staging: lustre: delete the filesystem from the tree.

The Lustre filesystem has been in the kernel tree for over 5 years now.
While it has been an endless source of enjoyment for new kernel
developers learning how to do basic codingstyle cleanups, as well as an
semi-entertaining source of bewilderment from the vfs developers any
time they have looked into the codebase to try to figure out how to port
their latest api changes to this filesystem, it has not really moved
forward into the "this is in shape to get out of staging" despite many
half-completed attempts.

And getting code out of staging is the main goal of that portion of the
kernel tree.  Code should not stagnate and it feels like having this
code in staging is only causing the development cycle of the filesystem
to take longer than it should.  There is a whole separate out-of-tree
copy of this codebase where the developers work on it, and then random
changes are thrown over the wall at staging at some later point in time.
This dual-tree development model has never worked, and the state of this
codebase is proof of that.

So, let's just delete the whole mess.  Now the lustre developers can go
off and work in their out-of-tree codebase and not have to worry about
providing valid changelog entries and breaking their patches up into
logical pieces.  They can take the time they have spend doing those
types of housekeeping chores and get the codebase into a much better
shape, and it can be submitted for inclusion into the real part of the
kernel tree when ready.

Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 0 insertions, 2065 deletions

diff --git a/drivers/staging/lustre/lnet/libcfs/hash.c b/drivers/staging/lustre/lnet/libcfs/hash.c
deleted file mode 100644
index 48be66f0d654..000000000000
--- a/drivers/staging/lustre/lnet/libcfs/hash.c
+++ /dev/null
@@ -1,2065 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * 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.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) 2011, 2012, Intel Corporation.
- */
-/*
- * This file is part of Lustre, http://www.lustre.org/
- * Lustre is a trademark of Sun Microsystems, Inc.
- *
- * libcfs/libcfs/hash.c
- *
- * Implement a hash class for hash process in lustre system.
- *
- * Author: YuZhangyong <yzy@clusterfs.com>
- *
- * 2008-08-15: Brian Behlendorf <behlendorf1@llnl.gov>
- * - Simplified API and improved documentation
- * - Added per-hash feature flags:
- *   * CFS_HASH_DEBUG additional validation
- *   * CFS_HASH_REHASH dynamic rehashing
- * - Added per-hash statistics
- * - General performance enhancements
- *
- * 2009-07-31: Liang Zhen <zhen.liang@sun.com>
- * - move all stuff to libcfs
- * - don't allow cur_bits != max_bits without setting of CFS_HASH_REHASH
- * - ignore hs_rwlock if without CFS_HASH_REHASH setting
- * - buckets are allocated one by one(instead of contiguous memory),
- *   to avoid unnecessary cacheline conflict
- *
- * 2010-03-01: Liang Zhen <zhen.liang@sun.com>
- * - "bucket" is a group of hlist_head now, user can specify bucket size
- *   by bkt_bits of cfs_hash_create(), all hlist_heads in a bucket share
- *   one lock for reducing memory overhead.
- *
- * - support lockless hash, caller will take care of locks:
- *   avoid lock overhead for hash tables that are already protected
- *   by locking in the caller for another reason
- *
- * - support both spin_lock/rwlock for bucket:
- *   overhead of spinlock contention is lower than read/write
- *   contention of rwlock, so using spinlock to serialize operations on
- *   bucket is more reasonable for those frequently changed hash tables
- *
- * - support one-single lock mode:
- *   one lock to protect all hash operations to avoid overhead of
- *   multiple locks if hash table is always small
- *
- * - removed a lot of unnecessary addref & decref on hash element:
- *   addref & decref are atomic operations in many use-cases which
- *   are expensive.
- *
- * - support non-blocking cfs_hash_add() and cfs_hash_findadd():
- *   some lustre use-cases require these functions to be strictly
- *   non-blocking, we need to schedule required rehash on a different
- *   thread on those cases.
- *
- * - safer rehash on large hash table
- *   In old implementation, rehash function will exclusively lock the
- *   hash table and finish rehash in one batch, it's dangerous on SMP
- *   system because rehash millions of elements could take long time.
- *   New implemented rehash can release lock and relax CPU in middle
- *   of rehash, it's safe for another thread to search/change on the
- *   hash table even it's in rehasing.
- *
- * - support two different refcount modes
- *   . hash table has refcount on element
- *   . hash table doesn't change refcount on adding/removing element
- *
- * - support long name hash table (for param-tree)
- *
- * - fix a bug for cfs_hash_rehash_key:
- *   in old implementation, cfs_hash_rehash_key could screw up the
- *   hash-table because @key is overwritten without any protection.
- *   Now we need user to define hs_keycpy for those rehash enabled
- *   hash tables, cfs_hash_rehash_key will overwrite hash-key
- *   inside lock by calling hs_keycpy.
- *
- * - better hash iteration:
- *   Now we support both locked iteration & lockless iteration of hash
- *   table. Also, user can break the iteration by return 1 in callback.
- */
-#include <linux/seq_file.h>
-#include <linux/log2.h>
-#include <linux/slab.h>
-#include <linux/mm.h>
-#include <linux/libcfs/libcfs_hash.h>
-
-#if CFS_HASH_DEBUG_LEVEL >= CFS_HASH_DEBUG_1
-static unsigned int warn_on_depth = 8;
-module_param(warn_on_depth, uint, 0644);
-MODULE_PARM_DESC(warn_on_depth, "warning when hash depth is high.");
-#endif
-
-struct workqueue_struct *cfs_rehash_wq;
-
-static inline void
-cfs_hash_nl_lock(union cfs_hash_lock *lock, int exclusive) {}
-
-static inline void
-cfs_hash_nl_unlock(union cfs_hash_lock *lock, int exclusive) {}
-
-static inline void
-cfs_hash_spin_lock(union cfs_hash_lock *lock, int exclusive)
-	__acquires(&lock->spin)
-{
-	spin_lock(&lock->spin);
-}
-
-static inline void
-cfs_hash_spin_unlock(union cfs_hash_lock *lock, int exclusive)
-	__releases(&lock->spin)
-{
-	spin_unlock(&lock->spin);
-}
-
-static inline void
-cfs_hash_rw_lock(union cfs_hash_lock *lock, int exclusive)
-	__acquires(&lock->rw)
-{
-	if (!exclusive)
-		read_lock(&lock->rw);
-	else
-		write_lock(&lock->rw);
-}
-
-static inline void
-cfs_hash_rw_unlock(union cfs_hash_lock *lock, int exclusive)
-	__releases(&lock->rw)
-{
-	if (!exclusive)
-		read_unlock(&lock->rw);
-	else
-		write_unlock(&lock->rw);
-}
-
-/** No lock hash */
-static struct cfs_hash_lock_ops cfs_hash_nl_lops = {
-	.hs_lock	= cfs_hash_nl_lock,
-	.hs_unlock	= cfs_hash_nl_unlock,
-	.hs_bkt_lock	= cfs_hash_nl_lock,
-	.hs_bkt_unlock	= cfs_hash_nl_unlock,
-};
-
-/** no bucket lock, one spinlock to protect everything */
-static struct cfs_hash_lock_ops cfs_hash_nbl_lops = {
-	.hs_lock	= cfs_hash_spin_lock,
-	.hs_unlock	= cfs_hash_spin_unlock,
-	.hs_bkt_lock	= cfs_hash_nl_lock,
-	.hs_bkt_unlock	= cfs_hash_nl_unlock,
-};
-
-/** spin bucket lock, rehash is enabled */
-static struct cfs_hash_lock_ops cfs_hash_bkt_spin_lops = {
-	.hs_lock	= cfs_hash_rw_lock,
-	.hs_unlock	= cfs_hash_rw_unlock,
-	.hs_bkt_lock	= cfs_hash_spin_lock,
-	.hs_bkt_unlock	= cfs_hash_spin_unlock,
-};
-
-/** rw bucket lock, rehash is enabled */
-static struct cfs_hash_lock_ops cfs_hash_bkt_rw_lops = {
