xref: /titanic_41/usr/src/cmd/devfsadm/disk_link.c (revision 5fbb41393be5d63f75952b1d72d4df2642d22557)
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 #if defined(__i386) || defined(__amd64)
48 /*
49  * The number of minor nodes per LUN is defined by the disk drivers.
50  * Currently it is set to 64. Refer CMLBUNIT_SHIFT (cmlb_impl.h)
51  */
52 #define	NUM_MINORS_PER_INSTANCE	64
53 #endif
54 
55 
56 extern int system_labeled;
57 
58 static int disk_callback_chan(di_minor_t minor, di_node_t node);
59 static int disk_callback_nchan(di_minor_t minor, di_node_t node);
60 static int disk_callback_wwn(di_minor_t minor, di_node_t node);
61 static int disk_callback_xvmd(di_minor_t minor, di_node_t node);
62 static int disk_callback_fabric(di_minor_t minor, di_node_t node);
63 static int disk_callback_sas(di_minor_t minor, di_node_t node);
64 static void disk_common(di_minor_t minor, di_node_t node, char *disk,
65 				int flags);
66 static char *diskctrl(di_node_t node, di_minor_t minor);
67 static int reserved_links_exist(di_node_t node, di_minor_t minor, int nflags);
68 
69 
70 static devfsadm_create_t disk_cbt[] = {
71 	{ "disk", "ddi_block", NULL,
72 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
73 	},
74 	{ "disk", "ddi_block:channel", NULL,
75 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
76 	},
77 	{ "disk", "ddi_block:fabric", NULL,
78 		TYPE_EXACT, ILEVEL_0, disk_callback_fabric
79 	},
80 	{ "disk", "ddi_block:wwn", NULL,
81 	    TYPE_EXACT, ILEVEL_0, disk_callback_wwn
82 	},
83 	{ "disk", "ddi_block:sas", NULL,
84 	    TYPE_EXACT, ILEVEL_0, disk_callback_sas
85 	},
86 	{ "disk", "ddi_block:cdrom", NULL,
87 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
88 	},
89 	{ "disk", "ddi_block:cdrom:channel", NULL,
90 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
91 	},
92 	{ "disk", "ddi_block:xvmd", NULL,
93 	    TYPE_EXACT, ILEVEL_0, disk_callback_xvmd
94 	},
95 	{ "disk", "ddi_block:cdrom:xvmd", NULL,
96 	    TYPE_EXACT, ILEVEL_0, disk_callback_xvmd
97 	},
98 };
99 
100 DEVFSADM_CREATE_INIT_V0(disk_cbt);
101 
102 /*
103  * HOT auto cleanup of disks not desired.
104  */
105 static devfsadm_remove_t disk_remove_cbt[] = {
106 	{ "disk", DISK_LINK_RE, RM_POST,
107 		ILEVEL_0, devfsadm_rm_all
108 	}
109 };
110 
111 DEVFSADM_REMOVE_INIT_V0(disk_remove_cbt);
112 
113 static devlink_re_t disks_re_array[] = {
114 	{"^r?dsk/c([0-9]+)", 1},
115 	{"^cfg/c([0-9]+)$", 1},
116 	{"^scsi/.+/c([0-9]+)", 1},
117 	{NULL}
118 };
119 
120 static char *disk_mid = "disk_mid";
121 static char *modname = "disk_link";
122 
123 int
124 minor_init()
125 {
126 	devfsadm_print(disk_mid,
127 	    "%s: minor_init(): Creating disks reserved ID cache\n",
128 	    modname);
129 	return (devfsadm_reserve_id_cache(disks_re_array, NULL));
130 }
131 
132 static int
133 disk_callback_chan(di_minor_t minor, di_node_t node)
134 {
135 	char *addr;
136 	char disk[20];
137 	uint_t targ;
138 	uint_t lun;
139 
140 	addr = di_bus_addr(node);
141 	(void) sscanf(addr, "%X,%X", &targ, &lun);
142 	(void) sprintf(disk, "t%dd%d", targ, lun);
143 	disk_common(minor, node, disk, 0);
144 	return (DEVFSADM_CONTINUE);
145 
146 }
147 
148 static int
149 disk_callback_nchan(di_minor_t minor, di_node_t node)
150 {
151 	char *addr;
152 	char disk[10];
153 	uint_t lun;
154 
155 	addr = di_bus_addr(node);
156 	(void) sscanf(addr, "%X", &lun);
157 	(void) sprintf(disk, "d%d", lun);
158 	disk_common(minor, node, disk, 0);
159 	return (DEVFSADM_CONTINUE);
160 
161 }
162 
163 static int
164 disk_callback_wwn(di_minor_t minor, di_node_t node)
165 {
166 	char disk[10];
167 	int lun;
168 	int targ;
169 	int *intp;
170 
171 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "target", &intp) <= 0) {
