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Diffstat (limited to 'drivers/staging/batman-adv/hash.h')
-rw-r--r--drivers/staging/batman-adv/hash.h175
1 files changed, 68 insertions, 107 deletions
diff --git a/drivers/staging/batman-adv/hash.h b/drivers/staging/batman-adv/hash.h
index a8e4dd1ec6a0..0b61c6e3e7cf 100644
--- a/drivers/staging/batman-adv/hash.h
+++ b/drivers/staging/batman-adv/hash.h
@@ -22,10 +22,11 @@
#ifndef _NET_BATMAN_ADV_HASH_H_
#define _NET_BATMAN_ADV_HASH_H_
+#include <linux/list.h>
+
#define HASHIT(name) struct hash_it_t name = { \
- .index = -1, .bucket = NULL, \
- .prev_bucket = NULL, \
- .first_bucket = NULL }
+ .index = 0, .walk = NULL, \
+ .safe = NULL}
/* callback to a compare function. should
* compare 2 element datas for their keys,
@@ -41,18 +42,17 @@ typedef void (*hashdata_free_cb)(void *, void *);
struct element_t {
void *data; /* pointer to the data */
- struct element_t *next; /* overflow bucket pointer */
+ struct hlist_node hlist; /* bucket list pointer */
};
struct hash_it_t {
- int index;
- struct element_t *bucket;
- struct element_t *prev_bucket;
- struct element_t **first_bucket;
+ size_t index;
+ struct hlist_node *walk;
+ struct hlist_node *safe;
};
struct hashtable_t {
- struct element_t **table; /* the hashtable itself, with the buckets */
+ struct hlist_head *table; /* the hashtable itself, with the buckets */
int elements; /* number of elements registered */
int size; /* size of hashtable */
};
@@ -75,19 +75,21 @@ void hash_destroy(struct hashtable_t *hash);
static inline void hash_delete(struct hashtable_t *hash,
hashdata_free_cb free_cb, void *arg)
{
- struct element_t *bucket, *last_bucket;
+ struct hlist_head *head;
+ struct hlist_node *walk, *safe;
+ struct element_t *bucket;
int i;
for (i = 0; i < hash->size; i++) {
- bucket = hash->table[i];
+ head = &hash->table[i];
- while (bucket != NULL) {
+ hlist_for_each_safe(walk, safe, head) {
+ bucket = hlist_entry(walk, struct element_t, hlist);
if (free_cb != NULL)
free_cb(bucket->data, arg);
- last_bucket = bucket;
- bucket = bucket->next;
- kfree(last_bucket);
+ hlist_del(walk);
+ kfree(bucket);
}
}
@@ -100,36 +102,30 @@ static inline int hash_add(struct hashtable_t *hash,
hashdata_choose_cb choose, void *data)
{
int index;
- struct element_t *bucket, *prev_bucket = NULL;
+ struct hlist_head *head;
+ struct hlist_node *walk, *safe;
+ struct element_t *bucket;
if (!hash)
return -1;
index = choose(data, hash->size);
- bucket = hash->table[index];
+ head = &hash->table[index];
- while (bucket != NULL) {
+ hlist_for_each_safe(walk, safe, head) {
+ bucket = hlist_entry(walk, struct element_t, hlist);
if (compare(bucket->data, data))
return -1;
-
- prev_bucket = bucket;
- bucket = bucket->next;
}
- /* found the tail of the list, add new element */
+ /* no duplicate found in list, add new element */
bucket = kmalloc(sizeof(struct element_t), GFP_ATOMIC);
if (bucket == NULL)
return -1;
bucket->data = data;
- bucket->next = NULL;
-
- /* and link it */
- if (prev_bucket == NULL)
- hash->table[index] = bucket;
- else
- prev_bucket->next = bucket;
+ hlist_add_head(&bucket->hlist, head);
hash->elements++;
return 0;
@@ -144,22 +140,16 @@ static inline void *hash_remove(struct hashtable_t *hash,
hashdata_choose_cb choose, void *data)
{
struct hash_it_t hash_it_t;
+ struct element_t *bucket;
+ struct hlist_head *head;
hash_it_t.index = choose(data, hash->size);
- hash_it_t.bucket = hash->table[hash_it_t.index];
- hash_it_t.prev_bucket = NULL;
-
- while (hash_it_t.bucket != NULL) {
- if (compare(hash_it_t.bucket->data, data)) {
- hash_it_t.first_bucket =
- (hash_it_t.bucket ==
- hash->table[hash_it_t.index] ?
