out;

	/* Only disconnect the underlying layers on the final disconnect. */
	if (lov->lov_connects == 0) {
		CWARN("%s: was disconnected already #%d\n",
		      obd->obd_name, lov->lov_connects);
		RETURN(0);
	}

	lov->lov_connects--;
	if (lov->lov_connects > 0) {
		/* why should there be more than 1 connect? */
		CWARN("%s: unexpected disconnect #%d\n",
		      obd->obd_name, lov->lov_connects);
		goto out;
	}

	/* hold another ref so lov_del_obd() doesn't spin in putref each time */
	lov_tgts_getref(obd);
	lov_foreach_tgt(lov, tgt) {
		if (tgt->ltd_exp) {
			/* Disconnection is the last we know about an OBD */
			lov_del_target(obd, tgt->ltd_index, NULL, tgt->ltd_gen);
		}
	}
	lov_tgts_putref(obd);

out:
	rc = class_disconnect(exp); /* bz 9811 */
	RETURN(rc);
}

/* Error codes:
 *
 *  -EINVAL  : UUID can't be found in the LOV's target list
 *  -ENOTCONN: The UUID is found, but the target connection is bad (!)
 *  -EBADF   : The UUID is found, but the OBD is the wrong type (!)
 *  any >= 0 : is log target index
 */
static int lov_set_osc_active(struct obd_device *obd, struct obd_uuid *uuid,
			      enum obd_notify_event ev)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_obd *lov = &obd->u.lov;
	struct lov_tgt_desc *tgt;
	bool activate, active;
	int index = -EINVAL;

	ENTRY;
	CDEBUG(D_INFO, "Searching in lov %p for uuid %s event(%d)\n",
	       lov, uuid->uuid, ev);

	lov_tgts_getref(obd);
	lov_foreach_tgt(lov, tgt) {
		if (obd_uuid_equals(uuid, &tgt->ltd_uuid)) {
			index = tgt->ltd_index;
			break;
		}
	}
	if (index < 0)
		GOTO(out, index);

	if (ev == OBD_NOTIFY_DEACTIVATE || ev == OBD_NOTIFY_ACTIVATE) {
		activate = (ev == OBD_NOTIFY_ACTIVATE);

		/*
		 * LU-642, initially inactive OSC could miss the obd_connect,
		 * we make up for it here.
		 */
		if (activate && !tgt->ltd_exp) {
			struct obd_uuid lov_osc_uuid = {"LOV_OSC_UUID"};
			int rc;

			rc = obd_connect(NULL, &tgt->ltd_exp, tgt->ltd_obd,
					 &lov_osc_uuid, &lov->lov_ocd,
					 lov->lov_cache);
			if (rc || !tgt->ltd_exp)
				GOTO(out, index = rc);
		}

		if (tgt->ltd_activate == activate) {
			CDEBUG(D_INFO, "OSC %s already %sactivate!\n",
			       uuid->uuid, activate ? "" : "de");
		} else {
			tgt->ltd_activate = activate;
			CDEBUG(D_CONFIG, "%sactivate OSC %s\n",
			       activate ? "" : "de", obd_uuid2str(uuid));
		}
	} else if (ev == OBD_NOTIFY_INACTIVE || ev == OBD_NOTIFY_ACTIVE) {
		active = (ev == OBD_NOTIFY_ACTIVE);

		if (tgt->ltd_active == active) {
			CDEBUG(D_INFO, "OSC %s already %sactive!\n",
			       uuid->uuid, active ? "" : "in");
			GOTO(out, index);
		}
		CDEBUG(D_CONFIG, "Marking OSC %s %sactive\n",
		       obd_uuid2str(uuid), active ? "" : "in");

		tgt->ltd_active = active;
		if (active) {
			ltd->ltd_lov_desc.ld_active_tgt_count++;
			tgt->ltd_exp->exp_obd->obd_inactive = 0;
		} else {
			ltd->ltd_lov_desc.ld_active_tgt_count--;
			tgt->ltd_exp->exp_obd->obd_inactive = 1;
		}
	} else {
		CERROR("%s: unknown event %d for uuid %s\n", obd->obd_name,
		       ev, uuid->uuid);
	}

	if (tgt->ltd_exp)
		CDEBUG(D_INFO, "%s: lov idx %d conn %llx\n", obd_uuid2str(uuid),
		       tgt->ltd_index, tgt->ltd_exp->exp_handle.h_cookie);

out:
	lov_tgts_putref(obd);
	RETURN(index);
}

static int lov_notify(struct obd_device *obd, struct obd_device *watched,
		      enum obd_notify_event ev)
{
	int rc = 0;
	struct lov_obd *lov = &obd->u.lov;
	ENTRY;

	down_read(&lov->lov_notify_lock);
	if (!lov->lov_connects)
		GOTO(out_notify_lock, rc = 0);

	if (ev == OBD_NOTIFY_ACTIVE || ev == OBD_NOTIFY_INACTIVE ||
	    ev == OBD_NOTIFY_ACTIVATE || ev == OBD_NOTIFY_DEACTIVATE) {
		struct obd_uuid *uuid;

