Thomas Hellstrom | 3a1bd92 | 2006-08-07 21:30:28 +1000 | [diff] [blame] | 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 | **************************************************************************/ |
| 28 | /* |
| 29 | * Simple open hash tab implementation. |
| 30 | * |
| 31 | * Authors: |
| 32 | * Thomas Hellström <thomas-at-tungstengraphics-dot-com> |
| 33 | */ |
| 34 | |
| 35 | #include "drmP.h" |
| 36 | #include "drm_hashtab.h" |
| 37 | #include <linux/hash.h> |
| 38 | |
| 39 | int drm_ht_create(drm_open_hash_t *ht, unsigned int order) |
| 40 | { |
| 41 | unsigned int i; |
| 42 | |
| 43 | ht->size = 1 << order; |
| 44 | ht->order = order; |
| 45 | ht->fill = 0; |
Dave Airlie | cd839d0 | 2007-02-18 17:14:09 +1100 | [diff] [blame^] | 46 | ht->use_vmalloc = ((ht->size * sizeof(*ht->table)) > PAGE_SIZE); |
| 47 | if (!ht->use_vmalloc) { |
| 48 | ht->table = drm_calloc(ht->size, sizeof(*ht->table), |
| 49 | DRM_MEM_HASHTAB); |
| 50 | } |
| 51 | if (!ht->table) { |
| 52 | ht->use_vmalloc = 1; |
| 53 | ht->table = vmalloc(ht->size*sizeof(*ht->table)); |
| 54 | } |
Thomas Hellstrom | 3a1bd92 | 2006-08-07 21:30:28 +1000 | [diff] [blame] | 55 | if (!ht->table) { |
| 56 | DRM_ERROR("Out of memory for hash table\n"); |
| 57 | return -ENOMEM; |
| 58 | } |
| 59 | for (i=0; i< ht->size; ++i) { |
| 60 | INIT_HLIST_HEAD(&ht->table[i]); |
| 61 | } |
| 62 | return 0; |
| 63 | } |
| 64 | |
| 65 | void drm_ht_verbose_list(drm_open_hash_t *ht, unsigned long key) |
| 66 | { |
| 67 | drm_hash_item_t *entry; |
| 68 | struct hlist_head *h_list; |
| 69 | struct hlist_node *list; |
| 70 | unsigned int hashed_key; |
| 71 | int count = 0; |
| 72 | |
| 73 | hashed_key = hash_long(key, ht->order); |
| 74 | DRM_DEBUG("Key is 0x%08lx, Hashed key is 0x%08x\n", key, hashed_key); |
| 75 | h_list = &ht->table[hashed_key]; |
| 76 | hlist_for_each(list, h_list) { |
| 77 | entry = hlist_entry(list, drm_hash_item_t, head); |
| 78 | DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key); |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | static struct hlist_node *drm_ht_find_key(drm_open_hash_t *ht, |
| 83 | unsigned long key) |
| 84 | { |
| 85 | drm_hash_item_t *entry; |
| 86 | struct hlist_head *h_list; |
| 87 | struct hlist_node *list; |
| 88 | unsigned int hashed_key; |
| 89 | |
| 90 | hashed_key = hash_long(key, ht->order); |
| 91 | h_list = &ht->table[hashed_key]; |
| 92 | hlist_for_each(list, h_list) { |
| 93 | entry = hlist_entry(list, drm_hash_item_t, head); |
| 94 | if (entry->key == key) |
| 95 | return list; |
| 96 | if (entry->key > key) |
| 97 | break; |
| 98 | } |
| 99 | return NULL; |
| 100 | } |
| 101 | |
| 102 | |
| 103 | int drm_ht_insert_item(drm_open_hash_t *ht, drm_hash_item_t *item) |
| 104 | { |
| 105 | drm_hash_item_t *entry; |
| 106 | struct hlist_head *h_list; |
| 107 | struct hlist_node *list, *parent; |
| 108 | unsigned int hashed_key; |
| 109 | unsigned long key = item->key; |
| 110 | |
| 111 | hashed_key = hash_long(key, ht->order); |
| 112 | h_list = &ht->table[hashed_key]; |
| 113 | parent = NULL; |
| 114 | hlist_for_each(list, h_list) { |
