xref: /titanic_41/usr/src/cmd/devfsadm/disk_link.c (revision de81e71e031139a0a7f13b7bf64152c3faa76698)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <devfsadm.h>
27 #include <stdio.h>
28 #include <strings.h>
29 #include <stdlib.h>
30 #include <limits.h>
31 #include <ctype.h>
32 #include <sys/stat.h>
33 #include <bsm/devalloc.h>
34 
35 #define	DISK_SUBPATH_MAX 100
36 #define	RM_STALE 0x01
37 #define	DISK_LINK_RE	"^r?dsk/c[0-9]+(t[0-9A-F]+)?d[0-9]+(((s|p))[0-9]+)?$"
38 #define	DISK_LINK_TO_UPPER(ch)\
39 	(((ch) >= 'a' && (ch) <= 'z') ? (ch - 'a' + 'A') : ch)
40 
41 #define	SLICE_SMI	"s7"
42 #define	SLICE_EFI	""
43 
44 #define	MN_SMI		"h"
45 #define	MN_EFI		"wd"
46 #define	ASCIIWWNSIZE	255
47 
48 extern int system_labeled;
49 
50 static int disk_callback_chan(di_minor_t minor, di_node_t node);
51 static int disk_callback_nchan(di_minor_t minor, di_node_t node);
52 static int disk_callback_wwn(di_minor_t minor, di_node_t node);
53 static int disk_callback_xvmd(di_minor_t minor, di_node_t node);
54 static int disk_callback_fabric(di_minor_t minor, di_node_t node);
55 static int disk_callback_sas(di_minor_t minor, di_node_t node);
56 static void disk_common(di_minor_t minor, di_node_t node, char *disk,
57 				int flags);
58 static char *diskctrl(di_node_t node, di_minor_t minor);
59 static int reserved_links_exist(di_node_t node, di_minor_t minor, int nflags);
60 
61 
62 static devfsadm_create_t disk_cbt[] = {
63 	{ "disk", "ddi_block", NULL,
64 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
65 	},
66 	{ "disk", "ddi_block:channel", NULL,
67 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
68 	},
69 	{ "disk", "ddi_block:fabric", NULL,
70 		TYPE_EXACT, ILEVEL_0, disk_callback_fabric
71 	},
72 	{ "disk", "ddi_block:wwn", NULL,
73 	    TYPE_EXACT, ILEVEL_0, disk_callback_wwn
74 	},
75 	{ "disk", "ddi_block:sas", NULL,
76 	    TYPE_EXACT, ILEVEL_0, disk_callback_sas
77 	},
78 	{ "disk", "ddi_block:cdrom", NULL,
79 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
80 	},
81 	{ "disk", "ddi_block:cdrom:channel", NULL,
82 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
83 	},
84 	{ "disk", "ddi_block:xvmd", NULL,
85 	    TYPE_EXACT, ILEVEL_0, disk_callback_xvmd
86 	},
87 	{ "disk", "ddi_block:cdrom:xvmd", NULL,
88 	    TYPE_EXACT, ILEVEL_0, disk_callback_xvmd
89 	},
90 };
91 
92 DEVFSADM_CREATE_INIT_V0(disk_cbt);
93 
94 /*
95  * HOT auto cleanup of disks not desired.