		LASSERT(watched);

		if (strcmp(watched->obd_type->typ_name, LUSTRE_OSC_NAME)) {
			CERROR("unexpected notification of %s %s\n",
			       watched->obd_type->typ_name, watched->obd_name);
			GOTO(out_notify_lock, rc = -EINVAL);
		}

		uuid = &watched->u.cli.cl_target_uuid;

		/* Set OSC as active before notifying the observer, so the
		 * observer can use the OSC normally.
		 */
		rc = lov_set_osc_active(obd, uuid, ev);
		if (rc < 0) {
			CERROR("%s: event %d failed: rc = %d\n", obd->obd_name,
			       ev, rc);
			GOTO(out_notify_lock, rc);
		}
	}

	/* Pass the notification up the chain. */
	rc = obd_notify_observer(obd, watched, ev);

out_notify_lock:
	up_read(&lov->lov_notify_lock);

	RETURN(rc);
}

static int lov_add_target(struct obd_device *obd, struct obd_uuid *uuidp,
			  u32 index, int gen, int active)
{
	struct lov_obd *lov = &obd->u.lov;
	struct lu_tgt_descs *ltd = &lov->lov_ost_descs;
	struct lov_tgt_desc *tgt;
	struct obd_device *tgt_obd;
	int rc;

	ENTRY;
	CDEBUG(D_CONFIG, "uuid:%s idx:%u gen:%d active:%d\n",
	       uuidp->uuid, index, gen, active);

	if (gen <= 0) {
		CERROR("%s: request to add '%s' with invalid generation: %d\n",
		       obd->obd_name, uuidp->uuid, gen);
		RETURN(-EINVAL);
	}

	tgt_obd = class_find_client_obd(uuidp, LUSTRE_OSC_NAME, &obd->obd_uuid);
	if (tgt_obd == NULL)
		RETURN(-EINVAL);

	mutex_lock(&ltd->ltd_mutex);
	/* check that the index is allocated in the bitmap */
	if (index < ltd->ltd_tgts_size &&
	    test_bit(index, ltd->ltd_tgt_bitmap) && lov_tgt(lov, index)) {
		rc = -EEXIST;
		CERROR("%s: UUID %s already assigned at index %d: rc = %d\n",
		       obd->obd_name, obd_uuid2str(uuidp), index, rc);
		mutex_unlock(&ltd->ltd_mutex);
		RETURN(rc);
	}

	OBD_ALLOC_PTR(tgt);
	if (!tgt) {
		mutex_unlock(&ltd->ltd_mutex);
		RETURN(-ENOMEM);
	}

	CDEBUG(D_CONFIG, "%s: Adding target %s\n", obd->obd_name, uuidp->uuid);
	tgt->ltd_uuid = *uuidp;
	tgt->ltd_obd = tgt_obd;
	/* XXX - add a sanity check on the generation number. */
	tgt->ltd_gen = gen;
	tgt->ltd_index = index;
	tgt->ltd_activate = active;
	rc = ltd_add_tgt(ltd, tgt);
	if (rc < 0) {
		mutex_unlock(&ltd->ltd_mutex);
		OBD_FREE_PTR(tgt);
		RETURN(rc);
	}

	rc = lu_tgt_pool_add(&ltd->ltd_tgt_pool, index, ltd->ltd_tgts_size);
	mutex_unlock(&ltd->ltd_mutex);
	if (rc < 0) {
		OBD_FREE_PTR(tgt);
		RETURN(rc);
	}

	CDEBUG(D_CONFIG, "idx=%d ltd_gen=%d ld_tgt_count=%d\n",
	       index, tgt->ltd_gen, ltd->ltd_lov_desc.ld_tgt_count);

	if (lov->lov_connects == 0) {
		/* lov_connect hasn't been called yet. We'll do the
		 * lov_connect_osc on this target when that fn first runs,
		 * because we don't know the connect flags yet.
		 */
		RETURN(0);
	}

	lov_tgts_getref(obd);

	rc = lov_connect_osc(obd, index, active, &lov->lov_ocd);
	if (rc)
		GOTO(out, rc);

	/* connect to administrative disabled ost */
	if (!tgt->ltd_exp)
		GOTO(out, rc = 0);

	rc = lov_notify(obd, tgt->ltd_exp->exp_obd,
			active ? OBD_NOTIFY_CONNECT : OBD_NOTIFY_INACTIVE);

out:
	if (rc) {
		CERROR("%s: add failed, deleting %s: rc = %d\n",
		       obd->obd_name, obd_uuid2str(&tgt->ltd_uuid), rc);
		lov_del_target(obd, index, NULL, 0);
	}
	lov_tgts_putref(obd);
	RETURN(rc);
}

/* Schedule a target for deletion */
int lov_del_target(struct obd_device *obd, u32 index, struct obd_uuid *uuidp,
		   int gen)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_obd *lov = &obd->u.lov;
	struct lov_tgt_desc *tgt;
	int rc = 0;

