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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#include <linux/slab.h>
39
40int drm_ht_create(struct drm_open_hash *ht, unsigned int order)
41{
42 unsigned int size = 1 << order;
43
44 ht->order = order;
45 ht->table = NULL;
46 if (size <= PAGE_SIZE / sizeof(*ht->table))
47 ht->table = kcalloc(size, sizeof(*ht->table), GFP_KERNEL);
48 else
49 ht->table = vzalloc(size*sizeof(*ht->table));
50 if (!ht->table) {
51 DRM_ERROR("Out of memory for hash table\n");
52 return -ENOMEM;
53 }
54 return 0;
55}
56EXPORT_SYMBOL(drm_ht_create);
57
58void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key)
59{
60 struct drm_hash_item *entry;
61 struct hlist_head *h_list;
62 struct hlist_node *list;
63 unsigned int hashed_key;
64 int count = 0;
65
66 hashed_key = hash_long(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];
69 hlist_for_each(list, h_list) {
70 entry = hlist_entry(list, struct drm_hash_item, head);
71 DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key);
72 }
73}
74
75static struct hlist_node *drm_ht_find_key(struct drm_open_hash *ht,
76 unsigned long key)
77{
78 struct drm_hash_item *entry;
79 struct hlist_head *h_list;
80 struct hlist_node *list;
81 unsigned int hashed_key;
82
83 hashed_key = hash_long(key, ht->order);
84 h_list = &ht->table[hashed_key];
85 hlist_for_each(list, h_list) {
86 entry = hlist_entry(list, struct drm_hash_item, head);
87 if (entry->key == key)
88 return list;
89 if (entry->key > key)
90 break;
91 }
92 return NULL;
93}
94
95
96int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item)
97{
98 struct drm_hash_item *entry;
99 struct hlist_head *h_list;
100 struct hlist_node *list, *parent;
101 unsigned int hashed_key;
102 unsigned long key = item->key;
103
104 hashed_key = hash_long(key, ht->order);
105 h_list = &ht->table[hashed_key];
106 parent = NULL;
107 hlist_for_each(list, h_list) {
108 entry = hlist_entry(list, struct drm_hash_item, head);
109 if (entry->key == key)
110 return -EINVAL;
111 if (entry->key > key)
112 break;
113 parent = list;
114 }
115 if (parent) {
116 hlist_add_after(parent, &item->head);
117 } else {
118 hlist_add_head(&item->head, h_list);
119 }
120 return 0;
121}
122EXPORT_SYMBOL(drm_ht_insert_item);
123
124/*
125 * Just insert an item and return any "bits" bit key that hasn't been
126 * used before.
127 */
128int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item,
129 unsigned long seed, int bits, int shift,
130 unsigned long add)
131{
132 int ret;
133 unsigned long mask = (1 << bits) - 1;
134 unsigned long first, unshifted_key;
135
136 unshifted_key = hash_long(seed, bits);
137 first = unshifted_key;
138 do {
139 item->key = (unshifted_key << shift) + add;
140 ret = drm_ht_insert_item(ht, item);
141 if (ret)
142 unshifted_key = (unshifted_key + 1) & mask;
143 } while(ret && (unshifted_key != first));
144
145 if (ret) {
146 DRM_ERROR("Available key bit space exhausted\n");
147 return -EINVAL;
148 }
149 return 0;
150}
151EXPORT_SYMBOL(drm_ht_just_insert_please);
152
153int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key,
154 struct drm_hash_item **item)
155{
156 struct hlist_node *list;
157
158 list = drm_ht_find_key(ht, key);
159 if (!list)
160 return -EINVAL;
161
162 *item = hlist_entry(list, struct drm_hash_item, head);
163 return 0;
164}
165EXPORT_SYMBOL(drm_ht_find_item);
166
167int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key)
168{
169 struct hlist_node *list;
170
171 list = drm_ht_find_key(ht, key);
172 if (list) {
173 hlist_del_init(list);
174 return 0;
175 }
176 return -EINVAL;
177}
178
179int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item)
180{
181 hlist_del_init(&item->head);
182 return 0;
183}
184EXPORT_SYMBOL(drm_ht_remove_item);
185
186void drm_ht_remove(struct drm_open_hash *ht)
187{
188 if (ht->table) {
189 if ((PAGE_SIZE / sizeof(*ht->table)) >> ht->order)
190 kfree(ht->table);
191 else
192 vfree(ht->table);
193 ht->table = NULL;
194 }
195}
196EXPORT_SYMBOL(drm_ht_remove);
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 <linux/hash.h>
36#include <linux/mm.h>
