/*
 * 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) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <limits.h>
#include <strings.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <alloca.h>
#include <devid.h>
#include <sys/stat.h>
#include <libnvpair.h>
#include <fm/topo_mod.h>
#include <fm/fmd_fmri.h>
#include <sys/fm/protocol.h>

#include <topo_method.h>
#include <topo_subr.h>
#include <dev.h>

static int dev_enum(topo_mod_t *, tnode_t *, const char *, topo_instance_t,
    topo_instance_t, void *, void *);
static void dev_release(topo_mod_t *, tnode_t *);
static int dev_fmri_nvl2str(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);
static int dev_fmri_str2nvl(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);
static int dev_fmri_create_meth(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);
static int dev_fmri_present(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);
static int dev_fmri_replaced(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);
static int dev_fmri_unusable(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);
static int dev_fmri_service_state(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);

static const topo_method_t dev_methods[] = {
        { TOPO_METH_NVL2STR, TOPO_METH_NVL2STR_DESC, TOPO_METH_NVL2STR_VERSION,
            TOPO_STABILITY_INTERNAL, dev_fmri_nvl2str },
        { TOPO_METH_STR2NVL, TOPO_METH_STR2NVL_DESC, TOPO_METH_STR2NVL_VERSION,
            TOPO_STABILITY_INTERNAL, dev_fmri_str2nvl },
        { TOPO_METH_FMRI, TOPO_METH_FMRI_DESC, TOPO_METH_FMRI_VERSION,
            TOPO_STABILITY_INTERNAL, dev_fmri_create_meth },
        { TOPO_METH_PRESENT, TOPO_METH_PRESENT_DESC, TOPO_METH_PRESENT_VERSION,
            TOPO_STABILITY_INTERNAL, dev_fmri_present },
        { TOPO_METH_REPLACED, TOPO_METH_REPLACED_DESC,
            TOPO_METH_REPLACED_VERSION, TOPO_STABILITY_INTERNAL,
            dev_fmri_replaced },
        { TOPO_METH_UNUSABLE, TOPO_METH_UNUSABLE_DESC,
            TOPO_METH_UNUSABLE_VERSION, TOPO_STABILITY_INTERNAL,
            dev_fmri_unusable },
        { TOPO_METH_SERVICE_STATE, TOPO_METH_SERVICE_STATE_DESC,
            TOPO_METH_SERVICE_STATE_VERSION, TOPO_STABILITY_INTERNAL,
            dev_fmri_service_state },
        { NULL }
};

static const topo_modops_t dev_ops =
        { dev_enum, dev_release };
static const topo_modinfo_t dev_info =
        { "dev", FM_FMRI_SCHEME_DEV, DEV_VERSION, &dev_ops };

int
dev_init(topo_mod_t *mod, topo_version_t version)
{
        if (getenv("TOPOHCDEBUG"))
                topo_mod_setdebug(mod);
        topo_mod_dprintf(mod, "initializing dev builtin\n");

        if (version != DEV_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (topo_mod_register(mod, &dev_info, TOPO_VERSION) != 0) {
                topo_mod_dprintf(mod, "failed to register dev_info: "
                    "%s\n", topo_mod_errmsg(mod));
                return (-1);
        }

        return (0);
}

void
dev_fini(topo_mod_t *mod)
{
        topo_mod_unregister(mod);
}

/*ARGSUSED*/
static int
dev_enum(topo_mod_t *mod, tnode_t *pnode, const char *name,
    topo_instance_t min, topo_instance_t max, void *notused1, void *notused2)
{
        /*
         * Methods are registered, but there is no enumeration.  Should
         * enumeration be added be sure to cater for global vs non-global
         * zones.
         */
        (void) topo_method_register(mod, pnode, dev_methods);
        return (0);
}

static void
dev_release(topo_mod_t *mod, tnode_t *node)
{
        topo_method_unregister_all(mod, node);
}

static ssize_t
fmri_nvl2str(nvlist_t *nvl, char *buf, size_t buflen)
{
        char *devid = NULL, *tpl0id = NULL;
        char *devpath = NULL;
        ssize_t size = 0;
        uint8_t version;
        int err;

        if (nvlist_lookup_uint8(nvl, FM_VERSION, &version) != 0 ||
            version > FM_DEV_SCHEME_VERSION)
                return (-1);

