/*
 * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

FILE_LICENCE ( GPL2_OR_LATER );

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <byteswap.h>
#include <errno.h>
#include <assert.h>
#include <gpxe/list.h>
#include <gpxe/errortab.h>
#include <gpxe/if_arp.h>
#include <gpxe/netdevice.h>
#include <gpxe/iobuf.h>
#include <gpxe/ipoib.h>
#include <gpxe/process.h>
#include <gpxe/infiniband.h>
#include <gpxe/ib_mi.h>
#include <gpxe/ib_sma.h>

/** @file
 *
 * Infiniband protocol
 *
 */

/** List of Infiniband devices */
struct list_head ib_devices = LIST_HEAD_INIT ( ib_devices );

/** List of open Infiniband devices, in reverse order of opening */
static struct list_head open_ib_devices = LIST_HEAD_INIT ( open_ib_devices );

/* Disambiguate the various possible EINPROGRESSes */
#define EINPROGRESS_INIT ( EINPROGRESS | EUNIQ_01 )
#define EINPROGRESS_ARMED ( EINPROGRESS | EUNIQ_02 )

/** Human-readable message for the link statuses */
struct errortab infiniband_errors[] __errortab = {
        { EINPROGRESS_INIT, "Initialising" },
        { EINPROGRESS_ARMED, "Armed" },
};

/***************************************************************************
 *
 * Completion queues
 *
 ***************************************************************************
 */

/**
 * Create completion queue
 *
 * @v ibdev             Infiniband device
 * @v num_cqes          Number of completion queue entries
 * @v op                Completion queue operations
 * @ret cq              New completion queue
 */
struct ib_completion_queue *
ib_create_cq ( struct ib_device *ibdev, unsigned int num_cqes,
               struct ib_completion_queue_operations *op ) {
        struct ib_completion_queue *cq;
        int rc;

        DBGC ( ibdev, "IBDEV %p creating completion queue\n", ibdev );

        /* Allocate and initialise data structure */
        cq = zalloc ( sizeof ( *cq ) );
        if ( ! cq )
                goto err_alloc_cq;
        cq->ibdev = ibdev;
        list_add ( &cq->list, &ibdev->cqs );
        cq->num_cqes = num_cqes;
        INIT_LIST_HEAD ( &cq->work_queues );
        cq->op = op;

        /* Perform device-specific initialisation and get CQN */
        if ( ( rc = ibdev->op->create_cq ( ibdev, cq ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not initialise completion "
                       "queue: %s\n", ibdev, strerror ( rc ) );
                goto err_dev_create_cq;
        }

        DBGC ( ibdev, "IBDEV %p created %d-entry completion queue %p (%p) "
               "with CQN %#lx\n", ibdev, num_cqes, cq,
               ib_cq_get_drvdata ( cq ), cq->cqn );
        return cq;

        ibdev->op->destroy_cq ( ibdev, cq );
 err_dev_create_cq:
        list_del ( &cq->list );
        free ( cq );
 err_alloc_cq:
        return NULL;
}

/**
 * Destroy completion queue
 *
 * @v ibdev             Infiniband device
 * @v cq                Completion queue
 */
void ib_destroy_cq ( struct ib_device *ibdev,
                     struct ib_completion_queue *cq ) {
        DBGC ( ibdev, "IBDEV %p destroying completion queue %#lx\n",
               ibdev, cq->cqn );
        assert ( list_empty ( &cq->work_queues ) );
        ibdev->op->destroy_cq ( ibdev, cq );
        list_del ( &cq->list );
        free ( cq );
}

/**
 * Poll completion queue
 *
 * @v ibdev             Infiniband device
 * @v cq                Completion queue
 */
void ib_poll_cq ( struct ib_device *ibdev,
                  struct ib_completion_queue *cq ) {
        struct ib_work_queue *wq;

        /* Poll completion queue */
        ibdev->op->poll_cq ( ibdev, cq );

        /* Refill receive work queues */
        list_for_each_entry ( wq, &cq->work_queues, list ) {
                if ( ! wq->is_send )
                        ib_refill_recv ( ibdev, wq->qp );
        }
}

