diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h
index 3a4f7cd..25eab1e 100644
--- a/include/linux/btf_ids.h
+++ b/include/linux/btf_ids.h
@@ -264,6 +264,21 @@ enum {
 MAX_BTF_TRACING_TYPE,
 };
 
+#if IS_ENABLED(CONFIG_SMC)
+#define BTF_SMC_TYPE_xxx		\
+	BTF_SMC_TYPE(BTF_SMC_TYPE_SOCK, smc_sock)		\
+	BTF_SMC_TYPE(BTF_SMC_TYPE_CONNECTION, smc_connection)	\
+	BTF_SMC_TYPE(BTF_SMC_TYPE_HOST_CURSOR, smc_host_cursor)
+
+enum {
+#define BTF_SMC_TYPE(name, type) name,
+BTF_SMC_TYPE_xxx
+#undef BTF_SMC_TYPE
+MAX_BTF_SMC_TYPE,
+};
+extern u32 btf_smc_ids[];
+#endif
+
 extern u32 btf_tracing_ids[];
 extern u32 bpf_cgroup_btf_id[];
 extern u32 bpf_local_storage_map_btf_id[];
diff --git a/include/net/smc.h b/include/net/smc.h
index 597cb93..912c269 100644
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -11,13 +11,16 @@
 #ifndef _SMC_H
 #define _SMC_H
 
+#include <net/inet_connection_sock.h>
 #include <linux/device.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>
 #include <linux/wait.h>
+#include <linux/bpf.h>
 #include "linux/ism.h"
 
 struct sock;
+struct smc_diag_conninfo;
 
 #define SMC_MAX_PNETID_LEN	16	/* Max. length of PNET id */
 
@@ -90,4 +93,255 @@ struct smcd_dev {
 	u8 going_away : 1;
 };
 
+#if IS_ENABLED(CONFIG_SMC)
+
+struct smc_wr_rx_hdr {	/* common prefix part of LLC and CDC to demultiplex */
+	union {
+		u8 type;
+#if defined(__BIG_ENDIAN_BITFIELD)
+		struct {
+			u8 llc_version:4,
+			   llc_type:4;
+		};
+#elif defined(__LITTLE_ENDIAN_BITFIELD)
+		struct {
+			u8 llc_type:4,
+			   llc_version:4;
+		};
+#endif
+	};
+} __aligned(1);
+
+struct smc_cdc_conn_state_flags {
+#if defined(__BIG_ENDIAN_BITFIELD)
+	u8	peer_done_writing : 1;	/* Sending done indicator */
+	u8	peer_conn_closed : 1;	/* Peer connection closed indicator */
+	u8	peer_conn_abort : 1;	/* Abnormal close indicator */
+	u8	reserved : 5;
+#elif defined(__LITTLE_ENDIAN_BITFIELD)
+	u8	reserved : 5;
+	u8	peer_conn_abort : 1;
+	u8	peer_conn_closed : 1;
+	u8	peer_done_writing : 1;
+#endif
+};
+
+struct smc_cdc_producer_flags {
+#if defined(__BIG_ENDIAN_BITFIELD)
+	u8	write_blocked : 1;	/* Writing Blocked, no rx buf space */
+	u8	urg_data_pending : 1;	/* Urgent Data Pending */
+	u8	urg_data_present : 1;	/* Urgent Data Present */
+	u8	cons_curs_upd_req : 1;	/* cursor update requested */
+	u8	failover_validation : 1;/* message replay due to failover */
+	u8	reserved : 3;
+#elif defined(__LITTLE_ENDIAN_BITFIELD)
+	u8	reserved : 3;
+	u8	failover_validation : 1;
+	u8	cons_curs_upd_req : 1;
+	u8	urg_data_present : 1;
+	u8	urg_data_pending : 1;
+	u8	write_blocked : 1;
+#endif
+};
+
+enum smc_urg_state {
+	SMC_URG_VALID	= 1,			/* data present */
+	SMC_URG_NOTYET	= 2,			/* data pending */
+	SMC_URG_READ	= 3,			/* data was already read */
+};
+
+/* in host byte order */
+union smc_host_cursor {	/* SMC cursor - an offset in an RMBE */
