[PATCH net-next 1/3] net/smc: consolidate unlocking in same function

[Karsten Graul <kgraul@xxxxxxxxxxxxx>]

Static code checkers warn of inconsistent returns because the lgr mutex
is locked in one function and unlocked in a function called by the
locking function:
net/smc/af_smc.c:823 smc_connect_rdma() warn: inconsistent returns 'smc_client_lgr_pending'.
net/smc/af_smc.c:897 smc_connect_ism() warn: inconsistent returns 'smc_server_lgr_pending'.

Make the code consistent by doing the unlock in the same function that
fetches the lock. No functional changes.

Signed-off-by: Karsten Graul <kgraul@xxxxxxxxxxxxx>
---
 net/smc/af_smc.c | 77 +++++++++++++++++++++++++-----------------------
 1 file changed, 40 insertions(+), 37 deletions(-)

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 670e802a73cb..fbe98bb20299 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -553,23 +553,12 @@ static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
 }
 
 /* abort connecting */
-static int smc_connect_abort(struct smc_sock *smc, int reason_code,
-			     int local_first)
+static void smc_connect_abort(struct smc_sock *smc, int local_first)
 {
-	bool is_smcd = smc->conn.lgr->is_smcd;
-
 	if (local_first)
 		smc_lgr_cleanup_early(&smc->conn);
 	else
 		smc_conn_free(&smc->conn);
-	if (is_smcd)
-		/* there is only one lgr role for SMC-D; use server lock */
-		mutex_unlock(&smc_server_lgr_pending);
-	else
-		mutex_unlock(&smc_client_lgr_pending);
-
-	smc->connect_nonblock = 0;
-	return reason_code;
 }
 
 /* check if there is a rdma device available for this connection. */
@@ -764,43 +753,47 @@ static int smc_connect_rdma(struct smc_sock *smc,
 				break;
 			}
 		}
-		if (!link)
-			return smc_connect_abort(smc, SMC_CLC_DECL_NOSRVLINK,
-						 ini->first_contact_local);
+		if (!link) {
+			reason_code = SMC_CLC_DECL_NOSRVLINK;
+			goto connect_abort;
+		}
 		smc->conn.lnk = link;
 	}
 
 	/* create send buffer and rmb */
-	if (smc_buf_create(smc, false))
-		return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
-					 ini->first_contact_local);
+	if (smc_buf_create(smc, false)) {
+		reason_code = SMC_CLC_DECL_MEM;
+		goto connect_abort;
+	}
 
 	if (ini->first_contact_local)
 		smc_link_save_peer_info(link, aclc);
 
-	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc))
-		return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
-					 ini->first_contact_local);
+	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
+		reason_code = SMC_CLC_DECL_ERR_RTOK;
+		goto connect_abort;
+	}
 
 	smc_close_init(smc);
 	smc_rx_init(smc);
 
 	if (ini->first_contact_local) {
-		if (smc_ib_ready_link(link))
-			return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
-						 ini->first_contact_local);
+		if (smc_ib_ready_link(link)) {
+			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
+			goto connect_abort;
+		}
 	} else {
-		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc))
-			return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
-						 ini->first_contact_local);
+		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
+			reason_code = SMC_CLC_DECL_ERR_REGRMB;
+			goto connect_abort;
+		}
 	}
 	smc_rmb_sync_sg_for_device(&smc->conn);
 
 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
 					   SMC_V1);
 	if (reason_code)
-		return smc_connect_abort(smc, reason_code,
-					 ini->first_contact_local);
+		goto connect_abort;
 
 	smc_tx_init(smc);
 
@@ -810,8 +803,7 @@ static int smc_connect_rdma(struct smc_sock *smc,
 		reason_code = smcr_clnt_conf_first_link(smc);
 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
 		if (reason_code)
-			return smc_connect_abort(smc, reason_code,
-						 ini->first_contact_local);
+			goto connect_abort;
 	}
 	mutex_unlock(&smc_client_lgr_pending);
 
@@ -821,6 +813,12 @@ static int smc_connect_rdma(struct smc_sock *smc,
 		smc->sk.sk_state = SMC_ACTIVE;
 
 	return 0;
+connect_abort:
+	smc_connect_abort(smc, ini->first_contact_local);
+	mutex_unlock(&smc_client_lgr_pending);
+	smc->connect_nonblock = 0;
+
+	return reason_code;
 }
 
 /* The server has chosen one of the proposed ISM devices for the communication.
@@ -872,11 +870,10 @@ static int smc_connect_ism(struct smc_sock *smc,
 
 	/* Create send and receive buffers */
 	rc = smc_buf_create(smc, true);
-	if (rc)
-		return smc_connect_abort(smc, (rc == -ENOSPC) ?
-					      SMC_CLC_DECL_MAX_DMB :
-					      SMC_CLC_DECL_MEM,
-					 ini->first_contact_local);
+	if (rc) {
+		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
+		goto connect_abort;
+	}
 
 	smc_conn_save_peer_info(smc, aclc);
 	smc_close_init(smc);
@@ -886,7 +883,7 @@ static int smc_connect_ism(struct smc_sock *smc,
 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
 				  aclc->hdr.version);
 	if (rc)
-		return smc_connect_abort(smc, rc, ini->first_contact_local);
+		goto connect_abort;
 	mutex_unlock(&smc_server_lgr_pending);
 
 	smc_copy_sock_settings_to_clc(smc);
@@ -895,6 +892,12 @@ static int smc_connect_ism(struct smc_sock *smc,
 		smc->sk.sk_state = SMC_ACTIVE;
 
 	return 0;
+connect_abort:
+	smc_connect_abort(smc, ini->first_contact_local);
+	mutex_unlock(&smc_server_lgr_pending);
+	smc->connect_nonblock = 0;
+
+	return rc;
 }
 
 /* check if received accept type and version matches a proposed one */
-- 
2.17.1