/*
 * 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.
 */

/*
 * This RCM module adds support to the RCM framework for an abstract
 * namespace for network devices (DLPI providers).
 */
#include <alloca.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <string.h>
#include <synch.h>
#include <libintl.h>
#include <errno.h>
#include <libdevinfo.h>
#include <sys/types.h>
#include <net/if.h>
#include <libdllink.h>
#include "rcm_module.h"

/*
 * Definitions
 */
#ifndef lint
#define _(x)    gettext(x)
#else
#define _(x)    x
#endif

#define CACHE_STALE     1       /* flags */
#define CACHE_NEW       2       /* flags */

/* operations */
#define NET_OFFLINE     1
#define NET_ONLINE      2
#define NET_REMOVE      3
#define NET_SUSPEND     4
#define NET_RESUME      5

typedef struct net_cache
{
        char                    *resource;
        datalink_id_t           linkid;
        int                     flags;
        struct net_cache        *next;
        struct net_cache        *prev;
} net_cache_t;

static net_cache_t      cache_head;
static net_cache_t      cache_tail;
static mutex_t          cache_lock;
static int              events_registered = 0;

static dladm_handle_t   dld_handle = NULL;

/* module interface routines */
static int net_register(rcm_handle_t *);
static int net_unregister(rcm_handle_t *);
static int net_getinfo(rcm_handle_t *, char *, id_t, uint_t, char **,
    char **, nvlist_t *, rcm_info_t **);
static int net_suspend(rcm_handle_t *, char *, id_t, timespec_t *,
    uint_t, char **, rcm_info_t **);
static int net_resume(rcm_handle_t *, char *, id_t, uint_t, char **,
    rcm_info_t **);
static int net_offline(rcm_handle_t *, char *, id_t, uint_t, char **,
    rcm_info_t **);
static int net_online(rcm_handle_t *, char *, id_t, uint_t, char **,
    rcm_info_t **);
static int net_remove(rcm_handle_t *, char *, id_t, uint_t, char **,
    rcm_info_t **);
static int net_notify_event(rcm_handle_t *, char *, id_t, uint_t,
    char **, nvlist_t *, rcm_info_t **);

/* module private routines */
static void free_cache(void);
static void update_cache(rcm_handle_t *hd);
static int devfs_entry(di_node_t node, di_minor_t minor, void *arg);
static void cache_remove(net_cache_t *node);
static net_cache_t *cache_lookup(const char *resource);
static void free_node(net_cache_t *);
static void cache_insert(net_cache_t *);

/*
 * Module-Private data
 */
static struct rcm_mod_ops net_ops = {
        RCM_MOD_OPS_VERSION,
        net_register,
        net_unregister,
        net_getinfo,
        net_suspend,
        net_resume,
        net_offline,
        net_online,
        net_remove,
        NULL,
        NULL,
        net_notify_event
};

/*
 * Module Interface Routines
 */

/*
 * rcm_mod_init()
 *
 *      Update registrations, and return the ops structure.
 */
struct rcm_mod_ops *
rcm_mod_init(void)
{
        dladm_status_t  status;
        char            errmsg[DLADM_STRSIZE];

        cache_head.next = &cache_tail;
        cache_head.prev = NULL;
        cache_tail.prev = &cache_head;
        cache_tail.next = NULL;
        (void) mutex_init(&cache_lock, USYNC_THREAD, NULL);

        if ((status = dladm_open(&dld_handle)) != DLADM_STATUS_OK) {
                rcm_log_message(RCM_WARNING,
                    "NET: mod_init failed: cannot open datalink handle: %s\n",
                    dladm_status2str(status, errmsg));
                return (NULL);
        }

        /* Return the ops vectors */
        return (&net_ops);
}

/*
 * rcm_mod_info()
 *
 *      Return a string describing this module.
 */
const char *
rcm_mod_info(void)
{
        return ("Network namespace module 1.13");
}

