1 files changed, 246 insertions, 64 deletions

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 05e4ffe5aabd..0fc94f296e54 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -23,6 +23,7 @@
 #include <linux/workqueue.h>
 #include <linux/in.h>
 #include <linux/sched/signal.h>
+#include <linux/if_vlan.h>
 
 #include <net/sock.h>
 #include <net/tcp.h>
@@ -35,6 +36,7 @@
 #include "smc_cdc.h"
 #include "smc_core.h"
 #include "smc_ib.h"
+#include "smc_ism.h"
 #include "smc_pnet.h"
 #include "smc_tx.h"
 #include "smc_rx.h"
@@ -342,20 +344,17 @@ static int smc_clnt_conf_first_link(struct smc_sock *smc)
 
 	rc = smc_ib_modify_qp_rts(link);
 	if (rc)
-		return SMC_CLC_DECL_INTERR;
+		return SMC_CLC_DECL_ERR_RDYLNK;
 
 	smc_wr_remember_qp_attr(link);
 
 	if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
-		return SMC_CLC_DECL_INTERR;
+		return SMC_CLC_DECL_ERR_REGRMB;
 
 	/* send CONFIRM LINK response over RoCE fabric */
-	rc = smc_llc_send_confirm_link(link,
-				       link->smcibdev->mac[link->ibport - 1],
-				       &link->smcibdev->gid[link->ibport - 1],
-				       SMC_LLC_RESP);
+	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 	if (rc < 0)
-		return SMC_CLC_DECL_TCL;
+		return SMC_CLC_DECL_TIMEOUT_CL;
 
 	/* receive ADD LINK request from server over RoCE fabric */
 	rest = wait_for_completion_interruptible_timeout(&link->llc_add,
@@ -371,18 +370,17 @@ static int smc_clnt_conf_first_link(struct smc_sock *smc)
 	/* send add link reject message, only one link supported for now */
 	rc = smc_llc_send_add_link(link,
 				   link->smcibdev->mac[link->ibport - 1],
-				   &link->smcibdev->gid[link->ibport - 1],
-				   SMC_LLC_RESP);
+				   link->gid, SMC_LLC_RESP);
 	if (rc < 0)
-		return SMC_CLC_DECL_TCL;
+		return SMC_CLC_DECL_TIMEOUT_AL;
 
 	smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 
 	return 0;
 }
 
-static void smc_conn_save_peer_info(struct smc_sock *smc,
-				    struct smc_clc_msg_accept_confirm *clc)
+static void smcr_conn_save_peer_info(struct smc_sock *smc,
+				     struct smc_clc_msg_accept_confirm *clc)
 {
 	int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
 
@@ -393,6 +391,28 @@ static void smc_conn_save_peer_info(struct smc_sock *smc,
 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 }
 
+static void smcd_conn_save_peer_info(struct smc_sock *smc,
+				     struct smc_clc_msg_accept_confirm *clc)
+{
+	int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
+
+	smc->conn.peer_rmbe_idx = clc->dmbe_idx;
+	smc->conn.peer_token = clc->token;
+	/* msg header takes up space in the buffer */
+	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
+	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
+	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
+}
+
+static void smc_conn_save_peer_info(struct smc_sock *smc,
+				    struct smc_clc_msg_accept_confirm *clc)
+{
+	if (smc->conn.lgr->is_smcd)
+		smcd_conn_save_peer_info(smc, clc);
+	else
+		smcr_conn_save_peer_info(smc, clc);
+}
+
 static void smc_link_save_peer_info(struct smc_link *link,
 				    struct smc_clc_msg_accept_confirm *clc)
 {
@@ -404,9 +424,10 @@ static void smc_link_save_peer_info(struct smc_link *link,
 }
 
 /* fall back during connect */
-static int smc_connect_fallback(struct smc_sock *smc)
+static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 {
 	smc->use_fallback = true;
+	smc->fallback_rsn = reason_code;
 	smc_copy_sock_settings_to_clc(smc);
 	if (smc->sk.sk_state == SMC_INIT)
 		smc->sk.sk_state = SMC_ACTIVE;
@@ -423,7 +444,7 @@ static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
 			sock_put(&smc->sk); /* passive closing */
 		return reason_code;
 	}
-	if (reason_code != SMC_CLC_DECL_REPLY) {
+	if (reason_code != SMC_CLC_DECL_PEERDECL) {
 		rc = smc_clc_send_decline(smc, reason_code);
 		if (rc < 0) {
 			if (smc->sk.sk_state == SMC_INIT)
@@ -431,7 +452,7 @@ static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
 			return rc;
 		}
 	}
-	return smc_connect_fallback(smc);
+	return smc_connect_fallback(smc, reason_code);
 }
 
