1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/malloc.h>
40
41static __inline int
42hash_mflags(int flags)
43{
44
45	return ((flags & HASH_NOWAIT) ? M_NOWAIT : M_WAITOK);
46}
47
48/*
49 * General routine to allocate a hash table with control of memory flags.
50 */
51void *
52hashinit_flags(int elements, struct malloc_type *type, u_long *hashmask,
53    int flags)
54{
55	long hashsize, i;
56	LIST_HEAD(generic, generic) *hashtbl;
57
58	KASSERT(elements > 0, ("%s: bad elements", __func__));
59	/* Exactly one of HASH_WAITOK and HASH_NOWAIT must be set. */
60	KASSERT((flags & HASH_WAITOK) ^ (flags & HASH_NOWAIT),
61	    ("Bad flags (0x%x) passed to hashinit_flags", flags));
62
63	for (hashsize = 1; hashsize <= elements; hashsize <<= 1)
64		continue;
65	hashsize >>= 1;
66
67	hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type,
68	    hash_mflags(flags));
69	if (hashtbl != NULL) {
70		for (i = 0; i < hashsize; i++)
71			LIST_INIT(&hashtbl[i]);
72		*hashmask = hashsize - 1;
73	}
74	return (hashtbl);
75}
76
77/*
78 * Allocate and initialize a hash table with default flag: may sleep.
79 */
80void *
81hashinit(int elements, struct malloc_type *type, u_long *hashmask)
82{
83
84	return (hashinit_flags(elements, type, hashmask, HASH_WAITOK));
85}
86
87void
88hashdestroy(void *vhashtbl, struct malloc_type *type, u_long hashmask)
89{
90	LIST_HEAD(generic, generic) *hashtbl, *hp;
91
92	hashtbl = vhashtbl;
93	for (hp = hashtbl; hp <= &hashtbl[hashmask]; hp++)
94		KASSERT(LIST_EMPTY(hp), ("%s: hashtbl %p not empty "
95		    "(malloc type %s)", __func__, hashtbl, type->ks_shortdesc));
96	free(hashtbl, type);
97}
98
99static const int primes[] = { 1, 13, 31, 61, 127, 251, 509, 761, 1021, 1531,
100			2039, 2557, 3067, 3583, 4093, 4603, 5119, 5623, 6143,
101			6653, 7159, 7673, 8191, 12281, 16381, 24571, 32749 };
102#define	NPRIMES nitems(primes)
103
104/*
105 * General routine to allocate a prime number sized hash table with control of
106 * memory flags.
107 */
108void *
109phashinit_flags(int elements, struct malloc_type *type, u_long *nentries, int flags)
110{
111	long hashsize, i;
112	LIST_HEAD(generic, generic) *hashtbl;
113
114	KASSERT(elements > 0, ("%s: bad elements", __func__));
115	/* Exactly one of HASH_WAITOK and HASH_NOWAIT must be set. */
116	KASSERT((flags & HASH_WAITOK) ^ (flags & HASH_NOWAIT),
117	    ("Bad flags (0x%x) passed to phashinit_flags", flags));
118
119	for (i = 1, hashsize = primes[1]; hashsize <= elements;) {
120		i++;
121		if (i == NPRIMES)
122			break;
123		hashsize = primes[i];
124	}
125	hashsize = primes[i - 1];
126
127	hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type,
128	    hash_mflags(flags));
129	if (hashtbl == NULL)
130		return (NULL);
131
132	for (i = 0; i < hashsize; i++)
133		LIST_INIT(&hashtbl[i]);
134	*nentries = hashsize;
135	return (hashtbl);
136}
137
138/*
139 * Allocate and initialize a prime number sized hash table with default flag:
140 * may sleep.
141 */
142void *
143phashinit(int elements, struct malloc_type *type, u_long *nentries)
144{
145
146	return (phashinit_flags(elements, type, nentries, HASH_WAITOK));
147}
148