/*
 * rcm_mod_fini()
 *
 *      Destroy the cache.
 */
int
rcm_mod_fini(void)
{
        free_cache();
        (void) mutex_destroy(&cache_lock);

        dladm_close(dld_handle);
        return (RCM_SUCCESS);
}

/*
 * net_register()
 *
 *      Make sure the cache is properly sync'ed, and its registrations
 *      are in order.
 *
 *      Locking: the cache is locked by update_cache, and is held
 *      throughout update_cache's execution because it reads and
 *      possibly modifies cache links continuously.
 */
static int
net_register(rcm_handle_t *hd)
{
        update_cache(hd);
        /*
         * Need to register interest in all new resources
         * getting attached, so we get attach event notifications
         */
        if (!events_registered) {
                if (rcm_register_event(hd, RCM_RESOURCE_PHYSLINK_NEW, 0, NULL)
                    != RCM_SUCCESS) {
                        rcm_log_message(RCM_ERROR,
                            _("NET: failed to register %s\n"),
                            RCM_RESOURCE_PHYSLINK_NEW);
                        return (RCM_FAILURE);
                } else {
                        rcm_log_message(RCM_DEBUG, _("NET: registered %s \n"),
                            RCM_RESOURCE_PHYSLINK_NEW);
                        events_registered++;
                }
        }

        return (RCM_SUCCESS);
}

/*
 * net_unregister()
 *
 *      Manually walk through the cache, unregistering all the networks.
 *
 *      Locking: the cache is locked throughout the execution of this routine
 *      because it reads and modifies cache links continuously.
 */
static int
net_unregister(rcm_handle_t *hd)
{
        net_cache_t *probe;

        assert(hd != NULL);

        /* Walk the cache, unregistering everything */
        (void) mutex_lock(&cache_lock);
        probe = cache_head.next;
        while (probe != &cache_tail) {
                (void) rcm_unregister_interest(hd, probe->resource, 0);
                cache_remove(probe);
                free_node(probe);
                probe = cache_head.next;
        }
        (void) mutex_unlock(&cache_lock);

        /*
         * Need to unregister interest in all new resources
         */
        if (events_registered) {
                if (rcm_unregister_event(hd, RCM_RESOURCE_PHYSLINK_NEW, 0)
                    != RCM_SUCCESS) {
                        rcm_log_message(RCM_ERROR,
                            _("NET: failed to unregister %s\n"),
                            RCM_RESOURCE_PHYSLINK_NEW);
                        return (RCM_FAILURE);
                } else {
                        rcm_log_message(RCM_DEBUG, _("NET: unregistered %s\n"),
                            RCM_RESOURCE_PHYSLINK_NEW);
                        events_registered--;
                }
        }

        return (RCM_SUCCESS);
}

/*
 * Since all we do is pass operations thru, we provide a general
 * routine for passing through operations.
 */
/*ARGSUSED*/
static int
net_passthru(rcm_handle_t *hd, int op, const char *rsrc, uint_t flag,
    char **reason, rcm_info_t **dependent_reason, void *arg)
{
        net_cache_t     *node;
        char            *exported;
        datalink_id_t   linkid;
        int             len;
        int             rv;

        /*
         * Lock the cache just long enough to extract information about this
         * resource.
         */
        (void) mutex_lock(&cache_lock);
        node = cache_lookup(rsrc);
        if (!node) {
                rcm_log_message(RCM_WARNING,
                    _("NET: unrecognized resource %s\n"), rsrc);
                (void) mutex_unlock(&cache_lock);
                return (RCM_SUCCESS);
        }

        /*
         * Since node could be freed after we drop cache_lock, allocate a
         * stack-local copy. We don't use malloc() because some of the
         * operations (such as NET_REMOVE) are not allowed to fail. Note
         * that exported is never more than MAXPATHLEN bytes.
         */
        len = strlen("SUNW_datalink/") + LINKID_STR_WIDTH + 1;
        exported = alloca(len);
        linkid = node->linkid;
        (void) snprintf(exported, len, "SUNW_datalink/%u", linkid);

