fcels.c

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/*
 * Copyright (C) 2010 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., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 * You can also choose to distribute this program under the terms of
 * the Unmodified Binary Distribution Licence (as given in the file
 * COPYING.UBDL), provided that you have satisfied its requirements.
 */
 
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <byteswap.h>
#include <ipxe/interface.h>
#include <ipxe/xfer.h>
#include <ipxe/iobuf.h>
#include <ipxe/process.h>
#include <ipxe/fc.h>
#include <ipxe/fcels.h>
 
/** @file
 *
 * Fibre Channel Extended Link Services
 *
 */
 
/** Fibre Channel ELS transaction debug message format */
#define FCELS_FMT "FCELS %s %s %s %s"
 
/** Fibre Channel ELS transaction debug message arguments */
#define FCELS_ARGS( els )                                               \
        (els)->port->name,                                              \
        ( (els)->handler ? (els)->handler->name : "unknown ELS" ),      \
        ( fc_els_is_request ( els ) ? "to" : "from" ),                  \
        fc_id_ntoa ( &(els)->peer_port_id )
 
struct fc_els_handler fc_els_unknown_handler __fc_els_handler;
 
/**
 * Free Fibre Channel ELS transaction
 *
 * @v refcnt            Reference count
 */
static void fc_els_free ( struct refcnt *refcnt ) {
        struct fc_els *els = container_of ( refcnt, struct fc_els, refcnt );
 
        assert ( ! process_running ( &els->process ) );
        fc_port_put ( els->port );
        free ( els );
}
 
/**
 * Close Fibre Channel ELS transaction
 *
 * @v els               Fibre Channel ELS transaction
 * @v rc                Reason for close
 */
static void fc_els_close ( struct fc_els *els, int rc ) {
 
        if ( rc != 0 ) {
                DBGC ( els, FCELS_FMT " complete (%s)\n",
                       FCELS_ARGS ( els ), strerror ( rc ) );
        }
 
        /* Stop process */
        process_del ( &els->process );
 
        /* Shut down interfaces */
        intf_shutdown ( &els->xchg, rc );
        intf_shutdown ( &els->job, rc );
}
 
/**
 * Detect Fibre Channel ELS frame handler
 *
 * @v els               Fibre Channel ELS transaction
 * @v command           ELS command code
 * @ret handler         ELS handler, or NULL
 */
static struct fc_els_handler * fc_els_detect ( struct fc_els *els,
                                               const void *data,
                                               size_t len ) {
        const struct fc_els_frame_common *frame = data;
        struct fc_els_handler *handler;
        int rc;
 
        /* Sanity check */
        if ( len < sizeof ( *frame ) )
                return NULL;
 
        /* Try each handler in turn */
        for_each_table_entry ( handler, FC_ELS_HANDLERS ) {
                if ( ( rc = handler->detect ( els, data, len ) ) == 0 )
                        return handler;
        }
 
        return NULL;
}
 
/**
 * Transmit Fibre Channel ELS frame
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              Data to transmit
 * @v len               Length of data
 * @ret rc              Return status code
 */
int fc_els_tx ( struct fc_els *els, const void *data, size_t len ) {
        struct xfer_metadata meta;
        struct sockaddr_fc dest;
        int rc;
 
        DBGC2 ( els, FCELS_FMT " transmitting:\n", FCELS_ARGS ( els ) );
        DBGC2_HDA ( els, 0, data, len );
 
        /* Construct metadata */
        memset ( &meta, 0, sizeof ( meta ) );
        meta.flags = ( fc_els_is_request ( els ) ?
                       XFER_FL_OVER : ( XFER_FL_RESPONSE | XFER_FL_OUT ) );
        meta.dest = fc_fill_sockaddr ( &dest, &els->peer_port_id );
 
        /* Transmit frame */
        if ( ( rc = xfer_deliver_raw_meta ( &els->xchg, data, len,
                                            &meta ) ) != 0 ) {
                DBGC ( els, FCELS_FMT " could not deliver frame: %s\n",
                       FCELS_ARGS ( els ), strerror ( rc ) );
                return rc;
        }
 
        return 0;
}
 
/**
 * Receive Fibre Channel ELS frame
 *
 * @v els               Fibre Channel ELS transaction
 * @v iobuf             I/O buffer
 * @v meta              Data transfer metadata
 * @ret rc              Return status code
 */
static int fc_els_rx ( struct fc_els *els,
                       struct io_buffer *iobuf,
                       struct xfer_metadata *meta ) {
        struct sockaddr_fc *src = ( ( struct sockaddr_fc * ) meta->src );
        struct sockaddr_fc *dest = ( ( struct sockaddr_fc * ) meta->dest );
        struct fc_els_frame_common *frame;
        size_t len = iob_len ( iobuf );
        int rc;
 
