/*
 * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
 * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
 * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
 * Copyright (c) 2005-2006 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
 * OpenIB.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/completion.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/mutex.h>
#include <linux/random.h>
#include <linux/igmp.h>
#include <linux/idr.h>
#include <linux/inetdevice.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <net/route.h>

#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/tcp.h>
#include <net/ipv6.h>
#include <net/ip_fib.h>
#include <net/ip6_route.h>

#include <rdma/rdma_cm.h>
#include <rdma/rdma_cm_ib.h>
#include <rdma/rdma_netlink.h>
#include <rdma/ib.h>
#include <rdma/ib_cache.h>
#include <rdma/ib_cm.h>
#include <rdma/ib_sa.h>
#include <rdma/iw_cm.h>

#include "core_priv.h"
#include "cma_priv.h"

MODULE_AUTHOR("Sean Hefty");
MODULE_DESCRIPTION("Generic RDMA CM Agent");
MODULE_LICENSE("Dual BSD/GPL");

#define CMA_CM_RESPONSE_TIMEOUT 20
#define CMA_QUERY_CLASSPORT_INFO_TIMEOUT 3000
#define CMA_MAX_CM_RETRIES 15
#define CMA_CM_MRA_SETTING (IB_CM_MRA_FLAG_DELAY | 24)
#define CMA_IBOE_PACKET_LIFETIME 18
#define CMA_PREFERRED_ROCE_GID_TYPE IB_GID_TYPE_ROCE_UDP_ENCAP

static const char * const cma_events[] = {
        [RDMA_CM_EVENT_ADDR_RESOLVED]    = "address resolved",
        [RDMA_CM_EVENT_ADDR_ERROR]       = "address error",
        [RDMA_CM_EVENT_ROUTE_RESOLVED]   = "route resolved ",
        [RDMA_CM_EVENT_ROUTE_ERROR]      = "route error",
        [RDMA_CM_EVENT_CONNECT_REQUEST]  = "connect request",
        [RDMA_CM_EVENT_CONNECT_RESPONSE] = "connect response",
        [RDMA_CM_EVENT_CONNECT_ERROR]    = "connect error",
        [RDMA_CM_EVENT_UNREACHABLE]      = "unreachable",
        [RDMA_CM_EVENT_REJECTED]         = "rejected",
        [RDMA_CM_EVENT_ESTABLISHED]      = "established",
        [RDMA_CM_EVENT_DISCONNECTED]     = "disconnected",
        [RDMA_CM_EVENT_DEVICE_REMOVAL]   = "device removal",
        [RDMA_CM_EVENT_MULTICAST_JOIN]   = "multicast join",
        [RDMA_CM_EVENT_MULTICAST_ERROR]  = "multicast error",
        [RDMA_CM_EVENT_ADDR_CHANGE]      = "address change",
        [RDMA_CM_EVENT_TIMEWAIT_EXIT]    = "timewait exit",
};

const char *__attribute_const__ rdma_event_msg(enum rdma_cm_event_type event)
{
        size_t index = event;

        return (index < ARRAY_SIZE(cma_events) && cma_events[index]) ?
                        cma_events[index] : "unrecognized event";
}
EXPORT_SYMBOL(rdma_event_msg);

const char *__attribute_const__ rdma_reject_msg(struct rdma_cm_id *id,
                                                int reason)
{
        if (rdma_ib_or_roce(id->device, id->port_num))
                return ibcm_reject_msg(reason);

        if (rdma_protocol_iwarp(id->device, id->port_num))
                return iwcm_reject_msg(reason);

        WARN_ON_ONCE(1);
        return "unrecognized transport";
}
EXPORT_SYMBOL(rdma_reject_msg);

bool rdma_is_consumer_reject(struct rdma_cm_id *id, int reason)
{
        if (rdma_ib_or_roce(id->device, id->port_num))
                return reason == IB_CM_REJ_CONSUMER_DEFINED;

        if (rdma_protocol_iwarp(id->device, id->port_num))
                return reason == -ECONNREFUSED;

        WARN_ON_ONCE(1);
        return false;
}
EXPORT_SYMBOL(rdma_is_consumer_reject);

const void *rdma_consumer_reject_data(struct rdma_cm_id *id,
                                      struct rdma_cm_event *ev, u8 *data_len)
{
        const void *p;

        if (rdma_is_consumer_reject(id, ev->status)) {
                *data_len = ev->param.conn.private_data_len;
                p = ev->param.conn.private_data;
        } else {
                *data_len = 0;
                p = NULL;
        }
        return p;
}
EXPORT_SYMBOL(rdma_consumer_reject_data);

static void cma_add_one(struct ib_device *device);
static void cma_remove_one(struct ib_device *device, void *client_data);

static struct ib_client cma_client = {
        .name   = "cma",
        .add    = cma_add_one,
        .remove = cma_remove_one
};

static struct ib_sa_client sa_client;
static struct rdma_addr_client addr_client;
static LIST_HEAD(dev_list);
static LIST_HEAD(listen_any_list);
static DEFINE_MUTEX(lock);
static struct workqueue_struct *cma_wq;
static unsigned int cma_pernet_id;

struct cma_pernet {
        struct idr tcp_ps;
        struct idr udp_ps;
        struct idr ipoib_ps;
        struct idr ib_ps;
};

static struct cma_pernet *cma_pernet(struct net *net)
{
        return net_generic(net, cma_pernet_id);
}

static struct idr *cma_pernet_idr(struct net *net, enum rdma_ucm_port_space ps)
{
        struct cma_pernet *pernet = cma_pernet(net);

        switch (ps) {
        case RDMA_PS_TCP:
                return &pernet->tcp_ps;
        case RDMA_PS_UDP:
                return &pernet->udp_ps;
        case RDMA_PS_IPOIB:
                return &pernet->ipoib_ps;
        case RDMA_PS_IB:
                return &pernet->ib_ps;
        default:
                return NULL;
        }
}

struct cma_device {
        struct list_head        list;
        struct ib_device        *device;
        struct completion       comp;
        atomic_t                refcount;
        struct list_head        id_list;
        enum ib_gid_type        *default_gid_type;
        u8                      *default_roce_tos;
};

struct rdma_bind_list {
        enum rdma_ucm_port_space ps;
        struct hlist_head       owners;
        unsigned short          port;
};

struct class_port_info_context {
        struct ib_class_port_info       *class_port_info;
        struct ib_device                *device;
        struct completion               done;
        struct ib_sa_query              *sa_query;
        u8                              port_num;
};

static int cma_ps_alloc(struct net *net, enum rdma_ucm_port_space ps,
                        struct rdma_bind_list *bind_list, int snum)
{
        struct idr *idr = cma_pernet_idr(net, ps);

        return idr_alloc(idr, bind_list, snum, snum + 1, GFP_KERNEL);
}

static struct rdma_bind_list *cma_ps_find(struct net *net,
                                          enum rdma_ucm_port_space ps, int snum)
{
        struct idr *idr = cma_pernet_idr(net, ps);

        return idr_find(idr, snum);
}

static void cma_ps_remove(struct net *net, enum rdma_ucm_port_space ps,
                          int snum)
{
        struct idr *idr = cma_pernet_idr(net, ps);

        idr_remove(idr, snum);
}

enum {
        CMA_OPTION_AFONLY,
};

void cma_ref_dev(struct cma_device *cma_dev)
{
        atomic_inc(&cma_dev->refcount);
}

struct cma_device *cma_enum_devices_by_ibdev(cma_device_filter  filter,
                                             void               *cookie)
{
        struct cma_device *cma_dev;
        struct cma_device *found_cma_dev = NULL;

        mutex_lock(&lock);

        list_for_each_entry(cma_dev, &dev_list, list)
                if (filter(cma_dev->device, cookie)) {
                        found_cma_dev = cma_dev;
                        break;
                }

        if (found_cma_dev)
                cma_ref_dev(found_cma_dev);
        mutex_unlock(&lock);
        return found_cma_dev;
}

int cma_get_default_gid_type(struct cma_device *cma_dev,
                             unsigned int port)
{
        if (!rdma_is_port_valid(cma_dev->device, port))
                return -EINVAL;

        return cma_dev->default_gid_type[port - rdma_start_port(cma_dev->device)];
}

int cma_set_default_gid_type(struct cma_device *cma_dev,
                             unsigned int port,
                             enum ib_gid_type default_gid_type)
{
        unsigned long supported_gids;

        if (!rdma_is_port_valid(cma_dev->device, port))
                return -EINVAL;

        supported_gids = roce_gid_type_mask_support(cma_dev->device, port);

        if (!(supported_gids & 1 << default_gid_type))
                return -EINVAL;

        cma_dev->default_gid_type[port - rdma_start_port(cma_dev->device)] =
                default_gid_type;

        return 0;
}

int cma_get_default_roce_tos(struct cma_device *cma_dev, unsigned int port)
{
        if (!rdma_is_port_valid(cma_dev->device, port))
                return -EINVAL;

        return cma_dev->default_roce_tos[port - rdma_start_port(cma_dev->device)];
}

int cma_set_default_roce_tos(struct cma_device *cma_dev, unsigned int port,
                             u8 default_roce_tos)
{
        if (!rdma_is_port_valid(cma_dev->device, port))
                return -EINVAL;

        cma_dev->default_roce_tos[port - rdma_start_port(cma_dev->device)] =
                 default_roce_tos;

        return 0;
}
struct ib_device *cma_get_ib_dev(struct cma_device *cma_dev)
{
        return cma_dev->device;
}

/*
 * Device removal can occur at anytime, so we need extra handling to
 * serialize notifying the user of device removal with other callbacks.
 * We do this by disabling removal notification while a callback is in process,
 * and reporting it after the callback completes.
 */

struct cma_multicast {
        struct rdma_id_private *id_priv;
        union {
                struct ib_sa_multicast *ib;
        } multicast;
        struct list_head        list;
        void                    *context;
        struct sockaddr_storage addr;
        struct kref             mcref;
        bool                    igmp_joined;
        u8                      join_state;
};

struct cma_work {
        struct work_struct      work;
        struct rdma_id_private  *id;
        enum rdma_cm_state      old_state;
        enum rdma_cm_state      new_state;
        struct rdma_cm_event    event;
};

struct cma_ndev_work {
        struct work_struct      work;
        struct rdma_id_private  *id;
        struct rdma_cm_event    event;
};

struct iboe_mcast_work {
        struct work_struct       work;
        struct rdma_id_private  *id;
        struct cma_multicast    *mc;
};

union cma_ip_addr {
        struct in6_addr ip6;
        struct {
                __be32 pad[3];
                __be32 addr;
        } ip4;
};

struct cma_hdr {
        u8 cma_version;
        u8 ip_version;  /* IP version: 7:4 */
        __be16 port;
        union cma_ip_addr src_addr;
        union cma_ip_addr dst_addr;
};

#define CMA_VERSION 0x00

struct cma_req_info {
        struct sockaddr_storage listen_addr_storage;
        struct sockaddr_storage src_addr_storage;
        struct ib_device *device;
        int port;
        union ib_gid local_gid;
        __be64 service_id;
        u16 pkey;
        bool has_gid:1;
};

static int cma_comp(struct rdma_id_private *id_priv, enum rdma_cm_state comp)
{
        unsigned long flags;
        int ret;

        spin_lock_irqsave(&id_priv->lock, flags);
        ret = (id_priv->state == comp);
        spin_unlock_irqrestore(&id_priv->lock, flags);
        return ret;
}

static int cma_comp_exch(struct rdma_id_private *id_priv,
                         enum rdma_cm_state comp, enum rdma_cm_state exch)
{
        unsigned long flags;
        int ret;

        spin_lock_irqsave(&id_priv->lock, flags);
        if ((ret = (id_priv->state == comp)))
                id_priv->state = exch;
        spin_unlock_irqrestore(&id_priv->lock, flags);
        return ret;
}

static enum rdma_cm_state cma_exch(struct rdma_id_private *id_priv,
                                   enum rdma_cm_state exch)
{
        unsigned long flags;
        enum rdma_cm_state old;

        spin_lock_irqsave(&id_priv->lock, flags);
        old = id_priv->state;
        id_priv->state = exch;
        spin_unlock_irqrestore(&id_priv->lock, flags);
        return old;
}

static inline u8 cma_get_ip_ver(const struct cma_hdr *hdr)
{
        return hdr->ip_version >> 4;
}

static inline void cma_set_ip_ver(struct cma_hdr *hdr, u8 ip_ver)
{
        hdr->ip_version = (ip_ver << 4) | (hdr->ip_version & 0xF);
}

static int cma_igmp_send(struct net_device *ndev, union ib_gid *mgid, bool join)
{
        struct in_device *in_dev = NULL;