-	.hs_lock	= cfs_hash_rw_lock,
-	.hs_unlock	= cfs_hash_rw_unlock,
-	.hs_bkt_lock	= cfs_hash_rw_lock,
-	.hs_bkt_unlock	= cfs_hash_rw_unlock,
-};
-
-/** spin bucket lock, rehash is disabled */
-static struct cfs_hash_lock_ops cfs_hash_nr_bkt_spin_lops = {
-	.hs_lock	= cfs_hash_nl_lock,
-	.hs_unlock	= cfs_hash_nl_unlock,
-	.hs_bkt_lock	= cfs_hash_spin_lock,
-	.hs_bkt_unlock	= cfs_hash_spin_unlock,
-};
-
-/** rw bucket lock, rehash is disabled */
-static struct cfs_hash_lock_ops cfs_hash_nr_bkt_rw_lops = {
-	.hs_lock	= cfs_hash_nl_lock,
-	.hs_unlock	= cfs_hash_nl_unlock,
-	.hs_bkt_lock	= cfs_hash_rw_lock,
-	.hs_bkt_unlock	= cfs_hash_rw_unlock,
-};
-
-static void
-cfs_hash_lock_setup(struct cfs_hash *hs)
-{
-	if (cfs_hash_with_no_lock(hs)) {
-		hs->hs_lops = &cfs_hash_nl_lops;
-
-	} else if (cfs_hash_with_no_bktlock(hs)) {
-		hs->hs_lops = &cfs_hash_nbl_lops;
-		spin_lock_init(&hs->hs_lock.spin);
-
-	} else if (cfs_hash_with_rehash(hs)) {
-		rwlock_init(&hs->hs_lock.rw);
-
-		if (cfs_hash_with_rw_bktlock(hs))
-			hs->hs_lops = &cfs_hash_bkt_rw_lops;
-		else if (cfs_hash_with_spin_bktlock(hs))
-			hs->hs_lops = &cfs_hash_bkt_spin_lops;
-		else
-			LBUG();
-	} else {
-		if (cfs_hash_with_rw_bktlock(hs))
-			hs->hs_lops = &cfs_hash_nr_bkt_rw_lops;
-		else if (cfs_hash_with_spin_bktlock(hs))
-			hs->hs_lops = &cfs_hash_nr_bkt_spin_lops;
-		else
-			LBUG();
-	}
-}
-
-/**
- * Simple hash head without depth tracking
- * new element is always added to head of hlist
- */
-struct cfs_hash_head {
-	struct hlist_head	hh_head;	/**< entries list */
-};
-
-static int
-cfs_hash_hh_hhead_size(struct cfs_hash *hs)
-{
-	return sizeof(struct cfs_hash_head);
-}
-
-static struct hlist_head *
-cfs_hash_hh_hhead(struct cfs_hash *hs, struct cfs_hash_bd *bd)
-{
-	struct cfs_hash_head *head;
-
-	head = (struct cfs_hash_head *)&bd->bd_bucket->hsb_head[0];
-	return &head[bd->bd_offset].hh_head;
-}
-
-static int
-cfs_hash_hh_hnode_add(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnode)
-{
-	hlist_add_head(hnode, cfs_hash_hh_hhead(hs, bd));
-	return -1; /* unknown depth */
-}
-
-static int
-cfs_hash_hh_hnode_del(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnode)
-{
-	hlist_del_init(hnode);
-	return -1; /* unknown depth */
-}
-
-/**
- * Simple hash head with depth tracking
- * new element is always added to head of hlist
- */
-struct cfs_hash_head_dep {
-	struct hlist_head	hd_head;	/**< entries list */
-	unsigned int		hd_depth;	/**< list length */
-};
-
-static int
-cfs_hash_hd_hhead_size(struct cfs_hash *hs)
-{
-	return sizeof(struct cfs_hash_head_dep);
-}
-
-static struct hlist_head *
-cfs_hash_hd_hhead(struct cfs_hash *hs, struct cfs_hash_bd *bd)
-{
-	struct cfs_hash_head_dep *head;
-
-	head = (struct cfs_hash_head_dep *)&bd->bd_bucket->hsb_head[0];
-	return &head[bd->bd_offset].hd_head;
-}
-
-static int
-cfs_hash_hd_hnode_add(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnode)
-{
-	struct cfs_hash_head_dep *hh;
-
-	hh = container_of(cfs_hash_hd_hhead(hs, bd),
-			  struct cfs_hash_head_dep, hd_head);
-	hlist_add_head(hnode, &hh->hd_head);
-	return ++hh->hd_depth;
-}
-
-static int
-cfs_hash_hd_hnode_del(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnode)
-{
-	struct cfs_hash_head_dep *hh;
-
-	hh = container_of(cfs_hash_hd_hhead(hs, bd),
-			  struct cfs_hash_head_dep, hd_head);
-	hlist_del_init(hnode);
-	return --hh->hd_depth;
-}
-
-/**
- * double links hash head without depth tracking
- * new element is always added to tail of hlist
- */
-struct cfs_hash_dhead {
-	struct hlist_head	dh_head;	/**< entries list */
-	struct hlist_node	*dh_tail;	/**< the last entry */
-};
-
-static int
-cfs_hash_dh_hhead_size(struct cfs_hash *hs)
-{
-	return sizeof(struct cfs_hash_dhead);
-}
-
-static struct hlist_head *
-cfs_hash_dh_hhead(struct cfs_hash *hs, struct cfs_hash_bd *bd)
-{
-	struct cfs_hash_dhead *head;
-
-	head = (struct cfs_hash_dhead *)&bd->bd_bucket->hsb_head[0];
-	return &head[bd->bd_offset].dh_head;
-}
-
-static int
-cfs_hash_dh_hnode_add(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnode)
-{
-	struct cfs_hash_dhead *dh;
-
-	dh = container_of(cfs_hash_dh_hhead(hs, bd),
-			  struct cfs_hash_dhead, dh_head);
-	if (dh->dh_tail) /* not empty */
-		hlist_add_behind(hnode, dh->dh_tail);
-	else /* empty list */
-		hlist_add_head(hnode, &dh->dh_head);
-	dh->dh_tail = hnode;
-	return -1; /* unknown depth */
-}
-
-static int
-cfs_hash_dh_hnode_del(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnd)
-{
-	struct cfs_hash_dhead *dh;
-
-	dh = container_of(cfs_hash_dh_hhead(hs, bd),
-			  struct cfs_hash_dhead, dh_head);
-	if (!hnd->next) { /* it's the tail */
-		dh->dh_tail = (hnd->pprev == &dh->dh_head.first) ? NULL :
-			      container_of(hnd->pprev, struct hlist_node, next);
-	}
-	hlist_del_init(hnd);
-	return -1; /* unknown depth */
-}
-
-/**
- * double links hash head with depth tracking
- * new element is always added to tail of hlist
- */
-struct cfs_hash_dhead_dep {
-	struct hlist_head	dd_head;	/**< entries list */
-	struct hlist_node	*dd_tail;	/**< the last entry */
-	unsigned int		dd_depth;	/**< list length */
-};
-
-static int
-cfs_hash_dd_hhead_size(struct cfs_hash *hs)
-{
-	return sizeof(struct cfs_hash_dhead_dep);
-}
-
-static struct hlist_head *
-cfs_hash_dd_hhead(struct cfs_hash *hs, struct cfs_hash_bd *bd)
-{
-	struct cfs_hash_dhead_dep *head;
-
-	head = (struct cfs_hash_dhead_dep *)&bd->bd_bucket->hsb_head[0];
-	return &head[bd->bd_offset].dd_head;
-}
-
-static int
-cfs_hash_dd_hnode_add(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnode)
-{
-	struct cfs_hash_dhead_dep *dh;
-
-	dh = container_of(cfs_hash_dd_hhead(hs, bd),
-			  struct cfs_hash_dhead_dep, dd_head);
-	if (dh->dd_tail) /* not empty */
-		hlist_add_behind(hnode, dh->dd_tail);
-	else /* empty list */
-		hlist_add_head(hnode, &dh->dd_head);
-	dh->dd_tail = hnode;
-	return ++dh->dd_depth;
-}
-
-static int
-cfs_hash_dd_hnode_del(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		      struct hlist_node *hnd)
-{
-	struct cfs_hash_dhead_dep *dh;
-
-	dh = container_of(cfs_hash_dd_hhead(hs, bd),
-			  struct cfs_hash_dhead_dep, dd_head);
-	if (!hnd->next) { /* it's the tail */
-		dh->dd_tail = (hnd->pprev == &dh->dd_head.first) ? NULL :
-			      container_of(hnd->pprev, struct hlist_node, next);
-	}
-	hlist_del_init(hnd);
-	return --dh->dd_depth;
-}
-
-static struct cfs_hash_hlist_ops cfs_hash_hh_hops = {
-	.hop_hhead	= cfs_hash_hh_hhead,
-	.hop_hhead_size	= cfs_hash_hh_hhead_size,
-	.hop_hnode_add	= cfs_hash_hh_hnode_add,
-	.hop_hnode_del	= cfs_hash_hh_hnode_del,
-};
-
-static struct cfs_hash_hlist_ops cfs_hash_hd_hops = {
-	.hop_hhead	= cfs_hash_hd_hhead,
-	.hop_hhead_size	= cfs_hash_hd_hhead_size,
-	.hop_hnode_add	= cfs_hash_hd_hnode_add,
-	.hop_hnode_del	= cfs_hash_hd_hnode_del,
-};
-
-static struct cfs_hash_hlist_ops cfs_hash_dh_hops = {
-	.hop_hhead	= cfs_hash_dh_hhead,
-	.hop_hhead_size	= cfs_hash_dh_hhead_size,
-	.hop_hnode_add	= cfs_hash_dh_hnode_add,
-	.hop_hnode_del	= cfs_hash_dh_hnode_del,
-};
-
-static struct cfs_hash_hlist_ops cfs_hash_dd_hops = {
-	.hop_hhead	= cfs_hash_dd_hhead,
-	.hop_hhead_size	= cfs_hash_dd_hhead_size,
-	.hop_hnode_add	= cfs_hash_dd_hnode_add,
-	.hop_hnode_del	= cfs_hash_dd_hnode_del,
-};
-
-static void
-cfs_hash_hlist_setup(struct cfs_hash *hs)
-{
-	if (cfs_hash_with_add_tail(hs)) {
-		hs->hs_hops = cfs_hash_with_depth(hs) ?
-			      &cfs_hash_dd_hops : &cfs_hash_dh_hops;
-	} else {
-		hs->hs_hops = cfs_hash_with_depth(hs) ?
