4 files changed, 33 insertions, 7 deletions

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 6d6fd1397c87..64d86298e4df 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -97,6 +97,7 @@ struct smc_link {
 	unsigned long		*wr_tx_mask;	/* bit mask of used indexes */
 	u32			wr_tx_cnt;	/* number of WR send buffers */
 	wait_queue_head_t	wr_tx_wait;	/* wait for free WR send buf */
+	atomic_t		wr_tx_refcnt;	/* tx refs to link */
 
 	struct smc_wr_buf	*wr_rx_bufs;	/* WR recv payload buffers */
 	struct ib_recv_wr	*wr_rx_ibs;	/* WR recv meta data */
@@ -109,6 +110,7 @@ struct smc_link {
 
 	struct ib_reg_wr	wr_reg;		/* WR register memory region */
 	wait_queue_head_t	wr_reg_wait;	/* wait for wr_reg result */
+	atomic_t		wr_reg_refcnt;	/* reg refs to link */
 	enum smc_wr_reg_state	wr_reg_state;	/* state of wr_reg request */
 
 	u8			gid[SMC_GID_SIZE];/* gid matching used vlan id*/
diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c
index 273eaf1bfe49..2e7560eba981 100644
--- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -888,6 +888,7 @@ int smc_llc_cli_add_link(struct smc_link *link, struct smc_llc_qentry *qentry)
 	if (!rc)
 		goto out;
 out_clear_lnk:
+	lnk_new->state = SMC_LNK_INACTIVE;
 	smcr_link_clear(lnk_new, false);
 out_reject:
 	smc_llc_cli_add_link_reject(qentry);
@@ -1184,6 +1185,7 @@ int smc_llc_srv_add_link(struct smc_link *link)
 		goto out_err;
 	return 0;
 out_err:
+	link_new->state = SMC_LNK_INACTIVE;
 	smcr_link_clear(link_new, false);
 	return rc;
 }
@@ -1286,10 +1288,8 @@ static void smc_llc_process_cli_delete_link(struct smc_link_group *lgr)
 	del_llc->reason = 0;
 	smc_llc_send_message(lnk, &qentry->msg); /* response */
 
-	if (smc_link_downing(&lnk_del->state)) {
-		if (smc_switch_conns(lgr, lnk_del, false))
-			smc_wr_tx_wait_no_pending_sends(lnk_del);
-	}
+	if (smc_link_downing(&lnk_del->state))
+		smc_switch_conns(lgr, lnk_del, false);
 	smcr_link_clear(lnk_del, true);
 
 	active_links = smc_llc_active_link_count(lgr);
@@ -1805,8 +1805,6 @@ void smc_llc_link_clear(struct smc_link *link, bool log)
 				    link->smcibdev->ibdev->name, link->ibport);
 	complete(&link->llc_testlink_resp);
 	cancel_delayed_work_sync(&link->llc_testlink_wrk);
-	smc_wr_wakeup_reg_wait(link);
-	smc_wr_wakeup_tx_wait(link);
 }
 
 /* register a new rtoken at the remote peer (for all links) */
diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c
index 289025cd545a..c79361dfcdfb 100644
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -496,7 +496,7 @@ static int smc_tx_rdma_writes(struct smc_connection *conn,
 /* Wakeup sndbuf consumers from any context (IRQ or process)
  * since there is more data to transmit; usable snd_wnd as max transmit
  */
-static int smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
+static int _smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
 {
 	struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags;
 	struct smc_link *link = conn->lnk;
@@ -550,6 +550,22 @@ out_unlock:
 	return rc;
 }
 
+static int smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
+{
+	struct smc_link *link = conn->lnk;
+	int rc = -ENOLINK;
+
+	if (!link)
+		return rc;
+
+	atomic_inc(&link->wr_tx_refcnt);
+	if (smc_link_usable(link))
+		rc = _smcr_tx_sndbuf_nonempty(conn);
+	if (atomic_dec_and_test(&link->wr_tx_refcnt))
+		wake_up_all(&link->wr_tx_wait);
+	return rc;
+}
+
 static int smcd_tx_sndbuf_nonempty(struct smc_connection *conn)
 {
 	struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags;
diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c
index cbc73a7e4d59..a419e9af36b9 100644
--- a/net/smc/smc_wr.c
+++ b/net/smc/smc_wr.c
@@ -322,9 +322,12 @@ int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr)
 	if (rc)
 		return rc;
 
+	atomic_inc(&link->wr_reg_refcnt);
 	rc = wait_event_interruptible_timeout(link->wr_reg_wait,
 					      (link->wr_reg_state != POSTED),
 					      SMC_WR_REG_MR_WAIT_TIME);
+	if (atomic_dec_and_test(&link->wr_reg_refcnt))
+		wake_up_all(&link->wr_reg_wait);
 	if (!rc) {
 		/* timeout - terminate link */
 		smcr_link_down_cond_sched(link);
@@ -566,10 +569,15 @@ void smc_wr_free_link(struct smc_link *lnk)
 		return;
 	ibdev = lnk->smcibdev->ibdev;
 
+	smc_wr_wakeup_reg_wait(lnk);
+	smc_wr_wakeup_tx_wait(lnk);
+
 	if (smc_wr_tx_wait_no_pending_sends(lnk))
 		memset(lnk->wr_tx_mask, 0,
 		       BITS_TO_LONGS(SMC_WR_BUF_CNT) *
 						sizeof(*lnk->wr_tx_mask));
+	wait_event(lnk->wr_reg_wait, (!atomic_read(&lnk->wr_reg_refcnt)));
+	wait_event(lnk->wr_tx_wait, (!atomic_read(&lnk->wr_tx_refcnt)));
 
 	if (lnk->wr_rx_dma_addr) {
 		ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
@@ -728,7 +736,9 @@ int smc_wr_create_link(struct smc_link *lnk)
 	memset(lnk->wr_tx_mask, 0,
 	       BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask));
 	init_waitqueue_head(&lnk->wr_tx_wait);
+	atomic_set(&lnk->wr_tx_refcnt, 0);
 	init_waitqueue_head(&lnk->wr_reg_wait);
+	atomic_set(&lnk->wr_reg_refcnt, 0);
 	return rc;
 
 dma_unmap: