1 /************************************************************************** 2 * 3 * Copyright 2006 Tungsten Graphics, Inc., Bismarck, 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 * __FBSDID("$FreeBSD: src/sys/dev/drm/drm_hashtab.c,v 1.1 2010/01/31 14:25:29 rnoland Exp $"); 28 **************************************************************************/ 29 30 /* 31 * Simple open hash tab implementation. 32 * 33 * Authors: 34 * Thomas Hellström <thomas-at-tungstengraphics-dot-com> 35 */ 36 37 #include "dev/drm/drmP.h" 38 #include "dev/drm/drm_hashtab.h" 39 40 #if defined(__DragonFly__) 41 #include "dev/drm/drm_priv_hash.h" 42 #else 43 #include <sys/hash.h> 44 #endif 45 46 int drm_ht_create(struct drm_open_hash *ht, unsigned int order) 47 { 48 ht->size = 1 << order; 49 ht->order = order; 50 ht->table = NULL; 51 ht->table = drm_hashinit(ht->size, DRM_MEM_HASHTAB, &ht->mask); 52 if (!ht->table) { 53 DRM_ERROR("Out of memory for hash table\n"); 54 return -ENOMEM; 55 } 56 return 0; 57 } 58 59 void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key) 60 { 61 struct drm_hash_item *entry; 62 struct drm_hash_item_list *h_list; 63 unsigned int hashed_key; 64 int count = 0; 65 66 hashed_key = hash32_buf(&key, sizeof(key), ht->order); 67 DRM_DEBUG("Key is 0x%08lx, Hashed key is 0x%08x\n", key, hashed_key); 68 h_list = &ht->table[hashed_key & ht->mask]; 69 LIST_FOREACH(entry, h_list, head) 70 DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key); 71 } 72 73 static struct drm_hash_item * 74 drm_ht_find_key(struct drm_open_hash *ht, unsigned long key) 75 { 76 struct drm_hash_item *entry; 77 struct drm_hash_item_list *h_list; 78 unsigned int hashed_key; 79 80 hashed_key = hash32_buf(&key, sizeof(key), ht->order); 81 h_list = &ht->table[hashed_key & ht->mask]; 82 LIST_FOREACH(entry, h_list, head) { 83 if (entry->key == key) 84 return entry; 85 if (entry->key > key) 86 break; 87 } 88 return NULL; 89 } 90 91 92 int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item) 93 { 94 struct drm_hash_item *entry, *parent; 95 struct drm_hash_item_list *h_list; 96 unsigned int hashed_key; 97 unsigned long key = item->key; 98 99 hashed_key = hash32_buf(&key, sizeof(key), ht->order); 100 h_list = &ht->table[hashed_key & ht->mask]; 101 parent = NULL; 102 LIST_FOREACH(entry, h_list, head) { 103 if (entry->key == key) 104 return -EINVAL; 105 if (entry->key > key) 106 break; 107 parent = entry; 108 } 109 if (parent) { 110 LIST_INSERT_AFTER(parent, item, head); 111 } else { 112 LIST_INSERT_HEAD(h_list, item, head); 113 } 114 return 0; 115 } 116 117 /* 118 * Just insert an item and return any "bits" bit key that hasn't been 119 * used before. 120 */ 121 int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item, 122 unsigned long seed, int bits, int shift, 123 unsigned long add) 124 { 125 int ret; 126 unsigned long mask = (1 << bits) - 1; 127 unsigned long first, unshifted_key = 0; 128 129 unshifted_key = hash32_buf(&seed, sizeof(seed), unshifted_key); 130 first = unshifted_key; 131 do { 132 item->key = (unshifted_key << shift) + add; 133 ret = drm_ht_insert_item(ht, item); 134 if (ret) 135 unshifted_key = (unshifted_key + 1) & mask; 136 } while(ret && (unshifted_key != first)); 137 138 if (ret) { 139 DRM_ERROR("Available key bit space exhausted\n"); 140 return -EINVAL; 141 } 142 return 0; 143 } 144 145 int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key, 146 struct drm_hash_item **item) 147 { 148 struct drm_hash_item *entry; 149 150 entry = drm_ht_find_key(ht, key); 151 if (!entry) 152 return -EINVAL; 153 154 *item = entry; 155 return 0; 156 } 157 158 int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key) 159 { 160 struct drm_hash_item *entry; 161 162 entry = drm_ht_find_key(ht, key); 163 if (entry) { 164 LIST_REMOVE(entry, head); 165 return 0; 166 } 167 return -EINVAL; 168 } 169 170 int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item) 171 { 172 LIST_REMOVE(item, head); 173 return 0; 174 } 175 176 void drm_ht_remove(struct drm_open_hash *ht) 177 { 178 if (ht->table) { 179 drm_hashdestroy(ht->table, DRM_MEM_HASHTAB, ht->mask); 180 ht->table = NULL; 181 } 182 } 183