        if (ndev) {
                rtnl_lock();
                in_dev = __in_dev_get_rtnl(ndev);
                if (in_dev) {
                        if (join)
                                ip_mc_inc_group(in_dev,
                                                *(__be32 *)(mgid->raw + 12));
                        else
                                ip_mc_dec_group(in_dev,
                                                *(__be32 *)(mgid->raw + 12));
                }
                rtnl_unlock();
        }
        return (in_dev) ? 0 : -ENODEV;
}

static void _cma_attach_to_dev(struct rdma_id_private *id_priv,
                               struct cma_device *cma_dev)
{
        cma_ref_dev(cma_dev);
        id_priv->cma_dev = cma_dev;
        id_priv->gid_type = 0;
        id_priv->id.device = cma_dev->device;
        id_priv->id.route.addr.dev_addr.transport =
                rdma_node_get_transport(cma_dev->device->node_type);
        list_add_tail(&id_priv->list, &cma_dev->id_list);
        id_priv->res.type = RDMA_RESTRACK_CM_ID;
        rdma_restrack_add(&id_priv->res);
}

static void cma_attach_to_dev(struct rdma_id_private *id_priv,
                              struct cma_device *cma_dev)
{
        _cma_attach_to_dev(id_priv, cma_dev);
        id_priv->gid_type =
                cma_dev->default_gid_type[id_priv->id.port_num -
                                          rdma_start_port(cma_dev->device)];
}

void cma_deref_dev(struct cma_device *cma_dev)
{
        if (atomic_dec_and_test(&cma_dev->refcount))
                complete(&cma_dev->comp);
}

static inline void release_mc(struct kref *kref)
{
        struct cma_multicast *mc = container_of(kref, struct cma_multicast, mcref);

        kfree(mc->multicast.ib);
        kfree(mc);
}

static void cma_release_dev(struct rdma_id_private *id_priv)
{
        mutex_lock(&lock);
        list_del(&id_priv->list);
        cma_deref_dev(id_priv->cma_dev);
        id_priv->cma_dev = NULL;
        mutex_unlock(&lock);
}

static inline struct sockaddr *cma_src_addr(struct rdma_id_private *id_priv)
{
        return (struct sockaddr *) &id_priv->id.route.addr.src_addr;
}

static inline struct sockaddr *cma_dst_addr(struct rdma_id_private *id_priv)
{
        return (struct sockaddr *) &id_priv->id.route.addr.dst_addr;
}

static inline unsigned short cma_family(struct rdma_id_private *id_priv)
{
        return id_priv->id.route.addr.src_addr.ss_family;
}

static int cma_set_qkey(struct rdma_id_private *id_priv, u32 qkey)
{
        struct ib_sa_mcmember_rec rec;
        int ret = 0;

        if (id_priv->qkey) {
                if (qkey && id_priv->qkey != qkey)
                        return -EINVAL;
                return 0;
        }

        if (qkey) {
                id_priv->qkey = qkey;
                return 0;
        }

        switch (id_priv->id.ps) {
        case RDMA_PS_UDP:
        case RDMA_PS_IB:
                id_priv->qkey = RDMA_UDP_QKEY;
                break;
        case RDMA_PS_IPOIB:
                ib_addr_get_mgid(&id_priv->id.route.addr.dev_addr, &rec.mgid);
                ret = ib_sa_get_mcmember_rec(id_priv->id.device,
                                             id_priv->id.port_num, &rec.mgid,
                                             &rec);
                if (!ret)
                        id_priv->qkey = be32_to_cpu(rec.qkey);
                break;
        default:
                break;
        }
        return ret;
}

static void cma_translate_ib(struct sockaddr_ib *sib, struct rdma_dev_addr *dev_addr)
{
        dev_addr->dev_type = ARPHRD_INFINIBAND;
        rdma_addr_set_sgid(dev_addr, (union ib_gid *) &sib->sib_addr);
        ib_addr_set_pkey(dev_addr, ntohs(sib->sib_pkey));
}

static int cma_translate_addr(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
{
        int ret;

        if (addr->sa_family != AF_IB) {
                ret = rdma_translate_ip(addr, dev_addr);
        } else {
                cma_translate_ib((struct sockaddr_ib *) addr, dev_addr);
                ret = 0;
        }

        return ret;
}

static inline int cma_validate_port(struct ib_device *device, u8 port,
                                    enum ib_gid_type gid_type,
                                    union ib_gid *gid,
                                    struct rdma_id_private *id_priv)
{
        struct rdma_dev_addr *dev_addr = &id_priv->id.route.addr.dev_addr;
        int bound_if_index = dev_addr->bound_dev_if;
        int dev_type = dev_addr->dev_type;
        struct net_device *ndev = NULL;
        int ret = -ENODEV;

        if ((dev_type == ARPHRD_INFINIBAND) && !rdma_protocol_ib(device, port))
                return ret;

        if ((dev_type != ARPHRD_INFINIBAND) && rdma_protocol_ib(device, port))
                return ret;

        if (dev_type == ARPHRD_ETHER && rdma_protocol_roce(device, port)) {
                ndev = dev_get_by_index(dev_addr->net, bound_if_index);
                if (!ndev)
                        return ret;
        } else {
                gid_type = IB_GID_TYPE_IB;
        }

        ret = ib_find_cached_gid_by_port(device, gid, gid_type, port,
                                         ndev, NULL);

        if (ndev)
                dev_put(ndev);

        return ret;
}

static int cma_acquire_dev(struct rdma_id_private *id_priv,
                           struct rdma_id_private *listen_id_priv)
{
        struct rdma_dev_addr *dev_addr = &id_priv->id.route.addr.dev_addr;
        struct cma_device *cma_dev;
        union ib_gid gid, iboe_gid, *gidp;
        int ret = -ENODEV;
        u8 port;

        if (dev_addr->dev_type != ARPHRD_INFINIBAND &&
            id_priv->id.ps == RDMA_PS_IPOIB)
                return -EINVAL;

        mutex_lock(&lock);
        rdma_ip2gid((struct sockaddr *)&id_priv->id.route.addr.src_addr,
                    &iboe_gid);

        memcpy(&gid, dev_addr->src_dev_addr +
               rdma_addr_gid_offset(dev_addr), sizeof gid);

        if (listen_id_priv) {
                cma_dev = listen_id_priv->cma_dev;
                port = listen_id_priv->id.port_num;
                gidp = rdma_protocol_roce(cma_dev->device, port) ?
                       &iboe_gid : &gid;

                ret = cma_validate_port(cma_dev->device, port,
                                        rdma_protocol_ib(cma_dev->device, port) ?
                                        IB_GID_TYPE_IB :
                                        listen_id_priv->gid_type, gidp,
                                        id_priv);
                if (!ret) {
                        id_priv->id.port_num = port;
                        goto out;
                }
        }

        list_for_each_entry(cma_dev, &dev_list, list) {
                for (port = 1; port <= cma_dev->device->phys_port_cnt; ++port) {
                        if (listen_id_priv &&
                            listen_id_priv->cma_dev == cma_dev &&
                            listen_id_priv->id.port_num == port)
                                continue;

                        gidp = rdma_protocol_roce(cma_dev->device, port) ?
                               &iboe_gid : &gid;

                        ret = cma_validate_port(cma_dev->device, port,
                                                rdma_protocol_ib(cma_dev->device, port) ?
                                                IB_GID_TYPE_IB :
                                                cma_dev->default_gid_type[port - 1],
                                                gidp, id_priv);
                        if (!ret) {
                                id_priv->id.port_num = port;
                                goto out;
                        }
                }
        }

out:
        if (!ret)
                cma_attach_to_dev(id_priv, cma_dev);

        mutex_unlock(&lock);
        return ret;
}

/*
 * Select the source IB device and address to reach the destination IB address.
 */
static int cma_resolve_ib_dev(struct rdma_id_private *id_priv)
{
        struct cma_device *cma_dev, *cur_dev;
        struct sockaddr_ib *addr;
        union ib_gid gid, sgid, *dgid;
        u16 pkey, index;
        u8 p;
        enum ib_port_state port_state;
        int i;

        cma_dev = NULL;
        addr = (struct sockaddr_ib *) cma_dst_addr(id_priv);
        dgid = (union ib_gid *) &addr->sib_addr;
        pkey = ntohs(addr->sib_pkey);

        list_for_each_entry(cur_dev, &dev_list, list) {
                for (p = 1; p <= cur_dev->device->phys_port_cnt; ++p) {
                        if (!rdma_cap_af_ib(cur_dev->device, p))
                                continue;

                        if (ib_find_cached_pkey(cur_dev->device, p, pkey, &index))
                                continue;

                        if (ib_get_cached_port_state(cur_dev->device, p, &port_state))
                                continue;
                        for (i = 0; !ib_get_cached_gid(cur_dev->device, p, i,
                                                       &gid, NULL);
                             i++) {
                                if (!memcmp(&gid, dgid, sizeof(gid))) {
                                        cma_dev = cur_dev;
                                        sgid = gid;
                                        id_priv->id.port_num = p;
                                        goto found;
                                }

                                if (!cma_dev && (gid.global.subnet_prefix ==
                                    dgid->global.subnet_prefix) &&
                                    port_state == IB_PORT_ACTIVE) {
                                        cma_dev = cur_dev;
                                        sgid = gid;
                                        id_priv->id.port_num = p;
                                }
                        }
                }
        }

        if (!cma_dev)
                return -ENODEV;

found:
        cma_attach_to_dev(id_priv, cma_dev);
        addr = (struct sockaddr_ib *) cma_src_addr(id_priv);
        memcpy(&addr->sib_addr, &sgid, sizeof sgid);
        cma_translate_ib(addr, &id_priv->id.route.addr.dev_addr);
        return 0;
}

static void cma_deref_id(struct rdma_id_private *id_priv)
{
        if (atomic_dec_and_test(&id_priv->refcount))
                complete(&id_priv->comp);
}

struct rdma_cm_id *__rdma_create_id(struct net *net,
                                    rdma_cm_event_handler event_handler,
                                    void *context, enum rdma_ucm_port_space ps,
                                    enum ib_qp_type qp_type, const char *caller)
{
        struct rdma_id_private *id_priv;

        id_priv = kzalloc(sizeof *id_priv, GFP_KERNEL);
        if (!id_priv)
                return ERR_PTR(-ENOMEM);

        if (caller)
                id_priv->res.kern_name = caller;
        else
                rdma_restrack_set_task(&id_priv->res, current);
        id_priv->state = RDMA_CM_IDLE;
        id_priv->id.context = context;
        id_priv->id.event_handler = event_handler;
        id_priv->id.ps = ps;
        id_priv->id.qp_type = qp_type;
        id_priv->tos_set = false;
        spin_lock_init(&id_priv->lock);
        mutex_init(&id_priv->qp_mutex);
        init_completion(&id_priv->comp);
        atomic_set(&id_priv->refcount, 1);
        mutex_init(&id_priv->handler_mutex);
        INIT_LIST_HEAD(&id_priv->listen_list);
        INIT_LIST_HEAD(&id_priv->mc_list);
        get_random_bytes(&id_priv->seq_num, sizeof id_priv->seq_num);
        id_priv->id.route.addr.dev_addr.net = get_net(net);
        id_priv->seq_num &= 0x00ffffff;

        return &id_priv->id;
}
EXPORT_SYMBOL(__rdma_create_id);

static int cma_init_ud_qp(struct rdma_id_private *id_priv, struct ib_qp *qp)
{
        struct ib_qp_attr qp_attr;
        int qp_attr_mask, ret;

        qp_attr.qp_state = IB_QPS_INIT;
        ret = rdma_init_qp_attr(&id_priv->id, &qp_attr, &qp_attr_mask);
        if (ret)
                return ret;

        ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
        if (ret)
                return ret;

        qp_attr.qp_state = IB_QPS_RTR;
        ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
        if (ret)
                return ret;

        qp_attr.qp_state = IB_QPS_RTS;
        qp_attr.sq_psn = 0;
        ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE | IB_QP_SQ_PSN);

        return ret;
}

static int cma_init_conn_qp(struct rdma_id_private *id_priv, struct ib_qp *qp)
{
        struct ib_qp_attr qp_attr;
        int qp_attr_mask, ret;

        qp_attr.qp_state = IB_QPS_INIT;
        ret = rdma_init_qp_attr(&id_priv->id, &qp_attr, &qp_attr_mask);
        if (ret)
                return ret;

        return ib_modify_qp(qp, &qp_attr, qp_attr_mask);
}

int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
                   struct ib_qp_init_attr *qp_init_attr)
{
        struct rdma_id_private *id_priv;
        struct ib_qp *qp;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (id->device != pd->device)
                return -EINVAL;

        qp_init_attr->port_num = id->port_num;
        qp = ib_create_qp(pd, qp_init_attr);
        if (IS_ERR(qp))
                return PTR_ERR(qp);

        if (id->qp_type == IB_QPT_UD)
                ret = cma_init_ud_qp(id_priv, qp);
        else
                ret = cma_init_conn_qp(id_priv, qp);
        if (ret)
                goto err;

        id->qp = qp;
        id_priv->qp_num = qp->qp_num;
        id_priv->srq = (qp->srq != NULL);
        return 0;
err:
        ib_destroy_qp(qp);
        return ret;
}
EXPORT_SYMBOL(rdma_create_qp);

void rdma_destroy_qp(struct rdma_cm_id *id)
{
        struct rdma_id_private *id_priv;

        id_priv = container_of(id, struct rdma_id_private, id);
        mutex_lock(&id_priv->qp_mutex);
        ib_destroy_qp(id_priv->id.qp);
        id_priv->id.qp = NULL;
        mutex_unlock(&id_priv->qp_mutex);
}
EXPORT_SYMBOL(rdma_destroy_qp);

static int cma_modify_qp_rtr(struct rdma_id_private *id_priv,
                             struct rdma_conn_param *conn_param)
{
        struct ib_qp_attr qp_attr;
        int qp_attr_mask, ret;

        mutex_lock(&id_priv->qp_mutex);
        if (!id_priv->id.qp) {
                ret = 0;
                goto out;
        }