-			      &cfs_hash_hd_hops : &cfs_hash_hh_hops;
-	}
-}
-
-static void
-cfs_hash_bd_from_key(struct cfs_hash *hs, struct cfs_hash_bucket **bkts,
-		     unsigned int bits, const void *key, struct cfs_hash_bd *bd)
-{
-	unsigned int index = cfs_hash_id(hs, key, (1U << bits) - 1);
-
-	LASSERT(bits == hs->hs_cur_bits || bits == hs->hs_rehash_bits);
-
-	bd->bd_bucket = bkts[index & ((1U << (bits - hs->hs_bkt_bits)) - 1)];
-	bd->bd_offset = index >> (bits - hs->hs_bkt_bits);
-}
-
-void
-cfs_hash_bd_get(struct cfs_hash *hs, const void *key, struct cfs_hash_bd *bd)
-{
-	/* NB: caller should hold hs->hs_rwlock if REHASH is set */
-	if (likely(!hs->hs_rehash_buckets)) {
-		cfs_hash_bd_from_key(hs, hs->hs_buckets,
-				     hs->hs_cur_bits, key, bd);
-	} else {
-		LASSERT(hs->hs_rehash_bits);
-		cfs_hash_bd_from_key(hs, hs->hs_rehash_buckets,
-				     hs->hs_rehash_bits, key, bd);
-	}
-}
-EXPORT_SYMBOL(cfs_hash_bd_get);
-
-static inline void
-cfs_hash_bd_dep_record(struct cfs_hash *hs, struct cfs_hash_bd *bd, int dep_cur)
-{
-	if (likely(dep_cur <= bd->bd_bucket->hsb_depmax))
-		return;
-
-	bd->bd_bucket->hsb_depmax = dep_cur;
-# if CFS_HASH_DEBUG_LEVEL >= CFS_HASH_DEBUG_1
-	if (likely(!warn_on_depth ||
-		   max(warn_on_depth, hs->hs_dep_max) >= dep_cur))
-		return;
-
-	spin_lock(&hs->hs_dep_lock);
-	hs->hs_dep_max = dep_cur;
-	hs->hs_dep_bkt = bd->bd_bucket->hsb_index;
-	hs->hs_dep_off = bd->bd_offset;
-	hs->hs_dep_bits = hs->hs_cur_bits;
-	spin_unlock(&hs->hs_dep_lock);
-
-	queue_work(cfs_rehash_wq, &hs->hs_dep_work);
-# endif
-}
-
-void
-cfs_hash_bd_add_locked(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		       struct hlist_node *hnode)
-{
-	int rc;
-
-	rc = hs->hs_hops->hop_hnode_add(hs, bd, hnode);
-	cfs_hash_bd_dep_record(hs, bd, rc);
-	bd->bd_bucket->hsb_version++;
-	if (unlikely(!bd->bd_bucket->hsb_version))
-		bd->bd_bucket->hsb_version++;
-	bd->bd_bucket->hsb_count++;
-
-	if (cfs_hash_with_counter(hs))
-		atomic_inc(&hs->hs_count);
-	if (!cfs_hash_with_no_itemref(hs))
-		cfs_hash_get(hs, hnode);
-}
-EXPORT_SYMBOL(cfs_hash_bd_add_locked);
-
-void
-cfs_hash_bd_del_locked(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-		       struct hlist_node *hnode)
-{
-	hs->hs_hops->hop_hnode_del(hs, bd, hnode);
-
-	LASSERT(bd->bd_bucket->hsb_count > 0);
-	bd->bd_bucket->hsb_count--;
-	bd->bd_bucket->hsb_version++;
-	if (unlikely(!bd->bd_bucket->hsb_version))
-		bd->bd_bucket->hsb_version++;
-
-	if (cfs_hash_with_counter(hs)) {
-		LASSERT(atomic_read(&hs->hs_count) > 0);
-		atomic_dec(&hs->hs_count);
-	}
-	if (!cfs_hash_with_no_itemref(hs))
-		cfs_hash_put_locked(hs, hnode);
-}
-EXPORT_SYMBOL(cfs_hash_bd_del_locked);
-
-void
-cfs_hash_bd_move_locked(struct cfs_hash *hs, struct cfs_hash_bd *bd_old,
-			struct cfs_hash_bd *bd_new, struct hlist_node *hnode)
-{
-	struct cfs_hash_bucket *obkt = bd_old->bd_bucket;
-	struct cfs_hash_bucket *nbkt = bd_new->bd_bucket;
-	int rc;
-
-	if (!cfs_hash_bd_compare(bd_old, bd_new))
-		return;
-
-	/* use cfs_hash_bd_hnode_add/del, to avoid atomic & refcount ops
-	 * in cfs_hash_bd_del/add_locked
-	 */
-	hs->hs_hops->hop_hnode_del(hs, bd_old, hnode);
-	rc = hs->hs_hops->hop_hnode_add(hs, bd_new, hnode);
-	cfs_hash_bd_dep_record(hs, bd_new, rc);
-
-	LASSERT(obkt->hsb_count > 0);
-	obkt->hsb_count--;
-	obkt->hsb_version++;
-	if (unlikely(!obkt->hsb_version))
-		obkt->hsb_version++;
-	nbkt->hsb_count++;
-	nbkt->hsb_version++;
-	if (unlikely(!nbkt->hsb_version))
-		nbkt->hsb_version++;
-}
-
-enum {
-	/** always set, for sanity (avoid ZERO intent) */
-	CFS_HS_LOOKUP_MASK_FIND	= BIT(0),
-	/** return entry with a ref */
-	CFS_HS_LOOKUP_MASK_REF	= BIT(1),
-	/** add entry if not existing */
-	CFS_HS_LOOKUP_MASK_ADD	= BIT(2),
-	/** delete entry, ignore other masks */
-	CFS_HS_LOOKUP_MASK_DEL	= BIT(3),
-};
-
-enum cfs_hash_lookup_intent {
-	/** return item w/o refcount */
-	CFS_HS_LOOKUP_IT_PEEK	 = CFS_HS_LOOKUP_MASK_FIND,
-	/** return item with refcount */
-	CFS_HS_LOOKUP_IT_FIND	 = (CFS_HS_LOOKUP_MASK_FIND |
-				    CFS_HS_LOOKUP_MASK_REF),
-	/** return item w/o refcount if existed, otherwise add */
-	CFS_HS_LOOKUP_IT_ADD	 = (CFS_HS_LOOKUP_MASK_FIND |
-				    CFS_HS_LOOKUP_MASK_ADD),
-	/** return item with refcount if existed, otherwise add */
-	CFS_HS_LOOKUP_IT_FINDADD = (CFS_HS_LOOKUP_IT_FIND |
-				    CFS_HS_LOOKUP_MASK_ADD),
-	/** delete if existed */
-	CFS_HS_LOOKUP_IT_FINDDEL = (CFS_HS_LOOKUP_MASK_FIND |
-				    CFS_HS_LOOKUP_MASK_DEL)
-};
-
-static struct hlist_node *
-cfs_hash_bd_lookup_intent(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-			  const void *key, struct hlist_node *hnode,
-			  enum cfs_hash_lookup_intent intent)
-
-{
-	struct hlist_head *hhead = cfs_hash_bd_hhead(hs, bd);
-	struct hlist_node *ehnode;
-	struct hlist_node *match;
-	int intent_add = intent & CFS_HS_LOOKUP_MASK_ADD;
-
-	/* with this function, we can avoid a lot of useless refcount ops,
-	 * which are expensive atomic operations most time.
-	 */
-	match = intent_add ? NULL : hnode;
-	hlist_for_each(ehnode, hhead) {
-		if (!cfs_hash_keycmp(hs, key, ehnode))
-			continue;
-
-		if (match && match != ehnode) /* can't match */
-			continue;
-
-		/* match and ... */
-		if (intent & CFS_HS_LOOKUP_MASK_DEL) {
-			cfs_hash_bd_del_locked(hs, bd, ehnode);
-			return ehnode;
-		}
-
-		/* caller wants refcount? */
-		if (intent & CFS_HS_LOOKUP_MASK_REF)
-			cfs_hash_get(hs, ehnode);
-		return ehnode;
-	}
-	/* no match item */
-	if (!intent_add)
-		return NULL;
-
-	LASSERT(hnode);
-	cfs_hash_bd_add_locked(hs, bd, hnode);
-	return hnode;
-}
-
-struct hlist_node *
-cfs_hash_bd_lookup_locked(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-			  const void *key)
-{
-	return cfs_hash_bd_lookup_intent(hs, bd, key, NULL,
-					 CFS_HS_LOOKUP_IT_FIND);
-}
-EXPORT_SYMBOL(cfs_hash_bd_lookup_locked);
-
-struct hlist_node *
-cfs_hash_bd_peek_locked(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-			const void *key)
-{
-	return cfs_hash_bd_lookup_intent(hs, bd, key, NULL,
-					 CFS_HS_LOOKUP_IT_PEEK);
-}
-EXPORT_SYMBOL(cfs_hash_bd_peek_locked);
-
-static void
-cfs_hash_multi_bd_lock(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-		       unsigned int n, int excl)
-{
-	struct cfs_hash_bucket *prev = NULL;
-	int i;
-
-	/**
-	 * bds must be ascendantly ordered by bd->bd_bucket->hsb_index.
-	 * NB: it's possible that several bds point to the same bucket but
-	 * have different bd::bd_offset, so need take care of deadlock.
