[mirror_ubuntu-artful-kernel.git] / net / smc / smc_cdc.c

/*
 * Shared Memory Communications over RDMA (SMC-R) and RoCE
 *
 * Connection Data Control (CDC)
 * handles flow control
 *
 * Copyright IBM Corp. 2016
 *
 * Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
 */

#include <linux/spinlock.h>

#include "smc.h"
#include "smc_wr.h"
#include "smc_cdc.h"
#include "smc_tx.h"
#include "smc_rx.h"
#include "smc_close.h"

/********************************** send *************************************/

struct smc_cdc_tx_pend {
	struct smc_connection	*conn;		/* socket connection */
	union smc_host_cursor	cursor;	/* tx sndbuf cursor sent */
	union smc_host_cursor	p_cursor;	/* rx RMBE cursor produced */
	u16			ctrl_seq;	/* conn. tx sequence # */
};

/* handler for send/transmission completion of a CDC msg */
static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd,
			       struct smc_link *link,
			       enum ib_wc_status wc_status)
{
	struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend *)pnd_snd;
	struct smc_sock *smc;
	int diff;

	if (!cdcpend->conn)
		/* already dismissed */
		return;

	smc = container_of(cdcpend->conn, struct smc_sock, conn);
	bh_lock_sock(&smc->sk);
	if (!wc_status) {
		diff = smc_curs_diff(cdcpend->conn->sndbuf_size,
				     &cdcpend->conn->tx_curs_fin,
				     &cdcpend->cursor);
		/* sndbuf_space is decreased in smc_sendmsg */
		smp_mb__before_atomic();
		atomic_add(diff, &cdcpend->conn->sndbuf_space);
		/* guarantee 0 <= sndbuf_space <= sndbuf_size */
		smp_mb__after_atomic();
		smc_curs_write(&cdcpend->conn->tx_curs_fin,
			       smc_curs_read(&cdcpend->cursor, cdcpend->conn),
			       cdcpend->conn);
	}
	smc_tx_sndbuf_nonfull(smc);
	if (smc->sk.sk_state != SMC_ACTIVE)
		/* wake up smc_close_wait_tx_pends() */
		smc->sk.sk_state_change(&smc->sk);
	bh_unlock_sock(&smc->sk);
}

int smc_cdc_get_free_slot(struct smc_link *link,
			  struct smc_wr_buf **wr_buf,
			  struct smc_cdc_tx_pend **pend)
{
	return smc_wr_tx_get_free_slot(link, smc_cdc_tx_handler, wr_buf,
				       (struct smc_wr_tx_pend_priv **)pend);
}

static inline void smc_cdc_add_pending_send(struct smc_connection *conn,
					    struct smc_cdc_tx_pend *pend)
{
	BUILD_BUG_ON_MSG(
		sizeof(struct smc_cdc_msg) > SMC_WR_BUF_SIZE,
		"must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_cdc_msg)");
	BUILD_BUG_ON_MSG(
		offsetof(struct smc_cdc_msg, reserved) > SMC_WR_TX_SIZE,
		"must adapt SMC_WR_TX_SIZE to sizeof(struct smc_cdc_msg); if not all smc_wr upper layer protocols use the same message size any more, must start to set link->wr_tx_sges[i].length on each individual smc_wr_tx_send()");
	BUILD_BUG_ON_MSG(
		sizeof(struct smc_cdc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE,
		"must increase SMC_WR_TX_PEND_PRIV_SIZE to at least sizeof(struct smc_cdc_tx_pend)");
	pend->conn = conn;
	pend->cursor = conn->tx_curs_sent;
	pend->p_cursor = conn->local_tx_ctrl.prod;
	pend->ctrl_seq = conn->tx_cdc_seq;
}

int smc_cdc_msg_send(struct smc_connection *conn,
		     struct smc_wr_buf *wr_buf,
		     struct smc_cdc_tx_pend *pend)
{
	struct smc_link *link;
	int rc;

	link = &conn->lgr->lnk[SMC_SINGLE_LINK];

	smc_cdc_add_pending_send(conn, pend);

