io/idm/idm_conn_sm.c

	idm_conn_sm.c revision 30e7468f8f41aa30ada067b2c1d5d284046514da
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/cpuvar.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/modctl.h>
#include <sys/socket.h>
#include <sys/strsubr.h>
#include <sys/note.h>
#include <sys/sdt.h>

#define IDM_CONN_SM_STRINGS
#define IDM_CN_NOTIFY_STRINGS
#include <sys/idm/idm.h>

boolean_t   idm_sm_logging = B_FALSE;

extern idm_global_t idm; /* Global state */

static void
idm_conn_event_handler(void *event_ctx_opaque);

static void
idm_state_s1_free(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s2_xpt_wait(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s3_xpt_up(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s4_in_login(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s5_logged_in(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s6_in_logout(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_logout_req_timeout(void *arg);

static void
idm_state_s7_logout_req(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s8_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s9_init_error(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s10_in_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s11_complete(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_state_s12_enable_dm(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_update_state(idm_conn_t *ic, idm_conn_state_t new_state,
    idm_conn_event_ctx_t *event_ctx);

static void
idm_conn_unref(void *ic_void);

static idm_pdu_event_action_t
idm_conn_sm_validate_pdu(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx,
    idm_pdu_t *pdu);

static idm_status_t
idm_ffp_enable(idm_conn_t *ic);

static void
idm_ffp_disable(idm_conn_t *ic, idm_ffp_disable_t disable_type);

static void
idm_initial_login_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

static void
idm_login_success_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);

idm_status_t
idm_conn_sm_init(idm_conn_t *ic)
{
    char taskq_name[32];

    /*
     * Caller should have assigned a unique connection ID.  Use this
     * connection ID to create a unique connection name string
     */
    ASSERT(ic->ic_internal_cid != 0);
    (void) snprintf(taskq_name, sizeof (taskq_name) - 1, "conn_sm%08x",
        ic->ic_internal_cid);

    ic->ic_state_taskq = taskq_create(taskq_name, 1, minclsyspri, 4, 16384,
        TASKQ_PREPOPULATE);
    if (ic->ic_state_taskq == NULL) {
        return (IDM_STATUS_FAIL);
    }

    idm_sm_audit_init(&ic->ic_state_audit);
    mutex_init(&ic->ic_state_mutex, NULL, MUTEX_DEFAULT, NULL);
    cv_init(&ic->ic_state_cv, NULL, CV_DEFAULT, NULL);

    ic->ic_state = CS_S1_FREE;
    ic->ic_last_state = CS_S1_FREE;

    return (IDM_STATUS_SUCCESS);
}

void
idm_conn_sm_fini(idm_conn_t *ic)
{
    taskq_destroy(ic->ic_state_taskq);

    cv_destroy(&ic->ic_state_cv);
    /*
     * The thread that generated the event that got us here may still
     * hold the ic_state_mutex. Once it is released we can safely
     * destroy it since there is no way to locate the object now.
     */
    mutex_enter(&ic->ic_state_mutex);
    mutex_destroy(&ic->ic_state_mutex);
}

void
idm_conn_event(idm_conn_t *ic, idm_conn_event_t event, uintptr_t event_info)
{
    mutex_enter(&ic->ic_state_mutex);
    idm_conn_event_locked(ic, event, event_info, CT_NONE);
    mutex_exit(&ic->ic_state_mutex);
}


idm_status_t
idm_conn_reinstate_event(idm_conn_t *old_ic, idm_conn_t *new_ic)
{
    int result;

    mutex_enter(&old_ic->ic_state_mutex);
    if (((old_ic->ic_conn_type == CONN_TYPE_INI) &&
        (old_ic->ic_state != CS_S8_CLEANUP)) ||
        ((old_ic->ic_conn_type == CONN_TYPE_TGT) &&
        (old_ic->ic_state < CS_S5_LOGGED_IN))) {
        result = IDM_STATUS_FAIL;
    } else {
        result = IDM_STATUS_SUCCESS;
        new_ic->ic_reinstate_conn = old_ic;
        idm_conn_event_locked(new_ic->ic_reinstate_conn,
            CE_CONN_REINSTATE, (uintptr_t)new_ic, CT_NONE);
    }
    mutex_exit(&old_ic->ic_state_mutex);

    return (result);
}

void
idm_conn_tx_pdu_event(idm_conn_t *ic, idm_conn_event_t event,
    uintptr_t event_info)
{
    ASSERT(mutex_owned(&ic->ic_state_mutex));
    ic->ic_pdu_events++;
    idm_conn_event_locked(ic, event, event_info, CT_TX_PDU);
}

void
idm_conn_rx_pdu_event(idm_conn_t *ic, idm_conn_event_t event,
    uintptr_t event_info)
{
    ASSERT(mutex_owned(&ic->ic_state_mutex));
    ic->ic_pdu_events++;
    idm_conn_event_locked(ic, event, event_info, CT_RX_PDU);
}

void
idm_conn_event_locked(idm_conn_t *ic, idm_conn_event_t event,
    uintptr_t event_info, idm_pdu_event_type_t pdu_event_type)
{
    idm_conn_event_ctx_t    *event_ctx;

    idm_sm_audit_event(&ic->ic_state_audit, SAS_IDM_CONN,
        (int)ic->ic_state, (int)event, event_info);

    /*
     * It's very difficult to prevent a few straggling events
     * at the end.  For example idm_sorx_thread will generate
     * a CE_TRANSPORT_FAIL event when it exits.  Rather than
     * push complicated restrictions all over the code to
     * prevent this we will simply drop the events (and in
     * the case of PDU events release them appropriately)
     * since they are irrelevant once we are in a terminal state.
     * Of course those threads need to have appropriate holds on
     * the connection otherwise it might disappear.
     */
    if ((ic->ic_state == CS_S9_INIT_ERROR) ||
        (ic->ic_state == CS_S11_COMPLETE)) {
        if ((pdu_event_type == CT_TX_PDU) ||
            (pdu_event_type == CT_RX_PDU)) {
            ic->ic_pdu_events--;
            idm_pdu_complete((idm_pdu_t *)event_info,
                IDM_STATUS_SUCCESS);
        }
        IDM_SM_LOG(CE_NOTE, "*** Dropping event %s (%d) because of"
            "state %s (%d)",
            idm_ce_name[event], event,
            idm_cs_name[ic->ic_state], ic->ic_state);
        return;
    }

