rdma/siw: connection management
authorBernard Metzler <bmt@zurich.ibm.com>
Thu, 20 Jun 2019 16:21:26 +0000 (18:21 +0200)
committerJason Gunthorpe <jgg@mellanox.com>
Tue, 2 Jul 2019 20:03:40 +0000 (17:03 -0300)
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.c [new file with mode: 0644]
drivers/infiniband/sw/siw/siw_cm.h [new file with mode: 0644]

diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c
new file mode 100644 (file)
index 0000000..8e618cb
--- /dev/null
@@ -0,0 +1,2072 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/*          Fredy Neeser */
+/*          Greg Joyce <greg@opengridcomputing.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+/* Copyright (c) 2017, Open Grid Computing, Inc. */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/inetdevice.h>
+#include <net/addrconf.h>
+#include <linux/workqueue.h>
+#include <net/sock.h>
+#include <net/tcp.h>
+#include <linux/inet.h>
+#include <linux/tcp.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_user_verbs.h>
+
+#include "siw.h"
+#include "siw_cm.h"
+
+/*
+ * Set to any combination of
+ * MPA_V2_RDMA_NO_RTR, MPA_V2_RDMA_READ_RTR, MPA_V2_RDMA_WRITE_RTR
+ */
+static __be16 rtr_type = MPA_V2_RDMA_READ_RTR | MPA_V2_RDMA_WRITE_RTR;
+static const bool relaxed_ird_negotiation = 1;
+
+static void siw_cm_llp_state_change(struct sock *s);
+static void siw_cm_llp_data_ready(struct sock *s);
+static void siw_cm_llp_write_space(struct sock *s);
+static void siw_cm_llp_error_report(struct sock *s);
+static int siw_cm_upcall(struct siw_cep *cep, enum iw_cm_event_type reason,
+                        int status);
+
+static void siw_sk_assign_cm_upcalls(struct sock *sk)
+{
+       write_lock_bh(&sk->sk_callback_lock);
+       sk->sk_state_change = siw_cm_llp_state_change;
+       sk->sk_data_ready = siw_cm_llp_data_ready;
+       sk->sk_write_space = siw_cm_llp_write_space;
+       sk->sk_error_report = siw_cm_llp_error_report;
+       write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_sk_save_upcalls(struct sock *sk)
+{
+       struct siw_cep *cep = sk_to_cep(sk);
+
+       write_lock_bh(&sk->sk_callback_lock);
+       cep->sk_state_change = sk->sk_state_change;
+       cep->sk_data_ready = sk->sk_data_ready;
+       cep->sk_write_space = sk->sk_write_space;
+       cep->sk_error_report = sk->sk_error_report;
+       write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_sk_restore_upcalls(struct sock *sk, struct siw_cep *cep)
+{
+       sk->sk_state_change = cep->sk_state_change;
+       sk->sk_data_ready = cep->sk_data_ready;
+       sk->sk_write_space = cep->sk_write_space;
+       sk->sk_error_report = cep->sk_error_report;
+       sk->sk_user_data = NULL;
+}
+
+static void siw_qp_socket_assoc(struct siw_cep *cep, struct siw_qp *qp)
+{
+       struct socket *s = cep->sock;
+       struct sock *sk = s->sk;
+
+       write_lock_bh(&sk->sk_callback_lock);
+
+       qp->attrs.sk = s;
+       sk->sk_data_ready = siw_qp_llp_data_ready;
+       sk->sk_write_space = siw_qp_llp_write_space;
+
+       write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_socket_disassoc(struct socket *s)
+{
+       struct sock *sk = s->sk;
+       struct siw_cep *cep;
+
+       if (sk) {
+               write_lock_bh(&sk->sk_callback_lock);
+               cep = sk_to_cep(sk);
+               if (cep) {
+                       siw_sk_restore_upcalls(sk, cep);
+                       siw_cep_put(cep);
+               } else {
+                       pr_warn("siw: cannot restore sk callbacks: no ep\n");
+               }
+               write_unlock_bh(&sk->sk_callback_lock);
+       } else {
+               pr_warn("siw: cannot restore sk callbacks: no sk\n");
+       }
+}
+
+static void siw_rtr_data_ready(struct sock *sk)
+{
+       struct siw_cep *cep;
+       struct siw_qp *qp = NULL;
+       read_descriptor_t rd_desc;
+
+       read_lock(&sk->sk_callback_lock);
+
+       cep = sk_to_cep(sk);
+       if (!cep) {
+               WARN(1, "No connection endpoint\n");
+               goto out;
+       }
+       qp = sk_to_qp(sk);
+
+       memset(&rd_desc, 0, sizeof(rd_desc));
+       rd_desc.arg.data = qp;
+       rd_desc.count = 1;
+
+       tcp_read_sock(sk, &rd_desc, siw_tcp_rx_data);
+       /*
+        * Check if first frame was successfully processed.
+        * Signal connection full establishment if yes.
+        * Failed data processing would have already scheduled
+        * connection drop.
+        */
+       if (!qp->rx_stream.rx_suspend)
+               siw_cm_upcall(cep, IW_CM_EVENT_ESTABLISHED, 0);
+out:
+       read_unlock(&sk->sk_callback_lock);
+       if (qp)
+               siw_qp_socket_assoc(cep, qp);
+}
+
+static void siw_sk_assign_rtr_upcalls(struct siw_cep *cep)
+{
+       struct sock *sk = cep->sock->sk;
+
+       write_lock_bh(&sk->sk_callback_lock);
+       sk->sk_data_ready = siw_rtr_data_ready;
+       sk->sk_write_space = siw_qp_llp_write_space;
+       write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_cep_socket_assoc(struct siw_cep *cep, struct socket *s)
+{
+       cep->sock = s;
+       siw_cep_get(cep);
+       s->sk->sk_user_data = cep;
+
+       siw_sk_save_upcalls(s->sk);
+       siw_sk_assign_cm_upcalls(s->sk);
+}
+
+static struct siw_cep *siw_cep_alloc(struct siw_device *sdev)
+{
+       struct siw_cep *cep = kzalloc(sizeof(*cep), GFP_KERNEL);
+       unsigned long flags;
+
+       if (!cep)
+               return NULL;
+
+       INIT_LIST_HEAD(&cep->listenq);
+       INIT_LIST_HEAD(&cep->devq);
+       INIT_LIST_HEAD(&cep->work_freelist);
+
+       kref_init(&cep->ref);
+       cep->state = SIW_EPSTATE_IDLE;
+       init_waitqueue_head(&cep->waitq);
+       spin_lock_init(&cep->lock);
+       cep->sdev = sdev;
+       cep->enhanced_rdma_conn_est = false;
+
+       spin_lock_irqsave(&sdev->lock, flags);
+       list_add_tail(&cep->devq, &sdev->cep_list);
+       spin_unlock_irqrestore(&sdev->lock, flags);
+
+       siw_dbg_cep(cep, "new endpoint\n");
+       return cep;
+}
+
+static void siw_cm_free_work(struct siw_cep *cep)
+{
+       struct list_head *w, *tmp;
+       struct siw_cm_work *work;
+
+       list_for_each_safe(w, tmp, &cep->work_freelist) {
+               work = list_entry(w, struct siw_cm_work, list);
+               list_del(&work->list);
+               kfree(work);
+       }
+}
+
+static void siw_cancel_mpatimer(struct siw_cep *cep)
+{
+       spin_lock_bh(&cep->lock);
+       if (cep->mpa_timer) {
+               if (cancel_delayed_work(&cep->mpa_timer->work)) {
+                       siw_cep_put(cep);
+                       kfree(cep->mpa_timer); /* not needed again */
+               }
+               cep->mpa_timer = NULL;
+       }
+       spin_unlock_bh(&cep->lock);
+}
+
+static void siw_put_work(struct siw_cm_work *work)
+{
+       INIT_LIST_HEAD(&work->list);
+       spin_lock_bh(&work->cep->lock);
+       list_add(&work->list, &work->cep->work_freelist);
+       spin_unlock_bh(&work->cep->lock);
+}
+
+static void siw_cep_set_inuse(struct siw_cep *cep)
+{
+       unsigned long flags;
+       int rv;
+retry:
+       spin_lock_irqsave(&cep->lock, flags);
+
+       if (cep->in_use) {
+               spin_unlock_irqrestore(&cep->lock, flags);
+               rv = wait_event_interruptible(cep->waitq, !cep->in_use);
+               if (signal_pending(current))
+                       flush_signals(current);
+               goto retry;
+       } else {
+               cep->in_use = 1;
+               spin_unlock_irqrestore(&cep->lock, flags);
+       }
+}
+
+static void siw_cep_set_free(struct siw_cep *cep)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&cep->lock, flags);
+       cep->in_use = 0;
+       spin_unlock_irqrestore(&cep->lock, flags);
+
+       wake_up(&cep->waitq);
+}
+
+static void __siw_cep_dealloc(struct kref *ref)
+{
+       struct siw_cep *cep = container_of(ref, struct siw_cep, ref);
+       struct siw_device *sdev = cep->sdev;
+       unsigned long flags;
+
+       WARN_ON(cep->listen_cep);
+
+       /* kfree(NULL) is safe */
+       kfree(cep->mpa.pdata);
+       spin_lock_bh(&cep->lock);
+       if (!list_empty(&cep->work_freelist))
+               siw_cm_free_work(cep);
+       spin_unlock_bh(&cep->lock);
+
+       spin_lock_irqsave(&sdev->lock, flags);
+       list_del(&cep->devq);
+       spin_unlock_irqrestore(&sdev->lock, flags);
+
+       siw_dbg_cep(cep, "free endpoint\n");
+       kfree(cep);
+}
+
+static struct siw_cm_work *siw_get_work(struct siw_cep *cep)
+{
+       struct siw_cm_work *work = NULL;
+
+       spin_lock_bh(&cep->lock);
+       if (!list_empty(&cep->work_freelist)) {