 /* abort connecting */
@@ -448,7 +469,7 @@ static int smc_connect_abort(struct smc_sock *smc, int reason_code,
 /* check if there is a rdma device available for this connection. */
 /* called for connect and listen */
 static int smc_check_rdma(struct smc_sock *smc, struct smc_ib_device **ibdev,
-			  u8 *ibport)
+			  u8 *ibport, unsigned short vlan_id, u8 gid[])
 {
 	int reason_code = 0;
 
@@ -456,22 +477,59 @@ static int smc_check_rdma(struct smc_sock *smc, struct smc_ib_device **ibdev,
 	 * within same PNETID that also contains the ethernet device
 	 * used for the internal TCP socket
 	 */
-	smc_pnet_find_roce_resource(smc->clcsock->sk, ibdev, ibport);
+	smc_pnet_find_roce_resource(smc->clcsock->sk, ibdev, ibport, vlan_id,
+				    gid);
 	if (!(*ibdev))
 		reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 
 	return reason_code;
 }
 
+/* check if there is an ISM device available for this connection. */
+/* called for connect and listen */
+static int smc_check_ism(struct smc_sock *smc, struct smcd_dev **ismdev)
+{
+	/* Find ISM device with same PNETID as connecting interface  */
+	smc_pnet_find_ism_resource(smc->clcsock->sk, ismdev);
+	if (!(*ismdev))
+		return SMC_CLC_DECL_CNFERR; /* configuration error */
+	return 0;
+}
+
+/* Check for VLAN ID and register it on ISM device just for CLC handshake */
+static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
+				      struct smcd_dev *ismdev,
+				      unsigned short vlan_id)
+{
+	if (vlan_id && smc_ism_get_vlan(ismdev, vlan_id))
+		return SMC_CLC_DECL_CNFERR;
+	return 0;
+}
+
+/* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
+ * used, the VLAN ID will be registered again during the connection setup.
+ */
+static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
+					struct smcd_dev *ismdev,
+					unsigned short vlan_id)
+{
+	if (!is_smcd)
+		return 0;
+	if (vlan_id && smc_ism_put_vlan(ismdev, vlan_id))
+		return SMC_CLC_DECL_CNFERR;
+	return 0;
+}
+
 /* CLC handshake during connect */
-static int smc_connect_clc(struct smc_sock *smc,
+static int smc_connect_clc(struct smc_sock *smc, int smc_type,
 			   struct smc_clc_msg_accept_confirm *aclc,
-			   struct smc_ib_device *ibdev, u8 ibport)
+			   struct smc_ib_device *ibdev, u8 ibport,
+			   u8 gid[], struct smcd_dev *ismdev)
 {
 	int rc = 0;
 
 	/* do inband token exchange */
-	rc = smc_clc_send_proposal(smc, ibdev, ibport);
+	rc = smc_clc_send_proposal(smc, smc_type, ibdev, ibport, gid, ismdev);
 	if (rc)
 		return rc;
 	/* receive SMC Accept CLC message */
@@ -488,8 +546,8 @@ static int smc_connect_rdma(struct smc_sock *smc,
 	int reason_code = 0;
 
 	mutex_lock(&smc_create_lgr_pending);
-	local_contact = smc_conn_create(smc, ibdev, ibport, &aclc->lcl,
-					aclc->hdr.flag);
+	local_contact = smc_conn_create(smc, false, aclc->hdr.flag, ibdev,
+					ibport, &aclc->lcl, NULL, 0);
 	if (local_contact < 0) {
 		if (local_contact == -ENOMEM)
 			reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
@@ -504,14 +562,14 @@ static int smc_connect_rdma(struct smc_sock *smc,
 	smc_conn_save_peer_info(smc, aclc);
 
