From: Ursula Braun <ubraun@linux.ibm.com>
Date: Thu, 14 Nov 2019 13:02:40 +0100
Subject: net/smc: fix final cleanup sequence for SMCD devices
Git-commit: 50c6b20eff8e10cb91f06262d8003a5d9be3dfab
Patch-mainline: v5.5-rc1
References: jsc#SLE-7395

If peer announces shutdown, use the link group terminate worker for
local cleanup of link groups and connections to terminate link group
in proper context.

Make sure link groups are cleaned up first before destroying the
event queue of the SMCD device, because link group cleanup may
raise events.

Send signal shutdown only if peer has not done it already.

Send socket abort or close only, if peer has not already announced
shutdown.

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>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 net/smc/smc_cdc.c  |    3 +++
 net/smc/smc_core.c |   18 +++++++++++-------
 net/smc/smc_core.h |    2 ++
 net/smc/smc_ism.c  |    7 +++++--
 4 files changed, 21 insertions(+), 9 deletions(-)

--- a/net/smc/smc_cdc.c
+++ b/net/smc/smc_cdc.c
@@ -131,6 +131,9 @@ int smc_cdc_get_slot_and_msg_send(struct
 {
 	int rc;
 
+	if (!conn->lgr || (conn->lgr->is_smcd && conn->lgr->peer_shutdown))
+		return -EPIPE;
+
 	if (conn->lgr->is_smcd) {
 		spin_lock_bh(&conn->send_lock);
 		rc = smcd_cdc_msg_send(conn);
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -275,6 +275,7 @@ static int smc_lgr_create(struct smc_soc
 		lgr->smcd = ini->ism_dev;
 		lgr_list = &ini->ism_dev->lgr_list;
 		lgr_lock = &lgr->smcd->lgr_lock;
+		lgr->peer_shutdown = 0;
 	} else {
 		/* SMC-R specific settings */
 		get_device(&ini->ib_dev->ibdev->dev);
@@ -514,11 +515,16 @@ static void smc_conn_kill(struct smc_con
 {
 	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 
-	smc_close_abort(conn);
+	if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
+		conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
+	else
+		smc_close_abort(conn);
 	conn->killed = 1;
+	smc->sk.sk_err = ECONNABORTED;
 	smc_sk_wake_ups(smc);
+	if (conn->lgr->is_smcd)
+		tasklet_kill(&conn->rx_tsklet);
 	smc_lgr_unregister_conn(conn);
-	smc->sk.sk_err = ECONNABORTED;
 	smc_close_active_abort(smc);
 }
 
@@ -604,6 +610,8 @@ void smc_smcd_terminate(struct smcd_dev
 	list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
 		if ((!peer_gid || lgr->peer_gid == peer_gid) &&
 		    (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
+			if (peer_gid) /* peer triggered termination */
+				lgr->peer_shutdown = 1;
 			list_move(&lgr->list, &lgr_free_list);
 		}
 	}
@@ -612,11 +620,7 @@ void smc_smcd_terminate(struct smcd_dev
 	/* cancel the regular free workers and actually free lgrs */
 	list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
 		list_del_init(&lgr->list);
-		__smc_lgr_terminate(lgr);
-		cancel_delayed_work_sync(&lgr->free_work);
-		if (!peer_gid && vlan == VLAN_VID_MASK) /* dev terminated? */
-			smc_ism_signal_shutdown(lgr);
-		smc_lgr_free(lgr);
+		schedule_work(&lgr->terminate_work);
 	}
 }
 
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -228,6 +228,8 @@ struct smc_link_group {
 						/* Peer GID (remote) */
 			struct smcd_dev		*smcd;
 						/* ISM device for VLAN reg. */
+			u8			peer_shutdown : 1;
+						/* peer triggered shutdownn */
 		};
 	};
 };
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -226,6 +226,9 @@ int smc_ism_signal_shutdown(struct smc_l
 	int rc;
 	union smcd_sw_event_info ev_info;
 
+	if (lgr->peer_shutdown)
+		return 0;
+
 	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
 	ev_info.vlan_id = lgr->vlan_id;
 	ev_info.code = ISM_EVENT_REQUEST;
@@ -313,12 +316,12 @@ EXPORT_SYMBOL_GPL(smcd_register_dev);
 void smcd_unregister_dev(struct smcd_dev *smcd)
 {
 	spin_lock(&smcd_dev_list.lock);
-	list_del(&smcd->list);
+	list_del_init(&smcd->list);
 	spin_unlock(&smcd_dev_list.lock);
 	smcd->going_away = 1;
+	smc_smcd_terminate(smcd, 0, VLAN_VID_MASK);
 	flush_workqueue(smcd->event_wq);
 	destroy_workqueue(smcd->event_wq);
-	smc_smcd_terminate(smcd, 0, VLAN_VID_MASK);
 
 	device_del(&smcd->dev);
 }