        /* Sanity check */
        if ( len < sizeof ( *frame ) ) {
                DBGC ( els, FCELS_FMT " received underlength frame:\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, iobuf->data, len );
                rc = -EINVAL;
                goto done;
        }
        frame = iobuf->data;
        if ( ! src ) {
                DBGC ( els, FCELS_FMT " received frame missing source "
                       "address:\n", FCELS_ARGS ( els ) );
                rc = -EINVAL;
                goto done;
        }
        if ( ! dest ) {
                DBGC ( els, FCELS_FMT " received frame missing destination "
                       "address:\n", FCELS_ARGS ( els ) );
                rc = -EINVAL;
                goto done;
        }
 
        /* Check for rejection responses */
        if ( fc_els_is_request ( els ) &&
             ( frame->command != FC_ELS_LS_ACC ) ) {
                DBGC ( els, FCELS_FMT " rejected:\n", FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, frame, len );
                rc = -EACCES;
                goto done;
        }
 
        /* Update port IDs */
        memcpy ( &els->port_id, &dest->sfc_port_id, sizeof ( els->port_id ) );
        memcpy ( &els->peer_port_id, &src->sfc_port_id,
                 sizeof ( els->peer_port_id ) );
 
        /* Determine handler, if necessary */
        if ( ! els->handler )
                els->handler = fc_els_detect ( els, frame, len );
        if ( ! els->handler )
                els->handler = &fc_els_unknown_handler;
 
        DBGC2 ( els, FCELS_FMT " received:\n", FCELS_ARGS ( els ) );
        DBGC2_HDA ( els, 0, frame, len );
 
        /* Handle received frame */
        if ( ( rc = els->handler->rx ( els, frame, len ) ) != 0 ) {
                DBGC ( els, FCELS_FMT " could not handle received frame: "
                       "%s\n", FCELS_ARGS ( els ), strerror ( rc ) );
                DBGC_HDA ( els, 0, frame, len );
                goto done;
        }
 
 done:
        /* Free I/O buffer */
        free_iob ( iobuf );
 
        /* Close transaction */
        fc_els_close ( els, rc );
 
        return rc;
}
 
/** Fibre Channel ELS exchange interface operations */
static struct interface_operation fc_els_xchg_op[] = {
        INTF_OP ( xfer_deliver, struct fc_els *, fc_els_rx ),
        INTF_OP ( intf_close, struct fc_els *, fc_els_close ),
};
 
/** Fibre Channel ELS exchange interface descriptor */
static struct interface_descriptor fc_els_xchg_desc =
        INTF_DESC ( struct fc_els, xchg, fc_els_xchg_op );
 
/** Fibre Channel ELS job control interface operations */
static struct interface_operation fc_els_job_op[] = {
        INTF_OP ( intf_close, struct fc_els *, fc_els_close ),
};
 
/** Fibre Channel ELS job control interface descriptor */
static struct interface_descriptor fc_els_job_desc =
        INTF_DESC ( struct fc_els, job, fc_els_job_op );
 
/**
 * Fibre Channel ELS process
 *
 * @v els               Fibre Channel ELS transaction
 */
static void fc_els_step ( struct fc_els *els ) {
        int xchg_id;
        int rc;
 
        /* Sanity check */
        assert ( fc_els_is_request ( els ) );
 
        /* Create exchange */
        if ( ( xchg_id = fc_xchg_originate ( &els->xchg, els->port,
                                             &els->peer_port_id,
                                             FC_TYPE_ELS ) ) < 0 ) {
                rc = xchg_id;
                DBGC ( els, FCELS_FMT " could not create exchange: %s\n",
                       FCELS_ARGS ( els ), strerror ( rc ) );
                fc_els_close ( els, rc );
                return;
        }
 
        /* Transmit request */
        if ( ( rc = els->handler->tx ( els ) ) != 0 ) {
                DBGC ( els, FCELS_FMT " could not transmit request: %s\n",
                       FCELS_ARGS ( els ), strerror ( rc ) );
                fc_els_close ( els, rc );
                return;
        }
}
 
/** Fibre Channel ELS process descriptor */
static struct process_descriptor fc_els_process_desc =
        PROC_DESC_ONCE ( struct fc_els, process, fc_els_step );
 
/**
 * Create ELS transaction
 *
 * @v port              Fibre Channel port
 * @v port_id           Local port ID
 * @v peer_port_id      Peer port ID
 * @ret els             Fibre Channel ELS transaction, or NULL
 */
static struct fc_els * fc_els_create ( struct fc_port *port,
                                       struct fc_port_id *port_id,
                                       struct fc_port_id *peer_port_id ) {
        struct fc_els *els;
 
        /* Allocate and initialise structure */
        els = zalloc ( sizeof ( *els ) );
        if ( ! els )
                return NULL;
        ref_init ( &els->refcnt, fc_els_free );
        intf_init ( &els->job, &fc_els_job_desc, &els->refcnt );
        intf_init ( &els->xchg, &fc_els_xchg_desc, &els->refcnt );
        process_init_stopped ( &els->process, &fc_els_process_desc,
                               &els->refcnt );
        els->port = fc_port_get ( port );
        memcpy ( &els->port_id, port_id, sizeof ( els->port_id ) );
        memcpy ( &els->peer_port_id, peer_port_id,
                 sizeof ( els->peer_port_id ) );
        return els;
}
 