	conn->tx_cdc_seq++;
	conn->local_tx_ctrl.seqno = conn->tx_cdc_seq;
	smc_host_msg_to_cdc((struct smc_cdc_msg *)wr_buf,
			    &conn->local_tx_ctrl, conn);
	rc = smc_wr_tx_send(link, (struct smc_wr_tx_pend_priv *)pend);
	if (!rc)
		smc_curs_write(&conn->rx_curs_confirmed,
			       smc_curs_read(&conn->local_tx_ctrl.cons, conn),
			       conn);

	return rc;
}

int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
{
	struct smc_cdc_tx_pend *pend;
	struct smc_wr_buf *wr_buf;
	int rc;

	rc = smc_cdc_get_free_slot(&conn->lgr->lnk[SMC_SINGLE_LINK], &wr_buf,
				   &pend);
	if (rc)
		return rc;

	return smc_cdc_msg_send(conn, wr_buf, pend);
}

static bool smc_cdc_tx_filter(struct smc_wr_tx_pend_priv *tx_pend,
			      unsigned long data)
{
	struct smc_connection *conn = (struct smc_connection *)data;
	struct smc_cdc_tx_pend *cdc_pend =
		(struct smc_cdc_tx_pend *)tx_pend;

	return cdc_pend->conn == conn;
}

static void smc_cdc_tx_dismisser(struct smc_wr_tx_pend_priv *tx_pend)
{
	struct smc_cdc_tx_pend *cdc_pend =
		(struct smc_cdc_tx_pend *)tx_pend;

	cdc_pend->conn = NULL;
}

void smc_cdc_tx_dismiss_slots(struct smc_connection *conn)
{
	struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];

	smc_wr_tx_dismiss_slots(link, SMC_CDC_MSG_TYPE,
				smc_cdc_tx_filter, smc_cdc_tx_dismisser,
				(unsigned long)conn);
}

bool smc_cdc_tx_has_pending(struct smc_connection *conn)
{
	struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];

	return smc_wr_tx_has_pending(link, SMC_CDC_MSG_TYPE,
				     smc_cdc_tx_filter, (unsigned long)conn);
}

/********************************* receive ***********************************/

static inline bool smc_cdc_before(u16 seq1, u16 seq2)
{
	return (s16)(seq1 - seq2) < 0;
}

static void smc_cdc_msg_recv_action(struct smc_sock *smc,
				    struct smc_link *link,
				    struct smc_cdc_msg *cdc)
{
	union smc_host_cursor cons_old, prod_old;
	struct smc_connection *conn = &smc->conn;
	int diff_cons, diff_prod;

	if (!cdc->prod_flags.failover_validation) {
		if (smc_cdc_before(ntohs(cdc->seqno),
				   conn->local_rx_ctrl.seqno))
			/* received seqno is old */
			return;
	}
	smc_curs_write(&prod_old,
		       smc_curs_read(&conn->local_rx_ctrl.prod, conn),
		       conn);
	smc_curs_write(&cons_old,
		       smc_curs_read(&conn->local_rx_ctrl.cons, conn),
		       conn);
	smc_cdc_msg_to_host(&conn->local_rx_ctrl, cdc, conn);

	diff_cons = smc_curs_diff(conn->peer_rmbe_size, &cons_old,
				  &conn->local_rx_ctrl.cons);
	if (diff_cons) {
		/* peer_rmbe_space is decreased during data transfer with RDMA
		 * write
		 */
		smp_mb__before_atomic();
		atomic_add(diff_cons, &conn->peer_rmbe_space);
		/* guarantee 0 <= peer_rmbe_space <= peer_rmbe_size */
		smp_mb__after_atomic();
	}

	diff_prod = smc_curs_diff(conn->rmbe_size, &prod_old,
				  &conn->local_rx_ctrl.prod);
	if (diff_prod) {
		/* bytes_to_rcv is decreased in smc_recvmsg */
		smp_mb__before_atomic();
		atomic_add(diff_prod, &conn->bytes_to_rcv);
		/* guarantee 0 <= bytes_to_rcv <= rmbe_size */
		smp_mb__after_atomic();
		smc->sk.sk_data_ready(&smc->sk);
	}

	if (conn->local_rx_ctrl.conn_state_flags.peer_conn_abort) {
		smc->sk.sk_err = ECONNRESET;
		conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
	}
	if (smc_cdc_rxed_any_close_or_senddone(conn)) {
		smc->sk.sk_shutdown |= RCV_SHUTDOWN;
		if (smc->clcsock && smc->clcsock->sk)
			smc->clcsock->sk->sk_shutdown |= RCV_SHUTDOWN;
		sock_set_flag(&smc->sk, SOCK_DONE);
		schedule_work(&conn->close_work);
	}