+               work = list_entry(cep->work_freelist.next, struct siw_cm_work,
+                                 list);
+               list_del_init(&work->list);
+       }
+       spin_unlock_bh(&cep->lock);
+       return work;
+}
+
+static int siw_cm_alloc_work(struct siw_cep *cep, int num)
+{
+       struct siw_cm_work *work;
+
+       while (num--) {
+               work = kmalloc(sizeof(*work), GFP_KERNEL);
+               if (!work) {
+                       if (!(list_empty(&cep->work_freelist)))
+                               siw_cm_free_work(cep);
+                       return -ENOMEM;
+               }
+               work->cep = cep;
+               INIT_LIST_HEAD(&work->list);
+               list_add(&work->list, &cep->work_freelist);
+       }
+       return 0;
+}
+
+/*
+ * siw_cm_upcall()
+ *
+ * Upcall to IWCM to inform about async connection events
+ */
+static int siw_cm_upcall(struct siw_cep *cep, enum iw_cm_event_type reason,
+                        int status)
+{
+       struct iw_cm_event event;
+       struct iw_cm_id *id;
+
+       memset(&event, 0, sizeof(event));
+       event.status = status;
+       event.event = reason;
+
+       if (reason == IW_CM_EVENT_CONNECT_REQUEST) {
+               event.provider_data = cep;
+               id = cep->listen_cep->cm_id;
+       } else {
+               id = cep->cm_id;
+       }
+       /* Signal IRD and ORD */
+       if (reason == IW_CM_EVENT_ESTABLISHED ||
+           reason == IW_CM_EVENT_CONNECT_REPLY) {
+               /* Signal negotiated IRD/ORD values we will use */
+               event.ird = cep->ird;
+               event.ord = cep->ord;
+       } else if (reason == IW_CM_EVENT_CONNECT_REQUEST) {
+               event.ird = cep->ord;
+               event.ord = cep->ird;
+       }
+       /* Signal private data and address information */
+       if (reason == IW_CM_EVENT_CONNECT_REQUEST ||
+           reason == IW_CM_EVENT_CONNECT_REPLY) {
+               u16 pd_len = be16_to_cpu(cep->mpa.hdr.params.pd_len);
+
+               if (pd_len) {
+                       /*
+                        * hand over MPA private data
+                        */
+                       event.private_data_len = pd_len;
+                       event.private_data = cep->mpa.pdata;
+
+                       /* Hide MPA V2 IRD/ORD control */
+                       if (cep->enhanced_rdma_conn_est) {
+                               event.private_data_len -=
+                                       sizeof(struct mpa_v2_data);
+                               event.private_data +=
+                                       sizeof(struct mpa_v2_data);
+                       }
+               }
+               getname_local(cep->sock, &event.local_addr);
+               getname_peer(cep->sock, &event.remote_addr);
+       }
+       siw_dbg_cep(cep, "[QP %u]: id 0x%p, reason=%d, status=%d\n",
+                   cep->qp ? qp_id(cep->qp) : -1, id, reason, status);
+
+       return id->event_handler(id, &event);
+}
+
+/*
+ * siw_qp_cm_drop()
+ *
+ * Drops established LLP connection if present and not already
+ * scheduled for dropping. Called from user context, SQ workqueue
+ * or receive IRQ. Caller signals if socket can be immediately
+ * closed (basically, if not in IRQ).
+ */
+void siw_qp_cm_drop(struct siw_qp *qp, int schedule)
+{
+       struct siw_cep *cep = qp->cep;
+
+       qp->rx_stream.rx_suspend = 1;
+       qp->tx_ctx.tx_suspend = 1;
+
+       if (!qp->cep)
+               return;
+
+       if (schedule) {
+               siw_cm_queue_work(cep, SIW_CM_WORK_CLOSE_LLP);
+       } else {
+               siw_cep_set_inuse(cep);
+
+               if (cep->state == SIW_EPSTATE_CLOSED) {
+                       siw_dbg_cep(cep, "already closed\n");
+                       goto out;
+               }
+               siw_dbg_cep(cep, "immediate close, state %d\n", cep->state);
+
+               if (qp->term_info.valid)
+                       siw_send_terminate(qp);
+
+               if (cep->cm_id) {
+                       switch (cep->state) {
+                       case SIW_EPSTATE_AWAIT_MPAREP:
+                               siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+                                             -EINVAL);
+                               break;
+
+                       case SIW_EPSTATE_RDMA_MODE:
+                               siw_cm_upcall(cep, IW_CM_EVENT_CLOSE, 0);
+                               break;
+
+                       case SIW_EPSTATE_IDLE:
+                       case SIW_EPSTATE_LISTENING:
+                       case SIW_EPSTATE_CONNECTING:
+                       case SIW_EPSTATE_AWAIT_MPAREQ:
+                       case SIW_EPSTATE_RECVD_MPAREQ:
+                       case SIW_EPSTATE_CLOSED:
+                       default:
+                               break;
+                       }
+                       cep->cm_id->rem_ref(cep->cm_id);
+                       cep->cm_id = NULL;
+                       siw_cep_put(cep);
+               }
+               cep->state = SIW_EPSTATE_CLOSED;
+
+               if (cep->sock) {
+                       siw_socket_disassoc(cep->sock);
+                       /*
+                        * Immediately close socket
+                        */
+                       sock_release(cep->sock);
+                       cep->sock = NULL;
+               }
+               if (cep->qp) {
+                       cep->qp = NULL;
+                       siw_qp_put(qp);
+               }
+out:
+               siw_cep_set_free(cep);
+       }
+}
+
+void siw_cep_put(struct siw_cep *cep)
+{
+       WARN_ON(kref_read(&cep->ref) < 1);
+       kref_put(&cep->ref, __siw_cep_dealloc);
+}
+
+void siw_cep_get(struct siw_cep *cep)
+{
+       kref_get(&cep->ref);
+}
+
+/*
+ * Expects params->pd_len in host byte order
+ */
+static int siw_send_mpareqrep(struct siw_cep *cep, const void *pdata, u8 pd_len)
+{
+       struct socket *s = cep->sock;
+       struct mpa_rr *rr = &cep->mpa.hdr;
+       struct kvec iov[3];
+       struct msghdr msg;
+       int rv;
+       int iovec_num = 0;
+       int mpa_len;
+
+       memset(&msg, 0, sizeof(msg));
+
+       iov[iovec_num].iov_base = rr;
+       iov[iovec_num].iov_len = sizeof(*rr);
+       mpa_len = sizeof(*rr);
+
+       if (cep->enhanced_rdma_conn_est) {
+               iovec_num++;
+               iov[iovec_num].iov_base = &cep->mpa.v2_ctrl;
+               iov[iovec_num].iov_len = sizeof(cep->mpa.v2_ctrl);
+               mpa_len += sizeof(cep->mpa.v2_ctrl);
+       }
+       if (pd_len) {
+               iovec_num++;
+               iov[iovec_num].iov_base = (char *)pdata;
+               iov[iovec_num].iov_len = pd_len;
+               mpa_len += pd_len;
+       }
+       if (cep->enhanced_rdma_conn_est)
+               pd_len += sizeof(cep->mpa.v2_ctrl);
+
+       rr->params.pd_len = cpu_to_be16(pd_len);
+
+       rv = kernel_sendmsg(s, &msg, iov, iovec_num + 1, mpa_len);
+
+       return rv < 0 ? rv : 0;
+}
+
+/*
+ * Receive MPA Request/Reply header.
+ *
+ * Returns 0 if complete MPA Request/Reply header including
+ * eventual private data was received. Returns -EAGAIN if
+ * header was partially received or negative error code otherwise.
+ *
+ * Context: May be called in process context only
+ */
+static int siw_recv_mpa_rr(struct siw_cep *cep)
+{
+       struct mpa_rr *hdr = &cep->mpa.hdr;
+       struct socket *s = cep->sock;
+       u16 pd_len;
+       int rcvd, to_rcv;
+
+       if (cep->mpa.bytes_rcvd < sizeof(struct mpa_rr)) {
+               rcvd = ksock_recv(s, (char *)hdr + cep->mpa.bytes_rcvd,
+                                 sizeof(struct mpa_rr) - cep->mpa.bytes_rcvd,
+                                 0);
+               if (rcvd <= 0)
+                       return -ECONNABORTED;
+
+               cep->mpa.bytes_rcvd += rcvd;
+
+               if (cep->mpa.bytes_rcvd < sizeof(struct mpa_rr))
+                       return -EAGAIN;
+
+               if (be16_to_cpu(hdr->params.pd_len) > MPA_MAX_PRIVDATA)
+                       return -EPROTO;
+       }
+       pd_len = be16_to_cpu(hdr->params.pd_len);
+
+       /*
+        * At least the MPA Request/Reply header (frame not including
+        * private data) has been received.
+        * Receive (or continue receiving) any private data.
+        */
+       to_rcv = pd_len - (cep->mpa.bytes_rcvd - sizeof(struct mpa_rr));
+
+       if (!to_rcv) {
+               /*
+                * We must have hdr->params.pd_len == 0 and thus received a
+                * complete MPA Request/Reply frame.
+                * Check against peer protocol violation.
