/*******************************************************************************
*
* Copyright (c) 2015-2016 Intel Corporation.  All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses.  You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenFabrics.org BSD license below:
*
*   Redistribution and use in source and binary forms, with or
*   without modification, are permitted provided that the following
*   conditions are met:
*
*    - Redistributions of source code must retain the above
*       copyright notice, this list of conditions and the following
*       disclaimer.
*
*    - Redistributions in binary form must reproduce the above
*       copyright notice, this list of conditions and the following
*       disclaimer in the documentation and/or other materials
*       provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*******************************************************************************/

#include <linux/atomic.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/init.h>
#include <linux/if_arp.h>
#include <linux/if_vlan.h>
#include <linux/notifier.h>
#include <linux/net.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/time.h>
#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/netdevice.h>
#include <linux/random.h>
#include <linux/list.h>
#include <linux/threads.h>
#include <linux/highmem.h>
#include <net/arp.h>
#include <net/ndisc.h>
#include <net/neighbour.h>
#include <net/route.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include <net/ip_fib.h>
#include <net/secure_seq.h>
#include <net/tcp.h>
#include <asm/checksum.h>

#include "i40iw.h"

static void i40iw_rem_ref_cm_node(struct i40iw_cm_node *);
static void i40iw_cm_post_event(struct i40iw_cm_event *event);
static void i40iw_disconnect_worker(struct work_struct *work);

/**
 * i40iw_free_sqbuf - put back puda buffer if refcount = 0
 * @vsi: pointer to vsi structure
 * @buf: puda buffer to free
 */
void i40iw_free_sqbuf(struct i40iw_sc_vsi *vsi, void *bufp)
{
        struct i40iw_puda_buf *buf = (struct i40iw_puda_buf *)bufp;
        struct i40iw_puda_rsrc *ilq = vsi->ilq;

        if (!atomic_dec_return(&buf->refcount))
                i40iw_puda_ret_bufpool(ilq, buf);
}

/**
 * i40iw_derive_hw_ird_setting - Calculate IRD
 *
 * @cm_ird: IRD of connection's node
 *
 * The ird from the connection is rounded to a supported HW
 * setting (2,8,32,64) and then encoded for ird_size field of
 * qp_ctx
 */
static u8 i40iw_derive_hw_ird_setting(u16 cm_ird)
{
        u8 encoded_ird_size;

        /* ird_size field is encoded in qp_ctx */
        switch (cm_ird ? roundup_pow_of_two(cm_ird) : 0) {
        case I40IW_HW_IRD_SETTING_64:
                encoded_ird_size = 3;
                break;
        case I40IW_HW_IRD_SETTING_32:
        case I40IW_HW_IRD_SETTING_16:
                encoded_ird_size = 2;
                break;
        case I40IW_HW_IRD_SETTING_8:
        case I40IW_HW_IRD_SETTING_4:
                encoded_ird_size = 1;
                break;
        case I40IW_HW_IRD_SETTING_2:
        default:
                encoded_ird_size = 0;
                break;
        }
        return encoded_ird_size;
}

/**
 * i40iw_record_ird_ord - Record IRD/ORD passed in
 * @cm_node: connection's node
 * @conn_ird: connection IRD
 * @conn_ord: connection ORD
 */
static void i40iw_record_ird_ord(struct i40iw_cm_node *cm_node, u32 conn_ird,
                                 u32 conn_ord)
{
        if (conn_ird > I40IW_MAX_IRD_SIZE)
                conn_ird = I40IW_MAX_IRD_SIZE;

        if (conn_ord > I40IW_MAX_ORD_SIZE)
                conn_ord = I40IW_MAX_ORD_SIZE;
        else if (!conn_ord && cm_node->send_rdma0_op == SEND_RDMA_READ_ZERO)
                conn_ord = 1;

        cm_node->ird_size = conn_ird;
        cm_node->ord_size = conn_ord;
}

/**
 * i40iw_copy_ip_ntohl - change network to host ip
 * @dst: host ip
 * @src: big endian
 */
void i40iw_copy_ip_ntohl(u32 *dst, __be32 *src)
{
        *dst++ = ntohl(*src++);
        *dst++ = ntohl(*src++);
        *dst++ = ntohl(*src++);
        *dst = ntohl(*src);
}

/**
 * i40iw_copy_ip_htonl - change host addr to network ip
 * @dst: host ip
 * @src: little endian
 */
static inline void i40iw_copy_ip_htonl(__be32 *dst, u32 *src)
{
        *dst++ = htonl(*src++);
        *dst++ = htonl(*src++);
        *dst++ = htonl(*src++);
        *dst = htonl(*src);
}

/**
 * i40iw_fill_sockaddr4 - get addr info for passive connection
 * @cm_node: connection's node
 * @event: upper layer's cm event
 */
static inline void i40iw_fill_sockaddr4(struct i40iw_cm_node *cm_node,
                                        struct iw_cm_event *event)
{
        struct sockaddr_in *laddr = (struct sockaddr_in *)&event->local_addr;
        struct sockaddr_in *raddr = (struct sockaddr_in *)&event->remote_addr;

        laddr->sin_family = AF_INET;
        raddr->sin_family = AF_INET;

        laddr->sin_port = htons(cm_node->loc_port);
        raddr->sin_port = htons(cm_node->rem_port);

        laddr->sin_addr.s_addr = htonl(cm_node->loc_addr[0]);
        raddr->sin_addr.s_addr = htonl(cm_node->rem_addr[0]);
}

/**
 * i40iw_fill_sockaddr6 - get ipv6 addr info for passive side
 * @cm_node: connection's node
 * @event: upper layer's cm event
 */
static inline void i40iw_fill_sockaddr6(struct i40iw_cm_node *cm_node,
                                        struct iw_cm_event *event)
{
        struct sockaddr_in6 *laddr6 = (struct sockaddr_in6 *)&event->local_addr;
        struct sockaddr_in6 *raddr6 = (struct sockaddr_in6 *)&event->remote_addr;

        laddr6->sin6_family = AF_INET6;
        raddr6->sin6_family = AF_INET6;

        laddr6->sin6_port = htons(cm_node->loc_port);
        raddr6->sin6_port = htons(cm_node->rem_port);

        i40iw_copy_ip_htonl(laddr6->sin6_addr.in6_u.u6_addr32,
                            cm_node->loc_addr);
        i40iw_copy_ip_htonl(raddr6->sin6_addr.in6_u.u6_addr32,
                            cm_node->rem_addr);
}

/**
 * i40iw_get_addr_info
 * @cm_node: contains ip/tcp info
 * @cm_info: to get a copy of the cm_node ip/tcp info
*/
static void i40iw_get_addr_info(struct i40iw_cm_node *cm_node,
                                struct i40iw_cm_info *cm_info)
{
        cm_info->ipv4 = cm_node->ipv4;
        cm_info->vlan_id = cm_node->vlan_id;
        memcpy(cm_info->loc_addr, cm_node->loc_addr, sizeof(cm_info->loc_addr));
        memcpy(cm_info->rem_addr, cm_node->rem_addr, sizeof(cm_info->rem_addr));
        cm_info->loc_port = cm_node->loc_port;
        cm_info->rem_port = cm_node->rem_port;
        cm_info->user_pri = cm_node->user_pri;
}

/**
 * i40iw_get_cmevent_info - for cm event upcall
 * @cm_node: connection's node
 * @cm_id: upper layers cm struct for the event
 * @event: upper layer's cm event
 */
static inline void i40iw_get_cmevent_info(struct i40iw_cm_node *cm_node,
                                          struct iw_cm_id *cm_id,
                                          struct iw_cm_event *event)
{
        memcpy(&event->local_addr, &cm_id->m_local_addr,
               sizeof(event->local_addr));
        memcpy(&event->remote_addr, &cm_id->m_remote_addr,
               sizeof(event->remote_addr));
        if (cm_node) {
                event->private_data = (void *)cm_node->pdata_buf;
                event->private_data_len = (u8)cm_node->pdata.size;
                event->ird = cm_node->ird_size;
                event->ord = cm_node->ord_size;
        }
}

/**
 * i40iw_send_cm_event - upcall cm's event handler
 * @cm_node: connection's node
 * @cm_id: upper layer's cm info struct
 * @type: Event type to indicate
 * @status: status for the event type
 */
static int i40iw_send_cm_event(struct i40iw_cm_node *cm_node,
                               struct iw_cm_id *cm_id,
                               enum iw_cm_event_type type,
                               int status)
{
        struct iw_cm_event event;

        memset(&event, 0, sizeof(event));
        event.event = type;
        event.status = status;
        switch (type) {
        case IW_CM_EVENT_CONNECT_REQUEST:
                if (cm_node->ipv4)
                        i40iw_fill_sockaddr4(cm_node, &event);
                else
                        i40iw_fill_sockaddr6(cm_node, &event);
                event.provider_data = (void *)cm_node;
                event.private_data = (void *)cm_node->pdata_buf;
                event.private_data_len = (u8)cm_node->pdata.size;
                event.ird = cm_node->ird_size;
                break;
        case IW_CM_EVENT_CONNECT_REPLY:
                i40iw_get_cmevent_info(cm_node, cm_id, &event);
                break;
        case IW_CM_EVENT_ESTABLISHED:
                event.ird = cm_node->ird_size;
                event.ord = cm_node->ord_size;
                break;
        case IW_CM_EVENT_DISCONNECT:
                break;
        case IW_CM_EVENT_CLOSE:
                break;
        default:
                i40iw_pr_err("event type received type = %d\n", type);
                return -1;
        }
        return cm_id->event_handler(cm_id, &event);
}

/**
 * i40iw_create_event - create cm event
 * @cm_node: connection's node
 * @type: Event type to generate
 */
static struct i40iw_cm_event *i40iw_create_event(struct i40iw_cm_node *cm_node,
                                                 enum i40iw_cm_event_type type)
{
        struct i40iw_cm_event *event;

        if (!cm_node->cm_id)
                return NULL;

        event = kzalloc(sizeof(*event), GFP_ATOMIC);

        if (!event)
                return NULL;

        event->type = type;
        event->cm_node = cm_node;
        memcpy(event->cm_info.rem_addr, cm_node->rem_addr, sizeof(event->cm_info.rem_addr));
        memcpy(event->cm_info.loc_addr, cm_node->loc_addr, sizeof(event->cm_info.loc_addr));
        event->cm_info.rem_port = cm_node->rem_port;
        event->cm_info.loc_port = cm_node->loc_port;
        event->cm_info.cm_id = cm_node->cm_id;

        i40iw_debug(cm_node->dev,
                    I40IW_DEBUG_CM,
                    "node=%p event=%p type=%u dst=%pI4 src=%pI4\n",
                    cm_node,
                    event,
                    type,
                    event->cm_info.loc_addr,
                    event->cm_info.rem_addr);

        i40iw_cm_post_event(event);
        return event;
}

/**
 * i40iw_free_retrans_entry - free send entry
 * @cm_node: connection's node
 */
static void i40iw_free_retrans_entry(struct i40iw_cm_node *cm_node)
{
        struct i40iw_device *iwdev = cm_node->iwdev;
        struct i40iw_timer_entry *send_entry;

        send_entry = cm_node->send_entry;
        if (send_entry) {
                cm_node->send_entry = NULL;
                i40iw_free_sqbuf(&iwdev->vsi, (void *)send_entry->sqbuf);
                kfree(send_entry);
                atomic_dec(&cm_node->ref_count);
        }
}

/**
 * i40iw_cleanup_retrans_entry - free send entry with lock
 * @cm_node: connection's node
 */
static void i40iw_cleanup_retrans_entry(struct i40iw_cm_node *cm_node)
{
        unsigned long flags;

        spin_lock_irqsave(&cm_node->retrans_list_lock, flags);
        i40iw_free_retrans_entry(cm_node);
        spin_unlock_irqrestore(&cm_node->retrans_list_lock, flags);
}

/**
 * i40iw_form_cm_frame - get a free packet and build frame
 * @cm_node: connection's node ionfo to use in frame
 * @options: pointer to options info
 * @hdr: pointer mpa header
 * @pdata: pointer to private data
 * @flags:  indicates FIN or ACK
 */
static struct i40iw_puda_buf *i40iw_form_cm_frame(struct i40iw_cm_node *cm_node,
                                                  struct i40iw_kmem_info *options,
                                                  struct i40iw_kmem_info *hdr,
                                                  struct i40iw_kmem_info *pdata,
                                                  u8 flags)
{
        struct i40iw_puda_buf *sqbuf;
        struct i40iw_sc_vsi *vsi = &cm_node->iwdev->vsi;
        u8 *buf;

        struct tcphdr *tcph;
        struct iphdr *iph;
        struct ipv6hdr *ip6h;
        struct ethhdr *ethh;
        u16 packetsize;
        u16 eth_hlen = ETH_HLEN;
        u32 opts_len = 0;
        u32 pd_len = 0;
        u32 hdr_len = 0;
        u16 vtag;

        sqbuf = i40iw_puda_get_bufpool(vsi->ilq);
        if (!sqbuf)
                return NULL;
        buf = sqbuf->mem.va;

        if (options)
                opts_len = (u32)options->size;

        if (hdr)
                hdr_len = hdr->size;

        if (pdata)
                pd_len = pdata->size;

        if (cm_node->vlan_id < VLAN_TAG_PRESENT)
                eth_hlen += 4;

        if (cm_node->ipv4)
                packetsize = sizeof(*iph) + sizeof(*tcph);
        else
                packetsize = sizeof(*ip6h) + sizeof(*tcph);
        packetsize += opts_len + hdr_len + pd_len;

        memset(buf, 0x00, eth_hlen + packetsize);

        sqbuf->totallen = packetsize + eth_hlen;
        sqbuf->maclen = eth_hlen;
        sqbuf->tcphlen = sizeof(*tcph) + opts_len;
        sqbuf->scratch = (void *)cm_node;

        ethh = (struct ethhdr *)buf;
        buf += eth_hlen;

        if (cm_node->ipv4) {
                sqbuf->ipv4 = true;

                iph = (struct iphdr *)buf;
                buf += sizeof(*iph);
                tcph = (struct tcphdr *)buf;
                buf += sizeof(*tcph);

                ether_addr_copy(ethh->h_dest, cm_node->rem_mac);
                ether_addr_copy(ethh->h_source, cm_node->loc_mac);
                if (cm_node->vlan_id < VLAN_TAG_PRESENT) {
                        ((struct vlan_ethhdr *)ethh)->h_vlan_proto = htons(ETH_P_8021Q);
                        vtag = (cm_node->user_pri << VLAN_PRIO_SHIFT) | cm_node->vlan_id;
                        ((struct vlan_ethhdr *)ethh)->h_vlan_TCI = htons(vtag);

                        ((struct vlan_ethhdr *)ethh)->h_vlan_encapsulated_proto = htons(ETH_P_IP);
                } else {
                        ethh->h_proto = htons(ETH_P_IP);
                }

                iph->version = IPVERSION;
                iph->ihl = 5;   /* 5 * 4Byte words, IP headr len */
                iph->tos = cm_node->tos;
                iph->tot_len = htons(packetsize);
                iph->id = htons(++cm_node->tcp_cntxt.loc_id);

                iph->frag_off = htons(0x4000);
                iph->ttl = 0x40;
                iph->protocol = IPPROTO_TCP;
                iph->saddr = htonl(cm_node->loc_addr[0]);
                iph->daddr = htonl(cm_node->rem_addr[0]);
        } else {
                sqbuf->ipv4 = false;
                ip6h = (struct ipv6hdr *)buf;
                buf += sizeof(*ip6h);
                tcph = (struct tcphdr *)buf;
                buf += sizeof(*tcph);

                ether_addr_copy(ethh->h_dest, cm_node->rem_mac);
                ether_addr_copy(ethh->h_source, cm_node->loc_mac);
                if (cm_node->vlan_id < VLAN_TAG_PRESENT) {
                        ((struct vlan_ethhdr *)ethh)->h_vlan_proto = htons(ETH_P_8021Q);
                        vtag = (cm_node->user_pri << VLAN_PRIO_SHIFT) | cm_node->vlan_id;
                        ((struct vlan_ethhdr *)ethh)->h_vlan_TCI = htons(vtag);
                        ((struct vlan_ethhdr *)ethh)->h_vlan_encapsulated_proto = htons(ETH_P_IPV6);
                } else {
                        ethh->h_proto = htons(ETH_P_IPV6);
                }
                ip6h->version = 6;
                ip6h->priority = cm_node->tos >> 4;
                ip6h->flow_lbl[0] = cm_node->tos << 4;
                ip6h->flow_lbl[1] = 0;
                ip6h->flow_lbl[2] = 0;
                ip6h->payload_len = htons(packetsize - sizeof(*ip6h));
                ip6h->nexthdr = 6;
                ip6h->hop_limit = 128;
                i40iw_copy_ip_htonl(ip6h->saddr.in6_u.u6_addr32,
                                    cm_node->loc_addr);
                i40iw_copy_ip_htonl(ip6h->daddr.in6_u.u6_addr32,
                                    cm_node->rem_addr);
        }

        tcph->source = htons(cm_node->loc_port);
        tcph->dest = htons(cm_node->rem_port);

        tcph->seq = htonl(cm_node->tcp_cntxt.loc_seq_num);

        if (flags & SET_ACK) {
                cm_node->tcp_cntxt.loc_ack_num = cm_node->tcp_cntxt.rcv_nxt;
                tcph->ack_seq = htonl(cm_node->tcp_cntxt.loc_ack_num);
                tcph->ack = 1;
        } else {
                tcph->ack_seq = 0;
        }

        if (flags & SET_SYN) {
                cm_node->tcp_cntxt.loc_seq_num++;
                tcph->syn = 1;
        } else {
                cm_node->tcp_cntxt.loc_seq_num += hdr_len + pd_len;
        }

        if (flags & SET_FIN) {
                cm_node->tcp_cntxt.loc_seq_num++;
                tcph->fin = 1;
        }

        if (flags & SET_RST)
                tcph->rst = 1;

        tcph->doff = (u16)((sizeof(*tcph) + opts_len + 3) >> 2);
        sqbuf->tcphlen = tcph->doff << 2;
        tcph->window = htons(cm_node->tcp_cntxt.rcv_wnd);
        tcph->urg_ptr = 0;

        if (opts_len) {
                memcpy(buf, options->addr, opts_len);
                buf += opts_len;
        }

        if (hdr_len) {
                memcpy(buf, hdr->addr, hdr_len);
                buf += hdr_len;
        }

        if (pdata && pdata->addr)
                memcpy(buf, pdata->addr, pdata->size);

        atomic_set(&sqbuf->refcount, 1);

        return sqbuf;
}

/**
 * i40iw_send_reset - Send RST packet
 * @cm_node: connection's node
 */
int i40iw_send_reset(struct i40iw_cm_node *cm_node)
{
        struct i40iw_puda_buf *sqbuf;
        int flags = SET_RST | SET_ACK;

        sqbuf = i40iw_form_cm_frame(cm_node, NULL, NULL, NULL, flags);
        if (!sqbuf) {
                i40iw_pr_err("no sqbuf\n");
                return -1;
        }

        return i40iw_schedule_cm_timer(cm_node, sqbuf, I40IW_TIMER_TYPE_SEND, 0, 1);
}

/**
 * i40iw_active_open_err - send event for active side cm error
 * @cm_node: connection's node
 * @reset: Flag to send reset or not
 */
static void i40iw_active_open_err(struct i40iw_cm_node *cm_node, bool reset)
{
        i40iw_cleanup_retrans_entry(cm_node);
        cm_node->cm_core->stats_connect_errs++;
        if (reset) {
                i40iw_debug(cm_node->dev,
                            I40IW_DEBUG_CM,
                            "%s cm_node=%p state=%d\n",
                            __func__,
                            cm_node,
                            cm_node->state);
                atomic_inc(&cm_node->ref_count);
                i40iw_send_reset(cm_node);
        }

        cm_node->state = I40IW_CM_STATE_CLOSED;
        i40iw_create_event(cm_node, I40IW_CM_EVENT_ABORTED);
}

/**
 * i40iw_passive_open_err - handle passive side cm error
 * @cm_node: connection's node
 * @reset: send reset or just free cm_node
 */
static void i40iw_passive_open_err(struct i40iw_cm_node *cm_node, bool reset)
{
        i40iw_cleanup_retrans_entry(cm_node);
        cm_node->cm_core->stats_passive_errs++;
        cm_node->state = I40IW_CM_STATE_CLOSED;
        i40iw_debug(cm_node->dev,
                    I40IW_DEBUG_CM,
                    "%s cm_node=%p state =%d\n",
                    __func__,
                    cm_node,
                    cm_node->state);
        if (reset)
                i40iw_send_reset(cm_node);
        else
                i40iw_rem_ref_cm_node(cm_node);
}

/**
 * i40iw_event_connect_error - to create connect error event
 * @event: cm information for connect event
 */
static void i40iw_event_connect_error(struct i40iw_cm_event *event)
{
        struct i40iw_qp *iwqp;
        struct iw_cm_id *cm_id;

        cm_id = event->cm_node->cm_id;
        if (!cm_id)
                return;

        iwqp = cm_id->provider_data;

        if (!iwqp || !iwqp->iwdev)
                return;

        iwqp->cm_id = NULL;
        cm_id->provider_data = NULL;
        i40iw_send_cm_event(event->cm_node, cm_id,
                            IW_CM_EVENT_CONNECT_REPLY,
                            -ECONNRESET);
        cm_id->rem_ref(cm_id);
        i40iw_rem_ref_cm_node(event->cm_node);
}

/**
 * i40iw_process_options
 * @cm_node: connection's node
 * @optionsloc: point to start of options
 * @optionsize: size of all options
 * @syn_packet: flag if syn packet
 */
static int i40iw_process_options(struct i40iw_cm_node *cm_node,
                                 u8 *optionsloc,
                                 u32 optionsize,
                                 u32 syn_packet)
{
        u32 tmp;
        u32 offset = 0;
        union all_known_options *all_options;
        char got_mss_option = 0;

        while (offset < optionsize) {
                all_options = (union all_known_options *)(optionsloc + offset);
                switch (all_options->as_base.optionnum) {
                case OPTION_NUMBER_END:
                        offset = optionsize;
                        break;
                case OPTION_NUMBER_NONE:
                        offset += 1;
                        continue;
                case OPTION_NUMBER_MSS:
                        i40iw_debug(cm_node->dev,
                                    I40IW_DEBUG_CM,
                                    "%s: MSS Length: %d Offset: %d Size: %d\n",
                                    __func__,
                                    all_options->as_mss.length,
                                    offset,
                                    optionsize);
                        got_mss_option = 1;
                        if (all_options->as_mss.length != 4)
                                return -1;
                        tmp = ntohs(all_options->as_mss.mss);
                        if (tmp > 0 && tmp < cm_node->tcp_cntxt.mss)
                                cm_node->tcp_cntxt.mss = tmp;
                        break;
                case OPTION_NUMBER_WINDOW_SCALE:
                        cm_node->tcp_cntxt.snd_wscale =
                            all_options->as_windowscale.shiftcount;
                        break;
                default:
                        i40iw_debug(cm_node->dev,
                                    I40IW_DEBUG_CM,
                                    "TCP Option not understood: %x\n",
                                    all_options->as_base.optionnum);
                        break;
                }
                offset += all_options->as_base.length;
        }
        if (!got_mss_option && syn_packet)
                cm_node->tcp_cntxt.mss = I40IW_CM_DEFAULT_MSS;
        return 0;
}

/**
 * i40iw_handle_tcp_options -
 * @cm_node: connection's node
 * @tcph: pointer tcp header
 * @optionsize: size of options rcvd
 * @passive: active or passive flag
 */
static int i40iw_handle_tcp_options(struct i40iw_cm_node *cm_node,
                                    struct tcphdr *tcph,
                                    int optionsize,
                                    int passive)
{
        u8 *optionsloc = (u8 *)&tcph[1];

        if (optionsize) {
                if (i40iw_process_options(cm_node,
                                          optionsloc,
                                          optionsize,
                                          (u32)tcph->syn)) {
                        i40iw_debug(cm_node->dev,
                                    I40IW_DEBUG_CM,
                                    "%s: Node %p, Sending RESET\n",
                                    __func__,
                                    cm_node);
                        if (passive)
                                i40iw_passive_open_err(cm_node, true);
                        else
                                i40iw_active_open_err(cm_node, true);
                        return -1;
                }
        }

        cm_node->tcp_cntxt.snd_wnd = ntohs(tcph->window) <<
            cm_node->tcp_cntxt.snd_wscale;

        if (cm_node->tcp_cntxt.snd_wnd > cm_node->tcp_cntxt.max_snd_wnd)
                cm_node->tcp_cntxt.max_snd_wnd = cm_node->tcp_cntxt.snd_wnd;
        return 0;
}

/**
 * i40iw_build_mpa_v1 - build a MPA V1 frame
 * @cm_node: connection's node
 * @mpa_key: to do read0 or write0
 */
static void i40iw_build_mpa_v1(struct i40iw_cm_node *cm_node,
                               void *start_addr,
                               u8 mpa_key)
{
        struct ietf_mpa_v1 *mpa_frame = (struct ietf_mpa_v1 *)start_addr;

        switch (mpa_key) {
        case MPA_KEY_REQUEST:
                memcpy(mpa_frame->key, IEFT_MPA_KEY_REQ, IETF_MPA_KEY_SIZE);
                break;
        case MPA_KEY_REPLY:
                memcpy(mpa_frame->key, IEFT_MPA_KEY_REP, IETF_MPA_KEY_SIZE);
                break;
        default:
                break;
        }
        mpa_frame->flags = IETF_MPA_FLAGS_CRC;
        mpa_frame->rev = cm_node->mpa_frame_rev;
        mpa_frame->priv_data_len = htons(cm_node->pdata.size);
}

/**
 * i40iw_build_mpa_v2 - build a MPA V2 frame
 * @cm_node: connection's node
 * @start_addr: buffer start address
 * @mpa_key: to do read0 or write0
 */
static void i40iw_build_mpa_v2(struct i40iw_cm_node *cm_node,
                               void *start_addr,
                               u8 mpa_key)
{
        struct ietf_mpa_v2 *mpa_frame = (struct ietf_mpa_v2 *)start_addr;
        struct ietf_rtr_msg *rtr_msg = &mpa_frame->rtr_msg;
        u16 ctrl_ird, ctrl_ord;

        /* initialize the upper 5 bytes of the frame */
        i40iw_build_mpa_v1(cm_node, start_addr, mpa_key);
        mpa_frame->flags |= IETF_MPA_V2_FLAG;
        mpa_frame->priv_data_len += htons(IETF_RTR_MSG_SIZE);

        /* initialize RTR msg */
        if (cm_node->mpav2_ird_ord == IETF_NO_IRD_ORD) {
                ctrl_ird = IETF_NO_IRD_ORD;
                ctrl_ord = IETF_NO_IRD_ORD;
        } else {
                ctrl_ird = (cm_node->ird_size > IETF_NO_IRD_ORD) ?
                        IETF_NO_IRD_ORD : cm_node->ird_size;
                ctrl_ord = (cm_node->ord_size > IETF_NO_IRD_ORD) ?
                        IETF_NO_IRD_ORD : cm_node->ord_size;
        }

        ctrl_ird |= IETF_PEER_TO_PEER;

        switch (mpa_key) {
        case MPA_KEY_REQUEST:
                ctrl_ord |= IETF_RDMA0_WRITE;
                ctrl_ord |= IETF_RDMA0_READ;
                break;
        case MPA_KEY_REPLY:
                switch (cm_node->send_rdma0_op) {
                case SEND_RDMA_WRITE_ZERO:
                        ctrl_ord |= IETF_RDMA0_WRITE;
                        break;
                case SEND_RDMA_READ_ZERO:
                        ctrl_ord |= IETF_RDMA0_READ;
                        break;
                }
                break;
        default:
                break;
        }
        rtr_msg->ctrl_ird = htons(ctrl_ird);
        rtr_msg->ctrl_ord = htons(ctrl_ord);
}