-	 */
-	cfs_hash_for_each_bd(bds, n, i) {
-		if (prev == bds[i].bd_bucket)
-			continue;
-
-		LASSERT(!prev || prev->hsb_index < bds[i].bd_bucket->hsb_index);
-		cfs_hash_bd_lock(hs, &bds[i], excl);
-		prev = bds[i].bd_bucket;
-	}
-}
-
-static void
-cfs_hash_multi_bd_unlock(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-			 unsigned int n, int excl)
-{
-	struct cfs_hash_bucket *prev = NULL;
-	int i;
-
-	cfs_hash_for_each_bd(bds, n, i) {
-		if (prev != bds[i].bd_bucket) {
-			cfs_hash_bd_unlock(hs, &bds[i], excl);
-			prev = bds[i].bd_bucket;
-		}
-	}
-}
-
-static struct hlist_node *
-cfs_hash_multi_bd_lookup_locked(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-				unsigned int n, const void *key)
-{
-	struct hlist_node *ehnode;
-	unsigned int i;
-
-	cfs_hash_for_each_bd(bds, n, i) {
-		ehnode = cfs_hash_bd_lookup_intent(hs, &bds[i], key, NULL,
-						   CFS_HS_LOOKUP_IT_FIND);
-		if (ehnode)
-			return ehnode;
-	}
-	return NULL;
-}
-
-static struct hlist_node *
-cfs_hash_multi_bd_findadd_locked(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-				 unsigned int n, const void *key,
-				 struct hlist_node *hnode, int noref)
-{
-	struct hlist_node *ehnode;
-	int intent;
-	unsigned int i;
-
-	LASSERT(hnode);
-	intent = (!noref * CFS_HS_LOOKUP_MASK_REF) | CFS_HS_LOOKUP_IT_PEEK;
-
-	cfs_hash_for_each_bd(bds, n, i) {
-		ehnode = cfs_hash_bd_lookup_intent(hs, &bds[i], key,
-						   NULL, intent);
-		if (ehnode)
-			return ehnode;
-	}
-
-	if (i == 1) { /* only one bucket */
-		cfs_hash_bd_add_locked(hs, &bds[0], hnode);
-	} else {
-		struct cfs_hash_bd mybd;
-
-		cfs_hash_bd_get(hs, key, &mybd);
-		cfs_hash_bd_add_locked(hs, &mybd, hnode);
-	}
-
-	return hnode;
-}
-
-static struct hlist_node *
-cfs_hash_multi_bd_finddel_locked(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-				 unsigned int n, const void *key,
-				 struct hlist_node *hnode)
-{
-	struct hlist_node *ehnode;
-	unsigned int i;
-
-	cfs_hash_for_each_bd(bds, n, i) {
-		ehnode = cfs_hash_bd_lookup_intent(hs, &bds[i], key, hnode,
-						   CFS_HS_LOOKUP_IT_FINDDEL);
-		if (ehnode)
-			return ehnode;
-	}
-	return NULL;
-}
-
-static void
-cfs_hash_bd_order(struct cfs_hash_bd *bd1, struct cfs_hash_bd *bd2)
-{
-	int rc;
-
-	if (!bd2->bd_bucket)
-		return;
-
-	if (!bd1->bd_bucket) {
-		*bd1 = *bd2;
-		bd2->bd_bucket = NULL;
-		return;
-	}
-
-	rc = cfs_hash_bd_compare(bd1, bd2);
-	if (!rc)
-		bd2->bd_bucket = NULL;
-	else if (rc > 0)
-		swap(*bd1, *bd2); /* swap bd1 and bd2 */
-}
-
-void
-cfs_hash_dual_bd_get(struct cfs_hash *hs, const void *key,
-		     struct cfs_hash_bd *bds)
-{
-	/* NB: caller should hold hs_lock.rw if REHASH is set */
-	cfs_hash_bd_from_key(hs, hs->hs_buckets,
-			     hs->hs_cur_bits, key, &bds[0]);
-	if (likely(!hs->hs_rehash_buckets)) {
-		/* no rehash or not rehashing */
-		bds[1].bd_bucket = NULL;
-		return;
-	}
-
-	LASSERT(hs->hs_rehash_bits);
-	cfs_hash_bd_from_key(hs, hs->hs_rehash_buckets,
-			     hs->hs_rehash_bits, key, &bds[1]);
-
-	cfs_hash_bd_order(&bds[0], &bds[1]);
-}
-
-void
-cfs_hash_dual_bd_lock(struct cfs_hash *hs, struct cfs_hash_bd *bds, int excl)
-{
-	cfs_hash_multi_bd_lock(hs, bds, 2, excl);
-}
-
-void
-cfs_hash_dual_bd_unlock(struct cfs_hash *hs, struct cfs_hash_bd *bds, int excl)
-{
-	cfs_hash_multi_bd_unlock(hs, bds, 2, excl);
-}
-
-struct hlist_node *
-cfs_hash_dual_bd_lookup_locked(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-			       const void *key)
-{
-	return cfs_hash_multi_bd_lookup_locked(hs, bds, 2, key);
-}
-
-struct hlist_node *
-cfs_hash_dual_bd_findadd_locked(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-				const void *key, struct hlist_node *hnode,
-				int noref)
-{
-	return cfs_hash_multi_bd_findadd_locked(hs, bds, 2, key,
-						hnode, noref);
-}
-
-struct hlist_node *
-cfs_hash_dual_bd_finddel_locked(struct cfs_hash *hs, struct cfs_hash_bd *bds,
-				const void *key, struct hlist_node *hnode)
-{
-	return cfs_hash_multi_bd_finddel_locked(hs, bds, 2, key, hnode);
-}
-
-static void
-cfs_hash_buckets_free(struct cfs_hash_bucket **buckets,
-		      int bkt_size, int prev_size, int size)
-{
-	int i;
-
-	for (i = prev_size; i < size; i++)
-		kfree(buckets[i]);
-
-	kvfree(buckets);
-}
-
-/*
- * Create or grow bucket memory. Return old_buckets if no allocation was
- * needed, the newly allocated buckets if allocation was needed and
- * successful, and NULL on error.
- */
-static struct cfs_hash_bucket **
-cfs_hash_buckets_realloc(struct cfs_hash *hs, struct cfs_hash_bucket **old_bkts,
-			 unsigned int old_size, unsigned int new_size)
-{
-	struct cfs_hash_bucket **new_bkts;
-	int i;
-
-	LASSERT(!old_size || old_bkts);
-
-	if (old_bkts && old_size == new_size)
-		return old_bkts;
-
-	new_bkts = kvmalloc_array(new_size, sizeof(new_bkts[0]), GFP_KERNEL);
-	if (!new_bkts)
-		return NULL;
-
-	if (old_bkts) {
-		memcpy(new_bkts, old_bkts,
-		       min(old_size, new_size) * sizeof(*old_bkts));
-	}
-
-	for (i = old_size; i < new_size; i++) {
-		struct hlist_head *hhead;
-		struct cfs_hash_bd bd;
-
-		new_bkts[i] = kzalloc(cfs_hash_bkt_size(hs), GFP_KERNEL);
-		if (!new_bkts[i]) {
-			cfs_hash_buckets_free(new_bkts, cfs_hash_bkt_size(hs),
-					      old_size, new_size);
-			return NULL;
-		}
-
-		new_bkts[i]->hsb_index = i;
-		new_bkts[i]->hsb_version = 1;	/* shouldn't be zero */
-		new_bkts[i]->hsb_depmax = -1;	/* unknown */
-		bd.bd_bucket = new_bkts[i];
-		cfs_hash_bd_for_each_hlist(hs, &bd, hhead)
-			INIT_HLIST_HEAD(hhead);
-
-		if (cfs_hash_with_no_lock(hs) ||
-		    cfs_hash_with_no_bktlock(hs))
-			continue;
-
-		if (cfs_hash_with_rw_bktlock(hs))
-			rwlock_init(&new_bkts[i]->hsb_lock.rw);
-		else if (cfs_hash_with_spin_bktlock(hs))
-			spin_lock_init(&new_bkts[i]->hsb_lock.spin);
-		else
-			LBUG(); /* invalid use-case */
-	}
-	return new_bkts;
-}
-
-/**
- * Initialize new libcfs hash, where:
- * @name     - Descriptive hash name
- * @cur_bits - Initial hash table size, in bits
- * @max_bits - Maximum allowed hash table resize, in bits
- * @ops      - Registered hash table operations
- * @flags    - CFS_HASH_REHASH enable synamic hash resizing
- *	     - CFS_HASH_SORT enable chained hash sort
- */
-static void cfs_hash_rehash_worker(struct work_struct *work);
-
-#if CFS_HASH_DEBUG_LEVEL >= CFS_HASH_DEBUG_1
-static void cfs_hash_dep_print(struct work_struct *work)
-{
-	struct cfs_hash *hs = container_of(work, struct cfs_hash, hs_dep_work);
-	int dep;
-	int bkt;
-	int off;
-	int bits;
-
-	spin_lock(&hs->hs_dep_lock);
-	dep = hs->hs_dep_max;
-	bkt = hs->hs_dep_bkt;
-	off = hs->hs_dep_off;
-	bits = hs->hs_dep_bits;
-	spin_unlock(&hs->hs_dep_lock);
-
-	LCONSOLE_WARN("#### HASH %s (bits: %d): max depth %d at bucket %d/%d\n",
-		      hs->hs_name, bits, dep, bkt, off);
-	spin_lock(&hs->hs_dep_lock);
-	hs->hs_dep_bits = 0; /* mark as workitem done */
-	spin_unlock(&hs->hs_dep_lock);
-	return 0;
-}
-
-static void cfs_hash_depth_wi_init(struct cfs_hash *hs)
-{
-	spin_lock_init(&hs->hs_dep_lock);
-	INIT_WORK(&hs->hs_dep_work, cfs_hash_dep_print);
-}
-
-static void cfs_hash_depth_wi_cancel(struct cfs_hash *hs)
-{
-	cancel_work_sync(&hs->hs_dep_work);
-}
-
-#else /* CFS_HASH_DEBUG_LEVEL < CFS_HASH_DEBUG_1 */
-
-static inline void cfs_hash_depth_wi_init(struct cfs_hash *hs) {}
-static inline void cfs_hash_depth_wi_cancel(struct cfs_hash *hs) {}
-
-#endif /* CFS_HASH_DEBUG_LEVEL >= CFS_HASH_DEBUG_1 */
-
-struct cfs_hash *
-cfs_hash_create(char *name, unsigned int cur_bits, unsigned int max_bits,
-		unsigned int bkt_bits, unsigned int extra_bytes,
-		unsigned int min_theta, unsigned int max_theta,
-		struct cfs_hash_ops *ops, unsigned int flags)
-{
-	struct cfs_hash *hs;
-	int len;
-
-	BUILD_BUG_ON(CFS_HASH_THETA_BITS >= 15);
-
-	LASSERT(name);
-	LASSERT(ops->hs_key);
-	LASSERT(ops->hs_hash);
-	LASSERT(ops->hs_object);
-	LASSERT(ops->hs_keycmp);
-	LASSERT(ops->hs_get);
-	LASSERT(ops->hs_put || ops->hs_put_locked);
-
-	if (flags & CFS_HASH_REHASH)
-		flags |= CFS_HASH_COUNTER; /* must have counter */
-
-	LASSERT(cur_bits > 0);
-	LASSERT(cur_bits >= bkt_bits);
-	LASSERT(max_bits >= cur_bits && max_bits < 31);
-	LASSERT(ergo(!(flags & CFS_HASH_REHASH), cur_bits == max_bits));
-	LASSERT(ergo(flags & CFS_HASH_REHASH, !(flags & CFS_HASH_NO_LOCK)));
-	LASSERT(ergo(flags & CFS_HASH_REHASH_KEY, ops->hs_keycpy));
-
-	len = !(flags & CFS_HASH_BIGNAME) ?