+                */
+               u32 word;
+
+               rcvd = ksock_recv(s, (char *)&word, sizeof(word), MSG_DONTWAIT);
+               if (rcvd == -EAGAIN)
+                       return 0;
+
+               if (rcvd == 0) {
+                       siw_dbg_cep(cep, "peer EOF\n");
+                       return -EPIPE;
+               }
+               if (rcvd < 0) {
+                       siw_dbg_cep(cep, "error: %d\n", rcvd);
+                       return rcvd;
+               }
+               siw_dbg_cep(cep, "peer sent extra data: %d\n", rcvd);
+
+               return -EPROTO;
+       }
+
+       /*
+        * At this point, we must have hdr->params.pd_len != 0.
+        * A private data buffer gets allocated if hdr->params.pd_len != 0.
+        */
+       if (!cep->mpa.pdata) {
+               cep->mpa.pdata = kmalloc(pd_len + 4, GFP_KERNEL);
+               if (!cep->mpa.pdata)
+                       return -ENOMEM;
+       }
+       rcvd = ksock_recv(
+               s, cep->mpa.pdata + cep->mpa.bytes_rcvd - sizeof(struct mpa_rr),
+               to_rcv + 4, MSG_DONTWAIT);
+
+       if (rcvd < 0)
+               return rcvd;
+
+       if (rcvd > to_rcv)
+               return -EPROTO;
+
+       cep->mpa.bytes_rcvd += rcvd;
+
+       if (to_rcv == rcvd) {
+               siw_dbg_cep(cep, "%d bytes private data received\n", pd_len);
+               return 0;
+       }
+       return -EAGAIN;
+}
+
+/*
+ * siw_proc_mpareq()
+ *
+ * Read MPA Request from socket and signal new connection to IWCM
+ * if success. Caller must hold lock on corresponding listening CEP.
+ */
+static int siw_proc_mpareq(struct siw_cep *cep)
+{
+       struct mpa_rr *req;
+       int version, rv;
+       u16 pd_len;
+
+       rv = siw_recv_mpa_rr(cep);
+       if (rv)
+               return rv;
+
+       req = &cep->mpa.hdr;
+
+       version = __mpa_rr_revision(req->params.bits);
+       pd_len = be16_to_cpu(req->params.pd_len);
+
+       if (version > MPA_REVISION_2)
+               /* allow for 0, 1, and 2 only */
+               return -EPROTO;
+
+       if (memcmp(req->key, MPA_KEY_REQ, 16))
+               return -EPROTO;
+
+       /* Prepare for sending MPA reply */
+       memcpy(req->key, MPA_KEY_REP, 16);
+
+       if (version == MPA_REVISION_2 &&
+           (req->params.bits & MPA_RR_FLAG_ENHANCED)) {
+               /*
+                * MPA version 2 must signal IRD/ORD values and P2P mode
+                * in private data if header flag MPA_RR_FLAG_ENHANCED
+                * is set.
+                */
+               if (pd_len < sizeof(struct mpa_v2_data))
+                       goto reject_conn;
+
+               cep->enhanced_rdma_conn_est = true;
+       }
+
+       /* MPA Markers: currently not supported. Marker TX to be added. */
+       if (req->params.bits & MPA_RR_FLAG_MARKERS)
+               goto reject_conn;
+
+       if (req->params.bits & MPA_RR_FLAG_CRC) {
+               /*
+                * RFC 5044, page 27: CRC MUST be used if peer requests it.
+                * siw specific: 'mpa_crc_strict' parameter to reject
+                * connection with CRC if local CRC off enforced by
+                * 'mpa_crc_strict' module parameter.
+                */
+               if (!mpa_crc_required && mpa_crc_strict)
+                       goto reject_conn;
+
+               /* Enable CRC if requested by module parameter */
+               if (mpa_crc_required)
+                       req->params.bits |= MPA_RR_FLAG_CRC;
+       }
+       if (cep->enhanced_rdma_conn_est) {
+               struct mpa_v2_data *v2 = (struct mpa_v2_data *)cep->mpa.pdata;
+
+               /*
+                * Peer requested ORD becomes requested local IRD,
+                * peer requested IRD becomes requested local ORD.
+                * IRD and ORD get limited by global maximum values.
+                */
+               cep->ord = ntohs(v2->ird) & MPA_IRD_ORD_MASK;
+               cep->ord = min(cep->ord, SIW_MAX_ORD_QP);
+               cep->ird = ntohs(v2->ord) & MPA_IRD_ORD_MASK;
+               cep->ird = min(cep->ird, SIW_MAX_IRD_QP);
+
+               /* May get overwritten by locally negotiated values */
+               cep->mpa.v2_ctrl.ird = htons(cep->ird);
+               cep->mpa.v2_ctrl.ord = htons(cep->ord);
+
+               /*
+                * Support for peer sent zero length Write or Read to
+                * let local side enter RTS. Writes are preferred.
+                * Sends would require pre-posting a Receive and are
+                * not supported.
+                * Propose zero length Write if none of Read and Write
+                * is indicated.
+                */
+               if (v2->ird & MPA_V2_PEER_TO_PEER) {
+                       cep->mpa.v2_ctrl.ird |= MPA_V2_PEER_TO_PEER;
+
+                       if (v2->ord & MPA_V2_RDMA_WRITE_RTR)
+                               cep->mpa.v2_ctrl.ord |= MPA_V2_RDMA_WRITE_RTR;
+                       else if (v2->ord & MPA_V2_RDMA_READ_RTR)
+                               cep->mpa.v2_ctrl.ord |= MPA_V2_RDMA_READ_RTR;
+                       else
+                               cep->mpa.v2_ctrl.ord |= MPA_V2_RDMA_WRITE_RTR;
+               }
+       }
+
+       cep->state = SIW_EPSTATE_RECVD_MPAREQ;
+
+       /* Keep reference until IWCM accepts/rejects */
+       siw_cep_get(cep);
+       rv = siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REQUEST, 0);
+       if (rv)
+               siw_cep_put(cep);
+
+       return rv;
+
+reject_conn:
+       siw_dbg_cep(cep, "reject: crc %d:%d:%d, m %d:%d\n",
+                   req->params.bits & MPA_RR_FLAG_CRC ? 1 : 0,
+                   mpa_crc_required, mpa_crc_strict,
+                   req->params.bits & MPA_RR_FLAG_MARKERS ? 1 : 0, 0);
+
+       req->params.bits &= ~MPA_RR_FLAG_MARKERS;
+       req->params.bits |= MPA_RR_FLAG_REJECT;
+
+       if (!mpa_crc_required && mpa_crc_strict)
+               req->params.bits &= ~MPA_RR_FLAG_CRC;
+
+       if (pd_len)
+               kfree(cep->mpa.pdata);
+
+       cep->mpa.pdata = NULL;
+
+       siw_send_mpareqrep(cep, NULL, 0);
+
+       return -EOPNOTSUPP;
+}
+
+static int siw_proc_mpareply(struct siw_cep *cep)
+{
+       struct siw_qp_attrs qp_attrs;
+       enum siw_qp_attr_mask qp_attr_mask;
+       struct siw_qp *qp = cep->qp;
+       struct mpa_rr *rep;
+       int rv;
+       u16 rep_ord;
+       u16 rep_ird;
+       bool ird_insufficient = false;
+       enum mpa_v2_ctrl mpa_p2p_mode = MPA_V2_RDMA_NO_RTR;
+
+       rv = siw_recv_mpa_rr(cep);
+       if (rv != -EAGAIN)
+               siw_cancel_mpatimer(cep);
+       if (rv)
+               goto out_err;
+
+       rep = &cep->mpa.hdr;
+
+       if (__mpa_rr_revision(rep->params.bits) > MPA_REVISION_2) {
+               /* allow for 0, 1,  and 2 only */
+               rv = -EPROTO;
+               goto out_err;
+       }
+       if (memcmp(rep->key, MPA_KEY_REP, 16)) {
+               siw_init_terminate(qp, TERM_ERROR_LAYER_LLP, LLP_ETYPE_MPA,
+                                  LLP_ECODE_INVALID_REQ_RESP, 0);
+               siw_send_terminate(qp);
+               rv = -EPROTO;
+               goto out_err;
+       }
+       if (rep->params.bits & MPA_RR_FLAG_REJECT) {
+               siw_dbg_cep(cep, "got mpa reject\n");
+               siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, -ECONNRESET);
+
+               return -ECONNRESET;
+       }
+       if (try_gso && rep->params.bits & MPA_RR_FLAG_GSO_EXP) {
+               siw_dbg_cep(cep, "peer allows GSO on TX\n");
+               qp->tx_ctx.gso_seg_limit = 0;
+       }
+       if ((rep->params.bits & MPA_RR_FLAG_MARKERS) ||
+           (mpa_crc_required && !(rep->params.bits & MPA_RR_FLAG_CRC)) ||
+           (mpa_crc_strict && !mpa_crc_required &&
+            (rep->params.bits & MPA_RR_FLAG_CRC))) {
+               siw_dbg_cep(cep, "reply unsupp: crc %d:%d:%d, m %d:%d\n",
+                           rep->params.bits & MPA_RR_FLAG_CRC ? 1 : 0,
+                           mpa_crc_required, mpa_crc_strict,
+                           rep->params.bits & MPA_RR_FLAG_MARKERS ? 1 : 0, 0);
+
+               siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, -ECONNREFUSED);
+
+               return -EINVAL;
+       }
+       if (cep->enhanced_rdma_conn_est) {
+               struct mpa_v2_data *v2;
+
+               if (__mpa_rr_revision(rep->params.bits) < MPA_REVISION_2 ||
+                   !(rep->params.bits & MPA_RR_FLAG_ENHANCED)) {
+                       /*
+                        * Protocol failure: The responder MUST reply with
+                        * MPA version 2 and MUST set MPA_RR_FLAG_ENHANCED.