172 		return (DEVFSADM_CONTINUE);
173 	}
174 	targ = *intp;
175 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "lun", &intp) <= 0) {
176 		lun = 0;
177 	} else {
178 		lun = *intp;
179 	}
180 	(void) sprintf(disk, "t%dd%d", targ, lun);
181 
182 	disk_common(minor, node, disk, RM_STALE);
183 
184 	return (DEVFSADM_CONTINUE);
185 }
186 
187 static int
188 disk_callback_fabric(di_minor_t minor, di_node_t node)
189 {
190 	char disk[DISK_SUBPATH_MAX];
191 	int lun;
192 	int count;
193 	int *intp;
194 	uchar_t *str;
195 	uchar_t *wwn;
196 	uchar_t ascii_wwn[ASCIIWWNSIZE];
197 
198 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
199 	    "client-guid", (char **)&wwn) > 0) {
200 		if (strlcpy((char *)ascii_wwn, (char *)wwn,
201 		    sizeof (ascii_wwn)) >= sizeof (ascii_wwn)) {
202 			devfsadm_errprint("SUNW_disk_link: GUID too long:%d",
203 			    strlen((char *)wwn));
204 			return (DEVFSADM_CONTINUE);
205 		}
206 		lun = 0;
207 	} else if (di_prop_lookup_bytes(DDI_DEV_T_ANY, node,
208 	    "port-wwn", &wwn) > 0) {
209 		if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
210 		    "lun", &intp) > 0) {
211 			lun = *intp;
212 		} else {
213 			lun = 0;
214 		}
215 
216 		for (count = 0, str = ascii_wwn; count < 8; count++, str += 2) {
217 			(void) sprintf((caddr_t)str, "%02x", wwn[count]);
218 		}
219 		*str = '\0';
220 	} else {
221 		return (DEVFSADM_CONTINUE);
222 	}
223 
224 	for (str = ascii_wwn; *str != '\0'; str++) {
225 		*str = DISK_LINK_TO_UPPER(*str);
226 	}
227 
228 	(void) snprintf(disk, DISK_SUBPATH_MAX, "t%sd%d", ascii_wwn, lun);
229 
230 	disk_common(minor, node, disk, RM_STALE);
231 
232 	return (DEVFSADM_CONTINUE);
233 }
234 
235 static int
236 disk_callback_sas(di_minor_t minor, di_node_t node)
237 {
238 	char disk[DISK_SUBPATH_MAX];
239 	int lun;
240 	int *intp;
241 	char *str;
242 	char *wwn;
243 
244 	/*
245 	 * get LUN property
246 	 */
247 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
248 	    "lun", &intp) > 0) {
249 		lun = *intp;
250 	} else {
251 		lun = 0;
252 	}
253 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
254 	    "target-port", &wwn) > 0) {
255 		/*
256 		 * If the target-port property exist
257 		 * we use wwn format naming
258 		 */
259 		for (str = wwn; *str != '\0'; str++) {
260 			*str = DISK_LINK_TO_UPPER(*str);
261 		}
262 		(void) snprintf(disk, DISK_SUBPATH_MAX, "t%sd%d", wwn, lun);
263 
264 	} else if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
265 	    "sata-phy", &intp) > 0) {
266 		/*
267 		 * For direct attached SATA device without Device Name,
268 		 * no wwn exist, we use phy format naming
269 		 */
270 		(void) snprintf(disk, DISK_SUBPATH_MAX, "t%dd%d", *intp, lun);
271 	} else {
272 		return (DEVFSADM_CONTINUE);
273 	}
274 
275 	disk_common(minor, node, disk, RM_STALE);
276 
277 	return (DEVFSADM_CONTINUE);
278 }
279 
280 /*
281  * xVM virtual block device
282  *
283  * VBDs are enumerated into xenstore by xend and named using
284  * the linux dev_t values for 'hd' and 'xvd' devices.  Linux
285  * dev_t's are 16-bit values.  The upper 8 bits identify the major #
286  * of the device (hd, xvd) and the lower 8 bits the instance and partition
287  *
288  * For PV guests, VBDs are named by the virt-tools using
289  * the form xvd[a-p][1-15].  The corresponding Solaris /dev/dsk name
290  * created by this generator will be c0t[0-15]d[0-15]sN,
291  * were the target (t) value represents [a-p] and the
292  * disk (d) value is either 0 (e.g. xvda) or contains the partition
293  * information if it has been specified [1-15] (e.g. xvda1)
294  *
295  * For PV guests using the legacy naming (0, 1, 2, ...)
