1 /* $NetBSD: hashtable.h,v 1.5 2018/08/27 06:39:27 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2018 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _LINUX_HASHTABLE_H_ 33 #define _LINUX_HASHTABLE_H_ 34 35 #include <linux/list.h> 36 #include <linux/types.h> 37 #include <linux/kernel.h> 38 #include <linux/hash.h> 39 #include <linux/rculist.h> 40 41 #define DECLARE_HASHTABLE(name, bits) \ 42 struct hlist_head name[1u << (bits)] 43 44 static inline void 45 __hash_init(struct hlist_head *hash, unsigned n) 46 { 47 48 while (n --> 0) 49 INIT_HLIST_HEAD(&hash[n]); 50 } 51 52 static inline bool 53 __hash_empty(struct hlist_head *hash, unsigned n) 54 { 55 56 while (n --> 0) { 57 if (!hlist_empty(&hash[n])) 58 return false; 59 } 60 61 return true; 62 } 63 64 #define __arraycount(array) NELEM(array) 65 66 #define hash_init(h) __hash_init((h), __arraycount(h)) 67 #define hash_add(h, n, k) hlist_add_head(n, &(h)[(k) % __arraycount(h)]) 68 #define hash_del(n) hlist_del_init(n) 69 #define hash_empty(h) __hash_empty((h), __arraycount(h)) 70 71 #define hash_for_each_possible(h, n, f, k) \ 72 hlist_for_each_entry(n, &(h)[(k) % __arraycount(h)], f) 73 74 #define hash_for_each_safe(h, i, t, n, f) \ 75 for ((i) = 0; (i) < __arraycount(h); (i)++) \ 76 hlist_for_each_entry_safe(n, t, &(h)[i], f) 77 78 #endif /*_LINUX_HASHTABLE_H_*/ 79