xref: /titanic_41/usr/src/lib/fm/topo/libtopo/common/svc.c (revision 8475e04352e630e4bd0f59a283286ee2475a14ce)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * This provides the basic mechanisms (str2nvl and nvl2str) for dealing with
29  * the service schema.  The official version of a svc FMRI has the form:
30  *
31  * 	svc://[scope@][system-fqn]/service[:instance][@contract-id]
32  *
33  * Where 'service' is a slash-delimited list of names.  Of these fields, the
34  * scope, constract-id, and system-fqn are rarely used, leaving the much more
35  * common form such as:
36  *
37  * 	svc:///network/ssh:default
38  *
39  * Note that the SMF software typically uses a shorthard form, where the
40  * authority is elided (svc:/network/ssh:default).  As this module deals with
41  * FMA FMRIs, we only support fully specified FMRIs.
42  *
43  * This module does not support enumeration, but implements methods for FMRI
44  * state (present, unusable, service state, and replaced).
45  */
46 
47 #include <fm/topo_mod.h>
48 #include <fm/fmd_fmri.h>
49 #include <sys/fm/protocol.h>
50 #include <topo_method.h>
51 #include <topo_subr.h>
52 #include <alloca.h>
53 #include <assert.h>
54 #include <svc.h>
55 #include <strings.h>
56 #include <libscf.h>
57 
58 static int svc_fmri_nvl2str(topo_mod_t *, tnode_t *, topo_version_t,
59     nvlist_t *, nvlist_t **);
60 static int svc_fmri_str2nvl(topo_mod_t *, tnode_t *, topo_version_t,
61     nvlist_t *, nvlist_t **);
62 static int svc_fmri_present(topo_mod_t *, tnode_t *, topo_version_t,
63     nvlist_t *, nvlist_t **);
64 static int svc_fmri_replaced(topo_mod_t *, tnode_t *, topo_version_t,
65     nvlist_t *, nvlist_t **);
66 static int svc_fmri_service_state(topo_mod_t *, tnode_t *, topo_version_t,
67     nvlist_t *, nvlist_t **);
68 static int svc_fmri_unusable(topo_mod_t *, tnode_t *, topo_version_t,
69     nvlist_t *, nvlist_t **);
70 static int svc_enum(topo_mod_t *, tnode_t *, const char *, topo_instance_t,
71     topo_instance_t, void *, void *);
72 static void svc_release(topo_mod_t *, tnode_t *);
73 
74 static const topo_method_t svc_methods[] = {
75 	{ TOPO_METH_NVL2STR, TOPO_METH_NVL2STR_DESC, TOPO_METH_NVL2STR_VERSION,
76 	    TOPO_STABILITY_INTERNAL, svc_fmri_nvl2str },
77 	{ TOPO_METH_STR2NVL, TOPO_METH_STR2NVL_DESC, TOPO_METH_STR2NVL_VERSION,
78 	    TOPO_STABILITY_INTERNAL, svc_fmri_str2nvl },
79 	{ TOPO_METH_PRESENT, TOPO_METH_PRESENT_DESC, TOPO_METH_PRESENT_VERSION,
80 	    TOPO_STABILITY_INTERNAL, svc_fmri_present },
81 	{ TOPO_METH_REPLACED, TOPO_METH_REPLACED_DESC,
82 	    TOPO_METH_REPLACED_VERSION, TOPO_STABILITY_INTERNAL,
83 	    svc_fmri_replaced },
84 	{ TOPO_METH_SERVICE_STATE, TOPO_METH_SERVICE_STATE_DESC,
85 	    TOPO_METH_SERVICE_STATE_VERSION, TOPO_STABILITY_INTERNAL,
86 	    svc_fmri_service_state },
87 	{ TOPO_METH_UNUSABLE, TOPO_METH_UNUSABLE_DESC,
88 	    TOPO_METH_UNUSABLE_VERSION, TOPO_STABILITY_INTERNAL,
89 	    svc_fmri_unusable },
90 	{ NULL }
91 };
92 
93 static const topo_modops_t svc_ops =
94 	{ svc_enum, svc_release };
95 static const topo_modinfo_t svc_info =
96 	{ "svc", FM_FMRI_SCHEME_SVC, SVC_VERSION, &svc_ops };
97 
98 static int
99 svc_error(topo_mod_t *mod)
100 {
101 	switch (scf_error()) {
102 	case SCF_ERROR_NO_MEMORY:
103 		return (topo_mod_seterrno(mod, EMOD_NOMEM));
104 
105 	default:
106 		return (topo_mod_seterrno(mod, EMOD_UNKNOWN));
107 	}
108 }
109 
110 int