/***************************************************************************
 *
 * Work queues
 *
 ***************************************************************************
 */

/**
 * Create queue pair
 *
 * @v ibdev             Infiniband device
 * @v type              Queue pair type
 * @v num_send_wqes     Number of send work queue entries
 * @v send_cq           Send completion queue
 * @v num_recv_wqes     Number of receive work queue entries
 * @v recv_cq           Receive completion queue
 * @ret qp              Queue pair
 *
 * The queue pair will be left in the INIT state; you must call
 * ib_modify_qp() before it is ready to use for sending and receiving.
 */
struct ib_queue_pair * ib_create_qp ( struct ib_device *ibdev,
                                      enum ib_queue_pair_type type,
                                      unsigned int num_send_wqes,
                                      struct ib_completion_queue *send_cq,
                                      unsigned int num_recv_wqes,
                                      struct ib_completion_queue *recv_cq ) {
        struct ib_queue_pair *qp;
        size_t total_size;
        int rc;

        DBGC ( ibdev, "IBDEV %p creating queue pair\n", ibdev );

        /* Allocate and initialise data structure */
        total_size = ( sizeof ( *qp ) +
                       ( num_send_wqes * sizeof ( qp->send.iobufs[0] ) ) +
                       ( num_recv_wqes * sizeof ( qp->recv.iobufs[0] ) ) );
        qp = zalloc ( total_size );
        if ( ! qp )
                goto err_alloc_qp;
        qp->ibdev = ibdev;
        list_add ( &qp->list, &ibdev->qps );
        qp->type = type;
        qp->send.qp = qp;
        qp->send.is_send = 1;
        qp->send.cq = send_cq;
        list_add ( &qp->send.list, &send_cq->work_queues );
        qp->send.psn = ( random() & 0xffffffUL );
        qp->send.num_wqes = num_send_wqes;
        qp->send.iobufs = ( ( ( void * ) qp ) + sizeof ( *qp ) );
        qp->recv.qp = qp;
        qp->recv.cq = recv_cq;
        list_add ( &qp->recv.list, &recv_cq->work_queues );
        qp->recv.psn = ( random() & 0xffffffUL );
        qp->recv.num_wqes = num_recv_wqes;
        qp->recv.iobufs = ( ( ( void * ) qp ) + sizeof ( *qp ) +
                            ( num_send_wqes * sizeof ( qp->send.iobufs[0] ) ));
        INIT_LIST_HEAD ( &qp->mgids );

        /* Perform device-specific initialisation and get QPN */
        if ( ( rc = ibdev->op->create_qp ( ibdev, qp ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not initialise queue pair: "
                       "%s\n", ibdev, strerror ( rc ) );
                goto err_dev_create_qp;
        }
        DBGC ( ibdev, "IBDEV %p created queue pair %p (%p) with QPN %#lx\n",
               ibdev, qp, ib_qp_get_drvdata ( qp ), qp->qpn );
        DBGC ( ibdev, "IBDEV %p QPN %#lx has %d send entries at [%p,%p)\n",
               ibdev, qp->qpn, num_send_wqes, qp->send.iobufs,
               qp->recv.iobufs );
        DBGC ( ibdev, "IBDEV %p QPN %#lx has %d receive entries at [%p,%p)\n",
               ibdev, qp->qpn, num_recv_wqes, qp->recv.iobufs,
               ( ( ( void * ) qp ) + total_size ) );

        /* Calculate externally-visible QPN */
        switch ( type ) {
        case IB_QPT_SMI:
                qp->ext_qpn = IB_QPN_SMI;
                break;
        case IB_QPT_GSI:
                qp->ext_qpn = IB_QPN_GSI;
                break;
        default:
                qp->ext_qpn = qp->qpn;
                break;
        }
        if ( qp->ext_qpn != qp->qpn ) {
                DBGC ( ibdev, "IBDEV %p QPN %#lx has external QPN %#lx\n",
                       ibdev, qp->qpn, qp->ext_qpn );
        }

        return qp;

        ibdev->op->destroy_qp ( ibdev, qp );
 err_dev_create_qp:
        list_del ( &qp->send.list );
        list_del ( &qp->recv.list );
        list_del ( &qp->list );
        free ( qp );
 err_alloc_qp:
        return NULL;
}