296  * the Solaris disk names created will be c0d[0..767]sN
297  * The Solaris version of virt-install based on virtinst.101
298  * named PV disks as sequential integers.  With virtinst.300_1 and
299  * beyond, the virt-* tools will no longer create legacy disk
300  * names.
301  */
302 static int
303 disk_callback_xvmd(di_minor_t minor, di_node_t node)
304 {
305 #define	HD_BASE (3 << 8)
306 #define	XVBDMAJ 202
307 
308 	char *addr;
309 	char disk[16];
310 	uint_t targ;
311 	uint_t lun = 0;
312 	uint_t fmaj;
313 
314 	addr = di_bus_addr(node);
315 	targ = strtol(addr, (char **)NULL, 10);
316 	fmaj = targ >> 8;
317 
318 	/* legacy device address */
319 	if (targ < HD_BASE)
320 		(void) snprintf(disk, sizeof (disk),  "d%d", targ);
321 	/* PV VBD */
322 	else if (fmaj == XVBDMAJ) {
323 		lun = targ & 0xf;
324 		targ = (targ & 0xff) >> 4;
325 		(void) snprintf(disk, sizeof (disk), "t%dd%d", targ, lun);
326 	/* HVM device names are generated using the standard generator */
327 	} else {
328 		devfsadm_errprint("%s: invalid disk device number (%s)\n",
329 		    modname, addr);
330 		return (DEVFSADM_CONTINUE);
331 	}
332 	disk_common(minor, node, disk, 0);
333 	return (DEVFSADM_CONTINUE);
334 
335 }
336 
337 /*
338  * This function is called for every disk minor node.
339  * Calls enumerate to assign a logical controller number, and
340  * then devfsadm_mklink to make the link.
341  */
342 static void
343 disk_common(di_minor_t minor, di_node_t node, char *disk, int flags)
344 {
345 	char l_path[PATH_MAX + 1];
346 	char sec_path[PATH_MAX + 1];
347 	char stale_re[DISK_SUBPATH_MAX];
348 	char *dir;
349 	char slice[4];
350 	char *mn;
351 	char *ctrl;
352 	char *nt = NULL;
353 	int *int_prop;
354 	int  nflags = 0;
355 #if defined(__i386) || defined(__amd64)
356 	char mn_copy[4];
357 	char *part;
358 	int part_num;
359 #endif
360 
361 	mn = di_minor_name(minor);
362 	if (strstr(mn, ",raw")) {
363 		dir = "rdsk";
364 #if defined(__i386) || defined(__amd64)
365 		(void) strncpy(mn_copy, mn, 4);
366 		part = strtok(mn_copy, ",");
367 #endif
368 	} else {
369 		dir = "dsk";
370 #if defined(__i386) || defined(__amd64)
371 		part = mn;
372 #endif
373 	}
374 
375 #if defined(__i386) || defined(__amd64)
376 	/*
377 	 * The following is a table describing the allocation of
378 	 * minor numbers, minor names and /dev/dsk names for partitions
379 	 * and slices on x86 systems.