/**
 * Create ELS request
 *
 * @v job               Parent job-control interface
 * @v port              Fibre Channel port
 * @v peer_port_id      Peer port ID
 * @v handler           ELS handler
 * @ret rc              Return status code
 */
int fc_els_request ( struct interface *job, struct fc_port *port,
                     struct fc_port_id *peer_port_id,
                     struct fc_els_handler *handler ) {
        struct fc_els *els;
 
        /* Allocate and initialise structure */
        els = fc_els_create ( port, &port->port_id, peer_port_id );
        if ( ! els )
                return -ENOMEM;
        els->handler = handler;
        els->flags = FC_ELS_REQUEST;
        process_add ( &els->process );
 
        /* Attach to parent job interface, mortalise self, and return */
        intf_plug_plug ( &els->job, job );
        ref_put ( &els->refcnt );
        return 0;
}
 
/**
 * Create ELS response
 *
 * @v xchg              Exchange interface
 * @v port              Fibre Channel port
 * @v port_id           Local port ID
 * @v peer_port_id      Peer port ID
 * @ret rc              Return status code
 */
static int fc_els_respond ( struct interface *xchg, struct fc_port *port,
                            struct fc_port_id *port_id,
                            struct fc_port_id *peer_port_id ) {
        struct fc_els *els;
 
        /* Allocate and initialise structure */
        els = fc_els_create ( port, port_id, peer_port_id );
        if ( ! els )
                return -ENOMEM;
 
        /* Attach to exchange interface, mortalise self, and return */
        intf_plug_plug ( &els->xchg, xchg );
        ref_put ( &els->refcnt );
        return 0;
}
 
/** Fibre Channel ELS responder */
struct fc_responder fc_els_responder __fc_responder = {
        .type = FC_TYPE_ELS,
        .respond = fc_els_respond,
};
 
/******************************************************************************
 *
 * Unknown ELS handler
 *
 ******************************************************************************
 */
 
/**
 * Transmit unknown ELS request
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_unknown_tx ( struct fc_els *els __unused ) {
        return -ENOTSUP;
}
 
/**
 * Transmit unknown ELS response
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_unknown_tx_response ( struct fc_els *els ) {
        struct fc_ls_rjt_frame ls_rjt;
 
        /* Construct LS_RJT */
        memset ( &ls_rjt, 0, sizeof ( ls_rjt ) );
        ls_rjt.command = FC_ELS_LS_RJT;
        ls_rjt.reason = FC_ELS_RJT_UNSUPPORTED;
 
        /* Transmit LS_RJT */
        return fc_els_tx ( els, &ls_rjt, sizeof ( ls_rjt ) );
}
 
/**
 * Receive unknown ELS
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_unknown_rx ( struct fc_els *els, void *data, size_t len ) {
        int rc;
 
        DBGC ( els, FCELS_FMT ":\n", FCELS_ARGS ( els ) );
        DBGC_HDA ( els, 0, data, len );
 
        /* Transmit response, if applicable */
        if ( ! fc_els_is_request ( els ) ) {
                if ( ( rc = fc_els_unknown_tx_response ( els ) ) != 0 )
                        return rc;
        }
 
        return 0;
}
 
/**
 * Detect unknown ELS
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_unknown_detect ( struct fc_els *els __unused,
                                   const void *data __unused,
                                   size_t len __unused ) {
        return -ENOTSUP;
}
 
/** Unknown ELS handler */
struct fc_els_handler fc_els_unknown_handler __fc_els_handler = {
        .name           = "UNKNOWN",
        .tx             = fc_els_unknown_tx,
        .rx             = fc_els_unknown_rx,
        .detect         = fc_els_unknown_detect,
};
 
/******************************************************************************
 *
 * FLOGI
 *
 ******************************************************************************
 */
 
/**
 * Transmit FLOGI
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_flogi_tx ( struct fc_els *els ) {
        struct fc_login_frame flogi;
 
        /* Construct FLOGI */
        memset ( &flogi, 0, sizeof ( flogi ) );
        flogi.command = fc_els_tx_command ( els, FC_ELS_FLOGI );
        flogi.common.version = htons ( FC_LOGIN_VERSION );
        flogi.common.credit = htons ( FC_LOGIN_DEFAULT_B2B );
        flogi.common.flags = htons ( FC_LOGIN_CONTINUOUS_OFFSET );
        flogi.common.mtu = htons ( FC_LOGIN_DEFAULT_MTU );
        memcpy ( &flogi.port_wwn, &els->port->port_wwn,
                 sizeof ( flogi.port_wwn ) );
        memcpy ( &flogi.node_wwn, &els->port->node_wwn,
                 sizeof ( flogi.node_wwn ) );
        flogi.class3.flags = htons ( FC_LOGIN_CLASS_VALID |
                                     FC_LOGIN_CLASS_SEQUENTIAL );
 
        /* Transmit FLOGI */
        return fc_els_tx ( els, &flogi, sizeof ( flogi ) );
}
 