 	/* create send buffer and rmb */
-	if (smc_buf_create(smc))
+	if (smc_buf_create(smc, false))
 		return smc_connect_abort(smc, SMC_CLC_DECL_MEM, local_contact);
 
 	if (local_contact == SMC_FIRST_CONTACT)
 		smc_link_save_peer_info(link, aclc);
 
 	if (smc_rmb_rtoken_handling(&smc->conn, aclc))
-		return smc_connect_abort(smc, SMC_CLC_DECL_INTERR,
+		return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
 					 local_contact);
 
 	smc_close_init(smc);
@@ -519,12 +577,12 @@ static int smc_connect_rdma(struct smc_sock *smc,
 
 	if (local_contact == SMC_FIRST_CONTACT) {
 		if (smc_ib_ready_link(link))
-			return smc_connect_abort(smc, SMC_CLC_DECL_INTERR,
+			return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
 						 local_contact);
 	} else {
 		if (!smc->conn.rmb_desc->reused &&
 		    smc_reg_rmb(link, smc->conn.rmb_desc, true))
-			return smc_connect_abort(smc, SMC_CLC_DECL_INTERR,
+			return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
 						 local_contact);
 	}
 	smc_rmb_sync_sg_for_device(&smc->conn);
@@ -551,41 +609,113 @@ static int smc_connect_rdma(struct smc_sock *smc,
 	return 0;
 }
 
+/* setup for ISM connection of client */
+static int smc_connect_ism(struct smc_sock *smc,
+			   struct smc_clc_msg_accept_confirm *aclc,
+			   struct smcd_dev *ismdev)
+{
+	int local_contact = SMC_FIRST_CONTACT;
+	int rc = 0;
+
+	mutex_lock(&smc_create_lgr_pending);
+	local_contact = smc_conn_create(smc, true, aclc->hdr.flag, NULL, 0,
+					NULL, ismdev, aclc->gid);
+	if (local_contact < 0)
+		return smc_connect_abort(smc, SMC_CLC_DECL_MEM, 0);
+
+	/* Create send and receive buffers */
+	if (smc_buf_create(smc, true))
+		return smc_connect_abort(smc, SMC_CLC_DECL_MEM, local_contact);
+
+	smc_conn_save_peer_info(smc, aclc);
+	smc_close_init(smc);
+	smc_rx_init(smc);
+	smc_tx_init(smc);
+
+	rc = smc_clc_send_confirm(smc);
+	if (rc)
+		return smc_connect_abort(smc, rc, local_contact);
+	mutex_unlock(&smc_create_lgr_pending);
+
+	smc_copy_sock_settings_to_clc(smc);
+	if (smc->sk.sk_state == SMC_INIT)
+		smc->sk.sk_state = SMC_ACTIVE;
+
+	return 0;
+}
+
 /* perform steps before actually connecting */
 static int __smc_connect(struct smc_sock *smc)
 {
+	bool ism_supported = false, rdma_supported = false;
 	struct smc_clc_msg_accept_confirm aclc;
 	struct smc_ib_device *ibdev;
+	struct smcd_dev *ismdev;
+	u8 gid[SMC_GID_SIZE];
+	unsigned short vlan;
+	int smc_type;
 	int rc = 0;
 	u8 ibport;
 
 	sock_hold(&smc->sk); /* sock put in passive closing */
 
 	if (smc->use_fallback)
-		return smc_connect_fallback(smc);
+		return smc_connect_fallback(smc, smc->fallback_rsn);
 
 	/* if peer has not signalled SMC-capability, fall back */
 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
-		return smc_connect_fallback(smc);
+		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
 
 	/* IPSec connections opt out of SMC-R optimizations */
 	if (using_ipsec(smc))
 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
 
-	/* check if a RDMA device is available; if not, fall back */
-	if (smc_check_rdma(smc, &ibdev, &ibport))
+	/* check for VLAN ID */
+	if (smc_vlan_by_tcpsk(smc->clcsock, &vlan))
 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_CNFERR);
 
