/*
 * Copyright (c) 2016 Adrian Chadd <adrian@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: stable/12/lib/librss/librss.h 306525 2016-09-30 19:59:56Z adrian $
 */

#ifndef	__LIBRSS_H__
#define	__LIBRSS_H__

struct rss_config {
	int rss_ncpus;
	int rss_nbuckets;
	int rss_basecpu;
	int *rss_bucket_map;
};

typedef enum {
	RSS_BUCKET_TYPE_NONE = 0,
	RSS_BUCKET_TYPE_KERNEL_ALL = 1,
	RSS_BUCKET_TYPE_KERNEL_TX = 2,
	RSS_BUCKET_TYPE_KERNEL_RX = 3,
	RSS_BUCKET_TYPE_MAX = 3,
} rss_bucket_type_t;

typedef void rss_bucket_rebalance_cb_t(void *arg);

/*
 * Enable/disable whether to allow for multiple bind()s to the
 * given PCB entry.
 *
 * This must be done before bind().
 */
extern	int rss_sock_set_bindmulti(int fd, int af, int val);

/*
 * Set the RSS bucket for the given file descriptor.
 *
 * This must be done before bind().
 */
extern	int rss_sock_set_rss_bucket(int fd, int af, int rss_bucket);

/*
 * Enable or disable receiving RSS/flowid information on
 * received UDP frames.
 */
extern	int rss_sock_set_recvrss(int fd, int af, int val);

/*
 * Fetch RSS configuration information.
 */
extern	struct rss_config * rss_config_get(void);

/*
 * Free an RSS configuration structure.
 */
extern	void rss_config_free(struct rss_config *rc);

/*
 * Return how many RSS buckets there are.
 */
extern	int rss_config_get_bucket_count(struct rss_config *rc);

/*
 * Fetch the cpuset configuration for the given RSS bucket and
 * type.
 */
extern	int rss_get_bucket_cpuset(struct rss_config *rc,
    rss_bucket_type_t btype, int bucket, cpuset_t *cs);

/*
 * Set a callback for bucket rebalancing.
 *
 * This will occur in a separate thread context rather than
 * a signal handler.
 */
extern	int rss_set_bucket_rebalance_cb(rss_bucket_rebalance_cb_t *cb,
	    void *cbdata);

#endif /* __LIBRSS_H__ */