380 	 *
381 	 *	Minor Number	Minor Name	/dev/dsk name
382 	 *	---------------------------------------------
383 	 *	0 to 15		"a" to "p"	s0 to s15
384 	 *	16		"q"		p0
385 	 *	17 to 20	"r" to "u"	p1 to p4
386 	 *	21 to 52	"p5" to "p36"	p5 to p36
387 	 *
388 	 */
389 	part_num = atoi(part + 1);
390 
391 	if ((mn[0] == 'p') && (part_num >= 5)) {
392 		/* logical drive */
393 		(void) snprintf(slice, 4, "%s", part);
394 	} else {
395 #endif
396 	if (mn[0] < 'q') {
397 		(void) sprintf(slice, "s%d", mn[0] - 'a');
398 	} else if (strncmp(mn, MN_EFI, 2) != 0) {
399 		(void) sprintf(slice, "p%d", mn[0] - 'q');
400 	} else {
401 		/* For EFI label */
402 		(void) sprintf(slice, SLICE_EFI);
403 	}
404 #if defined(__i386) || defined(__amd64)
405 	}
406 #endif
407 
408 	nflags = 0;
409 	if (system_labeled) {
410 		nt = di_minor_nodetype(minor);
411 		if ((nt != NULL) &&
412 		    ((strcmp(nt, DDI_NT_CD) == 0) ||
413 		    (strcmp(nt, DDI_NT_CD_CHAN) == 0) ||
414 		    (strcmp(nt, DDI_NT_BLOCK_CHAN) == 0))) {
415 			nflags = DA_ADD|DA_CD;
416 		}
417 	}
418 
419 	if (reserved_links_exist(node, minor, nflags) == DEVFSADM_SUCCESS) {
420 		devfsadm_print(disk_mid, "Reserved link exists. Not "
421 		    "creating links for slice %s\n", slice);
422 		return;
423 	}
424 
425 	if (NULL == (ctrl = diskctrl(node, minor)))
426 		return;
427 
428 	(void) strcpy(l_path, dir);
429 	(void) strcat(l_path, "/c");
430 	(void) strcat(l_path, ctrl);
431 	(void) strcat(l_path, disk);
432 
433 	/*
434 	 * If switching between SMI and EFI label or vice versa
435 	 * cleanup the previous label's devlinks.
436 	 */
437 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
438 		char *s, tpath[PATH_MAX + 1];
439 		struct stat sb;
440 
441 		s = l_path + strlen(l_path);
442 		(void) strcat(l_path, (*mn == *(MN_SMI))
443 		    ? SLICE_EFI : SLICE_SMI);
444 		/*
445 		 * Attempt the remove only if the stale link exists
446 		 */
447 		(void) snprintf(tpath, sizeof (tpath), "%s/dev/%s",
448 		    devfsadm_root_path(), l_path);
449 		if (lstat(tpath, &sb) != -1)
450 			devfsadm_rm_all(l_path);
451 		*s = '\0';
452 	}
453 	(void) strcat(l_path, slice);
454 
455 	(void) devfsadm_mklink(l_path, node, minor, nflags);
456 
457 	/* secondary links for removable and hotpluggable devices */
458 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "removable-media",
459 	    &int_prop) >= 0) {
460 		(void) strcpy(sec_path, "removable-media/");
461 		(void) strcat(sec_path, l_path);
462 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
463 	}
464 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "hotpluggable",
465 	    &int_prop) >= 0) {
466 		(void) strcpy(sec_path, "hotpluggable/");
467 		(void) strcat(sec_path, l_path);
468 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
469 	}
470 
471 	if ((flags & RM_STALE) == RM_STALE) {
472 		(void) strcpy(stale_re, "^");
473 		(void) strcat(stale_re, dir);
474 		(void) strcat(stale_re, "/c");
475 		(void) strcat(stale_re, ctrl);
476 		(void) strcat(stale_re, "t[0-9A-F]+d[0-9]+(s[0-9]+)?$");
477 		/*
478 		 * optimizations are made inside of devfsadm_rm_stale_links
479 		 * instead of before calling the function, as it always
480 		 * needs to add the valid link to the cache.
481 		 */
482 		devfsadm_rm_stale_links(stale_re, l_path, node, minor);
483 	}
484 
485 	free(ctrl);
486 }
487 
488 
489 /* index of enumeration rule applicable to this module */
490 #define	RULE_INDEX	0
491 
492 static char *
493 diskctrl(di_node_t node, di_minor_t minor)
494 {
495 	char path[PATH_MAX + 1];
496 	char *devfspath;
497 	char *buf, *mn;
498 
499 	devfsadm_enumerate_t rules[3] = {
500 	    {"^r?dsk$/^c([0-9]+)", 1, MATCH_PARENT},
501 	    {"^cfg$/^c([0-9]+)$", 1, MATCH_ADDR},
502 	    {"^scsi$/^.+$/^c([0-9]+)", 1, MATCH_PARENT}
503 	};
504 
505 	mn = di_minor_name(minor);
506 
507 	if ((devfspath = di_devfs_path(node)) == NULL) {
508 		return (NULL);
509 	}
510 	(void) strcpy(path, devfspath);
511 	(void) strcat(path, ":");
512 	(void) strcat(path, mn);
513 	di_devfs_path_free(devfspath);
514 
515 	/*
516 	 * Use controller component of disk path
517 	 */
518 	if (disk_enumerate_int(path, RULE_INDEX, &buf, rules, 3) ==
519 	    DEVFSADM_MULTIPLE) {
520 
521 		/*
522 		 * We failed because there are multiple logical controller
523 		 * numbers for a single physical controller.  If we use node
524 		 * name also in the match it should fix this and only find one
525 		 * logical controller. (See 4045879).