	ENTRY;
	if (index >= ltd->ltd_tgts_size || !test_bit(index, ltd->ltd_tgt_bitmap)) {
		CERROR("%s: LOV target index %d >= number of LOV OBDs %d: rc = %d\n",
		       obd->obd_name, index, ltd->ltd_tgts_size, -EINVAL);
		RETURN(-EINVAL);
	}

	/* to make sure there's no ongoing lov_notify() now */
	down_write(&lov->lov_notify_lock);
	lov_tgts_getref(obd);
	tgt = lov_tgt(lov, index);
	if (!tgt) {
		CERROR("%s: LOV target at index %d is not setup: rc = %d\n",
		       obd->obd_name, index, -EINVAL);
		GOTO(out, rc = -EINVAL);
	}

	if (uuidp && !obd_uuid_equals(uuidp, &tgt->ltd_uuid)) {
		CERROR("%s: LOV target UUID %s at index %d doesn't match %s: rc = %d\n",
		       obd->obd_name, lov_uuid2str(lov, index), index,
		       obd_uuid2str(uuidp), -EINVAL);

		GOTO(out, rc = -EINVAL);
	}

	CDEBUG(D_CONFIG, "uuid: %s idx: %d gen: %d exp: %p active: %d\n",
	       lov_uuid2str(lov, index), index, tgt->ltd_gen, tgt->ltd_exp,
	       tgt->ltd_active);

	tgt->ltd_reap = 1;
	ltd->ltd_death_row++;
	/* we really delete it from lov_tgts_putref() */
out:
	lov_tgts_putref(obd);
	up_write(&lov->lov_notify_lock);

	RETURN(rc);
}

static void __lov_del_obd(struct obd_device *obd, struct lov_tgt_desc *tgt)
{
	struct obd_device *osc_obd;

	LASSERT(tgt);
	LASSERT(tgt->ltd_reap);

	osc_obd = class_exp2obd(tgt->ltd_exp);

	CDEBUG(D_CONFIG, "Removing tgt %s : %s\n", tgt->ltd_uuid.uuid,
	       osc_obd ? osc_obd->obd_name : "<no obd>");

	if (tgt->ltd_exp)
		lov_disconnect_obd(obd, tgt);

	OBD_FREE_PTR(tgt);

	/* Manual cleanup - no cleanup logs to clean up the osc's.  We must
	 * do it ourselves. And we can't do it from lov_cleanup,
	 * because we just lost our only reference to it.
	 */
	if (osc_obd)
		class_manual_cleanup(osc_obd);
}

void lov_fix_desc_stripe_size(__u64 *val)
{
	if (*val < LOV_MIN_STRIPE_SIZE) {
		if (*val != 0)
			LCONSOLE_INFO("Increasing default stripe size to "
				      "minimum %u\n",
				      LOV_DESC_STRIPE_SIZE_DEFAULT);
		*val = LOV_DESC_STRIPE_SIZE_DEFAULT;
	} else if (*val & (LOV_MIN_STRIPE_SIZE - 1)) {
		*val &= ~(LOV_MIN_STRIPE_SIZE - 1);
		LCONSOLE_WARN("Changing default stripe size to %llu (a "
			      "multiple of %u)\n",
			      *val, LOV_MIN_STRIPE_SIZE);
	}
}

void lov_fix_desc_stripe_count(__u32 *val)
{
	if (*val == 0)
		*val = 1;
}

void lov_fix_desc_pattern(__u32 *val)
{
	/* from lov_setstripe */
	if ((*val != 0) && !lov_pattern_supported_normal_comp(*val)) {
		LCONSOLE_WARN("lov: Unknown stripe pattern: %#x\n", *val);
		*val = 0;
	}
}

void lov_fix_desc_qos_maxage(__u32 *val)
{
	if (*val == 0)
		*val = LOV_DESC_QOS_MAXAGE_DEFAULT;
}

void lov_fix_desc(struct lov_desc *desc)
{
	lov_fix_desc_stripe_size(&desc->ld_default_stripe_size);
	lov_fix_desc_stripe_count(&desc->ld_default_stripe_count);
	lov_fix_desc_pattern(&desc->ld_pattern);
	lov_fix_desc_qos_maxage(&desc->ld_qos_maxage);
}

int lov_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_desc *desc;
	struct lov_obd *lov = &obd->u.lov;
	int rc;
	ENTRY;

	if (LUSTRE_CFG_BUFLEN(lcfg, 1) < 1) {
		CERROR("%s: LOV setup requires a descriptor: rc = %d\n",
		       obd->obd_name, -EINVAL);
		RETURN(-EINVAL);
	}

	desc = (struct lov_desc *)lustre_cfg_buf(lcfg, 1);

	if (sizeof(*desc) > LUSTRE_CFG_BUFLEN(lcfg, 1)) {
		CERROR("%s: descriptor size wrong: %d > %d: rc = %d\n",
		       obd->obd_name, (int)sizeof(*desc),
		       LUSTRE_CFG_BUFLEN(lcfg, 1), -EINVAL);
		RETURN(-EINVAL);
	}