-	      CFS_HASH_NAME_LEN : CFS_HASH_BIGNAME_LEN;
-	hs = kzalloc(offsetof(struct cfs_hash, hs_name[len]), GFP_KERNEL);
-	if (!hs)
-		return NULL;
-
-	strlcpy(hs->hs_name, name, len);
-	hs->hs_flags = flags;
-
-	atomic_set(&hs->hs_refcount, 1);
-	atomic_set(&hs->hs_count, 0);
-
-	cfs_hash_lock_setup(hs);
-	cfs_hash_hlist_setup(hs);
-
-	hs->hs_cur_bits = (u8)cur_bits;
-	hs->hs_min_bits = (u8)cur_bits;
-	hs->hs_max_bits = (u8)max_bits;
-	hs->hs_bkt_bits = (u8)bkt_bits;
-
-	hs->hs_ops = ops;
-	hs->hs_extra_bytes = extra_bytes;
-	hs->hs_rehash_bits = 0;
-	INIT_WORK(&hs->hs_rehash_work, cfs_hash_rehash_worker);
-	cfs_hash_depth_wi_init(hs);
-
-	if (cfs_hash_with_rehash(hs))
-		__cfs_hash_set_theta(hs, min_theta, max_theta);
-
-	hs->hs_buckets = cfs_hash_buckets_realloc(hs, NULL, 0,
-						  CFS_HASH_NBKT(hs));
-	if (hs->hs_buckets)
-		return hs;
-
-	kfree(hs);
-	return NULL;
-}
-EXPORT_SYMBOL(cfs_hash_create);
-
-/**
- * Cleanup libcfs hash @hs.
- */
-static void
-cfs_hash_destroy(struct cfs_hash *hs)
-{
-	struct hlist_node *hnode;
-	struct hlist_node *pos;
-	struct cfs_hash_bd bd;
-	int i;
-
-	LASSERT(hs);
-	LASSERT(!cfs_hash_is_exiting(hs) &&
-		!cfs_hash_is_iterating(hs));
-
-	/**
-	 * prohibit further rehashes, don't need any lock because
-	 * I'm the only (last) one can change it.
-	 */
-	hs->hs_exiting = 1;
-	if (cfs_hash_with_rehash(hs))
-		cfs_hash_rehash_cancel(hs);
-
-	cfs_hash_depth_wi_cancel(hs);
-	/* rehash should be done/canceled */
-	LASSERT(hs->hs_buckets && !hs->hs_rehash_buckets);
-
-	cfs_hash_for_each_bucket(hs, &bd, i) {
-		struct hlist_head *hhead;
-
-		LASSERT(bd.bd_bucket);
-		/* no need to take this lock, just for consistent code */
-		cfs_hash_bd_lock(hs, &bd, 1);
-
-		cfs_hash_bd_for_each_hlist(hs, &bd, hhead) {
-			hlist_for_each_safe(hnode, pos, hhead) {
-				LASSERTF(!cfs_hash_with_assert_empty(hs),
-					 "hash %s bucket %u(%u) is not empty: %u items left\n",
-					 hs->hs_name, bd.bd_bucket->hsb_index,
-					 bd.bd_offset, bd.bd_bucket->hsb_count);
-				/* can't assert key valicate, because we
-				 * can interrupt rehash
-				 */
-				cfs_hash_bd_del_locked(hs, &bd, hnode);
-				cfs_hash_exit(hs, hnode);
-			}
-		}
-		LASSERT(!bd.bd_bucket->hsb_count);
-		cfs_hash_bd_unlock(hs, &bd, 1);
-		cond_resched();
-	}
-
-	LASSERT(!atomic_read(&hs->hs_count));
-
-	cfs_hash_buckets_free(hs->hs_buckets, cfs_hash_bkt_size(hs),
-			      0, CFS_HASH_NBKT(hs));
-	i = cfs_hash_with_bigname(hs) ?
-	    CFS_HASH_BIGNAME_LEN : CFS_HASH_NAME_LEN;
-	kfree(hs);
-}
-
-struct cfs_hash *cfs_hash_getref(struct cfs_hash *hs)
-{
-	if (atomic_inc_not_zero(&hs->hs_refcount))
-		return hs;
-	return NULL;
-}
-EXPORT_SYMBOL(cfs_hash_getref);
-
-void cfs_hash_putref(struct cfs_hash *hs)
-{
-	if (atomic_dec_and_test(&hs->hs_refcount))
-		cfs_hash_destroy(hs);
-}
-EXPORT_SYMBOL(cfs_hash_putref);
-
-static inline int
-cfs_hash_rehash_bits(struct cfs_hash *hs)
-{
-	if (cfs_hash_with_no_lock(hs) ||
-	    !cfs_hash_with_rehash(hs))
-		return -EOPNOTSUPP;
-
-	if (unlikely(cfs_hash_is_exiting(hs)))
-		return -ESRCH;
-
-	if (unlikely(cfs_hash_is_rehashing(hs)))
-		return -EALREADY;
-
-	if (unlikely(cfs_hash_is_iterating(hs)))
-		return -EAGAIN;
-
-	/* XXX: need to handle case with max_theta != 2.0
-	 *      and the case with min_theta != 0.5
-	 */
-	if ((hs->hs_cur_bits < hs->hs_max_bits) &&
-	    (__cfs_hash_theta(hs) > hs->hs_max_theta))
-		return hs->hs_cur_bits + 1;
-
-	if (!cfs_hash_with_shrink(hs))
-		return 0;
-
-	if ((hs->hs_cur_bits > hs->hs_min_bits) &&
-	    (__cfs_hash_theta(hs) < hs->hs_min_theta))
-		return hs->hs_cur_bits - 1;
-
-	return 0;
-}
-
-/**
- * don't allow inline rehash if:
- * - user wants non-blocking change (add/del) on hash table
- * - too many elements
- */
-static inline int
-cfs_hash_rehash_inline(struct cfs_hash *hs)
-{
-	return !cfs_hash_with_nblk_change(hs) &&
-	       atomic_read(&hs->hs_count) < CFS_HASH_LOOP_HOG;
-}
-
-/**
- * Add item @hnode to libcfs hash @hs using @key.  The registered
- * ops->hs_get function will be called when the item is added.
- */
-void
-cfs_hash_add(struct cfs_hash *hs, const void *key, struct hlist_node *hnode)
-{
-	struct cfs_hash_bd bd;
-	int bits;
-
-	LASSERT(hlist_unhashed(hnode));
-
-	cfs_hash_lock(hs, 0);
-	cfs_hash_bd_get_and_lock(hs, key, &bd, 1);
-
-	cfs_hash_key_validate(hs, key, hnode);
-	cfs_hash_bd_add_locked(hs, &bd, hnode);
-
-	cfs_hash_bd_unlock(hs, &bd, 1);
-
-	bits = cfs_hash_rehash_bits(hs);
-	cfs_hash_unlock(hs, 0);
-	if (bits > 0)
-		cfs_hash_rehash(hs, cfs_hash_rehash_inline(hs));
-}
-EXPORT_SYMBOL(cfs_hash_add);
-
-static struct hlist_node *
-cfs_hash_find_or_add(struct cfs_hash *hs, const void *key,
-		     struct hlist_node *hnode, int noref)
-{
-	struct hlist_node *ehnode;
-	struct cfs_hash_bd bds[2];
-	int bits = 0;
-
-	LASSERTF(hlist_unhashed(hnode), "hnode = %p\n", hnode);
-
-	cfs_hash_lock(hs, 0);
-	cfs_hash_dual_bd_get_and_lock(hs, key, bds, 1);
-
-	cfs_hash_key_validate(hs, key, hnode);
-	ehnode = cfs_hash_dual_bd_findadd_locked(hs, bds, key,
-						 hnode, noref);
-	cfs_hash_dual_bd_unlock(hs, bds, 1);
-
-	if (ehnode == hnode)	/* new item added */
-		bits = cfs_hash_rehash_bits(hs);
-	cfs_hash_unlock(hs, 0);
-	if (bits > 0)
-		cfs_hash_rehash(hs, cfs_hash_rehash_inline(hs));
-
-	return ehnode;
-}
-
-/**
- * Add item @hnode to libcfs hash @hs using @key.  The registered
- * ops->hs_get function will be called if the item was added.
- * Returns 0 on success or -EALREADY on key collisions.
- */
-int
-cfs_hash_add_unique(struct cfs_hash *hs, const void *key,
-		    struct hlist_node *hnode)
-{
-	return cfs_hash_find_or_add(hs, key, hnode, 1) != hnode ?
-	       -EALREADY : 0;
-}
-EXPORT_SYMBOL(cfs_hash_add_unique);
-
-/**
- * Add item @hnode to libcfs hash @hs using @key.  If this @key
- * already exists in the hash then ops->hs_get will be called on the
- * conflicting entry and that entry will be returned to the caller.
- * Otherwise ops->hs_get is called on the item which was added.
- */
-void *
-cfs_hash_findadd_unique(struct cfs_hash *hs, const void *key,
-			struct hlist_node *hnode)
-{
-	hnode = cfs_hash_find_or_add(hs, key, hnode, 0);
-
-	return cfs_hash_object(hs, hnode);
-}
-EXPORT_SYMBOL(cfs_hash_findadd_unique);
-
-/**
- * Delete item @hnode from the libcfs hash @hs using @key.  The @key
- * is required to ensure the correct hash bucket is locked since there
- * is no direct linkage from the item to the bucket.  The object
- * removed from the hash will be returned and obs->hs_put is called
- * on the removed object.
