[deliverable/linux.git] / net / netfilter / nft_set_hash.c

/*
 * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/jhash.h>
#include <linux/netlink.h>
#include <linux/workqueue.h>
#include <linux/rhashtable.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>

/* We target a hash table size of 4, element hint is 75% of final size */
#define NFT_HASH_ELEMENT_HINT 3

struct nft_hash {
	struct rhashtable		ht;
	struct delayed_work		gc_work;
};

struct nft_hash_elem {
	struct rhash_head		node;
	struct nft_set_ext		ext;
};

struct nft_hash_cmp_arg {
	const struct nft_set		*set;
	const u32			*key;
	u8				genmask;
};

static const struct rhashtable_params nft_hash_params;

static inline u32 nft_hash_key(const void *data, u32 len, u32 seed)
{
	const struct nft_hash_cmp_arg *arg = data;

	return jhash(arg->key, len, seed);
}

static inline u32 nft_hash_obj(const void *data, u32 len, u32 seed)
{
	const struct nft_hash_elem *he = data;

	return jhash(nft_set_ext_key(&he->ext), len, seed);
}

static inline int nft_hash_cmp(struct rhashtable_compare_arg *arg,
			       const void *ptr)
{
	const struct nft_hash_cmp_arg *x = arg->key;
	const struct nft_hash_elem *he = ptr;

	if (memcmp(nft_set_ext_key(&he->ext), x->key, x->set->klen))
		return 1;
	if (nft_set_elem_expired(&he->ext))
		return 1;
	if (!nft_set_elem_active(&he->ext, x->genmask))
		return 1;
	return 0;
}

static bool nft_hash_lookup(const struct net *net, const struct nft_set *set,
			    const u32 *key, const struct nft_set_ext **ext)
{
	struct nft_hash *priv = nft_set_priv(set);
	const struct nft_hash_elem *he;
	struct nft_hash_cmp_arg arg = {
		.genmask = nft_genmask_cur(net),
		.set	 = set,
		.key	 = key,
	};

	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
	if (he != NULL)
		*ext = &he->ext;

	return !!he;
}

static bool nft_hash_update(struct nft_set *set, const u32 *key,
			    void *(*new)(struct nft_set *,
					 const struct nft_expr *,
					 struct nft_regs *regs),
			    const struct nft_expr *expr,
			    struct nft_regs *regs,
			    const struct nft_set_ext **ext)
{
	struct nft_hash *priv = nft_set_priv(set);
	struct nft_hash_elem *he;
	struct nft_hash_cmp_arg arg = {
		.genmask = NFT_GENMASK_ANY,
		.set	 = set,
		.key	 = key,
	};

	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
	if (he != NULL)
		goto out;

	he = new(set, expr, regs);
	if (he == NULL)
		goto err1;
	if (rhashtable_lookup_insert_key(&priv->ht, &arg, &he->node,
					 nft_hash_params))
		goto err2;
out:
	*ext = &he->ext;
	return true;

err2:
	nft_set_elem_destroy(set, he);
err1:
	return false;
}

static int nft_hash_insert(const struct net *net, const struct nft_set *set,
			   const struct nft_set_elem *elem,
			   struct nft_set_ext **ext)
{
	struct nft_hash *priv = nft_set_priv(set);
	struct nft_hash_elem *he = elem->priv;
	struct nft_hash_cmp_arg arg = {
		.genmask = nft_genmask_next(net),
		.set	 = set,
		.key	 = elem->key.val.data,
	};
	struct nft_hash_elem *prev;

	prev = rhashtable_lookup_get_insert_key(&priv->ht, &arg, &he->node,
					       nft_hash_params);
	if (IS_ERR(prev))
		return PTR_ERR(prev);
	if (prev) {
		*ext = &prev->ext;
		return -EEXIST;
	}
	return 0;
}

static void nft_hash_activate(const struct net *net, const struct nft_set *set,
			      const struct nft_set_elem *elem)
{
	struct nft_hash_elem *he = elem->priv;