/**
 * i40iw_cm_build_mpa_frame - build mpa frame for mpa version 1 or version 2
 * @cm_node: connection's node
 * @mpa: mpa: data buffer
 * @mpa_key: to do read0 or write0
 */
static int i40iw_cm_build_mpa_frame(struct i40iw_cm_node *cm_node,
                                    struct i40iw_kmem_info *mpa,
                                    u8 mpa_key)
{
        int hdr_len = 0;

        switch (cm_node->mpa_frame_rev) {
        case IETF_MPA_V1:
                hdr_len = sizeof(struct ietf_mpa_v1);
                i40iw_build_mpa_v1(cm_node, mpa->addr, mpa_key);
                break;
        case IETF_MPA_V2:
                hdr_len = sizeof(struct ietf_mpa_v2);
                i40iw_build_mpa_v2(cm_node, mpa->addr, mpa_key);
                break;
        default:
                break;
        }

        return hdr_len;
}

/**
 * i40iw_send_mpa_request - active node send mpa request to passive node
 * @cm_node: connection's node
 */
static int i40iw_send_mpa_request(struct i40iw_cm_node *cm_node)
{
        struct i40iw_puda_buf *sqbuf;

        if (!cm_node) {
                i40iw_pr_err("cm_node == NULL\n");
                return -1;
        }

        cm_node->mpa_hdr.addr = &cm_node->mpa_frame;
        cm_node->mpa_hdr.size = i40iw_cm_build_mpa_frame(cm_node,
                                                         &cm_node->mpa_hdr,
                                                         MPA_KEY_REQUEST);
        if (!cm_node->mpa_hdr.size) {
                i40iw_pr_err("mpa size = %d\n", cm_node->mpa_hdr.size);
                return -1;
        }

        sqbuf = i40iw_form_cm_frame(cm_node,
                                    NULL,
                                    &cm_node->mpa_hdr,
                                    &cm_node->pdata,
                                    SET_ACK);
        if (!sqbuf) {
                i40iw_pr_err("sq_buf == NULL\n");
                return -1;
        }
        return i40iw_schedule_cm_timer(cm_node, sqbuf, I40IW_TIMER_TYPE_SEND, 1, 0);
}

/**
 * i40iw_send_mpa_reject -
 * @cm_node: connection's node
 * @pdata: reject data for connection
 * @plen: length of reject data
 */
static int i40iw_send_mpa_reject(struct i40iw_cm_node *cm_node,
                                 const void *pdata,
                                 u8 plen)
{
        struct i40iw_puda_buf *sqbuf;
        struct i40iw_kmem_info priv_info;

        cm_node->mpa_hdr.addr = &cm_node->mpa_frame;
        cm_node->mpa_hdr.size = i40iw_cm_build_mpa_frame(cm_node,
                                                         &cm_node->mpa_hdr,
                                                         MPA_KEY_REPLY);

        cm_node->mpa_frame.flags |= IETF_MPA_FLAGS_REJECT;
        priv_info.addr = (void *)pdata;
        priv_info.size = plen;

        sqbuf = i40iw_form_cm_frame(cm_node,
                                    NULL,
                                    &cm_node->mpa_hdr,
                                    &priv_info,
                                    SET_ACK | SET_FIN);
        if (!sqbuf) {
                i40iw_pr_err("no sqbuf\n");
                return -ENOMEM;
        }
        cm_node->state = I40IW_CM_STATE_FIN_WAIT1;
        return i40iw_schedule_cm_timer(cm_node, sqbuf, I40IW_TIMER_TYPE_SEND, 1, 0);
}

/**
 * recv_mpa - process an IETF MPA frame
 * @cm_node: connection's node
 * @buffer: Data pointer
 * @type: to return accept or reject
 * @len: Len of mpa buffer
 */
static int i40iw_parse_mpa(struct i40iw_cm_node *cm_node, u8 *buffer, u32 *type, u32 len)
{
        struct ietf_mpa_v1 *mpa_frame;
        struct ietf_mpa_v2 *mpa_v2_frame;
        struct ietf_rtr_msg *rtr_msg;
        int mpa_hdr_len;
        int priv_data_len;

        *type = I40IW_MPA_REQUEST_ACCEPT;

        if (len < sizeof(struct ietf_mpa_v1)) {
                i40iw_pr_err("ietf buffer small (%x)\n", len);
                return -1;
        }

        mpa_frame = (struct ietf_mpa_v1 *)buffer;
        mpa_hdr_len = sizeof(struct ietf_mpa_v1);
        priv_data_len = ntohs(mpa_frame->priv_data_len);

        if (priv_data_len > IETF_MAX_PRIV_DATA_LEN) {
                i40iw_pr_err("large pri_data %d\n", priv_data_len);
                return -1;
        }
        if (mpa_frame->rev != IETF_MPA_V1 && mpa_frame->rev != IETF_MPA_V2) {
                i40iw_pr_err("unsupported mpa rev = %d\n", mpa_frame->rev);
                return -1;
        }
        if (mpa_frame->rev > cm_node->mpa_frame_rev) {
                i40iw_pr_err("rev %d\n", mpa_frame->rev);
                return -1;
        }
        cm_node->mpa_frame_rev = mpa_frame->rev;

        if (cm_node->state != I40IW_CM_STATE_MPAREQ_SENT) {
                if (memcmp(mpa_frame->key, IEFT_MPA_KEY_REQ, IETF_MPA_KEY_SIZE)) {
                        i40iw_pr_err("Unexpected MPA Key received\n");
                        return -1;
                }
        } else {
                if (memcmp(mpa_frame->key, IEFT_MPA_KEY_REP, IETF_MPA_KEY_SIZE)) {
                        i40iw_pr_err("Unexpected MPA Key received\n");
                        return -1;
                }
        }

        if (priv_data_len + mpa_hdr_len > len) {
                i40iw_pr_err("ietf buffer len(%x + %x != %x)\n",
                             priv_data_len, mpa_hdr_len, len);
                return -1;
        }
        if (len > MAX_CM_BUFFER) {
                i40iw_pr_err("ietf buffer large len = %d\n", len);
                return -1;
        }

        switch (mpa_frame->rev) {
        case IETF_MPA_V2:{
                        u16 ird_size;
                        u16 ord_size;
                        u16 ctrl_ord;
                        u16 ctrl_ird;

                        mpa_v2_frame = (struct ietf_mpa_v2 *)buffer;
                        mpa_hdr_len += IETF_RTR_MSG_SIZE;
                        rtr_msg = &mpa_v2_frame->rtr_msg;

                        /* parse rtr message */
                        ctrl_ord = ntohs(rtr_msg->ctrl_ord);
                        ctrl_ird = ntohs(rtr_msg->ctrl_ird);
                        ird_size = ctrl_ird & IETF_NO_IRD_ORD;
                        ord_size = ctrl_ord & IETF_NO_IRD_ORD;

                        if (!(ctrl_ird & IETF_PEER_TO_PEER))
                                return -1;

                        if (ird_size == IETF_NO_IRD_ORD || ord_size == IETF_NO_IRD_ORD) {
                                cm_node->mpav2_ird_ord = IETF_NO_IRD_ORD;
                                goto negotiate_done;
                        }

                        if (cm_node->state != I40IW_CM_STATE_MPAREQ_SENT) {
                                /* responder */
                                if (!ord_size && (ctrl_ord & IETF_RDMA0_READ))
                                        cm_node->ird_size = 1;
                                if (cm_node->ord_size > ird_size)
                                        cm_node->ord_size = ird_size;
                        } else {
                                /* initiator */

                                if (!ird_size && (ctrl_ord & IETF_RDMA0_READ))
                                        return -1;
                                if (cm_node->ord_size > ird_size)
                                        cm_node->ord_size = ird_size;

                                if (cm_node->ird_size < ord_size)
                                        /* no resources available */
                                        return -1;
                        }

negotiate_done:
                        if (ctrl_ord & IETF_RDMA0_READ)
                                cm_node->send_rdma0_op = SEND_RDMA_READ_ZERO;
                        else if (ctrl_ord & IETF_RDMA0_WRITE)
                                cm_node->send_rdma0_op = SEND_RDMA_WRITE_ZERO;
                        else    /* Not supported RDMA0 operation */
                                return -1;
                        i40iw_debug(cm_node->dev, I40IW_DEBUG_CM,
                                    "MPAV2: Negotiated ORD: %d, IRD: %d\n",
                                    cm_node->ord_size, cm_node->ird_size);
                        break;
                }
                break;
        case IETF_MPA_V1:
        default:
                break;
        }

        memcpy(cm_node->pdata_buf, buffer + mpa_hdr_len, priv_data_len);
        cm_node->pdata.size = priv_data_len;

        if (mpa_frame->flags & IETF_MPA_FLAGS_REJECT)
                *type = I40IW_MPA_REQUEST_REJECT;

        if (mpa_frame->flags & IETF_MPA_FLAGS_MARKERS)
                cm_node->snd_mark_en = true;

        return 0;
}

/**
 * i40iw_schedule_cm_timer
 * @@cm_node: connection's node
 * @sqbuf: buffer to send
 * @type: if it is send or close
 * @send_retrans: if rexmits to be done
 * @close_when_complete: is cm_node to be removed
 *
 * note - cm_node needs to be protected before calling this. Encase in:
 *              i40iw_rem_ref_cm_node(cm_core, cm_node);
 *              i40iw_schedule_cm_timer(...)
 *              atomic_inc(&cm_node->ref_count);
 */
int i40iw_schedule_cm_timer(struct i40iw_cm_node *cm_node,
                            struct i40iw_puda_buf *sqbuf,
                            enum i40iw_timer_type type,
                            int send_retrans,
                            int close_when_complete)
{
        struct i40iw_sc_vsi *vsi = &cm_node->iwdev->vsi;
        struct i40iw_cm_core *cm_core = cm_node->cm_core;
        struct i40iw_timer_entry *new_send;
        int ret = 0;
        u32 was_timer_set;
        unsigned long flags;

        new_send = kzalloc(sizeof(*new_send), GFP_ATOMIC);
        if (!new_send) {
                if (type != I40IW_TIMER_TYPE_CLOSE)
                        i40iw_free_sqbuf(vsi, (void *)sqbuf);
                return -ENOMEM;
        }
        new_send->retrycount = I40IW_DEFAULT_RETRYS;
        new_send->retranscount = I40IW_DEFAULT_RETRANS;
        new_send->sqbuf = sqbuf;
        new_send->timetosend = jiffies;
        new_send->type = type;
        new_send->send_retrans = send_retrans;
        new_send->close_when_complete = close_when_complete;

        if (type == I40IW_TIMER_TYPE_CLOSE) {
                new_send->timetosend += (HZ / 10);
                if (cm_node->close_entry) {
                        kfree(new_send);
                        i40iw_pr_err("already close entry\n");
                        return -EINVAL;
                }
                cm_node->close_entry = new_send;
        }

        if (type == I40IW_TIMER_TYPE_SEND) {
                spin_lock_irqsave(&cm_node->retrans_list_lock, flags);
                cm_node->send_entry = new_send;
                atomic_inc(&cm_node->ref_count);
                spin_unlock_irqrestore(&cm_node->retrans_list_lock, flags);
                new_send->timetosend = jiffies + I40IW_RETRY_TIMEOUT;

                atomic_inc(&sqbuf->refcount);
                i40iw_puda_send_buf(vsi->ilq, sqbuf);
                if (!send_retrans) {
                        i40iw_cleanup_retrans_entry(cm_node);
                        if (close_when_complete)
                                i40iw_rem_ref_cm_node(cm_node);
                        return ret;
                }
        }

        spin_lock_irqsave(&cm_core->ht_lock, flags);
        was_timer_set = timer_pending(&cm_core->tcp_timer);

        if (!was_timer_set) {
                cm_core->tcp_timer.expires = new_send->timetosend;
                add_timer(&cm_core->tcp_timer);
        }
        spin_unlock_irqrestore(&cm_core->ht_lock, flags);

        return ret;
}

/**
 * i40iw_retrans_expired - Could not rexmit the packet
 * @cm_node: connection's node
 */
static void i40iw_retrans_expired(struct i40iw_cm_node *cm_node)
{
        struct iw_cm_id *cm_id = cm_node->cm_id;
        enum i40iw_cm_node_state state = cm_node->state;

        cm_node->state = I40IW_CM_STATE_CLOSED;
        switch (state) {
        case I40IW_CM_STATE_SYN_RCVD:
        case I40IW_CM_STATE_CLOSING:
                i40iw_rem_ref_cm_node(cm_node);
                break;
        case I40IW_CM_STATE_FIN_WAIT1:
        case I40IW_CM_STATE_LAST_ACK:
                if (cm_node->cm_id)
                        cm_id->rem_ref(cm_id);
                i40iw_send_reset(cm_node);
                break;
        default:
                atomic_inc(&cm_node->ref_count);
                i40iw_send_reset(cm_node);
                i40iw_create_event(cm_node, I40IW_CM_EVENT_ABORTED);
                break;
        }
}

/**
 * i40iw_handle_close_entry - for handling retry/timeouts
 * @cm_node: connection's node
 * @rem_node: flag for remove cm_node
 */
static void i40iw_handle_close_entry(struct i40iw_cm_node *cm_node, u32 rem_node)
{
        struct i40iw_timer_entry *close_entry = cm_node->close_entry;
        struct iw_cm_id *cm_id = cm_node->cm_id;
        struct i40iw_qp *iwqp;
        unsigned long flags;

        if (!close_entry)
                return;
        iwqp = (struct i40iw_qp *)close_entry->sqbuf;
        if (iwqp) {
                spin_lock_irqsave(&iwqp->lock, flags);
                if (iwqp->cm_id) {
                        iwqp->hw_tcp_state = I40IW_TCP_STATE_CLOSED;
                        iwqp->hw_iwarp_state = I40IW_QP_STATE_ERROR;
                        iwqp->last_aeq = I40IW_AE_RESET_SENT;
                        iwqp->ibqp_state = IB_QPS_ERR;
                        spin_unlock_irqrestore(&iwqp->lock, flags);
                        i40iw_cm_disconn(iwqp);
                } else {
                        spin_unlock_irqrestore(&iwqp->lock, flags);
                }
        } else if (rem_node) {
                /* TIME_WAIT state */
                i40iw_rem_ref_cm_node(cm_node);
        }
        if (cm_id)
                cm_id->rem_ref(cm_id);
        kfree(close_entry);
        cm_node->close_entry = NULL;
}