        /* Get devid, if present */
        err = nvlist_lookup_string(nvl, FM_FMRI_DEV_ID, &devid);
        if (err != 0 && err != ENOENT)
                return (-1);

        /* Get target-port-l0id, if present */
        err = nvlist_lookup_string(nvl, FM_FMRI_DEV_TGTPTLUN0, &tpl0id);
        if (err != 0 && err != ENOENT)
                return (-1);

        /* There must be a device path present */
        err = nvlist_lookup_string(nvl, FM_FMRI_DEV_PATH, &devpath);
        if (err != 0 || devpath == NULL)
                return (-1);

        /*
         * dev:///
         *
         * The dev scheme does not render fmri authority information
         * in the string form of an fmri.  It is meaningless to
         * transmit a dev scheme fmri outside of the immediate fault
         * manager.
         */
        topo_fmristr_build(&size,
            buf, buflen, FM_FMRI_SCHEME_DEV, NULL, ":///");

        /* device-id part, topo_fmristr_build does nothing if devid is NULL */
        topo_fmristr_build(&size,
            buf, buflen, devid, ":" FM_FMRI_DEV_ID "=", NULL);

        /* target-port-l0id part */
        topo_fmristr_build(&size,
            buf, buflen, tpl0id, ":" FM_FMRI_DEV_TGTPTLUN0 "=", NULL);

        /*
         * device-path part; the devpath should always start with a /
         * so you'd think we don't need to add a further / prefix here;
         * however past implementation has always added the / if
         * there is a devid component so we continue to do that
         * so strings match exactly as before.  So we can have:
         *
         *      dev:////pci@0,0/...
         *      dev:///<devid-and-tpl0>//pci@0,0/...
         *
         *      where <devid-and-tpl0> =
         *                      [:devid=<devid>][:target-port-l0id=<tpl0>]
         */
        topo_fmristr_build(&size, buf, buflen, devpath,
            devid || tpl0id ? "/" : NULL, NULL);

        return (size);
}

/*ARGSUSED*/
static int
dev_fmri_nvl2str(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *nvl, nvlist_t **out)
{
        ssize_t len;
        char *name = NULL;
        nvlist_t *fmristr;

        if (version > TOPO_METH_NVL2STR_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if ((len = fmri_nvl2str(nvl, NULL, 0)) == 0 ||
            (name = topo_mod_alloc(mod, len + 1)) == NULL ||
            fmri_nvl2str(nvl, name, len + 1) == 0) {
                if (name != NULL)
                        topo_mod_free(mod, name, len + 1);
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
        }

        if (topo_mod_nvalloc(mod, &fmristr, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
        if (nvlist_add_string(fmristr, "fmri-string", name) != 0) {
                topo_mod_free(mod, name, len + 1);
                nvlist_free(fmristr);
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
        }
        topo_mod_free(mod, name, len + 1);
        *out = fmristr;

        return (0);
}

/*ARGSUSED*/
static int
dev_fmri_str2nvl(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        char *cur, *devid = NULL, *tpl0id = NULL;
        char *str, *strcp;
        nvlist_t *fmri;
        char *devpath;
        size_t len;
        int err;

        if (version > TOPO_METH_STR2NVL_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (nvlist_lookup_string(in, "fmri-string", &str) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));

        len = strlen(str);

        /*
         * We're expecting a string version of a dev scheme FMRI, and
         * no fmri authority information.
         *
         * The shortest legal string would be "dev:////" (len 8) for a string
         * with no FMRI auth info, no devid or target-port-l0id and
         * an empty devpath string.
         */
        if (len < 8 || strncmp(str, "dev:///", 7) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        strcp = alloca(len + 1);
        (void) memcpy(strcp, str, len);
        strcp[len] = '\0';
        cur = strcp + 7;        /* already parsed "dev:///" */

        /*
         * If the first character after the "/" that terminates the (empty)
         * fmri authority is a colon then we have devid and/or target-port-l0id
         * info.  They could be in either order.
         *
         * If not a colon then it must be the / that begins the devpath.
         */
        if (*cur == ':') {
                char *eos, *part[2];
                int i;
                /*
                 * Look ahead to the "/" that starts the devpath.  If not
                 * found or if straight after the : then we're busted.
                 */
                eos = devpath = strchr(cur, '/');
                if (devpath == NULL || devpath == cur + 1)
                        return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

                part[0] = ++cur;

