arp: use iov_tail rather than pool

The arp() function signature is changed to accept `struct iov_tail *data`
directly, replacing the previous `const struct pool *p` parameter.
Consequently, arp() no longer fetches packet data internally using
packet_data(), streamlining its logic.

This simplifies callers like tap4_handler(), which now pass the iov_tail
for the L2 ARP frame directly, removing intermediate pool handling.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

3 files changed, 7 insertions, 14 deletions

diff --git a/arp.c b/arp.c
index 8b97df6..44677ad 100644
--- a/arp.c
+++ b/arp.c
@@ -63,11 +63,11 @@ static bool ignore_arp(const struct ctx *c,
 /**
  * arp() - Check if this is a supported ARP message, reply as needed
  * @c:		Execution context
- * @p:		Packet pool, single packet with Ethernet buffer
+ * @data:	Single packet with Ethernet buffer
  *
  * Return: 1 if handled, -1 on failure
  */
-int arp(const struct ctx *c, const struct pool *p)
+int arp(const struct ctx *c, struct iov_tail *data)
 {
 	struct {
 		struct ethhdr eh;
@@ -80,14 +80,10 @@ int arp(const struct ctx *c, const struct pool *p)
 	const struct ethhdr *eh;
 	const struct arphdr *ah;
 	const struct arpmsg *am;
-	struct iov_tail data;
 
-	if (!packet_get(p, 0, &data))
-		return -1;
-
-	eh = IOV_REMOVE_HEADER(&data, eh_storage);
-	ah = IOV_REMOVE_HEADER(&data, ah_storage);
-	am = IOV_REMOVE_HEADER(&data, am_storage);
+	eh = IOV_REMOVE_HEADER(data, eh_storage);
+	ah = IOV_REMOVE_HEADER(data, ah_storage);
+	am = IOV_REMOVE_HEADER(data, am_storage);
 	if (!eh || !ah || !am)
 		return -1;
 
diff --git a/arp.h b/arp.h
index ac5cd16..86bcbf8 100644
--- a/arp.h
+++ b/arp.h
@@ -20,6 +20,6 @@ struct arpmsg {
 	unsigned char tip[4];
 } __attribute__((__packed__));
 
-int arp(const struct ctx *c, const struct pool *p);
+int arp(const struct ctx *c, struct iov_tail *data);
 
 #endif /* ARP_H */
diff --git a/tap.c b/tap.c
index 4b3f087..7a538b2 100644
--- a/tap.c
+++ b/tap.c
@@ -722,10 +722,7 @@ resume:
 		if (!eh)
 			continue;
 		if (ntohs(eh->h_proto) == ETH_P_ARP) {
-			PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
-
-			packet_add(pkt, &data);
-			arp(c, pkt);
+			arp(c, &data);
 			continue;
 		}