+                        */
+                       siw_dbg_cep(cep, "mpa reply error: vers %d, enhcd %d\n",
+                                   __mpa_rr_revision(rep->params.bits),
+                                   rep->params.bits & MPA_RR_FLAG_ENHANCED ?
+                                           1 :
+                                           0);
+
+                       siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+                                     -ECONNRESET);
+                       return -EINVAL;
+               }
+               v2 = (struct mpa_v2_data *)cep->mpa.pdata;
+               rep_ird = ntohs(v2->ird) & MPA_IRD_ORD_MASK;
+               rep_ord = ntohs(v2->ord) & MPA_IRD_ORD_MASK;
+
+               if (cep->ird < rep_ord &&
+                   (relaxed_ird_negotiation == false ||
+                    rep_ord > cep->sdev->attrs.max_ird)) {
+                       siw_dbg_cep(cep, "ird %d, rep_ord %d, max_ord %d\n",
+                                   cep->ird, rep_ord,
+                                   cep->sdev->attrs.max_ord);
+                       ird_insufficient = true;
+               }
+               if (cep->ord > rep_ird && relaxed_ird_negotiation == false) {
+                       siw_dbg_cep(cep, "ord %d, rep_ird %d\n", cep->ord,
+                                   rep_ird);
+                       ird_insufficient = true;
+               }
+               /*
+                * Always report negotiated peer values to user,
+                * even if IRD/ORD negotiation failed
+                */
+               cep->ird = rep_ord;
+               cep->ord = rep_ird;
+
+               if (ird_insufficient) {
+                       /*
+                        * If the initiator IRD is insuffient for the
+                        * responder ORD, send a TERM.
+                        */
+                       siw_init_terminate(qp, TERM_ERROR_LAYER_LLP,
+                                          LLP_ETYPE_MPA,
+                                          LLP_ECODE_INSUFFICIENT_IRD, 0);
+                       siw_send_terminate(qp);
+                       rv = -ENOMEM;
+                       goto out_err;
+               }
+               if (cep->mpa.v2_ctrl_req.ird & MPA_V2_PEER_TO_PEER)
+                       mpa_p2p_mode =
+                               cep->mpa.v2_ctrl_req.ord &
+                               (MPA_V2_RDMA_WRITE_RTR | MPA_V2_RDMA_READ_RTR);
+
+               /*
+                * Check if we requested P2P mode, and if peer agrees
+                */
+               if (mpa_p2p_mode != MPA_V2_RDMA_NO_RTR) {
+                       if ((mpa_p2p_mode & v2->ord) == 0) {
+                               /*
+                                * We requested RTR mode(s), but the peer
+                                * did not pick any mode we support.
+                                */
+                               siw_dbg_cep(cep,
+                                           "rtr mode:  req %2x, got %2x\n",
+                                           mpa_p2p_mode,
+                                           v2->ord & (MPA_V2_RDMA_WRITE_RTR |
+                                                      MPA_V2_RDMA_READ_RTR));
+
+                               siw_init_terminate(qp, TERM_ERROR_LAYER_LLP,
+                                                  LLP_ETYPE_MPA,
+                                                  LLP_ECODE_NO_MATCHING_RTR,
+                                                  0);
+                               siw_send_terminate(qp);
+                               rv = -EPROTO;
+                               goto out_err;
+                       }
+                       mpa_p2p_mode = v2->ord & (MPA_V2_RDMA_WRITE_RTR |
+                                                 MPA_V2_RDMA_READ_RTR);
+               }
+       }
+       memset(&qp_attrs, 0, sizeof(qp_attrs));
+
+       if (rep->params.bits & MPA_RR_FLAG_CRC)
+               qp_attrs.flags = SIW_MPA_CRC;
+
+       qp_attrs.irq_size = cep->ird;
+       qp_attrs.orq_size = cep->ord;
+       qp_attrs.sk = cep->sock;
+       qp_attrs.state = SIW_QP_STATE_RTS;
+
+       qp_attr_mask = SIW_QP_ATTR_STATE | SIW_QP_ATTR_LLP_HANDLE |
+                      SIW_QP_ATTR_ORD | SIW_QP_ATTR_IRD | SIW_QP_ATTR_MPA;
+
+       /* Move socket RX/TX under QP control */
+       down_write(&qp->state_lock);
+       if (qp->attrs.state > SIW_QP_STATE_RTR) {
+               rv = -EINVAL;
+               up_write(&qp->state_lock);
+               goto out_err;
+       }
+       rv = siw_qp_modify(qp, &qp_attrs, qp_attr_mask);
+
+       siw_qp_socket_assoc(cep, qp);
+
+       up_write(&qp->state_lock);
+
+       /* Send extra RDMA frame to trigger peer RTS if negotiated */
+       if (mpa_p2p_mode != MPA_V2_RDMA_NO_RTR) {
+               rv = siw_qp_mpa_rts(qp, mpa_p2p_mode);
+               if (rv)
+                       goto out_err;
+       }
+       if (!rv) {
+               rv = siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, 0);
+               if (!rv)
+                       cep->state = SIW_EPSTATE_RDMA_MODE;
+
+               return 0;
+       }
+
+out_err:
+       siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, -EINVAL);
+
+       return rv;
+}
+
+/*
+ * siw_accept_newconn - accept an incoming pending connection
+ *
+ */
+static void siw_accept_newconn(struct siw_cep *cep)
+{
+       struct socket *s = cep->sock;
+       struct socket *new_s = NULL;
+       struct siw_cep *new_cep = NULL;
+       int rv = 0; /* debug only. should disappear */
+
+       if (cep->state != SIW_EPSTATE_LISTENING)
+               goto error;
+
+       new_cep = siw_cep_alloc(cep->sdev);
+       if (!new_cep)
+               goto error;
+
+       /*
+        * 4: Allocate a sufficient number of work elements
+        * to allow concurrent handling of local + peer close
+        * events, MPA header processing + MPA timeout.
+        */
+       if (siw_cm_alloc_work(new_cep, 4) != 0)
+               goto error;
+
+       /*
+        * Copy saved socket callbacks from listening CEP
+        * and assign new socket with new CEP
+        */
+       new_cep->sk_state_change = cep->sk_state_change;
+       new_cep->sk_data_ready = cep->sk_data_ready;
+       new_cep->sk_write_space = cep->sk_write_space;
+       new_cep->sk_error_report = cep->sk_error_report;
+
+       rv = kernel_accept(s, &new_s, O_NONBLOCK);
+       if (rv != 0) {
+               /*
+                * Connection already aborted by peer..?
+                */
+               siw_dbg_cep(cep, "kernel_accept() error: %d\n", rv);
+               goto error;
+       }
+       new_cep->sock = new_s;
+       siw_cep_get(new_cep);
+       new_s->sk->sk_user_data = new_cep;
+
+       siw_dbg_cep(cep, "listen socket 0x%p, new 0x%p\n", s, new_s);
+
+       if (siw_tcp_nagle == false) {
+               int val = 1;
+
+               rv = kernel_setsockopt(new_s, SOL_TCP, TCP_NODELAY,
+                                      (char *)&val, sizeof(val));
+               if (rv) {
+                       siw_dbg_cep(cep, "setsockopt NODELAY error: %d\n", rv);
+                       goto error;
+               }
+       }
+       new_cep->state = SIW_EPSTATE_AWAIT_MPAREQ;
+
+       rv = siw_cm_queue_work(new_cep, SIW_CM_WORK_MPATIMEOUT);
+       if (rv)
+               goto error;
+       /*
+        * See siw_proc_mpareq() etc. for the use of new_cep->listen_cep.
+        */
+       new_cep->listen_cep = cep;
+       siw_cep_get(cep);
+
+       if (atomic_read(&new_s->sk->sk_rmem_alloc)) {
+               /*
+                * MPA REQ already queued
+                */
+               siw_dbg_cep(cep, "immediate mpa request\n");
+
+               siw_cep_set_inuse(new_cep);
+               rv = siw_proc_mpareq(new_cep);
+               siw_cep_set_free(new_cep);
+
+               if (rv != -EAGAIN) {
+                       siw_cep_put(cep);
+                       new_cep->listen_cep = NULL;
+                       if (rv)
+                               goto error;
+               }
+       }
+       return;
+
+error:
+       if (new_cep)
+               siw_cep_put(new_cep);
+
+       if (new_s) {
+               siw_socket_disassoc(new_s);
+               sock_release(new_s);
+               new_cep->sock = NULL;
+       }
+       siw_dbg_cep(cep, "error %d\n", rv);
+}
+
+static void siw_cm_work_handler(struct work_struct *w)
+{
+       struct siw_cm_work *work;
+       struct siw_cep *cep;
+       int release_cep = 0, rv = 0;
+
+       work = container_of(w, struct siw_cm_work, work.work);
+       cep = work->cep;
+
+       siw_dbg_cep(cep, "[QP %u]: work type: %d, state %d\n",
+                   cep->qp ? qp_id(cep->qp) : -1, work->type, cep->state);
+
+       siw_cep_set_inuse(cep);
+
+       switch (work->type) {
+       case SIW_CM_WORK_ACCEPT:
+               siw_accept_newconn(cep);
+               break;
+
+       case SIW_CM_WORK_READ_MPAHDR:
+               if (cep->state == SIW_EPSTATE_AWAIT_MPAREQ) {
+                       if (cep->listen_cep) {
+                               siw_cep_set_inuse(cep->listen_cep);
+
+                               if (cep->listen_cep->state ==
+                                   SIW_EPSTATE_LISTENING)
+                                       rv = siw_proc_mpareq(cep);
+                               else
+                                       rv = -EFAULT;
+
+                               siw_cep_set_free(cep->listen_cep);
+
+                               if (rv != -EAGAIN) {
+                                       siw_cep_put(cep->listen_cep);
+                                       cep->listen_cep = NULL;
+                                       if (rv)
+                                               siw_cep_put(cep);
+                               }
+                       }
+               } else if (cep->state == SIW_EPSTATE_AWAIT_MPAREP) {
+                       rv = siw_proc_mpareply(cep);
+               } else {
+                       /*
+                        * CEP already moved out of MPA handshake.