        /*
         * Remove notifications are unconditional in the RCM state model,
         * so it's safe to remove the node from the cache at this point.
         * And we need to remove it so that we will recognize it as a new
         * resource following the reattachment of the resource.
         */
        if (op == NET_REMOVE) {
                cache_remove(node);
                free_node(node);
        }
        (void) mutex_unlock(&cache_lock);

        switch (op) {
        case NET_SUSPEND:
                rv = rcm_request_suspend(hd, exported, flag,
                    (timespec_t *)arg, dependent_reason);
                break;
        case NET_OFFLINE:
                rv = rcm_request_offline(hd, exported, flag, dependent_reason);
                break;
        case NET_ONLINE:
                rv = rcm_notify_online(hd, exported, flag, dependent_reason);
                break;
        case NET_REMOVE:
                rv = rcm_notify_remove(hd, exported, flag, dependent_reason);
                if (rv == RCM_SUCCESS) {
                        rcm_log_message(RCM_DEBUG,
                            _("NET: mark link %d as removed\n"), linkid);

                        /*
                         * Delete active linkprop before this active link
                         * is deleted.
                         */
                        (void) dladm_set_linkprop(dld_handle, linkid, NULL,
                            NULL, 0, DLADM_OPT_ACTIVE);
                        (void) dladm_destroy_datalink_id(dld_handle, linkid,
                            DLADM_OPT_ACTIVE);
                }
                break;
        case NET_RESUME:
                rv = rcm_notify_resume(hd, exported, flag, dependent_reason);
                break;
        default:
                rcm_log_message(RCM_WARNING,
                    _("NET: bad RCM operation %1$d for %2$s\n"), op, exported);
                errno = EINVAL;
                return (RCM_FAILURE);
        }

        if (rv != RCM_SUCCESS) {
                char format[256];
                (void) snprintf(format, sizeof (format),
                    _("RCM operation on dependent %s did not succeed"),
                    exported);
                rcm_log_message(RCM_WARNING, "NET: %s\n", format);
        }
        return (rv);
}


/*
 * net_offline()
 *
 *      Determine dependents of the resource being offlined, and offline
 *      them all.
 */
static int
net_offline(rcm_handle_t *hd, char *rsrc, id_t id, uint_t flags,
    char **reason, rcm_info_t **dependent_reason)
{
        assert(hd != NULL);
        assert(rsrc != NULL);
        assert(id == (id_t)0);
        assert(reason != NULL);
        assert(dependent_reason != NULL);

        rcm_log_message(RCM_TRACE1, _("NET: offline(%s)\n"), rsrc);

        return (net_passthru(hd, NET_OFFLINE, rsrc, flags, reason,
            dependent_reason, NULL));
}

/*
 * net_online()
 *
 *      Online the previously offlined resource, and online its dependents.
 */
static int
net_online(rcm_handle_t *hd, char *rsrc, id_t id, uint_t flag, char **reason,
    rcm_info_t **dependent_reason)
{
        assert(hd != NULL);
        assert(rsrc != NULL);
        assert(id == (id_t)0);

        rcm_log_message(RCM_TRACE1, _("NET: online(%s)\n"), rsrc);

        return (net_passthru(hd, NET_ONLINE, rsrc, flag, reason,
            dependent_reason, NULL));
}