        /* Need to update QP attributes from default values. */
        qp_attr.qp_state = IB_QPS_INIT;
        ret = rdma_init_qp_attr(&id_priv->id, &qp_attr, &qp_attr_mask);
        if (ret)
                goto out;

        ret = ib_modify_qp(id_priv->id.qp, &qp_attr, qp_attr_mask);
        if (ret)
                goto out;

        qp_attr.qp_state = IB_QPS_RTR;
        ret = rdma_init_qp_attr(&id_priv->id, &qp_attr, &qp_attr_mask);
        if (ret)
                goto out;

        BUG_ON(id_priv->cma_dev->device != id_priv->id.device);

        if (conn_param)
                qp_attr.max_dest_rd_atomic = conn_param->responder_resources;
        ret = ib_modify_qp(id_priv->id.qp, &qp_attr, qp_attr_mask);
out:
        mutex_unlock(&id_priv->qp_mutex);
        return ret;
}

static int cma_modify_qp_rts(struct rdma_id_private *id_priv,
                             struct rdma_conn_param *conn_param)
{
        struct ib_qp_attr qp_attr;
        int qp_attr_mask, ret;

        mutex_lock(&id_priv->qp_mutex);
        if (!id_priv->id.qp) {
                ret = 0;
                goto out;
        }

        qp_attr.qp_state = IB_QPS_RTS;
        ret = rdma_init_qp_attr(&id_priv->id, &qp_attr, &qp_attr_mask);
        if (ret)
                goto out;

        if (conn_param)
                qp_attr.max_rd_atomic = conn_param->initiator_depth;
        ret = ib_modify_qp(id_priv->id.qp, &qp_attr, qp_attr_mask);
out:
        mutex_unlock(&id_priv->qp_mutex);
        return ret;
}

static int cma_modify_qp_err(struct rdma_id_private *id_priv)
{
        struct ib_qp_attr qp_attr;
        int ret;

        mutex_lock(&id_priv->qp_mutex);
        if (!id_priv->id.qp) {
                ret = 0;
                goto out;
        }

        qp_attr.qp_state = IB_QPS_ERR;
        ret = ib_modify_qp(id_priv->id.qp, &qp_attr, IB_QP_STATE);
out:
        mutex_unlock(&id_priv->qp_mutex);
        return ret;
}

static int cma_ib_init_qp_attr(struct rdma_id_private *id_priv,
                               struct ib_qp_attr *qp_attr, int *qp_attr_mask)
{
        struct rdma_dev_addr *dev_addr = &id_priv->id.route.addr.dev_addr;
        int ret;
        u16 pkey;

        if (rdma_cap_eth_ah(id_priv->id.device, id_priv->id.port_num))
                pkey = 0xffff;
        else
                pkey = ib_addr_get_pkey(dev_addr);

        ret = ib_find_cached_pkey(id_priv->id.device, id_priv->id.port_num,
                                  pkey, &qp_attr->pkey_index);
        if (ret)
                return ret;

        qp_attr->port_num = id_priv->id.port_num;
        *qp_attr_mask = IB_QP_STATE | IB_QP_PKEY_INDEX | IB_QP_PORT;

        if (id_priv->id.qp_type == IB_QPT_UD) {
                ret = cma_set_qkey(id_priv, 0);
                if (ret)
                        return ret;

                qp_attr->qkey = id_priv->qkey;
                *qp_attr_mask |= IB_QP_QKEY;
        } else {
                qp_attr->qp_access_flags = 0;
                *qp_attr_mask |= IB_QP_ACCESS_FLAGS;
        }
        return 0;
}

int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
                       int *qp_attr_mask)
{
        struct rdma_id_private *id_priv;
        int ret = 0;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (rdma_cap_ib_cm(id->device, id->port_num)) {
                if (!id_priv->cm_id.ib || (id_priv->id.qp_type == IB_QPT_UD))
                        ret = cma_ib_init_qp_attr(id_priv, qp_attr, qp_attr_mask);
                else
                        ret = ib_cm_init_qp_attr(id_priv->cm_id.ib, qp_attr,
                                                 qp_attr_mask);

                if (qp_attr->qp_state == IB_QPS_RTR)
                        qp_attr->rq_psn = id_priv->seq_num;
        } else if (rdma_cap_iw_cm(id->device, id->port_num)) {
                if (!id_priv->cm_id.iw) {
                        qp_attr->qp_access_flags = 0;
                        *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS;
                } else

                        ret = iw_cm_init_qp_attr(id_priv->cm_id.iw, qp_attr,
                                                 qp_attr_mask);
                qp_attr->port_num = id_priv->id.port_num;
                *qp_attr_mask |= IB_QP_PORT;
        } else
                ret = -ENOSYS;

        return ret;
}
EXPORT_SYMBOL(rdma_init_qp_attr);

static inline int cma_zero_addr(struct sockaddr *addr)
{
        switch (addr->sa_family) {
        case AF_INET:
                return ipv4_is_zeronet(((struct sockaddr_in *)addr)->sin_addr.s_addr);
        case AF_INET6:
                return ipv6_addr_any(&((struct sockaddr_in6 *) addr)->sin6_addr);
        case AF_IB:
                return ib_addr_any(&((struct sockaddr_ib *) addr)->sib_addr);
        default:
                return 0;
        }
}

static inline int cma_loopback_addr(struct sockaddr *addr)
{
        switch (addr->sa_family) {
        case AF_INET:
                return ipv4_is_loopback(((struct sockaddr_in *) addr)->sin_addr.s_addr);
        case AF_INET6:
                return ipv6_addr_loopback(&((struct sockaddr_in6 *) addr)->sin6_addr);
        case AF_IB:
                return ib_addr_loopback(&((struct sockaddr_ib *) addr)->sib_addr);
        default:
                return 0;
        }
}

static inline int cma_any_addr(struct sockaddr *addr)
{
        return cma_zero_addr(addr) || cma_loopback_addr(addr);
}

static int cma_addr_cmp(struct sockaddr *src, struct sockaddr *dst)
{
        if (src->sa_family != dst->sa_family)
                return -1;

        switch (src->sa_family) {
        case AF_INET:
                return ((struct sockaddr_in *) src)->sin_addr.s_addr !=
                       ((struct sockaddr_in *) dst)->sin_addr.s_addr;
        case AF_INET6:
                return ipv6_addr_cmp(&((struct sockaddr_in6 *) src)->sin6_addr,
                                     &((struct sockaddr_in6 *) dst)->sin6_addr);
        default:
                return ib_addr_cmp(&((struct sockaddr_ib *) src)->sib_addr,
                                   &((struct sockaddr_ib *) dst)->sib_addr);
        }
}

static __be16 cma_port(struct sockaddr *addr)
{
        struct sockaddr_ib *sib;

        switch (addr->sa_family) {
        case AF_INET:
                return ((struct sockaddr_in *) addr)->sin_port;
        case AF_INET6:
                return ((struct sockaddr_in6 *) addr)->sin6_port;
        case AF_IB:
                sib = (struct sockaddr_ib *) addr;
                return htons((u16) (be64_to_cpu(sib->sib_sid) &
                                    be64_to_cpu(sib->sib_sid_mask)));
        default:
                return 0;
        }
}

static inline int cma_any_port(struct sockaddr *addr)
{
        return !cma_port(addr);
}

static void cma_save_ib_info(struct sockaddr *src_addr,
                             struct sockaddr *dst_addr,
                             struct rdma_cm_id *listen_id,
                             struct sa_path_rec *path)
{
        struct sockaddr_ib *listen_ib, *ib;

        listen_ib = (struct sockaddr_ib *) &listen_id->route.addr.src_addr;
        if (src_addr) {
                ib = (struct sockaddr_ib *)src_addr;
                ib->sib_family = AF_IB;
                if (path) {
                        ib->sib_pkey = path->pkey;
                        ib->sib_flowinfo = path->flow_label;
                        memcpy(&ib->sib_addr, &path->sgid, 16);
                        ib->sib_sid = path->service_id;
                        ib->sib_scope_id = 0;
                } else {
                        ib->sib_pkey = listen_ib->sib_pkey;
                        ib->sib_flowinfo = listen_ib->sib_flowinfo;
                        ib->sib_addr = listen_ib->sib_addr;
                        ib->sib_sid = listen_ib->sib_sid;
                        ib->sib_scope_id = listen_ib->sib_scope_id;
                }
                ib->sib_sid_mask = cpu_to_be64(0xffffffffffffffffULL);
        }
        if (dst_addr) {
                ib = (struct sockaddr_ib *)dst_addr;
                ib->sib_family = AF_IB;
                if (path) {
                        ib->sib_pkey = path->pkey;
                        ib->sib_flowinfo = path->flow_label;
                        memcpy(&ib->sib_addr, &path->dgid, 16);
                }
        }
}

static void cma_save_ip4_info(struct sockaddr_in *src_addr,
                              struct sockaddr_in *dst_addr,
                              struct cma_hdr *hdr,
                              __be16 local_port)
{
        if (src_addr) {
                *src_addr = (struct sockaddr_in) {
                        .sin_family = AF_INET,
                        .sin_addr.s_addr = hdr->dst_addr.ip4.addr,
                        .sin_port = local_port,
                };
        }

        if (dst_addr) {
                *dst_addr = (struct sockaddr_in) {
                        .sin_family = AF_INET,
                        .sin_addr.s_addr = hdr->src_addr.ip4.addr,
                        .sin_port = hdr->port,
                };
        }
}

static void cma_save_ip6_info(struct sockaddr_in6 *src_addr,
                              struct sockaddr_in6 *dst_addr,
                              struct cma_hdr *hdr,
                              __be16 local_port)
{
        if (src_addr) {
                *src_addr = (struct sockaddr_in6) {
                        .sin6_family = AF_INET6,
                        .sin6_addr = hdr->dst_addr.ip6,
                        .sin6_port = local_port,
                };
        }

        if (dst_addr) {
                *dst_addr = (struct sockaddr_in6) {
                        .sin6_family = AF_INET6,
                        .sin6_addr = hdr->src_addr.ip6,
                        .sin6_port = hdr->port,
                };
        }
}

static u16 cma_port_from_service_id(__be64 service_id)
{
        return (u16)be64_to_cpu(service_id);
}

static int cma_save_ip_info(struct sockaddr *src_addr,
                            struct sockaddr *dst_addr,
                            struct ib_cm_event *ib_event,
                            __be64 service_id)
{
        struct cma_hdr *hdr;
        __be16 port;

        hdr = ib_event->private_data;
        if (hdr->cma_version != CMA_VERSION)
                return -EINVAL;

        port = htons(cma_port_from_service_id(service_id));

        switch (cma_get_ip_ver(hdr)) {
        case 4:
                cma_save_ip4_info((struct sockaddr_in *)src_addr,
                                  (struct sockaddr_in *)dst_addr, hdr, port);
                break;
        case 6:
                cma_save_ip6_info((struct sockaddr_in6 *)src_addr,
                                  (struct sockaddr_in6 *)dst_addr, hdr, port);
                break;
        default:
                return -EAFNOSUPPORT;
        }

        return 0;
}

static int cma_save_net_info(struct sockaddr *src_addr,
                             struct sockaddr *dst_addr,
                             struct rdma_cm_id *listen_id,
                             struct ib_cm_event *ib_event,
                             sa_family_t sa_family, __be64 service_id)
{
        if (sa_family == AF_IB) {
                if (ib_event->event == IB_CM_REQ_RECEIVED)
                        cma_save_ib_info(src_addr, dst_addr, listen_id,
                                         ib_event->param.req_rcvd.primary_path);
                else if (ib_event->event == IB_CM_SIDR_REQ_RECEIVED)
                        cma_save_ib_info(src_addr, dst_addr, listen_id, NULL);
                return 0;
        }