	if (desc->ld_magic != LOV_DESC_MAGIC) {
		if (desc->ld_magic == __swab32(LOV_DESC_MAGIC)) {
			CDEBUG(D_OTHER, "%s: Swabbing lov desc %p\n",
			       obd->obd_name, desc);
			lustre_swab_lov_desc(desc);
		} else {
			CERROR("%s: Bad lov desc magic: %#x: rc = %d\n",
			       obd->obd_name, desc->ld_magic, -EINVAL);
			RETURN(-EINVAL);
		}
	}

	rc = lu_tgt_descs_init(ltd, false);
	if (rc < 0)
		RETURN(rc);

	lov_fix_desc(desc);
	desc->ld_tgt_count = 0;
	desc->ld_active_tgt_count = 0;
	ltd->ltd_lov_desc = *desc;

	lov->lov_sp_me = LUSTRE_SP_CLI;
	init_rwsem(&lov->lov_notify_lock);

	INIT_LIST_HEAD(&lov->lov_pool_list);
	lov->lov_pool_count = 0;
	rc = lov_pool_hash_init(&lov->lov_pools_hash_body);
	if (rc < 0) {
		lu_tgt_descs_fini(ltd);
		GOTO(out, rc);
	}

	rc = lu_tgt_pool_init(&ltd->ltd_tgt_pool, 0);
	if (rc < 0) {
		lov_pool_hash_destroy(&lov->lov_pools_hash_body);
		lu_tgt_descs_fini(ltd);
		GOTO(out, rc);
	}

	rc = lov_tunables_init(obd);
	if (rc < 0) {
		lu_tgt_pool_free(&ltd->ltd_tgt_pool);
		lov_pool_hash_destroy(&lov->lov_pools_hash_body);
		lu_tgt_descs_fini(ltd);
		GOTO(out, rc);
	}

	lov->lov_tgts_kobj = kobject_create_and_add("target_obds",
						    &obd->obd_kset.kobj);
out:
	return rc;
}

int lov_cleanup(struct obd_device *obd)
{
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_obd *lov = &obd->u.lov;
	struct lov_pool_desc *pool, *tmp;
	struct lu_tgt_desc *tgt;

	ENTRY;
	if (lov->lov_tgts_kobj) {
		kobject_put(lov->lov_tgts_kobj);
		lov->lov_tgts_kobj = NULL;
	}

	list_for_each_entry_safe(pool, tmp, &lov->lov_pool_list, pool_list) {
		/* free pool structs */
		CDEBUG(D_INFO, "delete pool %p\n", pool);
		/* In the function below, .hs_keycmp resolves to
		 * pool_hashkey_keycmp() */
		lov_pool_del(obd, pool->pool_name);
	}
	lov_pool_hash_destroy(&lov->lov_pools_hash_body);
	lu_tgt_pool_free(&ltd->ltd_tgt_pool);

	lprocfs_obd_cleanup(obd);

	lov_tgts_getref(obd);
	lov_foreach_tgt(lov, tgt) {
		/* Inactive targets may never have connected */
		if (tgt->ltd_active)
			/* We should never get here - these
			 * should have been removed in the
			 * disconnect.
			 */
			CERROR("%s: lov tgt %d not cleaned! deathrow=%d, lovrc=%d\n",
			       obd->obd_name, tgt->ltd_index,
			       ltd->ltd_death_row,
			       atomic_read(&ltd->ltd_refcount));
		lov_del_target(obd, tgt->ltd_index, NULL, 0);
	}
	lov_tgts_putref(obd);

	lu_tgt_descs_fini(ltd);

	if (lov->lov_cache != NULL) {
		cl_cache_decref(lov->lov_cache);
		lov->lov_cache = NULL;
	}

	RETURN(0);
}

int lov_process_config_base(struct obd_device *obd, struct lustre_cfg *lcfg,
			    u32 *indexp, int *genp)
{
	struct obd_uuid obd_uuid;
	int cmd;
	int rc = 0;

	ENTRY;
	switch (cmd = lcfg->lcfg_command) {
	case LCFG_ADD_MDC:
	case LCFG_DEL_MDC:
		break;
	case LCFG_LOV_ADD_OBD:
	case LCFG_LOV_ADD_INA:
	case LCFG_LOV_DEL_OBD: {
		u32 index;
		int gen;

		/* lov_modify_tgts add  0:lov_mdsA  1:ost1_UUID  2:0  3:1 */
		if (LUSTRE_CFG_BUFLEN(lcfg, 1) > sizeof(obd_uuid.uuid))
			GOTO(out, rc = -EINVAL);

		obd_str2uuid(&obd_uuid,  lustre_cfg_buf(lcfg, 1));

		rc = kstrtou32(lustre_cfg_buf(lcfg, 2), 10, indexp);
		if (rc)
			GOTO(out, rc);
		rc = kstrtoint(lustre_cfg_buf(lcfg, 3), 10, genp);
		if (rc)
			GOTO(out, rc);
		index = *indexp;
		gen = *genp;
		if (cmd == LCFG_LOV_ADD_OBD)
			rc = lov_add_target(obd, &obd_uuid, index, gen, 1);
		else if (cmd == LCFG_LOV_ADD_INA)
			rc = lov_add_target(obd, &obd_uuid, index, gen, 0);
		else
			rc = lov_del_target(obd, index, &obd_uuid, gen);

