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![Ken Helias](/assets/img/avatar_default.png)
All other add functions for lists have the new item as first argument and the position where it is added as second argument. This was changed for no good reason in this function and makes using it unnecessary confusing. The name was changed to hlist_add_behind() to cause unconverted code to generate a compile error instead of using the wrong parameter order. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Ken Helias <kenhelias@firemail.de> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [intel driver bits] Cc: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
208 lines
5.4 KiB
C
208 lines
5.4 KiB
C
/**************************************************************************
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*
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* Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND. USA.
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* All Rights Reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sub license, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice (including the
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* next paragraph) shall be included in all copies or substantial portions
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* of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
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* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
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* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
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* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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* USE OR OTHER DEALINGS IN THE SOFTWARE.
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*
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*
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**************************************************************************/
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/*
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* Simple open hash tab implementation.
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*
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* Authors:
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* Thomas Hellström <thomas-at-tungstengraphics-dot-com>
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*/
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#include <drm/drmP.h>
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#include <drm/drm_hashtab.h>
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#include <linux/hash.h>
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#include <linux/slab.h>
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#include <linux/export.h>
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int drm_ht_create(struct drm_open_hash *ht, unsigned int order)
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{
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unsigned int size = 1 << order;
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ht->order = order;
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ht->table = NULL;
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if (size <= PAGE_SIZE / sizeof(*ht->table))
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ht->table = kcalloc(size, sizeof(*ht->table), GFP_KERNEL);
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else
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ht->table = vzalloc(size*sizeof(*ht->table));
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if (!ht->table) {
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DRM_ERROR("Out of memory for hash table\n");
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return -ENOMEM;
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}
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return 0;
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}
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EXPORT_SYMBOL(drm_ht_create);
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void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key)
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{
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struct drm_hash_item *entry;
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struct hlist_head *h_list;
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unsigned int hashed_key;
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int count = 0;
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hashed_key = hash_long(key, ht->order);
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DRM_DEBUG("Key is 0x%08lx, Hashed key is 0x%08x\n", key, hashed_key);
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h_list = &ht->table[hashed_key];
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hlist_for_each_entry(entry, h_list, head)
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DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key);
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}
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static struct hlist_node *drm_ht_find_key(struct drm_open_hash *ht,
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unsigned long key)
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{
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struct drm_hash_item *entry;
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struct hlist_head *h_list;
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unsigned int hashed_key;
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hashed_key = hash_long(key, ht->order);
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h_list = &ht->table[hashed_key];
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hlist_for_each_entry(entry, h_list, head) {
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if (entry->key == key)
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return &entry->head;
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if (entry->key > key)
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break;
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}
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return NULL;
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}
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static struct hlist_node *drm_ht_find_key_rcu(struct drm_open_hash *ht,
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unsigned long key)
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{
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struct drm_hash_item *entry;
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struct hlist_head *h_list;
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unsigned int hashed_key;
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hashed_key = hash_long(key, ht->order);
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h_list = &ht->table[hashed_key];
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hlist_for_each_entry_rcu(entry, h_list, head) {
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if (entry->key == key)
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return &entry->head;
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if (entry->key > key)
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break;
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}
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return NULL;
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}
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int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item)
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{
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struct drm_hash_item *entry;
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struct hlist_head *h_list;
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struct hlist_node *parent;
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unsigned int hashed_key;
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unsigned long key = item->key;
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hashed_key = hash_long(key, ht->order);
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h_list = &ht->table[hashed_key];
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parent = NULL;
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hlist_for_each_entry(entry, h_list, head) {
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if (entry->key == key)
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return -EINVAL;
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if (entry->key > key)
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break;
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parent = &entry->head;
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}
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if (parent) {
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hlist_add_behind_rcu(&item->head, parent);
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} else {
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hlist_add_head_rcu(&item->head, h_list);
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}
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return 0;
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}
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EXPORT_SYMBOL(drm_ht_insert_item);
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/*
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* Just insert an item and return any "bits" bit key that hasn't been
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* used before.
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*/
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int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *item,
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unsigned long seed, int bits, int shift,
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unsigned long add)
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{
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int ret;
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unsigned long mask = (1 << bits) - 1;
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unsigned long first, unshifted_key;
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unshifted_key = hash_long(seed, bits);
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first = unshifted_key;
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do {
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item->key = (unshifted_key << shift) + add;
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ret = drm_ht_insert_item(ht, item);
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if (ret)
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unshifted_key = (unshifted_key + 1) & mask;
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} while(ret && (unshifted_key != first));
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if (ret) {
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DRM_ERROR("Available key bit space exhausted\n");
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return -EINVAL;
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}
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return 0;
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}
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EXPORT_SYMBOL(drm_ht_just_insert_please);
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int drm_ht_find_item(struct drm_open_hash *ht, unsigned long key,
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struct drm_hash_item **item)
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{
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struct hlist_node *list;
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list = drm_ht_find_key_rcu(ht, key);
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if (!list)
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return -EINVAL;
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*item = hlist_entry(list, struct drm_hash_item, head);
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return 0;
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}
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EXPORT_SYMBOL(drm_ht_find_item);
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int drm_ht_remove_key(struct drm_open_hash *ht, unsigned long key)
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{
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struct hlist_node *list;
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list = drm_ht_find_key(ht, key);
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if (list) {
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hlist_del_init_rcu(list);
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return 0;
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}
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return -EINVAL;
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}
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int drm_ht_remove_item(struct drm_open_hash *ht, struct drm_hash_item *item)
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{
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hlist_del_init_rcu(&item->head);
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return 0;
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}
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EXPORT_SYMBOL(drm_ht_remove_item);
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void drm_ht_remove(struct drm_open_hash *ht)
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{
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if (ht->table) {
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if ((PAGE_SIZE / sizeof(*ht->table)) >> ht->order)
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kfree(ht->table);
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else
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vfree(ht->table);
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ht->table = NULL;
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}
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}
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EXPORT_SYMBOL(drm_ht_remove);
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