1 files changed, 39 insertions, 19 deletions

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index e066899de72d..086d9913975d 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -165,10 +165,9 @@ static int smc_release(struct socket *sock)
 
 	if (sk->sk_state == SMC_CLOSED) {
 		if (smc->clcsock) {
-			mutex_lock(&smc->clcsock_release_lock);
-			sock_release(smc->clcsock);
-			smc->clcsock = NULL;
-			mutex_unlock(&smc->clcsock_release_lock);
+			release_sock(sk);
+			smc_clcsock_release(smc);
+			lock_sock(sk);
 		}
 		if (!smc->use_fallback)
 			smc_conn_free(&smc->conn);
@@ -444,10 +443,19 @@ static void smc_link_save_peer_info(struct smc_link *link,
 	link->peer_mtu = clc->qp_mtu;
 }
 
+static void smc_switch_to_fallback(struct smc_sock *smc)
+{
+	smc->use_fallback = true;
+	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
+		smc->clcsock->file = smc->sk.sk_socket->file;
+		smc->clcsock->file->private_data = smc->clcsock;
+	}
+}
+
 /* fall back during connect */
 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 {
-	smc->use_fallback = true;
+	smc_switch_to_fallback(smc);
 	smc->fallback_rsn = reason_code;
 	smc_copy_sock_settings_to_clc(smc);
 	smc->connect_nonblock = 0;
@@ -780,10 +788,14 @@ static void smc_connect_work(struct work_struct *work)
 		smc->sk.sk_err = -rc;
 
 out:
-	if (smc->sk.sk_err)
-		smc->sk.sk_state_change(&smc->sk);
-	else
-		smc->sk.sk_write_space(&smc->sk);
+	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
+		if (smc->sk.sk_err) {
+			smc->sk.sk_state_change(&smc->sk);
+		} else { /* allow polling before and after fallback decision */
+			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
+			smc->sk.sk_write_space(&smc->sk);
+		}
+	}
 	release_sock(&smc->sk);
 }
 
@@ -867,11 +879,11 @@ static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 	if  (rc < 0)
 		lsk->sk_err = -rc;
 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
+		new_sk->sk_prot->unhash(new_sk);
 		if (new_clcsock)
 			sock_release(new_clcsock);
 		new_sk->sk_state = SMC_CLOSED;
 		sock_set_flag(new_sk, SOCK_DEAD);
-		new_sk->sk_prot->unhash(new_sk);
 		sock_put(new_sk); /* final */
 		*new_smc = NULL;
 		goto out;
@@ -922,16 +934,21 @@ struct sock *smc_accept_dequeue(struct sock *parent,
 
 		smc_accept_unlink(new_sk);
 		if (new_sk->sk_state == SMC_CLOSED) {
+			new_sk->sk_prot->unhash(new_sk);
 			if (isk->clcsock) {
 				sock_release(isk->clcsock);
 				isk->clcsock = NULL;
 			}
-			new_sk->sk_prot->unhash(new_sk);
 			sock_put(new_sk); /* final */
 			continue;
 		}
-		if (new_sock)
+		if (new_sock) {
 			sock_graft(new_sk, new_sock);
+			if (isk->use_fallback) {
+				smc_sk(new_sk)->clcsock->file = new_sock->file;
+				isk->clcsock->file->private_data = isk->clcsock;
+			}
+		}
 		return new_sk;
 	}
 	return NULL;
@@ -951,6 +968,7 @@ void smc_close_non_accepted(struct sock *sk)
 		sock_set_flag(sk, SOCK_DEAD);
 		sk->sk_shutdown |= SHUTDOWN_MASK;
 	}
+	sk->sk_prot->unhash(sk);
 	if (smc->clcsock) {
 		struct socket *tcp;
 
@@ -966,7 +984,6 @@ void smc_close_non_accepted(struct sock *sk)
 			smc_conn_free(&smc->conn);
 	}
 	release_sock(sk);
-	sk->sk_prot->unhash(sk);
 	sock_put(sk); /* final sock_put */
 }
 
@@ -1032,13 +1049,13 @@ static void smc_listen_out(struct smc_sock *new_smc)
 	struct smc_sock *lsmc = new_smc->listen_smc;
 	struct sock *newsmcsk = &new_smc->sk;
 
-	lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
 	if (lsmc->sk.sk_state == SMC_LISTEN) {
+		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
+		release_sock(&lsmc->sk);
 	} else { /* no longer listening */
 		smc_close_non_accepted(newsmcsk);
 	}
-	release_sock(&lsmc->sk);
 
 	/* Wake up accept */
 	lsmc->sk.sk_data_ready(&lsmc->sk);
@@ -1082,7 +1099,7 @@ static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
 		return;
 	}
 	smc_conn_free(&new_smc->conn);
-	new_smc->use_fallback = true;
+	smc_switch_to_fallback(new_smc);
 	new_smc->fallback_rsn = reason_code;
 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
 		if (smc_clc_send_decline(new_smc, reason_code) < 0) {
@@ -1220,6 +1237,9 @@ static void smc_listen_work(struct work_struct *work)
 	u8 buf[SMC_CLC_MAX_LEN];
 	int rc = 0;
 
+	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
+		return smc_listen_out_err(new_smc);
+
 	if (new_smc->use_fallback) {
 		smc_listen_out_connected(new_smc);
 		return;
@@ -1227,7 +1247,7 @@ static void smc_listen_work(struct work_struct *work)
 
 	/* check if peer is smc capable */
 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
-		new_smc->use_fallback = true;
+		smc_switch_to_fallback(new_smc);
 		new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
 		smc_listen_out_connected(new_smc);
 		return;
@@ -1507,7 +1527,7 @@ static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
 
 	if (msg->msg_flags & MSG_FASTOPEN) {
 		if (sk->sk_state == SMC_INIT) {
-			smc->use_fallback = true;
+			smc_switch_to_fallback(smc);
 			smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
 		} else {
 			rc = -EINVAL;
@@ -1712,7 +1732,7 @@ static int smc_setsockopt(struct socket *sock, int level, int optname,
 	case TCP_FASTOPEN_NO_COOKIE:
 		/* option not supported by SMC */
 		if (sk->sk_state == SMC_INIT) {
-			smc->use_fallback = true;
+			smc_switch_to_fallback(smc);
 			smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
 		} else {
 			if (!smc->use_fallback)