		GOTO(out, rc);
	}
	case LCFG_PARAM: {
		ssize_t count;

		count = class_modify_config(lcfg, PARAM_LOV,
					    &obd->obd_kset.kobj);
		GOTO(out, rc = count < 0 ? count : 0);
	}
	case LCFG_POOL_NEW:
	case LCFG_POOL_ADD:
	case LCFG_POOL_DEL:
	case LCFG_POOL_REM:
		GOTO(out, rc);

	default: {
		CERROR("%s: Unknown command: %d: rc = %d\n",
		       obd->obd_name, lcfg->lcfg_command, -EINVAL);
		GOTO(out, rc = -EINVAL);
	}
	} /* end switch */
out:
	RETURN(rc);
}

static int lov_statfs(const struct lu_env *env, struct obd_export *exp,
		      struct obd_statfs *osfs, time64_t max_age, __u32 flags)
{
	struct obd_device *obd = class_exp2obd(exp);
	struct lov_obd *lov = &obd->u.lov;
	struct obd_info oinfo = {
		.oi_osfs = osfs,
		.oi_flags = flags,
	};
	struct ptlrpc_request_set *rqset;
	struct lov_request_set *set = NULL;
	struct lov_request *req;
	int rc = 0;
	int rc2;

	ENTRY;
	rqset = ptlrpc_prep_set();
	if (rqset == NULL)
		RETURN(-ENOMEM);

	rc = lov_prep_statfs_set(obd, &oinfo, &set);
	if (rc < 0)
		GOTO(out_rqset, rc);

	list_for_each_entry(req, &set->set_list, rq_link) {
		struct lu_tgt_desc *tgt = lov_tgt(lov, req->rq_idx);

		rc = obd_statfs_async(tgt->ltd_exp, &req->rq_oi, max_age,
				      rqset);
		if (rc < 0)
			GOTO(out_set, rc);
	}

	rc = ptlrpc_set_wait(env, rqset);

out_set:
	if (rc < 0)
		atomic_set(&set->set_completes, 0);

	rc2 = lov_fini_statfs_set(set);
	if (rc == 0)
		rc = rc2;

out_rqset:
	ptlrpc_set_destroy(rqset);

	RETURN(rc);
}

/**
 * lov_fid2path() - retrieve corresponding MDT FID from given OST FID
 * @karg: pointer to struct getinfo_fid2path{}, carrying the OST FID
 *        as the input, and the MDT FID as the output
 *
 * Note: the OST index is retrieved from upper layer's u.gf_root_fid
 */
static int lov_fid2path(struct lov_obd *lov, int len, void *karg,
			void __user *uarg)
{
	struct lov_tgt_desc *tgt = NULL;
	struct getinfo_fid2path *gf;
	u32 ost_idx;
	int rc;

	gf = karg;
	ost_idx = gf->gf_u.gf_root_fid->f_oid;
	if (!fid_is_sane(&gf->gf_fid))
		RETURN(-EINVAL);

	tgt = lov_tgt(lov, ost_idx);
	if (!tgt) {
		CDEBUG(D_IOCTL, DFID" retrieve tgt failed, idx:%u\n",
		       PFID(&gf->gf_fid), ost_idx);
		RETURN(-EIO);
	}

	rc = obd_iocontrol(OBD_IOC_FID2PATH, tgt->ltd_exp, len, gf, uarg);
	if (rc)
		CDEBUG(D_IOCTL, "%s: err consult "DFID" on OST: rc=%d\n",
		       tgt->ltd_exp->exp_obd->obd_name,
		       PFID(&gf->gf_fid), rc);

	RETURN(rc);
}

static int lov_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
			 void *karg, void __user *uarg)
{
	struct obd_device *obd = class_exp2obd(exp);
	struct lov_obd *lov = &obd->u.lov;
	struct lu_tgt_descs *ltd = &lov->lov_ost_descs;
	int rc = 0, count = ltd->ltd_tgts_size;
	struct lov_tgt_desc *tgt = NULL;

	ENTRY;
	CDEBUG(D_IOCTL, "%s: cmd=%x len=%u karg=%pK uarg=%pK\n",
	       exp->exp_obd->obd_name, cmd, len, karg, uarg);

	/* exit early for unknown ioctl types. */
	if (unlikely(_IOC_TYPE(cmd) != 'f' && !IOC_OSC_SET_ACTIVE_ALLOW(cmd)))
		RETURN(OBD_IOC_DEBUG(D_IOCTL, obd->obd_name, cmd, "unknown",
				     -ENOTTY));