                /*
                 * Replace the initial "/" of the devpath with a NUL
                 * to terminate the string before it.  We'll undo this
                 * before rendering devpath.
                 */
                *eos = '\0';

                /*
                 * We should now have a NUL-terminated string matching
                 * foo=<pat1>[:bar=<pat2>] (we stepped over the initial :)
                 * Look for a second colon; if found there must be space
                 * after it for the additional component, but no more colons.
                 */
                if ((part[1] = strchr(cur, ':')) != NULL) {
                        if (part[1] + 1 == eos ||
                            strchr(part[1] + 1, ':') != NULL)
                                return (topo_mod_seterrno(mod,
                                    EMOD_FMRI_MALFORM));
                        *part[1] = '\0'; /* terminate part[0] */
                        part[1]++;
                }

                for (i = 0; i < 2; i++) {
                        char *eq;

                        if (!part[i])
                                continue;

                        if ((eq = strchr(part[i], '=')) == NULL ||
                            *(eq + 1) == '\0')
                                return (topo_mod_seterrno(mod,
                                    EMOD_FMRI_MALFORM));

                        *eq = '\0';
                        if (strcmp(part[i], FM_FMRI_DEV_ID) == 0)
                                devid = eq + 1;
                        else if (strcmp(part[i], FM_FMRI_DEV_TGTPTLUN0) == 0)
                                tpl0id = eq + 1;
                        else
                                return (topo_mod_seterrno(mod,
                                    EMOD_FMRI_MALFORM));
                }

                if (devid == NULL && tpl0id == NULL)
                        return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

                cur = devpath;  /* initial slash is NULled */
        } else if (*cur != '/') {
                /* the device-path should start with a slash */
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));
        } else {
                devpath = cur;
        }

        if (topo_mod_nvalloc(mod, &fmri, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));

        err = nvlist_add_uint8(fmri, FM_VERSION, FM_DEV_SCHEME_VERSION);
        err |= nvlist_add_string(fmri, FM_FMRI_SCHEME, FM_FMRI_SCHEME_DEV);

        if (devid != NULL)
                err |= nvlist_add_string(fmri, FM_FMRI_DEV_ID, devid);

        if (tpl0id != NULL)
                err |= nvlist_add_string(fmri, FM_FMRI_DEV_TGTPTLUN0, tpl0id);

        if (devid != NULL || tpl0id != NULL)
                *devpath = '/'; /* we NULed this earlier; put it back */

        /* step over repeated initial / in the devpath */
        while (*(devpath + 1) == '/')
                devpath++;

        err |= nvlist_add_string(fmri, FM_FMRI_DEV_PATH, devpath);

        if (err != 0) {
                nvlist_free(fmri);
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
        }

        *out = fmri;

        return (0);
}

/*ARGSUSED*/
static int
dev_fmri_present(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        uint8_t fmversion;
        char *devpath = NULL;
        uint32_t present;
        char *devid = NULL, *path;
        ddi_devid_t id;
        ddi_devid_t matchid;
        di_node_t dnode;
        struct stat sb;
        int len;

        if (version > TOPO_METH_PRESENT_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (nvlist_lookup_uint8(in, FM_VERSION, &fmversion) != 0 ||
            fmversion > FM_DEV_SCHEME_VERSION ||
            nvlist_lookup_string(in, FM_FMRI_DEV_PATH, &devpath) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        (void) nvlist_lookup_string(in, FM_FMRI_DEV_ID, &devid);