+	/* check if there is an ism device available */
+	if (!smc_check_ism(smc, &ismdev) &&
+	    !smc_connect_ism_vlan_setup(smc, ismdev, vlan)) {
+		/* ISM is supported for this connection */
+		ism_supported = true;
+		smc_type = SMC_TYPE_D;
+	}
+
+	/* check if there is a rdma device available */
+	if (!smc_check_rdma(smc, &ibdev, &ibport, vlan, gid)) {
+		/* RDMA is supported for this connection */
+		rdma_supported = true;
+		if (ism_supported)
+			smc_type = SMC_TYPE_B; /* both */
+		else
+			smc_type = SMC_TYPE_R; /* only RDMA */
+	}
+
+	/* if neither ISM nor RDMA are supported, fallback */
+	if (!rdma_supported && !ism_supported)
+		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
+
 	/* perform CLC handshake */
-	rc = smc_connect_clc(smc, &aclc, ibdev, ibport);
-	if (rc)
+	rc = smc_connect_clc(smc, smc_type, &aclc, ibdev, ibport, gid, ismdev);
+	if (rc) {
+		smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 		return smc_connect_decline_fallback(smc, rc);
+	}
 
-	/* connect using rdma */
-	rc = smc_connect_rdma(smc, &aclc, ibdev, ibport);
-	if (rc)
+	/* depending on previous steps, connect using rdma or ism */
+	if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
+		rc = smc_connect_rdma(smc, &aclc, ibdev, ibport);
+	else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
+		rc = smc_connect_ism(smc, &aclc, ismdev);
+	else
+		rc = SMC_CLC_DECL_MODEUNSUPP;
+	if (rc) {
+		smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 		return smc_connect_decline_fallback(smc, rc);
+	}
 
+	smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 	return 0;
 }
 
@@ -817,15 +947,12 @@ static int smc_serv_conf_first_link(struct smc_sock *smc)
 	link = &lgr->lnk[SMC_SINGLE_LINK];
 
 	if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
-		return SMC_CLC_DECL_INTERR;
+		return SMC_CLC_DECL_ERR_REGRMB;
 
 	/* send CONFIRM LINK request to client over the RoCE fabric */
-	rc = smc_llc_send_confirm_link(link,
-				       link->smcibdev->mac[link->ibport - 1],
-				       &link->smcibdev->gid[link->ibport - 1],
-				       SMC_LLC_REQ);
+	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
 	if (rc < 0)
-		return SMC_CLC_DECL_TCL;
+		return SMC_CLC_DECL_TIMEOUT_CL;
 
 	/* receive CONFIRM LINK response from client over the RoCE fabric */
 	rest = wait_for_completion_interruptible_timeout(
@@ -845,10 +972,9 @@ static int smc_serv_conf_first_link(struct smc_sock *smc)
 	/* send ADD LINK request to client over the RoCE fabric */
 	rc = smc_llc_send_add_link(link,
 				   link->smcibdev->mac[link->ibport - 1],
-				   &link->smcibdev->gid[link->ibport - 1],
-				   SMC_LLC_REQ);
+				   link->gid, SMC_LLC_REQ);
 	if (rc < 0)
-		return SMC_CLC_DECL_TCL;
+		return SMC_CLC_DECL_TIMEOUT_AL;
 
 	/* receive ADD LINK response from client over the RoCE fabric */
 	rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
@@ -923,7 +1049,8 @@ static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
 	}
 	smc_conn_free(&new_smc->conn);
 	new_smc->use_fallback = true;
-	if (reason_code && reason_code != SMC_CLC_DECL_REPLY) {
+	new_smc->fallback_rsn = reason_code;
+	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
 		if (smc_clc_send_decline(new_smc, reason_code) < 0) {
 			smc_listen_out_err(new_smc);
 			return;
@@ -953,7 +1080,8 @@ static int smc_listen_rdma_init(struct smc_sock *new_smc,
 				int *local_contact)
 {
 	/* allocate connection / link group */
-	*local_contact = smc_conn_create(new_smc, ibdev, ibport, &pclc->lcl, 0);
+	*local_contact = smc_conn_create(new_smc, false, 0, ibdev, ibport,
+					 &pclc->lcl, NULL, 0);
 	if (*local_contact < 0) {
 		if (*local_contact == -ENOMEM)
 			return SMC_CLC_DECL_MEM;/* insufficient memory*/
@@ -961,12 +1089,50 @@ static int smc_listen_rdma_init(struct smc_sock *new_smc,
 	}
 