+                        * any connection management already done.
+                        * silently ignore the mpa packet.
+                        */
+                       if (cep->state == SIW_EPSTATE_RDMA_MODE) {
+                               cep->sock->sk->sk_data_ready(cep->sock->sk);
+                               siw_dbg_cep(cep, "already in RDMA mode");
+                       } else {
+                               siw_dbg_cep(cep, "out of state: %d\n",
+                                           cep->state);
+                       }
+               }
+               if (rv && rv != EAGAIN)
+                       release_cep = 1;
+               break;
+
+       case SIW_CM_WORK_CLOSE_LLP:
+               /*
+                * QP scheduled LLP close
+                */
+               if (cep->qp && cep->qp->term_info.valid)
+                       siw_send_terminate(cep->qp);
+
+               if (cep->cm_id)
+                       siw_cm_upcall(cep, IW_CM_EVENT_CLOSE, 0);
+
+               release_cep = 1;
+               break;
+
+       case SIW_CM_WORK_PEER_CLOSE:
+               if (cep->cm_id) {
+                       if (cep->state == SIW_EPSTATE_AWAIT_MPAREP) {
+                               /*
+                                * MPA reply not received, but connection drop
+                                */
+                               siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+                                             -ECONNRESET);
+                       } else if (cep->state == SIW_EPSTATE_RDMA_MODE) {
+                               /*
+                                * NOTE: IW_CM_EVENT_DISCONNECT is given just
+                                *       to transition IWCM into CLOSING.
+                                */
+                               siw_cm_upcall(cep, IW_CM_EVENT_DISCONNECT, 0);
+                               siw_cm_upcall(cep, IW_CM_EVENT_CLOSE, 0);
+                       }
+                       /*
+                        * for other states there is no connection
+                        * known to the IWCM.
+                        */
+               } else {
+                       if (cep->state == SIW_EPSTATE_RECVD_MPAREQ) {
+                               /*
+                                * Wait for the ulp/CM to call accept/reject
+                                */
+                               siw_dbg_cep(cep,
+                                           "mpa req recvd, wait for ULP\n");
+                       } else if (cep->state == SIW_EPSTATE_AWAIT_MPAREQ) {
+                               /*
+                                * Socket close before MPA request received.
+                                */
+                               siw_dbg_cep(cep, "no mpareq: drop listener\n");
+                               siw_cep_put(cep->listen_cep);
+                               cep->listen_cep = NULL;
+                       }
+               }
+               release_cep = 1;
+               break;
+
+       case SIW_CM_WORK_MPATIMEOUT:
+               cep->mpa_timer = NULL;
+
+               if (cep->state == SIW_EPSTATE_AWAIT_MPAREP) {
+                       /*
+                        * MPA request timed out:
+                        * Hide any partially received private data and signal
+                        * timeout
+                        */
+                       cep->mpa.hdr.params.pd_len = 0;
+
+                       if (cep->cm_id)
+                               siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+                                             -ETIMEDOUT);
+                       release_cep = 1;
+
+               } else if (cep->state == SIW_EPSTATE_AWAIT_MPAREQ) {
+                       /*
+                        * No MPA request received after peer TCP stream setup.
+                        */
+                       if (cep->listen_cep) {
+                               siw_cep_put(cep->listen_cep);
+                               cep->listen_cep = NULL;
+                       }
+                       release_cep = 1;
+               }
+               break;
+
+       default:
+               WARN(1, "Undefined CM work type: %d\n", work->type);
+       }
+       if (release_cep) {
+               siw_dbg_cep(cep,
+                           "release: timer=%s, QP[%u], id 0x%p\n",
+                           cep->mpa_timer ? "y" : "n",
+                           cep->qp ? qp_id(cep->qp) : -1, cep->cm_id);
+
+               siw_cancel_mpatimer(cep);
+
+               cep->state = SIW_EPSTATE_CLOSED;
+
+               if (cep->qp) {
+                       struct siw_qp *qp = cep->qp;
+                       /*
+                        * Serialize a potential race with application
+                        * closing the QP and calling siw_qp_cm_drop()
+                        */
+                       siw_qp_get(qp);
+                       siw_cep_set_free(cep);
+
+                       siw_qp_llp_close(qp);
+                       siw_qp_put(qp);
+
+                       siw_cep_set_inuse(cep);
+                       cep->qp = NULL;
+                       siw_qp_put(qp);
+               }
+               if (cep->sock) {
+                       siw_socket_disassoc(cep->sock);
+                       sock_release(cep->sock);
+                       cep->sock = NULL;
+               }
+               if (cep->cm_id) {
+                       cep->cm_id->rem_ref(cep->cm_id);
+                       cep->cm_id = NULL;
+                       siw_cep_put(cep);
+               }
+       }
+       siw_cep_set_free(cep);
+       siw_put_work(work);
+       siw_cep_put(cep);
+}
+
+static struct workqueue_struct *siw_cm_wq;
+
+int siw_cm_queue_work(struct siw_cep *cep, enum siw_work_type type)
+{
+       struct siw_cm_work *work = siw_get_work(cep);
+       unsigned long delay = 0;
+
+       if (!work) {
+               siw_dbg_cep(cep, "failed with no work available\n");
+               return -ENOMEM;
+       }
+       work->type = type;
+       work->cep = cep;
+
+       siw_cep_get(cep);
+
+       INIT_DELAYED_WORK(&work->work, siw_cm_work_handler);
+
+       if (type == SIW_CM_WORK_MPATIMEOUT) {
+               cep->mpa_timer = work;
+
+               if (cep->state == SIW_EPSTATE_AWAIT_MPAREP)
+                       delay = MPAREQ_TIMEOUT;
+               else
+                       delay = MPAREP_TIMEOUT;
+       }
+       siw_dbg_cep(cep, "[QP %u]: work type: %d, work 0x%p, timeout %lu\n",
+                   cep->qp ? qp_id(cep->qp) : -1, type, work, delay);
+
+       queue_delayed_work(siw_cm_wq, &work->work, delay);
+
+       return 0;
+}
+
+static void siw_cm_llp_data_ready(struct sock *sk)
+{
+       struct siw_cep *cep;
+
+       read_lock(&sk->sk_callback_lock);
+
+       cep = sk_to_cep(sk);
+       if (!cep) {
+               WARN_ON(1);
+               goto out;
+       }
+       siw_dbg_cep(cep, "state: %d\n", cep->state);
+
+       switch (cep->state) {
+       case SIW_EPSTATE_RDMA_MODE:
+               /* fall through */
+       case SIW_EPSTATE_LISTENING:
+               break;
+
+       case SIW_EPSTATE_AWAIT_MPAREQ:
+               /* fall through */
+       case SIW_EPSTATE_AWAIT_MPAREP:
+               siw_cm_queue_work(cep, SIW_CM_WORK_READ_MPAHDR);
+               break;
+
+       default:
+               siw_dbg_cep(cep, "unexpected data, state %d\n", cep->state);
+               break;
+       }
+out:
+       read_unlock(&sk->sk_callback_lock);
+}
+
+static void siw_cm_llp_write_space(struct sock *sk)
+{
+       struct siw_cep *cep = sk_to_cep(sk);
+
+       if (cep)
+               siw_dbg_cep(cep, "state: %d\n", cep->state);
+}
+
+static void siw_cm_llp_error_report(struct sock *sk)
+{
+       struct siw_cep *cep = sk_to_cep(sk);
+
+       if (cep) {
+               siw_dbg_cep(cep, "error %d, socket state: %d, cep state: %d\n",
+                           sk->sk_err, sk->sk_state, cep->state);
+               cep->sk_error_report(sk);
+       }
+}
+
+static void siw_cm_llp_state_change(struct sock *sk)
+{
+       struct siw_cep *cep;
+       struct socket *s;
+       void (*orig_state_change)(struct sock *s);
+
+       read_lock(&sk->sk_callback_lock);
+
+       cep = sk_to_cep(sk);
+       if (!cep) {
+               /* endpoint already disassociated */
+               read_unlock(&sk->sk_callback_lock);
+               return;
+       }
+       orig_state_change = cep->sk_state_change;
+
+       s = sk->sk_socket;
+
+       siw_dbg_cep(cep, "state: %d\n", cep->state);
+
+       switch (sk->sk_state) {
+       case TCP_ESTABLISHED:
+               /*
+                * handle accepting socket as special case where only
+                * new connection is possible
+                */
+               siw_cm_queue_work(cep, SIW_CM_WORK_ACCEPT);
+               break;
+
+       case TCP_CLOSE:
+       case TCP_CLOSE_WAIT:
+               if (cep->qp)
+                       cep->qp->tx_ctx.tx_suspend = 1;
+               siw_cm_queue_work(cep, SIW_CM_WORK_PEER_CLOSE);
+               break;
+
+       default:
+               siw_dbg_cep(cep, "unexpected socket state %d\n", sk->sk_state);
+       }
+       read_unlock(&sk->sk_callback_lock);
+       orig_state_change(sk);
+}
+
+static int kernel_bindconnect(struct socket *s, struct sockaddr *laddr,
+                             struct sockaddr *raddr)
+{
+       int rv, flags = 0, s_val = 1;
+       size_t size = laddr->sa_family == AF_INET ?