/**
 * Modify queue pair
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v av                New address vector, if applicable
 * @ret rc              Return status code
 */
int ib_modify_qp ( struct ib_device *ibdev, struct ib_queue_pair *qp ) {
        int rc;

        DBGC ( ibdev, "IBDEV %p modifying QPN %#lx\n", ibdev, qp->qpn );

        if ( ( rc = ibdev->op->modify_qp ( ibdev, qp ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not modify QPN %#lx: %s\n",
                       ibdev, qp->qpn, strerror ( rc ) );
                return rc;
        }

        return 0;
}

/**
 * Destroy queue pair
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 */
void ib_destroy_qp ( struct ib_device *ibdev, struct ib_queue_pair *qp ) {
        struct io_buffer *iobuf;
        unsigned int i;

        DBGC ( ibdev, "IBDEV %p destroying QPN %#lx\n",
               ibdev, qp->qpn );

        assert ( list_empty ( &qp->mgids ) );

        /* Perform device-specific destruction */
        ibdev->op->destroy_qp ( ibdev, qp );

        /* Complete any remaining I/O buffers with errors */
        for ( i = 0 ; i < qp->send.num_wqes ; i++ ) {
                if ( ( iobuf = qp->send.iobufs[i] ) != NULL )
                        ib_complete_send ( ibdev, qp, iobuf, -ECANCELED );
        }
        for ( i = 0 ; i < qp->recv.num_wqes ; i++ ) {
                if ( ( iobuf = qp->recv.iobufs[i] ) != NULL ) {
                        ib_complete_recv ( ibdev, qp, NULL, iobuf,
                                           -ECANCELED );
                }
        }

        /* Remove work queues from completion queue */
        list_del ( &qp->send.list );
        list_del ( &qp->recv.list );

        /* Free QP */
        list_del ( &qp->list );
        free ( qp );
}

/**
 * Find queue pair by QPN
 *
 * @v ibdev             Infiniband device
 * @v qpn               Queue pair number
 * @ret qp              Queue pair, or NULL
 */
struct ib_queue_pair * ib_find_qp_qpn ( struct ib_device *ibdev,
                                        unsigned long qpn ) {
        struct ib_queue_pair *qp;

        list_for_each_entry ( qp, &ibdev->qps, list ) {
                if ( ( qpn == qp->qpn ) || ( qpn == qp->ext_qpn ) )
                        return qp;
        }
        return NULL;
}

/**
 * Find queue pair by multicast GID
 *
 * @v ibdev             Infiniband device
 * @v gid               Multicast GID
 * @ret qp              Queue pair, or NULL
 */
struct ib_queue_pair * ib_find_qp_mgid ( struct ib_device *ibdev,
                                         struct ib_gid *gid ) {
        struct ib_queue_pair *qp;
        struct ib_multicast_gid *mgid;

        list_for_each_entry ( qp, &ibdev->qps, list ) {
                list_for_each_entry ( mgid, &qp->mgids, list ) {
                        if ( memcmp ( &mgid->gid, gid,
                                      sizeof ( mgid->gid ) ) == 0 ) {
                                return qp;
                        }
                }
        }
        return NULL;
}

/**
 * Find work queue belonging to completion queue
 *
 * @v cq                Completion queue
 * @v qpn               Queue pair number
 * @v is_send           Find send work queue (rather than receive)
 * @ret wq              Work queue, or NULL if not found
 */
struct ib_work_queue * ib_find_wq ( struct ib_completion_queue *cq,
                                    unsigned long qpn, int is_send ) {
        struct ib_work_queue *wq;

        list_for_each_entry ( wq, &cq->work_queues, list ) {
                if ( ( wq->qp->qpn == qpn ) && ( wq->is_send == is_send ) )
                        return wq;
        }
        return NULL;
}