111 svc_init(topo_mod_t *mod, topo_version_t version)
112 {
113 	scf_handle_t *hdl;
114 
115 	if (version != SVC_VERSION)
116 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
117 
118 	if ((hdl = scf_handle_create(SCF_VERSION)) == NULL)
119 		return (svc_error(mod));
120 
121 	if (scf_handle_bind(hdl) != 0) {
122 		scf_handle_destroy(hdl);
123 		return (svc_error(mod));
124 	}
125 
126 	if (topo_mod_register(mod, &svc_info, TOPO_VERSION) != 0) {
127 		topo_mod_dprintf(mod, "failed to register svc_info: "
128 		    "%s\n", topo_mod_errmsg(mod));
129 		return (-1);
130 	}
131 
132 	topo_mod_setspecific(mod, hdl);
133 
134 	return (0);
135 }
136 
137 void
138 svc_fini(topo_mod_t *mod)
139 {
140 	scf_handle_t *hdl = topo_mod_getspecific(mod);
141 
142 	scf_handle_destroy(hdl);
143 
144 	topo_mod_unregister(mod);
145 }
146 
147 /*ARGSUSED*/
148 static int
149 svc_enum(topo_mod_t *mod, tnode_t *pnode, const char *name,
150     topo_instance_t min, topo_instance_t max, void *notused1, void *notused2)
151 {
152 	(void) topo_method_register(mod, pnode, svc_methods);
153 	return (0);
154 }
155 
156 static void
157 svc_release(topo_mod_t *mod, tnode_t *node)
158 {
159 	topo_method_unregister_all(mod, node);
160 }
161 
162 static boolean_t
163 svc_component_valid(const char *str)
164 {
165 	if (str == NULL)
166 		return (B_TRUE);
167 
168 	if (*str == '\0')
169 		return (B_FALSE);
170 
171 	if (strpbrk(str, "@/:") != NULL)
172 		return (B_FALSE);
173 
174 	return (B_TRUE);
175 }
176 
177 /*ARGSUSED*/
178 static int
179 svc_fmri_nvl2str(topo_mod_t *mod, tnode_t *node, topo_version_t version,
180     nvlist_t *nvl, nvlist_t **out)
181 {
182 	uint8_t scheme_version;
183 	char *scope = NULL;
184 	char *fqn = NULL;
185 	char *contract = NULL;
186 	char *instance = NULL;
187 	char *service;
188 	int err;
189 	char *buf = NULL;
190 	size_t buflen = 0;
191 	ssize_t size = 0;
192 	nvlist_t *fmristr;
193 
194 	if (version > TOPO_METH_NVL2STR_VERSION)
195 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
196 
197 	if (nvlist_lookup_uint8(nvl, FM_VERSION, &scheme_version) != 0 ||
198 	    scheme_version > FM_SVC_SCHEME_VERSION)
199 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
200 
201 	/*
202 	 * Check for optional members.
203 	 */
204 	err = nvlist_lookup_string(nvl, FM_FMRI_SVC_INSTANCE, &instance);
205 	if ((err != 0 && err != ENOENT) || !svc_component_valid(instance))
206 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
207 	err = nvlist_lookup_string(nvl, FM_FMRI_SVC_AUTH_SCOPE, &scope);
208 	if ((err != 0 && err != ENOENT) || !svc_component_valid(scope))
209 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
210 	err = nvlist_lookup_string(nvl, FM_FMRI_SVC_AUTH_SYSTEM_FQN, &fqn);
211 	if ((err != 0 && err != ENOENT) || !svc_component_valid(scope))
212 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
213 	err = nvlist_lookup_string(nvl, FM_FMRI_SVC_CONTRACT_ID, &contract);
214 	if ((err != 0 && err != ENOENT) || !svc_component_valid(contract))
215 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
216 
217 	/*
218 	 * Get the service name.
219 	 */
220 	if (nvlist_lookup_string(nvl, FM_FMRI_SVC_NAME, &service) != 0)
221 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
222 
223 	/*
224 	 * We make two passes through this code.  The first time through we
225 	 * calculate the size of buffer that we'll need, and the second time
226 	 * through we fill it in.