        return cma_save_ip_info(src_addr, dst_addr, ib_event, service_id);
}

static int cma_save_req_info(const struct ib_cm_event *ib_event,
                             struct cma_req_info *req)
{
        const struct ib_cm_req_event_param *req_param =
                &ib_event->param.req_rcvd;
        const struct ib_cm_sidr_req_event_param *sidr_param =
                &ib_event->param.sidr_req_rcvd;

        switch (ib_event->event) {
        case IB_CM_REQ_RECEIVED:
                req->device     = req_param->listen_id->device;
                req->port       = req_param->port;
                memcpy(&req->local_gid, &req_param->primary_path->sgid,
                       sizeof(req->local_gid));
                req->has_gid    = true;
                req->service_id = req_param->primary_path->service_id;
                req->pkey       = be16_to_cpu(req_param->primary_path->pkey);
                if (req->pkey != req_param->bth_pkey)
                        pr_warn_ratelimited("RDMA CMA: got different BTH P_Key (0x%x) and primary path P_Key (0x%x)\n"
                                            "RDMA CMA: in the future this may cause the request to be dropped\n",
                                            req_param->bth_pkey, req->pkey);
                break;
        case IB_CM_SIDR_REQ_RECEIVED:
                req->device     = sidr_param->listen_id->device;
                req->port       = sidr_param->port;
                req->has_gid    = false;
                req->service_id = sidr_param->service_id;
                req->pkey       = sidr_param->pkey;
                if (req->pkey != sidr_param->bth_pkey)
                        pr_warn_ratelimited("RDMA CMA: got different BTH P_Key (0x%x) and SIDR request payload P_Key (0x%x)\n"
                                            "RDMA CMA: in the future this may cause the request to be dropped\n",
                                            sidr_param->bth_pkey, req->pkey);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static bool validate_ipv4_net_dev(struct net_device *net_dev,
                                  const struct sockaddr_in *dst_addr,
                                  const struct sockaddr_in *src_addr)
{
        __be32 daddr = dst_addr->sin_addr.s_addr,
               saddr = src_addr->sin_addr.s_addr;
        struct fib_result res;
        struct flowi4 fl4;
        int err;
        bool ret;

        if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
            ipv4_is_lbcast(daddr) || ipv4_is_zeronet(saddr) ||
            ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr) ||
            ipv4_is_loopback(saddr))
                return false;

        memset(&fl4, 0, sizeof(fl4));
        fl4.flowi4_iif = net_dev->ifindex;
        fl4.daddr = daddr;
        fl4.saddr = saddr;

        rcu_read_lock();
        err = fib_lookup(dev_net(net_dev), &fl4, &res, 0);
        ret = err == 0 && FIB_RES_DEV(res) == net_dev;
        rcu_read_unlock();

        return ret;
}

static bool validate_ipv6_net_dev(struct net_device *net_dev,
                                  const struct sockaddr_in6 *dst_addr,
                                  const struct sockaddr_in6 *src_addr)
{
#if IS_ENABLED(CONFIG_IPV6)
        const int strict = ipv6_addr_type(&dst_addr->sin6_addr) &
                           IPV6_ADDR_LINKLOCAL;
        struct rt6_info *rt = rt6_lookup(dev_net(net_dev), &dst_addr->sin6_addr,
                                         &src_addr->sin6_addr, net_dev->ifindex,
                                         NULL, strict);
        bool ret;

        if (!rt)
                return false;

        ret = rt->rt6i_idev->dev == net_dev;
        ip6_rt_put(rt);

        return ret;
#else
        return false;
#endif
}

static bool validate_net_dev(struct net_device *net_dev,
                             const struct sockaddr *daddr,
                             const struct sockaddr *saddr)
{
        const struct sockaddr_in *daddr4 = (const struct sockaddr_in *)daddr;
        const struct sockaddr_in *saddr4 = (const struct sockaddr_in *)saddr;
        const struct sockaddr_in6 *daddr6 = (const struct sockaddr_in6 *)daddr;
        const struct sockaddr_in6 *saddr6 = (const struct sockaddr_in6 *)saddr;

        switch (daddr->sa_family) {
        case AF_INET:
                return saddr->sa_family == AF_INET &&
                       validate_ipv4_net_dev(net_dev, daddr4, saddr4);

        case AF_INET6:
                return saddr->sa_family == AF_INET6 &&
                       validate_ipv6_net_dev(net_dev, daddr6, saddr6);

        default:
                return false;
        }
}

static struct net_device *cma_get_net_dev(struct ib_cm_event *ib_event,
                                          struct cma_req_info *req)
{
        struct sockaddr *listen_addr =
                        (struct sockaddr *)&req->listen_addr_storage;
        struct sockaddr *src_addr = (struct sockaddr *)&req->src_addr_storage;
        struct net_device *net_dev;
        const union ib_gid *gid = req->has_gid ? &req->local_gid : NULL;
        int err;

        err = cma_save_ip_info(listen_addr, src_addr, ib_event,
                               req->service_id);
        if (err)
                return ERR_PTR(err);

        net_dev = ib_get_net_dev_by_params(req->device, req->port, req->pkey,
                                           gid, listen_addr);
        if (!net_dev)
                return ERR_PTR(-ENODEV);

        return net_dev;
}

static enum rdma_ucm_port_space rdma_ps_from_service_id(__be64 service_id)
{
        return (be64_to_cpu(service_id) >> 16) & 0xffff;
}

static bool cma_match_private_data(struct rdma_id_private *id_priv,
                                   const struct cma_hdr *hdr)
{
        struct sockaddr *addr = cma_src_addr(id_priv);
        __be32 ip4_addr;
        struct in6_addr ip6_addr;

        if (cma_any_addr(addr) && !id_priv->afonly)
                return true;

        switch (addr->sa_family) {
        case AF_INET:
                ip4_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
                if (cma_get_ip_ver(hdr) != 4)
                        return false;
                if (!cma_any_addr(addr) &&
                    hdr->dst_addr.ip4.addr != ip4_addr)
                        return false;
                break;
        case AF_INET6:
                ip6_addr = ((struct sockaddr_in6 *)addr)->sin6_addr;
                if (cma_get_ip_ver(hdr) != 6)
                        return false;
                if (!cma_any_addr(addr) &&
                    memcmp(&hdr->dst_addr.ip6, &ip6_addr, sizeof(ip6_addr)))
                        return false;
                break;
        case AF_IB:
                return true;
        default:
                return false;
        }

        return true;
}

static bool cma_protocol_roce(const struct rdma_cm_id *id)
{
        struct ib_device *device = id->device;
        const int port_num = id->port_num ?: rdma_start_port(device);

        return rdma_protocol_roce(device, port_num);
}

static bool cma_match_net_dev(const struct rdma_cm_id *id,
                              const struct net_device *net_dev,
                              u8 port_num)
{
        const struct rdma_addr *addr = &id->route.addr;

        if (!net_dev)
                /* This request is an AF_IB request or a RoCE request */
                return (!id->port_num || id->port_num == port_num) &&
                       (addr->src_addr.ss_family == AF_IB ||
                        rdma_protocol_roce(id->device, port_num));

        return !addr->dev_addr.bound_dev_if ||
               (net_eq(dev_net(net_dev), addr->dev_addr.net) &&
                addr->dev_addr.bound_dev_if == net_dev->ifindex);
}

static struct rdma_id_private *cma_find_listener(
                const struct rdma_bind_list *bind_list,
                const struct ib_cm_id *cm_id,
                const struct ib_cm_event *ib_event,
                const struct cma_req_info *req,
                const struct net_device *net_dev)
{
        struct rdma_id_private *id_priv, *id_priv_dev;

        if (!bind_list)
                return ERR_PTR(-EINVAL);

        hlist_for_each_entry(id_priv, &bind_list->owners, node) {
                if (cma_match_private_data(id_priv, ib_event->private_data)) {
                        if (id_priv->id.device == cm_id->device &&
                            cma_match_net_dev(&id_priv->id, net_dev, req->port))
                                return id_priv;
                        list_for_each_entry(id_priv_dev,
                                            &id_priv->listen_list,
                                            listen_list) {
                                if (id_priv_dev->id.device == cm_id->device &&
                                    cma_match_net_dev(&id_priv_dev->id, net_dev, req->port))
                                        return id_priv_dev;
                        }
                }
        }

        return ERR_PTR(-EINVAL);
}

static struct rdma_id_private *cma_id_from_event(struct ib_cm_id *cm_id,
                                                 struct ib_cm_event *ib_event,
                                                 struct net_device **net_dev)
{
        struct cma_req_info req;
        struct rdma_bind_list *bind_list;
        struct rdma_id_private *id_priv;
        int err;

        err = cma_save_req_info(ib_event, &req);
        if (err)
                return ERR_PTR(err);

        *net_dev = cma_get_net_dev(ib_event, &req);
        if (IS_ERR(*net_dev)) {
                if (PTR_ERR(*net_dev) == -EAFNOSUPPORT) {
                        /* Assuming the protocol is AF_IB */
                        *net_dev = NULL;
                } else if (rdma_protocol_roce(req.device, req.port)) {
                        /* TODO find the net dev matching the request parameters
                         * through the RoCE GID table */
                        *net_dev = NULL;
                } else {
                        return ERR_CAST(*net_dev);
                }
        }

        /*
         * Net namespace might be getting deleted while route lookup,
         * cm_id lookup is in progress. Therefore, perform netdevice
         * validation, cm_id lookup under rcu lock.
         * RCU lock along with netdevice state check, synchronizes with
         * netdevice migrating to different net namespace and also avoids
         * case where net namespace doesn't get deleted while lookup is in
         * progress.
         * If the device state is not IFF_UP, its properties such as ifindex
         * and nd_net cannot be trusted to remain valid without rcu lock.
         * net/core/dev.c change_net_namespace() ensures to synchronize with
         * ongoing operations on net device after device is closed using
         * synchronize_net().
         */
        rcu_read_lock();
        if (*net_dev) {
                /*
                 * If netdevice is down, it is likely that it is administratively
                 * down or it might be migrating to different namespace.
                 * In that case avoid further processing, as the net namespace
                 * or ifindex may change.
                 */
                if (((*net_dev)->flags & IFF_UP) == 0) {
                        id_priv = ERR_PTR(-EHOSTUNREACH);
                        goto err;
                }

                if (!validate_net_dev(*net_dev,
                                 (struct sockaddr *)&req.listen_addr_storage,
                                 (struct sockaddr *)&req.src_addr_storage)) {
                        id_priv = ERR_PTR(-EHOSTUNREACH);
                        goto err;
                }
        }

        bind_list = cma_ps_find(*net_dev ? dev_net(*net_dev) : &init_net,
                                rdma_ps_from_service_id(req.service_id),
                                cma_port_from_service_id(req.service_id));
        id_priv = cma_find_listener(bind_list, cm_id, ib_event, &req, *net_dev);
err:
        rcu_read_unlock();
        if (IS_ERR(id_priv) && *net_dev) {
                dev_put(*net_dev);
                *net_dev = NULL;
        }
        return id_priv;
}

static inline u8 cma_user_data_offset(struct rdma_id_private *id_priv)
{
        return cma_family(id_priv) == AF_IB ? 0 : sizeof(struct cma_hdr);
}

static void cma_cancel_route(struct rdma_id_private *id_priv)
{
        if (rdma_cap_ib_sa(id_priv->id.device, id_priv->id.port_num)) {
                if (id_priv->query)
                        ib_sa_cancel_query(id_priv->query_id, id_priv->query);
        }
}

static void cma_cancel_listens(struct rdma_id_private *id_priv)
{
        struct rdma_id_private *dev_id_priv;

