/*
 * 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 (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * Code shared by software-diagnosis and software-response modules.
 * The fmd module linkage info for the two modules lives in swde_main.c
 * (for software-diagnosis) and swrp_main.c (for software-response).
 */

#include "../common/sw_impl.h"

/*
 * Each subsidiary that is hosted is assigned a unique subsidiary id.  These
 * macros convert between the id of a subsidiary and the index used in keeping
 * track of subsidiaries.  Outside of this file these ids should remain
 * opaque.
 */
#define ID2IDX(id)      ((int)((id) & 0xff0000) >> 16)
#define IDX2ID(i)       ((id_t)((i) << 16) | 0x1d000000)

#define SUBIDVALID(msinfo, id)  (((int)(id) & 0xff00ffff) == 0x1d000000 && \
    ID2IDX(id) < (msinfo)->swms_dispcnt)

static struct {
        fmd_stat_t sw_recv_total;
        fmd_stat_t sw_recv_match;
        fmd_stat_t sw_recv_callback;
} sw_stats = {
        { "sw_recv_total", FMD_TYPE_UINT64,
            "total events received" },
        { "sw_recv_match", FMD_TYPE_UINT64,
            "events matching some subsidiary" },
        { "sw_recv_callback", FMD_TYPE_UINT64,
            "callbacks to all subsidiaries" },
};

#define BUMPSTAT(stat)          sw_stats.stat.fmds_value.ui64++
#define BUMPSTATN(stat, n)      sw_stats.stat.fmds_value.ui64 += (n)

/*
 * ========================== Event Receipt =================================
 *
 * The fmdo_recv entry point.  See which sub de/response agents have a
 * matching subscription and callback for the first match from each.
 * The sub de/response agents should dispatch *all* their subscriptions
 * via their registered dispatch table, including things like list.repaired.
 */
void
sw_recv(fmd_hdl_t *hdl, fmd_event_t *ep, nvlist_t *nvl, const char *class)
{
        struct sw_modspecific *msinfo;
        int calls = 0;
        int mod;

        BUMPSTAT(sw_recv_total);

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);

        /*
         * For each sub module that has a matching class pattern call the
         * registered callback for that sub DE.  Only one match per sub module
         * is allowed (the first match in its table, others are not checked).
         */
        for (mod = 0; mod < msinfo->swms_dispcnt; mod++) {
                const struct sw_disp *dp;
                sw_dispfunc_t *dispf = NULL;

                for (dp = (*msinfo->swms_disptbl)[mod];
                    dp != NULL && dp->swd_classpat != NULL; dp++) {
                        if (fmd_nvl_class_match(hdl, nvl, dp->swd_classpat)) {
                                dispf = dp->swd_func;
                                break;
                        }
                }
                if (dispf != NULL) {
                        calls++;
                        (*dispf)(hdl, ep, nvl, class, dp->swd_arg);
                }
        }

        BUMPSTAT(sw_recv_match);
        if (calls)
                BUMPSTATN(sw_recv_callback, calls);
}

/*
 * ========================== Timers ========================================
 *
 * A subsidiary can install a timer; it must pass an additional argument
 * identifying itself so that we can hand off to the appropriate
 * swsub_timeout function in the fmdo_timeout entry point when the timer fires.
 */
id_t
sw_timer_install(fmd_hdl_t *hdl, id_t who, void *arg, fmd_event_t *ep,
    hrtime_t hrt)
{
        struct sw_modspecific *msinfo;
        const struct sw_subinfo **subinfo;
        const struct sw_subinfo *sip;
        int slot, chosen = -1;
        id_t timerid;

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);
        if (!SUBIDVALID(msinfo, who))
                fmd_hdl_abort(hdl, "sw_timer_install: invalid subid %d\n", who);

        subinfo = *msinfo->swms_subinfo;
        sip = subinfo[ID2IDX(who)];

        if (sip-> swsub_timeout == NULL)
                fmd_hdl_abort(hdl, "sw_timer_install: no swsub_timeout\n");