        if (devpath == NULL || strlen(devpath) == 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        /*
         * stat() the device node in devfs. This will tell us if the device is
         * present or not. Don't stat the minor,  just the whole device.
         * If the device is present and there is a devid, it must also match.
         * so di_init that one node. No need for DINFOFORCE.
         */
        len = strlen(devpath) + strlen("/devices") + 1;
        path = topo_mod_alloc(mod, len);
        (void) snprintf(path, len, "/devices%s", devpath);
        if (devid == NULL) {
                if (stat(path, &sb) != -1)
                        present = 1;
                else if ((dnode = di_init("/", DINFOCACHE)) == DI_NODE_NIL)
                        present = 0;
                else {
                        if (di_lookup_node(dnode, devpath) == DI_NODE_NIL)
                                present = 0;
                        else
                                present = 1;
                        di_fini(dnode);
                }
        } else {
                if (stat(path, &sb) == -1)
                        present = 0;
                else if ((dnode = di_init(devpath, DINFOCPYONE)) == DI_NODE_NIL)
                        present = 0;
                else {
                        if ((id = di_devid(dnode)) == NULL ||
                            devid_str_decode(devid, &matchid, NULL) != 0)
                                present = 0;
                        else {
                                if (devid_compare(id, matchid) != 0)
                                        present = 0;
                                else
                                        present = 1;
                                devid_free(matchid);
                        }
                        di_fini(dnode);
                }
        }
        topo_mod_free(mod, path, len);

        if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        if (nvlist_add_uint32(*out, TOPO_METH_PRESENT_RET, present) != 0) {
                nvlist_free(*out);
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        }

        return (0);
}

/*ARGSUSED*/
static int
dev_fmri_replaced(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        uint8_t fmversion;
        char *devpath = NULL;
        uint32_t rval;
        char *devid = NULL, *path;
        ddi_devid_t id;
        ddi_devid_t matchid;
        di_node_t dnode;
        struct stat sb;
        int len;

        if (version > TOPO_METH_REPLACED_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (nvlist_lookup_uint8(in, FM_VERSION, &fmversion) != 0 ||
            fmversion > FM_DEV_SCHEME_VERSION ||
            nvlist_lookup_string(in, FM_FMRI_DEV_PATH, &devpath) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        (void) nvlist_lookup_string(in, FM_FMRI_DEV_ID, &devid);

        if (devpath == NULL || strlen(devpath) == 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        /*
         * stat() the device node in devfs. This will tell us if the device is
         * present or not. Don't stat the minor,  just the whole device.
         * If the device is present and there is a devid, it must also match.
         * so di_init that one node. No need for DINFOFORCE.
         */
        len = strlen(devpath) + strlen("/devices") + 1;
        path = topo_mod_alloc(mod, len);
        (void) snprintf(path, len, "/devices%s", devpath);
        if (devid == NULL) {
                if (stat(path, &sb) != -1)
                        rval = FMD_OBJ_STATE_UNKNOWN;
                else if ((dnode = di_init("/", DINFOCACHE)) == DI_NODE_NIL)
                        rval = FMD_OBJ_STATE_UNKNOWN;
                else {
                        if (di_lookup_node(dnode, devpath) == DI_NODE_NIL)
                                rval = FMD_OBJ_STATE_UNKNOWN;
                        else
                                rval = FMD_OBJ_STATE_UNKNOWN;
                        di_fini(dnode);
                }
        } else {
                if (stat(path, &sb) == -1)
                        rval = FMD_OBJ_STATE_UNKNOWN;
                else if ((dnode = di_init(devpath, DINFOCPYONE)) == DI_NODE_NIL)
                        rval = FMD_OBJ_STATE_UNKNOWN;
                else {
                        if ((id = di_devid(dnode)) == NULL ||
                            devid_str_decode(devid, &matchid, NULL) != 0)
                                rval = FMD_OBJ_STATE_UNKNOWN;
                        else {
                                if (devid_compare(id, matchid) != 0)
                                        rval = FMD_OBJ_STATE_REPLACED;
                                else
                                        rval = FMD_OBJ_STATE_STILL_PRESENT;
                                devid_free(matchid);
                        }
                        di_fini(dnode);
                }
        }
        topo_mod_free(mod, path, len);

        if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        if (nvlist_add_uint32(*out, TOPO_METH_REPLACED_RET, rval) != 0) {
                nvlist_free(*out);
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        }

        return (0);
}

/*ARGSUSED*/
static int
dev_fmri_unusable(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        di_node_t dnode;
        uint8_t fmversion;
        char *devpath = NULL;
        uint32_t unusable;
        uint_t state;

