Initial import

1 files changed, 79 insertions, 0 deletions

diff --git a/include/drm/drm_hashtab.h b/include/drm/drm_hashtab.h
new file mode 100644
index 000000000..fce2ef3fd
--- /dev/null
+++ b/include/drm/drm_hashtab.h
@@ -0,0 +1,79 @@
+/**************************************************************************
+ *
+ * Copyright 2006 Tungsten Graphics, Inc., Bismack, ND. USA.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ *
+ **************************************************************************/
+/*
+ * Simple open hash tab implementation.
+ *
+ * Authors:
+ * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
+ */
+
+#ifndef DRM_HASHTAB_H
+#define DRM_HASHTAB_H
+
+#include <linux/list.h>
+
+#define drm_hash_entry(_ptr, _type, _member) container_of(_ptr, _type, _member)
+
+struct drm_hash_item {
+	struct hlist_node head;
+	unsigned long key;
+};
+
+struct drm_open_hash {
+	struct hlist_head *table;
+	u8 order;
+};
+
+extern int drm_ht_create(struct drm_open_hash *ht, unsigned int order);
+extern int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item);
+extern int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item,
+				     unsigned long seed, int bits, int shift,
+				     unsigned long add);
+extern int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key, struct drm_hash_item **item);
+
+extern void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key);
+extern int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key);
+extern int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item);
+extern void drm_ht_remove(struct drm_open_hash *ht);
+
+/*
+ * RCU-safe interface
+ *
+ * The user of this API needs to make sure that two or more instances of the
+ * hash table manipulation functions are never run simultaneously.
+ * The lookup function drm_ht_find_item_rcu may, however, run simultaneously
+ * with any of the manipulation functions as long as it's called from within
+ * an RCU read-locked section.
+ */
+#define drm_ht_insert_item_rcu drm_ht_insert_item
+#define drm_ht_just_insert_please_rcu drm_ht_just_insert_please
+#define drm_ht_remove_key_rcu drm_ht_remove_key
+#define drm_ht_remove_item_rcu drm_ht_remove_item
+#define drm_ht_find_item_rcu drm_ht_find_item
+
+#endif