        /*
         * Look for a slot.  Module entry points are single-threaded
         * in nature, but if someone installs a timer from a door
         * service function we're contended.
         */
        (void) pthread_mutex_lock(&msinfo->swms_timerlock);
        for (slot = 0; slot < SW_TIMER_MAX; slot++) {
                if (msinfo->swms_timers[slot].swt_state != SW_TMR_INUSE) {
                        chosen = slot;
                        break;
                }
        }

        if (chosen == -1)
                fmd_hdl_abort(hdl, "timer slots exhausted\n");

        msinfo->swms_timers[chosen].swt_state = SW_TMR_INUSE;
        msinfo->swms_timers[chosen].swt_ownerid = who;
        msinfo->swms_timers[chosen].swt_timerid = timerid =
            fmd_timer_install(hdl, arg, ep, hrt);

        (void) pthread_mutex_unlock(&msinfo->swms_timerlock);

        return (timerid);
}

/*
 * Look for a timer installed by a given subsidiary matching timerid.
 */
static int
subtimer_find(struct sw_modspecific *msinfo, id_t who, id_t timerid)
{
        int slot;

        for (slot = 0; slot < SW_TIMER_MAX; slot++) {
                if (msinfo->swms_timers[slot].swt_state == SW_TMR_INUSE &&
                    (who == -1 ||
                    msinfo->swms_timers[slot].swt_ownerid == who) &&
                    msinfo->swms_timers[slot].swt_timerid == timerid)
                        return (slot);
        }

        return (-1);
}

void
sw_timer_remove(fmd_hdl_t *hdl, id_t who, id_t timerid)
{
        struct sw_modspecific *msinfo;
        const struct sw_subinfo **subinfo;
        const struct sw_subinfo *sip;
        int slot;

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);
        if (!SUBIDVALID(msinfo, who))
                fmd_hdl_abort(hdl, "sw_timer_remove: invalid subid\n");

        subinfo = *msinfo->swms_subinfo;
        sip = subinfo[ID2IDX(who)];

        (void) pthread_mutex_lock(&msinfo->swms_timerlock);
        if ((slot = subtimer_find(msinfo, who, timerid)) == -1)
                fmd_hdl_abort(hdl, "sw_timer_remove: timerid %d not found "
                    "for %s\n", timerid, sip->swsub_name);
        fmd_timer_remove(hdl, timerid);
        msinfo->swms_timers[slot].swt_state = SW_TMR_RMVD;
        (void) pthread_mutex_unlock(&msinfo->swms_timerlock);
}

/*
 * The fmdo_timeout entry point.
 */
void
sw_timeout(fmd_hdl_t *hdl, id_t timerid, void *arg)
{
        struct sw_modspecific *msinfo;
        const struct sw_subinfo **subinfo;
        const struct sw_subinfo *sip;
        id_t owner;
        int slot;

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);

        (void) pthread_mutex_lock(&msinfo->swms_timerlock);
        if ((slot = subtimer_find(msinfo, -1, timerid)) == -1)
                fmd_hdl_abort(hdl, "sw_timeout: timerid %d not found\n");
        (void) pthread_mutex_unlock(&msinfo->swms_timerlock);

        owner = msinfo->swms_timers[slot].swt_ownerid;
        if (!SUBIDVALID(msinfo, owner))
                fmd_hdl_abort(hdl, "sw_timeout: invalid subid\n");

        subinfo = *msinfo->swms_subinfo;
        sip = subinfo[ID2IDX(owner)];

        sip->swsub_timeout(hdl, timerid, arg);
}

/*
 * ========================== sw_subinfo access =============================
 */

enum sw_casetype
sw_id_to_casetype(fmd_hdl_t *hdl, id_t who)
{
        struct sw_modspecific *msinfo;
        const struct sw_subinfo **subinfo;
        const struct sw_subinfo *sip;