/**
 * i40iw_build_timer_list - Add cm_nodes to timer list
 * @timer_list: ptr to timer list
 * @hte: ptr to accelerated or non-accelerated list
 */
static void i40iw_build_timer_list(struct list_head *timer_list,
                                   struct list_head *hte)
{
        struct i40iw_cm_node *cm_node;
        struct list_head *list_core_temp, *list_node;

        list_for_each_safe(list_node, list_core_temp, hte) {
                cm_node = container_of(list_node, struct i40iw_cm_node, list);
                if (cm_node->close_entry || cm_node->send_entry) {
                        atomic_inc(&cm_node->ref_count);
                        list_add(&cm_node->timer_entry, timer_list);
                }
        }
}

/**
 * i40iw_cm_timer_tick - system's timer expired callback
 * @pass: Pointing to cm_core
 */
static void i40iw_cm_timer_tick(struct timer_list *t)
{
        unsigned long nexttimeout = jiffies + I40IW_LONG_TIME;
        struct i40iw_cm_node *cm_node;
        struct i40iw_timer_entry *send_entry, *close_entry;
        struct list_head *list_core_temp;
        struct i40iw_sc_vsi *vsi;
        struct list_head *list_node;
        struct i40iw_cm_core *cm_core = from_timer(cm_core, t, tcp_timer);
        u32 settimer = 0;
        unsigned long timetosend;
        unsigned long flags;

        struct list_head timer_list;

        INIT_LIST_HEAD(&timer_list);

        spin_lock_irqsave(&cm_core->ht_lock, flags);
        i40iw_build_timer_list(&timer_list, &cm_core->non_accelerated_list);
        i40iw_build_timer_list(&timer_list, &cm_core->accelerated_list);
        spin_unlock_irqrestore(&cm_core->ht_lock, flags);

        list_for_each_safe(list_node, list_core_temp, &timer_list) {
                cm_node = container_of(list_node,
                                       struct i40iw_cm_node,
                                       timer_entry);
                close_entry = cm_node->close_entry;

                if (close_entry) {
                        if (time_after(close_entry->timetosend, jiffies)) {
                                if (nexttimeout > close_entry->timetosend ||
                                    !settimer) {
                                        nexttimeout = close_entry->timetosend;
                                        settimer = 1;
                                }
                        } else {
                                i40iw_handle_close_entry(cm_node, 1);
                        }
                }

                spin_lock_irqsave(&cm_node->retrans_list_lock, flags);

                send_entry = cm_node->send_entry;
                if (!send_entry)
                        goto done;
                if (time_after(send_entry->timetosend, jiffies)) {
                        if (cm_node->state != I40IW_CM_STATE_OFFLOADED) {
                                if ((nexttimeout > send_entry->timetosend) ||
                                    !settimer) {
                                        nexttimeout = send_entry->timetosend;
                                        settimer = 1;
                                }
                        } else {
                                i40iw_free_retrans_entry(cm_node);
                        }
                        goto done;
                }

                if ((cm_node->state == I40IW_CM_STATE_OFFLOADED) ||
                    (cm_node->state == I40IW_CM_STATE_CLOSED)) {
                        i40iw_free_retrans_entry(cm_node);
                        goto done;
                }

                if (!send_entry->retranscount || !send_entry->retrycount) {
                        i40iw_free_retrans_entry(cm_node);

                        spin_unlock_irqrestore(&cm_node->retrans_list_lock, flags);
                        i40iw_retrans_expired(cm_node);
                        cm_node->state = I40IW_CM_STATE_CLOSED;
                        spin_lock_irqsave(&cm_node->retrans_list_lock, flags);
                        goto done;
                }
                spin_unlock_irqrestore(&cm_node->retrans_list_lock, flags);

                vsi = &cm_node->iwdev->vsi;

                if (!cm_node->ack_rcvd) {
                        atomic_inc(&send_entry->sqbuf->refcount);
                        i40iw_puda_send_buf(vsi->ilq, send_entry->sqbuf);
                        cm_node->cm_core->stats_pkt_retrans++;
                }
                spin_lock_irqsave(&cm_node->retrans_list_lock, flags);
                if (send_entry->send_retrans) {
                        send_entry->retranscount--;
                        timetosend = (I40IW_RETRY_TIMEOUT <<
                                      (I40IW_DEFAULT_RETRANS -
                                       send_entry->retranscount));

                        send_entry->timetosend = jiffies +
                            min(timetosend, I40IW_MAX_TIMEOUT);
                        if (nexttimeout > send_entry->timetosend || !settimer) {
                                nexttimeout = send_entry->timetosend;
                                settimer = 1;
                        }
                } else {
                        int close_when_complete;

                        close_when_complete = send_entry->close_when_complete;
                        i40iw_debug(cm_node->dev,
                                    I40IW_DEBUG_CM,
                                    "cm_node=%p state=%d\n",
                                    cm_node,
                                    cm_node->state);
                        i40iw_free_retrans_entry(cm_node);
                        if (close_when_complete)
                                i40iw_rem_ref_cm_node(cm_node);
                }
done:
                spin_unlock_irqrestore(&cm_node->retrans_list_lock, flags);
                i40iw_rem_ref_cm_node(cm_node);
        }

        if (settimer) {
                spin_lock_irqsave(&cm_core->ht_lock, flags);
                if (!timer_pending(&cm_core->tcp_timer)) {
                        cm_core->tcp_timer.expires = nexttimeout;
                        add_timer(&cm_core->tcp_timer);
                }
                spin_unlock_irqrestore(&cm_core->ht_lock, flags);
        }
}

/**
 * i40iw_send_syn - send SYN packet
 * @cm_node: connection's node
 * @sendack: flag to set ACK bit or not
 */
int i40iw_send_syn(struct i40iw_cm_node *cm_node, u32 sendack)
{
        struct i40iw_puda_buf *sqbuf;
        int flags = SET_SYN;
        char optionsbuffer[sizeof(struct option_mss) +
                           sizeof(struct option_windowscale) +
                           sizeof(struct option_base) + TCP_OPTIONS_PADDING];
        struct i40iw_kmem_info opts;

        int optionssize = 0;
        /* Sending MSS option */
        union all_known_options *options;

        opts.addr = optionsbuffer;
        if (!cm_node) {
                i40iw_pr_err("no cm_node\n");
                return -EINVAL;
        }

        options = (union all_known_options *)&optionsbuffer[optionssize];
        options->as_mss.optionnum = OPTION_NUMBER_MSS;
        options->as_mss.length = sizeof(struct option_mss);
        options->as_mss.mss = htons(cm_node->tcp_cntxt.mss);
        optionssize += sizeof(struct option_mss);

        options = (union all_known_options *)&optionsbuffer[optionssize];
        options->as_windowscale.optionnum = OPTION_NUMBER_WINDOW_SCALE;
        options->as_windowscale.length = sizeof(struct option_windowscale);
        options->as_windowscale.shiftcount = cm_node->tcp_cntxt.rcv_wscale;
        optionssize += sizeof(struct option_windowscale);
        options = (union all_known_options *)&optionsbuffer[optionssize];
        options->as_end = OPTION_NUMBER_END;
        optionssize += 1;

        if (sendack)
                flags |= SET_ACK;

        opts.size = optionssize;

        sqbuf = i40iw_form_cm_frame(cm_node, &opts, NULL, NULL, flags);
        if (!sqbuf) {
                i40iw_pr_err("no sqbuf\n");
                return -1;
        }
        return i40iw_schedule_cm_timer(cm_node, sqbuf, I40IW_TIMER_TYPE_SEND, 1, 0);
}

/**
 * i40iw_send_ack - Send ACK packet
 * @cm_node: connection's node
 */
static void i40iw_send_ack(struct i40iw_cm_node *cm_node)
{
        struct i40iw_puda_buf *sqbuf;
        struct i40iw_sc_vsi *vsi = &cm_node->iwdev->vsi;

        sqbuf = i40iw_form_cm_frame(cm_node, NULL, NULL, NULL, SET_ACK);
        if (sqbuf)
                i40iw_puda_send_buf(vsi->ilq, sqbuf);
        else
                i40iw_pr_err("no sqbuf\n");
}

/**
 * i40iw_send_fin - Send FIN pkt
 * @cm_node: connection's node
 */
static int i40iw_send_fin(struct i40iw_cm_node *cm_node)
{
        struct i40iw_puda_buf *sqbuf;

        sqbuf = i40iw_form_cm_frame(cm_node, NULL, NULL, NULL, SET_ACK | SET_FIN);
        if (!sqbuf) {
                i40iw_pr_err("no sqbuf\n");
                return -1;
        }
        return i40iw_schedule_cm_timer(cm_node, sqbuf, I40IW_TIMER_TYPE_SEND, 1, 0);
}

/**
 * i40iw_find_node - find a cm node that matches the reference cm node
 * @cm_core: cm's core
 * @rem_port: remote tcp port num
 * @rem_addr: remote ip addr
 * @loc_port: local tcp port num
 * @loc_addr: loc ip addr
 * @add_refcnt: flag to increment refcount of cm_node
 * @accelerated_list: flag for accelerated vs non-accelerated list to search
 */
struct i40iw_cm_node *i40iw_find_node(struct i40iw_cm_core *cm_core,
                                      u16 rem_port,
                                      u32 *rem_addr,
                                      u16 loc_port,
                                      u32 *loc_addr,
                                      bool add_refcnt,
                                      bool accelerated_list)
{
        struct list_head *hte;
        struct i40iw_cm_node *cm_node;
        unsigned long flags;

        hte = accelerated_list ?
              &cm_core->accelerated_list : &cm_core->non_accelerated_list;

        /* walk list and find cm_node associated with this session ID */
        spin_lock_irqsave(&cm_core->ht_lock, flags);
        list_for_each_entry(cm_node, hte, list) {
                if (!memcmp(cm_node->loc_addr, loc_addr, sizeof(cm_node->loc_addr)) &&
                    (cm_node->loc_port == loc_port) &&
                    !memcmp(cm_node->rem_addr, rem_addr, sizeof(cm_node->rem_addr)) &&
                    (cm_node->rem_port == rem_port)) {
                        if (add_refcnt)
                                atomic_inc(&cm_node->ref_count);
                        spin_unlock_irqrestore(&cm_core->ht_lock, flags);
                        return cm_node;
                }
        }
        spin_unlock_irqrestore(&cm_core->ht_lock, flags);

        /* no owner node */
        return NULL;
}

/**
 * i40iw_find_listener - find a cm node listening on this addr-port pair
 * @cm_core: cm's core
 * @dst_port: listener tcp port num
 * @dst_addr: listener ip addr
 * @listener_state: state to match with listen node's
 */
static struct i40iw_cm_listener *i40iw_find_listener(
                                                     struct i40iw_cm_core *cm_core,
                                                     u32 *dst_addr,
                                                     u16 dst_port,
                                                     u16 vlan_id,
                                                     enum i40iw_cm_listener_state
                                                     listener_state)
{
        struct i40iw_cm_listener *listen_node;
        static const u32 ip_zero[4] = { 0, 0, 0, 0 };
        u32 listen_addr[4];
        u16 listen_port;
        unsigned long flags;

        /* walk list and find cm_node associated with this session ID */
        spin_lock_irqsave(&cm_core->listen_list_lock, flags);
        list_for_each_entry(listen_node, &cm_core->listen_nodes, list) {
                memcpy(listen_addr, listen_node->loc_addr, sizeof(listen_addr));
                listen_port = listen_node->loc_port;
                /* compare node pair, return node handle if a match */
                if ((!memcmp(listen_addr, dst_addr, sizeof(listen_addr)) ||
                     !memcmp(listen_addr, ip_zero, sizeof(listen_addr))) &&
                     (listen_port == dst_port) &&
                     (listener_state & listen_node->listener_state)) {
                        atomic_inc(&listen_node->ref_count);
                        spin_unlock_irqrestore(&cm_core->listen_list_lock, flags);
                        return listen_node;
                }
        }
        spin_unlock_irqrestore(&cm_core->listen_list_lock, flags);
        return NULL;
}

/**
 * i40iw_add_hte_node - add a cm node to the hash table
 * @cm_core: cm's core
 * @cm_node: connection's node
 */
static void i40iw_add_hte_node(struct i40iw_cm_core *cm_core,
                               struct i40iw_cm_node *cm_node)
{
        unsigned long flags;

        if (!cm_node || !cm_core) {
                i40iw_pr_err("cm_node or cm_core == NULL\n");
                return;
        }

        spin_lock_irqsave(&cm_core->ht_lock, flags);
        list_add_tail(&cm_node->list, &cm_core->non_accelerated_list);
        spin_unlock_irqrestore(&cm_core->ht_lock, flags);
}

/**
 * i40iw_find_port - find port that matches reference port
 * @hte: ptr to accelerated or non-accelerated list
 * @accelerated_list: flag for accelerated vs non-accelerated list
 */
static bool i40iw_find_port(struct list_head *hte, u16 port)
{
        struct i40iw_cm_node *cm_node;

        list_for_each_entry(cm_node, hte, list) {
                if (cm_node->loc_port == port)
                        return true;
        }
        return false;
}