96  */
97 static devfsadm_remove_t disk_remove_cbt[] = {
98 	{ "disk", DISK_LINK_RE, RM_POST,
99 		ILEVEL_0, devfsadm_rm_all
100 	}
101 };
102 
103 DEVFSADM_REMOVE_INIT_V0(disk_remove_cbt);
104 
105 static devlink_re_t disks_re_array[] = {
106 	{"^r?dsk/c([0-9]+)", 1},
107 	{"^cfg/c([0-9]+)$", 1},
108 	{"^scsi/.+/c([0-9]+)", 1},
109 	{NULL}
110 };
111 
112 static char *disk_mid = "disk_mid";
113 static char *modname = "disk_link";
114 
115 int
116 minor_init()
117 {
118 	devfsadm_print(disk_mid,
119 	    "%s: minor_init(): Creating disks reserved ID cache\n",
120 	    modname);
121 	return (devfsadm_reserve_id_cache(disks_re_array, NULL));
122 }
123 
124 static int
125 disk_callback_chan(di_minor_t minor, di_node_t node)
126 {
127 	char *addr;
128 	char disk[20];
129 	uint_t targ;
130 	uint_t lun;
131 
132 	addr = di_bus_addr(node);
133 	(void) sscanf(addr, "%X,%X", &targ, &lun);
134 	(void) sprintf(disk, "t%dd%d", targ, lun);
135 	disk_common(minor, node, disk, 0);
136 	return (DEVFSADM_CONTINUE);
137 
138 }
139 
140 static int
141 disk_callback_nchan(di_minor_t minor, di_node_t node)
142 {
143 	char *addr;
144 	char disk[10];
145 	uint_t lun;
146 
147 	addr = di_bus_addr(node);
148 	(void) sscanf(addr, "%X", &lun);
149 	(void) sprintf(disk, "d%d", lun);
150 	disk_common(minor, node, disk, 0);
151 	return (DEVFSADM_CONTINUE);
152 
153 }
154 
155 static int
156 disk_callback_wwn(di_minor_t minor, di_node_t node)
157 {
158 	char disk[10];
159 	int lun;
160 	int targ;
161 	int *intp;
162 
163 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "target", &intp) <= 0) {
164 		return (DEVFSADM_CONTINUE);
165 	}
166 	targ = *intp;
167 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "lun", &intp) <= 0) {
168 		lun = 0;
169 	} else {
170 		lun = *intp;
171 	}
172 	(void) sprintf(disk, "t%dd%d", targ, lun);
173 
174 	disk_common(minor, node, disk, RM_STALE);
175 
176 	return (DEVFSADM_CONTINUE);
177 }
178 
179 static int
180 disk_callback_fabric(di_minor_t minor, di_node_t node)
181 {
182 	char disk[DISK_SUBPATH_MAX];
183 	int lun;
184 	int count;
185 	int *intp;
186 	uchar_t *str;
187 	uchar_t *wwn;
188 	uchar_t ascii_wwn[ASCIIWWNSIZE];
189 
190 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
191 	    "client-guid", (char **)&wwn) > 0) {
192 		if (strlcpy((char *)ascii_wwn, (char *)wwn,
193 		    sizeof (ascii_wwn)) >= sizeof (ascii_wwn)) {
194 			devfsadm_errprint("SUNW_disk_link: GUID too long:%d",
195 			    strlen((char *)wwn));
196 			return (DEVFSADM_CONTINUE);
197 		}
198 		lun = 0;
199 	} else if (di_prop_lookup_bytes(DDI_DEV_T_ANY, node,
200 	    "port-wwn", &wwn) > 0) {
201 		if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
202 		    "lun", &intp) > 0) {
203 			lun = *intp;
204 		} else {
205 			lun = 0;
206 		}
207 
208 		for (count = 0, str = ascii_wwn; count < 8; count++, str += 2) {
209 			(void) sprintf((caddr_t)str, "%02x", wwn[count]);
210 		}
211 		*str = '\0';
212 	} else {
213 		return (DEVFSADM_CONTINUE);
214 	}
215 
216 	for (str = ascii_wwn; *str != '\0'; str++) {
217 		*str = DISK_LINK_TO_UPPER(*str);
218 	}
219 
220 	(void) snprintf(disk, DISK_SUBPATH_MAX, "t%sd%d", ascii_wwn, lun);
221 
222 	disk_common(minor, node, disk, RM_STALE);
223 
224 	return (DEVFSADM_CONTINUE);
225 }
226 
227 static int
228 disk_callback_sas(di_minor_t minor, di_node_t node)
229 {
230 	char disk[DISK_SUBPATH_MAX];
231 	int lun;
232 	int *intp;
233 	char *str;
234 	char *wwn;
235 
236 	/*
237 	 * get LUN property
238 	 */
239 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
240 	    "lun", &intp) > 0) {
241 		lun = *intp;
242 	} else {
243 		lun = 0;
244 	}
245 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
246 	    "target-port", &wwn) > 0) {
247 		/*
248 		 * If the target-port property exist
249 		 * we use wwn format naming
250 		 */
251 		for (str = wwn; *str != '\0'; str++) {
252 			*str = DISK_LINK_TO_UPPER(*str);
253 		}
254 		(void) snprintf(disk, DISK_SUBPATH_MAX, "t%sd%d", wwn, lun);
255 
256 	} else if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
257 	    "sata-phy", &intp) > 0) {
