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 41 static __inline int 42 hash_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 */ 51 void * 52 hashinit_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 */ 80 void * 81 hashinit(int elements, struct malloc_type *type, u_long *hashmask) 82 { 83 84 return (hashinit_flags(elements, type, hashmask, HASH_WAITOK)); 85 } 86 87 void 88 hashdestroy(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 99 static 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 */ 108 void * 109 phashinit_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 */ 142 void * 143 phashinit(int elements, struct malloc_type *type, u_long *nentries) 144 { 145 146 return (phashinit_flags(elements, type, nentries, HASH_WAITOK)); 147 } 148