    /*
     * Normal event handling
     */
    idm_conn_hold(ic);

    event_ctx = kmem_zalloc(sizeof (*event_ctx), KM_SLEEP);
    event_ctx->iec_ic = ic;
    event_ctx->iec_event = event;
    event_ctx->iec_info = event_info;
    event_ctx->iec_pdu_event_type = pdu_event_type;

    (void) taskq_dispatch(ic->ic_state_taskq, &idm_conn_event_handler,
        event_ctx, TQ_SLEEP);
}

static void
idm_conn_event_handler(void *event_ctx_opaque)
{
    idm_conn_event_ctx_t *event_ctx = event_ctx_opaque;
    idm_conn_t *ic = event_ctx->iec_ic;
    idm_pdu_t *pdu = (idm_pdu_t *)event_ctx->iec_info;
    idm_pdu_event_action_t action;

    IDM_SM_LOG(CE_NOTE, "idm_conn_event_handler: conn %p event %s(%d)",
        (void *)ic, idm_ce_name[event_ctx->iec_event],
        event_ctx->iec_event);
    DTRACE_PROBE2(conn__event,
        idm_conn_t *, ic, idm_conn_event_ctx_t *, event_ctx);

    /*
     * Validate event
     */
    ASSERT(event_ctx->iec_event != CE_UNDEFINED);
    ASSERT3U(event_ctx->iec_event, <, CE_MAX_EVENT);

    /*
     * Validate current state
     */
    ASSERT(ic->ic_state != CS_S0_UNDEFINED);
    ASSERT3U(ic->ic_state, <, CS_MAX_STATE);

    /*
     * Validate PDU-related events against the current state.  If a PDU
     * is not allowed in the current state we change the event to a
     * protocol error.  This simplifies the state-specific event handlers.
     * For example the CS_S2_XPT_WAIT state only needs to handle the
     * CE_TX_PROTOCOL_ERROR and CE_RX_PROTOCOL_ERROR events since
     * no PDU's can be transmitted or received in that state.
     */
    event_ctx->iec_pdu_forwarded = B_FALSE;
    if (event_ctx->iec_pdu_event_type != CT_NONE) {
        ASSERT(pdu != NULL);
        action = idm_conn_sm_validate_pdu(ic, event_ctx, pdu);

        switch (action) {
        case CA_TX_PROTOCOL_ERROR:
            /*
             * Change event and forward the PDU
             */
            event_ctx->iec_event = CE_TX_PROTOCOL_ERROR;
            break;
        case CA_RX_PROTOCOL_ERROR:
            /*
             * Change event and forward the PDU.
             */
            event_ctx->iec_event = CE_RX_PROTOCOL_ERROR;
            break;
        case CA_FORWARD:
            /*
             * Let the state-specific event handlers take
             * care of it.
             */
            break;
        case CA_DROP:
            /*
             * It never even happened
             */
            IDM_SM_LOG(CE_NOTE, "*** drop PDU %p", (void *) pdu);
            idm_pdu_complete(pdu, IDM_STATUS_FAIL);
            break;
        default:
            ASSERT(0);
            break;
        }
    }

    switch (ic->ic_state) {
    case CS_S1_FREE:
        idm_state_s1_free(ic, event_ctx);
        break;
    case CS_S2_XPT_WAIT:
        idm_state_s2_xpt_wait(ic, event_ctx);
        break;
    case CS_S3_XPT_UP:
        idm_state_s3_xpt_up(ic, event_ctx);
        break;
    case CS_S4_IN_LOGIN:
        idm_state_s4_in_login(ic, event_ctx);
        break;
    case CS_S5_LOGGED_IN:
        idm_state_s5_logged_in(ic, event_ctx);
        break;
    case CS_S6_IN_LOGOUT:
        idm_state_s6_in_logout(ic, event_ctx);
        break;
    case CS_S7_LOGOUT_REQ:
        idm_state_s7_logout_req(ic, event_ctx);
        break;
    case CS_S8_CLEANUP:
        idm_state_s8_cleanup(ic, event_ctx);
        break;
    case CS_S9_INIT_ERROR:
        idm_state_s9_init_error(ic, event_ctx);
        break;
    case CS_S10_IN_CLEANUP:
        idm_state_s10_in_cleanup(ic, event_ctx);
        break;
    case CS_S11_COMPLETE:
        idm_state_s11_complete(ic, event_ctx);
        break;
    case CS_S12_ENABLE_DM:
        idm_state_s12_enable_dm(ic, event_ctx);
        break;
    default:
        ASSERT(0);
        break;
    }

    /*
     * Now that we've updated the state machine, if this was
     * a PDU-related event take the appropriate action on the PDU
     * (transmit it, forward it to the clients RX callback, drop
     * it, etc).
     */
    if (event_ctx->iec_pdu_event_type != CT_NONE) {
        switch (action) {
        case CA_TX_PROTOCOL_ERROR:
            idm_pdu_tx_protocol_error(ic, pdu);
            break;
        case CA_RX_PROTOCOL_ERROR:
            idm_pdu_rx_protocol_error(ic, pdu);
            break;
        case CA_FORWARD:
            if (!event_ctx->iec_pdu_forwarded) {
                if (event_ctx->iec_pdu_event_type ==
                    CT_RX_PDU) {
                    idm_pdu_rx_forward(ic, pdu);
                } else {
                    idm_pdu_tx_forward(ic, pdu);
                }
            }
            break;
        default:
            ASSERT(0);
            break;
        }
    }

