[deliverable/linux.git] / net / netfilter / nft_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 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(read_pnet(&set->pnet)),
		.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 nft_set *set,
			   const struct nft_set_elem *elem)
{
	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(read_pnet(&set->pnet)),
		.set	 = set,
		.key	 = elem->key.val.data,
	};

	return rhashtable_lookup_insert_key(&priv->ht, &arg, &he->node,
					    nft_hash_params);
}

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

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

static void *nft_hash_deactivate(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(read_pnet(&set->pnet)),
		.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_set_elem_change_active(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
8cd8937a	74	static bool nft_hash_lookup(const struct nft_set set, const u32 key,
b2832dd6	75	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 = {
cc02e457	80	.genmask = nft_genmask_cur(read_pnet(&set->pnet)),
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
20a69341 PM	128	static int nft_hash_insert(const struct nft_set *set,
20a69341 PM	129	const struct nft_set_elem *elem)
96518518	130	{
745f5450	131	struct nft_hash *priv = nft_set_priv(set);
fe2811eb	132	struct nft_hash_elem *he = elem->priv;
bfd6e327	133	struct nft_hash_cmp_arg arg = {
cc02e457	134	.genmask = nft_genmask_next(read_pnet(&set->pnet)),
bfd6e327	135	.set = set,
7d740264	136	.key = elem->key.val.data,
bfd6e327	137	};
ce6eb0d7	138
fe2811eb PM	139	return rhashtable_lookup_insert_key(&priv->ht, &arg, &he->node,
fe2811eb PM	140	nft_hash_params);
96518518 PM	141	}
96518518 PM	142
cc02e457 PM	143	static void nft_hash_activate(const struct nft_set *set,
cc02e457 PM	144	const struct nft_set_elem *elem)
96518518	145	{
cc02e457	146	struct nft_hash_elem *he = elem->priv;
ce6eb0d7	147
cc02e457	148	nft_set_elem_change_active(set, &he->ext);
9d098292	149	nft_set_elem_clear_busy(&he->ext);
20a69341	150	}
96518518	151
cc02e457 PM	152	static void nft_hash_deactivate(const struct nft_set set,
cc02e457 PM	153	const struct nft_set_elem *elem)
20a69341	154	{
745f5450	155	struct nft_hash *priv = nft_set_priv(set);
fa377321	156	struct nft_hash_elem *he;
bfd6e327	157	struct nft_hash_cmp_arg arg = {
cc02e457	158	.genmask = nft_genmask_next(read_pnet(&set->pnet)),
bfd6e327	159	.set = set,
7d740264	160	.key = elem->key.val.data,
bfd6e327	161	};
fa377321	162
9d098292	163	rcu_read_lock();
bfd6e327	164	he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params);
9d098292 PM	165	if (he != NULL) {
	166	if (!nft_set_elem_mark_busy(&he->ext))
	167	nft_set_elem_change_active(set, &he->ext);
	168	else
	169	he = NULL;
	170	}
	171	rcu_read_unlock();
8d24c0b4	172
cc02e457 PM	173	return he;
cc02e457 PM	174	}
8d24c0b4	175
cc02e457 PM	176	static void nft_hash_remove(const struct nft_set *set,
	177	const struct nft_set_elem *elem)
	178	{
	179	struct nft_hash *priv = nft_set_priv(set);
	180	struct nft_hash_elem *he = elem->priv;
	181
	182	rhashtable_remove_fast(&priv->ht, &he->node, nft_hash_params);
96518518 PM	183	}
96518518 PM	184
20a69341 PM	185	static void nft_hash_walk(const struct nft_ctx ctx, const struct nft_set set,