	/* can't do a generic karg == NULL check here, since it is too noisy and
	 * we need to return -ENOTTY for unsupported ioctls instead of -EINVAL.
	 */
	switch (cmd) {
	case IOC_OBD_STATFS: {
		struct obd_ioctl_data *data;
		struct obd_device *osc_obd;
		struct obd_statfs stat_buf = {0};
		struct obd_import *imp;
		__u32 index;
		__u32 flags;

		if (unlikely(karg == NULL))
			RETURN(OBD_IOC_ERROR(obd->obd_name, cmd, "karg=null",
					     -EINVAL));
		data = karg;

		memcpy(&index, data->ioc_inlbuf2, sizeof(index));
		if (index >= count)
			RETURN(-ENODEV);

		if (!test_bit(index, lov->lov_ost_descs.ltd_tgt_bitmap))
			/* Try again with the next index */
			RETURN(-EAGAIN);

		tgt = lov_tgt(lov, index);
		osc_obd = class_exp2obd(tgt->ltd_exp);
		if (!osc_obd)
			RETURN(-EINVAL);

		imp = osc_obd->u.cli.cl_import;
		if (!tgt->ltd_active && imp->imp_state != LUSTRE_IMP_IDLE)
			RETURN(-ENODATA);

		/* copy UUID */
		if (copy_to_user(data->ioc_pbuf2, obd2cli_tgt(osc_obd),
				 min_t(unsigned long, data->ioc_plen2,
				       sizeof(struct obd_uuid))))
			RETURN(-EFAULT);

		memcpy(&flags, data->ioc_inlbuf1, sizeof(flags));
		flags = flags & LL_STATFS_NODELAY ? OBD_STATFS_NODELAY : 0;

		/* got statfs data */
		rc = obd_statfs(NULL, tgt->ltd_exp, &stat_buf,
				ktime_get_seconds() - OBD_STATFS_CACHE_SECONDS,
				flags);
		if (rc)
			RETURN(rc);
		if (copy_to_user(data->ioc_pbuf1, &stat_buf,
				 min_t(unsigned long, data->ioc_plen1,
				       sizeof(struct obd_statfs))))
			RETURN(-EFAULT);
		break;
	}
	case OBD_IOC_QUOTACTL: {
		struct if_quotactl *qctl;
		struct obd_quotactl *oqctl;
		struct obd_import *imp;

		if (unlikely(karg == NULL))
			RETURN(OBD_IOC_ERROR(obd->obd_name, cmd, "karg=null",
					     -EINVAL));
		qctl = karg;

		if (qctl->qc_valid == QC_OSTIDX) {
			if (count <= qctl->qc_idx)
				RETURN(-EINVAL);

			if (!test_bit(qctl->qc_idx,
				      lov->lov_ost_descs.ltd_tgt_bitmap))
				RETURN(-ENODEV);

			tgt = lov_tgt(lov, qctl->qc_idx);
			if (!tgt->ltd_exp)
				RETURN(-EINVAL);
		} else if (qctl->qc_valid == QC_UUID) {
			lov_foreach_tgt(lov, tgt) {
				if (!obd_uuid_equals(&tgt->ltd_uuid,
						     &qctl->obd_uuid))
					continue;

				if (!tgt->ltd_exp)
					RETURN(-EINVAL);

				break;
			}
		} else {
			RETURN(-EINVAL);
		}

		if (!tgt || tgt->ltd_index >= count)
			RETURN(-EAGAIN);

		LASSERT(tgt && tgt->ltd_exp);
		imp = class_exp2cliimp(tgt->ltd_exp);
		if (!tgt->ltd_active && imp->imp_state != LUSTRE_IMP_IDLE) {
			qctl->qc_valid = QC_OSTIDX;
			qctl->obd_uuid = tgt->ltd_uuid;
			RETURN(-ENODATA);
		}

		OBD_ALLOC_PTR(oqctl);
		if (!oqctl)
			RETURN(-ENOMEM);

		QCTL_COPY(oqctl, qctl);
		rc = obd_quotactl(tgt->ltd_exp, oqctl);
		if (rc == 0) {
			QCTL_COPY_NO_PNAME(qctl, oqctl);
			qctl->qc_valid = QC_OSTIDX;
			qctl->obd_uuid = tgt->ltd_uuid;
		}
		OBD_FREE_PTR(oqctl);
		break;
	}
	case OBD_IOC_FID2PATH: {
		rc = lov_fid2path(lov, len, karg, uarg);
		break;
	}
	default: {
		int set = 0;

		if (count == 0)
			RETURN(-ENOTTY);

		lov_foreach_tgt(lov, tgt) {
			struct obd_device *osc_obd;
			int err;

			/* OST was disconnected */
			if (!tgt->ltd_exp)
				continue;

			/* ll_umount_begin() sets force on lov, pass to osc */
			osc_obd = class_exp2obd(tgt->ltd_exp);
			if (osc_obd)
				osc_obd->obd_force = obd->obd_force;
			err = obd_iocontrol(cmd, tgt->ltd_exp,
					    len, karg, uarg);
			if (err) {
				if (tgt->ltd_active) {
					OBD_IOC_DEBUG(err == -ENOTTY ?
						      D_IOCTL : D_WARNING,
						      obd->obd_name, cmd,
						      lov_uuid2str(lov, tgt->ltd_index),
						      err);
					if (!rc)
						rc = err;

					if (err == -ENOTTY)
						break;
				}
			} else {
				set = 1;
			}
		}
		if (!set && !rc)
			rc = -EIO;
		break;
	}
	}

