net/batman-adv/hash.c

   1 /* Copyright (C) 2006-2015 B.A.T.M.A.N. contributors:
   2  *
   3  * Simon Wunderlich, Marek Lindner
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "hash.h"
  19 #include "main.h"
  20
  21 #include <linux/fs.h>
  22 #include <linux/lockdep.h>
  23 #include <linux/slab.h>
  24
  25 /* clears the hash */
  26 static void batadv_hash_init(struct batadv_hashtable *hash)
  27 {
  28         u32 i;
  29
  30         for (i = 0; i < hash->size; i++) {
  31                 INIT_HLIST_HEAD(&hash->table[i]);
  32                 spin_lock_init(&hash->list_locks[i]);
  33         }
  34 }
  35
  36 /* free only the hashtable and the hash itself. */
  37 void batadv_hash_destroy(struct batadv_hashtable *hash)
  38 {
  39         kfree(hash->list_locks);
  40         kfree(hash->table);
  41         kfree(hash);
  42 }
  43
  44 /* allocates and clears the hash */
  45 struct batadv_hashtable *batadv_hash_new(u32 size)
  46 {
  47         struct batadv_hashtable *hash;
  48
  49         hash = kmalloc(sizeof(*hash), GFP_ATOMIC);
  50         if (!hash)
  51                 return NULL;
  52
  53         hash->table = kmalloc_array(size, sizeof(*hash->table), GFP_ATOMIC);
  54         if (!hash->table)
  55                 goto free_hash;
  56
  57         hash->list_locks = kmalloc_array(size, sizeof(*hash->list_locks),
  58                                          GFP_ATOMIC);
  59         if (!hash->list_locks)
  60                 goto free_table;
  61
  62         hash->size = size;
  63         batadv_hash_init(hash);
  64         return hash;
  65
  66 free_table:
  67         kfree(hash->table);
  68 free_hash:
  69         kfree(hash);
  70         return NULL;
  71 }
  72
  73 void batadv_hash_set_lock_class(struct batadv_hashtable *hash,
  74                                 struct lock_class_key *key)
  75 {
  76         u32 i;
  77
  78         for (i = 0; i < hash->size; i++)
  79                 lockdep_set_class(&hash->list_locks[i], key);
  80 }