258 		/*
259 		 * For direct attached SATA device without Device Name,
260 		 * no wwn exist, we use phy format naming
261 		 */
262 		(void) snprintf(disk, DISK_SUBPATH_MAX, "t%dd%d", *intp, lun);
263 	} else {
264 		return (DEVFSADM_CONTINUE);
265 	}
266 
267 	disk_common(minor, node, disk, RM_STALE);
268 
269 	return (DEVFSADM_CONTINUE);
270 }
271 
272 /*
273  * xVM virtual block device
274  *
275  * VBDs are enumerated into xenstore by xend and named using
276  * the linux dev_t values for 'hd' and 'xvd' devices.  Linux
277  * dev_t's are 16-bit values.  The upper 8 bits identify the major #
278  * of the device (hd, xvd) and the lower 8 bits the instance and partition
279  *
280  * For PV guests, VBDs are named by the virt-tools using
281  * the form xvd[a-p][1-15].  The corresponding Solaris /dev/dsk name
282  * created by this generator will be c0t[0-15]d[0-15]sN,
283  * were the target (t) value represents [a-p] and the
284  * disk (d) value is either 0 (e.g. xvda) or contains the partition
285  * information if it has been specified [1-15] (e.g. xvda1)
286  *
287  * For PV guests using the legacy naming (0, 1, 2, ...)
288  * the Solaris disk names created will be c0d[0..767]sN
289  * The Solaris version of virt-install based on virtinst.101
290  * named PV disks as sequential integers.  With virtinst.300_1 and
291  * beyond, the virt-* tools will no longer create legacy disk
292  * names.
293  */
294 static int
295 disk_callback_xvmd(di_minor_t minor, di_node_t node)
296 {
297 #define	HD_BASE (3 << 8)
298 #define	XVBDMAJ 202
299 
300 	char *addr;
301 	char disk[16];
302 	uint_t targ;
303 	uint_t lun = 0;
304 	uint_t fmaj;
305 
306 	addr = di_bus_addr(node);
307 	targ = strtol(addr, (char **)NULL, 10);
308 	fmaj = targ >> 8;
309 
310 	/* legacy device address */
311 	if (targ < HD_BASE)
312 		(void) snprintf(disk, sizeof (disk),  "d%d", targ);
313 	/* PV VBD */
314 	else if (fmaj == XVBDMAJ) {
315 		lun = targ & 0xf;
316 		targ = (targ & 0xff) >> 4;
317 		(void) snprintf(disk, sizeof (disk), "t%dd%d", targ, lun);
318 	/* HVM device names are generated using the standard generator */
319 	} else {
320 		devfsadm_errprint("%s: invalid disk device number (%s)\n",
321 		    modname, addr);
322 		return (DEVFSADM_CONTINUE);
323 	}
324 	disk_common(minor, node, disk, 0);
325 	return (DEVFSADM_CONTINUE);
326 
327 }
328 
329 /*
330  * This function is called for every disk minor node.
331  * Calls enumerate to assign a logical controller number, and
332  * then devfsadm_mklink to make the link.
333  */
334 static void
335 disk_common(di_minor_t minor, di_node_t node, char *disk, int flags)
336 {
337 	char l_path[PATH_MAX + 1];
338 	char sec_path[PATH_MAX + 1];
339 	char stale_re[DISK_SUBPATH_MAX];
340 	char *dir;
341 	char slice[4];
342 	char *mn;
343 	char *ctrl;
344 	char *nt = NULL;
345 	int *int_prop;
346 	int  nflags = 0;
347 
348 	if (strstr(mn = di_minor_name(minor), ",raw")) {
349 		dir = "rdsk";
350 	} else {
351 		dir = "dsk";
352 	}
353 
354 	if (mn[0] < 113) {
355 		(void) sprintf(slice, "s%d", mn[0] - 'a');
356 	} else if (strncmp(mn, MN_EFI, 2) != 0) {
357 		(void) sprintf(slice, "p%d", mn[0] - 'q');
358 	} else {
359 		/* For EFI label */
360 		(void) sprintf(slice, SLICE_EFI);
361 	}
362 
363 	nflags = 0;
364 	if (system_labeled) {
365 		nt = di_minor_nodetype(minor);
366 		if ((nt != NULL) &&
367 		    ((strcmp(nt, DDI_NT_CD) == 0) ||
368 		    (strcmp(nt, DDI_NT_CD_CHAN) == 0) ||
369 		    (strcmp(nt, DDI_NT_BLOCK_CHAN) == 0))) {
370 			nflags = DA_ADD|DA_CD;
371 		}
372 	}
373 
374 	if (reserved_links_exist(node, minor, nflags) == DEVFSADM_SUCCESS) {
375 		devfsadm_print(disk_mid, "Reserved link exists. Not "
376 		    "creating links for slice %s\n", slice);
377 		return;
378 	}
379 
380 	if (NULL == (ctrl = diskctrl(node, minor)))
381 		return;
382 
383 	(void) strcpy(l_path, dir);
384 	(void) strcat(l_path, "/c");
385 	(void) strcat(l_path, ctrl);
386 	(void) strcat(l_path, disk);
387 
388 	/*
389 	 * If switching between SMI and EFI label or vice versa
390 	 * cleanup the previous label's devlinks.