+	struct {
+		u16	reserved;
+		u16	wrap;		/* window wrap sequence number */
+		u32	count;		/* cursor (= offset) part */
+	};
+#ifdef ATOMIC64_INIT
+	atomic64_t		acurs;	/* for atomic processing */
+#else
+	u64			acurs;	/* for atomic processing */
+#endif
+} __aligned(8);
+
+/* in host byte order, except for flag bitfields in network byte order */
+struct smc_host_cdc_msg {		/* Connection Data Control message */
+	struct smc_wr_rx_hdr		common; /* .type = 0xFE */
+	u8				len;	/* length = 44 */
+	u16				seqno;	/* connection seq # */
+	u32				token;	/* alert_token */
+	union smc_host_cursor		prod;		/* producer cursor */
+	union smc_host_cursor		cons;		/* consumer cursor,
+							 * piggy backed "ack"
+							 */
+	struct smc_cdc_producer_flags	prod_flags;	/* conn. tx/rx status */
+	struct smc_cdc_conn_state_flags	conn_state_flags; /* peer conn. status*/
+	u8				reserved[18];
+} __aligned(8);
+
+struct smc_connection {
+	struct rb_node		alert_node;
+	struct smc_link_group	*lgr;		/* link group of connection */
+	struct smc_link		*lnk;		/* assigned SMC-R link */
+	u32			alert_token_local; /* unique conn. id */
+	u8			peer_rmbe_idx;	/* from tcp handshake */
+	int			peer_rmbe_size;	/* size of peer rx buffer */
+	atomic_t		peer_rmbe_space;/* remaining free bytes in peer
+						 * rmbe
+						 */
+	int			rtoken_idx;	/* idx to peer RMB rkey/addr */
+
+	struct smc_buf_desc	*sndbuf_desc;	/* send buffer descriptor */
+	struct smc_buf_desc	*rmb_desc;	/* RMBE descriptor */
+	int			rmbe_size_short;/* compressed notation */
+	int			rmbe_update_limit;
+						/* lower limit for consumer
+						 * cursor update
+						 */
+
+	struct smc_host_cdc_msg	local_tx_ctrl;	/* host byte order staging
+						 * buffer for CDC msg send
+						 * .prod cf. TCP snd_nxt
+						 * .cons cf. TCP sends ack
+						 */
+	union smc_host_cursor	local_tx_ctrl_fin;
+						/* prod crsr - confirmed by peer
+						 */
+	union smc_host_cursor	tx_curs_prep;	/* tx - prepared data
+						 * snd_max..wmem_alloc
+						 */
+	union smc_host_cursor	tx_curs_sent;	/* tx - sent data
+						 * snd_nxt ?
+						 */
+	union smc_host_cursor	tx_curs_fin;	/* tx - confirmed by peer
+						 * snd-wnd-begin ?
+						 */
+	atomic_t		sndbuf_space;	/* remaining space in sndbuf */
+	u16			tx_cdc_seq;	/* sequence # for CDC send */
+	u16			tx_cdc_seq_fin;	/* sequence # - tx completed */
+	spinlock_t		send_lock;	/* protect wr_sends */
+	atomic_t		cdc_pend_tx_wr; /* number of pending tx CDC wqe
+						 * - inc when post wqe,
+						 * - dec on polled tx cqe
+						 */
+	wait_queue_head_t	cdc_pend_tx_wq; /* wakeup on no cdc_pend_tx_wr*/
+	atomic_t		tx_pushing;     /* nr_threads trying tx push */
+	struct delayed_work	tx_work;	/* retry of smc_cdc_msg_send */
+	u32			tx_off;		/* base offset in peer rmb */
+
+	struct smc_host_cdc_msg	local_rx_ctrl;	/* filled during event_handl.