/*
 * net_getinfo()
 *
 *      Gather usage information for this resource.
 *
 *      Locking: the cache is locked while this routine looks up the
 *      resource and extracts copies of any piece of information it needs.
 *      The cache is then unlocked, and this routine performs the rest of
 *      its functions without touching any part of the cache.
 */
/*ARGSUSED*/
static int
net_getinfo(rcm_handle_t *hd, char *rsrc, id_t id, uint_t flag,
    char **info, char **errstr, nvlist_t *proplist, rcm_info_t **depend_info)
{
        int             len;
        dladm_status_t  status;
        char            link[MAXLINKNAMELEN];
        char            errmsg[DLADM_STRSIZE];
        char            *exported;
        const char      *info_fmt;
        net_cache_t     *node;

        assert(hd != NULL);
        assert(rsrc != NULL);
        assert(id == (id_t)0);
        assert(info != NULL);
        assert(depend_info != NULL);

        rcm_log_message(RCM_TRACE1, _("NET: getinfo(%s)\n"), rsrc);

        info_fmt = _("Network interface %s");

        (void) mutex_lock(&cache_lock);
        node = cache_lookup(rsrc);
        if (!node) {
                rcm_log_message(RCM_WARNING,
                    _("NET: unrecognized resource %s\n"), rsrc);
                (void) mutex_unlock(&cache_lock);
                errno = ENOENT;
                return (RCM_FAILURE);
        }

        len = strlen(info_fmt) + MAXLINKNAMELEN + 1;
        if ((status = dladm_datalink_id2info(dld_handle, node->linkid, NULL,
            NULL, NULL, link, sizeof (link))) != DLADM_STATUS_OK) {
                rcm_log_message(RCM_ERROR,
                    _("NET: usage(%s) get link name failure(%s)\n"),
                    node->resource, dladm_status2str(status, errmsg));
                (void) mutex_unlock(&cache_lock);
                return (RCM_FAILURE);
        } else if ((*info = (char *)malloc(len)) == NULL) {
                rcm_log_message(RCM_ERROR, _("NET: malloc failure"));
                (void) mutex_unlock(&cache_lock);
                return (RCM_FAILURE);
        }

        /* Fill in the string */
        (void) snprintf(*info, len, info_fmt, link);

        len = strlen("SUNW_datalink/") + LINKID_STR_WIDTH + 1;
        exported = malloc(len);
        if (!exported) {
                rcm_log_message(RCM_ERROR, _("NET: allocation failure"));
                free(*info);
                (void) mutex_unlock(&cache_lock);
                return (RCM_FAILURE);
        }
        (void) snprintf(exported, len, "SUNW_datalink/%u", node->linkid);
        (void) mutex_unlock(&cache_lock);

        /* Get dependent info if requested */
        if ((flag & RCM_INCLUDE_DEPENDENT) || (flag & RCM_INCLUDE_SUBTREE)) {
                (void) rcm_get_info(hd, exported, flag, depend_info);
        }

        (void) nvlist_add_string(proplist, RCM_CLIENT_NAME, "SunOS");
        (void) nvlist_add_string_array(proplist, RCM_CLIENT_EXPORTS,
            &exported, 1);

        free(exported);
        return (RCM_SUCCESS);
}

/*
 * net_suspend()
 *
 *      Notify all dependents that the resource is being suspended.
 *      Since no real operation is involved, QUERY or not doesn't matter.
 *
 *      Locking: the cache is only used to retrieve some information about
 *      this resource, so it is only locked during that retrieval.
 */
static int
net_suspend(rcm_handle_t *hd, char *rsrc, id_t id, timespec_t *interval,
    uint_t flag, char **reason, rcm_info_t **dependent_reason)
{
        assert(hd != NULL);
        assert(rsrc != NULL);
        assert(id == (id_t)0);
        assert(interval != NULL);
        assert(reason != NULL);
        assert(dependent_reason != NULL);

        rcm_log_message(RCM_TRACE1, _("NET: suspend(%s)\n"), rsrc);

        return (net_passthru(hd, NET_SUSPEND, rsrc, flag, reason,
            dependent_reason, (void *)interval));
}