	nft_set_elem_change_active(net, set, &he->ext);
	nft_set_elem_clear_busy(&he->ext);
}

static void *nft_hash_deactivate(const struct net *net,
				 const struct nft_set *set,
				 const struct nft_set_elem *elem)
{
	struct nft_hash *priv = nft_set_priv(set);
	struct nft_hash_elem *he;
	struct nft_hash_cmp_arg arg = {
		.genmask = nft_genmask_next(net),
		.set	 = set,
		.key	 = elem->key.val.data,
	};

	rcu_read_lock();
	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
	if (he != NULL) {
		if (!nft_set_elem_mark_busy(&he->ext) ||
		    !nft_is_active(net, &he->ext))
			nft_set_elem_change_active(net, set, &he->ext);
		else
			he = NULL;
	}
	rcu_read_unlock();

	return he;
}

static void nft_hash_remove(const struct nft_set *set,
			    const struct nft_set_elem *elem)
{
	struct nft_hash *priv = nft_set_priv(set);
	struct nft_hash_elem *he = elem->priv;

	rhashtable_remove_fast(&priv->ht, &he->node, nft_hash_params);
}

static void nft_hash_walk(const struct nft_ctx *ctx, const struct nft_set *set,
			  struct nft_set_iter *iter)
{
	struct nft_hash *priv = nft_set_priv(set);
	struct nft_hash_elem *he;
	struct rhashtable_iter hti;
	struct nft_set_elem elem;
	int err;

	err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
	iter->err = err;
	if (err)
		return;

	err = rhashtable_walk_start(&hti);
	if (err && err != -EAGAIN) {
		iter->err = err;
		goto out;
	}

	while ((he = rhashtable_walk_next(&hti))) {
		if (IS_ERR(he)) {
			err = PTR_ERR(he);
			if (err != -EAGAIN) {
				iter->err = err;
				goto out;
			}

			continue;
		}

		if (iter->count < iter->skip)
			goto cont;
		if (nft_set_elem_expired(&he->ext))
			goto cont;
		if (!nft_set_elem_active(&he->ext, iter->genmask))
			goto cont;

		elem.priv = he;

		iter->err = iter->fn(ctx, set, iter, &elem);
		if (iter->err < 0)
			goto out;

cont:
		iter->count++;
	}

out:
	rhashtable_walk_stop(&hti);
	rhashtable_walk_exit(&hti);
}

static void nft_hash_gc(struct work_struct *work)
{
	struct nft_set *set;
	struct nft_hash_elem *he;
	struct nft_hash *priv;
	struct nft_set_gc_batch *gcb = NULL;
	struct rhashtable_iter hti;
	int err;

	priv = container_of(work, struct nft_hash, gc_work.work);
	set  = nft_set_container_of(priv);

	err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
	if (err)
		goto schedule;

	err = rhashtable_walk_start(&hti);
	if (err && err != -EAGAIN)
		goto out;

	while ((he = rhashtable_walk_next(&hti))) {
		if (IS_ERR(he)) {
			if (PTR_ERR(he) != -EAGAIN)
				goto out;
			continue;
		}

		if (!nft_set_elem_expired(&he->ext))
			continue;
		if (nft_set_elem_mark_busy(&he->ext))
			continue;

		gcb = nft_set_gc_batch_check(set, gcb, GFP_ATOMIC);
		if (gcb == NULL)
			goto out;
		rhashtable_remove_fast(&priv->ht, &he->node, nft_hash_params);
		atomic_dec(&set->nelems);
		nft_set_gc_batch_add(gcb, he);
	}
out:
	rhashtable_walk_stop(&hti);
	rhashtable_walk_exit(&hti);

	nft_set_gc_batch_complete(gcb);
schedule:
	queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
			   nft_set_gc_interval(set));
}

static unsigned int nft_hash_privsize(const struct nlattr * const nla[])
{
	return sizeof(struct nft_hash);
}

static const struct rhashtable_params nft_hash_params = {
	.head_offset		= offsetof(struct nft_hash_elem, node),
	.hashfn			= nft_hash_key,
	.obj_hashfn		= nft_hash_obj,
	.obj_cmpfn		= nft_hash_cmp,
	.automatic_shrinking	= true,
};

static int nft_hash_init(const struct nft_set *set,
			 const struct nft_set_desc *desc,
			 const struct nlattr * const tb[])
{
	struct nft_hash *priv = nft_set_priv(set);
	struct rhashtable_params params = nft_hash_params;
	int err;

	params.nelem_hint = desc->size ?: NFT_HASH_ELEMENT_HINT;
	params.key_len	  = set->klen;

	err = rhashtable_init(&priv->ht, &params);
	if (err < 0)
		return err;