/**
 * Receive FLOGI
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_flogi_rx ( struct fc_els *els, void *data, size_t len ) {
        struct fc_login_frame *flogi;
        int has_fabric;
        int rc;
 
        /* Sanity check */
        if ( len < sizeof ( *flogi ) ) {
                DBGC ( els, FCELS_FMT " received underlength frame:\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, data, len );
                return -EINVAL;
        }
        flogi = data;
 
        /* Extract parameters */
        has_fabric = ( flogi->common.flags & htons ( FC_LOGIN_F_PORT ) );
        DBGC ( els, FCELS_FMT " has node %s\n", FCELS_ARGS ( els ),
               fc_ntoa ( &flogi->node_wwn ) );
        DBGC ( els, FCELS_FMT " has port %s\n", FCELS_ARGS ( els ),
               fc_ntoa ( &flogi->port_wwn ) );
        if ( has_fabric ) {
                DBGC ( els, FCELS_FMT " has fabric with", FCELS_ARGS ( els ) );
                DBGC ( els, " local ID %s\n", fc_id_ntoa ( &els->port_id ) );
        } else {
                DBGC ( els, FCELS_FMT " has point-to-point link\n",
                       FCELS_ARGS ( els ) );
        }
 
        /* Log in port */
        if ( ( rc = fc_port_login ( els->port, &els->port_id, &flogi->node_wwn,
                                    &flogi->port_wwn, has_fabric ) ) != 0 ) {
                DBGC ( els, FCELS_FMT " could not log in port: %s\n",
                       FCELS_ARGS ( els ), strerror ( rc ) );
                return rc;
        }
 
        /* Send any responses to the newly-assigned peer port ID, if
         * applicable.
         */
        if ( ! has_fabric ) {
                memcpy ( &els->peer_port_id, &els->port->ptp_link_port_id,
                         sizeof ( els->peer_port_id ) );
        }
 
        /* Transmit response, if applicable */
        if ( ! fc_els_is_request ( els ) ) {
                if ( ( rc = fc_els_flogi_tx ( els ) ) != 0 )
                        return rc;
        }
 
        return 0;
}
 
/**
 * Detect FLOGI
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_flogi_detect ( struct fc_els *els __unused, const void *data,
                                 size_t len __unused ) {
        const struct fc_login_frame *flogi = data;
 
        /* Check for FLOGI */
        if ( flogi->command != FC_ELS_FLOGI )
                return -EINVAL;
 
        return 0;
}
 
/** FLOGI ELS handler */
struct fc_els_handler fc_els_flogi_handler __fc_els_handler = {
        .name           = "FLOGI",
        .tx             = fc_els_flogi_tx,
        .rx             = fc_els_flogi_rx,
        .detect         = fc_els_flogi_detect,
};
 
/**
 * Create FLOGI request
 *
 * @v parent            Parent interface
 * @v port              Fibre Channel port
 * @ret rc              Return status code
 */
int fc_els_flogi ( struct interface *parent, struct fc_port *port ) {
 
        return fc_els_request ( parent, port, &fc_f_port_id,
                                &fc_els_flogi_handler );
}
 
/******************************************************************************
 *
 * PLOGI
 *
 ******************************************************************************
 */
 
/**
 * Transmit PLOGI
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_plogi_tx ( struct fc_els *els ) {
        struct fc_login_frame plogi;
 
        /* Construct PLOGI */
        memset ( &plogi, 0, sizeof ( plogi ) );
        plogi.command = fc_els_tx_command ( els, FC_ELS_PLOGI );
        plogi.common.version = htons ( FC_LOGIN_VERSION );
        plogi.common.credit = htons ( FC_LOGIN_DEFAULT_B2B );
        plogi.common.flags = htons ( FC_LOGIN_CONTINUOUS_OFFSET );
        plogi.common.mtu = htons ( FC_LOGIN_DEFAULT_MTU );
        plogi.common.u.plogi.max_seq = htons ( FC_LOGIN_DEFAULT_MAX_SEQ );
        plogi.common.u.plogi.rel_offs = htons ( FC_LOGIN_DEFAULT_REL_OFFS );
        plogi.common.e_d_tov = htonl ( FC_LOGIN_DEFAULT_E_D_TOV );
        memcpy ( &plogi.port_wwn, &els->port->port_wwn,
                 sizeof ( plogi.port_wwn ) );
        memcpy ( &plogi.node_wwn, &els->port->node_wwn,
                 sizeof ( plogi.node_wwn ) );
        plogi.class3.flags = htons ( FC_LOGIN_CLASS_VALID |
                                     FC_LOGIN_CLASS_SEQUENTIAL );
        plogi.class3.mtu = htons ( FC_LOGIN_DEFAULT_MTU );
        plogi.class3.max_seq = htons ( FC_LOGIN_DEFAULT_MAX_SEQ );
        plogi.class3.max_seq_per_xchg = 1;
 
        /* Transmit PLOGI */
        return fc_els_tx ( els, &plogi, sizeof ( plogi ) );
}
 