/**
 * Post send work queue entry
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v av                Address vector
 * @v iobuf             I/O buffer
 * @ret rc              Return status code
 */
int ib_post_send ( struct ib_device *ibdev, struct ib_queue_pair *qp,
                   struct ib_address_vector *av,
                   struct io_buffer *iobuf ) {
        struct ib_address_vector av_copy;
        int rc;

        /* Check queue fill level */
        if ( qp->send.fill >= qp->send.num_wqes ) {
                DBGC ( ibdev, "IBDEV %p QPN %#lx send queue full\n",
                       ibdev, qp->qpn );
                return -ENOBUFS;
        }

        /* Use default address vector if none specified */
        if ( ! av )
                av = &qp->av;

        /* Make modifiable copy of address vector */
        memcpy ( &av_copy, av, sizeof ( av_copy ) );
        av = &av_copy;

        /* Fill in optional parameters in address vector */
        if ( ! av->qkey )
                av->qkey = qp->qkey;
        if ( ! av->rate )
                av->rate = IB_RATE_2_5;

        /* Post to hardware */
        if ( ( rc = ibdev->op->post_send ( ibdev, qp, av, iobuf ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p QPN %#lx could not post send WQE: "
                       "%s\n", ibdev, qp->qpn, strerror ( rc ) );
                return rc;
        }

        qp->send.fill++;
        return 0;
}

/**
 * Post receive work queue entry
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v iobuf             I/O buffer
 * @ret rc              Return status code
 */
int ib_post_recv ( struct ib_device *ibdev, struct ib_queue_pair *qp,
                   struct io_buffer *iobuf ) {
        int rc;

        /* Check packet length */
        if ( iob_tailroom ( iobuf ) < IB_MAX_PAYLOAD_SIZE ) {
                DBGC ( ibdev, "IBDEV %p QPN %#lx wrong RX buffer size (%zd)\n",
                       ibdev, qp->qpn, iob_tailroom ( iobuf ) );
                return -EINVAL;
        }

        /* Check queue fill level */
        if ( qp->recv.fill >= qp->recv.num_wqes ) {
                DBGC ( ibdev, "IBDEV %p QPN %#lx receive queue full\n",
                       ibdev, qp->qpn );
                return -ENOBUFS;
        }

        /* Post to hardware */
        if ( ( rc = ibdev->op->post_recv ( ibdev, qp, iobuf ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p QPN %#lx could not post receive WQE: "
                       "%s\n", ibdev, qp->qpn, strerror ( rc ) );
                return rc;
        }

        qp->recv.fill++;
        return 0;
}

/**
 * Complete send work queue entry
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v iobuf             I/O buffer
 * @v rc                Completion status code
 */
void ib_complete_send ( struct ib_device *ibdev, struct ib_queue_pair *qp,
                        struct io_buffer *iobuf, int rc ) {

        if ( qp->send.cq->op->complete_send ) {
                qp->send.cq->op->complete_send ( ibdev, qp, iobuf, rc );
        } else {
                free_iob ( iobuf );
        }
        qp->send.fill--;
}

/**
 * Complete receive work queue entry
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v av                Address vector
 * @v iobuf             I/O buffer
 * @v rc                Completion status code
 */
void ib_complete_recv ( struct ib_device *ibdev, struct ib_queue_pair *qp,
                        struct ib_address_vector *av,
                        struct io_buffer *iobuf, int rc ) {

        if ( qp->recv.cq->op->complete_recv ) {
                qp->recv.cq->op->complete_recv ( ibdev, qp, av, iobuf, rc );
        } else {
                free_iob ( iobuf );
        }
        qp->recv.fill--;
}

/**
 * Refill receive work queue
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 */
void ib_refill_recv ( struct ib_device *ibdev, struct ib_queue_pair *qp ) {
        struct io_buffer *iobuf;
        int rc;

        /* Keep filling while unfilled entries remain */
        while ( qp->recv.fill < qp->recv.num_wqes ) {

                /* Allocate I/O buffer */
                iobuf = alloc_iob ( IB_MAX_PAYLOAD_SIZE );
                if ( ! iobuf ) {
                        /* Non-fatal; we will refill on next attempt */
                        return;
                }