/**
 * i40iw_port_in_use - determine if port is in use
 * @cm_core: cm's core
 * @port: port number
 */
bool i40iw_port_in_use(struct i40iw_cm_core *cm_core, u16 port)
{
        struct i40iw_cm_listener *listen_node;
        unsigned long flags;

        spin_lock_irqsave(&cm_core->ht_lock, flags);
        if (i40iw_find_port(&cm_core->accelerated_list, port) ||
            i40iw_find_port(&cm_core->non_accelerated_list, port)) {
                spin_unlock_irqrestore(&cm_core->ht_lock, flags);
                return true;
        }
        spin_unlock_irqrestore(&cm_core->ht_lock, flags);

        spin_lock_irqsave(&cm_core->listen_list_lock, flags);
        list_for_each_entry(listen_node, &cm_core->listen_nodes, list) {
                if (listen_node->loc_port == port) {
                        spin_unlock_irqrestore(&cm_core->listen_list_lock, flags);
                        return true;
                }
        }
        spin_unlock_irqrestore(&cm_core->listen_list_lock, flags);

        return false;
}

/**
 * i40iw_del_multiple_qhash - Remove qhash and child listens
 * @iwdev: iWarp device
 * @cm_info: CM info for parent listen node
 * @cm_parent_listen_node: The parent listen node
 */
static enum i40iw_status_code i40iw_del_multiple_qhash(
                                                       struct i40iw_device *iwdev,
                                                       struct i40iw_cm_info *cm_info,
                                                       struct i40iw_cm_listener *cm_parent_listen_node)
{
        struct i40iw_cm_listener *child_listen_node;
        enum i40iw_status_code ret = I40IW_ERR_CONFIG;
        struct list_head *pos, *tpos;
        unsigned long flags;

        spin_lock_irqsave(&iwdev->cm_core.listen_list_lock, flags);
        list_for_each_safe(pos, tpos, &cm_parent_listen_node->child_listen_list) {
                child_listen_node = list_entry(pos, struct i40iw_cm_listener, child_listen_list);
                if (child_listen_node->ipv4)
                        i40iw_debug(&iwdev->sc_dev,
                                    I40IW_DEBUG_CM,
                                    "removing child listen for IP=%pI4, port=%d, vlan=%d\n",
                                    child_listen_node->loc_addr,
                                    child_listen_node->loc_port,
                                    child_listen_node->vlan_id);
                else
                        i40iw_debug(&iwdev->sc_dev, I40IW_DEBUG_CM,
                                    "removing child listen for IP=%pI6, port=%d, vlan=%d\n",
                                    child_listen_node->loc_addr,
                                    child_listen_node->loc_port,
                                    child_listen_node->vlan_id);
                list_del(pos);
                memcpy(cm_info->loc_addr, child_listen_node->loc_addr,
                       sizeof(cm_info->loc_addr));
                cm_info->vlan_id = child_listen_node->vlan_id;
                if (child_listen_node->qhash_set) {
                        ret = i40iw_manage_qhash(iwdev, cm_info,
                                                 I40IW_QHASH_TYPE_TCP_SYN,
                                                 I40IW_QHASH_MANAGE_TYPE_DELETE,
                                                 NULL, false);
                        child_listen_node->qhash_set = false;
                } else {
                        ret = I40IW_SUCCESS;
                }
                i40iw_debug(&iwdev->sc_dev,
                            I40IW_DEBUG_CM,
                            "freed pointer = %p\n",
                            child_listen_node);
                kfree(child_listen_node);
                cm_parent_listen_node->cm_core->stats_listen_nodes_destroyed++;
        }
        spin_unlock_irqrestore(&iwdev->cm_core.listen_list_lock, flags);

        return ret;
}

/**
 * i40iw_netdev_vlan_ipv6 - Gets the netdev and vlan
 * @addr: local IPv6 address
 * @vlan_id: vlan id for the given IPv6 address
 *
 * Returns the net_device of the IPv6 address and also sets the
 * vlan id for that address.
 */
static struct net_device *i40iw_netdev_vlan_ipv6(u32 *addr, u16 *vlan_id)
{
        struct net_device *ip_dev = NULL;
        struct in6_addr laddr6;

        if (!IS_ENABLED(CONFIG_IPV6))
                return NULL;
        i40iw_copy_ip_htonl(laddr6.in6_u.u6_addr32, addr);
        if (vlan_id)
                *vlan_id = I40IW_NO_VLAN;
        rcu_read_lock();
        for_each_netdev_rcu(&init_net, ip_dev) {
                if (ipv6_chk_addr(&init_net, &laddr6, ip_dev, 1)) {
                        if (vlan_id)
                                *vlan_id = rdma_vlan_dev_vlan_id(ip_dev);
                        break;
                }
        }
        rcu_read_unlock();
        return ip_dev;
}

/**
 * i40iw_get_vlan_ipv4 - Returns the vlan_id for IPv4 address
 * @addr: local IPv4 address
 */
static u16 i40iw_get_vlan_ipv4(u32 *addr)
{
        struct net_device *netdev;
        u16 vlan_id = I40IW_NO_VLAN;

        netdev = ip_dev_find(&init_net, htonl(addr[0]));
        if (netdev) {
                vlan_id = rdma_vlan_dev_vlan_id(netdev);
                dev_put(netdev);
        }
        return vlan_id;
}

/**
 * i40iw_add_mqh_6 - Adds multiple qhashes for IPv6
 * @iwdev: iWarp device
 * @cm_info: CM info for parent listen node
 * @cm_parent_listen_node: The parent listen node
 *
 * Adds a qhash and a child listen node for every IPv6 address
 * on the adapter and adds the associated qhash filter
 */
static enum i40iw_status_code i40iw_add_mqh_6(struct i40iw_device *iwdev,
                                              struct i40iw_cm_info *cm_info,
                                              struct i40iw_cm_listener *cm_parent_listen_node)
{
        struct net_device *ip_dev;
        struct inet6_dev *idev;
        struct inet6_ifaddr *ifp, *tmp;
        enum i40iw_status_code ret = 0;
        struct i40iw_cm_listener *child_listen_node;
        unsigned long flags;

        rtnl_lock();
        for_each_netdev_rcu(&init_net, ip_dev) {
                if ((((rdma_vlan_dev_vlan_id(ip_dev) < I40IW_NO_VLAN) &&
                      (rdma_vlan_dev_real_dev(ip_dev) == iwdev->netdev)) ||
                     (ip_dev == iwdev->netdev)) && (ip_dev->flags & IFF_UP)) {
                        idev = __in6_dev_get(ip_dev);
                        if (!idev) {
                                i40iw_pr_err("idev == NULL\n");
                                break;
                        }
                        list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
                                i40iw_debug(&iwdev->sc_dev,
                                            I40IW_DEBUG_CM,
                                            "IP=%pI6, vlan_id=%d, MAC=%pM\n",
                                            &ifp->addr,
                                            rdma_vlan_dev_vlan_id(ip_dev),
                                            ip_dev->dev_addr);
                                child_listen_node =
                                        kzalloc(sizeof(*child_listen_node), GFP_ATOMIC);
                                i40iw_debug(&iwdev->sc_dev,
                                            I40IW_DEBUG_CM,
                                            "Allocating child listener %p\n",
                                            child_listen_node);
                                if (!child_listen_node) {
                                        ret = I40IW_ERR_NO_MEMORY;
                                        goto exit;
                                }
                                cm_info->vlan_id = rdma_vlan_dev_vlan_id(ip_dev);
                                cm_parent_listen_node->vlan_id = cm_info->vlan_id;

                                memcpy(child_listen_node, cm_parent_listen_node,
                                       sizeof(*child_listen_node));

                                i40iw_copy_ip_ntohl(child_listen_node->loc_addr,
                                                    ifp->addr.in6_u.u6_addr32);
                                memcpy(cm_info->loc_addr, child_listen_node->loc_addr,
                                       sizeof(cm_info->loc_addr));

                                ret = i40iw_manage_qhash(iwdev, cm_info,
                                                         I40IW_QHASH_TYPE_TCP_SYN,
                                                         I40IW_QHASH_MANAGE_TYPE_ADD,
                                                         NULL, true);
                                if (!ret) {
                                        child_listen_node->qhash_set = true;
                                        spin_lock_irqsave(&iwdev->cm_core.listen_list_lock, flags);
                                        list_add(&child_listen_node->child_listen_list,
                                                 &cm_parent_listen_node->child_listen_list);
                                        spin_unlock_irqrestore(&iwdev->cm_core.listen_list_lock, flags);
                                        cm_parent_listen_node->cm_core->stats_listen_nodes_created++;
                                } else {
                                        kfree(child_listen_node);
                                }
                        }
                }
        }
exit:
        rtnl_unlock();
        return ret;
}

/**
 * i40iw_add_mqh_4 - Adds multiple qhashes for IPv4
 * @iwdev: iWarp device
 * @cm_info: CM info for parent listen node
 * @cm_parent_listen_node: The parent listen node
 *
 * Adds a qhash and a child listen node for every IPv4 address
 * on the adapter and adds the associated qhash filter
 */
static enum i40iw_status_code i40iw_add_mqh_4(
                                struct i40iw_device *iwdev,
                                struct i40iw_cm_info *cm_info,
                                struct i40iw_cm_listener *cm_parent_listen_node)
{
        struct net_device *dev;
        struct in_device *idev;
        struct i40iw_cm_listener *child_listen_node;
        enum i40iw_status_code ret = 0;
        unsigned long flags;

        rtnl_lock();
        for_each_netdev(&init_net, dev) {
                if ((((rdma_vlan_dev_vlan_id(dev) < I40IW_NO_VLAN) &&
                      (rdma_vlan_dev_real_dev(dev) == iwdev->netdev)) ||
                    (dev == iwdev->netdev)) && (dev->flags & IFF_UP)) {
                        idev = in_dev_get(dev);
                        for_ifa(idev) {
                                i40iw_debug(&iwdev->sc_dev,
                                            I40IW_DEBUG_CM,
                                            "Allocating child CM Listener forIP=%pI4, vlan_id=%d, MAC=%pM\n",
                                            &ifa->ifa_address,
                                            rdma_vlan_dev_vlan_id(dev),
                                            dev->dev_addr);
                                child_listen_node = kzalloc(sizeof(*child_listen_node), GFP_KERNEL);
                                cm_parent_listen_node->cm_core->stats_listen_nodes_created++;
                                i40iw_debug(&iwdev->sc_dev,
                                            I40IW_DEBUG_CM,
                                            "Allocating child listener %p\n",
                                            child_listen_node);
                                if (!child_listen_node) {
                                        in_dev_put(idev);
                                        ret = I40IW_ERR_NO_MEMORY;
                                        goto exit;
                                }
                                cm_info->vlan_id = rdma_vlan_dev_vlan_id(dev);
                                cm_parent_listen_node->vlan_id = cm_info->vlan_id;
                                memcpy(child_listen_node,
                                       cm_parent_listen_node,
                                       sizeof(*child_listen_node));

                                child_listen_node->loc_addr[0] = ntohl(ifa->ifa_address);
                                memcpy(cm_info->loc_addr, child_listen_node->loc_addr,
                                       sizeof(cm_info->loc_addr));

                                ret = i40iw_manage_qhash(iwdev,
                                                         cm_info,
                                                         I40IW_QHASH_TYPE_TCP_SYN,
                                                         I40IW_QHASH_MANAGE_TYPE_ADD,
                                                         NULL,
                                                         true);
                                if (!ret) {
                                        child_listen_node->qhash_set = true;
                                        spin_lock_irqsave(&iwdev->cm_core.listen_list_lock, flags);
                                        list_add(&child_listen_node->child_listen_list,
                                                 &cm_parent_listen_node->child_listen_list);
                                        spin_unlock_irqrestore(&iwdev->cm_core.listen_list_lock, flags);
                                } else {
                                        kfree(child_listen_node);
                                        cm_parent_listen_node->cm_core->stats_listen_nodes_created--;
                                }
                        }
                        endfor_ifa(idev);
                        in_dev_put(idev);
                }
        }
exit:
        rtnl_unlock();
        return ret;
}

/**
 * i40iw_dec_refcnt_listen - delete listener and associated cm nodes
 * @cm_core: cm's core
 * @free_hanging_nodes: to free associated cm_nodes
 * @apbvt_del: flag to delete the apbvt
 */
static int i40iw_dec_refcnt_listen(struct i40iw_cm_core *cm_core,
                                   struct i40iw_cm_listener *listener,
                                   int free_hanging_nodes, bool apbvt_del)
{
        int ret = -EINVAL;
        int err = 0;
        struct list_head *list_pos;
        struct list_head *list_temp;
        struct i40iw_cm_node *cm_node;
        struct list_head reset_list;
        struct i40iw_cm_info nfo;
        struct i40iw_cm_node *loopback;
        enum i40iw_cm_node_state old_state;
        unsigned long flags;

        /* free non-accelerated child nodes for this listener */
        INIT_LIST_HEAD(&reset_list);
        if (free_hanging_nodes) {
                spin_lock_irqsave(&cm_core->ht_lock, flags);
                list_for_each_safe(list_pos,
                                   list_temp, &cm_core->non_accelerated_list) {
                        cm_node = container_of(list_pos, struct i40iw_cm_node, list);
                        if ((cm_node->listener == listener) &&
                            !cm_node->accelerated) {
                                atomic_inc(&cm_node->ref_count);
                                list_add(&cm_node->reset_entry, &reset_list);
                        }
                }
                spin_unlock_irqrestore(&cm_core->ht_lock, flags);
        }

        list_for_each_safe(list_pos, list_temp, &reset_list) {
                cm_node = container_of(list_pos, struct i40iw_cm_node, reset_entry);
                loopback = cm_node->loopbackpartner;
                if (cm_node->state >= I40IW_CM_STATE_FIN_WAIT1) {
                        i40iw_rem_ref_cm_node(cm_node);
                } else {
                        if (!loopback) {
                                i40iw_cleanup_retrans_entry(cm_node);
                                err = i40iw_send_reset(cm_node);
                                if (err) {
                                        cm_node->state = I40IW_CM_STATE_CLOSED;
                                        i40iw_pr_err("send reset\n");
                                } else {
                                        old_state = cm_node->state;
                                        cm_node->state = I40IW_CM_STATE_LISTENER_DESTROYED;
                                        if (old_state != I40IW_CM_STATE_MPAREQ_RCVD)
                                                i40iw_rem_ref_cm_node(cm_node);
                                }
                        } else {
                                struct i40iw_cm_event event;

                                event.cm_node = loopback;
                                memcpy(event.cm_info.rem_addr,
                                       loopback->rem_addr, sizeof(event.cm_info.rem_addr));
                                memcpy(event.cm_info.loc_addr,
                                       loopback->loc_addr, sizeof(event.cm_info.loc_addr));
                                event.cm_info.rem_port = loopback->rem_port;
                                event.cm_info.loc_port = loopback->loc_port;
                                event.cm_info.cm_id = loopback->cm_id;
                                event.cm_info.ipv4 = loopback->ipv4;
                                atomic_inc(&loopback->ref_count);
                                loopback->state = I40IW_CM_STATE_CLOSED;
                                i40iw_event_connect_error(&event);
                                cm_node->state = I40IW_CM_STATE_LISTENER_DESTROYED;
                                i40iw_rem_ref_cm_node(cm_node);
                        }
                }
        }

        if (!atomic_dec_return(&listener->ref_count)) {
                spin_lock_irqsave(&cm_core->listen_list_lock, flags);
                list_del(&listener->list);
                spin_unlock_irqrestore(&cm_core->listen_list_lock, flags);

                if (listener->iwdev) {
                        if (apbvt_del)
                                i40iw_manage_apbvt(listener->iwdev,
                                                   listener->loc_port,
                                                   I40IW_MANAGE_APBVT_DEL);

