rdma/siw: connection management

Broken up commit to add the Soft iWarp RDMA driver.
Signed-off-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/sw/siw/siw_cm.h

+/* 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