    /*
     * Update outstanding PDU event count (see idm_pdu_tx for
     * how this is used)
     */
    if ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ||
        (event_ctx->iec_pdu_event_type == CT_RX_PDU)) {
        mutex_enter(&ic->ic_state_mutex);
        ic->ic_pdu_events--;
        mutex_exit(&ic->ic_state_mutex);
    }

    idm_conn_rele(ic);
    kmem_free(event_ctx, sizeof (*event_ctx));
}

static void
idm_state_s1_free(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    switch (event_ctx->iec_event) {
    case CE_CONNECT_REQ:
        /* T1 */
        idm_update_state(ic, CS_S2_XPT_WAIT, event_ctx);
        break;
    case CE_CONNECT_ACCEPT:
        /* T3 */
        idm_update_state(ic, CS_S3_XPT_UP, event_ctx);
        break;
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
        /* This should never happen */
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    default:
        ASSERT(0);
        /*NOTREACHED*/
    }
}


static void
idm_state_s2_xpt_wait(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    switch (event_ctx->iec_event) {
    case CE_CONNECT_SUCCESS:
        /* T4 */
        idm_update_state(ic, CS_S4_IN_LOGIN, event_ctx);
        break;
    case CE_CONNECT_FAIL:
    case CE_LOGOUT_OTHER_CONN_RCV:
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
        /* T2 */
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    default:
        ASSERT(0);
        /*NOTREACHED*/
    }
}


static void
idm_login_timeout(void *arg)
{
    idm_conn_t *ic = arg;

    idm_conn_event(ic, CE_LOGIN_TIMEOUT, NULL);
}

static void
idm_state_s3_xpt_up(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    switch (event_ctx->iec_event) {
    case CE_LOGIN_RCV:
        /* T4 */
        idm_initial_login_actions(ic, event_ctx);
        idm_update_state(ic, CS_S4_IN_LOGIN, event_ctx);
        break;
    case CE_LOGIN_TIMEOUT:
        /*
         * Don't need to cancel login timer since the timer is
         * presumed to be the source of this event.
         */
        (void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    case CE_CONNECT_REJECT:
    case CE_CONNECT_FAIL:
    case CE_TRANSPORT_FAIL:
    case CE_LOGOUT_OTHER_CONN_SND:
        /* T6 */
        (void) untimeout(ic->ic_state_timeout);
        (void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
        /* Don't care */
        break;
    default:
        ASSERT(0);
        /*NOTREACHED*/
    }
}

static void
idm_state_s4_in_login_fail_snd_done(idm_pdu_t *pdu, idm_status_t status)
{
    idm_conn_t      *ic = pdu->isp_ic;

    /*
     * This pdu callback can be invoked by the tx thread,
     * so run the disconnect code from another thread.
     */
    pdu->isp_status = status;
    idm_conn_event(ic, CE_LOGIN_FAIL_SND_DONE, (uintptr_t)pdu);
}

static void
idm_state_s4_in_login(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    idm_pdu_t *pdu;

    /*
     * Login timer should no longer be active after leaving this
     * state.
     */
    switch (event_ctx->iec_event) {
    case CE_LOGIN_SUCCESS_RCV:
    case CE_LOGIN_SUCCESS_SND:
        (void) untimeout(ic->ic_state_timeout);
        idm_login_success_actions(ic, event_ctx);
        if (ic->ic_rdma_extensions) {
            /* T19 */
            idm_update_state(ic, CS_S12_ENABLE_DM, event_ctx);
        } else {
            /* T5 */
            idm_update_state(ic, CS_S5_LOGGED_IN, event_ctx);
        }
        break;
    case CE_LOGIN_TIMEOUT:
        /* T7 */
        (void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    case CE_LOGIN_FAIL_SND_DONE:
        (void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    case CE_LOGIN_FAIL_SND:
        /*
         * Allow the logout response pdu to be sent and defer
         * the state machine update until the completion callback.
         * Only 1 level or callback interposition is allowed.
         */
        (void) untimeout(ic->ic_state_timeout);
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        ASSERT(ic->ic_client_callback == NULL);
        ic->ic_client_callback = pdu->isp_callback;
        pdu->isp_callback =
            idm_state_s4_in_login_fail_snd_done;
        break;
    case CE_LOGIN_FAIL_RCV:
        /*
         * Need to deliver this PDU to the initiator now because after
         * we update the state to CS_S9_INIT_ERROR the initiator will
         * no longer be in an appropriate state.
         */
        event_ctx->iec_pdu_forwarded = B_TRUE;
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        idm_pdu_rx_forward(ic, pdu);
        /* FALLTHROUGH */
    case CE_TRANSPORT_FAIL:
    case CE_LOGOUT_OTHER_CONN_SND:
    case CE_LOGOUT_OTHER_CONN_RCV:
        /* T7 */
        (void) untimeout(ic->ic_state_timeout);
        (void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    case CE_LOGIN_SND:
        /*
         * Initiator connections will see initial login PDU
         * in this state.  Target connections see initial
         * login PDU in "xpt up" state.
         */
        mutex_enter(&ic->ic_state_mutex);
        if (!(ic->ic_state_flags & CF_INITIAL_LOGIN)) {
            idm_initial_login_actions(ic, event_ctx);
        }
        mutex_exit(&ic->ic_state_mutex);
        break;
    case CE_MISC_TX:
    case CE_MISC_RX:
    case CE_LOGIN_RCV:
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
        /* Don't care */
        break;
    default:
        ASSERT(0);
        /*NOTREACHED*/
    }
}


static void
idm_state_s5_logged_in(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    switch (event_ctx->iec_event) {
    case CE_LOGOUT_THIS_CONN_RCV:
    case CE_LOGOUT_THIS_CONN_SND:
    case CE_LOGOUT_OTHER_CONN_RCV:
    case CE_LOGOUT_OTHER_CONN_SND:
        /* T9 */
        idm_ffp_disable(ic, FD_CONN_LOGOUT); /* Explicit logout */
        idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
        break;
    case CE_LOGOUT_SESSION_RCV:
    case CE_LOGOUT_SESSION_SND:
        /* T9 */
        idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */
        idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
        break;
    case CE_LOGOUT_SESSION_SUCCESS:
        /* T8 */
        idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */

        /* Close connection */
        if (IDM_CONN_ISTGT(ic)) {
            ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
        } else {
            ic->ic_transport_ops->it_ini_conn_disconnect(ic);
        }

        idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
        break;
    case CE_ASYNC_LOGOUT_RCV:
    case CE_ASYNC_LOGOUT_SND:
        /* T11 */
        idm_update_state(ic, CS_S7_LOGOUT_REQ, event_ctx);
        break;
    case CE_TRANSPORT_FAIL:
    case CE_ASYNC_DROP_CONN_RCV:
    case CE_ASYNC_DROP_CONN_SND:
    case CE_ASYNC_DROP_ALL_CONN_RCV:
    case CE_ASYNC_DROP_ALL_CONN_SND:
        /* T15 */
        idm_ffp_disable(ic, FD_CONN_FAIL); /* Implicit logout */
        idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
        break;
    case CE_MISC_TX:
    case CE_MISC_RX:
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
        /* Don't care */
        break;
    default:
        ASSERT(0);
    }
}

static void
idm_state_s6_in_logout_success_snd_done(idm_pdu_t *pdu, idm_status_t status)
{
    idm_conn_t      *ic = pdu->isp_ic;

    /*
     * This pdu callback can be invoked by the tx thread,
     * so run the disconnect code from another thread.
     */
    pdu->isp_status = status;
    idm_conn_event(ic, CE_LOGOUT_SUCCESS_SND_DONE, (uintptr_t)pdu);
}

static void
idm_state_s6_in_logout_fail_snd_done(idm_pdu_t *pdu, idm_status_t status)
{
    idm_conn_t      *ic = pdu->isp_ic;

    /*
     * This pdu callback can be invoked by the tx thread,
     * so run the disconnect code from another thread.
     */
    pdu->isp_status = status;
    idm_conn_event(ic, CE_LOGOUT_FAIL_SND_DONE, (uintptr_t)pdu);
}

static void
idm_state_s6_in_logout(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    idm_pdu_t *pdu;

    switch (event_ctx->iec_event) {
    case CE_LOGOUT_SUCCESS_SND_DONE:
        pdu = (idm_pdu_t *)event_ctx->iec_info;

        /* Close connection (if it's not already closed) */
        ASSERT(IDM_CONN_ISTGT(ic));
        ic->ic_transport_ops->it_tgt_conn_disconnect(ic);

        /* restore client callback */
        pdu->isp_callback =  ic->ic_client_callback;
        ic->ic_client_callback = NULL;
        idm_pdu_complete(pdu, pdu->isp_status);
        idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
        break;
    case CE_LOGOUT_FAIL_SND_DONE:
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        /* restore client callback */
        pdu->isp_callback =  ic->ic_client_callback;
        ic->ic_client_callback = NULL;
        idm_pdu_complete(pdu, pdu->isp_status);
        idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
        break;
    case CE_LOGOUT_SUCCESS_SND:
    case CE_LOGOUT_FAIL_SND:
        /*
         * Allow the logout response pdu to be sent and defer
         * the state machine update until the completion callback.
         * Only 1 level or callback interposition is allowed.
         */
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        ASSERT(ic->ic_client_callback == NULL);
        ic->ic_client_callback = pdu->isp_callback;
        if (event_ctx->iec_event == CE_LOGOUT_SUCCESS_SND) {
            pdu->isp_callback =
                idm_state_s6_in_logout_success_snd_done;
        } else {
            pdu->isp_callback =
                idm_state_s6_in_logout_fail_snd_done;
        }
        break;
    case CE_LOGOUT_SUCCESS_RCV:
        /*
         * Need to deliver this PDU to the initiator now because after
         * we update the state to CS_S11_COMPLETE the initiator will
         * no longer be in an appropriate state.
         */
        event_ctx->iec_pdu_forwarded = B_TRUE;
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        idm_pdu_rx_forward(ic, pdu);
        /* FALLTHROUGH */
    case CE_LOGOUT_SESSION_SUCCESS:
        /* T13 */

        /* Close connection (if it's not already closed) */
        if (IDM_CONN_ISTGT(ic)) {
            ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
        } else {
            ic->ic_transport_ops->it_ini_conn_disconnect(ic);
        }

        idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
        break;
    case CE_ASYNC_LOGOUT_RCV:
        /* T14 Do nothing */
        break;
    case CE_TRANSPORT_FAIL:
    case CE_ASYNC_DROP_CONN_RCV:
    case CE_ASYNC_DROP_CONN_SND:
    case CE_ASYNC_DROP_ALL_CONN_RCV:
    case CE_ASYNC_DROP_ALL_CONN_SND:
    case CE_LOGOUT_FAIL_RCV:
        idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
        break;
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
    case CE_MISC_TX:
    case CE_MISC_RX:
        /* Don't care */
        break;
    default:
        ASSERT(0);
    }
}


static void
idm_logout_req_timeout(void *arg)
{
    idm_conn_t *ic = arg;

    idm_conn_event(ic, CE_LOGOUT_TIMEOUT, NULL);
}

static void
idm_state_s7_logout_req(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    /* Must cancel logout timer before leaving this state */
    switch (event_ctx->iec_event) {
    case CE_LOGOUT_THIS_CONN_RCV:
    case CE_LOGOUT_THIS_CONN_SND:
    case CE_LOGOUT_OTHER_CONN_RCV:
    case CE_LOGOUT_OTHER_CONN_SND:
        /* T10 */
        if (IDM_CONN_ISTGT(ic)) {
            (void) untimeout(ic->ic_state_timeout);
        }
        idm_ffp_disable(ic, FD_CONN_LOGOUT); /* Explicit logout */
        idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
        break;
    case CE_LOGOUT_SESSION_RCV:
    case CE_LOGOUT_SESSION_SND:
        /* T10 */
        if (IDM_CONN_ISTGT(ic)) {
            (void) untimeout(ic->ic_state_timeout);
        }
        idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */
        idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
        break;
    case CE_ASYNC_LOGOUT_RCV:
    case CE_ASYNC_LOGOUT_SND:
        /* T12 Do nothing */
        break;
    case CE_TRANSPORT_FAIL:
    case CE_ASYNC_DROP_CONN_RCV:
    case CE_ASYNC_DROP_CONN_SND:
    case CE_ASYNC_DROP_ALL_CONN_RCV:
    case CE_ASYNC_DROP_ALL_CONN_SND:
        /* T16 */
        if (IDM_CONN_ISTGT(ic)) {
            (void) untimeout(ic->ic_state_timeout);
        }
        /* FALLTHROUGH */
    case CE_LOGOUT_TIMEOUT:
        idm_ffp_disable(ic, FD_CONN_FAIL); /* Implicit logout */
        idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
        break;
    case CE_LOGOUT_SESSION_SUCCESS:
        /* T18 */
        if (IDM_CONN_ISTGT(ic)) {
            (void) untimeout(ic->ic_state_timeout);
        }
        idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */

        /* Close connection (if it's not already closed) */
        if (IDM_CONN_ISTGT(ic)) {
            ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
        } else {
            ic->ic_transport_ops->it_ini_conn_disconnect(ic);
        }

        idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
        break;
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
    case CE_MISC_TX:
    case CE_MISC_RX:
        /* Don't care */
        break;
    default:
        ASSERT(0);
    }
}


static void
idm_cleanup_timeout(void *arg)
{
    idm_conn_t *ic = arg;

    idm_conn_event(ic, CE_CLEANUP_TIMEOUT, NULL);
}

static void
idm_state_s8_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    idm_pdu_t *pdu;

    /*
     * Need to cancel the cleanup timeout before leaving this state
     * if it hasn't already fired.
     */
    switch (event_ctx->iec_event) {
    case CE_LOGOUT_SUCCESS_RCV:
    case CE_LOGOUT_SUCCESS_SND:
    case CE_LOGOUT_SESSION_SUCCESS:
        (void) untimeout(ic->ic_state_timeout);
        /*FALLTHROUGH*/
    case CE_CLEANUP_TIMEOUT:
        /* M1 */
        idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
        break;
    case CE_LOGOUT_OTHER_CONN_RCV:
    case CE_LOGOUT_OTHER_CONN_SND:
        /* M2 */
        idm_update_state(ic, CS_S10_IN_CLEANUP, event_ctx);
        break;
    case CE_LOGOUT_SUCCESS_SND_DONE:
    case CE_LOGOUT_FAIL_SND_DONE:
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        /* restore client callback */
        pdu->isp_callback =  ic->ic_client_callback;
        ic->ic_client_callback = NULL;
        idm_pdu_complete(pdu, pdu->isp_status);
        break;
    case CE_LOGOUT_SESSION_RCV:
    case CE_LOGOUT_SESSION_SND:
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
    case CE_MISC_TX:
    case CE_MISC_RX:
    case CE_TRANSPORT_FAIL:
    case CE_LOGOUT_TIMEOUT:
        /* Don't care */
        break;
    default:
        ASSERT(0);
    }
}

/* ARGSUSED */
static void
idm_state_s9_init_error(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    if (ic->ic_conn_type == CONN_TYPE_INI) {
        mutex_enter(&ic->ic_state_mutex);
        ic->ic_state_flags |= CF_ERROR;
        ic->ic_conn_sm_status = IDM_STATUS_FAIL;
        cv_signal(&ic->ic_state_cv);
        mutex_exit(&ic->ic_state_mutex);
    }
}

static void
idm_state_s10_in_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    idm_pdu_t *pdu;

    /*
     * Need to cancel the cleanup timeout before leaving this state
     * if it hasn't already fired.
     */
    switch (event_ctx->iec_event) {
    case CE_LOGOUT_FAIL_RCV:
    case CE_LOGOUT_FAIL_SND:
        idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
        break;
    case CE_LOGOUT_SUCCESS_SND:
    case CE_LOGOUT_SUCCESS_RCV:
    case CE_LOGOUT_SESSION_SUCCESS:
        (void) untimeout(ic->ic_state_timeout);
        /*FALLTHROUGH*/
    case CE_CLEANUP_TIMEOUT:
        idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
        break;
    case CE_LOGOUT_SUCCESS_SND_DONE:
    case CE_LOGOUT_FAIL_SND_DONE:
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        /* restore client callback */
        pdu->isp_callback =  ic->ic_client_callback;
        ic->ic_client_callback = NULL;
        idm_pdu_complete(pdu, pdu->isp_status);
        break;
    case CE_TX_PROTOCOL_ERROR:
    case CE_RX_PROTOCOL_ERROR:
    case CE_MISC_TX:
    case CE_MISC_RX:
    case CE_LOGOUT_TIMEOUT:
        /* Don't care */
        break;
    default:
        ASSERT(0);
    }
}

/* ARGSUSED */
static void
idm_state_s11_complete(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    idm_pdu_t *pdu;

    /*
     * Cleanup logout success/fail completion if it's been delayed
     * until now.
     */
    switch (event_ctx->iec_event) {
    case CE_LOGOUT_SUCCESS_SND_DONE:
    case CE_LOGOUT_FAIL_SND_DONE:
        pdu = (idm_pdu_t *)event_ctx->iec_info;
        /* restore client callback */
        pdu->isp_callback =  ic->ic_client_callback;
        ic->ic_client_callback = NULL;
        idm_pdu_complete(pdu, pdu->isp_status);
        break;
    }
}

static void
idm_state_s12_enable_dm(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    switch (event_ctx->iec_event) {
    case CE_ENABLE_DM_SUCCESS:
        /* T20 */
        idm_update_state(ic, CS_S5_LOGGED_IN, event_ctx);
        break;
    case CE_ENABLE_DM_FAIL:
        /* T21 */
        idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
        break;
    case CE_TRANSPORT_FAIL:
        /*
         * We expect to always hear back from the transport layer
         * once we have an "enable data-mover" request outstanding.
         * Therefore we'll ignore other events that may occur even
         * when they clearly indicate a problem and wait for
         * CE_ENABLE_DM_FAIL.  On a related note this means the
         * transport must ensure that it eventually completes the
         * "enable data-mover" operation with either success or
         * failure -- otherwise we'll be stuck here.
         */
        break;
    default:
        ASSERT(0);
        break;
    }
}

static void
idm_update_state(idm_conn_t *ic, idm_conn_state_t new_state,
    idm_conn_event_ctx_t *event_ctx)
{
    int rc;
    idm_status_t idm_status;