                        memcpy(nfo.loc_addr, listener->loc_addr, sizeof(nfo.loc_addr));
                        nfo.loc_port = listener->loc_port;
                        nfo.ipv4 = listener->ipv4;
                        nfo.vlan_id = listener->vlan_id;
                        nfo.user_pri = listener->user_pri;

                        if (!list_empty(&listener->child_listen_list)) {
                                i40iw_del_multiple_qhash(listener->iwdev, &nfo, listener);
                        } else {
                                if (listener->qhash_set)
                                        i40iw_manage_qhash(listener->iwdev,
                                                           &nfo,
                                                           I40IW_QHASH_TYPE_TCP_SYN,
                                                           I40IW_QHASH_MANAGE_TYPE_DELETE,
                                                           NULL,
                                                           false);
                        }
                }

                cm_core->stats_listen_destroyed++;
                kfree(listener);
                cm_core->stats_listen_nodes_destroyed++;
                listener = NULL;
                ret = 0;
        }

        if (listener) {
                if (atomic_read(&listener->pend_accepts_cnt) > 0)
                        i40iw_debug(cm_core->dev,
                                    I40IW_DEBUG_CM,
                                    "%s: listener (%p) pending accepts=%u\n",
                                    __func__,
                                    listener,
                                    atomic_read(&listener->pend_accepts_cnt));
        }

        return ret;
}

/**
 * i40iw_cm_del_listen - delete a linstener
 * @cm_core: cm's core
  * @listener: passive connection's listener
 * @apbvt_del: flag to delete apbvt
 */
static int i40iw_cm_del_listen(struct i40iw_cm_core *cm_core,
                               struct i40iw_cm_listener *listener,
                               bool apbvt_del)
{
        listener->listener_state = I40IW_CM_LISTENER_PASSIVE_STATE;
        listener->cm_id = NULL; /* going to be destroyed pretty soon */
        return i40iw_dec_refcnt_listen(cm_core, listener, 1, apbvt_del);
}

/**
 * i40iw_addr_resolve_neigh - resolve neighbor address
 * @iwdev: iwarp device structure
 * @src_ip: local ip address
 * @dst_ip: remote ip address
 * @arpindex: if there is an arp entry
 */
static int i40iw_addr_resolve_neigh(struct i40iw_device *iwdev,
                                    u32 src_ip,
                                    u32 dst_ip,
                                    int arpindex)
{
        struct rtable *rt;
        struct neighbour *neigh;
        int rc = arpindex;
        struct net_device *netdev = iwdev->netdev;
        __be32 dst_ipaddr = htonl(dst_ip);
        __be32 src_ipaddr = htonl(src_ip);

        rt = ip_route_output(&init_net, dst_ipaddr, src_ipaddr, 0, 0);
        if (IS_ERR(rt)) {
                i40iw_pr_err("ip_route_output\n");
                return rc;
        }

        if (netif_is_bond_slave(netdev))
                netdev = netdev_master_upper_dev_get(netdev);

        neigh = dst_neigh_lookup(&rt->dst, &dst_ipaddr);

        rcu_read_lock();
        if (neigh) {
                if (neigh->nud_state & NUD_VALID) {
                        if (arpindex >= 0) {
                                if (ether_addr_equal(iwdev->arp_table[arpindex].mac_addr,
                                                     neigh->ha))
                                        /* Mac address same as arp table */
                                        goto resolve_neigh_exit;
                                i40iw_manage_arp_cache(iwdev,
                                                       iwdev->arp_table[arpindex].mac_addr,
                                                       &dst_ip,
                                                       true,
                                                       I40IW_ARP_DELETE);
                        }

                        i40iw_manage_arp_cache(iwdev, neigh->ha, &dst_ip, true, I40IW_ARP_ADD);
                        rc = i40iw_arp_table(iwdev, &dst_ip, true, NULL, I40IW_ARP_RESOLVE);
                } else {
                        neigh_event_send(neigh, NULL);
                }
        }
 resolve_neigh_exit:

        rcu_read_unlock();
        if (neigh)
                neigh_release(neigh);

        ip_rt_put(rt);
        return rc;
}

/**
 * i40iw_get_dst_ipv6
 */
static struct dst_entry *i40iw_get_dst_ipv6(struct sockaddr_in6 *src_addr,
                                            struct sockaddr_in6 *dst_addr)
{
        struct dst_entry *dst;
        struct flowi6 fl6;

        memset(&fl6, 0, sizeof(fl6));
        fl6.daddr = dst_addr->sin6_addr;
        fl6.saddr = src_addr->sin6_addr;
        if (ipv6_addr_type(&fl6.daddr) & IPV6_ADDR_LINKLOCAL)
                fl6.flowi6_oif = dst_addr->sin6_scope_id;

        dst = ip6_route_output(&init_net, NULL, &fl6);
        return dst;
}

/**
 * i40iw_addr_resolve_neigh_ipv6 - resolve neighbor ipv6 address
 * @iwdev: iwarp device structure
 * @dst_ip: remote ip address
 * @arpindex: if there is an arp entry
 */
static int i40iw_addr_resolve_neigh_ipv6(struct i40iw_device *iwdev,
                                         u32 *src,
                                         u32 *dest,
                                         int arpindex)
{
        struct neighbour *neigh;
        int rc = arpindex;
        struct net_device *netdev = iwdev->netdev;
        struct dst_entry *dst;
        struct sockaddr_in6 dst_addr;
        struct sockaddr_in6 src_addr;

        memset(&dst_addr, 0, sizeof(dst_addr));
        dst_addr.sin6_family = AF_INET6;
        i40iw_copy_ip_htonl(dst_addr.sin6_addr.in6_u.u6_addr32, dest);
        memset(&src_addr, 0, sizeof(src_addr));
        src_addr.sin6_family = AF_INET6;
        i40iw_copy_ip_htonl(src_addr.sin6_addr.in6_u.u6_addr32, src);
        dst = i40iw_get_dst_ipv6(&src_addr, &dst_addr);
        if (!dst || dst->error) {
                if (dst) {
                        dst_release(dst);
                        i40iw_pr_err("ip6_route_output returned dst->error = %d\n",
                                     dst->error);
                }
                return rc;
        }

        if (netif_is_bond_slave(netdev))
                netdev = netdev_master_upper_dev_get(netdev);

        neigh = dst_neigh_lookup(dst, dst_addr.sin6_addr.in6_u.u6_addr32);

        rcu_read_lock();
        if (neigh) {
                i40iw_debug(&iwdev->sc_dev, I40IW_DEBUG_CM, "dst_neigh_lookup MAC=%pM\n", neigh->ha);
                if (neigh->nud_state & NUD_VALID) {
                        if (arpindex >= 0) {
                                if (ether_addr_equal
                                    (iwdev->arp_table[arpindex].mac_addr,
                                     neigh->ha)) {
                                        /* Mac address same as in arp table */
                                        goto resolve_neigh_exit6;
                                }
                                i40iw_manage_arp_cache(iwdev,
                                                       iwdev->arp_table[arpindex].mac_addr,
                                                       dest,
                                                       false,
                                                       I40IW_ARP_DELETE);
                        }
                        i40iw_manage_arp_cache(iwdev,
                                               neigh->ha,
                                               dest,
                                               false,
                                               I40IW_ARP_ADD);
                        rc = i40iw_arp_table(iwdev,
                                             dest,
                                             false,
                                             NULL,
                                             I40IW_ARP_RESOLVE);
                } else {
                        neigh_event_send(neigh, NULL);
                }
        }

 resolve_neigh_exit6:
        rcu_read_unlock();
        if (neigh)
                neigh_release(neigh);
        dst_release(dst);
        return rc;
}

/**
 * i40iw_ipv4_is_loopback - check if loopback
 * @loc_addr: local addr to compare
 * @rem_addr: remote address
 */
static bool i40iw_ipv4_is_loopback(u32 loc_addr, u32 rem_addr)
{
        return ipv4_is_loopback(htonl(rem_addr)) || (loc_addr == rem_addr);
}

/**
 * i40iw_ipv6_is_loopback - check if loopback
 * @loc_addr: local addr to compare
 * @rem_addr: remote address
 */
static bool i40iw_ipv6_is_loopback(u32 *loc_addr, u32 *rem_addr)
{
        struct in6_addr raddr6;

        i40iw_copy_ip_htonl(raddr6.in6_u.u6_addr32, rem_addr);
        return !memcmp(loc_addr, rem_addr, 16) || ipv6_addr_loopback(&raddr6);
}

/**
 * i40iw_make_cm_node - create a new instance of a cm node
 * @cm_core: cm's core
 * @iwdev: iwarp device structure
 * @cm_info: quad info for connection
 * @listener: passive connection's listener
 */
static struct i40iw_cm_node *i40iw_make_cm_node(
                                   struct i40iw_cm_core *cm_core,
                                   struct i40iw_device *iwdev,
                                   struct i40iw_cm_info *cm_info,
                                   struct i40iw_cm_listener *listener)
{
        struct i40iw_cm_node *cm_node;
        int oldarpindex;
        int arpindex;
        struct net_device *netdev = iwdev->netdev;

        /* create an hte and cm_node for this instance */
        cm_node = kzalloc(sizeof(*cm_node), GFP_ATOMIC);
        if (!cm_node)
                return NULL;

        /* set our node specific transport info */
        cm_node->ipv4 = cm_info->ipv4;
        cm_node->vlan_id = cm_info->vlan_id;
        if ((cm_node->vlan_id == I40IW_NO_VLAN) && iwdev->dcb)
                cm_node->vlan_id = 0;
        cm_node->tos = cm_info->tos;
        cm_node->user_pri = cm_info->user_pri;
        if (listener) {
                if (listener->tos != cm_info->tos)
                        i40iw_debug(&iwdev->sc_dev, I40IW_DEBUG_DCB,
                                    "application TOS[%d] and remote client TOS[%d] mismatch\n",
                                     listener->tos, cm_info->tos);
                cm_node->tos = max(listener->tos, cm_info->tos);
                cm_node->user_pri = rt_tos2priority(cm_node->tos);
                i40iw_debug(&iwdev->sc_dev, I40IW_DEBUG_DCB, "listener: TOS:[%d] UP:[%d]\n",
                            cm_node->tos, cm_node->user_pri);
        }
        memcpy(cm_node->loc_addr, cm_info->loc_addr, sizeof(cm_node->loc_addr));
        memcpy(cm_node->rem_addr, cm_info->rem_addr, sizeof(cm_node->rem_addr));
        cm_node->loc_port = cm_info->loc_port;
        cm_node->rem_port = cm_info->rem_port;

        cm_node->mpa_frame_rev = iwdev->mpa_version;
        cm_node->send_rdma0_op = SEND_RDMA_READ_ZERO;
        cm_node->ird_size = I40IW_MAX_IRD_SIZE;
        cm_node->ord_size = I40IW_MAX_ORD_SIZE;

        cm_node->listener = listener;
        cm_node->cm_id = cm_info->cm_id;
        ether_addr_copy(cm_node->loc_mac, netdev->dev_addr);
        spin_lock_init(&cm_node->retrans_list_lock);
        cm_node->ack_rcvd = false;

        atomic_set(&cm_node->ref_count, 1);
        /* associate our parent CM core */
        cm_node->cm_core = cm_core;
        cm_node->tcp_cntxt.loc_id = I40IW_CM_DEF_LOCAL_ID;
        cm_node->tcp_cntxt.rcv_wscale = I40IW_CM_DEFAULT_RCV_WND_SCALE;
        cm_node->tcp_cntxt.rcv_wnd =
                        I40IW_CM_DEFAULT_RCV_WND_SCALED >> I40IW_CM_DEFAULT_RCV_WND_SCALE;
        if (cm_node->ipv4) {
                cm_node->tcp_cntxt.loc_seq_num = secure_tcp_seq(htonl(cm_node->loc_addr[0]),
                                                        htonl(cm_node->rem_addr[0]),
                                                        htons(cm_node->loc_port),
                                                        htons(cm_node->rem_port));
                cm_node->tcp_cntxt.mss = iwdev->vsi.mtu - I40IW_MTU_TO_MSS_IPV4;
        } else if (IS_ENABLED(CONFIG_IPV6)) {
                __be32 loc[4] = {
                        htonl(cm_node->loc_addr[0]), htonl(cm_node->loc_addr[1]),
                        htonl(cm_node->loc_addr[2]), htonl(cm_node->loc_addr[3])
                };
                __be32 rem[4] = {
                        htonl(cm_node->rem_addr[0]), htonl(cm_node->rem_addr[1]),
                        htonl(cm_node->rem_addr[2]), htonl(cm_node->rem_addr[3])
                };
                cm_node->tcp_cntxt.loc_seq_num = secure_tcpv6_seq(loc, rem,
                                                        htons(cm_node->loc_port),
                                                        htons(cm_node->rem_port));
                cm_node->tcp_cntxt.mss = iwdev->vsi.mtu - I40IW_MTU_TO_MSS_IPV6;
        }

        cm_node->iwdev = iwdev;
        cm_node->dev = &iwdev->sc_dev;

        if ((cm_node->ipv4 &&
             i40iw_ipv4_is_loopback(cm_node->loc_addr[0], cm_node->rem_addr[0])) ||
             (!cm_node->ipv4 && i40iw_ipv6_is_loopback(cm_node->loc_addr,
                                                       cm_node->rem_addr))) {
                arpindex = i40iw_arp_table(iwdev,
                                           cm_node->rem_addr,
                                           false,
                                           NULL,
                                           I40IW_ARP_RESOLVE);
        } else {
                oldarpindex = i40iw_arp_table(iwdev,
                                              cm_node->rem_addr,
                                              false,
                                              NULL,
                                              I40IW_ARP_RESOLVE);
                if (cm_node->ipv4)
                        arpindex = i40iw_addr_resolve_neigh(iwdev,
                                                            cm_info->loc_addr[0],
                                                            cm_info->rem_addr[0],
                                                            oldarpindex);
                else if (IS_ENABLED(CONFIG_IPV6))
                        arpindex = i40iw_addr_resolve_neigh_ipv6(iwdev,
                                                                 cm_info->loc_addr,
                                                                 cm_info->rem_addr,
                                                                 oldarpindex);
                else
                        arpindex = -EINVAL;
        }
        if (arpindex < 0) {
                i40iw_pr_err("cm_node arpindex\n");
                kfree(cm_node);
                return NULL;
        }
        ether_addr_copy(cm_node->rem_mac, iwdev->arp_table[arpindex].mac_addr);
        i40iw_add_hte_node(cm_core, cm_node);
        cm_core->stats_nodes_created++;
        return cm_node;
}

