rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs

Don't store the rxrpc protocol header in sk_buffs on the transmit queue,
but rather generate it on the fly and pass it to kernel_sendmsg() as a
separate iov.  This reduces the amount of storage required.

Note that the security header is still stored in the sk_buff as it may get
encrypted along with the data (and doesn't change with each transmission).

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 2 insertions, 9 deletions

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 7d1b998..6247ce2 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -139,7 +139,6 @@ void rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
  */
 static void rxrpc_resend(struct rxrpc_call *call)
 {
-	struct rxrpc_wire_header *whdr;
 	struct rxrpc_skb_priv *sp;
 	struct sk_buff *skb;
 	rxrpc_seq_t cursor, seq, top;
@@ -201,15 +200,8 @@ static void rxrpc_resend(struct rxrpc_call *call)
 		skb = call->rxtx_buffer[ix];
 		rxrpc_get_skb(skb, rxrpc_skb_tx_got);
 		spin_unlock_bh(&call->lock);
-		sp = rxrpc_skb(skb);
-
-		/* Each Tx packet needs a new serial number */
-		sp->hdr.serial = atomic_inc_return(&call->conn->serial);
 
-		whdr = (struct rxrpc_wire_header *)skb->head;
-		whdr->serial = htonl(sp->hdr.serial);
-
-		if (rxrpc_send_data_packet(call->conn, skb) < 0) {
+		if (rxrpc_send_data_packet(call, skb) < 0) {
 			call->resend_at = now + 2;
 			rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
 			return;
@@ -217,6 +209,7 @@ static void rxrpc_resend(struct rxrpc_call *call)
 
 		if (rxrpc_is_client_call(call))
 			rxrpc_expose_client_call(call);
+		sp = rxrpc_skb(skb);
 		sp->resend_at = now + rxrpc_resend_timeout;
 
 		rxrpc_free_skb(skb, rxrpc_skb_tx_freed);