From: Ursula Braun <ubraun@linux.ibm.com>
Date: Thu, 14 Nov 2019 13:02:47 +0100
Subject: net/smc: immediate termination for SMCR link groups
Git-commit: 0b29ec6436138721acf5844e558f7334a0fa61d5
Patch-mainline: v5.5-rc1
References: jsc#SLE-7395

If the SMC module is unloaded or an IB device is thrown away, the
immediate link group freeing introduced for SMCD is exploited for SMCR
as well. That means SMCR-specifics are added to smc_conn_kill().

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_core.c |   58 +++++++++++++++++++++++++++++++++++------------------
 net/smc/smc_core.h |    3 +-
 net/smc/smc_ib.c   |    3 +-
 net/smc/smc_llc.c  |    4 ++-
 4 files changed, 46 insertions(+), 22 deletions(-)

--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -566,6 +566,10 @@ static void smc_lgr_cleanup(struct smc_l
 		struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
 
 		wake_up(&lnk->wr_reg_wait);
+		if (lnk->state != SMC_LNK_INACTIVE) {
+			smc_link_send_delete(lnk, false);
+			smc_llc_link_inactive(lnk);
+		}
 	}
 }
 
@@ -638,14 +642,16 @@ void smc_port_terminate(struct smc_ib_de
 	list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) {
 		if (!lgr->is_smcd &&
 		    lgr->lnk[SMC_SINGLE_LINK].smcibdev == smcibdev &&
-		    lgr->lnk[SMC_SINGLE_LINK].ibport == ibport)
+		    lgr->lnk[SMC_SINGLE_LINK].ibport == ibport) {
 			list_move(&lgr->list, &lgr_free_list);
+			lgr->freeing = 1;
+		}
 	}
 	spin_unlock_bh(&smc_lgr_list.lock);
 
 	list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
 		list_del_init(&lgr->list);
-		__smc_lgr_terminate(lgr, true);
+		__smc_lgr_terminate(lgr, false);
 	}
 }
 
@@ -695,6 +701,36 @@ void smc_smcd_terminate_all(struct smcd_
 		wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
 }
 
+/* Called when an SMCR device is removed or the smc module is unloaded.
+ * If smcibdev is given, all SMCR link groups using this device are terminated.
+ * If smcibdev is NULL, all SMCR link groups are terminated.
+ */
+void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
+{
+	struct smc_link_group *lgr, *lg;
+	LIST_HEAD(lgr_free_list);
+
+	spin_lock_bh(&smc_lgr_list.lock);
+	if (!smcibdev) {
+		list_splice_init(&smc_lgr_list.list, &lgr_free_list);
+		list_for_each_entry(lgr, &lgr_free_list, list)
+			lgr->freeing = 1;
+	} else {
+		list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
+			if (lgr->lnk[SMC_SINGLE_LINK].smcibdev == smcibdev) {
+				list_move(&lgr->list, &lgr_free_list);
+				lgr->freeing = 1;
+			}
+		}
+	}
+	spin_unlock_bh(&smc_lgr_list.lock);
+
+	list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
+		list_del_init(&lgr->list);
+		__smc_lgr_terminate(lgr, false);
+	}
+}
+
 /* Determine vlan of internal TCP socket.
  * @vlan_id: address to store the determined vlan id into
  */
@@ -1215,32 +1251,16 @@ static void smc_core_going_away(void)
 /* Clean up all SMC link groups */
 static void smc_lgrs_shutdown(void)
 {
-	struct smc_link_group *lgr, *lg;
-	LIST_HEAD(lgr_freeing_list);
 	struct smcd_dev *smcd;
 
 	smc_core_going_away();
 
-	spin_lock_bh(&smc_lgr_list.lock);
-	list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
-	spin_unlock_bh(&smc_lgr_list.lock);
+	smc_smcr_terminate_all(NULL);
 
 	spin_lock(&smcd_dev_list.lock);
 	list_for_each_entry(smcd, &smcd_dev_list.list, list)
 		smc_smcd_terminate_all(smcd);
 	spin_unlock(&smcd_dev_list.lock);
-
-	list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
-		list_del_init(&lgr->list);
-		if (!lgr->is_smcd) {
-			struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
-
-			smc_link_send_delete(&lgr->lnk[SMC_SINGLE_LINK], false);
-			smc_llc_link_inactive(lnk);
-		}
-		cancel_delayed_work_sync(&lgr->free_work);
-		smc_lgr_free(lgr); /* free link group */
-	}
 }
 
 /* Called (from smc_exit) when module is removed */
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -287,7 +287,7 @@ static inline struct smc_connection *smc
 
 static inline void smc_lgr_terminate_sched(struct smc_link_group *lgr)
 {
-	if (!lgr->terminating)
+	if (!lgr->terminating && !lgr->freeing)
 		schedule_work(&lgr->terminate_work);
 }
 
@@ -301,6 +301,7 @@ void smc_port_terminate(struct smc_ib_de
 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
 			unsigned short vlan);
 void smc_smcd_terminate_all(struct smcd_dev *dev);
+void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
 int smc_uncompress_bufsize(u8 compressed);
 int smc_rmb_rtoken_handling(struct smc_connection *conn,
--- a/net/smc/smc_ib.c
+++ b/net/smc/smc_ib.c
@@ -565,7 +565,7 @@ static void smc_ib_add_dev(struct ib_dev
 	schedule_work(&smcibdev->port_event_work);
 }
 
-/* callback function for ib_register_client() */
+/* callback function for ib_unregister_client() */
 static void smc_ib_remove_dev(struct ib_device *ibdev, void *client_data)
 {
 	struct smc_ib_device *smcibdev;
@@ -575,6 +575,7 @@ static void smc_ib_remove_dev(struct ib_
 	spin_lock(&smc_ib_devices.lock);
 	list_del_init(&smcibdev->list); /* remove from smc_ib_devices */
 	spin_unlock(&smc_ib_devices.lock);
+	smc_smcr_terminate_all(smcibdev);
 	smc_ib_cleanup_per_ibdev(smcibdev);
 	ib_unregister_event_handler(&smcibdev->event_handler);
 	kfree(smcibdev);
--- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -698,9 +698,11 @@ int smc_llc_do_confirm_rkey(struct smc_l
 int smc_llc_do_delete_rkey(struct smc_link *link,
 			   struct smc_buf_desc *rmb_desc)
 {
-	int rc;
+	int rc = 0;
 
 	mutex_lock(&link->llc_delete_rkey_mutex);
+	if (link->state != SMC_LNK_ACTIVE)
+		goto out;
 	reinit_completion(&link->llc_delete_rkey);
 	rc = smc_llc_send_delete_rkey(link, rmb_desc);
 	if (rc)