+               sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6);
+
+       /*
+        * Make address available again asap.
+        */
+       rv = kernel_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&s_val,
+                              sizeof(s_val));
+       if (rv < 0)
+               return rv;
+
+       rv = s->ops->bind(s, laddr, size);
+       if (rv < 0)
+               return rv;
+
+       rv = s->ops->connect(s, raddr, size, flags);
+
+       return rv < 0 ? rv : 0;
+}
+
+int siw_connect(struct iw_cm_id *id, struct iw_cm_conn_param *params)
+{
+       struct siw_device *sdev = to_siw_dev(id->device);
+       struct siw_qp *qp;
+       struct siw_cep *cep = NULL;
+       struct socket *s = NULL;
+       struct sockaddr *laddr = (struct sockaddr *)&id->local_addr,
+                       *raddr = (struct sockaddr *)&id->remote_addr;
+       bool p2p_mode = peer_to_peer, v4 = true;
+       u16 pd_len = params->private_data_len;
+       int version = mpa_version, rv;
+
+       if (pd_len > MPA_MAX_PRIVDATA)
+               return -EINVAL;
+
+       if (params->ird > sdev->attrs.max_ird ||
+           params->ord > sdev->attrs.max_ord)
+               return -ENOMEM;
+
+       if (laddr->sa_family == AF_INET6)
+               v4 = false;
+       else if (laddr->sa_family != AF_INET)
+               return -EAFNOSUPPORT;
+
+       /*
+        * Respect any iwarp port mapping: Use mapped remote address
+        * if valid. Local address must not be mapped, since siw
+        * uses kernel TCP stack.
+        */
+       if ((v4 && to_sockaddr_in(id->remote_addr).sin_port != 0) ||
+            to_sockaddr_in6(id->remote_addr).sin6_port != 0)
+               raddr = (struct sockaddr *)&id->m_remote_addr;
+
+       qp = siw_qp_id2obj(sdev, params->qpn);
+       if (!qp) {
+               WARN(1, "[QP %u] does not exist\n", params->qpn);
+               rv = -EINVAL;
+               goto error;
+       }
+       if (v4)
+               siw_dbg_qp(qp,
+                          "id 0x%p, pd_len %d, laddr %pI4 %d, raddr %pI4 %d\n",
+                          id, pd_len,
+                          &((struct sockaddr_in *)(laddr))->sin_addr,
+                          ntohs(((struct sockaddr_in *)(laddr))->sin_port),
+                          &((struct sockaddr_in *)(raddr))->sin_addr,
+                          ntohs(((struct sockaddr_in *)(raddr))->sin_port));
+       else
+               siw_dbg_qp(qp,
+                          "id 0x%p, pd_len %d, laddr %pI6 %d, raddr %pI6 %d\n",
+                          id, pd_len,
+                          &((struct sockaddr_in6 *)(laddr))->sin6_addr,
+                          ntohs(((struct sockaddr_in6 *)(laddr))->sin6_port),
+                          &((struct sockaddr_in6 *)(raddr))->sin6_addr,
+                          ntohs(((struct sockaddr_in6 *)(raddr))->sin6_port));
+
+       rv = sock_create(v4 ? AF_INET : AF_INET6, SOCK_STREAM, IPPROTO_TCP, &s);
+       if (rv < 0)
+               goto error;
+
+       /*
+        * NOTE: For simplification, connect() is called in blocking
+        * mode. Might be reconsidered for async connection setup at
+        * TCP level.
+        */
+       rv = kernel_bindconnect(s, laddr, raddr);
+       if (rv != 0) {
+               siw_dbg_qp(qp, "kernel_bindconnect: error %d\n", rv);
+               goto error;
+       }
+       if (siw_tcp_nagle == false) {
+               int val = 1;
+
+               rv = kernel_setsockopt(s, SOL_TCP, TCP_NODELAY, (char *)&val,
+                                      sizeof(val));
+               if (rv) {
+                       siw_dbg_qp(qp, "setsockopt NODELAY error: %d\n", rv);
+                       goto error;
+               }
+       }
+       cep = siw_cep_alloc(sdev);
+       if (!cep) {
+               rv = -ENOMEM;
+               goto error;
+       }
+       siw_cep_set_inuse(cep);
+
+       /* Associate QP with CEP */
+       siw_cep_get(cep);
+       qp->cep = cep;
+
+       /* siw_qp_get(qp) already done by QP lookup */
+       cep->qp = qp;
+
+       id->add_ref(id);
+       cep->cm_id = id;
+
+       /*
+        * 4: Allocate a sufficient number of work elements
+        * to allow concurrent handling of local + peer close
+        * events, MPA header processing + MPA timeout.
+        */
+       rv = siw_cm_alloc_work(cep, 4);
+       if (rv != 0) {
+               rv = -ENOMEM;
+               goto error;
+       }
+       cep->ird = params->ird;
+       cep->ord = params->ord;
+
+       if (p2p_mode && cep->ord == 0)
+               cep->ord = 1;
+
+       cep->state = SIW_EPSTATE_CONNECTING;
+
+       /*
+        * Associate CEP with socket
+        */
+       siw_cep_socket_assoc(cep, s);
+
+       cep->state = SIW_EPSTATE_AWAIT_MPAREP;
+
+       /*
+        * Set MPA Request bits: CRC if required, no MPA Markers,
+        * MPA Rev. according to module parameter 'mpa_version', Key 'Request'.
+        */
+       cep->mpa.hdr.params.bits = 0;
+       if (version > MPA_REVISION_2) {
+               pr_warn("Setting MPA version to %u\n", MPA_REVISION_2);
+               version = MPA_REVISION_2;
+               /* Adjust also module parameter */
+               mpa_version = MPA_REVISION_2;
+       }
+       __mpa_rr_set_revision(&cep->mpa.hdr.params.bits, version);
+
+       if (try_gso)
+               cep->mpa.hdr.params.bits |= MPA_RR_FLAG_GSO_EXP;
+
+       if (mpa_crc_required)
+               cep->mpa.hdr.params.bits |= MPA_RR_FLAG_CRC;
+
+       /*
+        * If MPA version == 2:
+        * o Include ORD and IRD.
+        * o Indicate peer-to-peer mode, if required by module
+        *   parameter 'peer_to_peer'.
+        */
+       if (version == MPA_REVISION_2) {
+               cep->enhanced_rdma_conn_est = true;
+               cep->mpa.hdr.params.bits |= MPA_RR_FLAG_ENHANCED;
+
+               cep->mpa.v2_ctrl.ird = htons(cep->ird);
+               cep->mpa.v2_ctrl.ord = htons(cep->ord);
+
+               if (p2p_mode) {
+                       cep->mpa.v2_ctrl.ird |= MPA_V2_PEER_TO_PEER;
+                       cep->mpa.v2_ctrl.ord |= rtr_type;
+               }
+               /* Remember own P2P mode requested */
+               cep->mpa.v2_ctrl_req.ird = cep->mpa.v2_ctrl.ird;
+               cep->mpa.v2_ctrl_req.ord = cep->mpa.v2_ctrl.ord;
+       }
+       memcpy(cep->mpa.hdr.key, MPA_KEY_REQ, 16);
+
+       rv = siw_send_mpareqrep(cep, params->private_data, pd_len);
+       /*
+        * Reset private data.
+        */
+       cep->mpa.hdr.params.pd_len = 0;
+
+       if (rv >= 0) {
+               rv = siw_cm_queue_work(cep, SIW_CM_WORK_MPATIMEOUT);
+               if (!rv) {
+                       siw_dbg_cep(cep, "id 0x%p, [QP %u]: exit\n", id,
+                                   qp_id(qp));
+                       siw_cep_set_free(cep);
+                       return 0;
+               }
+       }
+error:
+       siw_dbg_qp(qp, "failed: %d\n", rv);
+
+       if (cep) {
+               siw_socket_disassoc(s);
+               sock_release(s);
+               cep->sock = NULL;
+
+               cep->qp = NULL;
+
+               cep->cm_id = NULL;
+               id->rem_ref(id);
+               siw_cep_put(cep);
+
+               qp->cep = NULL;
+               siw_cep_put(cep);
+
+               cep->state = SIW_EPSTATE_CLOSED;
+
+               siw_cep_set_free(cep);
+
+               siw_cep_put(cep);
+
+       } else if (s) {
+               sock_release(s);
+       }
+       siw_qp_put(qp);
+
+       return rv;
+}
+
+/*
+ * siw_accept - Let SoftiWARP accept an RDMA connection request
+ *
+ * @id:                New connection management id to be used for accepted
+ *             connection request
+ * @params:    Connection parameters provided by ULP for accepting connection
+ *
+ * Transition QP to RTS state, associate new CM id @id with accepted CEP
+ * and get prepared for TCP input by installing socket callbacks.
+ * Then send MPA Reply and generate the "connection established" event.
+ * Socket callbacks must be installed before sending MPA Reply, because
+ * the latter may cause a first RDMA message to arrive from the RDMA Initiator
+ * side very quickly, at which time the socket callbacks must be ready.