	INIT_DEFERRABLE_WORK(&priv->gc_work, nft_hash_gc);
	if (set->flags & NFT_SET_TIMEOUT)
		queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
				   nft_set_gc_interval(set));
	return 0;
}

static void nft_hash_elem_destroy(void *ptr, void *arg)
{
	nft_set_elem_destroy((const struct nft_set *)arg, ptr);
}

static void nft_hash_destroy(const struct nft_set *set)
{
	struct nft_hash *priv = nft_set_priv(set);

	cancel_delayed_work_sync(&priv->gc_work);
	rhashtable_free_and_destroy(&priv->ht, nft_hash_elem_destroy,
				    (void *)set);
}

static bool nft_hash_estimate(const struct nft_set_desc *desc, u32 features,
			      struct nft_set_estimate *est)
{
	unsigned int esize;

	esize = sizeof(struct nft_hash_elem);
	if (desc->size) {
		est->size = sizeof(struct nft_hash) +
			    roundup_pow_of_two(desc->size * 4 / 3) *
			    sizeof(struct nft_hash_elem *) +
			    desc->size * esize;
	} else {
		/* Resizing happens when the load drops below 30% or goes
		 * above 75%. The average of 52.5% load (approximated by 50%)
		 * is used for the size estimation of the hash buckets,
		 * meaning we calculate two buckets per element.
		 */
		est->size = esize + 2 * sizeof(struct nft_hash_elem *);
	}

	est->class = NFT_SET_CLASS_O_1;

	return true;
}

static struct nft_set_ops nft_hash_ops __read_mostly = {
	.privsize       = nft_hash_privsize,
	.elemsize	= offsetof(struct nft_hash_elem, ext),
	.estimate	= nft_hash_estimate,
	.init		= nft_hash_init,
	.destroy	= nft_hash_destroy,
	.insert		= nft_hash_insert,
	.activate	= nft_hash_activate,
	.deactivate	= nft_hash_deactivate,
	.remove		= nft_hash_remove,
	.lookup		= nft_hash_lookup,
	.update		= nft_hash_update,
	.walk		= nft_hash_walk,
	.features	= NFT_SET_MAP | NFT_SET_TIMEOUT,
	.owner		= THIS_MODULE,
};

static int __init nft_hash_module_init(void)
{
	return nft_register_set(&nft_hash_ops);
}

static void __exit nft_hash_module_exit(void)
{
	nft_unregister_set(&nft_hash_ops);
}

