+
+struct rhash_head __rcu **rht_bucket_nested(const struct bucket_table *tbl,
+ unsigned int hash)
+{
+ const unsigned int shift = PAGE_SHIFT - ilog2(sizeof(void *));
+ static struct rhash_head __rcu *rhnull =
+ (struct rhash_head __rcu *)NULLS_MARKER(0);
+ unsigned int index = hash & ((1 << tbl->nest) - 1);
+ unsigned int size = tbl->size >> tbl->nest;
+ unsigned int subhash = hash;
+ union nested_table *ntbl;
+
+ ntbl = (union nested_table *)rcu_dereference_raw(tbl->buckets[0]);
+ ntbl = rht_dereference_bucket(ntbl[index].table, tbl, hash);
+ subhash >>= tbl->nest;
+
+ while (ntbl && size > (1 << shift)) {
+ index = subhash & ((1 << shift) - 1);
+ ntbl = rht_dereference_bucket(ntbl[index].table, tbl, hash);
+ size >>= shift;
+ subhash >>= shift;
+ }
+
+ if (!ntbl)
+ return &rhnull;
+
+ return &ntbl[subhash].bucket;
+
+}
+EXPORT_SYMBOL_GPL(rht_bucket_nested);
+
+struct rhash_head __rcu **rht_bucket_nested_insert(struct rhashtable *ht,
+ struct bucket_table *tbl,
+ unsigned int hash)
+{
+ const unsigned int shift = PAGE_SHIFT - ilog2(sizeof(void *));
+ unsigned int index = hash & ((1 << tbl->nest) - 1);
+ unsigned int size = tbl->size >> tbl->nest;
+ union nested_table *ntbl;
+ unsigned int shifted;
+ unsigned int nhash;
+
+ ntbl = (union nested_table *)rcu_dereference_raw(tbl->buckets[0]);
+ hash >>= tbl->nest;
+ nhash = index;
+ shifted = tbl->nest;
+ ntbl = nested_table_alloc(ht, &ntbl[index].table,
+ size <= (1 << shift) ? shifted : 0, nhash);
+
+ while (ntbl && size > (1 << shift)) {
+ index = hash & ((1 << shift) - 1);
+ size >>= shift;
+ hash >>= shift;
+ nhash |= index << shifted;
+ shifted += shift;
+ ntbl = nested_table_alloc(ht, &ntbl[index].table,
+ size <= (1 << shift) ? shifted : 0,
+ nhash);
+ }
+
+ if (!ntbl)
+ return NULL;
+
+ return &ntbl[hash].bucket;
+
+}
+EXPORT_SYMBOL_GPL(rht_bucket_nested_insert);