/*
 * 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 licensed under one of the following licenses:
 *
 * 1) under the terms of the "Common Public License 1.0" a copy of which is
 *    available from the Open Source Initiative, see
 *    http://www.opensource.org/licenses/cpl.php.
 *
 * 2) under the terms of the "The BSD License" a copy of which is
 *    available from the Open Source Initiative, see
 *    http://www.opensource.org/licenses/bsd-license.php.
 *
 * 3) under the terms of the "GNU General Public License (GPL) Version 2" a
 *    copy of which is available from the Open Source Initiative, see
 *    http://www.opensource.org/licenses/gpl-license.php.
 *
 * Licensee has the right to choose one of the above licenses.
 *
 * Redistributions of source code must retain the above copyright
 * notice and one of the license notices.
 *
 * Redistributions in binary form must reproduce both the above copyright
 * notice, one of the license notices in the documentation
 * and/or other materials provided with the distribution.
 *
 */

#include <linux/completion.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/mutex.h>
#include <linux/random.h>
#include <linux/idr.h>

#include <net/tcp.h>

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

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

#define CMA_CM_RESPONSE_TIMEOUT 20
#define CMA_MAX_CM_RETRIES 15

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

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

static LIST_HEAD(dev_list);
static LIST_HEAD(listen_any_list);
static DEFINE_MUTEX(lock);
static struct workqueue_struct *cma_wq;
static DEFINE_IDR(sdp_ps);
static DEFINE_IDR(tcp_ps);

struct cma_device {
        struct list_head        list;
        struct ib_device        *device;
        __be64                  node_guid;
        struct completion       comp;
        atomic_t                refcount;
        struct list_head        id_list;
};

enum cma_state {
        CMA_IDLE,
        CMA_ADDR_QUERY,
        CMA_ADDR_RESOLVED,
        CMA_ROUTE_QUERY,
        CMA_ROUTE_RESOLVED,
        CMA_CONNECT,
        CMA_DISCONNECT,
        CMA_ADDR_BOUND,
        CMA_LISTEN,
        CMA_DEVICE_REMOVAL,
        CMA_DESTROYING
};

struct rdma_bind_list {
        struct idr              *ps;
        struct hlist_head       owners;
        unsigned short          port;
};

/*
 * 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 rdma_id_private {
        struct rdma_cm_id       id;

        struct rdma_bind_list   *bind_list;
        struct hlist_node       node;
        struct list_head        list;
        struct list_head        listen_list;
        struct cma_device       *cma_dev;

        enum cma_state          state;
        spinlock_t              lock;
        struct completion       comp;
        atomic_t                refcount;
        wait_queue_head_t       wait_remove;
        atomic_t                dev_remove;

        int                     backlog;
        int                     timeout_ms;
        struct ib_sa_query      *query;
        int                     query_id;
        union {
                struct ib_cm_id *ib;
        } cm_id;

        u32                     seq_num;
        u32                     qp_num;
        enum ib_qp_type         qp_type;
        u8                      srq;
};

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

union cma_ip_addr {
        struct in6_addr ip6;
        struct {
                __u32 pad[3];
                __u32 addr;
        } ip4;
};

struct cma_hdr {
        u8 cma_version;
        u8 ip_version;  /* IP version: 7:4 */
        __u16 port;
        union cma_ip_addr src_addr;
        union cma_ip_addr dst_addr;
};

struct sdp_hh {
        u8 bsdh[16];
        u8 sdp_version; /* Major version: 7:4 */
        u8 ip_version;  /* IP version: 7:4 */
        u8 sdp_specific1[10];
        __u16 port;
        __u16 sdp_specific2;
        union cma_ip_addr src_addr;
        union cma_ip_addr dst_addr;
};

struct sdp_hah {
        u8 bsdh[16];
        u8 sdp_version;
};

#define CMA_VERSION 0x00
#define SDP_MAJ_VERSION 0x2

static int cma_comp(struct rdma_id_private *id_priv, enum cma_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 cma_state comp, enum cma_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 cma_state cma_exch(struct rdma_id_private *id_priv,
                               enum cma_state exch)
{
        unsigned long flags;
        enum cma_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(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 inline u8 sdp_get_majv(u8 sdp_version)
{
        return sdp_version >> 4;
}

static inline u8 sdp_get_ip_ver(struct sdp_hh *hh)
{
        return hh->ip_version >> 4;
}

static inline void sdp_set_ip_ver(struct sdp_hh *hh, u8 ip_ver)
{
        hh->ip_version = (ip_ver << 4) | (hh->ip_version & 0xF);
}

static void cma_attach_to_dev(struct rdma_id_private *id_priv,
                              struct cma_device *cma_dev)
{
        atomic_inc(&cma_dev->refcount);
        id_priv->cma_dev = cma_dev;
        id_priv->id.device = cma_dev->device;
        list_add_tail(&id_priv->list, &cma_dev->id_list);
}

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

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

static int cma_acquire_ib_dev(struct rdma_id_private *id_priv)
{
        struct cma_device *cma_dev;
        union ib_gid gid;
        int ret = -ENODEV;

        ib_addr_get_sgid(&id_priv->id.route.addr.dev_addr, &gid),

        mutex_lock(&lock);
        list_for_each_entry(cma_dev, &dev_list, list) {
                ret = ib_find_cached_gid(cma_dev->device, &gid,
                                         &id_priv->id.port_num, NULL);
                if (!ret) {
                        cma_attach_to_dev(id_priv, cma_dev);
                        break;
                }
        }
        mutex_unlock(&lock);
        return ret;
}

static int cma_acquire_dev(struct rdma_id_private *id_priv)
{
        switch (id_priv->id.route.addr.dev_addr.dev_type) {
        case IB_NODE_CA:
                return cma_acquire_ib_dev(id_priv);
        default:
                return -ENODEV;
        }
}

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

static void cma_release_remove(struct rdma_id_private *id_priv)
{
        if (atomic_dec_and_test(&id_priv->dev_remove))
                wake_up(&id_priv->wait_remove);
}

struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
                                  void *context, enum rdma_port_space ps)
{
        struct rdma_id_private *id_priv;

