[PATCH bpf-next 04/13] bpf: refactor map_get_next_key()

[Yonghong Song]

Refactor function map_get_next_key() with a new helper
bpf_map_get_next_key(), which will be used later
for batched map lookup/lookup_and_delete/delete operations.

Signed-off-by: Yonghong Song <y...@fb.com>
---
 kernel/bpf/syscall.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b8bba499df11..06308f0206e5 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1048,6 +1048,20 @@ static int map_delete_elem(union bpf_attr *attr)
        return err;
 }
 
+static int bpf_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
+{
+       int err;
+
+       if (bpf_map_is_dev_bound(map))
+               return bpf_map_offload_get_next_key(map, key, next_key);
+
+       rcu_read_lock();
+       err = map->ops->map_get_next_key(map, key, next_key);
+       rcu_read_unlock();
+
+       return err;
+}
+
 /* last field in 'union bpf_attr' used by this command */
 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
 
@@ -1088,15 +1102,7 @@ static int map_get_next_key(union bpf_attr *attr)
        if (!next_key)
                goto free_key;
 
-       if (bpf_map_is_dev_bound(map)) {
-               err = bpf_map_offload_get_next_key(map, key, next_key);
-               goto out;
-       }
-
-       rcu_read_lock();
-       err = map->ops->map_get_next_key(map, key, next_key);
-       rcu_read_unlock();
-out:
+       err = bpf_map_get_next_key(map, key, next_key);
        if (err)
                goto free_next_key;
 
-- 
2.17.1