+						 * .prod cf. TCP rcv_nxt
+						 * .cons cf. TCP snd_una
+						 */
+	union smc_host_cursor	rx_curs_confirmed; /* confirmed to peer
+						    * source of snd_una ?
+						    */
+	union smc_host_cursor	urg_curs;	/* points at urgent byte */
+	enum smc_urg_state	urg_state;
+	bool			urg_tx_pend;	/* urgent data staged */
+	bool			urg_rx_skip_pend;
+						/* indicate urgent oob data
+						 * read, but previous regular
+						 * data still pending
+						 */
+	char			urg_rx_byte;	/* urgent byte */
+	bool			tx_in_release_sock;
+						/* flush pending tx data in
+						 * sock release_cb()
+						 */
+	atomic_t		bytes_to_rcv;	/* arrived data,
+						 * not yet received
+						 */
+	atomic_t		splice_pending;	/* number of spliced bytes
+						 * pending processing
+						 */
+#ifndef KERNEL_HAS_ATOMIC64
+	spinlock_t		acurs_lock;	/* protect cursors */
+#endif
+	struct work_struct	close_work;	/* peer sent some closing */
+	struct work_struct	abort_work;	/* abort the connection */
+	struct tasklet_struct	rx_tsklet;	/* Receiver tasklet for SMC-D */
+	u8			rx_off;		/* receive offset:
+						 * 0 for SMC-R, 32 for SMC-D
+						 */
+	u64			peer_token;	/* SMC-D token of peer */
+	u8			killed : 1;	/* abnormal termination */
+	u8			freed : 1;	/* normal termiation */
+	u8			out_of_sync : 1; /* out of sync with peer */
+};
+
+struct smc_sock {				/* smc sock container */
+	struct sock		sk;
+	struct socket		*clcsock;	/* internal tcp socket */
+	void			(*clcsk_state_change)(struct sock *sk);
+						/* original stat_change fct. */
+	void			(*clcsk_data_ready)(struct sock *sk);
+						/* original data_ready fct. */
+	void			(*clcsk_write_space)(struct sock *sk);
+						/* original write_space fct. */
+	void			(*clcsk_error_report)(struct sock *sk);
+						/* original error_report fct. */
+	struct smc_connection	conn;		/* smc connection */
+	struct smc_sock		*listen_smc;	/* listen parent */
+	struct work_struct	connect_work;	/* handle non-blocking connect*/
+	struct work_struct	tcp_listen_work;/* handle tcp socket accepts */
+	struct work_struct	smc_listen_work;/* prepare new accept socket */
+	struct list_head	accept_q;	/* sockets to be accepted */
+	spinlock_t		accept_q_lock;	/* protects accept_q */
+	bool			limit_smc_hs;	/* put constraint on handshake */
+	bool			use_fallback;	/* fallback to tcp */
+	int			fallback_rsn;	/* reason for fallback */
+	u32			peer_diagnosis; /* decline reason from peer */
+	atomic_t                queued_smc_hs;  /* queued smc handshakes */
+	struct inet_connection_sock_af_ops		af_ops;
+	const struct inet_connection_sock_af_ops	*ori_af_ops;
+						/* original af ops */
+	int			sockopt_defer_accept;
+						/* sockopt TCP_DEFER_ACCEPT
+						 * value
+						 */
+	u8			wait_close_tx_prepared : 1;
+						/* shutdown wr or close
+						 * started, waiting for unsent
+						 * data to be sent
+						 */
+	u8			connect_nonblock : 1;
+						/* non-blocking connect in
+						 * flight
+						 */
+	struct mutex            clcsock_release_lock;
+						/* protects clcsock of a listen
+						 * socket
+						 */
+};
+
+#define SMC_SOCK_CLOSED_TIMING	(0)
+
+/* BPF struct ops for smc protocol negotiator */
+struct smc_sock_negotiator_ops {
+	/* ret for negotiate */
+	int (*negotiate)(struct smc_sock *sk);
+
+	/* info gathering timing */
+	void (*collect_info)(struct smc_sock *sk, int timing);
+};
+
+/* Query if current sock should go with SMC protocol
+ * SK_PASS for yes, otherwise for no.
