bpf: Move a few bpf_local_storage functions to static scope

This patch moves the bpf_local_storage_free_rcu() and
bpf_selem_unlink_map() to static because they are
not used outside of bpf_local_storage.c.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20230308065936.1550103-2-martin.lau@linux.devSigned-off-by: Alexei Starovoitov <ast@kernel.org>

include/linux/bpf_local_storage.h

@@ -147,8 +147,6 @@ void bpf_selem_unlink(struct bpf_local_storage_elem *selem, bool use_trace_rcu);
 void bpf_selem_link_map(struct bpf_local_storage_map *smap,
 			struct bpf_local_storage_elem *selem);
 
-void bpf_selem_unlink_map(struct bpf_local_storage_elem *selem);
-
 struct bpf_local_storage_elem *
 bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner, void *value,
 		bool charge_mem, gfp_t gfp_flags);
@@ -163,7 +161,6 @@ struct bpf_local_storage_data *
 bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
 			 void *value, u64 map_flags, gfp_t gfp_flags);
 
-void bpf_local_storage_free_rcu(struct rcu_head *rcu);
 u64 bpf_local_storage_map_mem_usage(const struct bpf_map *map);
 
 #endif /* _BPF_LOCAL_STORAGE_H */

kernel/bpf/bpf_local_storage.c

@@ -95,7 +95,7 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
 	return NULL;
 }
 
-void bpf_local_storage_free_rcu(struct rcu_head *rcu)
+static void bpf_local_storage_free_rcu(struct rcu_head *rcu)
 {
 	struct bpf_local_storage *local_storage;
 
@@ -251,7 +251,7 @@ void bpf_selem_link_storage_nolock(struct bpf_local_storage *local_storage,
 	hlist_add_head_rcu(&selem->snode, &local_storage->list);
 }
 
-void bpf_selem_unlink_map(struct bpf_local_storage_elem *selem)
+static void bpf_selem_unlink_map(struct bpf_local_storage_elem *selem)
 {
 	struct bpf_local_storage_map *smap;
 	struct bpf_local_storage_map_bucket *b;