 	/* create send buffer and rmb */
-	if (smc_buf_create(new_smc))
+	if (smc_buf_create(new_smc, false))
 		return SMC_CLC_DECL_MEM;
 
 	return 0;
 }
 
+/* listen worker: initialize connection and buffers for SMC-D */
+static int smc_listen_ism_init(struct smc_sock *new_smc,
+			       struct smc_clc_msg_proposal *pclc,
+			       struct smcd_dev *ismdev,
+			       int *local_contact)
+{
+	struct smc_clc_msg_smcd *pclc_smcd;
+
+	pclc_smcd = smc_get_clc_msg_smcd(pclc);
+	*local_contact = smc_conn_create(new_smc, true, 0, NULL, 0, NULL,
+					 ismdev, pclc_smcd->gid);
+	if (*local_contact < 0) {
+		if (*local_contact == -ENOMEM)
+			return SMC_CLC_DECL_MEM;/* insufficient memory*/
+		return SMC_CLC_DECL_INTERR; /* other error */
+	}
+
+	/* Check if peer can be reached via ISM device */
+	if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
+			    new_smc->conn.lgr->vlan_id,
+			    new_smc->conn.lgr->smcd)) {
+		if (*local_contact == SMC_FIRST_CONTACT)
+			smc_lgr_forget(new_smc->conn.lgr);
+		smc_conn_free(&new_smc->conn);
+		return SMC_CLC_DECL_CNFERR;
+	}
+
+	/* Create send and receive buffers */
+	if (smc_buf_create(new_smc, true)) {
+		if (*local_contact == SMC_FIRST_CONTACT)
+			smc_lgr_forget(new_smc->conn.lgr);
+		smc_conn_free(&new_smc->conn);
+		return SMC_CLC_DECL_MEM;
+	}
+
+	return 0;
+}
+
 /* listen worker: register buffers */
 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
 {
@@ -975,7 +1141,7 @@ static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
 	if (local_contact != SMC_FIRST_CONTACT) {
 		if (!new_smc->conn.rmb_desc->reused) {
 			if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
-				return SMC_CLC_DECL_INTERR;
+				return SMC_CLC_DECL_ERR_REGRMB;
 		}
 	}
 	smc_rmb_sync_sg_for_device(&new_smc->conn);
@@ -995,13 +1161,13 @@ static void smc_listen_rdma_finish(struct smc_sock *new_smc,
 		smc_link_save_peer_info(link, cclc);
 
 	if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
-		reason_code = SMC_CLC_DECL_INTERR;
+		reason_code = SMC_CLC_DECL_ERR_RTOK;
 		goto decline;
 	}
 
 	if (local_contact == SMC_FIRST_CONTACT) {
 		if (smc_ib_ready_link(link)) {
-			reason_code = SMC_CLC_DECL_INTERR;
+			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
 			goto decline;
 		}
 		/* QP confirmation over RoCE fabric */
@@ -1025,8 +1191,11 @@ static void smc_listen_work(struct work_struct *work)
 	struct smc_clc_msg_accept_confirm cclc;
 	struct smc_clc_msg_proposal *pclc;
 	struct smc_ib_device *ibdev;
+	bool ism_supported = false;
+	struct smcd_dev *ismdev;
 	u8 buf[SMC_CLC_MAX_LEN];
 	int local_contact = 0;
+	unsigned short vlan;
 	int reason_code = 0;
 	int rc = 0;
 	u8 ibport;
@@ -1039,6 +1208,7 @@ static void smc_listen_work(struct work_struct *work)
 	/* check if peer is smc capable */
 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
 		new_smc->use_fallback = true;
+		new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
 		smc_listen_out_connected(new_smc);
 		return;
 	}
@@ -1065,15 +1235,26 @@ static void smc_listen_work(struct work_struct *work)
 	smc_rx_init(new_smc);
 	smc_tx_init(new_smc);
 