+ */
+int smc_sock_should_select_smc(const struct smc_sock *smc);
+
+/* At some specific points in time,
+ * let negotiator can perform info gathering
+ * on target sock.
+ */
+void smc_sock_perform_collecting_info(const struct smc_sock *smc, int timing);
+
+#else
+struct smc_sock {};
+struct smc_connection {};
+struct smc_sock_negotiator_ops {};
+union smc_host_cursor {};
+#endif /* CONFIG_SMC */
+
 #endif	/* _SMC_H */
diff --git a/kernel/bpf/bpf_struct_ops_types.h b/kernel/bpf/bpf_struct_ops_types.h
index 5678a9d..35cdd15 100644
--- a/kernel/bpf/bpf_struct_ops_types.h
+++ b/kernel/bpf/bpf_struct_ops_types.h
@@ -9,4 +9,8 @@
 #include <net/tcp.h>
 BPF_STRUCT_OPS_TYPE(tcp_congestion_ops)
 #endif
+#if IS_ENABLED(CONFIG_SMC)
+#include <net/smc.h>
+BPF_STRUCT_OPS_TYPE(smc_sock_negotiator_ops)
+#endif
 #endif
diff --git a/net/Makefile b/net/Makefile
index 0914bea..47a4c00 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -52,6 +52,11 @@ obj-$(CONFIG_TIPC)		+= tipc/
 obj-$(CONFIG_NETLABEL)		+= netlabel/
 obj-$(CONFIG_IUCV)		+= iucv/
 obj-$(CONFIG_SMC)		+= smc/
+ifneq ($(CONFIG_SMC),)
+ifeq ($(CONFIG_BPF_SYSCALL),y)
+obj-y				+= smc/bpf_smc_struct_ops.o
+endif
+endif
 obj-$(CONFIG_RFKILL)		+= rfkill/
 obj-$(CONFIG_NET_9P)		+= 9p/
 obj-$(CONFIG_CAIF)		+= caif/
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index d7a7420..98651b85 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -166,6 +166,9 @@ static bool smc_hs_congested(const struct sock *sk)
 	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
 		return true;
 
+	if (!smc_sock_should_select_smc(smc))
+		return true;
+
 	return false;
 }
 
@@ -320,6 +323,9 @@ static int smc_release(struct socket *sock)
 	sock_hold(sk); /* sock_put below */
 	smc = smc_sk(sk);
 
+	/* trigger info gathering if needed.*/
+	smc_sock_perform_collecting_info(smc, SMC_SOCK_CLOSED_TIMING);
+
 	old_state = sk->sk_state;
 
 	/* cleanup for a dangling non-blocking connect */
@@ -1627,7 +1633,9 @@ static int smc_connect(struct socket *sock, struct sockaddr *addr,
 	}
 
 	smc_copy_sock_settings_to_clc(smc);
-	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
+	tcp_sk(smc->clcsock->sk)->syn_smc = (smc_sock_should_select_smc(smc) == SK_PASS) ?