391 	 */
392 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
393 		char *s, tpath[PATH_MAX + 1];
394 		struct stat sb;
395 
396 		s = l_path + strlen(l_path);
397 		(void) strcat(l_path, (*mn == *(MN_SMI))
398 		    ? SLICE_EFI : SLICE_SMI);
399 		/*
400 		 * Attempt the remove only if the stale link exists
401 		 */
402 		(void) snprintf(tpath, sizeof (tpath), "%s/dev/%s",
403 		    devfsadm_root_path(), l_path);
404 		if (lstat(tpath, &sb) != -1)
405 			devfsadm_rm_all(l_path);
406 		*s = '\0';
407 	}
408 	(void) strcat(l_path, slice);
409 
410 	(void) devfsadm_mklink(l_path, node, minor, nflags);
411 
412 	/* secondary links for removable and hotpluggable devices */
413 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "removable-media",
414 	    &int_prop) >= 0) {
415 		(void) strcpy(sec_path, "removable-media/");
416 		(void) strcat(sec_path, l_path);
417 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
418 	}
419 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "hotpluggable",
420 	    &int_prop) >= 0) {
421 		(void) strcpy(sec_path, "hotpluggable/");
422 		(void) strcat(sec_path, l_path);
423 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
424 	}
425 
426 	if ((flags & RM_STALE) == RM_STALE) {
427 		(void) strcpy(stale_re, "^");
428 		(void) strcat(stale_re, dir);
429 		(void) strcat(stale_re, "/c");
430 		(void) strcat(stale_re, ctrl);
431 		(void) strcat(stale_re, "t[0-9A-F]+d[0-9]+(s[0-9]+)?$");
432 		/*
433 		 * optimizations are made inside of devfsadm_rm_stale_links
434 		 * instead of before calling the function, as it always
435 		 * needs to add the valid link to the cache.
436 		 */
437 		devfsadm_rm_stale_links(stale_re, l_path, node, minor);
438 	}
439 
440 	free(ctrl);
441 }
442 
443 
444 /* index of enumeration rule applicable to this module */
445 #define	RULE_INDEX	0
446 
447 static char *
448 diskctrl(di_node_t node, di_minor_t minor)
449 {
450 	char path[PATH_MAX + 1];
451 	char *devfspath;
452 	char *buf, *mn;
453 
454 	devfsadm_enumerate_t rules[3] = {
455 	    {"^r?dsk$/^c([0-9]+)", 1, MATCH_PARENT},
456 	    {"^cfg$/^c([0-9]+)$", 1, MATCH_ADDR},
457 	    {"^scsi$/^.+$/^c([0-9]+)", 1, MATCH_PARENT}
458 	};
459 
460 	mn = di_minor_name(minor);
461 
462 	if ((devfspath = di_devfs_path(node)) == NULL) {
463 		return (NULL);
464 	}
465 	(void) strcpy(path, devfspath);
466 	(void) strcat(path, ":");
467 	(void) strcat(path, mn);
468 	di_devfs_path_free(devfspath);
469 
470 	/*
471 	 * Use controller component of disk path
472 	 */
473 	if (disk_enumerate_int(path, RULE_INDEX, &buf, rules, 3) ==
474 	    DEVFSADM_MULTIPLE) {
475 
476 		/*
477 		 * We failed because there are multiple logical controller
478 		 * numbers for a single physical controller.  If we use node
479 		 * name also in the match it should fix this and only find one
480 		 * logical controller. (See 4045879).
