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/cdefs.h> 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/malloc.h> 41 42 static __inline int 43 hash_mflags(int flags) 44 { 45 46 return ((flags & HASH_NOWAIT) ? M_NOWAIT : M_WAITOK); 47 } 48 49 /* 50 * General routine to allocate a hash table with control of memory flags. 51 */ 52 void * 53 hashinit_flags(int elements, struct malloc_type *type, u_long *hashmask, 54 int flags) 55 { 56 long hashsize, i; 57 LIST_HEAD(generic, generic) *hashtbl; 58 59 KASSERT(elements > 0, ("%s: bad elements", __func__)); 60 /* Exactly one of HASH_WAITOK and HASH_NOWAIT must be set. */ 61 KASSERT((flags & HASH_WAITOK) ^ (flags & HASH_NOWAIT), 62 ("Bad flags (0x%x) passed to hashinit_flags", flags)); 63 64 for (hashsize = 1; hashsize <= elements; hashsize <<= 1) 65 continue; 66 hashsize >>= 1; 67 68 hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, 69 hash_mflags(flags)); 70 if (hashtbl != NULL) { 71 for (i = 0; i < hashsize; i++) 72 LIST_INIT(&hashtbl[i]); 73 *hashmask = hashsize - 1; 74 } 75 return (hashtbl); 76 } 77 78 /* 79 * Allocate and initialize a hash table with default flag: may sleep. 80 */ 81 void * 82 hashinit(int elements, struct malloc_type *type, u_long *hashmask) 83 { 84 85 return (hashinit_flags(elements, type, hashmask, HASH_WAITOK)); 86 } 87 88 void 89 hashdestroy(void *vhashtbl, struct malloc_type *type, u_long hashmask) 90 { 91 LIST_HEAD(generic, generic) *hashtbl, *hp; 92 93 hashtbl = vhashtbl; 94 for (hp = hashtbl; hp <= &hashtbl[hashmask]; hp++) 95 KASSERT(LIST_EMPTY(hp), ("%s: hashtbl %p not empty " 96 "(malloc type %s)", __func__, hashtbl, type->ks_shortdesc)); 97 free(hashtbl, type); 98 } 99 100 static const int primes[] = { 1, 13, 31, 61, 127, 251, 509, 761, 1021, 1531, 101 2039, 2557, 3067, 3583, 4093, 4603, 5119, 5623, 6143, 102 6653, 7159, 7673, 8191, 12281, 16381, 24571, 32749 }; 103 #define NPRIMES nitems(primes) 104 105 /* 106 * General routine to allocate a prime number sized hash table with control of 107 * memory flags. 108 */ 109 void * 110 phashinit_flags(int elements, struct malloc_type *type, u_long *nentries, int flags) 111 { 112 long hashsize, i; 113 LIST_HEAD(generic, generic) *hashtbl; 114 115 KASSERT(elements > 0, ("%s: bad elements", __func__)); 116 /* Exactly one of HASH_WAITOK and HASH_NOWAIT must be set. */ 117 KASSERT((flags & HASH_WAITOK) ^ (flags & HASH_NOWAIT), 118 ("Bad flags (0x%x) passed to phashinit_flags", flags)); 119 120 for (i = 1, hashsize = primes[1]; hashsize <= elements;) { 121 i++; 122 if (i == NPRIMES) 123 break; 124 hashsize = primes[i]; 125 } 126 hashsize = primes[i - 1]; 127 128 hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, 129 hash_mflags(flags)); 130 if (hashtbl == NULL) 131 return (NULL); 132 133 for (i = 0; i < hashsize; i++) 134 LIST_INIT(&hashtbl[i]); 135 *nentries = hashsize; 136 return (hashtbl); 137 } 138 139 /* 140 * Allocate and initialize a prime number sized hash table with default flag: 141 * may sleep. 142 */ 143 void * 144 phashinit(int elements, struct malloc_type *type, u_long *nentries) 145 { 146 147 return (phashinit_flags(elements, type, nentries, HASH_WAITOK)); 148 } 149