227 	 */
228 again:
229 	/*
230 	 * svc://[scope@][system-fqn]
231 	 */
232 	topo_fmristr_build(&size, buf, buflen, FM_FMRI_SCHEME_SVC,
233 	    NULL, "://");
234 	topo_fmristr_build(&size, buf, buflen, scope, NULL, "@");
235 	topo_fmristr_build(&size, buf, buflen, fqn, NULL, NULL);
236 
237 	/* svc path */
238 	if (*service == '\0')
239 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
240 
241 	topo_fmristr_build(&size, buf, buflen, service, "/", NULL);
242 
243 	/* [:instance][@contract-id] */
244 	topo_fmristr_build(&size, buf, buflen, instance, ":", NULL);
245 	topo_fmristr_build(&size, buf, buflen, contract, "@", NULL);
246 
247 	if (buf == NULL) {
248 		if ((buf = topo_mod_alloc(mod, size + 1)) == NULL)
249 			return (topo_mod_seterrno(mod, EMOD_NOMEM));
250 
251 		buflen = size + 1;
252 		size = 0;
253 		goto again;
254 	}
255 
256 	/*
257 	 * Construct the nvlist to return as the result.
258 	 */
259 	if (topo_mod_nvalloc(mod, &fmristr, NV_UNIQUE_NAME) != 0) {
260 		topo_mod_strfree(mod, buf);
261 		return (topo_mod_seterrno(mod, EMOD_NOMEM));
262 	}
263 
264 	if (nvlist_add_string(fmristr, "fmri-string", buf) != 0) {
265 		topo_mod_strfree(mod, buf);
266 		nvlist_free(fmristr);
267 		return (topo_mod_seterrno(mod, EMOD_NOMEM));
268 	}
269 	topo_mod_strfree(mod, buf);
270 	*out = fmristr;
271 
272 	return (0);
273 }
274 
275 /*ARGSUSED*/
276 static int
277 svc_fmri_str2nvl(topo_mod_t *mod, tnode_t *node, topo_version_t version,
278     nvlist_t *in, nvlist_t **out)
279 {
280 	nvlist_t *fmri;
281 	char *str, *loc, val;
282 
283 	if (version > TOPO_METH_STR2NVL_VERSION)
284 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
285 
286 	if (nvlist_lookup_string(in, "fmri-string", &str) != 0)
287 		return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
288 
289 	if (strncmp(str, "svc://", 6) != 0)
290 		return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));
291 
292 	if (topo_mod_nvalloc(mod, &fmri, NV_UNIQUE_NAME) != 0)
293 		return (topo_mod_seterrno(mod, EMOD_NOMEM));
294 
295 	str += 6;
296 	if ((loc = strpbrk(str, "@/")) == NULL)
297 		goto malformed;
298 
299 	if (*loc == '@') {
300 		/* scope */
301 		*loc = '\0';
302 		if (!svc_component_valid(str)) {
303 			*loc = '@';
304 			goto malformed;
305 		}
306 
307 		if (nvlist_add_string(fmri, FM_FMRI_SVC_AUTH_SCOPE, str) != 0) {
308 			*loc = '@';
309 			goto nomem;
310 		}
311 
312 		*loc = '@';
313 		str = loc + 1;
314 		if ((loc = strchr(str, '/')) == NULL)
315 			goto malformed;
316 	}
317 
318 	if (loc != str) {
319 		/* system-fqn */
320 		*loc = '\0';
321 		if (!svc_component_valid(str)) {
322 			*loc = '/';
323 			goto malformed;
324 		}
325 
326 		if (nvlist_add_string(fmri, FM_FMRI_SVC_AUTH_SYSTEM_FQN,
327 		    str) != 0) {
328 			*loc = '/';
329 			goto nomem;
330 		}
331 
332 		*loc = '/';
333 	}
334 
335 	str = loc + 1;
336 	loc = strpbrk(str, ":@");
337 
338 	if (str[0] == '\0' || loc == str)
339 		goto malformed;
340 
341 	if (loc != NULL) {
342 		val = *loc;
343 		*loc = '\0';
344 	}
345 
346 	/* service name */
347 	if (nvlist_add_string(fmri, FM_FMRI_SVC_NAME, str) != 0) {
348 		if (loc != NULL)
349 			*loc = val;
350 		goto nomem;
351 	}
352 
353 	if (loc != NULL)
354 		*loc = val;
355 
356 	if (loc != NULL && *loc == ':') {
357 		/* instance */
358 		str = loc + 1;
359 		if (str[0] == '\0' || str[0] == '@')
360 			goto malformed;
361 
362 		loc = strchr(str, '@');
363 		if (loc != NULL)
364 			*loc = '\0';
365 
366 		if (nvlist_add_string(fmri, FM_FMRI_SVC_INSTANCE,
367 		    str) != 0) {
368 			if (loc != NULL)
369 				*loc = '@';
370 			goto nomem;
371 		}
372 
373 		if (loc != NULL)
374 			*loc = '@';
375 	}
376 
377 	if (loc != NULL) {
378 		/* contract-id */
379 		assert(*loc == '@');
380 		str = loc + 1;
381 		if (str[0] == '\0')
382 			goto malformed;
383 
384 		if (nvlist_add_string(fmri, FM_FMRI_SVC_CONTRACT_ID,
385 		    str) != 0) {
386 			goto nomem;
387 		}
388 	}
389 
390 	if (nvlist_add_uint8(fmri, FM_VERSION, FM_SVC_SCHEME_VERSION) != 0 ||
391 	    nvlist_add_string(fmri, FM_FMRI_SCHEME, FM_FMRI_SCHEME_SVC) != 0)
392 		goto nomem;
393 
394 	*out = fmri;
395 	return (0);
396 
397 malformed:
398 	nvlist_free(fmri);
399 	return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));
400 
401 nomem:
402 	nvlist_free(fmri);
403 	return (topo_mod_seterrno(mod, EMOD_NOMEM));
404 }
405 
406 /*
407  * This common function is shared by all consumers (present, unusable, and
408  * service_state).  It returns one of the FMD_SERVICE_STATE_* states, where
409  * FMD_SERVICE_STATE_UNKNOWN means that the FMRI is not present.