526 		 * NOTE: Rules for controllers are not changed, as there is
527 		 * no unique controller number for them in this case.
528 		 *
529 		 * MATCH_UNCACHED flag is private to the "disks" and "sgen"
530 		 * modules. NOT to be used by other modules.
531 		 */
532 
533 		rules[0].flags = MATCH_NODE | MATCH_UNCACHED; /* disks */
534 		rules[2].flags = MATCH_NODE | MATCH_UNCACHED; /* generic scsi */
535 		if (devfsadm_enumerate_int(path, RULE_INDEX, &buf, rules, 3)) {
536 			return (NULL);
537 		}
538 	}
539 
540 	return (buf);
541 }
542 
543 typedef struct dvlist {
544 	char *dv_link;
545 	struct dvlist *dv_next;
546 } dvlist_t;
547 
548 static void
549 free_dvlist(dvlist_t **pp)
550 {
551 	dvlist_t *entry;
552 
553 	while (*pp) {
554 		entry = *pp;
555 		*pp = entry->dv_next;
556 		assert(entry->dv_link);
557 		free(entry->dv_link);
558 		free(entry);
559 	}
560 }
561 static int
562 dvlink_cb(di_devlink_t devlink, void *arg)
563 {
564 	char *path;
565 	char *can_path;
566 	dvlist_t **pp = (dvlist_t **)arg;
567 	dvlist_t *entry = NULL;
568 
569 	entry = calloc(1, sizeof (dvlist_t));
570 	if (entry == NULL) {
571 		devfsadm_errprint("%s: calloc failed\n", modname);
572 		goto error;
573 	}
574 
575 	path = (char *)di_devlink_path(devlink);
576 	assert(path);
577 	if (path == NULL) {
578 		devfsadm_errprint("%s: di_devlink_path() returned NULL\n",
579 		    modname);
580 		goto error;
581 	}
582 
583 	devfsadm_print(disk_mid, "%s: found link %s in reverse link cache\n",
584 	    modname, path);
585 
586 	/*
587 	 * Return linkname in canonical form i.e. without the
588 	 * "/dev/" prefix
589 	 */
590 	can_path = strstr(path, "/dev/");
591 	if (can_path == NULL) {
592 		devfsadm_errprint("%s: devlink path %s has no /dev/\n",
593 		    modname, path);
594 		goto error;
595 	}
596 
597 	entry->dv_link = s_strdup(can_path + strlen("/dev/"));
598 	entry->dv_next = *pp;
599 	*pp = entry;
600 
601 	return (DI_WALK_CONTINUE);
602 
603 error:
604 	free(entry);
605 	free_dvlist(pp);
606 	*pp = NULL;
607 	return (DI_WALK_TERMINATE);
608 }
609 
610 /*
611  * Returns success only if all goes well. If there is no matching reserved link
612  * or if there is an error, we assume no match. It is better to err on the side
613  * of caution by creating extra links than to miss out creating a required link.
614  */
615 static int
616 reserved_links_exist(di_node_t node, di_minor_t minor, int nflags)
617 {
618 	di_devlink_handle_t dvlink_cache = devfsadm_devlink_cache();
619 	char phys_path[PATH_MAX];
620 	char *minor_path;
621 	dvlist_t *head;
622 	dvlist_t *entry;
623 	char *s;
624 	char l[PATH_MAX];
625 	int switch_link = 0;
626 	char *mn = di_minor_name(minor);
627 
628 	if (dvlink_cache == NULL || mn == NULL) {
629 		devfsadm_errprint("%s: No minor or devlink cache\n", modname);
630 		return (DEVFSADM_FAILURE);
631 	}
632 
633 	if (!devfsadm_have_reserved()) {
634 		devfsadm_print(disk_mid, "%s: No reserved links\n", modname);
635 		return (DEVFSADM_FAILURE);
636 	}
637 
638 	minor_path = di_devfs_minor_path(minor);
639 	if (minor_path == NULL) {
640 		devfsadm_errprint("%s: di_devfs_minor_path failed\n", modname);
641 		return (DEVFSADM_FAILURE);
642 	}
643 
644 	(void) strlcpy(phys_path, minor_path, sizeof (phys_path));
645 
646 	di_devfs_path_free(minor_path);
647 
648 	head = NULL;
649 	(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE, phys_path,
650 	    DI_PRIMARY_LINK, &head, dvlink_cb);
651 
652 	/*
653 	 * We may be switching between EFI label and SMI label in which case
654 	 * we only have minors of the other type.