    /*
     * Validate new state
     */
    ASSERT(new_state != CS_S0_UNDEFINED);
    ASSERT3U(new_state, <, CS_MAX_STATE);

    /*
     * Update state in context.  We protect this with a mutex
     * even though the state machine code is single threaded so that
     * other threads can check the state value atomically.
     */
    new_state = (new_state < CS_MAX_STATE) ?
        new_state : CS_S0_UNDEFINED;

    IDM_SM_LOG(CE_NOTE, "idm_update_state: conn %p, evt %s(%d), "
        "%s(%d) --> %s(%d)", (void *)ic,
        idm_ce_name[event_ctx->iec_event], event_ctx->iec_event,
        idm_cs_name[ic->ic_state], ic->ic_state,
        idm_cs_name[new_state], new_state);

    DTRACE_PROBE2(conn__state__change,
        idm_conn_t *, ic, idm_conn_state_t, new_state);

    mutex_enter(&ic->ic_state_mutex);
    idm_sm_audit_state_change(&ic->ic_state_audit, SAS_IDM_CONN,
        (int)ic->ic_state, (int)new_state);
    ic->ic_last_state = ic->ic_state;
    ic->ic_state = new_state;
    cv_signal(&ic->ic_state_cv);
    mutex_exit(&ic->ic_state_mutex);

    switch (ic->ic_state) {
    case CS_S1_FREE:
        ASSERT(0); /* Initial state, can't return */
        break;
    case CS_S2_XPT_WAIT:
        if ((rc = idm_ini_conn_finish(ic)) != 0) {
            idm_conn_event(ic, CE_CONNECT_FAIL, NULL);
        } else {
            idm_conn_event(ic, CE_CONNECT_SUCCESS, NULL);
        }
        break;
    case CS_S3_XPT_UP:
        /*
         * Finish any connection related setup including
         * waking up the idm_tgt_conn_accept thread.
         * and starting the login timer.  If the function
         * fails then we return to "free" state.
         */
        if ((rc = idm_tgt_conn_finish(ic)) != IDM_STATUS_SUCCESS) {
            switch (rc) {
            case IDM_STATUS_REJECT:
                idm_conn_event(ic, CE_CONNECT_REJECT, NULL);
                break;
            default:
                idm_conn_event(ic, CE_CONNECT_FAIL, NULL);
                break;
            }
        }

        /*
         * First login received will cause a transition to
         * CS_S4_IN_LOGIN.  Start login timer.
         */
        ic->ic_state_timeout = timeout(idm_login_timeout, ic,
            drv_usectohz(IDM_LOGIN_SECONDS*1000000));
        break;
    case CS_S4_IN_LOGIN:
        if (ic->ic_conn_type == CONN_TYPE_INI) {
            mutex_enter(&ic->ic_state_mutex);
            ic->ic_state_flags |= CF_LOGIN_READY;
            cv_signal(&ic->ic_state_cv);
            mutex_exit(&ic->ic_state_mutex);
        }
        break;
    case CS_S5_LOGGED_IN:
        ASSERT(!ic->ic_ffp);
        /*
         * IDM can go to FFP before the initiator but it
         * needs to go to FFP after the target (IDM target should
         * go to FFP after notify_ack).
         */
        idm_status = idm_ffp_enable(ic);
        if (idm_status != IDM_STATUS_SUCCESS) {
            idm_conn_event(ic, CE_TRANSPORT_FAIL, NULL);
        }

        if (ic->ic_reinstate_conn) {
            /* Connection reinstatement is complete */
            idm_conn_event_locked(ic->ic_reinstate_conn,
                CE_CONN_REINSTATE_SUCCESS, NULL, CT_NONE);
        }
        break;
    case CS_S6_IN_LOGOUT:
        break;
    case CS_S7_LOGOUT_REQ:
        /* Start logout timer for target connections */
        if (IDM_CONN_ISTGT(ic)) {
            ic->ic_state_timeout = timeout(idm_logout_req_timeout,
                ic, drv_usectohz(IDM_LOGOUT_SECONDS*1000000));
        }
        break;
    case CS_S8_CLEANUP:
        /* Close connection (if it's not already closed) */
        if (IDM_CONN_ISTGT(ic)) {
            ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
        } else {
            ic->ic_transport_ops->it_ini_conn_disconnect(ic);
        }

        /* Stop executing active tasks */
        idm_task_abort(ic, NULL, AT_INTERNAL_SUSPEND);

        /* Start logout timer */
        ic->ic_state_timeout = timeout(idm_cleanup_timeout, ic,
            drv_usectohz(IDM_CLEANUP_SECONDS*1000000));
        break;
    case CS_S10_IN_CLEANUP:
        break;
    case CS_S9_INIT_ERROR:
        if (IDM_CONN_ISTGT(ic)) {
            ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
        } else {
            mutex_enter(&ic->ic_state_mutex);
            ic->ic_state_flags |= CF_ERROR;
            ic->ic_conn_sm_status = IDM_STATUS_FAIL;
            cv_signal(&ic->ic_state_cv);
            mutex_exit(&ic->ic_state_mutex);
            if (ic->ic_last_state != CS_S1_FREE &&
                ic->ic_last_state != CS_S2_XPT_WAIT) {
                ic->ic_transport_ops->it_ini_conn_disconnect(
                    ic);
            } else {
                (void) idm_notify_client(ic, CN_CONNECT_FAIL,
                    NULL);
            }
        }
        /*FALLTHROUGH*/
    case CS_S11_COMPLETE:
        /*
         * No more traffic on this connection.  If this is an
         * initiator connection and we weren't connected yet
         * then don't send the "connect lost" event.
         * It's useful to the initiator to know whether we were
         * logging in at the time so send that information in the
         * data field.
         */
        if (IDM_CONN_ISTGT(ic) ||
            ((ic->ic_last_state != CS_S1_FREE) &&
            (ic->ic_last_state != CS_S2_XPT_WAIT))) {
            (void) idm_notify_client(ic, CN_CONNECT_LOST,
                (uintptr_t)(ic->ic_last_state == CS_S4_IN_LOGIN));
        }