410  */
411 static int
412 svc_get_state(topo_mod_t *mod, nvlist_t *fmri, boolean_t presence_only,
413     int *ret)
414 {
415 	scf_handle_t *hdl = topo_mod_getspecific(mod);
416 	uint8_t fmversion;
417 	char *instance, *name;
418 	scf_service_t *svc = NULL;
419 	scf_scope_t *scope = NULL;
420 	scf_instance_t *inst = NULL;
421 	scf_property_t *prop = NULL;
422 	scf_iter_t *iter = NULL;
423 	scf_value_t *val = NULL;
424 	scf_propertygroup_t *pg = NULL;
425 	int err, retval = 0;
426 	ssize_t len;
427 	char *state;
428 
429 	if (nvlist_lookup_uint8(fmri, FM_VERSION, &fmversion) != 0 ||
430 	    fmversion > FM_SVC_SCHEME_VERSION ||
431 	    nvlist_lookup_string(fmri, FM_FMRI_SVC_NAME, &name) != 0)
432 		return (topo_mod_seterrno(mod, EMOD_FMRI_MALFORM));
433 
434 	if ((svc = scf_service_create(hdl)) == NULL ||
435 	    (inst = scf_instance_create(hdl)) == NULL ||
436 	    (scope = scf_scope_create(hdl)) == NULL ||
437 	    (prop = scf_property_create(hdl)) == NULL ||
438 	    (iter = scf_iter_create(hdl)) == NULL ||
439 	    (pg = scf_pg_create(hdl)) == NULL ||
440 	    (val = scf_value_create(hdl)) == NULL)
441 		goto error;
442 
443 	if (scf_handle_get_scope(hdl, SCF_SCOPE_LOCAL, scope) != 0)
444 		goto error;
445 
446 	/*
447 	 * If we fail to get the service due to _DELETED or _NOT_FOUND, then we
448 	 * treat this as not present.
449 	 */
450 	if (scf_scope_get_service(scope, name, svc) != 0) {
451 		err = scf_error();
452 		if (err == SCF_ERROR_NOT_FOUND || err == SCF_ERROR_DELETED) {
453 			*ret = FMD_SERVICE_STATE_UNKNOWN;
454 			goto out;
455 		} else {
456 			goto error;
457 		}
458 	}
459 
460 	/*
461 	 * If there is no instance, then it is always present, and always
462 	 * usuable.
463 	 */
464 	if (nvlist_lookup_string(fmri, FM_FMRI_SVC_INSTANCE, &instance) != 0) {
465 		*ret = FMD_SERVICE_STATE_OK;
466 		goto out;
467 	}
468 
469 	/*
470 	 * Again, check for _DELETED or _NOT_FOUND.
471 	 */
472 	if (scf_service_get_instance(svc, instance, inst) != 0) {
473 		err = scf_error();
474 		if (err == SCF_ERROR_NOT_FOUND || err == SCF_ERROR_DELETED) {
475 			*ret = FMD_SERVICE_STATE_UNKNOWN;
476 			goto out;
477 		} else {
478 			goto error;
479 		}
480 	}
481 
482 	/*
483 	 * For presence, we are done.  Otherwise, we need to get the current
484 	 * state of the instance.