+	/* check if ISM is available */
+	if ((pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) &&
+	    !smc_check_ism(new_smc, &ismdev) &&
+	    !smc_listen_ism_init(new_smc, pclc, ismdev, &local_contact)) {
+		ism_supported = true;
+	}
+
 	/* check if RDMA is available */
-	if (smc_check_rdma(new_smc, &ibdev, &ibport) ||
-	    smc_listen_rdma_check(new_smc, pclc) ||
-	    smc_listen_rdma_init(new_smc, pclc, ibdev, ibport,
-				 &local_contact) ||
-	    smc_listen_rdma_reg(new_smc, local_contact)) {
+	if (!ism_supported &&
+	    ((pclc->hdr.path != SMC_TYPE_R && pclc->hdr.path != SMC_TYPE_B) ||
+	     smc_vlan_by_tcpsk(new_smc->clcsock, &vlan) ||
+	     smc_check_rdma(new_smc, &ibdev, &ibport, vlan, NULL) ||
+	     smc_listen_rdma_check(new_smc, pclc) ||
+	     smc_listen_rdma_init(new_smc, pclc, ibdev, ibport,
+				  &local_contact) ||
+	     smc_listen_rdma_reg(new_smc, local_contact))) {
 		/* SMC not supported, decline */
 		mutex_unlock(&smc_create_lgr_pending);
-		smc_listen_decline(new_smc, SMC_CLC_DECL_CNFERR, local_contact);
+		smc_listen_decline(new_smc, SMC_CLC_DECL_MODEUNSUPP,
+				   local_contact);
 		return;
 	}
 
@@ -1095,7 +1276,8 @@ static void smc_listen_work(struct work_struct *work)
 	}
 
 	/* finish worker */
-	smc_listen_rdma_finish(new_smc, &cclc, local_contact);
+	if (!ism_supported)
+		smc_listen_rdma_finish(new_smc, &cclc, local_contact);
 	smc_conn_save_peer_info(new_smc, &cclc);
 	mutex_unlock(&smc_create_lgr_pending);
 	smc_listen_out_connected(new_smc);
@@ -1119,6 +1301,7 @@ static void smc_tcp_listen_work(struct work_struct *work)
 
 		new_smc->listen_smc = lsmc;
 		new_smc->use_fallback = lsmc->use_fallback;
+		new_smc->fallback_rsn = lsmc->fallback_rsn;
 		sock_hold(lsk); /* sock_put in smc_listen_work */
 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
 		smc_copy_sock_settings_to_smc(new_smc);
@@ -1273,6 +1456,7 @@ static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
 	if (msg->msg_flags & MSG_FASTOPEN) {
 		if (sk->sk_state == SMC_INIT) {
 			smc->use_fallback = true;
+			smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
 		} else {
 			rc = -EINVAL;
 			goto out;
@@ -1351,7 +1535,7 @@ static __poll_t smc_poll(struct file *file, struct socket *sock,
 			mask |= EPOLLERR;
 	} else {
 		if (sk->sk_state != SMC_CLOSED)
-			sock_poll_wait(file, sk_sleep(sk), wait);
+			sock_poll_wait(file, wait);
 		if (sk->sk_err)
 			mask |= EPOLLERR;
 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
@@ -1470,6 +1654,7 @@ static int smc_setsockopt(struct socket *sock, int level, int optname,
 		/* option not supported by SMC */
 		if (sk->sk_state == SMC_INIT) {
 			smc->use_fallback = true;
+			smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
 		} else {
 			if (!smc->use_fallback)
 				rc = -EINVAL;
@@ -1573,12 +1758,8 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd,
 		    smc->sk.sk_state == SMC_CLOSED) {
 			answ = 0;
 		} else {
-			smc_curs_write(&cons,
-			       smc_curs_read(&conn->local_tx_ctrl.cons, conn),
-				       conn);
-			smc_curs_write(&urg,
-				       smc_curs_read(&conn->urg_curs, conn),
-				       conn);
+			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
+			smc_curs_copy(&urg, &conn->urg_curs, conn);
 			answ = smc_curs_diff(conn->rmb_desc->len,
 					     &cons, &urg) == 1;
 		}
@@ -1711,6 +1892,7 @@ static int smc_create(struct net *net, struct socket *sock, int protocol,
 	/* create internal TCP socket for CLC handshake and fallback */
 	smc = smc_sk(sk);
 	smc->use_fallback = false; /* assume rdma capability first */
+	smc->fallback_rsn = 0;
 	rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
 			      &smc->clcsock);
 	if (rc) {