                /* Post I/O buffer */
                if ( ( rc = ib_post_recv ( ibdev, qp, iobuf ) ) != 0 ) {
                        DBGC ( ibdev, "IBDEV %p could not refill: %s\n",
                               ibdev, strerror ( rc ) );
                        free_iob ( iobuf );
                        /* Give up */
                        return;
                }
        }
}

/***************************************************************************
 *
 * Link control
 *
 ***************************************************************************
 */

/**
 * Open port
 *
 * @v ibdev             Infiniband device
 * @ret rc              Return status code
 */
int ib_open ( struct ib_device *ibdev ) {
        int rc;

        /* Increment device open request counter */
        if ( ibdev->open_count++ > 0 ) {
                /* Device was already open; do nothing */
                return 0;
        }

        /* Create subnet management interface */
        ibdev->smi = ib_create_mi ( ibdev, IB_QPT_SMI );
        if ( ! ibdev->smi ) {
                DBGC ( ibdev, "IBDEV %p could not create SMI\n", ibdev );
                rc = -ENOMEM;
                goto err_create_smi;
        }

        /* Create subnet management agent */
        if ( ( rc = ib_create_sma ( ibdev, ibdev->smi ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not create SMA: %s\n",
                       ibdev, strerror ( rc ) );
                goto err_create_sma;
        }

        /* Create general services interface */
        ibdev->gsi = ib_create_mi ( ibdev, IB_QPT_GSI );
        if ( ! ibdev->gsi ) {
                DBGC ( ibdev, "IBDEV %p could not create GSI\n", ibdev );
                rc = -ENOMEM;
                goto err_create_gsi;
        }

        /* Open device */
        if ( ( rc = ibdev->op->open ( ibdev ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not open: %s\n",
                       ibdev, strerror ( rc ) );
                goto err_open;
        }

        /* Add to head of open devices list */
        list_add ( &ibdev->open_list, &open_ib_devices );

        assert ( ibdev->open_count == 1 );
        return 0;

        ibdev->op->close ( ibdev );
 err_open:
        ib_destroy_mi ( ibdev, ibdev->gsi );
 err_create_gsi:
        ib_destroy_sma ( ibdev, ibdev->smi );
 err_create_sma:
        ib_destroy_mi ( ibdev, ibdev->smi );
 err_create_smi:
        assert ( ibdev->open_count == 1 );
        ibdev->open_count = 0;
        return rc;
}

/**
 * Close port
 *
 * @v ibdev             Infiniband device
 */
void ib_close ( struct ib_device *ibdev ) {

        /* Decrement device open request counter */
        ibdev->open_count--;

        /* Close device if this was the last remaining requested opening */
        if ( ibdev->open_count == 0 ) {
                list_del ( &ibdev->open_list );
                ib_destroy_mi ( ibdev, ibdev->gsi );
                ib_destroy_sma ( ibdev, ibdev->smi );
                ib_destroy_mi ( ibdev, ibdev->smi );
                ibdev->op->close ( ibdev );
        }
}

/**
 * Get link state
 *
 * @v ibdev             Infiniband device
 * @ret rc              Link status code
 */
int ib_link_rc ( struct ib_device *ibdev ) {
        switch ( ibdev->port_state ) {
        case IB_PORT_STATE_DOWN:        return -ENOTCONN;
        case IB_PORT_STATE_INIT:        return -EINPROGRESS_INIT;
        case IB_PORT_STATE_ARMED:       return -EINPROGRESS_ARMED;
        case IB_PORT_STATE_ACTIVE:      return 0;
        default:                        return -EINVAL;
        }
}

/***************************************************************************
 *
 * Multicast
 *
 ***************************************************************************
 */

/**
 * Attach to multicast group
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v gid               Multicast GID
 * @ret rc              Return status code
 *
 * Note that this function handles only the local device's attachment
 * to the multicast GID; it does not issue the relevant MADs to join
 * the multicast group on the subnet.
 */
int ib_mcast_attach ( struct ib_device *ibdev, struct ib_queue_pair *qp,
                      struct ib_gid *gid ) {
        struct ib_multicast_gid *mgid;
        int rc;