	/* piggy backed tx info */
	/* trigger sndbuf consumer: RDMA write into peer RMBE and CDC */
	if (diff_cons && smc_tx_prepared_sends(conn)) {
		smc_tx_sndbuf_nonempty(conn);
		/* trigger socket release if connection closed */
		smc_close_wake_tx_prepared(smc);
	}

	/* socket connected but not accepted */
	if (!smc->sk.sk_socket)
		return;

	/* data available */
	if ((conn->local_rx_ctrl.prod_flags.write_blocked) ||
	    (conn->local_rx_ctrl.prod_flags.cons_curs_upd_req))
		smc_tx_consumer_update(conn);
}

/* called under tasklet context */
static inline void smc_cdc_msg_recv(struct smc_cdc_msg *cdc,
				    struct smc_link *link, u64 wr_id)
{
	struct smc_link_group *lgr = container_of(link, struct smc_link_group,
						  lnk[SMC_SINGLE_LINK]);
	struct smc_connection *connection;
	struct smc_sock *smc;

	/* lookup connection */
	read_lock_bh(&lgr->conns_lock);
	connection = smc_lgr_find_conn(ntohl(cdc->token), lgr);
	if (!connection) {
		read_unlock_bh(&lgr->conns_lock);
		return;
	}
	smc = container_of(connection, struct smc_sock, conn);
	sock_hold(&smc->sk);
	read_unlock_bh(&lgr->conns_lock);
	bh_lock_sock(&smc->sk);
	smc_cdc_msg_recv_action(smc, link, cdc);
	bh_unlock_sock(&smc->sk);
	sock_put(&smc->sk); /* no free sk in softirq-context */
}

/***************************** init, exit, misc ******************************/

static void smc_cdc_rx_handler(struct ib_wc *wc, void *buf)
{
	struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
	struct smc_cdc_msg *cdc = buf;

	if (wc->byte_len < offsetof(struct smc_cdc_msg, reserved))
		return; /* short message */
	if (cdc->len != sizeof(*cdc))
		return; /* invalid message */
	smc_cdc_msg_recv(cdc, link, wc->wr_id);
}

static struct smc_wr_rx_handler smc_cdc_rx_handlers[] = {
	{
		.handler	= smc_cdc_rx_handler,
		.type		= SMC_CDC_MSG_TYPE
	},
	{
		.handler	= NULL,
	}
};

int __init smc_cdc_init(void)
{
	struct smc_wr_rx_handler *handler;
	int rc = 0;