/*
 * net_resume()
 *
 *      Resume all the dependents of a suspended network.
 *
 *      Locking: the cache is only used to retrieve some information about
 *      this resource, so it is only locked during that retrieval.
 */
static int
net_resume(rcm_handle_t *hd, char *rsrc, id_t id, uint_t flag, char **info,
    rcm_info_t **dependent_info)
{
        assert(hd != NULL);
        assert(rsrc != NULL);
        assert(id == (id_t)0);
        assert(info != NULL);
        assert(dependent_info != NULL);

        rcm_log_message(RCM_TRACE1, _("NET: resume(%s)\n"), rsrc);

        return (net_passthru(hd, NET_RESUME, rsrc, flag, info, dependent_info,
            NULL));
}

/*
 * net_remove()
 *
 *      This is another NO-OP for us, we just passthru the information.  We
 *      don't need to remove it from our cache.  We don't unregister
 *      interest at this point either; the network device name is still
 *      around.  This way we don't have to change this logic when we
 *      gain the ability to learn about DR attach operations.
 */
static int
net_remove(rcm_handle_t *hd, char *rsrc, id_t id, uint_t flag, char **info,
    rcm_info_t **dependent_info)
{
        assert(hd != NULL);
        assert(rsrc != NULL);
        assert(id == (id_t)0);
        assert(info != NULL);
        assert(dependent_info != NULL);

        rcm_log_message(RCM_TRACE1, _("NET: remove(%s)\n"), rsrc);

        return (net_passthru(hd, NET_REMOVE, rsrc, flag, info, dependent_info,
            NULL));
}

/*
 * Cache management routines.  Note that the cache is implemented as a
 * trivial linked list, and is only required because RCM doesn't
 * provide enough state about our own registrations back to us.  This
 * linked list implementation probably clobbers the CPU cache pretty
 * well.
 */

/*
 * cache_lookup()
 *
 * Get a cache node for a resource.  Call with cache lock held.
 */
static net_cache_t *
cache_lookup(const char *resource)
{
        net_cache_t *probe;
        probe = cache_head.next;
        while (probe != &cache_tail) {
                if (probe->resource &&
                    (strcmp(resource, probe->resource) == 0)) {
                        return (probe);
                }
                probe = probe->next;
        }
        return (NULL);
}

/*
 * free_node()
 *
 * Free a node.  Make sure it isn't in the list!
 */
static void
free_node(net_cache_t *node)
{
        if (node) {
                free(node->resource);
                free(node);
        }
}

/*
 * cache_insert()
 *
 * Call with the cache_lock held.
 */
static void
cache_insert(net_cache_t *node)
{
        /* insert at the head for best performance */
        node->next = cache_head.next;
        node->prev = &cache_head;

        node->next->prev = node;
        node->prev->next = node;
}

/*
 * cache_remove()
 *
 * Call with the cache_lock held.
 */
static void
cache_remove(net_cache_t *node)
{
        node->next->prev = node->prev;
        node->prev->next = node->next;
        node->next = NULL;
        node->prev = NULL;
}

/*
 * devfs_entry()
 *
 * Call with the cache_lock held.
 */
/*ARGSUSED*/
static int
devfs_entry(di_node_t node, di_minor_t minor, void *arg)
{
        char            *devfspath;
        char            resource[MAXPATHLEN];
        char            dev[MAXNAMELEN];
        datalink_id_t   linkid;
        char            *drv;
        char            *cp;
        net_cache_t     *probe;

        cp = di_minor_nodetype(minor);
        if ((cp == NULL) || (strcmp(cp, DDI_NT_NET))) {
                /* doesn't look like a network device */
                return (DI_WALK_CONTINUE);
        }

        drv = di_driver_name(node);
        if (drv == NULL) {
                /* what else can we do? */
                return (DI_WALK_CONTINUE);
        }

        devfspath = di_devfs_path(node);
        if (!devfspath) {
                /* no devfs path?!? */
                rcm_log_message(RCM_DEBUG, _("NET: missing devfs path\n"));
                return (DI_WALK_CONTINUE);
        }

        if (strncmp("/pseudo", devfspath, strlen("/pseudo")) == 0) {
                /* ignore pseudo devices, probably not really NICs */
                rcm_log_message(RCM_DEBUG,
                    _("NET: ignoring pseudo device %s\n"), devfspath);
                di_devfs_path_free(devfspath);
                return (DI_WALK_CONTINUE);
        }