        /* Add to software multicast GID list */
        mgid = zalloc ( sizeof ( *mgid ) );
        if ( ! mgid ) {
                rc = -ENOMEM;
                goto err_alloc_mgid;
        }
        memcpy ( &mgid->gid, gid, sizeof ( mgid->gid ) );
        list_add ( &mgid->list, &qp->mgids );

        /* Add to hardware multicast GID list */
        if ( ( rc = ibdev->op->mcast_attach ( ibdev, qp, gid ) ) != 0 )
                goto err_dev_mcast_attach;

        return 0;

 err_dev_mcast_attach:
        list_del ( &mgid->list );
        free ( mgid );
 err_alloc_mgid:
        return rc;
}

/**
 * Detach from multicast group
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v gid               Multicast GID
 */
void ib_mcast_detach ( struct ib_device *ibdev, struct ib_queue_pair *qp,
                       struct ib_gid *gid ) {
        struct ib_multicast_gid *mgid;

        /* Remove from hardware multicast GID list */
        ibdev->op->mcast_detach ( ibdev, qp, gid );

        /* Remove from software multicast GID list */
        list_for_each_entry ( mgid, &qp->mgids, list ) {
                if ( memcmp ( &mgid->gid, gid, sizeof ( mgid->gid ) ) == 0 ) {
                        list_del ( &mgid->list );
                        free ( mgid );
                        break;
                }
        }
}

/***************************************************************************
 *
 * Miscellaneous
 *
 ***************************************************************************
 */

/**
 * Get Infiniband HCA information
 *
 * @v ibdev             Infiniband device
 * @ret hca_guid        HCA GUID
 * @ret num_ports       Number of ports
 */
int ib_get_hca_info ( struct ib_device *ibdev,
                      struct ib_gid_half *hca_guid ) {
        struct ib_device *tmp;
        int num_ports = 0;

        /* Search for IB devices with the same physical device to
         * identify port count and a suitable Node GUID.
         */
        for_each_ibdev ( tmp ) {
                if ( tmp->dev != ibdev->dev )
                        continue;
                if ( num_ports == 0 ) {
                        memcpy ( hca_guid, &tmp->gid.u.half[1],
                                 sizeof ( *hca_guid ) );
                }
                num_ports++;
        }
        return num_ports;
}

/**
 * Set port information
 *
 * @v ibdev             Infiniband device
 * @v mad               Set port information MAD
 */
int ib_set_port_info ( struct ib_device *ibdev, union ib_mad *mad ) {
        int rc;

        /* Adapters with embedded SMAs do not need to support this method */
        if ( ! ibdev->op->set_port_info ) {
                DBGC ( ibdev, "IBDEV %p does not support setting port "
                       "information\n", ibdev );
                return -ENOTSUP;
        }

        if ( ( rc = ibdev->op->set_port_info ( ibdev, mad ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not set port information: %s\n",
                       ibdev, strerror ( rc ) );
                return rc;
        }

        return 0;
};

/**
 * Set partition key table
 *
 * @v ibdev             Infiniband device
 * @v mad               Set partition key table MAD
 */
int ib_set_pkey_table ( struct ib_device *ibdev, union ib_mad *mad ) {
        int rc;

        /* Adapters with embedded SMAs do not need to support this method */
        if ( ! ibdev->op->set_pkey_table ) {
                DBGC ( ibdev, "IBDEV %p does not support setting partition "
                       "key table\n", ibdev );
                return -ENOTSUP;
        }

        if ( ( rc = ibdev->op->set_pkey_table ( ibdev, mad ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not set partition key table: "
                       "%s\n", ibdev, strerror ( rc ) );
                return rc;
        }

        return 0;
};

/***************************************************************************
 *
 * Event queues
 *
 ***************************************************************************
 */

/**
 * Handle Infiniband link state change
 *
 * @v ibdev             Infiniband device
 */
void ib_link_state_changed ( struct ib_device *ibdev ) {

        /* Notify IPoIB of link state change */
        ipoib_link_state_changed ( ibdev );
}

