1 /* $NetBSD: drm_hashtab.h,v 1.4 2021/12/18 23:45:46 riastradh Exp $ */ 2 3 /************************************************************************** 4 * 5 * Copyright 2006 Tungsten Graphics, Inc., Bismack, ND. USA. 6 * All Rights Reserved. 7 * 8 * Permission is hereby granted, free of charge, to any person obtaining a 9 * copy of this software and associated documentation files (the 10 * "Software"), to deal in the Software without restriction, including 11 * without limitation the rights to use, copy, modify, merge, publish, 12 * distribute, sub license, and/or sell copies of the Software, and to 13 * permit persons to whom the Software is furnished to do so, subject to 14 * the following conditions: 15 * 16 * The above copyright notice and this permission notice (including the 17 * next paragraph) shall be included in all copies or substantial portions 18 * of the Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 23 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 24 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 25 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 26 * USE OR OTHER DEALINGS IN THE SOFTWARE. 27 * 28 * 29 **************************************************************************/ 30 /* 31 * Simple open hash tab implementation. 32 * 33 * Authors: 34 * Thomas Hellström <thomas-at-tungstengraphics-dot-com> 35 */ 36 37 #ifndef DRM_HASHTAB_H 38 #define DRM_HASHTAB_H 39 40 #include <linux/kernel.h> 41 #include <linux/list.h> 42 #include <linux/types.h> 43 44 #define drm_hash_entry(_ptr, _type, _member) container_of(_ptr, _type, _member) 45 46 struct drm_hash_item { 47 struct hlist_node head; 48 unsigned long key; 49 }; 50 51 struct drm_open_hash { 52 struct hlist_head *table; 53 u8 order; 54 }; 55 56 int drm_ht_create(struct drm_open_hash *ht, unsigned int order); 57 int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item); 58 int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item, 59 unsigned long seed, int bits, int shift, 60 unsigned long add); 61 int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key, struct drm_hash_item **item); 62 63 void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key); 64 int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key); 65 int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item); 66 void drm_ht_remove(struct drm_open_hash *ht); 67 68 /* 69 * RCU-safe interface 70 * 71 * The user of this API needs to make sure that two or more instances of the 72 * hash table manipulation functions are never run simultaneously. 73 * The lookup function drm_ht_find_item_rcu may, however, run simultaneously 74 * with any of the manipulation functions as long as it's called from within 75 * an RCU read-locked section. 76 */ 77 #define drm_ht_insert_item_rcu drm_ht_insert_item 78 #define drm_ht_just_insert_please_rcu drm_ht_just_insert_please 79 #define drm_ht_remove_key_rcu drm_ht_remove_key 80 #define drm_ht_remove_item_rcu drm_ht_remove_item 81 #define drm_ht_find_item_rcu drm_ht_find_item 82 83 #endif 84