        /* Abort all tasks */
        idm_task_abort(ic, NULL, AT_INTERNAL_ABORT);

        /*
         * Handle terminal state actions on the global taskq so
         * we can clean up all the connection resources from
         * a separate thread context.
         */
        idm_refcnt_async_wait_ref(&ic->ic_refcnt, &idm_conn_unref);
        break;
    case CS_S12_ENABLE_DM:

        /*
         * The Enable DM state indicates the initiator to initiate
         * the hello sequence and the target to get ready to accept
         * the iSER Hello Message.
         */
        idm_status = (IDM_CONN_ISINI(ic)) ?
            ic->ic_transport_ops->it_ini_enable_datamover(ic) :
            ic->ic_transport_ops->it_tgt_enable_datamover(ic);

        if (idm_status == IDM_STATUS_SUCCESS) {
            idm_conn_event(ic, CE_ENABLE_DM_SUCCESS, NULL);
        } else {
            idm_conn_event(ic, CE_ENABLE_DM_FAIL, NULL);
        }

        break;
    }
}


static void
idm_conn_unref(void *ic_void)
{
    idm_conn_t *ic = ic_void;

    /*
     * Client should not be notified that the connection is destroyed
     * until all references on the idm connection have been removed.
     * Otherwise references on the associated client context would need
     * to be tracked separately which seems like a waste (at least when
     * there is a one for one correspondence with references on the
     * IDM connection).
     */
    if (IDM_CONN_ISTGT(ic)) {
        (void) idm_notify_client(ic, CN_CONNECT_DESTROY, NULL);
        idm_svc_conn_destroy(ic);
    } else {
        /* Initiator may destroy connection during this call */
        (void) idm_notify_client(ic, CN_CONNECT_DESTROY, NULL);
    }
}


static idm_pdu_event_action_t
idm_conn_sm_validate_pdu(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx,
    idm_pdu_t *pdu)
{
    char            *reason_string;
    idm_pdu_event_action_t  action;

    ASSERT((event_ctx->iec_pdu_event_type == CT_RX_PDU) ||
        (event_ctx->iec_pdu_event_type == CT_TX_PDU));

    /*
     * Let's check the simple stuff first.  Make sure if this is a
     * target connection that the PDU is appropriate for a target
     * and if this is an initiator connection that the PDU is
     * appropriate for an initiator.  This code is not in the data
     * path so organization is more important than performance.
     */
    switch (IDM_PDU_OPCODE(pdu)) {
    case ISCSI_OP_NOOP_OUT:
    case ISCSI_OP_SCSI_CMD:
    case ISCSI_OP_SCSI_TASK_MGT_MSG:
    case ISCSI_OP_LOGIN_CMD:
    case ISCSI_OP_TEXT_CMD:
    case ISCSI_OP_SCSI_DATA:
    case ISCSI_OP_LOGOUT_CMD:
    case ISCSI_OP_SNACK_CMD:
        /*
         * Only the initiator should send these PDU's and
         * only the target should receive them.
         */
        if (IDM_CONN_ISINI(ic) &&
            (event_ctx->iec_pdu_event_type == CT_RX_PDU)) {
            reason_string = "Invalid RX PDU for initiator";
            action = CA_RX_PROTOCOL_ERROR;
            goto validate_pdu_done;
        }

        if (IDM_CONN_ISTGT(ic) &&
            (event_ctx->iec_pdu_event_type == CT_TX_PDU)) {
            reason_string = "Invalid TX PDU for target";
            action = CA_TX_PROTOCOL_ERROR;
            goto validate_pdu_done;
        }
        break;
    case ISCSI_OP_NOOP_IN:
    case ISCSI_OP_SCSI_RSP:
    case ISCSI_OP_SCSI_TASK_MGT_RSP:
    case ISCSI_OP_LOGIN_RSP:
    case ISCSI_OP_TEXT_RSP:
    case ISCSI_OP_SCSI_DATA_RSP:
    case ISCSI_OP_LOGOUT_RSP:
    case ISCSI_OP_RTT_RSP:
    case ISCSI_OP_ASYNC_EVENT:
    case ISCSI_OP_REJECT_MSG:
        /*
         * Only the target should send these PDU's and
         * only the initiator should receive them.
         */
        if (IDM_CONN_ISTGT(ic) &&
            (event_ctx->iec_pdu_event_type == CT_RX_PDU)) {
            reason_string = "Invalid RX PDU for target";
            action = CA_RX_PROTOCOL_ERROR;
            goto validate_pdu_done;
        }

        if (IDM_CONN_ISINI(ic) &&
            (event_ctx->iec_pdu_event_type == CT_TX_PDU)) {
            reason_string = "Invalid TX PDU for initiator";
            action = CA_TX_PROTOCOL_ERROR;
            goto validate_pdu_done;
        }
        break;
    default:
        reason_string = "Unknown PDU Type";
        action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
            CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
        goto validate_pdu_done;
    }

