1 /* 2 * Copyright 2006 Tungsten Graphics, Inc., Bismack, ND. USA. 3 * All Rights Reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the 7 * "Software"), to deal in the Software without restriction, including 8 * without limitation the rights to use, copy, modify, merge, publish, 9 * distribute, sub license, and/or sell copies of the Software, and to 10 * permit persons to whom the Software is furnished to do so, subject to 11 * the following conditions: 12 * 13 * The above copyright notice and this permission notice (including the 14 * next paragraph) shall be included in all copies or substantial portions 15 * of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 20 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 21 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 22 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 23 * USE OR OTHER DEALINGS IN THE SOFTWARE. 24 */ 25 26 /* 27 * Simple open hash tab implementation. 28 * 29 * Authors: 30 * Thomas Hellström <thomas-at-tungstengraphics-dot-com> 31 */ 32 33 /* 34 * TODO: Replace this hashtable with Linux' generic implementation 35 * from <linux/hashtable.h>. 36 */ 37 38 #ifndef VMWGFX_HASHTAB_H 39 #define VMWGFX_HASHTAB_H 40 41 #include <linux/list.h> 42 43 #define drm_hash_entry(_ptr, _type, _member) container_of(_ptr, _type, _member) 44 45 struct vmwgfx_hash_item { 46 struct hlist_node head; 47 unsigned long key; 48 }; 49 50 struct vmwgfx_open_hash { 51 struct hlist_head *table; 52 u8 order; 53 }; 54 55 int vmwgfx_ht_create(struct vmwgfx_open_hash *ht, unsigned int order); 56 int vmwgfx_ht_insert_item(struct vmwgfx_open_hash *ht, struct vmwgfx_hash_item *item); 57 int vmwgfx_ht_just_insert_please(struct vmwgfx_open_hash *ht, struct vmwgfx_hash_item *item, 58 unsigned long seed, int bits, int shift, 59 unsigned long add); 60 int vmwgfx_ht_find_item(struct vmwgfx_open_hash *ht, unsigned long key, 61 struct vmwgfx_hash_item **item); 62 63 void vmwgfx_ht_verbose_list(struct vmwgfx_open_hash *ht, unsigned long key); 64 int vmwgfx_ht_remove_key(struct vmwgfx_open_hash *ht, unsigned long key); 65 int vmwgfx_ht_remove_item(struct vmwgfx_open_hash *ht, struct vmwgfx_hash_item *item); 66 void vmwgfx_ht_remove(struct vmwgfx_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 vmwgfx_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 vmwgfx_ht_insert_item_rcu vmwgfx_ht_insert_item 78 #define vmwgfx_ht_just_insert_please_rcu vmwgfx_ht_just_insert_please 79 #define vmwgfx_ht_remove_key_rcu vmwgfx_ht_remove_key 80 #define vmwgfx_ht_remove_item_rcu vmwgfx_ht_remove_item 81 #define vmwgfx_ht_find_item_rcu vmwgfx_ht_find_item 82 83 #endif 84