- */
-void *
-cfs_hash_del(struct cfs_hash *hs, const void *key, struct hlist_node *hnode)
-{
-	void *obj = NULL;
-	int bits = 0;
-	struct cfs_hash_bd bds[2];
-
-	cfs_hash_lock(hs, 0);
-	cfs_hash_dual_bd_get_and_lock(hs, key, bds, 1);
-
-	/* NB: do nothing if @hnode is not in hash table */
-	if (!hnode || !hlist_unhashed(hnode)) {
-		if (!bds[1].bd_bucket && hnode) {
-			cfs_hash_bd_del_locked(hs, &bds[0], hnode);
-		} else {
-			hnode = cfs_hash_dual_bd_finddel_locked(hs, bds,
-								key, hnode);
-		}
-	}
-
-	if (hnode) {
-		obj = cfs_hash_object(hs, hnode);
-		bits = cfs_hash_rehash_bits(hs);
-	}
-
-	cfs_hash_dual_bd_unlock(hs, bds, 1);
-	cfs_hash_unlock(hs, 0);
-	if (bits > 0)
-		cfs_hash_rehash(hs, cfs_hash_rehash_inline(hs));
-
-	return obj;
-}
-EXPORT_SYMBOL(cfs_hash_del);
-
-/**
- * Delete item given @key in libcfs hash @hs.  The first @key found in
- * the hash will be removed, if the key exists multiple times in the hash
- * @hs this function must be called once per key.  The removed object
- * will be returned and ops->hs_put is called on the removed object.
- */
-void *
-cfs_hash_del_key(struct cfs_hash *hs, const void *key)
-{
-	return cfs_hash_del(hs, key, NULL);
-}
-EXPORT_SYMBOL(cfs_hash_del_key);
-
-/**
- * Lookup an item using @key in the libcfs hash @hs and return it.
- * If the @key is found in the hash hs->hs_get() is called and the
- * matching objects is returned.  It is the callers responsibility
- * to call the counterpart ops->hs_put using the cfs_hash_put() macro
- * when when finished with the object.  If the @key was not found
- * in the hash @hs NULL is returned.
- */
-void *
-cfs_hash_lookup(struct cfs_hash *hs, const void *key)
-{
-	void *obj = NULL;
-	struct hlist_node *hnode;
-	struct cfs_hash_bd bds[2];
-
-	cfs_hash_lock(hs, 0);
-	cfs_hash_dual_bd_get_and_lock(hs, key, bds, 0);
-
-	hnode = cfs_hash_dual_bd_lookup_locked(hs, bds, key);
-	if (hnode)
-		obj = cfs_hash_object(hs, hnode);
-
-	cfs_hash_dual_bd_unlock(hs, bds, 0);
-	cfs_hash_unlock(hs, 0);
-
-	return obj;
-}
-EXPORT_SYMBOL(cfs_hash_lookup);
-
-static void
-cfs_hash_for_each_enter(struct cfs_hash *hs)
-{
-	LASSERT(!cfs_hash_is_exiting(hs));
-
-	if (!cfs_hash_with_rehash(hs))
-		return;
-	/*
-	 * NB: it's race on cfs_has_t::hs_iterating, but doesn't matter
-	 * because it's just an unreliable signal to rehash-thread,
-	 * rehash-thread will try to finish rehash ASAP when seeing this.
-	 */
-	hs->hs_iterating = 1;
-
-	cfs_hash_lock(hs, 1);
-	hs->hs_iterators++;
-	cfs_hash_unlock(hs, 1);
-
-	/* NB: iteration is mostly called by service thread,
-	 * we tend to cancel pending rehash-request, instead of
-	 * blocking service thread, we will relaunch rehash request
-	 * after iteration
-	 */
-	if (cfs_hash_is_rehashing(hs))
-		cfs_hash_rehash_cancel(hs);
-}
-
-static void
-cfs_hash_for_each_exit(struct cfs_hash *hs)
-{
-	int remained;
-	int bits;
-
-	if (!cfs_hash_with_rehash(hs))
-		return;
-	cfs_hash_lock(hs, 1);
-	remained = --hs->hs_iterators;
-	bits = cfs_hash_rehash_bits(hs);
-	cfs_hash_unlock(hs, 1);
-	/* NB: it's race on cfs_has_t::hs_iterating, see above */
-	if (!remained)
-		hs->hs_iterating = 0;
-	if (bits > 0) {
-		cfs_hash_rehash(hs, atomic_read(&hs->hs_count) <
-				    CFS_HASH_LOOP_HOG);
-	}
-}
-
-/**
- * For each item in the libcfs hash @hs call the passed callback @func
- * and pass to it as an argument each hash item and the private @data.
- *
- * a) the function may sleep!
- * b) during the callback:
- *    . the bucket lock is held so the callback must never sleep.
- *    . if @removal_safe is true, use can remove current item by
- *      cfs_hash_bd_del_locked
- */
-static u64
-cfs_hash_for_each_tight(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
-			void *data, int remove_safe)
-{
-	struct hlist_node *hnode;
-	struct hlist_node *pos;
-	struct cfs_hash_bd bd;
-	u64 count = 0;
-	int excl = !!remove_safe;
-	int loop = 0;
-	int i;
-
-	cfs_hash_for_each_enter(hs);
-
-	cfs_hash_lock(hs, 0);
-	LASSERT(!cfs_hash_is_rehashing(hs));
-
-	cfs_hash_for_each_bucket(hs, &bd, i) {
-		struct hlist_head *hhead;
-
-		cfs_hash_bd_lock(hs, &bd, excl);
-		if (!func) { /* only glimpse size */
-			count += bd.bd_bucket->hsb_count;
-			cfs_hash_bd_unlock(hs, &bd, excl);
-			continue;
-		}
-
-		cfs_hash_bd_for_each_hlist(hs, &bd, hhead) {
-			hlist_for_each_safe(hnode, pos, hhead) {
-				cfs_hash_bucket_validate(hs, &bd, hnode);
-				count++;
-				loop++;
-				if (func(hs, &bd, hnode, data)) {
-					cfs_hash_bd_unlock(hs, &bd, excl);
-					goto out;
-				}
-			}
-		}
-		cfs_hash_bd_unlock(hs, &bd, excl);
-		if (loop < CFS_HASH_LOOP_HOG)
-			continue;
-		loop = 0;
-		cfs_hash_unlock(hs, 0);
-		cond_resched();
-		cfs_hash_lock(hs, 0);
-	}
- out:
-	cfs_hash_unlock(hs, 0);
-
-	cfs_hash_for_each_exit(hs);
-	return count;
-}
-
-struct cfs_hash_cond_arg {
-	cfs_hash_cond_opt_cb_t	func;
-	void			*arg;
-};
-
-static int
-cfs_hash_cond_del_locked(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-			 struct hlist_node *hnode, void *data)
-{
-	struct cfs_hash_cond_arg *cond = data;
-
-	if (cond->func(cfs_hash_object(hs, hnode), cond->arg))
-		cfs_hash_bd_del_locked(hs, bd, hnode);
-	return 0;
-}
-
-/**
- * Delete item from the libcfs hash @hs when @func return true.
- * The write lock being hold during loop for each bucket to avoid
- * any object be reference.
- */
-void
-cfs_hash_cond_del(struct cfs_hash *hs, cfs_hash_cond_opt_cb_t func, void *data)
-{
-	struct cfs_hash_cond_arg arg = {
-		.func	= func,
-		.arg	= data,
-	};
-
-	cfs_hash_for_each_tight(hs, cfs_hash_cond_del_locked, &arg, 1);
-}
-EXPORT_SYMBOL(cfs_hash_cond_del);
-
-void
-cfs_hash_for_each(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
-		  void *data)
-{
-	cfs_hash_for_each_tight(hs, func, data, 0);
-}
-EXPORT_SYMBOL(cfs_hash_for_each);
-
-void
-cfs_hash_for_each_safe(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
-		       void *data)
-{
-	cfs_hash_for_each_tight(hs, func, data, 1);
-}
-EXPORT_SYMBOL(cfs_hash_for_each_safe);
-
-static int
-cfs_hash_peek(struct cfs_hash *hs, struct cfs_hash_bd *bd,
-	      struct hlist_node *hnode, void *data)
-{
-	*(int *)data = 0;
-	return 1; /* return 1 to break the loop */
-}
-
-int
-cfs_hash_is_empty(struct cfs_hash *hs)
-{
-	int empty = 1;
-
-	cfs_hash_for_each_tight(hs, cfs_hash_peek, &empty, 0);
-	return empty;
-}
-EXPORT_SYMBOL(cfs_hash_is_empty);
-
-u64
-cfs_hash_size_get(struct cfs_hash *hs)
-{
-	return cfs_hash_with_counter(hs) ?
-	       atomic_read(&hs->hs_count) :
-	       cfs_hash_for_each_tight(hs, NULL, NULL, 0);
-}
-EXPORT_SYMBOL(cfs_hash_size_get);
-
-/*
- * cfs_hash_for_each_relax:
- * Iterate the hash table and call @func on each item without
- * any lock. This function can't guarantee to finish iteration
- * if these features are enabled:
- *
- *  a. if rehash_key is enabled, an item can be moved from
- *     one bucket to another bucket
- *  b. user can remove non-zero-ref item from hash-table,
- *     so the item can be removed from hash-table, even worse,
- *     it's possible that user changed key and insert to another
- *     hash bucket.
- * there's no way for us to finish iteration correctly on previous
- * two cases, so iteration has to be stopped on change.