/**
 * Receive PLOGI
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_plogi_rx ( struct fc_els *els, void *data, size_t len ) {
        struct fc_login_frame *plogi;
        struct fc_peer *peer;
        int rc;
 
        /* Sanity checks */
        if ( len < sizeof ( *plogi ) ) {
                DBGC ( els, FCELS_FMT " received underlength frame:\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, data, len );
                rc = -EINVAL;
                goto err_sanity;
        }
        plogi = data;
        if ( ! fc_link_ok ( &els->port->link ) ) {
                DBGC ( els, FCELS_FMT " received while port link is down\n",
                       FCELS_ARGS ( els ) );
                rc = -EINVAL;
                goto err_sanity;
        }
 
        /* Extract parameters */
        DBGC ( els, FCELS_FMT " has node %s\n", FCELS_ARGS ( els ),
               fc_ntoa ( &plogi->node_wwn ) );
        DBGC ( els, FCELS_FMT " has port %s as %s\n",
               FCELS_ARGS ( els ), fc_ntoa ( &plogi->port_wwn ),
               fc_id_ntoa ( &els->peer_port_id ) );
 
        /* Get peer */
        peer = fc_peer_get_wwn ( &plogi->port_wwn );
        if ( ! peer ) {
                DBGC ( els, FCELS_FMT " could not create peer\n",
                       FCELS_ARGS ( els ) );
                rc = -ENOMEM;
                goto err_peer_get_wwn;
        }
 
        /* Record login */
        if ( ( rc = fc_peer_login ( peer, els->port,
                                    &els->peer_port_id ) ) != 0 ) {
                DBGC ( els, FCELS_FMT " could not log in peer: %s\n",
                       FCELS_ARGS ( els ), strerror ( rc ) );
                goto err_login;
        }
 
        /* Transmit response, if applicable */
        if ( ! fc_els_is_request ( els ) ) {
                if ( ( rc = fc_els_plogi_tx ( els ) ) != 0 )
                        goto err_plogi_tx;
        }
 
        /* Drop temporary reference to peer */
        fc_peer_put ( peer );
 
        return 0;
 
 err_plogi_tx:
 err_login:
        fc_peer_put ( peer );
 err_peer_get_wwn:
 err_sanity:
        return rc;
}
 
/**
 * Detect PLOGI
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_plogi_detect ( struct fc_els *els __unused, const void *data,
                                 size_t len __unused ) {
        const struct fc_login_frame *plogi = data;
 
        /* Check for PLOGI */
        if ( plogi->command != FC_ELS_PLOGI )
                return -EINVAL;
 
        return 0;
}
 
/** PLOGI ELS handler */
struct fc_els_handler fc_els_plogi_handler __fc_els_handler = {
        .name           = "PLOGI",
        .tx             = fc_els_plogi_tx,
        .rx             = fc_els_plogi_rx,
        .detect         = fc_els_plogi_detect,
};
 
/**
 * Create PLOGI request
 *
 * @v parent            Parent interface
 * @v port              Fibre Channel port
 * @v peer_port_id      Peer port ID
 * @ret rc              Return status code
 */
int fc_els_plogi ( struct interface *parent, struct fc_port *port,
                   struct fc_port_id *peer_port_id ) {
 
        return fc_els_request ( parent, port, peer_port_id,
                                &fc_els_plogi_handler );
}
 
/******************************************************************************
 *
 * LOGO
 *
 ******************************************************************************
 */
 
/**
 * Transmit LOGO request
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_logo_tx ( struct fc_els *els ) {
        struct fc_logout_request_frame logo;
 
        /* Construct LOGO */
        memset ( &logo, 0, sizeof ( logo ) );
        logo.command = FC_ELS_LOGO;
        memcpy ( &logo.port_id, &els->port->port_id, sizeof ( logo.port_id ) );
        memcpy ( &logo.port_wwn, &els->port->port_wwn,
                 sizeof ( logo.port_wwn ) );
 
        /* Transmit LOGO */
        return fc_els_tx ( els, &logo, sizeof ( logo ) );
}
 
/**
 * Transmit LOGO response
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_logo_tx_response ( struct fc_els *els ) {
        struct fc_logout_response_frame logo;
 
        /* Construct LOGO */
        memset ( &logo, 0, sizeof ( logo ) );
        logo.command = FC_ELS_LS_ACC;
 
        /* Transmit LOGO */
        return fc_els_tx ( els, &logo, sizeof ( logo ) );
}
 
/**
 * Log out individual peer or whole port as applicable
 *
 * @v els               Fibre Channel ELS transaction
 * @v port_id           Peer port ID
 */
static void fc_els_logo_logout ( struct fc_els *els,
                                 struct fc_port_id *peer_port_id ) {
        struct fc_peer *peer;
 
        if ( ( memcmp ( peer_port_id, &fc_f_port_id,
                        sizeof ( *peer_port_id ) ) == 0 ) ||
             ( memcmp ( peer_port_id, &els->port->port_id,
                        sizeof ( *peer_port_id ) ) == 0 ) ) {
                fc_port_logout ( els->port, 0 );
        } else {
                peer = fc_peer_get_port_id ( els->port, peer_port_id );
                if ( peer ) {
                        fc_peer_logout ( peer, 0 );
                        fc_peer_put ( peer );
                }
        }
}
 
