net/smc: immediate termination for SMCD link groups

SMCD link group termination is called when peer signals its shutdown
of its corresponding link group. For regular shutdowns no connections
exist anymore. For abnormal shutdowns connections must be killed and
their DMBs must be unregistered immediately. That means the SMCR method
to delay the link group freeing several seconds does not fit.

This patch adds immediate termination of a link group and its SMCD
connections and makes sure all SMCD link group related cleanup steps
are finished.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 39 insertions, 7 deletions

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 561f069b30de..9d6da2c7413d 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -214,7 +214,7 @@ static void smc_lgr_free_work(struct work_struct *work)
 
 	if (!lgr->is_smcd && lnk->state != SMC_LNK_INACTIVE)
 		smc_llc_link_inactive(lnk);
-	if (lgr->is_smcd)
+	if (lgr->is_smcd && !lgr->terminating)
 		smc_ism_signal_shutdown(lgr);
 	smc_lgr_free(lgr);
 }
@@ -381,7 +381,8 @@ void smc_conn_free(struct smc_connection *conn)
 	if (!lgr)
 		return;
 	if (lgr->is_smcd) {
-		smc_ism_unset_conn(conn);
+		if (!list_empty(&lgr->list))
+			smc_ism_unset_conn(conn);
 		tasklet_kill(&conn->rx_tsklet);
 	} else {
 		smc_cdc_tx_dismiss_slots(conn);
@@ -481,8 +482,10 @@ static void smc_lgr_free(struct smc_link_group *lgr)
 {
 	smc_lgr_free_bufs(lgr);
 	if (lgr->is_smcd) {
-		smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
-		put_device(&lgr->smcd->dev);
+		if (!lgr->terminating) {
+			smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
+			put_device(&lgr->smcd->dev);
+		}
 	} else {
 		smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]);
 		put_device(&lgr->lnk[SMC_SINGLE_LINK].smcibdev->ibdev->dev);
@@ -503,6 +506,20 @@ void smc_lgr_forget(struct smc_link_group *lgr)
 	spin_unlock_bh(lgr_lock);
 }
 
+static void smcd_unregister_all_dmbs(struct smc_link_group *lgr)
+{
+	int i;
+
+	for (i = 0; i < SMC_RMBE_SIZES; i++) {
+		struct smc_buf_desc *buf_desc;
+
+		list_for_each_entry(buf_desc, &lgr->rmbs[i], list) {
+			buf_desc->len += sizeof(struct smcd_cdc_msg);
+			smc_ism_unregister_dmb(lgr->smcd, buf_desc);
+		}
+	}
+}
+
 static void smc_sk_wake_ups(struct smc_sock *smc)
 {
 	smc->sk.sk_write_space(&smc->sk);
@@ -522,12 +539,28 @@ static void smc_conn_kill(struct smc_connection *conn)
 	conn->killed = 1;
 	smc->sk.sk_err = ECONNABORTED;
 	smc_sk_wake_ups(smc);
-	if (conn->lgr->is_smcd)
+	if (conn->lgr->is_smcd) {
+		smc_ism_unset_conn(conn);
 		tasklet_kill(&conn->rx_tsklet);
+	}
 	smc_lgr_unregister_conn(conn);
 	smc_close_active_abort(smc);
 }
 
+static void smc_lgr_cleanup(struct smc_link_group *lgr)
+{
+	if (lgr->is_smcd) {
+		smc_ism_signal_shutdown(lgr);
+		smcd_unregister_all_dmbs(lgr);
+		smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
+		put_device(&lgr->smcd->dev);
+	} else {
+		struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
+
+		wake_up(&lnk->wr_reg_wait);
+	}
+}
+
 /* terminate link group */
 static void __smc_lgr_terminate(struct smc_link_group *lgr)
 {
@@ -557,8 +590,7 @@ static void __smc_lgr_terminate(struct smc_link_group *lgr)
 		node = rb_first(&lgr->conns_all);
 	}
 	read_unlock_bh(&lgr->conns_lock);
-	if (!lgr->is_smcd)
-		wake_up(&lgr->lnk[SMC_SINGLE_LINK].wr_reg_wait);
+	smc_lgr_cleanup(lgr);
 	smc_lgr_schedule_free_work_fast(lgr);
 }