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

        id_priv->state = CMA_IDLE;
        id_priv->id.context = context;
        id_priv->id.event_handler = event_handler;
        id_priv->id.ps = ps;
        spin_lock_init(&id_priv->lock);
        init_completion(&id_priv->comp);
        atomic_set(&id_priv->refcount, 1);
        init_waitqueue_head(&id_priv->wait_remove);
        atomic_set(&id_priv->dev_remove, 0);
        INIT_LIST_HEAD(&id_priv->listen_list);
        get_random_bytes(&id_priv->seq_num, sizeof id_priv->seq_num);

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

static int cma_init_ib_qp(struct rdma_id_private *id_priv, struct ib_qp *qp)
{
        struct ib_qp_attr qp_attr;
        struct rdma_dev_addr *dev_addr;
        int ret;

        dev_addr = &id_priv->id.route.addr.dev_addr;
        ret = ib_find_cached_pkey(id_priv->id.device, id_priv->id.port_num,
                                  ib_addr_get_pkey(dev_addr),
                                  &qp_attr.pkey_index);
        if (ret)
                return ret;

        qp_attr.qp_state = IB_QPS_INIT;
        qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE;
        qp_attr.port_num = id_priv->id.port_num;
        return ib_modify_qp(qp, &qp_attr, IB_QP_STATE | IB_QP_ACCESS_FLAGS |
                                          IB_QP_PKEY_INDEX | IB_QP_PORT);
}

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 = ib_create_qp(pd, qp_init_attr);
        if (IS_ERR(qp))
                return PTR_ERR(qp);

        switch (id->device->node_type) {
        case IB_NODE_CA:
                ret = cma_init_ib_qp(id_priv, qp);
                break;
        default:
                ret = -ENOSYS;
                break;
        }

        if (ret)
                goto err;

        id->qp = qp;
        id_priv->qp_num = qp->qp_num;
        id_priv->qp_type = qp->qp_type;
        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)
{
        ib_destroy_qp(id->qp);
}
EXPORT_SYMBOL(rdma_destroy_qp);

static int cma_modify_qp_rtr(struct rdma_cm_id *id)
{
        struct ib_qp_attr qp_attr;
        int qp_attr_mask, ret;

        if (!id->qp)
                return 0;

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

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

        qp_attr.qp_state = IB_QPS_RTR;
        ret = rdma_init_qp_attr(id, &qp_attr, &qp_attr_mask);
        if (ret)
                return ret;

        return ib_modify_qp(id->qp, &qp_attr, qp_attr_mask);
}

static int cma_modify_qp_rts(struct rdma_cm_id *id)
{
        struct ib_qp_attr qp_attr;
        int qp_attr_mask, ret;

        if (!id->qp)
                return 0;

        qp_attr.qp_state = IB_QPS_RTS;
        ret = rdma_init_qp_attr(id, &qp_attr, &qp_attr_mask);
        if (ret)
                return ret;

        return ib_modify_qp(id->qp, &qp_attr, qp_attr_mask);
}

static int cma_modify_qp_err(struct rdma_cm_id *id)
{
        struct ib_qp_attr qp_attr;

        if (!id->qp)
                return 0;

        qp_attr.qp_state = IB_QPS_ERR;
        return ib_modify_qp(id->qp, &qp_attr, IB_QP_STATE);
}

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;

        id_priv = container_of(id, struct rdma_id_private, id);
        switch (id_priv->id.device->node_type) {
        case IB_NODE_CA:
                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;
                break;
        default:
                ret = -ENOSYS;
                break;
        }

        return ret;
}
EXPORT_SYMBOL(rdma_init_qp_attr);

static inline int cma_zero_addr(struct sockaddr *addr)
{
        struct in6_addr *ip6;

        if (addr->sa_family == AF_INET)
                return ZERONET(((struct sockaddr_in *) addr)->sin_addr.s_addr);
        else {
                ip6 = &((struct sockaddr_in6 *) addr)->sin6_addr;
                return (ip6->s6_addr32[0] | ip6->s6_addr32[1] |
                        ip6->s6_addr32[2] | ip6->s6_addr32[3]) == 0;
        }
}

static inline int cma_loopback_addr(struct sockaddr *addr)
{
        return LOOPBACK(((struct sockaddr_in *) addr)->sin_addr.s_addr);
}

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

static inline int cma_any_port(struct sockaddr *addr)
{
        return !((struct sockaddr_in *) addr)->sin_port;
}

static int cma_get_net_info(void *hdr, enum rdma_port_space ps,
                            u8 *ip_ver, __u16 *port,
                            union cma_ip_addr **src, union cma_ip_addr **dst)
{
        switch (ps) {
        case RDMA_PS_SDP:
                if (sdp_get_majv(((struct sdp_hh *) hdr)->sdp_version) !=
                    SDP_MAJ_VERSION)
                        return -EINVAL;

                *ip_ver = sdp_get_ip_ver(hdr);
                *port   = ((struct sdp_hh *) hdr)->port;
                *src    = &((struct sdp_hh *) hdr)->src_addr;
                *dst    = &((struct sdp_hh *) hdr)->dst_addr;
                break;
        default:
                if (((struct cma_hdr *) hdr)->cma_version != CMA_VERSION)
                        return -EINVAL;

                *ip_ver = cma_get_ip_ver(hdr);
                *port   = ((struct cma_hdr *) hdr)->port;
                *src    = &((struct cma_hdr *) hdr)->src_addr;
                *dst    = &((struct cma_hdr *) hdr)->dst_addr;
                break;
        }

        if (*ip_ver != 4 && *ip_ver != 6)
                return -EINVAL;
        return 0;
}

static void cma_save_net_info(struct rdma_addr *addr,
                              struct rdma_addr *listen_addr,
                              u8 ip_ver, __u16 port,
                              union cma_ip_addr *src, union cma_ip_addr *dst)
{
        struct sockaddr_in *listen4, *ip4;
        struct sockaddr_in6 *listen6, *ip6;

        switch (ip_ver) {
        case 4:
                listen4 = (struct sockaddr_in *) &listen_addr->src_addr;
                ip4 = (struct sockaddr_in *) &addr->src_addr;
                ip4->sin_family = listen4->sin_family;
                ip4->sin_addr.s_addr = dst->ip4.addr;
                ip4->sin_port = listen4->sin_port;