481 		 * NOTE: Rules for controllers are not changed, as there is
482 		 * no unique controller number for them in this case.
483 		 *
484 		 * MATCH_UNCACHED flag is private to the "disks" and "sgen"
485 		 * modules. NOT to be used by other modules.
486 		 */
487 
488 		rules[0].flags = MATCH_NODE | MATCH_UNCACHED; /* disks */
489 		rules[2].flags = MATCH_NODE | MATCH_UNCACHED; /* generic scsi */
490 		if (devfsadm_enumerate_int(path, RULE_INDEX, &buf, rules, 3)) {
491 			return (NULL);
492 		}
493 	}
494 
495 	return (buf);
496 }
497 
498 typedef struct dvlist {
499 	char *dv_link;
500 	struct dvlist *dv_next;
501 } dvlist_t;
502 
503 static void
504 free_dvlist(dvlist_t **pp)
505 {
506 	dvlist_t *entry;
507 
508 	while (*pp) {
509 		entry = *pp;
510 		*pp = entry->dv_next;
511 		assert(entry->dv_link);
512 		free(entry->dv_link);
513 		free(entry);
514 	}
515 }
516 static int
517 dvlink_cb(di_devlink_t devlink, void *arg)
518 {
519 	char *path;
520 	char *can_path;
521 	dvlist_t **pp = (dvlist_t **)arg;
522 	dvlist_t *entry = NULL;
523 
524 	entry = calloc(1, sizeof (dvlist_t));
525 	if (entry == NULL) {
526 		devfsadm_errprint("%s: calloc failed\n", modname);
527 		goto error;
528 	}
529 
530 	path = (char *)di_devlink_path(devlink);
531 	assert(path);
532 	if (path == NULL) {
533 		devfsadm_errprint("%s: di_devlink_path() returned NULL\n",
534 		    modname);
535 		goto error;
536 	}
537 
538 	devfsadm_print(disk_mid, "%s: found link %s in reverse link cache\n",
539 	    modname, path);
540 
541 	/*
542 	 * Return linkname in canonical form i.e. without the
543 	 * "/dev/" prefix
544 	 */
545 	can_path = strstr(path, "/dev/");
546 	if (can_path == NULL) {
547 		devfsadm_errprint("%s: devlink path %s has no /dev/\n",
548 		    modname, path);
549 		goto error;
550 	}
551 
552 	entry->dv_link = s_strdup(can_path + strlen("/dev/"));
553 	entry->dv_next = *pp;
554 	*pp = entry;
555 
556 	return (DI_WALK_CONTINUE);
557 
558 error:
559 	free(entry);
560 	free_dvlist(pp);
561 	*pp = NULL;
562 	return (DI_WALK_TERMINATE);
563 }
564 
565 /*
566  * Returns success only if all goes well. If there is no matching reserved link
567  * or if there is an error, we assume no match. It is better to err on the side
568  * of caution by creating extra links than to miss out creating a required link.
569  */
570 static int
571 reserved_links_exist(di_node_t node, di_minor_t minor, int nflags)
572 {
573 	di_devlink_handle_t dvlink_cache = devfsadm_devlink_cache();
574 	char phys_path[PATH_MAX];
575 	char *minor_path;
576 	dvlist_t *head;
577 	dvlist_t *entry;
578 	char *s;
579 	char l[PATH_MAX];
580 	int switch_link = 0;
581 	char *mn = di_minor_name(minor);
582 
583 	if (dvlink_cache == NULL || mn == NULL) {
584 		devfsadm_errprint("%s: No minor or devlink cache\n", modname);
585 		return (DEVFSADM_FAILURE);
586 	}
587 
588 	if (!devfsadm_have_reserved()) {
589 		devfsadm_print(disk_mid, "%s: No reserved links\n", modname);
590 		return (DEVFSADM_FAILURE);
591 	}
592 
593 	minor_path = di_devfs_minor_path(minor);
594 	if (minor_path == NULL) {
595 		devfsadm_errprint("%s: di_devfs_minor_path failed\n", modname);
596 		return (DEVFSADM_FAILURE);
597 	}
598 
599 	(void) strlcpy(phys_path, minor_path, sizeof (phys_path));
600 
601 	di_devfs_path_free(minor_path);
602 
603 	head = NULL;
604 	(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE, phys_path,
605 	    DI_PRIMARY_LINK, &head, dvlink_cb);
606 
607 	/*
608 	 * We may be switching between EFI label and SMI label in which case
609 	 * we only have minors of the other type.