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);
        if (!SUBIDVALID(msinfo, who))
                fmd_hdl_abort(hdl, "sw_id_to_casetype: invalid subid %d\n",
                    who);

        subinfo = *msinfo->swms_subinfo;
        sip = subinfo[ID2IDX(who)];

        if ((sip->swsub_casetype & SW_CASE_NONE) != SW_CASE_NONE)
                fmd_hdl_abort(hdl, "sw_id_to_casetype: bad case type %d "
                    "for %s\n", sip->swsub_casetype, sip->swsub_name);

        return (sip->swsub_casetype);
}

/*
 * Given a case type lookup the struct sw_subinfo for the subsidiary
 * that opens cases of that type.
 */
static const struct sw_subinfo *
sw_subinfo_bycase(fmd_hdl_t *hdl, enum sw_casetype type)
{
        struct sw_modspecific *msinfo;
        const struct sw_subinfo **subinfo;
        const struct sw_subinfo *sip;
        int i;

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);

        subinfo = *msinfo->swms_subinfo;
        for (i = 0; i < SW_SUB_MAX; i++) {
                sip = subinfo[i];
                if (sip->swsub_casetype == type)
                        return (sip);
        }

        return (NULL);
}

/*
 * Find the case close function for the given case type; can be NULL.
 */
swsub_case_close_func_t *
sw_sub_case_close_func(fmd_hdl_t *hdl, enum sw_casetype type)
{
        const struct sw_subinfo *sip;

        if ((sip = sw_subinfo_bycase(hdl, type)) == NULL)
                fmd_hdl_abort(hdl, "sw_sub_case_close_func: case type "
                    "%d not found\n", type);

        return (sip->swsub_case_close);
}

/*
 * Find the case verify function for the given case type; can be NULL.
 */
sw_case_vrfy_func_t *
sw_sub_case_vrfy_func(fmd_hdl_t *hdl, enum sw_casetype type)
{
        const struct sw_subinfo *sip;

        if ((sip = sw_subinfo_bycase(hdl, type)) == NULL)
                fmd_hdl_abort(hdl, "sw_sub_case_vrfy_func: case type "
                    "%d not found\n", type);

        return (sip->swsub_case_verify);
}

/*
 * ========================== Initialization ================================
 *
 * The two modules - software-diagnosis and software-response - call
 * sw_fmd_init from their _fmd_init entry points.
 */

static void
sw_add_callbacks(fmd_hdl_t *hdl, const char *who,
    const struct sw_disp *dp, int nelem, struct sw_modspecific *msinfo)
{
        int i;

        (*msinfo->swms_disptbl)[msinfo->swms_dispcnt++] = dp;

        if (dp == NULL)
                return;         /* subsidiary failed init */

        /* check that the nelem'th entry is the NULL termination */
        if (dp[nelem - 1].swd_classpat != NULL ||
            dp[nelem - 1].swd_func != NULL || dp[nelem - 1].swd_arg != NULL)
                fmd_hdl_abort(hdl, "subsidiary %s dispatch table not NULL-"
                    "terminated\n", who);

        /* now validate the entries; we allow NULL handlers */
        for (i = 0; i < nelem - 1; i++) {
                if (dp[i].swd_classpat == NULL)
                        fmd_hdl_abort(hdl, "subsidiary %s dispatch table entry "
                            "%d has a NULL pattern or function\n", who, i);
        }

}

int
sw_fmd_init(fmd_hdl_t *hdl, const fmd_hdl_info_t *hdlinfo,
    const struct sw_subinfo *(*subsid)[SW_SUB_MAX])
{
        struct sw_modspecific *msinfo;
        int i;

        if (fmd_hdl_register(hdl, FMD_API_VERSION, hdlinfo) != 0)
                return (0);

        if (fmd_prop_get_int32(hdl, "enable") != B_TRUE) {
                fmd_hdl_debug(hdl, "%s disabled though .conf file setting\n",
                    hdlinfo->fmdi_desc);
                fmd_hdl_unregister(hdl);
                return (0);
        }

        msinfo = fmd_hdl_zalloc(hdl, sizeof (*msinfo), FMD_SLEEP);

        msinfo->swms_subinfo = subsid;
        msinfo->swms_disptbl = fmd_hdl_zalloc(hdl,
            SW_SUB_MAX * sizeof (struct sw_disp *), FMD_SLEEP);