/**
 * Receive LOGO request
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_logo_rx_request ( struct fc_els *els, void *data,
                                    size_t len ) {
        struct fc_logout_request_frame *logo;
        int rc;
 
        /* Sanity check */
        if ( len < sizeof ( *logo ) ) {
                DBGC ( els, FCELS_FMT " received underlength frame:\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, data, len );
                return -EINVAL;
        }
        logo = data;
 
        DBGC ( els, FCELS_FMT " has port %s as %s\n", FCELS_ARGS ( els ),
               fc_ntoa ( &logo->port_wwn ), fc_id_ntoa ( &logo->port_id ) );
 
        /* Log out individual peer or whole port as applicable */
        fc_els_logo_logout ( els, &logo->port_id );
 
        /* Transmit repsonse */
        if ( ( rc = fc_els_logo_tx_response ( els ) ) != 0 )
                return rc;
 
        return 0;
}
 
/**
 * Receive LOGO response
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_logo_rx_response ( struct fc_els *els, void *data __unused,
                                     size_t len __unused ) {
 
        /* Log out individual peer or whole port as applicable */
        fc_els_logo_logout ( els, &els->peer_port_id );
 
        return 0;
}
 
/**
 * Receive LOGO
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_logo_rx ( struct fc_els *els, void *data, size_t len ) {
 
        if ( fc_els_is_request ( els ) ) {
                return fc_els_logo_rx_response ( els, data, len );
        } else {
                return fc_els_logo_rx_request ( els, data, len );
        }
}
 
/**
 * Detect LOGO
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_logo_detect ( struct fc_els *els __unused, const void *data,
                                size_t len __unused ) {
        const struct fc_logout_request_frame *logo = data;
 
        /* Check for LOGO */
        if ( logo->command != FC_ELS_LOGO )
                return -EINVAL;
 
        return 0;
}
 
/** LOGO ELS handler */
struct fc_els_handler fc_els_logo_handler __fc_els_handler = {
        .name           = "LOGO",
        .tx             = fc_els_logo_tx,
        .rx             = fc_els_logo_rx,
        .detect         = fc_els_logo_detect,
};
 
/**
 * Create LOGO request
 *
 * @v parent            Parent interface
 * @v port              Fibre Channel port
 * @v peer_port_id      Peer port ID
 * @ret rc              Return status code
 */
int fc_els_logo ( struct interface *parent, struct fc_port *port,
                  struct fc_port_id *peer_port_id ) {
 
        return fc_els_request ( parent, port, peer_port_id,
                                &fc_els_logo_handler );
}
 
/******************************************************************************
 *
 * PRLI
 *
 ******************************************************************************
 */
 
/**
 * Find PRLI descriptor
 *
 * @v type              Upper-layer protocol type
 * @ret descriptor      PRLI descriptor, or NULL
 */
static struct fc_els_prli_descriptor *
fc_els_prli_descriptor ( unsigned int type ) {
        struct fc_els_prli_descriptor *descriptor;
 
        for_each_table_entry ( descriptor, FC_ELS_PRLI_DESCRIPTORS ) {
                if ( descriptor->type == type )
                        return descriptor;
        }
        return NULL;
}
 
/**
 * Transmit PRLI
 *
 * @v els               Fibre Channel ELS transaction
 * @v descriptor        ELS PRLI descriptor
 * @v param             Service parameters
 * @ret rc              Return status code
 */
int fc_els_prli_tx ( struct fc_els *els,
                     struct fc_els_prli_descriptor *descriptor, void *param ) {
        struct {
                struct fc_prli_frame frame;
                uint8_t param[descriptor->param_len];
        } __attribute__ (( packed )) prli;
        struct fc_ulp *ulp;
        int rc;
 
        /* Get ULP */
        ulp = fc_ulp_get_port_id_type ( els->port, &els->peer_port_id,
                                        descriptor->type );
        if ( ! ulp ) {
                rc = -ENOMEM;
                goto err_get_port_id_type;
        }
 
        /* Build frame for transmission */
        memset ( &prli, 0, sizeof ( prli ) );
        prli.frame.command = fc_els_tx_command ( els, FC_ELS_PRLI );
        prli.frame.page_len =
                ( sizeof ( prli.frame.page ) + sizeof ( prli.param ) );
        prli.frame.len = htons ( sizeof ( prli ) );
        prli.frame.page.type = descriptor->type;
        if ( fc_els_is_request ( els ) ) {
                prli.frame.page.flags |= htons ( FC_PRLI_ESTABLISH );
        } else if ( fc_link_ok ( &ulp->link ) ) {
                prli.frame.page.flags |= htons ( FC_PRLI_ESTABLISH |
                                                    FC_PRLI_RESPONSE_SUCCESS );
        }
        memcpy ( &prli.param, param, sizeof ( prli.param ) );
 