        /*
         * Remove from listen_any_list to prevent added devices from spawning
         * additional listen requests.
         */
        mutex_lock(&lock);
        list_del(&id_priv->list);

        while (!list_empty(&id_priv->listen_list)) {
                dev_id_priv = list_entry(id_priv->listen_list.next,
                                         struct rdma_id_private, listen_list);
                /* sync with device removal to avoid duplicate destruction */
                list_del_init(&dev_id_priv->list);
                list_del(&dev_id_priv->listen_list);
                mutex_unlock(&lock);

                rdma_destroy_id(&dev_id_priv->id);
                mutex_lock(&lock);
        }
        mutex_unlock(&lock);
}

static void cma_cancel_operation(struct rdma_id_private *id_priv,
                                 enum rdma_cm_state state)
{
        switch (state) {
        case RDMA_CM_ADDR_QUERY:
                rdma_addr_cancel(&id_priv->id.route.addr.dev_addr);
                break;
        case RDMA_CM_ROUTE_QUERY:
                cma_cancel_route(id_priv);
                break;
        case RDMA_CM_LISTEN:
                if (cma_any_addr(cma_src_addr(id_priv)) && !id_priv->cma_dev)
                        cma_cancel_listens(id_priv);
                break;
        default:
                break;
        }
}

static void cma_release_port(struct rdma_id_private *id_priv)
{
        struct rdma_bind_list *bind_list = id_priv->bind_list;
        struct net *net = id_priv->id.route.addr.dev_addr.net;

        if (!bind_list)
                return;

        mutex_lock(&lock);
        hlist_del(&id_priv->node);
        if (hlist_empty(&bind_list->owners)) {
                cma_ps_remove(net, bind_list->ps, bind_list->port);
                kfree(bind_list);
        }
        mutex_unlock(&lock);
}

static void cma_leave_mc_groups(struct rdma_id_private *id_priv)
{
        struct cma_multicast *mc;

        while (!list_empty(&id_priv->mc_list)) {
                mc = container_of(id_priv->mc_list.next,
                                  struct cma_multicast, list);
                list_del(&mc->list);
                if (rdma_cap_ib_mcast(id_priv->cma_dev->device,
                                      id_priv->id.port_num)) {
                        ib_sa_free_multicast(mc->multicast.ib);
                        kfree(mc);
                } else {
                        if (mc->igmp_joined) {
                                struct rdma_dev_addr *dev_addr =
                                        &id_priv->id.route.addr.dev_addr;
                                struct net_device *ndev = NULL;

                                if (dev_addr->bound_dev_if)
                                        ndev = dev_get_by_index(&init_net,
                                                                dev_addr->bound_dev_if);
                                if (ndev) {
                                        cma_igmp_send(ndev,
                                                      &mc->multicast.ib->rec.mgid,
                                                      false);
                                        dev_put(ndev);
                                }
                        }
                        kref_put(&mc->mcref, release_mc);
                }
        }
}

void rdma_destroy_id(struct rdma_cm_id *id)
{
        struct rdma_id_private *id_priv;
        enum rdma_cm_state state;

        id_priv = container_of(id, struct rdma_id_private, id);
        state = cma_exch(id_priv, RDMA_CM_DESTROYING);
        cma_cancel_operation(id_priv, state);

        /*
         * Wait for any active callback to finish.  New callbacks will find
         * the id_priv state set to destroying and abort.
         */
        mutex_lock(&id_priv->handler_mutex);
        mutex_unlock(&id_priv->handler_mutex);

        if (id_priv->cma_dev) {
                rdma_restrack_del(&id_priv->res);
                if (rdma_cap_ib_cm(id_priv->id.device, 1)) {
                        if (id_priv->cm_id.ib)
                                ib_destroy_cm_id(id_priv->cm_id.ib);
                } else if (rdma_cap_iw_cm(id_priv->id.device, 1)) {
                        if (id_priv->cm_id.iw)
                                iw_destroy_cm_id(id_priv->cm_id.iw);
                }
                cma_leave_mc_groups(id_priv);
                cma_release_dev(id_priv);
        }

        cma_release_port(id_priv);
        cma_deref_id(id_priv);
        wait_for_completion(&id_priv->comp);

        if (id_priv->internal_id)
                cma_deref_id(id_priv->id.context);

        kfree(id_priv->id.route.path_rec);
        put_net(id_priv->id.route.addr.dev_addr.net);
        kfree(id_priv);
}
EXPORT_SYMBOL(rdma_destroy_id);

static int cma_rep_recv(struct rdma_id_private *id_priv)
{
        int ret;

        ret = cma_modify_qp_rtr(id_priv, NULL);
        if (ret)
                goto reject;

        ret = cma_modify_qp_rts(id_priv, NULL);
        if (ret)
                goto reject;

        ret = ib_send_cm_rtu(id_priv->cm_id.ib, NULL, 0);
        if (ret)
                goto reject;

        return 0;
reject:
        pr_debug_ratelimited("RDMA CM: CONNECT_ERROR: failed to handle reply. status %d\n", ret);
        cma_modify_qp_err(id_priv);
        ib_send_cm_rej(id_priv->cm_id.ib, IB_CM_REJ_CONSUMER_DEFINED,
                       NULL, 0, NULL, 0);
        return ret;
}

static void cma_set_rep_event_data(struct rdma_cm_event *event,
                                   struct ib_cm_rep_event_param *rep_data,
                                   void *private_data)
{
        event->param.conn.private_data = private_data;
        event->param.conn.private_data_len = IB_CM_REP_PRIVATE_DATA_SIZE;
        event->param.conn.responder_resources = rep_data->responder_resources;
        event->param.conn.initiator_depth = rep_data->initiator_depth;
        event->param.conn.flow_control = rep_data->flow_control;
        event->param.conn.rnr_retry_count = rep_data->rnr_retry_count;
        event->param.conn.srq = rep_data->srq;
        event->param.conn.qp_num = rep_data->remote_qpn;
}

static int cma_ib_handler(struct ib_cm_id *cm_id, struct ib_cm_event *ib_event)
{
        struct rdma_id_private *id_priv = cm_id->context;
        struct rdma_cm_event event;
        int ret = 0;

        mutex_lock(&id_priv->handler_mutex);
        if ((ib_event->event != IB_CM_TIMEWAIT_EXIT &&
             id_priv->state != RDMA_CM_CONNECT) ||
            (ib_event->event == IB_CM_TIMEWAIT_EXIT &&
             id_priv->state != RDMA_CM_DISCONNECT))
                goto out;

        memset(&event, 0, sizeof event);
        switch (ib_event->event) {
        case IB_CM_REQ_ERROR:
        case IB_CM_REP_ERROR:
                event.event = RDMA_CM_EVENT_UNREACHABLE;
                event.status = -ETIMEDOUT;
                break;
        case IB_CM_REP_RECEIVED:
                if (cma_comp(id_priv, RDMA_CM_CONNECT) &&
                    (id_priv->id.qp_type != IB_QPT_UD))
                        ib_send_cm_mra(cm_id, CMA_CM_MRA_SETTING, NULL, 0);
                if (id_priv->id.qp) {
                        event.status = cma_rep_recv(id_priv);
                        event.event = event.status ? RDMA_CM_EVENT_CONNECT_ERROR :
                                                     RDMA_CM_EVENT_ESTABLISHED;
                } else {
                        event.event = RDMA_CM_EVENT_CONNECT_RESPONSE;
                }
                cma_set_rep_event_data(&event, &ib_event->param.rep_rcvd,
                                       ib_event->private_data);
                break;
        case IB_CM_RTU_RECEIVED:
        case IB_CM_USER_ESTABLISHED:
                event.event = RDMA_CM_EVENT_ESTABLISHED;
                break;
        case IB_CM_DREQ_ERROR:
                event.status = -ETIMEDOUT; /* fall through */
        case IB_CM_DREQ_RECEIVED:
        case IB_CM_DREP_RECEIVED:
                if (!cma_comp_exch(id_priv, RDMA_CM_CONNECT,
                                   RDMA_CM_DISCONNECT))
                        goto out;
                event.event = RDMA_CM_EVENT_DISCONNECTED;
                break;
        case IB_CM_TIMEWAIT_EXIT:
                event.event = RDMA_CM_EVENT_TIMEWAIT_EXIT;
                break;
        case IB_CM_MRA_RECEIVED:
                /* ignore event */
                goto out;
        case IB_CM_REJ_RECEIVED:
                pr_debug_ratelimited("RDMA CM: REJECTED: %s\n", rdma_reject_msg(&id_priv->id,
                                                                                ib_event->param.rej_rcvd.reason));
                cma_modify_qp_err(id_priv);
                event.status = ib_event->param.rej_rcvd.reason;
                event.event = RDMA_CM_EVENT_REJECTED;
                event.param.conn.private_data = ib_event->private_data;
                event.param.conn.private_data_len = IB_CM_REJ_PRIVATE_DATA_SIZE;
                break;
        default:
                pr_err("RDMA CMA: unexpected IB CM event: %d\n",
                       ib_event->event);
                goto out;
        }

        ret = id_priv->id.event_handler(&id_priv->id, &event);
        if (ret) {
                /* Destroy the CM ID by returning a non-zero value. */
                id_priv->cm_id.ib = NULL;
                cma_exch(id_priv, RDMA_CM_DESTROYING);
                mutex_unlock(&id_priv->handler_mutex);
                rdma_destroy_id(&id_priv->id);
                return ret;
        }
out:
        mutex_unlock(&id_priv->handler_mutex);
        return ret;
}

static struct rdma_id_private *cma_new_conn_id(struct rdma_cm_id *listen_id,
                                               struct ib_cm_event *ib_event,
                                               struct net_device *net_dev)
{
        struct rdma_id_private *listen_id_priv;
        struct rdma_id_private *id_priv;
        struct rdma_cm_id *id;
        struct rdma_route *rt;
        const sa_family_t ss_family = listen_id->route.addr.src_addr.ss_family;
        struct sa_path_rec *path = ib_event->param.req_rcvd.primary_path;
        const __be64 service_id =
                ib_event->param.req_rcvd.primary_path->service_id;
        int ret;

        listen_id_priv = container_of(listen_id, struct rdma_id_private, id);
        id = __rdma_create_id(listen_id->route.addr.dev_addr.net,
                            listen_id->event_handler, listen_id->context,
                            listen_id->ps, ib_event->param.req_rcvd.qp_type,
                            listen_id_priv->res.kern_name);
        if (IS_ERR(id))
                return NULL;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (cma_save_net_info((struct sockaddr *)&id->route.addr.src_addr,
                              (struct sockaddr *)&id->route.addr.dst_addr,
                              listen_id, ib_event, ss_family, service_id))
                goto err;

        rt = &id->route;
        rt->num_paths = ib_event->param.req_rcvd.alternate_path ? 2 : 1;
        rt->path_rec = kmalloc(sizeof *rt->path_rec * rt->num_paths,
                               GFP_KERNEL);
        if (!rt->path_rec)
                goto err;

        rt->path_rec[0] = *path;
        if (rt->num_paths == 2)
                rt->path_rec[1] = *ib_event->param.req_rcvd.alternate_path;

        if (net_dev) {
                rdma_copy_addr(&rt->addr.dev_addr, net_dev, NULL);
        } else {
                if (!cma_protocol_roce(listen_id) &&
                    cma_any_addr(cma_src_addr(id_priv))) {
                        rt->addr.dev_addr.dev_type = ARPHRD_INFINIBAND;
                        rdma_addr_set_sgid(&rt->addr.dev_addr, &rt->path_rec[0].sgid);
                        ib_addr_set_pkey(&rt->addr.dev_addr, be16_to_cpu(rt->path_rec[0].pkey));
                } else if (!cma_any_addr(cma_src_addr(id_priv))) {
                        ret = cma_translate_addr(cma_src_addr(id_priv), &rt->addr.dev_addr);
                        if (ret)
                                goto err;
                }
        }
        rdma_addr_set_dgid(&rt->addr.dev_addr, &rt->path_rec[0].dgid);

        id_priv->state = RDMA_CM_CONNECT;
        return id_priv;

err:
        rdma_destroy_id(id);
        return NULL;
}

static struct rdma_id_private *cma_new_udp_id(struct rdma_cm_id *listen_id,
                                              struct ib_cm_event *ib_event,
                                              struct net_device *net_dev)
{
        struct rdma_id_private *listen_id_priv;
        struct rdma_id_private *id_priv;
        struct rdma_cm_id *id;
        const sa_family_t ss_family = listen_id->route.addr.src_addr.ss_family;
        struct net *net = listen_id->route.addr.dev_addr.net;
        int ret;

        listen_id_priv = container_of(listen_id, struct rdma_id_private, id);
        id = __rdma_create_id(net, listen_id->event_handler, listen_id->context,
                              listen_id->ps, IB_QPT_UD,
                              listen_id_priv->res.kern_name);
        if (IS_ERR(id))
                return NULL;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (cma_save_net_info((struct sockaddr *)&id->route.addr.src_addr,
                              (struct sockaddr *)&id->route.addr.dst_addr,
                              listen_id, ib_event, ss_family,
                              ib_event->param.sidr_req_rcvd.service_id))
                goto err;

        if (net_dev) {
                rdma_copy_addr(&id->route.addr.dev_addr, net_dev, NULL);
        } else {
                if (!cma_any_addr(cma_src_addr(id_priv))) {
                        ret = cma_translate_addr(cma_src_addr(id_priv),
                                                 &id->route.addr.dev_addr);
                        if (ret)
                                goto err;
                }
        }

        id_priv->state = RDMA_CM_CONNECT;
        return id_priv;
err:
        rdma_destroy_id(id);
        return NULL;
}

