master
  1/*-
  2 * SPDX-License-Identifier: BSD-2-Clause
  3 *
  4 * Copyright (c) 2020 Alexander V. Chernikov
  5 *
  6 * Redistribution and use in source and binary forms, with or without
  7 * modification, are permitted provided that the following conditions
  8 * are met:
  9 * 1. Redistributions of source code must retain the above copyright
 10 *    notice, this list of conditions and the following disclaimer.
 11 * 2. Redistributions in binary form must reproduce the above copyright
 12 *    notice, this list of conditions and the following disclaimer in the
 13 *    documentation and/or other materials provided with the distribution.
 14 *
 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 25 * SUCH DAMAGE.
 26 */
 27
 28#ifndef	_NET_ROUTE_NHOP_UTILS_H_
 29#define	_NET_ROUTE_NHOP_UTILS_H_
 30
 31/* Chained hash table */
 32struct _cht_head {
 33	uint32_t	hash_size;
 34	uint32_t	items_count;
 35	void		**ptr;
 36};
 37
 38static inline uint32_t
 39_cht_get_resize_size(const struct _cht_head *head)
 40{
 41	uint32_t new_size = 0;
 42
 43	if ((head->items_count * 2 > head->hash_size) && (head->hash_size < 65536))
 44		new_size = head->hash_size * 2;
 45	else if ((head->items_count * 4 < head->hash_size) && head->hash_size > 16)
 46		new_size = head->hash_size / 2;
 47
 48	return (new_size);
 49}
 50
 51static inline int
 52_cht_need_resize(const struct _cht_head *head)
 53{
 54
 55	return (_cht_get_resize_size(head) > 0);
 56}
 57
 58#ifndef	typeof
 59#define	typeof	__typeof
 60#endif
 61
 62#define	CHT_SLIST_NEED_RESIZE(_head)		\
 63	_cht_need_resize((const struct _cht_head *)(_head))
 64#define	CHT_SLIST_GET_RESIZE_BUCKETS(_head)	\
 65	_cht_get_resize_size((const struct _cht_head *)(_head))
 66#define	CHT_SLIST_GET_RESIZE_SIZE(_buckets)	((_buckets) * sizeof(void *))
 67
 68#define	CHT_SLIST_DEFINE(_HNAME, _ITEM_TYPE)	\
 69struct _HNAME##_head {				\
 70	uint32_t	hash_size;		\
 71	uint32_t	items_count;		\
 72	_ITEM_TYPE	**ptr;			\
 73}
 74
 75#define	CHT_SLIST_INIT(_head, _ptr, _num_buckets)	\
 76	(_head)->hash_size = _num_buckets;		\
 77	(_head)->items_count = 0;			\
 78	(_head)->ptr = _ptr;
 79
 80/* Default hash method for constant-size keys */
 81
 82#define	CHT_GET_BUCK(_head, _PX, _key)	_PX##_hash_key(_key) & ((_head)->hash_size - 1)
 83#define	CHT_GET_BUCK_OBJ(_head, _PX, _obj)	_PX##_hash_obj(_obj) & ((_head)->hash_size - 1)
 84
 85#define	CHT_FIRST(_head, idx)	_CHT_FIRST((_head)->ptr, idx)
 86#define	_CHT_FIRST(_ptr, idx)	(_ptr)[idx]
 87
 88#define	CHT_SLIST_FIND(_head, _PX, _key, _ret) do {			\
 89	uint32_t _buck = CHT_GET_BUCK(_head, _PX, _key);		\
 90	_ret = CHT_FIRST(_head, _buck);					\
 91	for ( ; _ret != NULL; _ret = _PX##_next(_ret)) {		\
 92		if (_PX##_cmp(_key, (_ret)))				\
 93			break;						\
 94	}								\
 95} while(0)
 96
 97/*
 98 * hash_obj, nhop_cmp
 99 */
100#define	CHT_SLIST_FIND_BYOBJ(_head, _PX, _obj, _ret) do {		\
101	uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj);		\
102	_ret = CHT_FIRST(_head, _buck);					\
103	for ( ; _ret != NULL; _ret = _PX##_next(_ret)) {		\