| 115 | entry = hlist_entry(list, drm_hash_item_t, head); |
| 116 | if (entry->key == key) |
Thomas Hellstrom | 47cc140 | 2006-09-22 04:04:18 +1000 | [diff] [blame] | 117 | return -EINVAL; |
Thomas Hellstrom | 3a1bd92 | 2006-08-07 21:30:28 +1000 | [diff] [blame] | 118 | if (entry->key > key) |
| 119 | break; |
| 120 | parent = list; |
| 121 | } |
| 122 | if (parent) { |
| 123 | hlist_add_after(parent, &item->head); |
| 124 | } else { |
| 125 | hlist_add_head(&item->head, h_list); |
| 126 | } |
| 127 | return 0; |
| 128 | } |
| 129 | |
| 130 | /* |
| 131 | * Just insert an item and return any "bits" bit key that hasn't been |
| 132 | * used before. |
| 133 | */ |
| 134 | int drm_ht_just_insert_please(drm_open_hash_t *ht, drm_hash_item_t *item, |
| 135 | unsigned long seed, int bits, int shift, |
| 136 | unsigned long add) |
| 137 | { |
| 138 | int ret; |
| 139 | unsigned long mask = (1 << bits) - 1; |
| 140 | unsigned long first, unshifted_key; |
| 141 | |
| 142 | unshifted_key = hash_long(seed, bits); |
| 143 | first = unshifted_key; |
| 144 | do { |
| 145 | item->key = (unshifted_key << shift) + add; |
| 146 | ret = drm_ht_insert_item(ht, item); |
| 147 | if (ret) |
| 148 | unshifted_key = (unshifted_key + 1) & mask; |
| 149 | } while(ret && (unshifted_key != first)); |
| 150 | |
| 151 | if (ret) { |
| 152 | DRM_ERROR("Available key bit space exhausted\n"); |
| 153 | return -EINVAL; |
| 154 | } |
| 155 | return 0; |
| 156 | } |
| 157 | |
| 158 | int drm_ht_find_item(drm_open_hash_t *ht, unsigned long key, |
| 159 | drm_hash_item_t **item) |
| 160 | { |
| 161 | struct hlist_node *list; |
| 162 | |
| 163 | list = drm_ht_find_key(ht, key); |
| 164 | if (!list) |
Thomas Hellstrom | 47cc140 | 2006-09-22 04:04:18 +1000 | [diff] [blame] | 165 | return -EINVAL; |
Thomas Hellstrom | 3a1bd92 | 2006-08-07 21:30:28 +1000 | [diff] [blame] | 166 | |
| 167 | *item = hlist_entry(list, drm_hash_item_t, head); |
| 168 | return 0; |
| 169 | } |
| 170 | |
| 171 | int drm_ht_remove_key(drm_open_hash_t *ht, unsigned long key) |
| 172 | { |
| 173 | struct hlist_node *list; |
| 174 | |
| 175 | list = drm_ht_find_key(ht, key); |
| 176 | if (list) { |
| 177 | hlist_del_init(list); |
| 178 | ht->fill--; |
| 179 | return 0; |
| 180 | } |
Thomas Hellstrom | 47cc140 | 2006-09-22 04:04:18 +1000 | [diff] [blame] | 181 | return -EINVAL; |
Thomas Hellstrom | 3a1bd92 | 2006-08-07 21:30:28 +1000 | [diff] [blame] | 182 | } |
| 183 | |
| 184 | int drm_ht_remove_item(drm_open_hash_t *ht, drm_hash_item_t *item) |
| 185 | { |
| 186 | hlist_del_init(&item->head); |
| 187 | ht->fill--; |
| 188 | return 0; |
| 189 | } |
| 190 | |
| 191 | void drm_ht_remove(drm_open_hash_t *ht) |
| 192 | { |
| 193 | if (ht->table) { |
Dave Airlie | cd839d0 | 2007-02-18 17:14:09 +1100 | [diff] [blame^] | 194 | if (ht->use_vmalloc) |
| 195 | vfree(ht->table); |
| 196 | else |
| 197 | drm_free(ht->table, ht->size * sizeof(*ht->table), |
| 198 | DRM_MEM_HASHTAB); |
Thomas Hellstrom | 3a1bd92 | 2006-08-07 21:30:28 +1000 | [diff] [blame] | 199 | ht->table = NULL; |
| 200 | } |
| 201 | } |
| 202 | |