655 	 */
656 	if (head == NULL && (*mn == *(MN_SMI) ||
657 	    (strncmp(mn, MN_EFI, 2) == 0))) {
658 		devfsadm_print(disk_mid, "%s: No links for minor %s in /dev. "
659 		    "Trying another label\n", modname, mn);
660 		s = strrchr(phys_path, ':');
661 		if (s == NULL) {
662 			devfsadm_errprint("%s: invalid minor path: %s\n",
663 			    modname, phys_path);
664 			return (DEVFSADM_FAILURE);
665 		}
666 		(void) snprintf(s+1, sizeof (phys_path) - (s + 1 - phys_path),
667 		    "%s%s", *mn == *(MN_SMI) ? MN_EFI : MN_SMI,
668 		    strstr(s, ",raw") ? ",raw" : "");
669 		(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE,
670 		    phys_path, DI_PRIMARY_LINK, &head, dvlink_cb);
671 	}
672 
673 	if (head == NULL) {
674 		devfsadm_print(disk_mid, "%s: minor %s has no links in /dev\n",
675 		    modname, phys_path);
676 		/* no links on disk */
677 		return (DEVFSADM_FAILURE);
678 	}
679 
680 	/*
681 	 * It suffices to use 1 link to this minor, since
682 	 * we are matching with reserved IDs on the basis of
683 	 * the controller number which will be the same for
684 	 * all links to this minor.
685 	 */
686 	if (!devfsadm_is_reserved(disks_re_array, head->dv_link)) {
687 		/* not reserved links */
688 		devfsadm_print(disk_mid, "%s: devlink %s and its minor "
689 		    "are NOT reserved\n", modname, head->dv_link);
690 		free_dvlist(&head);
691 		return (DEVFSADM_FAILURE);
692 	}
693 
694 	devfsadm_print(disk_mid, "%s: devlink %s and its minor are on "
695 	    "reserved list\n", modname, head->dv_link);
696 
697 	/*
698 	 * Switch between SMI and EFI labels if required
699 	 */
700 	switch_link = 0;
701 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
702 		for (entry = head; entry; entry = entry->dv_next) {
703 			s = strrchr(entry->dv_link, '/');
704 			assert(s);
705 			if (s == NULL) {
706 				devfsadm_errprint("%s: disk link %s has no "
707 				    "directory\n", modname, entry->dv_link);
708 				continue;
709 			}
710 			if (*mn == *(MN_SMI) && strchr(s, 's') == NULL) {
711 				(void) snprintf(l, sizeof (l), "%s%s",
712 				    entry->dv_link, SLICE_SMI);
713 				switch_link = 1;
714 				devfsadm_print(disk_mid, "%s: switching "
715 				    "reserved link from EFI to SMI label. "
716 				    "New link is %s\n", modname, l);
717 			} else if (strncmp(mn, MN_EFI, 2) == 0 &&
718 			    (s = strchr(s, 's'))) {
719 				*s = '\0';
720 				(void) snprintf(l, sizeof (l), "%s",
721 				    entry->dv_link);
722 				*s = 's';
723 				switch_link = 1;
724 				devfsadm_print(disk_mid, "%s: switching "
725 				    "reserved link from SMI to EFI label. "
726 				    "New link is %s\n", modname, l);
727 			}
728 			if (switch_link) {
729 				devfsadm_print(disk_mid, "%s: switching "
730 				    "link: deleting %s and creating %s\n",
731 				    modname, entry->dv_link, l);
732 				devfsadm_rm_link(entry->dv_link);
733 				(void) devfsadm_mklink(l, node, minor, nflags);
734 			}
735 		}
736 	}
737 	free_dvlist(&head);
738 
739 	/*
740 	 * return SUCCESS to indicate that new links to this minor should not
741 	 * be created so that only compatibility links to this minor remain.
742 	 */
743 	return (DEVFSADM_SUCCESS);
744 }
745