20a69341 PM	186	struct nft_set_iter *iter)
96518518	187	{
745f5450	188	struct nft_hash *priv = nft_set_priv(set);
fe2811eb	189	struct nft_hash_elem *he;
9a776628	190	struct rhashtable_iter hti;
20a69341	191	struct nft_set_elem elem;
9a776628	192	int err;
96518518	193
8f6fd83c	194	err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
9a776628 HX	195	iter->err = err;
	196	if (err)
	197	return;
88d6ed15	198
9a776628 HX	199	err = rhashtable_walk_start(&hti);
	200	if (err && err != -EAGAIN) {
	201	iter->err = err;
	202	goto out;
	203	}
	204
	205	while ((he = rhashtable_walk_next(&hti))) {
	206	if (IS_ERR(he)) {
	207	err = PTR_ERR(he);
	208	if (err != -EAGAIN) {
	209	iter->err = err;
	210	goto out;
	211	}
d8bdff59 HX	212
d8bdff59 HX	213	continue;
9a776628 HX	214	}
	215
	216	if (iter->count < iter->skip)
	217	goto cont;
9d098292 PM	218	if (nft_set_elem_expired(&he->ext))
9d098292 PM	219	goto cont;
8588ac09	220	if (!nft_set_elem_active(&he->ext, iter->genmask))
cc02e457	221	goto cont;
20a69341	222
fe2811eb	223	elem.priv = he;
9a776628 HX	224
	225	iter->err = iter->fn(ctx, set, iter, &elem);
	226	if (iter->err < 0)
	227	goto out;
20a69341	228
20a69341	229	cont:
9a776628	230	iter->count++;
96518518	231	}
9a776628 HX	232
	233	out:
	234	rhashtable_walk_stop(&hti);
	235	rhashtable_walk_exit(&hti);
96518518 PM	236	}
96518518 PM	237
9d098292 PM	238	static void nft_hash_gc(struct work_struct *work)
9d098292 PM	239	{
3dd0673a	240	struct nft_set *set;
9d098292 PM	241	struct nft_hash_elem *he;
	242	struct nft_hash *priv;
	243	struct nft_set_gc_batch *gcb = NULL;
	244	struct rhashtable_iter hti;
	245	int err;
	246
	247	priv = container_of(work, struct nft_hash, gc_work.work);
	248	set = nft_set_container_of(priv);
	249
8f6fd83c	250	err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL);
9d098292 PM	251	if (err)
	252	goto schedule;
	253
	254	err = rhashtable_walk_start(&hti);
	255	if (err && err != -EAGAIN)
	256	goto out;
	257
	258	while ((he = rhashtable_walk_next(&hti))) {
	259	if (IS_ERR(he)) {
	260	if (PTR_ERR(he) != -EAGAIN)
	261	goto out;
	262	continue;
	263	}
	264
	265	if (!nft_set_elem_expired(&he->ext))
	266	continue;
	267	if (nft_set_elem_mark_busy(&he->ext))
	268	continue;
	269
	270	gcb = nft_set_gc_batch_check(set, gcb, GFP_ATOMIC);
	271	if (gcb == NULL)
	272	goto out;
	273	rhashtable_remove_fast(&priv->ht, &he->node, nft_hash_params);
3dd0673a	274	atomic_dec(&set->nelems);
9d098292 PM	275	nft_set_gc_batch_add(gcb, he);
	276	}
	277	out:
	278	rhashtable_walk_stop(&hti);
	279	rhashtable_walk_exit(&hti);
	280
	281	nft_set_gc_batch_complete(gcb);
	282	schedule:
	283	queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
	284	nft_set_gc_interval(set));
	285	}
	286
20a69341 PM	287	static unsigned int nft_hash_privsize(const struct nlattr * const nla[])
20a69341 PM	288	{
745f5450	289	return sizeof(struct nft_hash);
cfe4a9dd TG	290	}
cfe4a9dd TG	291
fa377321	292	static const struct rhashtable_params nft_hash_params = {
45d84751	293	.head_offset = offsetof(struct nft_hash_elem, node),
bfd6e327 PM	294	.hashfn = nft_hash_key,
	295	.obj_hashfn = nft_hash_obj,
	296	.obj_cmpfn = nft_hash_cmp,
45d84751	297	.automatic_shrinking = true,
fa377321 HX	298	};
fa377321 HX	299
20a69341	300	static int nft_hash_init(const struct nft_set *set,