+ */
+int siw_accept(struct iw_cm_id *id, struct iw_cm_conn_param *params)
+{
+       struct siw_device *sdev = to_siw_dev(id->device);
+       struct siw_cep *cep = (struct siw_cep *)id->provider_data;
+       struct siw_qp *qp;
+       struct siw_qp_attrs qp_attrs;
+       int rv, max_priv_data = MPA_MAX_PRIVDATA;
+       bool wait_for_peer_rts = false;
+
+       siw_cep_set_inuse(cep);
+       siw_cep_put(cep);
+
+       /* Free lingering inbound private data */
+       if (cep->mpa.hdr.params.pd_len) {
+               cep->mpa.hdr.params.pd_len = 0;
+               kfree(cep->mpa.pdata);
+               cep->mpa.pdata = NULL;
+       }
+       siw_cancel_mpatimer(cep);
+
+       if (cep->state != SIW_EPSTATE_RECVD_MPAREQ) {
+               siw_dbg_cep(cep, "id 0x%p: out of state\n", id);
+
+               siw_cep_set_free(cep);
+               siw_cep_put(cep);
+
+               return -ECONNRESET;
+       }
+       qp = siw_qp_id2obj(sdev, params->qpn);
+       if (!qp) {
+               WARN(1, "[QP %d] does not exist\n", params->qpn);
+               siw_cep_set_free(cep);
+               siw_cep_put(cep);
+
+               return -EINVAL;
+       }
+       down_write(&qp->state_lock);
+       if (qp->attrs.state > SIW_QP_STATE_RTR) {
+               rv = -EINVAL;
+               up_write(&qp->state_lock);
+               goto error;
+       }
+       siw_dbg_cep(cep, "id 0x%p\n", id);
+
+       if (try_gso && cep->mpa.hdr.params.bits & MPA_RR_FLAG_GSO_EXP) {
+               siw_dbg_cep(cep, "peer allows GSO on TX\n");
+               qp->tx_ctx.gso_seg_limit = 0;
+       }
+       if (params->ord > sdev->attrs.max_ord ||
+           params->ird > sdev->attrs.max_ird) {
+               siw_dbg_cep(
+                       cep,
+                       "id 0x%p, [QP %u]: ord %d (max %d), ird %d (max %d)\n",
+                       id, qp_id(qp), params->ord, sdev->attrs.max_ord,
+                       params->ird, sdev->attrs.max_ird);
+               rv = -EINVAL;
+               up_write(&qp->state_lock);
+               goto error;
+       }
+       if (cep->enhanced_rdma_conn_est)
+               max_priv_data -= sizeof(struct mpa_v2_data);
+
+       if (params->private_data_len > max_priv_data) {
+               siw_dbg_cep(
+                       cep,
+                       "id 0x%p, [QP %u]: private data length: %d (max %d)\n",
+                       id, qp_id(qp), params->private_data_len, max_priv_data);
+               rv = -EINVAL;
+               up_write(&qp->state_lock);
+               goto error;
+       }
+       if (cep->enhanced_rdma_conn_est) {
+               if (params->ord > cep->ord) {
+                       if (relaxed_ird_negotiation) {
+                               params->ord = cep->ord;
+                       } else {
+                               cep->ird = params->ird;
+                               cep->ord = params->ord;
+                               rv = -EINVAL;
+                               up_write(&qp->state_lock);
+                               goto error;
+                       }
+               }
+               if (params->ird < cep->ird) {
+                       if (relaxed_ird_negotiation &&
+                           cep->ird <= sdev->attrs.max_ird)
+                               params->ird = cep->ird;
+                       else {
+                               rv = -ENOMEM;
+                               up_write(&qp->state_lock);
+                               goto error;
+                       }
+               }
+               if (cep->mpa.v2_ctrl.ord &
+                   (MPA_V2_RDMA_WRITE_RTR | MPA_V2_RDMA_READ_RTR))
+                       wait_for_peer_rts = true;
+               /*
+                * Signal back negotiated IRD and ORD values
+                */
+               cep->mpa.v2_ctrl.ord =
+                       htons(params->ord & MPA_IRD_ORD_MASK) |
+                       (cep->mpa.v2_ctrl.ord & ~MPA_V2_MASK_IRD_ORD);
+               cep->mpa.v2_ctrl.ird =
+                       htons(params->ird & MPA_IRD_ORD_MASK) |
+                       (cep->mpa.v2_ctrl.ird & ~MPA_V2_MASK_IRD_ORD);
+       }
+       cep->ird = params->ird;
+       cep->ord = params->ord;
+
+       cep->cm_id = id;
+       id->add_ref(id);
+
+       memset(&qp_attrs, 0, sizeof(qp_attrs));
+       qp_attrs.orq_size = cep->ord;
+       qp_attrs.irq_size = cep->ird;
+       qp_attrs.sk = cep->sock;
+       if (cep->mpa.hdr.params.bits & MPA_RR_FLAG_CRC)
+               qp_attrs.flags = SIW_MPA_CRC;
+       qp_attrs.state = SIW_QP_STATE_RTS;
+
+       siw_dbg_cep(cep, "id 0x%p, [QP%u]: moving to rts\n", id, qp_id(qp));
+
+       /* Associate QP with CEP */
+       siw_cep_get(cep);
+       qp->cep = cep;
+
+       /* siw_qp_get(qp) already done by QP lookup */
+       cep->qp = qp;
+
+       cep->state = SIW_EPSTATE_RDMA_MODE;
+
+       /* Move socket RX/TX under QP control */
+       rv = siw_qp_modify(qp, &qp_attrs,
+                          SIW_QP_ATTR_STATE | SIW_QP_ATTR_LLP_HANDLE |
+                                  SIW_QP_ATTR_ORD | SIW_QP_ATTR_IRD |
+                                  SIW_QP_ATTR_MPA);
+       up_write(&qp->state_lock);
+
+       if (rv)
+               goto error;
+
+       siw_dbg_cep(cep, "id 0x%p, [QP %u]: send mpa reply, %d byte pdata\n",
+                   id, qp_id(qp), params->private_data_len);
+
+       rv = siw_send_mpareqrep(cep, params->private_data,
+                               params->private_data_len);
+       if (rv != 0)
+               goto error;
+
+       if (wait_for_peer_rts) {
+               siw_sk_assign_rtr_upcalls(cep);
+       } else {
+               siw_qp_socket_assoc(cep, qp);
+               rv = siw_cm_upcall(cep, IW_CM_EVENT_ESTABLISHED, 0);
+               if (rv)
+                       goto error;
+       }
+       siw_cep_set_free(cep);
+
+       return 0;
+error:
+       siw_socket_disassoc(cep->sock);
+       sock_release(cep->sock);
+       cep->sock = NULL;
+
+       cep->state = SIW_EPSTATE_CLOSED;
+
+       if (cep->cm_id) {
+               cep->cm_id->rem_ref(id);
+               cep->cm_id = NULL;
+       }
+       if (qp->cep) {
+               siw_cep_put(cep);
+               qp->cep = NULL;
+       }
+       cep->qp = NULL;
+       siw_qp_put(qp);
+
+       siw_cep_set_free(cep);
+       siw_cep_put(cep);
+
+       return rv;
+}
+
+/*
+ * siw_reject()
+ *
+ * Local connection reject case. Send private data back to peer,
+ * close connection and dereference connection id.
+ */
+int siw_reject(struct iw_cm_id *id, const void *pdata, u8 pd_len)
+{
+       struct siw_cep *cep = (struct siw_cep *)id->provider_data;
+
+       siw_cep_set_inuse(cep);
+       siw_cep_put(cep);
+
+       siw_cancel_mpatimer(cep);
+
+       if (cep->state != SIW_EPSTATE_RECVD_MPAREQ) {
+               siw_dbg_cep(cep, "id 0x%p: out of state\n", id);
+
+               siw_cep_set_free(cep);
+               siw_cep_put(cep); /* put last reference */
+
+               return -ECONNRESET;
+       }
+       siw_dbg_cep(cep, "id 0x%p, cep->state %d, pd_len %d\n", id, cep->state,
+                   pd_len);
+
+       if (__mpa_rr_revision(cep->mpa.hdr.params.bits) >= MPA_REVISION_1) {
+               cep->mpa.hdr.params.bits |= MPA_RR_FLAG_REJECT; /* reject */
+               siw_send_mpareqrep(cep, pdata, pd_len);
+       }
+       siw_socket_disassoc(cep->sock);
+       sock_release(cep->sock);
+       cep->sock = NULL;
+
+       cep->state = SIW_EPSTATE_CLOSED;
+
+       siw_cep_set_free(cep);
+       siw_cep_put(cep);
+
+       return 0;
+}
+
+static int siw_listen_address(struct iw_cm_id *id, int backlog,
+                             struct sockaddr *laddr, int addr_family)
+{
+       struct socket *s;
+       struct siw_cep *cep = NULL;
+       struct siw_device *sdev = to_siw_dev(id->device);
+       int rv = 0, s_val;
+
+       rv = sock_create(addr_family, SOCK_STREAM, IPPROTO_TCP, &s);
+       if (rv < 0)
+               return rv;
+
+       /*
+        * Allow binding local port when still in TIME_WAIT from last close.
+        */
+       s_val = 1;
+       rv = kernel_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&s_val,
+                              sizeof(s_val));
+       if (rv) {
+               siw_dbg(id->device, "id 0x%p: setsockopt error: %d\n", id, rv);
+               goto error;
+       }
+       rv = s->ops->bind(s, laddr, addr_family == AF_INET ?
