Re: [PATCH RFC nf-next 07/12] netfilter: ipset: add rhashtable boilerplate stubs

Hi Florian,

On Tue, 14 Jul 2026, Florian Westphal wrote:

> Preparation patch.  Adds an rhashtable to the set and initialised
> and destroys it.  No elements are ever added to this hashtable.
>
> This change is supposed to be devoid of side effects and is
> separate to reduce size of the conversion patch.
> +/* 0 = key matches object (equal), non-zero = not equal */
> +static int mtype_rht_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
> +{
> +	const struct mtype_rht_elem *e = obj;
> +	u32 multi = 0;
> +
> +	return !mtype_data_equal(&e->elem,
> +				 (const struct mtype_elem *)arg->key, &multi);
> +}

It does not belong to this patch, but the "multi" arg of 
mtype_data_equal() is needed only for the netiface type: it supports the 
same ip/cidr behind multiple interfaces but the element can store a single 
interface only. The "multi" flag made possible to take into account 
multiple interfaces properly when growing the array in the hash.

The interfaces should be stored in a linked list at element level and the 
"multi" arg of mtype_data_equal() can be removed, which is not needed in 
rhashtable anyway.

Best regards,
Jozsef