/**
 * i40iw_rem_ref_cm_node - destroy an instance of a cm node
 * @cm_node: connection's node
 */
static void i40iw_rem_ref_cm_node(struct i40iw_cm_node *cm_node)
{
        struct i40iw_cm_core *cm_core = cm_node->cm_core;
        struct i40iw_qp *iwqp;
        struct i40iw_cm_info nfo;
        unsigned long flags;

        spin_lock_irqsave(&cm_node->cm_core->ht_lock, flags);
        if (atomic_dec_return(&cm_node->ref_count)) {
                spin_unlock_irqrestore(&cm_node->cm_core->ht_lock, flags);
                return;
        }
        list_del(&cm_node->list);
        spin_unlock_irqrestore(&cm_node->cm_core->ht_lock, flags);

        /* if the node is destroyed before connection was accelerated */
        if (!cm_node->accelerated && cm_node->accept_pend) {
                pr_err("node destroyed before established\n");
                atomic_dec(&cm_node->listener->pend_accepts_cnt);
        }
        if (cm_node->close_entry)
                i40iw_handle_close_entry(cm_node, 0);
        if (cm_node->listener) {
                i40iw_dec_refcnt_listen(cm_core, cm_node->listener, 0, true);
        } else {
                if (cm_node->apbvt_set) {
                        i40iw_manage_apbvt(cm_node->iwdev,
                                           cm_node->loc_port,
                                           I40IW_MANAGE_APBVT_DEL);
                        cm_node->apbvt_set = 0;
                }
                i40iw_get_addr_info(cm_node, &nfo);
                if (cm_node->qhash_set) {
                        i40iw_manage_qhash(cm_node->iwdev,
                                           &nfo,
                                           I40IW_QHASH_TYPE_TCP_ESTABLISHED,
                                           I40IW_QHASH_MANAGE_TYPE_DELETE,
                                           NULL,
                                           false);
                        cm_node->qhash_set = 0;
                }
        }

        iwqp = cm_node->iwqp;
        if (iwqp) {
                iwqp->cm_node = NULL;
                i40iw_rem_ref(&iwqp->ibqp);
                cm_node->iwqp = NULL;
        } else if (cm_node->qhash_set) {
                i40iw_get_addr_info(cm_node, &nfo);
                i40iw_manage_qhash(cm_node->iwdev,
                                   &nfo,
                                   I40IW_QHASH_TYPE_TCP_ESTABLISHED,
                                   I40IW_QHASH_MANAGE_TYPE_DELETE,
                                   NULL,
                                   false);
                cm_node->qhash_set = 0;
        }

        cm_node->cm_core->stats_nodes_destroyed++;
        kfree(cm_node);
}

/**
 * i40iw_handle_fin_pkt - FIN packet received
 * @cm_node: connection's node
 */
static void i40iw_handle_fin_pkt(struct i40iw_cm_node *cm_node)
{
        u32 ret;

        switch (cm_node->state) {
        case I40IW_CM_STATE_SYN_RCVD:
        case I40IW_CM_STATE_SYN_SENT:
        case I40IW_CM_STATE_ESTABLISHED:
        case I40IW_CM_STATE_MPAREJ_RCVD:
                cm_node->tcp_cntxt.rcv_nxt++;
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_LAST_ACK;
                i40iw_send_fin(cm_node);
                break;
        case I40IW_CM_STATE_MPAREQ_SENT:
                i40iw_create_event(cm_node, I40IW_CM_EVENT_ABORTED);
                cm_node->tcp_cntxt.rcv_nxt++;
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_CLOSED;
                atomic_inc(&cm_node->ref_count);
                i40iw_send_reset(cm_node);
                break;
        case I40IW_CM_STATE_FIN_WAIT1:
                cm_node->tcp_cntxt.rcv_nxt++;
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_CLOSING;
                i40iw_send_ack(cm_node);
                /*
                 * Wait for ACK as this is simultaneous close.
                 * After we receive ACK, do not send anything.
                 * Just rm the node.
                 */
                break;
        case I40IW_CM_STATE_FIN_WAIT2:
                cm_node->tcp_cntxt.rcv_nxt++;
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_TIME_WAIT;
                i40iw_send_ack(cm_node);
                ret =
                    i40iw_schedule_cm_timer(cm_node, NULL, I40IW_TIMER_TYPE_CLOSE, 1, 0);
                if (ret)
                        i40iw_pr_err("node %p state = %d\n", cm_node, cm_node->state);
                break;
        case I40IW_CM_STATE_TIME_WAIT:
                cm_node->tcp_cntxt.rcv_nxt++;
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_CLOSED;
                i40iw_rem_ref_cm_node(cm_node);
                break;
        case I40IW_CM_STATE_OFFLOADED:
        default:
                i40iw_pr_err("bad state node %p state = %d\n", cm_node, cm_node->state);
                break;
        }
}

/**
 * i40iw_handle_rst_pkt - process received RST packet
 * @cm_node: connection's node
 * @rbuf: receive buffer
 */
static void i40iw_handle_rst_pkt(struct i40iw_cm_node *cm_node,
                                 struct i40iw_puda_buf *rbuf)
{
        i40iw_cleanup_retrans_entry(cm_node);
        switch (cm_node->state) {
        case I40IW_CM_STATE_SYN_SENT:
        case I40IW_CM_STATE_MPAREQ_SENT:
                switch (cm_node->mpa_frame_rev) {
                case IETF_MPA_V2:
                        cm_node->mpa_frame_rev = IETF_MPA_V1;
                        /* send a syn and goto syn sent state */
                        cm_node->state = I40IW_CM_STATE_SYN_SENT;
                        if (i40iw_send_syn(cm_node, 0))
                                i40iw_active_open_err(cm_node, false);
                        break;
                case IETF_MPA_V1:
                default:
                        i40iw_active_open_err(cm_node, false);
                        break;
                }
                break;
        case I40IW_CM_STATE_MPAREQ_RCVD:
                atomic_add_return(1, &cm_node->passive_state);
                break;
        case I40IW_CM_STATE_ESTABLISHED:
        case I40IW_CM_STATE_SYN_RCVD:
        case I40IW_CM_STATE_LISTENING:
                i40iw_pr_err("Bad state state = %d\n", cm_node->state);
                i40iw_passive_open_err(cm_node, false);
                break;
        case I40IW_CM_STATE_OFFLOADED:
                i40iw_active_open_err(cm_node, false);
                break;
        case I40IW_CM_STATE_CLOSED:
                break;
        case I40IW_CM_STATE_FIN_WAIT2:
        case I40IW_CM_STATE_FIN_WAIT1:
        case I40IW_CM_STATE_LAST_ACK:
                cm_node->cm_id->rem_ref(cm_node->cm_id);
                /* fall through */
        case I40IW_CM_STATE_TIME_WAIT:
                cm_node->state = I40IW_CM_STATE_CLOSED;
                i40iw_rem_ref_cm_node(cm_node);
                break;
        default:
                break;
        }
}

/**
 * i40iw_handle_rcv_mpa - Process a recv'd mpa buffer
 * @cm_node: connection's node
 * @rbuf: receive buffer
 */
static void i40iw_handle_rcv_mpa(struct i40iw_cm_node *cm_node,
                                 struct i40iw_puda_buf *rbuf)
{
        int ret;
        int datasize = rbuf->datalen;
        u8 *dataloc = rbuf->data;

        enum i40iw_cm_event_type type = I40IW_CM_EVENT_UNKNOWN;
        u32 res_type;

        ret = i40iw_parse_mpa(cm_node, dataloc, &res_type, datasize);
        if (ret) {
                if (cm_node->state == I40IW_CM_STATE_MPAREQ_SENT)
                        i40iw_active_open_err(cm_node, true);
                else
                        i40iw_passive_open_err(cm_node, true);
                return;
        }

        switch (cm_node->state) {
        case I40IW_CM_STATE_ESTABLISHED:
                if (res_type == I40IW_MPA_REQUEST_REJECT)
                        i40iw_pr_err("state for reject\n");
                cm_node->state = I40IW_CM_STATE_MPAREQ_RCVD;
                type = I40IW_CM_EVENT_MPA_REQ;
                i40iw_send_ack(cm_node);        /* ACK received MPA request */
                atomic_set(&cm_node->passive_state,
                           I40IW_PASSIVE_STATE_INDICATED);
                break;
        case I40IW_CM_STATE_MPAREQ_SENT:
                i40iw_cleanup_retrans_entry(cm_node);
                if (res_type == I40IW_MPA_REQUEST_REJECT) {
                        type = I40IW_CM_EVENT_MPA_REJECT;
                        cm_node->state = I40IW_CM_STATE_MPAREJ_RCVD;
                } else {
                        type = I40IW_CM_EVENT_CONNECTED;
                        cm_node->state = I40IW_CM_STATE_OFFLOADED;
                }
                i40iw_send_ack(cm_node);
                break;
        default:
                pr_err("%s wrong cm_node state =%d\n", __func__, cm_node->state);
                break;
        }
        i40iw_create_event(cm_node, type);
}

/**
 * i40iw_indicate_pkt_err - Send up err event to cm
 * @cm_node: connection's node
 */
static void i40iw_indicate_pkt_err(struct i40iw_cm_node *cm_node)
{
        switch (cm_node->state) {
        case I40IW_CM_STATE_SYN_SENT:
        case I40IW_CM_STATE_MPAREQ_SENT:
                i40iw_active_open_err(cm_node, true);
                break;
        case I40IW_CM_STATE_ESTABLISHED:
        case I40IW_CM_STATE_SYN_RCVD:
                i40iw_passive_open_err(cm_node, true);
                break;
        case I40IW_CM_STATE_OFFLOADED:
        default:
                break;
        }
}

/**
 * i40iw_check_syn - Check for error on received syn ack
 * @cm_node: connection's node
 * @tcph: pointer tcp header
 */
static int i40iw_check_syn(struct i40iw_cm_node *cm_node, struct tcphdr *tcph)
{
        int err = 0;

        if (ntohl(tcph->ack_seq) != cm_node->tcp_cntxt.loc_seq_num) {
                err = 1;
                i40iw_active_open_err(cm_node, true);
        }
        return err;
}

/**
 * i40iw_check_seq - check seq numbers if OK
 * @cm_node: connection's node
 * @tcph: pointer tcp header
 */
static int i40iw_check_seq(struct i40iw_cm_node *cm_node, struct tcphdr *tcph)
{
        int err = 0;
        u32 seq;
        u32 ack_seq;
        u32 loc_seq_num = cm_node->tcp_cntxt.loc_seq_num;
        u32 rcv_nxt = cm_node->tcp_cntxt.rcv_nxt;
        u32 rcv_wnd;

        seq = ntohl(tcph->seq);
        ack_seq = ntohl(tcph->ack_seq);
        rcv_wnd = cm_node->tcp_cntxt.rcv_wnd;
        if (ack_seq != loc_seq_num)
                err = -1;
        else if (!between(seq, rcv_nxt, (rcv_nxt + rcv_wnd)))
                err = -1;
        if (err) {
                i40iw_pr_err("seq number\n");
                i40iw_indicate_pkt_err(cm_node);
        }
        return err;
}

/**
 * i40iw_handle_syn_pkt - is for Passive node
 * @cm_node: connection's node
 * @rbuf: receive buffer
 */
static void i40iw_handle_syn_pkt(struct i40iw_cm_node *cm_node,
                                 struct i40iw_puda_buf *rbuf)
{
        struct tcphdr *tcph = (struct tcphdr *)rbuf->tcph;
        int ret;
        u32 inc_sequence;
        int optionsize;
        struct i40iw_cm_info nfo;

        optionsize = (tcph->doff << 2) - sizeof(struct tcphdr);
        inc_sequence = ntohl(tcph->seq);

        switch (cm_node->state) {
        case I40IW_CM_STATE_SYN_SENT:
        case I40IW_CM_STATE_MPAREQ_SENT:
                /* Rcvd syn on active open connection */
                i40iw_active_open_err(cm_node, 1);
                break;
        case I40IW_CM_STATE_LISTENING:
                /* Passive OPEN */
                if (atomic_read(&cm_node->listener->pend_accepts_cnt) >
                    cm_node->listener->backlog) {
                        cm_node->cm_core->stats_backlog_drops++;
                        i40iw_passive_open_err(cm_node, false);
                        break;
                }
                ret = i40iw_handle_tcp_options(cm_node, tcph, optionsize, 1);
                if (ret) {
                        i40iw_passive_open_err(cm_node, false);
                        /* drop pkt */
                        break;
                }
                cm_node->tcp_cntxt.rcv_nxt = inc_sequence + 1;
                cm_node->accept_pend = 1;
                atomic_inc(&cm_node->listener->pend_accepts_cnt);

                cm_node->state = I40IW_CM_STATE_SYN_RCVD;
                i40iw_get_addr_info(cm_node, &nfo);
                ret = i40iw_manage_qhash(cm_node->iwdev,
                                         &nfo,
                                         I40IW_QHASH_TYPE_TCP_ESTABLISHED,
                                         I40IW_QHASH_MANAGE_TYPE_ADD,
                                         (void *)cm_node,
                                         false);
                cm_node->qhash_set = true;
                break;
        case I40IW_CM_STATE_CLOSED:
                i40iw_cleanup_retrans_entry(cm_node);
                atomic_inc(&cm_node->ref_count);
                i40iw_send_reset(cm_node);
                break;
        case I40IW_CM_STATE_OFFLOADED:
        case I40IW_CM_STATE_ESTABLISHED:
        case I40IW_CM_STATE_FIN_WAIT1:
        case I40IW_CM_STATE_FIN_WAIT2:
        case I40IW_CM_STATE_MPAREQ_RCVD:
        case I40IW_CM_STATE_LAST_ACK:
        case I40IW_CM_STATE_CLOSING:
        case I40IW_CM_STATE_UNKNOWN:
        default:
                break;
        }
}

