xdp: Remove the functions xsk_map_inc and xsk_map_put

The functions xsk_map_put() and xsk_map_inc() are simple wrappers and
as such, replace these functions with the functions bpf_map_inc() and
bpf_map_put() and remove some error testing code.

Signed-off-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/1606402998-12562-1-git-send-email-yanjunz@nvidia.com

Author: Zhu Yanjun

net/xdp/xsk.c

@@ -605,7 +605,7 @@ static struct xsk_map *xsk_get_map_list_entry(struct xdp_sock *xs,
 	node = list_first_entry_or_null(&xs->map_list, struct xsk_map_node,
 					node);
 	if (node) {
-		WARN_ON(xsk_map_inc(node->map));
+		bpf_map_inc(&node->map->map);
 		map = node->map;
 		*map_entry = node->map_entry;
 	}
@@ -635,7 +635,7 @@ static void xsk_delete_from_maps(struct xdp_sock *xs)
 
 	while ((map = xsk_get_map_list_entry(xs, &map_entry))) {
 		xsk_map_try_sock_delete(map, xs, map_entry);
-		xsk_map_put(map);
+		bpf_map_put(&map->map);
 	}
 }
 

net/xdp/xsk.h

@@ -41,8 +41,6 @@ static inline struct xdp_sock *xdp_sk(struct sock *sk)
 
 void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
 			     struct xdp_sock **map_entry);
-int xsk_map_inc(struct xsk_map *map);
-void xsk_map_put(struct xsk_map *map);
 void xsk_clear_pool_at_qid(struct net_device *dev, u16 queue_id);
 int xsk_reg_pool_at_qid(struct net_device *dev, struct xsk_buff_pool *pool,
 			u16 queue_id);

net/xdp/xskmap.c

@@ -11,32 +11,16 @@
 
 #include "xsk.h"
 
-int xsk_map_inc(struct xsk_map *map)
-{
-	bpf_map_inc(&map->map);
-	return 0;
-}
-
-void xsk_map_put(struct xsk_map *map)
-{
-	bpf_map_put(&map->map);
-}
-
 static struct xsk_map_node *xsk_map_node_alloc(struct xsk_map *map,
 					       struct xdp_sock **map_entry)
 {
 	struct xsk_map_node *node;
-	int err;
 
 	node = kzalloc(sizeof(*node), GFP_ATOMIC | __GFP_NOWARN);
 	if (!node)
 		return ERR_PTR(-ENOMEM);
 
-	err = xsk_map_inc(map);
-	if (err) {
-		kfree(node);
-		return ERR_PTR(err);
-	}
+	bpf_map_inc(&map->map);
 
 	node->map = map;
 	node->map_entry = map_entry;
@@ -45,7 +29,7 @@ static struct xsk_map_node *xsk_map_node_alloc(struct xsk_map *map,
 
 static void xsk_map_node_free(struct xsk_map_node *node)
 {
-	xsk_map_put(node->map);
+	bpf_map_put(&node->map->map);
 	kfree(node);
 }