neighbour: use kvzalloc()/kvfree()

mm layer is providing convenient functions, we do not have
to work around old limitations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Gilad Naaman <gnaaman@drivenets.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241022150059.1345406-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: edumazet

net/core/neighbour.c

@@ -14,7 +14,6 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/slab.h>
-#include <linux/kmemleak.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -538,14 +537,7 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
 	ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
 	if (!ret)
 		return NULL;
-	if (size <= PAGE_SIZE) {
-		buckets = kzalloc(size, GFP_ATOMIC);
-	} else {
-		buckets = (struct neighbour __rcu **)
-			  __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
-					   get_order(size));
-		kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
-	}
+	buckets = kvzalloc(size, GFP_ATOMIC);
 	if (!buckets) {
 		kfree(ret);
 		return NULL;
@@ -562,15 +554,8 @@ static void neigh_hash_free_rcu(struct rcu_head *head)
 	struct neigh_hash_table *nht = container_of(head,
 						    struct neigh_hash_table,
 						    rcu);
-	size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
-	struct neighbour __rcu **buckets = nht->hash_buckets;
 
-	if (size <= PAGE_SIZE) {
-		kfree(buckets);
-	} else {
-		kmemleak_free(buckets);
-		free_pages((unsigned long)buckets, get_order(size));
-	}
+	kvfree(nht->hash_buckets);
 	kfree(nht);
 }