                ip4 = (struct sockaddr_in *) &addr->dst_addr;
                ip4->sin_family = listen4->sin_family;
                ip4->sin_addr.s_addr = src->ip4.addr;
                ip4->sin_port = port;
                break;
        case 6:
                listen6 = (struct sockaddr_in6 *) &listen_addr->src_addr;
                ip6 = (struct sockaddr_in6 *) &addr->src_addr;
                ip6->sin6_family = listen6->sin6_family;
                ip6->sin6_addr = dst->ip6;
                ip6->sin6_port = listen6->sin6_port;

                ip6 = (struct sockaddr_in6 *) &addr->dst_addr;
                ip6->sin6_family = listen6->sin6_family;
                ip6->sin6_addr = src->ip6;
                ip6->sin6_port = port;
                break;
        default:
                break;
        }
}

static inline int cma_user_data_offset(enum rdma_port_space ps)
{
        switch (ps) {
        case RDMA_PS_SDP:
                return 0;
        default:
                return sizeof(struct cma_hdr);
        }
}

static int cma_notify_user(struct rdma_id_private *id_priv,
                           enum rdma_cm_event_type type, int status,
                           void *data, u8 data_len)
{
        struct rdma_cm_event event;

        event.event = type;
        event.status = status;
        event.private_data = data;
        event.private_data_len = data_len;

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

static void cma_cancel_route(struct rdma_id_private *id_priv)
{
        switch (id_priv->id.device->node_type) {
        case IB_NODE_CA:
                if (id_priv->query)
                        ib_sa_cancel_query(id_priv->query_id, id_priv->query);
                break;
        default:
                break;
        }
}

static inline int cma_internal_listen(struct rdma_id_private *id_priv)
{
        return (id_priv->state == CMA_LISTEN) && id_priv->cma_dev &&
               cma_any_addr(&id_priv->id.route.addr.src_addr);
}

static void cma_destroy_listen(struct rdma_id_private *id_priv)
{
        cma_exch(id_priv, CMA_DESTROYING);

        if (id_priv->cma_dev) {
                switch (id_priv->id.device->node_type) {
                case IB_NODE_CA:
                        if (id_priv->cm_id.ib && !IS_ERR(id_priv->cm_id.ib))
                                ib_destroy_cm_id(id_priv->cm_id.ib);
                        break;
                default:
                        break;
                }
                cma_detach_from_dev(id_priv);
        }
        list_del(&id_priv->listen_list);

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

        kfree(id_priv);
}

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

        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);
                cma_destroy_listen(dev_id_priv);
        }
        mutex_unlock(&lock);
}

static void cma_cancel_operation(struct rdma_id_private *id_priv,
                                 enum cma_state state)
{
        switch (state) {
        case CMA_ADDR_QUERY:
                rdma_addr_cancel(&id_priv->id.route.addr.dev_addr);
                break;
        case CMA_ROUTE_QUERY:
                cma_cancel_route(id_priv);
                break;
        case CMA_LISTEN:
                if (cma_any_addr(&id_priv->id.route.addr.src_addr) &&
                    !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;

        if (!bind_list)
                return;

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

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

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

        if (id_priv->cma_dev) {
                switch (id->device->node_type) {
                case IB_NODE_CA:
                        if (id_priv->cm_id.ib && !IS_ERR(id_priv->cm_id.ib))
                                ib_destroy_cm_id(id_priv->cm_id.ib);
                        break;
                default:
                        break;
                }
                mutex_lock(&lock);
                cma_detach_from_dev(id_priv);
                mutex_unlock(&lock);
        }

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

        kfree(id_priv->id.route.path_rec);
        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->id);
        if (ret)
                goto reject;

        ret = cma_modify_qp_rts(&id_priv->id);
        if (ret)
                goto reject;

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

        return 0;
reject:
        cma_modify_qp_err(&id_priv->id);
        ib_send_cm_rej(id_priv->cm_id.ib, IB_CM_REJ_CONSUMER_DEFINED,
                       NULL, 0, NULL, 0);
        return ret;
}

static int cma_verify_rep(struct rdma_id_private *id_priv, void *data)
{
        if (id_priv->id.ps == RDMA_PS_SDP &&
            sdp_get_majv(((struct sdp_hah *) data)->sdp_version) !=
            SDP_MAJ_VERSION)
                return -EINVAL;

        return 0;
}

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

        ret = cma_modify_qp_rts(&id_priv->id);
        if (ret)
                goto reject;

        return 0;
reject:
        cma_modify_qp_err(&id_priv->id);
        ib_send_cm_rej(id_priv->cm_id.ib, IB_CM_REJ_CONSUMER_DEFINED,
                       NULL, 0, NULL, 0);
        return ret;
}

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;
        enum rdma_cm_event_type event;
        u8 private_data_len = 0;
        int ret = 0, status = 0;

        atomic_inc(&id_priv->dev_remove);
        if (!cma_comp(id_priv, CMA_CONNECT))
                goto out;

        switch (ib_event->event) {
        case IB_CM_REQ_ERROR:
        case IB_CM_REP_ERROR:
                event = RDMA_CM_EVENT_UNREACHABLE;
                status = -ETIMEDOUT;
                break;
        case IB_CM_REP_RECEIVED:
                status = cma_verify_rep(id_priv, ib_event->private_data);
                if (status)
                        event = RDMA_CM_EVENT_CONNECT_ERROR;
                else if (id_priv->id.qp && id_priv->id.ps != RDMA_PS_SDP) {
                        status = cma_rep_recv(id_priv);
                        event = status ? RDMA_CM_EVENT_CONNECT_ERROR :
                                         RDMA_CM_EVENT_ESTABLISHED;
                } else
                        event = RDMA_CM_EVENT_CONNECT_RESPONSE;
                private_data_len = IB_CM_REP_PRIVATE_DATA_SIZE;
                break;
        case IB_CM_RTU_RECEIVED:
                status = cma_rtu_recv(id_priv);
                event = status ? RDMA_CM_EVENT_CONNECT_ERROR :
                                 RDMA_CM_EVENT_ESTABLISHED;
                break;
        case IB_CM_DREQ_ERROR:
                status = -ETIMEDOUT; /* fall through */
        case IB_CM_DREQ_RECEIVED:
        case IB_CM_DREP_RECEIVED:
                if (!cma_comp_exch(id_priv, CMA_CONNECT, CMA_DISCONNECT))
                        goto out;
                event = RDMA_CM_EVENT_DISCONNECTED;
                break;
        case IB_CM_TIMEWAIT_EXIT:
        case IB_CM_MRA_RECEIVED:
                /* ignore event */
                goto out;
        case IB_CM_REJ_RECEIVED:
                cma_modify_qp_err(&id_priv->id);
                status = ib_event->param.rej_rcvd.reason;
                event = RDMA_CM_EVENT_REJECTED;
                private_data_len = IB_CM_REJ_PRIVATE_DATA_SIZE;
                break;
        default:
                printk(KERN_ERR "RDMA CMA: unexpected IB CM event: %d",
                       ib_event->event);
                goto out;
        }