static void cma_set_req_event_data(struct rdma_cm_event *event,
                                   struct ib_cm_req_event_param *req_data,
                                   void *private_data, int offset)
{
        event->param.conn.private_data = private_data + offset;
        event->param.conn.private_data_len = IB_CM_REQ_PRIVATE_DATA_SIZE - offset;
        event->param.conn.responder_resources = req_data->responder_resources;
        event->param.conn.initiator_depth = req_data->initiator_depth;
        event->param.conn.flow_control = req_data->flow_control;
        event->param.conn.retry_count = req_data->retry_count;
        event->param.conn.rnr_retry_count = req_data->rnr_retry_count;
        event->param.conn.srq = req_data->srq;
        event->param.conn.qp_num = req_data->remote_qpn;
}

static int cma_check_req_qp_type(struct rdma_cm_id *id, struct ib_cm_event *ib_event)
{
        return (((ib_event->event == IB_CM_REQ_RECEIVED) &&
                 (ib_event->param.req_rcvd.qp_type == id->qp_type)) ||
                ((ib_event->event == IB_CM_SIDR_REQ_RECEIVED) &&
                 (id->qp_type == IB_QPT_UD)) ||
                (!id->qp_type));
}

static int cma_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *ib_event)
{
        struct rdma_id_private *listen_id, *conn_id = NULL;
        struct rdma_cm_event event;
        struct net_device *net_dev;
        u8 offset;
        int ret;

        listen_id = cma_id_from_event(cm_id, ib_event, &net_dev);
        if (IS_ERR(listen_id))
                return PTR_ERR(listen_id);

        if (!cma_check_req_qp_type(&listen_id->id, ib_event)) {
                ret = -EINVAL;
                goto net_dev_put;
        }

        mutex_lock(&listen_id->handler_mutex);
        if (listen_id->state != RDMA_CM_LISTEN) {
                ret = -ECONNABORTED;
                goto err1;
        }

        memset(&event, 0, sizeof event);
        offset = cma_user_data_offset(listen_id);
        event.event = RDMA_CM_EVENT_CONNECT_REQUEST;
        if (ib_event->event == IB_CM_SIDR_REQ_RECEIVED) {
                conn_id = cma_new_udp_id(&listen_id->id, ib_event, net_dev);
                event.param.ud.private_data = ib_event->private_data + offset;
                event.param.ud.private_data_len =
                                IB_CM_SIDR_REQ_PRIVATE_DATA_SIZE - offset;
        } else {
                conn_id = cma_new_conn_id(&listen_id->id, ib_event, net_dev);
                cma_set_req_event_data(&event, &ib_event->param.req_rcvd,
                                       ib_event->private_data, offset);
        }
        if (!conn_id) {
                ret = -ENOMEM;
                goto err1;
        }

        mutex_lock_nested(&conn_id->handler_mutex, SINGLE_DEPTH_NESTING);
        ret = cma_acquire_dev(conn_id, listen_id);
        if (ret)
                goto err2;

        conn_id->cm_id.ib = cm_id;
        cm_id->context = conn_id;
        cm_id->cm_handler = cma_ib_handler;

        /*
         * Protect against the user destroying conn_id from another thread
         * until we're done accessing it.
         */
        atomic_inc(&conn_id->refcount);
        ret = conn_id->id.event_handler(&conn_id->id, &event);
        if (ret)
                goto err3;
        /*
         * Acquire mutex to prevent user executing rdma_destroy_id()
         * while we're accessing the cm_id.
         */
        mutex_lock(&lock);
        if (cma_comp(conn_id, RDMA_CM_CONNECT) &&
            (conn_id->id.qp_type != IB_QPT_UD))
                ib_send_cm_mra(cm_id, CMA_CM_MRA_SETTING, NULL, 0);
        mutex_unlock(&lock);
        mutex_unlock(&conn_id->handler_mutex);
        mutex_unlock(&listen_id->handler_mutex);
        cma_deref_id(conn_id);

        if (net_dev)
                dev_put(net_dev);
        return 0;

err3:
        cma_deref_id(conn_id);
        /* Destroy the CM ID by returning a non-zero value. */
        conn_id->cm_id.ib = NULL;
err2:
        cma_exch(conn_id, RDMA_CM_DESTROYING);
        mutex_unlock(&conn_id->handler_mutex);
err1:
        mutex_unlock(&listen_id->handler_mutex);
        if (conn_id)
                rdma_destroy_id(&conn_id->id);

net_dev_put:
        if (net_dev)
                dev_put(net_dev);

        return ret;
}

__be64 rdma_get_service_id(struct rdma_cm_id *id, struct sockaddr *addr)
{
        if (addr->sa_family == AF_IB)
                return ((struct sockaddr_ib *) addr)->sib_sid;

        return cpu_to_be64(((u64)id->ps << 16) + be16_to_cpu(cma_port(addr)));
}
EXPORT_SYMBOL(rdma_get_service_id);

void rdma_read_gids(struct rdma_cm_id *cm_id, union ib_gid *sgid,
                    union ib_gid *dgid)
{
        struct rdma_addr *addr = &cm_id->route.addr;

        if (!cm_id->device) {
                if (sgid)
                        memset(sgid, 0, sizeof(*sgid));
                if (dgid)
                        memset(dgid, 0, sizeof(*dgid));
                return;
        }

        if (rdma_protocol_roce(cm_id->device, cm_id->port_num)) {
                if (sgid)
                        rdma_ip2gid((struct sockaddr *)&addr->src_addr, sgid);
                if (dgid)
                        rdma_ip2gid((struct sockaddr *)&addr->dst_addr, dgid);
        } else {
                if (sgid)
                        rdma_addr_get_sgid(&addr->dev_addr, sgid);
                if (dgid)
                        rdma_addr_get_dgid(&addr->dev_addr, dgid);
        }
}
EXPORT_SYMBOL(rdma_read_gids);

static int cma_iw_handler(struct iw_cm_id *iw_id, struct iw_cm_event *iw_event)
{
        struct rdma_id_private *id_priv = iw_id->context;
        struct rdma_cm_event event;
        int ret = 0;
        struct sockaddr *laddr = (struct sockaddr *)&iw_event->local_addr;
        struct sockaddr *raddr = (struct sockaddr *)&iw_event->remote_addr;

        mutex_lock(&id_priv->handler_mutex);
        if (id_priv->state != RDMA_CM_CONNECT)
                goto out;

        memset(&event, 0, sizeof event);
        switch (iw_event->event) {
        case IW_CM_EVENT_CLOSE:
                event.event = RDMA_CM_EVENT_DISCONNECTED;
                break;
        case IW_CM_EVENT_CONNECT_REPLY:
                memcpy(cma_src_addr(id_priv), laddr,
                       rdma_addr_size(laddr));
                memcpy(cma_dst_addr(id_priv), raddr,
                       rdma_addr_size(raddr));
                switch (iw_event->status) {
                case 0:
                        event.event = RDMA_CM_EVENT_ESTABLISHED;
                        event.param.conn.initiator_depth = iw_event->ird;
                        event.param.conn.responder_resources = iw_event->ord;
                        break;
                case -ECONNRESET:
                case -ECONNREFUSED:
                        event.event = RDMA_CM_EVENT_REJECTED;
                        break;
                case -ETIMEDOUT:
                        event.event = RDMA_CM_EVENT_UNREACHABLE;
                        break;
                default:
                        event.event = RDMA_CM_EVENT_CONNECT_ERROR;
                        break;
                }
                break;
        case IW_CM_EVENT_ESTABLISHED:
                event.event = RDMA_CM_EVENT_ESTABLISHED;
                event.param.conn.initiator_depth = iw_event->ird;
                event.param.conn.responder_resources = iw_event->ord;
                break;
        default:
                BUG_ON(1);
        }

        event.status = iw_event->status;
        event.param.conn.private_data = iw_event->private_data;
        event.param.conn.private_data_len = iw_event->private_data_len;
        ret = id_priv->id.event_handler(&id_priv->id, &event);
        if (ret) {
                /* Destroy the CM ID by returning a non-zero value. */
                id_priv->cm_id.iw = NULL;
                cma_exch(id_priv, RDMA_CM_DESTROYING);
                mutex_unlock(&id_priv->handler_mutex);
                rdma_destroy_id(&id_priv->id);
                return ret;
        }

out:
        mutex_unlock(&id_priv->handler_mutex);
        return ret;
}

static int iw_conn_req_handler(struct iw_cm_id *cm_id,
                               struct iw_cm_event *iw_event)
{
        struct rdma_cm_id *new_cm_id;
        struct rdma_id_private *listen_id, *conn_id;
        struct rdma_cm_event event;
        int ret = -ECONNABORTED;
        struct sockaddr *laddr = (struct sockaddr *)&iw_event->local_addr;
        struct sockaddr *raddr = (struct sockaddr *)&iw_event->remote_addr;

        listen_id = cm_id->context;

        mutex_lock(&listen_id->handler_mutex);
        if (listen_id->state != RDMA_CM_LISTEN)
                goto out;

        /* Create a new RDMA id for the new IW CM ID */
        new_cm_id = __rdma_create_id(listen_id->id.route.addr.dev_addr.net,
                                     listen_id->id.event_handler,
                                     listen_id->id.context,
                                     RDMA_PS_TCP, IB_QPT_RC,
                                     listen_id->res.kern_name);
        if (IS_ERR(new_cm_id)) {
                ret = -ENOMEM;
                goto out;
        }
        conn_id = container_of(new_cm_id, struct rdma_id_private, id);
        mutex_lock_nested(&conn_id->handler_mutex, SINGLE_DEPTH_NESTING);
        conn_id->state = RDMA_CM_CONNECT;

        ret = rdma_translate_ip(laddr, &conn_id->id.route.addr.dev_addr);
        if (ret) {
                mutex_unlock(&conn_id->handler_mutex);
                rdma_destroy_id(new_cm_id);
                goto out;
        }

        ret = cma_acquire_dev(conn_id, listen_id);
        if (ret) {
                mutex_unlock(&conn_id->handler_mutex);
                rdma_destroy_id(new_cm_id);
                goto out;
        }

        conn_id->cm_id.iw = cm_id;
        cm_id->context = conn_id;
        cm_id->cm_handler = cma_iw_handler;

        memcpy(cma_src_addr(conn_id), laddr, rdma_addr_size(laddr));
        memcpy(cma_dst_addr(conn_id), raddr, rdma_addr_size(raddr));

        memset(&event, 0, sizeof event);
        event.event = RDMA_CM_EVENT_CONNECT_REQUEST;
        event.param.conn.private_data = iw_event->private_data;
        event.param.conn.private_data_len = iw_event->private_data_len;
        event.param.conn.initiator_depth = iw_event->ird;
        event.param.conn.responder_resources = iw_event->ord;

        /*
         * Protect against the user destroying conn_id from another thread
         * until we're done accessing it.
         */
        atomic_inc(&conn_id->refcount);
        ret = conn_id->id.event_handler(&conn_id->id, &event);
        if (ret) {
                /* User wants to destroy the CM ID */
                conn_id->cm_id.iw = NULL;
                cma_exch(conn_id, RDMA_CM_DESTROYING);
                mutex_unlock(&conn_id->handler_mutex);
                cma_deref_id(conn_id);
                rdma_destroy_id(&conn_id->id);
                goto out;
        }

        mutex_unlock(&conn_id->handler_mutex);
        cma_deref_id(conn_id);

out:
        mutex_unlock(&listen_id->handler_mutex);
        return ret;
}

static int cma_ib_listen(struct rdma_id_private *id_priv)
{
        struct sockaddr *addr;
        struct ib_cm_id *id;
        __be64 svc_id;

        addr = cma_src_addr(id_priv);
        svc_id = rdma_get_service_id(&id_priv->id, addr);
        id = ib_cm_insert_listen(id_priv->id.device, cma_req_handler, svc_id);
        if (IS_ERR(id))
                return PTR_ERR(id);
        id_priv->cm_id.ib = id;

        return 0;
}

static int cma_iw_listen(struct rdma_id_private *id_priv, int backlog)
{
        int ret;
        struct iw_cm_id *id;

        id = iw_create_cm_id(id_priv->id.device,
                             iw_conn_req_handler,
                             id_priv);
        if (IS_ERR(id))
                return PTR_ERR(id);

        id->tos = id_priv->tos;
        id_priv->cm_id.iw = id;

        memcpy(&id_priv->cm_id.iw->local_addr, cma_src_addr(id_priv),
               rdma_addr_size(cma_src_addr(id_priv)));

        ret = iw_cm_listen(id_priv->cm_id.iw, backlog);

        if (ret) {
                iw_destroy_cm_id(id_priv->cm_id.iw);
                id_priv->cm_id.iw = NULL;
        }

        return ret;
}

static int cma_listen_handler(struct rdma_cm_id *id,
                              struct rdma_cm_event *event)
{
        struct rdma_id_private *id_priv = id->context;

        id->context = id_priv->id.context;
        id->event_handler = id_priv->id.event_handler;
        return id_priv->id.event_handler(id, event);
}

static void cma_listen_on_dev(struct rdma_id_private *id_priv,
                              struct cma_device *cma_dev)
{
        struct rdma_id_private *dev_id_priv;
        struct rdma_cm_id *id;
        struct net *net = id_priv->id.route.addr.dev_addr.net;
        int ret;

        if (cma_family(id_priv) == AF_IB && !rdma_cap_ib_cm(cma_dev->device, 1))
                return;

        id = __rdma_create_id(net, cma_listen_handler, id_priv, id_priv->id.ps,
                              id_priv->id.qp_type, id_priv->res.kern_name);
        if (IS_ERR(id))
                return;

        dev_id_priv = container_of(id, struct rdma_id_private, id);

        dev_id_priv->state = RDMA_CM_ADDR_BOUND;
        memcpy(cma_src_addr(dev_id_priv), cma_src_addr(id_priv),
               rdma_addr_size(cma_src_addr(id_priv)));

