net: selftests: export packet creation helpers for driver use

Export the network selftest packet creation infrastructure to allow
network drivers to reuse the existing selftest framework instead of
duplicating packet creation code.

Signed-off-by: Raju Rangoju <[e-mail]>
Reviewed-by: Maxime Chevallier <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Paolo Abeni <[e-mail]>

include/net/selftests.h

···
 #define _NET_SELFTESTS
 
 #include <linux/ethtool.h>
+#include <linux/netdevice.h>
+
+struct net_packet_attrs {
+	const unsigned char *src;
+	const unsigned char *dst;
+	u32 ip_src;
+	u32 ip_dst;
+	bool tcp;
+	u16 sport;
+	u16 dport;
+	int timeout;
+	int size;
+	int max_size;
+	u8 id;
+	u16 queue_mapping;
+	bool bad_csum;
+};
+
+struct net_test_priv {
+	struct net_packet_attrs *packet;
+	struct packet_type pt;
+	struct completion comp;
+	int double_vlan;
+	int vlan_id;
+	int ok;
+};
+
+struct netsfhdr {
+	__be32 version;
+	__be64 magic;
+	u8 id;
+} __packed;
+
+#define NET_TEST_PKT_SIZE (sizeof(struct ethhdr) + sizeof(struct iphdr) + \
+			   sizeof(struct netsfhdr))
+#define NET_TEST_PKT_MAGIC	0xdeadcafecafedeadULL
+#define NET_LB_TIMEOUT		msecs_to_jiffies(200)
 
 #if IS_ENABLED(CONFIG_NET_SELFTESTS)
 
+struct sk_buff *net_test_get_skb(struct net_device *ndev, u8 id,
+				 struct net_packet_attrs *attr);
 void net_selftest(struct net_device *ndev, struct ethtool_test *etest,
 		  u64 *buf);
 int net_selftest_get_count(void);
 void net_selftest_get_strings(u8 *data);
 
 #else
+
+static inline struct sk_buff *net_test_get_skb(struct net_device *ndev, u8 id,
+					       struct net_packet_attrs *attr)
+{
+	return NULL;
+}
 
 static inline void net_selftest(struct net_device *ndev, struct ethtool_test *etest,
 				u64 *buf)

net/core/selftests.c

···
 #include <net/tcp.h>
 #include <net/udp.h>
 
-struct net_packet_attrs {
-	const unsigned char *src;
-	const unsigned char *dst;
-	u32 ip_src;
-	u32 ip_dst;
-	bool tcp;
-	u16 sport;
-	u16 dport;
-	int timeout;
-	int size;
-	int max_size;
-	u8 id;
-	u16 queue_mapping;
-	bool bad_csum;
-};
-
-struct net_test_priv {
-	struct net_packet_attrs *packet;
-	struct packet_type pt;
-	struct completion comp;
-	int double_vlan;
-	int vlan_id;
-	int ok;
-};
-
-struct netsfhdr {
-	__be32 version;
-	__be64 magic;
-	u8 id;
-} __packed;
-
 static u8 net_test_next_id;
 
-#define NET_TEST_PKT_SIZE (sizeof(struct ethhdr) + sizeof(struct iphdr) + \
-			   sizeof(struct netsfhdr))
-#define NET_TEST_PKT_MAGIC	0xdeadcafecafedeadULL
-#define NET_LB_TIMEOUT		msecs_to_jiffies(200)
-
-static struct sk_buff *net_test_get_skb(struct net_device *ndev,
-					struct net_packet_attrs *attr)
+struct sk_buff *net_test_get_skb(struct net_device *ndev, u8 id,
+				 struct net_packet_attrs *attr)
 {
 	struct sk_buff *skb = NULL;
 	struct udphdr *uhdr = NULL;
···
 	shdr = skb_put(skb, sizeof(*shdr));
 	shdr->version = 0;
 	shdr->magic = cpu_to_be64(NET_TEST_PKT_MAGIC);
-	attr->id = net_test_next_id;
-	shdr->id = net_test_next_id++;
+	attr->id = id;
+	shdr->id = id;
 
 	if (attr->size) {
 		void *payload = skb_put(skb, attr->size);
···
 
 	return skb;
 }
+EXPORT_SYMBOL_GPL(net_test_get_skb);
 
 static int net_test_loopback_validate(struct sk_buff *skb,
 				      struct net_device *ndev,
···
 	tpriv->packet = attr;
 	dev_add_pack(&tpriv->pt);
 
-	skb = net_test_get_skb(ndev, attr);
+	skb = net_test_get_skb(ndev, net_test_next_id, attr);
 	if (!skb) {
 		ret = -ENOMEM;
 		goto cleanup;
 	}
 
+	net_test_next_id++;
 	ret = dev_direct_xmit(skb, attr->queue_mapping);
 	if (ret < 0) {
 		goto cleanup;