        (void) snprintf(resource, sizeof (resource), "/devices%s", devfspath);
        di_devfs_path_free(devfspath);

        (void) snprintf(dev, sizeof (dev), "%s%d", drv, di_instance(node));
        if (dladm_dev2linkid(dld_handle, dev, &linkid) != DLADM_STATUS_OK) {
                rcm_log_message(RCM_DEBUG,
                    _("NET: failed to find the linkid for %s\n"), dev);
                return (DI_WALK_CONTINUE);
        }

        probe = cache_lookup(resource);
        if (probe != NULL) {
                rcm_log_message(RCM_DEBUG,
                    _("NET: %s already registered (linkid %u)\n"),
                    resource, linkid);
                probe->linkid = linkid;
                probe->flags &= ~(CACHE_STALE);
        } else {
                rcm_log_message(RCM_DEBUG,
                    _("NET: %s is new resource (linkid %u)\n"),
                    resource, linkid);
                probe = calloc(1, sizeof (net_cache_t));
                if (!probe) {
                        rcm_log_message(RCM_ERROR, _("NET: malloc failure"));
                        return (DI_WALK_CONTINUE);
                }

                probe->resource = strdup(resource);
                probe->linkid = linkid;

                if (!probe->resource) {
                        free_node(probe);
                        return (DI_WALK_CONTINUE);
                }

                probe->flags |= CACHE_NEW;
                cache_insert(probe);
        }

        return (DI_WALK_CONTINUE);
}

/*
 * update_cache()
 *
 * The devinfo tree walking code is lifted from ifconfig.c.
 */
static void
update_cache(rcm_handle_t *hd)
{
        net_cache_t     *probe;
        di_node_t       root;
        int             rv;

        (void) mutex_lock(&cache_lock);

        /* first we walk the entire cache, marking each entry stale */
        probe = cache_head.next;
        while (probe != &cache_tail) {
                probe->flags |= CACHE_STALE;
                probe = probe->next;
        }

        root = di_init("/", DINFOSUBTREE | DINFOMINOR);
        if (root == DI_NODE_NIL) {
                goto done;
        }

        (void) di_walk_minor(root, DDI_NT_NET, DI_CHECK_ALIAS, NULL,
            devfs_entry);

        di_fini(root);

        probe = cache_head.next;
        while (probe != &cache_tail) {
                net_cache_t *freeit;
                if (probe->flags & CACHE_STALE) {
                        (void) rcm_unregister_interest(hd, probe->resource, 0);
                        rcm_log_message(RCM_DEBUG, _("NET: unregistered %s\n"),
                            probe->resource);
                        freeit = probe;
                        probe = probe->next;
                        cache_remove(freeit);
                        free_node(freeit);
                        continue;
                }

                if (!(probe->flags & CACHE_NEW)) {
                        probe = probe->next;
                        continue;
                }

                rcm_log_message(RCM_DEBUG, _("NET: registering %s\n"),
                    probe->resource);
                rv = rcm_register_interest(hd, probe->resource, 0, NULL);
                if (rv != RCM_SUCCESS) {
                        rcm_log_message(RCM_ERROR,
                            _("NET: failed to register %s\n"),
                            probe->resource);
                } else {
                        rcm_log_message(RCM_DEBUG,
                            _("NET: registered %s as SUNW_datalink/%u\n"),
                            probe->resource, probe->linkid);
                        probe->flags &= ~(CACHE_NEW);
                }
                probe = probe->next;
        }

done:
        (void) mutex_unlock(&cache_lock);
}

/*
 * free_cache()
 */
static void
free_cache(void)
{
        net_cache_t *probe;