        ret = cma_notify_user(id_priv, event, status, ib_event->private_data,
                              private_data_len);
        if (ret) {
                /* Destroy the CM ID by returning a non-zero value. */
                id_priv->cm_id.ib = NULL;
                cma_exch(id_priv, CMA_DESTROYING);
                cma_release_remove(id_priv);
                rdma_destroy_id(&id_priv->id);
                return ret;
        }
out:
        cma_release_remove(id_priv);
        return ret;
}

static struct rdma_id_private *cma_new_id(struct rdma_cm_id *listen_id,
                                          struct ib_cm_event *ib_event)
{
        struct rdma_id_private *id_priv;
        struct rdma_cm_id *id;
        struct rdma_route *rt;
        union cma_ip_addr *src, *dst;
        __u16 port;
        u8 ip_ver;

        id = rdma_create_id(listen_id->event_handler, listen_id->context,
                            listen_id->ps);
        if (IS_ERR(id))
                return NULL;

        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;

        if (cma_get_net_info(ib_event->private_data, listen_id->ps,
                             &ip_ver, &port, &src, &dst))
                goto err;

        cma_save_net_info(&id->route.addr, &listen_id->route.addr,
                          ip_ver, port, src, dst);
        rt->path_rec[0] = *ib_event->param.req_rcvd.primary_path;
        if (rt->num_paths == 2)
                rt->path_rec[1] = *ib_event->param.req_rcvd.alternate_path;

        ib_addr_set_sgid(&rt->addr.dev_addr, &rt->path_rec[0].sgid);
        ib_addr_set_dgid(&rt->addr.dev_addr, &rt->path_rec[0].dgid);
        ib_addr_set_pkey(&rt->addr.dev_addr, be16_to_cpu(rt->path_rec[0].pkey));
        rt->addr.dev_addr.dev_type = IB_NODE_CA;

        id_priv = container_of(id, struct rdma_id_private, id);
        id_priv->state = CMA_CONNECT;
        return id_priv;
err:
        rdma_destroy_id(id);
        return NULL;
}

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;
        int offset, ret;

        listen_id = cm_id->context;
        atomic_inc(&listen_id->dev_remove);
        if (!cma_comp(listen_id, CMA_LISTEN)) {
                ret = -ECONNABORTED;
                goto out;
        }

        conn_id = cma_new_id(&listen_id->id, ib_event);
        if (!conn_id) {
                ret = -ENOMEM;
                goto out;
        }

        atomic_inc(&conn_id->dev_remove);
        ret = cma_acquire_ib_dev(conn_id);
        if (ret) {
                ret = -ENODEV;
                cma_release_remove(conn_id);
                rdma_destroy_id(&conn_id->id);
                goto out;
        }

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

        offset = cma_user_data_offset(listen_id->id.ps);
        ret = cma_notify_user(conn_id, RDMA_CM_EVENT_CONNECT_REQUEST, 0,
                              ib_event->private_data + offset,
                              IB_CM_REQ_PRIVATE_DATA_SIZE - offset);
        if (ret) {
                /* Destroy the CM ID by returning a non-zero value. */
                conn_id->cm_id.ib = NULL;
                cma_exch(conn_id, CMA_DESTROYING);
                cma_release_remove(conn_id);
                rdma_destroy_id(&conn_id->id);
        }
out:
        cma_release_remove(listen_id);
        return ret;
}

static __be64 cma_get_service_id(enum rdma_port_space ps, struct sockaddr *addr)
{
        return cpu_to_be64(((u64)ps << 16) +
               be16_to_cpu(((struct sockaddr_in *) addr)->sin_port));
}

static void cma_set_compare_data(enum rdma_port_space ps, struct sockaddr *addr,
                                 struct ib_cm_compare_data *compare)
{
        struct cma_hdr *cma_data, *cma_mask;
        struct sdp_hh *sdp_data, *sdp_mask;
        __u32 ip4_addr;
        struct in6_addr ip6_addr;

        memset(compare, 0, sizeof *compare);
        cma_data = (void *) compare->data;
        cma_mask = (void *) compare->mask;
        sdp_data = (void *) compare->data;
        sdp_mask = (void *) compare->mask;

        switch (addr->sa_family) {
        case AF_INET:
                ip4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
                if (ps == RDMA_PS_SDP) {
                        sdp_set_ip_ver(sdp_data, 4);
                        sdp_set_ip_ver(sdp_mask, 0xF);
                        sdp_data->dst_addr.ip4.addr = ip4_addr;
                        sdp_mask->dst_addr.ip4.addr = ~0;
                } else {
                        cma_set_ip_ver(cma_data, 4);
                        cma_set_ip_ver(cma_mask, 0xF);
                        cma_data->dst_addr.ip4.addr = ip4_addr;
                        cma_mask->dst_addr.ip4.addr = ~0;
                }
                break;
        case AF_INET6:
                ip6_addr = ((struct sockaddr_in6 *) addr)->sin6_addr;
                if (ps == RDMA_PS_SDP) {
                        sdp_set_ip_ver(sdp_data, 6);
                        sdp_set_ip_ver(sdp_mask, 0xF);
                        sdp_data->dst_addr.ip6 = ip6_addr;
                        memset(&sdp_mask->dst_addr.ip6, 0xFF,
                               sizeof sdp_mask->dst_addr.ip6);
                } else {
                        cma_set_ip_ver(cma_data, 6);
                        cma_set_ip_ver(cma_mask, 0xF);
                        cma_data->dst_addr.ip6 = ip6_addr;
                        memset(&cma_mask->dst_addr.ip6, 0xFF,
                               sizeof cma_mask->dst_addr.ip6);
                }
                break;
        default:
                break;
        }
}

