net: gro: rename skb_gro_header_hard()

skb_gro_header_hard() is renamed to skb_gro_may_pull() to match
the convention used by common helpers like pskb_may_pull().

This means the condition is inverted:

	if (skb_gro_header_hard(skb, hlen))
		slow_path();

becomes:

	if (!skb_gro_may_pull(skb, hlen))
		slow_path();
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/geneve.c

@@ -508,7 +508,7 @@ static struct sk_buff *geneve_gro_receive(struct sock *sk,
 	gh_len = geneve_hlen(gh);
 
 	hlen = off_gnv + gh_len;
-	if (skb_gro_header_hard(skb, hlen)) {
+	if (!skb_gro_may_pull(skb, hlen)) {
 		gh = skb_gro_header_slow(skb, hlen, off_gnv);
 		if (unlikely(!gh))
 			goto out;

include/net/gro.h

@@ -145,9 +145,10 @@ static inline void *skb_gro_header_fast(struct sk_buff *skb,
 	return NAPI_GRO_CB(skb)->frag0 + offset;
 }
 
-static inline int skb_gro_header_hard(struct sk_buff *skb, unsigned int hlen)
+static inline bool skb_gro_may_pull(const struct sk_buff *skb,
+				    unsigned int hlen)
 {
-	return NAPI_GRO_CB(skb)->frag0_len < hlen;
+	return hlen <= NAPI_GRO_CB(skb)->frag0_len;
 }
 
 static inline void skb_gro_frag0_invalidate(struct sk_buff *skb)
@@ -172,7 +173,7 @@ static inline void *skb_gro_header(struct sk_buff *skb,
 	void *ptr;
 
 	ptr = skb_gro_header_fast(skb, offset);
-	if (skb_gro_header_hard(skb, hlen))
+	if (!skb_gro_may_pull(skb, hlen))
 		ptr = skb_gro_header_slow(skb, hlen, offset);
 	return ptr;
 }

net/core/gro.c

@@ -700,7 +700,7 @@ static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
 	skb_reset_mac_header(skb);
 	skb_gro_reset_offset(skb, hlen);
 
-	if (unlikely(skb_gro_header_hard(skb, hlen))) {
+	if (unlikely(!skb_gro_may_pull(skb, hlen))) {
 		eth = skb_gro_header_slow(skb, hlen, 0);
 		if (unlikely(!eth)) {
 			net_warn_ratelimited("%s: dropping impossible skb from %s\n",

net/ipv4/fou_core.c

@@ -351,7 +351,7 @@ static struct sk_buff *gue_gro_receive(struct sock *sk,
 	optlen = guehdr->hlen << 2;
 	len += optlen;
 
-	if (skb_gro_header_hard(skb, len)) {
+	if (!skb_gro_may_pull(skb, len)) {
 		guehdr = skb_gro_header_slow(skb, len, off);
 		if (unlikely(!guehdr))
 			goto out;

net/ipv4/gre_offload.c

@@ -174,7 +174,7 @@ static struct sk_buff *gre_gro_receive(struct list_head *head,
 		grehlen += GRE_HEADER_SECTION;
 
 	hlen = off + grehlen;
-	if (skb_gro_header_hard(skb, hlen)) {
+	if (!skb_gro_may_pull(skb, hlen)) {
 		greh = skb_gro_header_slow(skb, hlen, off);
 		if (unlikely(!greh))
 			goto out;

net/ipv4/tcp_offload.c

@@ -204,7 +204,7 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb)
 		goto out;
 
 	hlen = off + thlen;
-	if (skb_gro_header_hard(skb, hlen)) {
+	if (!skb_gro_may_pull(skb, hlen)) {
 		th = skb_gro_header_slow(skb, hlen, off);
 		if (unlikely(!th))
 			goto out;