- &hash->table[hash_it_t.index] : NULL);
- return hash_remove_bucket(hash, &hash_it_t);
- }
+ head = &hash->table[hash_it_t.index];
- hash_it_t.prev_bucket = hash_it_t.bucket;
- hash_it_t.bucket = hash_it_t.bucket->next;
+ hlist_for_each(hash_it_t.walk, head) {
+ bucket = hlist_entry(hash_it_t.walk, struct element_t, hlist);
+ if (compare(bucket->data, data))
+ return hash_remove_bucket(hash, &hash_it_t);
}
return NULL;
@@ -172,19 +162,20 @@ static inline void *hash_find(struct hashtable_t *hash,
hashdata_choose_cb choose, void *keydata)
{
int index;
+ struct hlist_head *head;
+ struct hlist_node *walk;
struct element_t *bucket;
if (!hash)
return NULL;
index = choose(keydata , hash->size);
- bucket = hash->table[index];
+ head = &hash->table[index];
- while (bucket != NULL) {
+ hlist_for_each(walk, head) {
+ bucket = hlist_entry(walk, struct element_t, hlist);
if (compare(bucket->data, keydata))
return bucket->data;
-
- bucket = bucket->next;
}
return NULL;
@@ -193,13 +184,14 @@ static inline void *hash_find(struct hashtable_t *hash,
/* resize the hash, returns the pointer to the new hash or NULL on
* error. removes the old hash on success */
static inline struct hashtable_t *hash_resize(struct hashtable_t *hash,
- hashdata_compare_cb compare,
hashdata_choose_cb choose,
int size)
{
struct hashtable_t *new_hash;
+ struct hlist_head *head, *new_head;
+ struct hlist_node *walk, *safe;
struct element_t *bucket;
- int i;
+ int i, new_index;
/* initialize a new hash with the new size */
new_hash = hash_new(size);
@@ -209,17 +201,20 @@ static inline struct hashtable_t *hash_resize(struct hashtable_t *hash,
/* copy the elements */
for (i = 0; i < hash->size; i++) {
- bucket = hash->table[i];
+ head = &hash->table[i];
+
+ hlist_for_each_safe(walk, safe, head) {
+ bucket = hlist_entry(walk, struct element_t, hlist);
- while (bucket != NULL) {
- hash_add(new_hash, compare, choose, bucket->data);
- bucket = bucket->next;
+ new_index = choose(bucket->data, size);
+ new_head = &new_hash->table[new_index];
+
+ hlist_del(walk);
+ hlist_add_head(walk, new_head);
}
}
- /* remove hash and eventual overflow buckets but not the content
- * itself. */
- hash_delete(hash, NULL, NULL);
+ hash_destroy(hash);
return new_hash;
}
@@ -236,63 +231,29 @@ static inline struct hash_it_t *hash_iterate(struct hashtable_t *hash,
if (!iter)
return NULL;
- /* sanity checks first (if our bucket got deleted in the last
- * iteration): */
- if (iter->bucket != NULL) {
- if (iter->first_bucket != NULL) {
- /* we're on the first element and it got removed after
- * the last iteration. */
- if ((*iter->first_bucket) != iter->bucket) {
- /* there are still other elements in the list */
- if ((*iter->first_bucket) != NULL) {
- iter->prev_bucket = NULL;
- iter->bucket = (*iter->first_bucket);
- iter->first_bucket =
- &hash->table[iter->index];
- return iter;
- } else {
- iter->bucket = NULL;
- }
- }
- } else if (iter->prev_bucket != NULL) {
- /*
- * we're not on the first element, and the bucket got
- * removed after the last iteration. the last bucket's
- * next pointer is not pointing to our actual bucket
- * anymore. select the next.
- */
- if (iter->prev_bucket->next != iter->bucket)
- iter->bucket = iter->prev_bucket;
- }
- }
+ iter->walk = iter->safe;
- /* now as we are sane, select the next one if there is some */
- if (iter->bucket != NULL) {
- if (iter->bucket->next != NULL) {
- iter->prev_bucket = iter->bucket;
- iter->bucket = iter->bucket->next;
- iter->first_bucket = NULL;
- return iter;
- }
- }
+ /* we search for the next head with list entries */
+ if (!iter->walk) {
+ while (iter->index < hash->size) {
+ if (hlist_empty(&hash->table[iter->index]))
+ iter->index++;
+ else {
+ iter->walk = hash->table[iter->index].first;
- /* if not returned yet, we've reached the last one on the index and have
- * to search forward */
- iter->index++;
- /* go through the entries of the hash table */
- while (iter->index < hash->size) {
- if ((hash->table[iter->index]) != NULL) {
- iter->prev_bucket = NULL;
- iter->bucket = hash->table[iter->index];
- iter->first_bucket = &hash->table[iter->index];
- return iter;
- } else {
- iter->index++;
+ /* search next time */
+ ++iter->index;
+ break;
+ }
}
}
- /* nothing to iterate over anymore */
- return NULL;
+ /* return iter when we found bucket otherwise null */
+ if (!iter->walk)
+ return NULL;
+
+ iter->safe = iter->walk->next;
+ return iter;
}
#endif /* _NET_BATMAN_ADV_HASH_H_ */
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-15 23:29:29 +0000