	for (handler = smc_cdc_rx_handlers; handler->handler; handler++) {
		INIT_HLIST_NODE(&handler->list);
		rc = smc_wr_rx_register_handler(handler);
		if (rc)
			break;
	}
	return rc;
}
Commit	Line	Data
5f08318f UB	1	/*
	2	* Shared Memory Communications over RDMA (SMC-R) and RoCE
	3	*
	4	* Connection Data Control (CDC)
	5	* handles flow control
	6	*
	7	* Copyright IBM Corp. 2016
	8	*
	9	* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
	10	*/
	11
	12	#include <linux/spinlock.h>
	13
	14	#include "smc.h"
	15	#include "smc_wr.h"
	16	#include "smc_cdc.h"
e6727f39	17	#include "smc_tx.h"
952310cc	18	#include "smc_rx.h"
b38d7324	19	#include "smc_close.h"
5f08318f UB	20
	21	/******************************** send ***********************************/
	22
	23	struct smc_cdc_tx_pend {
	24	struct smc_connection conn; / socket connection */
	25	union smc_host_cursor cursor; /* tx sndbuf cursor sent */
	26	union smc_host_cursor p_cursor; /* rx RMBE cursor produced */
	27	u16 ctrl_seq; /* conn. tx sequence # */
	28	};
	29
	30	/* handler for send/transmission completion of a CDC msg */
	31	static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd,
	32	struct smc_link *link,
	33	enum ib_wc_status wc_status)
	34	{
	35	struct smc_cdc_tx_pend cdcpend = (struct smc_cdc_tx_pend )pnd_snd;
	36	struct smc_sock *smc;
	37	int diff;
	38
	39	if (!cdcpend->conn)
	40	/* already dismissed */
	41	return;
	42
	43	smc = container_of(cdcpend->conn, struct smc_sock, conn);
	44	bh_lock_sock(&smc->sk);
	45	if (!wc_status) {
	46	diff = smc_curs_diff(cdcpend->conn->sndbuf_size,
	47	&cdcpend->conn->tx_curs_fin,
	48	&cdcpend->cursor);
	49	/* sndbuf_space is decreased in smc_sendmsg */
	50	smp_mb__before_atomic();
	51	atomic_add(diff, &cdcpend->conn->sndbuf_space);
	52	/* guarantee 0 <= sndbuf_space <= sndbuf_size */
	53	smp_mb__after_atomic();
	54	smc_curs_write(&cdcpend->conn->tx_curs_fin,
	55	smc_curs_read(&cdcpend->cursor, cdcpend->conn),
	56	cdcpend->conn);
	57	}
e6727f39	58	smc_tx_sndbuf_nonfull(smc);
b38d7324 UB	59	if (smc->sk.sk_state != SMC_ACTIVE)
	60	/* wake up smc_close_wait_tx_pends() */
	61	smc->sk.sk_state_change(&smc->sk);
5f08318f UB	62	bh_unlock_sock(&smc->sk);
	63	}
	64
	65	int smc_cdc_get_free_slot(struct smc_link *link,
	66	struct smc_wr_buf **wr_buf,
	67	struct smc_cdc_tx_pend **pend)
	68	{
	69	return smc_wr_tx_get_free_slot(link, smc_cdc_tx_handler, wr_buf,
	70	(struct smc_wr_tx_pend_priv **)pend);
	71	}
	72
	73	static inline void smc_cdc_add_pending_send(struct smc_connection *conn,
	74	struct smc_cdc_tx_pend *pend)
	75	{
	76	BUILD_BUG_ON_MSG(
	77	sizeof(struct smc_cdc_msg) > SMC_WR_BUF_SIZE,
	78	"must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_cdc_msg)");
	79	BUILD_BUG_ON_MSG(
	80	offsetof(struct smc_cdc_msg, reserved) > SMC_WR_TX_SIZE,
	81	"must adapt SMC_WR_TX_SIZE to sizeof(struct smc_cdc_msg); if not all smc_wr upper layer protocols use the same message size any more, must start to set link->wr_tx_sges[i].length on each individual smc_wr_tx_send()");
	82	BUILD_BUG_ON_MSG(
	83	sizeof(struct smc_cdc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE,
	84	"must increase SMC_WR_TX_PEND_PRIV_SIZE to at least sizeof(struct smc_cdc_tx_pend)");
	85	pend->conn = conn;
	86	pend->cursor = conn->tx_curs_sent;
	87	pend->p_cursor = conn->local_tx_ctrl.prod;
	88	pend->ctrl_seq = conn->tx_cdc_seq;
	89	}
	90
