mptcp: use plain bool instead of custom binary enum

The 'data_avail' subflow field is already used as plain boolean,
drop the custom binary enum type and switch to bool.

No functional changed intended.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-2-v1-3-9dc60939d371@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/mptcp/protocol.h

@@ -434,11 +434,6 @@ mptcp_subflow_rsk(const struct request_sock *rsk)
 	return (struct mptcp_subflow_request_sock *)rsk;
 }
 
-enum mptcp_data_avail {
-	MPTCP_SUBFLOW_NODATA,
-	MPTCP_SUBFLOW_DATA_AVAIL,
-};
-
 struct mptcp_delegated_action {
 	struct napi_struct napi;
 	struct list_head head;
@@ -494,7 +489,7 @@ struct mptcp_subflow_context {
 		valid_csum_seen : 1,        /* at least one csum validated */
 		is_mptfo : 1,	    /* subflow is doing TFO */
 		__unused : 9;
-	enum mptcp_data_avail data_avail;
+	bool	data_avail;
 	bool	scheduled;
 	u32	remote_nonce;
 	u64	thmac;

net/mptcp/subflow.c

@@ -1237,7 +1237,7 @@ static bool subflow_check_data_avail(struct sock *ssk)
 	struct sk_buff *skb;
 
 	if (!skb_peek(&ssk->sk_receive_queue))
-		WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
+		WRITE_ONCE(subflow->data_avail, false);
 	if (subflow->data_avail)
 		return true;
 
@@ -1271,7 +1271,7 @@ static bool subflow_check_data_avail(struct sock *ssk)
 			continue;
 		}
 
-		WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL);
+		WRITE_ONCE(subflow->data_avail, true);
 		break;
 	}
 	return true;
@@ -1293,7 +1293,7 @@ static bool subflow_check_data_avail(struct sock *ssk)
 				goto reset;
 			}
 			mptcp_subflow_fail(msk, ssk);
-			WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL);
+			WRITE_ONCE(subflow->data_avail, true);
 			return true;
 		}
 
@@ -1310,7 +1310,7 @@ static bool subflow_check_data_avail(struct sock *ssk)
 			while ((skb = skb_peek(&ssk->sk_receive_queue)))
 				sk_eat_skb(ssk, skb);
 			tcp_send_active_reset(ssk, GFP_ATOMIC);
-			WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
+			WRITE_ONCE(subflow->data_avail, false);
 			return false;
 		}
 
@@ -1322,7 +1322,7 @@ static bool subflow_check_data_avail(struct sock *ssk)
 	subflow->map_seq = READ_ONCE(msk->ack_seq);
 	subflow->map_data_len = skb->len;
 	subflow->map_subflow_seq = tcp_sk(ssk)->copied_seq - subflow->ssn_offset;
-	WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL);
+	WRITE_ONCE(subflow->data_avail, true);
 	return true;
 }
 
@@ -1334,7 +1334,7 @@ bool mptcp_subflow_data_available(struct sock *sk)
 	if (subflow->map_valid &&
 	    mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len) {
 		subflow->map_valid = 0;
-		WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
+		WRITE_ONCE(subflow->data_avail, false);
 
 		pr_debug("Done with mapping: seq=%u data_len=%u",
 			 subflow->map_subflow_seq,