src/sys/net/art.h

113 lines
3.8 KiB
C

/* $OpenBSD: art.h,v 1.25 2023/11/11 12:17:50 bluhm Exp $ */
/*
* Copyright (c) 2015 Martin Pieuchot
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef _NET_ART_H_
#define _NET_ART_H_
#include <sys/rwlock.h>
#include <sys/srp.h>
#define ART_MAXLVL 32 /* We currently use 32 levels for IPv6. */
/*
* Root of the ART tables, equivalent to the radix head.
*
* Locks used to protect struct members in this file:
* I immutable after creation
* l root's `ar_lock'
* K kernel lock
* For SRP related structures that allow lock-free reads, the write lock
* is indicated below.
*/
struct art_root {
struct srp ar_root; /* [l] First table */
struct rwlock ar_lock; /* [] Serialise modifications */
uint8_t ar_bits[ART_MAXLVL]; /* [I] Per level stride */
uint8_t ar_nlvl; /* [I] Number of levels */
uint8_t ar_alen; /* [I] Address length in bits */
uint8_t ar_off; /* [I] Offset of key in bytes */
struct sockaddr *ar_source; /* [N] use optional src addr */
};
#define ISLEAF(e) (((unsigned long)(e) & 1) == 0)
#define SUBTABLE(e) ((struct art_table *)((unsigned long)(e) & ~1))
#define ASNODE(t) ((struct art_node *)((unsigned long)(t) | 1))
/*
* Allotment Table.
*/
struct art_table {
struct art_table *at_parent; /* Parent table */
uint32_t at_index; /* Index in the parent table */
uint32_t at_minfringe; /* Index that fringe begins */
uint32_t at_level; /* Level of the table */
uint8_t at_bits; /* Stride length of the table */
uint8_t at_offset; /* Sum of parents' stride len */
/*
* Items stored in the heap are pointers to nodes, in the leaf
* case, or tables otherwise. One exception is index 0 which
* is a route counter.
*/
union {
struct srp node;
unsigned long count;
} *at_heap; /* Array of 2^(slen+1) items */
};
#define at_refcnt at_heap[0].count/* Refcounter (1 per different route) */
#define at_default at_heap[1].node /* Default route (was in parent heap) */
/* Heap size for an ART table of stride length ``slen''. */
#define AT_HEAPSIZE(slen) ((1 << ((slen) + 1)) * sizeof(void *))
/*
* Forward declaration needed for the list of mpath routes
* attached to a single ART node.
*/
struct rtentry;
/*
* A node is the internal representation of a route entry.
*/
struct art_node {
union {
SRPL_HEAD(, rtentry) an__rtlist; /* Route related to this node */
struct art_node *an__gc; /* Entry on GC list */
} an_pointer;
uint8_t an_plen; /* Prefix length */
};
#define an_rtlist an_pointer.an__rtlist
#define an_gc an_pointer.an__gc
void art_init(void);
struct art_root *art_alloc(unsigned int, unsigned int, unsigned int);
struct art_node *art_insert(struct art_root *, struct art_node *, const void *,
int);
struct art_node *art_delete(struct art_root *, struct art_node *, const void *,
int);
struct art_node *art_match(struct art_root *, const void *, struct srp_ref *);
struct art_node *art_lookup(struct art_root *, const void *, int,
struct srp_ref *);
int art_walk(struct art_root *,
int (*)(struct art_node *, void *), void *);
struct art_node *art_get(uint8_t);
void art_put(struct art_node *);
#endif /* _NET_ART_H_ */