c50b960c	301	const struct nft_set_desc *desc,
96518518 PM	302	const struct nlattr * const tb[])
96518518 PM	303	{
745f5450	304	struct nft_hash *priv = nft_set_priv(set);
fa377321	305	struct rhashtable_params params = nft_hash_params;
9d098292	306	int err;
fa377321 HX	307
fa377321 HX	308	params.nelem_hint = desc->size ?: NFT_HASH_ELEMENT_HINT;
45d84751	309	params.key_len = set->klen;
96518518	310
9d098292 PM	311	err = rhashtable_init(&priv->ht, &params);
	312	if (err < 0)
	313	return err;
	314
	315	INIT_DEFERRABLE_WORK(&priv->gc_work, nft_hash_gc);
	316	if (set->flags & NFT_SET_TIMEOUT)
	317	queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
	318	nft_set_gc_interval(set));
	319	return 0;
96518518 PM	320	}
96518518 PM	321
61edafbb	322	static void nft_hash_elem_destroy(void ptr, void arg)
96518518	323	{
61edafbb	324	nft_set_elem_destroy((const struct nft_set *)arg, ptr);
6b6f302c	325	}
97defe1e	326
6b6f302c TG	327	static void nft_hash_destroy(const struct nft_set *set)
6b6f302c TG	328	{
745f5450 PM	329	struct nft_hash *priv = nft_set_priv(set);
745f5450 PM	330
9d098292	331	cancel_delayed_work_sync(&priv->gc_work);
61edafbb PM	332	rhashtable_free_and_destroy(&priv->ht, nft_hash_elem_destroy,
61edafbb PM	333	(void *)set);
96518518 PM	334	}
96518518 PM	335
c50b960c PM	336	static bool nft_hash_estimate(const struct nft_set_desc *desc, u32 features,
	337	struct nft_set_estimate *est)
	338	{
	339	unsigned int esize;
	340
	341	esize = sizeof(struct nft_hash_elem);
c50b960c	342	if (desc->size) {
745f5450	343	est->size = sizeof(struct nft_hash) +
cfe4a9dd	344	roundup_pow_of_two(desc->size * 4 / 3) *
c50b960c PM	345	sizeof(struct nft_hash_elem *) +
	346	desc->size * esize;
	347	} else {
	348	/* Resizing happens when the load drops below 30% or goes
	349	* above 75%. The average of 52.5% load (approximated by 50%)
	350	* is used for the size estimation of the hash buckets,
	351	* meaning we calculate two buckets per element.
	352	*/
	353	est->size = esize + 2 * sizeof(struct nft_hash_elem *);
	354	}
	355
	356	est->class = NFT_SET_CLASS_O_1;
	357
	358	return true;
	359	}
	360
20a69341 PM	361	static struct nft_set_ops nft_hash_ops __read_mostly = {
20a69341 PM	362	.privsize = nft_hash_privsize,
fe2811eb	363	.elemsize = offsetof(struct nft_hash_elem, ext),
c50b960c	364	.estimate = nft_hash_estimate,
96518518 PM	365	.init = nft_hash_init,
96518518 PM	366	.destroy = nft_hash_destroy,
20a69341	367	.insert = nft_hash_insert,
cc02e457 PM	368	.activate = nft_hash_activate,
cc02e457 PM	369	.deactivate = nft_hash_deactivate,
20a69341 PM	370	.remove = nft_hash_remove,
20a69341 PM	371	.lookup = nft_hash_lookup,
22fe54d5	372	.update = nft_hash_update,
20a69341	373	.walk = nft_hash_walk,
9d098292	374	.features = NFT_SET_MAP \| NFT_SET_TIMEOUT,
20a69341	375	.owner = THIS_MODULE,
96518518 PM	376	};
	377
	378	static int __init nft_hash_module_init(void)
	379	{
20a69341	380	return nft_register_set(&nft_hash_ops);
96518518 PM	381	}
	382
	383	static void __exit nft_hash_module_exit(void)
	384	{
20a69341	385	nft_unregister_set(&nft_hash_ops);
96518518 PM	386	}
	387
	388	module_init(nft_hash_module_init);
	389	module_exit(nft_hash_module_exit);
	390
	391	MODULE_LICENSE("GPL");
	392	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
20a69341	393	MODULE_ALIAS_NFT_SET();