- */
-static int
-cfs_hash_for_each_relax(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
-			void *data, int start)
-{
-	struct hlist_node *next = NULL;
-	struct hlist_node *hnode;
-	struct cfs_hash_bd bd;
-	u32 version;
-	int count = 0;
-	int stop_on_change;
-	int has_put_locked;
-	int end = -1;
-	int rc = 0;
-	int i;
-
-	stop_on_change = cfs_hash_with_rehash_key(hs) ||
-			 !cfs_hash_with_no_itemref(hs);
-	has_put_locked = hs->hs_ops->hs_put_locked != NULL;
-	cfs_hash_lock(hs, 0);
-again:
-	LASSERT(!cfs_hash_is_rehashing(hs));
-
-	cfs_hash_for_each_bucket(hs, &bd, i) {
-		struct hlist_head *hhead;
-
-		if (i < start)
-			continue;
-		else if (end > 0 && i >= end)
-			break;
-
-		cfs_hash_bd_lock(hs, &bd, 0);
-		version = cfs_hash_bd_version_get(&bd);
-
-		cfs_hash_bd_for_each_hlist(hs, &bd, hhead) {
-			hnode = hhead->first;
-			if (!hnode)
-				continue;
-			cfs_hash_get(hs, hnode);
-
-			for (; hnode; hnode = next) {
-				cfs_hash_bucket_validate(hs, &bd, hnode);
-				next = hnode->next;
-				if (next)
-					cfs_hash_get(hs, next);
-				cfs_hash_bd_unlock(hs, &bd, 0);
-				cfs_hash_unlock(hs, 0);
-
-				rc = func(hs, &bd, hnode, data);
-				if (stop_on_change || !has_put_locked)
-					cfs_hash_put(hs, hnode);
-				cond_resched();
-				count++;
-
-				cfs_hash_lock(hs, 0);
-				cfs_hash_bd_lock(hs, &bd, 0);
-				if (stop_on_change) {
-					if (version !=
-					    cfs_hash_bd_version_get(&bd))
-						rc = -EINTR;
-				} else if (has_put_locked) {
-					cfs_hash_put_locked(hs, hnode);
-				}
-				if (rc) /* callback wants to break iteration */
-					break;
-			}
-			if (next) {
-				if (has_put_locked) {
-					cfs_hash_put_locked(hs, next);
-					next = NULL;
-				}
-				break;
-			} else if (rc) {
-				break;
-			}
-		}
-		cfs_hash_bd_unlock(hs, &bd, 0);
-		if (next && !has_put_locked) {
-			cfs_hash_put(hs, next);
-			next = NULL;
-		}
-		if (rc) /* callback wants to break iteration */
-			break;
-	}
-	if (start > 0 && !rc) {
-		end = start;
-		start = 0;
-		goto again;
-	}
-
-	cfs_hash_unlock(hs, 0);
-	return count;
-}
-
-int
-cfs_hash_for_each_nolock(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
-			 void *data, int start)
-{
-	if (cfs_hash_with_no_lock(hs) ||
-	    cfs_hash_with_rehash_key(hs) ||
-	    !cfs_hash_with_no_itemref(hs))
-		return -EOPNOTSUPP;
-
-	if (!hs->hs_ops->hs_get ||
-	    (!hs->hs_ops->hs_put && !hs->hs_ops->hs_put_locked))
-		return -EOPNOTSUPP;
-
-	cfs_hash_for_each_enter(hs);
-	cfs_hash_for_each_relax(hs, func, data, start);
-	cfs_hash_for_each_exit(hs);
-
-	return 0;
-}
-EXPORT_SYMBOL(cfs_hash_for_each_nolock);
-
-/**
- * For each hash bucket in the libcfs hash @hs call the passed callback
- * @func until all the hash buckets are empty.  The passed callback @func
- * or the previously registered callback hs->hs_put must remove the item
- * from the hash.  You may either use the cfs_hash_del() or hlist_del()
- * functions.  No rwlocks will be held during the callback @func it is
- * safe to sleep if needed.  This function will not terminate until the
- * hash is empty.  Note it is still possible to concurrently add new
- * items in to the hash.  It is the callers responsibility to ensure
- * the required locking is in place to prevent concurrent insertions.
- */
-int
-cfs_hash_for_each_empty(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
-			void *data)
-{
-	unsigned int i = 0;
-
-	if (cfs_hash_with_no_lock(hs))
-		return -EOPNOTSUPP;
-
-	if (!hs->hs_ops->hs_get ||
-	    (!hs->hs_ops->hs_put && !hs->hs_ops->hs_put_locked))
-		return -EOPNOTSUPP;
-
-	cfs_hash_for_each_enter(hs);
-	while (cfs_hash_for_each_relax(hs, func, data, 0)) {
-		CDEBUG(D_INFO, "Try to empty hash: %s, loop: %u\n",
-		       hs->hs_name, i++);
-	}
-	cfs_hash_for_each_exit(hs);
-	return 0;
-}
-EXPORT_SYMBOL(cfs_hash_for_each_empty);
-
-void
-cfs_hash_hlist_for_each(struct cfs_hash *hs, unsigned int hindex,
-			cfs_hash_for_each_cb_t func, void *data)
-{
-	struct hlist_head *hhead;
-	struct hlist_node *hnode;
-	struct cfs_hash_bd bd;
-
-	cfs_hash_for_each_enter(hs);
-	cfs_hash_lock(hs, 0);
-	if (hindex >= CFS_HASH_NHLIST(hs))
-		goto out;
-
-	cfs_hash_bd_index_set(hs, hindex, &bd);
-
-	cfs_hash_bd_lock(hs, &bd, 0);
-	hhead = cfs_hash_bd_hhead(hs, &bd);
-	hlist_for_each(hnode, hhead) {
-		if (func(hs, &bd, hnode, data))
-			break;
-	}
-	cfs_hash_bd_unlock(hs, &bd, 0);
-out:
-	cfs_hash_unlock(hs, 0);
-	cfs_hash_for_each_exit(hs);
-}
-EXPORT_SYMBOL(cfs_hash_hlist_for_each);
-
-/*
- * For each item in the libcfs hash @hs which matches the @key call
- * the passed callback @func and pass to it as an argument each hash
- * item and the private @data. During the callback the bucket lock
- * is held so the callback must never sleep.
- */
-void
-cfs_hash_for_each_key(struct cfs_hash *hs, const void *key,
-		      cfs_hash_for_each_cb_t func, void *data)
-{
-	struct hlist_node *hnode;
-	struct cfs_hash_bd bds[2];
-	unsigned int i;
-
-	cfs_hash_lock(hs, 0);
-
-	cfs_hash_dual_bd_get_and_lock(hs, key, bds, 0);
-
-	cfs_hash_for_each_bd(bds, 2, i) {
-		struct hlist_head *hlist = cfs_hash_bd_hhead(hs, &bds[i]);
-
-		hlist_for_each(hnode, hlist) {
-			cfs_hash_bucket_validate(hs, &bds[i], hnode);
-
-			if (cfs_hash_keycmp(hs, key, hnode)) {
-				if (func(hs, &bds[i], hnode, data))
-					break;
-			}
-		}
-	}
-
-	cfs_hash_dual_bd_unlock(hs, bds, 0);
-	cfs_hash_unlock(hs, 0);
-}
-EXPORT_SYMBOL(cfs_hash_for_each_key);
-
-/**
- * Rehash the libcfs hash @hs to the given @bits.  This can be used
- * to grow the hash size when excessive chaining is detected, or to
- * shrink the hash when it is larger than needed.  When the CFS_HASH_REHASH
- * flag is set in @hs the libcfs hash may be dynamically rehashed
- * during addition or removal if the hash's theta value exceeds
- * either the hs->hs_min_theta or hs->max_theta values.  By default
- * these values are tuned to keep the chained hash depth small, and
- * this approach assumes a reasonably uniform hashing function.  The
- * theta thresholds for @hs are tunable via cfs_hash_set_theta().
- */
-void
-cfs_hash_rehash_cancel(struct cfs_hash *hs)
-{
-	LASSERT(cfs_hash_with_rehash(hs));
-	cancel_work_sync(&hs->hs_rehash_work);
-}
-
-void
-cfs_hash_rehash(struct cfs_hash *hs, int do_rehash)
-{
-	int rc;
-
-	LASSERT(cfs_hash_with_rehash(hs) && !cfs_hash_with_no_lock(hs));
-
-	cfs_hash_lock(hs, 1);
-
-	rc = cfs_hash_rehash_bits(hs);
-	if (rc <= 0) {
-		cfs_hash_unlock(hs, 1);
-		return;
-	}
-
-	hs->hs_rehash_bits = rc;
-	if (!do_rehash) {
-		/* launch and return */
-		queue_work(cfs_rehash_wq, &hs->hs_rehash_work);
-		cfs_hash_unlock(hs, 1);
-		return;
-	}
-
-	/* rehash right now */
-	cfs_hash_unlock(hs, 1);
-
-	cfs_hash_rehash_worker(&hs->hs_rehash_work);
-}
-
-static int
-cfs_hash_rehash_bd(struct cfs_hash *hs, struct cfs_hash_bd *old)
-{
-	struct cfs_hash_bd new;
-	struct hlist_head *hhead;
-	struct hlist_node *hnode;
-	struct hlist_node *pos;
-	void *key;
-	int c = 0;
-
-	/* hold cfs_hash_lock(hs, 1), so don't need any bucket lock */
-	cfs_hash_bd_for_each_hlist(hs, old, hhead) {
-		hlist_for_each_safe(hnode, pos, hhead) {
-			key = cfs_hash_key(hs, hnode);
-			LASSERT(key);
-			/* Validate hnode is in the correct bucket. */
-			cfs_hash_bucket_validate(hs, old, hnode);
-			/*
-			 * Delete from old hash bucket; move to new bucket.
-			 * ops->hs_key must be defined.