        (void) pthread_mutex_init(&msinfo->swms_timerlock, NULL);

        for (i = 0; i < SW_TIMER_MAX; i++)
                msinfo->swms_timers[i].swt_state = SW_TMR_UNTOUCHED;

        fmd_hdl_setspecific(hdl, (void *)msinfo);

        (void) fmd_stat_create(hdl, FMD_STAT_NOALLOC, sizeof (sw_stats) /
            sizeof (fmd_stat_t), (fmd_stat_t *)&sw_stats);

        /*
         * Initialize subsidiaries.  Each must make any subscription
         * requests it needs and return a pointer to a NULL-terminated
         * callback dispatch table and an indication of the number of
         * entries in that table including the NULL termination entry.
         */
        for (i = 0; i < SW_SUB_MAX; i++) {
                const struct sw_subinfo *sip = (*subsid)[i];
                const struct sw_disp *dp;
                char dbgbuf[80];
                int nelem = -1;
                int initrslt;

                if (!sip || sip->swsub_name == NULL)
                        break;

                initrslt = (*sip->swsub_init)(hdl, IDX2ID(i), &dp, &nelem);

                (void) snprintf(dbgbuf, sizeof (dbgbuf),
                    "subsidiary %d (id 0x%lx) '%s'",
                    i, IDX2ID(i), sip->swsub_name);

                switch (initrslt) {
                case SW_SUB_INIT_SUCCESS:
                        if (dp == NULL || nelem < 1)
                                fmd_hdl_abort(hdl, "%s returned dispatch "
                                    "table 0x%p and nelem %d\n",
                                    dbgbuf, dp, nelem);

                        fmd_hdl_debug(hdl, "%s initialized\n", dbgbuf);
                        sw_add_callbacks(hdl, sip->swsub_name, dp, nelem,
                            msinfo);
                        break;

                case SW_SUB_INIT_FAIL_VOLUNTARY:
                        fmd_hdl_debug(hdl, "%s chose not to initialize\n",
                            dbgbuf);
                        sw_add_callbacks(hdl, sip->swsub_name, NULL, -1,
                            msinfo);
                        break;

                case SW_SUB_INIT_FAIL_ERROR:
                        fmd_hdl_debug(hdl, "%s failed to initialize "
                            "because of an error\n", dbgbuf);
                        sw_add_callbacks(hdl, sip->swsub_name, NULL, -1,
                            msinfo);
                        break;

                default:
                        fmd_hdl_abort(hdl, "%s returned out-of-range result "
                            "%d\n", dbgbuf, initrslt);
                        break;
                }
        }

        return (1);
}

void
sw_fmd_fini(fmd_hdl_t *hdl)
{
        const struct sw_subinfo **subinfo;
        struct sw_modspecific *msinfo;
        int i;

        msinfo = (struct sw_modspecific *)fmd_hdl_getspecific(hdl);
        subinfo = *msinfo->swms_subinfo;

        (void) pthread_mutex_lock(&msinfo->swms_timerlock);
        for (i = 0; i < SW_TIMER_MAX; i++) {
                if (msinfo->swms_timers[i].swt_state != SW_TMR_INUSE)
                        continue;

                fmd_timer_remove(hdl, msinfo->swms_timers[i].swt_timerid);
                msinfo->swms_timers[i].swt_state = SW_TMR_RMVD;
        }
        (void) pthread_mutex_unlock(&msinfo->swms_timerlock);

        (void) pthread_mutex_destroy(&msinfo->swms_timerlock);

        for (i = 0; i < msinfo->swms_dispcnt; i++) {
                const struct sw_subinfo *sip = subinfo[i];

                if ((*msinfo->swms_disptbl)[i] == NULL)
                        continue;       /* swsub_init did not succeed */

                if (sip->swsub_fini != NULL)
                        (*sip->swsub_fini)(hdl);
        }

        fmd_hdl_free(hdl, msinfo->swms_disptbl,
            SW_SUB_MAX * sizeof (struct sw_disp *));

        fmd_hdl_setspecific(hdl, NULL);
        fmd_hdl_free(hdl, msinfo, sizeof (*msinfo));
}