        (void) mutex_lock(&cache_lock);
        probe = cache_head.next;
        while (probe != &cache_tail) {
                cache_remove(probe);
                free_node(probe);
                probe = cache_head.next;
        }
        (void) mutex_unlock(&cache_lock);
}

/*
 * net_notify_event - Project private implementation to receive new
 *                      resource events. It intercepts all new resource
 *                      events. If the new resource is a network resource,
 *                      update the physical link cache.
 */
/*ARGSUSED*/
static int
net_notify_event(rcm_handle_t *hd, char *rsrc, id_t id, uint_t flags,
    char **errorp, nvlist_t *nvl, rcm_info_t **depend_info)
{
        nvpair_t        *nvp = NULL;
        uint64_t        id64 = (uint64_t)DATALINK_INVALID_LINKID;
        boolean_t       reconfigured = B_FALSE;

        rcm_log_message(RCM_TRACE1, _("NET: notify_event(%s)\n"), rsrc);

        if (strcmp(rsrc, RCM_RESOURCE_PHYSLINK_NEW) != 0) {
                rcm_log_message(RCM_INFO,
                    _("NET: unrecognized event for %s\n"), rsrc);
                errno = EINVAL;
                return (RCM_FAILURE);
        }

        /* Update cache to reflect latest physical links */
        update_cache(hd);

        while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) {
                if (strcmp(nvpair_name(nvp), RCM_NV_RECONFIGURED) == 0) {
                        if (nvpair_value_boolean_value(nvp,
                            &reconfigured) != 0) {
                                rcm_log_message(RCM_INFO,
                                    _("NET: unrecognized %s event data\n"),
                                    RCM_NV_RECONFIGURED);
                                errno = EINVAL;
                                return (RCM_FAILURE);
                        }

                        rcm_log_message(RCM_TRACE1,
                            "NET: %s event data (%sreconfiguration)\n",
                            RCM_NV_RECONFIGURED, reconfigured ? "" : "not ");
                }

                if (strcmp(nvpair_name(nvp), RCM_NV_LINKID) == 0) {
                        if (nvpair_value_uint64(nvp, &id64) != 0) {
                                rcm_log_message(RCM_INFO,
                                    _("NET: unrecognized %s event data\n"),
                                    RCM_NV_LINKID);
                                errno = EINVAL;
                                return (RCM_FAILURE);
                        }

                        rcm_log_message(RCM_TRACE1,
                            "NET: %s event data (linkid %d)\n", RCM_NV_LINKID,
                            (datalink_id_t)id64);
                }
        }

        if ((datalink_id_t)id64 == DATALINK_INVALID_LINKID) {
                rcm_log_message(RCM_INFO, _("NET: invalid datalink\n"));
                errno = EINVAL;
                return (RCM_FAILURE);
        }

        /*
         * If this is device reconfiguration, populate the LINK_NEW event
         * to start the DR process.
         */
        if (reconfigured) {
                nvlist_t *nnvl = NULL;

                rcm_log_message(RCM_TRACE1,
                    "NET: reconfigured data-link (id %d)\n",
                    (datalink_id_t)id64);

                if ((nvlist_alloc(&nnvl, 0, 0) != 0) || (nvlist_add_uint64(nnvl,
                    RCM_NV_LINKID, id64) != 0) || (rcm_notify_event(hd,
                    RCM_RESOURCE_LINK_NEW, 0, nnvl, NULL) != RCM_SUCCESS)) {
                        nvlist_free(nnvl);
                        rcm_log_message(RCM_INFO,
                            _("NET: notify %s event failed\n"),
                            RCM_RESOURCE_LINK_NEW);
                        errno = EINVAL;
                        return (RCM_FAILURE);
                }
                nvlist_free(nnvl);
        }

        rcm_log_message(RCM_TRACE1,
            _("NET: notify_event: device configuration complete\n"));

        return (RCM_SUCCESS);
}