        _cma_attach_to_dev(dev_id_priv, cma_dev);
        list_add_tail(&dev_id_priv->listen_list, &id_priv->listen_list);
        atomic_inc(&id_priv->refcount);
        dev_id_priv->internal_id = 1;
        dev_id_priv->afonly = id_priv->afonly;

        ret = rdma_listen(id, id_priv->backlog);
        if (ret)
                pr_warn("RDMA CMA: cma_listen_on_dev, error %d, listening on device %s\n",
                        ret, cma_dev->device->name);
}

static void cma_listen_on_all(struct rdma_id_private *id_priv)
{
        struct cma_device *cma_dev;

        mutex_lock(&lock);
        list_add_tail(&id_priv->list, &listen_any_list);
        list_for_each_entry(cma_dev, &dev_list, list)
                cma_listen_on_dev(id_priv, cma_dev);
        mutex_unlock(&lock);
}

void rdma_set_service_type(struct rdma_cm_id *id, int tos)
{
        struct rdma_id_private *id_priv;

        id_priv = container_of(id, struct rdma_id_private, id);
        id_priv->tos = (u8) tos;
        id_priv->tos_set = true;
}
EXPORT_SYMBOL(rdma_set_service_type);

static void cma_query_handler(int status, struct sa_path_rec *path_rec,
                              void *context)
{
        struct cma_work *work = context;
        struct rdma_route *route;

        route = &work->id->id.route;

        if (!status) {
                route->num_paths = 1;
                *route->path_rec = *path_rec;
        } else {
                work->old_state = RDMA_CM_ROUTE_QUERY;
                work->new_state = RDMA_CM_ADDR_RESOLVED;
                work->event.event = RDMA_CM_EVENT_ROUTE_ERROR;
                work->event.status = status;
                pr_debug_ratelimited("RDMA CM: ROUTE_ERROR: failed to query path. status %d\n",
                                     status);
        }

        queue_work(cma_wq, &work->work);
}

static int cma_query_ib_route(struct rdma_id_private *id_priv, int timeout_ms,
                              struct cma_work *work)
{
        struct rdma_dev_addr *dev_addr = &id_priv->id.route.addr.dev_addr;
        struct sa_path_rec path_rec;
        ib_sa_comp_mask comp_mask;
        struct sockaddr_in6 *sin6;
        struct sockaddr_ib *sib;

        memset(&path_rec, 0, sizeof path_rec);

        if (rdma_cap_opa_ah(id_priv->id.device, id_priv->id.port_num))
                path_rec.rec_type = SA_PATH_REC_TYPE_OPA;
        else
                path_rec.rec_type = SA_PATH_REC_TYPE_IB;
        rdma_addr_get_sgid(dev_addr, &path_rec.sgid);
        rdma_addr_get_dgid(dev_addr, &path_rec.dgid);
        path_rec.pkey = cpu_to_be16(ib_addr_get_pkey(dev_addr));
        path_rec.numb_path = 1;
        path_rec.reversible = 1;
        path_rec.service_id = rdma_get_service_id(&id_priv->id,
                                                  cma_dst_addr(id_priv));

        comp_mask = IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID |
                    IB_SA_PATH_REC_PKEY | IB_SA_PATH_REC_NUMB_PATH |
                    IB_SA_PATH_REC_REVERSIBLE | IB_SA_PATH_REC_SERVICE_ID;

        switch (cma_family(id_priv)) {
        case AF_INET:
                path_rec.qos_class = cpu_to_be16((u16) id_priv->tos);
                comp_mask |= IB_SA_PATH_REC_QOS_CLASS;
                break;
        case AF_INET6:
                sin6 = (struct sockaddr_in6 *) cma_src_addr(id_priv);
                path_rec.traffic_class = (u8) (be32_to_cpu(sin6->sin6_flowinfo) >> 20);
                comp_mask |= IB_SA_PATH_REC_TRAFFIC_CLASS;
                break;
        case AF_IB:
                sib = (struct sockaddr_ib *) cma_src_addr(id_priv);
                path_rec.traffic_class = (u8) (be32_to_cpu(sib->sib_flowinfo) >> 20);
                comp_mask |= IB_SA_PATH_REC_TRAFFIC_CLASS;
                break;
        }

        id_priv->query_id = ib_sa_path_rec_get(&sa_client, id_priv->id.device,
                                               id_priv->id.port_num, &path_rec,
                                               comp_mask, timeout_ms,
                                               GFP_KERNEL, cma_query_handler,
                                               work, &id_priv->query);

        return (id_priv->query_id < 0) ? id_priv->query_id : 0;
}

static void cma_work_handler(struct work_struct *_work)
{
        struct cma_work *work = container_of(_work, struct cma_work, work);
        struct rdma_id_private *id_priv = work->id;
        int destroy = 0;

        mutex_lock(&id_priv->handler_mutex);
        if (!cma_comp_exch(id_priv, work->old_state, work->new_state))
                goto out;

        if (id_priv->id.event_handler(&id_priv->id, &work->event)) {
                cma_exch(id_priv, RDMA_CM_DESTROYING);
                destroy = 1;
        }
out:
        mutex_unlock(&id_priv->handler_mutex);
        cma_deref_id(id_priv);
        if (destroy)
                rdma_destroy_id(&id_priv->id);
        kfree(work);
}

static void cma_ndev_work_handler(struct work_struct *_work)
{
        struct cma_ndev_work *work = container_of(_work, struct cma_ndev_work, work);
        struct rdma_id_private *id_priv = work->id;
        int destroy = 0;

        mutex_lock(&id_priv->handler_mutex);
        if (id_priv->state == RDMA_CM_DESTROYING ||
            id_priv->state == RDMA_CM_DEVICE_REMOVAL)
                goto out;

        if (id_priv->id.event_handler(&id_priv->id, &work->event)) {
                cma_exch(id_priv, RDMA_CM_DESTROYING);
                destroy = 1;
        }

out:
        mutex_unlock(&id_priv->handler_mutex);
        cma_deref_id(id_priv);
        if (destroy)
                rdma_destroy_id(&id_priv->id);
        kfree(work);
}

static void cma_init_resolve_route_work(struct cma_work *work,
                                        struct rdma_id_private *id_priv)
{
        work->id = id_priv;
        INIT_WORK(&work->work, cma_work_handler);
        work->old_state = RDMA_CM_ROUTE_QUERY;
        work->new_state = RDMA_CM_ROUTE_RESOLVED;
        work->event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
}

static void cma_init_resolve_addr_work(struct cma_work *work,
                                       struct rdma_id_private *id_priv)
{
        work->id = id_priv;
        INIT_WORK(&work->work, cma_work_handler);
        work->old_state = RDMA_CM_ADDR_QUERY;
        work->new_state = RDMA_CM_ADDR_RESOLVED;
        work->event.event = RDMA_CM_EVENT_ADDR_RESOLVED;
}

static int cma_resolve_ib_route(struct rdma_id_private *id_priv, int timeout_ms)
{
        struct rdma_route *route = &id_priv->id.route;
        struct cma_work *work;
        int ret;

        work = kzalloc(sizeof *work, GFP_KERNEL);
        if (!work)
                return -ENOMEM;

        cma_init_resolve_route_work(work, id_priv);

        route->path_rec = kmalloc(sizeof *route->path_rec, GFP_KERNEL);
        if (!route->path_rec) {
                ret = -ENOMEM;
                goto err1;
        }

        ret = cma_query_ib_route(id_priv, timeout_ms, work);
        if (ret)
                goto err2;

        return 0;
err2:
        kfree(route->path_rec);
        route->path_rec = NULL;
err1:
        kfree(work);
        return ret;
}

static enum ib_gid_type cma_route_gid_type(enum rdma_network_type network_type,
                                           unsigned long supported_gids,
                                           enum ib_gid_type default_gid)
{
        if ((network_type == RDMA_NETWORK_IPV4 ||
             network_type == RDMA_NETWORK_IPV6) &&
            test_bit(IB_GID_TYPE_ROCE_UDP_ENCAP, &supported_gids))
                return IB_GID_TYPE_ROCE_UDP_ENCAP;

        return default_gid;
}

/*
 * cma_iboe_set_path_rec_l2_fields() is helper function which sets
 * path record type based on GID type.
 * It also sets up other L2 fields which includes destination mac address
 * netdev ifindex, of the path record.
 * It returns the netdev of the bound interface for this path record entry.
 */
static struct net_device *
cma_iboe_set_path_rec_l2_fields(struct rdma_id_private *id_priv)
{
        struct rdma_route *route = &id_priv->id.route;
        enum ib_gid_type gid_type = IB_GID_TYPE_ROCE;
        struct rdma_addr *addr = &route->addr;
        unsigned long supported_gids;
        struct net_device *ndev;

        if (!addr->dev_addr.bound_dev_if)
                return NULL;

        ndev = dev_get_by_index(addr->dev_addr.net,
                                addr->dev_addr.bound_dev_if);
        if (!ndev)
                return NULL;

        supported_gids = roce_gid_type_mask_support(id_priv->id.device,
                                                    id_priv->id.port_num);
        gid_type = cma_route_gid_type(addr->dev_addr.network,
                                      supported_gids,
                                      id_priv->gid_type);
        /* Use the hint from IP Stack to select GID Type */
        if (gid_type < ib_network_to_gid_type(addr->dev_addr.network))
                gid_type = ib_network_to_gid_type(addr->dev_addr.network);
        route->path_rec->rec_type = sa_conv_gid_to_pathrec_type(gid_type);

        route->path_rec->roce.route_resolved = true;
        sa_path_set_ndev(route->path_rec, addr->dev_addr.net);
        sa_path_set_ifindex(route->path_rec, ndev->ifindex);
        sa_path_set_dmac(route->path_rec, addr->dev_addr.dst_dev_addr);
        return ndev;
}

int rdma_set_ib_path(struct rdma_cm_id *id,
                     struct sa_path_rec *path_rec)
{
        struct rdma_id_private *id_priv;
        struct net_device *ndev;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_RESOLVED,
                           RDMA_CM_ROUTE_RESOLVED))
                return -EINVAL;

        id->route.path_rec = kmemdup(path_rec, sizeof(*path_rec),
                                     GFP_KERNEL);
        if (!id->route.path_rec) {
                ret = -ENOMEM;
                goto err;
        }

        if (rdma_protocol_roce(id->device, id->port_num)) {
                ndev = cma_iboe_set_path_rec_l2_fields(id_priv);
                if (!ndev) {
                        ret = -ENODEV;
                        goto err_free;
                }
                dev_put(ndev);
        }

        id->route.num_paths = 1;
        return 0;

err_free:
        kfree(id->route.path_rec);
        id->route.path_rec = NULL;
err:
        cma_comp_exch(id_priv, RDMA_CM_ROUTE_RESOLVED, RDMA_CM_ADDR_RESOLVED);
        return ret;
}
EXPORT_SYMBOL(rdma_set_ib_path);

static int cma_resolve_iw_route(struct rdma_id_private *id_priv, int timeout_ms)
{
        struct cma_work *work;

        work = kzalloc(sizeof *work, GFP_KERNEL);
        if (!work)
                return -ENOMEM;

        cma_init_resolve_route_work(work, id_priv);
        queue_work(cma_wq, &work->work);
        return 0;
}

static int iboe_tos_to_sl(struct net_device *ndev, int tos)
{
        int prio;
        struct net_device *dev;

        prio = rt_tos2priority(tos);
        dev = is_vlan_dev(ndev) ? vlan_dev_real_dev(ndev) : ndev;
        if (dev->num_tc)
                return netdev_get_prio_tc_map(dev, prio);

