rdma/siw: connection management

/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */

/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */

/*          Greg Joyce <greg@opengridcomputing.com> */

/* Copyright (c) 2008-2019, IBM Corporation */

/* Copyright (c) 2017, Open Grid Computing, Inc. */

#ifndef _SIW_CM_H

#define _SIW_CM_H

#include <net/sock.h>

#include <linux/tcp.h>

#include <rdma/iw_cm.h>

enum siw_cep_state {

	SIW_EPSTATE_IDLE = 1,

	SIW_EPSTATE_LISTENING,

	SIW_EPSTATE_CONNECTING,

	SIW_EPSTATE_AWAIT_MPAREQ,

	SIW_EPSTATE_RECVD_MPAREQ,

	SIW_EPSTATE_AWAIT_MPAREP,

	SIW_EPSTATE_RDMA_MODE,

	SIW_EPSTATE_CLOSED

};

struct siw_mpa_info {

	struct mpa_rr hdr; /* peer mpa hdr in host byte order */

	struct mpa_v2_data v2_ctrl;

	struct mpa_v2_data v2_ctrl_req;

	char *pdata;

	int bytes_rcvd;

};

struct siw_device;

struct siw_cep {

	struct iw_cm_id *cm_id;

	struct siw_device *sdev;

	struct list_head devq;

	spinlock_t lock;

	struct kref ref;

	int in_use;

	wait_queue_head_t waitq;

	enum siw_cep_state state;

	struct list_head listenq;

	struct siw_cep *listen_cep;

	struct siw_qp *qp;

	struct socket *sock;

	struct siw_cm_work *mpa_timer;

	struct list_head work_freelist;

	struct siw_mpa_info mpa;

	int ord;

	int ird;

	bool enhanced_rdma_conn_est;

	/* Saved upcalls of socket */

	void (*sk_state_change)(struct sock *sk);

	void (*sk_data_ready)(struct sock *sk);

	void (*sk_write_space)(struct sock *sk);

	void (*sk_error_report)(struct sock *sk);

};

/*

 * Connection initiator waits 10 seconds to receive an

 * MPA reply after sending out MPA request. Reponder waits for

 * 5 seconds for MPA request to arrive if new TCP connection

 * was set up.

 */

#define MPAREQ_TIMEOUT (HZ * 10)

#define MPAREP_TIMEOUT (HZ * 5)

enum siw_work_type {

	SIW_CM_WORK_ACCEPT = 1,

	SIW_CM_WORK_READ_MPAHDR,

	SIW_CM_WORK_CLOSE_LLP, /* close socket */

	SIW_CM_WORK_PEER_CLOSE, /* socket indicated peer close */

	SIW_CM_WORK_MPATIMEOUT

};

struct siw_cm_work {

	struct delayed_work work;

	struct list_head list;

	enum siw_work_type type;

	struct siw_cep *cep;

};

#define to_sockaddr_in(a) (*(struct sockaddr_in *)(&(a)))

#define to_sockaddr_in6(a) (*(struct sockaddr_in6 *)(&(a)))

static inline int getname_peer(struct socket *s, struct sockaddr_storage *a)

{

	return s->ops->getname(s, (struct sockaddr *)a, 1);

}

static inline int getname_local(struct socket *s, struct sockaddr_storage *a)

{

	return s->ops->getname(s, (struct sockaddr *)a, 0);

}

static inline int ksock_recv(struct socket *sock, char *buf, size_t size,

			     int flags)

{

	struct kvec iov = { buf, size };

	struct msghdr msg = { .msg_name = NULL, .msg_flags = flags };

	return kernel_recvmsg(sock, &msg, &iov, 1, size, flags);

}

int siw_connect(struct iw_cm_id *id, struct iw_cm_conn_param *parm);

int siw_accept(struct iw_cm_id *id, struct iw_cm_conn_param *param);

int siw_reject(struct iw_cm_id *id, const void *data, u8 len);

int siw_create_listen(struct iw_cm_id *id, int backlog);

int siw_destroy_listen(struct iw_cm_id *id);

void siw_cep_get(struct siw_cep *cep);

void siw_cep_put(struct siw_cep *cep);

int siw_cm_queue_work(struct siw_cep *cep, enum siw_work_type type);

int siw_cm_init(void);

void siw_cm_exit(void);

/*

 * TCP socket interface

 */

#define sk_to_qp(sk) (((struct siw_cep *)((sk)->sk_user_data))->qp)

#define sk_to_cep(sk) ((struct siw_cep *)((sk)->sk_user_data))

#endif