+		1 : 0;
+
 	if (smc->connect_nonblock) {
 		rc = -EALREADY;
 		goto out;
diff --git a/net/smc/bpf_smc_struct_ops.c b/net/smc/bpf_smc_struct_ops.c
new file mode 100644
index 0000000..a5989b6
--- /dev/null
+++ b/net/smc/bpf_smc_struct_ops.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kernel.h>
+#include <linux/bpf_verifier.h>
+#include <linux/btf_ids.h>
+#include <linux/bpf.h>
+#include <linux/btf.h>
+#include <net/sock.h>
+#include <net/smc.h>
+
+extern struct bpf_struct_ops smc_sock_negotiator_ops;
+
+DEFINE_RWLOCK(smc_sock_negotiator_ops_rwlock);
+struct smc_sock_negotiator_ops *negotiator;
+
+/* convert sk to smc_sock */
+static inline struct smc_sock *smc_sk(const struct sock *sk)
+{
+	return (struct smc_sock *)sk;
+}
+
+/* register ops */
+static inline void smc_reg_passive_sk_ops(struct smc_sock_negotiator_ops *ops)
+{
+	write_lock_bh(&smc_sock_negotiator_ops_rwlock);
+	negotiator = ops;
+	write_unlock_bh(&smc_sock_negotiator_ops_rwlock);
+}
+
+/* unregister ops */
+static inline void smc_unreg_passive_sk_ops(struct smc_sock_negotiator_ops *ops)
+{
+	write_lock_bh(&smc_sock_negotiator_ops_rwlock);
+	if (negotiator == ops)
+		negotiator = NULL;
+	write_unlock_bh(&smc_sock_negotiator_ops_rwlock);
+}
+
+int smc_sock_should_select_smc(const struct smc_sock *smc)
+{
+	int ret = SK_PASS;
+
+	read_lock_bh(&smc_sock_negotiator_ops_rwlock);
+	if (negotiator && negotiator->negotiate)
+		ret = negotiator->negotiate((struct smc_sock *)smc);
+	read_unlock_bh(&smc_sock_negotiator_ops_rwlock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(smc_sock_should_select_smc);
+
+void smc_sock_perform_collecting_info(const struct smc_sock *smc, int timing)
+{
+	read_lock_bh(&smc_sock_negotiator_ops_rwlock);
+	if (negotiator && negotiator->collect_info)
+		negotiator->collect_info((struct smc_sock *)smc, timing);
+	read_unlock_bh(&smc_sock_negotiator_ops_rwlock);
+}
+EXPORT_SYMBOL_GPL(smc_sock_perform_collecting_info);
+
+/* define global smc ID for smc_struct_ops */
+BTF_ID_LIST_GLOBAL(btf_smc_ids, MAX_BTF_SMC_TYPE)
+#define BTF_SMC_TYPE(name, type) BTF_ID(struct, type)
+BTF_SMC_TYPE_xxx
+#undef BTF_SMC_TYPE
+
+static int bpf_smc_passive_sk_init(struct btf *btf)
+{
+	return 0;
+}
+
+/* register ops by BPF */
+static int bpf_smc_passive_sk_ops_reg(void *kdata)
+{
+	struct smc_sock_negotiator_ops *ops = kdata;
+
+	/* at least one ops need implement */
+	if (!ops->negotiate || !ops->collect_info) {
+		pr_err("At least one ops need implement.\n");
+		return -EINVAL;
+	}
+
+	smc_reg_passive_sk_ops(ops);
+	/* always success now */
+	return 0;
+}
+
+/* unregister ops by BPF */
+static void bpf_smc_passive_sk_ops_unreg(void *kdata)
+{
+	smc_unreg_passive_sk_ops(kdata);
+}
+
+static int bpf_smc_passive_sk_ops_check_member(const struct btf_type *t,
+					       const struct btf_member *member,
+					       const struct bpf_prog *prog)
+{
+	return 0;
+}
+
+static int bpf_smc_passive_sk_ops_init_member(const struct btf_type *t,
+					      const struct btf_member *member,
+					      void *kdata, const void *udata)
+{
+	return 0;
+}
+