        /* Transmit frame */
        if ( ( rc = fc_els_tx ( els, &prli, sizeof ( prli ) ) ) != 0 )
                goto err_tx;
 
        /* Drop temporary reference to ULP */
        fc_ulp_put ( ulp );
 
        return 0;
 
 err_tx:
        fc_ulp_put ( ulp );
 err_get_port_id_type:
        return rc;
}
 
/**
 * Receive PRLI
 *
 * @v els               Fibre Channel ELS transaction
 * @v descriptor        ELS PRLI descriptor
 * @v frame             ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
int fc_els_prli_rx ( struct fc_els *els,
                     struct fc_els_prli_descriptor *descriptor,
                     void *data, size_t len ) {
        struct {
                struct fc_prli_frame frame;
                uint8_t param[descriptor->param_len];
        } __attribute__ (( packed )) *prli;
        struct fc_ulp *ulp;
        int rc;
 
        /* Sanity check */
        if ( len < sizeof ( *prli ) ) {
                DBGC ( els, FCELS_FMT " received underlength frame:\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, data, len );
                rc = -EINVAL;
                goto err_sanity;
        }
        prli = data;
 
        DBGC ( els, FCELS_FMT " has parameters:\n", FCELS_ARGS ( els ) );
        DBGC_HDA ( els, 0, prli->param, sizeof ( prli->param ) );
 
        /* Get ULP */
        ulp = fc_ulp_get_port_id_type ( els->port, &els->peer_port_id,
                                        descriptor->type );
        if ( ! ulp ) {
                rc = -ENOMEM;
                goto err_get_port_id_type;
        }
 
        /* Sanity check */
        if ( ! fc_link_ok ( &ulp->peer->link ) ) {
                DBGC ( els, FCELS_FMT " received while peer link is down\n",
                       FCELS_ARGS ( els ) );
                rc = -EINVAL;
                goto err_link;
        }
 
        /* Log in ULP, if applicable */
        if ( prli->frame.page.flags & htons ( FC_PRLI_ESTABLISH ) ) {
                if ( ( rc = fc_ulp_login ( ulp, prli->param,
                                           sizeof ( prli->param ),
                                           fc_els_is_request ( els ) ) ) != 0 ){
                        DBGC ( els, FCELS_FMT " could not log in ULP: %s\n",
                               FCELS_ARGS ( els ), strerror ( rc ) );
                        goto err_login;
                }
        } else {
                if ( fc_els_is_request ( els ) ) {
                        fc_ulp_logout ( ulp, -EACCES );
                } else {
                        /* This is just an information-gathering PRLI; do not
                         * log in or out
                         */
                }
        }
 
        /* Transmit response, if applicable */
        if ( ! fc_els_is_request ( els ) ) {
                if ( ( rc = els->handler->tx ( els ) ) != 0 )
                        goto err_tx;
        }
 
        /* Drop temporary reference to ULP */
        fc_ulp_put ( ulp );
 
        return 0;
 
 err_tx:
 err_login:
 err_link:
        fc_ulp_put ( ulp );
 err_get_port_id_type:
 err_sanity:
        return rc;
}
 
/**
 * Detect PRLI
 *
 * @v els               Fibre Channel ELS transaction
 * @v descriptor        ELS PRLI descriptor
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
int fc_els_prli_detect ( struct fc_els *els __unused,
                         struct fc_els_prli_descriptor *descriptor,
                         const void *data, size_t len ) {
        const struct {
                struct fc_prli_frame frame;
                uint8_t param[descriptor->param_len];
        } __attribute__ (( packed )) *prli;
 
        /* Check for sufficient length to contain service parameter page */
        if ( len < sizeof ( *prli ) )
                return -EINVAL;
        prli = data;
 
        /* Check for PRLI */
        if ( prli->frame.command != FC_ELS_PRLI )
                return -EINVAL;
 
        /* Check for upper-layer protocol type */
        if ( prli->frame.page.type != descriptor->type )
                return -EINVAL;
 
        return 0;
}
 
/**
 * Create PRLI request
 *
 * @v parent            Parent interface
 * @v port              Fibre Channel port
 * @v peer_port_id      Peer port ID
 * @v type              Upper-layer protocol type
 * @ret rc              Return status code
 */
int fc_els_prli ( struct interface *parent, struct fc_port *port,
                  struct fc_port_id *peer_port_id, unsigned int type ) {
        struct fc_els_prli_descriptor *descriptor;
 
        /* Find a PRLI descriptor */
        descriptor = fc_els_prli_descriptor ( type );
        if ( ! descriptor )
                return -ENOTSUP;
 
        return fc_els_request ( parent, port, peer_port_id,
                                descriptor->handler );
}
 
/******************************************************************************
 *
 * RTV
 *
 ******************************************************************************
 */
 
/**
 * Transmit RTV response
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_rtv_tx_response ( struct fc_els *els ) {
        struct fc_rtv_response_frame rtv;
 
