net/smc: Correct smc link connection counter in case of smc client

SMC clients may be assigned to a different link after the initial
connection between two peers was established. In such a case,
the connection counter was not correctly set.

Update the connection counter correctly when a smc client connection
is assigned to a different smc link.

Fixes: 07d51580 ("net/smc: Add connection counters for links")
Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Tested-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/smc/af_smc.c

@@ -795,7 +795,7 @@ static int smc_connect_rdma(struct smc_sock *smc,
 			reason_code = SMC_CLC_DECL_NOSRVLINK;
 			goto connect_abort;
 		}
-		smc->conn.lnk = link;
+		smc_switch_link_and_count(&smc->conn, link);
 	}
 
 	/* create send buffer and rmb */

net/smc/smc_core.c

@@ -917,7 +917,7 @@ static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
 	return rc;
 }
 
-static void smc_switch_link_and_count(struct smc_connection *conn,
+void smc_switch_link_and_count(struct smc_connection *conn,
 			       struct smc_link *to_lnk)
 {
 	atomic_dec(&conn->lnk->conn_cnt);

net/smc/smc_core.h

@@ -446,6 +446,8 @@ void smc_core_exit(void);
 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 		   u8 link_idx, struct smc_init_info *ini);
 void smcr_link_clear(struct smc_link *lnk, bool log);
+void smc_switch_link_and_count(struct smc_connection *conn,
+			       struct smc_link *to_lnk);
 int smcr_buf_map_lgr(struct smc_link *lnk);
 int smcr_buf_reg_lgr(struct smc_link *lnk);
 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type);