module_init(nft_hash_module_init);
module_exit(nft_hash_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_SET();
Commit	Line	Data
96518518	1	/*
ce6eb0d7	2	* Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>
96518518 PM	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*
	8	* Development of this code funded by Astaro AG (http://www.astaro.com/)
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/init.h>
	13	#include <linux/module.h>
	14	#include <linux/list.h>
c50b960c	15	#include <linux/log2.h>
96518518 PM	16	#include <linux/jhash.h>
96518518 PM	17	#include <linux/netlink.h>
9d098292	18	#include <linux/workqueue.h>
cfe4a9dd	19	#include <linux/rhashtable.h>
96518518 PM	20	#include <linux/netfilter.h>
	21	#include <linux/netfilter/nf_tables.h>
	22	#include <net/netfilter/nf_tables.h>
	23
cfe4a9dd TG	24	/* We target a hash table size of 4, element hint is 75% of final size */
cfe4a9dd TG	25	#define NFT_HASH_ELEMENT_HINT 3
96518518	26
745f5450 PM	27	struct nft_hash {
745f5450 PM	28	struct rhashtable ht;
9d098292	29	struct delayed_work gc_work;
745f5450 PM	30	};
745f5450 PM	31
96518518	32	struct nft_hash_elem {
cfe4a9dd	33	struct rhash_head node;
fe2811eb	34	struct nft_set_ext ext;
96518518 PM	35	};
96518518 PM	36
bfd6e327 PM	37	struct nft_hash_cmp_arg {
bfd6e327 PM	38	const struct nft_set *set;
8cd8937a	39	const u32 *key;
cc02e457	40	u8 genmask;
bfd6e327 PM	41	};
bfd6e327 PM	42
fa377321 HX	43	static const struct rhashtable_params nft_hash_params;
fa377321 HX	44
bfd6e327 PM	45	static inline u32 nft_hash_key(const void *data, u32 len, u32 seed)
	46	{
	47	const struct nft_hash_cmp_arg *arg = data;
	48
	49	return jhash(arg->key, len, seed);
	50	}
	51
	52	static inline u32 nft_hash_obj(const void *data, u32 len, u32 seed)
	53	{
	54	const struct nft_hash_elem *he = data;
	55
fe2811eb	56	return jhash(nft_set_ext_key(&he->ext), len, seed);
bfd6e327 PM	57	}
	58
	59	static inline int nft_hash_cmp(struct rhashtable_compare_arg *arg,
	60	const void *ptr)
	61	{
	62	const struct nft_hash_cmp_arg *x = arg->key;
	63	const struct nft_hash_elem *he = ptr;
	64
e562d860	65	if (memcmp(nft_set_ext_key(&he->ext), x->key, x->set->klen))
bfd6e327	66	return 1;
9d098292 PM	67	if (nft_set_elem_expired(&he->ext))
9d098292 PM	68	return 1;
cc02e457 PM	69	if (!nft_set_elem_active(&he->ext, x->genmask))
cc02e457 PM	70	return 1;
bfd6e327 PM	71	return 0;
	72	}
	73
42a55769 PNA	74	static bool nft_hash_lookup(const struct net net, const struct nft_set set,
42a55769 PNA	75	const u32 key, const struct nft_set_ext *ext)
96518518	76	{
745f5450	77	struct nft_hash *priv = nft_set_priv(set);
20a69341	78	const struct nft_hash_elem *he;
bfd6e327	79	struct nft_hash_cmp_arg arg = {
42a55769	80	.genmask = nft_genmask_cur(net),
bfd6e327 PM	81	.set = set,
	82	.key = key,
	83	};
ce6eb0d7	84
bfd6e327	85	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
b2832dd6 PM	86	if (he != NULL)
b2832dd6 PM	87	*ext = &he->ext;
ce6eb0d7	88
cfe4a9dd	89	return !!he;
96518518 PM	90	}
96518518 PM	91
8cd8937a	92	static bool nft_hash_update(struct nft_set set, const u32 key,
22fe54d5 PM	93	void (new)(struct nft_set *,
22fe54d5 PM	94	const struct nft_expr *,
a55e22e9	95	struct nft_regs *regs),
22fe54d5	96	const struct nft_expr *expr,