        if (version > TOPO_METH_UNUSABLE_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (nvlist_lookup_uint8(in, FM_VERSION, &fmversion) != 0 ||
            fmversion > FM_DEV_SCHEME_VERSION ||
            nvlist_lookup_string(in, FM_FMRI_DEV_PATH, &devpath) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        if (devpath == NULL)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        if ((dnode = di_init(devpath, DINFOCPYONE)) == DI_NODE_NIL) {
                if (errno != ENXIO)
                        return (topo_mod_seterrno(mod, EMOD_UKNOWN_ENUM));
                unusable = 1;
        } else {
                uint_t retired = di_retired(dnode);
                state = di_state(dnode);
                if (retired || (state & (DI_DEVICE_OFFLINE | DI_DEVICE_DOWN |
                    DI_BUS_QUIESCED | DI_BUS_DOWN)))
                        unusable = 1;
                else
                        unusable = 0;
                di_fini(dnode);
        }

        if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        if (nvlist_add_uint32(*out, TOPO_METH_UNUSABLE_RET, unusable) != 0) {
                nvlist_free(*out);
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        }

        return (0);
}

/*ARGSUSED*/
static int
dev_fmri_service_state(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        di_node_t dnode;
        uint8_t fmversion;
        char *devpath = NULL;
        uint32_t service_state;
        uint_t state;

        if (version > TOPO_METH_SERVICE_STATE_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (nvlist_lookup_uint8(in, FM_VERSION, &fmversion) != 0 ||
            fmversion > FM_DEV_SCHEME_VERSION ||
            nvlist_lookup_string(in, FM_FMRI_DEV_PATH, &devpath) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        if (devpath == NULL)
                return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));

        if ((dnode = di_init(devpath, DINFOCPYONE)) == DI_NODE_NIL) {
                if (errno != ENXIO)
                        return (topo_mod_seterrno(mod, EMOD_UKNOWN_ENUM));
                service_state = FMD_SERVICE_STATE_UNUSABLE;
        } else {
                uint_t retired = di_retired(dnode);
                state = di_state(dnode);
                if (retired || (state & (DI_DEVICE_OFFLINE | DI_DEVICE_DOWN |
                    DI_BUS_QUIESCED | DI_BUS_DOWN)))
                        service_state = FMD_SERVICE_STATE_UNUSABLE;
                else if (state & DI_DEVICE_DEGRADED)
                        service_state = FMD_SERVICE_STATE_DEGRADED;
                else
                        service_state = FMD_SERVICE_STATE_OK;
                di_fini(dnode);
        }

        if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        if (nvlist_add_uint32(*out, TOPO_METH_SERVICE_STATE_RET,
            service_state) != 0) {
                nvlist_free(*out);
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        }

        return (0);
}

static nvlist_t *
dev_fmri_create(topo_mod_t *mp, const char *id, const char *path)
{
        nvlist_t *out = NULL;
        int e;

        if (topo_mod_nvalloc(mp, &out, NV_UNIQUE_NAME) != 0) {
                (void) topo_mod_seterrno(mp, EMOD_FMRI_NVL);
                return (NULL);
        }
        e = nvlist_add_string(out, FM_FMRI_SCHEME, FM_FMRI_SCHEME_DEV);
        e |= nvlist_add_uint8(out, FM_VERSION, FM_DEV_SCHEME_VERSION);
        e |= nvlist_add_string(out, FM_FMRI_DEV_PATH, path);

        if (id != NULL)
                e |= nvlist_add_string(out, FM_FMRI_DEV_ID, id);

        if (e == 0)
                return (out);

        topo_mod_dprintf(mp, "construction of dev nvl failed");
        (void) topo_mod_seterrno(mp, EMOD_FMRI_NVL);
        nvlist_free(out);
        return (NULL);
}

/*ARGSUSED*/
static int
dev_fmri_create_meth(topo_mod_t *mp, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        nvlist_t *args = NULL;
        char *path, *id = NULL;

        if (version > TOPO_METH_FMRI_VERSION)
                return (topo_mod_seterrno(mp, EMOD_VER_NEW));

        if (nvlist_lookup_nvlist(in, TOPO_METH_FMRI_ARG_NVL, &args) != 0 ||
            nvlist_lookup_string(args, FM_FMRI_DEV_PATH, &path) != 0) {
                topo_mod_dprintf(mp, "no path string in method argument\n");
                return (topo_mod_seterrno(mp, EMOD_METHOD_INVAL));
        }

        (void) nvlist_lookup_string(args, FM_FMRI_DEV_ID, &id);

        if ((*out = dev_fmri_create(mp, id, path)) == NULL)
                return (-1);
        return (0);
}