	RETURN(rc);
}

static int lov_get_info(const struct lu_env *env, struct obd_export *exp,
			__u32 keylen, void *key, __u32 *vallen, void *val)
{
	struct obd_device *obd = class_exp2obd(exp);
	struct lu_tgt_descs *ltd = &obd->u.lov.lov_ost_descs;
	struct lov_desc *ld = &ltd->ltd_lov_desc;
	int rc = 0;

	ENTRY;
	if (vallen == NULL || val == NULL)
		RETURN(-EFAULT);

	lov_tgts_getref(obd);

	if (KEY_IS(KEY_MAX_EASIZE)) {
		*((u32 *)val) = exp->exp_connect_data.ocd_max_easize;
	} else if (KEY_IS(KEY_DEFAULT_EASIZE)) {
		u32 def_stripe_count = min_t(u32, ld->ld_default_stripe_count,
					     LOV_MAX_STRIPE_COUNT);

		*((u32 *)val) = lov_mds_md_size(def_stripe_count, LOV_MAGIC_V3);
	} else if (KEY_IS(KEY_TGT_COUNT)) {
		*((int *)val) = ld->ld_tgt_count;
	} else if (KEY_IS(KEY_MAX_PAGES_PER_RPC)) {
		struct lov_tgt_desc *tgt;
		struct client_obd *cli;
		struct obd_import *imp;
		u32 result = 0;

		lov_foreach_tgt(&obd->u.lov, tgt) {
			/* OST was disconnected */
			if (!tgt->ltd_exp)
				continue;

			cli = &tgt->ltd_obd->u.cli;
			imp = cli->cl_import;

			if (imp == NULL || imp->imp_state != LUSTRE_IMP_FULL)
				continue;

			if (result == 0)
				result = cli->cl_max_pages_per_rpc;
			else
				result = min_t(u32, cli->cl_max_pages_per_rpc,
					       result);
		}

		*((u32 *)val) = result;
	} else {
		rc = -EINVAL;
	}

	lov_tgts_putref(obd);

	RETURN(rc);
}

static int lov_set_info_async(const struct lu_env *env, struct obd_export *exp,
			      __u32 keylen, void *key,
			      __u32 vallen, void *val,
			      struct ptlrpc_request_set *set)
{
	struct obd_device *obd = class_exp2obd(exp);
	struct lov_obd *lov = &obd->u.lov;
	struct lov_tgt_desc *tgt;
	bool do_inactive = false, no_set = false;
	u32 i;
	int rc = 0;
	int err;

	ENTRY;
	if (set == NULL) {
		no_set = true;
		set = ptlrpc_prep_set();
		if (!set)
			RETURN(-ENOMEM);
	}

	lov_tgts_getref(obd);

	if (KEY_IS(KEY_CHECKSUM))
		do_inactive = true;

	lov_foreach_tgt(lov, tgt) {
		/* OST was disconnected */
		if (!tgt->ltd_exp)
			continue;

		/* OST is inactive and we don't want inactive OSCs */
		if (!tgt->ltd_active && !do_inactive)
			continue;

		err = obd_set_info_async(env, tgt->ltd_exp, keylen, key,
					 vallen, val, set);
		if (rc == 0)
			rc = err;
	}

	/* cycle through MDC target for Data-on-MDT */
	for (i = 0; i < LOV_MDC_TGT_MAX; i++) {
		struct obd_device *mdc;

		mdc = lov->lov_mdc_tgts[i].lmtd_mdc;
		if (mdc == NULL)
			continue;

		err = obd_set_info_async(env, mdc->obd_self_export,
					 keylen, key, vallen, val, set);
		if (rc == 0)
			rc = err;
	}

	lov_tgts_putref(obd);
	if (no_set) {
		err = ptlrpc_set_wait(env, set);
		if (rc == 0)
			rc = err;
		ptlrpc_set_destroy(set);
	}
	RETURN(rc);
}

void lov_stripe_lock(struct lov_stripe_md *md)
__acquires(&md->lsm_lock)
{
	LASSERT(md->lsm_lock_owner != current->pid);
	spin_lock(&md->lsm_lock);
	LASSERT(md->lsm_lock_owner == 0);
	md->lsm_lock_owner = current->pid;
}

void lov_stripe_unlock(struct lov_stripe_md *md)
__releases(&md->lsm_lock)
{
	LASSERT(md->lsm_lock_owner == current->pid);
	md->lsm_lock_owner = 0;
	spin_unlock(&md->lsm_lock);
}

static int lov_quotactl(struct obd_device *obd, struct obd_export *exp,
			struct obd_quotactl *oqctl)
{
	struct lov_obd *lov = &obd->u.lov;
	struct lov_tgt_desc *tgt;
	struct lov_pool_desc *pool = NULL;
	struct list_head *lst = NULL;
	__u64 curspace = 0;
	__u64 bhardlimit = 0;
	int rc = 0;