104		if (_PX##_cmp(_obj, _ret))				\
105			break;						\
106	}								\
107} while(0)
108
109#define	CHT_SLIST_INSERT_HEAD(_head, _PX, _obj) do {			\
110	uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj);		\
111	_PX##_next(_obj) = CHT_FIRST(_head, _buck);			\
112	CHT_FIRST(_head, _buck) = _obj;					\
113	(_head)->items_count++;						\
114} while(0)
115
116#define	CHT_SLIST_REMOVE(_head, _PX, _obj, _ret) do {			\
117	typeof(*(_head)->ptr) _tmp;					\
118	uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj);		\
119	_ret = CHT_FIRST(_head, _buck);					\
120	_tmp = NULL;							\
121	for ( ; _ret != NULL; _tmp = _ret, _ret = _PX##_next(_ret)) {	\
122		if (_obj == _ret)					\
123			break;						\
124	}								\
125	if (_ret != NULL) {						\
126		if (_tmp == NULL)					\
127			CHT_FIRST(_head, _buck) = _PX##_next(_ret);	\
128		else							\
129			_PX##_next(_tmp) = _PX##_next(_ret);		\
130		(_head)->items_count--;					\
131	}								\
132} while(0)
133#define	CHT_SLIST_REMOVE_BYOBJ	CHT_SLIST_REMOVE
134
135#define	CHT_SLIST_FOREACH(_head, _PX, _x)				\
136	for (uint32_t _i = 0; _i < (_head)->hash_size; _i++) {		\
137		for (_x = CHT_FIRST(_head, _i); _x; _x = _PX##_next(_x))
138#define	CHT_SLIST_FOREACH_END	}
139
140#define	CHT_SLIST_FOREACH_SAFE(_head, _PX, _x, _tmp)			\
141	for (uint32_t _i = 0; _i < (_head)->hash_size; _i++) {		\
142		for (_x = CHT_FIRST(_head, _i); (_tmp = _PX##_next(_x), _x); _x = _tmp)
143#define	CHT_SLIST_FOREACH_SAFE_END	}
144
145#define	CHT_SLIST_RESIZE(_head, _PX, _new_void_ptr, _new_hsize)		\
146	uint32_t _new_idx;						\
147	typeof((_head)->ptr) _new_ptr = (void *)_new_void_ptr;		\
148	typeof(*(_head)->ptr) _x, _y;					\
149	for (uint32_t _old_idx = 0; _old_idx < (_head)->hash_size; _old_idx++) {\
150		_x = CHT_FIRST(_head, _old_idx);			\
151		_y = _x;						\
152		while (_y != NULL) {					\
153			_y = _PX##_next(_x);				\
154			_new_idx = _PX##_hash_obj(_x) & (_new_hsize - 1);\
155			_PX##_next(_x) = _CHT_FIRST(_new_ptr, _new_idx);\
156			_CHT_FIRST(_new_ptr, _new_idx) = _x;		\
157			_x = _y;					\
158		}							\
159	}								\
160	(_head)->hash_size = _new_hsize;				\
161	_new_void_ptr = (void *)(_head)->ptr;				\
162	(_head)->ptr = _new_ptr;
163
164/* bitmasks */
165
166struct bitmask_head {
167	uint16_t	free_off; /* index of the first potentially free block */
168	uint16_t	blocks; /* number of 4/8-byte blocks in the index */
169	uint32_t	items_count; /* total number of items */
170	u_long		*idx;
171};
172
173size_t bitmask_get_size(uint32_t items);
174uint32_t bitmask_get_resize_items(const struct bitmask_head *nh);
175int bitmask_should_resize(const struct bitmask_head *bh);
176void bitmask_swap(struct bitmask_head *bh, void *new_idx, uint32_t new_items, void **pidx);
177void bitmask_init(struct bitmask_head *bh, void *idx, uint32_t num_items);
178int bitmask_copy(const struct bitmask_head *bi, void *new_idx, uint32_t new_items);
179int bitmask_alloc_idx(struct bitmask_head *bi, uint16_t *pidx);
180int bitmask_free_idx(struct bitmask_head *bi, uint16_t idx);
181
182#endif