+static const struct bpf_func_proto *
+smc_passive_sk_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+	return bpf_base_func_proto(func_id);
+}
+
+static bool smc_passive_sk_ops_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+						    const struct bpf_prog *prog,
+						    struct bpf_insn_access_aux *info)
+{
+	return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
+}
+
+static int smc_passive_sk_ops_prog_struct_access(struct bpf_verifier_log *log,
+						 const struct bpf_reg_state *reg,
+						 int off, int size, enum bpf_access_type atype,
+						 u32 *next_btf_id, enum bpf_type_flag *flag)
+{
+	/* only allow read now*/
+	if (atype == BPF_READ)
+		return btf_struct_access(log, reg, off, size, atype, next_btf_id, flag);
+
+	return -EACCES;
+}
+
+static const struct bpf_verifier_ops bpf_smc_passive_sk_verifier_ops = {
+	.get_func_proto  = smc_passive_sk_prog_func_proto,
+	.is_valid_access = smc_passive_sk_ops_prog_is_valid_access,
+	.btf_struct_access = smc_passive_sk_ops_prog_struct_access
+};
+
+struct bpf_struct_ops bpf_smc_sock_negotiator_ops = {
+	.verifier_ops = &bpf_smc_passive_sk_verifier_ops,
+	.init = bpf_smc_passive_sk_init,
+	.check_member = bpf_smc_passive_sk_ops_check_member,
+	.init_member = bpf_smc_passive_sk_ops_init_member,
+	.reg = bpf_smc_passive_sk_ops_reg,
+	.unreg = bpf_smc_passive_sk_ops_unreg,
+	.name = "smc_sock_negotiator_ops",
+};
diff --git a/net/smc/smc.h b/net/smc/smc.h
index 5ed765e..349b193 100644
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -57,232 +57,12 @@ enum smc_state {		/* possible states of an SMC socket */
 
 struct smc_link_group;
 
-struct smc_wr_rx_hdr {	/* common prefix part of LLC and CDC to demultiplex */
-	union {
-		u8 type;
-#if defined(__BIG_ENDIAN_BITFIELD)
-		struct {
-			u8 llc_version:4,
-			   llc_type:4;
-		};
-#elif defined(__LITTLE_ENDIAN_BITFIELD)
-		struct {
-			u8 llc_type:4,
-			   llc_version:4;
-		};
-#endif
-	};
-} __aligned(1);
-
-struct smc_cdc_conn_state_flags {
-#if defined(__BIG_ENDIAN_BITFIELD)
-	u8	peer_done_writing : 1;	/* Sending done indicator */
-	u8	peer_conn_closed : 1;	/* Peer connection closed indicator */
-	u8	peer_conn_abort : 1;	/* Abnormal close indicator */
-	u8	reserved : 5;
-#elif defined(__LITTLE_ENDIAN_BITFIELD)
-	u8	reserved : 5;
-	u8	peer_conn_abort : 1;
-	u8	peer_conn_closed : 1;
-	u8	peer_done_writing : 1;
-#endif
-};
-
-struct smc_cdc_producer_flags {
-#if defined(__BIG_ENDIAN_BITFIELD)
-	u8	write_blocked : 1;	/* Writing Blocked, no rx buf space */
-	u8	urg_data_pending : 1;	/* Urgent Data Pending */
-	u8	urg_data_present : 1;	/* Urgent Data Present */
-	u8	cons_curs_upd_req : 1;	/* cursor update requested */
-	u8	failover_validation : 1;/* message replay due to failover */
-	u8	reserved : 3;
-#elif defined(__LITTLE_ENDIAN_BITFIELD)
-	u8	reserved : 3;
-	u8	failover_validation : 1;
-	u8	cons_curs_upd_req : 1;
-	u8	urg_data_present : 1;
-	u8	urg_data_pending : 1;
-	u8	write_blocked : 1;
-#endif
-};
-
-/* in host byte order */
-union smc_host_cursor {	/* SMC cursor - an offset in an RMBE */
-	struct {
-		u16	reserved;