static int cma_ib_listen(struct rdma_id_private *id_priv)
{
        struct ib_cm_compare_data compare_data;
        struct sockaddr *addr;
        __be64 svc_id;
        int ret;

        id_priv->cm_id.ib = ib_create_cm_id(id_priv->id.device, cma_req_handler,
                                            id_priv);
        if (IS_ERR(id_priv->cm_id.ib))
                return PTR_ERR(id_priv->cm_id.ib);

        addr = &id_priv->id.route.addr.src_addr;
        svc_id = cma_get_service_id(id_priv->id.ps, addr);
        if (cma_any_addr(addr))
                ret = ib_cm_listen(id_priv->cm_id.ib, svc_id, 0, NULL);

        else {
                cma_set_compare_data(id_priv->id.ps, addr, &compare_data);
                ret = ib_cm_listen(id_priv->cm_id.ib, svc_id, 0, &compare_data);
        }

        if (ret) {
                ib_destroy_cm_id(id_priv->cm_id.ib);
                id_priv->cm_id.ib = 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;
        int ret;

        id = rdma_create_id(cma_listen_handler, id_priv, id_priv->id.ps);
        if (IS_ERR(id))
                return;

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

        dev_id_priv->state = CMA_ADDR_BOUND;
        memcpy(&id->route.addr.src_addr, &id_priv->id.route.addr.src_addr,
               ip_addr_size(&id_priv->id.route.addr.src_addr));

        cma_attach_to_dev(dev_id_priv, cma_dev);
        list_add_tail(&dev_id_priv->listen_list, &id_priv->listen_list);

        ret = rdma_listen(id, id_priv->backlog);
        if (ret)
                goto err;

        return;
err:
        cma_destroy_listen(dev_id_priv);
}

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);
}

static int cma_bind_any(struct rdma_cm_id *id, sa_family_t af)
{
        struct sockaddr_in addr_in;

        memset(&addr_in, 0, sizeof addr_in);
        addr_in.sin_family = af;
        return rdma_bind_addr(id, (struct sockaddr *) &addr_in);
}

int rdma_listen(struct rdma_cm_id *id, int backlog)
{
        struct rdma_id_private *id_priv;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (id_priv->state == CMA_IDLE) {
                ret = cma_bind_any(id, AF_INET);
                if (ret)
                        return ret;
        }

        if (!cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_LISTEN))
                return -EINVAL;

        id_priv->backlog = backlog;
        if (id->device) {
                switch (id->device->node_type) {
                case IB_NODE_CA:
                        ret = cma_ib_listen(id_priv);
                        if (ret)
                                goto err;
                        break;
                default:
                        ret = -ENOSYS;
                        goto err;
                }
        } else
                cma_listen_on_all(id_priv);

        return 0;
err:
        id_priv->backlog = 0;
        cma_comp_exch(id_priv, CMA_LISTEN, CMA_ADDR_BOUND);
        return ret;
}
EXPORT_SYMBOL(rdma_listen);

static void cma_query_handler(int status, struct ib_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 = CMA_ROUTE_QUERY;
                work->new_state = CMA_ADDR_RESOLVED;
                work->event.event = RDMA_CM_EVENT_ROUTE_ERROR;
        }

        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 *addr = &id_priv->id.route.addr.dev_addr;
        struct ib_sa_path_rec path_rec;

        memset(&path_rec, 0, sizeof path_rec);
        ib_addr_get_sgid(addr, &path_rec.sgid);
        ib_addr_get_dgid(addr, &path_rec.dgid);
        path_rec.pkey = cpu_to_be16(ib_addr_get_pkey(addr));
        path_rec.numb_path = 1;

        id_priv->query_id = ib_sa_path_rec_get(id_priv->id.device,
                                id_priv->id.port_num, &path_rec,
                                IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID |
                                IB_SA_PATH_REC_PKEY | IB_SA_PATH_REC_NUMB_PATH,
                                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(void *data)
{
        struct cma_work *work = data;
        struct rdma_id_private *id_priv = work->id;
        int destroy = 0;

        atomic_inc(&id_priv->dev_remove);
        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, CMA_DESTROYING);
                destroy = 1;
        }
out:
        cma_release_remove(id_priv);
        cma_deref_id(id_priv);
        if (destroy)
                rdma_destroy_id(&id_priv->id);
        kfree(work);
}

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;

        work->id = id_priv;
        INIT_WORK(&work->work, cma_work_handler, work);
        work->old_state = CMA_ROUTE_QUERY;
        work->new_state = CMA_ROUTE_RESOLVED;
        work->event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;

        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;
}

int rdma_set_ib_paths(struct rdma_cm_id *id,
                      struct ib_sa_path_rec *path_rec, int num_paths)
{
        struct rdma_id_private *id_priv;
        int ret;

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

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

        memcpy(id->route.path_rec, path_rec, sizeof *path_rec * num_paths);
        return 0;
err:
        cma_comp_exch(id_priv, CMA_ROUTE_RESOLVED, CMA_ADDR_RESOLVED);
        return ret;
}
EXPORT_SYMBOL(rdma_set_ib_paths);

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, CMA_ADDR_RESOLVED, CMA_ROUTE_QUERY))
                return -EINVAL;

        atomic_inc(&id_priv->refcount);
        switch (id->device->node_type) {
        case IB_NODE_CA:
                ret = cma_resolve_ib_route(id_priv, timeout_ms);
                break;
        default:
                ret = -ENOSYS;
                break;
        }
        if (ret)
                goto err;

        return 0;
err:
        cma_comp_exch(id_priv, CMA_ROUTE_QUERY, CMA_ADDR_RESOLVED);
        cma_deref_id(id_priv);
        return ret;
}
EXPORT_SYMBOL(rdma_resolve_route);

static int cma_bind_loopback(struct rdma_id_private *id_priv)
{
        struct cma_device *cma_dev;
        struct ib_port_attr port_attr;
        union ib_gid gid;
        u16 pkey;
        int ret;
        u8 p;

        mutex_lock(&lock);
        list_for_each_entry(cma_dev, &dev_list, list)
                for (p = 1; p <= cma_dev->device->phys_port_cnt; ++p)
                        if (!ib_query_port (cma_dev->device, p, &port_attr) &&
                            port_attr.state == IB_PORT_ACTIVE)
                                goto port_found;

        if (!list_empty(&dev_list)) {
                p = 1;
                cma_dev = list_entry(dev_list.next, struct cma_device, list);
        } else {
                ret = -ENODEV;
                goto out;
        }