/**
 * i40iw_handle_synack_pkt - Process SYN+ACK packet (active side)
 * @cm_node: connection's node
 * @rbuf: receive buffer
 */
static void i40iw_handle_synack_pkt(struct i40iw_cm_node *cm_node,
                                    struct i40iw_puda_buf *rbuf)
{
        struct tcphdr *tcph = (struct tcphdr *)rbuf->tcph;
        int ret;
        u32 inc_sequence;
        int optionsize;

        optionsize = (tcph->doff << 2) - sizeof(struct tcphdr);
        inc_sequence = ntohl(tcph->seq);
        switch (cm_node->state) {
        case I40IW_CM_STATE_SYN_SENT:
                i40iw_cleanup_retrans_entry(cm_node);
                /* active open */
                if (i40iw_check_syn(cm_node, tcph)) {
                        i40iw_pr_err("check syn fail\n");
                        return;
                }
                cm_node->tcp_cntxt.rem_ack_num = ntohl(tcph->ack_seq);
                /* setup options */
                ret = i40iw_handle_tcp_options(cm_node, tcph, optionsize, 0);
                if (ret) {
                        i40iw_debug(cm_node->dev,
                                    I40IW_DEBUG_CM,
                                    "cm_node=%p tcp_options failed\n",
                                    cm_node);
                        break;
                }
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->tcp_cntxt.rcv_nxt = inc_sequence + 1;
                i40iw_send_ack(cm_node);        /* ACK  for the syn_ack */
                ret = i40iw_send_mpa_request(cm_node);
                if (ret) {
                        i40iw_debug(cm_node->dev,
                                    I40IW_DEBUG_CM,
                                    "cm_node=%p i40iw_send_mpa_request failed\n",
                                    cm_node);
                        break;
                }
                cm_node->state = I40IW_CM_STATE_MPAREQ_SENT;
                break;
        case I40IW_CM_STATE_MPAREQ_RCVD:
                i40iw_passive_open_err(cm_node, true);
                break;
        case I40IW_CM_STATE_LISTENING:
                cm_node->tcp_cntxt.loc_seq_num = ntohl(tcph->ack_seq);
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_CLOSED;
                i40iw_send_reset(cm_node);
                break;
        case I40IW_CM_STATE_CLOSED:
                cm_node->tcp_cntxt.loc_seq_num = ntohl(tcph->ack_seq);
                i40iw_cleanup_retrans_entry(cm_node);
                atomic_inc(&cm_node->ref_count);
                i40iw_send_reset(cm_node);
                break;
        case I40IW_CM_STATE_ESTABLISHED:
        case I40IW_CM_STATE_FIN_WAIT1:
        case I40IW_CM_STATE_FIN_WAIT2:
        case I40IW_CM_STATE_LAST_ACK:
        case I40IW_CM_STATE_OFFLOADED:
        case I40IW_CM_STATE_CLOSING:
        case I40IW_CM_STATE_UNKNOWN:
        case I40IW_CM_STATE_MPAREQ_SENT:
        default:
                break;
        }
}

/**
 * i40iw_handle_ack_pkt - process packet with ACK
 * @cm_node: connection's node
 * @rbuf: receive buffer
 */
static int i40iw_handle_ack_pkt(struct i40iw_cm_node *cm_node,
                                struct i40iw_puda_buf *rbuf)
{
        struct tcphdr *tcph = (struct tcphdr *)rbuf->tcph;
        u32 inc_sequence;
        int ret = 0;
        int optionsize;
        u32 datasize = rbuf->datalen;

        optionsize = (tcph->doff << 2) - sizeof(struct tcphdr);

        if (i40iw_check_seq(cm_node, tcph))
                return -EINVAL;

        inc_sequence = ntohl(tcph->seq);
        switch (cm_node->state) {
        case I40IW_CM_STATE_SYN_RCVD:
                i40iw_cleanup_retrans_entry(cm_node);
                ret = i40iw_handle_tcp_options(cm_node, tcph, optionsize, 1);
                if (ret)
                        break;
                cm_node->tcp_cntxt.rem_ack_num = ntohl(tcph->ack_seq);
                cm_node->state = I40IW_CM_STATE_ESTABLISHED;
                if (datasize) {
                        cm_node->tcp_cntxt.rcv_nxt = inc_sequence + datasize;
                        i40iw_handle_rcv_mpa(cm_node, rbuf);
                }
                break;
        case I40IW_CM_STATE_ESTABLISHED:
                i40iw_cleanup_retrans_entry(cm_node);
                if (datasize) {
                        cm_node->tcp_cntxt.rcv_nxt = inc_sequence + datasize;
                        i40iw_handle_rcv_mpa(cm_node, rbuf);
                }
                break;
        case I40IW_CM_STATE_MPAREQ_SENT:
                cm_node->tcp_cntxt.rem_ack_num = ntohl(tcph->ack_seq);
                if (datasize) {
                        cm_node->tcp_cntxt.rcv_nxt = inc_sequence + datasize;
                        cm_node->ack_rcvd = false;
                        i40iw_handle_rcv_mpa(cm_node, rbuf);
                } else {
                        cm_node->ack_rcvd = true;
                }
                break;
        case I40IW_CM_STATE_LISTENING:
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_CLOSED;
                i40iw_send_reset(cm_node);
                break;
        case I40IW_CM_STATE_CLOSED:
                i40iw_cleanup_retrans_entry(cm_node);
                atomic_inc(&cm_node->ref_count);
                i40iw_send_reset(cm_node);
                break;
        case I40IW_CM_STATE_LAST_ACK:
        case I40IW_CM_STATE_CLOSING:
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_CLOSED;
                if (!cm_node->accept_pend)
                        cm_node->cm_id->rem_ref(cm_node->cm_id);
                i40iw_rem_ref_cm_node(cm_node);
                break;
        case I40IW_CM_STATE_FIN_WAIT1:
                i40iw_cleanup_retrans_entry(cm_node);
                cm_node->state = I40IW_CM_STATE_FIN_WAIT2;
                break;
        case I40IW_CM_STATE_SYN_SENT:
        case I40IW_CM_STATE_FIN_WAIT2:
        case I40IW_CM_STATE_OFFLOADED:
        case I40IW_CM_STATE_MPAREQ_RCVD:
        case I40IW_CM_STATE_UNKNOWN:
        default:
                i40iw_cleanup_retrans_entry(cm_node);
                break;
        }
        return ret;
}

/**
 * i40iw_process_packet - process cm packet
 * @cm_node: connection's node
 * @rbuf: receive buffer
 */
static void i40iw_process_packet(struct i40iw_cm_node *cm_node,
                                 struct i40iw_puda_buf *rbuf)
{
        enum i40iw_tcpip_pkt_type pkt_type = I40IW_PKT_TYPE_UNKNOWN;
        struct tcphdr *tcph = (struct tcphdr *)rbuf->tcph;
        u32 fin_set = 0;
        int ret;

        if (tcph->rst) {
                pkt_type = I40IW_PKT_TYPE_RST;
        } else if (tcph->syn) {
                pkt_type = I40IW_PKT_TYPE_SYN;
                if (tcph->ack)
                        pkt_type = I40IW_PKT_TYPE_SYNACK;
        } else if (tcph->ack) {
                pkt_type = I40IW_PKT_TYPE_ACK;
        }
        if (tcph->fin)
                fin_set = 1;

        switch (pkt_type) {
        case I40IW_PKT_TYPE_SYN:
                i40iw_handle_syn_pkt(cm_node, rbuf);
                break;
        case I40IW_PKT_TYPE_SYNACK:
                i40iw_handle_synack_pkt(cm_node, rbuf);
                break;
        case I40IW_PKT_TYPE_ACK:
                ret = i40iw_handle_ack_pkt(cm_node, rbuf);
                if (fin_set && !ret)
                        i40iw_handle_fin_pkt(cm_node);
                break;
        case I40IW_PKT_TYPE_RST:
                i40iw_handle_rst_pkt(cm_node, rbuf);
                break;
        default:
                if (fin_set &&
                    (!i40iw_check_seq(cm_node, (struct tcphdr *)rbuf->tcph)))
                        i40iw_handle_fin_pkt(cm_node);
                break;
        }
}

/**
 * i40iw_make_listen_node - create a listen node with params
 * @cm_core: cm's core
 * @iwdev: iwarp device structure
 * @cm_info: quad info for connection
 */
static struct i40iw_cm_listener *i40iw_make_listen_node(
                                        struct i40iw_cm_core *cm_core,
                                        struct i40iw_device *iwdev,
                                        struct i40iw_cm_info *cm_info)
{
        struct i40iw_cm_listener *listener;
        unsigned long flags;

        /* cannot have multiple matching listeners */
        listener = i40iw_find_listener(cm_core, cm_info->loc_addr,
                                       cm_info->loc_port,
                                       cm_info->vlan_id,
                                       I40IW_CM_LISTENER_EITHER_STATE);
        if (listener &&
            (listener->listener_state == I40IW_CM_LISTENER_ACTIVE_STATE)) {
                atomic_dec(&listener->ref_count);
                i40iw_debug(cm_core->dev,
                            I40IW_DEBUG_CM,
                            "Not creating listener since it already exists\n");
                return NULL;
        }

        if (!listener) {
                /* create a CM listen node (1/2 node to compare incoming traffic to) */
                listener = kzalloc(sizeof(*listener), GFP_KERNEL);
                if (!listener)
                        return NULL;
                cm_core->stats_listen_nodes_created++;
                memcpy(listener->loc_addr, cm_info->loc_addr, sizeof(listener->loc_addr));
                listener->loc_port = cm_info->loc_port;

                INIT_LIST_HEAD(&listener->child_listen_list);

                atomic_set(&listener->ref_count, 1);
        } else {
                listener->reused_node = 1;
        }

        listener->cm_id = cm_info->cm_id;
        listener->ipv4 = cm_info->ipv4;
        listener->vlan_id = cm_info->vlan_id;
        atomic_set(&listener->pend_accepts_cnt, 0);
        listener->cm_core = cm_core;
        listener->iwdev = iwdev;

        listener->backlog = cm_info->backlog;
        listener->listener_state = I40IW_CM_LISTENER_ACTIVE_STATE;

        if (!listener->reused_node) {
                spin_lock_irqsave(&cm_core->listen_list_lock, flags);
                list_add(&listener->list, &cm_core->listen_nodes);
                spin_unlock_irqrestore(&cm_core->listen_list_lock, flags);
        }

        return listener;
}

/**
 * i40iw_create_cm_node - make a connection node with params
 * @cm_core: cm's core
 * @iwdev: iwarp device structure
 * @conn_param: upper layer connection parameters
 * @cm_info: quad info for connection
 */
static struct i40iw_cm_node *i40iw_create_cm_node(
                                        struct i40iw_cm_core *cm_core,
                                        struct i40iw_device *iwdev,
                                        struct iw_cm_conn_param *conn_param,
                                        struct i40iw_cm_info *cm_info)
{
        struct i40iw_cm_node *cm_node;
        struct i40iw_cm_listener *loopback_remotelistener;
        struct i40iw_cm_node *loopback_remotenode;
        struct i40iw_cm_info loopback_cm_info;

        u16 private_data_len = conn_param->private_data_len;
        const void *private_data = conn_param->private_data;

        /* create a CM connection node */
        cm_node = i40iw_make_cm_node(cm_core, iwdev, cm_info, NULL);
        if (!cm_node)
                return ERR_PTR(-ENOMEM);
        /* set our node side to client (active) side */
        cm_node->tcp_cntxt.client = 1;
        cm_node->tcp_cntxt.rcv_wscale = I40IW_CM_DEFAULT_RCV_WND_SCALE;

        i40iw_record_ird_ord(cm_node, conn_param->ird, conn_param->ord);

        if (!memcmp(cm_info->loc_addr, cm_info->rem_addr, sizeof(cm_info->loc_addr))) {
                loopback_remotelistener = i40iw_find_listener(
                                                cm_core,
                                                cm_info->rem_addr,
                                                cm_node->rem_port,
                                                cm_node->vlan_id,
                                                I40IW_CM_LISTENER_ACTIVE_STATE);
                if (!loopback_remotelistener) {
                        i40iw_rem_ref_cm_node(cm_node);
                        return ERR_PTR(-ECONNREFUSED);
                } else {
                        loopback_cm_info = *cm_info;
                        loopback_cm_info.loc_port = cm_info->rem_port;
                        loopback_cm_info.rem_port = cm_info->loc_port;
                        loopback_cm_info.cm_id = loopback_remotelistener->cm_id;
                        loopback_cm_info.ipv4 = cm_info->ipv4;
                        loopback_remotenode = i40iw_make_cm_node(cm_core,
                                                                 iwdev,
                                                                 &loopback_cm_info,
                                                                 loopback_remotelistener);
                        if (!loopback_remotenode) {
                                i40iw_rem_ref_cm_node(cm_node);
                                return ERR_PTR(-ENOMEM);
                        }
                        cm_core->stats_loopbacks++;
                        loopback_remotenode->loopbackpartner = cm_node;
                        loopback_remotenode->tcp_cntxt.rcv_wscale =
                                I40IW_CM_DEFAULT_RCV_WND_SCALE;
                        cm_node->loopbackpartner = loopback_remotenode;
                        memcpy(loopback_remotenode->pdata_buf, private_data,
                               private_data_len);
                        loopback_remotenode->pdata.size = private_data_len;

                        if (loopback_remotenode->ord_size > cm_node->ird_size)
                                loopback_remotenode->ord_size =
                                        cm_node->ird_size;

                        cm_node->state = I40IW_CM_STATE_OFFLOADED;
                        cm_node->tcp_cntxt.rcv_nxt =
                                loopback_remotenode->tcp_cntxt.loc_seq_num;
                        loopback_remotenode->tcp_cntxt.rcv_nxt =
                                cm_node->tcp_cntxt.loc_seq_num;
                        cm_node->tcp_cntxt.max_snd_wnd =
                                loopback_remotenode->tcp_cntxt.rcv_wnd;
                        loopback_remotenode->tcp_cntxt.max_snd_wnd = cm_node->tcp_cntxt.rcv_wnd;
                        cm_node->tcp_cntxt.snd_wnd = loopback_remotenode->tcp_cntxt.rcv_wnd;
                        loopback_remotenode->tcp_cntxt.snd_wnd = cm_node->tcp_cntxt.rcv_wnd;
                        cm_node->tcp_cntxt.snd_wscale = loopback_remotenode->tcp_cntxt.rcv_wscale;
                        loopback_remotenode->tcp_cntxt.snd_wscale = cm_node->tcp_cntxt.rcv_wscale;
                }
                return cm_node;
        }

        cm_node->pdata.size = private_data_len;