-			 */
-			cfs_hash_bd_from_key(hs, hs->hs_rehash_buckets,
-					     hs->hs_rehash_bits, key, &new);
-			cfs_hash_bd_move_locked(hs, old, &new, hnode);
-			c++;
-		}
-	}
-
-	return c;
-}
-
-static void
-cfs_hash_rehash_worker(struct work_struct *work)
-{
-	struct cfs_hash *hs = container_of(work, struct cfs_hash, hs_rehash_work);
-	struct cfs_hash_bucket **bkts;
-	struct cfs_hash_bd bd;
-	unsigned int old_size;
-	unsigned int new_size;
-	int bsize;
-	int count = 0;
-	int rc = 0;
-	int i;
-
-	LASSERT(hs && cfs_hash_with_rehash(hs));
-
-	cfs_hash_lock(hs, 0);
-	LASSERT(cfs_hash_is_rehashing(hs));
-
-	old_size = CFS_HASH_NBKT(hs);
-	new_size = CFS_HASH_RH_NBKT(hs);
-
-	cfs_hash_unlock(hs, 0);
-
-	/*
-	 * don't need hs::hs_rwlock for hs::hs_buckets,
-	 * because nobody can change bkt-table except me.
-	 */
-	bkts = cfs_hash_buckets_realloc(hs, hs->hs_buckets,
-					old_size, new_size);
-	cfs_hash_lock(hs, 1);
-	if (!bkts) {
-		rc = -ENOMEM;
-		goto out;
-	}
-
-	if (bkts == hs->hs_buckets) {
-		bkts = NULL; /* do nothing */
-		goto out;
-	}
-
-	rc = __cfs_hash_theta(hs);
-	if ((rc >= hs->hs_min_theta) && (rc <= hs->hs_max_theta)) {
-		/* free the new allocated bkt-table */
-		old_size = new_size;
-		new_size = CFS_HASH_NBKT(hs);
-		rc = -EALREADY;
-		goto out;
-	}
-
-	LASSERT(!hs->hs_rehash_buckets);
-	hs->hs_rehash_buckets = bkts;
-
-	rc = 0;
-	cfs_hash_for_each_bucket(hs, &bd, i) {
-		if (cfs_hash_is_exiting(hs)) {
-			rc = -ESRCH;
-			/* someone wants to destroy the hash, abort now */
-			if (old_size < new_size) /* OK to free old bkt-table */
-				break;
-			/* it's shrinking, need free new bkt-table */
-			hs->hs_rehash_buckets = NULL;
-			old_size = new_size;
-			new_size = CFS_HASH_NBKT(hs);
-			goto out;
-		}
-
-		count += cfs_hash_rehash_bd(hs, &bd);
-		if (count < CFS_HASH_LOOP_HOG ||
-		    cfs_hash_is_iterating(hs)) { /* need to finish ASAP */
-			continue;
-		}
-
-		count = 0;
-		cfs_hash_unlock(hs, 1);
-		cond_resched();
-		cfs_hash_lock(hs, 1);
-	}
-
-	hs->hs_rehash_count++;
-
-	bkts = hs->hs_buckets;
-	hs->hs_buckets = hs->hs_rehash_buckets;
-	hs->hs_rehash_buckets = NULL;
-
-	hs->hs_cur_bits = hs->hs_rehash_bits;
-out:
-	hs->hs_rehash_bits = 0;
-	bsize = cfs_hash_bkt_size(hs);
-	cfs_hash_unlock(hs, 1);
-	/* can't refer to @hs anymore because it could be destroyed */
-	if (bkts)
-		cfs_hash_buckets_free(bkts, bsize, new_size, old_size);
-	if (rc)
-		CDEBUG(D_INFO, "early quit of rehashing: %d\n", rc);
-}
-
-/**
- * Rehash the object referenced by @hnode in the libcfs hash @hs.  The
- * @old_key must be provided to locate the objects previous location
- * in the hash, and the @new_key will be used to reinsert the object.
- * Use this function instead of a cfs_hash_add() + cfs_hash_del()
- * combo when it is critical that there is no window in time where the
- * object is missing from the hash.  When an object is being rehashed
- * the registered cfs_hash_get() and cfs_hash_put() functions will
- * not be called.
- */
-void cfs_hash_rehash_key(struct cfs_hash *hs, const void *old_key,
-			 void *new_key, struct hlist_node *hnode)
-{
-	struct cfs_hash_bd bds[3];
-	struct cfs_hash_bd old_bds[2];
-	struct cfs_hash_bd new_bd;
-
-	LASSERT(!hlist_unhashed(hnode));
-
-	cfs_hash_lock(hs, 0);
-
-	cfs_hash_dual_bd_get(hs, old_key, old_bds);
-	cfs_hash_bd_get(hs, new_key, &new_bd);
-
-	bds[0] = old_bds[0];
-	bds[1] = old_bds[1];
-	bds[2] = new_bd;
-
-	/* NB: bds[0] and bds[1] are ordered already */
-	cfs_hash_bd_order(&bds[1], &bds[2]);
-	cfs_hash_bd_order(&bds[0], &bds[1]);
-
-	cfs_hash_multi_bd_lock(hs, bds, 3, 1);
-	if (likely(!old_bds[1].bd_bucket)) {
-		cfs_hash_bd_move_locked(hs, &old_bds[0], &new_bd, hnode);
-	} else {
-		cfs_hash_dual_bd_finddel_locked(hs, old_bds, old_key, hnode);
-		cfs_hash_bd_add_locked(hs, &new_bd, hnode);
-	}
-	/* overwrite key inside locks, otherwise may screw up with
-	 * other operations, i.e: rehash
-	 */
-	cfs_hash_keycpy(hs, hnode, new_key);
-
-	cfs_hash_multi_bd_unlock(hs, bds, 3, 1);
-	cfs_hash_unlock(hs, 0);
-}
-EXPORT_SYMBOL(cfs_hash_rehash_key);
-
-void cfs_hash_debug_header(struct seq_file *m)
-{
-	seq_printf(m, "%-*s   cur   min   max theta t-min t-max flags rehash   count  maxdep maxdepb distribution\n",
-		   CFS_HASH_BIGNAME_LEN, "name");
-}
-EXPORT_SYMBOL(cfs_hash_debug_header);
-
-static struct cfs_hash_bucket **
-cfs_hash_full_bkts(struct cfs_hash *hs)
-{
-	/* NB: caller should hold hs->hs_rwlock if REHASH is set */
-	if (!hs->hs_rehash_buckets)
-		return hs->hs_buckets;
-
-	LASSERT(hs->hs_rehash_bits);
-	return hs->hs_rehash_bits > hs->hs_cur_bits ?
-	       hs->hs_rehash_buckets : hs->hs_buckets;
-}
-
-static unsigned int
-cfs_hash_full_nbkt(struct cfs_hash *hs)
-{
-	/* NB: caller should hold hs->hs_rwlock if REHASH is set */
-	if (!hs->hs_rehash_buckets)
-		return CFS_HASH_NBKT(hs);
-
-	LASSERT(hs->hs_rehash_bits);
-	return hs->hs_rehash_bits > hs->hs_cur_bits ?
-	       CFS_HASH_RH_NBKT(hs) : CFS_HASH_NBKT(hs);
-}
-
-void cfs_hash_debug_str(struct cfs_hash *hs, struct seq_file *m)
-{
-	int dist[8] = { 0, };
-	int maxdep = -1;
-	int maxdepb = -1;
-	int total = 0;
-	int theta;
-	int i;
-
-	cfs_hash_lock(hs, 0);
-	theta = __cfs_hash_theta(hs);
-
-	seq_printf(m, "%-*s %5d %5d %5d %d.%03d %d.%03d %d.%03d  0x%02x %6d ",
-		   CFS_HASH_BIGNAME_LEN, hs->hs_name,
-		   1 << hs->hs_cur_bits, 1 << hs->hs_min_bits,
-		   1 << hs->hs_max_bits,
-		   __cfs_hash_theta_int(theta), __cfs_hash_theta_frac(theta),
-		   __cfs_hash_theta_int(hs->hs_min_theta),
-		   __cfs_hash_theta_frac(hs->hs_min_theta),
-		   __cfs_hash_theta_int(hs->hs_max_theta),
-		   __cfs_hash_theta_frac(hs->hs_max_theta),
-		   hs->hs_flags, hs->hs_rehash_count);
-
-	/*
-	 * The distribution is a summary of the chained hash depth in
-	 * each of the libcfs hash buckets.  Each buckets hsb_count is
-	 * divided by the hash theta value and used to generate a
-	 * histogram of the hash distribution.  A uniform hash will
-	 * result in all hash buckets being close to the average thus
-	 * only the first few entries in the histogram will be non-zero.
-	 * If you hash function results in a non-uniform hash the will
-	 * be observable by outlier bucks in the distribution histogram.
-	 *
-	 * Uniform hash distribution:		128/128/0/0/0/0/0/0
-	 * Non-Uniform hash distribution:	128/125/0/0/0/0/2/1
-	 */
-	for (i = 0; i < cfs_hash_full_nbkt(hs); i++) {
-		struct cfs_hash_bd bd;
-
-		bd.bd_bucket = cfs_hash_full_bkts(hs)[i];
-		cfs_hash_bd_lock(hs, &bd, 0);
-		if (maxdep < bd.bd_bucket->hsb_depmax) {
-			maxdep  = bd.bd_bucket->hsb_depmax;
-			maxdepb = ffz(~maxdep);
-		}
-		total += bd.bd_bucket->hsb_count;
-		dist[min(fls(bd.bd_bucket->hsb_count / max(theta, 1)), 7)]++;
-		cfs_hash_bd_unlock(hs, &bd, 0);
-	}
-
-	seq_printf(m, "%7d %7d %7d ", total, maxdep, maxdepb);
-	for (i = 0; i < 8; i++)
-		seq_printf(m, "%d%c",  dist[i], (i == 7) ? '\n' : '/');
-
-	cfs_hash_unlock(hs, 0);
-}
-EXPORT_SYMBOL(cfs_hash_debug_str);