37#include <linux/rculist.h>
38#include <linux/slab.h>
39#include <linux/vmalloc.h>
40
41#include <drm/drm_print.h>
42
43#include "drm_legacy.h"
44
45int drm_ht_create(struct drm_open_hash *ht, unsigned int order)
46{
47 unsigned int size = 1 << order;
48
49 ht->order = order;
50 ht->table = NULL;
51 if (size <= PAGE_SIZE / sizeof(*ht->table))
52 ht->table = kcalloc(size, sizeof(*ht->table), GFP_KERNEL);
53 else
54 ht->table = vzalloc(array_size(size, sizeof(*ht->table)));
55 if (!ht->table) {
56 DRM_ERROR("Out of memory for hash table\n");
57 return -ENOMEM;
58 }
59 return 0;
60}
61
62void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key)
63{
64 struct drm_hash_item *entry;
65 struct hlist_head *h_list;
66 unsigned int hashed_key;
67 int count = 0;
68
69 hashed_key = hash_long(key, ht->order);
70 DRM_DEBUG("Key is 0x%08lx, Hashed key is 0x%08x\n", key, hashed_key);
71 h_list = &ht->table[hashed_key];
72 hlist_for_each_entry(entry, h_list, head)
73 DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key);
74}
75
76static struct hlist_node *drm_ht_find_key(struct drm_open_hash *ht,
77 unsigned long key)
78{
79 struct drm_hash_item *entry;
80 struct hlist_head *h_list;
81 unsigned int hashed_key;
82
83 hashed_key = hash_long(key, ht->order);
84 h_list = &ht->table[hashed_key];
85 hlist_for_each_entry(entry, h_list, head) {
86 if (entry->key == key)
87 return &entry->head;
88 if (entry->key > key)
89 break;
90 }
91 return NULL;
92}
93
94static struct hlist_node *drm_ht_find_key_rcu(struct drm_open_hash *ht,
95 unsigned long key)
96{
97 struct drm_hash_item *entry;
98 struct hlist_head *h_list;
99 unsigned int hashed_key;
100
101 hashed_key = hash_long(key, ht->order);
102 h_list = &ht->table[hashed_key];
103 hlist_for_each_entry_rcu(entry, h_list, head) {
104 if (entry->key == key)
105 return &entry->head;
106 if (entry->key > key)
107 break;
108 }
109 return NULL;
110}
111
112int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item)
113{
114 struct drm_hash_item *entry;
115 struct hlist_head *h_list;
116 struct hlist_node *parent;
117 unsigned int hashed_key;
118 unsigned long key = item->key;
119
120 hashed_key = hash_long(key, ht->order);
121 h_list = &ht->table[hashed_key];
122 parent = NULL;
123 hlist_for_each_entry(entry, h_list, head) {
124 if (entry->key == key)
125 return -EINVAL;
126 if (entry->key > key)
127 break;
128 parent = &entry->head;
129 }
130 if (parent) {
131 hlist_add_behind_rcu(&item->head, parent);
132 } else {
133 hlist_add_head_rcu(&item->head, h_list);
134 }
135 return 0;
136}
137
138/*
139 * Just insert an item and return any "bits" bit key that hasn't been
140 * used before.
141 */
142int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item,
143 unsigned long seed, int bits, int shift,
144 unsigned long add)
145{
146 int ret;
147 unsigned long mask = (1UL << bits) - 1;
148 unsigned long first, unshifted_key;
149
150 unshifted_key = hash_long(seed, bits);
151 first = unshifted_key;
152 do {
153 item->key = (unshifted_key << shift) + add;
154 ret = drm_ht_insert_item(ht, item);
155 if (ret)
156 unshifted_key = (unshifted_key + 1) & mask;
157 } while(ret && (unshifted_key != first));
158
159 if (ret) {
160 DRM_ERROR("Available key bit space exhausted\n");
161 return -EINVAL;
162 }
163 return 0;
164}
165
166int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key,
167 struct drm_hash_item **item)
168{
169 struct hlist_node *list;
170
171 list = drm_ht_find_key_rcu(ht, key);
172 if (!list)
173 return -EINVAL;
174
175 *item = hlist_entry(list, struct drm_hash_item, head);
176 return 0;
177}
178
179int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key)
180{
181 struct hlist_node *list;
182
183 list = drm_ht_find_key(ht, key);
184 if (list) {
185 hlist_del_init_rcu(list);
186 return 0;
187 }
188 return -EINVAL;
189}
190
191int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item)
192{
193 hlist_del_init_rcu(&item->head);
194 return 0;
195}
196
197void drm_ht_remove(struct drm_open_hash *ht)
198{
199 if (ht->table) {
200 kvfree(ht->table);
201 ht->table = NULL;
202 }
203}