	ENTRY;
	if (oqctl->qc_cmd != Q_GETOQUOTA &&
	    oqctl->qc_cmd != LUSTRE_Q_SETQUOTA &&
	    oqctl->qc_cmd != LUSTRE_Q_GETQUOTAPOOL &&
	    oqctl->qc_cmd != LUSTRE_Q_ITEROQUOTA) {
		rc = -EFAULT;
		CERROR("%s: bad quota opc %x for lov obd: rc = %d\n",
		       obd->obd_name, oqctl->qc_cmd, rc);
		RETURN(rc);
	}

	if (oqctl->qc_cmd == LUSTRE_Q_GETQUOTAPOOL) {
		pool = lov_pool_find(obd, oqctl->qc_poolname);
		if (!pool)
			RETURN(-ENOENT);
		/* Set Q_GETOQUOTA back as targets report it's own
		 * usage and doesn't care about pools */
		oqctl->qc_cmd = Q_GETOQUOTA;
	}

	if (oqctl->qc_cmd == LUSTRE_Q_ITEROQUOTA)
		lst = (struct list_head *)(uintptr_t)(oqctl->qc_iter_list);

	/* for lov tgt */
	lov_tgts_getref(obd);
	lov_foreach_tgt(lov, tgt) {
		int err;

		if (pool &&
		    lu_tgt_check_index(tgt->ltd_index, &pool->pool_obds))
			continue;

		if (!tgt->ltd_active || tgt->ltd_reap) {
			if (oqctl->qc_cmd == Q_GETOQUOTA &&
			    tgt->ltd_activate) {
				rc = -ENETDOWN;
				CERROR("%s: ost %d is inactive: rc = %d\n",
				       obd->obd_name, tgt->ltd_index, rc);
			} else {
				CDEBUG(D_HA, "ost %d is inactive\n",
				       tgt->ltd_index);
			}
			continue;
		}

		if (oqctl->qc_cmd == LUSTRE_Q_ITEROQUOTA)
			err = obd_quota_iter(tgt->ltd_exp, oqctl, lst);
		else
			err = obd_quotactl(tgt->ltd_exp, oqctl);

		if (err) {
			if (tgt->ltd_active && !rc)
				rc = err;
			continue;
		}

		if (oqctl->qc_cmd == Q_GETOQUOTA) {
			curspace += oqctl->qc_dqblk.dqb_curspace;
			bhardlimit += oqctl->qc_dqblk.dqb_bhardlimit;
		}
	}
	lov_tgts_putref(obd);
	if (pool)
		lov_pool_putref(pool);

	if (oqctl->qc_cmd == Q_GETOQUOTA) {
		oqctl->qc_dqblk.dqb_curspace = curspace;
		oqctl->qc_dqblk.dqb_bhardlimit = bhardlimit;
	}

	RETURN(rc);
}

static const struct obd_ops lov_obd_ops = {
	.o_owner		= THIS_MODULE,
	.o_connect		= lov_connect,
	.o_disconnect		= lov_disconnect,
	.o_statfs		= lov_statfs,
	.o_iocontrol		= lov_iocontrol,
	.o_get_info		= lov_get_info,
	.o_set_info_async	= lov_set_info_async,
	.o_notify		= lov_notify,
	.o_pool_new		= lov_pool_new,
	.o_pool_rem		= lov_pool_remove,
	.o_pool_add		= lov_pool_add,
	.o_pool_del		= lov_pool_del,
	.o_quotactl		= lov_quotactl,
};

struct kmem_cache *lov_oinfo_slab;

static int __init lov_init(void)
{
	int rc;
	ENTRY;

	/* print an address of _any_ initialized kernel symbol from this
	 * module, to allow debugging with gdb that doesn't support data
	 * symbols from modules.*/
	CDEBUG(D_INFO, "Lustre LOV module (%p).\n", &lov_caches);

	rc = libcfs_setup();
	if (rc)
		return rc;

	rc = lu_kmem_init(lov_caches);
	if (rc)
		return rc;

	lov_oinfo_slab = kmem_cache_create("lov_oinfo",
					   sizeof(struct lov_oinfo), 0,
					   SLAB_HWCACHE_ALIGN, NULL);
	if (lov_oinfo_slab == NULL) {
		lu_kmem_fini(lov_caches);
		return -ENOMEM;
	}

	rc = class_register_type(&lov_obd_ops, NULL, true,
				 LUSTRE_LOV_NAME, &lov_device_type);
	if (rc) {
		kmem_cache_destroy(lov_oinfo_slab);
		lu_kmem_fini(lov_caches);
	}

	RETURN(rc);
}

static void __exit lov_exit(void)
{
	class_unregister_type(LUSTRE_LOV_NAME);
	kmem_cache_destroy(lov_oinfo_slab);
	lu_kmem_fini(lov_caches);
}

MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
MODULE_DESCRIPTION("Lustre Logical Object Volume");
MODULE_VERSION(LUSTRE_VERSION_STRING);
MODULE_LICENSE("GPL");

module_init(lov_init);
module_exit(lov_exit);