+                                   sizeof(struct sockaddr_in) :
+                                   sizeof(struct sockaddr_in6));
+       if (rv) {
+               siw_dbg(id->device, "id 0x%p: socket bind error: %d\n", id, rv);
+               goto error;
+       }
+       cep = siw_cep_alloc(sdev);
+       if (!cep) {
+               rv = -ENOMEM;
+               goto error;
+       }
+       siw_cep_socket_assoc(cep, s);
+
+       rv = siw_cm_alloc_work(cep, backlog);
+       if (rv) {
+               siw_dbg(id->device,
+                       "id 0x%p: alloc_work error %d, backlog %d\n", id,
+                       rv, backlog);
+               goto error;
+       }
+       rv = s->ops->listen(s, backlog);
+       if (rv) {
+               siw_dbg(id->device, "id 0x%p: listen error %d\n", id, rv);
+               goto error;
+       }
+       cep->cm_id = id;
+       id->add_ref(id);
+
+       /*
+        * In case of a wildcard rdma_listen on a multi-homed device,
+        * a listener's IWCM id is associated with more than one listening CEP.
+        *
+        * We currently use id->provider_data in three different ways:
+        *
+        * o For a listener's IWCM id, id->provider_data points to
+        *   the list_head of the list of listening CEPs.
+        *   Uses: siw_create_listen(), siw_destroy_listen()
+        *
+        * o For each accepted passive-side IWCM id, id->provider_data
+        *   points to the CEP itself. This is a consequence of
+        *   - siw_cm_upcall() setting event.provider_data = cep and
+        *   - the IWCM's cm_conn_req_handler() setting provider_data of the
+        *     new passive-side IWCM id equal to event.provider_data
+        *   Uses: siw_accept(), siw_reject()
+        *
+        * o For an active-side IWCM id, id->provider_data is not used at all.
+        *
+        */
+       if (!id->provider_data) {
+               id->provider_data =
+                       kmalloc(sizeof(struct list_head), GFP_KERNEL);
+               if (!id->provider_data) {
+                       rv = -ENOMEM;
+                       goto error;
+               }
+               INIT_LIST_HEAD((struct list_head *)id->provider_data);
+       }
+       list_add_tail(&cep->listenq, (struct list_head *)id->provider_data);
+       cep->state = SIW_EPSTATE_LISTENING;
+
+       if (addr_family == AF_INET)
+               siw_dbg(id->device, "Listen at laddr %pI4 %u\n",
+                       &(((struct sockaddr_in *)laddr)->sin_addr),
+                       ((struct sockaddr_in *)laddr)->sin_port);
+       else
+               siw_dbg(id->device, "Listen at laddr %pI6 %u\n",
+                       &(((struct sockaddr_in6 *)laddr)->sin6_addr),
+                       ((struct sockaddr_in6 *)laddr)->sin6_port);
+
+       return 0;
+
+error:
+       siw_dbg(id->device, "failed: %d\n", rv);
+
+       if (cep) {
+               siw_cep_set_inuse(cep);
+
+               if (cep->cm_id) {
+                       cep->cm_id->rem_ref(cep->cm_id);
+                       cep->cm_id = NULL;
+               }
+               cep->sock = NULL;
+               siw_socket_disassoc(s);
+               cep->state = SIW_EPSTATE_CLOSED;
+
+               siw_cep_set_free(cep);
+               siw_cep_put(cep);
+       }
+       sock_release(s);
+
+       return rv;
+}
+
+static void siw_drop_listeners(struct iw_cm_id *id)
+{
+       struct list_head *p, *tmp;
+
+       /*
+        * In case of a wildcard rdma_listen on a multi-homed device,
+        * a listener's IWCM id is associated with more than one listening CEP.
+        */
+       list_for_each_safe(p, tmp, (struct list_head *)id->provider_data) {
+               struct siw_cep *cep = list_entry(p, struct siw_cep, listenq);
+
+               list_del(p);
+
+               siw_dbg_cep(cep, "id 0x%p: drop cep, state %d\n", id,
+                           cep->state);
+
+               siw_cep_set_inuse(cep);
+
+               if (cep->cm_id) {
+                       cep->cm_id->rem_ref(cep->cm_id);
+                       cep->cm_id = NULL;
+               }
+               if (cep->sock) {
+                       siw_socket_disassoc(cep->sock);
+                       sock_release(cep->sock);
+                       cep->sock = NULL;
+               }
+               cep->state = SIW_EPSTATE_CLOSED;
+               siw_cep_set_free(cep);
+               siw_cep_put(cep);
+       }
+}
+
+/*
+ * siw_create_listen - Create resources for a listener's IWCM ID @id
+ *
+ * Listens on the socket addresses id->local_addr and id->remote_addr.
+ *
+ * If the listener's @id provides a specific local IP address, at most one
+ * listening socket is created and associated with @id.
+ *
+ * If the listener's @id provides the wildcard (zero) local IP address,
+ * a separate listen is performed for each local IP address of the device
+ * by creating a listening socket and binding to that local IP address.
+ *
+ */
+int siw_create_listen(struct iw_cm_id *id, int backlog)
+{
+       struct net_device *dev = to_siw_dev(id->device)->netdev;
+       int rv = 0, listeners = 0;
+
+       siw_dbg(id->device, "id 0x%p: backlog %d\n", id, backlog);
+
+       /*
+        * For each attached address of the interface, create a
+        * listening socket, if id->local_addr is the wildcard
+        * IP address or matches the IP address.
+        */
+       if (id->local_addr.ss_family == AF_INET) {
+               struct in_device *in_dev = in_dev_get(dev);
+               struct sockaddr_in s_laddr, *s_raddr;
+
+               memcpy(&s_laddr, &id->local_addr, sizeof(s_laddr));
+               s_raddr = (struct sockaddr_in *)&id->remote_addr;
+
+               siw_dbg(id->device,
+                       "id 0x%p: laddr %pI4:%d, raddr %pI4:%d\n",
+                       id, &s_laddr.sin_addr, ntohs(s_laddr.sin_port),
+                       &s_raddr->sin_addr, ntohs(s_raddr->sin_port));
+
+               for_ifa(in_dev)
+               {
+                       if (ipv4_is_zeronet(s_laddr.sin_addr.s_addr) ||
+                           s_laddr.sin_addr.s_addr == ifa->ifa_address) {
+                               s_laddr.sin_addr.s_addr = ifa->ifa_address;
+
+                               rv = siw_listen_address(id, backlog,
+                                               (struct sockaddr *)&s_laddr,
+                                               AF_INET);
+                               if (!rv)
+                                       listeners++;
+                       }
+               }
+               endfor_ifa(in_dev);
+               in_dev_put(in_dev);
+       } else if (id->local_addr.ss_family == AF_INET6) {
+               struct inet6_dev *in6_dev = in6_dev_get(dev);
+               struct inet6_ifaddr *ifp;
+               struct sockaddr_in6 *s_laddr = &to_sockaddr_in6(id->local_addr),
+                       *s_raddr = &to_sockaddr_in6(id->remote_addr);
+
+               siw_dbg(id->device,
+                       "id 0x%p: laddr %pI6:%d, raddr %pI6:%d\n",
+                       id, &s_laddr->sin6_addr, ntohs(s_laddr->sin6_port),
+                       &s_raddr->sin6_addr, ntohs(s_raddr->sin6_port));
+
+               read_lock_bh(&in6_dev->lock);
+               list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
+                       struct sockaddr_in6 bind_addr;
+
+                       if (ipv6_addr_any(&s_laddr->sin6_addr) ||
+                           ipv6_addr_equal(&s_laddr->sin6_addr, &ifp->addr)) {
+                               bind_addr.sin6_family = AF_INET6;
+                               bind_addr.sin6_port = s_laddr->sin6_port;
+                               bind_addr.sin6_flowinfo = 0;
+                               bind_addr.sin6_addr = ifp->addr;
+                               bind_addr.sin6_scope_id = dev->ifindex;
+
+                               rv = siw_listen_address(id, backlog,
+                                               (struct sockaddr *)&bind_addr,
+                                               AF_INET6);
+                               if (!rv)
+                                       listeners++;
+                       }
+               }
+               read_unlock_bh(&in6_dev->lock);
+
+               in6_dev_put(in6_dev);
+       } else {
+               return -EAFNOSUPPORT;
+       }
+       if (listeners)
+               rv = 0;
+       else if (!rv)
+               rv = -EINVAL;
+
+       siw_dbg(id->device, "id 0x%p: %s\n", id, rv ? "FAIL" : "OK");
+
+       return rv;
+}
+
+int siw_destroy_listen(struct iw_cm_id *id)
+{
+       siw_dbg(id->device, "id 0x%p\n", id);
+
+       if (!id->provider_data) {
+               siw_dbg(id->device, "id 0x%p: no cep(s)\n", id);
+               return 0;
+       }
+       siw_drop_listeners(id);
+       kfree(id->provider_data);
+       id->provider_data = NULL;
+
+       return 0;
+}
+
+int siw_cm_init(void)
+{
+       /*
+        * create_single_workqueue for strict ordering
+        */
+       siw_cm_wq = create_singlethread_workqueue("siw_cm_wq");
+       if (!siw_cm_wq)
+               return -ENOMEM;
+
+       return 0;
+}
+
+void siw_cm_exit(void)
+{
+       if (siw_cm_wq) {
+               flush_workqueue(siw_cm_wq);
+               destroy_workqueue(siw_cm_wq);
+       }
+}
diff --git a/drivers/infiniband/sw/siw/siw_cm.h b/drivers/infiniband/sw/siw/siw_cm.h
new file mode 100644 (file)
index 0000000..8c59cb3
--- /dev/null
@@ -0,0 +1,133 @@
+/* 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