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

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

        ib_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);
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;
        enum rdma_cm_event_type event;

        atomic_inc(&id_priv->dev_remove);
        if (!id_priv->cma_dev && !status)
                status = cma_acquire_dev(id_priv);

        if (status) {
                if (!cma_comp_exch(id_priv, CMA_ADDR_QUERY, CMA_ADDR_BOUND))
                        goto out;
                event = RDMA_CM_EVENT_ADDR_ERROR;
        } else {
                if (!cma_comp_exch(id_priv, CMA_ADDR_QUERY, CMA_ADDR_RESOLVED))
                        goto out;
                memcpy(&id_priv->id.route.addr.src_addr, src_addr,
                       ip_addr_size(src_addr));
                event = RDMA_CM_EVENT_ADDR_RESOLVED;
        }

        if (cma_notify_user(id_priv, event, status, NULL, 0)) {
                cma_exch(id_priv, CMA_DESTROYING);
                cma_release_remove(id_priv);
                cma_deref_id(id_priv);
                rdma_destroy_id(&id_priv->id);
                return;
        }
out:
        cma_release_remove(id_priv);
        cma_deref_id(id_priv);
}

static int cma_resolve_loopback(struct rdma_id_private *id_priv)
{
        struct cma_work *work;
        struct sockaddr_in *src_in, *dst_in;
        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;
        }

        ib_addr_get_sgid(&id_priv->id.route.addr.dev_addr, &gid);
        ib_addr_set_dgid(&id_priv->id.route.addr.dev_addr, &gid);

        if (cma_zero_addr(&id_priv->id.route.addr.src_addr)) {
                src_in = (struct sockaddr_in *)&id_priv->id.route.addr.src_addr;
                dst_in = (struct sockaddr_in *)&id_priv->id.route.addr.dst_addr;
                src_in->sin_family = dst_in->sin_family;
                src_in->sin_addr.s_addr = dst_in->sin_addr.s_addr;
        }

        work->id = id_priv;
        INIT_WORK(&work->work, cma_work_handler, work);
        work->old_state = CMA_ADDR_QUERY;
        work->new_state = CMA_ADDR_RESOLVED;
        work->event.event = RDMA_CM_EVENT_ADDR_RESOLVED;
        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)
                return rdma_bind_addr(id, src_addr);
        else
                return cma_bind_any(id, dst_addr->sa_family);
}

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);
        if (id_priv->state == CMA_IDLE) {
                ret = cma_bind_addr(id, src_addr, dst_addr);
                if (ret)
                        return ret;
        }

        if (!cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_ADDR_QUERY))
                return -EINVAL;

        atomic_inc(&id_priv->refcount);
        memcpy(&id->route.addr.dst_addr, dst_addr, ip_addr_size(dst_addr));
        if (cma_any_addr(dst_addr))
                ret = cma_resolve_loopback(id_priv);
        else
                ret = rdma_resolve_ip(&id->route.addr.src_addr, 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, CMA_ADDR_QUERY, CMA_ADDR_BOUND);
        cma_deref_id(id_priv);
        return ret;
}
EXPORT_SYMBOL(rdma_resolve_addr);

static void cma_bind_port(struct rdma_bind_list *bind_list,
                          struct rdma_id_private *id_priv)
{
        struct sockaddr_in *sin;

        sin = (struct sockaddr_in *) &id_priv->id.route.addr.src_addr;
        sin->sin_port = htons(bind_list->port);
        id_priv->bind_list = bind_list;
        hlist_add_head(&id_priv->node, &bind_list->owners);
}

static int cma_alloc_port(struct idr *ps, struct rdma_id_private *id_priv,
                          unsigned short snum)
{
        struct rdma_bind_list *bind_list;
        int port, start, ret;

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

        start = snum ? snum : sysctl_local_port_range[0];

        do {
                ret = idr_get_new_above(ps, bind_list, start, &port);
        } while ((ret == -EAGAIN) && idr_pre_get(ps, GFP_KERNEL));

        if (ret)
                goto err;

        if ((snum && port != snum) ||
            (!snum && port > sysctl_local_port_range[1])) {
                idr_remove(ps, port);
                ret = -EADDRNOTAVAIL;
                goto err;
        }

        bind_list->ps = ps;
        bind_list->port = (unsigned short) port;
        cma_bind_port(bind_list, id_priv);
        return 0;
err:
        kfree(bind_list);
        return ret;
}

static int cma_use_port(struct idr *ps, struct rdma_id_private *id_priv)
{
        struct rdma_id_private *cur_id;
        struct sockaddr_in *sin, *cur_sin;
        struct rdma_bind_list *bind_list;
        struct hlist_node *node;
        unsigned short snum;

        sin = (struct sockaddr_in *) &id_priv->id.route.addr.src_addr;
        snum = ntohs(sin->sin_port);
        if (snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
                return -EACCES;

        bind_list = idr_find(ps, snum);
        if (!bind_list)
                return cma_alloc_port(ps, id_priv, snum);