a55e22e9	97	struct nft_regs *regs,
22fe54d5 PM	98	const struct nft_set_ext **ext)
	99	{
	100	struct nft_hash *priv = nft_set_priv(set);
	101	struct nft_hash_elem *he;
	102	struct nft_hash_cmp_arg arg = {
	103	.genmask = NFT_GENMASK_ANY,
	104	.set = set,
	105	.key = key,
	106	};
	107
	108	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
	109	if (he != NULL)
	110	goto out;
	111
a55e22e9	112	he = new(set, expr, regs);
22fe54d5 PM	113	if (he == NULL)
	114	goto err1;
	115	if (rhashtable_lookup_insert_key(&priv->ht, &arg, &he->node,
	116	nft_hash_params))
	117	goto err2;
	118	out:
	119	*ext = &he->ext;
	120	return true;
	121
	122	err2:
	123	nft_set_elem_destroy(set, he);
	124	err1:
	125	return false;
	126	}
	127
42a55769	128	static int nft_hash_insert(const struct net net, const struct nft_set set,
c016c7e4 PNA	129	const struct nft_set_elem *elem,
c016c7e4 PNA	130	struct nft_set_ext **ext)
96518518	131	{
745f5450	132	struct nft_hash *priv = nft_set_priv(set);
fe2811eb	133	struct nft_hash_elem *he = elem->priv;
bfd6e327	134	struct nft_hash_cmp_arg arg = {
42a55769	135	.genmask = nft_genmask_next(net),
bfd6e327	136	.set = set,
7d740264	137	.key = elem->key.val.data,
bfd6e327	138	};
c016c7e4 PNA	139	struct nft_hash_elem *prev;
	140
	141	prev = rhashtable_lookup_get_insert_key(&priv->ht, &arg, &he->node,
	142	nft_hash_params);
	143	if (IS_ERR(prev))
	144	return PTR_ERR(prev);
	145	if (prev) {
	146	*ext = &prev->ext;
	147	return -EEXIST;
	148	}
	149	return 0;
96518518 PM	150	}
96518518 PM	151
42a55769	152	static void nft_hash_activate(const struct net net, const struct nft_set set,
cc02e457	153	const struct nft_set_elem *elem)
96518518	154	{
cc02e457	155	struct nft_hash_elem *he = elem->priv;
ce6eb0d7	156
42a55769	157	nft_set_elem_change_active(net, set, &he->ext);
9d098292	158	nft_set_elem_clear_busy(&he->ext);
20a69341	159	}
96518518	160
42a55769 PNA	161	static void nft_hash_deactivate(const struct net net,
42a55769 PNA	162	const struct nft_set *set,
cc02e457	163	const struct nft_set_elem *elem)
20a69341	164	{
745f5450	165	struct nft_hash *priv = nft_set_priv(set);
fa377321	166	struct nft_hash_elem *he;
bfd6e327	167	struct nft_hash_cmp_arg arg = {
8eee54be	168	.genmask = nft_genmask_next(net),
bfd6e327	169	.set = set,
7d740264	170	.key = elem->key.val.data,
bfd6e327	171	};
fa377321	172
9d098292	173	rcu_read_lock();
bfd6e327	174	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
9d098292	175	if (he != NULL) {
8eee54be PNA	176	if (!nft_set_elem_mark_busy(&he->ext) \|\|
8eee54be PNA	177	!nft_is_active(net, &he->ext))
42a55769	178	nft_set_elem_change_active(net, set, &he->ext);
9d098292 PM	179	else
	180	he = NULL;
	181	}
	182	rcu_read_unlock();
8d24c0b4	183
cc02e457 PM	184	return he;
cc02e457 PM	185	}
8d24c0b4	186
cc02e457 PM	187	static void nft_hash_remove(const struct nft_set *set,
	188	const struct nft_set_elem *elem)
	189	{
	190	struct nft_hash *priv = nft_set_priv(set);
	191	struct nft_hash_elem *he = elem->priv;
	192
	193	rhashtable_remove_fast(&priv->ht, &he->node, nft_hash_params);
96518518 PM	194	}
96518518 PM	195
20a69341 PM	196	static void nft_hash_walk(const struct nft_ctx ctx, const struct nft_set set,
20a69341 PM	197	struct nft_set_iter *iter)
96518518	198	{
745f5450	199	struct nft_hash *priv = nft_set_priv(set);
