1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2006-2019 B.A.T.M.A.N. contributors:
3 *
4 * Simon Wunderlich, Marek Lindner
5 */
6
7 #include "hash.h"
8 #include "main.h"
9
10 #include <linux/gfp.h>
11 #include <linux/lockdep.h>
12 #include <linux/slab.h>
13
14 /* clears the hash */
batadv_hash_init(struct batadv_hashtable * hash)15 static void batadv_hash_init(struct batadv_hashtable *hash)
16 {
17 u32 i;
18
19 for (i = 0; i < hash->size; i++) {
20 INIT_HLIST_HEAD(&hash->table[i]);
21 spin_lock_init(&hash->list_locks[i]);
22 }
23
24 atomic_set(&hash->generation, 0);
25 }
26
27 /**
28 * batadv_hash_destroy() - Free only the hashtable and the hash itself
29 * @hash: hash object to destroy
30 */
batadv_hash_destroy(struct batadv_hashtable * hash)31 void batadv_hash_destroy(struct batadv_hashtable *hash)
32 {
33 kfree(hash->list_locks);
34 kfree(hash->table);
35 kfree(hash);
36 }
37
38 /**
39 * batadv_hash_new() - Allocates and clears the hashtable
40 * @size: number of hash buckets to allocate
41 *
42 * Return: newly allocated hashtable, NULL on errors
43 */
batadv_hash_new(u32 size)44 struct batadv_hashtable *batadv_hash_new(u32 size)
45 {
46 struct batadv_hashtable *hash;
47
48 hash = kmalloc(sizeof(*hash), GFP_ATOMIC);
49 if (!hash)
50 return NULL;
51
52 hash->table = kmalloc_array(size, sizeof(*hash->table), GFP_ATOMIC);
53 if (!hash->table)
54 goto free_hash;
55
56 hash->list_locks = kmalloc_array(size, sizeof(*hash->list_locks),
57 GFP_ATOMIC);
58 if (!hash->list_locks)
59 goto free_table;
60
61 hash->size = size;
62 batadv_hash_init(hash);
63 return hash;
64
65 free_table:
66 kfree(hash->table);
67 free_hash:
68 kfree(hash);
69 return NULL;
70 }
71
72 /**
73 * batadv_hash_set_lock_class() - Set specific lockdep class for hash spinlocks
74 * @hash: hash object to modify
75 * @key: lockdep class key address
76 */
batadv_hash_set_lock_class(struct batadv_hashtable * hash,struct lock_class_key * key)77 void batadv_hash_set_lock_class(struct batadv_hashtable *hash,
78 struct lock_class_key *key)
79 {
80 u32 i;
81
82 for (i = 0; i < hash->size; i++)
83 lockdep_set_class(&hash->list_locks[i], key);
84 }
85