-		u16	wrap;		/* window wrap sequence number */
-		u32	count;		/* cursor (= offset) part */
-	};
-#ifdef KERNEL_HAS_ATOMIC64
-	atomic64_t		acurs;	/* for atomic processing */
-#else
-	u64			acurs;	/* for atomic processing */
-#endif
-} __aligned(8);
-
-/* in host byte order, except for flag bitfields in network byte order */
-struct smc_host_cdc_msg {		/* Connection Data Control message */
-	struct smc_wr_rx_hdr		common; /* .type = 0xFE */
-	u8				len;	/* length = 44 */
-	u16				seqno;	/* connection seq # */
-	u32				token;	/* alert_token */
-	union smc_host_cursor		prod;		/* producer cursor */
-	union smc_host_cursor		cons;		/* consumer cursor,
-							 * piggy backed "ack"
-							 */
-	struct smc_cdc_producer_flags	prod_flags;	/* conn. tx/rx status */
-	struct smc_cdc_conn_state_flags	conn_state_flags; /* peer conn. status*/
-	u8				reserved[18];
-} __aligned(8);
-
-enum smc_urg_state {
-	SMC_URG_VALID	= 1,			/* data present */
-	SMC_URG_NOTYET	= 2,			/* data pending */
-	SMC_URG_READ	= 3,			/* data was already read */
-};
-
 struct smc_mark_woken {
 	bool woken;
 	void *key;
 	wait_queue_entry_t wait_entry;
 };
 
-struct smc_connection {
-	struct rb_node		alert_node;
-	struct smc_link_group	*lgr;		/* link group of connection */
-	struct smc_link		*lnk;		/* assigned SMC-R link */
-	u32			alert_token_local; /* unique conn. id */
-	u8			peer_rmbe_idx;	/* from tcp handshake */
-	int			peer_rmbe_size;	/* size of peer rx buffer */
-	atomic_t		peer_rmbe_space;/* remaining free bytes in peer
-						 * rmbe
-						 */
-	int			rtoken_idx;	/* idx to peer RMB rkey/addr */
-
-	struct smc_buf_desc	*sndbuf_desc;	/* send buffer descriptor */
-	struct smc_buf_desc	*rmb_desc;	/* RMBE descriptor */
-	int			rmbe_size_short;/* compressed notation */
-	int			rmbe_update_limit;
-						/* lower limit for consumer
-						 * cursor update
-						 */
-
-	struct smc_host_cdc_msg	local_tx_ctrl;	/* host byte order staging
-						 * buffer for CDC msg send
-						 * .prod cf. TCP snd_nxt
-						 * .cons cf. TCP sends ack
-						 */
-	union smc_host_cursor	local_tx_ctrl_fin;
-						/* prod crsr - confirmed by peer
-						 */
-	union smc_host_cursor	tx_curs_prep;	/* tx - prepared data
-						 * snd_max..wmem_alloc
-						 */
-	union smc_host_cursor	tx_curs_sent;	/* tx - sent data
-						 * snd_nxt ?
-						 */
-	union smc_host_cursor	tx_curs_fin;	/* tx - confirmed by peer
-						 * snd-wnd-begin ?
-						 */
-	atomic_t		sndbuf_space;	/* remaining space in sndbuf */
-	u16			tx_cdc_seq;	/* sequence # for CDC send */
-	u16			tx_cdc_seq_fin;	/* sequence # - tx completed */
-	spinlock_t		send_lock;	/* protect wr_sends */
-	atomic_t		cdc_pend_tx_wr; /* number of pending tx CDC wqe
-						 * - inc when post wqe,
-						 * - dec on polled tx cqe
-						 */
-	wait_queue_head_t	cdc_pend_tx_wq; /* wakeup on no cdc_pend_tx_wr*/
-	atomic_t		tx_pushing;     /* nr_threads trying tx push */
-	struct delayed_work	tx_work;	/* retry of smc_cdc_msg_send */
-	u32			tx_off;		/* base offset in peer rmb */
-
-	struct smc_host_cdc_msg	local_rx_ctrl;	/* filled during event_handl.