        /*
         * We don't support binding to any address if anyone is bound to
         * a specific address on the same port.
         */
        if (cma_any_addr(&id_priv->id.route.addr.src_addr))
                return -EADDRNOTAVAIL;

        hlist_for_each_entry(cur_id, node, &bind_list->owners, node) {
                if (cma_any_addr(&cur_id->id.route.addr.src_addr))
                        return -EADDRNOTAVAIL;
                
                cur_sin = (struct sockaddr_in *) &cur_id->id.route.addr.src_addr;
                if (sin->sin_addr.s_addr == cur_sin->sin_addr.s_addr)
                        return -EADDRINUSE;
        }

        cma_bind_port(bind_list, id_priv);
        return 0;
}

static int cma_get_port(struct rdma_id_private *id_priv)
{
        struct idr *ps;
        int ret;

        switch (id_priv->id.ps) {
        case RDMA_PS_SDP:
                ps = &sdp_ps;
                break;
        case RDMA_PS_TCP:
                ps = &tcp_ps;
                break;
        default:
                return -EPROTONOSUPPORT;
        }

        mutex_lock(&lock);
        if (cma_any_port(&id_priv->id.route.addr.src_addr))
                ret = cma_alloc_port(ps, id_priv, 0);
        else
                ret = cma_use_port(ps, id_priv);
        mutex_unlock(&lock);

        return ret;
}

int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
{
        struct rdma_id_private *id_priv;
        int ret;

        if (addr->sa_family != AF_INET)
                return -EAFNOSUPPORT;

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

        if (!cma_any_addr(addr)) {
                ret = rdma_translate_ip(addr, &id->route.addr.dev_addr);
                if (!ret)
                        ret = cma_acquire_dev(id_priv);
                if (ret)
                        goto err;
        }

        memcpy(&id->route.addr.src_addr, addr, ip_addr_size(addr));
        ret = cma_get_port(id_priv);
        if (ret)
                goto err;

        return 0;
err:
        cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_IDLE);
        return ret;
}
EXPORT_SYMBOL(rdma_bind_addr);

static int cma_format_hdr(void *hdr, enum rdma_port_space ps,
                          struct rdma_route *route)
{
        struct sockaddr_in *src4, *dst4;
        struct cma_hdr *cma_hdr;
        struct sdp_hh *sdp_hdr;

        src4 = (struct sockaddr_in *) &route->addr.src_addr;
        dst4 = (struct sockaddr_in *) &route->addr.dst_addr;

        switch (ps) {
        case RDMA_PS_SDP:
                sdp_hdr = hdr;
                if (sdp_get_majv(sdp_hdr->sdp_version) != SDP_MAJ_VERSION)
                        return -EINVAL;
                sdp_set_ip_ver(sdp_hdr, 4);
                sdp_hdr->src_addr.ip4.addr = src4->sin_addr.s_addr;
                sdp_hdr->dst_addr.ip4.addr = dst4->sin_addr.s_addr;
                sdp_hdr->port = src4->sin_port;
                break;
        default:
                cma_hdr = hdr;
                cma_hdr->cma_version = CMA_VERSION;
                cma_set_ip_ver(cma_hdr, 4);
                cma_hdr->src_addr.ip4.addr = src4->sin_addr.s_addr;
                cma_hdr->dst_addr.ip4.addr = dst4->sin_addr.s_addr;
                cma_hdr->port = src4->sin_port;
                break;
        }
        return 0;
}

static int cma_connect_ib(struct rdma_id_private *id_priv,
                          struct rdma_conn_param *conn_param)
{
        struct ib_cm_req_param req;
        struct rdma_route *route;
        void *private_data;
        int offset, ret;

        memset(&req, 0, sizeof req);
        offset = cma_user_data_offset(id_priv->id.ps);
        req.private_data_len = offset + conn_param->private_data_len;
        private_data = kzalloc(req.private_data_len, GFP_ATOMIC);
        if (!private_data)
                return -ENOMEM;

        if (conn_param->private_data && conn_param->private_data_len)
                memcpy(private_data + offset, conn_param->private_data,
                       conn_param->private_data_len);

        id_priv->cm_id.ib = ib_create_cm_id(id_priv->id.device, cma_ib_handler,
                                            id_priv);
        if (IS_ERR(id_priv->cm_id.ib)) {
                ret = PTR_ERR(id_priv->cm_id.ib);
                goto out;
        }

        route = &id_priv->id.route;
        ret = cma_format_hdr(private_data, id_priv->id.ps, route);
        if (ret)
                goto out;
        req.private_data = private_data;

        req.primary_path = &route->path_rec[0];
        if (route->num_paths == 2)
                req.alternate_path = &route->path_rec[1];

        req.service_id = cma_get_service_id(id_priv->id.ps,
                                            &route->addr.dst_addr);
        req.qp_num = id_priv->qp_num;
        req.qp_type = id_priv->qp_type;
        req.starting_psn = id_priv->seq_num;
        req.responder_resources = conn_param->responder_resources;
        req.initiator_depth = conn_param->initiator_depth;
        req.flow_control = conn_param->flow_control;
        req.retry_count = conn_param->retry_count;
        req.rnr_retry_count = conn_param->rnr_retry_count;
        req.remote_cm_response_timeout = CMA_CM_RESPONSE_TIMEOUT;
        req.local_cm_response_timeout = CMA_CM_RESPONSE_TIMEOUT;
        req.max_cm_retries = CMA_MAX_CM_RETRIES;
        req.srq = id_priv->srq ? 1 : 0;

        ret = ib_send_cm_req(id_priv->cm_id.ib, &req);
out:
        kfree(private_data);
        return ret;
}

int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
{
        struct rdma_id_private *id_priv;
        int ret;

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

        if (!id->qp) {
                id_priv->qp_num = conn_param->qp_num;
                id_priv->qp_type = conn_param->qp_type;
                id_priv->srq = conn_param->srq;
        }

        switch (id->device->node_type) {
        case IB_NODE_CA:
                ret = cma_connect_ib(id_priv, conn_param);
                break;
        default:
                ret = -ENOSYS;
                break;
        }
        if (ret)
                goto err;

        return 0;
err:
        cma_comp_exch(id_priv, CMA_CONNECT, CMA_ROUTE_RESOLVED);
        return ret;
}
EXPORT_SYMBOL(rdma_connect);

static int cma_accept_ib(struct rdma_id_private *id_priv,
                         struct rdma_conn_param *conn_param)
{
        struct ib_cm_rep_param rep;
        int ret;

        ret = cma_modify_qp_rtr(&id_priv->id);
        if (ret)
                return ret;