fe2811eb	200	struct nft_hash_elem *he;
9a776628	201	struct rhashtable_iter hti;
20a69341	202	struct nft_set_elem elem;
9a776628	203	int err;
96518518	204
8f6fd83c	205	err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
9a776628 HX	206	iter->err = err;
	207	if (err)
	208	return;
88d6ed15	209
9a776628 HX	210	err = rhashtable_walk_start(&hti);
	211	if (err && err != -EAGAIN) {
	212	iter->err = err;
	213	goto out;
	214	}
	215
	216	while ((he = rhashtable_walk_next(&hti))) {
	217	if (IS_ERR(he)) {
	218	err = PTR_ERR(he);
	219	if (err != -EAGAIN) {
	220	iter->err = err;
	221	goto out;
	222	}
d8bdff59 HX	223
d8bdff59 HX	224	continue;
9a776628 HX	225	}
	226
	227	if (iter->count < iter->skip)
	228	goto cont;
9d098292 PM	229	if (nft_set_elem_expired(&he->ext))
9d098292 PM	230	goto cont;
8588ac09	231	if (!nft_set_elem_active(&he->ext, iter->genmask))
cc02e457	232	goto cont;
20a69341	233
fe2811eb	234	elem.priv = he;
9a776628 HX	235
	236	iter->err = iter->fn(ctx, set, iter, &elem);
	237	if (iter->err < 0)
	238	goto out;
20a69341	239
20a69341	240	cont:
9a776628	241	iter->count++;
96518518	242	}
9a776628 HX	243
	244	out:
	245	rhashtable_walk_stop(&hti);
	246	rhashtable_walk_exit(&hti);
96518518 PM	247	}
96518518 PM	248
9d098292 PM	249	static void nft_hash_gc(struct work_struct *work)
9d098292 PM	250	{
3dd0673a	251	struct nft_set *set;
9d098292 PM	252	struct nft_hash_elem *he;
	253	struct nft_hash *priv;
	254	struct nft_set_gc_batch *gcb = NULL;
	255	struct rhashtable_iter hti;
	256	int err;
	257
	258	priv = container_of(work, struct nft_hash, gc_work.work);
	259	set = nft_set_container_of(priv);
	260
8f6fd83c	261	err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
9d098292 PM	262	if (err)
	263	goto schedule;
	264
	265	err = rhashtable_walk_start(&hti);
	266	if (err && err != -EAGAIN)
	267	goto out;
	268
	269	while ((he = rhashtable_walk_next(&hti))) {
	270	if (IS_ERR(he)) {
	271	if (PTR_ERR(he) != -EAGAIN)
	272	goto out;
	273	continue;
	274	}
	275
	276	if (!nft_set_elem_expired(&he->ext))
	277	continue;
	278	if (nft_set_elem_mark_busy(&he->ext))
	279	continue;
	280
	281	gcb = nft_set_gc_batch_check(set, gcb, GFP_ATOMIC);
	282	if (gcb == NULL)
	283	goto out;
	284	rhashtable_remove_fast(&priv->ht, &he->node, nft_hash_params);
3dd0673a	285	atomic_dec(&set->nelems);
9d098292 PM	286	nft_set_gc_batch_add(gcb, he);
	287	}
	288	out:
	289	rhashtable_walk_stop(&hti);
	290	rhashtable_walk_exit(&hti);
	291
	292	nft_set_gc_batch_complete(gcb);
	293	schedule:
	294	queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
	295	nft_set_gc_interval(set));
	296	}
	297
20a69341 PM	298	static unsigned int nft_hash_privsize(const struct nlattr * const nla[])
20a69341 PM	299	{
745f5450	300	return sizeof(struct nft_hash);
cfe4a9dd TG	301	}
cfe4a9dd TG	302
fa377321	303	static const struct rhashtable_params nft_hash_params = {
45d84751	304	.head_offset = offsetof(struct nft_hash_elem, node),
bfd6e327 PM	305	.hashfn = nft_hash_key,
	306	.obj_hashfn = nft_hash_obj,
	307	.obj_cmpfn = nft_hash_cmp,
45d84751	308	.automatic_shrinking = true,
fa377321 HX	309	};
fa377321 HX	310
20a69341	311	static int nft_hash_init(const struct nft_set *set,
c50b960c	312	const struct nft_set_desc *desc,