/**
 * Poll event queue
 *
 * @v ibdev             Infiniband device
 */
void ib_poll_eq ( struct ib_device *ibdev ) {
        struct ib_completion_queue *cq;

        /* Poll device's event queue */
        ibdev->op->poll_eq ( ibdev );

        /* Poll all completion queues */
        list_for_each_entry ( cq, &ibdev->cqs, list )
                ib_poll_cq ( ibdev, cq );
}

/**
 * Single-step the Infiniband event queue
 *
 * @v process           Infiniband event queue process
 */
static void ib_step ( struct process *process __unused ) {
        struct ib_device *ibdev;

        for_each_ibdev ( ibdev )
                ib_poll_eq ( ibdev );
}

/** Infiniband event queue process */
struct process ib_process __permanent_process = {
        .list = LIST_HEAD_INIT ( ib_process.list ),
        .step = ib_step,
};

/***************************************************************************
 *
 * Infiniband device creation/destruction
 *
 ***************************************************************************
 */

/**
 * Allocate Infiniband device
 *
 * @v priv_size         Size of driver private data area
 * @ret ibdev           Infiniband device, or NULL
 */
struct ib_device * alloc_ibdev ( size_t priv_size ) {
        struct ib_device *ibdev;
        void *drv_priv;
        size_t total_len;

        total_len = ( sizeof ( *ibdev ) + priv_size );
        ibdev = zalloc ( total_len );
        if ( ibdev ) {
                drv_priv = ( ( ( void * ) ibdev ) + sizeof ( *ibdev ) );
                ib_set_drvdata ( ibdev, drv_priv );
                INIT_LIST_HEAD ( &ibdev->cqs );
                INIT_LIST_HEAD ( &ibdev->qps );
                ibdev->port_state = IB_PORT_STATE_DOWN;
                ibdev->lid = IB_LID_NONE;
                ibdev->pkey = IB_PKEY_DEFAULT;
        }
        return ibdev;
}

/**
 * Register Infiniband device
 *
 * @v ibdev             Infiniband device
 * @ret rc              Return status code
 */
int register_ibdev ( struct ib_device *ibdev ) {
        int rc;

        /* Add to device list */
        ibdev_get ( ibdev );
        list_add_tail ( &ibdev->list, &ib_devices );

        /* Add IPoIB device */
        if ( ( rc = ipoib_probe ( ibdev ) ) != 0 ) {
                DBGC ( ibdev, "IBDEV %p could not add IPoIB device: %s\n",
                       ibdev, strerror ( rc ) );
                goto err_ipoib_probe;
        }

        DBGC ( ibdev, "IBDEV %p registered (phys %s)\n", ibdev,
               ibdev->dev->name );
        return 0;

 err_ipoib_probe:
        list_del ( &ibdev->list );
        ibdev_put ( ibdev );
        return rc;
}

/**
 * Unregister Infiniband device
 *
 * @v ibdev             Infiniband device
 */
void unregister_ibdev ( struct ib_device *ibdev ) {

        /* Close device */
        ipoib_remove ( ibdev );

        /* Remove from device list */
        list_del ( &ibdev->list );
        ibdev_put ( ibdev );
        DBGC ( ibdev, "IBDEV %p unregistered\n", ibdev );
}

/**
 * Find Infiniband device by GID
 *
 * @v gid               GID
 * @ret ibdev           Infiniband device, or NULL
 */
struct ib_device * find_ibdev ( struct ib_gid *gid ) {
        struct ib_device *ibdev;

        for_each_ibdev ( ibdev ) {
                if ( memcmp ( gid, &ibdev->gid, sizeof ( *gid ) ) == 0 )
                        return ibdev;
        }
        return NULL;
}

/**
 * Get most recently opened Infiniband device
 *
 * @ret ibdev           Most recently opened Infiniband device, or NULL
 */
struct ib_device * last_opened_ibdev ( void ) {
        struct ib_device *ibdev;

        list_for_each_entry ( ibdev, &open_ib_devices, open_list ) {
                assert ( ibdev->open_count != 0 );
                return ibdev;
        }

        return NULL;
}