	91	int smc_cdc_msg_send(struct smc_connection *conn,
	92	struct smc_wr_buf *wr_buf,
	93	struct smc_cdc_tx_pend *pend)
	94	{
	95	struct smc_link *link;
	96	int rc;
	97
	98	link = &conn->lgr->lnk[SMC_SINGLE_LINK];
	99
	100	smc_cdc_add_pending_send(conn, pend);
	101
	102	conn->tx_cdc_seq++;
	103	conn->local_tx_ctrl.seqno = conn->tx_cdc_seq;
	104	smc_host_msg_to_cdc((struct smc_cdc_msg *)wr_buf,
	105	&conn->local_tx_ctrl, conn);
	106	rc = smc_wr_tx_send(link, (struct smc_wr_tx_pend_priv *)pend);
	107	if (!rc)
	108	smc_curs_write(&conn->rx_curs_confirmed,
	109	smc_curs_read(&conn->local_tx_ctrl.cons, conn),
	110	conn);
	111
	112	return rc;
	113	}
	114
	115	int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
	116	{
	117	struct smc_cdc_tx_pend *pend;
	118	struct smc_wr_buf *wr_buf;
	119	int rc;
	120
	121	rc = smc_cdc_get_free_slot(&conn->lgr->lnk[SMC_SINGLE_LINK], &wr_buf,
	122	&pend);
	123	if (rc)
	124	return rc;
	125
126	return smc_cdc_msg_send(conn, wr_buf, pend);
127	}
128
129	static bool smc_cdc_tx_filter(struct smc_wr_tx_pend_priv *tx_pend,
130	unsigned long data)
131	{
132	struct smc_connection conn = (struct smc_connection )data;
133	struct smc_cdc_tx_pend *cdc_pend =
134	(struct smc_cdc_tx_pend *)tx_pend;
135
136	return cdc_pend->conn == conn;
137	}
138
139	static void smc_cdc_tx_dismisser(struct smc_wr_tx_pend_priv *tx_pend)
140	{
141	struct smc_cdc_tx_pend *cdc_pend =
142	(struct smc_cdc_tx_pend *)tx_pend;
143
144	cdc_pend->conn = NULL;
145	}
146
147	void smc_cdc_tx_dismiss_slots(struct smc_connection *conn)
148	{
149	struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];
150
151	smc_wr_tx_dismiss_slots(link, SMC_CDC_MSG_TYPE,
152	smc_cdc_tx_filter, smc_cdc_tx_dismisser,
153	(unsigned long)conn);
154	}
155
b38d7324 UB	156	bool smc_cdc_tx_has_pending(struct smc_connection *conn)
	157	{
	158	struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];
	159
	160	return smc_wr_tx_has_pending(link, SMC_CDC_MSG_TYPE,
	161	smc_cdc_tx_filter, (unsigned long)conn);
	162	}
	163
5f08318f UB	164	/******************************* receive *********************************/
	165
	166	static inline bool smc_cdc_before(u16 seq1, u16 seq2)
	167	{
	168	return (s16)(seq1 - seq2) < 0;
	169	}
	170
	171	static void smc_cdc_msg_recv_action(struct smc_sock *smc,
	172	struct smc_link *link,
	173	struct smc_cdc_msg *cdc)
	174	{
	175	union smc_host_cursor cons_old, prod_old;
	176	struct smc_connection *conn = &smc->conn;
	177	int diff_cons, diff_prod;
	178
	179	if (!cdc->prod_flags.failover_validation) {
	180	if (smc_cdc_before(ntohs(cdc->seqno),
	181	conn->local_rx_ctrl.seqno))
	182	/* received seqno is old */
	183	return;
	184	}
	185	smc_curs_write(&prod_old,
	186	smc_curs_read(&conn->local_rx_ctrl.prod, conn),
	187	conn);
	188	smc_curs_write(&cons_old,
	189	smc_curs_read(&conn->local_rx_ctrl.cons, conn),
	190	conn);
	191	smc_cdc_msg_to_host(&conn->local_rx_ctrl, cdc, conn);
	192
	193	diff_cons = smc_curs_diff(conn->peer_rmbe_size, &cons_old,
	194	&conn->local_rx_ctrl.cons);
	195	if (diff_cons) {
	196	/* peer_rmbe_space is decreased during data transfer with RDMA
	197	* write
	198	*/
	199	smp_mb__before_atomic();
	200	atomic_add(diff_cons, &conn->peer_rmbe_space);
	201	/* guarantee 0 <= peer_rmbe_space <= peer_rmbe_size */
	202	smp_mb__after_atomic();
	203	}
	204
	205	diff_prod = smc_curs_diff(conn->rmbe_size, &prod_old,