610 	 */
611 	if (head == NULL && (*mn == *(MN_SMI) ||
612 	    (strncmp(mn, MN_EFI, 2) == 0))) {
613 		devfsadm_print(disk_mid, "%s: No links for minor %s in /dev. "
614 		    "Trying another label\n", modname, mn);
615 		s = strrchr(phys_path, ':');
616 		if (s == NULL) {
617 			devfsadm_errprint("%s: invalid minor path: %s\n",
618 			    modname, phys_path);
619 			return (DEVFSADM_FAILURE);
620 		}
621 		(void) snprintf(s+1, sizeof (phys_path) - (s + 1 - phys_path),
622 		    "%s%s", *mn == *(MN_SMI) ? MN_EFI : MN_SMI,
623 		    strstr(s, ",raw") ? ",raw" : "");
624 		(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE,
625 		    phys_path, DI_PRIMARY_LINK, &head, dvlink_cb);
626 	}
627 
628 	if (head == NULL) {
629 		devfsadm_print(disk_mid, "%s: minor %s has no links in /dev\n",
630 		    modname, phys_path);
631 		/* no links on disk */
632 		return (DEVFSADM_FAILURE);
633 	}
634 
635 	/*
636 	 * It suffices to use 1 link to this minor, since
637 	 * we are matching with reserved IDs on the basis of
638 	 * the controller number which will be the same for
639 	 * all links to this minor.
640 	 */
641 	if (!devfsadm_is_reserved(disks_re_array, head->dv_link)) {
642 		/* not reserved links */
643 		devfsadm_print(disk_mid, "%s: devlink %s and its minor "
644 		    "are NOT reserved\n", modname, head->dv_link);
645 		free_dvlist(&head);
646 		return (DEVFSADM_FAILURE);
647 	}
648 
649 	devfsadm_print(disk_mid, "%s: devlink %s and its minor are on "
650 	    "reserved list\n", modname, head->dv_link);
651 
652 	/*
653 	 * Switch between SMI and EFI labels if required
654 	 */
655 	switch_link = 0;
656 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
657 		for (entry = head; entry; entry = entry->dv_next) {
658 			s = strrchr(entry->dv_link, '/');
659 			assert(s);
660 			if (s == NULL) {
661 				devfsadm_errprint("%s: disk link %s has no "
662 				    "directory\n", modname, entry->dv_link);
663 				continue;
664 			}
665 			if (*mn == *(MN_SMI) && strchr(s, 's') == NULL) {
666 				(void) snprintf(l, sizeof (l), "%s%s",
667 				    entry->dv_link, SLICE_SMI);
668 				switch_link = 1;
669 				devfsadm_print(disk_mid, "%s: switching "
670 				    "reserved link from EFI to SMI label. "
671 				    "New link is %s\n", modname, l);
672 			} else if (strncmp(mn, MN_EFI, 2) == 0 &&
673 			    (s = strchr(s, 's'))) {
674 				*s = '\0';
675 				(void) snprintf(l, sizeof (l), "%s",
676 				    entry->dv_link);
677 				*s = 's';
678 				switch_link = 1;
679 				devfsadm_print(disk_mid, "%s: switching "
680 				    "reserved link from SMI to EFI label. "
681 				    "New link is %s\n", modname, l);
682 			}
683 			if (switch_link) {
684 				devfsadm_print(disk_mid, "%s: switching "
685 				    "link: deleting %s and creating %s\n",
686 				    modname, entry->dv_link, l);
687 				devfsadm_rm_link(entry->dv_link);
688 				(void) devfsadm_mklink(l, node, minor, nflags);
689 			}
690 		}
691 	}
692 	free_dvlist(&head);
693 
694 	/*
695 	 * return SUCCESS to indicate that new links to this minor should not
696 	 * be created so that only compatibility links to this minor remain.
697 	 */
698 	return (DEVFSADM_SUCCESS);
699 }
700