        /* Construct RTV */
        memset ( &rtv, 0, sizeof ( rtv ) );
        rtv.command = FC_ELS_LS_ACC;
        rtv.e_d_tov = htonl ( FC_LOGIN_DEFAULT_E_D_TOV );
 
        /* Transmit RTV */
        return fc_els_tx ( els, &rtv, sizeof ( rtv ) );
}
 
/**
 * Receive RTV
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_rtv_rx ( struct fc_els *els, void *data __unused,
                           size_t len __unused ) {
        int rc;
 
        DBGC ( els, FCELS_FMT "\n", FCELS_ARGS ( els ) );
 
        /* Transmit response */
        if ( ! fc_els_is_request ( els ) ) {
                if ( ( rc = fc_els_rtv_tx_response ( els ) ) != 0 )
                        return rc;
        }
 
        return 0;
}
 
/**
 * Detect RTV
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_rtv_detect ( struct fc_els *els __unused, const void *data,
                               size_t len __unused ) {
        const struct fc_rtv_request_frame *rtv = data;
 
        /* Check for RTV */
        if ( rtv->command != FC_ELS_RTV )
                return -EINVAL;
 
        return 0;
}
 
/** RTV ELS handler */
struct fc_els_handler fc_els_rtv_handler __fc_els_handler = {
        .name           = "RTV",
        .tx             = fc_els_unknown_tx,
        .rx             = fc_els_rtv_rx,
        .detect         = fc_els_rtv_detect,
};
 
/******************************************************************************
 *
 * ECHO
 *
 ******************************************************************************
 */
 
/** ECHO request data */
struct fc_echo_request_frame {
        /** ECHO frame header */
        struct fc_echo_frame_header echo;
        /** Magic marker */
        uint32_t magic;
} __attribute__ (( packed ));
 
/** ECHO magic marker */
#define FC_ECHO_MAGIC 0x69505845
 
/**
 * Transmit ECHO
 *
 * @v els               Fibre Channel ELS transaction
 * @ret rc              Return status code
 */
static int fc_els_echo_tx ( struct fc_els *els ) {
        struct fc_echo_request_frame echo;
 
        /* Construct ECHO */
        memset ( &echo, 0, sizeof ( echo ) );
        echo.echo.command = FC_ELS_ECHO;
        echo.magic = htonl ( FC_ECHO_MAGIC );
 
        /* Transmit ECHO */
        return fc_els_tx ( els, &echo, sizeof ( echo ) );
}
 
/**
 * Receive ECHO request
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_echo_rx_request ( struct fc_els *els, void *data,
                                    size_t len ) {
        struct {
                struct fc_echo_frame_header echo;
                char payload[ len - sizeof ( struct fc_echo_frame_header ) ];
        } *echo = data;
        int rc;
 
        DBGC ( els, FCELS_FMT "\n", FCELS_ARGS ( els ) );
 
        /* Transmit response */
        echo->echo.command = FC_ELS_LS_ACC;
        if ( ( rc = fc_els_tx ( els, echo, sizeof ( *echo ) ) ) != 0 )
                return rc;
 
        /* Nothing to do */
        return 0;
}
 
/**
 * Receive ECHO response
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_echo_rx_response ( struct fc_els *els, void *data,
                                     size_t len ) {
        struct fc_echo_request_frame *echo;
 
        DBGC ( els, FCELS_FMT "\n", FCELS_ARGS ( els ) );
 
        /* Sanity check */
        if ( len != sizeof ( *echo ) ) {
                DBGC ( els, FCELS_FMT " received underlength echo response\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, data, len );
                return -EIO;
        }
        echo = data;
 
        /* Check response is correct */
        if ( echo->magic != htonl ( FC_ECHO_MAGIC ) ) {
                DBGC ( els, FCELS_FMT " received bad echo response\n",
                       FCELS_ARGS ( els ) );
                DBGC_HDA ( els, 0, data, len );
                return -EIO;
        }
 
        return 0;
}
 
/**
 * Receive ECHO
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_echo_rx ( struct fc_els *els, void *data, size_t len ) {
 
        if ( fc_els_is_request ( els ) ) {
                return fc_els_echo_rx_response ( els, data, len );
        } else {
                return fc_els_echo_rx_request ( els, data, len );
        }
}
 
/**
 * Detect ECHO
 *
 * @v els               Fibre Channel ELS transaction
 * @v data              ELS frame
 * @v len               Length of ELS frame
 * @ret rc              Return status code
 */
static int fc_els_echo_detect ( struct fc_els *els __unused, const void *data,
                                size_t len __unused ) {
        const struct fc_echo_frame_header *echo = data;
 
        /* Check for ECHO */
        if ( echo->command != FC_ELS_ECHO )
                return -EINVAL;
 
        return 0;
}
 
/** ECHO ELS handler */
struct fc_els_handler fc_els_echo_handler __fc_els_handler = {
        .name           = "ECHO",
        .tx             = fc_els_echo_tx,
        .rx             = fc_els_echo_rx,
        .detect         = fc_els_echo_detect,
};