        memset(&rep, 0, sizeof rep);
        rep.qp_num = id_priv->qp_num;
        rep.starting_psn = id_priv->seq_num;
        rep.private_data = conn_param->private_data;
        rep.private_data_len = conn_param->private_data_len;
        rep.responder_resources = conn_param->responder_resources;
        rep.initiator_depth = conn_param->initiator_depth;
        rep.target_ack_delay = CMA_CM_RESPONSE_TIMEOUT;
        rep.failover_accepted = 0;
        rep.flow_control = conn_param->flow_control;
        rep.rnr_retry_count = conn_param->rnr_retry_count;
        rep.srq = id_priv->srq ? 1 : 0;

        return ib_send_cm_rep(id_priv->cm_id.ib, &rep);
}

int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
{
        struct rdma_id_private *id_priv;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (!cma_comp(id_priv, CMA_CONNECT))
                return -EINVAL;

        if (!id->qp && conn_param) {
                id_priv->qp_num = conn_param->qp_num;
                id_priv->qp_type = conn_param->qp_type;
                id_priv->srq = conn_param->srq;
        }

        switch (id->device->node_type) {
        case IB_NODE_CA:
                if (conn_param)
                        ret = cma_accept_ib(id_priv, conn_param);
                else
                        ret = cma_rep_recv(id_priv);
                break;
        default:
                ret = -ENOSYS;
                break;
        }

        if (ret)
                goto reject;

        return 0;
reject:
        cma_modify_qp_err(id);
        rdma_reject(id, NULL, 0);
        return ret;
}
EXPORT_SYMBOL(rdma_accept);

int rdma_reject(struct rdma_cm_id *id, const void *private_data,
                u8 private_data_len)
{
        struct rdma_id_private *id_priv;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (!cma_comp(id_priv, CMA_CONNECT))
                return -EINVAL;

        switch (id->device->node_type) {
        case IB_NODE_CA:
                ret = ib_send_cm_rej(id_priv->cm_id.ib,
                                     IB_CM_REJ_CONSUMER_DEFINED, NULL, 0,
                                     private_data, private_data_len);
                break;
        default:
                ret = -ENOSYS;
                break;
        }
        return ret;
}
EXPORT_SYMBOL(rdma_reject);

int rdma_disconnect(struct rdma_cm_id *id)
{
        struct rdma_id_private *id_priv;
        int ret;

        id_priv = container_of(id, struct rdma_id_private, id);
        if (!cma_comp(id_priv, CMA_CONNECT) &&
            !cma_comp(id_priv, CMA_DISCONNECT))
                return -EINVAL;

        ret = cma_modify_qp_err(id);
        if (ret)
                goto out;

        switch (id->device->node_type) {
        case IB_NODE_CA:
                /* Initiate or respond to a disconnect. */
                if (ib_send_cm_dreq(id_priv->cm_id.ib, NULL, 0))
                        ib_send_cm_drep(id_priv->cm_id.ib, NULL, 0);
                break;
        default:
                break;
        }
out:
        return ret;
}
EXPORT_SYMBOL(rdma_disconnect);

static void cma_add_one(struct ib_device *device)
{
        struct cma_device *cma_dev;
        struct rdma_id_private *id_priv;

        cma_dev = kmalloc(sizeof *cma_dev, GFP_KERNEL);
        if (!cma_dev)
                return;

        cma_dev->device = device;
        cma_dev->node_guid = device->node_guid;
        if (!cma_dev->node_guid)
                goto err;

        init_completion(&cma_dev->comp);
        atomic_set(&cma_dev->refcount, 1);
        INIT_LIST_HEAD(&cma_dev->id_list);
        ib_set_client_data(device, &cma_client, cma_dev);

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

static int cma_remove_id_dev(struct rdma_id_private *id_priv)
{
        enum cma_state state;

        /* Record that we want to remove the device */
        state = cma_exch(id_priv, CMA_DEVICE_REMOVAL);
        if (state == CMA_DESTROYING)
                return 0;

        cma_cancel_operation(id_priv, state);
        wait_event(id_priv->wait_remove, !atomic_read(&id_priv->dev_remove));

        /* Check for destruction from another callback. */
        if (!cma_comp(id_priv, CMA_DEVICE_REMOVAL))
                return 0;

        return cma_notify_user(id_priv, RDMA_CM_EVENT_DEVICE_REMOVAL,
                               0, NULL, 0);
}

static void cma_process_remove(struct cma_device *cma_dev)
{
        struct list_head remove_list;
        struct rdma_id_private *id_priv;
        int ret;

        INIT_LIST_HEAD(&remove_list);

        mutex_lock(&lock);
        while (!list_empty(&cma_dev->id_list)) {
                id_priv = list_entry(cma_dev->id_list.next,
                                     struct rdma_id_private, list);

                if (cma_internal_listen(id_priv)) {
                        cma_destroy_listen(id_priv);
                        continue;
                }

                list_del(&id_priv->list);
                list_add_tail(&id_priv->list, &remove_list);
                atomic_inc(&id_priv->refcount);
                mutex_unlock(&lock);

                ret = cma_remove_id_dev(id_priv);
                cma_deref_id(id_priv);
                if (ret)
                        rdma_destroy_id(&id_priv->id);

                mutex_lock(&lock);
        }
        mutex_unlock(&lock);

        cma_deref_dev(cma_dev);
        wait_for_completion(&cma_dev->comp);
}

static void cma_remove_one(struct ib_device *device)
{
        struct cma_device *cma_dev;

        cma_dev = ib_get_client_data(device, &cma_client);
        if (!cma_dev)
                return;

        mutex_lock(&lock);
        list_del(&cma_dev->list);
        mutex_unlock(&lock);

        cma_process_remove(cma_dev);
        kfree(cma_dev);
}

static int cma_init(void)
{
        int ret;

        cma_wq = create_singlethread_workqueue("rdma_cm_wq");
        if (!cma_wq)
                return -ENOMEM;

        ret = ib_register_client(&cma_client);
        if (ret)
                goto err;
        return 0;

err:
        destroy_workqueue(cma_wq);
        return ret;
}

static void cma_cleanup(void)
{
        ib_unregister_client(&cma_client);
        destroy_workqueue(cma_wq);
        idr_destroy(&sdp_ps);
        idr_destroy(&tcp_ps);
}

module_init(cma_init);
module_exit(cma_cleanup);