-						 * .prod cf. TCP rcv_nxt
-						 * .cons cf. TCP snd_una
-						 */
-	union smc_host_cursor	rx_curs_confirmed; /* confirmed to peer
-						    * source of snd_una ?
-						    */
-	union smc_host_cursor	urg_curs;	/* points at urgent byte */
-	enum smc_urg_state	urg_state;
-	bool			urg_tx_pend;	/* urgent data staged */
-	bool			urg_rx_skip_pend;
-						/* indicate urgent oob data
-						 * read, but previous regular
-						 * data still pending
-						 */
-	char			urg_rx_byte;	/* urgent byte */
-	bool			tx_in_release_sock;
-						/* flush pending tx data in
-						 * sock release_cb()
-						 */
-	atomic_t		bytes_to_rcv;	/* arrived data,
-						 * not yet received
-						 */
-	atomic_t		splice_pending;	/* number of spliced bytes
-						 * pending processing
-						 */
-#ifndef KERNEL_HAS_ATOMIC64
-	spinlock_t		acurs_lock;	/* protect cursors */
-#endif
-	struct work_struct	close_work;	/* peer sent some closing */
-	struct work_struct	abort_work;	/* abort the connection */
-	struct tasklet_struct	rx_tsklet;	/* Receiver tasklet for SMC-D */
-	u8			rx_off;		/* receive offset:
-						 * 0 for SMC-R, 32 for SMC-D
-						 */
-	u64			peer_token;	/* SMC-D token of peer */
-	u8			killed : 1;	/* abnormal termination */
-	u8			freed : 1;	/* normal termiation */
-	u8			out_of_sync : 1; /* out of sync with peer */
-};
-
-struct smc_sock {				/* smc sock container */
-	struct sock		sk;
-	struct socket		*clcsock;	/* internal tcp socket */
-	void			(*clcsk_state_change)(struct sock *sk);
-						/* original stat_change fct. */
-	void			(*clcsk_data_ready)(struct sock *sk);
-						/* original data_ready fct. */
-	void			(*clcsk_write_space)(struct sock *sk);
-						/* original write_space fct. */
-	void			(*clcsk_error_report)(struct sock *sk);
-						/* original error_report fct. */
-	struct smc_connection	conn;		/* smc connection */
-	struct smc_sock		*listen_smc;	/* listen parent */
-	struct work_struct	connect_work;	/* handle non-blocking connect*/
-	struct work_struct	tcp_listen_work;/* handle tcp socket accepts */
-	struct work_struct	smc_listen_work;/* prepare new accept socket */
-	struct list_head	accept_q;	/* sockets to be accepted */
-	spinlock_t		accept_q_lock;	/* protects accept_q */
-	bool			limit_smc_hs;	/* put constraint on handshake */
-	bool			use_fallback;	/* fallback to tcp */
-	int			fallback_rsn;	/* reason for fallback */
-	u32			peer_diagnosis; /* decline reason from peer */
-	atomic_t                queued_smc_hs;  /* queued smc handshakes */
-	struct inet_connection_sock_af_ops		af_ops;
-	const struct inet_connection_sock_af_ops	*ori_af_ops;
-						/* original af ops */
-	int			sockopt_defer_accept;
-						/* sockopt TCP_DEFER_ACCEPT
-						 * value
-						 */
-	u8			wait_close_tx_prepared : 1;
-						/* shutdown wr or close
-						 * started, waiting for unsent
-						 * data to be sent
-						 */
-	u8			connect_nonblock : 1;
-						/* non-blocking connect in
-						 * flight
-						 */
-	struct mutex            clcsock_release_lock;
-						/* protects clcsock of a listen
-						 * socket
-						 * */
-};
-
 static inline struct smc_sock *smc_sk(const struct sock *sk)
 {
 	return (struct smc_sock *)sk;