485 	 */
486 	if (presence_only) {
487 		*ret = FMD_SERVICE_STATE_OK;
488 		goto out;
489 	}
490 
491 	if (scf_instance_get_pg(inst, SCF_PG_RESTARTER, pg) != 0 ||
492 	    scf_pg_get_property(pg, SCF_PROPERTY_STATE, prop) != 0 ||
493 	    scf_iter_property_values(iter, prop) != 0 ||
494 	    scf_iter_next_value(iter, val) != 1)
495 		goto error;
496 
497 	if ((len = scf_value_get_astring(val, NULL, 0)) < 0)
498 		goto error;
499 
500 	state = alloca(len + 1);
501 	if (scf_value_get_astring(val, state, len + 1) < 0)
502 		goto error;
503 
504 	if (strcmp(state, SCF_STATE_STRING_MAINT) == 0)
505 		*ret = FMD_SERVICE_STATE_UNUSABLE;
506 	else if (strcmp(state, SCF_STATE_STRING_DEGRADED) == 0)
507 		*ret = FMD_SERVICE_STATE_DEGRADED;
508 	else
509 		*ret = FMD_SERVICE_STATE_OK;
510 	goto out;
511 
512 error:
513 	retval = -1;
514 out:
515 	scf_value_destroy(val);
516 	scf_pg_destroy(pg);
517 	scf_iter_destroy(iter);
518 	scf_property_destroy(prop);
519 	scf_instance_destroy(inst);
520 	scf_scope_destroy(scope);
521 	scf_service_destroy(svc);
522 	return (retval);
523 }
524 
525 /*ARGSUSED*/
526 static int
527 svc_fmri_present(topo_mod_t *mod, tnode_t *node, topo_version_t version,
528     nvlist_t *in, nvlist_t **out)
529 {
530 	int state;
531 
532 	if (version > TOPO_METH_PRESENT_VERSION)
533 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
534 
535 	if (svc_get_state(mod, in, B_TRUE, &state) != 0)
536 		return (-1);
537 
538 	if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
539 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
540 	if (nvlist_add_uint32(*out, TOPO_METH_PRESENT_RET,
541 	    state != FMD_SERVICE_STATE_UNKNOWN) != 0) {
542 		nvlist_free(*out);
543 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
544 	}
545 
546 	return (0);
547 }
548 
549 /*ARGSUSED*/
550 static int
551 svc_fmri_replaced(topo_mod_t *mod, tnode_t *node, topo_version_t version,
552     nvlist_t *in, nvlist_t **out)
553 {
554 	int state;
555 
556 	if (version > TOPO_METH_REPLACED_VERSION)
557 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
558 
559 	if (svc_get_state(mod, in, B_TRUE, &state) != 0)
560 		return (-1);
561 
562 	if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
563 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
564 	if (nvlist_add_uint32(*out, TOPO_METH_REPLACED_RET,
565 	    state == FMD_SERVICE_STATE_UNKNOWN ?
566 	    FMD_OBJ_STATE_NOT_PRESENT : FMD_OBJ_STATE_UNKNOWN) != 0) {
567 		nvlist_free(*out);
568 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
569 	}
570 
571 	return (0);
572 }
573 
574 /*ARGSUSED*/
575 static int
576 svc_fmri_service_state(topo_mod_t *mod, tnode_t *node, topo_version_t version,
577     nvlist_t *in, nvlist_t **out)
578 {
579 	int state;
580 
581 	if (version > TOPO_METH_SERVICE_STATE_VERSION)
582 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
583 
584 	if (svc_get_state(mod, in, B_FALSE, &state) != 0)
585 		return (-1);
586 
587 	if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
588 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
589 	if (nvlist_add_uint32(*out, TOPO_METH_SERVICE_STATE_RET,
590 	    state) != 0) {
591 		nvlist_free(*out);
592 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
593 	}
594 
595 	return (0);
596 }
597 
598 /*ARGSUSED*/
599 static int
600 svc_fmri_unusable(topo_mod_t *mod, tnode_t *node, topo_version_t version,
601     nvlist_t *in, nvlist_t **out)
602 {
603 	int state;
604 
605 	if (version > TOPO_METH_UNUSABLE_VERSION)
606 		return (topo_mod_seterrno(mod, EMOD_VER_NEW));
607 
608 	if (svc_get_state(mod, in, B_FALSE, &state) != 0)
609 		return (-1);
610 
611 	if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) != 0)
612 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
613 	if (nvlist_add_uint32(*out, TOPO_METH_UNUSABLE_RET,
614 	    (state == FMD_SERVICE_STATE_UNKNOWN ||
615 	    state == FMD_SERVICE_STATE_UNUSABLE)) != 0) {
616 		nvlist_free(*out);
617 		return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
618 	}
619 
620 	return (0);
621 }
622