	206	&conn->local_rx_ctrl.prod);
	207	if (diff_prod) {
	208	/* bytes_to_rcv is decreased in smc_recvmsg */
	209	smp_mb__before_atomic();
	210	atomic_add(diff_prod, &conn->bytes_to_rcv);
	211	/* guarantee 0 <= bytes_to_rcv <= rmbe_size */
	212	smp_mb__after_atomic();
952310cc	213	smc->sk.sk_data_ready(&smc->sk);
5f08318f UB	214	}
5f08318f UB	215
b38d7324	216	if (conn->local_rx_ctrl.conn_state_flags.peer_conn_abort) {
5f08318f	217	smc->sk.sk_err = ECONNRESET;
b38d7324 UB	218	conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
b38d7324 UB	219	}
46c28dbd UB	220	if (smc_cdc_rxed_any_close_or_senddone(conn)) {
	221	smc->sk.sk_shutdown \|= RCV_SHUTDOWN;
	222	if (smc->clcsock && smc->clcsock->sk)
	223	smc->clcsock->sk->sk_shutdown \|= RCV_SHUTDOWN;
	224	sock_set_flag(&smc->sk, SOCK_DONE);
	225	schedule_work(&conn->close_work);
	226	}
5f08318f UB	227
5f08318f UB	228	/* piggy backed tx info */
e6727f39	229	/* trigger sndbuf consumer: RDMA write into peer RMBE and CDC */
b38d7324	230	if (diff_cons && smc_tx_prepared_sends(conn)) {
e6727f39	231	smc_tx_sndbuf_nonempty(conn);
b38d7324 UB	232	/* trigger socket release if connection closed */
	233	smc_close_wake_tx_prepared(smc);
	234	}
5f08318f	235
5f08318f UB	236	/* socket connected but not accepted */
	237	if (!smc->sk.sk_socket)
	238	return;
	239
	240	/* data available */
952310cc UB	241	if ((conn->local_rx_ctrl.prod_flags.write_blocked) \|\|
	242	(conn->local_rx_ctrl.prod_flags.cons_curs_upd_req))
	243	smc_tx_consumer_update(conn);
5f08318f UB	244	}
	245
	246	/* called under tasklet context */
	247	static inline void smc_cdc_msg_recv(struct smc_cdc_msg *cdc,
	248	struct smc_link *link, u64 wr_id)
	249	{
	250	struct smc_link_group *lgr = container_of(link, struct smc_link_group,
	251	lnk[SMC_SINGLE_LINK]);
	252	struct smc_connection *connection;
	253	struct smc_sock *smc;
	254
	255	/* lookup connection */
	256	read_lock_bh(&lgr->conns_lock);
	257	connection = smc_lgr_find_conn(ntohl(cdc->token), lgr);
	258	if (!connection) {
	259	read_unlock_bh(&lgr->conns_lock);
	260	return;
	261	}
	262	smc = container_of(connection, struct smc_sock, conn);
	263	sock_hold(&smc->sk);
	264	read_unlock_bh(&lgr->conns_lock);
	265	bh_lock_sock(&smc->sk);
	266	smc_cdc_msg_recv_action(smc, link, cdc);
	267	bh_unlock_sock(&smc->sk);
	268	sock_put(&smc->sk); /* no free sk in softirq-context */
	269	}
	270
	271	/*************************** init, exit, misc ****************************/
	272
	273	static void smc_cdc_rx_handler(struct ib_wc wc, void buf)
	274	{
	275	struct smc_link link = (struct smc_link )wc->qp->qp_context;
	276	struct smc_cdc_msg *cdc = buf;
	277
	278	if (wc->byte_len < offsetof(struct smc_cdc_msg, reserved))
	279	return; /* short message */
	280	if (cdc->len != sizeof(*cdc))
	281	return; /* invalid message */
	282	smc_cdc_msg_recv(cdc, link, wc->wr_id);
	283	}
	284
	285	static struct smc_wr_rx_handler smc_cdc_rx_handlers[] = {
	286	{
	287	.handler = smc_cdc_rx_handler,
	288	.type = SMC_CDC_MSG_TYPE
	289	},
	290	{
	291	.handler = NULL,
	292	}
	293	};
	294
	295	int __init smc_cdc_init(void)
	296	{
	297	struct smc_wr_rx_handler *handler;
	298	int rc = 0;
	299
	300	for (handler = smc_cdc_rx_handlers; handler->handler; handler++) {
	301	INIT_HLIST_NODE(&handler->list);
	302	rc = smc_wr_rx_register_handler(handler);
	303	if (rc)
	304	break;
	305	}
	306	return rc;
	307	}