| 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 | extern int drm_ht_create(struct drm_open_hash *ht, unsigned int order); |
| 53 | extern int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item); |
| 54 | extern 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 | extern int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key, struct drm_hash_item **item); |
| 58 | |
| 59 | extern void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key); |
| 60 | extern int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key); |
| 61 | extern int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item); |
| 62 | extern 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 |