96518518 PM	313	const struct nlattr * const tb[])
96518518 PM	314	{
745f5450	315	struct nft_hash *priv = nft_set_priv(set);
fa377321	316	struct rhashtable_params params = nft_hash_params;
9d098292	317	int err;
fa377321 HX	318
fa377321 HX	319	params.nelem_hint = desc->size ?: NFT_HASH_ELEMENT_HINT;
45d84751	320	params.key_len = set->klen;
96518518	321
9d098292 PM	322	err = rhashtable_init(&priv->ht, &params);
	323	if (err < 0)
	324	return err;
	325
	326	INIT_DEFERRABLE_WORK(&priv->gc_work, nft_hash_gc);
	327	if (set->flags & NFT_SET_TIMEOUT)
	328	queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
	329	nft_set_gc_interval(set));
	330	return 0;
96518518 PM	331	}
96518518 PM	332
61edafbb	333	static void nft_hash_elem_destroy(void ptr, void arg)
96518518	334	{
61edafbb	335	nft_set_elem_destroy((const struct nft_set *)arg, ptr);
6b6f302c	336	}
97defe1e	337
6b6f302c TG	338	static void nft_hash_destroy(const struct nft_set *set)
6b6f302c TG	339	{
745f5450 PM	340	struct nft_hash *priv = nft_set_priv(set);
745f5450 PM	341
9d098292	342	cancel_delayed_work_sync(&priv->gc_work);
61edafbb PM	343	rhashtable_free_and_destroy(&priv->ht, nft_hash_elem_destroy,
61edafbb PM	344	(void *)set);
96518518 PM	345	}
96518518 PM	346
c50b960c PM	347	static bool nft_hash_estimate(const struct nft_set_desc *desc, u32 features,
	348	struct nft_set_estimate *est)
	349	{
	350	unsigned int esize;
	351
	352	esize = sizeof(struct nft_hash_elem);
c50b960c	353	if (desc->size) {
745f5450	354	est->size = sizeof(struct nft_hash) +
cfe4a9dd	355	roundup_pow_of_two(desc->size * 4 / 3) *
c50b960c PM	356	sizeof(struct nft_hash_elem *) +
	357	desc->size * esize;
	358	} else {
	359	/* Resizing happens when the load drops below 30% or goes
	360	* above 75%. The average of 52.5% load (approximated by 50%)
	361	* is used for the size estimation of the hash buckets,
	362	* meaning we calculate two buckets per element.
	363	*/
	364	est->size = esize + 2 * sizeof(struct nft_hash_elem *);
	365	}
	366
	367	est->class = NFT_SET_CLASS_O_1;
	368
	369	return true;
	370	}
	371
20a69341 PM	372	static struct nft_set_ops nft_hash_ops __read_mostly = {
20a69341 PM	373	.privsize = nft_hash_privsize,
fe2811eb	374	.elemsize = offsetof(struct nft_hash_elem, ext),
c50b960c	375	.estimate = nft_hash_estimate,
96518518 PM	376	.init = nft_hash_init,
96518518 PM	377	.destroy = nft_hash_destroy,
20a69341	378	.insert = nft_hash_insert,
cc02e457 PM	379	.activate = nft_hash_activate,
cc02e457 PM	380	.deactivate = nft_hash_deactivate,
20a69341 PM	381	.remove = nft_hash_remove,
20a69341 PM	382	.lookup = nft_hash_lookup,
22fe54d5	383	.update = nft_hash_update,
20a69341	384	.walk = nft_hash_walk,
9d098292	385	.features = NFT_SET_MAP \| NFT_SET_TIMEOUT,
20a69341	386	.owner = THIS_MODULE,
96518518 PM	387	};
	388
	389	static int __init nft_hash_module_init(void)
	390	{
20a69341	391	return nft_register_set(&nft_hash_ops);
96518518 PM	392	}
	393
	394	static void __exit nft_hash_module_exit(void)
	395	{
20a69341	396	nft_unregister_set(&nft_hash_ops);
96518518 PM	397	}
	398
	399	module_init(nft_hash_module_init);
	400	module_exit(nft_hash_module_exit);
	401
	402	MODULE_LICENSE("GPL");
	403	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
20a69341	404	MODULE_ALIAS_NFT_SET();