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