#if IS_ENABLED(CONFIG_VLAN_8021Q)
        if (is_vlan_dev(ndev))
                return (vlan_dev_get_egress_qos_mask(ndev, prio) &
                        VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
#endif
        return 0;
}

static int cma_resolve_iboe_route(struct rdma_id_private *id_priv)
{
        struct rdma_route *route = &id_priv->id.route;
        struct rdma_addr *addr = &route->addr;
        struct cma_work *work;
        int ret;
        struct net_device *ndev;

        u8 default_roce_tos = id_priv->cma_dev->default_roce_tos[id_priv->id.port_num -
                                        rdma_start_port(id_priv->cma_dev->device)];
        u8 tos = id_priv->tos_set ? id_priv->tos : default_roce_tos;


        work = kzalloc(sizeof *work, GFP_KERNEL);
        if (!work)
                return -ENOMEM;

        route->path_rec = kzalloc(sizeof *route->path_rec, GFP_KERNEL);
        if (!route->path_rec) {
                ret = -ENOMEM;
                goto err1;
        }

        route->num_paths = 1;

        ndev = cma_iboe_set_path_rec_l2_fields(id_priv);
        if (!ndev) {
                ret = -ENODEV;
                goto err2;
        }

        rdma_ip2gid((struct sockaddr *)&id_priv->id.route.addr.src_addr,
                    &route->path_rec->sgid);
        rdma_ip2gid((struct sockaddr *)&id_priv->id.route.addr.dst_addr,
                    &route->path_rec->dgid);

        if (((struct sockaddr *)&id_priv->id.route.addr.dst_addr)->sa_family != AF_IB)
                /* TODO: get the hoplimit from the inet/inet6 device */
                route->path_rec->hop_limit = addr->dev_addr.hoplimit;
        else
                route->path_rec->hop_limit = 1;
        route->path_rec->reversible = 1;
        route->path_rec->pkey = cpu_to_be16(0xffff);
        route->path_rec->mtu_selector = IB_SA_EQ;
        route->path_rec->sl = iboe_tos_to_sl(ndev, tos);
        route->path_rec->traffic_class = tos;
        route->path_rec->mtu = iboe_get_mtu(ndev->mtu);
        route->path_rec->rate_selector = IB_SA_EQ;
        route->path_rec->rate = iboe_get_rate(ndev);
        dev_put(ndev);
        route->path_rec->packet_life_time_selector = IB_SA_EQ;
        route->path_rec->packet_life_time = CMA_IBOE_PACKET_LIFETIME;
        if (!route->path_rec->mtu) {
                ret = -EINVAL;
                goto err2;
        }

        cma_init_resolve_route_work(work, id_priv);
        queue_work(cma_wq, &work->work);

        return 0;

err2:
        kfree(route->path_rec);
        route->path_rec = NULL;
err1:
        kfree(work);
        return ret;
}

int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms)
{
        struct rdma_id_private *id_priv;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_RESOLVED, RDMA_CM_ROUTE_QUERY))
                return -EINVAL;

        atomic_inc(&id_priv->refcount);
        if (rdma_cap_ib_sa(id->device, id->port_num))
                ret = cma_resolve_ib_route(id_priv, timeout_ms);
        else if (rdma_protocol_roce(id->device, id->port_num))
                ret = cma_resolve_iboe_route(id_priv);
        else if (rdma_protocol_iwarp(id->device, id->port_num))
                ret = cma_resolve_iw_route(id_priv, timeout_ms);
        else
                ret = -ENOSYS;

        if (ret)
                goto err;

        return 0;
err:
        cma_comp_exch(id_priv, RDMA_CM_ROUTE_QUERY, RDMA_CM_ADDR_RESOLVED);
        cma_deref_id(id_priv);
        return ret;
}
EXPORT_SYMBOL(rdma_resolve_route);

static void cma_set_loopback(struct sockaddr *addr)
{
        switch (addr->sa_family) {
        case AF_INET:
                ((struct sockaddr_in *) addr)->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
                break;
        case AF_INET6:
                ipv6_addr_set(&((struct sockaddr_in6 *) addr)->sin6_addr,
                              0, 0, 0, htonl(1));
                break;
        default:
                ib_addr_set(&((struct sockaddr_ib *) addr)->sib_addr,
                            0, 0, 0, htonl(1));
                break;
        }
}

static int cma_bind_loopback(struct rdma_id_private *id_priv)
{
        struct cma_device *cma_dev, *cur_dev;
        union ib_gid gid;
        enum ib_port_state port_state;
        u16 pkey;
        int ret;
        u8 p;

        cma_dev = NULL;
        mutex_lock(&lock);
        list_for_each_entry(cur_dev, &dev_list, list) {
                if (cma_family(id_priv) == AF_IB &&
                    !rdma_cap_ib_cm(cur_dev->device, 1))
                        continue;

                if (!cma_dev)
                        cma_dev = cur_dev;

                for (p = 1; p <= cur_dev->device->phys_port_cnt; ++p) {
                        if (!ib_get_cached_port_state(cur_dev->device, p, &port_state) &&
                            port_state == IB_PORT_ACTIVE) {
                                cma_dev = cur_dev;
                                goto port_found;
                        }
                }
        }

        if (!cma_dev) {
                ret = -ENODEV;
                goto out;
        }

        p = 1;

port_found:
        ret = ib_get_cached_gid(cma_dev->device, p, 0, &gid, NULL);
        if (ret)
                goto out;

        ret = ib_get_cached_pkey(cma_dev->device, p, 0, &pkey);
        if (ret)
                goto out;

        id_priv->id.route.addr.dev_addr.dev_type =
                (rdma_protocol_ib(cma_dev->device, p)) ?
                ARPHRD_INFINIBAND : ARPHRD_ETHER;

        rdma_addr_set_sgid(&id_priv->id.route.addr.dev_addr, &gid);
        ib_addr_set_pkey(&id_priv->id.route.addr.dev_addr, pkey);
        id_priv->id.port_num = p;
        cma_attach_to_dev(id_priv, cma_dev);
        cma_set_loopback(cma_src_addr(id_priv));
out:
        mutex_unlock(&lock);
        return ret;
}

static void addr_handler(int status, struct sockaddr *src_addr,
                         struct rdma_dev_addr *dev_addr, void *context)
{
        struct rdma_id_private *id_priv = context;
        struct rdma_cm_event event;

        memset(&event, 0, sizeof event);
        mutex_lock(&id_priv->handler_mutex);
        if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY,
                           RDMA_CM_ADDR_RESOLVED))
                goto out;

        memcpy(cma_src_addr(id_priv), src_addr, rdma_addr_size(src_addr));
        if (!status && !id_priv->cma_dev) {
                status = cma_acquire_dev(id_priv, NULL);
                if (status)
                        pr_debug_ratelimited("RDMA CM: ADDR_ERROR: failed to acquire device. status %d\n",
                                             status);
        } else {
                pr_debug_ratelimited("RDMA CM: ADDR_ERROR: failed to resolve IP. status %d\n", status);
        }

        if (status) {
                if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_RESOLVED,
                                   RDMA_CM_ADDR_BOUND))
                        goto out;
                event.event = RDMA_CM_EVENT_ADDR_ERROR;
                event.status = status;
        } else
                event.event = RDMA_CM_EVENT_ADDR_RESOLVED;

        if (id_priv->id.event_handler(&id_priv->id, &event)) {
                cma_exch(id_priv, RDMA_CM_DESTROYING);
                mutex_unlock(&id_priv->handler_mutex);
                cma_deref_id(id_priv);
                rdma_destroy_id(&id_priv->id);
                return;
        }
out:
        mutex_unlock(&id_priv->handler_mutex);
        cma_deref_id(id_priv);
}

static int cma_resolve_loopback(struct rdma_id_private *id_priv)
{
        struct cma_work *work;
        union ib_gid gid;
        int ret;

        work = kzalloc(sizeof *work, GFP_KERNEL);
        if (!work)
                return -ENOMEM;

        if (!id_priv->cma_dev) {
                ret = cma_bind_loopback(id_priv);
                if (ret)
                        goto err;
        }

        rdma_addr_get_sgid(&id_priv->id.route.addr.dev_addr, &gid);
        rdma_addr_set_dgid(&id_priv->id.route.addr.dev_addr, &gid);

        cma_init_resolve_addr_work(work, id_priv);
        queue_work(cma_wq, &work->work);
        return 0;
err:
        kfree(work);
        return ret;
}

static int cma_resolve_ib_addr(struct rdma_id_private *id_priv)
{
        struct cma_work *work;
        int ret;

        work = kzalloc(sizeof *work, GFP_KERNEL);
        if (!work)
                return -ENOMEM;

        if (!id_priv->cma_dev) {
                ret = cma_resolve_ib_dev(id_priv);
                if (ret)
                        goto err;
        }

        rdma_addr_set_dgid(&id_priv->id.route.addr.dev_addr, (union ib_gid *)
                &(((struct sockaddr_ib *) &id_priv->id.route.addr.dst_addr)->sib_addr));

        cma_init_resolve_addr_work(work, id_priv);
        queue_work(cma_wq, &work->work);
        return 0;
err:
        kfree(work);
        return ret;
}

static int cma_bind_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
                         struct sockaddr *dst_addr)
{
        if (!src_addr || !src_addr->sa_family) {
                src_addr = (struct sockaddr *) &id->route.addr.src_addr;
                src_addr->sa_family = dst_addr->sa_family;
                if (IS_ENABLED(CONFIG_IPV6) &&
                    dst_addr->sa_family == AF_INET6) {
                        struct sockaddr_in6 *src_addr6 = (struct sockaddr_in6 *) src_addr;
                        struct sockaddr_in6 *dst_addr6 = (struct sockaddr_in6 *) dst_addr;
                        src_addr6->sin6_scope_id = dst_addr6->sin6_scope_id;
                        if (ipv6_addr_type(&dst_addr6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
                                id->route.addr.dev_addr.bound_dev_if = dst_addr6->sin6_scope_id;
                } else if (dst_addr->sa_family == AF_IB) {
                        ((struct sockaddr_ib *) src_addr)->sib_pkey =
                                ((struct sockaddr_ib *) dst_addr)->sib_pkey;
                }
        }
        return rdma_bind_addr(id, src_addr);
}

int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
                      struct sockaddr *dst_addr, int timeout_ms)
{
        struct rdma_id_private *id_priv;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        memcpy(cma_dst_addr(id_priv), dst_addr, rdma_addr_size(dst_addr));
        if (id_priv->state == RDMA_CM_IDLE) {
                ret = cma_bind_addr(id, src_addr, dst_addr);
                if (ret) {
                        memset(cma_dst_addr(id_priv), 0, rdma_addr_size(dst_addr));
                        return ret;
                }
        }

        if (cma_family(id_priv) != dst_addr->sa_family) {
                memset(cma_dst_addr(id_priv), 0, rdma_addr_size(dst_addr));
                return -EINVAL;
        }

        if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND, RDMA_CM_ADDR_QUERY)) {
                memset(cma_dst_addr(id_priv), 0, rdma_addr_size(dst_addr));
                return -EINVAL;
        }

        atomic_inc(&id_priv->refcount);
        if (cma_any_addr(dst_addr)) {
                ret = cma_resolve_loopback(id_priv);
        } else {
                if (dst_addr->sa_family == AF_IB) {
                        ret = cma_resolve_ib_addr(id_priv);
                } else {
                        ret = rdma_resolve_ip(&addr_client, cma_src_addr(id_priv),
                                              dst_addr, &id->route.addr.dev_addr,
                                              timeout_ms, addr_handler, id_priv);
                }
        }
        if (ret)
                goto err;

        return 0;
err:
        cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY, RDMA_CM_ADDR_BOUND);
        cma_deref_id(id_priv);
        return ret;
}
EXPORT_SYMBOL(rdma_resolve_addr);

int rdma_set_reuseaddr(struct rdma_cm_id *id, int reuse)
{
        struct rdma_id_private *id_priv;
        unsigned long flags;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        spin_lock_irqsave(&id_priv->lock, flags);
        if (reuse || id_priv->state == RDMA_CM_IDLE) {
                id_priv->reuseaddr = reuse;
                ret = 0;
        } else {
                ret = -EINVAL;
        }
        spin_unlock_irqrestore(&id_priv->lock, flags);
        return ret;
}
EXPORT_SYMBOL(rdma_set_reuseaddr);

int rdma_set_afonly(struct rdma_cm_id *id, int afonly)
{
        struct rdma_id_private *id_priv;
        unsigned long flags;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        spin_lock_irqsave(&id_priv->lock, flags);
        if (id_priv->state == RDMA_CM_IDLE || id_priv->state == RDMA_CM_ADDR_BOUND) {
                id_priv->options |= (1 << CMA_OPTION_AFONLY);
                id_priv->afonly = afonly;
                ret = 0;
        } else {
                ret = -EINVAL;
        }
        spin_unlock_irqrestore(&id_priv->lock, flags);
        return ret;
}
EXPORT_SYMBOL(rdma_set_afonly);

static void cma_bind_port(struct rdma_bind_list *bind_list,
                          struct rdma_id_private *id_priv)
{
        struct sockaddr *addr;
        struct sockaddr_ib *sib;
        u64 sid, mask;
        __be16 port;