    /*
     * Now validate the opcodes against the current state.
     */
    reason_string = "PDU not allowed in current state";
    switch (IDM_PDU_OPCODE(pdu)) {
    case ISCSI_OP_NOOP_OUT:
    case ISCSI_OP_NOOP_IN:
        /*
         * Obviously S1-S3 are not allowed since login hasn't started.
         * S8 is probably out as well since the connection has been
         * dropped.
         */
        switch (ic->ic_state) {
        case CS_S4_IN_LOGIN:
        case CS_S5_LOGGED_IN:
        case CS_S6_IN_LOGOUT:
        case CS_S7_LOGOUT_REQ:
            action = CA_FORWARD;
            goto validate_pdu_done;
        case CS_S8_CLEANUP:
        case CS_S10_IN_CLEANUP:
            action = CA_DROP;
            break;
        default:
            action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
                CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
            goto validate_pdu_done;
        }
        /*NOTREACHED*/
    case ISCSI_OP_SCSI_CMD:
    case ISCSI_OP_SCSI_RSP:
    case ISCSI_OP_SCSI_TASK_MGT_MSG:
    case ISCSI_OP_SCSI_TASK_MGT_RSP:
    case ISCSI_OP_SCSI_DATA:
    case ISCSI_OP_SCSI_DATA_RSP:
    case ISCSI_OP_RTT_RSP:
    case ISCSI_OP_SNACK_CMD:
    case ISCSI_OP_TEXT_CMD:
    case ISCSI_OP_TEXT_RSP:
        switch (ic->ic_state) {
        case CS_S5_LOGGED_IN:
        case CS_S6_IN_LOGOUT:
        case CS_S7_LOGOUT_REQ:
            action = CA_FORWARD;
            goto validate_pdu_done;
        case CS_S8_CLEANUP:
        case CS_S10_IN_CLEANUP:
            action = CA_DROP;
            break;
        default:
            action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
                CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
            goto validate_pdu_done;
        }
        /*NOTREACHED*/
    case ISCSI_OP_LOGOUT_CMD:
    case ISCSI_OP_LOGOUT_RSP:
    case ISCSI_OP_REJECT_MSG:
    case ISCSI_OP_ASYNC_EVENT:
        switch (ic->ic_state) {
        case CS_S5_LOGGED_IN:
        case CS_S6_IN_LOGOUT:
        case CS_S7_LOGOUT_REQ:
            action = CA_FORWARD;
            goto validate_pdu_done;
        case CS_S8_CLEANUP:
        case CS_S10_IN_CLEANUP:
            action = CA_DROP;
            break;
        default:
            action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
                CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
            goto validate_pdu_done;
        }
        /*NOTREACHED*/
    case ISCSI_OP_LOGIN_CMD:
    case ISCSI_OP_LOGIN_RSP:
        switch (ic->ic_state) {
        case CS_S3_XPT_UP:
        case CS_S4_IN_LOGIN:
            action = CA_FORWARD;
            goto validate_pdu_done;
        default:
            action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
                CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
            goto validate_pdu_done;
        }
        /*NOTREACHED*/
    default:
        /* This should never happen -- we already checked above */
        ASSERT(0);
        /*NOTREACHED*/
    }

    action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
        CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);

validate_pdu_done:
    if (action != CA_FORWARD) {
        DTRACE_PROBE2(idm__int__protocol__error,
            idm_conn_event_ctx_t *, event_ctx,
            char *, reason_string);
    }

    return (action);
}

/* ARGSUSED */
void
idm_pdu_tx_protocol_error(idm_conn_t *ic, idm_pdu_t *pdu)
{
    /*
     * Return the PDU to the caller indicating it was a protocol error.
     * Caller can take appropriate action.
     */
    idm_pdu_complete(pdu, IDM_STATUS_PROTOCOL_ERROR);
}

void
idm_pdu_rx_protocol_error(idm_conn_t *ic, idm_pdu_t *pdu)
{
    /*
     * Forward PDU to caller indicating it is a protocol error.
     * Caller should take appropriate action.
     */
    (*ic->ic_conn_ops.icb_rx_error)(ic, pdu, IDM_STATUS_PROTOCOL_ERROR);
}

idm_status_t
idm_notify_client(idm_conn_t *ic, idm_client_notify_t cn, uintptr_t data)
{
    /*
     * We may want to make this more complicated at some point but
     * for now lets just call the client's notify function and return
     * the status.
     */
    cn = (cn > CN_MAX) ? CN_MAX : cn;
    IDM_SM_LOG(CE_NOTE, "idm_notify_client: ic=%p %s(%d)\n",
        (void *)ic, idm_cn_strings[cn], cn);
    return ((*ic->ic_conn_ops.icb_client_notify)(ic, cn, data));
}

static idm_status_t
idm_ffp_enable(idm_conn_t *ic)
{
    idm_status_t rc;

    /*
     * On the initiator side the client will see this notification
     * before the actual login succes PDU.  This shouldn't be a big
     * deal since the initiator drives the connection.  It can simply
     * wait for the login response then start sending SCSI commands.
     * Kind ugly though compared with the way things work on target
     * connections.
     */
    mutex_enter(&ic->ic_state_mutex);
    ic->ic_ffp = B_TRUE;
    mutex_exit(&ic->ic_state_mutex);

    rc = idm_notify_client(ic, CN_FFP_ENABLED, NULL);
    if (rc != IDM_STATUS_SUCCESS) {
        mutex_enter(&ic->ic_state_mutex);
        ic->ic_ffp = B_FALSE;
        mutex_exit(&ic->ic_state_mutex);
    }
    return (rc);
}

static void
idm_ffp_disable(idm_conn_t *ic, idm_ffp_disable_t disable_type)
{
    mutex_enter(&ic->ic_state_mutex);
    ic->ic_ffp = B_FALSE;
    mutex_exit(&ic->ic_state_mutex);

    /* Client can't "fail" CN_FFP_DISABLED */
    (void) idm_notify_client(ic, CN_FFP_DISABLED,
        (uintptr_t)disable_type);
}

static void
idm_initial_login_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    ASSERT((event_ctx->iec_event == CE_LOGIN_RCV) ||
        (event_ctx->iec_event == CE_LOGIN_SND));

    /*
     * Currently it's not clear what we would do here -- since
     * we went to the trouble of coding an "initial login" hook
     * we'll leave it in for now.  Remove before integration if
     * it's not used for anything.
     */
    ic->ic_state_flags |= CF_INITIAL_LOGIN;
}

static void
idm_login_success_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
{
    idm_pdu_t       *pdu = (idm_pdu_t *)event_ctx->iec_info;
    iscsi_login_hdr_t   *login_req =
        (iscsi_login_hdr_t *)pdu->isp_hdr;

    ASSERT((event_ctx->iec_event == CE_LOGIN_SUCCESS_RCV) ||
        (event_ctx->iec_event == CE_LOGIN_SUCCESS_SND));

    /*
     * Save off CID
     */
    mutex_enter(&ic->ic_state_mutex);
    ic->ic_login_cid = ntohs(login_req->cid);
    ic->ic_login_info_valid =  B_TRUE;

    mutex_exit(&ic->ic_state_mutex);
}