blob: ac35145c3e20b279e7b17c1bdf40e9f442fc4fe1 [file] [log] [blame]
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +10001/**************************************************************************
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:
Jan Engelhardt96de0e22007-10-19 23:21:04 +020032 * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100033 */
34
35#include "drmP.h"
36#include "drm_hashtab.h"
37#include <linux/hash.h>
38
Dave Airliee0be4282007-07-12 10:26:44 +100039int drm_ht_create(struct drm_open_hash *ht, unsigned int order)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100040{
41 unsigned int i;
42
43 ht->size = 1 << order;
44 ht->order = order;
45 ht->fill = 0;
Dave Airliec1185cc2007-02-18 18:23:11 +110046 ht->table = NULL;
Dave Airliecd839d02007-02-18 17:14:09 +110047 ht->use_vmalloc = ((ht->size * sizeof(*ht->table)) > PAGE_SIZE);
48 if (!ht->use_vmalloc) {
49 ht->table = drm_calloc(ht->size, sizeof(*ht->table),
50 DRM_MEM_HASHTAB);
51 }
52 if (!ht->table) {
53 ht->use_vmalloc = 1;
54 ht->table = vmalloc(ht->size*sizeof(*ht->table));
55 }
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100056 if (!ht->table) {
57 DRM_ERROR("Out of memory for hash table\n");
58 return -ENOMEM;
59 }
60 for (i=0; i< ht->size; ++i) {
61 INIT_HLIST_HEAD(&ht->table[i]);
62 }
63 return 0;
64}
Jerome Glissef2cb5d82009-04-08 17:16:24 +020065EXPORT_SYMBOL(drm_ht_create);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100066
Dave Airliee0be4282007-07-12 10:26:44 +100067void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100068{
Dave Airliee0be4282007-07-12 10:26:44 +100069 struct drm_hash_item *entry;
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100070 struct hlist_head *h_list;
71 struct hlist_node *list;
72 unsigned int hashed_key;
73 int count = 0;
74
75 hashed_key = hash_long(key, ht->order);
76 DRM_DEBUG("Key is 0x%08lx, Hashed key is 0x%08x\n", key, hashed_key);
77 h_list = &ht->table[hashed_key];
78 hlist_for_each(list, h_list) {
Dave Airliee0be4282007-07-12 10:26:44 +100079 entry = hlist_entry(list, struct drm_hash_item, head);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100080 DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key);
81 }
82}
83
Dave Airliebc5f4522007-11-05 12:50:58 +100084static struct hlist_node *drm_ht_find_key(struct drm_open_hash *ht,
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100085 unsigned long key)
86{
Dave Airliee0be4282007-07-12 10:26:44 +100087 struct drm_hash_item *entry;
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100088 struct hlist_head *h_list;
89 struct hlist_node *list;
90 unsigned int hashed_key;
91
92 hashed_key = hash_long(key, ht->order);
93 h_list = &ht->table[hashed_key];
94 hlist_for_each(list, h_list) {
Dave Airliee0be4282007-07-12 10:26:44 +100095 entry = hlist_entry(list, struct drm_hash_item, head);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +100096 if (entry->key == key)
97 return list;
98 if (entry->key > key)
99 break;
100 }
101 return NULL;
102}
103
104
Dave Airliee0be4282007-07-12 10:26:44 +1000105int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000106{
Dave Airliee0be4282007-07-12 10:26:44 +1000107 struct drm_hash_item *entry;
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000108 struct hlist_head *h_list;
109 struct hlist_node *list, *parent;
110 unsigned int hashed_key;
111 unsigned long key = item->key;
112
113 hashed_key = hash_long(key, ht->order);
114 h_list = &ht->table[hashed_key];
115 parent = NULL;
116 hlist_for_each(list, h_list) {
Dave Airliee0be4282007-07-12 10:26:44 +1000117 entry = hlist_entry(list, struct drm_hash_item, head);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000118 if (entry->key == key)
Thomas Hellstrom47cc1402006-09-22 04:04:18 +1000119 return -EINVAL;
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000120 if (entry->key > key)
121 break;
122 parent = list;
123 }
124 if (parent) {
125 hlist_add_after(parent, &item->head);
126 } else {
127 hlist_add_head(&item->head, h_list);
128 }
129 return 0;
130}
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800131EXPORT_SYMBOL(drm_ht_insert_item);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000132
133/*
Dave Airliebc5f4522007-11-05 12:50:58 +1000134 * Just insert an item and return any "bits" bit key that hasn't been
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000135 * used before.
136 */
Dave Airliee0be4282007-07-12 10:26:44 +1000137int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item,
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000138 unsigned long seed, int bits, int shift,
139 unsigned long add)
140{
141 int ret;
142 unsigned long mask = (1 << bits) - 1;
143 unsigned long first, unshifted_key;
144
145 unshifted_key = hash_long(seed, bits);
146 first = unshifted_key;
147 do {
148 item->key = (unshifted_key << shift) + add;
149 ret = drm_ht_insert_item(ht, item);
150 if (ret)
151 unshifted_key = (unshifted_key + 1) & mask;
152 } while(ret && (unshifted_key != first));
153
154 if (ret) {
155 DRM_ERROR("Available key bit space exhausted\n");
156 return -EINVAL;
157 }
158 return 0;
159}
Jerome Glissef2cb5d82009-04-08 17:16:24 +0200160EXPORT_SYMBOL(drm_ht_just_insert_please);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000161
Dave Airliee0be4282007-07-12 10:26:44 +1000162int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key,
163 struct drm_hash_item **item)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000164{
165 struct hlist_node *list;
166
167 list = drm_ht_find_key(ht, key);
168 if (!list)
Thomas Hellstrom47cc1402006-09-22 04:04:18 +1000169 return -EINVAL;
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000170
Dave Airliee0be4282007-07-12 10:26:44 +1000171 *item = hlist_entry(list, struct drm_hash_item, head);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000172 return 0;
173}
Jerome Glissef2cb5d82009-04-08 17:16:24 +0200174EXPORT_SYMBOL(drm_ht_find_item);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000175
Dave Airliee0be4282007-07-12 10:26:44 +1000176int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000177{
178 struct hlist_node *list;
179
180 list = drm_ht_find_key(ht, key);
181 if (list) {
182 hlist_del_init(list);
183 ht->fill--;
184 return 0;
185 }
Thomas Hellstrom47cc1402006-09-22 04:04:18 +1000186 return -EINVAL;
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000187}
188
Dave Airliee0be4282007-07-12 10:26:44 +1000189int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000190{
191 hlist_del_init(&item->head);
192 ht->fill--;
193 return 0;
194}
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800195EXPORT_SYMBOL(drm_ht_remove_item);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000196
Dave Airliee0be4282007-07-12 10:26:44 +1000197void drm_ht_remove(struct drm_open_hash *ht)
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000198{
199 if (ht->table) {
Dave Airliecd839d02007-02-18 17:14:09 +1100200 if (ht->use_vmalloc)
201 vfree(ht->table);
202 else
203 drm_free(ht->table, ht->size * sizeof(*ht->table),
204 DRM_MEM_HASHTAB);
Thomas Hellstrom3a1bd922006-08-07 21:30:28 +1000205 ht->table = NULL;
206 }
207}
Jerome Glissef2cb5d82009-04-08 17:16:24 +0200208EXPORT_SYMBOL(drm_ht_remove);